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SUBTITLE D
TECHNICAL
TRAINING MANUAL
U.S. Environmental Protection Agency
Region IV
Atlanta, Georgia
1994
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SUBTITLE D
TECHNICAL
TRAINING MANUAL
U.S. Environmental Protection Agency
Region IV
Atlanta, Georgia
1994
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This Manual Was Developed For EPA Region IV
Office Of Solid Waste By Dynamac Corporation
Under EPA Contract 68-W9-0005 (TES VIII), Work
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RCRA SUBTITLE D TECHNICAL TRAINING COURSE
FOR STATES IN REGION IV
AGENDA
TIME:
8:00 a.m. - 4:30 p.m.
DAY 1
Manual
Section
Reference
REGISTRATION
8:00 a.m. - 9:00 a.m.
Session 1
9:00 a.m. - 11:45 a.m.
1.
General Overview - Robert Krasko, P.G.
2.
Design Criteria - J.P. Giroud, PhD.
Soil Liners
LUNCH
11:45 a.m. - 12:45 p.m.
Session 2
12:45 p.m - 4:30 p.m.
Design Criteria (Continued) - Dr. Giroud
Soil Liners
Flexible Membrane Liners
DAY 2
Session 1
8:30 a.m. -12:15 p.m.
2.
Design Criteria (Continued) - Mr. Krasko
Leachate Collection Systems
3.
Construction Quality Assurance - Robert R. Turton, P.E.
LUNCH
12:15 p.m. -1:15 p.m.
Session 2
1:15 p.m. - 4:30 p.m.
4.
Gas Management Systems - Mr. Krasko
5.
Final Cover Systems - Mr. Krasko
DAY 3
Session 1
8:30 a.m. - 12:15 p.m.
6.
Groundwater Monitoring - Mr. Krasko
LUNCH
1 2:1 5 p.m. -1:15 p.m.
Session 2
1:15 p.m. - 4:30 p.m.
Groundwater Monitoring (Continued) - Mr.
Krasko
Conclusion
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SCHEDULE OF RCRA SUBTITLE D TRAINING COURSES
May 24-26, 1994 - Raleigh, North Carolina
May 31-June 2, 1994 - Jackson, Mississippi
June 7-9, 1994 - Frankfort, Kentucky
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SPEAKERS FOR THE EPA REGION IV
RCRA SUBTITLE D TECHNICAL TRAINING COURSE
Jean-Pierre Giroud, Ph.D
Dr. Giroud is Senior Principal, Technical Director and Chairman of the Board of
Geosyntec Consultants in Boca Raton, Florida. He holds an undergraduate engineering
degree from the Ecole Centrale Des Arts et Manufactures de Paris in Paris, France and
advanced degrees from the University of Grenoble in France. He has been engage in
the practice of geotechnical engineering since 1963, and has done concentrated
research on geotextiles, geomembrances and other geosynthetics since 1969. He has
been involved in installing and researching liner systems for numerous dams and waste
landfills and field testing of geosynthetic landfill caps. He is the author of five books
and 200 technical papers.
Robert Krasko, P.G.
Mr. Krasko is President of Groundwater and Environmental Management Services,
Inc., in Lawrenceville, Georgia. He holds undergraduate degrees in biology and
geology from Florida Atlantic University and has engaged in graduate studies in
hydrology at Arizona State University. He is registered as a professional geologist in
six states and has more than 10 years of hydrogeological experience. He has directed
numerous projects connected with the study of groundwater, has experience with the
study and remediation of hazardous waste landfills and has performed regulatory
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Robert R. Turton, P.E.
Mr. Turton is a Principal with Golder Construction Services, Inc., where he is
responsible for numerous quality assurance/quality control projects. He holds
Bachelor's and Master's degrees in civil engineering from Queen's University in
Kingston, Ontario, Canada. He has more than 25 years experience with large
construction projects and has been Project Manager for municipal solid waste landfill
design projects in Louisiana, North Carolina and Tennessee. He is registered as a
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
Page No.
1.1 INTRODUCTION 1-1
1.2 MAJOR PROVISIONS OF 40 CFR PART 258 1-2
1.2.1 General (Subpart A) 1-3
1.2.1.1 Purpose, Scope and Applicability 1-3
1.2.1.2 Definitions 1-5
1.2.1.3 Consideration of Other Laws 1-5
1.2.2 Location Restrictions 1-5
1.2.2.1 Airport Safety 1-7
1.2.2.2 Floodplains 1-8
1.2.2.3 Wetlands 1-8
1.2.2.4 Fault Areas 1-8
1.2.2.5 Seismic Impact Zones 1-9
1.2.2.6 Unstable Areas 1-9
1.2.3 Operating Criteria (Subpart C) 1-9
1.2.3.1 Exclusion of Hazardous Waste and PCBs 1-10
1.2.3.2 Daily Cover Requirements 1-10
1.2.3.3 Disease Vector Control 1-11
1.2.3.4 Explosive Gas Control 1-11
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
1.2.3.6 Access and Illegal Dumping Restrictions 1-12
1.2.3.7 Stormwater Run-on/Runoff Control 1-12
1.2.3.8 Surface Water Protection 1-12
1.2.3.9 Liquid Restrictions 1-12
1.2.3.10 Recordkeeping 1-13
1.2.4 Design Criteria (Subpart D) 1-14
1.2.5 Groundwater Monitoring and Corrective
Action (Subpart E) 1-15
1.2.5.1 Groundwater Detection Monitoring Programs .... 1-16
1.2.5.2 Assessment Monitoring Programs 1-18
1.2.5.3 Corrective Action Assessments and
Implementation 1-20
1.2.5.4 Groundwater Monitoring Systems 1-20
1.2.5.5 Sampling and Analysis (Plans and Procedures) . . . 1-21
1.2.5.6 Statistical Procedures 1-22
1.2.5.7 Groundwater Protection Standards 1-23
1.2.5.8 Appendix I 1-24
1.2.5.9 Appendix II 1-24
1.2.6 Closure and Post-Closure Care (Subpart F) 1-24
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
1.2.6.1 Final Cover 1-24
1.2.6.2 Closure Plan 1-25
1.2.6.3 Post-Closure Care Requirements 1-26
1.2.7 Financial Assurance Criteria (Subpart G) 1-27
1.3 CHANGES IN APPLICABILITY AND EFFECTIVE DATES 1-27
1.4 FLEXIBILITY IN APPROVED STATES 1-30
2.1 INTRODUCTION 2-1
2.2 DESIGN CRITERIA 2-1
2.2.1 Design in Unapproved States 2-1
2.2.2 Design in Approved States 2-3
2.3 COMPOSITE LINER DESIGN 2-3
2.3.1 Components of a Composite Liner 2-3
2.3.2 Advantages of a Composite Liner 2-5
2.4 COMPACTED SOIL LINER 2-5
2.4.1 Construction Material 2-5
2.4.2 Construction Objectives 2-7
2.4.2.1 Soil Water Content 2-8
2.4.2.2 Type of Compaction 2-8
2.4.2.3 Compactive Energy 2-12
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
2.4.2.3.1 Weight of the Roller 2-14
2.4.2.3.2 Number of Passes 2-14
2.4.2.3.3 Lift Thickness 2-14
2.4.2.4 Size of Soil Clods 2-14
2.4.2.5 Bonding Between Lifts 2-16
2.5 FLEXIBLE MEMBRANE LINERS 2-20
2.5.1 Types and Thicknesses 2-20
2.5.2 Performance Criteria 2-20
2.5.2.1 Permeability 2-20
2.5.2.2 Chemical Compatibility 2-25
2.5.2.3 Mechanical Compatibility 2-27
2.5.2.4 Durability 2-29
2.5.3 Engineering Properties 2-30
2.5.3.1 Interface Frictional Properties 2-30
2.5.3.2 Allowable Tensile Strength and Strain 2-30
2.5.3.3 Puncture Resistance 2-33
2.5.4 Structural Details 2-33
2.5.4.1 Anchor Trenches 2-33
2.5.4.2 Access Ramps 2-34
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
2.5.4.3 Collection Standpipes 2-34
2.5.5 Mechanisms of Degradation 2-38
2.5.5.1 Ultraviolet Degradation 2-38
2.5.5.2 Chemical Degradation 2-38
2.5.5.3 Extraction Degradation 2-38
2.5.5.4 Oxidation Degradation 2-39
2.5.5.5 Biological Degradation 2-39
2.5.6 Stress-Induced Mechanisms 2-39
2.5.6.1 Creep 2-40
2.5.6.2 Environmental Stress Cracking 2-40
2.5.6.3 Freeze-Thaw Cycle 2-41
2.5.6.4 Abrasion : 2-41
2.6 LEACHATE COLLECTION AND REMOVAL SYSTEM (LCRS) 2-41
2.6.1 Definition and Purpose of LCRS 2-41
2.6.2 Typical LCRS Components 2-43
2.6.2.1 Low-Permeability Base 2-43
2.6.2.2 High-Permeability Drainage Layer 2-44
2.6.2.2.1 Soil Drainage Layers 2-44
2.6.2.2.2 Geosynthetic Drainage Nets 2-45
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
2.6.2.3 Leachate Collection Pipes 2-46
2.6.2.4 Protective Filter Layer 2-50
2.6.2.5 Leachate Collection Sumps 2-51
3.1 INTRODUCTION 3-1
3.2 ELEMENTS OF A CQA PLAN 3-1
3.2.1 Responsibility and Authority 3-1
3.2.2 CQA Personnel Requirements 3-3
3.2.3 Design Specifications 3-3
3.2.4 Inspection Activities 3-3
3.2.5 Sampling Requirements 3-6
3.2.5.1 100-Percent Inspection 3-6
3.2.5.2 Judgmental Sampling 3-8
3.2.5.3 Statistical Sampling 3-9
3.2.6 Acceptance/Rejection Criteria and Corrective Measures 3-9
3.2.7 Documentation 3-10
3.3 CQA FOR SOILS 3-11
3.3.1 Site Preparation 3-13
3.3.2 Subgrade Inspection for Bottom Liner 3-13
3.3.3 Soil Liner Materials Inspection 3-14
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
3.3.4 Placement of Soil Liner 3-16
3.3.5 Compaction of Soil Liner 3-17
3.4 CQA FOR FLEXIBLE MEMBRANE LINERS 3-19
3.4.1 Storage At Site 3-19
3.4.2 Placement of the FML 3-19
3.4.3 FML Field Seams 3-23
3.4.3.1 Solvent Seams 3-25
3.4.3.2 Thermal Seams 3-28
3.4.3.2.1 Hot Air Seaming 3-28
3.4.3.2.2 Hot Wedge Seaming 3-28
3.4.3.2.3 Extrusion Welding 3-31
3.4.4 Seam Tests 3-31
3.4.4.1 Destructive Seam Tests 3-31
3.4.4.2 Nondestructive Seam Tests 3-34
3.4.4.2.1 Air Lance Method 3-38
3.4.4.2.2 Mechanical Point Stress or
"Pick" Test 3-38
3.4.4.2.3 Electric Sparking 3-38
3.4.4.2.4 Pressurized Dual Seam 3-39
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
3.4.4.2.5 Vacuum Chambers 3-39
3.4.4.2.6 Ultrasonic Methods 3-40
3.5 CQA FOR LEACHATE COLLECTION AND RECOVERY SYSTEM 3-40
4.1 INTRODUCTION 4-1
4.2 LANDFILL GAS GENERATION 4-1
4.2.1 Gas Composition 4-2
4.2.2 Gas Characteristics 4-3
4.2.2.1 Methane 4-3
4.2.2.2 Carbon Dioxide 4-3
4.2.2.3 Hydrogen Sulfide 4-4
4.2.3 Gas Generation Phases 4-4
4.2.3.1 Aerobic Decomposition (Phase I) 4-5
4.2.3.2. Anaerobic Non-methanogenic Decomposition
(Phase II) 4-5
4.2.3.3 Anaerobic Methanogenic Decomposition
(Phase III) 4-5
4.2.3.4 Anaerobic (Steady-state) Methanogenesis
(Phase IV) 4-7
4.2.4 Factors Controlling Gas Generation 4-7
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
4.2.4.1 Moisture Content 4-7
4.2.4.2 Organic Content 4-8
4.2.4.3 Temperature and pH 4-8
4.2.4.4 Time Since Waste Placement and Aerobic
Versus Anaerobic Conditions 4-8
4.3 GAS MIGRATION 4-8
4.3.1 Gas Migration Mechanisms 4-8
4.3.2 Factors Affecting Gas Migration 4-9
4.4 GAS DETECTION MONITORING 4-13
4.4.1 Gas Detection Monitoring Program 4-13
4.4.2 Monitoring System Design Factors 4-14
4.4.3 Detection Monitoring Locations 4-15
4.4.3.1 Ambient Conditions 4-15
4.4.3.2 Structures 4-16
4.4.3.3 Subsurface Sampling 4-16
4.4.3.4 Subsurface Gas Monitoring 4-18
4.5 PASSIVE AND ACTIVE GAS MANAGEMENT SYSTEMS 4-19
4.5.1 Passive Gas Management Systems 4-20
4.5.1.1 Open Ditches 4-20
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
4.5.1.2 Vent Trenches 4-20
4.5.1.3 Impermeable Barriers 4-21
4.5.1.4 Vent Layers and Vertical Vents (Wells) 4-21
4.5.1.5 Substructure Vents 4-24
4.5.1.6 Active Gas Management Systems 4-24
4.5.1.7 Extraction Systems (Trenches and/
or Wells) 4-25
4.5.1.8 Injection Barriers 4-28
4.5.1.9 Substructure Extraction 4-28
4.6 GAS MANAGEMENT SYSTEM OPERATION AND MONITORING 4-28
4.6.1 Primary Gas Extraction Well Fields 4-29
4.6.2 Perimeter Gas Migration Control Systems 4-31
5.1 INTRODUCTION 5-1
5.2 REGULATORY REQUIREMENTS 5-1
5.2.1 Minimum Design Requirements 5-1
5.2.2 Alternate Cover Design 5-2
5.2.3 Closure Plan 5-2
5.3 TECHNICAL CONSIDERATIONS 5-4
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
5.4 TYPICAL COMPONENTS OF A FINAL COVER SYSTEM 5-5
5.4.1 Infiltration Layer 5-7
5.4.2 FML Layer 5-8
5.4.3 Drainage Layer 5-10
5.4.4 Erosion Layer 5-13
5.4.5 Optional Layers 5-15
5.4.5.1 Gas Vent Layer 5-15
5.4.5.2 Biotic Layer 5-18
5.5 NATURAL FACTORS AFFECTING FINAL COVER 5-18
5.5.1 Settlement 5-18
5.5.2 Freeze-Thaw Effects 5-20
5.5.3 Desiccation 5-20
5.6 FINAL COVER MONITORING 5-22
5.6.1 Settlement/Subsidence 5-22
5.6.2 Surface Erosion Monitoring or Maintenance 5-24
5.6.3 Air Emissions 5-24
5.7 HELP MODEL 5-25
6.1 INTRODUCTION 6-1
6.2 APPLICABILITY 6-1
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6.3 MSWLF GROUNDWATER MONITORING PROGRAMS 6-2
6.3.1 Detection Monitoring Program 6-2
6.3.2 Assessment Monitoring Program 6-5
6.4 GROUNDWATER MONITORING SYSTEMS 6-8
6.4.1 Requirements for Groundwater Monitoring Systems 6-8
6.4.2 Monitoring Well Performance Standards 6-10
6.4.3 Groundwater Monitoring System Design Considerations 6-11
6.4.4 Monitoring Well Design 6-11
6.4.4.1 Borehole 6-13
6.4.4.2 Well Casing 6-14
6.4.4.3 Sump or Sediment Trap 6-19
6.4.4.4 Well Intake (Screen) 6-19
6.4.4.5 Filter Packs 6-21
6.4.4.5.1 Natural Filter Packs 6-23
6.4.4.5.2 Artificial Filter Packs 6-23
6.4.4.5.3 Filter Pack Placement 6-24
6.4.4.6 Filter Pack And Well Screen Design 6-27
6.4.4.7 Annular Seals 6-28
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6.4.4.7.1 Filter Pack Seal (Bentonite Pellet Seal or
Plug) 6-29
6.4.4.7.2 Annular Grout Seal 6-29
6.4.4.7.3 Bentonite 6-30
6.4.4.7.4 Cement 6-30
6.4.4.8 Surface Seal and Completion 6-32
6.4.4.8.1 Above Grade Completion 6-31
6.4.4.8.2 Flush Completion 6-32
6.4.5 Construction Methods 6-32
6.4.5.1 Drilling Techniques 6-33
6.4.5.1.1 Auger Drilling Methods 6-35
6.4.5.1.1.1 Solid-Stem Auger . . . 6-35
6.4.5.1.1.2 Hollow-Stem Auger .. 6-38
6.4.5.1.2 Rotary Drilling Methods 6-45
6.4.5.1.2.1 Rotary Wash Drilling . 6-45
6.4.5.1.2.2 Air Rotary Drilling ... 6-49
6.4.5.1.2.3 Mud Rotary Drilling . . 6-50
6.4.5.1.3 Other Drilling Methods 6-50
6.4.5.1.4 Cleaning and Decontamination 6-50
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6.4.5.2 Monitoring Well Development 6-50
6.4.5.2.1 Bailing 6-54
6.4.5.2.2 Surging 6-54
6.4.5.2.3 Pumping/Overpumping/Backwashing . 6-56
6.4.5.2.4 Air Lift 6-56
6.4.5.3 Well Construction Documentation 6-57
6.4.5.4 Well Abandonment 6-58
6.4.6 Placement of Monitoring Wells 6-58
6.4.6.1 Hydrogeologic Characterization 6-60
6.4.6.1.1 Existing Information 6-60
6.4.6.1.2 Site-Specific Hydrogeologic lnvestigation6-62
6.4.6.2 Field Observations 6-64
6.4.6.3 Drilling and Materials Testing Programs 6-64
6.4.6.3.1 Boreholes 6-65
6.4.6.3.2 Piezometers 6-65
6.4.6.3.3 Monitoring Wells 6-65
6.4.6.3.4 Materials Testing 6-65
6.4.6.4 Other Characterization Techniques 6-67
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6.4.6.4.1 Data Presentation, Interpretation and
Evaluation 6-67
6.4.6.4.2 Site Location Maps 6-69
6.4.6.4.3 Stratigraphic Cross-Sections and Fence
Diagrams 6-69
6.4.6.4.4 Data Tables and Graphs 6-69
6.4.6.4.5 Potentiometric Maps and Flow Nets . . 6-74
6.4.6.4.6 Narrative Description of Hydrogeology 6-78
6.4.6.4.7 Other Information 6-78
6.4.6.5 Well Location Selection 6-79
6.4.6.6 Groundwater Velocity and Dispersivity 6-80
6.4.6.7 Mounding Effects and Groundwater Reversals . . . 6-85
6.4.6.8 Examples of Monitoring Well Siting Scenarios .... 6-85
6.5 GROUNDWATER SAMPLING AND ANALYTICAL REQUIREMENTS . . . 6-100
6.5.1 Sample Collection 6-100
6.5.1.1 Groundwater Level Measurement 6-103
6.5.1.1.1 Electric Water Level Indicators .... 6-105
6.5.1.1.2 Acoustic Water Level Indicators ... 6-105
6.5.1.1.3 Popper or Bell Sounder 6-105
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MASTER TABLE OF CONTENTS
6.5.1.1.4 Weighted Tape 6-105
6.5.1.1.5 Chalked Tape 6-105
6.5.1.1.6 Other Methods 6-107
6.5.1.2 Purging 6-107
6.5.1.3 Sampling Equipment Decontamination 6-107
6.5.1.4 Sampling Procedures 6-109
6.5.1.5 Filtering 6-109
6.5.2 Sample Preservation and Shipment 6-113
6.5.3 Chain-of-Custody 6-114
6.5.4 Analytical Procedures 6-115
6.5.5 Quality Assurance/Quality Control 6-115
6.5.6 Statistical Evaluations 6-117
6.5.6.1 Parametric ANOVA 6-119
6.5.6.2 ANOVA Based on Ranks 6-119
6.5.6.3 Tolerance or Prediction Intervals 6-119
6.5.6.4 Control Chart 6-120
6.5.6.5 Other Statistical Methods 6-120
6.5.7 Groundwater Protection Standards 6-120
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6.6 CONTAMINANT FATE AND TRANSPORT PROCESSES 6-120
6.6.1 Physical Processes 6-121
6.6.1.1 Advection 6-121
6.6.1.2 Dispersion 6-121
6.6.1.3 Diffusion 6-124
6.6.1.4 Retardation 6-124
6.6.2 Chemical Processes 6-124
6.6.2.1 Sorption 6-125
6.6.2.2 Dissolution/Precipitation 6-125
6.6.2.3 Acid-Base Reactions 6-125
6.6.2.4 Complexation 6-125
6.6.2.5 Hydrolysis/Substitution 6-126
6.6.2.6 Redox Reactions 6-126
6.6.2.7 Radioactive Decay 6-126
6.6.3 Biological Processes 6-126
6.6.4 Nonaqueous-Phase Liquids 6-127
6.6.4.1 Light Nonaqueous-Phase Liquids 6-127
6.6.4.2 Dense Nonaqueous-Phase Liquids 6-130
6.6.5 Delineation of Extent of Contamination/Additional Monitoring 6-132
7.1 CORRECTIVE ACTION AS END RESULT 7-1
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
List of Figures: Page No.
1-1 Decision Tree for the Applicability of 40 CFR 258 1-4
1-2 Location Restrictions (Subpart B) 1-6
Summary of Changes to the Effective Dates of the
1-3 MSWLF Criteria 1-28
2-1 Composite Liner Components 2-2
2-2 Maximum Groundwater Concentrations at POC 2-4
2-3 Leachate Infiltration: Clay vs. Composite Liner 2-6
2-4 Hydraulic Conductivity and Dry Unit Weight as a
Function of Molding Water Content 2-9
2-5 a-b Compaction Equipment Guidance 2-10 thru 2-11
2-6 Effects of Compactive Effort on Maximum
Density and Hydraulic Conductivity 2-13
2-7 Effects of Soil Clod Size on Hydraulic Conductivity 2-15
2-8 Conductivity Between Lifts 2-17
2-9 Footed Rollers With Partly and Fully Penetrating Feet .... 2-18
2-10 Liner Construction on Side Slopes With Horizontal and
Parallel Lifts 2-19
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
Some Advantages and Disadvantages of the Basic
Polymers of Geomembranes 2-21 thru 2-24
Flexible Liner Evaluation Expert (FLEX) 2-28
Typical Range of Interface Friction Angles 2-31
Typical Mechanical Properties 2-32
Various Types of Geomembrane Anchor Trenches 2-35
Typical Access Ramp Geometry and Cross Section 2-36
Leachate Removal System With a High Volume Sump . . . 2-37
Sources of Leachate Generated by a Solid Waste
(Flowchart) 2-42
Definition of Terms for Mound Model Flow Rate
Calculations 2-48
Recommendations For Construction of
Clay-Lined Landfills 3-7
Method for Testing Low-Permeability Soil Liners 3-12
Photographs of Temporary Storage of Geotextiles 3-20
Deployment of the Geomembrane 3-21
Photographs Showing the Unrolling and Unfolding
of Geomembranes 3-22
Wind Damage to Deployed Geomembrane 3-24
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
3-7 Field Seaming Techniques for Geomembranes 3-26
3-8 Photographs of Geomembrane Being Bonded 3-27
3-9 Cross Section of Automated Machine-Driven Hot Air
Seaming Device for Geomembranes 3-29
3-10 The Hot Wedge System 3-30
3-11 The Extrusion Welding System 3-32
3-12 Destructive Seam Tests 3-34
3-13a Overview of Nondestructive Seam Tests 3-35
3-13b Overview of Nondestructive Seam Tests 3-36
4-1 Evolution of Typical Landfill Gas Composition 4-6
4-2 Vertical and Lateral Migration 4-10
4-3 Landfill Migration Pathways 4-12
4-4 Typical Landfill Gas Monitoring Well/Probe 4-17
4-5 Typical Passive Vent Layer Gas Management System .... 4-22
4-6 Vent Layers and Vertical Vents (Wells) 4-23
4-7 Typical Gas Extraction Well 4-26
4-8 Typical Gas Extraction Trench and Header 4-27
4-9 Typical Primary Gas Extraction Wellfield System 4-30
5-1 Minimum Final Cover Design 5-3
5-2 Typical Final Cover Design 5-6
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5-3 Drainage Layer Options 5-12
5-4 Final Cover Design With Optional Layers 5-16
5-5 Gas Vent Layer 5-17
5-6 Biotic Intrusion 5-19
5-7 Regional Depth of Frost Penetration 5-21
5-8 Threshold Limit Values of Selected Air Contaminants .... 5-24
5-9 Typical Output Data 5-26
6-1 Flow Chart of Detection Monitoring Program 6-3
6-2 Flow Chart of Assessment Monitoring Program 6-6
6-3 Comparison of Single Unit and Multiunit Monitoring Systems 6-9
6-4 Diagram of Typical Monitoring Well Construction 6-12
6-5 Forces Exerted on Monitoring Well Materials 6-16
6-6 Types of Well Casing Joints 6-18
6-7 Types of Well Intakes (Screens) 6-20
6-8 Envelope of Coarse-Grained Material Around
Well Screen (Filter Pack) 6-22
6-9 Tremie Pipe Emplacement of Artificial Filter Pack
Materials 6-25
6-10 Free Fall Method of Filter Pack Emplacement With
a Hollow-Stem Auger 6-26
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6-11 Drilling Methods for Various Types of Geologic Settings . . 6-34
6-12 Diagram of a Solid-Stem Auger 6-36
6-13 Applications and Limitations of Solid-Stem Augers 6-37
6-14 Diagram of a Hollow-Stem Auger 6-39
6-15 Applications and Limitations of Hollow-Stem Augers .... 6-40
6-16 Sequential Steps in Hollow-Stem Drilling and Sampling . . . 6-41
6-17 Flexible Center Plug in Hollow-Stem Auger Bit 6-42
6-18 Hollow-Stem Auger With Pilot-Bit Assembly 6-43
6-19 Hollow-Stem Auger With Knock-Out Bottom Plug 6-44
6-20 Diagram of a Direct Rotary Drilling System 6-46
6-21 Applications and Limitations of Direct Mud Rotary Drilling . 6-47
6-22 Applications and Limitations of Air Rotary Drilling 6-48
6-23 Diagram of a Cable Tool Drilling System 6-51
6-24 Applications and Limitations of Cable Tool Drilling 6-52
6-25 Diagram of a Typical Surge Block 6-55
6-26 Factors Influencing the Density of Borholes 6-66
6-27 Summary of Hydrogeologic Investigation Techniques .... 6-68
6-28a, b Summary of Other Data Presentation and Interpretation
Techniques 6-70
6-29 Simple Geologic Cross-section 6-72
-------
SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6-30 Typical Fence Diagram 6-73
6-31 Typical Potentiometric Map 6-75
6-32 Interpolating Potentiometric Data 6-76
6-33 Typical Flow Net 6-77
6-34 Factors Influencing Well Spacing 6-81
6-35 Factors Influencing Number of Wells per Location 6-82
6-36 Contaminant Migration in High and Low Velocity
Groundwater Settings 6-83
6-37 Contaminant Migration in High and Low Transverse
Dispersivity Settings 6-84
6-38 Mounding Effects on Contamiant Migration 6-86
6-39 Monitoring System for Simple Geologic Setting 6-87
6-40 Monitoring System for Complex Geologic Setting 6-88
6-41 Monitoring System for Karst Geology 6-89
6-42 Contaminant Migration-Scenario 1 6-90
6-43 Contaminant Migration-Scenario 2 6-91
6-44 Contaminant Migration-Scenario 3 6-92
6-45 Contaminant Migration-Scenario 4 6-93
6-46 Contaminant Migration-Scenario 5 6-94
6-47 Contaminant Migration-Scenario 6 6-95
-------
SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
6-48 Contaminant Migration-Scenario 7 6-96
6-49 Contaminant Migration-Scenario 8 6-97
6-50 Contaminant Migration-Scenario 8 (Surface View) 6-98
6-51 Contaminant Migration-Scenario 9 6-99
6-52 Generalized Flow Diagram of Groundwater Sampling
Steps 6-102
6-53 Typical Electric Water Level Indicator 6-106
6-54 Typical Sampling Bailer 6-110
6-55 Typical Bladder Pump 6-111
6-56 Typical Vaccum Bottle Sample Collection Method 6-112
6-57 Aqueous Phase Contaminant Fate and Transport
Process 6-122
6-58 Dispersion in a Porous Media 6-123
6-59 Non Aqueous Phase Liquids 6-128
6-60 Movement of LNAPLs into the Subsurface 6-129
6-61 Movement of DNAPLs into the Subsurface 6-131
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SUBTITLE D TECHNICAL TRAINING MANUAL
MASTER TABLE OF CONTENTS
ATTACHMENTS:
Attachment A "Flexible Membrane Liners," by Gregory N. Richardson
Attachment B Method 9090, Compatibility Test for Wastes and Membrane
Liners
Attachment C
Attachment D
Attachment E
Attachment
Observations and Tests for the Construction Quality Assurance and
Quality Control of Hazardous Waste Disposal Facilities
Solid Waste Disposal Facility Criteria Final Rule; Corrections
Solid Waste Disposal Facility Criteria; Delay of Compliance and
Effective Dates
Attachment F Solid Waste Disposal Criteria Delay of the Effective Date
Attachment G 40 CFR 257; 40 CFR 258
Attachment H RCRA Section 4005, 42 U.S.C. 6945
Clean Water Act, Section 208, 33 U.S.C. 1288
Attachment J Clean Water Act, Section 319, 33 U.S.C. 1329
Attachment K Clean Water Act, Section 402, 33 U.S.C. 1342
Attachment L Clean Water Act, Section 404, 33 U.S.C. 1344
Attachment M Report of Workshop on Geosynthetic Clay Liners
Attachment N Technical Tips, Bulletin #101, Landfill Fires
Attachment 0 Technical Tips, Bulletin #103, Health and Safety
-------
SUBTITLE D TECHNICAL TRAINING MANUAL
Introduction
The purpose of this manual is to assist regulatory personnel in understanding the
technical aspects of planning and implementing regulatory programs for munici-
pal solid waste landfill managementwhich are equivalent to or exceed the Federal
requirements. The manual addresses the following provisions of the RCRA
Subtitle D regulations:
Design (Liner and Leachate Collection and Recovery System)
Landfill Gas Monitoring and Management
Final Cover
Groundwater Monitoring
This manual is intended to convey a working knowledge of the topics covered.
More in-depth training may be necessary for developing expertise in any one of
the areas covered.
I
-------
SUBTITLE B TECHNICAL TRAINING MANUAL
-------
-------
SECTION 1.0
General Overview of Municipal Solid Waste Landfill Criteria
Page No.
1.1 INTRODUCTION 1-1
1.2 MAJOR PROVISIONS OF 40 CFR PART 258 1-2
1.2.1 General (Subpart A) 1-3
1.2.1.1 Purpose, Scope and Applicability 1-3
1.2.1.2 Definitions 1-5
1.2.1.3 Consideration of Other Laws 1-5
1.2.2 Location Restrictions 1-5
1.2.2.1 Airport Safety 1-7
1.2.2.2 Floodplains 1-8
1.2.2.3 Wetlands 1-8
1.2.2.4 Fault Areas 1-8
1.2.2.5 Seismic Impact Zones 1-9
1.2.2.6 Unstable Areas 1-9
1.2.3 Operating Criteria (Subpart C) 1-9
1.2.3.1 Exclusion of Hazardous Waste and PCBs 1-10
1.2.3.2 Daily Cover Requirements 1-10
1.2.3.3 Disease Vector Control 1-11
-------
1.2.3.5 Air Emissions Control 1-12
1.2.3.6 Access and Illegal Dumping Restrictions 1-12
1.2.3.7 Stormwater Run-on/Runoff Control 1-12
1.2.3.8 Surface Water Protection 1-12
1.2.3.9 Liquid Restrictions 1-12
1.2.3.10 Recordkeeping 1-13
1.2.4 Design Criteria (Subpart D) 1-14
1.2.5 Groundwater Monitoring and
Corrective Action (Subpart E) 1-15
1.2.5.1 Groundwater Detection Monitoring Programs 1-16
1.2.5.2 Assessment Monitoring Programs 1-18
1.2.5.3 Corrective Action Assessments and
Implementation 1-20
1.2.5.4 Groundwater Monitoring Systems 1-20
1.2.5.5 Sampling and Analysis (Plans and Procedures) 1-21
1.2.5.6 Statistical Procedures 1-22
1.2.5.7 Groundwater Protection Standards 1-23
1.2.5.8 Appendix I 1-24
1.2.5.9 Appendix II 1-24
1.2.6 Closure and Post-Closure Care (Subpart F) 1-24
1.2.6.1 Final Cover 1-24
1.2.6.2 Closure Plan 1-25
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1.2.6.3 Post-Closure Care Requirements 1-26
1.2.7 Financial Assurance Criteria (Subpart G) 1-27
1.3 CHANGES IN APPLICABILITY AND EFFECTIVE DATES 1-27
1.4 FLEXIBILITY IN APPROVED STATES 1-30
REFERENCES 1-34
List of Figures: Page No.
1-1 Decision Tree for the Applicability of 40 CFR 258 1-4
1-2 Location Restrictions (Subpart B) 1-6
Summary of Changes to the Effective Dates of the
1-3 MSWLF Criteria 1-28
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
1.1 Subtitle D of the Resource Conservation and Re-
INTRODUCTION covery Act (RCRA) directed the Environmental Pro-
tection Agency (EPA) to develop a regulatory
program governing the disposal of solid waste. In
response, EPA issued regulations for Municipal
Solid Waste Landfills (MSWLFs), found in Title 40,
Code of Federal Regulations (CFR) Part 258. This
section reviews the major provisions of those regu-
lations, referred to as the Subtitle D Regulations.
40 CFR Part 258
Subpart A -
General Requirements
Subpart B -
Location Restrictions
Subpart C -
Operating Criteria
Subpart D -
Design Criteria
Subpart E -
Groundwater Monitoring
and Corrective Action
Subpart F -
Closure and Post-
Closure Care
Subpart G -
Financial Assurance
Criteria
Appendix I -
Constituents for
Detection Monitoring
Appendix II -
List of Hazardous and
Organic Constituents (for
Assessment Monitoring)
This section also provides general discussions of
the flexibility available to EPA- approved state
programs.
1-1
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SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
1.2
MAJOR PROVISIONS
OF 40 CFR PART 258
The Subtitle D regulations for MSWLFs establish mini-
mum Federal standards that specifically address the
following:
Purpose, scope and applicability of the
regulations (Subpart A),
Definitions (Subpart A);
Consideration of other laws (Subpart A);
Location restrictions for facility siting
and/or continued operation (Subpart B);
Operating requirements (Subpart C);
Liner and leachate collection system de-
sign (Subpart D);
Groundwater monitoring (Subpart E);
Groundwater corrective action (Subpart
E);
Closure and post-closure care (Subpart
F); and
Financial assurance (Subpart G).
The following paragraphs briefly discuss topics
covered by the Subtitle D regulations. States
must adopt and implement MSWLF regulatory
(permit) programs with standards at least as strin-
gent as EPA's; otherwise, the Federal regula-
1-2
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
tions establish the minimum standards for
MSWLFs.
1.2.1
Subpart A describes the purpose, scope and
General (Subpart A)
applicability of the Subtitle D regulations, pro-
vides definitions of terms used throughout the
regulations and addresses facility responsibility
for compliance with other applicable rules, laws,
regulations or other requirements.
1.2.1.1
The purpose of these regulations is to provide
Purpose, Scope and
for protection of human health and the environ-
Applicability
ment by establishing minimum national solid
waste disposal criteria for:
MSWLF units used to dispose of munici-
pal solid waste under RCRA
MSWLF units used to dispose of sewage
sludge under the Clean Water Act (CWA)
The Subtitle D regulations apply to new and ex-
isting MSWLF units as well as lateral expansions
of existing MSWLFs. New MSWLF units are
those that did not receive waste prior to October
9, 1993. Existing MSWLF units, on the other
hand, are those that were receiving solid waste
as of October 9, 1993 (Figure 1 -1).
MSWLF units that did not receive waste after Octo-
ber 9,1991, are exempt from the EPA Subtitle D
regulations, while MSWLF units that received
waste after October 9, 1991, but stopped receiving
waste before October 9, 1993, are exempt from all
of the EPA Subtitle D regulations except for those
pertaining to installation of final cover. Those
MSWLF units that fail to complete cover installation
within the prescribed period (see Section 1.3 -
1-3
-------
Decision Tree for the Applicability of
40 CFR Part 258
O
$
Cfi
&
O,
5?
CD
S-
3
ง'
3
3'
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
"Changes in Effective Dates") are subject to all
of the Subtitle D requirements.
All other solid waste disposal facilities and prac-
tices that are not regulated under RCRA Subtitle
D or Subtitle C (Hazardous Waste Regulations)
are subject to the standards contained in 40
CFR Part 257, Criteria for Classification of Solid
Waste Disposal Facilities and Practices.
1.2.1.2 General definitions used throughout the regula-
Definitions tions are included in Section 258.2 of the regula-
tions while other sections contain
subject-specific definitions.
1.2.1.3 The EPA Subtitle D regulations specifically provide
Consideration of Other that all MSWLF units must comply not only with
Laws these criteria but with any other applicable Federal
rules, laws, regulations or other requirements as
well. This general statement covers all other Federal
programs which are not specifically referenced in 40
CFR Part 258. Compliance with state and local re-
quirements are not specifically addressed under the
Federal criteria and therefore remain under the ap-
propriate jurisdictions. However, the Federal criteria
do not imply that MSWLFs are exempt from such
state and local requirements.
1.2.2 Because of potential impacts from MSWLFs, the
Location Restrictions EPA regulations contain location restriction crite-
ria for the following six areas of concern (Figure
1-2):
Airport safety
Floodplains
Wetlands
1-5
-------
Location Restrictions (Subpart B)
Restricted
Location
Applies
to
Existing
Units
Applies to
New Units
and Lateral
Expansions
Make Demonstration to
Director of an
Approved State/Tribe
and Retain
Demonstration in
Operating Record
Existing Units
Must Close if
Demonstration
Cannot be
Made
Airport
Yes
Yes
Yes
Yes
Floodplains
Yes
Yes
Yes
Yes
Wetlands
No
Yes
Yes
N/A
Fault Areas
No
Yes
Yes
N/A
Seismic Impact
Zones
No
Yes
Yes
N/A
Unstable Areas
Yes
Yes
Yes
Yes
Figure 1-2
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Fault Areas
Seismic impact zones
Unstable areas
Owners and operators of new and lateral expan-
sions of existing MSWLFs must demonstrate
compliance with all six location restriction criteria
before construction and operation can begin.
Owners and operators of existing facilities must
demonstrate compliance with only three of the
criteria: airport safety, floodplains and unstable
areas. Existing facilities that cannot demonstrate
compliance with these three criteria must close
by October 9, 1996, unless an extension is pro-
vided by the Director of an EPA-approved State.
Demonstrations of compliance must be included
in the Operating Record and reported to EPA or
the Director of an approved State.
1.2.2.1 The airport safety demonstration must show that
Airport Safety the MSWLF is designed and operated so as not
to pose a bird hazard to aircraft, if the facility is:
Located within 10,000 feet of an airport
runway used by turbojet aircraft, or
Located within 5,000 feet of an airport
runway used only by piston-type aircraft.
The Federal Aviation Administration must
also be notified if the MSWLF is located
within 5 miles of an airport.
1-7
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SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
1.2.2.2
Floodplains
If the MSWLF is located in a 100-year floodplain,
the floodplain demonstration must show that the
facility will not:
Restrict the flow of the 100-year flood
Reduce the temporary water storage ca-
pacity of the floodplain
Result in washout of solid waste so as to pose
a hazard to human health and the environment
1.2.2.3
Wetlands
New MSWLF units and lateral expansions of exist-
ing units may not be located in wetlands without an
appropriate demonstration by the facility owner or
operator to the Director of an approved State. Such
a demonstration must show that:
No practical alternative to a wetland is
available;
No violation of State water quality stand-
ards or CWA toxic effluent standards,
jeopardy for threatened or endangered
species or critical habitat under the En-
dangered Species Act or violation of Ma-
rine Sanctuaries Act requirements will
occur;
There will be no degradation of the wet-
land and its ecological resources; and
Steps have been taken to achieve no net
loss of wetlands.
1,2-2.4
Fault Areas
The fault area demonstration must show that the
MSWLF is not located within 200 feet of a fault
that has had displacement in Holocene time, or,
if allowed in EPA-approved state programs, that
1-8
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
the facility is designed in a manner such that an
alternative setback distance of less than 200 feet
will prevent damage to the structural integrity of
the MSWLF unit and will be protective of human
health and the environment.
1.2.2.5
The seismic impact zone demonstration must
Seismic Impact Zones
show that the MSWLF is not located in a seismic
impact zone or, if allowed in EPA-approved state
programs, demonstrate that all containment
structures, including liners, leachate collection
systems and surface water control systems are
designed to resist the maximum horizontal accel-
eration in lithified earth material for the site.
1.2.2.6
If the MSWLF is located in an unstable area, the
Unstable Areas
unstable area demonstration must show that en-
gineering measures have been incorporated into
the design to ensure that the integrity of the
structural components will not be disrupted.
1.2.3
Owners and operators of all new, existing and lat-
Operating Criteria
eral expansions of MSWLFs must implement oper-
(Subpart C)
ating procedures to address the following criteria:
Exclusion of hazardous waste and poly-
chlorinated biphenyls (PCBs)
Daily cover requirements
Disease vector control
Explosive gas control
Air emissions control
Access and illegal dumping restrictions
Stormwater run-on/runoff control
1-9
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SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
Surface water protection
Liquid disposal restrictions
Recordkeeping requirements
1.2.3.1 A program must be implemented to detect and
Exclusion of Hazardous prevent disposal of regulated hazardous waste
Waste and PCBs as defined in 40 CFR Part 261 and PCBs as de-
fined in 40 CFR Part 761.
The hazardous waste exclusion program must in-
clude the following:
Random inspections of incoming loads
or other steps to prevent acceptance of
regulated hazardous wastes or PCB
wastes.
Records of inspections.
Training of facility personnel to recognize
regulated hazardous waste and PCB
wastes.
Procedures for notifying the appropriate
authority (EPA or a Subtitle C authorized
State) if a restricted waste (regulated
hazardous waste or PCB waste) is dis-
covered.
1.2.3.2 Daily cover must be applied to the exposed
Daily Cover Requirements waste at the end of each operating day, or more
frequently if necessary, to prevent or control on-
site populations of disease vectors, fires, odors,
blowing litter and scavenging. The minimum
daily cover requirement is 6 inches of earthen
material. However, the use of alternative cover
1-10
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
materials may be allowed by Directors of EPA-
approved state programs.
1.2.3.3
Appropriate means must be used to prevent or
Disease Vector Control
control onsite populations of disease vectors.
1.2.3.4
A program must be implemented for routinely moni-
Explosive Gas Control
toring (not less frequently than quarterly) and control-
ling methane gas accumulation and migration so
that the methane concentrations:
Do not exceed 25 percent of the Lower
Explosive Limit (LEL) in onsite structures
(1.25 percent in air); and
Do not exceed the LEL at the site bound-
ary (5 percent in air).
If methane gas levels exceed these limits, the fol-
lowing actions must be undertaken:
Immediately - Take all necessary steps
to ensure protection of human health.
Notify the appropriate regulatory author-
ity (EPA and/or approved state agency.)
Within 7 days - Place the methane gas
levels detected and a description of the
steps taken to protect human health in
the operating record.
Within 60 days - Implement a remediation
plan for the methane gas releases, place a
copy of the plan in the operating record
and notify EPA and/or the State Director
that the remediation plan has been imple-
mented.
1-11
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
1.2.3.5
Open burning is prohibited, except for the infre-
Air Emissions Control
quent burning of agricultural wastes, land-clear-
ing debris, diseased trees or debris from
emergency cleanup operations.
The MSWLF must also comply with the State Im-
plementation Plan developed under the Clean
Air Act.
1.2.3.6
Access to the MSWLF must be controlled to pre-
Access and Illegal Dumping
vent unauthorized traffic and prevent illegal
Restrictions
dumping. Access may be controlled by artificial
barriers, natural barriers or both, as appropriate.
1.2.3.7
The MSWLF must have a plan to design, con-
Stormwater Run-on/Runoff
struct and maintain a run-on/runoff control sys-
Control
tem to:
Prevent run-on to the active area from
the peak discharge of a 25-year storm,
and
Collect and control runoff from the active
area resulting from a 24-hour, 25-year
storm.
1.2.3.8
Discharges of pollutants and nonpoint sources of
Surface Water Protection
pollution that enter waters of the United States
(including wetlands) that violate any requirement
of the Clean Water Act and any areawide or
statewide water quality management plans must
be prevented.
1.2.3.9
No bulk or noncontainerized liquid waste may be
Liquid Restrictions
placed in MSWLFs. Normal household liquid
wastes and liquid wastes in small containers
(similar in size to that normally found in house-
hold waste and designed for holding liquids for
use and not storage) may be placed in MSWLFs.
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Leachate or gas condensate may be placed in
the MSWLF unit, but only if the facility is con-
structed with a composite liner and leachate col-
lection system and the leachate or condensate
was derived from the MSWLF.
1.2.3.10
The following records, at a minimum, must be re-
Recordkeeping
tained in an operating record which must be lo-
cated at or near the facility:
Location restriction demonstrations;
Waste exclusion program inspection re-
cords, training and notification proce-
dures;
Gas monitoring results and any required
remediation plans;
Design documentation for placement of
leachate or gas condensate in the landfill,
Groundwater demonstrations, certifica-
tions, findings and any monitoring, test-
ing or analytical data;
Closure and post-closure care plans and
any required monitoring, testing or ana-
lytical data (including groundwater, land-
fill gas and testing or analytical data
required for post closure care); and
Financial assurance cost estimates and
documentation.
Notification of placement of these documents in
the operating record must be provided to the ap-
propriate state regulatory authority. Copies of all
information contained in the operating record
1-13
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SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
must be furnished to the state regulatory author-
ity (as requested) or be made available for in-
spection by state agency representatives at all
reasonable times.
1.2.4 New MSWLF units and lateral expansions must
Design Criteria be designed with a two-component composite
(Subpart D) liner that cons'sts of the following:
Lower component - A minimum of 2 feet
of soil material compacted to a hydraulic
conductivity of no more than 1 x 1CT7 cen-
timeters/second (cm/sec).
Upper component - A minimum 30-mil
flexible membrane liner (FML) installed
in direct and uniform contact with the
lower component. If high-density polyeth-
ylene (HDPE) is used, a minimum thick-
ness of 60 mils is required.
A leachate collection system which is de-
signed and constructed to maintain less
than a 30-cm (approximately 1-foot)
depth of leachate over the liner.
Alternative engineering designs may be allowed
by Directors of approved States provided the de-
signs prevent release of Table 1 constituents at
concentrations exceeding the Maximum Contami-
nant Levels (MCLs) in the uppermost aquifer at
the point of compliance. The point of compliance
is the waste management unit boundary or as
close as site features allow. Alternative point of
compliance distances, up to 150 meters from the
waste management unit boundary and on land
owned by the owner of the MSWLF unit, may be
allowed in EPA-approved state programs.
1-14
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
UUl
Groundwater Monitoring
and Corrective Action
(Subpart E)
The EPA Subtitle D regulations include an exten-
sive set of groundwater monitoring and correc-
tive action requirements which apply to new,
existing and lateral expansions of existing
MSWLF units. The three principal components of
the groundwater requirements are:
Detection Monitoring Program - Back-
ground concentrations of specific con-
stituents (listed in Part 258, Appendix I)
must be established and used to evalu-
ate groundwater monitoring data, which
is collected semiannually to determine if
a statistically significant increase (SSI)
has occurred from the MSWLF. Detec-
tion monitoring must be performed
throughout the active life, closure and
post-closure care periods of the MSWLF.
Assessment Monitoring Programs -
Additional evaluations of impacts to
groundwater quality must be performed
for the hazardous constituents listed in
Part 258, Appendix II whenever a SSI
over background is detected for one or
more of the detection monitoring constitu-
ents.
Corrective Action Assessments and Im-
plementation - Potential remedies must be
evaluated and implemented if any Part 258,
Appendix II constituents are detected above
groundwater protection standards. Ground-
water protection standards must be estab-
lished for any Appendix II constituents
detected in groundwater.
The regulations also discuss the minimum crite-
ria for:
1-15
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Groundwater monitoring systems
Groundwater sampling and analysis
(plans and procedures)
Statistical procedures
Groundwater protection standards
1.2,5.1
A detection monitoring program must be estab-
Groundwater Detection
lished that includes semiannual monitoring for
Monitoring Programs
the Appendix I constituents at background and
point of compliance locations. EPA approved
state programs may contain provisions for the fol-
lowing:
Suspending groundwater monitoring
where it can be demonstrated that there
is no potential for migration of hazardous
constituents from the MSWLF unit to the
uppermost aquifer.
Identifying an alternative (shorter) list of
detection monitoring parameters if it can
be shown that any deleted constituents
are not expected to be contained in or de-
rived from the waste.
Designating an alternative frequency for
detection monitoring. The alternative
monitoring frequency must be no less
than annual.
Designating an alternative distance for lo-
cating point of compliance monitoring
wells. The alternative point of compli-
ance distance must be no greater than
150 meters from the waste management
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SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
unit boundary and on land owned by the
owner of the MSWLF unit.
Once established, the groundwater detection
monitoring program, including all system compo-
nents (i.e., wells, piezometers or other measure-
ment, sampling and analytical devices) must be
conducted, operated and maintained in accord-
ance with the design specifications throughout
the MSWLF's active life and post-closure care
period.
Within a reasonable period of time after complet-
ing each sampling and analysis, the groundwater
monitoring data must be evaluated to determine
whether or not there is a SSI over background
values for each of the detection monitoring con-
stituents.
In order to perform the statistical evaluations,
background groundwater quality must be estab-
lished for each of the monitoring constituents.
Background groundwater quality data may be de-
rived from locations that are either hydraulically
upgradient from the MSWLF unit or at other loca-
tions that provide more representative back-
ground data.
Groundwater data collected from the point of
compliance (detection monitoring wells) must be
compared against the background data to deter-
mine if there is a SSI at any of the compliance
monitoring wells. Within 14 days of determining
that a SSI of one or more detection monitoring
constituents has occurred, the State regulatory
authority must be notified that the results have
been placed in the operating record. An assess-
ment monitoring program must be implemented
within 90 days, unless it can be demonstrated
1-17
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SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
1.2.5.2
Assessment Monitoring
Programs
that another source caused the contamination or
that the SSI resulted from errors in sampling,
analysis, statistical evaluation or natural variation
in groundwater quality.
Assessment monitoring is required whenever a
SSI over background has been detected for one
or more of the detection monitoring constituents.
The assessment monitoring program requires
that:
Within 90 days of triggering the assess-
ment monitoring program, and annually
thereafter, groundwater must be ana-
lyzed for all of the Appendix II constitu-
ents. For any constituent detected in the
downgradient wells as the result of the
complete Appendix II analysis, a suffi-
cient number of independent samples
must be collected and analyzed for each
well (background and downgradient) to
establish background and provide for sta-
tistical evaluation of the new constitu-
ents. Within 14 days after obtaining the
analytical results, the state regulatory
authority must be notified that informa-
tion on the Appendix II constituents that
have been detected has been placed in
the operating record.
Within 90 days, and at least semiannu-
ally thereafter, groundwater must be re-
sampled for the detection monitoring
parameters (Appendix I or alternative list)
and for detected Appendix II constituents.
Groundwater protection standards must
also be established for all detected Ap-
pendix II constituents.
1-18
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Statistical evaluations must be conducted to de-
termine if the detected constituents are above
background and above or below the groundwa-
ter protection standards. If the concentrations of
Appendix II constituents are:
At or below background values for two
consecutive sampling events, then the
owner or operator of the MSWLF must
notify the State Director and may return
to detection monitoring.
Above background values but below the
groundwater protection standard, then
the MSWLF owner or operator must con-
tinue assessment monitoring.
Above the groundwater protection stand-
ard, then the MSWLF owner or operator
must, within 14 days, notify the state
regulatory agency and all appropriate lo-
cal government officials that the informa-
tion about Appendix II constituents which
have exceeded the groundwater protec-
tion standard has been placed in the op-
erating record.
Discovery of Appendix II constituents at concen-
trations above groundwater protection standards
triggers additional requirements for the owner or
operator, who must in addition to the steps de-
scribed above:
Characterize the nature and extent of the
release by installing and sampling other
additional monitoring wells as necessary.
Install and sample at least one additional
monitoring well located at the facility
1-19
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
boundary in the direction of contaminant
migration.
Notify all persons who own or reside on
land that directly overlies any part of a
groundwater contamination plume that
has migrated offsite.
Initiate an assessment of corrective
measures within 90 days or demonstrate
that another source caused the contami-
nation, or that the SSI resulted from error
in sampling, analysis, statistical evalu-
ation or natural variation in groundwater
quality.
1.2.5.3
The corrective action assessment and implemen-
Corrective Action
tation program requires evaluation of potential re-
Assessments and
medial alternatives and selection of an
Implementation
appropriate and acceptable remedy. This pro-
gram requires in-depth evaluation of site condi-
tions, contaminant releases and remedial
technologies. Public participation in the selection
process is also required. The details of this pro-
gram are complex and can best be compared to
similar programs under CERCLA (Remedial In-
vestigation and Feasibility Study Program) and
RCRA (RCRA Facility Investigation Program.)
1.2.5.4
The groundwater detection monitoring system
Groundwater
must consists of a sufficient number of wells, in-
Monitoring Systems
stalled at appropriate locations and depths to
yield groundwater samples from the uppermost
aquifer that:
Represent the quality of background
groundwater that has not been affected
by leakage from a waste management
unit; and
1-20
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
1.2.5.5
Sampling and Analysis
(Plans and Procedures)
Represent the quality of groundwater
passing the relevant point of compliance
or at the waste management unit bound-
ary.
Multiunit groundwater monitoring systems in-
stead of separate groundwater monitoring sys-
tems for each MSWLF unit may be allowed in
EPA approved state programs.
The groundwater monitoring program must in-
clude detailed procedures and techniques for:
Sample collection
Sample preservation and shipment
Analytical procedures
Chain of custody control
Quality assurance and quality control
The groundwater monitoring plans and proce-
dures must:
Provide for measurement of groundwa-
ter elevations immediately prior to purg-
ing (for determining purge volumes).
Provide for measurement of water levels
in all wells within a period of time short
enough to avoid temporal variations
(which could preclude accurate determi-
nation of groundwater flow rate and direc-
tion).
1-21
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
Provide for determination of the rate and
direction of groundwater flow each time
groundwater is sampled
Include procedures that are appropriate
for analysis of groundwater quality.
Include procedures that ensure results that
accurately represent groundwater quality
(i.e., hazardous constituent concentrations
and other monitoring parameters).
Disallow field filtering of samples prior to
laboratory analysis.
Identify the statistical method(s) that will
be used in evaluating groundwater moni-
toring data for each constituent in each
well.
Provide for collection of a sufficient num-
ber of samples to establish groundwater
quality data and accurately perform the
statistical procedure(s).
1.2.5.6 EPA has identified the following statistical meth-
Statistical Procedures ods that are applicable to evaluation of ground-
water data collected at RCRA facilities:
Parametric ANOVA
ANOVA
Tolerance or Prediction Intervals
Control Chart
Other Statistical Methods
1-22
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
The statistical method must, if necessary, in-
clude procedures to control or correct for sea-
sonal and spatial variability as well as temporal
correlation in the data.
The statistical method must be appropriate for
the distribution of chemical parameters or haz-
ardous constituents. If the distribution of the
chemical parameters or hazardous constituents
is inappropriate for a normal theory test, the data
should be transformed or a distribution-free the-
ory test should be used. If the distributions for
the constituents differ, more than one statistical
method may be needed.
The statistical method used must account for
data below the limit of detection with one or
more statistical procedures.
1.2.5.7
Groundwater
Protection Standards
Groundwater protection standards must be es-
tablished for each Appendix II constituent de-
tected in the groundwater. The groundwater
protection standard must be:
The MCL, if one has been established
under the Safe Drinking Water Act.
The background concentration for the
constituent if no MCL exists.
The background concentration if it is higher
than the MCL or health-based levels.
State-established alternative groundwa-
ter protection standard for constituents
with no established MCLs.
1-2.5.8
Appendix I
Appendix I of Part 258 identifies the 15 inorganic
and 47 organic constituents that must be included
1-23
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
in the groundwater detection monitoring pro-
gram. However, an alternative list of constituents
may be allowed in EPA-approved state programs.
1.2.5.9
Appendix II of Part 258 lists the hazardous inor-
Appendix II
ganic and organic constituents which must be in-
cluded in groundwater assessment monitoring
programs.
1.2.6
When an MSWLF unit ceases accepting wastes
Closure and
and is to be closed, the Subtitle D regulations
Post-Closure Care
prescribe detailed procedures the unit owner
(Subpart F)
must follow to accomplish closure.
1.2.6.1
A final cover system must be installed that is de-
Final Cover
signed to minimize infiltration and erosion. The fi-
nal cover system must consist of an erosion
layer and an infiltration layer designed according
to the standards described below.
The erosion layer must consist of a mini-
mum of 6 inches of earthen materials ca-
pable of sustaining native plant growth.
The infiltration layer must consist of a
minimum of 18 inches of earthen mate-
rial that has a permeability of less than,
or equal to, the permeability of any bot-
tom liner system or natural subsoils pre-
sent, or a permeability no greater than
1' 10-5 cm/sec, whichever is less.
Facilities with synthetic liner components
must have a synthetic component incor-
porated into the final cover design.
The erosion layer and infiltration layer
must be installed in direct contact with
each other.
1-24
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
The use of alternative final cover designs may
be allowed in EPA-approved state programs.
1.2.6.2 A written closure plan must be prepared that de-
Closure Plan scribes the steps necessary to close all MSWLF
units at any point during the active life of the facil-
ity. Closure must be performed in accordance
with the cover design requirements. The closure
plan must include:
A description of the final cover and the
methods and procedures used to install
the cover.
An estimate of the largest area of the
MSWLF unit ever requiring a cover at
any time during the facility's active life.
An estimate of the maximum inventory of
wastes ever onsite over the active life of
the landfill facility.
A schedule for completing all activities
necessary to satisfy the closure criteria.
Closure activities for each MSWLF unit must:
Begin within 30 days after the date on
which the final load of waste is received.
Be completed in accordance with the fa-
cility closure plan.
Be completed within 180 days after the
closure activities began.
However, if the MSWLF unit has remaining ca-
pacity and there is a reasonable likelihood that
additional wastes will be received, closure activi-
1-25
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
ties must begin no later than 1 year after the
most recent receipt of wastes, unless an addi-
tional extension is provided for in EPA-approved
state programs.
1.2.6.3 Post-closure care must be conducted for 30
Post-Closure Care years, unless it is increased or decreased by the
Requirements Director of an approved State. Post-closure care
consists, at a minimum, of the following:
Maintaining the integrity and effective-
ness of any final cover, including making
repairs to the cover as necessary to cor-
rect the effects of settlement, subsi-
dence, erosion or other events and
preventing run-on and runoff from erod-
ing or otherwise damaging the final cover.
Maintaining and operating the leachate
collection system.
Monitoring the groundwater and maintain-
ing the groundwater monitoring system.
Monitoring gas generation and maintain-
ing any gas management systems.
A written post-closure plan must be prepared
that includes:
The description and frequency of monitor-
ing and maintenance activities.
The name, address, and telephone num-
ber of the person to contact concerning
the facility during the post-closure period.
A description of the planned uses of the
property during the post-closure period.
1-26
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
1.2.7
Financial assurance must be established to
Financial Assurance
cover the cost of closure and post-closure care
Criteria (Subpart G)
of the MSWLF unit. The amount of the financial
assurance instrument must be based upon a de-
tailed written cost estimate, in current dollars.
The cost estimate must account for hiring a third
party to close the largest area of all MSWLF
units ever requiring a final cover at any time dur-
ing the active life of the facility when the extent
and manner of its operation would make closure
the most expensive.
The closure cost must be adjusted annually for
inflation during the active life of the MSWLF unit
and the financial assurance instrument must be
adjusted, as necessary.
1.3
The Subtitle D regulations, as revised, apply to
CHANGES IN
all new and existing MSWLFs and lateral expan-
APPLICABILITY AND
sions of MSWLFs. The small landfill exemption
EFFECTIVE DATES
provision included in the October 9, 1991, regula-
tions is no longer applicable. These facilities
must also comply with the regulations, although
on a modified schedule.
The regulations also apply to facilities that
closed before October 9, 1993, but do not com-
plete closure activities by October 9, 1994.
EPA extended some of the effective dates for
compliance with the Subtitle D regulations. The
schedule revisions (Figure 1-3):
Extend the effective date of the Subtitle
D regulations for 6 months for certain
small landfills accepting 100 tons per
day or less of solid waste.
1-27
-------
Summary of Changes to the Effective
Dates of the MSWLF Criteria
MSWLF Units
Accepting Greater
than 100 TPD
MSWLF Units Accepting 100 TPD
or Less; Are Not on the NPL; and
Are Located in a State that has
Submitted an Application for
Approval by 10/9/93, or on Indian
Lands or Indian Country
MSWLF Units that Meet
the Small Landfill
Exemption in 40 CFR
258.1(f)
MSWLF Units Receiving
Flood Related Waste
General Effective Date.
1 This is the effective
date for location,
operation, design, and
closure/post-closure.
October 9,1993
April 9, 1994
October 9, 1995
Up to October 9, 1994 as
determined by State
Date by which to install
final cover if receipt of
waste ceased by the
general effective date.
October 9, 1994
October 9, 1994
October 9, 1996
Within one year of date
determined by State; no
later than October 9, 1995
Effective date of
groundwater monitoring
and corrective action.
Prior to receipt of
waste for new
units;
October 9, 1994
through
October 9, 1996
for existing units
and lateral
expansions
Prior to receipt of waste for new
units; October 9, 1993 for new
units; October 9, 1994 through
October 9, 1996 for existing units
and lateral expansions
Prior to receipt of waste
for new units; October 9,
1995 for new units;
October 9, 1995 through
October 9, 1996 for
existing units and lateral
expansions
October 9, 1993 for new
units; October 9, 1994
through October 9, 1996
for existing units and
lateral expansions
Effective date of
financial assurance
requirements.
April 9, 1995
April 9, 1995
October 9, 1995
April 9, 1995
1 If a MSWLF unit receives waste after this date, the unit must comply with all of Part 258.
Figure 1-3
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Extend the effective date of the financial
assurance requirements for all landfills
for 1 year.
Provide an alternative schedule for small
landfills which were exempt under the Octo-
ber 9,1991, regulations (prior to revision).
Small landfills which were subject to the
small landfill exemption must now begin to
comply by October 9, 1995. This extension
provides these facilities with the same 2
years between the promulgation and effec-
tive dates to prepare for compliance that
was provided for all other facilities.
These extensions were intended to provide:
Additional time for local governments
and small landfills to develop the ability
and resources to comply.
Additional time for EPA to approve state
programs, thereby providing opportuni-
ties for use of the flexibility provisions.
Additional time for assessing and plan-
ning for new waste management facili-
ties and alternatives.
Provide equivalent planning time for
small landfills which were previously ex-
empt.
The full text of the extension provisions are in-
cluded in attachments E and F, reprinted from
the Federal Register announcements of October
1 and October 14, 1993.
1-29
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
1A
FLEXIBILITY IN
APPROVED STATES
The Subtitle D regulations establish minimum cri-
teria for self compliance by MSWLFs. The regula-
tions also contain numerous provisions which
enable state programs that have received EPA
approval to utilize site-specific information to
adapt some of the requirements for practical im-
plementation. The EPA regulations include spe-
cific conditions that the states must address in
using this flexibility. EPA-approved state pro-
grams may allow for the following, which also in-
clude the corresponding section numbers.
Location of new or lateral expansions of
MSWLFs in wetlands [258.12(a)],
Location of new or lateral expansions of
MSWLFs less than 200 feet from a Holo-
cene age fault [258.13(a)].
Location of new or lateral expansions of
MSWLFs in seismic impact zones
[258.14(a)].
Delayed closure for existing MSWLFs
that cannot make the location restriction
demonstrations [258.16(b)],
Alternative daily cover [258.21(b)],
Alternative schedules for methane gas re-
lease reporting and implementation of re-
medial action plans [258.23(c)(4)],
Alternative recordkeeping locations
[258.29(a)],
Alternative recordkeeping and notifica-
tion schedules (except for airport safety
1-30
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
and notifying landowners of Appendix I!
releases) [258.29(c)],
Alternative designs [258.40(a)(1)],
Alternative location of point of compli-
ance boundaries up to 150 meters from
the waste management unit boundary
[258.40(d)],
Suspension of groundwater monitoring if
no potential for groundwater impact ex-
ists [258.50(b)],
Alternative schedules for existing
MSWLFs and lateral expansions to com-
ply with the groundwater monitoring crite-
ria [258.50(d)].
Deletion of Appendix I parameters for de-
tection monitoring [258.54(a)(1)],
Alternative schedules for Appendix I de-
tection monitoring [258.54(b)]
Alternative schedules for placing notifica-
tion of statistical increases of Appendix I
constituents over background in the oper-
ating record [258.50(g) and 258.54(c)1)].
Multiunit groundwater monitoring sys-
tems [258.51(b)]
Alternative schedules for placing quali-
fied professional certifications relating to
monitoring systems in the operating re-
cord [258.51(d)(2)],
1-31
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
Alternative schedules for establishing as-
sessment monitoring or demonstrating
other sources or data errors [258.50(g),
258.54(c)(2) and 258.54(c)(3)].
Alternative schedules for conducting Ap-
pendix II sampling after initiating assess-
ment monitoring [258.50(g) and
258.55(b)].
Alternative subset of wells for conducting
Appendix II sampling for assessment
monitoring [258.55(b)],
Deletion of Appendix II parameters for as-
sessment monitoring [258.55(b)],
Alternative schedules for placing notifica-
tion of detected Appendix II constituents
in the operating record [258.50(g) and
258.55(d)(1)],
Alternative schedules for resampling Ap-
pendix I and Appendix II constituents
[258.55(c) and 258.55(d)(2)],
Alternative schedules for placing notifica-
tion of SSIs of Appendix II constituents
over groundwater protection standards in
the operating record [258.50(g) and
258.55(g)],
Alternative schedules for initiating as-
sessment of corrective measures or dem-
onstrating other sources or data errors
[258.50(g), 258.55(g)(1)(iv) and
258.56(a)],
1-32
-------
SECTION 1
General Overview of Municipal Solid Waste
Landfill Criteria
Alternative schedules for placing notifica-
tion of remedy selection in the operating
record [258.50(g) and 258.57(a)],
No cleanup action for particular constitu-
ents if determined unnecessary
[258.57(e)],
Alternative schedules for placing notifica-
tion of inability to implement a selected
remedy and selection of an alternative
remedy in the operating record
[258.50(g) and 258.58(c)(4)],
Alternative schedules for placing notifica-
tion of remedy completion in the operat-
ing record [258.50(g) and 258.58(f)],
Alternative schedules for beginning clo-
sure [258.60(f) and 258.60(g)],
Discontinuation of leachate management
[258.61(a)(2)],
Decreases or increases in the post-clo-
sure care period [258.61(b)(1) and
258.61(b)(2)].
Disturbance of the final cover
[258.61(c)(3)],
1-33
-------
SECTION 1 General Overview of Municipal Solid Waste
Landfill Criteria
References
1 U.S. Environmental Protection Agency, Design. Operation, and Closure of
Municipal Solid Waste Landfills.. EPA/600/K-92/002 (Washington, DC:
GPO, 1993).
2. Environmental Reporter. August 13. 1993.
3. Landfill Control Technologies. Technical Tips (1993V
4. National Archives and Records Administration, Federal Register. Vol. 56
(Washington, D.C.: GPO, October 9, 1991) p. 50978.
5. National Archives and Records Administration, Federal Register. Vol. 57
(Washington, D.C: GPO, June 26, 1992) p. 28626.
6. National Archives and Records Administration, Federal Register. Vol. 58
(Washington, D.C.: GPO, October 1, 1993) p. 51536.
7. National Archives and Records Administration, Federal Register. Vol. 58
(Washington, D.C.: GPO, October 14, 1993) p. 53136.
1-34
-------
-------
SECTION 2.0
Design Criteria
Page No.
2.1 INTRODUCTION 2-1
2.2 DESIGN CRITERIA 2-1
2.2.1 Design in Unapproved States 2-1
2.2.2 Design in Approved States 2-3
2.3 COMPOSITE LINER DESIGN 2-3
2.3.1 Components of a Composite Liner 2-3
2.3.2 Advantages of a Composite Liner 2-5
2.4 COMPACTED SOIL LINER 2-5
2.4.1 Construction Material 2-5
2.4.2 Construction Objectives 2-7
2.4.2.1 Soil Water Content 2-8
2.4.2.2 Type of Compaction 2-8
2.4.2.3 Compactive Energy 2-12
2.4.2.3.1 Weight of the Roller 2-14
2.4.2.3.2 Number of Passes 2-14
2.4.2.3.3 Lift Thickness 2-14
2.4.2.4 Size of Soil Clods 2-14
-------
2.5 FLEXIBLE MEMBRANE LINERS 2-20
2.5.1 Types and Thicknesses 2-20
2.5.2 Performance Criteria 2-20
2.5.2.1 Permeability 2-20
2.5.2.2 Chemical Compatibility 2-25
2.5.2.3 Mechanical Compatibility 2-27
2.5.2.4 Durability 2-29
2.5.3 Engineering Properties 2-30
2.5.3.1 Interface Frictional Properties 2-30
2.5.3.2 Allowable Tensile Strength and Strain 2-30
2.5.3.3 Puncture Resistance 2-33
2.5.4 Structural Details 2-33
2.5.4.1 Anchor Trenches 2-33
2.5.4.2 Access Ramps 2-34
2.5.4.3 Collection Standpipes 2-34
2.5.5 Mechanisms of Degradation 2-38
2.5.5.1 Ultraviolet Degradation 2-38
2.5.5.2 Chemical Degradation 2-38
2.5.5.3 Extraction Degradation 2-38
2.5.5.4 Oxidation Degradation 2-39
2.5.5.5 Biological Degradation 2-39
2.5.6 Stress-Induced Mechanisms 2-39
-------
2.5.6.1 Creep 2-40
2.5.6.2 Environmental Stress Cracking 2-40
2.5.6.3 Freeze-Thaw Cycle 2-41
2.5.6.4 Abrasion 2-41
2.6 LEACHATE COLLECTION AND REMOVAL SYSTEM (LCRS) 2-41
2.6.1 Definition and Purpose of LCRS 2-41
2.6.2 Typical LCRS Components 2-43
2.6.2.1 Low-Permeability Base 2-43
2.6.2.2 High-Permeability Drainage Layer 2-44
2.6.2.2.1 Soil Drainage Layers 2-44
2.6.2.2.2 Geosynthetic Drainage Nets 2-45
2.6.2.3 Leachate Collection Pipes 2-46
2.6.2.4 Protective Filter Layer 2-50
2.6.2.5 Leachate Collection Sumps 2-51
REFERENCES 2-52
List Of Figures Page No.
2-1 Composite Liner Components 2-2
2-2 Maximum Groundwater Concentrations at POC 2-4
2-3 Leachate Infiltration: Clay vs. Composite Liner 2-6
Hydraulic Conductivity and Dry Unit Weight as a Function of
-------
4
5 a-
6
7
8
9
10
11a
12
ฆ13
14
15
16
ฆ17
18
19
Molding Water Content 2-9
Compaction Equipment Guidance 2-10 thru 2-11
Effects of Compactive Effort on Maximum Density and Hydraulic
Conductivity 2-13
Effects of Soil Clod Size on Hydraulic Conductivity 2-15
Conductivity Between Lifts 2-17
Footed Rollers With Partly and Fully Penetrating Feet ... 2-18
Liner Construction on Side Slopes With
Horizontal and Parallel Lifts 2-19
Some Advantages and Disadvantages of the Basic Polymers of
Geomembranes 2-21 thru 2-24
Flexible Liner Evaluation Expert (FLEX) 2-28
Typical Range of Interface Friction Angles 2-31
Typical Mechanical Properties 2-32
Various Types of Geomembrane Anchor Trenches 2-35
Typical Access Ramp Geometry and Cross Section 2-36
Leachate Removal System With a High Volume Sump . . . 2-37
Sources of Leachate Generated by a Solid Waste
(Flowchart) 2-42
Definition of Terms for Mound Model Flow Rate
Calculations 2-48
-------
SECTION 2
Design Criteria
2A
INTRODUCTION
2^2
DESIGN CRITERIA
The design of the MSWLF is critical to ensure
that the wastes are secured in a stable environ-
ment that is protective of human health and the
natural environment. This section highlights the
design criteria of the Subtitle D regulations and
discusses the components of an effective landfill
design.
2.2.1
Design in Unapproved
States
In states whose RCRA Subtitle D programs have
not been approved by the EPA, MSWLFs must
be designed with a (Figure 2-1):
Composite liner consisting of an upper
FML (minimum 30-mil) and a lower com-
pacted soil layer at least 2 feet thick with
a hydraulic conductivity of no more than
1 x 10"7 cm/sec;
Leachate collection system; and
Point of Compliance (POC) at the unit
boundary.
A proposed design which differs from the Federal
composite design described above may be ap-
proved if it can be demonstrated that the design
protects the uppermost aquifer and the following
conditions are met:
The state determines that the design
meets the Federal performance stand-
ards;
The state petitions EPA to review its de-
termination; and
2-1
-------
Composite Liner and Leachate Collection
System Design
N3
i
K3
*
O
2
c0
c
cr
O;
0
a
3
I"
5
3"
Q
1
a
c
Q)
Protective
Soil or Cover
(optional)
Filter Medium
llll||l||IP||
' i:: '<: jij
O Drainage Material DrainPipes -~O
. .ฆ -vv^ull^ ~ j ,y,.,; low Permeability Soil ฃi-M$ ฃ&'"* -4"'. ฆ V-ป '
^ ^ "ฆ'r'-rn-r%V*ฃ- <ฆ:
Native Soil Foundation
\
FML
Lower Component
(compacted soil)
(Not to Scale)
(Source: EPA, 1988)
Figure 2-1
-------
SECTION 2
Design Criteria
EPA approves the state determination or
does not disapprove it in 30 days.
2.2.2 In States whose RCRA Subtitle D programs
Design in Approved have been approved by the EPA, MSWLFs must
States be designed to meet the following criteria:
Design approved by director of the ap-
proved state must ensure that the MCLs
of chemicals listed in Figure 2-2 will not
be exceeded in the uppermost aquifer at
the POC; and
The POC must not be more than 150 me-
ters from unit boundary and must be on
property of owner/operator.
When approving a design, the state will consider
the following factors:
Hydrogeologic characteristics of the facil-
ity and surrounding land;
Climatic factors of the area; and
Volume and physical and chemical char-
acteristics of the leachate.
2.3 Composite liners are specifically described in
COMPOSITE LINER Part 258 40
DESIGN
2.3.1 A composite liner consists of the following two
Components of a components:
Composite Liner
Compacted soil layer at least 2 feet thick
with a maximum hydraulic conductivity
(permeability) of 1 x 10~7 cm/sec; and
2-3
-------
Maximum Groundwater
Concentrations at POC
ho
4
a
o
2
Co
&
g
s1
I
8
i
3"
3'
tQ
0)
a
c
Q>
Chemical
MCL (mg/l)
Arsenic
0.05
Barium
1
Benzene
0.005
Cadmium
0.01
Carbon tetrachloride
0.005
Chromium (hexavalent)
0.05
2,4-Dichlorophenoxy acetic acid
0.1
1,4-Dichlorobenzene
0.075
1,2-Dichloroethane
0.005
1,1-Dichloroethylene
0.007
Endrin
0.0002
Fluoride
4
Lindane
0.004
Lead
0.05
Mercury
0.002
Methoxyclor
0.1
Nitrate
10
Selenium
0.01
Silver
0.05
Toxaphene
0.005
1,1,1 -Trichloromethane
0.2
Trichloroethylene
0.005
2,4,5-Trichlorophenoxy acetic acid
0.01
Vinyl chloride
0.002
Figure 2-2
-------
SECTION 2
Design Criteria
FML with minimum 30-mil thickness, or
60-mil thickness if composed of High
Density Polyethylene (HDPE).
2.3.2 a composite liner system should outperform
Advantages of a either FMLs or clay liners alone. With a clay
Composite Liner liner, the rate at which leachate will percolate
through the liner is dependent upon:
Hydraulic conductivity of the liner
Head of the leachate on top of the liner
Total area of the liner
With the addition of a FML in direct contact with
the upper surface of the clay, leakage through
the composite liner system is limited by
Number of breaks or openings in the
FML
Sizes of breaks or openings in the FML
2A
COMPACTED
SOIL LINER
2.4.1
Construction Material
In addition, any leachate moving down through a
hole or defect in the FML does not spread out be-
tween the FML and the clay liner (Figure 2-3).
Clay is the most important component of soil liners be-
cause the clay fraction of the soil ensures low hydrau-
lic conductivity. EPA requires that soil liners be built
so that the hydraulic conductivity is no greater than 1
x 10"7 cm/sec. To meet this requirement, the following
characteristics of soil materials should be met:
2-5
-------
Leachate Infiltration
Clay vs. Composite Liner
Clay Liner Composite Liner
nj
Leachate
-------
SECTION 2 Design Criteria
The soil should comprise at least 20 per-
cent fines (fine silt- and clay-size parti-
cles which will pass through a No. 200
sieve).
Plasticity index (PI) should be greater
than 10 percent. Soils with a high PI of
30 to 40 percent are sticky and difficult to
work in the field.
Coarse fragments should be screened to
no more than about 10 percent gravel-
size particles. Soils with a greater per-
centage of coarse fragments can contain
zones of gravel that have high hydraulic
conductivities. Gravel is material re-
tained on the No. 4 sieve.
The soil should contain no soil particles or
chunks of rock larger than 1 to 2 inches in
diameter. If a rock diameter becomes a sig-
nificant percentage of the thickness of a
layer of soil, rocks may form a permeable
"window" through a layer.
2.4.2 Although there are numerous factors that can
Construction contribute to soil liner failure, there are a few criti-
Objectives cal factors involved in the design and construc-
tion of a soil liner that have an effect on the liner
performance. The most important variables in
the construction of soil liners are the following
compaction variables:
Soil water content
Type of compaction
Compactive energy
2-7
-------
SECTION 2
Design Criteria
Size of soil clods
Bonding between lifts
Of these variables, soil water content is the most
critical parameter.
2.4.2.1 Figure 2-4 shows the influence of molding water
Soil Water Content content on hydraulic conductivity of the soil.
Molding water content is defined as the moisture
content of the soil at the time of molding or com-
paction.
The lower half of Figure 2-4 is a compaction
curve which shows the relationship between
dry unit weight, or dry density of the soil, and
water content of the soil. The optimum water
content is the molding water content at which
the maximum dry unit weight is achieved. It is
preferable to compact the soil at a water con-
tent greater than optimum to achieve minimal
hydraulic conductivity.
2.4.2.2 The method used in compacting the soil is an im-
Type of Compaction portant factor in achieving low hydraulic conduc-
tivity. Static compaction is a method by which
soil packed in a mold is squeezed with a piston
to compress the soil. In kneading compaction, a
probe or pie-shaped metal piece is pushed re-
peatedly into the soil. The kneading action re-
molds the soil and is generally more successful
in breaking down clods than is the static com-
pacting method.
The best type of field compaction equipment is a
sheepsfoot roller, with rods or feet protruding
from the drum and penetrating the soil, remold-
ing it and destroying the clods. Figure 2-5A & B
2-8
-------
Hydraulic Conductivity and Dry Unit
Weight as a Function of
Molding Water Content
-------
Compaction Equipment Guidance
Equipment
tyee
Sheepsfoot
rollers
Rubber tire
rollers
Applicability
For fine-grained soils or
dirty coarse-grained soils
with more than 20% passing
No. 200 mesh; not suitable
for clean coarse-grained
soils; particularly
appropriate for compaction
of linings where bonding of
lifts is important.
For clean, coarse-grained
soils with 4-8% passing No.
200 mesh.
For fine-grained soils or
well graded, dirty coarse-
grained soils with more than
8% passing No. 200 mesh.
Compacted
lift thickness,
in. (cm)
6
(15)
10
(25)
6-8
(15-20)
Passes or
coverages
4-6 passes
for fine-
grained soil;
6-8 passes
for coarse-
grained soil
3-5
4-6
Dimensions and weight of equipment
Soil type
Fine-grained
soil > PI 30
Fine-grained
soil PI < 30
Coarse-
grained soil
Foot contact
area,
in. (cm2)
5-12
(32-77)
7-14
(45-90)
10-14
(64-90)
Foot contact
pressures,
psi (MPa)
250-500
(17-34)
200-400
(1.4-2.8)
150-250
(1.0-1.7)
Efficient compaction of wet soils requires less
contact pressures than the same soils at lower
moisture contents.
Tire inflation pressures of 60 to 80 psi (0.41-
0.55 MPa) for clean granular material or base
course and subgrade compaction; wheel load
18,000-25,000 lb (80-110 kN); tire inflation
pressure in excess of 65 psi (0.45 MPaj for
fine-grained soils of high plasticity; for
uniform clean sands or silty fine sands, use
large size tires with pressure of 40 to 50 psi
(0.28-0.34) MPa.
Figure 2-5a
-------
Compaction Equipment Guidance (cont'd)
Equipment
tvpe
ADDlicabilitv
Compacted
lift thickness,
in. Ccinl
Passes or
coverages
Dimensions and weight of equipment
Smooth wheel
rollers
Appropriate for subgrade or
base course compaction of
well-graded sand-gravel
mixture.
8-12
(20-30)
4
Tandem type rollers for base course or
subgrade compaction, 10-15 ton weight (89-
133 kN), 300-500 lb per lineal in. (3.4-5.6
kN lineal cm) of width of real roller.
May be used for fine-
grained soils other than in
earth dams; not suitable for
clean well-graded sands or
silty uniform sands.
6-8
(15-20)
6
3-wheel roller for compaction of fine-grained
soil; weights from 5-6 tons (40-53 kN) for
materials of low plasticity to 10 tons (89 kN)
for materials with high plasticity.
Vibrating
baseplate
compactors
For coarse-grained soils
with less than about 12%
passing No. 200 mesh; best
suited for materials with 4-
8% passing No. 200 mesh,
placed thoroughly wet.
8-10
(20-25)
3
Single pads or plates should weigh no less
than 20 lb (0.89 kN); may be used in tandem
where working space is available; for clean
coarse-grained soil, vibration frequency
should be no less than 1,600 cycles per
minute.
Figure 2-5b
-------
SECTION 2
Design Criteria
lists different types of compaction equipment and
their uses.
2.4.2.3 Increasing the compactive energy results in
Compactive Energy
Increase in maximum density of the soil
Decrease in the optimum moisture con-
tent
Lower hydraulic conductivity
The lower half of Figure 2-6 shows that with an in-
crease in compactive energy, the maximum den-
sity of the soil increases, while the optimum
moisture content decreases. The top half of Figure
2-15 shows that an increase in compactive energy
also results in a lower hydraulic conductivity.
Typically, the design will specify the following
compaction criteria for the clay liner:
Dry unit weight to be 95 percent of the
maximum dry unit weight
Acceptable range of water content to
be 0 percent to 4 percent wet of opti-
mum moisture content
The compactive energy delivered to soil depends
on:
Weight of the roller
Number of passes of the roller over a
given area
Lift thickness
-------
Effects of Compactive Effort on Maximum
Density and Hydraulic Conductivity
10-5
108
E
tj
2-
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o
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nj
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5
$
ฃ 100
u
ฐ 92
Increasing
Effort
' Increasing
Effort
12 16 20
Molding Water Content (
24
(Source: EPA, 1989)
Figure 2-6
-------
SECTION 2
Design Criteria
2.4.2.3.1
Weight of the Roller
2.4.2.3.2
Number of Passes
2.4.2.3.3
Lift thickness
2.4.2.4
Size of Soil Clods
The heaviest rollers weigh between 50,000 and
70,000 pounds. Rollers that weigh up to 70,000
pounds may be desirable for compacting bottom
liners of landfills. However, heavy rollers cannot
be used if the soil is very wet or if the foundation
is wet and compressible. Rollers with static
weights ranging between 30,000 and 40,000
pounds are recommended for compacting low-
hydraulic conductivity layers in cover systems.
The compaction equipment must pass over the soil
liner a sufficient number of times to maximize the com-
paction. Typically, 5 to 20 passes are required over a
given lift of soil to ensure adequate compaction.
Soil liners should be constructed in a series of
compacted lifts. Determination of appropriate lift
thickness is dependent on the soil charac-
teristics, compaction equipment, firmness of the
foundation materials and the anticipated compac-
tive effort needed to achieve the required soil hy-
draulic conductivity. Soil liner lifts should be thin
enough to allow adequate compactive effort to
reach the lower portions of the lift. Thinner lifts
also provide greater assurance that sufficient
compaction can be achieved to provide good, ho-
mogeneous bonding between subsequent lifts.
Adequate compaction of lift thickness between 5
and 10 inches is possible if appropriate equip-
ment is used. The lift thickness of a clay liner is
typically 9 inches before compaction and 6
inches after compaction.
The term "clod" refers to chunks of cohesive soil.
For soils compacted at water content less than
optimum, the soil with smaller clods has a hy-
draulic conductivity much lower than soil with
larger clods (Figure 2-7). For soils compacted at
water content higher than optimum, the size of
2-14
-------
Effects of Soil Clod Size on
Hydraulic Conductivity
to
i
Ol
:o
O
Co
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O:
s1
งฆ
3
3"
3'
(Q
0)
3
C
0)
(Source: EPA, 1989)
Molding Water Content (%)
Figure 2-7
-------
SECTION 2
Design Criteria
2.4.2.5
Bonding Between Lifts
clods has a negligible effect. However, to reduce
the size of clods in dry materials, a road re-
claimer should be used. This device pulverizes
materials with teeth that rotate on a drum at a
high speed. The maximum size of clods may be
specified in the construction specifications.
The bonding between lifts is very important to
the integrity of the clay liner. If the lifts are not
properly bonded, hydraulic pathways can de-
velop (Figure 2-8). Since clay normally will de-
velop small vertical cracks, the lifts must be
bonded so that the cracks in each lift will not be
connected. The following guidelines will help pro-
mote good lift bonding:
The lift height should not be greater than
the length of the sheepsfoot on the com-
pactor (Figure 2-9);
The compactor should have a minimum
weight of 40,000 pounds and a minimum
sheepsfoot length of 8 inches;
The recommended minimum number of
passes the compactor should make is
five; and
The previous lift should be scarified prior
to placing the next lift to provide bonding.
The most difficult area to achieve uniform com-
paction is on side slopes, especially at the inter-
face between the side slope and the flat area.
Clay can be placed either parallel or horizontally
on the side slope (Figure 2-10). For steep slopes
(2.5V: 1H), the horizontal method should be
used. This is done by starting at the toe of the
slope and working up the slope.
2-16
-------
Conductivity Between Lifts
I
, 1989)
Figure 2-8
-------
Footed Rollers with Partly and Fully
Penetrating Feet
to
i
CO
*
O
CO
&
a-.
a?
<5*
งฆ
3
2'
5'
Fully Penetrating Feet on Roller
Compact Base of New, Loose of Soil
into Surface of Old. Previously
Compacted Lift
Partly Penetrating Feet on Roller Do
Not Extend to Base of New, Loose
Lift of Soil and Do Not Compact New
Lift into Surface of Old Lift
(Source: EPA, 1993)
Figure 2-9
-------
Liner Construction on Side Slopes with
Horizontal and Parallel Lifts
i
-------
SECTION 2 Design Criteria
2J>
FLEXIBLE
MEMBRANE LINERS
2.5.1 FMLs are made of one or more polymers along
Types with a variety of other ingredients such as carbon
and Thicknesses black, pigments, fillers, plasticizers, processing
aids, crosslinking chemicals, anti-degradants and
biocides. The polymeric materials most often used
as FMLs are:
High-density polyethylene
Polyvinyl chloride (PVC)
Chlorosulfonated polyethylene (CSPE)
FMLs are manufactured in thicknesses ranging
from 20 to 120 mil. The minimum thickness re-
quired by the Subtitle D Regulations for FMLs is
30 mil, with the exception of HDPE, which must
be at least 60 mil to allow for proper seam weld-
ing. Some advantages and disadvantages of the
basic polymeric FMLs are listed in Figure 2-11 A-
D.
2.5.2 There are four performance issues which deter-
Performance Criteria mine the effectiveness of the FML. Those are
Permeability
Chemical Compatibility
Mechanical Compatibility
Durability
2-20
-------
ro
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0
2
Co
&
Cfc
D
ฃ
s-
3
1
S*
3"
3"
(Q
Q>
3
C
0)
Some Advantages and Disadvantages of
the Basic Polymers of Geomembranes
ADVANTAGES
DISADVANTAGES
Polyvinyl Chloride (PVC) Thermoplastic
Low cost
Tough without reinforcement
Lightweight as single ply
Good seams - dielectric, solvent and heat
Large variation
Plasticized for flexibility
Poor weathering, backfill required
Plasticizer leaches over time
Poor cold crack
Poor high -- temperature performance
Blocking possible
Chlorinated Polyethylene (CPE) Thermoplastic
Good weathering
Easy seams -- dielectric and solvent
Cold crack resistance is good
Chemical resistance is good
Moderate cost
Plasticized with PVC
Seam reliability
Delamination is possible
Elasticized Polyolefin (3110), Thermoplastic EPDM -- Cured Rubbers
Good weathering
Lightweight as single ply
Cold crack resistance is good
Chemical resistance is good
Unsupported
Poor high temperature performance
Special seaming equipment required
Field repairs are difficult
Figure 2-11 a
-------
Some Advantages and Disadvantages of the
Basic Polymers of Geomembranes (cont'd)
ADVANTAGES
DISADVANTAGES
EPDM (4060) Thermoplastic Rubber
Good weathering Moderate cost
Cold crack resistance below 60 ฐF
Fair in high temperatures
Good seams -- heat-bonded
Blocking possible
No adhesives required
Fair chemical resistance
Butyl, Butyl/DPDM, EPDM
-- Cured Rubbers
Fair to good weathering
Moderate to high cost
Low permeability to gases
Poor field seams
High temperature resistance is good
Small panels
Nonblocking
Fair chemical resistance
Chloroprene (Neoprene) Cured Rubber
Good weathering
High cost
Good high temperature
Fair field seams -- solvent and tape
Good chemical resistance
Fair seams to foreign surfaces
-------
Some Advantages and Disadvantages of the
Basic Polymers of Geomembranes (cont'd)
K)
t
N)
CO
*
O
2
Co
D-
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8-
3
O'
0)
Q>
3'
IQ
I
3
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0)
ADVANTAGES
DISADVANTAGES
High-Density Polyethylene (HDPE) Semicrystalline Thermoplastic
Chemical resistance is good Low-friction surfaces
Good seams -- thermal and extrusion
Stress crack sensitive
Large variations in thickness
Seam workmanship critical
Low cost
High thermal expansion/contraction
Medium-, Low-, Very-Low-Density Polyethylene (MPDE, LDPE, VLDPE)
Semicrystalline Thermoplastic
Chemical resistance is good
Moderate thermal
expansion/contraction
Good seams -- thermal and extrusion
LDPE and VLDPE rarely used
Large variation in thickness
Low cost
No stress crack
MDPE often mistaken for HDPE
Figure 2-11 c
-------
Some Advantages and Disadvantages of the
Basic Polymers of Geomembranes (cont'd)
N)
i
N)
3)
1
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o,
if
I
8'
3"
I"
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ADVANTAGES DISADVANTAGES
Linear-Low-Density Polyethylene (LLDPE) Semicrystalline Thermoplastic
Chemical resistance is very good Moderate cost
Good seams -- thermal and extrusion LLDPE newly introduced
Large variation in thickness
High-friction surface
No stress crack
Figure 2-11 d
-------
SECTION 2
Design Criteria
2.5.2.1 The primary function of a liner system in a waste
Permeability management unit is to minimize and control the
flow of waste from the unit to the environment,
particularly to groundwater. A properly designed
FML has a low permeability to the waste con-
tained within the liner, allowing it to perform its
primary function. However, the permeability of
an FML made of a particular polymer may
change upon exposure to waste or leachate, de-
pending on the composition of the waste con-
tained by the FML. This property is the chemical
resistance, or compatibility, of a particular poly-
mer to specific chemicals.
Since plastics and rubbers exhibit various de-
grees of compatibility with different chemicals, a
number of materials are used to manufacture
FML sheeting. The material is selected based on
exposure during its intended use. An FML that is
compatible with a specific waste displays a low
permeability toward that waste and will minimize
its flow through the FML to the environment. Ad-
ditional factors affecting the rate of transmission
through the FML are thickness of the FML sheet-
ing and concentration of the chemical species.
2.5.2.2 Chemical compatibility of FMLs and waste liq-
Chemical Compatibility uids or leachates is a critical factor in the service
life of liner systems. Chemical compatibility re-
quires that the mechanical properties of the FML
remain essentially unchanged after the FML is
exposed to the waste. If the seams between the
sheets are made with materials other than the
sheet parent products, they also must be compat-
ible with the waste. Chemical incompatibility is
due primarily to:
Absorption of waste constituents by the
FML;
2-25
-------
SECTION 2
Design Criteria
Extraction of components of the FML
compound by wastes or leachates; or
Reactions between FML constituents
and wastes or leachates.
Incompatibility may result in a failure of the FML
material or of the liner seams and consequent leak-
age of waste or leachate to the groundwater. Due
to the serious consequences resulting from incom-
patibility, an evaluation is required prior to permit-
ting to determine the effects that waste will have on
the FML proposed for installation at a facility.
Evaluation of data obtained from compatibility
testing is best performed by specialists knowl-
edgeable in the following:
FMLs
FML Testing
EPA Method 9090
EPA Method 9090 is used to assess the compati-
bility of a candidate FML with the specific waste
liquid or leachate to be contained. Test proce-
dure includes:
Selection of representative samples of
the waste liquid or leachate and the FML
Preparation of the exposure cells for opera-
tion during the 120-day exposure period
Exposure of the FML samples to the waste
liquid or leachate in the simulated service
environment
2-26
-------
SECTION 2
Design Criteria
2.5.2.3
Mechanical Compatibility
Analysis of test data for trends during the
120-day exposure period
EPA has developed a computer advisory sys-
tem, the Flexible Liner Evaluation Expert (FLEX),
that serves as a tool to assist in interpretation of
data from Method 9090 tests (Figure 2-12). This
model, however, is not a substitute for review of
Method 9090 test results by a trained profes-
sional.
An FML must be mechanically compatible with
the designed use of the lined facility in order to
maintain its integrity during and after exposure to
short- and long-term mechanical stresses. Short-
term mechanical stresses can be caused by:
Equipment traffic during liner system instal-
lation:
Placement of materials on top of liner
Thermal expansion and shrinkage of the
FML during operation of the unit
Long-term mechanical stresses can be caused
by:
Placement of waste on top of the liner
system
Waste settlement
Differential settlement of the subgrade
Mechanical compatibility requires adequate friction
between the components of a liner system, particu-
larly the soil subgrade and the FML, to ensure that
slippage or sloughing does not occur on the slopes
2-27
-------
Flexible Liner Evaluation Expert (FLEX)
Computer program designed to assist reviewer in
analyzing EPA Method 9090 data
Not a substitute for review of Method 9090 test
results by a trained professional
Figure 2-12
-------
SECTION 2
Design Criteria
of the unit. Specifically, the foundation slopes
and the subgrade materials must be considered
in design equations in order to evaluate:
The ability of an FML to support its own
weight on the side slopes
The ability of the liner system to with-
stand downdragging during and after fill-
ing
The best anchorage configuration for the
the liner system
The stability of a soil cover on top of an
FML
Mechanical compatibility requirements may af-
fect the choice of FML material, including:
Polymer type
Fabric reinforcement
Thickness
2.5.2.4 An FML must exhibit durability; that is, it must be
Durability able to maintain its integrity and performance
characteristics over the operational life and the
post-closure care period of the unit. The service
life of an FML is dependent on the intrinsic dura-
bility of the FML material and on the conditions
to which it is exposed. Exposure conditions can
vary greatly within a given facility and an FML
must resist the combined effects of several
stresses, including:
2-29
-------
SECTION 2
Design Criteria
Chemical stresses
Physical stresses
Biological stresses
2.5.3
Engineering Properties
2.5.3.1
Interface Frictional
Properties
2.5.3.2
Allowable Tensile Strength
and Strain
Numerous engineering properties must be con-
sidered when selecting an FML, including
Interface frictional properties
Allowable tensile strength and strain
Puncture resistance
Since FML surfaces are smooth and relatively
slippery, the short- and long-term stability of the
materials placed above and below the liners, and
the entire liner system, has to be addressed. The
key design parameter is the interface friction an-
gle between the FML and the materials placed
above and below the liner. During the final de-
sign stage of landfill projects, it is recommended
that an interface friction test (American Society
for Testing and Materials [ASTM] D-5321) be per-
formed to determine the actual interface friction
angle between the proposed FML and the soil
materials in contact with the liner. Typical inter-
face friction angles between various FMLs and
soils are presented in Figure 2-13.
If the FML will be subjected to stretching or ten-
sile stress, the designer has to determine the al-
lowable strength and strain for the liners so that
the FML will not elongate, causing permanent
damage to the liner system. Allowable tensile
strengths will depend on the type of materials
used in the liner. Typical mechanical properties
are listed in Figure 2-14.
2-30
-------
Typical Range of Interface
Friction Angles*
INTERFACES FRICTION ANGLE
Geosynthetic/Soil
Stiff Geogrid/Sand 20ฐ to 34ฐ
HDPE FML (smooth)/Sand 18ฐ to 26ฐ
PVC FML/Sand 20ฐ to 28ฐ
Nonwoven Fabric/Clay 21 ฐ to 29ฐ
HDPE FML (smooth)/Clay 12ฐ to 19ฐ
PVC FM L/C I ay 13ฐ to 20ฐ
Nonwoven Fabric/Clay 14ฐ to 22
Geosynthetic/Geosynthetic
Nonwoven Fabric/HDPE FML (smooth) 9ฐ to 16
Nonwoven Fabric/PVC FML 12ฐ to 18
Nonwoven Fabric/Drainage Net 10ฐ to 16
HDPE FML (smooth)/Drainage Net 8ฐ to 15
*NOTE: The value of interface friction angles are product-dependent. Testing is recommended
based on product specifics and final intended use of the various geosynthetic products.
-------
Typical Mechanical Properties
HDPE
CPE
PVC
Density, gm/cm 3
> .935
1.3-1.37
1.24-1.3
Thermal coefficient of expansion
12.5 x 10 "5
4 x 10 "5
3 x 10 ~5
Tensile strength, psi
4800
1800
2200
Puncture, lb/mil
2.8
1.2
2.2
Figure 2-14
-------
SECTION 2
Design Criteria
2.5.3.3 Puncture resistance is especially important during
Puncture Resistance 'iner installation since construction equipment
spreads soil materials above the FML. The follow-
ing recommendations can help prevent puncturing
the FML:
Use low ground-pressure, track-type
equipment in the placement of materials
immediately above the liner;
Limit maximum particle size in contact with
the liner surface to three-eighths of an
inch; and:
Place minimum of 2 to 3 feet of soils on
top of the liner before any equipment is
operated above the liner.
2.5.4 Several avenues exist for potential structural fail-
Structural Details ure of FMLs, including:
Anchor trenches
Access ramps
Collection standpipes
2.5.4.1 An anchor trench along the perimeter of the land-
Anchor Trenches fill generally is used to secure the FML during
construction (to prevent sloughing or slipping
down the interior side slopes). However, if an-
chor trenches are not properly designed, they
can cause FMLs to fail in one of two ways: by rip-
ping out or by pulling out.
Run-out calculations are available to determine
the depth of burial at a trench necessary to hold
a specified length of FML, or combination of FML
and geofabric or geotextile (Section 2.6.2.4).
2-33
-------
SECTION 2
Design Criteria
Various anchorage configurations are shown in
Figure 2-15. In the "V" anchor configuration, re-
sistance can be increased by increasing the "V"
angle, however this design uses more space
than other configurations. The concrete trench
is not presently used.
2.5.4.2 Most facilities have access ramps (illustrated
Access Ramps jn Figure 2-16) which are used by trucks dur-
ing construction and by trucks bringing waste
into the facility. The integrity of the FML must be
maintained over the entire surface of the ramp.
Ramps can fail due to traffic-induced sliding, road-
way considerations and drainage; therefore, these
three factors must be considered during the design
and construction of access ramps.
The weight of the roadway, the weight of a vehi-
cle on the roadway and the vehicle braking force
all must be considered when evaluating the po-
tential for slippage due to traffic. The vehicle
braking force should be much greater than the
dead weight of the vehicles that will use it.
Wheelloads also have an impact on the liner sys-
tem and leachate collection system below the
roadway. Trucks with maximum axle loads of 90
pounds per square inch (psi) should be allowed
to use the ramps.
2.5.4.3 Collection standpipes are used to access the
Collection Standpipes leachate collection sumps (Figure 2-17). As
waste settles over time, downdrag forces can
have an impact on standpipes, including punc-
ture of the FML beneath the standpipe. To re-
duce the amount of downdrag force from the
waste, standpipes can be coated with viscous or
low-friction coating, or encapsulated with multiple
layers of HDPE.
2-34
-------
Various Types of Geomembrane
Anchors Trenches
(Dimensions are Typical and for Example Only)
Bolted Anchor System
(Source: EPA, 1993)
-------
Typical Access Ramp Geometry and
Cross Section
Roadway
Leachate
Collection
I Geomembrane
Leak
Detection
' Geomembrane
(b) Cross Section of Ramp Roadway
(Source: EPA, 1993)
Figure 2-17
-------
Leachate Removal System with
High-Volume Sump
ฆmmMh
Standpipe
Air Space
- PCP Pipe
M^Onftratinnal f.nvpr W^WA
LCR
2% Minimum
Sand
Otll IU s..K>v#rfcs*i!~uZsJSljSV!t.>--jr
lcr*
.wi i'iwj miwiiiปinir |- /V\L
s'i~
-------
SECTION 2
Design Criteria
2.5.5
Mechanisms of
Degradation
Several mechanisms exist which can contribute
to the degradation of FMLs, including:
2.5.5.1
Ultraviolet Degradation
Ultraviolet degradation
Chemical degradation
Extraction degradation
Oxidation degradation
Biological degradation
By virtue of its short wavelength components, sun-
light can enter into a polymer system and cause
chain scission and bond breaking. Two ap-
proaches are taken to minimize the effects of ultra-
violet degradation:
Adding carbon black to the formulation
Adding chemical stabilizers as scav-
enging agents
2.5.5.2
Chemical Degradation
Various chemicals can be aggressive to certain
types of FMLs. For this reason, EPA has developed
EPA Method 9090 for testing and assessing chemi-
cal resistance.
2.5.5.3
Extraction Degradation
If one or more of the components of an FML for-
mulation are extracted, the remaining material
may be compromised. The extraction of FML
components occurs when plasticizers leach out
of the FML, leaving a tacky substance on the sur-
face of the material. This phenomenon may de-
crease the elongation capability of the FML with
respect to tension, tear, and puncture modes of
2-38
-------
SECTION 2
Design Criteria
failure. The tests available to estimate extraction
are the:
ASTM D3083 for water extraction
ASTM D1203 for volatile loss
2.5.5.4 Oxidation of polymers caused by the gases or liq-
Oxidation Degradation uids interfacing with the FML is unavoidable. Oxy-
gen, over time, will enter into the polymer structure
and can react with various components in the par-
ticular formulation.
To minimize the oxidation reaction, the polymeric
formulation contains various antioxidants which
neutralize free radicals. The amount of oxidation
that can be neutralized, however, is limited, and
once this capacity is reached, the oxidation proc-
ess will proceed depending on site-specific and
FML-specific conditions.
2.5.5.5 Microorganisms may interact with the plasticizers
Biological Degradation and/or fillers used in certain FMLs. Two ASTM
tests have been developed to detect this type of
degradation:
G21 deals with resistance of plastics to
fungi; and:
G22 is the complementary test for bacte-
rial resistance.
Because animals could easily burrow through an
FML, its ability to withstand such forces must be
a factor in landfill design and material selection.
2.5.6 Several stress mechanisms which can affect
Stress-Induced polymers include:
Mechanisms
2-39
-------
SECTION 2 Design Criteria
Creep
Stress cracking
Freeze-thaw
Abrasion
2.5.6.1 Creep refers to the deformation of the FML over
Creep a prolonged period of time under constant stress.
It can occur at:
side slopes
anchor trenches
sumps
protrusions
settlement locations
folds and creases
If a liner is allowed to creep indefinitely, the FML
and the materials placed above it will be dam-
aged. According to the results of research on
creep, a minimum safety factor of 3 should be
maintained (i.e., ultimate breaking strength
should be at least 3 times the allowable tensile
strength).
2.5.6.2 Environmental stress cracking refers to the
Environmental Stress cracks developed on polyethylene (PE) liners (in-
Cracking eluding HDPE) when they are subjected to both
chemical (leachate) attacks and tensile stress.
Environmental stress cracking can be tested for
by submerging a strip of the PE liner in a repre-
sentative leachate solution at 122 ฐF and apply-
2-40
-------
SECTION 2
Design Criteria
2.5.6.3
Freeze-Thaw Cycle
2.5.6.4
Abrasion
2.6
LEACHATE
COLLECTION AND
REMOVAL SYSTEM
(LCRS)
ing a tensile load to the strip sample. Crack de-
velopment is observed and documented. Most
commercially available PE liners have performed
well in the test; however, field observations indi-
cate that exposed PE liners have a higher possi-
bility of developing environmental stress cracks.
Freeze-thaw cycling, or the process by which a
material undergoes alternating rapid extremes of
temperature, has proven to have an insignificant
effect on polymer strength or FML seam strength.
Polymeric materials experience some stress due to
wanning, thereby slightly decreasing their strength;
however, within the range of 0ฐ to 160 ฐF, there is
no loss of integrity. In addition, freeze-thaw is not
likely to be a problem if the material is buried suffi-
ciently deep.
Abrasion could potentially induce stress to the
FML. However, as with freeze-thaw, abrasion
should not be a problem provided that the FML
is buried under enough soil.
2.6.1
Definition and
Purpose of Lcrs
Leachate refers to liquid that has passed through
or emerged from solid waste and contains dis-
solved, suspended or immiscible materials re-
moved from the solid waste. At MSWLF units,
leachate is typically aqueous with limited, if any,
immiscible fluids or dissolved solvents.
The liquids that percolate through a waste come
from three sources (Figure 2-18):
2-41
-------
Sources of Leachate Generated by
Solid Waste
a
Overburden
Pressure
Outside Water
(Rainwater, Drainage)
Ni
I
N3
*
o
ง
Co
&
C*
C*
CD
0
5?
ง.
a
S
a1
3"
IQ
1
a
c
Ql
Liquid Portion of
the Waste
Solid Waste
Leachate Collection
and Removal System
Water Soluble
Portion of the Waste
Water from
Decomposition
of the Waste
IIIIIIIIIIIIIIIIIIIIIIIIIM
Solid Waste
Drainage
to Sump
Figure 2-19
-------
SECTION 2
Design Criteria
Water from outside the containment unit
(e.g. rainwater and surface drainage);
Liquids originally in the waste; and
Liquids generated by the decomposi-
tion of waste.
The primary function of the LCRS is to collect
and convey leachate out of the landfill unit and to
control the depth of the leachate above the liner.
The LCRS should be designed to meet the regu-
latory performance standard of maintaining less
than 30 cm (12 inches) depth of leachate, or
"head," above the liner.
2.6.2 Leachate is generally collected from the landfill
Typical LCRS through sand drainage layers, synthetic drainage
Components nets or granular drainage layers with perforated
plastic collection pipes and is then removed
through sumps or gravity drain carrier pipes. A typi-
cal LCRS should include the following components:
Low-permeability base (composite liner)
High-permeability drainage layer
Leachate collection pipes
Protective filter layer
Leachate collection sumps
2.6.2.1 The typical bottom liner slope:
Low-Permeability Base
Is a minimum of 2 percent after allowances
for settlement at all points in each system;
2-43
-------
SECTION 2 Design Criteria
Is necessary for effective gravity drain-
age through the entire operating and
post-closure period.
2.6.2.2 The high-permeability drainage layer is place di-
High-Permeability rectly over the liner or its protective bedding
Drainage Layer layer at a slope of at least 2 percent (the same
slope necessary for the composite liner). Often
the selection of a drainage material is based on
the onsite availability of natural granular materi-
als. An alternative to using natural granular mate-
rials is to use a synthetic drainage material such
as a geosynthetic drainage net (geonet).
Geonets are frequently substituted for granular
materials on steep sidewalls because maintain-
ing sand on the slope during construction and op-
eration of the landfill unit is more difficult.
2.6.2.2.1 If the drainage layer of the LCRS is constructed
Soil drainage layers of granular materials (e.g., sand or gravel), then
the layer should:
Be a minimum of 30 cm (12 inches)
thick; and :
Typically have a hydraulic conductivity of
no less than 1 x 10~2 cm/sec.
In addition, it should be demonstrated that this
granular drainage layer has sufficient bearing
strength to support expected loads. If the landfill
unit is designed on moderate-to-steep (15 per-
cent) grades, the landfill design should include
calculations demonstrating that the selected
granular drainage materials will be stable on the
most critical slopes (i.e., usually the steepest
slope) in the design. The calculations and as-
sumptions should be shown, especially the fric-
2-44
-------
SECTION 2
Design Criteria
tion angle between the geomembrane and soil,
and if possible, supported by laboratory and/or
field testing.
Coarse granular materials, unlike low-permeability
soils, can be placed dry and do not need to be heav-
ily compacted. Compacting granular soils tends to
grind the soil particles together, which increases the
fine material and reduces hydraulic conductivity. To
minimize settlement following material placement,
the granular material may be compacted with a vi-
bratory roller.
2.6.2.2.2 Geosynthetic drainage nets (geonets) may be
Geosynthetic substituted for the granular layers of the LCRS
drainage nets on the bottom and sidewalls of the landfill cells.
Among their advantages, geonets require less
space than perforated pipe or gravel, promote
rapid transmission of liquids, are lightweight and
easy to install and do not require seaming. They
do, however, require geotextile filters above
them and can experience problems with creep
and intrusion. Long-term operating and perform-
ance experience of geonets is limited because
the material and its application are relatively
new. Other disadvantages include limited hydrau-
lic capacity and less protection of liner.
If a geonet is used in place of a granular drain-
age layer, it must meet the same performance
standard (maintaining less than 30 cm of
leachate above the liner). The transmissivity of a
geonet can be reduced significantly by intrusion
of the soil or a geotextile. A protective geotextile
between the soil and geonet will help alleviate
this concern.
Geonets are often used on the sidewalls of land-
fills because of their ease of installation. When in-
2-45
-------
SECTION 2
Design Criteria
stalling a geonet on a side slope, the following is
recommended:
Secure in anchor trench.
Strongest longitudinal length to extend
down the slope.
Tied at edges, butted or overlapped (not
seamed).
Placed loosely, not in tension.
2.6.2.3 Perforated leachate collection pipes are placed
Leachate within the high-permeability drainage layer to col-
Collection Pipes lect leachate and carry it rapidly to a sump or col-
lection header pipe. Perforated drainage pipes
can provide good long-term performance, having
been shown to transmit fluids rapidly and to main-
tain good service lives. The depth of the drain-
age layer around the pipe should be deeper than
the diameter of the pipe. The pipes can be
placed in trenches to provide the extra depth. In
addition, the trench serves as a sump (low point)
for leachate collection. Pipes can be susceptible
to particulate and biological clogging similar to
the drainage layer material. Furthermore, all com-
ponents of the LCRS, including the collection
pipes, must have sufficient strength to support
the weight of:
overlying waste;
cover system;
post-closure loadings; and
stresses from operating equipment.
2-46
-------
SECTION 2
Design Criteria
The component that is most vulnerable to com-
pressive strength failure is the drainage layer pip-
ing. LCRS piping can fail by excessive
deflection, which may lead to buckling or col-
lapse. Pipe strength calculations should include
resistance to wall crushing, pipe deflection and
critical buckling pressure. Design equations and
information for most pipe types can be obtained
from the major pipe manufacturers.
The design of perforated collection pipes should
consider the following factors:
Required flow using known percolation
impingement rates and pipe spacing;
Pipe size using required flow and maxi-
mum slope; and:
Structural strength of the pipe.
The pipe spacing may be determined by the
Mound Model (Figure 2-19). Using a maximum al-
lowable head, hmax, of 30 cm (12 inches), the equa-
tion is usually solved for the pipe spacing, "L".
The amount of leachate can be calculated in a
variety of ways, including
Water Balance Method
Hydrologic Evaluation of Landfill Perform-
ance (HELP) Model
The HELP model is a computer-based mathe-
matical water-budget model that performs daily
sequential analyses to generate daily, monthly
and annual estimates of runoff, evapotranspira-
tion, lateral drainage, leakage through covers,
2-47
-------
Definition of Terms for Mound Model
Flow-Rate Calculations
00
7]
O
C/0
c
Cr
51
8-
3
a[
i
3"
3'
IQ
to
s
c
0)
Injlow
* i i I I I I \ I
where
c = q/k
k = permeability
q = inflow rate
(Source: EPA, 1989)
Figure 2-18
-------
SECTION 2
Design Criteria
leachate collection, leakage detection and leak-
age through clay liners and FMLs.
Clogging of the pipes and drainage layers of
the LCRS can occur through several mecha-
nisms, including
Physical (sedimentation)
Chemical
Biological
Physical clogging can be minimized by proper
sizing of the pipe perforations. The Army Corps
of Engineers has established design criteria us-
ing graded filters to prevent physical clogging of
leachate drainage layers and piping by soil sedi-
ment deposits.
Chemical clogging can occur when dissolved
species in the leachate precipitate in the piping.
Clogging can be minimized by periodically flush-
ing pipes or by providing a sufficiently steep
slope in the system to allow for high flow veloci-
ties for self-cleansing. These velocities are de-
pendent on the diameter of the precipitate
particles and on their specific gravity.
Biological clogging due to algae and bacterial
growth can be a serious problem in MSWLFs for
which there is no universally effective method of
prevention. Since organic materials will be pre-
sent in the landfill unit, there will be a potential
for biological clogging. The system design
should include features that allow for pipe sys-
tem cleanings. The components of the cleaning
system should include:
2-49
-------
SECTION 2
Design Criteria
A minimum of 6-inch diameter pipes to
facilitate cleaning;
Access located at major pipe intersections
or bends to allow for inspections and clean-
ing; and:
Valves, ports or other appurtenances to in-
troduce biocides and/or cleaning solutions.
2.6.2.4 The openings in drainage materials, whether
Protective Filter Layer holes in pipes, voids in gravel or apertures in
geonets, must be protected against clogging by
accumulation of fine (silt-sized) materials. An in-
termediate material that has smaller openings
than those of the drainage material can be used
as a filter between the waste and drainage layer.
Two materials used for the filter layer include
Sand or granular soil
Geotextiles
Sand may be used as filter material, but has the
disadvantage of taking up vertical space. A
granular filter layer is generally placed using the
same earth-moving equipment as the granular
drainage layer.
Geotextiles are often used as a filter layer. They
save vertical space, are easy to install and have
the added advantage of remaining stationary un-
der load. However, because geotextiles are sus-
ceptible to biological clogging, their use in areas
inundated by leachate (e.g., sumps, around
leachate collection pipes and trenches) should
be avoided. Another advantage of geotextiles is
their light weight and ease of placement. The
geotextiles are brought to the site, unrolled and
2-50
-------
SECTION 2
Design Criteria
held down with sandbags until they are covered
with a protective layer. They are usually over-
lapped, not seamed. However, on slopes or in
other configurations, they may be sewn.
2.6.2.5 Sumps, located in recesses at the low points
Leachate within the leachate collection drainage layer, pro-
Collection Sumps vide one method for leachate removal from the
MSWLF unit. In the past, low-volume sumps
have been constructed successfully from rein-
forced concrete pipe on a concrete footing and
supported above the geomembrane on a steel
plate to protect the geomembrane from punc-
ture. Recently, however, prefabricated polyethyl-
ene structures have become available. These
structures may be suitable for replacing the con-
crete components of the sump and have the ad-
vantage of being lighter in weight.
2-51
-------
SECTION 2
Design Criteria
References
1. National Archives and Records Administration, Federal Register. Vol. 58
(Washington, D.C.: GPO, October 1, 1993.
2. U.S. Environmental Protection Agency, Requirements for Hazardous
Waste Landfill Design. Construction, and Closure. EPA/625/4-89/022 (Cin-
cinnati, OH: GPO, 1989).
3. U.S. Environmental Protection Agency, Design and Construction of
RCRA/CERCLA Final Covers. EPA/625/4-91/025 (Cincinnati, OH: GPO,
1991).
4. U.S. Environmental Protection Agency, Guide to Technical Resources for
the Design of Land Disposal Facilities. EPA/625/6-88/018 (Cincinnati, OH:
GPO, 1988).
5. U.S. Environmental Protection Agency, Lining of Waste Containment and
Other Impoundment Facilities. EPA/600/2-88/052 (Cincinnati, OH: GPO,
1988).
6. U.S. Environmental Protection Agency, Seminars - Design. Operation and
Closure of Municipal Solid Waste Landfills. EPA/600/K-92/002 (April
1992).
7. Robert Koerner. Designing With Geosvnthetics (1990).
8. U.S. Environmental Protection Agency, Solid Waste Disposal Facility Cri-
teria. Technical Manual. EPA 530-R-93-017 (November 1993).
9. U.S. Environmental Protection Agency, Covers for Uncontrolled Hazard-
ous Waste Sites. EPA/540/2-85/002 (September 1985).
10. SCS Engineers, Virginia Landfill Training Manual, prepared under EPA
Contract No. 68-WO-0025, WA No. 253 for Science Applications Interna-
tional, SAIC Project No. 01-1026-03-2753-000 (May 1993).
2-52
-------
-------
SECTION 3.0
Construction Quality Assurance
Page No.
3.1 INTRODUCTION 3-1
3.2 ELEMENTS OF A CQA PLAN 3-1
3.2.1 Responsibility and Authority 3-1
3.2.2 CQA Personnel Requirements 3-3
3.2.3 Design Specifications 3-3
3.2.4 Inspection Activities 3-3
3.2.5 Sampling Requirements 3-6
3.2.5.1 100-Percent Inspection 3-6
3.2.5.2 Judgmental Sampling 3-8
3.2.5.3 Statistical Sampling 3-9
3.2.6 Acceptance/Rejection Criteria and Corrective Measures 3-9
3.2.7 Documentation 3-10
3.3 CQA FOR SOILS 3-11
3.3.1 Site Preparation 3-13
3.3.2 Subgrade Inspection for Bottom Liner 3-13
3.3.3 Soil Liner Materials Inspection 3-14
3.3.4 Placement of Soil Liner 3-16
-------
3.4 CQA FOR FLEXIBLE MEMBRANE LINERS 3-19
3.4.1 Storage At Site 3-19
3.4.2 Placement of the FML 3-19
3.4.3 FML Field Seams 3-23
3.4.3.1 Solvent Seams 3-25
3.4.3.2 Thermal Seams 3-28
3.4.3.2.1 Hot Air Seaming 3-28
3.4.3.2.2 Hot Wedge Seaming 3-28
3.4.3.2.3 Extrusion Welding 3-31
3.4.4 Seam Tests 3-31
3.4.4.1 Destructive Seam Tests 3-31
3.4.4.2 Nondestructive Seam Tests 3-34
3.4.4.2.1 Air Lance Method 3-38
3.4.4.2.2 Mechanical Point Stress or "Pick" Test 3-38
3.4.4.2.3 Electric Sparking 3-38
3.4.4.2.4 Pressurized Dual Seam 3-39
3.4.4.2.5 Vacuum Chambers 3-39
3.4.4.2.6 Ultrasonic Methods 3-40
3.5 CQA FOR LEACHATE COLLECTION AND RECOVERY SYSTEM 3-40
REFERENCES 3-42
-------
List of Figures Page No.
3-1 Recommendations For Construction of
Clay-Lined Landfills 3-7
3-2 Method for Testing Low-Permeability Soil Liners 3-12
3-3 Photographs of Temporary Storage of Geotextiles 3-20
3-4 Deployment of the Geomembrane 3-21
3-5 Photographs Showing the Unrolling and Unfolding
of Geomembranes 3-22
3-6 Wind Damage to Deployed Geomembrane 3-24
3-7 Field Seaming Techniques for Geomembranes 3-26
3-8 Photographs of Geomembrane Being Bonded 3-27
3-9 Cross Section of Automated Machine-Driven Hot Air
Seaming Device for Geomembranes 3-29
3-10 The Hot Wedge System 3-30
3-11 The Extrusion Welding System 3-32
3-12 Destructive Seam Tests 3-34
3-13a Overview of Nondestructive Seam Tests 3-35
3-13b Overview of Nondestructive Seam Tests 3-36
-------
SECTION 3
Construction Quality Assurance
3.1
INTRODUCTION
3i2
ELEMENTS OF A
CQA PLAN
Construction quality assurance (CQA) consists
of a planned series of observations and tests to
ensure that the final product meets project speci-
fications. CQA plans, specifications, observa-
tions and tests are used to provide quantitative
criteria with which to accept the final product. In
order to ensure that a landfill is constructed in ac-
cordance with the required design criteria, a sys-
tematic quality assurance program is required to
ensure that the proper materials, equipment and
procedures are utilized during the planning and
construction of the landfill and its components.
This section presents the elements of a CQA
plan and some of the CQA techniques utilized to
inspect the components of a MSWLF.
Several elements included in a CQA plan are:
Responsibility and authority
CQA personnel requirements
Design specifications
Inspection activities
Sampling requirements
Acceptance/rejection criteria and correc-
tive measures
Documentation
3.2.1 The permitting, designing, and construction of a
Responsibility and disposal facility involve a large number of organi-
Authority zations. Those organizations involved directly in
CQA include the following:
3-1
-------
SECTION 3
Construction Quality Assurance
The permitting agency,
The facility owner/operator,
The design engineer,
The CQA personnel,
The construction and installation contrac-
tors), and
The FML manufacturer (possibly).
These organizations are not necessarily mutually
exclusive. For example, the facility owner/opera-
tor may also be the construction contractor. The
CQA personnel may be employees of the facility
owner/operator, of the design engineer or of an
independent firm. The installer could also be the
FML manufacturer or fabricator. Regardless of
the relationships among the organizations, the ar-
eas of responsibility and the lines of authority for
each organization must be clearly delineated in a
CQA plan.
Periodic meetings and visits are necessary to en-
sure effective communication between all par-
ties. Project meetings will benefit all those
involved with the facility by ensuring familiarity
with:
Facility design
Construction procedures
Requirements of the CQA plan
Any design changes
3-2
-------
SECTION 3
Construction Quality Assurance
Examples of the types of meetings that may be
held include the following:
A preconstruction CQA meeting to resolve
any uncertainties about the design or the
CQA plan. This meeting should be held fol-
lowing the completion of the facility design
and site-specific CQA plan and the award
of the construction contract and should be
attended by the facility owner/operator, de-
sign engineer, CQA personnel, construc-
tion contractor and the installer, if one has
been selected.
Daily meetings to review progress.
Problem or work deficiency meetings to
be held as the need arises.
All CQA meetings should be documented.
3.2.2
CQA Personnel
Requirements
A CQA plan should identify the qualifications of
the CQA officer and the CQA inspection person-
nel in terms of the training and experience neces-
sary to fulfill their assigned responsibilities.
3.2.3
Design Specifications
Design specifications are a necessary part of the
CQA plan insofar as the purpose of a CQA plan
is to verify whether or not the various compo-
nents of the facility and the completed facility it-
self meet the design specifications.
3.2.4
Inspection Activities
The inspection activities to be performed during
the implementation of a CQA plan include obser-
vations and tests that ensure that the materials
of construction, the construction itself and the in-
stallation of the various components of the
MSWLF meet or exceed all design criteria, plans
and specifications. The wide range of materials
3-3
-------
SECTION 3
Construction Quality Assurance
and the number of activities involved in construc-
tion of a disposal facility is reflected in the num-
ber of different inspection activities that are
involved in implementing a CQA plan. The areas
for CQA inspection include
The earthworks (including the founda-
tion, the embankments and a low-perme-
ability soil liner in composite double-liner
systems);
The FML (from inspection of the raw ma-
terials up through inspection of the in-
stalled liner); and
The components of the leachate collec-
tion system.
It is important to select appropriate tests for in-
specting the quality of the construction materials
and the work and that the procedures proposed
to test the materials are well defined. For exam-
ple, some ASTM standards, such as ASTM
D638 which describes methods for testing the
tensile properties of plastics, include a range of
alternative testing procedures. Citation of the
number of a standard in a CQA plan may not be
enough to define the exact testing procedure to
be followed.
Ideally, CQA inspections and tests should meet
the following criteria:
A CQA inspection test should be a good
indicator of design quality.
A CQA inspection test or observation
should be accurate and precise. The test
results or observations should be docu-
3-4
-------
SECTION 3
Construction Quality Assurance
mentable (i.e., the results or observa-
tions should be numbers or well-defined
terms or phrases).
The results of a CQA inspection should
be available within a short period of time
so that acceptance decisions can be made
without causing interference with contractor
performance.
CQA inspection tests should be easy to
run using simple, rugged equipment.
Preferably, CQA inspection tests should
be nondestructive (i.e., should not dam-
age the integrity of any component of the
installed lining system).
The data generated during CQA inspection test-
ing are typically one of two types: attribute-type
data or measurement-type data. The type of
data that will be reported will depend on the test
method and the design specifications and on
how the acceptance/rejection criteria are stated.
Attribute-type data can be based on dichoto-
mous classifications (e.g., pass/fail, accept-
able/defective) or, in the case of FML destructive
seam testing, classifying the results as a film-
tearing bond break or a nonfilm-tearing bond
break. The criteria distinguishing classifications
should be clearly stated. In the case of FML
seam testing, a schematic of the different ways
in which tested specimens can break could be in-
cluded as part of the design specifications or the
CQA plan. Measurement-type data are test val-
ues which can be used to compute summary sta-
tistics such as means, variances and ranges. In
cases in which there are alternative means of cal-
3-5
-------
SECTION 3
Construction Quality Assurance
culating test values, the precise method for calcu-
lating should be stated.
3.2.5 For all types of QA testing, the sampling require-
Sampling Requirements ments need to be stated, including the method
for determining what constitutes a representative
sample.
Inspection and sampling requirements
should include:
Statements of the sampling strategy
Size or definition of the unit to be sam-
pled
Size of the sample itself
Sampling procedure
Number of specimens to be tested per
sample.
Figure 3-1 presents the recommended testing fre-
quencies of three components of a clay-lined
landfill.
There are three basic types of sampling strate-
gies:
100-percent inspection
Judgmental sampling
Statistical sampling
3.2.5.1 One hundred percent means that inspection is
100-Percent Inspection made continuously on every unit of a product be-
ing manufactured or fabricated. Since performing
3-6
-------
Recommendations For Construction of Clay-Lined
Landfills
Item
Testing
Frequency
1. Clay borrow source testing
Grain size
1,000 yd 3
Moisture content
1,000 yd 3
Atterberg limits (liquid limit and plasticity
index)
5,000 yd 3
Moisture-density curve
3
5,000 yd and all changes in material
Lab permeability (remolded samples)
10,000 yd3
2. Clay liner testing during
construction
Density (nuclear or sand cone)
3
5 tests/acre/lift (250 yd )
Moisture content
1 test/acre/lift (1,500 yd3 )
Undisturbed permeability
1 test/acre/lift (1,500 yd3)
Dry density (undisturbed sample)
1 test/acre/lift (1,500 yd3 )
Moisture content
(undisturbed sample)
1 test/acre/lift (1,500 yci3 )
Atterberg limits (liquid limit and plasticity
index)
1 test/acre/lift (1,500 yd3 )
Grain size (to the 2-micron particle size)
1 test/acre/lift (1,500 yd3 )
Moisture - density curve
(as per clay borrow requirements)
5,000 ycPand all changes in material
3. Granular drainage blanket
testing
Grain size (to the No. 200 sieve)
1,500 yd3
Permeability
3,000 yd3
Source: Wisconsin Department of Natural Resources Figure 3-1
-------
SECTION 3
Construction Quality Assurance
3.2.5.2
Judgmental Sampling
a 100-percent inspection of many materials and
construction processes is not practical, the qual-
ity of the material or process should be esti-
mated from testing a portion of the total
materials or constructed facility. Examples of this,
situation include estimations of the integrity of
FML seams by destructive testing and assess-
ments of the characteristics of the soil liner in an
FML/composite double liner.
Judgmental sampling refers to sampling proce-
dures in which decisions concerning sample
size, selection scheme and locations are based
on considerations not derived from probability
theory. The objective of such sampling may be to
test typical samples that represent the whole, to test
zones of suspect quality, or a combination of the
two. Thus, in sampling FML seams, samples could
be taken at a minimum frequency per unit of seam
length from locations assigned by the CQA inspector
before seaming is started and also from locations
that are of suspect quality.
The success of a judgmental sampling plan is de-
pendent on the knowledge, capability and experi-
ence of the design engineer, the CQA inspection
personnel, the CQA officer and the project man-
ager. Organizations that construct large numbers
of similar projects, such as the U.S. Army Corps
of Engineers or the U.S. Bureau of Reclamation,
often employ judgmental sampling plans using
sampling frequencies based on years of con-
struction experience. For example, more inten-
sive sampling may be required in areas where
design specifications are more difficult to meet
(e.g., field-seaming operations on the slopes of a
unit). The weakness of judgmental sampling is
that such methods are subject to biases and
sampling errors.
3-8
-------
SECTION 3
Construction Quality Assurance
3.2.5.3 Statistical sampling methods are based on princi-
Statistical Sampling P'es of probability theory and are used to esti-
mate selected characteristics (e.g., mean,
variance and percent defective) of the overall ma-
terials or construction process. These methods
are more rational, calculable and documentable
than judgmental methods and are recommended
whenever feasible and applicable. An important
element of all statistical methods is knowledge of
the inherent variability of the specified charac-
teristic to be measured. This variability can be a
function of material quality, construction opera-
tions, measurement techniques and instrumenta-
tion and the skill of the CQA personnel. The
weakness of specific statistical sampling meth-
ods depends on the applicability of the theoreti-
cal assumptions to the population to be sampled;
for example, whether the probability distribution
of sample test measurements is normal.
Knowledge about the applicability of statistical
sampling methods for the CQA of constructing a
waste containment unit is not well developed. In
practice, a balanced CQA program uses both
judgmental and statistical approaches to take ad-
vantage of the lack of bias in statistical sampling
methods and the experience and judgment of
qualified CQA personnel.
&1A
Acceptance/Rejection
Criteria and Corrective
Measures
The acceptance or rejection criteria for the in-
spection activities must be stated. The type of cri-
teria will depend on the type of data resulting
from the inspection testing. If the data being col-
lected are attribute-type data (e.g., film-tearing
bond break/nonfilm-tearing bond break for report-
ing the results of destructive testing of FML
seams), the maximum percentage of specimens
that are unacceptable per tested sample or the
maximum percentage of unacceptable samples
3-9
-------
SECTION 3
Construction Quality Assurance
per sample block should be stated. If the data be-
ing collected are measurement-type data, accep-
tance/rejection criteria are based on whether a
nominal level (e.g., mean median or variance)
meets the design specification value(s) for a spe-
cific measurement (e.g., FML seam strength).
The nature of the nominal level (i.e., whether it is
a median or a mean) should be stated in the
specifications.
The criteria for accepting or rejecting measure-
ments that appear to be atypical or in error must
be stated. These atypical or errant measure-
ments, called outliers, may be an extreme mani-
festation of the random variability inherent in
data resulting from testing a specific material or
process or they may be a result of a gross devia-
tion in the test procedure or an error in calculat-
ing or recording the numerical value.
When material or work is rejected because the
CQA inspection activities indicate that it does not
meet the design specifications, corrective meas-
ures must be implemented. The types of correc-
tive measures that should be taken and the
requirements for inspecting these measures
should be stated.
Thorough documentation is an important part of
the implementation and success of a CQA plan,
and documentation requirements for all CQA ac-
tivities should be described in detail in the plan.
These requirements should include items such as
Daily summary reports;
Inspection data sheets;
3-10 RCRA Subtitle D Technical Training Manual
12J
-------
SECTION 3
Construction Quality Assurance
3.3
CQA FOR SOILS
Problem identification and corrective
measure reports;
Block evaluation reports;
Acceptance reports; and
The final documentation, which is submit-
ted to the permitting agency.
Provisions for final storage of the CQA records
should also be included in the CQA plan.
Sampling and testing of the soil liner during all
phases of construction is necessary to ensure
quality control. Testing provides verification of
visual inspections. Field density and water con-
tent are two critical parameters which must be
tested frequently during construction activities.
Field and laboratory determinations should be
made for these parameters and for hydraulic con-
ductivity. Specific tests and methods are listed in
Figure 3-2.
A CQA plan must address the soils involved in
landfill construction and should address items
such as
Site preparation
Subgrade inspection for bottom liner
Soil layer materials
Placement
Compaction
These items can serve as a CQA checklist for
monitoring soil construction quality.
3-11
-------
Methods for Testing Low-Permeability
Soil Liners
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-------
SECTION 3
Construction Quality Assurance
3.3.1 The following items should be checked for when
Site Preparation observing the site preparation activities:
Is there any evidence of landsliding?
Look for large cracks in the ground or
other evidence of instability.
Are there proper controls on ground ele-
vations? Ask how elevations were deter-
mined and where the benchmark(s)
is/are located.
Have all grasses and tree roots been ex-
cavated in areas to receive engineered
barriers? Visually inspect.
3.3.2 The following items should be checked when in-
Subgrade Inspection for specting the subgrade for the bottom liner:
Bottom Liner
Is the subgrade free of organic matter?
Visually inspect.
Is the subgrade properly sloped as shown
on plans? Ask for details and be sure that
elevations are documented and confirmed
by survey.
Is the subgrade sufficiently strong to sup-
port equipment? Check by walking over
the area; feet should not sink into soil
more than 1 inch. Bounce up and down
on wet soil; ground should not visually
deform or quake.
Has the subgrade been tested for den-
sity and moisture at the required fre-
3-13
-------
SECTION 3
Construction Quality Assurance
3.3.3
Soil Liner
Materials Inspection
quency? Ask if tests were performed, if
tests are required.
Is the subgrade reasonably smooth?
Should be able to place a long stick or
rod onto surface at all locations and not
see separation large enough to accom-
modate a fist. If surface is uneven, it
should be "proof-rolled," (e.g., with
smooth steel-drum roller).
The following items should be checked when in-
specting the soil layer materials:
Material should be cohesive. Check by
rolling material into thread 1/8 inch in di-
ameter; if soil crumbles and cannot be
rolled into a thread, it may not have
enough fines; ask for quantitative assess-
ment.
Have Atterberg limits been measured?
Ask for this information and compare the
results with the minimum required values
for Liquid Limit and Plasticity Index. Ask
how the samples were selected and en-
sure (1) random sampling supplemented
by additional tests on suspect material,
(2) at least one sample taken per day of
operations and (3) sampling any time
there is an obvious change in material or
borrow source.
For soil/bentonite liners, has sufficient
bentonite been added, and has the blend-
ing been thorough? Ask how weights are
controlled and how bentonite is blended.
3-14
-------
SECTION 3
Construction Quality Assurance
Check for frequency and size of gravel-
size particles (greater than 4.76 millime-
ters or three-sixteenth inch) in diameter.
Do this visually. There is usually no prob-
lem if the gravel-size particles comprise
less than 10 percent of the material and
the largest particles are no larger than
about 2 inches. If larger particles are pre-
sent, they should be removed. If more
than 10 percent of the material is gravel,
ask for test data that demonstrates that
the gravel does not raise the permeabil-
ity above the maximum allowable value
Have grain-size analyses been per-
formed? Ask for this information and
compare the results with the minimum re-
quired value for percentage fines and the
maximum allowable value for percentage
of gravel. Ask how the samples were se-
lected and ensure (1) random sampling
supplemented by additional tests on sus-
pect material, (2) at least one sample
taken per day of operations and (3) sam-
pling any time there is an obvious
change in material or borrow source.
Is there evidence of deleterious mate-
rial? Look for roots, sticks, vegetation
and debris such as bricks.
Visually check water content; the mate-
rial should be placed in its final location
at a water content close to (within 2 to 3
percent of) the desired value. Small ad-
justments in water content can be made
just prior to compaction, but large adjust-
ments should be made in a separate con-
ditioning area. One learns mainly from
3-15
-------
SECTION 3
Construction Quality Assurance
3.3.4
Placement of Soil Liner
experience what is a satisfactory water
content by using the stabilization proce-
dures for determining plasticity index on
soil.
Check results of water content tests. Deter-
mine whether the water content of the ma-
terial in the borrow pit is close to (within 2
to 3 percent of) to the acceptable range of
water content. If the water content is not
close, the material should be taken to a
separate moisture adjustment area where
the soil is slowly wetted or dried, while be-
ing repeatedly mixed, over a period of at
least 48 hours to allow time for water to be
evenly distributed in the soil.
Check to make sure that the soil is wet-
ted or dried evenly. If the soil is dried, it
should be spread in a layer no thicker
than about 12 inches and mixed with till-
ing equipment. If the soil is wetted, water
should be evenly distributed over a layer
and the soil mixed with tilling equipment.
If the water content is changed by more
than 2 to 3 percent, the moisture adjust-
ment should be made in a separate con-
ditioning area.
The following items should be checked when ob-
serving the placement of the soil liner:
Check subgrade for roughness. Except
for the first lift, a new lift should never be
placed on a smooth surface. Visually ob-
serve the surface to receive the new lift
to be sure it has been roughened either
by rolling with an extended foot roller or
by using scarification equipment. Scarifi-
3-16
-------
SECTION 3
Construction Quality Assurance
3.3.5
Compaction of Soil Liner
cation, if performed, should be to a depth
of approximately 1 inch.
Check subgrade for desiccation damage.
Visually inspect subgrade; look for evi-
dence that surface has dried out. If pre-
viously compacted lift has desiccation
cracks wider than one-eighth inch or is
suspected of having desiccated (e.g., be-
cause of change in color), require addi-
tional water content tests. Compare
water contents with values measured im-
mediately after compaction. If necessary,
excavate damaged lift(s) and rebuild.
Check loose lift thickness. Loose lifts are
normally less than 9 inches thick. Inspect
visually from the edge of a lift or from
grade stakes, or dig down through a
loose lift and measure its thickness.
Check for repair of any grade stake
holes and be sure that grade stakes are
recovered and not buried in the liner.
Ask how the grade stake holes are re-
paired and request a demonstration. Ask
what methods are used (e.g., inventory
procedures) to ensure that all grade
stakes are recovered.
The following items should be checked when ob-
serving the compaction of the soil liner:
Check that the compactor meets require-
ments. Check weight, type of drum
(footed or smooth), length of feet on
drum and type of energy (static or vibra-
tory).
3-17
-------
SECTION 3
Construction Quality Assurance
Check that the number of passes over an area
is adequate. Ask if there is a minimum, and if
so, what procedures are followed to spot check
for compliance. Count the passes over a given
area to confirm for at least one location.
For liners on slopes, check to be sure compac-
tor is not shearing the liner. On sloping landfill
covers compacted with heavy equipment, the
compactor tends to slip down the slope and
may shear the low-permeability soil layer if the
slope is too steep and/or the compactor too
heavy. Look for scarps or shear surfaces.
Check the water content and dry density of the
compacted soil. Ask for test results and deter-
mine (1) whether sampling was random, with
additional tests as required in suspect areas, or
to be certain that at least one test was per-
formed each day that soil was compacted; (2)
how the tests were performed; (3) whether the
water content tests are periodically checked
with overnight oven drying, and if so, how the
test results compare; (4) whether nuclear den-
sity test results (if this type of test is used) are
periodically checked with the sand cone; (5)
how holes made for the water content and den-
sity tests are repaired (ask for a demonstration);
and (6) how the water content and density re-
sults compare with the specifications.
Determine the protocol to be followed if a water
content or dry density test fails. Ask for an ex-
planation. Determine if a mechanism exists to
overrule an erroneous water content or density
test. Look for at least three passing tests required
to overrule a failing test that requires repair.
3-18
-------
SECTION 3
Construction Quality Assurance
CQA FOR FLEXIBLE
MEMBRANE LINERS
2A1
Storage At Site
3.4.2
Placement of the FML
The following issues should be considered when
conducting CQA on FMLs:
Storage at the site
Deployment of the FML
Field seaming and seam testing of FMLs
Unless the FML is used directly as it comes off
the shipping trailer, a safe storage area should
be provided (Figure 3-3). The rolls of FML should
be elevated off the ground or at least placed on
a dry soil area that does not contain vegetation,
stumps or other sharp objects. Covering is usu-
ally not necessary providing the FMLs are in-
stalled within a short period of time. Palletized
FMLs should also be stored onsite on dry, level
ground with similar considerations. When the
FMLs are to be stored on the site for months or
longer, they should be covered and/or have an
enclosure around them for protection.
Placement of the FML panels or rolls should be
described in the FML layout plan (Figure 3-4).
Rolls of sheeting, such as HDPE, can generally
be deployed by placing a shaft through the core
of the roll, which is supported and deployed us-
ing a front-end loader or a winch. Panels com-
posed of extremely flexible liner material, such
as PVC, are usually folded on pallets, requiring
workers to manually unfold and place the FML
(Figure 3-5).
Usually the rolls or panels are ordered in a par-
ticular direction. After a roll, or panel, is initially
positioned or "spotted," it usually must be shifted
slightly for exact positioning. By lifting the liner
3-19
-------
Photographs of Temporary Storage of Geotextiles
-------
Deployment of the Geomembrane
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Panel-seam identification scheme
o Panel Number
Seam Number
Figure 3-4
-------
Photographs Showing the Unrolling and
Unfolding of Geomembranes
Unfolding Geomembranes
(Source: EPA , 1993) Figure 3-5
-------
SECTION 3
Construction Quality Assurance
up and allowing air to get beneath some of it, the
liner can sometimes be "floated" into position If
this is not possible (e.g., with thick FML sheets),
the liner has to be shifted by dragging it along
the subgrade (or on the geosynthetic material be-
neath it).
The entire roll or panel must then be inspected
for blemishes, scratches and imperfections. Fi-
nally, the roll or panel is weighted down with
sandbags to prevent movement by wind or any
other disturbance (Figure 3-6). Proper stormwa-
ter control measurements should be employed
during construction to prevent erosion of the soil
liner underneath the FML and the washing away
of the FML.
Placement of the FML goes hand-in-hand with
the seaming process; no more than the amount
of sheeting that can be seamed during a shift of
work day should be deployed at any one time.
3-4.3 The construction of a continuous watertight FML
FML Field Seams jS critical to the containment of municipal waste
and is heavily dependent on the construction of
the seams bonding the sheeting together. The
seams are the most likely source of failure in an
FML. The quality of seams made in the field is
difficult to maintain since the installer must deal
with a variety of conditions, including:
Changing weather conditions (tempera-
ture, wind and precipitation)
Unclean site conditions
Working on slopes
3-23
-------
Wind Damage to Deployed
-------
SECTION 3
Construction Quality Assurance
In general, for a seaming system to be accept-
able, the bonding:
Between the sheets of FMLs must be
continuous for the length of the seam;
Between the sheets must approximate
the strength of the sheeting and must
maintain its strength throughout the serv-
ice life of the sheeting; and
Must be capable of being formed in the
field.
Different types of FMLs require different types of
field seams and seaming methods (Figure 3-7).
Field seaming methods of the most popular
FMLs such as HDPE, PVC and CSPE include:
Solvent seams
Thermal seams
3.4.3.1
Solvent Seams
Both PVC and CSPE use solvent seams as the
bonding medium between sheets. A liquid sol-
vent is placed (using a squeeze bottle) between
the two FML sheets to be joined, followed by
pressure to make complete contact (Figure 3-8).
In the seaming process, a portion of the two adja-
cent geomembranes is actually dissolved. There-
fore, an excessive amount of solvent will weaken
the adjoining FMLs, and too little solvent will re-
sult in a weak seam. As a result, care must be
taken in the amount of solvent applied, the
amount of elapsed time and time of contact and
the amount of pressure applied.
3-25
-------
Field Seaming Techniques for
Geomembranes
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Photographs of Geomembrane Being
Bonded
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Alignment of test strip and cleaning
of area to be bonded
1
Applying fusion chemical
to area of lower geomembrane
to be bonded
(Source: EPA, 1991)
Figure 3-8
-------
SECTION 3
Construction Quality Assurance
3.4.3.2 There are a number of thermal methods that can
Thermal Seams be used on thermoplastic FML materials. In all
methods, the opposing FML surfaces are truly
melted into a liquid state. Temperature, time and
pressure all play important roles; too much melt-
ing weakens the FML, and too little melting re-
sults in a weak seam. The types of thermal
seams are:
Hot air seaming
Hot wedge seaming
Extrusion welding
3.4.3.2.1 Hot air seaming uses a machine consisting of a re-
Hot Air Seaming sistance heater, a blower and temperature controls
to blow air between two sheets to actually melt the
opposing surfaces (Figure 3-9). Usually, tempera-
tures greater than 260ฐC (500ฐF) are required. Im-
mediately following the melting of the surfaces,
pressure is applied by rollers. For some devices,
pressure application is automated by counter-rotat-
ing knurled rollers.
3.4.3.2.2 In the hot wedge or hot knife method (Figure 3-
Hot wedge seaming 10), an electrically heated resistance element in
the shape of a wedge is passed between the two
sheets to be sealed. As it melts the opposing sur-
faces, roller pressure is applied. Most of these
seaming units are automated in terms of tem-
perature, speed of travel and amount of pressure
applied. An interesting variation of the technique
is the dual-hot-wedge method, which forms two
parallel seams with an unbonded space between
them. This space is subsequently pressurized
with air and any lowering of pressure signifies a
leak in the seam. Lengths of hundreds of feet
can be field-tested in this one step. The hot
3-28
-------
Cross Section of Automated Machine-Driven
Hot-Air Seaming Device for Geomembranes
Direction of Travel
Figure 3-9
-------
The Hot Wedge
System
(Source: EPA, 1991)
Figure 3-10
-------
SECTION 3 Construction Quality Assurance
wedge or hot knife method will be described further
in the section on nondestructive seam testing.
3.4.3.2.3
Extrusion welding
Extrusion (or fusion) welding (Figure 3-11) is used
exclusively on polyethylene FMLs. It is directly par-
allel to metallurgical welding in that a ribbon of mol-
ten polymer is extruded between or against the two
lightly buffed surfaces to be joined. The extruded
ribbon causes some of the sheet material to be
liquified and the entire mass then fuses together.
One patented system has a mixer in the molten
zone that aids in homogenizing the extruded and
the molten surfaces. The technique is called flat
welding when the extruded ribbon is placed between
the two sheets to be joined and fillet welding when
the extruded ribbon is placed over the leading edge
of the seam to be bonded.
ZAA
Seam Test
3.4.4.1
Destructive Seam Tests
After a field-seaming crew has seamed a given
amount of material, it is important to evaluate per-
formance of the seams. This may be done by cut-
ting out a sample for laboratory testing or testing
the seams directly at the field site. Given the size of
FML sheet layout, selection of the number and lo-
cations of the seam test sites is an important con-
sideration. Because each seam sample becomes a
hole that must be appropriately patched and then
retested, the number of field-seam samples is com-
monly kept to a minimum. Such sampling will re-
veal the soundness of the method of seaming, but
not whether all of the seams are sound. Samples
will ordinarily be taken at the start of the seaming
operations in the morning and after the midday
break. Thereafter, sampling can be done on a ran-
dom or a periodic basis. One manufacturer recom-
mends a frequency of six samples per km (6/3,300
3-31
-------
The Extrusion Welding System
HDPE Extrudate
Contact Tube & Die with
Pressure Hot Air Jets
Welding Direction
Photograph and schematic
diagram of extrusion flat seaming
of geomembrane sheets.
(Source: EPA, 1991)
Figure 3-11
-------
SECTION 3
Construction Quality Assurance
feet) of seam on a random basis, or one sample per
150 m (1/500 feet) of seam on a uniform basis.
There is considerable discussion on what consti-
tutes an acceptable seam. There is nearly univer-
sal agreement that the seam test specimen must
not fail within the seamed region itself; that is, a
failure must be a sheet failure on either side of
the seamed region. This is called a "film-tear
bond" failure. Engineers are not in agreement,
however, as to the magnitude of the force re-
quired for failure. For seams tested in a shear
mode, failure forces of 80 to 100 percent of the
unseamed sheet strength are usually specified.
For seams tested in a peel mode, failure forces
of 50 to 80 percent of the unseamed sheet
strength are often specified. These percentages
underscore the severity of peel tests as com-
pared to shear tests. For assessing seam qual-
ity, the peel test is preferable (Figure 3-12).
3.4.4.2 a number of nondestructive seam tests exist, in-
Nondestructive eluding (Figure 3-13a, b)
Seam Tests
Air lance method
Mechanical point stress or "pick" test
Electric sparking
Pressurized dual seam method
Vacuum chambers
Ultrasonic methods
3-33
-------
Destructive Seam Tests
1
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Overview of Nondestructive Seam Tests
Primary Users
Nondestructive Test Method
Contractor
Design Engineer
Inspector
Third-Party
Inspector
Air Lance
Yes
-
-
Pick Test
Yes
-
-
Electric Wire
Yes
Yes
-
Dual Seam (positive pressure)
Yes
Yes
-
Vacuum Chamber
(negative pressure)
Yes
Yes
-
Ultrasonic Pulse Echo
-
Yes
Yes
Ultrasonic Impedance
-
Yes
Yes
Ultrasonic Shadow
-
Yes
Yes
Electric Field
Yes
Yes
Yes
Acoustic Sensing
Yes
Yes
Yes
(Source: EPA, 1989)
Figure 3-13 a
-------
Overview of Nondestructive Seam Tests
(cont'd)
General Comments
Non-Destructive
Test Method
Cost of
Equipment
Speed of
Tests
Cost of
Tests
Type of
Result
Recording
Method
Operator
Dependency
Air Lance
$200
Fast
Nil
Yes-No
Manual
Very High
Pick Test
Nil
Fast
Nil
Yes-No
Manual
Very High
Electric Wire
$500
Fast
Nil
Yes-No
Manual
High
Dual Seam
(positive pressure)
$200
Fast
Mod.
Yes-No
Manual
Low
Vacuum Chamber
(negative pressure)
$1,000
Slow
Very High
Yes-No
Manual
High
Ultrasonic Pulse
Echo
$5,000
Moderate
High
Yes-No
Automatic
Moderate
Ultrasonic
Impedance
$7,000
Moderate
High
Qualitative
Automatic
Unknown
Ultrasonic Shadow
$5,000
Moderate
High
Qualitative
Automatic
Moderate
Electric Field
$20,000
Slow
High
Yes-No
Manual and
Automatic
Low
Acoustic Sensing
$1,000
Fast
Nil
Yes-No
Manual
Moderate
(Source: EPA, 1989) Figure 3-13 b
-------
SECTION 3
Construction Quality Assurance
3.4.4.2.1
Air lance method
The air lance method projects a jet of air at ap-
proximately 350 kPa (50 lb/in2. ) pressure
through an orifice of 50-mm (3/16-in.) diameter.
The jet is directed beneath the upper edge of the
overlapped seam to detect unbonded areas.
When such an area is located, the air passes
through, causing an inflation and fluttering in the
localized area. This method only works on rela-
tively thin (less than 45 mils [1.1 mm]) FMLs and
only if the defect is open at the front edge of the
seam, where the air jet is directed. It is strictly a
contractor/installer's tool to be used in a con-
struction quality control manner.
3.4.4.2.2
Mechanical point stress or
"pick" test
In the mechanical point stress or "pick" test, the
tester places a dull tool (such as a blunt screw-
driver) under the top edge of a seam. With care, an
individual can detect an unbonded area, since an
unbonded area is easier to lift than a properly
bonded area. This rapid test depends completely
on the care and sensitivity of the person performing
it. Only relatively thick, stiff FMLs are checked by
this method. Detectability is similar to that using the
air lance, but both methods are operator dependent.
This test should be performed only by the installation
contractor and/or FML manufacturer.
3.4.4.2.3
Electric sparking
Electric sparking is an old technique used to de-
tect pinholes in thermoplastic liners. In this
method, a high-voltage (15 to 30kV) current de-
tects leakage to ground (through an unbonded
area) by producing sparking. The method is not
very sensitive to overlapped seams of the type
generally used in FMLs and is used only rarely
for this purpose. Today, the technique has been
revived in a somewhat varied form. In the elec-
tric wire method, a copper or stainless steel wire
is placed between the overlapped FML region
and is actually embedded into the completed
3-37
-------
SECTION 3
Construction Quality Assurance
seam. After seaming, a charged probe of about
20,000 volts is connected to one end of the wire
and slowly moved over the length of the seam. A
seam defect between the probe and the embed-
ded wire produces an audible alarm from the unit
3.4.4.2.4 The pressurized dual seam method was men-
Pressurized dual seam tioned earlier in connection with the dual-hot-
wedge thermal seaming method. The air channel
that results between the double seam is inflated
using a hypodermic needle and pressurized to
200 kPa (30 lb/in2). If no drop in pressure for a
given gauged length occurs, the seam is accept-
able; if a drop in pressure occurs, a number of
actions can be taken:
The distance can be systemically halved
until the leak is located;
The section can be tested by some other
leak detection method; or
A cap strip can be seamed over the entire
edge.
3.4.4.2.5 Vacuum chambers (boxes) are the most common
Vacuum chambers form of nondestructive test currently used by design
engineers and CQA inspectors. In the vacuum
chamber method, a 1-meter (3-foot)-long box with a
transparent top is placed over the seam, which has
been covered with a soapy solution, and a vacuum
of approximately 17 kPa (2.5 lb/in2) is applied. If
there is a leak in the seam, the vacuum is reduced
due to air entering the box from beneath the liner
through the leak and the soapy solution will bubble,
showing the location of the leak. The test is slow to
perform, and it is often difficult to achieve a vacuum-
tight joint at the bottom of the box where the box
passes over the seam edges. Due to the upward de-
3-38
-------
SECTION 3
Construction Quality Assurance
formations of the liner into the vacuum box, only
FMLs with a thickness greater than 30 mils (0.75
mm) should be tested in this manner. It would be
difficult to test 100 percent of the field seams by
this method because of the large number of field
seams and the amount of time required. This
test method cannot inspect around sumps, an-
chor trenches or patches with any degree of as-
surance. The method is also essentially
impossible to use on side slopes, since the down-
ward pressure required to make a good seal can-
not be obtained as it is usually done by standing
on top of the box.
3.4.4.2.6 Ultrasonic methods may be used in a variety of
Ultrasonic methods seam tests. The ultrasonic equipment measures
the energy transfer across a seam using two roll-
ers: one that transmits a high frequency signal,
and one that receives it. An anomaly in the sig-
nal, which is shown on an oscilloscope, indicates
some change in properties, typically a void
(caused by the presence of water). Ultrasonic
equipment, however, will not detect a tacked,
low-strength seam or dirt contamination, and the
tests are highly operator-dependent. Some ultra-
sonic methods include:
Ultrasonic pulse
Ultrasonic impedance
Ultrasonic shadow
3.5
CQA FOR LEACHATE
COLLECTION AND
RECOVERY SYSTEM
The purpose of leachate collection system CQA is to
document that the system construction is in accord-
ance with the design specifications. Prior to construc-
tion, all materials should be inspected to confirm that
they meet the construction plans and specifications.
These include:
3-39
-------
SECTION 3
Construction Quality Assurance
Geonets;
Geotextiles;
Pipe size, materials, and perforations;
Granular material gradation and prefabri-
cated structures (sumps, manholes, etc.);
Mechanical, electrical and monitoring
equipment; and
Concrete forms and reinforcement.
The construction of the LCRS foundation
(geomembrane or low-permeability soil liner) is
critical. The foundation should be inspected and
surveyed upon its completion to ensure that it
has proper grading and is free of debris and liq-
uids.
During construction, the following activities, as
appropriate, should be observed and docu-
mented:
Pipe bedding placement, including qual-
ity, thickness and area coverage;
Granular filter layer placement, including
material quality and thickness;
Pipe installation, including location, con-
figuration, grades, joints, filter layer place-
ment and final flushing;
Granular drainage layer placement, in-
cluding protection of underlying liners,
thickness, overlap with filter fabrics and
geonets;
3-40
-------
SECTION 3
Construction Quality Assurance
Geonet placement, including layout, over-
lap and protection from clogging by
granular material carried by wind or run-
off during construction;
Geotextile/geofabric placement, includ-
ing coverage and overlap;
Sumps and structure installation; and
Mechanical and electrical equipment in-
stallation, including testing.
In addition to field observations, actual field and
laboratory testing may be performed to docu-
ment that the materials meet the design specifi-
cations. These activities should be documented
and should include the following:
Geonet and geotextile sampling and testing;
Granular drainage and filter layer sam-
pling and testing for grain size distribu-
tion; and
Testing of pipes for leaks, obstructions,
and alignments.
Upon completion of construction, each compo-
nent should be inspected to identify any damage
that may have occurred during its installation, or
during construction of another component (e.g.,
pipe crushing during placement of granular drain-
age layer). Any damage that does occur should
be repaired, and these corrective measures
should be documented in the CQA records.
3-41
-------
SECTION 3
Construction Quality Assurance
References
1. National Archives and Records Administration, Federal Register. Vol. 58
(Washington, D.C.: GPO, October 1, 1993) p. 53136.
2. U.S. Environmental Protection Agency, Requirements for Hazardous
Waste Landfill Design. Construction, and Closure. EPA/625/4-89/022
(Cincinnati, OH: GPO, 1989).
3. U.S. Environmental Protection Agency, Design and Construction of
RCRA/CERCLA Final Covers. EPA/625/4-91/025 (Cincinnati, OH: GPO, 1991).
4. U.S. Environmental Protection Agency, Guide to Technical Resources for
the Design of Land Disposal Facilities. EPA/625/6-88/018 (Cincinnati, OH:
GPO, 1988).
5. U.S. Environmental Protection Agency, Lining of Waste Containment and
Other Impoundment Facilities. EPA/600/2-88/052 (Cincinnati, OH: GPO,
1988).
6. U.S. Environmental Protection Agency, Seminars - Design. Operation and
Closure of Municipal Solid Waste Landfills. EPA/600/K-92/002 (April
1992).
7. Robert Koerner. Designing With Geosvnthetics (1990^.
8. U.S. Environmental Protection Agency, Solid Waste Disposal Facility Cri-
teria. Technical Manual. EPA 530-R-93-017 (November 1993).
9. U.S. Environmental Protection Agency, Technical Guidance Document:
Inspection Techniques for the Fabrication of Geomembrane Field Seams.
EPA/530/SW-91/051 (May 1991).
10. U.S. Environmental Protection Agency, Seminars - Design and Construc-
tion of RCRA/CERCLA Final Covers. CERI 90-50 (1990).
11. U.S. Environmental Protection Agency, Technical Guidance Document:
Quality Assurance and Quality Control for Waste Containment Facilities.
EPA/600/R-93/182 (September 1993).
3-42
-------
-------
SECTION 4.0
Landfill Gas Monitoring and Management
Page No.
4.1 INTRODUCTION 4-1
4.2 LANDFILL GAS GENERATION 4-1
4.2.1 Gas Composition 4-2
4.2.2 Gas Characteristics 4-3
4.2.2.1 Methane 4-3
4.2.2.2 Carbon Dioxide 4-3
4.2.2.3 Hydrogen Sulfide 4-4
4.2.3 Gas Generation Phases 4-4
4.2.3.1 Aerobic Decomposition (Phase I) 4-5
4.2.3.2. Anaerobic Non-methanogenic Decomposition
(Phase II) 4-5
4.2.3.3 Anaerobic Methanogenic Decomposition
(Phase III) 4-5
4.2.3.4 Anaerobic (Steady-state) Methanogenesis
(Phase IV) 4-7
4.2.4 Factors Controlling Gas Generation 4-7
4.2.4.1 Moisture Content 4-7
4.2.4.2 Organic Content 4-8
-------
Page No.
4.2.4.4 Time Since Waste Placement and Aerobic
Versus Anaerobic Conditions 4-8
4.3 GAS MIGRATION 4-8
4.3.1 Gas Migration Mechanisms 4-8
4.3.2 Factors Affecting Gas Migration 4-9
4.4 GAS DETECTION MONITORING 4-13
4.4.1 Gas Detection Monitoring Program 4-13
4.4.2 Monitoring System Design Factors 4-14
4.4.3 Detection Monitoring Locations 4-15
4.4.3.1 Ambient Conditions 4-15
4.4.3.2 Structures 4-16
4.4.3.3 Subsurface Sampling 4-16
4.4.3.4 Subsurface Gas Monitoring 4-18
4.5 PASSIVE AND ACTIVE GAS MANAGEMENT SYSTEMS 4-19
4.5.1 Passive Gas Management Systems 4-20
4.5.1.1 Open Ditches 4-20
4.5.1.2 Vent Trenches 4-20
4.5.1.3 Impermeable Barriers 4-21
4.5.1.4 Vent Layers and Vertical Vents (Wells) . 4-21
4.5.1.5 Substructure Vents 4-24
-------
Page No.
4.5.1.6 Active Gas Management Systems .... 4-24
4.5.1.7 Extraction Systems (Trenches and/
or Wells) 4-25
4.5.1.8 Injection Barriers 4-28
4.5.1.9 Substructure Extraction 4-28
4.6 GAS MANAGEMENT SYSTEM OPERATION AND MONITORING 4-28
4.6.1 Primary Gas Extraction Well Fields 4-29
4.6.2 Perimeter Gas Migration Control Systems 4-31
REFERENCES 4-32
List of Figures Page No.
4-1 Evolution of Typical Landfill Gas Composition 4-6
4-2 Vertical and Lateral Migration 4-10
4-3 Landfill Migration Pathways 4-12
4-4 Typical Landfill Gas Monitoring Well/Probe 4-17
4-5 Typical Passive Vent Layer Gas Management System 4-22
4-6 Vent Layers and Vertical Vents (Wells) 4-23
4-7 Typical Gas Extraction Well 4-26
4-8 Typical Gas Extraction Trench and Header 4-27
4-9 Typical Primary Gas Extraction Wellfield System 4-30
-------
SECTION 4
Landfill Gas Monitoring and Management
=U- Unmanaged landfill gas can not only be a hazard
INTRODUCTION to human health and the environment but can
also cause structural problems to the landfill de-
sign components. Landfill gas, if allowed to accu-
mulate, can result in fire, explosion and
breathing conditions which are Immediately Dan-
gerous to Life and Health (IDLH). Landfill gas
can also cause odor problems and have detri-
mental effects on vegetation.
EPA's Subtitle D regulations require routine
monitoring for methane gas accumulation and mi-
gration. The regulations also require that meth-
ane concentrations be maintained below certain
levels with respect to the LEL. If regulatory ac-
tion levels are exceeded, specific actions must
be taken including the following: implementing
immediate steps to protect human health, record-
ing the concentrations and other pertinent infor-
mation (i.e., field observations, pertinent facility
design information and actions taken) in the offi-
cial operating record of the landfill, implementing
a remediation plan and notifying the appropriate
regulatory authority (EPA or the state agencies
where EPA has approved the state program) of
the event within a specified time frame.
This section discusses the origin and components of
the engineering systems utilized to monitor and man-
age landfill gas.
4.2 Landfill gas generation is primarily a result of bio-
LANDFILL GAS logical decomposition of the organic components
GENERATION was*e- Municipal solid waste is estimated
to be approximately 50 percent organic material
(i.e., paper, food and agricultural/yard wastes).
4-1
-------
SECTION 4
Landfill Gas Monitoring and Management
4.2.1 The two principal components of landfill gas are
Gas Composition carbon dioxide (CO2) and methane (CH4). Minor
amounts of hydrogen sulfide (H2S), hydrogen
(H2), mercaptans and volatile organic com-
pounds may also begenerated or released from
the wastes.
The composition of gas generated in a landfill var-
ies according to whether generation occurs in aero-
bic (oxygen-rich) or anaerobic (oxygen-poor)
conditions. Composition also varies over time until
long term, steady-state conditions are established.
Under aerobic conditions, organic sub-
stances and oxygen are metabolized to
yield carbon dioxide, water and heat, as
shown in the following equation:
Organic substances [C6H12O6] + O2
CO2 + H2O + heat
Under anaerobic conditions, organic sub-
stances are first metabolized to organic ac-
ids and then methane and carbon dioxide,
as shown in the following equation:
Organic substances [C6H12O6] Organic
Acids [COOH] CH4 + CO2
Methane, which is the principal component of
natural gas (95 to 99 percent), is of primary con-
cern with respect to landfill gas generation be-
cause it is combustible and flammable.
Hydrogen, which is also combustible, is present
at much lower concentrations because it readily
reacts to form methane and hydrogen sulfide.
-------
SECTION 4
Landfill Gas Monitoring and Management
4.2.2
Gas Characteristics
The properties of methane, carbon dioxide and
hydrogen sulfide, the most common landfill
gases, may be summarized as follows"
4.2.2.1
Methane
In addition to the characteristics described, methane:
Is colorless
Is odorless or may have a weak odor of
marsh gas
Is tasteless
Is a simple asphyxiant (excludes O2)
Reacts violently with powerful oxidizers
Is lighter than air (molecular weight
16.05)
Is soluble in water
Has a LEL 5 percent by volume in air
Has an Upper Explosive Limit (UEL) 15
percent by volume in air
4.2.2.2
Carbon Dioxide
Commonly produced in landfills, carbon dioxide:
Is noncombustible and nonflammable
Is colorless
Is odorless
Is an asphyxiant (excludes O2)
4-3
-------
SECTION 4
Landfill Gas Monitoring and Management
Is heavier than air (molecular weight
44.01)
4.2.2.3 A third gas found in landfills, hydrogen sulfide
Hydrogen Sulfide
Is flammable
Is colorless
Has an offensive odor of rotten eggs
[threshold detection concentration 5
parts per billion (ppb)]
Is an olfactory desensitizer and rapidly di-
minishes ability to smell
Is a very poisonous gas [IDLH 300 parts
per million (ppm)]
Is an irritant to eyes and mucous mem-
branes
Is an asphyxiant
Is slightly heavier than air (molecular
weight 34.08)
Has a LEL 4 percent by volume in air
Has an UEL 46 percent by volume in air
4.2.3 Landfill gas generation occurs in the following
Gas Generation Phases four phases, with methane being generated in
the last two:
Phase I - Aerobic Decomposition
Phase II - Anaerobic Non-Methanogenic
Decomposition
-------
SECTION 4
Landfill Gas Monitoring and Management
Phase III - Anaerobic Methanogenic De-
composition
Phase IV - Anaerobic (Steady-State)
Methanogenesis
Each of these phases is described in the sec-
tions that follow. A graph showing the evolution
of typical landfill gas composition is presented in
Figure 4-1.
4.2.3.1 Aerobic decomposition begins prior to placing
Aerobic wastes in the landfill and continues until the oxy-
Decomposition(Phase I) gen which is entrapped in the voids during place-
ment and compaction is expended. This process
can take several weeks or longer depending
upon oxygen replenishment and/or displace-
ment. Decreasing oxygen concentrations reduce
both the biological activity and numbers of aero-
bic microorganisms.
4.2.3.2
Anaerobic
Non-Methanogenic
Decomposition (Phase II)
As oxygen becomes depleted, aerobic microor-
ganisms are replaced by anaerobes (anaerobic
microorganisms). This phase, which can last for
several weeks, is characterized by increasing
carbon dioxide concentrations (which may ap-
proach 65 percent), hydrogen generation and de-
creasing nitrogen concentrations and heat.
4.2.3.3
Anaerobic
Methanogenic
Decomposition (Phase III)
The anaerobic methanogenic phase begins with
the production of methane. This phase, which may
last for weeks or months, is characterized by a
rapid rise in methane concentrations to replace
carbon dioxide as the primary gas component, a
continuing decline in the nitrogen concentration
and depletion of hydrogen.
4-5
-------
ฃ
sj
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5?
s-
a
3"
-------
SECTION 4
Landfill Gas Monitoring and Management
4.2.3.4
Anaerobic (Steady-
State) Methanogenesis
(Phase IV)
The methanogenesis (methane-generating) phase,
which typically begins within the first 2 years after
waste placement, results in decades-long steady-
state methane generation with concentrations rang-
ing between 45 to 65 percent. The other primary gas
components of this phase are carbon dioxide (35 to
50 percent) and small percentages of nitrogen.
4.2.4
Factors Controlling
Gas Generation
The rate and composition of landfill gas generated is
dependent upon several factors:
Moisture content
Organic content
Temperature and pH
Time since waste placement
Aerobic versus anaerobic conditions
4.2.4.1 The highest methane gas generation rates occur
Moisture Content at moisture contents ranging from 60 to 80 per-
cent of saturation and under anaerobic condi-
tions. Modern landfill design requirements
(synthetic caps) minimize infiltration of water
while creating anaerobic environments. Optimum
moisture content may never be achieved or main-
tained in these facilities, resulting in reduced
methane production rates over time. This can be
beneficial in controlling gas production.
Decreased methane production may, however,
affect the viability of gas (energy) recovery sys-
tems installed at the landfill. Gas production can
be increased through strategies such as
leachate recirculation which distributes bacteria,
nutrients and moisture more uniformly within the
waste.
4-7
-------
SECTION 4
Landfill Gas Monitoring and Management
4.2.4.2
Organic Content
Organic content of the waste is another impor-
tant factor in gas generation. Methane gas gen-
eration is generally higher in municipal solid
waste landfills than in construction/demolition
landfills and inert industrial landfills (i.e., mining
waste, fly ash and inorganic waste landfills).
4.2.4.3
Temperature and pH
Landfill temperature and pH are other factors
which can affect gas generation. Methane gas
generation is optimal at temperatures of 90 to
110ฐ F and within a pH range from 6.5 to 8.0.
Methanogenic microorganism activity can be sig-
nificantly reduced at lower temperatures and/or
lower pH.
4.2.4.4
Time Since Waste
Placement and Aerobic
Versus Anaerobic
Conditions
The impacts of time and aerobic versus anaero-
bic conditions on gas generation were discussed
in Section 4.2.3, Gas Generation.
4^3
GAS MIGRATION
4.3.1
Gas Migration
Mechanisms
Gases are transported by convection and diffu-
sion. Convection is a migration mechanism in-
duced by pressure gradients. Gases move from
areas of high pressure to those of low pressure
following the "path of least resistance." Convec-
tion resulting from buoyancy forces (methane is
lighter than carbon dioxide and air) is not as sig-
nificant a factor because methane and carbon di-
oxide are formed as a gas mixture with a density
roughly equal to air. This gas mixture does not
readily separate and allow methane to migrate in-
dependent of the carbon dioxide.
4-8
-------
SECTION 4
Landfill Gas Monitoring and Management
4.3.2
Factors Affecting Gas
Migration
Diffusion is the migration of gases in response to
concentration gradients. Gases will seek a uni-
form concentration distribution throughout the
voids, moving from areas of higher concentration
to those of lower concentration. Anaerobic de-
composition produces a gas mixture with concen-
trations of methane and carbon dioxide that are
much higher than those found in the surrounding
air which can result in diffusion of gases through
permeable (soil) landfill covers. However, uniform
gas distribution is hindered by physical resistance
to migration (low permeability or saturated layers).
Variable rates of gas generation throughout the
landfill also result in nonuniform gas distribution.
Generally, diffusion plays a much smaller role in
gas migration than convection.
Landfill gases will migrate by convection and/or dif-
fusion, vertically if there are no horizontal barriers,
or horizontally along more permeable layers within
the landfill. Permeable waste layers surrounded by
low permeability or saturated layers create prefer-
ential horizontal pathways for gas migration.
Gas migration, the movement of gas within and
out of a landfill, is affected by the rate of gas pro-
duction and physical conditions inside and
around the landfill. Low hydraulic conductivity
soil layers and landfill liners are effective barriers
to gas migration, while sand and gravel layers
and void spaces provide effective corridors for
channeling gas migration (Figure 4-2). Other
channels for migration are cracks and fissures
between and in lifts of waste due to differential
settlement and subsidence.
Corridors at or adjacent to the landfill such as sand
and gravel lenses, water conduits, drain culverts
and buried utility lines can promote uncontrolled
4-9
-------
Vertical and Lateral Migration
o
o
to
e
Cr
CJ;
S
s
3-
a
I
s1
3"
3"
3
C
0)
Clay or Synthetic Cap
(Low Permeability)
Clay Soil, Frozen or
Saturated Soil, or Pavement
(Low Permeability)
Sand and Gravel Soil.
(High Permeability)
LATERAL MIGRATION
VERTICAL MIGRATION
(Modified EMCO, 1981)
Figure 4-2
-------
SECTION 4
Landfill Gas Monitoring and Management
gas migration. Barriers which can impede gas mi-
gration include clay deposits, high or perched
water tables, roads and compacted, low perme-
ability soils. Figure 4-3 presents a three-dimen-
sional view of a landfill and features affecting
potential migration pathways.
Some landfill design and operation factors which
affect gas migration are:
Landfill liner design
Staging of cell construction
Operation of leachate collection systems
Incorporation of gas migration control
measures
Final cover design
Other climatic and seasonal factors which may
cause variations in gas migration include the fol-
lowing:
Intermittent occurrence of saturated or fro-
zen surface soils which seals the surface
and promotes lateral migration
Barometric pressure changes which af-
fect the rate of gas release to the surface
and can induce preferential migration
along different pathways
Seasonal changes in moisture content
which can change gas production rates
and therefore the extent and quantity of
migration
4-11
-------
Landfill Migration Pathways
ro
*
O
in
c
o*
Cfc
ง=
ง
3
8'
3
3"
IQ
I
3
C
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HEADER PIPE
(Source: EPA, 1993)
Figure 4-3
-------
SECTION 4
Landfill Gas Monitoring and Management
4.4
GAS DETECTION
MONITORING
4.4.1
Gas Detection
Monitoring Program
Infiltrating water which can displace
gases in the voids and change preferen-
tial migration pathways
Changes in soil temperature which affect
the pressure gradient
A methane gas detection monitoring program
must be implemented at all regulated MSWLFs
(new, existing and lateral expansions). The rou-
tine monitoring program must ensure that meth-
ane concentrations
Do not exceed 25 percent of the LEL
(25% of 5% = 1.25% by volume in air) in
facility structures excluding gas manage-
ment system components, and :
Do not exceed the LEL (5 percent by vol-
ume in air) at the facility property bound-
ary.
At a minimum, quarterly methane gas monitoring
is required for detection purposes. More frequent
monitoring may be required based upon site con-
ditions, such as:
Increasing methane concentrations at de-
tection monitoring locations
Operational changes for methane gas
control systems
Operational changes for leachate collec-
tion and recirculation systems
4-13
-------
SECTION 4
Landfill Gas Monitoring and Management
4.4.2
Monitoring
SystemDesign Factors
Landfill design changes (i.e., capping, clo-
sure or expansion)
Hourly or continuous methane detection monitoring
may be necessary if the methane concentrations
exceed the limits listed above. Under these condi-
tions, the regulations also require that the following
specific actions be taken within the time frames
stated:
Immediately - All necessary steps to en-
sure protection of human health. At a
minimum, these include evacuation of
personnel from the facility and notifica-
tion of appropriate authorities responsi-
ble for dealing with explosive
emergencies. Notify the State Director.
Within 7 Days - Place the methane gas-
level data and description of steps taken
to protect human health in the operating
record.
Within 60 Days - Prepare and imple-
ment a remediation plan that describes
the nature and extent of the problem
and the proposed remedy. Place the re-
mediation plan in the operating record
and notify the EPA or the State Director
that the plan has been implemented.
The spacing and number of monitoring system
sampling locations is unspecified in the regula-
tions; however, they must be sufficient to provide
for detection of gas migration and be protective
of human health and the environment. The fre-
quency of monitoring and the number of loca-
tions is a site-specific consideration which should
be based upon
4-14
-------
SECTION 4
Landfill Gas Monitoring and Management
4.4.3
Detection Monitoring
Locations
4.4.3.1
Ambient Conditions
Soil conditions (i.e., porosity, permeabil-
ity and moisture content);
Hydrogeologic conditions (i.e, thickness
of unsaturated zone, continuity of perme-
able units and presence of impermeable
barriers);
Hydraulic conditions (i.e., depth to ground-
water, infiltration potential and groundwater
discharge and recharge zones);
Facility design and changes (i.e., phas-
ing of construction, installation of a cap,
whether facility is lateral or vertical ex-
pansion);
Location of facility structures;
Location of property boundaries;
o Location of adjacent property structures;
and
Adjacent land uses.
Ambient conditions should be monitored both as a
safety precaution and to detect other sources of
methane gas release. Ambient readings for meth-
ane and oxygen should be monitored before open-
ing or entering any enclosed structures (wells
and/or buildings). Monitoring should also be con-
ducted while opening and prior to entering confined
spaces at landfills (i.e., leachate and gas collection
system entryways).
4-15
-------
SECTION 4
Landfill Gas Monitoring and Management
Ambient readings may indicate methane accumu-
lation or releases from other facilities or nearby
features, such as:
Marshes, swamps and wetlands;
Natural gas pipelines;
Sewer lines; and
Methane generating geologic formations.
4.4.3.2 Facility structures where gas may accumulate
Structures must be included in the monitoring program.
EPA's definition of the term "structure" is broad
and includes
Pump houses
Storage sheds
Basements and crawl spaces
Culverts and drains
Any other buildings or structures where
vertically or horizontally migrating gases
can become trapped
4.4.3.3. Two types of subsurface gas monitoring installa-
Subsurface Sampling tions are commonly used: methane gas wells
and gas probes. Figure 4-4 shows comparative
features of gas wells and gas probes. Methane
gas monitoring wells and/or probes are used to
monitor gas migration between the landfill and
the property boundary. Gas monitoring wells are
similar in construction to groundwater monitoring
wells, with granular permeable material adjacent
to the screened interval and an annular seal to
4-16
-------
Typical Landfill Gas Monitoring
Well/Probe
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-------
SECTION 4
Landfill Gas Monitoring and Management
4.4.3.4.
Subsurface Gas Monitoring
the surface. However, gas wells do not penetrate
the water table; the screened interval is located
within the unsaturated zone.
Gas probes are also installed in boreholes, al-
though they are constructed with a probe tip or
short interval of screen which is connected to the
surface by a small-diameter tube. The monitoring
interval of the gas probe is generally smaller
than that of gas wells.
Proper sampling techniques are essential to a
gas monitoring program. Since gas monitoring
wells are installed with relatively large-diameter
casings (i.e., 2-inch pipe), gas concentrations
within the well casing riser may not be repre-
sentative of gas concentrations in the unsatu-
rated media, necessitating evacuation of gases
from the well prior to sampling. Such evacuation
will help assure that gas readings are repre-
sentative of gas concentrations migrating
through the subsurface. When evacuating wells
with a vacuum pump, the surface annulus
around the evacuation line must be sealed. Oth-
erwise, the induced vacuum will pull air in from
the atmosphere (following the path of least resis-
tance) and not from the unsaturated zone.
Evacuation may not be necessary for gas probes
because of the small diameter of the tubing and
the surface seal. The monitoring instrument
pump can evacuate these small gas volumes
and collect representative samples.
Other considerations which must be addressed in
the subsurface gas monitoring program are instru-
mentation and oxygen and water vapor concentra-
tions. The gas mixture in the subsurface media
may be oxygen-deficient, particularly if water vapor
4-18
-------
SECTION 4
Landfill Gas Monitoring and Management
4J>
PASSIVE AND
ACTIVE GAS
MANAGEMENT
SYSTEMS
concentrations are high as commonly occurs af-
ter rainfall events. Under such oxygen deficient
conditions, instruments which measure methane
by combustion (i.e., flame ionization detectors)
may not provide accurate results if oxygen con-
centrations are below the range which will sup-
port combustion (19.5 to 25 percent). The
measurement of oxygen content is essential to
proper selection and operation of monitoring in-
struments.
A variety of technologies are available for control-
ling landfill gas accumulation and migration. Landfill
gas management systems are designed for two
purposes: extracting gas from the landfill and con-
trolling gas migration. Two types of systems, pas-
sive and active, are used depending upon the gas
management purpose and rate of gas accumula-
tion and migration.
The type of gas management system required is
dependent upon the gas management objectives
(gas removal or migration control) and a number
of site factors including:
Landfill size and age;
Facility design (lined, capped or covered);
Type of waste (organic content of waste);
Waste volume and thickness; and
Local conditions (geology, site features,
adjacent land use and demographics).
Care must be taken in designing gas control sys-
tems, especially passive systems, to prevent
them from providing a pathway for unwanted infil-
tration of surface water. Improper design could
4-19
-------
SECTION 4
Landfill Gas Monitoring and Management
allow the vent to intercept surface runoff and
pipe additional infiltration into the landfill and
leachate collection system.
4.5.1
Passive Gas
Management Systems
Passive gas management systems rely upon the
natural forces of convection and diffusion to con-
trol landfill gas migration. Passive systems are
designed to create preferential pathways for gas
migration, collection and venting at controlled dis-
charge points. Examples of passive gas manage-
ment systems include the following:
Open ditches
Vent trenches
Impermeable barriers
Vent layers and vertical vents (wells)
Substructure vents
4.5.1.1
Open Ditches
Open ditches can be used to provide for venting
of laterally migrating gases at the perimeter of
the landfill or between the landfill and the prop-
erty boundary. The use of open ditches within
the landfill disposal area is difficult considering
the new requirements for daily cover and
leachate management. The use of open ditches
outside the disposal area may still be practical
for controlling lateral gas migration. The effective-
ness of these simple installations is also depend-
ent upon the depth of the landfill, depth of the
ditch and depth, thickness and permeability of
the migration pathway.
4.5.1.2
Vent Trenches
Passive vent trenches are designed and con-
structed either to prevent lateral migration of landfill
gas or to collect the gas from within the landfill.
4-20
-------
SECTION 4
Landfill Gas Monitoring and Management
Gravel-filled vent trenches are better than open
ditches at passively venting laterally migrating landfill
gas. Open vent trenches used for lateral migration
control are often constructed with impenetrable barri-
ers on the outer side of the trench, away from the
methane source, to prevent migration of the landfill
gas to the surrounding area.
Like open ditches, vent trenches present prob-
lems when installed within the landfill. Vent lay-
ers (discussed below) are preferable because
they are designed with impenetrable barriers
above the permeable layer to prevent infiltration.
Vent trenches installed outside the landfill waste
disposal area often extend from the surface
down to a low hydraulic conductivity soil layer or
other barrier such as the water table or a Flex-
ible Membrane Liner. These systems may be in-
stalled as deep as the bottom of the landfill if
outside the waste disposal area. Cost, related to
depth of installation, becomes a limiting factor in
the effective application of this passive system.
4.5.1.3 Impermeable barriers such as slurry walls can be
Impermeable Barriers used to create a barrier to gas migration. Other
materials which also create impermeable barri-
ers and could be used to prevent lateral gas mi-
gration are Flexible Membrane Liners or water
infiltration barriers (i.e., constructed wetlands or
stormwater retention/infiltration ponds).
4.5.1.4 Vent layers and vertical vents are gas manage-
Vent Layers and rnent system components which are commonly
Vertical Vents (Wells) installed within the landfill for either passive or ac-
tive gas removal purposes (figures 4-5 and 4-6).
Passive gas management systems may incorpo-
rate vent layers constructed of highly permeable
material (i.e., gravel), composite covers and verti-
4-21
-------
Typical Passive Vent Layer Gas
Management System
Gas Vent
/ // // // ซ * * ' ' mz * * / f / /
^/V/V/VAVV/ Perforated Pipe \V,V
>ป^/////////////< ' ' \
^ ,/ / ////
-------
Vent
Layers and Vertical Vents (Wells)
*
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CO
O
C/>
c
o-
Ch
ฃ
5*
3-
3
I
3*
3"
(Q
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C
01
Gravel Pack
(a) Open Trench
ft
[Capjxg^
.Gravel
Pack
(b) Open Trench with Liner
fib (r&
Side View Front View
(c) Closed Trench with Lateral and Risers
IE-7 Clay IS
Clay
Gravel Pack
(d) Induced Draft
(e) Air Iniection
(Source: EPA, 1982)
Figure 4-6
-------
SECTION 4 Landfill Gas Monitoring and Management
cal vents to release gas from the landfill. The
composite cover prevents uncontrolled vertical
migration, while the vent layer intercepts verti-
cally migrating gas and directs it to the surface
via vent pipe(s) that are installed along the high
point of the waste cell. The vertical vents (wells)
may extend deeper into the landfill to provide a
vertical migration pathway for gas to enter the
vent layer from deeper layers within the landfill.
These systems induce landfill gas to migrate ver-
tically rather than laterally.
4.5-1 1-5 Substructure vent systems can be installed to
Substructure Vents prevent gases from accumulating beneath struc-
tures. Passive substructure vent systems require
placement of a permeable system (piping and
gravel layer) beneath the foundation slab of the
structure to provide a preferential pathway for
gas venting, thereby preventing migration of land-
fill gas into the structure. The gas must be
vented away from the structure to prevent accu-
mulation in other traps (i.e., overhangs, utility
closets or the structure itself).
4.5-1,6 Active gas management (extraction) systems
Active Gas Management use mechanical components to control and col-
Systems lect landfill gas. Active systems create positive or
negative pressure gradients to drive the landfill
gas to the point of extraction. Examples of active
gas management systems include the following:
Extraction systems (trenches and/or
wells)
Injection barriers
Substructure extraction
4-24
-------
SECTION 4
Landfill Gas Monitoring and Management
4.5.1.7
Extraction Systems
(Trenches and/or Wells)
In order to be effective, active gas extraction sys-
tems must be designed to draw gas from
throughout the landfill and not preferentially from
air infiltration conduits. Factors which must be
considered in designing active gas extraction
systems include the following:
Facility design (lined and unlined cells);
Disposal practices (waste disposal in dis-
crete cells); and:
Thickness of the landfill (highest methane
generation potential is in the center of the
landfill where waste placement is thicker).
Active gas extraction systems may include a se-
ries of trenches and/or wells with collection head-
ers for extracting gases from deeper layers
within the landfill. Trenches are generally em-
ployed as perimeter gas extraction systems or at
shallow depths within the landfill while wells are
more practical as primary extraction systems in
the thickest portions of the landfill. The well cas-
ings and/or piping installed within the trenches
are connected to extraction blowers or pumps.
Typical active gas extraction wells and trenches
are shown in figures 4-7 and 4-8. Gas extraction
wells do not have to extend to the bottom of the
landfill since suction applied to the system is
able to draw gas from a sizeable area beyond the
gravel pack which surrounds the well screen.
Impermeable barriers in the cover and landfill pe-
rimeter walls increase the efficiency of active gas
extraction systems since they restrict inflow of air
that would dissipate the suction. These barriers
also reduce the number of wells and/or trenches
4-25
-------
Typical Gas Extraction Well
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51
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a
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3"
Soil or ฃ3
Refused
j^-Valve kg
4" PVC Lateral
F> IH*
fi"
3*ซSl?rW?C
Cas Collection
Header
Bentonite or
Concrete
4" PVC Pipe
1"+
Crushed Stone
4" PVC
Perforated Pipe
Cap
1!
rrrf-fy- J
r
rV'-..-.
ฆVA-'.-v
Kv.-y.
v/*v\
pa/.%
C V':
1
\ \
/;ฆ /,< ~
\V-vV*.\
&W/
o ฆ##;
3$$
irt
U
+J
uj
lZ
V
4->
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re
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re
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0)
;M
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v
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re
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(Source: SCS, 1980)
Figure 4-7
-------
Typical Gas Extraction
Existing Cover
Existing Cover-
-Refuse-
Trench and Header
Ni
vi
*
0
ง
(/)
งฆ
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CD*
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3'
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C
0)
Ceotextile
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Pi
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Pipe
O o*
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Bottom of Trench Excavation
(Source: SWANA, 1991)
Washed Cravel
o
O O
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Perforated Pipe
o
Flexible Hose
Butterfly Valve
Header Riser ^
^ Existing
Covert
Seal
Washed Cravel
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. Quick Connect
Coupling
Orifice Plate
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Pipe
Figure 4-8
-------
SECTION 4
Landfill Gas Monitoring and Management
needed and increase the heating value of the
gas collected.
Gas extraction systems should be designed so that
portions of the system can be disconnected or shut
off as necessary to adjust for increased infiltration of
surface air due to active disposal or insufficient or
permeable cover. If properly designed and operated,
methane gas extraction systems can be used for en-
ergy production or as the primary fuel for a flare.
4.5.1.8
Injection Barriers
Injection of air or water can be used as an active
mechanism to restrict lateral migration of landfill
gases. Air injection systems are installed in a per-
pendicular direction to the gas migration path-
way. Air is injected through a header system to
create a subsurface pressure gradient which re-
stricts or reverses the direction of gas migration.
Water injection barriers are not commonly used
for gas migration control; however, infiltration gal-
leries can be used to impede gas migration at
shallow depths.
4.5.1.9
Substructure
Extraction
Active substructure extraction systems are similar
to passive substructure venting systems, but are
more effective in providing for controlled removal of
gases. Active substructure extraction systems can
also be designed for short-term remediation pur-
poses where thesystem is installed above the slab
(in basements or crawl spaces).
4.6
GAS MANAGEMENT
SYSTEM OPERATION
AND MONITORING
Gas management systems are constructed and
operated both within the landfill (primary well-
fields) and at the perimeter of the landfill (either
inside or outside of the landfill waste disposal
area). Both types of systems must be monitored
for optimal performance.
4-28
-------
SECTION 4
Landfill Gas Monitoring and Management
4-p.i Primary (interior) gas extraction wellfields are the
Primary Gas most efficient and often the largest component of
Extraction Wellfields a comprehensive gas extraction system. Their
function is to collect most of the landfill gas at
the point of generation (within the landfill.) Extrac-
tion wellfield systems normally include a number
of wells spaced evenly over the entire landfill
(Figure 4-9). Spacing and design of the extrac-
tion well field is dependent upon landfill design
(lined or unlined), waste voids and layering and
landfill cell configuration. Separate extraction
well systems may be necessary to segregate
gas extraction from high and low methane gen-
eration areas.
Improper operation of gas extraction well sys-
tems can result in excess emissions of landfill
gas to the atmosphere, gas migration and over-
pulling of the wellfield which can disrupt anaero-
bic decomposition or cause subsurface fires.
The frequency of gas extraction wellfield monitor-
ing will vary depending upon field requirements
and conditions. Normal monitoring frequency for
a complete field monitoring program will vary
from once a week to once a month. Wellfield
monitoring should not normally be extended be-
yond once a month, especially on active landfills.
Too many things can happen which can result in
inefficient or detrimental operation of the gas ex-
traction system.
The importance of regular, timely and thorough
monitoring cannot be overemphasized. Improper
operation of the primary gas extraction wellfield
system puts additional requirements on perime-
ter gas migration control systems.
4-29
-------
-------
SECTION 4
Landfill Gas Monitoring and Management
4.6.2
Perimeter Gas Migration
Control Systems
Perimeter gas migration control systems extract
poor quality landfill gas that is often high in oxy-
gen due to air intrusion at the interface of the
landfill and the native soil. Operating objectives
for the perimeter system are different than for
the primary gas extraction wellfield system. The
perimeter system provides a final opportunity to
capture gas before it escapes from the landfill
and migrates to adjacent properties or structures.
Perimeter gas migration control systems may be
installed within the landfill near the perimeter or
in native soil adjoining the landfill depending
upon the design objectives for controlling gas mi-
gration. Gas migration pathways can change
drastically at the perimeter, making gas quality
and control difficult. For this reason, perimeter
gas wells or trenches are often tied into a sepa-
rate extraction system.
Perimeter gas management systems generally re-
quire more frequent monitoring on a weekly or
even daily basis depending upon the methane con-
centration of the migrating gas. The danger of sub-
surface fires, caused by air intrusion, is more
significant where perimeter gas management sys-
tems are operated at high extraction rates.
Landfill gas migration is usually decreased if the
primary gas management system pulls gas toward
the center of the landfill instead of allowing the landfill
gas to be pulled toward the perimeter system. The
perimeter migration system, then, only has to extract
locally generated gas rather than gas already migrat-
ing towards the perimeter of the landfill.
4-31
-------
SECTION 4
Landfill Gas Monitoring and Management
References
1. U.S. Environmental Protection Agency, Design and Construction of
RCRA/CERCLA Final Covers. EPA/625/4-91/025 (Cincinnati, OH: GPO,
1991).
2. U.S. Environmental Protection Agency, Design. Operation and Closure of
Municipal Solid Waste Landfills. EPA/600/K-92/002 (Washington, DC:
GPO, 1992).
3. U.S. Environmental Protection Agency, Requirements for Hazardous
Waste Landfill Design. Construction, and Closure. EPA/625/4-89/022 (Cin-
cinnati, OH: GPO, 1989).
4. Landfill Control Technologies, Technical Tips, Bulletin #102 (1992)
5. N. Irving Sax, and Richard J. Lewis, Dangerous Properties of Industrial
Materials. Seventh Edition (New York, NY: Van Nostrand Reinhold, 1989).
6. U.S. Department of Transportation, U.S. Coast Guard, Chemical Hazards
Response Information System (CHRIST Manual. M16465.11a (Washing-
ton, DC: 1985).
7. Solid Waste Association of North America, Landfill Gas Division: A Compi-
lation of Landfill Gas Field Practices and Procedures (March 1987).
8. Commonwealth of Pennsylvania, Department of Environmental Re-
sources Bureau of Waste Management, Guidance Manual for Landfill
Gas Management (September 1986).
9. U.S. Environmental Protection Agency, Virginia Landfill Training. EPA
Contract No. 68-W0-0025, WA No. 253 (1993).
10. Emcon Associates. Methane Generation and Recovery from Landfills.
(Ann Arbor, Ml: Ann Arbor Science Publishers, Inc., 1980).
11. G. H. Farquhar, and F.A. Rovers, Gas Production During Refuse Decom-
position. Water. Air and Soil Pollution (1973).
12. U.S. Environmental Protection Agency, Handbook for Remedial Action at
Waste Disposal Sites. EPA/625/6-82/006 (Cincinnati, OH: GPO, 1982).
4-32
-------
-------
SECTION 5.0
Final Cover System
Page No.
5.1 INTRODUCTION 5-1
5.2 REGULATORY REQUIREMENTS 5-1
5.2.1 Minimum Design Requirements 5-1
5.2.2 Alternate Cover Design 5-2
5.2.3 Closure Plan 5-2
5.3 TECHNICAL CONSIDERATIONS 5-4
5.4 TYPICAL COMPONENTS OF A FINAL COVER SYSTEM 5-5
5.4.1 Infiltration Layer 5-7
5.4.2 FML Layer 5-8
5.4.3 Drainage Layer 5-10
5.4.4 Erosion Layer 5-13
5.4.5 Optional Layers 5-15
5.4.5.1 Gas Vent Layer 5-15
5.4.5.2 Biotic Layer 5-18
5.5 NATURAL FACTORS AFFECTING FINAL COVER 5-18
5.5.1 Settlement 5-18
5.5.2 Freeze-Thaw Effects 5-20
-------
5.6 FINAL COVER MONITORING 5-22
5.6.1 Settlement/Subsidence 5-22
5.6.2 Surface Erosion Monitoring or Maintenance 5-24
5.6.3 Air Emissions 5-24
5.7 HELP MODEL 5-25
REFERENCES 5-27
Page No.
List of Figures
5-1 Minimum Final Cover Design 5-3
5-2 Typical Final Cover Design 5-6
5-3 Drainage Layer Options 5-12
5-4 Final Cover Design With Optional Layers 5-16
5-5 Gas Vent Layer 5-17
5-6 Biotic Intrusion 5-19
5-7 Regional Depth of Frost Penetration 5-21
5-8 Threshold Limit Values of Selected Air Contaminants 5-24
5-9 Typical Output Data 5-26
-------
SECTION 5
Final Cover System
5.1 The MSWLF's final cover is subject to stresses
INTRODUCTION from both the natural elements and the landfill it-
self. A poorly designed cover system can result in
the exposure of wastes and uncontrolled releases
of gas and leachate. Section 5 discusses the final
cover requirements of 40 CFR 258 and the meth-
ods available to the engineer to ensure that a well-
designed and maintained final cover is in place.
LZ
REGULATORY
REQUIREMENTS
The Subtitle D Regulations pertaining to final
cover prescribe minimum design requirements,
provide for alternative designs and require prepa-
ration of a closure plan.
5.2.1
Minimum Design
Requirements
The final cover system comprises an erosion
layer underlain by an infiltration layer as follows:
Erosion layer to be a minimum of 6
inches of earthen material that is capa-
ble of sustaining native plant growth; and
Infiltration layer to be a minimum of 18
inches of earthen material that has a per-
meability less than or equal to the perme-
ability of any bottom liner system or
natural subsoils present, or a permeabil-
ity no greater than 1 x 10"5 cm/sec,
whichever is less.
The final cover must have a hydraulic conductiv-
ity less than or equal to any bottom liner system
or natural subsoils present in order to prevent a
"bathtub" effect. This effect occurs when the
cover is more permeable than the bottom liner,
allowing more water to enter the landfill than can
be released, causing the landfill to fill with water
like a "bathtub." In no case can the final cover
5-1
-------
SECTION 5
Final Cover System
have a hydraulic conductivity greater than 1x10"
5 cm/sec regardless of the permeability of the un-
derlying liners or natural soils. If an FML is in the
bottom liner, there must be an FML in the final
cover to achieve a permeability that is less than
or equal to that of the bottom liner (see 57 Fed-
eral Register 28626, June 26, 1992, Figure 5-1).
5.2.2 An alternate final cover design may be approved
Alternate Cover Design by the director of an approved state providing
that it includes the following:
An infiltration layer that achieves a reduc-
tion in infiltration equivalent to the mini-
mum design requirements; and:
An erosion layer that provides protection
from wind and water erosion equivalent
to the minimum design requirements.
5.2.3 a written closure plan must be prepared that de-
Closure Plan scribes the steps necessary to close all MSWLF
units at any point during the active life of the
MSWLF. The closure plan must, at a minimum,
include the following information:
A description of the final cover and the
methods and procedures to be used to in-
stall the cover;
An estimate of the largest area of the
MSWLF unit ever requiring a final cover
at any time during the active life;
An estimate of the maximum inventory of
wastes onsite at any given time over the
active life of the landfill facility; and
5-2
-------
Minimum Final Cover Design
MIN. 18" 1 x 10 5 CM/SEC
MIN. 6" EROSION LAYER
FML
Figure 5-1
-------
SECTION 5
Final Cover System
5.3
TECHNICAL
CONSIDERATIONS
A schedule for completing all activities
necessary to satisfy the closure criteria.
Design criteria for a final cover system should be
selected to
Minimize infiltration of precipitation into
the waste
Promote good surface drainage
Resist erosion
Control landfill gas migration and/or en-
hance recovery
Separate waste from vectors (e.g., ani-
mals and insects)
Improve aesthetics
Minimize long-term maintenance
Protect human health and the environment
Consider final use
The first three points listed above are directly re-
lated to the regulatory requirements. The other
points are typically considered when designing
cover systems for landfills.
Reduction of infiltration in a well-designed final
cover system is achieved through
Good surface drainage and runoff with
minimal erosion
5-4
-------
SECTION 5
Final Cover System
Transpiration of water by plants in the
vegetative cover and root zone
Restriction of percolation through
earthen material
The cover system should be designed to provide
the desired level of long-term performance with
minimal maintenance. Surface water runoff
should be properly controlled to prevent exces-
sive erosion and soil loss. A key to protecting the
cover from erosion is the establishment of a
healthy vegetative layer; however, consideration
must also be given to selecting plant species
that are not deeply rooted because they could
damage the underlying infiltration layer. In addi-
tion, the cover system should be geotechnically
stable to prevent failure, such as sliding, that
may occur between the erosion and infiltration
layers, within these layers or within the waste.
5,4
TYPICAL
COMPONENTS OF A
FINAL COVER
SYSTEM
Although the regulations require that a final cover
comprise an erosion layer and an infiltration layer,
a final cover system, as shown in Figure 5-2, typi-
cally consists of the following four components:
A compacted low-permeability soil layer
(infiltration layer) placed over the waste.
This soil layer is typically 60 cm (24
inches) thick and is required to have a
permeability less than or equal to the bot-
tom liner system;
An FML with a minimum thickness of 20
mils, with bedding material above and be-
low the FML;
5-5
-------
Typical Final Cover Design
vegetative/soil
top layer
drainage layer
low-permeability
FML/soil layer
waste
{
\\l/ \\l/ \\l/ \\l/ \\l/
ฐ * "a V *ซ * ฐ * ฐ ' ป \ '
O 0#0,o ,8ฐป ฐ ซ
0 O
0
o o
C* ^ 0
0 q
C3 ^ 0
60 cm
30 cm
60 cm
filter layer
20-mil FML
(Source: EPA, 1990)
Figure 5-2
-------
SECTION 5
Final Cover System
A drainage layer with a minimum hydrau-
lic conductivity of 1 x 10~2 cm/sec and a
final bottom slope of 2 percent; and
A vegetative layer or soil cover (erosion
layer) with a minimum thickness of 60
cm (24 inches) to promote growth and
minimize erosion.
1 The infiltration layer must be at least 18 inches
Infiltration Layer thick, but is typically 24 inches thick. It must also
consist of earthen material that has a hydraulic
conductivity less than or equal to the hydraulic
conductivity of any bottom liner system or natural
subsoils. MSWLF units with poor or nonexistent
bottom liners possessing hydraulic conductivities
greater than 1 x 10"5 cm/sec must have an infil-
tration layer that meets the 1 x 10~5 cm/sec mini-
mum requirement.
For units that have a composite liner with an
FML, or naturally occurring soils with very low
permeability (e.g., 1x10" cm/sec), the infiltra-
tion layer in the final cover will include a syn-
thetic membrane as part of the final cover.
The earthen material used for the infiltration
layer should be free of rocks, clods, debris, cob-
bles, rubbish and roots that may increase the hy-
draulic conductivity by promoting preferential
flow paths. To facilitate runoff while minimizing
erosion, the surface of the compacted soil
should have a minimum slope of 3 percent and a
maximum slope of 5 percent after allowance for
settlement. It is critical that side slopes, which
are frequently greater than 5 percent, be evalu-
ated for erosion potential.
5-7
-------
SECTION 5
Final Cover System
The infiltration layer is designed and constructed
in a manner similar to that used for soil liners,
with the following differences:
Because the cover is generally not sub-
ject to large overburden loads, the issue
of compressive stresses is less critical
unless post-closure land use will entail
construction of objects that exert large
amounts of stress.
The soil cover is subject to loadings from
settlement of underlying materials. The ex-
tent of settlement anticipated should be
evaluated and a closure and post-closure
maintenance plan should be designed to
compensate for the effects of settlement.
Direct shear tests performed on construc-
tion materials should be conducted at
lower shear stresses than those used for
liner system designs.
The design of a final cover is site-specific and
the relative performance of cover design options
may be compared and evaluated by the HELP
model (see section 5.7).
5.4.2 The minimum thickness of the FML should be no
FML Layer less than 20 mils (0.5 mm). This is generally be-
lieved to be the minimum acceptable thickness
to meet cover objectives and still be sufficiently
rugged to withstand expected stresses during
construction and operation. In many cases, if not
most, the thickness should be greater. If HDPE
is used, the recommended minimum thickness is
60 mils due to difficulties in making consistent
field seams in thinner material. The adequacy of
the selected thickness should be demonstrated
-------
SECTION 5
Final Cover System
by an evaluation considering the type, strength
and durability of the proposed FML material, its
seamability and site-specific factors such as
Types of under- and overlying layers
Stresses of settlement
Expected overburden
Climatic conditions
Subsidence
One of the causes of FML failure in landfill lining
systems is chemical incompatibility, as discussed
in Section 2.0. However, the FML in a final cover
should not come in direct contact with any wastes,
and chemical incompatibility should not be of con-
cern. This makes it possible to accept a wider
range of FML materials in cover systems.
The FML component must have the following
characteristics:
The thickness of the FML should be at
least 20 mils or 60 mils if HDPE.
The surface of the FML should have a
minimum 3-percent slope after allow-
ance for settlement.
There should be no surface unevenness,
local depressions or small mounding that
create depressions capable of containing
or otherwise impeding the rapid flow and
drainage of infiltrating water.
5-9
-------
SECTION 5
Final Cover System
The FML should be protected by an overly-
ing drainage layer of at least 30 cm (12
inches) of soil material (see Section 5 4 3).
The FML should be in direct contact with
the underlying compacted soil compo-
nent and should be installed on a
smoothed soil surface.
The number of penetrations of the FML
by designed structures (e.g., gas vents)
should be minimized. Where penetra-
tions are necessary, the FML should be
sealed securely around the structure.
5.4.3 The drainage layer should be designed to mini-
Drainage Layer mize the amount and residence time of water
coming into contact with the low-permeability
layer (infiltration layer), thereby decreasing the
potential for leachate generation. The drainage
layer construction materials and configuration
should facilitate the rapid and efficient removal of
water to an exit drain.
The drainage layer should be designed, con-
structed and operated to function without clog-
ging. Physical clogging may be prevented by
incorporating a filter layer of soil or geosynthetic
material between the top layer and the drainage
layer. The prevention of biological clogging may
range from limiting vegetation to shallow-rooted
species to the installation of a biotic barrier.
In arid locations, the need for a drainage layer
should be based on consideration of precipitation
event frequency and intensity and sorptive capac-
ity of other soil layers in the cover system. It may
be possible to construct a top layer that will ab-
sorb most, if not all, of the precipitation that infil-
5-10
-------
SECTION 5
Final Cover System
trates into that layer, eliminating the need for a
drainage layer.
If composed of granular material, such as sand,
the recommended design for a drainage layer is
as follows:
Minimum thickness of 30 cm (12 inches)
and minimum slope of 3 percent at the
bottom of the layer, greater thickness
and/or slope if necessary to provide suffi-
cient drainage flow as determined by site-
specific hydrologic modeling (e.g., HELP
model, Section 5.7).
Hydraulic conductivity of drainage mate-
rial no less than 1 x 1Cf2 cm/sec at the
time of installation.
Granular material no coarser than 3/8 inch (0.95
cm), and classified as SP; should be smooth and
rounded and should contain no debris that could
damage the underlying FML nor fines that might
lessen permeability.
A filter layer (granular or synthetic) in-
cluded between the drainage layer and top
layer, if necessary, to prevent clogging of
the drainage layer by fine particles.
If composed of geosynthetic materials, the rec-
ommended design for a drainage layer is as fol-
lows (Figure 5-3):
Same minimum flow capability as a
granular drainage layer in the same situ-
ation; hydraulic conductivity no less than
1x10" cm/sec under anticipated over-
burden for the design life.
5-11
-------
Drainage Layer Options
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low-permeability
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filter layer
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drainage layer.
vegetation/soil
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FML/soil layer
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(Source: EPA, 1989)
Figure 5-3
-------
SECTION 5
Final Cover System
Inclusion of a geosynthetic filter layer
above the drainage material to prevent
intrusion and clogging by the overlying
top layer soil material.
Inclusion of geosynthetic bedding be-
neath the drainage layer, if necessary, to
increase friction and minimize slippage
between the drainage layer and the un-
derlying FML.
5.4.4 The erosion layer typically consists of two corn-
Erosion Layer ponents: an upper vegetation component under-
lain by a soil component, usually topsoil.
The vegetation component of the erosion layer
should have the following characteristics:
Locally adapted perennial plants;
Resistance to drought and temperature
extremes;
Roots that will not disrupt the low-perme-
ability infiltration layer;
Capability of thriving in low-nutrient soil
with minimum nutrient addition;
Sufficient plant density to minimize cover
soil erosion to no more than 2
tons/acre/year, calculated using the
USDA Universal Soil Loss Equation; and
Capability of surviving and functioning
with little or no maintenance.
The lower soil component of the erosion layer
should have the following characteristics;
5-13
-------
SECTION 5
Final Cover System
A minimum thickness of 60 cm (24
inches), including at least 15 cm (6
inches) of topsoil for vegetation support;
greater total thickness where required
(e.g., where maximum frost penetration
exceeds this depth, or where greater
plant-available water storage is neces-
sary or desirable);
Medium texture to facilitate seed germi-
nation and plant root development;
Final top slope, after allowance for settling
and subsidence, of at least 3 percent, but
no greater than 5 percent, to facilitate run-
off while minimizing erosion; and
Minimum compaction to facilitate root de-
velopment and sufficient infiltration to
maintain growth through drier periods.
The thickness of the erosion layer is influenced by
depth of frost penetration and erosion potential.
Erosion can adversely affect the performance of
the final cover of a MSWLF unit by causing rills that
require maintenance and repair. As previously men-
tioned, a healthy vegetative layer can protect the
cover from erosion. Conversely, severe erosion
can affect the vegetative growth.
Extreme erosion may lead to the exposure of the
infiltration layer, initiate or contribute to sliding
failures or expose the waste. Anticipated erosion
due to surface water runoff for given design crite-
ria may be approximated using the U.S. Depart-
ment of Agriculture Universal Soil Loss Equation.
By evaluating erosion loss, the design may be
optimized to reduce maintenance through selec-
tion of the best available soil materials or by in-
5-14
-------
SECTION 5
Final Cover System
itially adding excess soil to increase the time re-
quired before maintenance is needed.
Parameters in the equation include the following:
X = RKLSCP
where:
X = Soil loss (tons/acre/year)
R = Rainfall erosion index
K = Soil erodibility index
L = Slope length factor
S = Slope gradient factor
C = Crop management factor
P = Erosion control practice
Values for the Universal Soil Loss Equation pa-
rameters may be obtained from the U.S. Soil Con-
servation Service (SCS) technical guidance
document entitled "Predicting Rainfall Erosion
Losses, Guidebook 537" (1978), available at local
SCS offices located throughout the United States.
5-4.$ Other components that may be used in the final
Optional Layers cover system include a gas vent layer and a bi-
otic layer (figures 5-4 and 5-5). These compo-
nents are discussed in the following two sections
If an FML is used as part of the final cover sys-
Gas Vent Layer tem wj|| prevent the infiltration of moisture to
the waste below and may contribute to the collec-
tion of waste decomposition gases, therefore ne-
cessitating a gas vent layer. The gas vent layer
should be at least 30 cm (12 inches) thick and
be above the waste and below the infiltration
layer. Coarse-grained porous material, similar to
that used in the drainage layer or equivalent-per-
forming synthetic material, can be used.
5-15
-------
Final Cover Design with Optional Layers
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Gas Vent Layer
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-------
SECTION 5 Final Cover System
Perforated, horizontal venting pipes should chan-
nel gases to a minimum number of vertical riser
pipes located at a high point (in the cross sec-
tion) to promote gas ventilation. To prevent clog-
ging, a granular or geotextile filter may be
needed between the venting and the low hydrau-
lic conductivity soil or geomembrane layers.
5.4.5.2 Plant roots or burrowing animals (collectively called
Biotic Layer biointruders) may disrupt the drainage and the low
hydraulic conductivity layers to interfere with the
drainage capability of the layers. A 30 cm (12
inches) biotic barrier of cobbles directly beneath the
erosion layer may stop the penetration of some
deep-rooted plants and the invasion of burrowing
animals. Most research on biotic barriers has been
done in, and is applicable to, arid areas. Geosyn-
thetic products that incorporate a time-released her-
bicide into the matrix or on the surface of the
polymer may also be used to retard plant roots.
The longevity of these products requires evaluation
if the cover system is to serve for longer than 30 to
50 years (Figures 5-6).
5.5
NATURAL FACTORS
AFFECTING FINAL
COVER
A variety of natural factors can affect the integrity
of the final cover. Among those factors are:
Settlement
Freeze-thaw effects; and
Desiccation
5.5.1 Total settlement is the total downward move-
Settlement ment of a fixed point on the surface of the cover.
Differential settlement is the difference between
the total settlements at two points of the cover.
Excessive differential settlement of underlying
5-18
-------
F'9ure 5-6
-------
SECTION 5
Final Cover System
waste can damage a cover system. If differential
settlement occurs, tensile strains develop in the
cover materials. The larger the strain, (i.e., the
stretching of the material) the greater the possibil-
ity that the soil will crack and that an FML will rup-
ture. The solution may be in waste stabilization
(e.g., deep dynamic compaction or soil preload-
ing). These technologies, however, are still
emerging.
Freeze-Thaw Effects Membrane and clay layers should be placed below
the maximum depth of frost penetration to avoid
freeze-thaw effects. Freeze-thaw effects may in-
clude development of microfractures or realign-
ment of interstitial fines, which may increase the
hydraulic conductivity of clays by more than an or-
der of magnitude. Figure 5-7 shows the regional av-
erage depth of frost penetration. However, these
values should not be used to find the maximum
depth of frost penetration for a particular site. Infor-
mation regarding the maximum depth of frost pene-
tration for a particular area can. be obtained from
the SCS, local utilities, construction companies and
local universities (Figure 5-7).
5.5.3
Desiccation Desiccation of soil liners occurs whenever the
soil liner dries, causing liner materials to crack.
If desiccation occurs in a cover system, wetting
of the soil may partly heal the desiccation
cracks. To minimize desiccation damage, the soil
layers should be kept wet during construction. A
synthetic/soil composite liner system withstands
desiccation damage to a greater degree than a
soil liner. Tests have shown that increasing the
thickness of the top layer does not prevent desic-
cation damage.
-------
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Regional Depth of Frost Penetration
(Source: EPA, 1989)
Figure 5-7
-------
SECTION 5 Final Cover System
MONITORING
5.6 Monitoring and maintaining the integrity of a final
FINAL COVER cover system as part of post-closure care is criti-
cal to ensure that the wastes are well contained
and are not releasing leachate or gases to the
environment. Periodic repairs and maintenance
may be necessary to keep the cover in good
working order. Three occurrences which should
be monitored to ensure that the final cover sys-
tem is functioning properly include:
Settlement/Subsidence
Surface Erosion
Air emissions
5.6.1 Excessive settlement and subsidence, caused
Settlement/Subsidence by decomposition and consolidation of the
wastes, can impair the integrity of the final cover
system. Evidence of settlement and subsidence
can commonly be found by walking the cover af-
ter a rain storm and looking for major puddles or
ponding. Subsidence depressions can also be
found through an annual survey of the cover us-
ing either conventional or aerial survey methods.
Subsidence depressions must be remediated be-
low the level of the barrier system to avoid poten-
tial long-term acceleration of the subsidence.
Remediation requires removing the cover system
in the region of subsidence and backfilling the de-
pression with lightweight fills. This fill may be
either more waste or commercial lightweight ag-
gregates. The full cover profile must then be re-
built over the new fill.
5-22
-------
SECTION 5
Final Cover System
5JL2
Surface Erosion
Monitoring or
Maintenance
All cover systems will erode and require long-term
maintenance. Cover systems with moderate slopes
and an agricultural cover will typically require an-
nual maintenance of 0.5 percent of their surface
area; this percentage increases with slope. Thus,
all covers that use agricultural materials require an
annual inspection and repair program. Such repair
may include cleaning out surface water swales, re-
placing cover soil and reestablishing vegetation. Ar-
eas of the cover requiring repeated repair may
benefit from the use of geosynthetic erosion control
blankets, or materials such as broken rock or cob-
bles in lieu of vegetation.'
The annual inspection should verify that the agri-
cultural cover is being mowed at least annually
to prevent the growth of deep-rooted volunteer
vegetation. In arid regions of the country or dur-
ing droughts, landfill covers may not be able to
maintain vegetation unless the plants are very
drought-resistant. This loss of vegetation is due
to moisture loss in the root zone of the cover
soil, resulting from characteristics of the underly-
ing drainage system.
5.6.3 Air emissions from waste storage facilities will
Air Emissions come under increasing scrutiny in the next dec-
ade. Monitoring techniques will be similar to
those used at industrial facilities and include pas-
sive sample vessels, and active pump and filter
samples. The most common air contaminants
coming from the waste disposal cell obviously
are waste-dependent; for MSWLF wastes, these
contaminants of concern are methane, vinyl chlo-
ride and benzene. Figure 5-8 presents typical al-
lowable limits of selected air contaminants.
Such limits are currently undergoing extensive re-
view; significantly lower allowable levels are an-
ticipated for future operations.
5-23
-------
V
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-------
SECTION 5
Final Cover System
5.7 HELP is a computer-based mathematical water-
HELP MODEL budget model that performs daily sequential
analyses to generate daily, monthly and annual
estimates of runoff, evapotranspiration, lateral
drainage, leakage through covers, leachate col-
lection, leachate detection and leakage through
clay liners and FMLs. The HELP model was de-
veloped at the U.S. Army Corps of Engineers
(USACE) Waterways Experiment Station for the
EPA Office of Solid Waste to provide technical
support for the RCRA and Superfund programs.
It provides permit evaluators and landfill design-
ers with a tool to rapidly evaluate and compare
the performance of alternate landfill designs by
simulating various hydrologic processes within
the landfill environment and evaluating the integ-
rity and performance of the unit.
The model is available to operators and regula-
tors free of charge from the USACE Waterways
Experiment Station in Vicksburg, Mississippi.
The input parameters of the model vary with the
process being modeled (see Figure 5-9). Typical
input parameters include
Rainfall and Climatological Data
Soil Type and Properties
Cover Vegetation Type
Landfill Design Features
5-25
-------
Typical Output Data
Daily Values (Optional)
Monthly Totals and Other Values (Optional)
Annual Totals and Other Values
Averages and Standard Deviations of Monthly and
Annual Totals
Peak Daily Values for Simulation Period
-------
SECTION 5
Final Cover System
References
1. U.S. Environmental Protection Agency, Design and Construction of RCRA/CER-
CLA Final Covers. EPA/625/4-91/025 (Cincinnati, OH: GPO, 1991).
2. U.S. Environmental Protection Agency, Design and Construction of
RCRA/CERCLA Final Covers. CERI 90-50 (Washington, DC: GPO, 1990)
3. Robert Koerner, Designing with Geosvnthetics.
4. Teressa Austin, "Landfill-Cover Conflict" Civil Engineering (NY: American
Society of Civil Engineers, December 1992).
5. U.S. Environmental Protection Agency, Requirements for Hazardous
Waste Landfill Design. Construction, and Closure. EPA/625/4-89/022 (Cin-
cinnati, OH: GPO, 1989).
6. U.S. Environmental Protection Agency, Seminars - Design. Operation and
Closure of Municipal Solid Waste Landfills. EPA/600/K-92/002 (April 1992).
7. U.S. Environmental Protection Agency, Solid Waste Disposal Facility Cri-
teria. Technical Manual, EPA 530-R-93-017 (November 1993).
8. U.S. Environmental Protection Agency, Covers for Uncontrolled Hazard-
ous Waste Sites, EPA/540/2-85/002 (September 1985).
9. SCS Engineers, Virginia Landfill Training Manual, prepared under EPA
Contract No. 68-WO-025, WA No. 253 for Science Applications Interna-
tional Corporation, SAIC Project No. 01-26-03-2753-000 (May 1993).
10. U.S. Environmental Protection Agency, Technical Guidance Document: Fi-
nal Covers on Hazardous Waste Landfills and Surface Impoundments.
EPA/530-SW-89-047 (July 1989).
11. U.S. Environmental Protection Agency, Guide to Technical Resources for the
Design of Land Disposal Facilities. EPA/625/6-88/018 (December 1988).
5-27
-------
SECTION 5
Final Cover System
5-28
-------
-------
SECTION 6.0
Groundwater Monitoring
Page No.
6.1 INTRODUCTION 6-1
6.2 APPLICABILITY 6-1
6.3 MSWLF GROUNDWATER MONITORING PROGRAMS 6-2
6.3.1 Detection Monitoring Program 6-2
6.3.2 Assessment Monitoring Program 6-5
6.4 GROUNDWATER MONITORING SYSTEMS 6-8
6.4.1 Requirements for Groundwater Monitoring Systems 6-8
6.4.2 Monitoring Well Performance Standards 6-10
6.4.3 Groundwater Monitoring System Design Considerations 6-11
6.4.4 Monitoring Well Design 6-11
6.4.4.1 Borehole 6-13
6.4.4.2 Well Casing 6-14
6.4.4.3 Sump or Sediment Trap 6-19
6.4.4.4 Well Intake (Screen) 6-19
6.4.4.5Filter Packs 6-21
6.4.4.5.1 Natural Filter Packs 6-23
-------
6.4.4.5.3 Filter Pack Placement 6-24
6.4.4.6 Filter Pack And Well Screen Design 6-27
6.4.4.7 Annular Seals 6-28
6.4.4.7.1 Filter Pack Seal (Bentonite Pellet Seal or
Plug) 6-29
6.4.4.7.2Annular Grout Seal 6-29
6.4.4.7.3 Bentonite 6-30
6.4.4.7.4 Cement 6-30
6.4.4.8 Surface Seal and Completion 6-32
6.4.4.8.1 Above Grade Completion 6-31
6.4.4.8.2 Flush Completion 6-32
6.4.5 Construction Methods 6-32
6.4.5.1 Drilling Techniques 6-33
6.4.5.1.1 Auger Drilling Methods 6-35
6.4.5.1.1.1 Solid-Stem Auger 6-35
6.4.5.1.1.2 Hollow-Stem Auger 6-38
6.4.5.1.2 Rotary Drilling Methods 6-45
6.4.5.1.2.1 Rotary Wash Drilling 6-45
6.4.5.1.2.2 Air Rotary Drilling 6-49
6.4.5.1.2.3 Mud Rotary Drilling 6-50
6.4.5.1.3 Other Drilling Methods 6-50
-------
6.4.5.1.4 Cleaning and Decontamination 6-50
6.4.5.2 Monitoring Well Development 6-50
6.4.5.2.1 Bailing 6-54
6.4.5.2.2 Surging 6-54
6.4.5.2.3 Pumping/Overpumping/Backwashing . . 6-56
6.4.5.2.4 Air Lift 6-56
6.4.5.3 Well Construction Documentation 6-57
6.4.5.4 Well Abandonment 6-58
6.4.6 Placement of Monitoring Wells 6-58
6.4.6.1 Hydrogeologic Characterization 6-60
6.4.6.1.1 Existing Information 6-60
6.4.6.1.2 Site-Specific Hydrogeologic Investigation 6-62
6.4.6.2 Field Observations 6-64
6.4.6.3 Drilling and Materials Testing Programs 6-64
6.4.6.3.1 Boreholes 6-65
6.4.6.3.2 Piezometers 6-65
6.4.6.3.3 Monitoring Wells 6-65
6.4.6.3.4 Materials Testing 6-65
6.4.6.4 Other Characterization Techniques 6-67
6.4.6.4.1 Data Presentation, Interpretation and
Evaluation 6-67
-------
6.4.6.4.2 Site Location Maps 6-69
6.4.6.4.3 Stratigraphic Cross-Sections and Fence
Diagrams 6-69
6.4.6.4.4 Data Tables and Graphs 6-69
6.4.6.4.5 Potentiometric Maps and Flow Nets . . . 6-74
6.4.6.4.6, Narrative Description of Hydrogeology . 6-78
6.4.6.4.7 Other Information 6-78
6.4.6.5 Well Location Selection 6-79
6.4.6.6 Groundwater Velocity and Dispersivity 6-80
6.4.6.7 Mounding Effects and Groundwater Reversals 6-85
6.4.6.8 Examples of Monitoring Well Siting Scenarios 6-85
6.5 GROUNDWATER SAMPLING AND ANALYTICAL REQUIREMENTS .. 6-100
6.5.1 Sample Collection 6-100
6.5.1.1 Groundwater Level Measurement 6-103
6.5.1.1.1 Electric Water Levellndicators 6-105
6.5.1.1.2 Acoustic Water Level Indicators 6-105
6.5.1.1.3 Popper or Bell Sounder 6-105
6.5.1.1.4 Weighted Tape 6-105
6.5.1.1.5 Chalked Tape 6-105
6.5.1.1.6 Other Methods 6-107
6.5.1.2 Purging 6-107
-------
6.5.1.3 Sampling Equipment Decontamination 6-107
6.5.1.4 Sampling Procedures 6-109
6.5.1.5 Filtering 6-109
6.5.2 Sample Preservation and Shipment 6-113
6.5.3 Chain-of-Custody 6-114
6.5.4 Analytical Procedures 6-115
6.5.5 Quality Assurance/Quality Control 6-115
6.5.6 Statistical Evaluations 6-117
6.5.6.1 Parametric ANOVA 6-119
6.5.6.2 ANOVA Based on Ranks 6-119
6.5.6.3 Tolerance or Prediction Intervals 6-119
6.5.6.4 Control Chart 6-120
6.5.6.5 Other Statistical Methods 6-120
6.5.7 Groundwater Protection Standards 6-120
6.6 CONTAMINANT FATE AND TRANSPORT PROCESSES 6-120
6.6.1 Physical Processes 6-121
6.6.1.1 Advection 6-121
6.6.1.2 Dispersion 6-121
6.6.1.3 Diffusion 6-124
6.6.1.4 Retardation 6-124
6.6.2 Chemical Processes 6-124
-------
6.6.2.1 Sorption 6-125
6.6.2.2 Dissolution/Precipitation 6-125
6.6.2.3 Acid-Base Reactions 6-125
6.6.2.4 Complexation 6-125
6.6.2.5 Hydrolysis/Substitution 6-126
6.6.2.6 Redox Reactions 6-126
6.6.2.7 Radioactive Decay 6-126
6.6.3 Biological Processes 6-126
6.6.4 Nonaqueous-Phase Liquids 6-127
6.6.4.1 Light Nonaqueous-Phase Liquids 6-127
6.6.4.2 Dense Nonaqueous-Phase Liquids 6-130
6.6.5 Delineation of Extent of Contamination/Additional Monitoring 6-132
REFERENCES 6-133
List of Figures Page No.
6-1 Flow Chart of Detection Monitoring Program 6-3
6-2 Flow Chart of Assessment Monitoring Program 6-6
6-3 Comparison of Single Unit and Multiunit Monitoring Systems . 6-9
6-4 Diagram of Typical Monitoring Well Construction 6-12
6-5 Forces Exerted on Monitoring Well Materials 6-16
6-6 Types of Well Casing Joints 6-18
-------
6-7 Types of Well Intakes (Screens) 6-20
6-8 Envelope of Coarse-Grained Material Around
Well Screen (Filter Pack) 6-22
6-9 Tremie Pipe Emplacement of Artificial Filter Pack Materials . 6-25
6-10 Free Fall Method of Filter Pack Emplacement With
a Hollow-Stem Auger 6-26
6-11 Drilling Methods for Various Types of Geologic Settings . . . 6-34
6-12 Diagram of a Solid-Stem Auger 6-36
6-13 Applications and Limitations of Solid-Stem Augers 6-37
6-14 Diagram of a Hollow-Stem Auger 6-39
6-15 Applications and Limitations of Hollow-Stem Augers 6-40
6-16 Sequential Steps in Hollow-Stem Drilling and Sampling .... 6-41
6-17 Flexible Center Plug in Hollow-Stem Auger Bit 6-42
6-18 Hollow-Stem Auger With Pilot-Bit Assembly 6-43
6-19 Hollow-Stem Auger With Knock-Out Bottom Plug 6-44
6-20 Diagram of a Direct Rotary Drilling System 6-46
6-21 Applications and Limitations of Direct Mud Rotary Drilling . . 6-47
6-22 Applications and Limitations of Air Rotary Drilling 6-48
6-23 Diagram of a Cable Tool Drilling System 6-51
6-24 Applications and Limitations of Cable Tool Drilling 6-52
6-25 Diagram of a Typical Surge Block 6-55
-------
6-26 Factors Influencing the Density of Borholes 6-66
6-27 Summary of Hydrogeologic Investigation Techniques 6-68
6-28a, b Summary of Other Data Presentation and Interpretation
Techniques 6-70 and 6-71
6-29 Simple Geologic Cross-section 6-72
6-30 Typical Fence Diagram 6-73
6-31 Typical Potentiometric Map 6-75
6-32 Interpolating Potentiometric Data 6-76
6-33 Typical Flow Net 6-77
6-34 Factors Influencing Well Spacing 6-81
6-35 Factors Influencing Number of Wells per Location 6-82
6-36 Contaminant Migration in High and Low Velocity Groundwater
Settings 6-83
6-37 Contaminant Migration in High and Low Transverse Dispersivity
Settings 6-84
6-38 Mounding Effects on Contamiant Migration 6-86
6-39 Monitoring System for Simple Geologic Setting 6-87
6-40 Monitoring System for Complex Geologic Setting 6-88
6-41 Monitoring System for Karst Geology 6-89
6-42 Contaminant Migration-Scenario 1 6-90
6-43 Contaminant Migration-Scenario 2 6-91
-------
6-44 Contaminant Migration-Scenario 3 6-92
6-45 Contaminant Migration-Scenario 4 6-93
6-46 Contaminant Migration-Scenario 5 6-94
6-47 Contaminant Migration-Scenario 6 6-95
6-48 Contaminant Migration-Scenario 7 6-96
6-49 Contaminant Migrgtion-Scenario 8 6-97
6-50 Contaminant Migration-Scenario 8 (Surface View) 6-98
6-51 Contaminant Migration-Scenario 9 6-99
6-52 Generalized Flow Diagram of Groundwater Sampling Steps 6-102
6-53 Typical Electric Water Level Indicator 6-106
6-54 Typical Sampling Bailer 6-110
6-55 Typical Bladder Pump 6-111
6-56 Typical Vaccum Bottle Sample Collection Method 6-112
6-57 Aqueous Phase Contaminant Fate and Transport Process . . 6-122
6-58 Dispersion in a Porous Media 6-123
6-59 Non Aqueous Phase Liquids 6-128
6-60 Movement of LNAPLs into the Subsurface 6-129
6-61 Movement of DNAPLs into the Subsurface 6-131
-------
SECTION 6
Goundwater Monitoring
INTRODUCTION
APPLICABILITY
The Subtitle D regulations require implementa-
tion of a routine groundwater monitoring program
to assess the effectiveness of the MSWLF's con-
tainment of wastes. Waste constituents can be
released to groundwater if not adequately con-
tained by the landfill design components.
This section summarizes the groundwater monitor-
ing requirements as defined in Subpart E of the
Subtitle D regulations and discusses the compo-
nents of an effective groundwater monitoring
program.
Subpart E of the Subtitle D regulations require
that groundwater monitoring be performed at
All new MSWLFs which began receiving
waste after the effective date.
Existing MSWLFs which received waste
prior to the effective date and continued
to receive waste after the effective date.
Lateral expansions of existing MSWLFs.
Once established at a MSWLF, groundwater
monitoring must continue throughout the facility's
active life and post-closure care period.
A MSWLF may be granted an exemption from
the groundwater monitoring requirements in
EPA=approvecLstale.programs if it can be demon-
strated that there is no potential for hazardous
constituents to migrate from the MSWLF to the
uppermost aquifer.
6-1
-------
SECTION 6
Groundwater Monitoring
6,3
MSWLF
GROUNDWATER
MONITORING
PROGRAMS
6.3.1
Detection Monitoring
Program
Suspending groundwater monitoring
where it can be demonstrated that there is
no potential for migration of hazardous con-
stituents from the MSWLF unit to the up-
permost aquifer.
Identifying an alternative (shorter) list of
detection monitoring parameters if it can
be shown that any deleted constituents
are not expected to be contained in or de-
rived from the waste.
Designating an alternative frequency for
detection monitoring. The alternative
monitoring frequency must be no less
than annual.
6-2 RCRA Subtitle D Technical Training Manual
Two types of monitoring programs have been es-
tablished to assess groundwater quality at
MSWLFs:
Detection Monitoring Program
Assessment Monitoring Program
Groundwater detection monitoring is required at
all MSWLFs subject to the Subtitle D regulations
and must be performed at all monitoring wells
(Figure 6-1).
A detection monitoring program must be estab-
lished that includes semiannual monitoring for
the Appendix I constituents at background and
point of compliance locations. EPA-approved
-------
Flow Chart of Detection Monitoring
Program
Figure 6-1
-------
SECTION 6
Groundwater Monitoring
Designating an alternative distance for lo-
cating point of compliance monitoring
wells. The alternative point of compli-
ance distance must be no greater than
150 meters from the waste management
unit boundary.
Within a reasonable period of time after complet-
ing each sampling and analysis, the groundwater
monitoring data must be evaluated to determine
whether there is a statistically significant in-
crease over background values for any of the
detection monitoring constituents.
In order to perform the statistical evaluations,
background groundwater quality must be estab-
lished for each of the monitoring constituents.
Background groundwater quality data may be de-
rived from locations that are either hydraulically
upgradient from the MSWLF unit or at other loca-
tions that provide more representative
background data.
Groundwater data collected from the point of com-
pliance (detection monitoring wells) must be
compared against the background data to deter-
mine if there is an SSI at any of the compliance
monitoring wells. Within 14 days of determining
that an SSI of one or more detection monitoring
constituents has occurred, the state regulatory
authority must be notified that the results have
been placed in the operating record. An assess-
ment-monitoring program must be implemented
within 90 days, unless it can be demonstrated that
another source caused the contamination or that
the SSI resulted from errors in sampling, analysis,
statistical evaluation or natural variation in ground-
water quality.
6-4
-------
SECTION 6
Goundwater Monitoring
6.3.2
Assessment Monitoring
Program
A flow chart of the detection monitoring program
is presented in Figure 6-1.
Assessment monitoring is required whenever a
SSI over background has been detected for one
or more of the detection monitoring constituents
(Figure 6-2). The assessment monitoring pro-
gram requires that:
Within 90 days of triggering the assess-
ment monitoring program, and annually
thereafter, groundwater must be ana-
lyzed for all of the Appendix II constitu-
ents. For any constituent detected in the
downgradient wells as the result of the
complete Appendix II analysis, a suffi-
cient number of independent samples
must be collected and analyzed for each
well (background and downgradient) to
establish background and provide for sta-
tistical evaluation of the detected con-
stituents. Within 14 days after obtaining
the analytical results the state regulatory
authority must be notified that informa-
tion on the Appendix II constituents that
have been detected has been placed in
the operating record.
Within 90 days, and at least semiannu-
ally thereafter, groundwater must be re-
sampled for the detection monitoring
parameters (Appendix I or alternative
Jisi) and for-detectedJ\ppendix II constitu-
ents.
Groundwater protection standards must
also be established for all detected Ap-
pendix II constituents.
6-5
-------
Flow Chart of Assessment Monitoring
Program
Ok
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-------
SECTION 6
Goundwater Monitoring
Statistical evaluations must be conducted to de-
termine if the detected constituents are above
background and above or below the groundwa-
ter protection standards. If the concentrations of
Appendix II constituents are at or below back-
ground values for two consecutive sampling
events, the state program may allow the MSWLF
to return to detection monitoring; if above back-
ground values, but below the groundwater
protection standard, then the MSWLF must con-
tinue assessment monitoring; if above the
groundwater protection standard, the MSWLF
must notify the State regulatory agency and all
appropriate local government officials within 14
days that the information about Appendix II con-
stituents which have exceeded the groundwater
protection standard has been placed in the oper-
ating record. Additional assessment
monitoring program activities must also be un-
dertaken which include the following:
Characterizing the nature and extent of
the release.
Installing and sampling at least one addi-
tional monitoring well located at the facil-
ity boundary in the direction of
contaminant migration.
Installing and sampling other monitoring
wells as necessary.
Notifying all persons who own or reside
ฆGf> land-that directly overlies any part of
a groundwater contamination plume that
has migrated offsite.
Initiating an assessment of corrective
measures within 90 days or demonstrat-
6-7
-------
SECTION 6 Groundwater Monitoring
ing that another source caused the con-
tamination or that the SSI resulted from
error in sampling, analysis, statistical
evaluation or natural variation in ground-
water quality.
The MSWLF is required to continue assessment
monitoring through the duration of the corrective
action period or until otherwise directed by the
appropriate regulatory authority.
A flow chart of the assessment monitoring pro-
gram is presented in Figure 6-2.
6.4
GROUNDWATER
MONITORING
SYSTEMS
Groundwater monitoring system must be in-
stalled at each MSWLF unit that is subject to
the Subtitle D regulations.
EPA-approved state programs may allow for instal-
lation of a multiunit groundwater monitoring system
if the MSWLF consists of more than one MSWLF
unit. Multiunit groundwater monitoring systems
must meet the same objectives and requirements
as individual monitoring systems and be at least as
protective to human health and the environment as
individual systems. A schematic comparison of sin-
gle unit and multiunit monitoring systems is
presented in Figure 6-3.
6.4.1 The groundwater monitoring system must yield
Requirements for from the uppermost aquifer samples that
Groundwater Monitoring
Systems
Represent background groundwater qual-
ity that has not been affected by leakage
from the MSWLF unit.
6-8
-------
Comparison of Single Unit and Multiunit
Monitoring
\
Groundwater
Flow
gj, ,
! f
Bh0-
"55
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Single Unit
\
Groundwater
Flow
0
65 B
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Multiunit
Figure 6-3
-------
SECTION 6
Groundwater Monitoring
6.4.2
Monitoring Well
Performance Standards
Represent the quality of groundwater
passing the relevant point of compliance
(the waste management unit boundary or
an alternative distance up to 150 meters,
if allowed in EPA-approved state pro-
grams).
In order to meet the above-mentioned objec-
tives, the groundwater monitoring system must
include a sufficient number of wells which have
been:
Installed at appropriate locations
Installed to monitor appropriate depth inter-
vals
The monitoring wells must be constructed in a
manner that achieves the following minimum per-
formance standards.
Cased to maintain the structural integrity
of the well and borehole;
Screened and packed with an appropri-
ate filter material (e.g., sand or gravel) to
facilitate the collection of representative
groundwater samples; and:
Sealed to prevent surface water infiltration
and contamination of samples and ground-
water.
Additional monitoring well construction require-
ments include:
Notification of the state regulatory author-
ity that monitoring well design and instal-
6-10
-------
SECTION 6
Goundwater Monitoring
lation details have been included in the
MSWLF operating record.
Well installation and decommissioning in
compliance with additional state regula-
tions regarding construction, registra-
tions and abandonment.
6.4.3 The essential considerations for designing
Groundwater Monitoring groundwater monitoring systems are:
System Design
Considerations
Monitoring well design
Construction methods
Monitoring well placement
6.4.4 When properly designed and installed, the compo-
Monitoring Well Design nents of a monitoring well allow for the collection of
an adequate volume of water from the desired
water-bearing formation. A diagram of a typical
monitoring well is presented in Figure 6-4. The
monitoring well components include the following:
Borehole
Well casing
Sump or sediment trap
Well intake (screen)
Filter pack
Annular seals
Surface seal and completion
6-11
-------
Diagram of a Typical Monitoring Well
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CONTINUOUS POUR CONCRETE CAP
AND WELL APRON
CEMENT AND SODIUM
BENTONITE GROUT
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s s =
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SEE
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[fits: 1
-BENTONITE SEAL
(2 FEET)
i FILTER PACK
(2 FEET ABOVE SCREENI
V
POTENTIOMETRIC SURFACE
- SCREENED INTERVAL
ZONE OF
Figure 6-4
-------
SECTION 6
Goundwater Monitoring
A primary concern when selecting well construc-
tion materials is the use of materials that will not
compromise the integrity of the well and any fu-
ture analytical data. Another concern is to select
materials that will be rugged enough to endure
the entire monitoring period. Site conditions will
generally dictate the type of materials that can
be used.
6.4.4.1 The borehole is the open hole in the formation
Borehole that is constructed during the drilling process.
Borehole diameter is dependent upon the diame-
ter of the monitoring well materials and the
drilling technique employed. The borehole
should be of sufficient diameter so that well con-
struction and placement of the filter pack and
annular seal materials can proceed without ma-
jor difficulties. A minimum 2-inch annular space,
between the casing and the borehole wall, is nec-
essary to ensure placement of acceptable
thicknesses of filter pack, bentonite pellet seal
and the annular grout seal.
For example, if the inside diameter (ID) of the
casing is 4 inches, and the wall thickness is ap-
proximately a quarter inch, then the borehole will
have to be 8.5 inches to provide a 2-inch annular
space between the outside diameter (OD) of the
casing (4-inch ID plus twice the casing wall thick-
ness) and the borehole wall.
The 2-inch annular space will also provide room
for the use of tremie pipes at a diameter up to
-1 .-Cnnehes-for-placing the^filter-pack, bentonite
pellet seal and annular grout seal. Larger annu-
lar spaces may be necessary depending upon
drilling method, formation materials and depth of
materials placement. Sometimes it is necessary
to overdrill the borehole so that any soils that
6-13
-------
SECTION 6
Groundwater Monitoring
have not been removed, or may collapse into the
borehole during auger or drill stem retrieval, will
fall to the bottom of the borehole below the depth
where the well intake (screen and filter pack) will
be placed. The borehole can also be overdrilled
to allow for placement of a sump or sediment
trap in the well below the well screen.
If the borehole is overdrilled too much, it can be
backfilled to the designed depth with bentonite
pellets or, in some instances, the filter sand that
is to be used for the filter pack.
6.4.4.2 The well casing is the rigid tubular material placed
Well Casing into the borehole to provide access from the sur-
face of the ground to the well intake and to
maintain the borehole's integrity. Casing diameter
depends upon the purpose of the well and is se-
lected to accommodate the down hole equipment
(i.e., pumps, logging tools, samplers) that will be
employed.
Casing diameter selection criteria include the following:
Drilling or well installation method
Depth of well installation
Hydraulic characteristics of monitored
zone
Ease and extent of well development
...... . Reeled pufge volume prior to sampling
Well recovery rates after development
and/or purging
Aquifer testing requirements
6-14
-------
SECTION 6
Goundwater Monitoring
Cost
Most monitoring wells are constructed with 2- or 4-
inch ID casings. The casing material must be rug-
ged to withstand long-term monitoring activities
and should be selected after consideration of the
following site-specific factors:
Geological environment
Geochemical environment (natural
and contaminants)
Design life of monitoring well
Ease in handling
Anticipated well depth
Forces exerted on monitoring well components
which must be considered when selecting materi-
als are presented in Figure 6-5.
Well casing and screens are available in a vari-
ety of materials including:
Thermoplastic materials
Polyvinyl chloride (PVC) (not recom-
mended in the presence of some or
ganic compounds due to sorption and
leaching properties)
Acrylonitrile butadiene styrene (ABS)
Metallic materials
- Carbon steel
6-15
-------
Forces Exerted on Monitoring Well
Materials
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8
21
3'
3'
3
C
0)
Borehole
Casing joint
Compressive forces ฆ
ฆ Casing
Tensile (pull-apait) forces
critical at casing Joints
Collapse forces
(critical at greater depths)
Well intake (screen)
Compressive
strength
III
(Source: EPA, 1989)
S Collapse
^ strength
Figure 6-5
-------
SECTION 6
Goundwater Monitoring
- Stainless steel (304 and 316)
Fluoropolymer materials
- Polytetrafluoroethylene (PTFE)
- Tetrafluoroethylene (TFE)
- Fluorinated ethylene propylene (FEP)
- Perfluoralkoxy (PFA)
Polyvinylidene fluoride (PVDF).
Fiberglass
PVC and stainless steel are the two most com-
monly used construction materials for monitoring
wells. Other materials used for construction of
wells for purposes other than monitoring may not
be appropriate for use in long-term monitoring
programs because of their low resistance to
chemical attack and potential impacts on ground-
water samples.
Well materials come in sections which must be
joined during construction (Figure 6-6.) The pre-
ferred joining method for monitoring wells is with
flush-threaded connections. Flush-threaded ma-
terials are completed with male and female
threaded ends which when screwed together
form a joint which is uniform on both the inner
and outer sides. Welded or solvent-glued joints
carumpact groundwater, quality..and should not
be used for monitoring wells.
A plug or cap, constructed of the same material
as the casing, is placed at the bottom of the well
string (casing and screen) to prevent the filter
6-17
-------
Types of Well Casing Joints
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Note: Not used for
monitoring wells.
(Source: EPA, 1989)
a FluSh-)oint eating
(joined by solvent welding)
b Threaded, flush-joint casing
(joined by threading casing together)
C Plain square-end casing
(joined by solvent welding
with couplings)
d Threaded casing
(joined by threaded couplings)
e Bell-end casing
(joined by solvent welding)
I Plam squa
-------
SECTION 6
Goundwater Monitoring
pack and unconsolidated materials at the bottom
of the borehole from creeping up into the well.
6.4.4.3 Sumps or sediment traps serve as catch basins
Sump or Sediment Trap or storage areas for sediments that flow into the
well and drop out of suspension. A sump usually
consists of a 2- to 10-foot section of well casing
located below the well screen. Sumps are added
to the well screens when the wells are screened
in aquifers that are naturally turbid and will not
yield clear formation water (free of visible sedi-
ment) even after extensive development. The
sediment can then be periodically pumped out of
the sump, preventing the well screen from be-
coming "silted up."
6.4.4.4 The well intake is a slotted or perforated section
Well Intake (Screen) of the casing that permits groundwater to flow
into the well (Figure 6-7). The well intake is de-
signed in conjunction with the filter pack to
maximize groundwater inflow and minimize the
inflow of suspended solids from the formation.
Continuous wire wrap or machine-slotted well in-
takes (screens) are typically used for monitoring
wells. (Perforated well intakes are more common
in water supply applications.) Monitoring well in-
take design factors include
Corrosion and chemical resistance
Screen length
Screen type
Screen opening size (slot size)
Screen slot size selection is dependent upon
6-19
-------
Types of Well Intakes (Screens)
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3"
-------
SECTION 6
Goundwater Monitoring
The grain size of the formation materials in
wells constructed with natural (formation)
filter packs; or:
The grain size selected for the artifi-
cial filter pack.
Typical screen slot widths used for monitoring
wells range in size from 0.006 inch to 0.030 inch.
The most common slot width for PVC materials
used in formations with an abundance of fines is
0.010 inch.
Well screen length depends upon the thickness
of the monitoring interval. Shorter screen inter-
vals provide information concerning a specific
section of the formation, whereas larger screen
intervals are best used to monitor the presence
of gross contamination in the aquifer. The length
of well screens in permanent monitoring wells
should be great enough to effectively monitor the
interval, or zone of interest, during water level
fluctuations. Well screens designed for long-term
monitoring purposes are normally not less than 5
feet in length and rarely exceed 20 feet. The
most commonly used screen length is 10 feet.
6.4.4.5 Filter packs (Figure 6-8) are composed of granu-
Filter Packs lar materials placed around the well intake
(screen). They restrict the movement of forma-
tion-fine materials (silt and clay particles) into the
well while permitting groundwater to enter the
well.-The-filter-pack-material -should consist of
clean, well-rounded to rounded particles of sili-
ceous composition. The grain-size distribution,
or particle sizes, of the filter pack materials
should be selected to retain 90 percent of the for-
mation materials. Two types of filter packs are
6-21
-------
Envelope of Coarse-Grained Material
Around Well Screen (Filter Pack)
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Figure 6-8
-------
SECTION 6
Goundwater Monitoring
typically utilized in unconsolidated, or poorly-con-
solidated materials: natural and artificial.
6.4.4.5.1
Natural filter packs
Natural filter packs are constructed by allowing
the surrounding formation to collapse around the
well intake. The well is then developed (pumped)
in a manner that creates an envelope of coarser-
grained materials around the intake. In wells with
natural filter packs, the diameter of the well cas-
ing and well intake is selected to closely
approximate the diameter of the borehole, and
the well intake is designed in association with
the grain size of the formation. Natural filter pack
wells are most commonly installed in permeable,
coarse-grained formations.
6.4.4.5.2
Artificial filter packs
Artificial filter packs are constructed by placing
coarser, permeable materials (typically sand) in
the annular space between the well intake and
the natural formation.
Artificial filter packs serve several purposes:
Filter fine-grained materials
Stabilize the borehole
Minimize settlement of materials above
the well intake
Increase the effective diameter of the well
Increase the amount of water flowing into
-thewell
Artificial filter packs generally allow the slot size
to be considerably larger than if screened in the
natural formation. Design factors for an artificial
filter pack include
6-23
-------
SECTION 6
Groundwater Monitoring
6.4.4.5.3
Filter Pack Placement
Grain size distribution of formation
Filter pack grain size
Intake opening (slot size)
Intake length
Filter pack length
Filter pack thickness
Filter pack material
An artificial filter pack should extend from the bot-
tom of the well intake to approximately 2 to 5 feet
above the top of the well intake. The thickness of
the filter pack should be at least 2 to 4 inches.
Filter pack materials must be chemically inert to
preserve the natural chemistry of the groundwa-
ter. The material should be well-rounded to
enhance permeability and should contain less
than 5 percent nonsiliceous material. The most
commonly used filter pack material is clean quartz
sand.
Filter pack material should be placed into the
borehole under the bottom of the well screen to
provide a firm footing and to filter flow beneath
the screened interval. The filter pack should also
extend a minimum of 2 feet above the top of the
well screen. Filter pack should be placed by the
irerme or-positive displacement method (Figure 6-
9) in deep wells and when using rotary wash
drilling methods.
Placing the filter pack by "pouring" (Figure 6-10)
may be acceptable in certain situations (i.e., at
6-24
-------
Tremie Pipe Emplacement of Artificial
Filter Pack Materials
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Figure 6-9
-------
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2
8
3'
-------
SECTION 6
Goundwater Monitoring
shallow depths and when accomplishing installa-
tion through hollow-stem augers).
6.4.4.6 The majority of monitoring wells are installed in
Filter Pack And Well shallow water-bearing units that consist of silts,
Screen Design clays and sands in various combinations. These
shallow water-bearing units are not generally
characteristic of sand aquifers used for drinking
water. The relatively high silt and clay content
often make it difficult to design wells that yield
low turbidity water. Selection of well screen slot
size and filter pack grain size is often controlled
by manufacturing capabilities and not technical
design factors. In these instances the filter pack
material is selected based upon the smallest
screen slot width available (i.e., 0.010 machine-
slotted PVC) and the best available appropriately
graded silica sand.
Ideally, the filter pack and well screen design
should be based on the results of a sieve analy-
sis conducted on soil samples collected from the
aquifer or the formation(s) that will be monitored.
The data from the sieve analysis are plotted on a
grain-size distribution graph, and a grain-size dis-
tribution curve is generated. The uniformity
coefficient (Cu) of the aquifer material is deter-
mined from the grain-size distribution curve. The
Cu is the ratio of the 60 percent finer material
(D60) to the 10 percent finer material (D10)
The Cu ratio is a way of grading or rating the uni-
formity of grain size. For example, a Cu of unity
means that the individual grain sizes of the mate-
rial are nearly all the same, while a Cu with a
6-27
-------
SECTION 6
Groundwater Monitoring
large number means a large range of sizes. As a
general rule, a Cu of 2.5 or less should be used
in designing the filter pack and well screen.
6.4.4.7 There are two types of seals installed in the annu-
Annular Seals lar space above the filter pack: filter pack seal
(bentonite pellet seal or plug) and annular grout
seal.
The purpose of the annular seals are to:
Protect the chemical integrity of the filter
pack
Eliminate infiltration of surface water
Prohibit vertical migration of groundwater
between water-bearing zones
Seal discrete sampling zones
Annular seal materials must comply with the fol-
lowing design requirements:
Allow for installation from ground surface.
Hydrate or set within a reasonable period
of time.
Provide a positive seal between the cas-
ing and formation.
Bei^iemicallyinert.
Be resistant to physical or chemical deterio-
ration.
Be impermeable to fluids.
6-28
-------
SECTION 6
Goundwater Monitoring
The annular seal materials most commonly used
for monitoring well construction are bentonite
and cement.
6.4.4.7.1 A seal consisting of a high solids, pure bentonite
Filter pack seal (bentonite material or other inert materials must be placed
pellet seal or plug) on top of the filter pack to prevent infiltration of
the cement grout into the screened well interval.
The bentonite seal should be a minimum of 2
feet in thickness.
Bentonite pellets or bentonite slurries are com-
monly used to form the filter pack seal
depending upon the depth of placement, method
of placement and thickness of seal required. The
preferred method of placing bentonite slurries
and/or pellets is by the tremie method (or
through the hollow-stem augers for pellets.)
Placement by these methods minimizes the risk
of bridging in the borehole and ensures place-
ment of the bentonite seal at the proper interval.
Pouring the bentonite pellets directly into the
borehole can be performed in shallow boreholes
(generally less than 50 feet) where the annular
space is large enough to prevent bridging. The
bentonite pellet seals should be measured with a
tape to ensure placement at the proper intervals.
The bentonite pellets must be hydrated either by
placement in the formation water or by adding
potable water, if placed above the water table.
6.4.4.7.2 The annular space between the casing and the
Annular grout seal borehole-welf-must-be-sealed-above the ben-
tonite filter pack seal to within approximately 2
feet of the ground surface (or below the frost
line, whichever is deeper). Annular grout seals
may consist of: high solids, pure bentonite grout,
a neat cement grout or a cement/bentonite grout.
6-29
-------
SECTION 6
Groundwater Monitoring
6.4.4.7.3 Bentonite is a hydrous aluminum silicate clay
Bentonite that, when mixed with water, typically expands
10 to 15 times its dry volume. Bentonite quickly
forms an extremely dense, low-permeability clay
mass that provides a tight seal between the cas-
ing and the adjacent formation.
Potential problems with bentonite include
Relatively high pH of 8.5 to 10.5
High cation exchange capacity
These characteristics may impact the ambient
water chemistry; therefore, it is important to en-
sure that the seal is at least 2 to 3 feet above the
top of the well intakes.
6.4.4.7.4 Cement is a calcium carbonate mixture that
Cement when hydrated forms a hard, impermeable seal
in the annulus. Cement grouts are generally
mixed using 6.5 to 7 gallons of water per 94-
pound bag of Type I portland cement. Bentonite
may be added (5 to 10 percent) to the cement
grout to increase the elasticity of the grout.
Potential problems with utilizing cement as an an-
nular seal include:
Highly alkaline pH of 10 to 12
Relatively long set time
Shrinkage during setting
Aboveground mixing
6-30
-------
SECTION 6
Goundwater Monitoring
6.4.4.8 Surface seals are required to prevent surface
Surface Seal and runoff from entering the borehole annulus and to
Completion protect the well from damage. Surface seals are
constructed of cement and extend from the
ground surface to below the frost line. Two types
of surface completion structures are typically util-
ized for monitoring wells:
Above-grade completion
Flush completion
6.4.4.8.1 Above-grade-completed wells typically involve the
Above-Grade Completion placement of an outer protective casing around the
actual well casing. The protective casing is usually
steel or aluminum and is anchored into the cement
surface seal (pad) prior to setting. The finished pad
is sloped so that drainage will flow away from the
protective casing and off of the pad.
The protective casing should be equipped with a
cover that can be locked to prevent unauthorized
access. The dimensions of the protective casing
should be sufficient to provide clearance around
the inner well casing, i.e., should not contact the
inner well casing.
A vent hole should be drilled or cut into the top of
the well casing cap and in the outer protective
cover to permit pressure equalization. The pro-
tective casing should also have a weep hole
installed just above the interface with the con-
crete pad to prevent water from standing inside
of toe- protect ve-casing.
If above-grade-completed monitoring wells are lo-
cated in high traffic areas, additional protection
may be required (i.e., steel pipes, rails and/or
other steel structures). Steel barrier pipes, 3 to 4
6-31
-------
SECTION 6 Groundwater Monitoring
inches in diameter, are generally installed to a
minimum depth of 2 feet below the ground sur-
face and set in a concrete footing. The barriers
should extend a minimum of 3 feet above ground
surface or higher, if necessary, to provide good
visibility. Concrete can also be placed into the
steel pipe to provide additional strength.
6.4.4.8.2 Flush-completed wells are completed below the
Flush Completion ground surface. They are commonly utilized in high
traffic areas where above-grade completions would
disrupt surface activities or be subject to damage
(i.e., parking lots or roadways.) These wells involve
the utilization of a subsurface vault or well box that
is installed around the well casing. To protect from
heaving, the vault must be anchored below the
frost line. The well vault is sealed with a locking
flush-mount lid that prevents surface water infiltra-
tion. These wells should also be completed with a
water-tight well cap.
The well is accessed for sampling and/or meas-
urement from within the well vault. The water-
and air-tight nature of these seals affects water
levels in these wells. Upon opening the wells, the
water levels must be allowed to equilibrate prior
to measuring groundwater elevations.
Construction Methods
6.4.5 Construction methods for monitoring wells include:
Drilling techniques
Monitoring well development
Well construction documentation
Well abandonment
6-32
-------
SECTION 6
Goundwater Monitoring
6.4.5.1 Several drilling methods (Figure 6-11) are com-
Drilling Techniques monly used for installing groundwater monitoring
wells, including the following:
Auger drilling methods
Rotary drilling methods
Other drilling methods
Drilling method selection should be based upon
the following objectives'
Preserve the natural properties of the
subsurface formation materials.
Avoid contamination and/or cross-con-
tamination of aquifers.
Allow for collection of representative
samples of formation materials.
Provide for proper placement of well con-
struction materials including filter pack
and annular sealants.
Allow for elimination or removal of drilling-
induced impacts (i.e., fluids) and collec-
tion of representative groundwater
samples.
It is preferable, when possible, to select a drilling
method that allows for installation of the well ma-
terials (casing and screen), filter pack and
annular seals prior to removal of the drilling tools
(augers) or fluids (water). This is commonly done
when using hollow-stem augers to advance the
borehole. Construction of the well through the
6-33
-------
Drilling Methods for Various Types of
Geologic Settings
Geologic Environment
Drilling Methods
Solid-Stem
Continuous
Auger *
Hollow-Stem
Continuous
Auger
Water/Mud
Rotary
Air Rotary
Cable Tool
Glaciated or unconsolidated
materials less than 150 feet deep
Glaciated or unconsolidated
materials mdre than 150 feet deep
Consolidated rock formations less
than 500 feet deep (minimal or no
fractulred formations)
Consolidated rock formations less
than 500 feet deep (highly fractured
formations)
l
Consolidated rock formations more
than 500 feet deep (minimal
fractured formations)
Consolidated rock formations more
than 500 feet deep (highly fractured
formations)
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Note: Although several methods are suggested as appropriate for similar
conditions, one method may be more suitable than the others.
Figure 6-11
-------
SECTION 6
Goundwater Monitoring
augers helps to minimize construction problems
associated with borehole collapse.
Rotary wash drilling methods develop a drilling
mud (water and formation clays) which helps to
stabilize the borehole during well construction.
However, installation of the well materials must
be preceded by thinning or replacement of the
thick drilling mud with water; otherwise the mud
will become entrapped within the filter pack. In-
adequate removal of drilling mud prior to well
construction may make it impossible to ade-
quately develop the well after completion.
Two types of augers are commonly used for drill-
ing wells: solid-stem augers and hollow-stem
augers. Both types can be used in unconsoli-
dated soils and semi-consolidated (weathered
rock) materials, but not in competent rock. An ad-
vantage of auger drilling methods is that they
can be employed without introducing foreign ma-
terials into the borehole (i.e., drilling fluids), thus
minimizing the potential for cross-contamination.
Solid-stem augers consist of a solid stem or
shaft with a continuous, spiralled steel flight
welded to the stem (Figure 6-12). Auger sections
(flights) are connected to the auger bit. When ro-
tated, cuttings are transported to the surface.
This auger method can be used in cohesive and
semicohesive soils that do not have a tendency
to collapse when disturbed. Boreholes can be
augered to depths of 200 feet or more (depend-
ing on the auger size), but generally boreholes
are augered to depths less than 150 feet. Appli-
cations and limitations of solid-stem auger
drilling are presented in Figure 6-13.
6-35 RCRA Subtitle D Technical Training Manual
6.4.5.1.1
Auger Drilling Methods
6.4.5.1.1.1
-------
Diagram of a Solid-Stem Auger
(Source: EPA, 1989)
Cj
Auger
Connection _
Flighting
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Cutter Head
NT*>
Figure 6-12
-------
Applications and Limitations of
Solid-Stem Augers
Applications
Limitations
Shallow soils investigations
Unacceptable soil samples unless split-spoon or
thin-wall samples are taken
Soil samples
Soil sample data limited to areas and depths where
stable soils are predominant
Vadose zone monitoring wells
Unable to install monitoring wells in most
unconsolidated aquifers because of borehole caving
upon auger removal
Monitoring wells in saturated, stable
soils
Depth capability decreases as diameter of auger
increases
Identification of depth to bedrock
Monitoring well diameter limited by auger diameter
Figure 6-13
-------
SECTION 6
Groundwater Monitoring
Soil sample collection is difficult with solid-stem
augering because the soils are mixed by the con-
tinuous flighting of the cuttings. Monitoring well
installation may also be difficult because the
augers must be removed prior to placement of
the well materials, allowing for borehole collapse.
6.4.5.1.1.2 Hollow-stem augers consist of a hollow, steel
Hollow-Stem Auger stem or shaft with a continuous, spiralled steel
flight welded onto the exterior of the stem (Figure
6-14). As with solid-stem augers, the cuttings are
removed from the borehole by continuous flight-
ing. Hollow-stem augers are utilized in all
unconsolidated formations. Boreholes can be
augered to depths of 150 feet or more (depend-
ing on the auger size), but generally boreholes
are augered to depths less than 100 feet. Appli-
cations and limitations of hollow-stem auger
drilling are presented in Figure 6-15.
Unlike the solid-stem augers, the open-center
core allows the hollow-stem augers to act as a
temporary casing for soil sample collection and
well installation. Soil samples are commonly col-
lected with split-spoon or thin-walled (shelby
tube) samplers for characterization of site geol-
ogy (figures 6-16 and 6-17).
Monitoring wells can be installed inside hollow-
stem augers to reduce the potential for caving of
formation materials during placement of the well
materials. However, retracting the augers while
installing monitoring wells in caving formation
conditions can be difficult. A pilot-bit assembly or
bottom plug can be fastened to the bottom of the
augers to keep soils and/or water from clogging
the bottom of the augers during drilling (figures 6-
18 and 6-19). Sometimes potable water is
poured into the augers to equalize pressure and
6-38
-------
Diagram of a Hollow-Stem Auger
(Source: EPA, 1989)
Figure 6-14
-------
Applications and Limitations of
Hollow-Stem Augers
Applications
Limitations
All types of soil investigations
Permits good soil sampling
with split-spoon or thin-wail
samplers
Water Quality sampling
Monitoring well installation in
all unconsolidated formations
Can serve as temporary casing
for coring rock
Difficulty in preserving sample integrity in
heaving formations
Formation invasion by water or drilling mud if
used to control heaving
Possible cross contamination of aquifers where
annular space not positively controlled by water
or drilling mud or surface casing
Limited diameter of augers limits casing size
Smearing of clays may seal off aquifer to be
monitored
Can be used in stable formations to set surface
casing
Figure 6-15
-------
Sequential Steps in Hollow-Stem Drilling
and Sampling
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Figure 6-16
-------
Flexible Center Plug in Hollow-Stem
Auger Bit
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Figure 6-17
-------
Hollow-Stem Auger with Pilot-Bit
Assembly
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Figure 6-18
-------
Hollow-Stem Auger with Knock-Out
Bottom Plug
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Clean Water Level
Within Auger Column
Auger Column
-'.Ramrod:
Figure 6-19
-------
SECTION 6
Goundwater Monitoring
prevent the inflow of formation materials into the
augers when the bottom plug is removed.
6.4.5.1.2 Rotary drilling methods use a hollow drill pipe
Rotary drilling methods (drill stem) coupled to a drilling bit that rotates
and cuts through the soils (Figure 6-20). The cut-
tings produced from the rotation of the drilling bit
are transported to the surface by drilling fluids
which generally consist of water, drilling mud or
air. The drilling fluid is pumped down through the
drill pipe and out through the bottom of the drill-
ing bit (or the reverse - down the annular space
and up the drill pipe in reverse rotary drilling.)
The drilling fluids not only carry the cuttings to
the surface but also keep the drilling bit cool, sta-
bilize the borehole and prevent the inflow of
formation materials and fluids.
Rotary drilling provides for rapid borehole ad-
vancement in both consolidated and
unconsolidated formations and is not subject to
depth limitations. Applications and limitations of
direct mud rotary and air rotary drilling are pre-
sented in figures 6-21 and 6-22.
When considering rotary drilling methods, it is im-
portant to evaluate the potential for
contamination from the fluids introduced into the
borehole. Rotary drilling with water as the drilling
fluid is preferred, followed by air and, lastly, by
mud. The two rotary drilling methods most com-
monly utilized to construct monitoring well
boreholes are water rotary (rotary wash) and air ro-
tary drilling.
6.4.5.1.2.1 Rotary wash drilling (with water) is preferred for
Rotary wash drilling environmental drilling because potable water is
the only fluid introduced into the borehole during
drilling. The drilling water does not clog the for-
6-45
-------
Diagram of a Direct Rotary Drilling
System
/>S
Borehole wall
-------
Applications and Limitations of Direct
Mud Rotary Drilling
Applications
Limitations
Rapid drilling of clay, silt and reasonably
compacted sand and gravel
Difficult to remove drilling mud and wall cake from outer perimeter
of filter pack during development
Allows split-spoon or thin-wall sampling in
unconsolidated materials
Bentonite or other drilling fluid additives may influence quality of
groundwater samples
Allows core sampling in consolidated rock
Circulated (ditch) samples poor for monitoring well screen
selection
Drilling rigs widely available
Split-spoon and thin-wall samplers are expensive and of
questionable cost effectiveness at depths greater than 150 feet
Abundant and flexible range of tool sizes
and depth capabilities
Wireline coring techniques for sampling both unconsolidated and
consolidated formations often not available locally
Very sophisticated drilling and mud
programs available
Difficult to identify aquifers
Development of geophysical borehole logs
Drilling fluid invasion of permeable zones may compromise
validity of subsequent monitoring well samples
Figure 6-21
6-44
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5"
8-
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3'
-------
Applications and Limitations of Air Rotary
Drilling
Applications
Limitations
Rapid drillihg of semiconsolidated and
Surface casing frequently required to protect top of
consolidated rock
hole
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Good quality/reliable formation samples
(particularly if small quantities of water and
surfactant are used)
Drilling restricted to semiconsolidated and
consolidated formations
:o
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Equipment generally available
Samples reliable but occur as small particles that are
difficult to interpret
CD
D
Allows easy and quick identification of
Drying effect of air may mask lower yield
a
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lithologic changes
water-producing zones
Si.
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5'
5'
Allows identification of most water-bearing
zones
Air stream requires contaminant filtration
-------
SECTION 6
Goundwater Monitoring
mation materials, thus reducing well develop-
ment time. The drilling water will, however, flow
out into the surrounding formation materials (if
permeable) and mix with the natural formation
water Generally, most of the drilling water will
be recovered during well development.
Lithologic sample collection is good via split-
spoon and thin-walled samplers; however,
drilling fluid circulation must be stopped while the
drill string is removed and then replaced to col-
lect the samples.
6.4.5.1.2.2 Air rotary drilling utilizes air instead of water (or
Air rotary drilling mud) as the circulation medium. Compressed air is
forced through the drill rods to cool the bit and
force the cuttings up the annular space. This
method provides good lithologic samples and al-
lows good estimation of most water-bearing zones.
Air rotary drilling is difficult in unconsolidated for-
mations due to borehole collapse. The problem
can be alleviated with the utilization of a casing
driver that advances an outer casing along with
the rotary bit. Down-hole hammer bits are often
utilized in hard, consolidated formations to
achieve better penetration.
When using air rotary, an in-line organic filter sys-
tem must be installed on the air compressor to
filter the air coming from the compressor. Air
compressors that do not have in-line organic fil-
ter systems may introduce contaminants into the
borehole and formation. A cyclone velocity dissi-
pator or similar containment system should also
be used to funnel the cuttings to one location in-
stead of letting the cuttings blow uncontrolled out
of the borehole.
6-49
-------
SECTION 6
Groundwater Monitoring
6.4.5.1.2.3
Mud rotary drilling
6.4.5.1.3
Other Drilling Methods
6.4.5.1.4
Cleaning and
decontamination
Mud rotary is the least preferred rotary method
Drilling with mud (bentonite or other additives
mixed with water to create a thicker drilling fluid)
has the tendency to clog the water-bearing for-
mation and may influence the chemistry of the
groundwater. The drilling fluids lost to the forma-
tion will have to be removed during development
before the well can be sampled. Only potable
water and pure (no additives) bentonite drilling
muds should be used for environmental drilling.
Other types of drilling procedures are also avail-
able such as cable-tool (figures 6-23 and 6-24),
jetting and bucket-auger boring methods. These
methods are used in the installation of water and
irrigation wells, but are not commonly used for
monitoring well installation.
Drilling rigs, drilling and sampling equipment and
all other associated equipment involved in the
drilling, sampling and well construction activities
must be cleaned and decontaminated prior to
drilling each borehole. Oil or grease should not
be used to lubricate drill stem threads or any
other drilling equipment that might come in con-
tact with the borehole.
The well casing and screen materials must be
cleaned prior to installation, to remove any manu-
facturing residues, labeling or other materials
which they may have contacted.
6.4.5.2
Monitoring Well
Development
A monitoring well must be developed before a sam-
ple that is considered representative of
groundwater can be collected. The primary objec-
tive of monitoring well development is to restore the
formation adjacent to the well to its original (predrill-
ing) condition by correcting the damage inflicted on
the formation during drilling and construction of the
6-50
-------
Diagram of a Cable Tool Drilling System
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3"
-------
Applications and Limitations of Cable Tool
Drilling
Applications
Limitations
Drilling df all types of geologic
formations
Drilling relatively slow
Almost ahy depth and diameter
range
Heaving of unconsolidated materials must
be controlled
Ease of monitoring well installation
Equipment available more commonly in
central, north central and northeast sections
of the United States
Ease and practicality of well
development
Excellent samples of coarse-grained
materials
Figure 6-24
-------
SECTION 6
Goundwater Monitoring
well. All forms of well development require the re-
moval of water from the well.
Three factors influence the development of a
monitoring well:
Type of geologic material
Design and completion of the well
Type of drilling technology employed
The following procedures are generally used to
develop monitoring wells:
Bailing
Surging
Pumping/Overpumping/Backwashing
Air lift
These methods can be used either individually or
in combination to achieve the most effective well
development. Other development methods used in
water supply well applications are not recom-
mended because of their potential impacts on the
aquifer formation and groundwater chemistry.
Monitoring wells should be developed until the
water is free of visible sediment and the pH, tem-
perature and specific conductivity have
stabilized. In most cases, the above require-
ments can be satisfied; however, in some cases,
the pH, temperature and specific conductivity sta-
bilize, but the water remains turbid. When
groundwater remains turbid, the well may still
contain well construction materials (such as drill-
6-53
-------
SECTION 6
Groundwater Monitoring
ing mud in the form of a mud cake) and/or forma-
tion soils that have not been washed out of the
borehole.
Excessive or thick drilling muds cannot be
flushed out of a borehole with one or two well vol-
umes of purge water. Continuous flushing for
several days may be necessary to complete the
well development. Likewise, wells screened in
silty and clayey formations may require more ex-
tensive development to reduce turbidity.
In instances where the groundwater is contami-
nated or is suspected to be contaminated, the
well development procedures must address
health and safety precautions and proper stor-
age and disposal of the development water.
6.4.5.2.1
Bailing
Bailing is effective for developing shallow
monitoring wells in relatively clean, perme-
able formations. The alternative dropping and
retrieval of the bailer agitates the formation suffi-
ciently to remove the fine material from around
the filter pack. Bailing may be performed by
hand or with a drill rig setup.
6.4.5.2.2
Surging
Surging is performed by raising and dropping the
surging apparatus (i.e., surge block, pump,
bailer, etc.) to drive water into and out of the filter
pack. This in and out flow agitates the filter pack
causing proper seating of the filter pack materi-
als by disrupting bridging and helps to remove
fine particles trapped within the filter pack.
Surge blocks (Figure 6-25) are devices designed
for this purpose which can be raised and
dropped with a drill rig or in smaller and shal-
lower settings by hand. Surging can also be
used effectively in conjunction with bailing or
6-54
-------
Diagram of a Typical Surge Block
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Pipe
Rubber flap
Rubber disc
Pressure-relief hole
Steel or
wooden disc
(Source: Driscoll, 1986)
Figure 6-25
-------
SECTION 6 Groundwater Monitoring
pumping. The bailer or pump can be raised and
lowered causing the surging action between
evacuation episodes.
6.4.5.2.3 Pumping is a common method utilized to develop
Pumping/ monitoring wells. A pump is placed in the well to re-
overpumping/backwashing move water and to loosen particulate matter. With
overpumping, the pump rate is set at a level that ex-
ceeds the formation's ability to produce water,
thereby flushing out the filter pack more effectively.
In both methods, the pump must be periodically
stopped and started to allow water to recharge the
well. Backwashing ("rawhiding") or allowing water to
flow from the pump and piping back into the well can
impact water quality in the well. A similar surging ef-
fect can be produced by using the pump like a surge
block (raising and lowering) to loosen fine particles
and eliminate bridging of the filter pack materials.
The well is usually considered adequately devel-
oped when the turbidity, pH, temperature and
specific conductivity of the groundwater reach a
stabilized point. Stabilization is achieved after
three consistent, consecutive readings are
logged during the development.
6.4.5.2.4 Air lifting, using the eductor method (which does
Air Lift not expose the formation to the air or compressed
gas (nitrogen)), can be used to develop monitoring
wells. The air line is fed into the well through an
eductor pipe. The discharge point of the air line is
located within the eductor pipe allowing the air to
rise to the surface within the eductor pipe, drawing
formation water up with it. Direct air lifting (without
an eductor system) allows air to directly contact the
well materials and potentially impact water quality.
Direct air lifting is not recommended for develop-
ment of monitoring wells.
6-56
-------
SECTION 6
Goundwater Monitoring
6.4.5.3 All pertinent data collected during well construc-
Well Construction tion (drilling and development) operations should
Documentation be recorded in a field logbook. Each borehole lo-
cation should be recorded and referenced to the
site map and/or site datum (benchmark) so that
each location can be permanently established. It
is important that drilling logs be concise, com-
plete and presented in a manner that is easily
understood. Drilling and development informa-
tion that should be recorded as part of the
logging data includes the following:
Borehole number and location
Method of drilling
Type of drilling equipment, driller and
drilling company
Type of well (permanent or temporary)
Drilling and sampling dates and times
Depth of sampling and description
Type and size of casing
Type and size of well screen
Depth to well screen
Type of pump and pumping rate
Depth to water table and date and time
measured
Development method
Volume of water purged for development
6-57
-------
SECTION 6 Groundwater Monitoring
The well coordinates and elevations must be sur-
veyed and recorded as part of the construction
details. Elevations for the protective casing, top
of well casing (at a specified point or notch) and
grade should be surveyed by a licensed surveyor
to the nearest 0.01 foot.
6.4.5.4 When a decision is made to abandon a boring
Well Abandonment or monitoring well, the borehole must be
sealed in such a manner that it cannot act as a
conduit for migration of contaminants either
from the ground surface to the water table or
between aquifers. The preferred method of
abandonment is to completely remove any well
casing and screen from the borehole prior to
backfilling with an appropriate grout material
(cement or bentonite grout, neat cement or
concrete.) The backfill material should be
placed into the borehole from the bottom to the
top by pressure-grouting using the positive dis-
placement method (tremie method).
Wells that cannot be removed may have to be
grouted with the casing left in the borehole. In
this case, the tremie pipe should be placed near
the bottom of the well to allow the grout to fill the
well from the bottom to the top.
6.4.6 Placement of monitoring wells (i.e., number,
Placement of spacing and depths) to meet the groundwater
Monitoring Wells monitoring program objectives at MSWLFs re-
quires an understanding of the site
hydrogeology. Hydrogeologic factors which must
be considered when designing groundwater
monitoring systems include
Type of stratigraphy
Types of soils and/or rock
6-58
-------
SECTION 6
Goundwater Monitoring
Depth to bedrock
Saturated and unsaturated materials
overlying the uppermost aquifer
Materials comprising the uppermost aquifer
Materials comprising the lower boundary
of the uppermost aquifer
Depth to groundwater
Aquifer thickness
Groundwater flow direction and rate
Seasonal and temporal groundwater fluctua-
tions
Presence of perched water tables
Topography
Surface drainage patterns and features
Other factors which may affect groundwater
monitoring system design are:
Location of the landfill
Location of private and public water supply
wells
Location of surface water intakes
Municipal water service areas
Location of watersheds and recharge ar-
eas
6-59
-------
SECTION 6 Groundwater Monitoring
Location of 100-year floodplains
6.4.6.1 Visual inspection of the area may be sufficient to
Hydrogeologic evaluate and determine the surface conditions and
Characterization their general relationship to the subsurface condi-
tions. However, in most cases, surface and
subsurface conditions cannot be adequately corre-
lated by site inspections alone. Generally, more
detailed studies involving test drilling must be con-
ducted to adequately characterize the site
hydrogeology. Hydrogeologic characterization of
the site must be performed by qualified individuals.
Characterization of the local hydrogeologic set-
ting involves both review of available information
and site-specific hydrogeologic investigations.
6.4.6.1.1 A review of existing information on local and re-
Existing information gional geology and hydrogeology is the first step
in any hydrogeologic characterization study. The
site should be located on a U.S. Geological Sur-
vey (USGS) 7.5-minute topographic quadrangle
map, U.S. Department of Agriculture (USDA) soil
map, aerial photograph and any other appropri-
ate maps that show topography and general
relationships between surface features. This will
help to identify sources of available information
that will need to be reviewed.
Various local and regional sources of information
are available to obtain information on the site hy-
drogeologic setting. These sources include:
State Geological Surveys
State Department of Agriculture
USDA Soil Conservation Service (SCS)
Office
6-60
-------
SECTION 6
Goundwater Monitoring
U.S. Environmental Protection Agency
State Departments of Natural Resources
and Environmental Protection
State geological surveys and the USGS have
various types of water-related papers and re-
ports on all phases of groundwater studies in
each state. Other Federal agencies with water
programs which may provide information are:
Army Corps of Engineers
Bureau of Reclamation
Forest Service
Science and Education Administration
Public Health Service
Bureau of Mines
City and county governments also have depart-
ments that deal with water-related projects and
which may be able to provide data for the local
area. A review of wells installed in the area of inter-
est may provide background information on
subsurface conditions. Other sources include col-
leges, universities and professional/technical
associations such as the following: American Asso-
ciation of Petroleum Geologists, American Institute
of Mining and Metallurgical Engineers, American
Water Well Association, National Ground Water As-
sociation, Association of Engineering Geologists
and Geological Society of America.
Some states require well drillers to be licensed
and/or submit state-prescribed forms for report-
6-61
-------
SECTION 6
Groundwater Monitoring
6.4.6.1.2
Site-specific hydrogeologic
investigation
ing work performed on wells; these forms are
available to the public.
Site-specific hydrogeologic investigations must
be designed to adequately interpret the site geol-
ogy and hydrology; therefore, the scope of the
investigation is directly related to the complexity
of the underlying geology.
The hydrogeological investigation should include
the installation of boreholes, piezometers and
monitoring wells, as necessary, to evaluate the
properties of the materials comprising the under-
lying geologic units. These properties include:
Lithology
Thickness
Stratigraphy
Hydraulic conductivity
Porosity
Effective porosity
Depth to bedrock
Other geologic and hydrologic features which, if
present, must be characterized in the site-spe-
cific investigation include:
"Slopes
Streams
Springs
6-62
-------
SECTION 6
Goundwater Monitoring
Gullies
Trenches
Solution features
Karst terrain
Sinkholes
Dikes
Sills
Faults
Mines
Groundwater discharge features
Groundwater recharge/discharge areas
The site hydrogeologic characterization must
also consider natural and man-made conditions
that have the potential for causing water level
fluctuations, such as:
Tidal variations
River stage changes
Flood pool changes of reservoirs
High volume production wells
Injection wells
Site-specific hydrogeologic characterization stud-
ies should include the following components:
6-63
-------
SECTION 6
Groundwater Monitoring
Field observations
Drilling and materials testing programs
Other characterization techniques
Data presentation, interpretation and evalu-
ation
6.4.6.2 Field observations of the site should, at a mini-
Field Observations mum, include information on
Topographic setting
Springs, streams and other drainage fea-
tures
Existing or abandoned wells
Groundwater recharge and discharge
features
Rock outcrops (including trends in strike
and dip) and other features that may affect
site suitability or the ability to effectively
monitor the site
6.4.6.3 The drilling and materials testing program of a hy-
Drilling and Materials drogeologic characterization study should
Testing Programs provide for a sufficient number of boreholes, pie-
zometers and wells to use in developing an
adequate understanding of the subsurface condi-
tions and groundwater flow regime of the
uppermost aquifer at the site. The number and
depths of boreholes, piezometers and wells, as
described below, should be determined based
upon the homogeneity of the geologic and hydro-
geologic characteristics of the subsurface media.
6-64
-------
SECTION 6
Goundwater Monitoring
6.4.6.3.1 Exploratory boreholes should be installed to the
Boreholes bottom of the uppermost aquifer to determine the
aquifer thickness and composition of the lower
confining material. Continuous cores, while more
expensive than interval sampling (sampling on 5-
foot intervals), provide a better understanding of
lithology and site stratigraphy. Boreholes should
be installed systematically throughout the site un-
til an adequate quantity of data has been
collected to define subsurface conditions. Fac-
tors which influence the density of boreholes are
presented in Figure 6-26.
6.4.6.3.2 Piezometers are simplified or temporary well in-
Piezometers stallations designed to provide hydraulic head
(groundwater level) data at discrete intervals.
Piezometers are used to determine groundwater
levels and flow directions at the site. Piezome-
ters are cost-effective tools that aid in designing
monitoring systems with optimal well placement.
They can also be used to supplement collection
of water-level data from monitoring wells.
6.4.6.3.3
Monitoring wells
Initial monitoring wells should be installed at the
site to measure the hydraulic conductivity of the
various geologic materials. Hydraulic conductiv-
ity is generally measured by utilizing slug tests or
pumping tests, which are also effective tech-
niques to provide information on hydraulic
interconnection between the formations.
6.4.6.3.4
Materials-testing
Samples of geologic materials collected from the
'boreholes-should-be -tested to-determine the
properties of the materials which, at a minimum,
should include:
Formation descriptions
6-65
-------
Factors Influencing the Density of
Boreholes
Factors That May Substantiate
Reduced Density of Boreholes
Factors That May Substantiate
Increased Density of Boreholes
Simple geblogy (e.g., horizontal, thick,
homogeneous geologic strata that are
continuous across site and are
unfractured) substantiated by
site-specific geologic information.
Use of electric cone penetrometer
surveys with additional tools
(i.e., d.c. resistivity, sampling).
Use of surface geophysical methods to
correlate hydrogeologic data between
boreholes.
Fracture zones, conduits in karst
terrains.
Tilted or folded geologic formations.
Suspected pinchout zones
(i.e., discontinuous strata across the
site).
Laterally transitional geologic units
with irregular hydraulic conductivity
(e.g., sedimentary fades changes).
Figure 6-26
-------
SECTION 6
Goundwater Monitoring
Soil classification (based upon the Uni-
fied Soil Classification System)
Standard penetration-resistance
Soil moisture content
Grain size distribution
Soil particle specific gravity
Porosity and effective porosity
Hydraulic conductivity
6.4.6.4 Subsurface hydrogeologic conditions may be in-
Other Characterization vestigated using a variety of other geologic,
Techniques hydrologic, geophysical, geotechnical and engi-
neering techniques. Techniques that may be
used for hydrogeologic characterization studies
are summarized in Figure 6-27.
6.4.6.4.1
Data presentation,
interpretation and
evaluation
Geologic and hydrogeologic information must be in-
terpreted and evaluated before the
interrelationships between the individual pieces of
data can be understood. A variety of techniques
are used for presenting hydrogeologic information,
including:
Site location maps
Stratigraphic cross sections and
fence diagrams
Data tables and graphs
Potentiometric maps and flow nets
Narrative description
6-67
-------
Summary of Hydrogeologic Investigation
Techniques
Review of existing geologic information
Geophysical techniques (surface and borehole)
Mapping - topography, geology, soil
Cone penetrometer surveys
Aerial photography
Groundwater modeling
Review of available hydrologic information
Water levels measured in piezometers and wells
Aquifer tests (slug tests, pump tests, packer tests)
Vadose zone monitoring
Tracer studies
Groundwater quality analyses
Meteorological and climatological data gathering
Surface water chemistry and flow data Fiaure6-27
-------
SECTION 6
Goundwater Monitoring
Other information
These techniques are described below in more
detail. A detailed summary of other data presen-
tation and interpretation techniques is presented
in Figure 6-28a and Figure 6-28b.
6.4.6.4.2 A site map locating all soil boreholes, piezome-
Site location maps ters, monitoring wells and other relevant site
features is essential for proper interpretation of
geologic and hydrogeologic data. The site map
should be developed with accurate horizontal
and vertical control and, at a minimum, be tied to
a permanent onsite bench mark.
6.4.6.4.3 Cross sections and fence diagrams are graphic
Stratigraphic cross-sec- techniques for presenting and interpreting li-
tions and fence diagrams thologic and hydrogeologic data (figures 6-29
and 6-30.) These techniques are used to present
data from the individual boring logs and to ex-
trapolate between the boreholes to develop a
two- or three-dimensional understanding of sub-
surface geology and hydrology. Stratigraphic
and hydrogeologic (aquifers) units can be de-
picted as welt as potentiometric data.
6.4.6.4.4 Summarization of hydrogeologic data in tables
Data tables and graphs and graphs is essential to understanding the
data relationships. Data tables and graphs
should be used to prepare and support the inter-
pretations presented in the narrative discussion
of site hydrogeology. Examples of tabular and
graphic data presentations include:
Tables of groundwater and surface water
elevation data
Hydrographs of water elevation data for
individual wells
6-69
-------
Summary of Other Data Presentation and
Interpretation Techniques
Narrative summary of site geology and hydrology
Narrative summary of site geochemistry stratigraphic column
Geologic cross sections and fence diagrams
Topographic maps
Geologic maps
Soil maps
Boring and/or coring logs
Structure contour maps
Isopach maps
Raw data and interpretive analysis of surface and borehole
geophysical studies
Raw data and interpretive analysis of materials tests
Figure 6-28 a
-------
Summary of Other Data Presentation and
Interpretation Techniques (cont'd)
Aerial photographs
Results of modelling efforts
Piper, stiff and other geochemical diagrams
Hydrogeochemical maps
Water-table and potentiometric surface maps
Maps of recharge and discharge areas
Horizontal and vertical flow nets
Fracture trace maps
Maps of flow routes in karst terrains
Hydrographs
Estimates of hydraulic conductivity, hydraulic gradient,
rate of groundwater flow
Raw data and interpretive analysis of aquifer tests Figure 6-28 b
-------
Simple Geologic Cross Section
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Typical Fence Diagram
(Source: USDI, 1981)
Figure 6-30
-------
SECTION 6
Groundwater Monitoring
6.4.6.4.5
Potentiometric maps and
flow nets
Other information
Tabular and graphic presentations can be used
to:
Develop an understanding of seasonal
water table fluctuations
Estimate the long-term seasonal high
water table
Evaluate climatological impacts on ground-
water
Potentiometric maps and flow nets (figures 6-31
through 6-33) are techniques for evaluating the
horizontal and vertical aspects of groundwater
flow including
Flow directions
Flow rates
Hydraulic gradients
Potentiometric maps of water table and groundwa-
ter potentiometric surfaces (confined aquifers)
should be developed for each set of water-level
data. Each set of data provides additional informa-
tion on the long-term consistency and/or variability
of groundwater flow directions and rates.
Separate potentiometric maps must be devel-
oped for each aquifer or water-bearing zone that
is encountered at the site. The maps should in-
clude the location of all monitoring points
(boreholes, piezometers and monitoring wells)
and the groundwater elevation data at each loca-
tion used to generate the potentiometric
6-74
-------
Typical Potentiometric Map
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Interpolating Potentiometric Data
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Typical Flow Net
LEGEND
5.0 Equipolentlal Lines
ฆ+ฆ Approximate Groundwater
Flow Path
250'
Horizontal Scale
Figure 6-33
-------
SECTION 6 Groundwater Monitoring
contours. The direction of groundwater flow
should also be identified on the map.
Flow nets are similar to potentiometric maps in
their presentation of data, but their value is
generally less understood. Flow nets enable
presentation of the vertical component of ground-
water flow, which is essential to proper
placement of monitoring well screens to intercept
potential contaminant migration pathways.
6.4.6.4.6 Hydrogeologic characterizations should include a
Narrative Description of detailed narrative description of the geologic and
Hydrogeology hydrogeologic evaluations for the following two
very important reasons:
Many readers, with all levels of hydro-
geologic expertise, may be required to re-
view and/or use hydrogeologic
characterization information. Inadequate
explanation and/or clarification of inter-
pretations and conclusions may lead to
misunderstanding and/or misuse of the
information.
The procedures and methods used to in-
terpret and evaluate the hydrogeologic
data must be reproducible by other quali-
fied professionals at future dates when
additional information becomes avail-
able. Inadequate documentation of hydro-
geologic characterizations often
diminishes the quality and usefulness of
the data.
6.4.6.4.7 Other information including boring logs, field logs
Other information and notes, piezometer and well construction re-
cords and field observations provide valuable
information for characterizing site hydrogeology.
6-78
-------
SECTION 6
Goundwater Monitoring
6.4.6.5 Once the hydrogeologic characterization of the
Well Location Selection site has been completed, the groundwater moni-
toring system can be designed and installed.
The number and location of the monitoring wells
must be selected to monitor the pathways of con-
taminant migration and the background
groundwater quality.
Background wells should be placed upgradient
of the MSWLF or at other locations that provide
data that is representative of background ground-
water quality. Background wells must be
properly positioned to ensure that the groundwa-
ter collected from the well has not been
impacted by the MSWLF and that variabilities in
the background groundwater quality are as-
sessed. Multiple background wells may be
necessary to provide a better characterization of
groundwater quality variability and provide more
representative background data for statistical
analysis.
Downgradient wells must ensure adequate char-
acterization of groundwater passing through the
point of compliance (in approved states) or at the
MSWLF boundary (in unapproved states). The
wells must ensure the detection of contamination
in the uppermost aquifer. Typically, a series of
wells are installed along the downgradient bound-
ary of the MSWLF. The number and spacing of
the wells must be selected based on the site-spe-
cific hydrogeologic characterization. Generally,
the more complex the geologic settings, the
greater the number of monitoring wells that will
be required.
Numerous factors influence the spacing and
number of wells required to adequately monitor
6-79
-------
SECTION 6
Groundwater Monitoring
6.4.6.6
Groundwater Velocity and
Dispersivity
contaminant releases. These factors include the
following:
Type of wastes proposed for or disposed
at the MSWLF
Hydraulic gradients
Complexity of geology
Existence of preferential flow patterns
Groundwater velocity and transverse disper-
sivity
Detailed summaries of factors influencing well
spacing and number of wells per location are pre-
sented in figures 6-34 and 6-35.
Groundwater velocity and dispersivity are two
key factors in selecting well spacings. These
factors control the rate of longitudinal and lat-
eral (transverse) dispersion of contaminants in
the groundwater. Figure 6-36 shows examples of
contaminant migration in high- and low-velocity
groundwater settings. Contaminants will migrate
farther in the longitudinal direction in high velocity
settings, developing elongate plumes which can
pass between widely spaced monitoring wells.
The shape of a contaminant plume is also con-
trolled by the transverse dispersivity. Figure 6-37
presents a cross-sectional view of low- and high-
transverse dispersivity contaminant plumes.
High transverse dispersivities will result in
greater lateral spreading of contaminants in a
shorter distance. Sites with high groundwater ve-
locities and low transverse dispersivity will
require the closest well spacings.
6-80
-------
Factors Influencing Well Spacing
Wells Intervals May Be Closer If The Site:
Manages or has managed liquid waste
Is very small
Has fill material near the waste management
units (where preferential flow might occur)
Has buried pipes, utility trenches, etc.,
where a point-source leak might occur
Has complicated geology
- closely spaced fractures
- faults
- tight folds
- solution channels
- discontinuous structures
Has heterogeneous conditions
- variable hydraulic conductivity
- variable lithology
Is located in or near a recharge zone
Has a steep or variable hydraulic gradient
Is characterized by low dispersivity potential
Has a high seepage velocity
Well Intervals May Be Wider If The Site:
Has simple geology
- no fractures
- no faults
- no folds
- no solution channels
- continuous structures
Has homogeneous conditions
- uniform hydraulic conductivity
- uniform lithology
Has a low (flat) and constant hydraulic
gradient
Is characterized by high dispersivity
potential
Has a low seepage velocity
(Source: EPA, 1989)
Figure 6-34
-------
Factors Influencing Number of
Wells Per Location
One Well Per Sampling Location
More Than One Well Per Sampling
No "sinkers" or "floaters"
Presence of sinkers or floaters
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Thin flow zone
(relative to screen length)
Heterogeneous uppermost aquifer;
complicated geology
O
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Homogeneous uppermost aquifer;
simple geology
- multiple, interconnected aquifers
- variable lithology
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- perched water zone
- discontinuous structures
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2'
Discrete fracture zones
2*
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-------
Contaminant Migration in High- and Low
Velocity Groundwater Settings
(Source: EPA, 1990)
Figure 6-36
-------
Contaminant Migration in High- and Low-
Transverse Dispersity Settings
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Low Transverse Dispersivity
Figure 6-37
-------
SECTION 6
Goundwater Monitoring
6.4.6.7 infiltration of leachate through the landfill liner
oundmg Effects and m resu|t jn the mounding of the water table be-
Groundwater Reversals neath the unjt (Fjgure 6.38 } Thjs mounding
effect can influence the direction of groundwater
flow in the immediate vicinity of the MSWLF.
During operation of the groundwater monitoring
system, downgradient wells will have been used
to monitor for contaminant releases, and back-
ground wells will have been placed in upgradient
locations not normally subject to influence from
the landfill. When significant mounding occurs,
the area immediately surrounding the landfill, in
all directions, may be downgradient. This can re-
sult in contaminant migration to the upgradient or
background locations. When groundwater moni-
toring data indicates significant mounding, point
of compliance groundwater monitoring wells may
be required around the entire MSWLF unit.
Mounding or other changes in site hydrology
may result in seasonal or permanent reversals
of groundwater flow direction. Groundwater
flow reversals occur when water levels at the
downgradient monitoring locations rise and be-
come equal to or greater than the water level at
the upgradient edge of the unit. Mounding and/or
reversals in groundwater flow may require redes-
ign of the groundwater monitoring system.
6.4.6.8 Several examples of monitoring well siting sce-
Examples of Monitoring narios are presented in figures 6-39 through 6-51.
Well Siting Scenarios
6-85
-------
Mounding Effects on Contaminant
Migration
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Figure 6-38
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Monitoring System for Simple Geologic
Setting
l/PGRADปฃNT
BACKGROUND
WELL
CLUSTER
elevation
NOVO
MONITORINO
WELL
CLUSTER
2A2B 2C
\ ' ; 1 ' '.i v'".' :' * - 'i
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SANO K 1 0 * 1CT Jem/w<
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IANO K J 0 ฆ *0"~*cm/ปปe
i
100'
WELL AND SCREEN
y POfENTIOMETflIC SURFACE
f OR UPPERMOST SAND
7 POTENT10METRIC SURFACE
- FOR LOWER SAND
(Source EPA, 1989)
Figure 6-39
-------
Monitoring System for Complex Geologic
Setting
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LEGEND
backghound/upgradient WELL
# DOWNGRAD1ENT MONITORING WELL
WELL SCREEN
POTENTIOMETRIC SURFACE
. FRACTURED TRACE
OUTLINE OF CAVERN (PLAN VIEW)
loi PLUGGED BOREHOLE
WELL 2
-------
Contaminant Migration - Scenario 1
(Source:
EPA,
1977)
Figure 6-42
-------
Contaminant Migration - Scenario 2
Lv.-v
V'v
: WAT E R TA B L
x- L ANO SURFACE
3
3'
-------
Contaminant Migration - Scenario 3
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Contaminant Migration - Scenario 4
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(Source: EPA, 1977)
Figure 6-45
-------
Contaminant
Migration - Scenario
5
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Contaminant Migration - Scenario 6
(Source: EPA, 1977)
Figure 6-47
-------
Contaminant Migration - Scenario 7
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(Source: EPA, 1977) Figure 6-48
-------
Contaminant Migration - Scenario 8
CARBONATE ROCK
LEGEND:
0
CASING
OPEN HOLE
FLOW DIRECTION OF LEACHATE a LEACHATE-
ENRICHED GROUND WATER.
LEACHATE-ENRICHED GROUND WATER
A, B,C MONITORING WELLS
(Source: EPA, 1977)
Figure 6-49
-------
Contaminant Migration - Scenario 8
(Surface View)
I
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legend:
MONITORING
FLOW DIRECTION OF LEACHATE
ENRICHED OROUND WATER
LEACHATE ENRICHED
OROUND WATER
(Source: EPA, 1977)
Figure 6-50
-------
Contaminant Migration - Scenario 9
-------
SECTION 6
Groundwater Monitoring
6.5
GROUNDWATER
SAMPLING AND
ANALYTICAL
REQUIREMENTS
A groundwater monitoring program which in-
cludes a sampling and analysis program and
provisions for evaluating groundwater data must
be implemented at all regulated MSWLFs. The
sampling and analysis program must provide for
consistent procedures to ensure an accurate rep-
resentation of groundwater quality in background
and downgradient wells.
The sampling and analysis program must include
procedures for the following.
Sample collection
Sample preservation and shipment
Analytical procedures
Chain-of-custody control
Quality assurance and quality control
Statistical evaluation
Establishment of groundwater protection
standards
The monitoring program must also provide for
evaluation of groundwater analytical data using
appropriate statistical methods and evaluation of
groundwater flow direction and rate for each sam-
pling event.
6.5.1
Sample Collection
Typically, groundwater samples are collected as
grab samples: individual samples which are col-
lected from a single location at a specific time or
period of time generally not exceeding 15 min-
utes. Samples may be collected with bailers,
6-100
-------
SECTION 6
Goundwater Monitoring
pumps, suction devices or other techniques pro-
vided the sampling apparatus
Minimizes operator error
Can be decontaminated
Minimizes disturbance of the physical
and chemical nature of the groundwater
Allows for adequate flow control
Background samples should be collected before
downgradient samples to minimize the potential for
contamination of the background wells. Addition-
ally, all down-hole sampling equipment must be
thoroughly decontaminated to prevent cross-con-
tamination and the introduction of chemicals or
materials that may impact the groundwater chemis-
try.
Only sampling of monitoring wells is addressed
in the MSWLF regulations. However, groundwa-
ter monitoring may also be performed at other
types of wells (private and/or public water supply
and/or irrigation wells), groundwater discharges
(i.e., seeps and springs) or surface waters that
receive groundwater discharges.
Prior to sampling, the wells must be purged to en-
sure that the groundwater samples collected are
representative of the formation. Well purging and
sample collection procedures must be documented
in the field logbook. Each sample should be as-
signed a unique number to eliminate potential
interpretation errors. Sample volume and holding
times are dictated by the analytical method se-
lected. A generalized flow diagram of groundwater
sampling steps is presented in Figure 6-52.
6-101
-------
Generalized Flow Diagram of
Groundwater Sampling Steps
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STEPS
Well Inspection
Well Purging
Sample Collection,
Field Determinations
Preservation
Field Blanks
Standards
Storage Transport
PROCEDURES
Hydrologic Measurements
\
Removal or Isolation of Stagnant Water
I
Determination of Well-Purging Parameters
I
Volatile Organic Substances
i
Large Volume Samples for Organic
Compound Determinations
\
Trace Metal Samples and
Assorted Inorganic Species
(Source: EPA, 1987)
Figure 6-52
-------
SECTION 6 Goundwater Monitoring
6.5.1.1 Groundwater monitoring programs must include
Groundwater Level procedures for determining the water level at
Measurement each of the groundwater monitoring wells and/or
sampling stations. The measurement of ground-
water levels in monitoring wells (and other wells,
piezometers and surface water stations) is gener-
ally conducted in conjunction with sampling.
Groundwater levels are measured for two purposes:
Development of potentiometric maps
and determination of groundwater flow di-
rections and rates.
Determination of the presampling purge
volumes for each well.
Groundwater levels measured for development
of potentiometric maps must be collected in the
shortest possible time period to avoid temporal
variations in groundwater elevation data which
could preclude accurate determination of ground-
water flow directions and rates.
The water level and total well depth must also be
measured prior to purging to determine the
height of water in the well and the required purge
volume. The height of the column of water in the
well is the difference between the total depth of
the well and the depth to water (both measured
from the reference point on the top of the well
casing.) The height of the column of water can
then be used to calculate the volume of water in
the well. The volume of water in the well can be
determined by the following formula:
6-103
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SECTION 6
Groundwater Monitoring
V = 0.041 d2h
Where
V = volume of water in gallons
d = inside diameter of well in inches
h = depth of water in feet
A quick reference nomograph or table may be
used, if preferred.
Total well depth can be determined by lowering a
weighted tape or electric water level indicator to
the bottom of the well. Because of frictional and
buoyancy effects, it may be difficult to determine
when the tape end is touching the bottom of the
well. Care must be taken to ensure accurate
measurements. Total well depth measurements
should be recorded to the nearest 0.1 foot.
A variety of mechanical and/or electrical water
level indicator methods are used for measuring
groundwater levels, including:
Electric Water Level Indicator
Acoustic Water Level Indicator
Popper or Bell Sounder
Weighted Tape
Chalked Tape
Other Methods
These methods are described in more detail below:
6-104
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SECTION 6
Goundwater Monitoring
6.5.1.1.1
Electric Water Level
Indicator
This instrument consists of a spool of dual conduc-
tor wire, a probe attached to the end, and an
indicator (meter, light and/or buzzer.) A typical elec-
tric water level indicator is shown in Figure 6-53.
When the probe comes in contact with the water
the circuit is closed and the indicator registers the
contact. The depth to water is read from markings
on the wire. Measurements can be recorded to the
nearest 0.01 foot. This is the most commonly used
method for measuring groundwater levels.
6.5.1.1.2
Acoustic water level
indicator
Acoustic water level indicators which determine
water levels based on the measured return of an
emitted acoustical impulse are also available.
These instruments must be evaluated to ensure
that accurate measurements can be recorded to
the nearest 0.01 foot.
6.5.1.1.3
Popper or bell sounder
A bell- or cup-shaped weight that is hollow on
the bottom is attached to a measuring tape and
lowered into the well. A "popping" sound is made
when the weight strikes the surface of the water.
Measurements can only be accurately recorded
to the nearest 0.1 foot; therefore, this method is
not acceptable for measurements at MSWLFs.
6.5.1.1.4
Weighted tape
This method is similar to the "bell sounder"
method, except that any suitable weight, not nec-
essarily one designed to create an audible pop,
can be used to suspend the tape. Measurements
can only be accurately recorded to the nearest
0.1 foot; therefore, this method is not acceptable
for measurements at MSWLFs.
6.5.1.1.5
Chalked tape
Chalk rubbed on a weighted tape will discolor or
be removed when in contact with water. Dis-
tance to the water surface can be obtained by
subtracting the wet chalked length from the total
measured length. The tape must be withdrawn
6 -105
-------
Typical Electric Water Level Indicator
x.
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1
Reel and
Indicator
(Source: Johnson, 1975)
m
i Well Cosing
Electricol
w Coble
Contact
Electrode
Water
-------
SECTION 6
Goundwater Monitoring
from the well quickly because water will rise up
the chalk due to capillary action. Measurements
can be recorded to the nearest 0.01 foot; how-
ever, this method is not recommended if
samples are to be collected for analyses of or-
. ganic or inorganic contaminants.
6.5.1.1.6 There are other types of water level indicators
Other methods and recorders available, such as float recorders,
air line pressure methods and pressure
transducer recording methods. These methods
are primarily used for closed systems or perma-
nent monitoring wells. Accuracies for these
methods vary and should be evaluated before se-
lection. Any method not capable of providing
measurements to within 0.01 foot is not accept-
able for measurements at MSWLFs.
6.5.1.2 Monitoring wells must be purged before collect-
Purging ing groundwater samples. The purging objective
is to clear the well of stagnant water which is not
representative of aquifer conditions. Depending
upon well construction (diameter and depth), a
variety of purging methods may be used. Regard-
less of which method is used, the objective is to
remove nonrepresentative water.
Generally wells are purged of three to five times
the volume of water standing in the well or until
the values for groundwater indicator parameters
(pH, specific conductivity and temperature) stabilize.
Groundwater turbidity may also be a factor used to
determine when adequate purging has occured.
Normally, a combination of methods is employed
(i.e., pH, specific conductivity and temperature are
measured at intervals during the purging of three to
five volumes of water). Additional purging may be
required if the indicator parameters have not stabi-
6-107
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SECTION 6
Groundwater Monitoring
lized or if the sample turbidity has not been re-
duced to a level that will not impact analytical
results. Purging should continue until the objec-
tive of providing representative samples is
achieved.
If a well is purged dry, this generally constitutes an
adequate purge and the well can be sampled fol-
lowing recovery. However, purging should not be
conducted with the intention of purging the well dry
If a well is purged dry as a result of excessively
rapid evacuation, water that has been trapped in
the filter pack may inappropriately comprise the
sample. In addition, as water reenters the well, it
may cascade down the well screen, resulting in
stripping of volatile contaminants.
Well purging can be accomplished by using dedi-
cated pumps installed in the wells or, when
dedicated pumps are not available, by using
either peristaltic, turbine, bladder, centrifugal or
other appropriate pumps, depending on the well
depth. Purging with pumps should be performed
from the top of the standing water column and
not deep into the column. This is done so that
water will be pulled from the formation into the
screened area of the well and up through the cas-
ing to the point of removal, thereby removing the
entire static volume of water. If a purging pump
is placed deep into the water column, the water
above the pump may not be removed and the
subsequent samples collected may not be repre-
sentative of the groundwater.
Disposable, cleaned reusable or dedicated bail-
ers are commonly used to purge and sample
shallow monitoring wells. Purging with bailing re-
quires special precautions to prevent
volatilization of organic constituents and/or stir-
6-108
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SECTION 6
Goundwater Monitoring
ring up of sediments in the well. Bailers must be
lowered into and removed from the water column
gently to avoid creating turbulence.
6.5.1.3 All nondedicated or nondisposable purging and
Sampling Equipment sampling equipment (i.e., pumps or reusable bail-
Decontamination ers) must be decontaminated before placement
into each monitoring well. Disposable equipment
(i.e., ropes, hoses, etc.) must be replaced with new
materials before purging and sampling each well.
Careful consideration must be given to using
nondedicated equipment where wells are exces-
sively contaminated with oily compounds because
it may be difficult to adequately decontaminate the
equipment. Dedicated or disposable sampling
equipment should be used in highly contaminated
groundwater settings if possible.
6.5.1.4 Samples should be collected following purging in
Sampling Procedures wells that are not purged to dryness. Wells that are
purged dry can be sampled only after adequate re-
covery of groundwater for sample collection.
Groundwater samples are generally collected
with bailers and/or certain types of pumps (i.e.,
bladder pumps) or using the vacuum bottle
method (figures 6-54 through 6-56). Pumps used
for collecting groundwater samples must not ad-
versely impact the sample chemistry. Adverse
impacts can result from
Cavitation and/or excessive turbulence
Leaching of constituents from
pump/plumbing components
Direct contact of air or other fluids with
the sample
6-109
-------
Typical Sampling Bailer
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3-
3
8"
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3'
-------
Typical Bladder Pump
Sample line
Lifting bail
Discharge Check
Valve Assembly
(Inside Body)
o>
3)
O
ง
(/)
&
a:
ง
S
3-
O*
Q)
2
3'
(Q
I
3
c
0)
Perforated
Flow Tube
Bladder
Intake Check Valve
Assembly
(Inside Screen)
(Source: EPA, 1987)
Air Line
to Pressure
Annular
Space
Anti-Clogging
Screen
Figure 6-55
-------
Typical Vacuum Bottle Sample Collection
Method
Teflon Connector
6 mm ID
(Source: EPA, 1987)
Figure 6-56
-------
SECTION 6
Goundwater Monitoring
6.5.1.5 Filtering of groundwater samples collected for
Filtering monitoring at MSWLFs is not currently allowed.
However, it is generally understood that sample
turbidity may be a factor contributing to total con-
centrations of some inorganic (metal)
constituents and that proper monitoring well in-
stallation, development and well purging
techniques may not resolve turbidity problems.
Inorganic constituents (metals) associated with
suspended (particulate) matter in turbid samples
may adversely impact analytical results. When
problems with sample turbidity cannot be re-
solved through additional well development or
special purging and sampling precautions, it may
be practical to collect both filtered and nonfil-
tered samples. Both sets of data may enable
quantification of dissolved and suspended frac-
tions of inorganic constituents and help in
determining if releases have occurred or if met-
als concentrations are related to soil chemistry.
6-5-2 Once collected, the samples must be preserved
Sample Preservation and to ensure that the integrity of the samples is
Shipment maintained during shipment to the laboratory.
Preservation techniques are defined by the ana-
lytical methodology and include
pH control
Addition of chemicals
Temperature control
The samples must be packaged for shipment to
the laboratory in a manner that minimizes sam-
ple disturbance or potential for breakage.
6-113
-------
SECTION 6
Groundwater Monitoring
6.5.3 Chain-of-custody procedures are required to en-
Chain-of-Custody sure that the integrity of the samples can be
verified. These procedures include the labeling,
sealing and documentation of the samples. The
chain-of-custody tracks the handling of the sam-
ples from collection to analysis.
A sample or other physical evidence is in cus-
tody if it is-
In the sampler's actual possession;
In the sampler's view, after being in
his/her physical possession;
Secured to prevent tampering after being
in the sampler's physical possession; and
Placed in a designated secure area.
Sample custody must be documented on a
Chain-of-Custody Record which contains spaces
for the following information:
Project number;
Project or facility name;
Sampler's and/or sampling team leader's
signature;
Sampling location numbers, date and
time of sample collection;
Total number of sample containers for
each sample;
Total number of individual containers for
each type of analysis; and
6-114
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SECTION 6
Goundwater Monitoring
The samplers' and transferees' signa-
tures for each transfer of sample custody.
6.5.4 The selected analytical methodologies must be
Analytical Procedures sufficient to provide an accurate representation
of the groundwater quality. Rather than specify-
ing which analytical methods must be used, the
Subtitle D regulations require that the monitoring
program be protective of human health and the
environment. The regulations also require that
the statistical method selected to evaluate the
groundwater data use the lowest practical quanti-
tation limit (pql) that can be reliably achieved
within specified limits of precision and accuracy
during routine laboratory operating conditions.
Therefore, the analytical methods selected must
take into consideration the appropriate groundwa-
ter protection standards and provide for the
lowest practical quantitation limits.
6.5.5 Quality Assurance/Quality Control (QA/QC) pro-
Quality Assurance/ grams provide controls to ensure that field and
Quality Control analytical activities are performed in a consistent
and well-documented manner. The QA/QC pro-
cedures also ensure that the samples are
collected and evaluated accurately for site-re-
lated contamination. QA/QC programs may
require collection and analysis of additional sam-
ples for quality control purposes. The most
commonly collected quality control samples are
the following:
Split sample - A sample which has been
portioned into two or more containers
from a single sample container or sam-
ple mixing container.
Duplicate sample - Two or more sam-
ples collected simultaneously into sepa-
6-115
-------
SECTION 6
Groundwater Monitoring
rate containers from the same source un-
der identical conditions.
Trip blank -- Trip blanks are prepared
prior to the sampling event in the actual
sample container and are kept with the
investigative samples throughout the
sampling event. They are then packaged
for shipment with the other samples and
sent for analysis. At no time after their
preparation are the sample containers to
be opened before they reach the labora-
tory. Volatile organic trip blanks are used
to determine if samples were contami-
nated during storage and transportation
to the laboratory.
Equipment blank -- Equipment blanks
are defined as samples which are ob-
tained by running organic-free water
over/through sample collection equip-
ment after it has been cleaned. These
samples are used to determine if clean-
ing procedures were adequate.
Field blank Organic-free water is taken to
the field in sealed containers and poured
into the appropriate sample containers.
This is done to determine if any contami-
nants present in the area may have an
effect on the sample integrity. Field
blanks should be collected in dusty envi-
ronments and/or from areas where vola-
tile organic contamination is present in
the atmosphere and originating from a
source other than the source being sam-
pled.
6-116
-------
SECTION 6
Goundwater Monitoring
6.5.6
Statistical Evaluations
The QA/QC program should also include proce-
dures for field decontamination of reusable
equipment (if dedicated and/or disposable equip-
ment is not used) to eliminate the potential
cross-contamination of samples.
Sampling information should be recorded in
bound field logbooks. Preferably, a logbook
should be dedicated to an individual facility. All
entries should be dated and include the time of
entry. Furthermore, each page should be dated
and signed. A diagonal line should be drawn
(and initialed) at the end of any entries to void
any blank space.
All aspects of sample collection and handling, as
well as visual observations, should be docu-
mented in the field logbooks. All sample
collection equipment (where appropriate), field
analytical equipment and equipment utilized to
make physical measurements should be identi-
fied in the field logbooks. All calculations, results
and calibration data for field sampling, field ana-
lytical and field physical measurement
equipment should also be recorded in the field
logbooks.
All entries in field logbooks should be dated, leg-
ible and contain accurate documentation of
project activities.
The Subtitle D regulations identify the following
statistical methods for evaluating groundwater
data to determine if statistically significant in-
creases of chemical constituents have occurred:
Parametric Analysis of Variance
(ANOVA)
6-117
-------
SECTION 6
Groundwater Monitoring
ANOVA based on ranks
Tolerance or prediction intervals
Control chart
Other statistical methods
The regulations identify specific performance cri-
teria for selecting an appropriate statistical
method. The statistical method must
Be appropriate for the distribution of data
for the chemical parameters or hazard-
ous constituents being evaluated. Most
statistical methods assume a normal bell
curve distribution. If the distribution of
the data is not normal, then the data
must be transformed or a distribution-
free theory test must be used. More
than one statistical method may be
needed if the distributions for the con-
stituents differ.
Account for data below the limit of detec-
tion with one or more statistical proce-
dures.
Include procedures to control or correct
for seasonal and spatial variability as
well as temporal correlation in the data, if
necessary.
Use analytical data that has been de-
rived using the lowest pqls that can be re-
liably achieved.
The following Type I error performance stand-
ards apply to individual and multiple-comparison
6-118
-------
SECTJON 6
Goundwater Monitoring
procedures (but not tolerance intervals, predic-
tion intervals or control charts):
Individual well comparison procedures
used to compare data for individual com-
pliance wells with background concentra-
tions (or groundwater protection
standards) must be performed at a Type
I error level no less than 0.01 (i.e., 99
percent of the time a true statement
about the data will be accepted as true).
For multiple-comparison procedures, the
Type I experiment error rate must be no
less than 0.05 (95 percent of the time a
true statement will be found to be true).
6.5.6.1
Parametric ANOVA
Parametric ANOVA methods must include esti-
mation and testing of the contrasts between the
mean value for each point of compliance well
and the background mean value. These compari-
sons must be performed for each constituent
included in the monitoring program, as neces-
sary.
6.5.6.2
ANOVA Based on Ranks
ANOVA based on ranks method must include es-
timation and testing of the contrasts between the
median value for each compliance well constitu-
ent and the background median levels for that
constituent.
6.5.6.3 Tolerance or prediction interval procedures pro-
Tolerance or Prediction vide for the establishment of an acceptable
Intervals range of values for each constituent. The accept-
able range of values (values that could be
observed without there being a release) is de-
rived from the distribution of constituent
concentrations in the background data. The level
of each constituent in each compliance well is
6-119
-------
SECTION 6 Groundwater Monitoring
then compared to the upper limit (upper and
lower limits for pH) of the tolerance or prediction
interval to determine if a statistically significant in-
crease has occured.
6.5.6.4
Control Chart
A control chart approach gives control limits for
each constituent that when exceeded in a compli-
ance well indicates that a statistically significant
increase has occurred.
6.5.6.5
Other Statistical Methods
Other statistical test method(s) may be used pro-
vided they meet performance standards
identified above.
6.5.7
Groundwater Protection
Standards
Groundwater protection standards must be estab-
lished for each Appendix II constituent detected
in the groundwater. The groundwater protection
standard must be
The MCL, if one has been established
under the Safe Drinking Water Act;
The background concentration for the
constituent if no MCL exists;
The background concentration, if it is
higher than the MCL or health-based lev-
els; or
State-established alternative groundwa-
ter protection standards for constituents
with no established MCLs.
G&
CONTAMINANT FATE
AND TRANSPORT
PROCESSES
The basic understanding of the fate and trans-
port of contaminants in the subsurface can be
used to design cost-effective groundwater moni-
toring systems, safer waste disposal facilities
and subsequent corrective actions, if necessary.
The physical and chemical characteristics of the
6-120
-------
SECTION 6
Goundwater Monitoring
contaminants and the hydrogeologic settings of
the subsurface control the movement of contami-
nants in the porous media. The concepts of fate
and transport can be used to predict the time of
arrival and concentration of contaminants at a
designated receptor point (such as monitoring
wells, surface water bodies and water supply
wells.) The contaminants may exist in groundwa-
ter either in aqueous form or nonaqueous form.
The three fundamental processes through which
a contaminant is transported and transformed in
the subsurface include physical, chemical and
biological processes (Figure 6-57).
6.6.1 The four physical processes affecting contami-
Physical Processes nant fate and transport are
Advection
Dispersion
Diffusion
Retardation
6.6.1.1 Advection is the most important contaminant
Advection transport process. Contaminants are advectively
transported as a component of groundwater in di-
rect relation to groundwater flow. This process is
nonreactive and is controlled by the hydraulic
conductivity of the subsurface media and the hy-
draulic gradient. Advective transport is rate- and
direction-dependent.
6.6.1.2 Dispersion is the mixing of fluids due to the het-
Dispersion erogeneity of the media permeability (Figure
6-58). Typically, the dispersion mechanism re-
duces the contaminant concentrations in the
6-121
-------
Aqueous Phase Contaminant Fate and
Transport Process
Physical Processes
Chemical Processes
Biological Processes
Figure 6-57
-------
Dispersion in a Porous Media
o>
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o
2
CO
c
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?
ฃ
3-
0
2*
3'
3'
-------
SECTION 6
Groundwater Monitoring
plume by spreading to a greater extent both in
longitudinal and transverse directions. The longi-
tudinal dispersion is typically greater than
transverse dispersion by an order of magnitude
resulting in long and thin plumes. If transverse
dispersion is greater than longitudinal, the con-
taminant plume will spread over the entire
thickness of the aquifer.
6.6.1.3 Diffusion refers to the spreading of a contami-
Diffusion nant in response to concentration gradients.
Typically, in a homogenous porous media with
high permeability, the effect of diffusion proc-
esses are considered insignificant in comparison
to advection and dispersion. However, in low-per-
meability formations, such as clay liners,
diffusion is a dominant transport process. The
transport of inorganic ions through clay liners is
predominantly through diffusion.
6.6.1.4
Retardation
Retardation slows down the movement of con-
taminants in the porous media. Retardation is
dependent on chemical reactions such as sorp-
tion/desorption and the partitioning of
contaminants into the soil organic matter. The re-
tardation factor, in its simplest form, can be
defined as the ratio of velocity of the groundwa-
ter to the velocity of the contaminant in the
porous media.
6.6.2
Chemical Processes
The seven chemical processes affecting contami-
nant fate and transport are:
Sorption
Dissolution/precipitation
Acid-base reactions
-------
SECTION 6
Goundwater Monitoring
Complexation
Hydrolysis/substitution
Redox reactions
Radioactive decay
6.6.2.1 Sorption is the most important chemical process
Sorption controlling the rate of movement of contami-
nants. This process leads to the partitioning of
the contaminant between the groundwater and
the media. The organic content of the media and
contaminant solubility are key factors in sorption.
Sorption is typically represented as the partition-
ing coefficient (Kp) which is the ratio of
contaminant concentration in the soil fraction to
the contaminant concentration in the groundwa-
ter.
6.6.2.2
Dissolution/Precipitation
Dissolution and precipitation are chemical proc-
esses that either add contaminants to or remove
contaminants from the groundwater. Dissolution
of minerals in the media determines the natural
composition of groundwater. Precipitation is the
opposite of dissolution and involves the removal
of contaminants out of the aqueous solution.
These reactions are important attenuation
mechanisms that control the concentration of
contaminants in the groundwater.
6.6.2.3
Acid-Base Reactions
Acid-base reactions affect the pH of the ground-
water which in turn affect the rate of contaminant
solubility and transport.
6.6.2.4 In a complexation reaction, a metal ion reacts
Complexation with an anion (ligand). The metal and the ligand
bind together to form a new, more soluble spe-
cies, thereby increasing the contaminant
6-125
-------
SECTION 6
Groundwater Monitoring
6.6.2.5
Hydrolysis/Substitution
6.6.2.6
Redox Reactions
6.6.2.7
Radioactive Decay
6.6.3
Biological Processes
mobility. Complexation also decreases the
amount of "free" ions in solution which can ad-
sorb onto the media. Organic ligands generally
form stronger complexes. The common organic li-
gands are amines, pyridines, phenols and
naturally occurring humic materials. Inorganic li-
gands found in the subsurface include hydroxide,
chloride, ammonia, cyanide and polyphosphates.
Hydrolysis is the direct reaction of dissolved
compounds with water while substitution is the re-
action with a component ion of water. Hydrolysis
and substitution are important processes in abi-
otic (nonbilogical) chemical degradation.
Hydrolysis and substitution reactions often result
in organic compounds which are more soluble
and biodegradable.
The number of electrons associated with an ele-
ment dictates its oxidation state. Elements can
exist in several oxidation states. Redox (reduc-
tion-oxidation) reactions involve a change in the
oxidation state of elements (i.e., the transfer of
electrons.) Redox reactions affect contaminant
transport by influencing other chemical proc-
esses (i.e., solubility, adsorption, etc.) For
example: hexavalent chromium (Cr"6) is a toxic,
mobile anion whereas trivalent chromium (Cr"3)
is inert, relatively insoluble and strongly adsorbs
to surfaces. Redox reactions can result in the
creation of constituents which are more or less
harmful and/or mobile.
Radioactive decay is an irreversible decline in
the activity of a radionuclide through a nuclear re-
action.
Biological processes result in degradation and
transformation of organic compounds and incor-
6-126
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SECTION 6
Goundwater Monitoring
poration of inorganic ions in complex organic
compounds. The rates of biological processes
are controlled by the presence of microorgan-
isms and redox conditions. Biodegradation is
commonly used as a remediation process result-
ing in the reduction of contaminant
concentrations in the aquifer.
6.6.4
Nonaqueous-Phase
Liquids
Liquids that do not rapidly dissolve in water and
can exist as a separate fluid are known as
Nonaqueous-Phase Liquids (NAPLs) (Figure 6-
59). NAPLs are subdivided into two classes:
those that are lighter than water, Light NAPLs
(LNAPLs), and those with a density greater than
water, Dense NAPLs (DNAPLs).
NAPLs persist in the subsurface environment for
long periods of time and have the ability to con-
taminate large volumes of groundwater. Greater
understanding of the transport and dissolution of
NAPLs is necessary to implement cost-effective
monitoring and corrective actions.
6.6.4.1
Light Nonaqueous-Phase
Liquids
LNAPLs enter the unsaturated zone and flow
through the central portion of the unsaturated
zone. If the amount of LNAPL released is small,
the product will flow until residual saturation is
reached. Infiltrating water dissolves certain com-
ponents within the LNAPLs (e.g., benzene and
toluene) and carries them into the groundwater.
The dissolved constituent then forms a plume of
contaminants in the groundwater (Figure 6-60).
If a large volume of LNAPL is released, the prod-
uct flows through the unsaturated pore space to
the top of the saturated zone. As the head cre-
ated by the infiltrating product increases, the
water table is depressed and the product begins
to collect in the depressions. If the source of the
6-127
-------
Non Aqueous-Phase Liquids
LNAPLs
- Lighter than water
- Floats on water table
- Hydrocarbon fuels such as:
gasoline, fuel oil, heating oil and kerosene
DNAPLs
- Denser than water
- Chlorinated hydrocarbons such as:
TCE; PCE; 1,1,1-TCA and PCBs
Figure 6-59
-------
Movement of LNAPLs into the Subsurface
Oi
ro
-------
SECTION 6
Groundwater Monitoring
6.6.4.2
Dense Nonaqueous-
Phase Liquids
LNAPL is then removed, the LNAPL within the
vadose zone continues to flow under the influ-
ence of gravity until reaching residual saturation.
The LNAPL continues to collect on top of the
water table and spread laterally.
Seasonal water table variations result in the
spreading of contaminants (LNAPLs) over a
greater thickness of the aquifer.
DNAPLs can have great mobility in the subsur-
face as a result of their relatively low solubility,
high density and low viscosity. DNAPLs do not
readily mix with water and, therefore, remain as
a separate phase. The high density of these liq-
uids provides a driving force that can carry the
product deep into the aquifer. The combination
of high density and low viscosity is particularly im-
portant with regard to the transport of DNAPLs in
the subsurface.
DNAPLs flow through the unsaturated zone, to-
ward the water table, under the influence of gravity
(Figure 6-61). If the amount of DNAPLs released
is small, the material will be retained in the unsatu-
rated zone. Infiltrating water will dissolve the
residual DNAPL constituents and transport them to
the water table creating a separate dissolved
phased chemical contaminant plume.
If a greater amounts of DNAPLs are release, the
DNAPLs flow until reaching the saturated zone.
Once there, the DNAPLs begin to penetrate the
aquifer. However, to do this the DNAPLs must
displace the water by overcoming the capillary
forces between the water and the aquifer me-
dium. The critical height of DNAPLs required to
overcome the capillary forces varies for different
contaminants. After penetrating the aquifer, the
6-130
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Movement of DNAPLs into the Subsurface
o>
i
-a
CO
:o
O
Co
&
c*
s1
3-
I
21
3"
3*
-------
SECTION 6
Groundwater Monitoring
6.6.5
Delineation of Extent of
Contamination/Additional
Monitoring
DNAPLs continue through the saturated zone un-
til only a residual amount of the material is
retained in the unsaturated zone. The DNAPLs
are then dissolved by the passing groundwater
resulting in a plume of contaminated water.
Determining both the horizontal and vertical ex-
tent of a contaminant plume is a complex
problem. In addition to sampling through ground-
water monitoring wells, certain geophysical
testing can also be used. For example, if
leachate has high levels of total dissolved solids,
electrical resistivity surveys can be used to de-
lineate the plume. The location of additional
monitoring wells should be based on groundwa-
ter flow direction, site hydrogeologic settings and
the nature of the contaminants.
The placement of wells screened at varying
depths throughout the saturated zone of the up-
permost aquifer provides monitoring for
constituents that may exhibit preferential flow pat-
terns within the aquifer. Leachates that have
properties different from those of water may flow
through the soil/groundwater matrix at directions
and rates different from those of water, creating
flow patterns influenced by density variations. In-
stallation of well clusters may be required in thick
formations to avoid dilution of contaminants as
discussed in the section on groundwater monitor-
ing systems.
6-132
-------
SECTION 6
Goundwater Monitoring
References
1. U.S. Environmental Protection Agency, Compendium of Superfund Field
Operations Methods. EPA/540/P-871001a.
2. U.S. Environmental Protection Agency, RCRA Groundwater Monitoring
Technical Enforcement Document. OSWER Directive 9950.1 (1989a).
3. U.S. Environmental Protection Agency, Handbook of Suggested Practices
for the Design and Installation of Ground-Water Monitoring Wells.
EPA/600/4-89/034, PB90-159-807 (Washington, D.C.: Office of Research
and Development, 1989b).
4. U.S. Environmental Protection Agency, Transport and Fate of Contami-
nants in the Subsurface. EPA/625/4-89/019 (Cincinnati, OH: Center for
Environmental Research Information, 1989c).
5. U.S. Environmental Protection Agency, Handbook Ground Water.
EPA/625/6-87/016 (Ada, OK: R. S. Kerr Environmental Research Labora-
tory, 1987).
6. U.S. Environmental Protection Agency, Handbook Ground Water Volume
1: Ground Water and Contamination. EPA/625/6-90/016a (Washington,
D.C. Office of Research and Development, 1990a).
7. U.S. Environmental Protection Agency, Handbook Ground Water Volume
II: Methodology. EPA/625/6-90/016b (Washington, D.C.: Office of Re-
search and Development, 1991)
8. U.S. Environmental Protection Agency, Test Methods for Evaluating Solid
Waste - Physical/Chemical Methods (SW-846) (Washington, D.C: Office
of Solid Waste and Emergency Response).
9. U.S. Environmental Protection Agency, RCRA Ground Water Monitoring:
Draft Technical Guidance (Rockville, MD: Office of Solid Waste, Govern-
ment Institutes, Inc., 1992).
6-133
-------
SECTION 6
Groundwater Monitoring
10. U.S. Environmental Protection Agency, Procedures Manual for Ground-
Water Monitoring at Solid Waste Disposal Facilities. EPA/530/SW-611
(Cincinnati, OH: Office of Solid Waste, 1977).
11. U.S. Department of the Interior, Ground Water Manual: A Water Re-
sources Technical Publication (Washington, D.C.: Water and Power Re-
sources Service, 1981).
12. Ralph C. Heath, Groundwater Regions of the United States. U.S. Geologi-
cal Survey Water-Supply Paper 2242 (1984).
13. David M. Nielsen. Practical Handbook of Ground-Water Monitoring (Chel-
sea, Michigan: Lewis Publishers, 1991).
14. Johnson Division, UOP Inc., Ground Water and Wells (St. Paul, Minne-
sota: 1975).
15. Fletcher G. Driscoll, Groundwater and Wells. Second Edition. Johnson Di-
vision (St. Paul, Minnesota: 1996).
16. Michael J. Barcelona, et al., A Guide to the Selection of Materials for
Monitoring Well Construction and Groundwater Sampling (Champaign, Illi-
nois: Illinois State Water Survey, Department of Energy and Natural Re-
sources, 1983).
6-134
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SECTION 7.0
Corrective Action
Page No.
7.1 CORRECTIVE ACTION AS END RESULT 7-1
-------
SECTION 7
Corrective Action
7.1
CORRECTIVE
ACTION AS END
RESULT
The Subtitle D regulations include requirements
for corrective actions to address contaminant re-
leases to groundwater. Although corrective ac-
tion is beyond the scope of this course, the
following brief discussion is included.
MSWLFs are required to implement a Corrective
Action Program if a statistically significant in-
crease above the groundwater protection stand-
ard has occurred for any of the Appendix II
constituents. The Corrective Action Program
must include:
Characterization of the nature and extent
of the release
Assessment of corrective measures
Remedy selection and implementation
Characterization of the nature and extent of any re-
lease is required as a component of the assess-
ment monitoring program which precedes
assessment of corrective measures. However, ad-
ditional characterization may be necessary to facili-
tate adequate assessment of corrective measures.
Assessment of corrective measures must be initi-
ated within 90 days after determination that a sta-
tistically significant increase of Appendix II
constituents has occurred. The assessment
must evaluate the effectiveness of potential cor-
rective measures to meet the regulatory require-
ments and objectives for remedial actions. Each
applicable corrective measure must be assessed
to determine the following:
7-1
-------
SECTION 7
Corrective Action
Performance
Reliability
Ease of implementation
Potential impacts (safety, cross media
and exposure)
Time required to begin and complete
the remedy
Costs of implementation
Institutional requirements (i.e., state or lo-
cal permits or other environmental or
public health requirements)
The assessment of corrective measures must be
completed within a reasonable period of time.
Upon completion, the results of the assessment
must be discussed in a public meeting prior to
formal selection of the remedy.
The corrective remedy selected must meet the
following standards:
Be protective of human health and the
environment
Attain the groundwater protection standard
Control the source(s) so as to reduce or
eliminate further releases
A number of factors must be considered in se-
lecting corrective remedies:
7-2
-------
SECTION 7
Corrective Action
Long- and short-term effectiveness and
protection
Long-term reliability
Short-term risks during implementation
Potential reduction of existing risks and
residual risks
Effectiveness in controlling further
releases
Type and degree of long-term manage-
ment required
Time required to achieve full protection
Potential for exposure to remaining
wastes
Potential need for replacement of the
remedy components
Degree of difficulty associated with im-
plementation
Availability of equipment and specialists
Availability, capacity and location of treat-
ment, storage and disposal services
Need to coordinate and obtain approvals
and permits
Degree to which community concerns
are addressed
7-3
-------
SECTION 7
Corrective Action
Technical and economic capability of the
responsible parties
The corrective remedy must include the following
components:
Interim measures (as necessary) to en-
sure the protection of human health and
the environment
Schedule for implementation and completion
Establishment of a corrective action
groundwater monitoring program
The corrective remedy must included a schedule for
initiating and completing remedial activities within a
reasonable period of time. The following factors
should be considered in developing the schedule:
Extent and nature of contamination
Practical capabilities of the remedy to
achieve the remedial objectives
Availability of treatment or disposal ca-
pacity for wastes generated
Desirability of utilizing future technolo-
gies which may offer significant advan-
tages over available technologies
Potential risks from exposure to contami-
nation prior to completion
Resource value of the aquifer
Practicable capability of the responsi-
ble party
7-4
-------
SECTION 7
Corrective Action
Corrective action remedies are considered com-
plete when the following requirements are met:
The groundwater protection standards
have not been exceeded (using the statisti-
cal procedures) for a period of three con-
secutive years
All actions required to complete the rem-
edy have been satisfied
7-5
-------
SECTION 7 Corrective Action
7-6
-------
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ATTACHMENT A
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FLEXIBLE MEMBRANE LUfER-S
Gregory N. Richardson
1. INTRODUCTION
This session discusses material and design considerations for
flexible membrane liners (FMLs) within solid waste facilities
constructed to satisfy 6NYCRR Part 360. It highlights some
of the problems encountered in applying the 1-dimensional
regulatory liner profile to actual 3-dimensional landfill
"bathtub" systems. Under Part 3 60, the minimum acceptable
liner profiles for municipal solid waste landfills are as
follows (360-2.13):
Primary Leachate Collector (24-inch @ 10~3 cm/sec)
Primary Composite Liner (18-inch *(see note} + FML)
Secondary Leachate Collector (12-inch @ 10cm/sec)
Secondary Composite Liner (24-inch @10"7 cm/sec + FML)
The soil component of the primary composite liner is required
to achieve less than lxlO"7 cm/sec permeability only in the
upper -6-inch.es. To minimize potential compaction induce
damage to the secondary composite liner, the lower 12-inches
of the soil' component in the primary composite must only
achieve lxlO"5 cm/sec. permeability. For slopes greater than
25%, the primary liner consists of only an FML and a geonet
can be used to construct the secondary leachate collection
system. These concessions are made due to slope stability
considerations as discussed later in this session.
COMPOSITE LINERS: CLAY VERSUS FML
The reliance within Parr 3 60 on composite liners composed of
a synthetic FML overlying a lower permeability soil is an
extension of EPA's minimum technology guidance for hazardous
waste containment systems. The advantages of a composite
liner have been clearly established and will be discussed
herein.
Understanding the basic hydraulic mechanisms for synthetic
liners and clay liners is very important in appreciating the
advantages of a composite liner. Clay liners are controlled
by Darcy's law (Q = kiA) . In clay liners, the factors that
most influence liner performance are hydraulic head and soil
permeability. Clay liners have a higher hydraulic
conductivity and thickness than do synthetic liners.
Additionally, leachate leaking through a clay liner will
* upper 6 inches @ 10 cm/sec, lower 12 inches @ 10 "5 cm/sec
-------
undergo chemical reactions that reduce the concentration of
contaminants in the leachate.
Leakage through a synthetic liner is controlled by Fick's
first law, which applies to the process of liquid diffusion
through the liner membrane. The diffusion process is similar
to flow governed by Darcy' s law except it is driven by
concentration gradients and not by hydraulic head. Diffusion
rates in membranes are very low in comparison to hydraulic
flow rates even in clays. In synthetic liners, therefore, the
factor that most influences liner performance is penetrations.
Synthetic liners may have imperfect seams or pinholes, which
can greatly increase the amount of leachate that leaks out of
the landfill.
EPA's rationale for favoring a composite liner system is based
both on increasing the efficiency of the liquid collection
systems and to reduce the potential for leakage-^out of the
liner system. A laboratory evaluation of the reduced leakage
rates afforded by composite liners was funded by EPA in the
late 80's. Table 1 is extracted from this study and clearly
shows that a composite liner will reduce'leakage orders of
magnitude when compared to an FML resting on a drainage media.
The key requirement in this improved performance from
composite liner is that both components of the liner must be
in intimate contact. Thus the introduction of a geotextile
beneath the FML will destroy the composite action of the two
components and result in a significant increase in leakage.
Accordingly, the use of a geotextile beneath an FML to
increase the puncture resistance of the FML is dangerous.
3 . MATERIAL CONSIDERATIONS
Synthetics are made up of polymers-natural or synthetic
compounds of high molecular weight. Under Part 360, the only
restrictions on the selection of a polymer are 1) the FML must
have a minimum thickness of 60 mils,2 ) the FML must have a
permeability less than lxlO"12 cm/sec, and 3) . The FML must
not chemically react with the anticipated leachate. Different
polymeric materials may be used in the construction of FMLs:
Thermoplastics-polyvinyl chloride (PVC)
Crystalline thermoplastics-high density polyethylene
(HDPE), linear low density polyethylene (LLDPE)
Thermoplastic elastomers-chlorinated polyethylene (CPE) ,
chlorylsulfonated polyethylene (CSPE)
Elastomers-neoprene, ethylene propylene diene monomer
(EPDM)
-------
Typical compositions of polymeric geomembranes are depicted in
Table 2. As the table shows, the membranes contain various
admixtures such as oils and fillers that are added to aid
manufacturing of the FML but may affect future performance. In
addition, many polymer FMLs will cure once installed, and the
strength and elongation characteristics of certain FMLs will change
with time. It is important therefore to select polymers for FML
construction with care. Chemical compatibility, manufacturing
considerations, stress-strain characteristics, survivability, and
permeability are some of the key issues that must be considered.
3 .1 CHEMICAL COMPATIBILITY
The chemical compatibility of a FML with waste leachate is an
important material consideration. Chemical compatibility and
EPA Method 9090 tests must be performed on the synthetics that
will be used to construct FMLs. (EPA Method 9090^-tests are
discussed in more detail in Session Five.) Unfortunately,
there usually is a lag period between the time these tests are
performed and the actual construction of a facility. It is
very rare that at the time of the 9090 test, enough material
is purchased to construct the liner. This means that the
material used for testing is not typically from the same
production lot as the synthetics installed in the field.
The molecular structure of different polymers can be analyzed
through differential scanning calorimeter or thermogravimetric
testing. This testing or "fingerprinting" can ensure that the
same material used for the 9090 test was used in the field.
Figure 1 was provided by a HDPE manufacturer, and the
fingerprints depicted are all from high density polyethylenes.
Chemical compatibility of extrusion welding rods with
polyethylene sheets is also a concern.
3 . 2 MANUFACTURING CONSIDERATIONS
FML sheets are produced in various ways:
Extrusion-HDPE
Calendaring-PVC
Spraying-Urethane
In general, manufacturers are producing high quality
geomembrane sheets. However, the compatibility of extrusion
welding rods and high density polyethylene sheets can be a
-------
polyethylene to crease. When this material creases, stress
fractures will result. If the material - is taken into the
field to be placed, abrasion damage will occur on the creases.
Manufacturers have been working to resolve this problem and,
for the most par, sheets of acceptable quality are not being
produced.
STRESS-STRAJN CHARACTERISTICS
Table 3 depicts typical mechanical properties of HDPE, CPE,
and PVC. Tensile strength is a fundamental design
consideration. Figure 2 shows the uniaxial stress-strain
performance of HDPE, CPE, and PVC. As 600, 800, 1,100, and
1,300 percent strain is developed, the samples fail. When
biaxial tension is applied to HDPE, the material fails at
strains less than 20 percent. In fact, HDPE can fail at
strains much less than other flexible membranes when subjected
to biaxial tensions common in the field.
Another stress-strain consideration is that high density
polyethylene, a material used frequently at hazardous waste
facilities, has a high degree of thermal coefficient of
expansion - three to four times that of other flexible
membranes. This means that during the course of a day
(particularly in the summer) , 100-degrees Fahrenheit (ฐF)
variations in the temperature of the sheeting are routinely
measured. A 600-foot long panel, for example, may grow 6 feet
during a day.
3 .3 SURVIVABILITY
Various test may be used to determine the survivability of
unexposed polymeric geomembranes (Table 4) . Puncture tests
frequently are used to estimate the survivability of FMLs in
the field. During a puncture test, a 5/16 steel rod with
rounded edges is pushed down through the membrane. A very
flexible membrane that has a high strain capacity under
biaxial tension may allow that rod to penetrate almost to the
bottom of the chamber rupture. Such a membrane has a very low
penetration force but a very high penetration elongation, and
may have great survivability in the field. High density
polyethylenes will give a very high penetration force, but
have very high brittle failure. Thus, puncture data may not
properly predict field survivability.
3.4 PERMEABILITY
Permeability of a FML is evaluated using the Water Vapor
Transmission test (ASTM E96) . A sample of the membrane is
placed on top of a small aluminum cup containing a small
-------
amount of water. The cup is then placed in a controlled
humidity and temperature chamber. The humidity in the chamber
is typically 20 percent relative humidity, "while the humidity
in the cup is 100 percent. Thus, a concentration gradient is
set up across the membrane. Moisture diffuses through "the
membrane and with the liquid level in the cup is reduced. The
rate at which moisture is moving through the membrane is
measured. From that rate, the permeability of the membrane
is calculated with the simple diffusion equation (Fick's first
law). It is important to remember than even if a liner is
installed correctly with no holes, penetrations, punctures,
or defects, liquid will still diffuse through the membrane.
A final comment must be made regarding the Part 360
requirement for 10"12 cm/sec permeability in the FML. Table 5
lists WVT data for Typical FML*s. The water vapor permeance
is defined as the WVT divided by the pressure difference
across the FML. Permeability is then defined as the product
of the permeance and thickness of the FML. Tabl6 5 lists
equivalent permeabilities for common FML's. If the FML must
have less than lxlO"12 cm/sec permeability, then a polyethylene
liner will be required.
TABLE 5 FML PERMEABILITY
(Data from Haxo, 1989)
Polymer
Thickness
Mils
WVT(1)
crm"2 d-l
Permeability(2)
cm/sec
CPE
30
38
.32
.55
2xl0~12
4xl0'12
CSPE
30
38
. 60
.41
4X10"12
3xl0"12
EPDM
38
.25
1.6X10*12
LDPE
30
.05
3.2X10"13
HDPE
30
100
.0177
.006
lxlO"13
1X3X10"11
PVC
20
30
3.0
1.8
1x3x10
1X3X10"11
[1) lgn 2 d 1.07 gallon/acre/day
(2). 1 metric perm mil = 2.l67xl0~12 cm/sec
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4. DESIGN ELEMENTS
A number of design elements must be considered in the
construction of flexible membrane liners: (1) 6NYCRR Part 360
guidance, (2) stress considerations, (3) structural details,
and (4) panel fabrication.
4 .1 6NYCRR PART 360 GUIDANCE
Part 3 60 establishes minimum values for the components within
the landfill liner. For the FML component, these minimum
values are:
60 mil minimum thickness, and
Permeability less than lxlO"12 cm/sec.
Thus the basic design will begin with these values
4.2 STRESS
Stress considerations must be considered for side slopes and
the bottom of a landfill. For side slopes, self-weight (the
weight of the membrane itself) and waste settlement must be
considered; for the bottom of the facility, localized
settlement and normal compression must be considered.
The primary FML must be able to support its own weight on the
side slopes. In order to calculate self-weight, the FML
specific gravity, friction angle, FML thickness, and FML yield
stress must be known (Figure 3).
Waste settlement is another consideration. As waste settles
in the landfill, a downward force will act on the primary FML.
A low friction component between the FML and underlying
material, putting tension on the primary FML. A 12-inch
direct shear test is used to measure the frict:.on angle
between the FML and underlying material.
An example of the effects of waste settlement can be
illustrated by a recent incident at a hazardous waste landfill
facility in California. At this facility, waste settlement
led to sliding of the waste, causing the standpipes (used to
monitor secondary leachate collection sumps) to move 60 to 90
feet downslope in 1 day. Because there was a very low
coefficient of friction between the primary liner and the
geonet, the waste (which was deposited in a canyon) slid down
the canyon. There was also a failure zone between the
secondary liner and the clay. A two-dimensional slope
stability analysis at the site indicated a factor of safety
greater-than one. A three-dimensional slope stability
-------
analysis of the canyon landfill indicated a factor of safety
greater than one. A three-dimensional slope stability
anaylsis, however, showed the safety factor had dropped below
one. Three-dimensional slope stability analyses should
therefore be considered with canyon and trench landfills.
Since more trenches are being used in double FML landfills,
the impact of waste settlement along such trenches should be
considered- Figure 4 is a simple evaluation of the impact of
waste settlement along trenches on the FML. Settlements along
trenches will cause strain in the membrane, even if the trench
is a very minor ditch. Recalling that when biaxial tension
is applied to high density polyethylene, the material fails
at a 16 to 17 percent strain, it is possible that the membrane
will fail at a moderate settlement ratio.
Another consideration is the normal load placed on the
membranes as waste is piled higher. Many of the new materials
on the market, particularly some of the linear low density
polyethylene (LLDPE) liners, will take a tremendous amount of
normal load without failure. The high density polyethylenes,
on the other hand, have a tendency to high brittle failure.
4. 3 STRUCTURAL DETAILS
Double liner systems are more prone to defects in the
structural details (anchorage, access ramps, collection
standpipes, and penetrations) than single liner systems.
4.3.1 Anchorage
Anchor trenches can cause FMLs to fail in one of two way:
by ripping or by pulling out. The pullout mode is
easier to correct, it is possible to calculate pullout
capacity for FMLs placed in various anchorage
configurations (Figure 5) . In the "V" anchor
configuration, resistance can be increased by increasing
the "V" angle. A drawback to using the WV" design is
that it uses more space. The concrete trench is rarely
used. Typical calculations for these anchorage
configurations are given in Figure 6.
No rigorous solution exists for a common soil backfilled
anchorage trench. In general a trench 12-inches wide by
12 to 18-inches deep will be sufficient to develop the
full tensile capacity of the FML. Trenches larger than
this will only lead to a tearing failure in the membrane.
-------
4.3.2 Ramps
Most facilities have access ramps (Figure 7), which are
used by trucks during construction and by trucks bringing
waste into the facility. Figure 8 depicts a cross section
of a typical access ramp. The double FML integrity must
be maintained over the entire surface of the ramp.
Because ramps can fail due to traffic-induced sliding,
roadway considerations, and drainage, these three factors
must be considered during the design and construction of
access ramps.
The weight of the roadway, the weight of a vehicle on the
roadway, and the vehicle braking force all must be
considered when evaluating the potential for slippage due
to traffic (Figure 9). The vehicle braking fprce should
be much larger than the dead weight of the vehicles that
will use it. Wheelloads also have an impact on the
double FML system and the two leachate collection systems
below the roadway. Trucks with maximijm axle loads (some
much higher than the legal highway loads) and 90 psi
tires should be able to use the ramps. Figure 10
illustrates how to verify that wheel contact loading will
not damage the FML. Swells or small drains may be
constructed along the inboard side of a roadway to ensure
that the ramp will adequately drain water from the
roadway. Figure 11 illustrates how to verify that a ramp
will drain water adequately. The liner system, which
must be protected from tires, should be armored in the
area of the drainage swells. A sand subgrade contained
by a geotextile beneath the roadway can prevent local
sloughing and local slope failures along the side of the
roadway where the drains are located. The sand subgrade
tied together with geotextile layers forms, basically,
long sandbags stacked on top of one another.
4.3.3 Vertical Standpjpes
Landfills have two leachate collection and removal
systems (LCRSs) : a primary LCRS and a secondary LCRS.
any leachate that penetrates the primary system and
enters the secondary system must be removed. Vertical
standpipes are used to access the primary leachate
collection stamps. As waste settles over time, downdrag
forces can have an impact on standpipes. Those downdrag
forces can lead to puncture of the primary FML beneath
the standpipe.
-------
To reduce the amount of downdrag force on the waste pile,
standpipes can be coated with viscous or low friction
coating. Standpipes can be encapsulated with coefficient
of friction that helps reduce the amount of downdrge
force on the waste piles. Figure 12 illustrates how to
evaluate the potential downdrag forces acting on
standpipes and how to compare coatings for reducing these
forces.
Downdrag forces also affect the foundation or subgrade
beneath the standpipe. If the foundation is rigid,
poured concrete, there is a potential for significant
strain gradients. A flexible foundation will provide a
more gradual transition and spread the distribution of
contact pressures over a larger portion of the FML than
will a rigid foundation. To soften rigid foundations,
encapsulated steel plates may be installed beneath the
foundation as shown in Figure 13.
4.3.4 Standpipe Penetrations
The secondary leachate collection system may be accessed
by either a sidewall standpipe that penetrates the
primary liner above the waste mass, or by a sump gravity
drain pipe that lies below the landfill containment
system (Figure 14) . Both standpipes have key operational
weaknesses. The sidewall standpipe must be accessible
at the surface so that a pump can be lowered to the sump.
Because .there is a possibility that the sump pipe could
be struck at the surface, it should not be attached in
any manner to either liners. The gravity drain line lies
beyond the secondary liner so that failure of this line
would result in release of leachate to the environment.
For this reason, a double-wall pipe is recommended
between the sump and the catchbasin.
4.3.5 Wind Damage
During the installation of FMLs, care must be taken to
avoid damage from wind. Figure 15 shows maximum wind
speeds in the United States. Designers should determine
if wind will affect an installation and, if so, how many
sandbags will be needed to anchor the FML panels as they
are being placed in the field. Figure 16 shows how to
calculate the required sandbag spacing for FML panels
during placements. Wind-uplift pressure must be known
to make this calculation. Using the data in Table 5, the
uplift pressures acting on the membranes may be
calculated. Note that 6NYCRR Part 6 does not allow FML
placement in winds exceeding 20 mph.
-------
4 . 4 PANEL FABRICATION
The final design aspect to consider is the FML panel layout
of the facility. Three factors should be considered when
designing a FML panel layout: (1) seams should run up and down
on the slope, not horizontally; (2) the field seam length
should be minimized whenever possible; and (3) when possible,
there should be no penetration of a FML below the top of the
waste.
6NYCRR Part 360 specifically requires that field seams should
be oriented parallel to the line of the maximum slope, that
the number of field seams- should be minimized in corners and
irregularly-shaped locations, and that no horizontal seams
should be less than 5-feet from the toe of the slope toward
the inside of the cell.
Panels must be properly identified to know where they fit in
the facility. Figure 17 depicts the panel-seam identification
scheme used for this purpose. This numbering scheme also
assures a high quality installation, since seam numbers are
used to inventory all samples cut from the' FML panel during
installation. The samples cut from the panels are tested to
ensure the installation is of high quality. Quality assurance
and the panel-seam identification scheme are discussed in more
detail in Session VI.
REFERENCES
Brown, K. W. et al, Qualification of Leak Rates Through Holes in
Landfill Liners, EPA Grant Nol. CR810940, EPA Office of Research
and Development, 1987.
Haxo, H.E., 1983. Analysis and Fingerprinting of Unexposed and
Exposed Polymeric Membrane Liners. Proceedings of the Ninth Annual
Research Symposium., Land Disposal of Hazardous Waste, U.S. EPA
600/8-83/108.
Haxo, H.E., 1988, Lining of Waste Containment and Other Impoundment
Facilities, EPA/600/2-88/052.
Knipschield, F.W. 1985. Material, Selection, and Dimensioning of
Geomembranes for Groundwater Protection, Waste and Refuse. Schmidt
Publisher, Vol. 22.
Richardson, G.N. and R. M. Koerner, 1988, Geosynthetic Design
Guidance for Hazardous Waste Landfill Cells and Surface
Impoundments, EPA/600/52-87/097.
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TABLE 1 CALCULATED FLOW RATES (M^ YR~ ) FOR A RANGE OF
HOLE SIZES IN FLEXIBLE MEMBRANE LINERS OVER SOILS
OF DIFFERENT CONDUCTIVITIES. THE VALUES ARE GIVEN
FOR THREE HEADS
Hole diaaeCer (cm)
K (cm/ s) 0.08 0.16 0.64 1.27
sac
H - 0.3 M
3.AO x 10~J 19.30 31.50 43.20 50.60
3.40 x 10 4.30 4.88 6.28 7.30
3.40 x 10"ฐ 0.54 0.60 0.77 0.89
3.40 x 10 0.066 0.072 0.095 0.107
H - 1.0 M
1.30 x 10~f 126.10 2,286.00 6,748.00
3.40 x 10 42.30 87.80 128.00 147.00
3.40 x 10~^ 12.80 14.. 80 18.70 21.40
3.40 x 10": 1.66 1.83 2.29 2.61
3.40 x 10 0.20 0.22 0.28 0.32
H - 10.0 M
3.40 x lO'J 167.0 438.0 1,030.00 1,170.00
3.40 x 10"^ '84.6 123.1 153.^0 171.30
3.40 x 10 , 14.3 15.6 18.80 21.00
3.40 x 10~7 1.8 1.9 2.30 2.60
Table Z Basic Composition o< Polymeric GeomamOrana
Comoosition ol Comoouno Tyoe
loans ov weซgnil
Comoonent
Crossunxea
Thermooiasuc
Semicrystaiiine
Polymer or alloy
100
100
100
Oil or piasocaer
S-40
5-55
0-10
Fillers:
5-vO
S-40
2-5
Caroon Slack
S-*0
5-40
"
Inorganics
1
AnMegraaants
1-2
1-2
Crcastmkinq system:
5-9
Inorganic system
**
Sulfur system
5-9
Source: Haxo. H. E. 1986. Quality Assurance at Geomemoranes Usea as Lirunqs lor Hazaraous Waste Containment. in: Geotexmes anu
Geomemoranes. Vol. 3. No. 4. Lonoon. England.
-------
Table 3 Typical Mechanical Properties
Density. grrvcmJ
Thermal coefficient of exoansion
Tensile strengtn. psi
P-jncture. itvmii
HOPE
>935
12.5 i 10-5
1800
2.3
CPE
1.3 1.37
4 t 10 s
1600
1.2
PVC
'.2* 1.3
3 ซ 10-s
2200
2.2
Tabla 4 Test Methods for Unexposed Polymeric Geometnbranes
Memorane Uner Without Fabric Remtorcemert
Prooanv
Thennooiastic
CrossMwaa
Semcrysiannfl
FlOnc flewitorceo
Analytical Properties
Volatries
Extractaoes
Asn
Soeaftc gravity
Thermal analysis:
Oitterenoai scanning
caionmetry <0SC)
Thermoqravtmeiry
(TGAJ
MTM-tซ MTM-1ซ MTM-1* MTM-M
ion setvage ana
euiloicea sneennqj
MTM-2" MTM-2* MTM-2* MTM-2*
(on setvage ana
remlorcea sneenngi
ASTM 0297. Section 34 ASTM 0297. Section 3* ASTM 0297. Sec=on 34 ASTM 0297. Sacoon 34
(on setvaqel
ASTM 0792. Memoo A ASTM 0297. Section IS ASTM 0792. Metnoa A ASTM 0792. Memoa A
(on setvagei
NA
Yes
NA
Yes
Yes
Yes
NA
Yea
Physical Prccerees
Thickness - total
Coating over faonc
Ten sua prooerties
Tear resistance
Moauius of elasticity
Haraness
Puncture resistance
Hyorostaac resistanca
Seam strengtn:
in snear
in oeei
Ply aanesion
ASTM 0638
NA
ASTM 0882.
ASTM 0638
ASTM 0100*
(mocrfieai
NA
ASTM 02240
Quro A or 0
r i MS 101B.
Metnoa 2065
NA
ASTM 0882. Metnoa A
(mooihea)
ASTM 0413. Macn
Metnoa Type i
(moaiheai
NA
ASTM 0ซ12
NA
ASTM 0412
ASTM 0624
NA
ASTM 02240
Qura A or 0
FTMS 1018.
Metnoa 2065
NA
ASTM 0882. Metnoa A
(moartieai
ASTM 0413. Macn
Metnoa Tyoe i
(moartieat
NA
ASTM 0633
NA
ASTM 0638
(moaned)
ASTM 01004
Ota C
ASTM 0882. Memoo A
ASTM 02240
Oura A or 0
FTMS 1010.
Metnoa 2063
ASTM 0731. Metnoa A
ASTM 0882. Metnoa A
(moafwal
ASTM 0411 Maai
Metnoa Type i
(moahea)
NA
ASTM 0731. Secoon 6
Ooocai metnoa
ASTM 0751. Metnoa A
ana 8 (ASTM 0638 on
sewage i
ASTM 0751. Tongue
metnoa (moaifiea)
NA
ASTM 02240 Oura A
or 0 (sewage onty)
FTMS 1018.
Metnoas 2031 ana 2065
ASTM 07S1. Metnoa A
ASTM 07S1. Metnoa a
(modified)
ASTM 0413. Macn
Metnoa Type t
(moarfwa)
ASTM 0413. Macn
Metnoa Type l
ASTM 0751. Secsans
39-42
Environmental ana Aping
Effects
Ozone craaung ASTM 01149
Environmental stress NA
cracxmg
Low wmoeraure testing ASTM Ot790
Teniae oroocroes ai
eievaiea temoerature
nxnAnvmrial staDUKV
ASTM 0638 (moarfieai
ASTM 01204
ASTM 01149
NA
NA
ASTM 01693
ASTM 01790
ASTM 0746
ASTM 0746
ASTM 0412 (moartwai ASTM 0638 Imoarfieoi
ASTM 01204 ASTM 01204
ASTM 01140
NA
ASTM 02136
ASTM 0731 Metnoa 8
(moaiheai
-------
Tab)* J Wind-Uplift Forces, PSF (Factory Mutual System^
Height Wind Isotacfi. mon
Above "
Grouna _
City. Suburoan Areas. Towns, and Wooded Areas
Flat Ooen Country, or Ooen Coastal Sett > 1500 ft from Coast
(ft)
70
80
90
100
110
70
80
90
100
110 120
0-15
10*
11
14
17
20
14
18
23
29
35 14
30
10
13
17
21
25
16
21
27
33
40 48
50
12
15
19
24
29
18
24
30
37
44 3S
75
14
18
22
27
33
20
26
33
40
49 8S
-------
iao*c. aoo osq
rune (mini
Figure i Comparison of "fingerprints'* of exothermic peak
shapes.
Strain. %
Figure I FML stress-strain performance
(uniaxial-Koerner. Richardson; biaxialStaff en).
-------
1
CaU Component: riuiftu M^mpgxuc liutff
- L.uftt Unr.Hr ;
A4ซtซrv # f Mi iur mm
f*XWUO f-
4ซTV 0ซU
Analysis Procedure:
"TV bj JปP ^ /
UMซซ< U*UM<ซ UmNT
( FML TปmปK Cป
C T/h, wmซm i'ซ t
OftT^w Lurnrw^ tซu> ffT
5nซซซ
(4^ 0ซ4'Vo iWปt
(t> FhC- lio^ut ^TซCr> v 6*
<7 \t,a/C* * "Tซ7 ^ * ?*- >*/***
' ฃ. */ ~1
PMC *>llC7
Hiqugf
C*JI Component: ft_i*.iป<.E MtMoatut LimlK
Consideration: L^urco 5wmoซ.ซi : E.ซW*J*ri ซซ4IWซ HAMซ0
i fHt lซrikWlซ* MliVtMa.
Required Material Properties Range Test Standard
Fml
ฆ ^HL
Kmcu.
frM ซM taw ~
0>ซ<ซr^wซ>i
A>^
Analysts Procedure:
(ซฆ>ฃ.
^i|
t~t T*T
* Uซซซซ ซ/l* #
~V C.f%^
' CHซ. ' nO* t#l n#*ซ cซm
~ TVซM4M t*mป IY i4Hซ
(t) ป fT^w glซi< ^T. ~~
d" (*.L]/C
il fcl
S(TTUM(Nr tAno, s/n
Example:
* Uo^. HOPE
" 1lwซs4
* FsmT
* G\j (+ <*?
t > UI l I
. -\
+ + ~*M
10*
1"'
(0 ฃซf ซX*t ฃwป*04lJ4<.
*ซ" "7 <ฆ_ o
V ^ซiniM4wT Kซ
Ck/*- j
C*"J I , 3-^
6 - to7.
(*)^ci.,n Awtfn... Lt*-srM
lw> OM(ซ
I.[iB5j...ซ
1.1 IUM
(ปl g.Y~- <,Tซ
ซ.Y to 7.
- 'ฆป* 7.
o*
~z
-------
TcoปP
ZF&P
Covซr Sซl
"^sy/A-y
ii
I I . 1 J I
Tiln^
HOtllONTAl AMCHOff
r &ซซซ
$k0m+r+v
- twi iMl( ^
'I' ฆฆฆฆ HซM4|4w
fU Sซwt fซซ Awjua
ปป-T~
***Srr
.'v'Tmn
U*<0.
.i.r
t. r^ปWM-4^-^-r3
1** * t'-C* ^
flC-K.-JT
IB-
_.!a-1.xL1 UปJitrtfrซ-uปซซ*ปซซซ1 . _lv*
T- ld-5 J5?>'
T*ซmt
-+-3ป--ซ<.-.4Cfc ... , 5
| ^i iwlซn~aVl n tfi n-aT>-ซซt wซ.t1 . ^2p>ป^T
*' _* ซ i
>ฆ 1 Jซ. i.ปป1
Examoto No. i.\7
A-18
-------
igura 7 Geometry ot typical ramp.
Flqurn 8 Cross section of typical access ramp.
Cell Component: R ซ.
Consideration: a-~-' ฆ>
guO(d <>ซ*0
Required Material Properties Range Test Standard
5-i^e /ฆซ.,
r*<*-.
LC& - rt.
># ซK
5.
.
. f -
14 fซ#
4jn-
Analysts Procedure-*
(0C?fc*.ซ4 f**
U," ซ/ |ซidU4
Uซ '
6* a fc.
^ rปaซtaป
r-
References:
Exampie:
ซ ( u ,
* c^^' ป ฉ' UuAfV* |iซ fl"
|Vm/ ฃ" rtM
1*^ Q+*-*L
II > ; t - .*ซ>nr *i%ปซ T*Uป*~ปป Tปt
U*^-r ' Wป*-- * C*. *.*
r# ป /#ซ<{ *
$ -
I ^ OZeJ*** 4 pg
C7G\
(-vซOtw) O*
1.41
OB
^
>ซ6
i.n
>*o 94rwซi\j
ictf *w* (ซ>(T.ซU Jt^lC $ ,-^
Example No. 4.1
Rqur*
-------
Cell Component:!?
Consideration: U***"- ซ.ปr >
X fnl..
Required Material Properties
PML C'
?ปฆ'*ฆ ฆ Sjซum fn**ru* ^
Range
Test
ซwซv
Standard
A1W Wj*ma
Analysis Procedure:
(O 0<^^ซ P***ปp
Amim^ ฃ;| P.<ซ*wPw<
ซซซฆ<
R*ซrrcATwซ, cAซwt ^ c^f^x
[ P/r ^ ] 1 Aaiu uav
7ccซ%j fซX
4
I
PtMtWUll I ^ /
*"" "*" '**ป ^
IIIMIill
Dir-.-C DOiw gซ.r- Qg
DR -
*M-ซป , s~""
ซ aM%< * (.*ฆ** <3J " '{ฃปซซ
O' TW>cซmo L' 14"
^
r;> C..S
(1J rifctwซซ fl-lL 5lTiw^T* . t
Diซ^m
CVt- JO
pe ฆ
HITM
1 ioซ^Ar*bt
Required Material Properties
P( , K , 0* -fflcu*. vt
Range
1#
Test
t;-^ ฆฆ ปt
/ซ* oiwfT
Standard
jLซM044ซr
Analysts Procedure:
(O 6 fuPvt* q
S^l#4ซ4
V4*T*ซ
Wซ4ซ4 C* !ซ
t* (MU#Uti , ปHH /Uซi
yปiVi iป , am(ซ
(t) fc*
r* ป* (Xgป g>
S2iฑ3 ซ.5
References:
Example:
Ulvr*ซ : UAitii*(ป *
Xป ซWซU,* 1ซซyLw^
P.-ซ.ปLCซ : <ป *. Io**ซ*Aftc' r,ซyUe
O'CTXw,
* I f 5 ป.4 ป 1.2 ft*/ mc
(OF,
r>-~>
-------
figure. VI, Evaluation of potential QOwndrag forces on standpipes witti ana witnout coating.
Fiqura (3, Details or standpipedrain.
-------
Primary FML
Weid
3#
' Seconaary FML
"V
"Sev>iOca2>Mป
JF^U** 14" "Rpe- T-cnaemATi OKLS
-------
Cell Component: MiM&aAut
Consideration: T-* " *A,;
p Pkwt ojซ>m< 'lu( 4 ปปf
Required Material Properties
uซป^4ซo
V 'to
uJ.mซ . iซo r*.
FVllPlPrw *ฃ o -ป '1ฐ *r
ซ Jo lb 0 | mxm, to
' H|^ซf Tm Ff-i 't^fr OCr *Lปfr
11 > PfT< *ฆซป 4 Qซ >'ป
ฆ3 *r 14
& f( ซป < 6 *
w -o S^c ^'u,.s
-to *r """ S9i6 /,, 0%r v
ฐ" 3oซป ' t* t
Wo #r So <ป, .ฆ* t
( *N Ol *.<1 ^ ^
T.b *ซ. c t
i.T i.e.
* *5 r
-2*fr
r.3/.o.
ซ a t*j *4^
J ป* *' J-T/^-o ; ^
7o ซ"r ^ ฃ-Vซ-ซ 1 O ป< j
example No. io.\
-------
A,
A A AAA
A
/IK
A
A
A
A
(53) \
(27)
4 Xj
ฃ,
(28
/
''<3>
A^
(21)
ฉ ! ฉ
A
~r
0 i ฉ
I
Toe at Slope
0
ฉ
O
0i0i0
i i
0
0
ฉ
/>
/<ง
0
A
A
0
0
A
A
0
\
0 N
>4
A A A A
Panel Numoer
A Seam Numoer
A
/10.
A' A
Figure 17 Panel-seam identtficaiton schema.
O U.S. GOVERNMENT PRINTING 0FF1CE:1 W2-ซซe-003/4tB02
-------
-------
ATTACHMENT B
-------
METHOD 9090
COMPATIBILITY TEST FOR WASTES ANO MEMBRANE LINERS
1.0 SCOPE ANO APPLICATION
1.1 Method 9090 Is Intended for use 1n determining the effects of
chemicals In a surface Impoundment, waste pile, or landfill on the physical
properties of flexible membrane liner (FML) materials Intended to contain
them. Data from these tests will assist In deciding whether a given Uner
material Is acceptable for the Intended application.
2.0 SUMMARY OF METHOD
2.1 In order to estimate waste/liner compatibility, the liner material
1s immersed in the chemical environment for minimum periods of 120 days at
room temperature (23 + 2*C) and at 50 + 2*C. In cases where the FML will be
used In a chemical environment at elevated temperatures, the Immersion testing
shall be run at the elevated temperatures if they arejsxpected to be higher
than 50*C. Whenever possible, the use of longer exposure times is
recommended. Comparison of measurements of the membrane's physical
properties, taken periodically before and after contact with the waste fluid,
is used to estimate the compatibility of the liner with the waste over time.
3.0 INTERFERENCES (Not Applicable)
4.0 APPARATUS ANO MATERIALS
NOTE: In general, the following definitions will be used In this method:
1. Sample a representative piece of the liner material proposed for
use that Is of sufficient size to allow far the removal of
all necessary specimens.
2. Specimen a piece of material, cut from a sample, appropriately
shaped and prepared so that 1t is ready to use for a test.
4.1 Exposure tank: Of a size sufficient to contain the sample?;, with
provisions for supporting the samples so that they do not touch the bottom or
sides of the tank or each other, and for stirring the liquid 1n the tank. The
tank should be compatible with the waste fluid and impermeable to any of the
constituents they are intended to contain. The tank shall be equipped with a
means for maintaining the solution at room temperature (23 + 2* C.) and 50 +
2*C and for preventing evaporation of the solution (e.g., use a cover equippeH
with a reflux condenser, or seal the tank with a Teflon gasket and use an
airtight cover). Both sides of the Uner material shall be exposed to the
chemical environment. The pressure Inside the tank must be the: same as that
outside the tank. If the liner has a side that (1) 1s not ปปxposed to the
9090 - 1
Rev1 :s 1 on 0
-------
waste 1n actual use and (2) 1s not designed to withstand exposure to the
chemical environment, then such a liner may be treated with only the barrier
surface exposed.
4.2 Stress-strain machine suitable for measuring elongation, tensile
strength, tear resistance, puncture resistance, modulus of elasticity, and ply.
adhesion.
4.3 Jig for testing puncture resistance for use with FTMS 101C, Method
2065.
4.4 Liner sample labels and holders made of materials known to be
resistant to the specific wastes.
4.5 Oven at 105 + 2#C.
4.6 Dial micrometer.
4.7 Analytical balance.
4.8 Apparatus for determining extractable content of liner materials.
NOTE: A minimum quantity of representative waste fluid necessary to
conduct this test has not been specified 1n this method because
the amount will vary depending upon the waste compostlon and the
type of Uner material. For example, certain organic waste
constituents, If present In the representative waste fluid, can be
absorbed by the Uner material, thereby changing the concentration
of the chemicals 1n the waste. This change 1n waste composition
may require the waste fluid to be replaced at least monthly 1n
order to maintain representative conditions in the waste fluid.
The amount of waste fluid necessary to maintain representative
waste conditions will depend on factors such as the volume of
constituents absorbed by the specific liner material and the
concentration of the chemical constituents in the waste.
5.0 REAGENTS (Not Applicable)
6.0 SAMPLE COLLECTION, PRESERVATION, AND HANDLING
6.1 For Information on what constitutes a representative sample of the
waste fluid, refer to the following guidance document:
Permit Applicants* Guidance Manual for Hazardous Waste Land Treatment,
Storage, and Olsposal Facilities; Final Draft; Chap. 5, pp. 15-17;
Chap. 6, pp. 18-21; and Chap. 8, pp. 13-16, May 1984.
9090 - 2
Revision 0
-------
7.0 PROCEDURE
7.1 Obtain a representative sample of the waste fluid. If a waste
sample 1s received 1n more than one container, blend thoroughly. Note any
signs of stratification. If stratification exists, Uner samples must be
placed 1n each of the phases. In cases where the waste fluid 1s expected to
stratify and the phases cannot be separated, the number of Immersed samples
per exposure period can be Increased (e.g., If the waste fluid has two phases,
then 2 samples per exposure period are needed) so that test samples exposed at
each level of the waste can be tested. If the waste to be contained 1n the
land disposal unit 1s 1n solid form, generate a synthetic leachate (See Step
7.9.1).
7.2 Perform the following tests on unexposed samples of the polymeric
membrane Uner material at 23 + 2*C and 50 + 2*C (see Steps 7.9.2 and 7.9.3
below for additional tests suggested for specific circumstances). Tests for
tear resistance and tensile properties are to be performed according to the
protocols referenced in Table 1. See Figure 1 for cutting patterns for
nonrelnforced liners. Figure 2 for cutting patterns for reinforced liners, and
Figure 3 for cutting patterns for semicrystall 1 ne liners. (Table 2, at the end
of this method, gives characteristics of various polymeric Uner materials.)
1. Tear resistance, machine and transverse directions, three specimens
each direction for nonrelnforced liner materials only. See Table 1
for appropriate test method, the reconroended test speed, and the
values to be reported.
2. Puncture resistance, two specimens, FTMS 101C, Method 2065. See
Figure 1, 2, or 3, as applicable, for sample cutting patterns.
3. Tensile properties, machine and transverse directions, three tensile
specimens 1n each direction. See Table 1 for appropriate test
method, the recommended test speed, and the values to be reported.
See Figure 4 for tensile dumbbell cutting pattern dimensions for
nonrelnforced Uner samples.
4. Hardness, three specimens, Duro A (Duro D 1f Duro A reading 1s
greater than 80), ASTM D2240. The hardness specimen thickness for
Ouro A is 1/4 in., and for Ouro 0 It is 1/8 in. The specimen
dimensions are 1 1n. by 1 In.
5. Elongation at break. This test 1s to be performed only on membrane
materials that do not have a fabric or other nonelastomerlc support
as part of the Uner.
6. Modulus of elasticity, machine and transverse directions, two
specimens each direction for semi crystall 1ne Uner materials only,
ASTM D882 modified Method A (see Table 1).
7. VolatHes content, SW 870, Appendix III-0.
8. Extractables content, SW 870, Appendix III-E.
9090 - 3
Revision 0
-------
TABIC lซ PHYSICAL TCSTIRS Of fXfOSCO fCNMAJrtS IA UKl-MASTC LIQUID COffMIBlLlTl TCST
Type of compound and
conttrvct Ioa
Croft!Ia1eซ4 or wlcanlied
Theroplattlc
Seal*
cryltaMtc*
fibrtc-retnforced*
iO
O
UD
O
ToAtlle propcrtlet
hซtKซd
Type of ipedae/)
Rwfter of tpeclaent
Speed
filiMi to be reported
Hodulvt of elattUlty
Method
Type of tpซclMn
Htafcer of tpeclaent
Speed of tut
Vjlwei reported
tear retlttance
Method
Type of tpeclaen
fc*ฃer of ipedaeni
Speed of test
AST* 0412
Duabbellk
3 tn each direction
20 tpa
Itmlli UriAftli, ptl
(ionfatlon at brook, 1
Tern He tel after break, I
Strest ซt 100 and 1001
elongation, ptl
AST* D624
0Iซ C
3 in each direction
20 Ipa
Strest, ppI
ซTH DIM
Ouatbellb
3 ta tick direction
20 1pซ
TtMlli ttrtAftfc, pit
(lonfatlon it bread, t
Tentlle tet after break, f
Strett it 100 2001
elongation, ptl
ASTH 01004
o
1 Ia each directIoa
20 lpซ
Strett, ppl
ASTH 0633
UiHbbeMb
3 Ia tech direction
2 ipm
Temllt ttrett it jleld, ptl
at /leld, S
TeAtlle strength et breek, pit
(lonfatlon at break, S
Tentlle let after break, f
Strett et 100 and 2001
elongation, ptl
ASTH MR, Htd A
Strlpi 0.1-1*. ป1de end
4-1a. 1en| at M*.
Jew UfiratlM
t 1a each direction
0,2 \fm
Crettett tlope of Initial
ttreit-ttraln curve, pit
ASTH 01004
2 Ia each direction
2 lpป
Hail*** ttrett, ppl
ASTH D7S1, md I
1-1 f\ซ wide strip and
2- Ia. Jav teparatlon
3 In each direction
12 if*
lentlle et fabric break, ppl
llongatUn at fabric break, 1
Tensile at ซHIปata bna, ppl
Donation at ettlaate break. 1
Tentlle tel after break, 1
Strest at 100 and ?Q01
elongation, ppl
O Pa
a> re
r* <
(V -*
V*
*4.
LA O
ft 3
O
rt
n
a
a
co
Method
Type of fpedaen
Huafcer of iptclaent
Speed of last
Velvet reported
fMS 10IC, Method 206 S
2-U. iquire
2
20 I pa
Cage, alt
Strett, lb
floatation, 1a.
MRS 101C, Method 206$
2-In. square
2-
20 tpa
filge, all
Strut, lb
elongation, Ia.
rrns ioic, %thod 2061
2-Ia. tqvare
2
20 ipa
Ca9ซ, all
Siren, lb
Clon^etloA, Ia,
*Can be thtraoplattlc, crottllnked or wlcanlied aertrane.
6Sce Flywra 1. y
'Hot performed on this aatarlet.
dNo tear retluanca tetl It recoMondtd for fabric-reinforced theettngs Ia the 1ซwซrt ton ttJdy.
ซS**e ปi ASTH 00M, OU C.
FlUS 10K, Hathod 206S
2-Ia. t^uare
2
20
6aป, all
Strett, lb
(lon^atlon^ In,
iฃ)
00
-------
Figure 1. Suggested pattern for cutting test specimens from
nonreinforced crosslinked or thermoplastic inmersed
liner samples.
9090 - 5
Revision 0
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Figure 2. Suggested pattern for cutting test specimens from
fabric reinforced itnmersed liner saunples. Note: To
avoid edge effects, cu~ specimens 1/8 - 1/4 inch in
frcm edge of immersed sample.
9090 - 6
Revision 0
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Figure 3. Suggested pattern for cutting test specimens frcm
semicrystal 1 ine immersed liner samples. Note: To
avoid edge effects, cut specimens 1/8 - 1/4 inch
1n from edge of immersed sample.
9090 - 7
Revision 0
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G
L
D
LO
W - Width of narrow section
L - Length of narrow section
WO - Width overal1
LO - Length overall
G - Gage length
D - Distance between grips
0.25 inches
1.25 inches
0.625 inches
3.50 inches
1.00 inches
2.00 inches
Figure 4. Die for tensile dumbbell (nonreinforced
liners) having the following dimensions.
9090 - 8
Revision 0
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9. Specific gravity, three specimens, ASTM D792 Method A.
10. Ply adhesion, machine and transverse directions, two specimens each
direction for fabric reinforced Uner materials only, ASTM 0413
Machine Method, Type A 180 degree peel.
11. Hydrostatic resistance test, ASTM 0751 Method A, Procedure 1.
7.3 For each test condition, cut five pieces of the fining material of a
size to fit the sample holder, or at least 8 1n. by 10 in. The fifth sample
1s an extra sample. Inspect all samples for flaws and discard unsatisfactory
ones. Liner materials with fabric reinforcement require close Inspection to
ensure that threads of the samples are evenly spaced and straight at 90*.
Samples containing a fiber scrim support nay be flood-coated along the exposed
edges with a solution recommended by the liner manufacturer, or another
procedure should be used to prevent the scrim from being directly exposed.
The flood-coating solution will typically contain 5-15X solids dissolved 1n a
solvent. The sol ids content can be the liner formula or the base polymer.
Measure the following:
1. Gauge thickness, in. average of the four corners.
2. Mass, lb. to one-hundredth of a lb,
3. Length, 1n. average of the lengths of the two sides plus the
length measured through the liner center.
4. Width, In. average of the widths of the two ends plus the width
measured through the liner center.
NOTE: Do not cut these liner samples Into the test specimen shapes shown
1n Figure 1, 2, or 3 at this time. Test specimens will be cut as
specified 1n 7.7, after exposure to the waste fluid.
7.4 Label the Uner samples (e.g., notch or use metal staples to
Identify the sample) and hang In the waste fluid by a wire hanger or a weight.
Different liner materials should be Immersed 1n separate tanks to avoid
exchange of plastlclzers and soluble constituents when plastlclzed membranes
are being tested. Expose the Uner samples to the stirred waste fluid held at
room temperature and at 50 + 2*C.
7.5 At the end of 30, 60, 90, and 120 days of exposure, remove one liner
sample from each test condition to determine the membrane's physical
properties (see Steps 7.6 and 7.7). Allow the Uner sample to cool 1n the
waste fluid until the waste fluid has a stable room temperature. Wipe off as
much waste as possible and rinse briefly with water. Place wet sample 1n a
labeled polyethylene bag or aluminum' foil to prevent the sample from drying
out. The Uner sample should be tested as soon as possible after removal from
the waste fluid at room temperature, but 1n no case later than 24 hr after
removal.
9090 - 9
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7.6 To test the Immersed sample, wipe off any remaining waste and rinse
with delonlzed water. Blot sample dry and measure the following as 1n Step
7.3:
1. Gauge thickness, 1n.
2. Mass, lb.
3. Length, In.
4. Width, In.
7.7 Perform the following tests on the exposed samples (see Steps 7.9.2
and 7.9.3 below for additional tests suggested for specific circumstances).
Tests for tear resistance and tensile properties are to be performed according
to the protocols referenced 1n Table 1. 01e-cut test specimens following
suggested cutting patterns. See Figure 1 for cutting patterns for
nonrelnforced liners, Figure 2 for cutting patterns for reinforced liners, and
Figure 3 for semi crystal line liners.
1. Tear resistance, machine and transverse directions, three specimens
each direction for materials without fabric reinforcement. S$e Table 1 for
appropriate test method, the recotnnended test specimen and speed of test, and
the values to be reported.
2. Puncture resistance, two specimens, FTMS 101C, Method 2065. See
Figure 1, 2, or 3, as applicable, for sample cutting patterns.
3. Tensile properties, machine and transverse directions, three
specimens each direction. See Table 1 for appropriate test method, the
reconmended test specimen and speed of test, and the values to be reported.
See Figure 4 for tensile dumbbell cutting pattern dimensions for nonrelnforced
liner samples.
4. Hardness, three specimens, Duro A (Duro D If Duro A reading 1s
greater than 80), ASTM 2240. The hardness specimen thickness for Ouro A Is
1/4 1n., and for Ouro 0 Is 1/8 1n. The specimen dimensions are 1 1n. by 1 In.
5. Elongation at break. This test Is to be performed only on membrane
materials that do not have a fabric or other nonelastomerlc support as part of
the Uner.
6. Modulus of elasticity, machine and transverse directions, two
specimens each direction for semi crystalline Hner materials only, ASTM 0882
modified Method A (see Table 1).
7. Volatlles content, SW 870, Appendix III-D.
8. Extractables content, SW 870, Appendix III-E.
9090 - 10
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9. Ply adhesion, machine and transverse directions, two specimens each
direction for fabric reinforced Uner materials only, ASTM 0413 Machine
Method, Type A 180 degree peel.
10. Hydrostatic resistance test, ASTM 0751 Method A, Procedure 1.
7.8 Results and reporting:
7.8.1 Plot the curve for each property over the time period 0 to
120 days and display the spread 1n data points.
7.8.Z Report all raw, tabulated, and plotted data. Recotnnended
methods for collecting and presenting information are described in the
documents listed under Step 6.1 and 1n related agency guidance manuals.
7.8.3 Summarize the raw test results as follows:
1. Percent change 1n thickness.
2. Percent change 1n mass.
3. Percent change in area (provide length and width dimensions).
4. Percent retention of physical properties.
5. Change, 1n points, of hardness reading.
6. The-nodulus of elasticity calculated in pounds-force per
square Inch.
7. Percent volatlles of unexposed and exposed Uner material.
8. Percent extractables of unexposed and exposed Uner material.
9. The adhesion value, determined 1n accordance with ASTM 0413,
Section 12.2.
10. The pressure and time elapsed at the first appearance of
water through the flexible membrane Uner for the hydrostatic
resistance test.
7.9 The following additional procedures are suggested in specific
situations:
7.9.1 For the generation of a synthetic leachate, the Agency
suggests the use of the Toxicity Characteristic Leaching Procedure (TCLP;
that was proposed 1n the Federal Register on June 13, 1986, Vol. 51, No.
114, p. 21685.
7.9.2 For serai crystal line membrane liners, the Agency suggests the
determination of the potential for environmental stress cracking. The
9090 - 11
Revision 0
-------
test that can be used to make this detenalnation 1s either ASTM D1693 or
the National Bureau of Standards Constant Tensile Load. The evaluation
of the results should be provided by an expert in this field.
7.9.3 For field seams, the Agency suggests the determination of
seam strength In shear and peel nodes. To determine seam strength 1n
peel mode, the test ASTM 0413 can be used. To determine seam strength 1n
shear node for nonrelnforced FMLs, the test ASTM 03083 can be used, and
for reinforced FMLs, the test ASTM D751, Grab Method, can be used at a
speed of 12 In. per n1n. The evaluation of the results should be
provided by an expert In this field.
8.0 QUALITY CONTROL
8.1 Oeterraine the mechanical properties of identical nonimmersed and
immersed liner samples 1n accordance with the standard methods for the
specific physical property test. Conduct mechanical property tests on
nonimmersed and immersed Uner samples prepared from the same sample or lot of
material 1n the same manner and run under identical conditions. Test liner
samples 1nmed1ately after they are removed from the room temperature test
solution.
9.0 METHOD PERFORMANCE
9.1 No data provided.
10.0 REFERENCES
10.1 None required.
9090 - 12
Revision 0
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TABLE 2. POLYMERS USED IN FLEXIBLE MEMBRANE LINERS
Thermoplastic Materials (TP)
CPE (Chlorinated polyethylene)3
A family of polymers produced by a chemical reaction of chlorine on
polyethylene. The resulting thermoplastic elastomers contain 25 to 45X
chlorine by weight and 0 to 25X crystal Unity.
CSPE (Chlorosulfonated polyethylene)4
A family of polymers that are produced by the reaction of polyethylene
with chlorine and sulfur dioxide, usually containing 25 to 432 chlorine
and 1.0 to 1.4X sulfur. Chlorosulfonated polyethylene 1s also known as
hypalon.
EIA (Ethylene Interpolymer alloy)a
A blend of EVA and polyvinyl chloride resulting 1n -a thermoplastic
elastomer.
PVC (Polyvinyl chloride)4
A synthetic thermoplastic polymer made by polymerizing vinyl chloride
monomer or vinyl chloride/vinyl acetate monomers. Normally rigid and
containing 50X of plastlclzers.
PVC-CPE (Polyvinyl chloride - chlorinated polyethylene alloy)4
A blend of polyvinyl chloride and chlorinated polyethylene.
TN-PVC (Thermoplastic nltrlle-polyvlnyl choloride)4
An alloy of thermoplastic unvulcanlzed nltrlle rubber and polyvinyl
chloride.
Vulcanized Materials (XL)
Butyl rubber4
A synthetic rubber based on Isobutylene and a small amount of isoprehe to
provide sites for vulcanization.
aAlso supplied reinforced with fabric.
9090 - 13
Revision 0
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TABLE 2. (Continued)
EPOM (Ethylene propylene dlene monomer)aปb
A synthetic elastomer based on ethylene, propylene, and a small amount of
nonconjugated dlene to provide sites for vulcanization.
CM (Cross-linked chlorinated polyethylene)
No definition available by EPA.
CO, ECO (Eplcttlorohydrln polymers)8
Synthetic rubber, Including two eplchlorohydrln-based elastomers that are
saturated, h1gh-nolecular-we1ght aliphatic polyethers with chloromethyl
side chains. The two types include homopolymer (CO) and a copolymer of
eplchlorohydrln and ethylene oxide (ECO).
CR (Polychloroprene)a
Generic name for a synthetic rubber based primarily on chlorobutadlene.
Polychloroprene 1s also known as neoprene.
Semi crystal!1nc Materials (CX)
HOPE - (High-density polyethylene)
A polymer prepared by the low-pressure polymerization of ethylene as
the principal nonomer.
HOPE - A (High-density polyethylene/rubber alloy)
A blend of h1gh-dens1ty polyethylene and rubber.
LLDPE (Liner low-density polyethylene)
A low-density polyethylene produced by the copolymerlzatlon of ethylene
with various alpha olefins 1n the presence of suitable catalysts.
PEL (Polyester elastomer)
A segmented thermoplastic copalyester elastomer containing recurring
long-chain ester units derived from dlcarboxyllc acids and long-chain
glycols and short-chain ester units derived from dlcarboxyllc adds and
low-molecular-we1ght dlols.
aAlso supplied reinforced with fabric.
^Also supplied as a thermoplastic.
9090 - 14
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TABLE 2. (Continued)
PE-EP-A (Polyethylene ethylene/propylene alloy)
A blend of polyethylene and ethylene and propylene polymer resulting In a
thermoplastic elastomer.
T-EPON (Thermoplastic EPDH)
An ethylene-propylene dlene nonomer blend resulting 1n a thermoplastic
elastomer.
9090 - 15
Revision 0
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-------
ATTACHMENT C
Observations and Tests for the Construction Quality Assurance and
-------
OBSERVATIONS AND TESTS FOR THE CONSTRUCTION QUALITY ASSURANCE
AND QUALITY CONTROL OF HAZARDOUS WASTE DISPOSAL FACILITIES
This appendix lists observations that should be made and tests that
should be performed for the construction quality assurance of the following
components of hazardous waste disposal facilities:
- Foundations.
- Embankments.
- Low-permeabi1ity soil liner.
- Leachate collection system.
Methods for testing FMLs are presented and discussed in Chapter 4. This
appendix is based on Appendix A of the EPA Technical Guidance Oocument,
"Construction .Quality Assurance for Hazardous Waste Land Disposal Facilities"
(Northeim and Truesdale, 1986). Table M-l lists the observations and tests
by component.
REFERENCES
Anderson, D. C., J. 0. Sai, and A. Gill, 1984. Surface Impoundment Soil
Liners. Draft Report (unpublished) to U.S. Environmental Protection
Agency by K. W. Brown and Associates Inc., EPA Contract #68-03-2943.
AASHTO. 1986. Standard Specifications. American Association State Highway
and Transportation Officials. Part II Tests, 14th Edition, Washington,
D.C.:
AASHTO 217-86. "Determination of Moisture in Soils by Means of a
Calcium Carbide Gas Pressure Moisture Tester."
ASTM. Annual Book of ASTM Standards. Issued annually in several parts.
American Society for Testing and Materials, Philadelphia, PA:
C31-85. "Methods of Making and Curing Concrete Test Specimens in the
Field," Section 04.02.
-------
C138-81.
C143-78.
r 79_QO
V J, / C KJC.
C231-82.
"Test Method for Unit Weight, Yield, and Air Content (Gravi-
metric) of Concrete," Section 04.02.
"Test Method for Slump of Portland Cement Concrete," Section
04.02.
"Metftod of Sampling Freshly Mixed Concrete," Section 04.02.
"Test Method for Air Content of Freshly Mixed Concrete by the
Pressure Method," Section 04.02.
D422-63(1972). "Method for Particle-Size Analysis of Soils," Section
04.08.
0559-82. "Methods for Wetting-and-Orying Tests of Compacted Soil-Cement
Mixtures," Section 04.08.
0560-82. "Methods for Freezing-and-Thawing Tests of Compacted Soil -
Cement Mixtures," Section 04.08.
D698-78. "Test Methods for Moisture-Density Relations of Soils and
Soi1-Aggregate Mixtures, Using 5.5-1b (2.49-kg) Rammer and
12-in. (304.8-mm) Drop," Section 04.08.
01556-82. "Test Method for Density of Soil in Place by the Sand-Cone
Method," Section 04.08.
D1557-78. "Test Methods for Moisture-Density Relations of Soils and
Soi1-Aggregate Mixtures Using 10-1b (4.54-kg) Rammer and
18-in. (457-mm) Drop," Section 04.08.
D1633-84. "Test Method for Compressive Strength of Molded Soil-Cement
Cylinders," Section 04.08.
02165-78(1983). "Test Method for pH of Aqueous Extracts of Wool and
Similar Animal Fibers," Section 07.02.
D2166-85. "Test Method for Unconfined Compressive Strength of Cohesive
Soil," Section 04.08.
D2216-80. "Method for Laboratory Determination of Water (Moisture)
Content of Soil, Rock, and Soi1-Aggregate Mixtures," Section
04.08.
02487-85. "Classification of Soils for Engineering Purposes,"
Section 04.08.
D2.488-84. "Practice for Description and Identification of Soils
(Visual-Manual Procedure)," Section 04.08.
02573-72(1978). "Method for Field Vane Shear Test in Cohesive Soil,"
Section 04.08.
-------
D2850-82. "Test Method for Unconsolidated, Undrained Strength of
Cohesive Soils in Triaxial Compression," Section 04.08.
D2922-81. "Test Methods for Density of Soil and Soi1-Aggregate in Place
by Nuclear Methods (Shallow Depth)Section 04.08.
D2937-83. "Test Method for Density of Soil in Place by the Drive-
Cylinder Method," Section 04.08.
D3017-78. "Test Method for Moisture Content of Soil and Soil-Aggregate
in Place by Nuclear Methods (Shallow Depth)," Section 04.08.
D3441-79. "Method for Deep, Quasi-Static, Cone and Friction-Cone
Penetration Tests of Soil," Section 04.08.
D4318-84. "Test Method for Liquid Limit, Plastic Limit, and Plasticity
Index of Soils," Section 04.08.
Chamberlin, E. J. 1981. Comparative Evaluation of Frost--Susceptibi1ity
Tests. Transportation Research Record 809. U.S. Department of Trans-
portation, Washington, D.C.
Daniel, D. E., S. J. Trautwen, S. S. Boynton, and D. E. Foreman. 1984.
Permeability Testing with Flexible-Wall Permeameters. Geotechnical
Testing Journal 7(3):113-122.
Daniel, D. E., D. C. Anderson, and S. S. Boynton. 1985. Fixed-Wall Versus
Flexible-Wall Permeameters. In: Hydraulic Barriers in Soil and Rock.
A. I. Johnson, R. K. Frobel, N. J. Cavalli, and C. B. Pettersson, eds.
ASTM STP 874. American Society for Testing and Materials, Philadephia,
PA. pp 107-23.
Day, S. D., and D. E. Daniel. 1985. Field Permeability Test for Clay
Liners. In: Hydraulic Barriers in Soil and Rock. A. I. Johnson, R. K.
Frobel, N. J. Cavalli, and C. B. Pettersson, eds. ASTM STP 874.
American Society for Testing and Materials, Philadephia, PA. pp 276-87.
EPA. 1986. Test Methods for Evaluating Solid Waste. Vol 1A: Laboratory
Manual, Physical Chemical Methods. 3rd ed. SW-846. U.S. Environmental
Protection Agency, Washington, D.C.
Holtz, W. G. 1965. Volume Change. In: Methods of Soil Analysis. Part 1.
C. E. Black, ed. American Society of Agronomy, Madison, WI.
Horslev, M. J. 1943. Pocket-Size Piston Samplers and Compression Test
Apparatus. USAE Waterways Experiment Station. Vicksburg, MS.
Horz, R. C. 1984. Geotextiles for Drainage and Erosion Control at Hazardous
Waste Landfills (draft). Prepared by the U.S. Waterways Experiment
Station, Vicksburg, MS, for U.S. Environmental Protection Agency.
Interagency Agreement No. AD-96-F-1-400-1.
-------
Lanz, L. J. 1968. Dimensional Analysis Comparison of Measurements Obtained
in Clay with Torsional Shear Instruments. Master of Science Thesis,
Mississippi State University, Starkville, MS.
Northeim, C. M., and R. S. Truesdale. 1986. Technical Guidance Document:
Construction Quality Assurance for Hazardous Waste Land Disposal Facil-
ities. EPA 530-SW-86-031. OSWER Policy Directive No. 9472.003. U.S.
Environmental Protection Agency, Washington, D.C. 88 pp.
Spigolon, S. J., and M. F. Kelley. 1984. Geotechnical Assurance of Con-
struction of Disposal Facilities. Interagency Agreement No. AD-96-F-2-
A077. EPA 600/2-84-040. NTIS PB 84-155225. U.S. Environmental
Protection Agency, Cincinnati, OH.
U.S. Army. 1971. Materials Testing. TM-5-530, Washington, D.C.
U.S. Army. 1977. Construction Control for Earth and Rockfill Dams. EM
1110-2-1911. Washington, D.C.
-------
TABLE M-l. OBSERVATIONS AND TESTS FOR THE CONSTRUCTION QUALITY ASSURANCE
AND QUALITY CONTROL OF HAZARDOUS WASTE DISPOSAL FACILITIES
Facility component
Factors to be inspected
Inspection methods
Test
method reference
Foundation
Removal of unsuitable materials
Observation
NA
Proof rolling of subgrade
Observation
NA
Filling of fissures or voids
Observation
NA
Compaction of soil backfill
(See low-permeab1Hty soil
Uner component)
i * t
Surface finishing/compaction
Observation
NA
Sterilization
Supplier's certification and
observation
NA
Slope
Surveying
NA
Depth of excavation
Surveylng
NA
Seepage
Observati on
NA
Soil type (index properties)
Visual-manual procedure
Part1cle-s1ze analysis
Atterberg limits
Soil classification
V
ASTM D2488
ASTM U422
ASTM D4318
ASTM D2487
Cohesive soil consistency
(field)
Penetration tests
Field vane shear test
Hand penetrometer
Handheld torvane
Field expedient unconflned
compression
ASTM D3441
ASTM D2573
Horslev, 1943
Lanz, 1968
TM 5-530 (U.S.
of Army, 1971)
-------
TABLE M-l (CONTINUED)
Facility component
Factors to be inspected
Inspection methods
Test
method reference
Embankments
Low-permeability
soil Uner
Strength (laboratory)
Dike slopes
Dike dimensions
Compacted soil
Drainage system
Erosion control measures
Coverage
Thickness
Clod size
Tying together of lifts
Slope
Installation of protective cover
Soil type (Index properties)
Unconflned compressive
strength
Tr1ax1al compression
Surveying
Surveying; observations
(See foundation component)
(See leachate collection
system component)
(See cover system component)
Observation
Surveying; measurement
Observation
Observation
Surveying
Observation
V1 sual-manual procedure
Particle-size analysis
Atterberg limits
Soil classification
ASTM D2166
ASTM D2850
NA
NA
NA
NA
NA
NA
* t ซ
NA
ASTM D2488
ASTM D422
ASTM D4318
ASTM D2487
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TABLE M-l (CONTINUED)
Facility component
Factors to be inspected
Inspection methods
Test
method reference
Moisture content
In-place density
Moisture-density relations
Strength (laboratory)
Cohesive soil consistency
(field)
Permeability (laboratory)
Oven-dry method
Nuclear method
Calcium carbide (speedy)
Frying pan (alcohol or
gas burner)
Nuclear methods
Sand cone
Rubber balloon
Drive cylinder
Standard proctor
Modified proctor
Unconflned compressive
strength
Triaxial compression
Unconfined compressive
strength for soil cement
Penetration tests
Field vane shear test
Hand penetrometer
Handheld torvane
Field expedient unconfined
compression
Flexible wall
ASTM D2166
ASTM D3017
AASHTO T217
Spigolon & Kelley,
1984
ASTM D2922
ASTM D1556
ASTM D2167
ASTM D2937
ASTM D698
ASTM D1557
ASTM D2166
ASTM D2850
ASTM D1633
ASTM D3441
ASTM D2573
Horslev, 1943
Lanz, 1968
TM 5-530 (U.S.
Dept. of Army,
1971)
Daniel et al, 1984
Daniel et al, 1985
SW-846, Method
9100 (EPA, 1986)
-------
TABLE M-l
Facility component Factors to be Inspected
Permeability (field)
Susceptibility to frost
damage
Volume change
Leachate collec-
tion system:
- Granular drain- Thickness
age and fil-
ter layers Coverage
Soil type
Density
Permeability
(laboratory)
(CONTINUED)
Inspection methods
Test
method reference
Large diameter single-
ring 1nf1ltrometer
Sa1-Anderson inflltrometer
Susceptibility classifi-
cation
Soil-cement freeze-thaw test
Consolldometer (undisturbed
or remolded sample)
Soil-cement wet-dry test
Soil-cement freeze-thaw test
Day and Daniel,
1985
Anderson et al,
1984
Chamberlin, 1981
ASTM D560
Holtz, 1965
ASTM D559
ASTM D560
Surveying; measurement
Observation
Visual-manual procedure
Particle-size analysis
Soil classification
Nuclear methods
Sand cone
Rubber balloon
NA
NA
ASTM D2488
ASTM D422
ASTM D2487
ASTM D2922
ASTM D1556
ASTM D2167
Constant head
ASTM D2434
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TABLE M-l
(CONTINUED)
Facility component
Factors to be inspected
Inspection methods
Test
method reference
- Synthetic
drainage
and filter
layers
Material type
Handling and storage
Manufacturer's certifi-
cation
Observation
NA
NA
Coverage
Observation
NA
Overlap
Observation
NA
Temporary anchoring
Observation
NA
Folds and wrinkles
Observation
NA
Geotextile properties
Tensile strength
Puncture or burst
resistance
Tear resistance
Flexibility
Outdoor weatherabl1ity
Short-term chemical
resistance
Fabric permeability
Percent open area
Horz, 1984
Hor2, 1984
Horz, 1984
Horz, 1984
Horz, 1984
Horz, 1984
Horz, 1984
Horz, 1984
- Pipes
Material type
Manufacturer's certification
NA
Handling and storage
Observation
NA
-------
TABLE M-l (CONTINUED)
Test
Facility component Factors to be inspected Inspection methods method reference
Location
Layout
Orientation of perforations
Surveying
Surveying
Observation
NA
NA
NA
Cast-in-place con-
crete structures
Sampling
Consistency
Sampling fresh concrete
Slump of portland cement
ASTM CI72
ASTM C143
Compressive strength
Making, curing, and testing
concrete specimens
ASTM C31
Ai r content
Pressure method
ASTM C231
Unit weight, yield, and
ai r content
Gravimetric method
ASTM CI38
Form work Inspection
Observation
NA
Electrical and
mechanical
equi pment
Equipment type
Material type
Manufacturer's certification
Manufacturer's certification
NA
NA
Operation
As per manufacturer's
Instructions
NA
Electrical connections
As per manufacturer's
instructions
NA
Insulation
As per manufacturer's
Instructions
NA
Grounding
As per manufacturer's
instructions
NA
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-------
ATTACHMENT D
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28828
Federal Register / Vol 57. No. 124 / Friday, June 28, 1992 / Rules and Regulations
These amendments correct all of the
deficiencies identified in the Nashville/
Davidson County portion of the
Tennessee SIP except the recordkeeping
requirements. This remaining deficiency
will be acted upon in a separate notice.
Therefore, the requirements of section
182(a)(2)(A) for Reasonably Available
Control Technology have been met for
the Nashville/Davidson County portion
of the Tennessee SOP.
Final Action
This action is being taken without
prior proposal because the changes are
noncontroversial and EPA anticipates
no significant comments on them. The
public should be advised that this action
will be effective August 25,1992.
However, if notice is received within 30
days that someone wishes to submit
adverse or critical comments, this action
will be withdrawn and two subsequent
notices will be published before the
effective date. One notice will withdraw
the final action and another will begin a
new rulemaking by announcing a
proposal of the action and establishing a
comment period.
Under section 307(b)(1) of the Act,
petitions for judicial review of this
action must be filed in the United States
Court of Appeals for the appropriate
circuit by August 25,1992. Filing a
petition for reconsideration by the
Administrator of this final rule does not
affect the finality of this rule for the
purposes of judicial review nor does it
extend the time within which a petition
for judicial review may be filed, and
shall not postpone the effectiveness of
such rule of action. This action may not
be challenged later in proceedings to
enforce its requirements [See 307(b)(2)].
This action has been classified as a
Table 2 action .by the Regional
Administrator under the procedures
published in the Federal Register on
January 19.1989 (54 FR 2214-2225). On
January 6.1989, the Office of
Management and Budget waived Table 2
and 3 SIP revisions (54 FR 2222) from the
requirements of section 3 *jฃ .Executive
Order 12291 for two years. EPA has
submitted a request for a permanent
waiver for Table 2 and Table 3 SIP
revisions. OMB has agreed to continue
the temporary waiver until such time as
it rules on EPA's request.
Nothing in this action shall be
construed as permitting or allowing or
establishing a precedent for any future
request for a revision to any State
Implementation Plan. Each.request for
revision to the State Implementation
Plan shall be considered separately in
light of specific technical, economic and
environmental factors and in relation to
relevant statutory and regulatory
requirements.
List of Subjects in 40 CFR Part 52
Air pollution control. Hydrocarbons,
Incorporation by reference.
Intergovernmental relations. Ozone.
Reporting and recordkeeping
requirements.
Dated: May 21,1992.
Patrick M. Tobin,
Acting Regional Administrator.
Part 52 of chapter I. title 40. Code of
Federal Regulations, is amended as
follows:
PART 52-{ AMENDED]
1. The authority citation for part 52
continues to read as follows:
Authority: 42 U.S.C. 7401-7671 q.
Subpart RRTennessee
2. Section 52.2220 is amended by
adding paragraph (c)(105) to read as
follows:
S 52J220 Identification of plan.
ซ * ซ
(c) * *
(105) Amendments to the Nashville/
Davidson County portion of Tennessee's
SIP, Regulation No. 7Regulation for
Control of Volatile Organic Compounds
submitted on July 3,1991, October 4,
1991, and January 2.1992.
(j) Incorporation by reference.
(A) Regulation No. 7Regulation for
the Control of Volatile Organic
Compounds, effective December 10,
1991.
(ii) Other material.
(A) Letter of July 3.1991, from the
Metropolitan Health Department for
Nashville/Davidson County.
(B) Letter of October 4,1991, from the
Metropolitan Health Department for
Nashville/Davidson County.
(C) Letter of January 2,1991. from the
Metropolitan Health Department for
Nashville/Davidson County.
3. Section 52.2225 is amended by
revising paragraphs (a) introductory text
and (a)(1) to read as follows:
{ 52.2225 VOC rule deficiency correction.
(a) Revisions to the sections 7-3, 7-13,
and 7-24 of the Tennessee regulations
are approved. These amendments are in
response to the Clean Air Act section
182(a)(2)(A) requirement to submit
RACT rules correcting deficiencies in
the existing SIP in accordance with
EPA's pre-amendment guidance. These
deficiencies were first noted in a letter
from Greer Tidwell, the EPA Region IV
Administrator, to Governor McWherter
on May 26,1988, and clarified in a letter
dated June 10,1988, from Winston
Smith, EPA Region IV Air Division
Director, to Paul Bontrager, Director of
the Air Pollution Control Division of ihe
Metropolitan Health Department for
Nashville/Davidson County, and we:e
further identified in EPA guidance
including the Blue Book and the
proposed Post-87 policy. The following
deficiency in the Tennessee Regulations,
however, has not been corrected.
(1) Section 7-25, "Recordkeeping and
Reporting Requirements" Nashville/
Davidson County committed in a letter
dated May 7,1991, to include a separate
provision that requires records to be
maintained for at least two years. This
additional provision, which is scheduled
for a July 15,1992, public hearing, will be
submitted to EPA shortly after lhat cue
and will be acted upon separately.
ป
[FR Doc. 92-14665 Filed ft-25-92. 8 ->5 c.- |
BXJJttQ C00C t560-50-M
(EPA/OS W-FR-92-4146-61
40 CFR Parts 257 and 256
9oHd Waste Disposal Facility Criteria.
AGENCY:Environmental Pro:?-
Agency (EPA)
ACTION: Final rule; corrections.
SUMMARY: EPA iB correcting error s i
the preamble and rule language for,L ?
Solid Waste Disposal Facility Crtera
for municipal solid waste landfills - Y.at
appeared in the Federal Register on
October 9,1991 (56 FR 50978). This
correction notice will resolve the r.:r.c-r
misunderstandings that the regulated
community has called to the Agency's
attention. The Agency also is c!ar.f\,;r.g
its interpretation of the final cover
requirements for the Criteria.
FOR FURTHER INFORMATION CONTACT.
Mr. Paul Cassidy at (202) 260-1662 or
Mr. Allen Geswein at (202) C60-4667.
SUPPLEMENTARY INFORMATION: On
October 9,1991r EPA promulgated e e
under Subtitle D of the Resource
Conservation and Recovery Act ar.d
section 405 of the Clean Water Act
pertaining to the disposal of solid wcs'e
and sewage sludge in municipal solid
waste landfills (MSWLFs) (56 FR 50978
(October 9,1991)). The preamble and
rule language contained minor editondl
and typographical errors that EPA is
correcting in this notice. The Agency
also is clarifying its interpretation of ,
that part of die MSWLF rule concerning
the design of a final cover under
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Federal Register / Vol. S7, No. 124 / Friday, June 26, 1992 / Rules and Regulations
28627
The MSWLF rule requires that
owners/operators "must install a final
cover system that is designed to
minimize infiltration and erosion" (40
CFR 258.60(a). Aa specified in the rule,
the final cover system must be
comprised of an infiltration layer that is
"a minimum of 18 inches of e&irthen
material that has a permeability less
than or equal to the permeability of any
bottom liner Bystem or natural subsoils
present, or a permeability no greater
than 1 x 10 "6 cm/sec whichever is less"
and an erosion layer that must consist of
a "minimum of B Inches of earthen
material that is capable of sustaining
native plant growth" (40 CFR 258.60 (a)
(1) and (2)).
EPA established the requirement for a
final cover infiltration layer, which
includes a permeability standard, to
prevent the "bathtub effect" from
occurring. The "bathtub effect" occurs
when a landfill fills up with liquids
because the infiltration layer of the final
cover is more permeable than the
bottom liner system or natural subsoils
present Such an effect greatly increases
the potential for the formation and
migration of leachate (56 FR 50978,51095
(October 9,1991}).
Some members of the public have
questioned the applicability of the
permeability standard contained in
9 258.6(a)(1) to a MSWLF that has a
synthetic membrane on the bottom of
the landfill. They have interpreted
S 258.60(a)(1) to suggest that only 18
inches of earthen material is required as
an infiltration layer even when the
landfill has a synthetic membrane on the
bottom.
Such an interpretation of the
permeability standard contained in
5 258.60(a)(1) is incorrect. EPA intended,
and has always interpreted, the
language in this section to be a
performance standard that requires the
permeability of the final cover be less
than or equal to that of the bottom liner
system or natural subsoils present,
whichever is less. To achieve this, it
requires as a minimum the use of 16
inches of earthen material. While this
standard does not explicitly require the
use of a synthetic membrane in the final
cover, the Agency anticipates that if a
MSWLF has a synthetic membrane in
the bottom of the unit, then the
infiltration layer in the final cover will,
in all likelihood given today's
technologies, include a synthetic
membrane as part of the final cover.
This is so because it generally is not
currently possible to have an earthen
material infiltration layer as part of the
final cover that has a permeability of
less than or equal to the permeability of
a synthetic membrane. The Agency
c 11118 requirement because if
a MSWLF were constructed with a
bottom synthetic membrane, but
covered only with 18 inches of earthen
material as the infiltration layer, the
bathtub effect would likely occur, and
the Agency's overriding reason for
establishing the permeability standard
in S 258.60(a)(1) would be negated.
If a synthetic membrane needs to be
included in the final cover, the Agency
recommends that a minimum thickness
of 20 mils be used. (In the case of high
density polyethylene (HDPE), a
minimum 60 mils is necessary to ensure
proper seaming of the synthetic
membrane.) The synthetic portion of the
final cover does not have to be the same
type or thickness as the membrane used
in the bottom of the facility since the
performance standard is concerned with
the permeability standard.
This interpretation is not new. It is
clear from reviewing the Regulatory
Impact Analysis (RIA) and the preamble
to the final rule (see 56 FR 50987) that
the Agency had always interpreted this
rule language to mean if there was a
synthetic membrane in the bottom of a
MSWLF, a synthetic membrane would,
given today's technologies, be necessary
as part of the final cover. The Agency
has recently issued an Environmental
Fact Sheet (EPA/530-SW-91-084. March
1992) that further highlights this
interpretation.
The following are illustrations of the
correct interpretation of this rule
language. These illustrations present
typical designs of MSWLFs and the
corresponding correct final cover as
required under { 258.60(a).
MSWLF oestgn
I
Minimum final cover
No liner (m-situ soils)..
Recompacted 1 <
10 ~f cm/sec. sorf
liner.
Convosite l*oer (80
ml synthebc over
3 foot
recompacted 1 <
10 sod liner)
Minimum infiltration layer of
18-tocnes of 1 k 10
cm/sec earthen material
ovenam by a minimum 6-
mch erosion layer
Minimum infiltration layer of
18-^ncnes of 1 <10 "
cm/sec earthen material
overlain by a minimum 6-
mch erosjon layer
Minimum infiltration layer of
18-mches of 1 < 10*'
cm/sec earthen material
ovenam by a synthetic
liner (Agency recommends
minimum 20 mils, il HOPE
60 mils) overlain by mini-
mum 6-tnch erosion layer
To correct any misunderstanding
regarding the permeability standard of
the final cover design, the Agency is
today revising the language of
5 258.60(a) to provide further
clarification. This revision is intended to
eliminate any confusion regarding the
correct interpretation of this rule
language. This clarifying language does
not remove any of the flexibility in
8 256.60(b) regarding alternative final
cover designs approved by the Director
of a State/Tribal program that has been
deemed adequate by EPA.
The other technical corrections being
made today involve editorial changes,
typographical changes, and minor
corrections to dates, and are necessary
to make the Code of Federal Regulations
accurate.
Dated. |une IS. 1992.
Don R. day.
Assistant Administrator.
The following corrections are made in
FRLr^011-9, the Solid Waste Disposal
Facility Criteria; final rule published in
the Federal Register on October 9, 1901
(56 FR 50978):
1. On page 51001Figure 1. third
rectangle in the right side of the flow
chart, change "You must comply only
with the final cover requirements of
$ 258.60(a)(2)" to read "You must
comply only with the final co\er
requirements of 5 258.60(a)
2. On page 51010Figure 5. second
decision diamond on the left side of the
flow chart change "Are All Appendix II
Constituents Below Background' !o nvid
"Are All Appendix II Constituents At Or
Below Background".
3. On page 51012, third column. 1 jsi
paragraph, fourth sentence, change
"Figure 1 indicates, for example, that .f
your MSWLF will not receive waste
after the effective date, only the final
cover requirements of ง 253.60(a)(2) will
apply" to read "Figure 1 indicates, for
example, that If your MSWLF will not
receive waste after the effective date,
only the final cover requirements of
S 258.60(a) will apply".
4. On page 51018, first column. I'.ne 10
of the definition of "Municipal solid
waste landfill unit." revise "solid wjste.
nonhazardous sludge, small" to read,
"solid waste, nonhazardous sludy>2.
conditionally exempt small".
PART 258{AMENDED]
ง258.14 [Amended]
5. On page 51019, second column,
lines 6 and 7 of 5 258.14(b)(1). revise the
phrase "paragraph (g) of this section" to
read "(g)".
5 258.25 [Amended]
6. On page 51021. first column. rc\ lse
the title "8 258.25 Run-on/run-off control
systems" to read "5 258.26 Run-on/run-
-------
Federal Register / Vol. No. 134 f Friday, Jane 26, 1992 / Roles and Regulations
S2ML5A UmmMI
7. On pege 51022, second cohnnn,
{ 25150 Applicability, test line of
paragraph (c)(1), revise "by October 9,
1996c" to read "by Octobe*9r 1994;".
J 258^0 [Amended]
8. On page 5102a, second
5 258.00 Closure criteria paragraph (a) is
revised to read as follows:
(a) Owners or operators of all MSWLF
units must install a final cover system
that is designed to minimize infiltration
and erosion. The final cover system
must be designed and constructed to:
(1) Have a permeability less than or
equal to the permeability of any bottom
liner system or natural subaoils present,
or a permeability no greater than
iXlCT'cm/sec, whichever is less, and
(2) Minimize infiltration through the
closed MSWLF by the ซse of an
infiltration layer that cootflim a
minimum 18-inches of earthen material,
and
(3} Minimize erosion of the final covet
by the use of an erosion layer that
contains a minimum 6-inches of earthen
material that is capable of sustaining
native plant growth.
9. On page 51028. third column. line
15, paragraph (h)(1) revise "in paragraph
(a)(IJ of this section, antf* to read
"paragraphs (a)(1) and (a)(2) of this
section, and".
10. On page 51028, third cohnnn.
5 258.00 Closure criteria, paragraph
(b)(2) revise "specified in paragraph
(a)(2) of this section." to read "specified
in paragraph (a)(3) of this section."
11. On page 51028, third cohnnn,
S 258.60 Closure criteria, paragraph (c),
revise "all MSWLF mite at any point
daring its active life" to read "all
MSWLF units at any point during their
active He".
S 25841 [Amwutedl
12. On page 51029. second column.
ง 258.61 Post-closure care requirements,
paragraph (a)(2), revise "ง 258.40. The
Director of an approved" to read
"5 25a.40, if applicable. The Director of
an approved".
13. On page 51029, second and third
columns, ง 258.81 Post closure care
requirements, paragraph fd). revise
"October 9,1991," to read "October 9,
1993,".
} 258.71 [Amended]
14. On page 51029, third column,
S 258.71 Financial assurance for closure,
lines 4 and 5 of paragraph (a), revise
"the largest area of all MSWLF unit
ever'' to read "the largest area of all
MSWLF nnita ever".
|FR Doc 9215137 PtM 0-25-02 *45 ami
BILLING COOt SMO-M-M
40 CFR Part 290
[FRL-414A-6)
Hazardous Waste Management
System: Land Disposal Restrictions
AGCMCYt Environmental Protection
Agency (EPA).
ACTION: Notice to approve storage of
lead-bearing hazardous materials case-
by-case capacity variance.
SUMMARY: In the final rule establishing
land disposal restrictions for Third
Third hazardous wastes (55 FR 22520).
EPA. granted a two-year national
capacity variance to allow the continued
storage of lead-bearing hazardous
material! in waste piles (considered a
form of land disposal) prior to smelting.
The variance has now expired and these
untreated wastes became prohibited
from land disposal on May a 1992. At
the time it granted the national capacity
variance, the Agency indicated its intent
to address the concerns raised by the
secondary lead smelting industry to
allow the continued storage of these
materials in piles prior to lead recovery.
While the Agency has published a
proposal that would address this
problem, the Agency has not yet
finalized such a rule. The Agency
believes that the continued storage of
these lead-bearing hazardous materials
in piles at smelting facilities prior to
recovery is preferable to any alternative
management available and consistent
with the Agency's goal of waste
minimization. Although the Agency is
developing a solution that would allow
the continued management of these
wastes prior to lead recovery, until final
standards are issued, it would be
infeasible as a practical matter for
regulated parties to design and construct
the capacity to store the materials
properly. This practical infeasibility
results in an industry-wide, short term
unavailability of non-land based storage
capacity preceding treatment
Therefore, EPA is taking regulatory
action to approve an extension of the
LDR effective date applicable to owners
and operators of secondary lead
smelters who are engaged in the
reclamation of lead-bearing hazardous
materials. This extension applies only to
lead-bearing hazardous wastes placed
in a staging area immediately prior to
being introduced into a lead smelter.
EPA believes that this extension to the
LDR effective date is appropriate and
consistent with the Agency's overall
objective of encouraging recycling. No
further applications will be required a!
this time from persons granted the
extension of this action. However, EPA
is requiring such persons (o maintain
certain recordkeeping, and to meet
certain other requirements to qualify for
the extension.
EFFECTIVE DATE; This notice becomes
effective on June 5.1992.
ADMESSES: The official record for this
notice Is identified as Docket Number F-
92-CD2P-FFFFF, and is located in the
EPA RCRA Docket, room 2427, U.S.
Environmental Protection Agency, 401 M
Street SW Washington, DC 20460. The
docket is open from 9 ajn. to 4 p.m.,
Monday through Friday, except on
Federal holidays. The public must make
an atpporabeent to review docket
materials by calling (202) 260-9327. The
public may copy a maximum of 100
pages from any regulatory document at
no cost. Additional copies cost $0.20 per
page.
FOR FURTHER INFORMATION CONTACT:
For general information contact the
RCRA Hotline at (800) 424-9346 toll-free
or pTO) 920-8810 locally. For
information on specific aspects of this
notice, contact Nick Vizzone, Office of
Sehd Waste, Capacity Programs Branch
(OS-321W), US. Environmental
Protection Agency, 401 M Street SW.,
Washington. DC 20460, (703) 308-8477
SUPPLEMENTARY INFORMATION:
Outline
I. Backgyomd
A. History
B. Proposed Containment Building
ftinnrlarrifr
II. Justification for the Case-by-Case
Extension
A. Demonstration of Part 40 CFR 268 5
B. Coackntos
III. Requirements for the Case-by-Case
Extension
IV. CondAiea* of Further Extension
1. Background
A. History
In MtH. Congress enacted the
Hazardons and Solid Waste
Amendments (HSWA), which amended
the Resource Conservation and
Recovery Act (RCRA). Among other
things, HSWA required EPA to develop
regulations that would impose, on a
phased schedule, restrictions on the
land disposal of hazardous wastes in
particular, sections 3004 (d) through ;g)
prohibit the land disposal of certain
hazardous wastes by specified dates in
order to protect human health and 'he
environment, br addition, section
3004(m) requires EPA to set "levels cr
methods of treatment, if any, which
substantially diminish the toxicity of the
waste or substantially reduce the
likelihood of migration of hazardous
constituents from the waste so that
-------
-------
ATTACHMENT E
Solid Waste Disposal Facility Criteria;
-------
51536 Federal Register / Vol. 58. No. 189 / Friday, October 1, 1993 / Rules and Regulations
ENVIRONMENTAL PROTECTION
AGENCY
40CFR Part 258
(FRL-47S21/EPA530-Z-93012}
Solid Waste Disposal Facility Criteria;
Delay of Compliance end Effective
Oate9
AGENCY: Environment;)! Protection
Agency (EPA).
ACTION: Final rule.
summary: On October 9. 1991. EPA
promulgated revised Federal criteria for
Municipal Solid Waste Landfills
(MSWLFs) undttr subtitle D of the
Resource Conservation and Recovery
Act (RCRA). Today's final rule amends
these criteria by delaying the general
d.-tte for compliance with the criteria
until April 9. 1994 for certain small
landfills and by delaying the effective
date of subpart G, Fincncial Assurance,
until April 9. 1995 for all MSWLFs. In
addition, the MSWLF criteria art)
amended by removing the exemption
from the ground-water monitoring
requirements and delaying the date for
compliance with all requirements of the
MSWLF criteria for two years for
owners and operators of MSWLF units
in arid and remote areas that meet the
qualifications of the small landfill
exemption in the MSWLF criteria.
Additionally, the date of final cover
installation is extended for owners'
operators MSWLFs units that cease
rocnipt of waste by their compliance
d.ilp.. Finally, the compliance date is
c!oLived for certain MSWLFs in the mid-
west receiving flood-related waste from
it federally designated disaster aroo.
B&ouuse states/Tribes may have earlier
effective dates or other requirements in
their own stule/Tribal regulations,
owners ofttt-operators of MSWLFs are
tmcourageri-to consult with (heir state'
Tribe
effective datf.s: The amendments in
this 5i:nl r--i!e are effective October 9.
) 993,1'xmpt for the amendments to
2S8.70 am! 258.74 ir. subpart CI
wliich arc effectivo April 9. 1995
The effective date of subpart C of pen
1^6 ($
-------
FederaJ Register / Vol. 58, No. 189 / Friday, October 1. 1993 / Rules and Regulations S1S37
Midwest) to comply with tho original
uffective dates in part 258. Thus, the
Agency believes tnat it has the authority
io make today's rule effective in less
than 30 days in accordance with section
553 of the Administrative Procedures
Act. 5 U.S.C. 553(d) (1) and (3).
B. Overview of the Subtitle D Effective
Dales as Promulgated on October9.
1991
On October 9. 1991, EPA promulgated
h rule under subtitle D of the Resource
Conservation and Recovery Act and
section 405 of the Clean Water Act
portoining to the disposal of solid waste
and sewage sludge in MSWLFs (55 FR
50978 (October 9. 1991)). The
regulations and effective dates of the
criteria were originally promulgated as
follows. The criteria applied to owners
and operators of all MSWLF units that
receive waste on or after October 9.
1993. Landfill owners and operators that
stopped accepting waste before Octobor
9. 1991 were not required to comply
with tho regulations. Those landfill
owners and operators that stop
accepting waste between October 9,
1991 ana October 9, 1993 were exempt
from all of the regulatory requirements
except for the final cover (found in 40
CFR 258.60(a)), which had to be applied
within six months of last roceipt of
waste. Owners and operators that
cdntini^ed to receive waste beyond the
October 9,1993 effective date were
required to comply with the remainder
of the landfill regulations (including
location restrictions, operation, design,
ground-wator monitoring and corrective
action, closure and post-closure, and
financial assurance). Additionally, the
regulations provided for a phase-in of
two of the more costly requirements: the
financial assurance requirements
(effective April 9, 1994) and ground-
water monitoring and corrective action
requirements (effective October 9,1994
through October~9, 1996). Finally, the
regulations allowed for an exemption
from the design, ground-water
monitoring and corrective action
provisions for very small arid and
remote landfills that mot tho criteria of
258.1(0.
C. Implementation of the MSWLF
Criteria
Section 4005(c)(1)(B) of RCRA, as
amended, requires states to develop end
implement permit programs or other
systems of prior approval and
conditions to ensure that tho MSWLFs
ore complying with the MSWLF criteria.
(The Agency Intends to extend to Indian
Tribes the same opportunity to apply for
permit program approval as is available
to states. Providing Tribos with the
opportunity to apply for approval to
adopt and implement MSWLF permit
programs, while not a statutory
requirement if) RCRA section
4005(c)(1)(B), is consistent with EPA's
Indian Policy. The Agency plans to
propose the concept of Tribal permit
program approval when a tentative
notice of permit program adequacy is
published for the first Indian Tribe
seeking program approval.) EPA's
implementation role is largely to review
and determine whether these state/
Tribal permit programs are adequate.
EPA believes that for permit programs to
be considered adequate, a state/Tribe
must have the capability of issuing
permits or some other form of prior
approval for all MSWLFs in the state/
Tribe, and must establish requirements
adequate to ensure that owners and
operators w.ll comply with the federal
landfill criteria. A state/Tribe also must
be able to ensure compliance through
monitoring and enforcement actions and
must provide for public participation in
their permitting and enforcement
actions.
EPA-approved state/Tribal permit
programs have the opportunity to
exercise more flexibility and discretion
in implementing the criteria according
to local conditions and needs. Owners
and""6perators of MSWLF units located
within the jurisdiction of a state/Tribe
with an approved program may benefit
from this potential flexibility, which
extends to many parts of the MSWLF
regulations. For example, owners and
operators of MSWLF units in
unapproved states/Tribes must design
their new units and lateral expansions
of existing units with a composite liner
in compliance with 40 CFR 258.40(b),
whereas approved states/Tribes may
allow an owner/operator to use an
alternative design based on the
performance standard described in 40
CFR 258.40(a). Because of the flexibility
provided to an approved state permit
program, and because state permit
program approval is mandated by
section 4005(c)(1)(B) of RCRA, EPA
fully expects that most states will apply
for and receive full approval of their
MSWLF permit programs, thereby
maintaining the lead role in
implementing and enforcing the
MSWLF Criteria promulgated under 40
CFR part 258
States are currently in various stages
of the program approval process. Some
states nave received full program
approval, while several states have
received "partial" program approval,
whereby only some portions of the state
permit program have been approved
while the remainder of the program is
awaiting approval pending completion
of statutory and/or regulatory changes
by the state. In situations where a state
permit program is not approved, or
where portions of a program are not
approved (in the case of a partial
approval), the MSWLF criteria (or
unapproved portions of criteria) are
implemented by the owner and
operator, with no Federal permitting
program or interaction. In such
situations, where the MSWLF criteria
are "self-implementing", each owner/
operator must document compliance
and maintain this documentation in the
operating record.
D. Summary of Proposed Rule
When the municipal solid waste
landfill criteria were developed, EPA
included a number of features that serve
to facilitate owners' and operators'
ability to come into compliance by the
promulgated effective dates, These
features include phased-in effective
dates, certain exemptions for very small
arid and remote landfills, and numerous
opportunities for flexibility in states/
Tribes with EPA-approved permit
programs. Despite these features, the
Agency received a significant number of
requests to extend the effective date of
the MSWLF criteria. These requests
came primarily from local governments
that own/operate smaller landfills who
related their problems with meeting the
effective date, including: (1) inability to
comply with unfunded federal
requirements: (2) lack of flexibility in
unapproved states; and (3) delays In
gaining access to new waste
management facilities. Therefore, on
July 28.1993. the Agency proposed to
amend the municipal solid waste
landfill criteria (58 FR 40568) to extend
the effective date of the Criteria. The
proposal was not intended to change the
environmentally protective features of
the MSWLF criteria, but would provide
certain owners and operators with
additional time to come into compliance
with the MSWLF criteria requirements.
The July 28th notice proposed to
amend the criteria irHour areas. First,
the Agency proposed to delay the
effective date of the criteria until April
9,1994 for certain small landfills that:
dispose of 100 tons of waste per day or
less; are located in a state that has
submitted an application for permit
program approval by October 9,1993 or
are located on Indian Lands; and are not
currently on the National Priorities List.
Second, EPA proposed to delay the
effective date of Subpart C, Financial
Assurance, until April 9,1995 for all
MSWLFs. Third, in response to a U.S.
Court of Appeals decision, Sierra Club
v. United States Environmental
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51538 Federal Register / Vol. 58, No. 189 / Friday, October l, 1993 / Rules and Regulations
Cir. 1993), the Agency proposed to
remove the exemption from the ground-
water monitoring requirements in 40
CFR 258.50-258.55, for owners and
operators of MSWLF units in arid and
remote areas that meet the qualifications
of the small landfill exemption outlined
in 40 CFR 258.1(f). Additionally, EPA
proposed to extend the effective date for
all requirements of the MSWLP criteria
for a period of two years, until October
9,1995, for all MSWLF units in arid and
remote areas that qualify for the small
landfill exemption under 258.1(f).
Lastly, the Agency proposed to amend
the final cover requirements by
requiring owners/operators of MSWLF
units that cease receipt of waste by their
effective date to complete final cover
installation by Octolwr 9,1994 except
for very small MSWLFs. Very small
MSWLFs in arid and remote areas thai
qualify for the small landfill exemption
(under 258.1(f)) and cease receipt of
waste before their effective date of
October 9,1995 must complete final
cover installation by October 9,1996.
III. Response to Comments and
Analysis of Issues
The 30-day comment period for tho
July 28th proposed rule ended on
August 27,1993. The Agency received
over 300 comments on the proposal.
This section summarizes and addresses
the major comments as they relate to the
four major amendments in the July 28,
1993 proposal. The Agency received a
number of comments on the MSWLF
criteria not directly related to the issue
of delaying the effective date. The
discussion that follows is limited to the
major issues relevant to the July 28th
proposal. A discussion of the remaining
comments can be found in a background
document available in the RCRA Docket
Information Center.
A. Delaying the General Effective Dote
In the July 28th proposal, EPA
requested comment on a proposed six-
month delay of the effective date (to
April 9,1994) for MSWLFs accepting
100 TPD or less of any combination of
household, commercial, or industrial
solid waste on an average annual basis
that are located in either a state that has
submitted an application for permit
program approval by October 9,1993 or
on Indian lands and are not on the
Superfund National Priorities List
(NPL). The majority of commentors
were generally in favor of the proposed
delay. The major comments submitted
on this portion of the proposal are
summarized below.
1. A Six-Month Time Frame
The proposed rule provided for a one-
time, six-month delay of the general
effective date. Some comiren'.ors
questioned the appropriateness of the
Agency's choice of a six-month delay of
the effective date. Proposals from
commentors ranged from total
opposition to any delay to enthusiastic
support for a longer delay by as much
as two years. Commentors who
supported the extension cited many
reasons, including the following: (1)
inability to comply with unfunded
federal requirements; (2) lack of
flexibility in unapproved states; and (3)
delays in gaining access to a new waste
management facility. As for those who
supported a longer delay by as much as
two years, these commentors believed
that six months was too short based on
their specific situation. As stated in the
proposal, the Agency chose a six-month
delay to accommodate the parties most
in needowners and operators, such as
small communities (including local
governments that own/operate
MSWLFs)who have made good faith
efforts to seek alternative disposal
facilities and need some limited
additional time to complete those
efforts. 58 FR 40570-71. While six
months may not be enough time for all
owners and operators to complete,
necessary actions, EPA does not want to
further delay the implementation of the
critoria promulgated almost two years
ago. This additional time is not
designed to solve the problems facing
communities that recently started the
siting process or who are many months
or years away from operating a new
facility. Lengthy delays could increase
the potential for environmental
problems (e.g., failure to close
substandard landfills) and would
penalize those who took tho necessary
steps to comply with the October 9,
1993 effective date. Therefore, the
Agency did not find these arguments to
delay the effective date beyond six
months to be persuasive.
Other commentors suggested that EPA
should delay the general effective date
for more than six months to allow EPA
more time to approve additional state
permit programs. EPA has determined
that, on the average, review and
approval of a typical stati j. errail
program application can bo completed
within approximately six months. Based
on current information from states, EPA
believes that all or almost all states will
submit an application for approval by
October 9,1993. This six-month
extension will ensure In most cases that
the federal criteria would not become
effective before the state permit program
was approved, thus allowing many
owners and operators to avoid the
situation of gearing up to meet federal
standards and then, a few months later,
changing to meet newly approved state
standards. In addition, this additional
time will allow a vast majority of
MSWLF ownors and operators to take
advantage of the flexibility and the
potential cost savings available when
states are approved.
2.100 Tons Per Day or Less Size
Limitation
The proposed rule limited the six-
month extension to smaller landfills
that accept 100 tons per day or less of
any combination of household,
commercial, or Industrial solid waste
The Agency received a numbor of
comments on this restriction. Some
commentors suggested an increased
tonnage limit (up to 750 TPD), while
others questioned the need to limit tho
extension based on the amount of waste
accepted by the landfill and fell that tho
extension should be available to owners-
and operators regardless of the amount
of waste accepted per day (i.e., a blanket
extension). As staled in the proposal,
the Agency believes that the 100 TPD or
less cut-off is representative of the
majority of smaller community landfills
that have had the most difficulty coming
Into full compliance by the October 9,
1993 doadline, because financial
conditions, legal challenges, and
geography have created significant
obstacles to compliance, often despite
good-faith efforts to comply. For
example, many of the smaller landfills
intend to close, and their users will
instead send their waste to a regional
waste management facility where thej
can take advantaga of economies of
scale. The process of regionalization.
including closure of their existing
MSWLF and construction of a new
transfer station, has taken more time
than many small communities had
originally anticipated. Additionally, the
Agency is concerned that increasing the
tonnage or allowing a "blanket" or
unlimited extension, as suggested by
some commentors, would not fulfill
EPA's goal of granting relief to only
those most in needprimarily small
communities. By setting the limit at 100
TPD, the Agency targets relief to the
greatest extent possible while ensuring
that most waste, as of October 9,1993,
will be disposed in accordance with thf
requirements of 40 CFR part 258. As
discussed In the proposal, setting (he
limit at 100 tons per day would provide
potential relief to approximately 75
percent of the MSWLFs in the country
which manage only about 15 percent of
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Federal Register / Vol. 58, No. 189 / Friday. October 1, 1993 / Rules and Regulations 51539
One commentor argued that the
Agency should have adhered to its own
definition, in the October 9,1991 rule,
of a small landfill used for the small
landfill exemption found at 258.1(f)
(i.e., 20 tons per day). In developing the
proposed size limitation, EPA found
that landfills accepting no more than
100 tons per day of solid waste tend to
be those experiencing the most severe
budget and technical problems. The
Agency did not set the waste acceptance
limit for this extension at 20 tons per
day, because the scope of the problem .
appeared to extend to somewhat larger
landfills, primarily those serving
communities with a population up to a
range of 45,000 to 57,000 (i.e., landfills
accepting approximately 100 tons per
day). Additionally, a portion of the
landfills accepting 20 TPD or lesswill
oualify for the two year delay of all of
tne MSWLF criteria (see subsection D;
Very Small Arid and Remote MSWLF
Extension), if they meet the criteria of
the small landfill exemption in 258.1(f).
Therefore, the Agency is retaining the
100 TPD limit in the final rule. As in the
proposal, it is important to note that the
effective date for MSWLF units
accepting greater than 100 TPD will
continue to be October 9,1993.
In the proposed rule, the Agency
solicited comments on whether two
calculations were necessary to
determine whether an MSWLF unit
qualified and continued to be eligible
for the extension. First, to qualify for the
extension, the MSWLF unit would have
had to dispose of 100 tons per day or
less of solid waste between October 9,
1991 and October 9,1992. Second, the
owner/operator of the MSWLF unit
would not be allowed to dispose of
more than an average of 100 TPD of
solid waste each month between
October 9,1993 and April 9,1994. The
"historical" (e.g., October 9,1991
through October 9,1992) time frame
was suggested mainly to assure that
larger landfills would not alter the
amount of waste they are presently
accepting in order to take advantage of
today's six-month extension, while the
monthly average calculation was
intended to ensure that the "small"
landfills would remain so during the
extension period. As discussed in this
preamble, today's extension is intended
i'or smaller landfills already in
existence.
A few commentors generally
supported the need for an historical
time frame calculation to determine that
the MSWLF qualifying for the extension
was indeed a small landfill. However,
numerous commentors, including many
small landfill owners and operators,
cited many reasons why they believed
the proposed method of determining the
historical time frame (i.e., based on the
average collected during the year
October 9,1991 through October 9,
1992) was unnecessarily restrictive. For
example, commentors felt the historical
time frame did not consider that
unusual circumstances (e.g., sudden
additional incoming waste due to
closure of a neighboring landfill during
the target year) may have increased the
quantity of waste to a landfill during the
target period. Commentors also were
concerned that a great deal of time and
resources could be spent in determining
whether or not a landfill, with no scales
or past records, qualified for the
extension. Commentors nyteJ that
recordkeeping at small landfills, usually
staffed part-time, may be non-existent
for the historical time period, may not
be organized in a way that identifies the
daily tonnage, nor allows such a time
period to be readily identified. These
commentors felt that such resources and
time would be better spent upgrading
the landfill or finding waste
management alternatives. One
commentor argued that their landfill did
not begin receiving waste until after the
historical time period and therefore has
no records.
The Agency recognizes that some of
these situations could prevent some
otherwise deserving landfills fronT"**"
qualifying for the six-month extension.
Today's rule is intended to grant needed
relief to certain MSWLF owners and
operators in a manner that does not
disqualify truly deserving facilities and
does not increase owner/operator
record-keeping burden in order to
qualify for the extension. In an effort to
balance the need to limit the extension
to only small landfills, wh;le at the
same time limiting the burden on those
who qualify, today's final rule provider
that the extension is for units that
"disposed of 100 tons per day or less of
solid waste during a representative
period prior to October 9.1993." The
historical measurement of waste receipt
should be based on the average
acceptance of waste over a
representative period prior to Octobor 9.
1993, as determined by the ownor/
operator. In determining the historical
measurement of waste, the Agency
recommends that owners and operators
determine the averego receipt of waste
during the period of October 9,1991
through October 9,1992. This period of
time should provide the most current
representative "snapshot" of wa&to
receipt at a MSWLF unit Waste receipt
at MSWLF units after October 1992 may
not be as representative due to changes
in practices (either downsizing or
upgrading) as a result of the impending
October 9,1993 effective date. However,
in the instance that the owner/operator
does not have records for this period, or
believes that this period is not
representative of their past receipt of
waste, then the owner/operator may
choose an alternative period (e.g.Tthe
most recent twelve consecutive month
period not impacted by extraneous
circumstances). The historical
calculation method adopted for today's
extension is implicitly the same as the
historical measurement method MSWLF
owners and operators use in
determining If their MSWLF will meet
the small landfill exemption (less than
20 TPD) of 258.1(0. Ownere and
operators therefore will have the
flexibility to base their historical
determination of average waste receipt
on their available records while
considering special circumstances.
It is the responsibility of the owner/
operator to document an historical
acceptance of waste of 100 TPD or less.
The Agency will not require owners and
operators to maintain records on the
amount of waste the facility accepts, but
if the owner/operator believes thai the
facility may be close to the 100 TPD
limit, then it may be in the owner/
operators' best interest to develop end
maintain some indication on the
amount of waste accepted given the
possibility of citizen suits being filed
undor section 7002 of RCRA.
Commentors supported the proposed
monthly calculation during the
extension period to continue to qualify
for the extension. Therefore, MSWLFs
will continue to be required to accept
100 TPD or less based on a monthly
average during the time period of
October 9,1993 until April 9,1994 to
qualify for an extension.
Finally, the proposed rule requested
lumment on methods of calculating tho
tons per day accepted by facilities. EPA
suggested two methods: (1) divide the
total annual amount of waste received
by 365 days or (2) conduct a one-time
measurement of a day's typical full
trash-hauling vehicles, then estimate the
weight from volume of trash-hauling
vehicles by using a conversion factor
(e.g.. one ton equal to three cubic yards
of waste) or using sales/acceptance
recoipts from trash haulers. Commentors
generally agreed that both of theso
methods to calculate the acceptance of
waste would suffice for the majority of
their situations. Several commentors
suggosted the use of a conversion factoi
of one ton equal to five cubic yards of
noncompacted waste. Rather than set
strict calculation methods, the Agency
believes that tho approach should
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51540 Federal Register / Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations
operator use reasonable and defensible
assumptions in calculating their
tonnage.
3. Lateral Expansions
The proposed rule limited the
extension to existing units and to lateral
expansions of existing units to
accommodate trench and area fills. A
few .commentors were concerned that
landfills qualifying for the extension
would laterally expand over a larger
area than actually needed, thus greatly
Increasing the size of their existing unit
by the new April 9,1994 effective date.
The commentora proposed that EPA
limit the capacity of MSWLF unit lateral
expansions to not exceed six-months of
capacity for the entire MSWLF unit. The
Agency feels that this type of limitation
woiild create an unnecessary
complication for owners and operators
in implementation of this extension and
that this issue already Is addressed in
the current definition of an existing
unit. The definition of "existing
MSWLF unit" in ง 258.2, defines such a
unit as one that is receiving solid waste
as of the effective date of the landfill
criteria iwith the caveat that waste
placement in the unit be consistent with
past operating practices or modified
practices to ensure good management.
The Agency has interpreted this to mean
that an existing unit is defined by the
areal extent of waste (sometimes
referred to as the waste "footprint")
placed as of the effective date of the
criteria and that the spreading of waste
over a large area to avoid the liner
requirements is not acceptable (see 56
FR 51041, October 9,1991).
A commentor suggested that EPA
should only have granted an exemption
to landfills that were undertaking
vertical expansions, and not extend the
exemption to lateral expansions. As
noted earlier, the major difficulties in
meeting the criteria deadline appear to
fall mainty.on smaller community
landfills aod the extension therefore is
largely directed at such landfills. Many
of these smaller landfills use trench and
area fill practices. For example, in a
trench fill operation, a small trench is
excavated, filled, and covered in a
relatively short period of time. As the
old trench is filled, it is extended to
accommodate additional waste. This
extension is by definition a lateral
expansion. Limiting the extension to
vertical expansions would therefore
disrupt these customary practices and
limit the extension to considerably
fewer landfills than EPA intended.
Therefore, today's final rule continues
to allow existing units and lateral
expansions of existing units to receive
the six-month extension.
4. State Submittal of a Permit Program
Application
The proposed rule limited the six-
month extension only to owners and
operators of MSWLFs in states that have
submitted an application for permit
program approval by October 9,1993 or
are located on Indian Lands. Some
commentors questioned the need for the
state to have submitted an application
in order for the owner/operator to
qualify for the extension. The Agency
continues to work toward its goal of
approving all states and Tribes (to the
extent they apply). Approval of State/
Tribal permit programs is a high priority
and the Agency does not want the
extension to detract from this goal. EPA
believes that the linkage of the
extension to submission of an
application will serve as impetus for
states to submit their applications by
October 9,1993 and for advancing the
Agency's goal of approving all states by
April 9,1994. In fact, the Agency now
believes that every state except Iowa
will submit an application by October 9.
1993.
In the proposed rule, the Agency
indicated that when it published the
final rule, It would includa a list of
states who have submitted an
application by the date on which the
final rule was signed. 58 FR 40572.
Because most states have now subletted
an application, for purposes of
simplicity, the following is a list of
those states who have not submitted an
application as of the date of signature:
Alaska, American Samoa, Arizona,
Guam, Hawaii, Iowa, Maine, New .
Jersey, Northern Marianas, Ohio, Ptierto
Rico, Rhode Island, and the Virgin
Islands. Because most of these states are
expected to apply between the date of
signature and October 9,1993, owners
and operators of MSWLF units located
in these states are encouraged to contact
their state to find out whether the State
has submitted an application by October
9,1993.
Due to the time and resources
required to deal with the effects of the
Great Flood of 1993, the state of Iowa
has indicated that it will not be able to
apply for approval of its permit program
by Ortober 9,1993, although the state
had originally planned to ic so. In an
effort not to penalize thoso small
landfills in need of relief located in the
state of Iowa, the final rule does not
Include the requirement that Iowa
submit a permit program application by
October 9,1993 for owners and
operators in that state to take advantage
of the six-month delay. Owners and
operators in Iowa, however, will be
required to meet all other requirements
to qualify for the six-month extension in
today's final rule.
In the proposal, the Agency provided
that owners and operators of MSWLFs
located on Indian lands would be
eligible for the six month extension
even if the Tribe had not submitted an
application for permit program approval
by October 9.1993. As discussed in the
proposal, RCRA does not require Indian
Tribes to develop a permit program for
MSWLFs. Because many of the landfills
on Indian lands could qualify for
today's six-month extension by virtue of
the fact that they accept less than 100
TPD and are not on the National
Priorities List, the Agency proposed to
allow MSWLF units on Indian lands to
take advantage of the six-month
extension, even if the Indian Tribe has
not submitted an application for permit
program approval by October 9,1993.
Commentors agreed with this provision
as long as all other requirements for the
extension are fulfilled. Therefore,
today's final rule allows owners/
operators located on Indian Lands to be
granted the six-month extension as long
as all of the other requirements of this
rule are met.
No comments were received that
suggested changes to the proposed
definitions of "Indian land or Indian
country" and "Indian Tribe or Tribe."
Therefore, these definitions are retained
in today's final rule. While the
definftion of Tribes in today's final rule
does not explicitly include Alaska
Native Villages, EPA believes that, to
the extent these entities exercise
substantial governmental duties and
powers, they would be eligible to apply
for'permit program approval. For
purposes of today's rule, as with Indian
lands in other States. EPA is allowing
landfills on Native Village Lands to be
eligible for the six-month extension
whether or not the Village has
submitted an application for permit
program approval.
Some commentors suggested that EPA
delegate to states who have submitted a
permit program application by October
9,1993 more flewbility in
implementation of the delay.
Commentors suggested, for example,
that such states should have the
flexibility to: Determine the need for a
delay on a site-by-site basis, to grant
longer than a six-month extension, or to
waive the 100 TPD limit. As discussed
throughout this preamble, the Agency
set the length of the extension and size
criteria so as to target limited relief for
those MSWLF units In greatest need
small landfills. Therefore, in order to
maintain this focus, the Agency will
continue to require that these criteria be
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However, other commentors were
concerned that a delay of the criteria
would undermine states' efforts in
implementing the MSWLF criteria (e.g..
oppose state's existing closure
schedules for substandard landfills). As
stated in the proposal, a state/Tribe,
regardless of its permit program
approval status, may impose more
stringent effective dates and/or more
stringent criteria for qualifying for an
extension (e.g., maintain current closure
schedules) if they so choose. Therefore,
the extension should not have the
negative effect predicted by these
commentors.
S. National Priorities List
The proposed rule did not extend the
six-month extension to MSWLFs
currently on the Superfund National
Priorities List as published in appendix
B to 40 CFR part 300. Commentors
agreed with this exclusion; therefore,
the final rule retains this provision.
Some commentors suggested that the
extension be further restricted by
disallowing any MSWLF that is on a
state Superfund list or in violation of
another state environmental regulation.
As discussed in the previous section,
states may always be more stringent
(e.g., prevent MSWLFs on their state
Superfund lists-from gaining an
extension) in their approach to the
extension.
6. Other Limitations Suggested by
Commentors
A few commentors requested that
EPA limit the extension to prohibit
MSWLFs that qualify from accepting
non-hazardous industrial waste. Under
the criteria as promulgated on October
9,1991, MSWLFs may accept non-
hazardous industrial waste to be co-
disposed with household waste. The
Agency did not limit today's extension
in the manner suggested for the
following reasons: (1) The prohibition of
non-hazarck3Us industrial waste would
be difficult to Implement and enforce;
(2) this waste stream typically
represents a small fraction of the entire
waste sent to a MS WLF; (3) for some
generators, the local MSWLF represents
the only economical method of disposal
of their non-hazardous industrial waste;
and (4) this is a one-time extension for
a short period of time (i.e., six months).
Therefore, the final rule will allow
MSWLFs qualifying for the extension to
accept non-hazardous industrial waste
for co-disposal with housohold waste.
Finally, some commentors suggested
that In order to qualify for the extension,
the MSWLF must be in compliance with
all of the location restrictions of subpart
B of the criteria by the effective date.
EPA did not limit the extension based
on a facility meeting the location
restrictions because many of the
restrictions (e.g., wetlands, fault areas,
seismic zones) do not apply to existing
units, the major target of the extension.
In addition, under the criteria as
promulgated, existing units that cannot
meet the requirements for airports,
floodplains, or unstable areas already
have until October 9,1990 to close
(unchanged by today's rule). Limiting
the extension for these facilities would
not have much of an effect Therefore,
today's final rule does not place location
restrictions on MSWLFs eligible for the
extension.
B. Delaying the Financial Assurance
Effective Date
The proposed rule provided for a ono-
year extension of the financial assurance
requirements (from April 9,1994 to
April 9,1995) for all MSWLFs.
regardless of 6ize. The majority of
commentors supported the need to
extend the financial assurance
requirements. Commentors noted that
the one-year delay provides time for the
owners and operators to budget and to
acquire the appropriate financial
assurance mecnanism for their
MSWLFs. The Agency, in setting the
original April 9,1994 effe-jtive date for
the financial assurance requirement,
believed that this date would allow
adequate time to promulgate a financial
test for local governments and another
test for corporations (see 56 FR 50978).
However, the Agency currently
estimates that neither financial test will
be promulgated within the time frame
anticipated. The Agency believes that
local governments should have these
financial tests available te them before
the financial responsibility provisions
become effective. The delay of one year
provided in this rule should enable EPA
to finish promulgation of these tests and
should ensure that owners and
operators will have the opportunity to
evaluate their needs based on these
financial tests. As a result, many local
governments will be able to realize a
significant decrease in the cost of
compliance with the financial
responsibility requirements, while
assuring that the costs associated with
closure, post-closure, and known
corrective action at the MSWLFs will be
met.
A few commentors suggested that
EPA extend the effective date of the
financial assurance requirements
beyond the proposed one-year delay.
The Agency anticipates that the one
year extension will be sufficient time to
complete the proposal and
promulgation of the financial test*. EPA
also bolieves that one year should
provide adequate notice to affected
parties so they may determine whethor
they satisfy the applicable financial test
criteria for all of the obligations
associated with tlielr facilities or
whether they need to obtain an alternate
instrument for some or all of their
obligations. The Agency notes that
approved states/Tribes have the
flexibility to develop alternative
financial mechanisms that meet the
criteria specified in ง 258.74(1) for use
by their owners and operators. This may
include development of a state financial
test. Therefore, today's final rule retains
the one year extension for financial
assurance.
C. Very Small Arid and Remote MSWLF
Extension
1. Commentor-Suggested Limitations to
Qualify for the Two-Year Extension
The October 9,1991 Final Rule for the
MSWLF Criteria included an exemption
for owners and operators of certain
small MSWLF units from the design
(subpart D) and groundwater
monitoring and corrective action
(subpart E) requirements of the Criteria.
See 40 CFR 258.1(f). To qualify for the
exemption, the small landfill had to
accept less than 20 tons per day, on en
average annual basis, exhibit no
evidence of ground-water
contamination, and serve either
(i) A community that experiences an
annual interruption of at least three
consecutive months of surface
transportation that prevents access to a
regional waste management facility, or
(ii) A community tnat has no
practicable waste management
alternative and the landfill unit is
located in an area that annually receives
less than or equal to 25 inches of
precipitation.
In adopting this limited exemption,
the Agency maintained that It had
complied with the statutory standard to
protect human health and the
environment, taking into account the
practicable capabilities of small landfill
owners and operators. See discussion in
56 FR 50991.
In lanuary 1992, the Sierra Club and
the Natural Resources Defense Council
(NRDC) filed a petition with the U.S.
Court of Appeals, District of Columbia
Circuit, for review of the subtitle D
criteria. The Sierra Club and NRDC suit
alleged, among othor things, that EPA
acted illegally when It exempted these
small landfills from the ground-water
monitoring requirements. On May 7,
1993, the United States Court of
Appeals for the District of Columbia
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51542 Federal Register / Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations
the Sierra Club and NRDC challenge to
the small landfill exemption. Sierra
Club v. United States Environmental
Protection Agency, 992 F.2d 337 (DC
Cir. 1993).
The Court held that under section
4010(c), the only factor EPA could
consider in determining whether
facilities must monitor their ground
water was whether such monitoring was
"necessary to detect contamination,"
not whether such monitoring is
"practicable." The Court noted that
while EPA could consider the
practicable capabilities of facilities in
determining the extent or kind of
ground-water monitoring that a landfill
owner/operator must conduct, EPA
could not justify the complete
exemption from ground-water
monitoring requirements. Thus, the
Court vacated the small landfill
exemption as it pertains to ground-Water
monitoring, directing the Agency to
"* * * revise its rule to reouire ground-
water monitoring at all landfills." (The
Court decision did not affect the small
landfill exemption as it pertains to the
design requirements.)
Therefore, today's final rule, as
required by the Court, modifies the
small landfill exemption whereby,
owners and operators of MSWLF units
that meet the qualifications outlined in
ง 258.1(f) are no longer exempt from
ground-water monitoring requirements
in 40 CFR 258.50-258.55.
The proposed rule, while removing
the exemption from ground-water
monitoring for these very small
landfills, provided a two-year extension
of the effective date for those landfills
in order for them to rethink and act on
their waste management options in light
of the Court ruling. Some commentors
proposed limiting the two-year
extension to only the ground-water
monitoring requirements of part 258.
The Agency believes that many of those
facilities that qualified for the small
landfill exemption made a decision to
remain open based on the costs of
operation without ground-water
monitoring. These landfills acted in
good faith, and should therefore be
allowed to reconsider their overall
decision now that the costs have
fundamentally changed. These facilities
should be given a similar amount of
time that other facilities have had to
make such decisions. (All MSWLFs
were originally given two years notice
following promulgation of the criteria
during which time they could decide
whether to remain in operation when
the criteria take effect.) Therefore, the
final rule provides for an extension for
all of the MSWLF criteria requirements,
for a period of two years, for all MSWLF
units that qualify for the small landfill
exemption (ง 258.1(f)). (It is imj. ortant to
note that this extension is independent
of, and not in addition to, the six-month
extension for MSWLF units accepting
less than 100 TPD.)
2. Alternatives for Ground-Water
Monitoring
The U.S. Court of Appeals, in its
decision, did not preclude the
possibility that the Agency could
establish separate ground-water
monitoring standards for the small dry/
remote landfills that take such factors as
size, location, and climate into account.
Therefore, in the proposal, EPA
requested comments on alternative
ground-water monitoring requirements
for these facilities.
While the Agency received a number
of comments supporting alternative
ground-water monitoring requirements
for these very small landfills, several
commentors requested additional time
to provide suggested alternatives.
Therefore, the Agency will continue to
maintain an open dialogue with all
interested parties to discuss whether
alternative ground-water monitoring
requirements should be established and
will continue to accept information on
alternatives. Information and
suggestions oh alternative ground-water
monitoring requirements can be sent4o>
"Alternative Ground-Water
Monitoring-", Office of Solid Waste (OS-
301), U.S. Environmental Protection
Agency Headquarters, 401 M Street,
SW., Washington, DC 20460.
Commentors also suggested that the
Agency set an effective date for the
ground-water monitoring requirements
for these very small landfills two years
after the promulgation of regulations
regarding alternative ground-water
monitoring for these facilities. The point
of today's action is to respond to the
Court's mandate. At this time, the
Agency is still investigating this issue
and cannot be certain that practicable
alternatives for detecting ground-water
contamination will exist for MSWLF
units that would qualify for the
exemption under ง 258.1(f). Therefore,
today's final rule does not tie the
effective date of ground-water
monitoring for landfills that qualify for
the small/arid and remote exemption to
promulgation of alternative ground-
water monitoring requirements.
D. Modification of Closure Provisions for
Owners/Operators Ceasing Receipt of
Waste by Their Respective Effective Date
The proposed rule modified the
closure requirements for MSWLFs
ceasing receipt of waste before the
effective date by requiring these owners
and operators to complete cover
installation by October 9,1994 rather
than six months after last receipt of
waste. Commentors agreed with the
assessment of the problems associated
with completion of closure activities
within six months of last receipt of
waste. Some commentors restated their
view that the requirement to finish
closure during the late fall/winter
months of October through March
would be most difficult and subject
their facilities to delays, if not rendering
it impossible to complete within the six
month time frame.
A few commentors suggested that the
Agency extend the completion date for
closure activities beyond the proposed
October 9,1994 to accommodate their
specific situation. EPA believes that the
October 9,1994 deadline provides
sufficient time for owners and operators
of closing landfills to complete cover
installation. This would mean that
owners/operators that are subject to the
October 9,1993 effective date would
have at least one year to install a cover,
while owners and operators of landfills
subject to the April 9,1994 Effective
date would have at least six months to
install a cover. Both time frames should
provide at least six months of moderate
weather during which to plan and
install a landfill cover.
Therefore, the final rule retains the
requirement that owners and operators
ceasing receipt of waste before their
effective date (either October 9,1993 or
April 9,1994) complete cover
installation by October 9.1994. Owners/
operators of very small landfills that
qualify for the extension in 258.1(0 who
cease receipt of waste prior to the new
effective date of October 9,1995 must
complete cover installation by October
9,1996. As in the October 9,1991 final
rule, owners and operators failing to
install a cover by these new dates will
subject the MSWLF unit to all of the
requirements of part 258.
E. MSWLFs Receiving Flood Debris
A tremendous volume of debris from
the Great Flood of f993 in the Midwest
is expected to strain the capacity of
certain MSWLFs in that region as well
as interfere with their efforts to comply
with the criteria. On July 28,1993, EPA
asked for comments in the proposal on
how to accommodate landfills that will
be affected by this flood-related debris,
given the original October 9,1993
effective date for the MSWLF criteria
and the extensions proposed at that
time. The comments received generally
acknowledge the need to provide some
relief to such landfills. Wnlle some
commentors requested a special two-
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Federal Register / Vol. 58, No. 189 / Friday, October 1. 1993 / Rules and Regulations 51543
Indicated that six months would
generally suffice, based on post
experience in dealing with floods and
on existing landfill capacity. Several
commentoro requested that states be
delegated the authority to grant targeted
relief to MSWLFs within their state that
were in need.
After reviewing and considering
comments, the Agency developed a
regulatory scenario that meets the
Agency's dual goals of granting roliof to
those MSWLF units affected by the
flood of'03 while maintaining
simplicity for the purpose of
implementation. The final rule contains
a two-stage approach for extending the
effective date tor such landfills, which
is independent of the extensions
discussed earlier in this preamble (e.g.,
for MSWLFs receiving less than 100
TPD).
First, existing MSWLF units and
lateral expansions of existing MSWLF
units may continue to receive waste up
to April 9,1994, without being subject
to part 258 (except the final cover
requirement), if the state determines
that they are needed to receive flood-
related waste from a Federally-
designated disaster area resulting from
the Great Flood of 1993. This provision
responds to GPA's belief that in most
cases, six months will be adequato to
handle flood-related waste especially for
historically smaller landfills Uiat
Ordinarily would have qualified for the
six-month extension for landfills
receiving less than 100 TPD, but now
exceed the tonnage limit due to
acceptance of flood debris. As with
today's six-month extension for MSWLF
units accepting 100 TPD or less, the
extension for MSWLF units accopting
flood-related waste is limited only to
existing units and lateral expansions of
existing units; it is not intended for new
units.
SeconcL existing MSWLF units and
lateral expansions of existing MSWLF
units that have received a six (6) month
extension, may continue to receive
waste without being subject to part 258
(except the final cover requirements),
for an additional period bf time up to
six (6) months beyond April 9,1994. if
the state determines that the MSWLF
unit is needed to receive flood-related
waste from a Federally-designated
disaster area resulting from the Great
Flood of 1993. This second provision
will allow those states that believe that
their owners and operators may need to
operate for an additional period of time
after April 9,1994, to continue to
operate up to another six months
without being subject to port 2S8, only
on an as-needed basis d jttrmlned by the
state. EPA encourages stales to limit the
use of this additional six month
extension only to situations where local
hardships will occur if the site is not
available for continued flood cleanup
activities. EPA does not intend this
flood-related extension to delay
compliance any longer than is necessary
to meet clean-up needs, especially for
larger facilities that are not subject to
the general six-month extension
discussed earlior. In no case, however,
may a state extend the effective date for
these landfills beyond October 9,1994.
Owners and operators of MSWLF
units who receive an extension to
receive flood waste and cease receipt of
waste at the end of that extension must
complete cover installaUon within one
year of the date on which the extension
ended, but in no case shall the cover
installation extend beyond October 9,
1995. Owners and operators of MSWLF
units that continue to accept waste after
their extension expires must comply
with all of the part 258 requirements.
Including: (1) The ground-water
monitoring requirements in accordance
with the schedule in 258.50(c) or in
accordance with an approved state/tribe
schedule and (2) the financial assurance
requirements by April 9,1995.
F. Other Issues Pertaining to the July 28,
1993 Proposal
1. Sewage Sludge Disposal
Commentors agreed that EPA should
not grant removal credits authority to a
POTW unless the POTW sends its
sewage sludge to a MSWLF unit that
complies with the full panoply of the
part 258 rule requirements. Henoe, EPA
will not grant removal credits authority
to POTWs if they send their sludge to
landfills using one of today's extensions
(e.g., small landfills that choose to take
advantage of the six-month extension, or
very small landfills that qualify for the
two-year extension), since such landfills
will not bo in full compliance with part
258.
2. Effects of the Extension on Source
Reduction and Recycling
One commentor felt that an extension
to the MSWLF criteria effective data
would undercut recycling and source
reduction due to continuation of
"cheap" landfill tipping fees. EPA
promotes an integrated waste
management approacKTavoring source
reduction and recycling as the preferred
options. EPA does not believe tnat this
rule will create significant negative
effects on the Agency's goal of
increasing cost-effective source
reduction and recycling. This is a
limited extension, in most cases lasting
only for a six month time frame and as
discussed earlier, affecting only 15
percent of all waste. In addition, many
states have already closed or are in the
process of closing their inadequate
landfills that would fail to meet the
MSWLF criteria requirements. The
overall effect of the criteria continues to
be supportive of both safer disposal and
more incentives for alternatives to
disposal.
IV. Summary of This Rule
Table I provides a summary of the
changes to the effective dates of the
MSWLF critGria as outlined in today'6
final rule.
Table I.Summary of Changes to the Effective Dates of the MSWLF Criteria
General effective date*
MSWLF units ac-
cepting greater than
100 TPD
October 0, 1993
MSWLF units accepting less
than 100 TPD; are not on (he
NPL; and are located In a
state that has submitted an ap-
plication (or approval by
1
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1544 Federal "Register / Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations
Table 1Summary of Changes to the 'Effective Dates of the MSWLF CriteriaContinued
1
MSWLF units ac-
ceptlnj^grealer than
MSWLF units aooeptlng less
then 100 TPD; arenot on the
NPU-and are located In a
stats that has submitted an ap-
plication tor approval by
10W93
MSWLF units that
meet the small land-
fill exemption In 40
CFR ง 256.1(f)
MSWLF units receMng flood-
related waste
the--eftactive data-for to-.
cotton, -operation, deeJgn,
and.doeura/poet-doeure.
r>ate bywhtchto ctosalf cease,
receipt 61 waste by the ;peo-
ntl affective date. ,
inactive date xrf groundwater
monitoring and connective ac-
*on.
tttectlve date bl -financial as-
surance requirements.
October 9. 1994
"Prior to receipt of
waste for new
units; October 9.
1094 through Oc-
tober 8,1996 for
existing units-and -
lateral expansions.
ฆApril B, 1995
October 9,1994
October 9, 1994 for new units;
October 9,1994 through Oc-
tober "9, 1996 for existing
and lateral expansions.
Aprils, 1085
I
October 9. 1996
October 9, 1995 for
new units; Octo-
ber 9, 1996 for
existing and lat-
eral expansions.
October 8, 1995
Within one year of date deter-
mined by State; no later
than Octobers, 1995.
October "9. 1994 for new units;
October 9,1904 through Oc-
- tober 9, 1996 for existing
and lateral expansions.
April 9.1995.
* 'MSWLF receive* waste attar Ms date the urrit must compty'Vrttfi all-of Port 2S8.
Ecoooinic and Regulatory impacts
ReguldtofyJmpact Analysis
TJaderlSxecutive Order 12291, EPA
must'determine whether a new
regulation,is-a"*major"Tule and prepare
a RegtfldtoryImpact Analysis (R1A) In
connectionwith a major rule. A "major"
rule Is defined as one that is-likely to
,*esult in:'(l)an annual'effect on the
3conomy-o'f$100 millionor more; (2) a
majorfacreaseHncostsor prices -for
consumers,'Individual industries,
Federal,"state/Tribal, and local
government agencies or geographic
regtans-.-orOl-significant adverse effects
on competition, employment,
ฆnvestmont, productivity, innovation or
jn:the-ability or-U.S.-based enterprises
ฆ> compete with foreign-based
t itarprises in domestic or export
.arkets.
The amendmontstfo the regulations
outlined-in .this nrimvill, except for the
provision requiring dry/remote very
_/nail .landfills .to perform ground-water
toriitoring, have the effect of reducing
: tqulrements imposed by the 40 CFR
; ait 258 criteria. While the Agency
itimates that increasedicosts to
.-uuseholds lor-the {round-water
uonitoring requirements added as a
tesult of the Court's decision maybe
rignificanl'for.some df the very smallest
immunities, the Agency does not
relieve that this is a major rule for the
uurposes of determining whether to
:ปnduct an RIA. Moreover,mnder
today's final rule, owners and operators
' f MSWLF units that meet the small
landfill exemption of ง 258.1 (0 are
provided regulatory relief by a delayed
TecUve date.
EPA has updated and revised the cost
estimates reported in the preamble for
the proposal Tor today's rule. A detailed
explanation of unit costs and
methodology can be found in a
technical memorandum to the docket.
In estimating the.national annualized
costs attributable tolhe removal of the
ground-water monitoring-exemption for
dry/small.landfills, the Agency defined
small landfills as those accepting less
than 20 tons^per day (TPD), and dry
landfills as those located in areas
receiving less than 25 inches of
precipitation per year. (The Agency
does not have complete data on the
number oT very small landfills that
qualify for the exemption bocause they
are remote; that is, because they
experience three consecutive months
with no surface transportation.
However, the Agency believes that most
ofthese landfills-are captured in the
assumptions used to develop the
estimated number of small arid
landfills.) EPA assumed a universe of
750 dry/small landfills will be operating
in 1995 (approximately 517 1 TPD .
landfills end 232 10 TPD landfills). This
estimate is derived from the municipal
landfill survey of 1986, and 4s based -
upon the closure dates reported by
landfills at that time. EPA assume.'
landfills which reported closure dates
prior to 1995 will nave closed and those
communities have.tumed to larger
landfills which would not be affected by
today's rule. For landfills which
reported closure dates after 1995, EPA
estimated ground-water monitoring
costs.
EPA developed national costs
estimates using most of the assumptions
U6ed in the Regulatory Impact Analysis
(R1A) developed for the revised Criteria.
For the purposes of this analysis, EPA
assumed that landfills would monitor -
ground water during the opera tin^dife
and for a thirty year post-closure care
period (the post-closure care period
requirement may vary in an approved
state). EPA estimated costs 'for two
representative sizes under 20 TPD: A 10
landfill and a 1 TPD landfill. The
Agency assumed that for a 10 TPD
landfill, five well-clusters, with three
wells each would be used. For a one
TPD landfill, EPA assumed three well
clusters with three>wells each would be
used. EPA used overage unit capital
costs for ground-water monitoring,
assuming a well depth of 140 feet. The
Agency recognizes that these average
costs may underestimate costs to some
individual landfills which, due to
remoteness or site-specific
characteristics (e.g., high depth to
ground water), may have higher well
construction costs than estimated. For
example, the depth to ground water in
some dry areas can be several hundred
feet. Digging the wells deeper will likely
result in additional costs'of
approximately $35 to $50 for each
additional foot. This means that the
difference in cost of a well cluster
extending to 140 feet versus a well
cluster extending to 300 feet would be
approximately 25% more for the well
construction costs, which would
increase the initial hydrogeologlc study
and construction costs incurred In one
year by approximately 8 percent for a 1
TPD landfill and 11 percent for a 10
TPD landfill. Additional well depths
would likewise continue to increase
costs. One commentor from Nevada
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Federal Register / Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations 51545
can be over 1,000 feet. Clearly the costs
of digging a well in this situation will
be higher than estimated here.
Additionally, the costs of well
construction in remote areas could be
higher if an expense to transport
equipment to the site is incurred. This
may be a significant cost to
communities which are very remote and
have limited access.
EPA assumed it will cost less to
comply with the ground-water
monitoring requirements in today's rule
for landfills located in states already
requiring ground-water monitoring (39
states required ground-water monitoring
in 1991).
EPA assumed that landfills with short
remaining lives would distribute the
costs of the ground-water monitoring
over the life of the new replacement
landfill.> This is a reasonable
assumption for municipalities which
control tipping fees for residents and
have the ability to spread the costs of
ground-water monitoring over a longer
time period. It will not always be
possible for private landfill owners to
annualized these costs over post-closure
years.
EPA estimates that the national
annualized costs of requiring ground-
water monitoring for all dry/small
landfills is approximately $13 million
per year (in 1992 dollars). This estimate
represents potential costs resulting from
the court decision to require ground-
water monitoring for all dry/small
landfills. EPA expects, however, that
some dry/small landfills would have
joined a regionalized waste management
system prior to the implementation
date, and thus will not incur these
ground-water monitoring costs.
Costs to individual landfills will vary
greatly. Landfills located in states which
already require ground-water
monitoring may not experience any
additionaLcosts. Landfills located in
states with no ground-water
requirements may incur the full cost of
ground-water monitoring.
Size will affect landfill cost. EPA
estimates that the annualized cost (for
1 For example, a landfill which It sxpecied to
close In five yean would distribute the coju acrou
the five years plus the twenty year* a new
replacement landfill would operate. This ability to
average coils of existing landfills and new
replacement landfills w&s assumed in the RIA.
Because the cost analysis In the RIA Indicates that,
except in the most remote or (inaccessible areas,
costs per too for using a larger regional landfill Is
less expensive than for small landfills, EPA
assumed communities would use regional waste
facilities upon closure of small landfills. Since
requirements for large landfills are not being
affected by today's very small landfill ground-water
monitoring requirements, no costs of the
replacement landfill are Included in cost estimate!
presonled today.
thirty years) for ground-water
monitoring at a 10 TPD landfill, with a
ten year operating life, would be
approximately $32,000 or $32 per
household per year. The annualized cost
for ground-water monitoring at a 1 TPD
landfill, with a ten year operating life,
would be approximately $22,000 or
$222 per household per year. Clearly,
costs to the very small landfills (e.g., 1
TPD) may be high per household.
The Agency does not believe a
significant number of MSVLFs will-
experience corrective action costs due to
the Court's decision for several reasons.
First, it is unlikely that continued
operation of these small landfills will
result in ground-water contamination
that requires corrective action. Because
these landfills generally are located in
dry areas receiving less than 25 inches
of precipitation per year, very little
Ieachate will be available for release to
the ground water. Additionally, many of
these dry/small landfills are situated
above aquifers that typically are located
several hundred feet below the ground
surface, thereby creating a significant
natural barrier to threat of
contamination. Second, even if these
landfill owners and operators detected
contamination that would trigger
corrective action, the MSVVLF criteria
currently allow the Director of a state
with an EPA-approved permit program
to waive corrective action under the
circumstances outlined in 40 CFR
258.57(e). Third, of the small landfills
that would have qualified for the small
landfill exemption, it is difficult to
estimate the number of Juse landfills
that will continue to operate now that
they axe required to perform ground-
water monitoring. Many will choose to
close because of these new
requirements.
Thus, given these factors, it is difficult
to estimate the national cost impact of
corrective action on these small
landfills. The Agency believes that few
would contaminate ground water and be
required to perform these clean-up
activities. However, if a landfill did
trigger corrective action in a state that
required clean-up, the Agency estimates
that the average total annualized cost
(over 20 years) of correctfve action for
that landfill would range from
approximately $160,000 to $350,000 per
year. These costs assume pump and
treat clean-up technology and a 40-year
post-closure care period.
Again, most of the cost assumptions
in this estimate are based on unit cost
assumptions from the Regulatory Impact
Analysis for the Revised Subtitle D
Criteria found In docket number F-91-
CMLF-FFFFF.
The Agency believes that the final
rule does not meet the definition of a
major regulation. Thus, the Agency Is
not conducting a Regulatory Impact
Analysis at this time. Today's final rule
has been submitted to the Office of
Management and Budget (OMB) for
review as required by Executive Order
12291.
B. Regulatory Flexibility Act
The Regulatory Flexibility Act (5
U.S.C. 601 et sea.) requires an agency to
prepare, and make available for public
comment, a regulatory flexibility
analysis that describes the impact of a
proposed or final rule on small entities
(i.e., small businesses, small
organizations, and small governmental
jurisdictions). No regulatory flexibility
analysis is required if the head of an
agency certifies the rule will not have
significant economic impact on a
substantial number of small entities.
The estimates of potential total
annualized costs for specific landfills
are discussed above in Section V-A.
However, not all landfills will
experience these costs. Many landfills
are located in states that already require
ground-water monitoring and/or
corrective action and thus there would
be little incremental cost to these
landfills due to the court decision. In
addition, EPA believes there will be a
reduction in small landfills over time as
these landfills close and communities
regionalize.
The amendments to 40 CFR part 258,
except for the provision requiring dry/
remote small landfills accepting less
than 20 TPD to perform ground-water
monitoring, have the general effect of
reducing the requirements of the part
258 criteria, thereby imposing no
additional economic impact to small
entities.
The provision requiring dry/remote
landfills accepting less than 20 TPD to
Eerform ground-water monitoring could
ave a significant economic Impact on
some of these small entities. Agency
data indicate that economic impact will
vary with size, with larger landfills
experiencing a relatively moderato cost
increase per household when compared
to smaller landfills whore economies of
scale are not available. Agency data
indicate that the averago annualized
costs of ground-water monitoring for a
MSVVLF unit accepting approximately
10 TPD oporating for 10 years would
cost about $30 per household when
annualized over 30 years ($65 per
household when annualized over only
the 10 year operating life). For landfills
accepting less than one TPD (the
Agency estimates that over one-half of
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53546 Federal Register / 'Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations
exemption :are-in this vise oategoiy),1he
average annualized cost would be about
$220 per (household when 'annualized
over 30 ysars1$450 per houaehold.lf
annualized -over only the lOyear
operating life).
The Agency believes that estimated
costs of$220 (per household forthe very
smallest communities are significant. In
the RIA for the revised criteria, the
Agency used a threshold of ilOO per
household "to identify moderate impacts.
Forthe "RIA, the Agency also looked at
a second threshold; the Agency
considered Incremental costs "that-were
greater (han one percent of median
household income as faing
"significant." 1990 Census data
indicates that median household
income acrossthe United States is
$30,000. However, EPA recognizes that
several communities have median
household incomes below the national
median. 1989 Censur data indicate that
13.1 percertt of all persons live below
poverty level. Poverty level for a three
porson household is defined as $9,900
income per year. In communities where
household incomes ere below the
national median, a $100 or higher cost
per household could be close to one
percent oT household income and thus
have a significant impact. Again, cost
figures presented here are rough
06timates using national unit costs;
labor end-equipment costs will vary per
site and may be more expensive in rural,
remote areas of the country. Also, the
Agency-assumed a specific ground-
water monitoring system of 3 or 5 wells
clusters depending on the
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Federal Register / Vol. 58, No. 189 / Friday, October 1, 1993 / Rules and Regulations 51547
(3) The compliance date for all
requirements of this part 258, unless
otherwise specified, for an existing
MSWLF unit or lateral expansion of an
existing MSWLF unit receiving flood-
related waste from federally-designated
areas within the major disasters
declared for the states of Iowa, Illinois,
Minnesota, Wisconsin, Missouri,
Nebraska, Kansas, North Dakota, and
South Dakota by the President during
the summer of 1993 pursuant to 42
U.S.C. 5121 el seq., shall be designated
by the state in which the MSWLF unit
is located in accordance with the
following:
(i) The MSWLF unit may continue to
accept waste up to April 9,1994
without being subject to part 258, if the
state in which the MSWLF unit is
located determines that the MSWLF
unit is needed to receive flood-related
waste from a fedorally-designatad
disaster area as specified in (e)(3) of this
section.
(ii) The MSWLF unit that receives an
extension under paragraph (e)(3)(i) of
this section may continue to accept
waste up to an additional six months
beyond April 9, 1994 without being
subject to part 258, if the state in which
the MSWLF unit is located determines
that the MSWLF unit is needed to
receive flood-related waste from a
federally-designated disaster area
specified in (e)(3) of this section.
(iii) In no case shall a MSWLF unit
receiving an extension under paragraph
(e)(3) (i) or (ii) of this section accept
waste beyond October 9. 1994 without
being subject to part 258.
(4) The compliance date for ell
requirements of this part 258, unless
otherwise specified, is October 9.1995
for a MSWLF unit that meets the
conditions for the exemption in
paragraph (f)(1) of this section.
(f)(1) Ownerfor operators of new
MSWLF units, existing MSWLF units,
and lateral expansions that dispose of
less than twenty (20) tons of municipal
solid waste daily, based on an annual
average, are exempt from subpart D of
this part, so long as there is no evidence
of ground-water contamination from the
MSWLF unit, and the MSWLF unit
serves:
* *
(3) If the owner or operator of a new
MSWLF unit, existing MSWLF unit, or
lateral expansion has knowledge of
ground-water contamination resulting
from the unit that has asserted the
exemption In paragraph (f)(l)(i) or
(f)(l)(>i) of this section, the owner or
oporator must notify the state Director of
such contamination and, thereafter,
comply with subpart D of this part.
*
(j) Subpart G of this part is effective
April 9,1995, except for MSWLF units
meeting the requirements of paragraph
(0(1) of this section, in which case the
effective date of subpart C is October 9,
1995.
ซ ซ
3. Section 258.2 is amended by
revising the definitions of "Existing
MSWLF unit" and "New MSWLF unit"
and by adding definitions for "Indian
lands" and "Indian tribe" to rend as
follows:
258.2 Definitions.
*
Existing MSWLF unit means any
municipal solid waste landfill unit that
is receiving solid waste as of the
appropriate dates specified in ง 258.1(e).
Waste placement in existing units must
be consistent with past operating
practices or modified practices to ensure
good management.
Indian lands,or Indian country means:
(1) All land within the li.oits of any
Indian reservation under the
jurisdiction of the United States
Government, notwithstanding the
issuance of any patent, and including
rights-of-way running throughout the
reservation;
(2) All dependent Indian communities
within the borders of the United Statos
whether within the original or
subsequently acquired territory thereof,
and whether within or without the
limits of the State; and
(3) All Indian allotments, the Indian
titles to which have not been
extinguished, including rights of way
running through the same.
Indian Tribe or Tribe means any
Indian tribe, band, nation, or
community recognized by tho Socretary
of the Interior and exercising substantial
governmental duties and powers on
Indian lands.
* * *
New MSWLF unit means any
municipal solid waste landfill unit that
has not received wasto prior to October
9,1993, or prior to October 9. 1995 if
the MSWLF unit meets the conditions of
ง 258.1(f)(1).
0
4. Section 258.50 is amended by
revising paragraph (c) introductory text,
by redesignating paragraphs (e). (f) and
(g) as paragraphs (f). (g). and (h); and by
adding paragraph (e) to read as follows.
250.50 Applicability.
(c) Owners and operators of MSWLF
units, except those meeting the
conditions of 258.1(1), must comply
with the ground-water monitoring
requirements of this part according to
the following schedule unless an
alternative schedule is specified under
paragraph (d) of this section:
(e) Owners and operators of all
MSWLF units that meet the conditions
of 258.1(f)(1) must comply with the
ground-water monitoring requirements
of this part according to the following
schedule:
(1) All MSWLF units less than two
miles from a drinking water intake
(surface or subsurface) must be in
compliance with the ground-water
monitoring requirements specified in
258.51 through 258.55 by October 9,
1995;
(2) All MSWLF units greater than two
miles from a drinking water intake
(surface or subsurface) must be in
compliance with the ground-water
monitoring requirements specified in
258.51 through 258.55 by October 9.
1996.
5. Section 258.70 is amended by
revising paragraph (b) to read as follows
ง258.70 Applicability end effective date.
ป
(b) The requirements of this section
are effective April 9,1995 except for
MSWLF units meeting the conditions of
258.1(f)(1), in which case the effective
date is October 9,1995.
6. Section 258.74 is amended by
revising paragraph (a)(5) to read as
follows:
ง 258.74 Allowable mechanisms.
(a) * *
(5) The initial payment into the trmi
fund must be made before the initial
receipt of waste or before the effective
date the requirements of this section
(April 9,1995, or October 9, 1995 for
MSWLF units meeting the conditions of
258.1(0(1)), whichever is later, in th9
case of closure and post-closure care, or
no later than 120 days after the
corrective action remedy has been
selected in accordance with the
requirements of 258.58.
*
7. Section 258.74 is amended by
revising the third sentence of paragraph
(b)(1); by revising the second sentence
of paragraph (c)(1); and by revising the
second sentence of paragraph (d)(1) to
read as follows:
-------
51548 Federal Register / Vol. 58. No. 169 / Friday. October 1. 1993 / Rules and Regulations
(b) * * *
(1) * * The bond must be effective
before the initial receipt of waste or
before the effective date of the
requirements of this section (April 9.
1995. or October 9.1995 for MSWLF
units meeting the conditions of
258.1(f)(1)), whichever is later, in the
case of closure and post-closure care, or
no later than 120 days after the
corrective action remedy has been
selected in accordance with the
requirements of ง 258.58.
# * *
(c) *
(1) * * * The letter of credit must be
effective before the initial receipt of
waste or before the effective date of the
requirements of this section (April 9,
1995, or October 9.1995 for MSWLF
units meeting the conditions of
258.1(0(1)), whichever Is later, in the
case of closure and post-closure care, or
no later than 120 days after the
corrective action remedy has been
selected in accordance with the
requirements of ง 258.58.
*
(d) * * "
(l) * * * The Insurance must be
effective before the initial receipt of
waste or before the effective date of the
requirements of this section (April 9.
1995, or October 9,1995 for MSWLF
units meeting the conditions of
258.1(f)(1)), whichever is later, in the
case of closure and post-closure care, or
no later than 120 days after the
corrective action remedy has been
selected in accordance with the
requirements of ง 258.58.
ซ * *
(FR Doc 93-24229 Filed 9-30-93: 8:45 ami
-------
53136 Federal, Register /v.Vol..J>8, NoVA197;j/(ft^^sday,,Oct.qper:J4,'l(1993t / Rules and.Regula^ipns
dealers, or traders) that provides a
reasonable basis to determine fair
market value by disseminating either
recent price quotations (including rates,
yields, or other pricing information) of
one or more identified brokers, dealers,
or traders or actual prices (including
rates, yields, or other pricing
information) of recent transactions. An
interdealer market does not include a
directory or listing of brokers, dealers,
or traders for specific contracts (such as
yellow sheets) that provides neither
price quotations nor actual prices of
recent transactions.
(ii) Debt market. A debt market exists
with respect to a debt instrument if
price quotations fox the instrument are
readily available from brokers, dealers,
or traders. A debt market does not exist
with respect to a debt instrument If
(A) No other outstanding debt
instrument of the issuer (or of any
person who guarantees the debt
instrument) is traded on an established
financial market described in paragraph
(b)(l)(i). (ii), (iii), (iv), (v), or (vi) of this
section (over traded.debt);.,
(B) .The original stated principal
amount of the issue that includes, the
debt instrument does not exceed $25,
million;
(C) The conditions and covenants
relating to the issuer'sperformance with
respect to the debt instrumentare
materially less restrictive than the
conditions and covenants included in
all of the issuer's other traded debt (e.g.,
the debt instrument is subject to an
economically significant subordination '
provision whereas the issuer's other "
traded debt is'senior); or
(D) The maturity, date of the debt
instrument is niore than 3 years after the
latest maturity date of the issuer's other
traded debt.
(c) Notional principal contracts. For
purposes of section 1092(d)
(1) A notional principal contract (as
defined in ง 1.448-3(c)(l)) constitutes
personal property, of a type thatis
actively traded if contracts ba$ed on the.
same or substantially similar specified
indices are purchased, sold, or entered
into on en established financial market
within the meaning of paragraph (b) of
this section; and,
(2) The rights and obligations of a
party to a notional principal contract are
rights and obligations with respect to
personal property and constitute an
interest in.personal property.:
(d) Effective dates. Paragraph
(b)(l)(vii) of this section applies to
positions entered into on or after
October 14,1993. Paragraph (c) of this
section applies to positions Entered into
on or after July 8,1991.
Approved: October 4,1993
Margaret Milner Richardson,
Commissioner of Internal Revenue.
Leslie Samuels,
Assistant Secretary of the Treasury.
[FR Doc. 93-25192 Filed 10-8-93; i.-zo pmj
MLLMO C00E 4S30-01-U
ENVIRONMENTAL PROTECTION
AGENCY
40 CFR Part 258
[FRL-478&-5]
Solid Waste Disposal. Facility Criteria;
Delay of the Effective Date
AGENCY: Environmental Protection
Agency (EPA).;
ACTION: Filial rulejcOiTe^ons,
summary: EPAismakiilg tedmical
corrections to theTable "Summary of
Changes to the Effective pktesofthe ;
MSWLF Criteria" which was included
in the. preamble to the final rule "Solid
Waste Disposal Facility CriteriaVDelay
of the Effective Date" that appeared, in
the Federal Register on Octoper i; 1993
(58 FR 51536). This correction notice
will amend errors that appear in the
portion of the table related to "Effective
date of ground-water monitoring and
corrective action."
EFFECTIVE DATE: October 14,1993.
FOR FURTHER INFORMATION CONTACT: Mr.
David Hockey (202) 260-7596.
SUPPLEMENTARY INFORMATION: On
October 1,1993, EPA promulgated a
final rule under Subtitle D of the
Resource Conservation and Recovery
Act and section 405 of the Clean Water'
Act delaying the effective date of the
Municipal Solid Waste Landfill Criteria
(58 FR 51536). The preamble to the rule
included a table on pages 51543 and
51544 that summarized the .effective'
dates of the final rule. That rule . _
contained minor editorial errors that-
EPA is correcting in this action. The]
corrections ara-fbr the table "Summary .
Changes to the Effective Dates of the
>WLF Criteria" for the row titled
Efective date of ground-water .
monitoringandcorrectiveactidn." For
the category of MSWLF units accepting
100 TPD or less; are not on the NPL; and
are located In a state that has submitted
an application for approval by 10/9/93:
the effective date for new units should
read October 9,1993 and not October 9,
1994. For the category of MSWLF units
that meet the small landfill exemption ฆ
in 40 CFR 258.1(f): the effective date for
existing units and lateral expansions i
should readOctober9,1995 through
October 9,199&iind notOctober 9,1996
jnly; For. the category of MSWLF units; -:
Teceivingflobd-related waste: the
effective datrforriew units should toad
October 9,1993 and not October 9;5
1994.
Correction of Publication
Accordingly, the final rule is
corrected by revising the table on pages "
51543 and 51544 to read as follows:'
SUMMARY OF CHANGES TO THE EFFECTIVE DATES' oF THE MSWLF CRITERIA i
MSWLF units ac-
cepting greater
than 100 TPD
MSWLF units ac-
cepting 100 TPD
or less; are not on
the NPL; and are
located In a statd
that has submitted
an application for'
approval by 10/9/
93
MSWLF units that
meet the small
landfill exemption
In 40 CFR
ง258.1(0
MSWLF units receiving flood-related
waste
General effective date' "
This Is the effective date for location,
operation, design, and closura/post-.
closure.
Date by which to install final cover K
cease receipt of waste by the gen-
eral effective date.
October 9,1993....
October 9,1994 -..
April 9,1994 .........
October 9,1994
October 9,1.995
October 9,1996
Up to October 9 1994 as determined
by State. J
Within one year of date,determined!^
.State; no later than;-October.:9?.
-------
Federal Register-/;Vol. 58;.No.. 197 / Thursday, October. 14, (1993 /jRules and Regulations,* 53137
Summary of Changes to the Effective Dates of the MSWLF Criteria 'Continued
MSWLF units ac-
cepting greater
than 100 TPO
MSWLF units ac-
cepting 100 TPD
or less: are not on
the NPL; and are
located In a state
that has submitted
an application for
approval by 10/9/
93
MSWLF units that
meet the small
landfill exemption
In 40 CFR
ง258.1(1)
MSWLF units receiving flood-related
waste
Effective data of ground-water mon-
itoring and corrective action.
Enectrve date of financial . assurance
requirements.-'
Prior to receipt of
waste for new
units; October 9,
1994 through ,
October 9, .1996
for existing units
and. lateral ex:' .
pahsions.
April 9,'>1995 ;v..-.;...
October 9, 1993
' for new units;
October 9; 1994.
through October'*
9, 1996 for exist-
ing units and lat-
eral expansions.'.
April 9,1995
October 9,1995
for new units;
October 9,1995
through October
v 9, '1996 for exist-
ing units and lat-
eral expansions
October 9,-1995-i.'
October 9, 1993 for new .unltsj.QctO:
bar" 9, 1994 through October. 9;
1996 for existing units and.'"lateral
expansions.
April 9.1995:
'This '
(58 fRl .
1993 Federal Reglster(58Ffl 51536) ort pages 51543 and 51544, are obsolete.
*lf a MSWLF unit reoelye&wasta anarJhJsdate.the unttmustcomolv with afl/rf Pnrt:;>ซ
s Table provtdesa sumrrwuy of the >na)of, changes: to .the e ff active dates.. Seetheflrtal rule and preamble published; On ,Octobef;j1 3.S93}
[ 51536) for"a ftj(l d'"lO-;1393:8:45 ami;
BtUJNO CODE
GENERAL SERVICES.
ADMINISTRATION
41 CFR Part 302-6
[FTR Amendment 31]
RIN 3090-AE92
Federal Travel Regulation; Increase Jn
Maximum Reimbursement Limitations
(or Real Estate Sale find Purchase
Expenses *
AGENCY: Federal Supply Service, GSA:
action: Final rulfi;
SUMMARY: This final rule amends the
Federal Travel Regulation (FTR) to
increase the maxim umdollar
limitations on reimbursement for
allowable real estate sale and purchase
expenses Incident to a change of official
station. Section 5724a(a)(4)(B) of title 5..
United States Code iequires that the
dollar limitations be updated effective
October!'of each yearmsed on the ~-
percent change; ifariyilnlhe Consumer
Price Index for AUUrbaiv Consumers,
United States City Average; Mousing -
Component, for December of the
preceding year over December. ot.Uie
second preceding year. This final rule
will have a favorable Impact on Federal-
employees authorized to relocate in the
Interest of the Government slnce.lt
increases'relocation allowance.
maximums.
EFFECTIVE DATE This final rule Is
effective October 1,1993, and applies to
employees whose effective date of
ti^nisfer is on.or.afterOctober 1,1993.
For purposes of this regulation, the -
effective dateof transfer is the date on
whi(i theemployee reports fortiutv at
thlg|iciV.offidal'
tecuttve Order122B1 orFebitiary.lTl*
wi.becauseltis notlikelyloi^e^tifav
t annualeffecton the*;ecbnoniy^f$ick)v
illiori or more; a ihajor ind^aM/in:':
costs-to consumers or otners; or*
significant adverse effects. GSA;Eas
based all adndnlstratlye decisions
underlying this rule on adequate;
information concerning the need for.
and conseauences of, this rule; has -. v
determined that the potential benefits to
society from this rule outweigh the
potential costs and has .maximized the.
net benefits; and has chosen ther
alternative approachinvplving the'least,
ฆ netcostto society/;
Listof Siulj}ectsln;41 CFR Part
ฃFoiฃUit reSsonKset put In^tfieti
'preamble, 41GFR pait302-^6 is.;
amended'as follows: -
PART 302-^6ALLOWANCE FOR
EXPENSES INCURRED IN
CONNECTION WITH RESIDENCE r
TRANSACTIONS
-ll-ma authority citation forpart302~
.6 continues to read as follows:.
. - Authority: 5 IT.S.C. 5721-5734; 20 U.S.C
905(a);.Rb: 11609, 36 FR 13747, 3 GFRT
1971-197S Comp.. d. 586.
302-6.2 [Amended],
ฃ,.Section 302-6.2 is amendedby';
removing the amount <'$20,799'V in'v:
paragraph (g)(i), and adding in its place
the amount "$21^340"; and by removing
the amount "$1Q|399". to paragraph ?
(g)(2)and addin'g'in its.pUce the amount
- Dated: September-8.V1993.*.1
RogerW.Johnion,-"
A dminlst^tordfGeneral Services,
(FR Dsfc 93^251^3^^ io4:i3^ft3: j-jttSSE
-------
-------
ATTACHMENT F
-------
53136 Federal Register /.Vol. ,58.,No. ,197 / ^Thursday,..October 14,. 1993,-/ Rules and Regulations
dealers, or traders) that provides a
reasonable basis to determine fair
market value by disseminating either
recent price quotations (including rates,
yields, or other pricing information)'of
one or more identified brokers, dealers,
or traders or actual prices (including
rates, yields, or other pricing
information) of recent transactions. An
interdealer market does not include a
directory or listing of brokers, dealers,
or traders for specific contracts (such as
yellow sheets) that provides neither
price quotations nor actual prices of
recent transactions.
(ii) Debt market. A debt market exists
with respect to a debt instrument if
price quotations for the instrument are
readily available from brokers, dealers,
or traders. A debt market does not exist
with respect to a debt instrument if.
(A) No other outstanding debt
instrument of the issuer (or of any
person who guarantees the debt -
instrument) is traded on an established
financial market described in paragraph
(b)(l)(i), (ii). (iii). (iv), (v),or (vi) of this
section (other traded.debt);, ฆ
(B) The original stated prindpal
amount of the issue that includes^the
debt instrument does not exceed $25.
million;
(C) The conditions and covenants
relating to the issuer's performance with
respect to the debt instrument are,
materially less, restrictive than the
conditions and*covenants included in
all of the issuer's other traded debt (e.g.,
the debt instrument is subject to an.
economically significant subordination
provision whereas the issuer's other
traded debt is senior); or ~
CD) The maturity date of the debt
instrument is more than 3 years after the
latest maturity date of the issuer's other
traded debt
(c) Notional principal contracts. For
purposes of section 1092(d)
(1) A notional principal contract (as
defined in ง 1.446-3(c)(l)) constitutes
personal property of a type that is .
actively traded if contracts ba?ed on the
same or substantially similar specified
indices are purchased, sold, or entered
into on an established financial market
within the meaning of paragraph (b) of
this section; and
(2) The rights and obligations of a
party to a notional principal contract are
rights and obligations with respect to
personal property and constitute an
interest in personal property.
(d) Effective dates. Paragraph
(b)(l)(vii) of this section applies to
positions entered into on or after
October 14,1993. Paragraph (c) of this
section applies to positions entered into
on or after July 8,1991.
Approved: October 4,1903
Margaret Milner Richardson,
Commissioner of Internal Revenue..
Leslie Samuels,
Assistant Secretary of the Treasury.
IFR Doc. 93-25192 Filed 10-0-43:1:26 pm)
BdlMQ COOE 4S30-01-U
ENVIRONMENTAL PROTECTION
AGENCY
40 CFR Part 258
[FRL-47885J
Solid Waste Disposal. Facility Criteria;
Delay of the Effective Date
AGENCY: Environmental Protection
Agency (EPA).
ACTION: Final rule; corrections.
SUMMARY: EPA Is making technical
corrections to the Table "Summary of
Changes to the Effective Dates of the
MSWLF Criteria" which was included
in the preamble to the final rule "Solid
Waste Disposal Facility Criteria; Delay
of the Effective Date" that appeared in
the Federal Register on October 1,1993
. (58 FR 51536). This correction notice
will amend errors that appear In the
portion of the table related to "Effective
date of ground-water monitoring and
corrective action."
EFFECTIVE DATE: October 14. 1993.
FOR FURTHER INFORMATION CONTACT: Mr.
David Hockey (202) 260-7596.
SUPPLEMENTARY INFORMATION: On
October 1,1993, EPA promulgated a
final rule under Subtitle D of the
Resource Conservation and Recovery
Act and section 405 of the Clean Water
Act delaying the effective date of the
Municipal Solid Waste Landfill Criteria
(58 FR 51536). The preamble to the rule
included a table on pages 51543 and
51544 that summarized the effective
dates of the final rule. That rule
contained minor editorial errors that
EPA is correcting in this action. The'
corrections are.for the table ''Summary
of Changes to the Effective Dates of the
MSWLF Criteria" for the row titled
"Effective dateof ground-water
monitoring and corrective action." For
the category of-MSWLF units accepting
100 TPD or less; are not on the.KPL; and
are located in a state that has submitted'
an application for approval by 10/9/93:
the effective date for new units should
read October 9,1993 and not October 9,
1994. For the category of MSWLF units
that meet the small landfill exemption
in 40 CFR 258.1(f): the effective date for.
existing units and lateral expansions
should read October 9,1995 through
October 9,1996 and not October 9,1996
only. For the category of MSWLF units
receiving flood-related waste: the
effective date for new units should tead
October 9,1993 and not October 9;
1994.
Correction of Publication
Accordingly, the final rule is
corrected by revising the table on pages
51543 and 51544 to read as follows:
Summary of Changes to the Effective Dates of the MSWLF Criteria1
General effective date'
This Is the effective date for location,
operation, design, and closure/post-,
closure.
Date by which to Install final cover M
cease receipt of waste by the gen-
era) effective data.
MSWLF units ac-
cepting greater
than 100 TPD
October 9,1993.
October 9,1994
MSWLF units ac-
cepting 100 TPD
or less; are not on
the NPU; and are
located In a state
that has submitted
an application for
approval by 10/9/
93
April 9.1994
October 9,1994.
MSWLF unfts that
meet the small
landfill exemption
In 40 CFR
ง258.1(0
October 9,1995.
October 9,1996 .
MSWLF units receiving flood-related
waste
Up to October 9,1994 as determined;
by State.
Within one year of date determined by,
State; no later than October 9;,
-------
Federal Register /^ Vol... 58; .No.. \Q7 / Thursday. October 14. ,1993 /;Rules and Regulations 53137
Summary, of changes to the Effective Dates of the MSWLF Criteria 'Continued.
MSWLF units ac-
cepting greater
than 100 TPO
MSWLF units ac-
cepting 10Q TPO
or less; are not on
the NPL; and are
located In a state
that has submitted
an application for
approval by 10/9/
93
MSWLF units that
meet the small
landfill exemption
In 40 CFR
5258.1(f)
MSWLF units receiving Rood-related
waste
Effective date of ground-water mon-
itoring and corrective action.
Effective date of financial assurance
requirements.'
Prior to receipt of
waste for new .
units; October 9,
1994 through ฆ
October 9, 1996
for existing units
'- and. lateral ex-'
' pansions.
April 9. 1995 V ' N
October 9. 1993
for new units;
October 9, 1994.
through October
9, 1996 forexist-
. ing units and lat-
eral expansions.''.
April 9,199$
October 9, 1995
for new units;
October 9, 1995
through October
< 9,1996 for exist-
ing units and lat-
era).expansions.
October Q, 1995 _.
October 9, 1993 for new units; Octo;
bar " 9, 1994 through October. 9,
1996 lor existing unlts and lateral
expansions,
April 9,19951
'This Table provides a summary of the major changes to .the effective dates-See the final rule and preamble published 6h6dtbber.1,1d93"
{S&'FR S1S36) for a full tfiscus^ion of all changes ana related conditions!" AH.other versions'of this table. Including the verslbafe] the Octobe^ii
1993'Federsf Reglซter.'(58,'FR 51536)on pages 51543'and 51544, are obsolete.'
* If a MSWLF unit receives waste after this date, the unit must comply with aO of Part 258.
Authority
EPA is promulgating these regulations
under, the authority .of sections 2002 and
4010(c) of the Resource Conservation
and Recovery Act of 1976. as amended.
42 USC 6912.
Dated: October S, 1993.
"Walter W. Kovalick, Jr.,
Acting Assistant Administrator, Office of
Solid- Waste and-Emergency Response.
(FR Doc. 03-25100 Filed "lO-t 3-93; 8:45 ami
BajJNQ COOE S5M-S0-P-
GENERAL SERVICES
ADMINISTRATION
41 CFR Part 302-6
[FTR Amendment 31]
RIN 3090-AE92
Federal Travel Regulation; Increase In
Maximum Reimbursement Limitations
for Real Estate Sale and Purchase
Expenses.'
AGENCY: Federal Supply Service, GSA. '
ACTION: Final rule. -
SUMMARY: This final rule amends the
Federal Travel Regulation (FTR) to
increase the maximum dollar
limitations on reimbursement for
allowable real estate sale and purchase
expenses Incident to a change of official
station. Section 5724a(a)(4)(B) of title 5,
United States Code requires that the
dollar limitations be updated effective
October 1; of each year Dased on the
percent change, if anyi in the Consumer
Price Index for All Urban Consumers.
United States City Average; Housing
Component, for December of the
preceding year over December of the.
second preceding year. This final rule
will have a favorable impact on Federal
employees authorized to relocate in the
interest of the Government slnce.lt
increases relocation allowance.
maximums.
effective date: This final rule is
effective October 1,' 1993, and applies to
employees whose effective date of
transfer is on or.after October 1.1993
For purposes of this regulation, the
effective date of transfer Isthe date on
which the employee reports for duty at
the new official station.-Sir
FOR FURTHER' INP^A^W tOTrrACT: Jane
E. Groat, Transportation Management^
Division (FBX), Washington; DC 20406.
telephone 703-305-5745:. ; .
SUPPLEMENTARY INFORMATION: This final
rule makes the annual adjustment to the
maximum reimbursement limitations
for the sale and purchase of an
employee's residence when the
employee transfers in the interest of the
Government. The total amount of
expenses that may be reimbursed In'
connection with the sale of a residence
shall not exceed 10 percent of the actual
sale price or $21,340, whichever is the
lesser amount The total amount of-
expenses thnt mayJierelmbursed in
connection with the purchased a .
residence shall not exceed 5 percent of
the purchase price or $10,669, ..
whichever Is the lesser amount.
The General Services Administration
(GSA) has determined that this rule Is
not a major rule for the purposes of' -
Executive Order 12291 of February 17, -
' 1981. because It is not likely to residt in
an annual effect on the economy of $100
million or more; a major Increase In
costs' to consumers or othersi or-
significant adverse effects. GSA has
based all administrative decisions
underlying this rule on adequate
information concerning the need for.
and consequences of, this rule: has .
determined that the potential benefits to
society from this rule outweigh this
potential costs and has maximized the
net benefits; and has chosen, the;
alternative approach involving the least
net cost to.sodetyA
List of Subjects ui' 41 CFR Part 302-0'
^Government empioyees^Kelocatlon
allowance's and 'entitlements. Transfers'
. For the reasons set out in^tiie' '
preamble, 41 CFR part 30JMB is
amended as follows:
PART 302-6ALLOWANCE FOR
EXPENSES INCURRED IN.
CONNECTION WITH RESIDENCE
TRANSACTIONS
vl. The authority citation for part 302-
6 continues to read as follows:
Authority: 5 U.S.C. 5721-5734; 20 U.S.C.
- 905(a): B.0.11609.36 FR 13747. 3 CFR.
19711975 Comp.. p. 586.
302-6.2 [Amended]
2. Section 302-6.2 is amended by
removing the amount "$20,709" in-
paragraph (g)(1), and adding in its place
the amount "$21,340"; and by romoving
the amount "$10,399" In paragraph
(g)(2) and adding in its place the amount:
"$10,669".
Dated: September 8.1993.
Roger W. Johnson,
Administrator 6f General Services.
(FR Doc. 93-25183 Filed 10-13-^3; 8;45aml
-------
-------
ATTACHMENT G
-------
ง 256.62
agency determines there is sufficient
interest.
Cc) The State shall comply with the
requirements of Office of Manage-
ment and Budget Circular No. A-95.
(d) Copies of the final work program
shall be placed in the State informa-
tion depositories maintained under
ง 256.60(a)(2).
ง 256.62 Requirements for public partici-
pation in State regulatory development.
(a) The State shall conduct public
hearings (and public meetings where
the State determines there is suffi-
cient interest) on State legislation and
regulations, in accord with the State
administrative procedures act, to solic-
it reactions and recommendations. Fol-
lowing the public hearings, a respon-
siveness summary shall be prepared
and made available to the public in
accord with 40 CFR 25.8.
(b) In advance of the hearings and
meetings required by paragraph (a) of
this section, the State shall prepare a
fact sheet on proposed regulations^or
legislation, mail the fact sheet to agen-
cies, organizations and individuals on
the list maintained under
ง 256.60(a)(1) and place the fact sheet
in the State information depositories
maintained under ง 256.60(a)(2).
ง 256.63 Requirements for public partici-
pation in the permitting of facilities.
(a) Before approving a permit appli-
cation (or renewal of a permit) for a
resource recovery or solid waste dis-
posal facility the State shall hold a
public hearing to solicit public reac-
tion and recommendations on the pro-
posed permit application if the State
determines there is a significant,
degree of public interest in the pro-
posed permit.
(b) This hearing shall be held in
accord with 40 CFR 25.5.
ง 256.64 Requirements for public partici-
pation in the open dump inventory.
(a) The State shall provide an oppor-
tunity for public participation prior to
submission of any classification of a
facility as an open dump to the Feder-
al Government. The State shall ac-
complish this by providing notice as
specified in ง 256.64(b) or by using
other State administrative procedures
40 CFR Ch. I (7-1-92 Edition)
which provide equivalent public Da
ticipation. r"
(b) The State may satisfy the re
quirement of ง 256.64(a) by providing
written notice of the availability 0j
the results of its classifications to all
parties on the list required under
ง 256.60(a)(1) at least 30 days before
initial submission of these classifica-
tions to the Federal Government. For
those parties on the list required
under ง 256.60(a)(1) who are owners or
operators of facilities classified as
open dumps, such notice shall indicate
that the facility has been so classified.
[46 FR 47052, Sept. 23, 1981)
ง 256.65 Recommendations for public par-
ticipation.
(a) State and substate planning
agencies should establish an advisory
group, or . utilize an existing group, to
provide recommendations on major
policy and program decisions. The ad-
visory group's membership should re-
flect a balanced viewpoint in accord
with 40 CFR 25.7(c).
(b) State and substate planning
agencies should develop public educa-
tion programs designed to encourage
informed public participation in the
development and implementation of
solid waste management plans.
[44 PR 45079, July 31. 1979. Redesignated
and amended at 46 PR 47052, Sept. 23, 1981]
PART 257CRITERIA FOR CLASSIFI-
CATION OF SOLID WASTE DISPOS-
AL FACILITIES AND PRACTICES
Sec.
257.1 Scope and purpose.
257.2 Definitions.
257.3 Criteria for classification of solid
waste disposal facilities and practices.
257.3-1 Floodplains.
257.3-2 Endangered species.
257.3-3 Surface water.
257.3-4 Ground water.
257.3-5 Application to land used for the
production of food-chain crops (interim
final).
257.3-6 Disease.
257.3-7 Air.
257.3-8 Safety.
257.4 Effective date.
Appendix I to Part 257Maximum Con-
taminant Levels (MCLs)
-------
ง 257.3
40 CFR Ch. I (7-1-92 Edition)
Open dump means a facility for the
disposal of solid waste which does not
comply with this part.
Practice means the act of disposal of
solid waste.
Sanitary landfill means a facility for
the disposal of solid waste which com-
plies with this part.
Sludge means any solid, semisolid, or
liquid waste generated from a munici-
pal, commercial, or industrial
wastewater treatment plant, water
supply treatment plant, or air pollu-
tion control facility or any other such
waste having similar characteristics
and effect.
Solid waste means any garbage,
refuse, sludge from a waste treatment
plant, water supply treatment plant,
or air pollution control facility and
other discarded material, including
solid, liquid, semisolid, or contained
gaseous material resulting from indus-
trial, commercial, mining, and agricul-
tural operations, and from community
activities, but does not include solid or
dissolved materials in domestic
sewage, or solid or dissolved material
in irrigation return flows or industrial
discharges which are point sources
subject to permits under section 402 of
the Federal Water Pollution Control
Act, as amended (86 Stat. 880), or
source, special nuclear, or byproduct
material as defined by the Atomic
Energy Act of 1954, as amended (68
Stat. 923).
State means any of the several
States, the District of Columbia, the
Commonwealth of Puerto Rico, the
Virgin Islands, Guam, American
Samoa, and the Commonwealth of the
Northern Mariana Islands.
[44 FR 53460, Sept. 13, 1979; 44 FR 58910,
Oct. 12, 1979; 56 FR 51016, Oct. 9, 1991]
Effective Date Note; At 56 FR 51016. Oct.
9. 1991. ง 257.2 revised the definition for "fa-
cility". and added definitions for "land ap-
plication unit," "landfill," "municipal solid
waste landfill unit," "surface impound-
ment," and "waste pile", effective October 9,
1993. For the convenience of the user, the
revised and added text is set forth below;
ง 257.2 Definitions.
ซ ป
Facility means all contiguous land and
structures, other appurtenances, and im-
provements on the land used for the dispos-
al of solid waste.
* ซ
Land application unit means an area
where wastes are applied onto or incorporat-
ed into the soil surface (excluding manure
spreading operations) for agricultural pur-
poses or for treatment and disposal.
Landfill means an area of land or an exca-
vation in which wastes are placed for per-
manent disposal, and that is not a land ap-
plication unit, surface impoundment, injec-
tion well, or waste pile.
* ป +
Municipal solid waste landfill (MSWLF)
unit means a discrete area of land or an ex-
cavation that receives household waste, and
that is not a land application unit, surface
impoundment, injection well, or waste pile,
as those terms are defined in this section. A
MSWLF unit also may receive other types
of RCRA Subtitle D wastes, such as com-
mercial solid waste, nonhazardous sludge,
and industrial solid waste. Such a landfill
may be publicly or privately owned. An
MSWLF unit may be a new MSWLF unit,
an existing MSWLF unit or a lateral expan-
sion.
*
Surface impoundment or impoundment
means a facility or part of a facility that is a
natural topographic depression, human-
made excavation, or diked area formed pri-
marily of earthern materials (although it
may be lined with human-made materials),
that is designed to hold an accumulation of
liquid wastes or wastes containing free liq-
uids and that is not an injection well. Exam-
ples of surface impoundments are holding
storage, settling, and aeration pits, ponds,
and lagoons.
Waste pile or pile means any noncontain-
erized accumulation of solid, nonflowing
waste that is used for treatment or storage.
ง257.3 Criteria for classification of solid
waste disposal facilities and practices.
Solid waste disposal facilities or
practices which violate any of the fol-
lowing criteria pose a reasonable prob-
ability of adverse effects on health or
the environment:
ง 257.3-1 Floodplains.
(a) Facilities or practices in flood-
plains shall not restrict the flow of the
base flood, reduce the temporary
water storage capacity of the flood-
-------
Environmental Protection Agency
Diairi. or result in washout of solid
vvaste, so as to pose a hazard to human
jjfe< wildlife, or land or water re-
sources.
(b) As used in this section:
(1) Based flood means a flood that
has a 1 percent or greater chance of
recurring in any year or a flood of a
magnitude equalled or exceeded once
in 100 years on the average over a sig-
nificantly long period.
(2) Floodplain means the lowland
and relatively flat areas adjoining
inland and coastal waters, including
flood-prone areas of offshore islands,
which are inundated by the base flood.
(3) Washout means the carrying
away of solid waste by waters of the
base flood.
[44 FR 53460, Sept. 13. 1979; 44 FR 54708,
Sept. 21. 1979]
ง 257.3-2 Endangered species.
(a) Facilities or practices shall not
cause or contribute to the taking of
any endangered or threatened species
of plants, fish, or wildlife.
(b) The facility or practice shall not
result in the destruction or adverse
modification of the critical habitat of
endangered or threatened species as
identified in 50 CFR Part 17.
(c) As used in this section:
(1) Endangered or threatened species
means any species listed as such pur-
suant to section 4 of the Endangered
Species Act.
(2) Destruction or adverse modifica-
tion means a direct or indirect alter-
ation of critical habitat which appre-
ciably diminishes the likelihood of the
survival and recovery of threatened or
endangered species using that habitat.
(3) Taking means harassing, harm-
ing, pursuing, hunting, wounding, kill-
ing, trapping, capturing, or collecting
or attempting to engage in such con-
duct.
ง 257.3-3 Surface water. .
(a) For purposes of section 4004(a)
of the Act, a facility shall not cause a
discharge of pollutants into waters of
the United States that is in violation
of the requirements of the National
Pollutant Discharge Elimination
System (NPDES) under section 402 of
the Clean Water Act, as amended.
ง 257.3-4
of section 4004(a)
discharge o? ri^iltyJshal1 not cause a
material to watS? or fill
States that is in vioi^f the United
quirements under sectilฐn ฐf the re"
Clean Water Act! asamended 4 thฐ
(c) A facility or practice shall not
cause non-point source pollution of
waters of the United States that vio-
lates applicable legal requirements im-
plementing an areawide or Statewide
water quality management plan that
has been approved by the Administra-
tor under section 208 of the Clean
Water Act, as amended.
(d) Definitions of the terms "Dis-
charge of dredged material". "Point
source". "Pollutant", "Waters of the
United States", and "Wetlands" can be
found in the Clean Water Act, as
amended, 33 U.S.C. 1251 et seq., and
implementing regulations, specifically
33 CFR Part 323 (42 FR 37122, July
19, 1977).
[44 FR 53460, Sept. 13, 1979, as amended at
46 FR 47052. Sept. 23. 1981]
ง 257.3-4 Ground water.
(a) A facility or practice shall not
contaminate an underground drinking
water source beyond the solid waste
boundary or beyond an alternative
boundary specified in accordance with
paragraph (b) of this section.
(b)(1) For purposes of section
1008(a)(3) of the Act or section 405(d)
of the CWA, a party charged with
open dumping or a violation of section
405(e) may demonstrate that compli-
ance should be determined at an alter-
native boundary in lieu of the solid
waste boundary. The court shall estab-
lish such an alternative boundary only
if it finds that such a change would
not result in contamination of ground
water which may be needed or used
for human consumption. This finding
shall be based on analysis and consid-
eration of all of the following factors
that are relevant:
(i) The hydrogeological characteris-
tics of the facility and surrounding
land, including any natural attenu-
ation and dilution characteristics of
the aquifer.
-------
ง 257.3-5
40 CFR Ch. I (7-1-92 Edition)
(ii) The volume and physical and
chemical characteristics of the leach-
ate;
(iii) The quantity, quality, and direc-
tion of flow of ground water underly-
ing the facility;
(iv) The proximity and withdrawal
rates of ground-water users;
(v) The availability of alternative
drinking water supplies;
(vi) The existing quality of the
ground water, including other sources
of contamination and their cumulative
impacts on the ground water;
(vii) Public health, safety, and wel-
fare effects.
(2) For purposes of sections 4004(a)
and 1008(a)(3), the State may estab-
lish an alternative boundary for a fa-
cility to be used in lieu of the solid
waste boundary only if it finds that
such a change would not result in the
contamination of ground water which
may be needed or used for human con-
sumption. Such a finding shall be
based on an analysis and consideration
of all of the factors identified in para-
graph (b)(1) of this section that are
relevant.
(c) As used in this section:
(1) Aquifer means a geologic forma-
tion, group of formations, or portion
of a formation capable of yielding
usable quantities of ground water to
wells or springs.
(2) Contaminate means introduce a
substance that would cause:
(i) The concentration of that sub-
stance in the ground water to exceed
the maximum contaminant level speci-
fied in Appendix I, or
(ii) An increase in the concentration
of that substance in the ground water
where the existing concentration of
that substance exceeds the maximum
contaminant level specified in Appen-
dix I.
(3) Ground water means water below
the land surface in the zone of satura-
tion.
(4) Underground drinking water
source means:
(i) An aquifer supplying drinking
water for human consumption, or
(ii) An aquifer in which the ground
water contains less than 10,000 mg/1
total dissolved solids.
(5) Solid waste boundary means the
outermost perimeter of the solid waste
(projected in the horizontal plane) ^
it would exist at completion of the dis.
posal activity.
[44 FR 53460, Sept. 13, 1979, as amended at
46 FR 47052. Sept. 23. 1981]
ง 257.3-5 Application to land used for the
production of food-chain crops (inter-
im final).
(a) Cadmium. A facility or practice
concerning application of solid waste
to within one meter (three feet) of the
surface of land used for the produc-
tion of food-chain crops shall not exist
or occur, unless in compliance with all
requirements of paragraphs (a)(1) (i)
through (iii) of this section or all re-
quirements of paragraphs (a)(2) (i)
through (iv) of this section.
(l)(i) The pH of the solid waste and
soil mixture is 6.5 or greater at the
time of each solid waste application,
except for solid waste containing cad-
mium at concentrations of 2 mg/kg
(dry weight) or less.
(ii) The annual application of cadmi-
um from solid waste does not exceed
0.5 kilograms per hectare (kg/ha) on
land used for production of tobacco,
leafy vegetables or root crops grown
for human consumption. For other
food-chain crops, the annual cadmium
application rate does not exceed:
Annual Cd
Time period
application
rate (kg/
ha)
Present to June 30, 1984
2.0
July 1. 1984 to December 31. 1986
1 25
Beginning January 1, 1987
0.5
(iii) The cumulative application of
cadmium from solid waste does not
exceed the levels in either paragraph
(a)(l)(iii)(A) or (B) of this section.
(A)
Soil cation exchange capacity
(meq/100g)
Maximum cumulative
application (kg/ha)
Back-
ground soil
pH less
than 6.5
Back-
ground soil
pH more
than 6 5
Less than 5
5
5
5 to 15
5
10
More than 15
5
20
-------
ฃrlvironmenปal Protection Agency
,g) For soils with a background pH
f jgss than 6.5. the cumulative cadmi-
0 application rate does not exceed
the levels below: Provided, That the
u of the solid waste and soil mixture
P aCjjusted to and maintained at 6.5 or
greater whenever food-chain crops are
grown.
ง 257.3-6
Maximum
So>: cation exchange capacity (meq/lOOg) ! gp^at'on
(kg/ha)
Less than 5.
5 to 15
More than 15..
5
10
20
Pasture crฐPs- forage.
and
(2)(i) The only food-chain crop pro-
duced is animal feed.
(ii) The pH of the solid waste and
soil mixture is 6.5 or greater at the
time of solid waste application or at
the time the crop is planted, whichev-
er occurs later, and this pH level is
maintained whenever food-chain crops
are grown.
(iii) There is a facility operating
plan which demonstrates how the
animal feed will be distributed to pre-
clude ingestion by humans. The facili-
ty operating plan describes the meas-
ures to be taken to safeguard against
possible health hazards from cadmium
entering the food chain, which may
result from alternative land uses.
(iv) Future property owners are noti-
fied by a stipulation in the land record
or property deed which states that the
property has received solid waste at
high cadmium application rates and
that food-chain crops should not be
grown, due to a possible health
hazard.
(b) Poly chlorinated Biphenyls
(PCBs). Solid waste containing concen-
trations of PCBs equal to or greater
than 10 mg/kg (dry weight) is incorpo-
rated into the soil when applied to
land used for producing animal feed,
including pasture crops for animals
raised for milk. Incorporation of the
solid waste into the soil is not required
if it is assured that the PCB content is
less than 0.2 mg/kg (actual weight) in
animal feed or less than 1.5 mg/kg (fat
basis) in milk.
(c) As used in this section:
(1) Animal feed means any crop
grown for consumption by animals,
pH2ofBth?sor?r1or0to the the
substances that alter the hvdr1^ ฐf
concentration. V^rogen ion
(3) Cation exchange capacity means
the sum of exchangeable cations a soil
can absorb expressed in milli-equiva
lents per 100 grams of soil as deter-
mined by sampling the soil to the
depth of cultivation or solid waste
placement, whichever is greater, and
analyzing by the summation method
for distinctly acid soils or the sodium
acetate method for neutral, calcareous
or saline soils ("Methods of Soil Anal-
ysis, Agronomy Monograph No. 9." C.
A. Black, ed., American Society of
Agronomy. Madison, Wisconsin, pp
891-901, 1965).
(4) Food-chain crops means tobacco,
crops grown for human consumption,
and animal feed for animals whose
products are consumed by humans.
(5) Incorporated into the soil means
the injection of solid waste beneath
the surface of the soil or the mixing of
solid waste with the surface soil.
(6) Pasture crops means crops such
as legumes, grasses, grain stubble and
stover which are consumed by animals
while grazing.
(7) pH means the logarithm of the
reciprocal of hydrogen ion concentra-
tion.
(8) Root crops means plants whose
edible parts are grown below the sur-
face of the soil.
(9) Soil pH is the value obtained by
sampling the soil to the depth of culti-
vation or solid waste placement,
whichever is greater, and analyzing by
the electrometric method. ("Methods
of Soil Analysis, Agronomy Mono-
graph No. 9," C.A. Black, ed., Ameri-
can Society of Agronomy. Madison,
Wisconsin, pp. 914-926, 1965.)
[44 FR 53460. Sept. 13. 1979; 44 FR 54708,
Sept. 21. 1979]
ง 257.3-6 Disease.
(a) Disease Vectors. The facility or
practice shall not exist or occur unless
the on-site population of disease vec-
tors is minimized through the periodic
application of cover material or other
-------
ง 257.3-7
techniques as appropriate so as to pro-
tect public health.
(b) Sewage sludge and septic tank
pumpings (Interim Final). A facility
or practice involving disposal of
sewage sludge or septic tank pumpings
shall not exist or occur unless in com-
pliance with paragraphs (b) (1), (2) or
(3) of this section.
(1) Sewage sludge that is applied to
the land surface or is incorporated
into the soil is treated by a Process to
Significantly Reduce Pathogens prior
to application or incorporation. Public
access to the facility is controlled for
at least 12 months, and grazing by ani-
mals whose products are consumed by
humans is prevented for at least one
month. Processes to Significantly
Reduce Pathogens are listed in Appen-
dix II. Section A. (These provisions do
not apply to sewage sludge disposed of
by a trenching or burial operation.)
(2) Septic tank pumpings that are
applied to the land surface or incorpo-
rated into the soil are treated by a
Process to Significantly Reduce
Pathogens (as listed in Appendix II,
Section A), prior to application or in-
corporation, unless public access to
the facility is controlled for at least 12
months and unless grazing by animals
whose products are consumed by
humans is prevented for at least one
month. (These provisions do not apply
to septic tank pumpings disposed of by
a trenching or burial operation.)
(3) Sewage sludge or septic tank
pumpings that are applied to the land
surface or are incorporated into the
soil are treated by a Process to Fur-
ther Reduce Pathogens, prior to appli-
cation or incorporation, if crops for
direct human consumption are grown
within 18 months subsequent to appli-
cation or incorporation. Such treat-
ment is not required if there is no con-
tact between the solid waste and the
edible portion of the crop; however, in
this case the solid waste is treated by a
Process to Significantly Reduce
Pathogens, prior to application; public
access to the facility is controlled for
at least 12 months; and grazing by ani-
mals whose products are consumed by
humans is prevented for at least one
month. If crops for direct human con-
sumption are not grown within 18
months of application or incorpora-
40 CFR Ch. I (7-1-92 Ediซ0fl)
tion, the requirements of paraer*
(b) (1) and (2) of this section aoni
Processes to Further Reduce Path
gens are listed in Appendix II. Spph
B. CUc>n
(c) As used in this section:
(1) Crops for direct human consumn
tion means crops that are consumed
by humans without processing to mini
mize pathogens prior to distribution to
the consumer.
(2) Disease vector means rodents
flies, and mosquitoes capable of trans-
mitting disease to humans.
(3) Incorporated into the soil means
the injection of solid waste beneath
the surface of the soil or the mixing of
solid waste with the surface soil.
(4) Periodic application of cover ma-
terial means the application and com-
paction of soil or other suitable mate-
rial over disposed solid waste at the
end of each operating day or at such
frequencies and in such a manner as to
reduce the risk of fire and to impede
vectors access to the waste.
(5) Trenching or burial operation
means the placement of sewage sludge
or septic tank pumpings in a trench or
other natural or man-made depression
and the covering with soil or other
suitable material at the end of each
operating day such that the wastes do
not migrate to the surface.
[44 PR 53460. Sept. 13. 1979; 44 FR 54708,
Sept. 21. 1979]
ง 257.3-7 Air.
(a) The facility or practice shall not
engage in open burning of residential,
commercial, institutional or industrial
solid waste. This requirement does not
apply to infrequent burning of agricul-
tural wastes in the field, silvicultural
wastes for forest management pur-
poses. land-clearing debris, diseased
trees, debris from emergency clean-up
operations, and ordnance.
(b) For purposes of section 4004(a)
of the Act, the facility shall not vio-
late applicable requirements developed
under a State Implementation Plan
(SIP) approved or promulgated by the
Administrator pursuant to section 110
of the Clean Air Act, as amended.
(c) As used in this section "open
burning" means the combustion of
solid waste without (1) control of com-
-------
gnvironmen*al Protection Agency
tion air to maintain adequate tem-
bUrature for efficient combustion, (2)
Pentainment of the combustion reac-
C
-------
Ft. 257, App. I, Note
" Temperature 1 degrees
Fahrenheit
53 7 and below
53.8 to 58.3 ....
58 4 to 63 8 ... .
63.9 to 70 6
70.7 to 79.2 ....
79 3 to 90 5 . ...
Degrees Celsius
12 and below
12.1 to 14.6...
14.7 to 17 6 .
17 7 to 21.4 .
21.5 to 26.2..
26.3 to 32.5
Level
(milligrams
per liter)
24
2.2
20
1.8
1.6
1.4
1 Annual average of the maximum daily air temperature
2. Maximum contaminant levels for or-
ganic chemicals. The following are the max-
imum contaminant levels for organic chemi-
cals:
(a) Chlorinated hydrocarbons:
Endrm (1,2,3,4,10,10-Hexachloro-6,7-epoxy-
1,4,4a,5,6,7,8,8a-octahydro-1.4-endo.
endo-5,8-dimethano naphthalene)
Lindane (1,2,3.4,5,6-Hexachlorocyclo-
hexane, gamma isomer
Methoxychlor (1,1,1-Tnchloro-2.2-bis (p-
methoxyphenyl) ethane)
Toxaphene (C,.H10CI.-Technical chlorinated
camphene, 67 to 69 percent chlorine)
(b) Chlorophenoxys'
2.4-D (2.4-Dichlorophenoxy-acetic acid)
2.4.5-TP Silvex (2.4.5-Tnchlorophen- oxy-
propionic acid)
Level
(milligrams
per liter)
0.0002
0.004
0.1
0.005
0.1
0.01
40 CFR Ch. I (7-1-92 Editi0ri)
3. Maximum microbiological contaminant
levels. The maximum contaminant level for
coliform bacteria from any one well is as fol-
lows:
(a) using the membrane filter technique:
(1) Four coliform bacteria per 100 millili-
ters if one sample is taken, or
(2) Four coliform bacteria per 100 millili-
ters in more than one sample of all the sam-
ples analyzed in one month.
(b) Using the five tube most probable
number procedure, (the fermentation tube
method) in accordance with the analytical
recommendations set forth in "Standard
Methods for Examination of Water and
Waste Water", American Public Health As-
sociation, 13th Ed. pp. 662-688, and using a
Standard sample, each portion being one
fifth of the sample:
(1) If the standard portion is 10 milliliters,
coliform in any five consecutive samples
from a well shall not be present in three or
more of the 25 portions, or
(2) If the standard portion is 100 millili-
ters, coliform in any five consecutive sam-
ples from a well shall not be present in five
portions in any of five samples or in more
than fifteen of the 25 portions.
4. Maximum contaminant levels for
radium-226, radium-228, and gross alpha
particle radioactivity. The following are the
maximum contaminant levels for radium-
ra.
226, radium-228, and gross alpha particl
dioactivity: e
(a) Combined radium-226 and radi
228-5 pCi/1; Utn*
(b) Gross alpha particle activity (inclu
-------
gflvironmental Protection Agency
Pt. 257, App. II
nimum of three months is needed, two
011 nths of which temperatures average on a
"2," basis above 0- C.
Anaerobic digestion: The process is con-
ducted in the absence of air at residence
ta\es ranging from 60 days at 20* C to 15
Hays at 35" to 55* C. with a volatile solids re-
duction of at least 38 percent.
Composting: Using the within-vessel.
static aerated pile or windrow composting
methods, the solid waste is maintained at
minimum operating conditions of 40* C for 5
days. For four hours during this period the
temperature exceeds 55* C.
Lime Stabilization: Sufficient lime is
added to produce a pH of 12 after 2 hours of
contact.
Other methods: Other methods or operat-
ing conditions may be acceptable if patho-
gens and vector attraction of the waste
(volatile solids) are reduced to an extent
equivalent to the reduction achieved by any
of the above methods.
B. Processes to Further Reduce Pathogens
Composting: Using the within-vessel com-
posting method, the solid waste is main-
tained at operating conditions of 55' C or
greater for three days. Using the static aer-
ated pjle composting method, the solid-
waste is'maintained at operating conditions
of 55* C or greater for three days. Using the
windrow composting method, the solid
waste attains a temperature of 55* C or
greater for at least 15 days during the com-
posting period. Also, during the high tem-
perature period, there will be a minimum of
five turnings of the windrow.
Heat drying: Dewatered sludge cake is
dried by direct or indirect contact with hot
gases, and moisture content is reduced to 10
percent or lower. Sludge particles reach
temperatures well in excess of 80" C, or the
wet bulb temperature of the gas stream in
contact with the sludge at the point where
it leaves the dryer is in excess of 80" C.
Heat treatment: Liquid sludge is heated to
temperatures of 180" C for 30 minutes.
Thermophilic Aerobic Digestion: Liquid
sludge is agitated with air or oxygen to
maintain aerobic conditions at residence
times of 10 days at 55-60" C, with a volatile
solids reduction of at least 38 percent.
Other methods: Other methods or operat-
ing conditions may be acceptable if patho-
gens and vector attraction of the waste
(volatile solids) are reduced to an extent
equivalent to the reduction achieved by any
of the above methods.
Any of the processes listed below, if added
to the processes described in Section A
above, further reduce pathogens. Because
the processes listed below, on their own, do
not reduce the attraction of disease vectors,
they are only add-on in nature.
Beta ray irradiation: Sludge is irradiated
with beta rays from an accelerator at dos-
ages of at least 1.0 megarad at room temper-
ature (ca. 20* C).
Gamma ray irradiation: Sludge is Irradi-
ated with gamma rays from certain isotopes,
such as "Cobalt and '"Cesium, at dosages
of at least 1.0 megarad at room temperature
(ca. 20* C).
Pasteurization: Sludge is maintained for
at least 30 minutes at a minimum tempera-
ture of 70" C.
Other methods: Other methods or operat-
ing conditions may be acceptable if patho-
gens are reduced to ah extent equivalent to
the reduction achieved by any of the above
add-on methods.
PART 258CRITERIA FOR MUNICI-
PAL SOLID WASTE LANDFILLS (Eff.
10-9-93)
Subpart AGeneral
Sec.
258.1 Purpose, scope, and applicability.
258.2 Definitions.
258.3 Consideration of other Federal laws.
258.4258.9 '[Reserved]
Subpart BLocation Restrictions
258.10 Airport safety.
258.11 Floodplains.
258.12 Wetlands.
258.13 Fault areas.
258.14 Seismic impact zones.
258.15 Unstable areas.
258.16 Closure of existh.D municipal solid
waste landfill units.
258.17258.19 [Reserved]
Subpart COperating Criteria
258.20 Procedures for excluding the receipt
of hazardous waste.
258.21 Cover material requirements.
258.22 Disease vector control.
258.23. Explosive gases control.
258.24 Air criteria.
258.25 Access requirements.
258.26 Run-on/run-off control systems.
258.27 Surface water requirements.
258.28 Liquids restrictions.
258.29 Recordkeeping requirements.
258.30258.39 [Reserved]
Subpart DDesign Criteria
258.40 Design criteria.
258.41258.49 [Reserved]
Subpart EGround-Water Monitoring and
Corrective Action
258.50 Applicability.
258.51 Ground-water monitoring systems.
-------
ง 258.1
Sec.
258.53 Ground water sampling and analy-
sis requirements.
258.54 Detection monitoring program.
258.55 Assessment monitoring program.
258.56 Assessment of corrective measures.
258.57 Selection of remedy.
258.58 Implementation of the corrective
action program.
258.59 [Reserved]
Subpart FCloture and Post-closure Care
258.60 Closure criteria.
258.61 Post-closure care requirements.
258.62-258.69 [Reserved]
Subpart GFinancial Assurance Criteria
258.70 Applicability and effective date.
258.71 Financial assurance for closure.
258.72 Financial assurance for post-closure
care.
258.73 Financial assurance for corrective
action.
258.74 Allowable mechanisms.
Appendix I to Part 258Constituents for
Detection Monitoring
Appendix II to Part 258List of Hazard-
ous and Organic Constituents
Authority: 42 U.S.C. 6907(a)(3), 6944(a)
and 6949(c); 33 U.S.C. 1345 (d) and (e).
Source: 56 FR 51016, Oct. 9, 1991, unless
otherwise noted.
Effective Date Note: At 56 FR 51016,
Oct. 9, 1991, part 258 was added, effective
October 9, 1993, except subpart G, which is
effective April 9, 1994.
Subpart AGeneral
ง 258.1 Purpose, scope, and applicability.
(a) The purpose of this part is to es-
tablish minimum national criteria
under the Resource Conservation and
Recovery Act (RCRA or the Act), as
amended, for all municipal solid waste
landfill (MSWLF) units and under the
Clean Water Act, as amended, for mu-
nicipal solid waste landfills that are
used to dispose of sewage sludge.
These minimum national criteria
ensure the protection of human
health and the environment.
(b) These Criteria apply to owners
and operators of new MSWLF units,
existing MSWLF units, and lateral ex-
pansions, except as otherwise specifi-
cally provided In this part; all other
solid waste disposal facilities and prac-
tices that are not regulated under Sub-
title C of RCRA are subject to the cri-
40 CFR Ch. I (7-1-92 Ediปj0n)
teria contained in part 257 of
chapter. Ms
(c) These Criteria do not apply
municipal solid waste landfill uni;ฐ
that do not receive waste after Opl
ber 9, 1991. ctฐ-
(d) MSWLF units that receive wast
after October 9. 1991 but stop receiv
ing waste before October 9, 1993 ar
exempt from all the requirements of
this part 258, except the final cover re-
quirement specified in ง 258.60(a). The
final cover must be installed within six
months of last receipt of wastes.
Owners or operators of MSWLF units
described in this paragraph that fail to
complete cover installation within this
six month period will be subject to all
the requirements of this part 258,
unless otherwise specified.
(e) All MSWLF units that receive
waste on or after October 9, 1993 must
comply with all requirements of this
part 258 unless otherwise specified.
(f)(1) Owners or operators of new
MSWLF uhits, existing MSWLF units,
and lateral expansions that dispose of
less than twenty (20) tons of munici-
pal solid waste daily, based on an
annual average are exempt from sub-
parts D and E of this part, so long as
there is no evidence of existing
ground-water contamination from the
MSWLF unit, and the MSWLF unit
serves;
(1) A community that experiences an
annual interruption of at least three
consecutive months of surface trans-
portation that prevents access to a re-
gional waste management facility, or
(ii) A community that has no practi-
cable waste management alternative
and the landfill unit is located in an
area that annually receives less than
or equal to 25 inches of precipitation.
(2) Owners or operators of new
MSWLF units, existing MSWLF units,
and lateral expansions that meet the
criteria in paragraph. (fXIXi) or
(f)(l)(ii) of this section must place in
the operating record information dem-
onstrating this.
(3) If the owner or operator of a new
MSWLF unit, existing MSWLF unit,
or lateral expansion has knowledge of
ground-water contamination resulting
from the unit that has asserted the ex-
emption in paragraph (f)(l)(i) or
(fXIXii) of this section, the owner or
-------
Environmental Protection Agency
operator must notify the State Direc-
tor of such contamination and, there-
after. comply with subparts D and E
0f this part.
(g) Municipal solid waste landfill
units failing to satisfy these criteria
are considered open dumps for pur-
poses of State solid waste management
planning under RCRA.
(h) Municipal solid waste landfill
units failing to satisfy these criteria
constitute open dumps, which are pro-
hibited under section 4005 of RCRA.
(i) Municipal solid waste landfill
units containing sewage sludge and
failing to satisfy these Criteria violate
sections 309 and 405(e) of the Clean
Water Act.
(j) The effective date of this part is
October 9, 1993, except subpart G of
this part 258 is effective April 9, 1994.
ง 258.2 Definitions.
Unless otherwise noted, all terms
contained in this part, are defined by
their plain meaning. This section con-
tains"definitions for terms that appear
throughout this part; additional defi-
nitions appear in the specific sections
to which they apply.
Active life means the period of oper-
ation beginning with the initial receipt
of solid waste and ending at comple-
tion of closure activities in accordance
with ง 258.60 of this part.
Active portion means that part of a
facility or unit that has received or is
receiving wastes and that has not been
closed in accordance with ง 258.60 of
this part.
Aquifer means a geological forma-
tion, group of formations, or porton of
a formation capable of yielding signifi-
cant quantities of ground water to
wells or springs.
Commercial solid waste means all
types of solid waste generated by
stores, offices, restaurants, ware-
houses, and other nonmanufacturing
activities, excluding residential and in-
dustrial wastes.
Director of an approved State means
the chief administrative officer of a
State agency responsible for imple-
menting the State municipal solid
waste permit program or other system
of prior approval that is deemed to be
adequate by EPA under regulations
ง 258.2
published pursuant to sections 2002
and 4005 of RCRA.
Existing MSWLF unit means any
municipal solid waste landfill unit that
is receiving solid waste as of the effec-
tive date of this part (October 9, 1993).
Waste placement in existing units
must be consistent with past operating
practices or modified practices to
ensure good management.
Facility means all contiguous land
and structures, other appurtenances,
and improvements on the land used
for the disposal of solid waste.
Ground water means water below
the land surface in a zone of satura-
tion.
Household waste means any solid
waste (including garbage, trash, and
sanitary waste in septic tanks) derived
from households (including single and
multiple residences, hotels and motels,
bunkhouses. ranger stations, crew
quarters, campgrounds, picnic
grounds, ' and day-use recreation
areas).
Industrial solid waste means solid
waste generated by manufacturing or
industrial processes that is not a haz-
ardous waste regulated under subtitle
C of RCRA. Such waste may include,
but is not limited to. waste resulting
from the following manufacturing
processes: Electric power generation;
fertilizer/agricultural chemicals; food
and related products/by-products; in-
organic chemicals; iron and steel man-
ufacturing; leather and leather prod-
ucts; nonferrous metals manufactur-
ing/foundries; organic chemicals; plas-
tics and resins manufacturing; pulp
and paper industry; rubber and miscel-
laneous plastic products; stone, glass,
clay, and concrete products; textile
manufacturing: transportation equip-
ment; and water treatment. This term
does not include mining waste or oil
and gas waste.
Lateral expansion means a horizon-
tal expansion of the waste boundaries
of an existing MSWLF unit.
Leachate means a liquid that has
passed through or emerged from solid
waste and contains soluble, suspended,
or miscible materials removed from
such waste.
Municipal solid waste landfill unit
means a discrete area of land or an ex-
-------
ง 258.3
40 CFR Ch. I (7-1-92 Edition)
waste, and that is not a land applica-
tion unit, surface impoundment, injec-
tion well, or waste pile, as those terms
are defined under ง 257.2. A MSWLF
unit also may receive other types of
RCRA subtitle D wastes, such as com-
mercial solid waste, nonhazardous
sludge, conditionally exempt small
quantity generator waste and industri-
al solid waste. Such a landfill may be
publicly or privately owned. A
MSWLF unit may be a new MSWLF
unit, an existing MSWLF unit or a lat-
eral expansion.
New MSWLF unit means any munic-
ipal solid waste landfill unit that has
not received waste prior to the effec-
tive date of this part (October 9, 1993).
Open burning means the combustion
of solid waste without:
(1) Control of combustion air to
maintain adequate temperature for ef-
ficient combustion,
(2) Containment of the combustion
reaction in an enclosed device to pro-
vide sufficient residence time and
mixing for complete combustion, and
(3) Control of the emission of the
combustion products.
Operator means the personCs) re-
sponsible for the overall operation of a
facility or part of a facility.
Owner means the personCs) who
owns a facility or part of a facility.
Run-off means any rainwater, leach-
ate, or other liquid that drains over
land from any part of a facility.
Run-on means any rainwater, leach-
ate, or other liquid that drains over
land onto any part of a facility.
Saturated zone means that part of
the earth's crust in which all voids are
filled with water.
Sludge means any solid, semi-solid,
or liquid waste generated from a mu-
nicipal. commercial, or industrial
wastewater treatment plant, water
supply treatment plant, or air pollu-
tion control facility exclusive of the
treated effluent from a wastewater
treatment plant.
Solid waste means any garbage, or
refuse, sludge from a wastewater treat-
ment plant, water supply treatment
plant, or air pollution control facility
and other discarded material, includ-
ing solid, liquid, semi-solid, or con-
tained gaseous material resulting from
industrial, commercial, mining, and ag-
ricultural operations, and from com-
munity activities, but does not include
solid or dissolved materials in domestic
sewage, or solid or dissolved materials
in irrigation return flows or industrial
discharges that are point sources sub-
ject to permit under 33 U.S.C. 1342, or
source, special nuclear, or by-product
material as defined by the Atomic
Energy Act of 1954, as amended (68
Stat. 923).
State means any of the several
States, the District of Columbia, the
Commonwealth of Puerto Rico, the
Virgin Islands, Guam, American
Samoa, and the Commonwealth of the
Northern Mariana Islands.
State Director means the chief ad-
ministrative officer of the State
agency responsible for implementing
the State municipaLsolid waste permit
program or other system of prior ap-
proval.
Uppermost aquifer means the geo-
logic formation nearest the natural
ground surface that is an aquifer, as
well as. lower aquifers that are hy-
draulically interconnected with this
aquifer within the facility's property
boundary.
Waste management unit boundary
means a vertical surface located at the
hydraulically downgradient limit of
the unit. This vertical surface extends
down into the uppermost aquifer.
[56 FR 51016, Oct. 9. 1991: 57 PR 28627,
June 26, 1992]
ง258.3 Consideration of other Federal
laws.
The owner or operator of a munici-
pal solid waste landfill unit must
comply with any other applicable Fed-
eral rules, laws, regulations, or other
requirements.
งง258.4258.9 [Reserved!
Subpart BLocation Restrictions
ง 258.10 Airport safety.
(a) Owners or operators of new
MSWLF units, existing MSWLF units,
and lateral expansions that are locat-
ed within 10,000 feet (3,048 meters) of
any airport runway end used by turbo-
jet aircraft or within 5,000 feet (1.524
meters) of any airport runway end
-------
gnvironmental Protection Agency
ed by only piston-type aircraft must
demonstrate that the units are de-
fine d and operated so that the
jtfSWLF unit does not pose a bird
Hazard to aircraft.
(b) Owners or operators proposing to
site new MSWLF units and lateral ex-
tensions within a five-mile radius of
a,ny airport runway end used by turbo-
jet or piston-type aircraft must notify
the affected airport and the Federal
aviation Administration (FAA).
(c) The owner or operator must
place the demonstration in paragraph
(a) of this section in the operating
record and notify the State Director
that it has been placed in the operat-
ing record.
(d) For purposes of this section:
(1) Airport means public-use airport
open to the public without prior per-
mission and without restrictions
within the physical capacities of avail-
able facilities.
(2) Bird hazard means an increase in
the likelihood of bird/aircraft colli-
sions that may cause damage to the
aircraft or injury to its occupants.
ง258.11 Floodplains.
(a) Owners or operators of new
MSWLF units, existing MSWLF units,
and lateral expansions located in 100-
year floodplains must demonstrate
that the unit will not restrict the flow
of the 100-year flood, reduce the tem-
porary water storage capacity of the
floodplain, or result in washout of
solid waste so as to pose a hazard to
human health and the environment.
The owner or operator must place the
demonstration in the operating record
and notify the State Director that it
has been placed in the operating
record.
(b) For purposes of this section:
(1) Floodplain means the lowland
and relatively flat areas adjoining
inland and coastal waters, including
flood-prone areas of offshore islands,
that are inundated by the 100-year
flood.
(2) 100-year flood means a flood that
has a 1-percent or greater chance of
recurring in any given year or a flood
of a magnitude equalled or exceeded
once in 100 years on the average over
a significantly long period.
ง 258.12
(3) Washout means the carrvinir
sEnSjrwaste by
ง 258.12 Wetlands.
(a) New MSWLF units and lateral
expansions shall not be located in wet-
lands, unless the owner or operator
can make the following demonstra-
tions to the Director of an approved
State:
(1) Where applicable under section
404 of the Clean Water Act or applica-
ble State wetlands laws, the presump-
tion that practicable alternative to the
proposed landfill is available which
does not involve wetlands is clearly re-
butted;
(2) The construction and operation
of the MSWLF unit will' not:
(i) Cause or contribute to violations
of any applicable State water quality
standard,
(ii) Violate, any applicable toxic ef-
fluent standard or prohibition under
Section 307 of the Clean Water Act,
(iii) Jeopardize the continued exist-
ence of endangered or threatened spe-
cies or result in the destruction or ad-
verse modification of a critical habitat,
protected under the Endangered Spe-
cies Act of 1973, and
(iv) Violate any requirement under
the Marine Protection, Research, and
Sanctuaries Act of 1972 for the protec-
tion of a marine sanctuary:
(3) The MSWLF unit will not cause
or contribute to significant degrada-
tion of wetlands. The owner or opera-
tor must demonstrate the integrity of
the MSWLF unit and its ability to pro-
tect ecological resources by addressing
the following factors:
(i) Erosion, stability, and migration
potential of native wetland soils, muds
and deposits used to support the
MSWLF unit;
(ii) Erosion, stability, and migration
potential of dredged and fill materials
used to support the MSWLF unit;
(iii) The volume and chemical
nature of the waste managed in the
MSWLF unit;
(iv) Impacts on fish, wildlife, and
other aquatic resources and their habi-
tat from release of the solid waste;
(v) The potential effects of cata-
-------
ง258.13
land and the resulting impacts on the
environment; and
(vi) Any additional factors, as neces-
sary, to demonstrate that ecological
resources in the wetland are suffi-
ciently protected.
(4) To the extent required under sec-
tion 404 of the Clean Water Act or ap-
plicable State wetlands laws, steps
have been taken to attempt to achieve
no net loss of wetlands (as defined by
acreage and function) by first avoiding
impacts to wetlands to the maximum
extent practicable as required by para-
graph (a)(1) of this section, then mini-
mizing unavoidable impacts to the
maximum extent practicable, and fi-
nally offsetting remaining unavoidable
wetland impacts through all appropri-
ate and practicable compensatory miti-
gation actions (e.g., restoration of ex-
isting degraded wetlands or creation of
man-made wetlands): and
(5) Sufficient information is avail-
able to make a reasonable determina-
tion with respect to these demonstra-
tions!
(b) For purposes of this section, wet-
lands means those areas that are de-
fined in 40 CFR 232.2(r).
ง 258.13 Fault areas.
(a) New MSWLF units and lateral
expansions shall not be located within
200 feet (60 meters) of a fault that has
had displacement in Holocene time
unless the owner or operator demon-
strates to the Director of an approved
State that an alternative setback dis-
tance of less than 200 feet (60 meters)
will prevent damage to the structural
integrity of the MSWLF unit and will
be protective of human health and the
environment.
(b) For the purposes of this section:
(1) Fault means a fracture or a zone
of fractures in any material along
which strata on one side have been
displaced with respect to that on the
other side.
(2) Displacement means the relative
movement of any two sides of a fault
measured in any direction.
(3) Holocene means the most recent
epoch of the Quaternary period, ex-
tending from the end of the Pleisto-
cene Epoch to the present.
40 CFR Ch. I (7-1-92 Edซtj0|<)
ง 258.14 Seismic impact zones.
(a) New MSWLF units and later
expansions shall not be located in Seia*
mic impact zones, unless the owner
operator demonstrates to the DirectX
of an approved State/Tribe that an
containment structures. include
liners, leachate collection systems, and
surface water control systems, are de-
signed to resist the maximum horizon"
tal acceleration in lithified earth ma-
terial for the site. The owner or opera-
tor must place the demonstration in
the operating record and notify the
State Director that it has been placed
in the operating record.
(b) For the purposes of this section:
(1) Seismic .impact zone means an
area with a ten percent or greater
probability that the. maximum hori-
zontal acceleration'in lithified earth
material, expressed as a percentage of
the earth's gravitational pull (g), will
exceed 0.10g in 250 years.
(2) Maximum horizontal accelera-
tion in lithified earth material means
the maximum expected horizontal ac-
celeration depicted on a seismic
hazard map, with a 90 percent or
greater probability that the accelera-
tion will not be exceeded in 250 years,
or the maximum expected horizontal
acceleration based on a site-specific
seismic risk assessment.
(3) Lithified earth material means
all rock, including all naturally occur-
ring and naturally formed aggregates
or masses of minerals or small parti-
cles of older rock that formed by crys-
tallization of magma or by induration
of loose sediments. This term does not
include man-made materials, such as
fill, concrete, and asphalt, or uncon-
solidated earth materials, soil, or rego-
lith lying at or near the earth surface.
[56 FR 51016, Oct. 9. 1991: 57 FR 28627,
June 26. 1992]
ง 258.15 Unstable areas.
(a) Owners or operators of new
MSWLF units, existing MSWLF units,
and lateral expansions located in an
unstable area must demonstrate that
engineering measures have been incor-
porated into the MSWLF unit's design
to ensure that the integrity of the
structural components of the MSWLF
unit will not be disrupted. The owner
-------
gnvifฐnnien*a' Pro*ec*ion Agency
ง 258.20
operator must place the demonstra-
tion in the operating record and notify
Le state Director that it has been
oiaced in the operating record. The
owner or operator must consider the
following factors, at a minimum, when
determining whether an area is unsta-
ble:
(1) On-site or local soil conditions
that may result in significant differen-
tial settling;
(2) On-site or local geologic or geo-
morphologic features; and
(3) On-site or local human-made fea-
tures or events (both surface and sub-
surface).
(b) For purposes of this section:
(1) Unstable area means a location
that is susceptible to natural or
human-induced events or forces capa-
ble of impairing the integrity of some
or all of the landfill structural compo-
nents responsible for preventing re-
leases from a landfill. Unstable areas
can include poor foundation condi-
tions, areas susceptible to mass, move-
ments, and Karst terranes.
(2) Structural components means
liners, leachate. collection systems,
final covers, run-on/run-off systems,
and any other component used in the
construction and operation of the
MSWLF that is necessary for protec-
tion of human health and the environ-
ment.
(3) Poor foundation conditions
means those areas where features
exist which indicate that a natural or
man-induced event may result in inad-
equate foundation support for the
structural components of an MSWLF
unit.
(4) Areas susceptible to mass move-
ment means those areas of influence
(i.e., areas characterized as having an
active or substantial possibility of
mass movement) where the movement
of earth material at, beneath, or adja-
cent to the MSWLF unit, because of
natural or man-induced events, results
in the downslope transport of soil and
rock material by means of gravitation-
al influence. Areas of mass movement
include, but are not limited to, land-
slides, avalanches, debris slides and
flows, soil fluction, block sliding, and
rock fall.
(5) Karst terranes means areas
where karst topography, with its char-
acteristic surface and subterranean
features, is developed as the result of
dissolution of limestone, dolomite or
other soluble rock. Characteristic phy-
siographic features present in karst
terranes include, but are not limited
to. sinkholes, sinking streams, caves,
large springs, and blind valleys.
ง 258.16 Closure of existing municipal
solid waste landfill units.
(a) Existing MSWLF units that
cannot make the demonstration speci-
fied in ง 258.10(a), pertaining to air-
ports, ง 258.11(a), pertaining to flood-
plains. or ง 258.15(a), pertaining to un-
stable areas, must close, by October 9,
1996, in accordance with ง 258.60 of
this part and conduct post-closure ac-
tivities in accordance j^ith ง 258.61 of
this part.
(b) The deadline for closure required
by paragraph (a) of this section may
be extended, up to two years if the
owner or operator demonstrates to the
Director of an approved State that:
(1) There is no available alternative
disposal capacity;
(2) There is no immediate threat to
human health and the environment.
Note to Subpart B: Owners or operators
of MSWLFs should be aware that a State in
which their landfill is located or is to be lo-
cated, may have adopted a state wellhead
protection program in accordance with sec-
tion 1428 of the Safe Drinking Water Act.
Such state wellhead protection programs
may impose additional requirements on
owners or operators of MSWLFs than those
set forth in this part.
งง258.17258.19 [Reserved]
Subpart COperating Criteria
ง 258.20 Procedures for excluding the re-
ceipt of hazardous waste.
(a) Owners or operators of all
MSWLF units must implement a pro-
gram at the facility for detecting and
preventing the disposal of regulated
hazardous wastes as defined in part
261 of this chapter and polychlorinat-
ed biphenyls (PCB) wastes as defined
in part 761 of this chapter. This pro-
gram must include, at a minimum:
(1) Random inspections of incoming
loads unless the owner or operator
-------
ง 258.21
coming loads do not contain regulated
hazardous wastes or PCB wastes;
(2) Records of any inspections;
(3) Training of facility personnel to
recognize regulated hazardous waste
and PCB wastes; and
(4) Notification of State Director of
authorized States under Subtitle C of
RCRA or the EPA Regional Adminis-
trator if in an unauthorized State if a
regulated hazardous waste or PCB
waste is discovered at the facility.
(b) For purposes of this section, reg-
ulated hazardous waste means a solid
waste that is a hazardous waste, as de-
fined in 40 CFR 261.3, that is not ex-
cluded from regulation as a hazardous
waste under 40 CFR 261.4(b) or was
not generated by a conditionally
exempt small quantity generator as
defined in ง 261.5 of this chapter.
ง 258.21 Cover material requirements.
(a) Except as provided in paragraph
(b) of this section, the owners or oper-
ators of all MSWLF units must cover
disposed solid waste with six inches .of
earthen material at the end of each
operating day, or at more frequent in-
tervals if necessary, to control disease
vectors, fires, odors, blowing litter, and
scavenging.
Cb) Alternative materials of an alter-
native thickness (other than at least
six inches of earthen material) may be
approved by the Director of an ap-
proved State if the owner or operator
demonstrates that the alternative ma-
terial and thickness control disease
vectors, fires, odors, blowing litter, and
scavenging without presenting a
threat to human health and the envi-
ronment.
(c) The Director of an approved
State may grant a temporary waiver
from the requirement of paragraph (a)
and (b) of this section if the owner or
operator demonstrates that there are
extreme seasonal climatic conditions
that make meeting such requirements
impractical.
ง258.22 Disease vector control.
(a) Owners or operators of all
MSWLF units must prevent or control
on-site populations of disease vectors
using techniques appropriate for the
protection of human health and the
environment.
40 CFR Ch. I (7-1
(b) For purposes of this secti0n
ease vectors means any rodents^*-
mosquitoes, or other animals, i'n i es-
ing insects, capable of transmit '
disease to humans.
ง 258.23 Explosive gases control.
(a) Owners or operators 0f
MSWLF units must ensure that: al1
(1) The concentration of methan
gas generated by the facility does not
exceed 25 percent of the lower expio
sive limit for methane in facility struc
tures (excluding gas control or recov-
ery system components); and
(2) The concentration of methane
gas does not exceed the lower explo-
sive limit for methane at the facility
property boundary.
(b) Owners or operators of all
MSWLF units must implement a rou-
tine methane monitoring program to
ensure that the standards of para-
graph (a) of this section are met.
(1) The type and frequency of moni-
toring must be determined based on
the following factors:
(1) Soil conditions;
(ii) The hydrogeologic conditions
surrounding the facility;
(iii) The hydraulic conditions sur-
rounding the facility; and
(iv) The location of facility struc-
tures and property boundaries.
(2) The minimum frequency of mon-
itoring shall be quarterly.
(c) If methane gas levels exceeding
the limits specified in paragraph (a) of
this section are detected, the owner or
operator must:
(1) Immediately take all necessary
steps to ensure protection of human
health and notify the State Director;
(2) Within seven days of detection,
place in the operating record the
methane gas levels detected and a de-
scription of the steps taken to protect
human health; and
(3) Within 60 days of detection, im-
plement a remediation plan for the
methane gas releases, place a copy of
the plan in the operating record, and
notify the State Director that the plan
has been implemented. The plan shall
describe the nature and extent of the
problem and the proposed remedy.
(4) The Director of an approved
State may establish alternative sched-
-------
^ironmental Protection Agency
for demonstrating compliance
$th paragraphs (c) (2) and (3) of this
se.Cjj0rpฐr purposes of this section.
\ner explosive limit means the lowest
10 rcent by volume of a mixture of ex-
Pfosive gases in air that will propagate
a flame at 25*C and atmospheric pres-
sure.
ง 258.24 Air criteria.
(a) Owners or operators of all
j^SWLFs must ensure that the units
n0t violate any applicable require-
ments developed under a State Imple-
mentation Plan (SIP) approved or pro-
mulgated by the Administrator pursu-
ant to section 110 of the Clean Air Act,
as amended.
(b) Open burning of solid waste,
except for the infrequent burning of
agricultural wastes, silvicultural
wastes, landclearing debris, diseased
trees, or debris from emergency clean-
up operations, is prohibited at all
MSWLF units.
ง 258.25 Access requirements.
Owners or operators of all MSWLP
units must control public access and
prevent unauthorized vehicular traffic
and illegal dumping of wastes by using
artificial barriers, natural barriers, or
both, as appropriate to protect human
health and the environment.
ง 258.26 Run-on/run-off control systems.
(a) Owners or operators of all
MSWLF units must design, construct,
and maintain:
(1)A run-on control system to pre-
vent flow onto the active portion of
the landfill during the peak discharge
from a 25-year storm;
(2) A run-off control system from
the active portion of the landfill to
collect and control at least the water
volume resulting from a 24-hour, 25-
year storm.
(b) Run-off from the active portion
of the landfill unit must be handled in
accordance with ง 258.27(a) of this
part.
(56 FR 51016. Oct. 9. 1991: 57 PR 28627.
June 26. 1992]
ง 258.27 Surface water requirements.
MSWLF units shall not:
ง 258.28
into watens of^h h ฐf Pollutants
eluding wetlands, tha^viofafes^5, in"
Q,U H?mentS of the Clean Water Ac? ฆ*'
eluding, but not limited to tvflป !:ln"
al Pollutant Discharge ' ElimSฐn"
System (NPDES) requirements pursฐu
ant to section 402. p rsu~
(b) Cause the discharge of a non-
point source of pollution to waters of
the United States, including wetlands,
that violates any requirement of an
area-wide or State-wide water quality
management plan that has been ap-
proved under section 208 or 319 of the
Clean Water Act, as amended.
ง 258.28 Liquids restrictions.
(a) Bulk or noncontainerized liquid
waste may not be placed in MSWLF
units unless:
(1) The waste is household waste
other than septic waste; or
(2) The waste is leachate or gas con-
densate derived from the MSWLF unit
and the MSWLF unit, whether it is a
new or existing MSWLF, or lateral ex-
pansion, is designed with a composite
liner and leachate collection system as
described in ง 258.40(a)(2) of this part.
The owner or operator must place the
demonstration in the operating record
and notify the State Director that it
has been placed in the operating
record.
(b) Containers holding liquid waste
may not be placed in a MSWLF unit
unless:
(1) The container is a small contain-
er similar in size to that normally
found in household waste;
(2) The container is designed to hold
liquids for use other than storage; or
(3) The waste is household waste.
(c) For purposes of this section:
(1) Liquid waste means any waste
material that is determined to contain
"free liquids" as defined by Method
9095 (Paint Filter Liquids Test), as de-
scribed in "Test Methods for Evaluat-
ing Solid Wastes, Physical/Chemical
Methods" (EPA Pub. No. SW-846).
(2) Gas condensate means the liquid
generated as a result of gas recovery
-------
ง 258.29
ง 258.29 Recordkeeping requirements.
(a) The owner or operator of a
MSWLF unit must record and retain
near the facility in an operating
record or in an alternative location ap-
proved by the Director of an approved
State the following information as it
becomes available:
(1) Any location restriction demon-
stration required under subpart B of
this part;
(2) Inspection records, training pro-
cedures. and notification procedures
required in ง 258.20 of this part;
(3) Gas monitoring results from
monitoring and any remediation plans
required by ง 258.23 of this part;
(4) Any MSWLF unit design docu-
mentation for placement of leachate
or gas condensate in a MSWLF unit as
required under ง 258.28(a)(2) of this
part;
(5) Any demonstration, certification,
finding, monitoring, testing, or analyt-
ical data required by subpart E of this
part;
(6) Closure and post-closure care
plans and any monitoring, testing, or
analytical data as required by
งง 258.60 and 258.61 of this part; and
(7) Any cost estimates and financial
assurance documentation required by
subpart G of this part.
(8) Any information demonstrating
compliance with small community ex-
emption as required by ง 258.1(f)(2).
(b) The owner/operator must notify
the State Director when the docu-
ments from paragraph (a) of this sec-
tion have been placed or added to the
operating record, and all information
contained in the operating record
must be furnished upon request to the
State Director or be made available at
all reasonable times for inspection by
the State Director.
(c) The Director of an approved
State can set alternative schedules for
recordkeeping and notification re-
quirements as specified in paragraphs
(a) and (b) of this section, except for
the notification requirements in
ง 258.10(b) and ง 258.55
-------
gnvironinen,al Protection Agency
/ciVXiF unit. In determining the rele-
point of compliance State Direc-
V r shall consider at least the follow-
factors:
(1) ^y^rogeologic characteris-
tic 0f the facility and surrounding
l3(2) The vo^ume an^ physical and
chemical characteristics of the leach-
ate!
(3) The quantity, quality, and direc-
tion, of flow of ground water;
(4) The proximity and withdrawal
rate of the ground-water users;
(5) The availability of alternative
drinking water supplies;
(6) The existing quality of the
ground water, including other sources
of contamination and their cumulative
impacts on the ground water, and
whether the ground water is currently
used or reasonably expected to be used
for drinking water;
(7) Public health, safety, and welfare
effects; and
(8) Practicable capability. of the
owneror operator.
(e) If EPA does not promulgate a
rule establishing the procedures and
requirements for State compliance
with RCRA section 4005(c)(1)(B) by
October 9, 1993, owners and operators
in unapproved States may utilize a
design meeting the performance
standard in ง 258.40(a)(1) if the follow-
ing conditions are met:
(1) The State determines the design
meets the performance standard in
ง 258.40(a)(1);
(2) The State petitions EPA to
review its determination; and
(3) EPA approves the State determi-
nation or does not disapprove the de-
termination within 30 days.
Note to subpart D: 40 CPR part 239 is re-
served to establish the procedures and re-
quirements for State compliance with
RCRA section 4005(c)(1)(B).
Table 1
ง 258.50
Table 1Continued
Chemical
Arsenic
Barium
Benzene
Cadmium
Carbon tetrachloride
Chromium (hexavalent)
2 4-Dichlorophenoxy acotic acid.
MCL
(mg/l)
0.05
1.0
0.005
0.01
0.005
0 05
0 1
Chemical
1,4-Oichtorobeniene
t .2-Otchloroelhane
1.1 -Oichlor oethylene
Endrin
Fluonde
Lindane
Lead
Mercury
Methoxychlor
Nitrate
Selenium
Srfver
Toxaphene..
1,1,1 -Trichtorome thane
T richloroethytene
2.4,5-Trichlorophenoxy acetic acid
Vinyl CMonde
Subpart E-Ground-Water Monitoring
and Corrective Action
ง 258.50 Applicability.
(a) The requirements in this part
apply to MSWLF units, except as pro-
vided in paragraph (b) of this section.
(b) Ground-water monitoring re-
quirements under ง 258.51 through
ง 258.55 of this part may be suspended
by the Director of an approved State
for a MSWLF unit if the owner or op-
erator can demonstrate that there is
no potential for migration of hazard-
ous constituents from that MSWLF
unit to the uppermost aquifer (as de-
fined in ง 258.2) during the active life
of the unit and the post-closure care
perjod. This demonstration must be
certified by a qualified ground-water
scientist and approved by the Director
of an approved State, and must be
based upon:
(1) Site-specific field collected meas-
urements, sampling, and analysis of
physical, chemical, and biological
processes affecting contaminant fate
and transport, and
(2) Contaminant fate and transport
predictions that maximize contami-
nant migration and consider impacts
on human health and environment.
(c) Owners and operators of MSWLF
units must comply with the ground-
water monitoring requirements of this
part according to the following sched-
-------
ง 258.50
specified under paragraph (d) of this
section:
(1) Existing MSWLF units and later-
al expansions less than one mile from
a drinking water intake (surface or
subsurface) must be in compliance
with the ground-water monitoring re-
quirements specified in งง 258.51-
258.55 by October 9, 1994;
(2) Existing MSWLF units and later-
al expansions greater than one mile
but less than two miles from a drink-
ing water intake (surface or subsur-
face) must be in compliance with the
ground-water monitoring require-
ments specified in งง 258.51-258.55 by
October 9. 1995;
(3) Existing MSWLF units and later-
al expansions greater than two miles
from a drinking water intake (surface
or subsurface) must be in compliance
with the ground-water monitoring re-
quirements specified in งง 258.51-
258.55 by October 9, 1996.
(4) New MSWLF units must be in
compliance with the ground-water
monitoring requirements specified in
งง 258.51-258.55 before waste can be
placed in the unit.
(d) The Director of an approved
State may specify an alternative
schedule for the owners or operators
of existing MSWLF units and lateral
expansions to comply with the
ground-water monitoring require-
ments specified in งง 258.51-258.55.
This schedule must ensure that 50 per-
cent of all existing MSWLF units are
in compliance by October 9, 1994 and
all existing MSWLF units are in com-
pliance by October 9, 1996. In setting
the compliance schedule, the Director
of an approved State must consider
potential risks posed by the unit to
human health and the environment.
The following factors should be con-
sidered in determining potential risk;
(1) Proximity of human and environ-
mental receptors;
(2) Design of the MSWLF unit;
(3) Age of the MSWLF unit;
(4) The size of the MSWLF unit; and
(5) Types and quantities of wastes
disposed including sewage sludge; and
(6) Resource value of the underlying
aquifer, including;
(I) Current and future uses;
(ii) Proximity and withdrawal rate
of users; and
40 CFR Ch. I (7-Uon
'Ort)
(iii) Ground-water quality and
tity.
(e) Once established at a
unit, ground-water monitoring shaM*
conducted throughout the active Vbe
and post-closure care period of tufe
MSWLF unit as specified in ง 258.61 1
(f) For the purposes of this subPart
a qualified ground-water scientist is
scientist or engineer who has received
a baccalaureate or Post-graduate
degree in the natural sciences or engi-
neering and has sufficient training
and experience in groundwater hydrol-
ogy and related fields as may be dem-
onstrated by State registration, profes-
sional Certifications, or completion of
accredited university programs that
enable that individual to make sound
professional judgements regarding
ground-water monitoring, contami-
nant fate and transport, and correc-
tive-action.
(g) The Director of an approved
State may establish alternative sched-
ules for demonstrating compliance
with ง 258.51(d)(2), pertaining to noti-
fication of placement of certification
in operating record; ง 258.54(c)(1), per-
taining to notification that statistical-
ly significant increase (SSI) notice is
in operating record; ง 258.54(c) (2) and
(3), pertaining to an assessment moni-
toring program; ง 258.55(b), pertaining
to sampling and analyzing Appendix II
constituents; ง 258.55(d)(1), pertaining
to placement of notice (Appendix II
constituents detected) in record and
notification of notice in record;
ง 258.55(d)(2), pertaining to sampling
for appendix I and II to this part;
ง 258.55(g), pertaining to notification
(and placement of notice in record) of
SSI above ground-water protection
standard; งง 258.55(g)(l)(iv) and
258.56(a), pertaining to assessment of
corrective measures; ง 258.57(a), per-
taining to selection of remedy and no-
tification of placement in record;
ง 258.58(c)(4), pertaining to notifica-
tion of placement in record (alterna-
tive corrective action measures): and
ง 258.58(f), pertaining to notification
of placement in record (certification of
remedy completed).
[56 FR 51016, Oct. 9. 1991; 57 FR 28628.
June 26, 1992]
-------
gnV{ronmental Protection Agency
ง 258.51 Ground-water monitoring sys-
tems.
(a) A ground-water monitoring
system must be installed that consists
f a sufficient number of wells, in-
stalled at appropriate locations and
depths, to yield ground-water samples
from the uppermost aquifer (as de-
fined in ง 258.2) that:
(1) Represent the quality of back-
ground ground water that has not
been affected by leakage from a unit.
A determination of background qual-
ity may include sampling of wells that
are not hydraulically upgradient of
the waste management area where:
(1) Hydrogeologic conditions do not
allow the owner or operator to deter-
mine what wells are hydraulically up-
gradient; or
(ii) Sampling at other wells will pro-
vide an indication of background
ground-water quality that is as repre-
sentative or more representative than
that provided by the upgradient wells;
and
(2). Represent the quality of ground
water passing the relevant point of
compliance specified by Director of an
approved State under ง 258.40(d) or at
the waste management unit boundary
in unapproved States. The downgra-
dient monitoring system must be in-
stalled at the relevant point of compli-
ance specified by the Director of an
approved State under ง 258.40(d) or at
the waste management unit boundary
in unapproved States that ensures de-
tection of ground-water contamination
in the uppermost aquifer. When physi-
cal obstacles preclude installation of
ground-water monitoring wells at the
relevant point of compliance at exist-
ing units, the down-gradient monitor-
ing system may be installed at the
closest practicable distance hydrauli-
cally down-gradient from the relevant
point of compliance specified by the
Director of an approved State under
ง 258.40 that ensure detection of
groundwater contamination in the up-
permost aquifer.
(b) The Director of an approved
State may approve a multiunit
ground-water monitoring system in-
stead of separate ground-water moni-
toring systems for each MSWLF unit
when the facility has several units,
provided the multi-unit ground-water
ง 258.51
ment^M 258y?ie^ meets the re<^re-
iiieiiL OI ง 258.51(a) and will be nc r
tective of human health and th?envT
ronment as individual monitoring syl
terns for each MSWLP unit, based on
the following factors:
(1) Number, spacing, and orientation
of the MSWLF units;
(2) Hydrogeologic setting;
(3) Site history;
(4) Engineering design of the
MSWLF units, and
(5) Type of waste accepted at the
MSWLF units.
(c) Monitoring wells must be cased
in a manner that maintains the integ-
rity of the monitoring well bore hole.
This casing must be screened or perfo-
rated and packed with gravel or sand,
where necessary, to enable collection
of ground-water samplesrThe annular
space (i.e.. the space between the bore
hole and well casing) above the sam-
pling depth must be sealed to prevent
contamination 'of samples and the
ground water.
(1) The owner or operator must
notify the State Director that the
design, installation, development, and
decommission of any monitoring wells,
piezometers and other measurement,
sampling, and analytical devices docu-
mentation has been placed in the op-
erating record; and
(2) The monitoring wells, piezo-
meters, and other measurement, sam-
pling, and analytical devices must be
operated and maintained so that they
perform to design specifications
throughout the life of the monitoring
program.
(d) The number, spacing, and depths
of monitoring systems shall be:
(1) Determined based upon site-spe-
cific technical information that must
include thorough characterization of:
(i) Aquifer thickness, ground-water
flow rate, ground-water flow direction
including seasonal and temporal fluc-
tuations in ground-water flow; and
(ii) Saturated and unsaturated geo-
logic units and fill materials overlying
the uppermost aquifer, materials com-
prising the uppermost aquifer, and
materials comprising the confining
unit defining the lower boundary of
the uppermost aquifer; including, but
not limited to: Thicknesses, stratigra-
-------
ง 258.53
ities, porosities and effective porosi-
ties.
(2) Certified by a qualified ground-
water scientist or approved by the Di-
rector of an approved State. Within 14
days of this certification, the owner or
operator must notify the State Direc-
tor that the certification has been
placed in the operating record.
ง258.52 (Reserved)
ง 258.53 Ground-water sampling and anal-
ysis requirements.
(a) The ground-water monitoring
program must include consistent sam-
pling-and analysis procedures that are
designed to ensure monitoring results
that provide an accurate representa-
tion of ground-water quality at the
background and downgradient wells
installed in compliance with
ง 258.51(a) of this part. The owner or
operator must notify the State Direc-
tor that the sampling and analysis
program documentation has been
placed in the operating record and the
program must include procedures and
techniques for:
(1) Sample collection;
(2) Sample preservation and ship-
ment;
(3) Analytical procedures;
(4) Chain of custody control; and
(5) Quality assurance and quality
control.
(b) The ground-water monitoring
program must include sampling and
analytical methods that are appropri-
ate for ground-water sampling and
that accurately measure hazardous
constituents and other monitoring pa-
rameters in ground-water samples.
Ground-water samples shall not be
field-filtered prior to laboratory analy-
sis.
(c) The sampling procedures and fre-
quency must be protective of human
health and the environment.
(d) Ground-water elevations must be
measured in each well immediately
prior to purging, each time ground
water is sampled. The owner or opera-
tor must determine the rate and direc-
tion of ground-water flow each time
ground water is sampled. Ground-
water elevations in wells which moni-
tor the same waste management area
must be measured within a period of
40 CFR Ch. I (7-1-92 Edv
time short enough to avoid tern,,
variations in ground-water flow
could preclude accurate determinat-^
of ground-water flow rate and hi 11
tion. lrec-
(e) The owner or operator must
tablish background ground-water qi.^"
ity in a hydraulically upgradient
background welKs) for each of nf
monitoring parameters or constituent
required in the particular ground
water monitoring program that an
plies to the MSWLP unit, as deter-
mined under ง 258.54(a) or ง 258.55(aj
of this part. Background ground-water
quality may be established at wells
that are not located hydraulically up.
gradient from the MSWLP unit if it
meets the requirements of
ง 258.51(a)(1).
(f) The number of samples collected
to establish ground-water quality data
must be consistent with the appropri-
ate statistical procedures determined
pursuant to paragraph (g) of this sec-
tion. The sampling procedures shall be
those specified under ง 258.54(b) for
detection monitoring, ง 258.55 (b) and
(d) for assessment monitoring, and
ง 258.56(b) of corrective action.
(g) The owner or operator must
specify in the operating record one of
the following statistical methods to be
used in evaluating ground-water moni-
toring data for each hazardous constit-
uent. The statistical test chosen shall
be conducted separately for each haz-
ardous constituent in each well.
(1)A parametric analysis of variance
(ANOVA) followed by multiple com-
parisons procedures to identify statis-
tically significant evidence of contami-
nation. The method must include esti-
mation and testing of the contrasts be-
tween each compliance well's mean
and the background mean levels for
each constituent.
(2) An analysis of variance (ANOVA)
based on ranks followed by multiple
comparisons procedures to identify
statistically significant evidence of
contamination. The method must in-
clude estimation and testing of the
contrasts between each compliance
well's median and the background
median levels for each constituent.
(3) A tolerance or prediction interval
procedure in which an interval for
each constituent is established from
-------
ฃfivirฐr,menta' Protection Agency
distribution of the background
t*1ฎ and the level of each constituent
d a'ch compliance well is compared to
>n e upper tolerance or prediction
the
limit
(4) A control chart approach that
gives
eflt-
control limits for each constitu-
(5) Another statistical test method
hat meets the performance standards
f ง 258.53(h). The owner or operator
must place a justification for this al-
ternative in the operating record and
notify the State Director of the use of
this alternative test. The justification
must demonstrate that the alternative
method meets the performance stand-
ards of ง 258.53(h).
(h) Any statistical method chosen
under ง 258.53(g) shall comply with
the following performance standards,
as appropriate:
(1) The statistical method used to
evaluate ground-water monitoring
data shall be appropriate for the dis-
tribution of chemical parameters or .
hazardous constituents. If the distri-
bution of the chemical parameters or
hazardous constituents is shown by
the owner or operator to be inappro-
priate for a normal theory test, then
the data should be transformed or a
distribution-free theory test should be
used. If the distributions for the con-
stituents differ, more than one statis-
tical method may be needed.
(2) If an individual well comparison
procedure is used to compare an indi-
vidual compliance well constituent
concentration with background con-
stituent concentrations or a ground-
water protection standard, the test
shall be done at a Type Terror level no
less than 0.01 for each testing period.
If a multiple comparisons procedure is
used, the Type I experiment wise error
rate for each testing period shall be no
less than 0.05; however, the Type I
error of no less than 0.01 for individ-
ual well comparisons must be main-
tained. This performance standard
does not apply to tolerance intervals,
prediction intervals, or control charts.
(3) If a control chart approach is
used to evaluate ground-water moni-
toring data, the specific type of con-
trol chart and its associated parameter
values shall be protective of human
health and the environment. The pa-
ง 258.53
sha11 be determined after
the number of samples in
the background data base t!f i
distribution, and the ranee of the coif
centration values for each constant
of concern.
(4) If a tolerance interval or a pre
dictional interval is used to evaluate
ground-water monitoring data, the
levels of confidence and. for tolerance
intervals, the percentage of the popu-
lation that the interval must contain,
shall be protective of human health
and the environment. These param-
eters shall be determined after consid-
ering the number of samples in the
background data base, the data distri-
bution, and the range of the concen-
tration values for each constituent of
concern. ^
(5) The statistical method shall ac-
count for data below the limit of de-
tection with one or more statistical
procedures that are protective of
human health and the environment.
Any practical quantitation limit (pql)
that is used in the statistical method
shall be the lowest concentration levei
that can be reliably achieved within
specified limits of precision and accu-
racy during routine laboratory operat-
ing conditions that are available to the
facility.
(6) If necessary, the statistical
method shall include procedures to
control or correct for seasonal and
spatial variability as well as temporal
correlation in the data.
(i) The owner or operator must de-
termine whether or not there is a sta-
tistically significant increase over
background values for each parameter
or constituent required in the particu-
lar ground-water monitoring program
that applies to the MSWLF unit, as
determined under งง 258.54(a) or
258.55(a) of this part.
(1) In determining whether a statis-
tically significant increase has oc-
curred. the owner or operator must
compare the ground-water quality of
each parameter or constituent at each
monitoring well designated pursuant
to ง 258.51(a)(2) to the background
value of that constituent, according to
the statistical procedures and perform-
ance standards specified under para-
-------
ง 258.54
(2) Within a reasonable period of
time after completing sampling and
analysis, the owner or operator must
determine whether there has been a
statistically significant increase over
background at each monitoring well.
ง 258.54 Detection monitoring program.
(a) Detection monitoring is required
at MSWLF units at all ground-water
monitoring wells defined under
งง 258.51 (a)(1) and (a)(2) of this part.
At a minimum, a detection monitoring
program must include the monitoring
for the constituents listed in appendix
I to this part.
(1) The Director of an approved
State may delete any of the appendix
I monitoring parameters for a
MSWLF unit if it can be shown that
the removed constituents are not rea-
sonably expected to be in or derived
from the waste contained in the unit.
(2) The Director of an approved
State may establish an alternative list
of inorganic indicator parameters for a
MSWLF unit, in lieu of some or all of
the heavy metals (constituents 1-15 in
appendix I to this part), if the alterna-
tive parameters provide a reliable indi-
cation of inorganic releases from the
MSWLF unit to the ground water. In
determining alternative parameters,
the Director shall consider the follow-
ing factors:
(i) The types, quantities, and concen-
trations of constituents in wastes man-
aged at the MSWLF unit;
(ii) The mobility, stability, and per-
sistence of waste constituents or their
reaction products in the unsaturated
zone beneath the MSWLF unit;
(iii) The detectability of indicator
parameters, waste constituents, and
reaction products in the ground water;
and
(iv) The concentration or values and
coefficients of variation of monitoring
parameters or constituents in the
groundwater background.
(b) The monitoring frequency for all
constituents listed in appendix I to
this part, or in the alternative list ap-
proved in accordance with paragraph
(a)(2) of this section, shall be at least
semiannual during the active life of
the facility (including closure) and the
post-closure period. A minimum of
four independent samples from each
40 CFR Ch. I (7-1-92 tAu.
well (background and downgra^,
must be collected and analyzed for
appendix I constituents, or the ait e
native list approved in accordn
with paragraph (a)(2) of this secu ^
during the first semiannual samnH'
event. At least one sample from e
well (background and downgradiem*1
must be collected and analyzed duri
subsequent semiannual sample6
events. The Director of an appr0v^
State may specify an appropriate ai
ternative frequency for repeated sam
pling and analysis for appendix I Cotl|
stituents, or the alternative list ap.
proved in accordance with paragraph
(a)(2) of this section, during the active
life (including closure) and the post-
closure care period. The alternative
frequency during the active life (in-
eluding closure) shall be no less than
annual. The alternative frequency
shall be based on consideration of the
following factors:
(1) Lithology of the aquifer and un-
saturated zone;
(2) Hydraulic conductivity of the aq-
uifer and unsaturated zone;
(3) Ground-water flow rates;
(4) Minimum distance between up-
gradient edge of the MSWLF unit and
downgradient monitoring well screen
(minimum distance of travel); and
(5) Resource value of the aquifer.
(c) If the owner or operator deter-
mines. pursuant to ง 258.53(g) of this
part, that there is a statistically signif-
icant increase over background for one
or more of the constituents listed in
appendix I to this part or in the alter-
native list approved in accordance
with paragraph (a)(2) of this section,
at any monitoring well at the bounda-
ry specified under ง 258.51(a)(2), the
owner or operator:
(1) Must, within 14 days of this find-
ing, place a notice in the operating
record indicating which constituents
have shown statistically significant
changes from background levels, and
notify the State director that this
notice was placed in the operating
record; and
(2) Must establish an assessment
monitoring program meeting the re-
quirements of ง 258.55 of this part
within 90 days except as provided for
in paragraph (c)(3) of this section.
-------
gvironmentol Protection Agency
The owner/operator may demon-
[e that a source other than a
^eWu1 unit causecI the contamina-
^ n or that the statistically signifi-
ti0nt increase resulted from error in
c^pling, analysis, statistical evalua-
n or natural variation in ground-
tlฐter quality. A report documenting
^is demonstration must be certified
a qualified ground-water scientist
r apPr0Veci by the Director of an ap-
proved State and be placed in the op-
erating record. If a successful demon-
stration is made and documented, the
owner or operator may continue detec-
tion monitoring as specified in this
section. If. after 90 days, a successful
demonstration is not made, the owner
or operator must initiate an assess-
ment monitoring program as required
in ง 258.55.
ง 258.55 Assessment monitoring program.
(a) Assessment monitoring is re-
quired whenever a statistically signifi-
cant increase over background has
been detected for one or more of the
constituents listed in the appendix I to
this part or in the alternative list ap-
proved in accordance with
ง 258.54(a)(2).
(b) Within 90 days of triggering an
assessment monitoring program, and
annually thereafter, the owner or op-
erator must sample and analyze the
ground water for all constituents iden-
tified in appendix II to this part. A
minimum of one sample from each
downgradient well must be collected
and analyzed during each sampling
event. For any constituent detected in
the downgradient wells as a result of
the complete appendix II analysis, a
minimum of four independent samples
from each well (background and down-
gradient) must be collected and ana-
lyzed to establish background for the
constituents. The Director of an ap-
proved State may specify an appropri-
ate subset of wells to be sampled and
analyzed for appendix II constituents
during assessment monitoring. The Di-
rector of an approved State may
delete any of the appendix II monitor-
ing parameters for a MSWLF unit if it
can be shown that the removed con-
stituents are not reasonably expected
to be in or derived from the waste con-
tained in the unit.
ง 258.55
(c) The Director of an approved
State may specify an appropriate al
ternate frequency for repeated sam-
pling and analysis for the full set of
appendix II constituents required by
ง 258.55(b) of this part, during the
active life (including closure) and post-
closure care of the unit considering
the following factors:
(1) Lithology of the aquifer and un-
saturated zone;
(2) Hydraulic conductivity of the aq-
uifer and unsaturated zone;
(3) Ground-water flow rates;
(4) Minimum distance between up-
gradient edge of the MSWLF unit and
downgradient monitoring well screen
(minimum distance of travel);
(5) Resource value of the aquifer;
and
(6) Nature (fate, ancf transport) of
any constituents detected in response
to this section.
(d) After obtaining the results from
the initial oi- subsequent sampling
events required in paragraph (b) of
this section, the owner or operator
must;
(1) Within 14 days, place a notice in
the operating record identifying the
appendix II constituents that have
been detected and notify the State Di-
rector that this notice has been placed
in the operating record;
(2) Within 90 days, and on at least a
semiannual basis thereafter, resample
all wells specified by ง 258.51(a), con-
duct analyses for all constituents in
appendix I to this part or in the alter-
native list approved in accordance
with ง.258.54(a)(2), and for those con-
stituents in appendix II to this part
that are detected in response to para-
graph (b) of this section, and record
their concentrations in the facility op-
erating record. At least one sample
from each well (background and down-
gradient) must be collected and ana-
lyzed during these sampling events.
The Director of an approved State
may specify an alternative monitoring
frequency during the active life (in-
cluding closure) and the post-closure
period for the constituents referred to
in this paragraph. The alternative fre-
quency for appendix I constituents, or
the alternative list approved in accord-
ance with ง 258.54(a)(2), during the
-------
ง 258.55
no less than annual. The alternative
frequency shall be based on consider-
ation of the factors specified in para-
graph (c) of this section:
(3) Establish background concentra-
tions for any constituents detected
pursuant to paragraph (b) or (d)(2) of
this section; and
(4) Establish ground-water protec-
tion standards for all constituents de-
tected pursuant to paragraph (b) or
(d) of this section. The ground-water
protection standards shall be estab-
lished in accordance with paragraphs
(h) or (i) of this section.
(e) If the concentrations of all ap-
pendix II constituents are shown to be
at or below background values, using
the statistical procedures in
ง 258.53(g), for two consecutive sam-
pling events, the owner or operator
must notify the State Director of this
finding and may return to detection
monitoring.
(f) If the concentrations of any ap-
pendix II constituents are above back-
ground values, but all concentrations
are below the ground-water protection
standard established under para-
graphs (h) or (i) of this section, using
the statistical procedures in
ง 258.53(g), the owner or operator
must continue assessment monitoring
in accordance with this section.
(g) If one or more appendix II con-
stituents are detected at statistically
significant levels above the ground-
water protection standard established
under paragraphs (h) or (i) of this sec-
tion in any sampling event, the owner
or operator must, within 14 days of
this finding, place a notice in the oper-
ating record identifying the appendix
II constituents that have exceeded the
ground-water protection standard and
notify the State Director and all ap-
propriate local government officials
that the notice has been placed in the
operating record. The owner or opera-
tor also:
(l)(i) Must characterize the nature
and extent of the release by installing
additional monitoring wells as neces-
sary;
(ii) Must install at least one addi-
tional monitoring well at the facility
boundary in the direction of contami-
nant migration and sample this well in
accordance with ง 258.55(d)(2);
40 CFR Ch. I (7-1-92 Ediซ0n)
(iii) Must notify all persons who 0w*
the land or reside on the land that df
rectly overlies any part of the plutj,
of contamination if contaminants hay6
migrated off-site if indicated by sanf
pling of wells in accordance with
ง 258.55 (g)(1); and
(iv) Must initiate an assessment 0f
corrective measures as required by
ง 255.56 of this part within 90 days; or
(2) May demonstrate that a source
other than a MSWLF unit caused the
contamination, or that the SSI in-
crease resulted from error in sampling;
analysis, statistical evaluation, or nat-
ural variation in ground-water quality.
A report documenting this demonstra-
tion must be certified by a qualified
ground-water scientist or approved by
the Director of an approved State and
placed in the operating record. If a
successful demonstration is made the
owner or operator must continue mon-
itoring in accordance with the assess-
ment monitoring program pursuant to
ง 258.55, and may return to detection
monitoring if the appendix II constitu-
ents are at or below background as
specified in ง 258.55(e). Until a success-
ful demonstration is made, the owner
or operator must comply with
ง 258.55(g) including initiating an as-
sessment of corrective measures.
(h) The owner or operator must es-
tablish a ground-water protection
standard for each appendix II constit-
uent detected in the ground-water.
The ground-water protection standard
shall be:
(1) For constituents for which a
maximum contaminant level (MCL)
has been promulgated under section
1412 of the Safe Drinking Water Act
(codified) under 40 CFR part 141, the
MCL for that constituent;
(2) For constituents for which MCLs
have not been promulgated, the back-
ground concentration for the constitu-
ent established from wells in accord-
ance with ง 258.51(a)(1); or
(3) For constituents for which the
background level is higher than the
MCL identified under paragraph
(h)(1) of this section or health based
levels identified under ง 258.55(i)(l),
the background concentration.
(i) The Director of an approved
State may establish an alternative
-------
gnVjronmen*al Protection Agency
onstituents for which MCLs have not
neen established. These ground-water
rotection standards shall be appropri-
Pte health based levels that satisfy the
following criteria:
(1) The level is derived in a manner
consistent with Agency guidelines for
assessing the health risks of environ-
mental pollutants (51 FR 33992, 34006,
34014. 34028, Sept. 24, 1986);
(2) The level is based on scientifical-
ly valid studies conducted in accord-
ance with the Toxic Substances Con-
trol Act Good Laboratory Practice
Standards (40 CFR part 792) or equiv-
alent:
(3) For carcinogens, the level repre-
sents a concentration associated with
an excess lifetime cancer risk level
(due to continuous lifetime exposure)
with the 1x10"4 to 1x10"6 range; and
(4) For systemic toxicants, the level
represents a concentration to which
the human population (including sen-
sitive subgroups) could be exposed to
on>a daily basis that is likely to be
without appreciable risk of deleterious
effects during a lifetime. For purposes
of this subpart, systemic toxicants in-
clude toxic chemicals that cause ef-
fects other than cancer or mutation.
(j) Ih establishing ground-water pro-
tection standards under paragraph (i)
of this section, the Director of an ap-
proved State may consider the follow-
ing:
(1) Multiple contaminants in the
ground water;
(2) Exposure threats to sensitive en-
vironmental receptors; and
(3) Other site-specific exposure or
potential exposure to ground water.
ง 258.56 Assessment of corrective meas-
ures.
(a) Within 90 days of finding that
any of the constituents listed in ap-
pendix II to this part have been de-
tected at a statistically significant
level exceeding the ground-water pro-
tection standards defined under
ง 258.55 (h) or (i) of this part, the
owner or operator must initiate an as-
sessment of corrective measures. Such
an assessment must be completed
within a reasonable period of time.
(b) The owner or operator must con-
tinue to monitor in accordance with
ง 258.57
SwiSun 5n25?505nit0rlng pro&ram 35
(c) The assessment shall include an
analysis of the effectiveness of poten-
tial corrective measures in meeting all
of. the requirements and objectives of
the remedy as described under
ง 258.57, addressing at least the follow-
ing:
(1) The performance, reliability, ease
of implementation, and potential im-
pacts of appropriate potential reme-
dies, including safety impacts, cross-
media impacts, and control of expo-
sure to any residual contamination;
(2) The time required to begin and
complete the remedy;
(3) The costs of remedy implementa-
tion; and
(4) The institutional-requirements
such as State or local permit require-
ments or other environmental or
public health requirements that may
substantially affect implementation of
the remedy(s).
. (d) The owner or operator must dis-
cuss the results of the corrective meas-
ures assessment, prior to the selection
of remedy, in a public meeting with in-
terested and affected parties.
ง 258.57 Selection of remedy.
(a) Based on the results of the cor-
rective measures assessment conduct-
ed under ง 258.56, the owner or opera-
tor must select a remedy that, at a
minimum, meets the standards listed
in paragraph (b) of this section. The
owner or operator must notify the
State Director, within 14 days of se-
lecting a remedy, a report describing
the selected remedy has been placed in
the operating record and how it meets
the standards in paragraph (b) of this
section.
(b) Remedies must:
(1) Be protective of human health
and the environment;
(2) Attain the ground-water protec-
tion standard as specified pursuant to
งง 258.55 (h) or (i);
(3) Control the source(s) of releases
so as to reduce or eliminate, to the
maximum extent practicable, further
releases of appendix II constituents
into the environment that may pose a
threat to human health or the envi-
-------
ง 258.57
(4) Comply with standards for man-
agement of wastes as specified in
ง 258.58(d).
(c) In selecting a remedy that meets
the standards of ง 258.57(b), the owner
or operator shall consider the follow-
ing evaluation factors:
(1) The long- and short-term effec-
tiveness and protectiveness of the po-
tential remedy(s), along with the
degree of certainty that the remedy
will prove successful based on consid-
eration of the following:
(1) Magnitude of reduction of exist-
ing risks;
(ii) Magnitude of residual risks in
terms of likelihood of further releases
due to waste remaining following im-
plementation of a remedy:
(iii) The type and degree of long-
term management required, including
monitoring, operation, and mainte-
nance:
(iv) Short-term risks that might be
posed to the community, workers, or
the environment during implementa-
tion of such a remedy, including po-
tential threats to human health and
the environment associated with exca-
vation, transportation, and redisposal
of containment;
(v) Time until full protection is
achieved;
(vi) Potential for exposure of
humans and environmental receptors
to remaining wastes, considering the
potential threat to human health and
the environment associated with exca-
vation, transportation, redisposal, or
containment;
(vii) Long-term reliability of the en-
gineering and institutional controls;
and
(viii) Potential need for replacement
of the remedy.
(2)'The effectiveness of the remedy
in controlling the source to reduce fur-
ther releases based on consideration of
the following factors:
(i) The extent to which containment
practices will reduce further releases;
(ii) The extent to which treatment
technologies may be used.
(3) The ease or difficulty of imple-
menting a potential remedy(s) based
on consideration of the following
types of factors:
(i) Degree of difficulty associated
with constructing the technology;
40 CFR Ch. I (7-1-92 Editj0||)
(ii) Expected operational reliabiiit
of the technologies: ^
(iii) Need to coordinate with anri
obtain necessary approvals and
mits from other agencies;
(iv) Availability of necessary equin
ment and specialists; and
(v) Available capacity and location
of needed treatment, storage, and dis-
posal services.
(4) Practicable capability of the
owner or operator, including a consid-
eration of the technical and economic
capability.
(5) The degree to which community
concerns are addressed by a potential
remedy(s).
(d) The owner or operator shall
specify as part of the selected remedy
a schedule(s) for initiating and com-
pleting remedial -activities. Such a
schedule must require the initiation of
remedial activities within a reasonable
period of time taking into consider-
ation the factors set forth in para-
graphs (d) (l)-(8) of this section. The
owner or operator must consider the
following factors in determining the
schedule of remedial activities:
(1) Extent and nature of contamina-
tion;
(2) Practical capabilities of remedial
technologies in achieving compliance
with ground-water protection stand-
ards established under ง 258.55 (g) or
(h) and other objectives of the
remedy;
(3) Availability of treatment or dis-
posal capacity for wastes managed
during implementation of the remedy;
(4) Desirability of utilizing technol-
ogies that are not currently available,
but which may offer significant advan-
tages over already available technol-
ogies in terms of effectiveness, reliabil-
ity, safety, or ability to achieve reme-
dial objectives;
(5) Potential risks to human health
and the environment from exposure to
contamination prior to completion of
the remedy;
(6) Resource value of the aquifer in-
cluding:
(i) Current and future uses;
(ii) Proximity and withdrawal rate
of users;
(iii) Ground-water quantity and
quality;
-------
gnvironmental Protection Agency
(jv) The potential damage to wild-
life, crops, vegetation, and physical
structures caused by exposure to waste
constituen t,
(v) The hydrogeologic characteristic
of the facility and surrounding land;
(Vi) Ground-water removal and
treatment costs; and
(vii) The cost and availability of al-
ternative water supplies.
(7) Practicable capability of the
owner or operator.
(8) Other relevant factors.
(e) The Director of an approved
State may determine that remediation
of a release of an appendix II constitu-
ent from a MSWLF unit is not neces-
sary if the owner or operator demon-
strates to the satisfaction of the Direc-
tor of the approved State that;
(1) The ground-water is additionally
contaminated by substances that have
originated from a source other than a
MSWLF unit and those substances are
present in concentrations such that
cleanup -of the release from the
MSWLF unit would provide no signifi-
cant reduction in risk to actual or po-
tential receptors; or
(2) The constituent(s) is present in
ground water that:
-------
ง 258.58
compliance with requirements of
ง 258.57(b) are not being achieved
through the remedy selected. Jn such
cases, the owner or operator must im-
plement other methods or techniques
that could practicably achieve compli-
ance with the requirements, unless the
owner or operator makes the determi-
nation under ง 258.58(c).
(c) If the owner or operator deter-
mines that compliance with require-
ments under ง 258.57(b) cannot be
practically achieved with any current-
ly available methods, the owner or op-
erator must:
(1) Obtain certification of a qualified
ground-water scientist or approval by
the Director of an approved State that
compliance with requirements under
ง 258.57(b) cannot be practically
achieved with any currently available
methods;
(2) Implement alternate measures to
control exposure of humans or the en-
vironment to residual contamination,
as necessary to protect human health
and the environment: and
(3) Implement alternate measures
for control of the sources of contami-
nation. or for removal or decontamina-
tion of equipment, units, devices, or
structures that are:
(i) Technically practicable: and
(ii) Consistent with the overall ob-
jective of the remedy.
(4) Notify the State Director within
14 days that a report justifying the al-
ternative measures prior to imple-
menting the alternative measures has
been placed in the operating record.
(d) All solid wastes that are managed
pursuant to a remedy required under
ง 258.57, or an interim measure re-
quired under ง 258.58(a)(3), shall be
managed in a manner:
(1) That is protective of human
health and the environment; and
(2) That complies with applicable
RCRA requirements.
(e) Remedies selected pursuant to
ง 258.57 shall be considered complete
when:
(1) The owner or operator complies
with the ground-water protection
standards established under
งง 258.55(h) or (i) at all points within
the plume of contamination that lie
beyond the ground-water monitoring
40 CFR Ch. I (7-1-92 Editj^
well system established Un
ง 258.51(a).
(2) Compliance with the grom.rt
water protection standards establish
under งง 258.55(h) or (i) has be**
achieved by demonstrating that co^
centrations of appendix II constitu
ents have not exceeded the grou^
water protection standard(s) for "
period of three consecutive years usw
the statistical procedures and perfon^
ance standards in ง 258.53(g) and (h)
The Director of an approved State
may specify an alternative length of
time during which the owner or opera-
tor must demonstrate that concentra-
tions of appendix II constituents have
not exceeded the ground-water protec-
tion standard(s) taking into consider-
ation:
(i) Extent and concentration of the
release(s);
(ii) Behavior characteristics of the
hazardous constituents in the ground-
water;
(iii) Accuracy of monitoring or mod-
eling techniques, including any season-
al, meteorological, or other environ-
mental variabilities that may affect
the accuracy; and
(iv) Characteristics of the ground-
water.
(3) All actions required to complete
the remedy have been satisfied.
(f) Upon completion of the remedy,
the owner or operator must notify the
State Director within 14 days that a
certification that the remedy has been
completed in compliance with the re-
quirements of ง 258.58(e) has been
placed in the operating record. The
certification must be signed by the
owner or operator and by a qualified
ground-water scientist or approved by
the Director of an approved State.
(g) When, upon completion of the
certification, the owner or operator de-
termines that the corrective action
remedy has been completed in accord-
ance with the requirements under
paragraph (e) of this section, the
owner or operator shall be released
from the requirements for financial
assurance for corrective action under
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^vjf0nmซntal Protection Agency
9258.59 [Reserved]
hpart FClosure And Post-Closure
Care
g 258.60 Closure criteria.
(a) Owners or operators of all
jyjsWLF units must install a final
cover system that is designed to mini-
mize infiltration and erosion. The
final cover system must be designed
constructed to:
(1) Have a permeability less than or
equal to the permeability of any
bottom liner system or natural sub-
soils present, or a permeability no
greater than 1x10"5 cm/sec, whichev-
er is less, and
(2) Minimize infiltration through
the closed MSWLF by the use of an
infiltration layer that contains a mini-
mum 18-inches of earthen material,
and
(3) Minimize erosion of the final
c(?ver by., the use of an erosion layer
that contains a minimum 6-inches of
earthen material that is capable of
sustaining native plant growth.
(b) The Director of an approved
State may approve an alternative final
cover design that includes:
(1) An infiltration layer that
achieves an equivalent reduction in in-
filtration as the infiltration layer spec-
ified in paragraphs (a)(1) and (a)(2) of
this section, and
(2) An erosion layer that provides
equivalent protection from wind and
water erosion as the erosion layer
specified in paragraph (a)(3) of this
section.
(c) The owner or operator must pre-
pare a written closure plan that de-
scribes the steps necessary to close all
MSWLF units at any point during
their active life in accordance with the
cover design requirements in
ง 258.60(a) or (b), as applicable. The
closure plan, at a minimum, must in-
clude the following information:
(1)A description of the final cover,
designed in accordance with
ง 258.60(a) and the methods and pro-
cedures to be used to Install the cover;
(2) An estimate of the largest area of
the MSWLF unit ever requiring a final
cover as required under ง 258.60(a) at
4 ^
ง258.60
ฐrthซ ln.
ever onX'over the
d
tivities necessary to satl'sfy^hTcW,^
pnfonn in A ORQ fin vlOSUre
active life of the land lU acStv ' h
(4.'. A completing an
criteria in ง 258.60.
(d) The owner or operator must
notify the State Director that a clo-
sure plan has been prepared and
placed in the operating record no later
than the effective date of this part, or
by the initial receipt of waste, which-
ever is later.
(e) Prior to beginning closure of
each MSWLF unit as specified in
ง 258.60(f), an owner or operator must
notify the State Director that a notice
of the intent to close the unit has been
placed in the operating record.
(f) The owner or operator must
begin closure activities of each
MSWLF unit ho later than 30 days
after the date on which the MSWLF
unit receives the known final receipt
of wastes or, if the MSWLF unit has
remaining capacity and there is a rea-
sonable likelihood that the MSWLF
unit will receive additional wastes, no
later than one year after the most
recent receipt of wastes. Extensions
beyond the one-year deadline for be-
ginning closure may be granted by the
Director of an approved State if the
owner or operator demonstrates that
the MSWLF unit has the capacity to
receive additional wastes and the
owner or operator has taken and will
continue to take all steps necessary to
prevent threats to human health and
the environmental from the unclosed
MSWLF unit.
(g) The owner or operator of all
MSWLF units must complete closure
activities of each MSWLF unit in ac-
cordance with the closure plan within
180 days following the beginning of
closure as specified in paragraph (f) of
this section. Extensions of the closure
period may be granted by the Director
of an approved State if the owner or
operator demonstrates that closure
will, of necessity, take longer than 180
days and he has taken and will contin-
ue to take all steps to prevent threats
to human health and the environment
from the unclosed MSWLF unit.
(h) Following closure of each
MSWLF unit, the owner or operator
-------
ง 258.61
certification, signed by an independent
registered professional engineer or ap-
proved by Director of an approved
State, verifying that closure has been
completed in accordance with the clo-
sure plan, has been placed in the oper-
ating record.
(1) (1) Following closure of all
MSWLF units, the owner or operator
must record a notation on the deed to
the landfill facility property, or some
other instrument that is normally ex-
amined during title search, and notify
the State Director that the notation
has been recorded and a copy has been
placed in the operating record.
(2) The notation on the deed must in
perpetuity notify any potential pur-
chaser of the property that:
(i) The land has been used as a land-
fill facility; and
(ii) Its use is restricted under
ง 258.61(c)(3).
(j) The owner or operator may re-
quest permission from the Director of
an approved State to remove the nota-
tion from the deed if all wastes are re-
moved from the facility.
[56 PR 51016, Oct. 9, 1991: 57 PR 28628,
June 26. 1992]
ง 258.61 Post-closure care requirements.
(a) Following closure of each
MSWLF unit, the owner or operator
must conduct post-closure care. Post-
closure care must be conducted for 30
years, except as provided under para-
graph (b) of this section, and consist
of at least the following:
(1) Maintaining the integrity and ef-
fectiveness of any final cover, includ-
ing making repairs to the cover as nec-
essary to correct the effects of settle-
ment, subsidence, erosion, or other
events, and preventing run-on and
run-off from eroding or otherwise
damaging the final cover;
(2) Maintaining and operating the
leachate collection system in accord-
ance with the requirements in ง 258.40,
if applicable. The Director of an ap-
proved State may allow the owner or
operator to stop managing leachate if
the owner or operator demonstrates
that leachate no longer poses a threat
to human health and the environ-
ment;
(3) Monitoring the ground water in
accordance with the requirements of
40 CFR Ch. I (7-1-93 ^
subpart E of this part and maintaซ
the ground-water monitoring Sv ~
if applicable; and
(4) Maintaining and operating
gas monitoring system in accord
with the requirements of ง 258.23 atlCe
(b) The length of the post-cl0s
care period may be: Ure
(1) Decreased by the Director of
approved State if the owner or oper*1
tor demonstrates that the reduced
period is sufficient to protect human
health and the environment and this
demonstration is approved by the Di-
rector of an approved State; or
(2) Increased by the Director of an
approved State if the Director of an
approved State determines that the
lengthened period is necessary to pro-
tect human health and the environ-
ment.
(c) The owner or operator of all
MSWLF units must prepare a written
post-closure plan that includes, at a
minimum, the following information:
(1)A description of the monitoring
and maintenance activities required in
ง 258.61(a) for each MSWLF unit, and
the frequency at which these activities
will be performed;
(2) Name, address, and telephone
number of the person or office to con-
tact about the facility during the post-
closure period; and
(3) A description of the planned uses
of the property during the post-clo-
sure period. Post-closure use of the
property shall not disturb the integri-
ty of the final cover, liner(s), or any
other components of the containment
system, or the function of the moni-
toring systems unless necessary to
comply with the requirements in this
Part 258. The Director of an approved
State may approve any other disturb-
ance if the owner or operator demon-
strates that disturbance of the final
cover, liner or other component of the
containment system, including any re-
moval of waste, will not increase the
potential threat to human health or
the environment.
(d) The owner or operator must
notify the State Director that a post-
closure plan has been prepared and
placed in the operating record no later
than the effective date of this part,
October 9, 1993, or by the initial re-
ceipt of waste, whichever is later.
-------
gpvlronmentai Protection Agency
(e) Following completion of the post-
closure care period for each MSWLF
onjt, the owner or operator must
notify the State Director that a certi-
fication, signed by an independent reg-
istered professional engineer or ap-
proved by the Director of an approved
State, verifying that post-closure care
has been completed in accordance
with the post-closure plan, has been
placed in the operating record.
[56 FR 51016. Oct. 9. 1991: 57 FR 28628,
June 26, 1992]
งง 258.62258.69 [ Reserved J
Subpart GFinancial Assurance
Criteria
Source: 56 FR 51029, Oct. 9. 1991, unless
otherwise noted.
Effective Date Note: At 56 FR 51029,
Oct. 9, 1991, Subpart G of Part 258 was
added, effective April 9. 1994.
ง 258.70 Applicability and effective date.
(a) The requirements of this section
apply to owners and operators of all
MSWLF units, except owners or oper-
ators who are State or Federal govern-
ment entities whose debts and liabil-
ities are the debts and liabilities of a
State or the United States.
(b) The requirements of this section
are effective April 9, 1994.
ง 258.71 Financial assurance for closure.
(a) The owner or operator must have
a detailed written estimate, in current
dollars, of the cost of hiring a third
party to close the largest area of all
MSWLF units ever requiring a final
cover as required under ง 258.60 at any
time during the active life in accord-
ance with the closure plan. The owner
or operator must notify the State Di-
rector that the estimate has been
placed in the operating record.
(1) The cost estimate must equal the
cost of closing the largest area of all
MSWLF unit ever requiring a final
cover at any time during the active life
when the extent and manner of its op-
eration would make closure the most
expensive, as indicated by its closure
plan (see 5 8.60(c)(2) of this part).
(2) During the active life of the
' . or rvnorator
ง 258.72
^ ^ C0St
cj43aLeT?LฐSurฐer c^festfmaSVnd
the amount of financial assurance pro-
vided under paragraph (b) of this sec
tion if changes to the closure plan or
MSWLF unit conditions increase the
maximum cost of closure at any time
during the remaining active life.
(4) The owner or operator may
reduce the closure cost estimate and
the amount of financial assurance pro-
vided under paragraph (b) of this sec-
tion if the cost estimate exceeds the
maximum cost of closure at any time
during the remaining life of the
MSWLF unit. The owner or operator
must notify the State Director that
the justification for^the reduction of
the closure, cost estimate and the
amount of financial assurance has
been placed in the operating record.
(b) The owner or operator of each
MSWLF unit must establish financial
assurance for closure of the MSWLF
unit in compliance with ง 258.74. The
owner or operator must provide con-
tinuous coverage for closure until re-
leased from financial assurance re-
quirements by demonstrating compli-
ance with ง 258.60(h) and (i).
[56 FR 51029. Oct. 9. 1991; 57 FR 28628,
June 26. 1992]
ง 258.72 Financial assurance for post-clo-
sure care.
(a) The owner or operator must have
a detailed written estimate, in current
dollars, of the cost of hiring a third
party to conduct post-closure care for
the MSWLF unit in compliance with
the post-closure plan developed under
ง 258.61 of this part. The post-closure
cost estimate used to demonstrate fi-
nancial assurance in paragraph (b) of
this section must account for the total
costs of conducting post-closure care,
including annual and periodic costs as
described in the post-closure plan over
the entire post-closure care period.
The owner or operator must notify the
State Director that the estimate has
been placed in the operating record.
(1) The cost estimate for post-clo-
sure care must be based on the most
expensive costs of post-closure care
-------
ง 258.73
(2) During the active life of the
MSWLF unit and during the post-clo-
sure care period, the owner or opera-
tor must annually adjust the post-clo-
sure cost estimate for inflation.
(3) The owner or operator must in-
crease the post-closure care cost esti-
mate and the amount of financial as-
surance provided under paragraph (b)
of this section if changes in the post-
closure plan or MSWLF unit condi-
tions increase the maximum costs of
post-closure care.
(4) The owner or operator may
reduce the post-closure cost estimate
and the amount of financial assurance
provided under paragraph (b) of this
section if the cost estimate exceeds
the maximum costs of post-closure
care remaining over the post-closure
care period. The owner or operator
must notify the State Director that
the justification for the reduction of
the post-closure cost estimate and the
amount of financial assurance has
been placed in the operating record.
(b) The owner or operator of each
MSWLF unit must establish, in a
manner in accordance with ง 258.74, fi-
nancial assurance for the costs of post-
closure care as required under ง 258.61
of this part. The owner or operator
must provide continuous coverage for
post-closure care until released from
financial assurance requirements for
post-closure care by demonstrating
compliance with ง 258.61(e).
ง 258.73 Financial assurance for correc-
tive action.
(a) An owner or operator of a
MSWLF unit required to undertake a
corrective action program under
ง 258.58 of this part must have a de-
tailed written estimate, in current dol-
lars, of the cost of hiring a third party
to perform the corrective action in ac-
cordance with the program required
under ง 258.58 of this part. The correc-
tive action cost estimate must account
for the total costs of corrective action
activities as described in the corrective
action plan for the entire corrective
action period. The owner or operator
must notify the State Director that
the estimate has been placed in the
operating record.
(1) The owner or operator must an-
nually adjust the estimate for infla-
40 CFR Ch. I (7-1-92 Edit5
tion until the corrective action h
gram is completed in accordance
ง 258.58(f) of this part. "lth
(2) The owner or operator must
crease the corrective action cost ป m
mate and the amount of financial
surance provided under paragraph
of this section if changes in the correc
tive action program or MSWLF u^u
conditions increase the maximum
costs of corrective action.
(3) The owner or operator may
reduce the amount of the corrective
action cost estimate and the amount
of financial assurance provided under
paragraph (b) of this section if the
cost estimate exceeds the maximum
remaining costs of corrective action.
The owner or operator must notify the
State Director, that the justification
for the reduction of the corrective
action cost estimate and the amount
of financial assurance has been placed
in the operating record.
(b) The owner or operator of each
MSWLF unit required to undertake a
corrective action program under
ง 258.58 of this part must establish, in
a manner in accordance with ง 258.74,
financial assurance for the most
recent corrective action program. The
owner or operator must provide con-
tinuous coverage for corrective action
until released from financial assurance
requirements for corrective action by
demonstrating compliance with
ง 258.58 (f) and (g).
ง 258.74 Allowable mechanisms.
The mechanisms used to demon-
strate financial assurance under this
section must ensure that the funds
necessary to meet the costs of closure,
post-closure care, and corrective action
for known releases will be available
whenever they are needed. Owners
and operators must choose from the
options specified in paragraphs (a)
through (j) of this section.
(a) Trust Fund, (1) An owner or op-
erator may satisfy the requirements of
this section by establishing a trust
fund which conforms to the require-
ments of this paragraph. The trustee
must be an entity which has the au-
thority to act as a trustee and whose
trust operations are regulated and ex-
amined by a Federal or State agency.
-------
gnvironmental Protection Agency
A copy of the trust agreement must be
placed in the facility's operating
record.
(2) Payments into the trust fund
jflust be made annually by the owner
or operator over the term of the initial
permit or over the remaining life of
the MSWliF unit, whichever Is short-
er. in the case of a trust fund for clo-
sure or post-closure care, or over one-
half of the estimated length of the
corrective action program in the case
of corrective action for known re-
leases. This period is referred to as the
pay-in period.
(3) For a trust fund used to demon-
strate financial assurance for closure
and post-closure care, the first pay-
ment into the fund must be at least
equal to the current cost estimate for
closure or post-closure care, except as
provided in paragraph (j) of this sec-
tion, divided by the number of years in
the pay-in period as defined in para-
graph (a)(2) of this section. The
ainount.of subsequent payments must
be determined by the following formu-
la:
CE-CV
Next Payment =
Y
where CE is the current cost estimate
for closure or post-closure care (updat-
ed for inflation or other changes), CV
is the current value of the trust fund,
and Y is the number of years remain-
ing in the pay-in period.
(4) For a trust fund used to demon-
strate financial assurance for correc-
tive action, the first payment into the
trust fund must be at least equal to
one-half of the current cost estimate
for corrective action, except as provid-
ed in paragraph (j) of this section, di-
vided by the number of years in the
corrective action pay-in period as de-
fined in paragraph (a)(2) of this sec-
tion. The amount of subsequent pay-
ments must be determined by the fol-
lowing formula:
RB-CV
Next Payment =
Y
whore RB is the most recent estimate
ง 258.74
corrective action (i.e., the total costs
that will be incurred during the
second half of the corrective action
period). CV is the current value of the
trust fund, and Y is the number of
years remaining on the pay-in period.
(5) The initial payment into the
trust fund must be made before the
initial receipt of waste or before the
effective date of this section (April 9,
1994), whichever is later, in the case of
closure and post-closure care, or no
later than 120 days after the correc-
tive action remedy has been selected
in accordance with the requirements
of ง 258.58.
(6) If the owner or operator estab-
lishes a trust fund after having used
one or more alternate mechanisms
specified in this section, the initial
payment into the trust fund must be
at least the amount that the fund
would contain if the trust fund were
established initially and annual pay-
ments made according to the specifica-
tions of this paragraph and ง 270.74(a)
of this section, as applicable.
(7) The owner or operator, or other
person authorized to conduct closure,
post-closure care, or corrective action
activities may request reimbursement
from the trustee for these expendi-
tures. Requests for reimbursement will
be granted by the trustee only if suffi-
cient funds are remaining in the trust
fund to cover the remaining costs of
closure, post-closure care, or corrective
action, and if justification and docu-
mentation of the cost is placed in the
operating record. The owner or opera-
tor must notify the State Director
that the documentation of the justifi-
cation for reimbursement has been
placed in the operating record and
that reimbursement has been received.
(8) The trust fund may be terminat-
ed by the owner or operator only if
the owner or operator substitutes al-
ternate financial assurance as speci-
fied in this section or if he is no longer
required to demonstrate financial re-
sponsibility in accordance with the re-
quirements of งง 258.71(b), 258.72(b),
or 258.73(b).
(b) Surety Bond Guaranteeing Pay-
ment or Performance. (1) An owner or
operator may demonstrate financial
assurance for closure or post-closure
-------
ง 258.74
formance surety bond which conforms
to the requirements of this paragraph.
An owner or operator may demon-
strate financial assurance for correc-
tive action by obtaining a performance
bond which conforms to the require-
ments of this paragraph. The bond
must be effective before the initial re-
ceipt of waste or before the effective
date of this section (April 9, 1994),
whichever is later, in the case of clo-
sure and post-closure care, or no later
than 120 days after the corrective
action remedy has been selected in ac-
cordance with the requirements of
ง 258.58. The owner or operator must
notify the State Director that a copy
of the bond has been placed in the op-
erating record. The surety company is-
suing the bond must, at a minimum,
be among those listed as acceptable
sureties on Federal bonds in Circular
570 of the U.S. Department of the
Treasury.
(2) The penal sum of the bond must
be in an amount at least equal to the
current closure, post-closure care or
corrective action cost estimate, which-
ever is applicable, except as provided
in ง 258.74(k).
(3) Under the terms of the bond, the
surety will become liable on the bond
obligation when the owner or operator
fails to perform as guaranteed by the
bond.
(4) The owner or operator must es-
tablish a standby trust fund. The
standby trust fund must meet the re-
quirements of ง 258.74(a) except the
requirements for initial payment and
subsequent annual payments specified
in ง 258.74 (a)(2), (3). (4) and (5).
(5) Payments made under the terms
of the bond will be deposited by the
surety directly into the standby trust
fund. Payments from the trust fund
must be approved by the trustee.
(6) Under the terms of the bond, the
surety may cancel the bond by sending
notice of cancellation by certified mail
to the owner and operator and to the
State Director 120 days in advance of
cancellation. If the surety cancels the
bond, the owner or operator must
obtain alternate financial assurance as
specified in this section.
(7) The owner or operator may
cancel the bond only if alternate fi-
nancial assurance is substituted as
40 CFR Ch. I (7-1-92 ^
specified in this section or if the
or operator is no longer requires r
demonstrate financial responsiblittl, fฐ
accordance with 5 258.71(b), 258
or 258.73(b).
(c) Letter of Credit (1) An owner o
operator may satisfy the requirement!
of this section by obtaining an irrevo
cable standby letter of credit which
conforms to the requirements of this
paragraph. The letter of credit must
be effective before the initial receipt
of waste or before the effective date of
this section (April 9, 1994), whichever
is later, in the case of closure and post-
closure care, or no later than 120 days
after the corrective action remedy has
been selected in accordance with the
requirements of ง 258.58. The owner or
operator must notify the State Direc-
tor that a copy of the letter of credit
has been placed in the operating
record. The issuing institution must be
an entity which has the authority to
issue letters of credit and whose letter-
of-credit operations are regulated and
examined by a Federal or State
agency.
(2) A letter from the owner or opera-
tor referring to the letter of credit by
number, issuing institution, and date,
and providing the following informa-
tion: Name, and address of the facility,
and the amount of funds assured,
must be included with the letter of
credit in the operating record.
(3) The letter of credit must be irrev-
ocable and issued for a period of at
least one year in an amount at least
equal to the current cost estimate for
closure, post-closure care or corrective
action, whichever is applicable, except
as provided in ง 258.74(a). The letter
of credit must provide that the expira-
tion date will be automatically ex-
tended for a period of at least one year
unless the issuing institution has can-
celled the letter of credit by sending
notice of cancellation by certified mail
to the owner and operator and to the
State Director 120 days in advance of
cancellation. If the letter of credit is
cancelled by the issuing institution,
the owner or operator must obtain al-
ternate financial assurance.
(4) The owner or operator may
cancel the letter of credit only if alter-
nate financial assurance is substituted
as specified in this section or if the
-------
Environmental Protection Agency
owner or operator Is released from the
requirements of this section in accord-
ance with ง 258.71(b), 258/72(b) or
258.73(b).
(d) Insurance. (1) An owner or oper-
ator may demonstrate financial assur-
ance for closure and post-closure care
by obtaining insurance which con-
forms to thfe requirements of this
paragraph. The insurance must be ef-
fective before the initial receipt of
waste or before the effective date of
this section (April 9, 1994), whichever
is later. At a minimum, the insurer
must be licensed to transact the busi-
ness of insurance, or eligible to provide
insurance as an excess or surplus lines
insurer, in one or more States. The
owner or operator must notify the
State Director that a copy of the in-
surance policy has been placed in the
operating record.
(2) The closure or post-closure care
insurance policy must guarantee that
funds will be available to close the
MSWLF unit whenever final closure
occurs -or to provide post-closure care
for the MSWLF unit whenever the
post-closure care period begins, which-
ever is applicable. The policy must
also guarantee that once closure or
post-closure care begins, the insurer
will be responsible for the paying out
of funds to the owner or operator or
other person authorized to conduct
closure or post-closure care, up to an
amount equal to the face amount of
the policy.
(3) The insurance policy must be
issued for a face amount at least equal
to the current cost estimate for clo-
sure or post-closure care, whichever is
applicable, except as provided in
ง 258.74(a). The term face amount
means the total amount the insurer is
obligated to pay under the policy.
Actual payments by the insurer will
not change the face amount, although
the insurer's future liability will be
lowered by the amount of the pay-
ments.
(4) An owner or operator, or any
other person authorized to conduct
closure or post-closure care, may re-
ceive reimbursements for closure or
post-closure expenditures, whichever
is applicable. Requests for reimburse-
ment will be granted by the Insurer
onlv if the remaining value of the
ง 258.74
policy is sufficient to cover the re-
maining costs of closure or post-clo-
sure care, and if justification and doc-
umentation of the cost is placed in the
operating record. The owner or opera-
tor must notify the State Director
that the documentation of the justifi-
cation for reimbursement has been
placed in the operating record and
that reimbursement has been received.
(5) Each policy must contain a provi-
sion allowing-assignment of the policy
to a successor owner or operator. Such
assignment may be conditional upon
consent of the insurer, provided that
such consent is not unreasonably re-
fused.
(6) The insurance policy must pro-
vide that the insurer .may not cancel,
terminate or fail to^renew the policy
except for failure to pay the premium.
The automatic renewal of the policy
must, at a minimum, provide the in-
sured with' the option of renewal at
the face amount of the expiring
policy. If there is a failure to pay the
premium, the insurer may cancel the
policy by sending notice of cancella-
tion by certified mail to the owner and
operator and to the State Director 120
days in advance of cancellation. If the
insurer cancels the policy, the owner
or operator must obtain alternate fi-
nancial assurance as specified in this
section.
(7) For insurance policies providing
coverage for post-closure care, com-
mencing on the date that liability to
make payments pursuant to the policy
accrues, the insurer will thereafter an-
nually increase the face amount of the
policy. Such increase must be equiva-
lent to the face amount of the policy,
less any payments made, multiplied by
an amount equivalent to 85 percent of
the most recent investment rate or of
the equivalent coupon-issue yield an-
nounced by the U.S. Treasury for 26-
week Treasury securities.
(8) The owner or operator may
cancel the insurance policy only if al-
ternate financial assurance is substi-
tuted as specified in this section or if
the owner or operator, is no longer re-
quired to demonstrate financial re-
sponsibility in accordance with the re-
quirements of ง 258.71(b). 258.72(b) or
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Pt. 258, App. I
(e) Corporate Financial Test [Re-
served]
(f) Local Government Financial
Test [Reserved]
(g) Corporate Guarantee. [Reserved]
(h) Local Government Guarantee.
[Reserved]
(i) State-Approved Mechanism. An
owner or operator may satisfy the re-
quirements of this section by obtain-
ing any other mechanism that meets
the criteria specified in ง 258.74(1),
and that is approved by the Director
of an approved State.
(j) State Assumption of Responsibil-
ity. If the State Director either as-
sumes legal responsibility for an
owner or operator's compliance with
the closure, post-closure care and/or
corrective action requirements of this
part, or assures that the funds will be
available from State sources to cover
the requirements, the owner or opera-
tor will be in compliance with the re-
quirements of this section. Any State
assumption of responsibility must
meet the criteria specified in
ง 25.8.74(1).
(k) Use of Multiple Financial Mecha-
nisms. An owner or operator may sat-
isfy the requirements of this section
by establishing more than one finan-
cial mechanism per facility. The mech-
anisms must be as specified in para-
graphs (a), (b), (c), (d), (e), (f), (g), (h),
(i), and (j) of this section, except that
it is the combination of mechanisms,
rather than the single mechanism,
which must provide financial assur-
ance for an amount at least equal to
the current cost estimate for closure,
post-closure care or corrective action,
whichever is applicable. The financial
test and a guarantee provided by a cor-
porate parent, sibling, or grandparent
may not be combined if the financial
statements of the two firms are con-
solidated.
(1) The language of the mechanisms
listed in paragraphs (a), (b), (c), (d),
(e), (f), (g). (h), (i), and (j) of this sec-
tion must ensure that the instruments
satisfy the following criteria:
(1) The financial assurance mecha-
nisms must ensure that the amount of
funds assured is sufficient to cover the
costs of closure, post-closure care, and
corrective action for known releases
when needed;
40 CFR Ch. I (7-1-92 Edition)
(2) The financial assurance mecha-
nisms must ensure that funds will be
available in a timely fashion when
needed;
(3) The financial assurance mecha-
nisms must be obtained by the owner
or operator by the effective date of
these requirements or prior to the ini-
tial receipt of solid waste, whichever is
later, in the case of closure and post-
closure care, and no later that 120
days after the corrective action
remedy has been selected in accord-
ance with the requirements of
ง 258.58. until the owner or operator is
released from the financial assurance
requirements under งง 258.71, 258.72
and 254.73.
(4) The financial assurance mecha-
nisms must be legally valid, binding,
and enforceable tinder State and Fed-
eral law.
Appendix I to Part 258Constitu-
ents for Detection Monitoring 1
Common name *
Inorganic Constituents:
(1) Antimony
(2) Arsenic
(3) Barium
(4) Beryllium
(5) Cadmium
(6) Chromium
(7) Cobalt
(8) Copper
(9) Lead
(10) Nickel
(It) Selenium
(12) Silver
(13) Thallium
(14) Vanadium
(15) Zinc
Organic Constituents:
(16) Acetone
(17) Acrylomtnle
(16) Benzene
(19) Bromochloromethane
(20) Bromodtchlorome thane
(21) Bromolorm; Tnbromomethane
(22) Carbon disulfide
(23) Carbon tetrachloride
(24) Chkxobenzene
(25) Chloroethane; Ethyl chloride
(26) Chloroform; Tnchloromethane
(27) Dibromochtofomethane: Chkxodibromo-
methane
(28) 1.2-Dibromo-3-chkxopropane; OBCP
(29) 1,2-Oibromoethane; Ethylene dtbromide:
eoe -
(30) o-DKhkyoberuene; 1.2-Dichloroben-
zene _
CAS RN >
(Total)
(Total)
(Tolal)
(Total)
(Total)
(Total)
(Total)
(Total)
(Total)
(Total)
(Tolal)
(Total)
(Total)
(Total)
(Total)
67-64-1
107-13-1
71-43-2
74-97-5
75-27-4
75-25-2
75-15-0
56-23-5
108-90-7
75-00-3
67-66-3
124-48-1
96-12-8
106-93-4
95-50-1
-------
gflvironmental Protection Agency
Continued
Pt. 258, App. II
Continued
Common name ฆ
pi) p-Dichlorobenzene; 1,4-Dichloroben-
zene
(32) trans-1.4-Oichloro-2-butene
(33) 1,1-Oichloroethane; Ethyfidene chloride..
(34) 1,2-Otchloroethane; Ethylene dichloride..
(35) t, 1 -Oichloroethylene; 1.1-Dichloroeth-
ene; Vinyl idene chloride
(36) os-1.2-Dictiloroethytene; ds-1,2-Dichlor-
oetftene
(37) trans-1.2-Dichloroethytone; trans-1,2-
Oichkxoethone
(38) 1.2-Dichloropropane; Propylene dtchlo-
riide - -
(39) ris-1,3-Dichloropropene
(40) trans-1.3-Oichloropropene
(41) Ethylbenzene
(42) 2-Hexanone; Methyl butyl ketone
(43) Methyl bromide: Bromomethane
(44) Methyl chloride; Chloromethane
(45) Methylene bromide; Dibromomethane
(46) Methylene chloride; Dtchloromethane...
(47) Methyl ethyl ketone; MEK; 2-Butanone....
(40) Methyl iodide; lodomethane
(49) 4-Methyl-2-pentanone; Methyl isobutyt
ketone
(50) Styrene
CAS RN ป
Common name *
106-46-7
110-57-6
75-34-3
107-06-2
75-35-4
156-59-2
156-60-5
78-87-5
10061-01-5
10061-02-6
100-41-4
591-78-6
74-83-9
74-87-3
74-95-3
75-09-2
78-93-3
74-88-4
108-10-1
100-42-5
(51) 1,t,1.2-Tetrachkxoethane
(52) 1.1,2,2-Tetrachloroethane
(53) Tetrachloroethyfene; Tetrachloroethene;
Perch loroethytene
(54) Toluene
(55) 1,1,1-Trichloroethane; Methytchlorolorm
(56) 1,1.2-Trichloroethane
(57) Trichloroethylene; Trichloroethene
(58) Trichlorofluoromethane; CFC-11
(59) 1,2,3-Trichkxopropane
(60) Vinyl acetate _
(61) Vinyl chlonde
(62) Xylenes -
CAS RN '
630-20-6
79-34-5
127-18-4
108-88-3
71-55-6
79-00-5
79-01-6
75-69-4
96-18-4
108-05-4
75-01-4
1330-20-7
1 This list contains 47 volatile organics (or which possible
analytical procedures provided in EPA Report SW-846 "Test
Methods for Evaluating Solid Waste," third edition, November
1986. as revised December 1987. includes Method 8260;
and 15 metals (or which SW-846 provides either Method
6010 or a method from the 7000 series of methods.
'Common names are those wktety^used in government
regulations, scienlific publications, and commerce; synonyms
exist for many chemicals.
1 Chemical Abstracts Service registry number. Where
"Total" is entered, all species in the ground water that
contain this element are included.
Appendix II to Part 258List of Hazardous Inorganic and Organic
Constituents 1
Common Name *
CAS RN s
Chemical abstracts service index name '
Sug-
gested
meth-
ods 1
POL (jig/
Acenaphthene
Acenaphthylene
Acetone
Acetonitrile; Methyl cyanide....
Acetophenone
2-Acetylaminofluorene; 2-AAF
Acrolein
Acrylonitrile
Aldnn
Ally) chlonde
4-Aminobiphenyl
Anthracene
Antimony
Arsenic
Banum
83-32-9
208-96-8
67-64-1
75-05-8
98-86-2
53-96-3
107-02-8
107-13-1
309-00-2
107-05-1
92-67-t
120-12-7
(Total)
(Total)
(Total)
Acenaphthylene, 1.2-dihydro-
Acenaphthylene
2-Propanone
Acetonitnle
Ethanone. 1-phenyl-
Acetamide, N-9H-(luoren-2-yl-
2-Propenal
2-Propene nitrite
1,4:5,8-Oime(hanonaphthalene.
1.2.3,4,10,10-hexachloro-1,4.4a,5,8,8a
hexahydro- (la.4a,4a/J,5a,8a.8a/})-
1-Propene. 3-chloro-
(1,1 '-BiphenyU-4-amine
Anthracene
Antimony
Arsenic
Barium
8100
200
8270
10
8100
200
8270
10
8260
100
8015
100
8270
10
8270
20
8030
5
8260
100
8030
5
8260
200
8080
0 05
8270
10
8010
5
8260
10
8270
20
8100
200
8270
10
6010
300
7040
2000
7041
30
6010
500
7060
10
7061
20
6010
20
7080
-------
Pt. 258, App. II
40 CFR Ch. I (7-1-92 Editj0(
n)
Continued
Common Name 1
Benzene.
BenzoC a ] anthracene: Benzanthracene
BenzoCblfluoranthene
Benzo[k]tluoranthene
Benzotghilperylene
Benzotalpyrene
Benzyl alcohol.
Beryllium
alpha-BHC
beta-BHC
delta-BHC
gamma-BHC; Lindane
Bis(2-chloroethoxy)methane.
Bis(2-cfitofoelhy0 ether Dichloroethyt
ether.
Bts-(2-chkx o-1 -methylethyt) ether. 2,2'-
Oichlorodiisopropyt ether. OOP. See
note 7
8is(2-ethylhexyl) phthalate
Bromochloromethane; Chlorobromometh-
ane.
Bromodichloromethane; Dibromochloro-
methane.
Bromoform, Tribromomethane..
4-Bromophenyt phenyl ether....
Butyl benzyl phthalate; Benzyl butyl
phthalate.
Cadmium
Carbon disulfide
Carbon tetrachloride.
Chlordane.
p-Chloroaniline..
Chlorobenzene.
Chlorobenzilate..
p-Chk)ro-m-cresol.
phenol
Chloroethane; Ethyl chloride
4-Chloro-3-methyl-
CAS RN *
71-43-2
56-55-3
205-99-2
207-08-9
191-24-2
50-32-8
100-51-6
(Total)
319-84-6
319-85-7
319-86-8
58-89-9
111-91-1
111-44-4
108-60-1
117-81-7
74-97-5
75-27-4
75-25-2
101-55-3
85-68-7
(Total)
75-15-0
56-23-5
See Note 8
106-47-8
108-90-7
510-15-6
59-50-7
75-00-3
Chemical abstracts service index name
Benzene
BenzCalanthracene
Benzt e ] acephenanthrylene
BenzoEklfluoranthene
Benzotghi Jperylene
Benzo[a]pyrene
Benzenemethanol
Beryllium
Cyclohexane. 1,2,3,4.5,6-hexachloro-.
(1a.2a.3/3.4a.50.60)-.
Cyclohexane. 1,2.3,4.5.6-hexachloro-.
(1a.20,3a.40,5a.60)-.
Cyclohexane. 1.2.3,4,5.6-hexachloro-.
(I a,2a,3a.4p,5a.6(3)-.
Cyclohexane, 1,2,3.4,5,6-hexachloro-.
(1a.2a.3/3,4a;'5a.6/3)-.
Ethane. 1.1 '-[methy1enebis(oxy)]bis[2-
chkxo-.
Ethane. 1.1'-oxybซs[2-ehlofo-
Propane. 2.2'-oxybis[1-chloro-.
1,2-Benzenedicarboxylic acid, bis(2-ethyl-
hexyl) ester.
Methane, bromochloro-
Methane, bromodichloro-.
Methane, tnbromo-..
Benzene. 1-bromo-4-phenoxy-
1.2-Benzenedicarboxylic acid, butyl phen-
ylmelhyl ester.
Cadmium
Cartoon disulfide
Methane, tetrachloro-.
4.7-Methano-1 H-indene, 1.2.4,5.6,7.8,8-
oc1achloro-2.3.3a.4.7,7a-hexahydro-.
Benzenamine. 4-chloro-
Benzene, chloro-
Benzeneacetic acid, 4-chlor
-------
Environmental Protection Agency
Pt. 258, App. II
Continued
Common Name *
Chloroform; Tnchloromethane..
2-Chloronaphthalene
2-Chlorophenol
4-Chlorophenyt phenyl ether..
Chloroprene
Chromium
Ctvysene.
Cobalt
Copper.
m-Cresol; 3-methylphenol
o-Cresol; 2-methytphenol
p-Creso); 4-methy(phenol
Cyanide
2.4-0; 2,4-Dichlorophenoicyacetic acid..
4.4'-O00 _ _....
4.4ป-ODE
4.4'-OOT
Oiallate
ObenzCa.hJanthracene
Dibenzofuran
Dibromochloromethane; Chlorodibromo-
methane.
1.2-Dibromo-3-chloropropane: DHCP
1,2-Dibromoethane; Ethylene dribromide:
GOB.
Oi-n-butyl phthalate
o-Dichlorobenzene; 1.2-Dichlorobenzene..
m-Dichlorobenzene: 1,3-Dichlorobenzene.
p-Oichlorobenzene; 1.4-Dichkxobenzene...
CAS RN 1
Chemical abstracts service index name *
Sug-
gested
meth-
ods 1
POL (ug/
UT
67-66-3
Methane, tnchloro-
8010
0.5
8021
0.2
8260
5
91-58-7
Naphthalene, 2-chkxo-
8120
10
8270
10
95-57-6
Phenol. 2-chkxo-
8040
5
8270
10
7005-72-3
Benzene. 1-chloro-4-phenoxy-
8110
40
8270
10
126-99-8
1.3-Butadiene. 2-chkxo-
8010
50
8260
20
(Total)
Chromium
6010
70
7190
500
7191
10
218-01-9
Chrysene -
8100
200
8270
10
(Total)
Cobalt
6010
70
7200
500
7201
10
(Total)
Copper
6010
60
7210
200
7211
10
108-39-4
Phenol. 3-methyt-
8270
10
95-48-7
Phenol. 2-methyl-..._
8270
10
106-44-5
Phenol. 4-methyl-
8270
10
57-12-5
Cyanide
9010
200
94-75-7
Acetic acid, (2.4-dichlorophenoxy)-._
8150
10
72-54-8
Benzene 1.l'-(2,2-
8080
0.1
dtcWoroethyfidene)bts(4-chtoro-.
8270
10
72-55-9
Benzene. 1.1'-
8080
0.05
(dichloroethyenylidene)bisC4-chloro-.
8270
10
50-29-3
Benzene. 1.1' -{2.2.2-
8080
0.1
tnchloroethylidene)bis[4-chloro-.
8270
10
2303-16-4
Carbamothioic acid, bis(1-methylethy1)-.S-
8270
10
(2.3-dichloro-2-propeny1) ester.
53-70-3
Dibenz[a,h)anthracerve
8100
200
8270
10
132-64-9
Dibenzofuran
8270
10
124-48-1
Methane, dibromochloro-
8010
1
8021
0.3
8260
5
96-12-8
Propane. l.2-dibrome-3-chloro-
8011
0.1
8021
30
8260
25
106-93-4
Ethane. 1.2-dibromo-
8011
0.1
8021
10
8260
5
84-74-2
1.2-Benzenedicarboxylic acid. dibutyl
8060
5
ester.
8270
10
95-50-1
Benzene. 1,2-d'ichkxo-
8010
2
8020
5
8021
0.5
8120
10
6260
5
6270
10
541-73-1
Benzene. 1,3-Oichloro-
8010
5
8020
5
8021
0.2
8120
10
8260
5
8270
10
106-46-7
Benzene, 1.4-dichloro-
8010
2
8020
5
8021
0 1
8120
15
8260
5
8270
-------
Pf. 258, App. II
40 CFR Ch. I (7-1-92 Editj0n)
Continued
Common Name *
3,3 -Dtchlorobenridine..
trans-1,4-Dtchlofo-2-bi/tene
Dichlorodifluoromethane; CFC 12;
1,1 -Dtchlofoethane; Ethytdidene chloride ...
1.2-Oichloroethane: Ethylene dichloride
1,1-Dtchloroethyiene; 1,1 -Oictikxoethene;
Vinyl idene chloride.
cis-1,2-Dichloroethylene; cปs-1,2-Dichlor-
oethene.
trans-1.2-Oichkxoethytene trans-1,2-Dich-
loroethene.
2,4-OtchlOfopheno).
2.6-Dtchlorophenol
1,2-Oichloropropane; Propylene dichlonde
1.3-Dichloropropane; Trimethytene dichlo-
nde.
2,2-DicNoropropane; Isopropylidene chlo-
ride'.'
t, 1 -Dtchloropropene
as-1.3-DปchlofopfOpene._
trans-1.3-Dtchkxopropene
Oieldnn
Diethyl phthalate
O.O-Oethyt 0-2-pyrazinyl phosphoroth-
loate; Thiemann.
Omethoate
p-(Dimethylamino)azobenzene
7.12-Dimethylbenz[a]anthracene
3.31 -Dimethyl benzidine
2.4-Dimethylphenol; m-Xylenol
Dimethyl phthalate
m-Dtnitrobenzeoe
4,6-Onitro-o-cresol 4,6-Dirvitro-2-methyl-
pheno).
2,4-Omitrophenol:
2,4-Dinitrotoluene
2.6-Dinitrotoluene
Dinoseb, DNBP; 2-sec-Butyl-4,6-dinitro-
phenol.
Oi-n-octyl phthalate
Ophenytamine
CAS RN 5
91-94-1
110-57-6
75-71-6
75-34-3
107-06-2
75-35-4
156-59-2
156-60-5
120-83-2
87-65-0
78-87-5
142-28-9
594-20-7
563-58-6
10061-01-5
10061-02-6
60-57-1
64-66-2
297-97-2
60-51-5
60-11-7
57-97-6
119-93-7
105-67-9
131-11-3
99-65-0
534-52-1
51-28-5
121-14-2
606-20-2
88-85-7
117-84-0
122-39-4
Chemical abstracts service index name *
[1.1'-BiphenylM^'-diamine, 3.3'-dtch-
Ioro-.
2-Butene. 1,4-dichloro-, (E)-
Methane, dichkxodifluoro-
Ethane. 1,1-dtchkxo-.
Ethane, 1,1 -dichloro-..
Ethene, 1.1-dichloro-..
Ethene, 1,2-dichloro-. (Z)-
Etherve, 1.2-dichloro-. (ฃ)-
Phenol, 2.4-dichkxo-..
Phenol. 2,6-dichloro-....
Propane. 1,2-dichkxo-.
Propane, 1.3-dichloro-
Propane, 2,2-dichloro-
1-Propene, 1.1-dichloro-
1-Propane, 1,3-dichloro-. (Z)-.
1-Propene, 1,3-dicWoro-. (ฃ)-.
2,7:3.6-Dimetharปonaphtht2.3-b]oxirene.
3.4,5.6.9,9-hexa, chloro-
1 a,2,2a.3.6,6a.7,7a-octahydro-,
(1 aa,2/3.2aa.3^.6/3.6aa. 7j3,7aa)-.
1,2-Benzenedfcarboxylic acid, diethyl
ester.
Phosphorothioic acid, 0.0-diethyl 0-pyra-
zinyl ester.
Phosphorochthioic acid. 0.0-dimethyl S-C2-
(methytam
-------
0nvironmental Protection Agency
Continued
Pt. 258, App. II
Common Name *
Qtsulloton
Endosulfan I
Endosulfan II
Endosulfan sulfate
Endrin
Endrin aldehyde
Ethylbenzene
-Ethyl methacrylate
Ethyl methanesulfonate
Famphur !
Fluoranthene
Fluorene
Heptachlor
Heptachlof epoxide
Hexachlorobenzene
HexacMorobotadiene
Hexachlorocydopentadiene
Hexachloroethane
Hexachloropropene
2-Hexanone; Methyl butyl ketone
lndeno(l.2,3-cd)pyrene
Isobutyt alcohol
Isodrm
Isophorone
Isosafrole
Kepone
CAS RIM 1
298-04-4
959-98-8
33213-65-9
1031-07-8
72-20-8
7421-93-4
100-41-
97-63-2
62-50-0
52-85-7
206-44-0
86-73-7
76-44-6
1024-57-3
118-74-1
87-68-3
77-47-4
67-72-1
1888-71-7
591-78-6
193-39-5
78-83-1
465-73-6
78-59-1
120-58-1
143-50-0
Phosphorodithiotc acid, 0.0-diethyt S-C2-
(ethy1thio)elhy<] ester.
6,9-Methano-2,4.3-benzodtoxathiepin,
6.7,8,9,10,10-hexa- chloro-
1,5.5a.6.9,9a-hexahydro-, 3-oxide,
6.9-Methano-2,4.3-benzodioxathtepin,
6.7,8,9.10,10-hexa- chtoro-
1.5,5a.6,9,9a-hexahydfo-. 3-oxide.
(3a.5aa.60.9/J.9aa)-.
6,9-Methano-2.4,3-benzodioxathieptn,
6.7,8.9.10,10-hexa- chkxo-
1,5.5a.6.9,9a-hexahydro-.3-3-dioxide.
2.7:3,6-Dimethanonaphm[2.3-b]oxirene,
3,4.5,6,9,9-hexachloro-
1a.2,2a.3.6,6a,7.7a-octahydro-. (laa.
20.2a/3,3a.6a,6a/J.70.7aa)-.
1,2.4-Methenocyck)penta[cd]pentalene^-
carboxaldehyde, 2,2a,3.3,4.7-hexachlor-
odecahydro-, . (1a,2/?,2aฃ.4/3
,4a/5.5/3.6aฃ,6b/3.7R"}-.
Benzene, ethyl-
2-Propenoic acid. 2-methyt-. ethyl ester.
Sug-
gested
meth-
ods ป
Methanesulfonic acid, ethyl ester
Phosphorothiotc aod.
[ (de, 1,4,5,6.7.8.8-he[>-
tachloro-3a.4,7,7a-tetrahydro-.
2,5-Wethano-2H-indervo[ 1,2-b ]oxirene,
2,3,4,5.6.7,7-heptachkxo-
la.lb.5.5a.6,6a-hexahydro-. (laa. 1b/3,
2a. 5a, 5a/J, 6/3, 6aa).
Benzene, hexachloro-
1,3-Butadiene, 1,1.2,3,4,4-hexachloro-
1,3-Cyclopentadiene, 1.2,3,4.S.S-hexach-
loro-.
Ethane, hexachloro-
1-Propene, 1,1,2.3,3,3-hexachloro-
2-Hexa none
lndeno<1.2,3-ซJ)pyrene
1-Propanol, 2-methyt-
1.4.5.8-
Oimethanonaphthalene. 1.2.3,4.10.10-
hexachtoro-1,4,4a.S,8,8a hexahydro-
(1a.4a.4a/}.5/3.80.8a0)-.
2-Cyck>hexen-1-ooe. 3.5,5-tnmethyt-
1.3-Benzodtoxole, 5-<1-propeny1)-
1.3,4-MetherK>-2H-cyc
-------
Pt. 258, App. II
40 CFR Ch. I (7-1-92 Editj0|
n)
Continued
Common Name '
CAS RN 1
Chemical abstracts service index name ซ
Sug-
gested
meth-
ods '
PQu
Lead
Mercury
Methacrylomtrile
Methapyrilene
Methoxychlor
Methyl bromide; Bromomethane
Methyl chloride; Chkxome thane
3-Methyfcholanthren e
Methyl ethyt ketone; MEK; 2-Butanone
Methyl iodide; lodomethane
Methyl methacrytate
Methyl methanesulfonate
2-Methylnaphthalene
Methyl parathion; Parathion methyl
4-Methy1-2-pentanone; Methyl isobutyl
ketone.
Methylene bromide; .Oibromome thane
Methylene chloride; Dichtorome thane.
Naphthalene..
1,4-Naphthoquinone..
1-Naphthylamin e
2-Naphthylamin e
Nickel
o-Nitroamline; 2-Nitroaniline..
m-Nitroaniline; 3-Nitroanile...
p-Nitroaniline; 4-Nitroaniline.,
Nitrobenzene
o-Nitrophenol; 2-Nitrophenol..
p-Nitrophenol; 4-Nitrophenol..
N-Nitrosodi-n-butylamirปe
N-Nitrosodiethylamine
N-Nitrosodimethylamine
N-Nitrosodiphenylamine
N-Nitrosodipropylamine; N-Nitroso-N-di-
propylamme; Di-n-propylnitrosamine.
N-Nitrosomethylethalamme
N-Nitrosopiperidine...-
N-Nitrosopyrrolidine
5-Nitro-o-loluidine
Parathion
Pentachlorobenzene
Pentachloronitrobenzene..
(Total)
(Total)
126-98-7
91-80-5
72-43-5
74-83-9
74-87-3
56-49-5
78-93-3
74-88-4
80-62-6
66-27-3
91-57-6
298-00-0
108-10-1
74-95-3
75-09-2
91-20-3
130-15-4
134-32-7
91-59-8
(Total)
88-74-4
99-09-2
100-01-6
98-95-3
88-75-5
100-02-7
924-16-3
55-18-5
62-75-9
86-30-6
621-64-7
10595-95-6
100-75-4
930-55-2
99-55-8
56-38-2
608-93-5
82-68-8
Lead
Mercury
2-Propenerutnle. 2-methyl-
1,2-Ethanediamine, N.N-dimethy1-N'-2
pyndinyl-N 1 /2-thienylmethyl)-.
Benzene, 1.1
(2,2,2,trichloroethylidene)bis[4-methoxy
Methane, bromo-
Methane, chkxo-
Benzljlaceanthrylene, 1,2-dihydro-3
methyl-.
2-Butanone
Methane, iodo-
2-Propenoic acid, 2-methyl-. methyl ester
Methanesulfonic acid, methyl ester
Naphthalene, 2-methyl-
Phosphorothioic acid. 0,0-dimethyt
2-Pentanone. 4-methyl-
Methane. dibromo-
Methane, dtchloro-.
Naphthalene..
1,4-Naphthalenedione..
1 -Naphthalenamine
2-Naphthalenamine
Nickel
Benzenamine. 2-nitro-..
Benzenamine. 3-nitro-..
Benzenamine, 4-rwtro...
Benzene, nitro-
Phenol, 2-nitro-.
Phenol. 4-nitro-.
1 -Butanamine. N-butyl-N-nitroso-
Ethanamine. N-ethyl-N-nitroso-
Methanamirve. N-methyl-N-nitroso-..
Benzenamine. N-nitroso-N-phenyl-..
1 -Propanamine. N-mtroso-N-propyl-
Ethanamine, N-methyl-N-rutroso-
Piperidine. 1 -mtroso-
Pyrrolidine, 1-mtroso-
Benzenamine, 2-methyt-5-mtro-
Phosphorothioic acid. 0.0-diethyl 0-(4-ni-
trophenyl) ester.
Benzene, pentachkxo-
Benzene, pentachkxorotro-
6010
7420
7421
7470
8015
8260
8270
8080
8270
8010
8021
8010
8021
8270
8015
8260
8010
8260
8015
8260
8270
8270
8140
8141
8270
8015
8260
8010
8021
6260
8010
8021
8260
8021
8100
8260
8270
8270
8270
8270
6010
7520
8270
8270
8270
8090
8270
8040
8270
8040
8270
8270
8270
8070
8070
8070
8270
8270
8270
8270
8141
8270
8270
8270
-------
gitvironmental Protection Agency
Continued
Pt. 258, App. II
Common Name *
pentachlorophenol
Phenacetin
phenanlhrene
Phenol -
P^>henylenediamine
Phorate
polychlorinated biphenyls: PC8s: Arodors
Pronamide
proptonitrile; Ethyl cyanide
Pyrene
Safrole
Selenium
Silver
SHvex; 2.4.5-TP
Styrene
Sulfide
2,4,5-T; 2.4,5-TricMofophenoxyacetic acid
1.2.4.5-Tetrachlorobenzene
1.1.1.2-Tetrachloroethane
1.1,2.2-Tetrachloroethane
T etrachlor oelhylene; T etrachloroethene;
Perchloroethylene.
2.3,4,6-Tetrachlorophenol
Thallium
Tin
Toluene
o-Toluidine
Toxaphene
1.2.4-Trichlorobenzene
1.1,1 -Tnchloroethane; Methylchlorof orm....
1, t ,2-Tnchloroethane
Trichlofoethylene: Trichlofoethene
Trichlorofluoromelhane. CFC-11
2,4.5-Tfichlorophenol ...
CAS RN "
87-86-5
62-44-2
85-01-8
108-95-2
106-50-3
298-02-2
See Note 9
23950-58-5
107-12-0
129-00-0
94-59-7
(Total)
(Total)
93-72-1
100-42-5
18496-25-8
93-75-5
95-94-3
630-20-6
79-34-5
127-18-4
58-90-2
(Total)
(Total)
108-88-3
95-53-4
See Note 10
120-82-t
71-55-6
79-00-5
79-01-6
Chemical absuacts iannca ^ ^ ,
Sug-
gested
mettv-
ods k
Phenol, pentachlofo-..
Acetamida, N-(4-ethoxyphenl).
Phenanthrene
Phenol
1,4-Benzenedcamine
Phosphorodithioic acid. 0.0-diethyl S-
[(ethytthio)methyU ester.
I.l'-Biphenyl. chloro derivatives..
Benzamide, 3.5-dtchkxo-N-O.l.dimeihyl-
2-prapyny))-.
Propanerwtrile
6040
8270
8270
8100
8270
B040
8270
PCH. (pg/
Pyrene
1.3-Benzodioxole, 5-(2-propenyl)-.
Selenium
Silver.
Propanoic actd. 2-(2.4.5-trichlorophen-
oxy)-.
Benzene, ethenyt-
Sulfide
Acetic acid. (2.4,S-trichlofopheno>cy)-
Benzene. 1.2,4.5-tetrachloro-
Ethane. 1,1.1.2-tetrachloro-
Ethane, 1,1,2,2-telrachloro-...
Ethene, tetrachloro-.
Phenol. 2,3.4.6-tetrachloro-..
Thallium
Tin
Benzene, melhyt-
Benzenamine, 2-methyl- .
Toxaphene
Benzene, 1,2,4-trichlofO-.
Ethane. 1.1,1-lrichlOfO-
E thane. 1.1,2-tnchloro-
Ethene. trichloro-
75-69-4 Methane, Irichlorotluoro-
95-95-4 Phenol. 2.4.5-tnchloro- ...
5
50
20
200
10
1
10
8140
2
8141
0.5
8270
10
8080
SO
8270
200
8270
10
8015
60
8260
150
8100
200
8270
10
8270
10
6010
750
7740
20
7741
20
6010
70
7760
100
7761
10
8150
2
B0 20
1
8021
0.1
8260
10
9030
4000
8150
2
8270
10
8010
5
8021
0.05
8260
5
8010
0 5
8021
0 1
8260
5
8010
0 5
8021
0.5
8260
5
8270
10
6010
400
7840
1000
7841
10
6010
40
8020
2
8021
0 1
8260
5
8270
10
8080
2
8021
0 3
8120
0 5
8260
10
8270
10
8010
0 3
8021
03
8260
S
8010
0 2
8260
5
8010
1
8021
02
8260
5
8010
10
8021
0 3
8260
5
8270
-------
Pt. 258, App. II
40 CFR Ch. I (7-1-92 Edition)
Continued
Common Name *
CAS AN'
Chemical abstracts service index name 4
Sug-
gested
meth-
ods *
2.4,6-Tnchlocopheoo)....
1,2,3-T richloropropane..
0,0.0-Triethyt phosphorothioate.
sym-T nnitrobenzene
Vanadium
Vinyl acetate
Vinyl chloride; Chloroethene..
88-06-2
96-18-4
126-68-1
99-35-4
(Total)
t08-05-4
75-01-4
Xylene (total)..
Zinc.
See Note 11
(Total)
Phenol, 2.4,6-trichkxo-
Propane, 1,2.3-tnchloro-
Phospborothi oc acid. 0,0.0-tnethylester
Benzene, 1.3.5-tnmtro-
Vanadium
Acetic acid, ethenyt ester
Etbene, chloro-
Benzene, dimethyl-
Zinc
8040
5
8270
10
8010
10
8021
5
8260
15
8270
10
8270
10
6010
80
7910
2000
7911
40
8260
50
8010
2
8021
0.4
8260
10
8020
5
6021
0.2
8260
5
6010
20
7950
50
7951
0.5
Notes
1 The regulatory requirements pertain only to the list of substances; the right hand columns (Methods and POL) are given tor
informational purposes only. See also footnotes 5 and 6.
1 Common names are those widely used in government regulations, scientific publications, and commerce; synonyms exist
for many chemicals.
' Chemical Abstracts Service registry number. Where "Total" is entered, all species in the ground water that contain this
element are included.
4 CAS index are those used in the 9th Collective Index.
Suggested Methods refer to analytical procedure numbers used in EPA Report SW-846 "Tesl Methods for Evaluating Solid
Waste . third edition, November 1986, as revised, December 1987. Analytical details can be found in SW-846 and in
documentation on file at the agency. CAUTION: The methods listed are representative SW-846 procedures and may not
always be the most suitable metnod(s) for monitoring an analyte under the regulations.
Practical Quantitation Limits (PQLs) are the lowest concentrations of anaiytes in ground waters that can be reaiiabty
determined within specified limits of precision and accuracy by the indicated methods under routine laboratory operating
conditions. The POLs listed are generally stated to one significant figure. PQLs are based on 5 mL samples for volatile
organics and 1 L samples for seriwolatile organics. CAUTION; The POL values in many cases are based only on a general
estimate for the method and not on a determination for individual compounds; PQLs are not a part of the regulation.
1 This substance is often called Bis(2-chloroisopropyf) ether, the name Chemical Abstracts Service applies to its
noncommercial isomer, Propane. 2.2"-oxybis(2-chloro- (CAS RN 39638-32-9).
Chlordane: This entry includes alpha-chlordane (CAS RN S103-7I-9), beta-chlordane (CAS RN 5103-74-2). gamma-
chlordane (CAS RN 5566-34-7), and constituents of chlordane (CAS RN 57-74-9 and CAS RN 12789-03-6). PQl shown is
for technical chlordane PQLs of specific isomers are about 20 hq/L by method 8270.
Polychlonnated biphenyls (CAS RN 1336-36-3); this category contains congener chemicals, including constituents of
Aroclor 1016 (CAS RN 12674-11-2). Aroclor 1221 (CAS RN 11104-28-2). Aroclor 1232 (CAS RN 11141-16-5), Aroclor 1242
(CAS RN 53469-21-9), Aroclor 1248 (CAS RN 12672-29-6), Aroclor 1254 (CAS RN 11097-69-1). and Aroclor 1260 (CAS RN
11096-82-5). The PQL shown is an average value (or PC8 congeners.
10 Toxaphene: This entry includes congener chemicals contained in technical toxaphene (CAS RN 8001-35-2), i.e..
chlorinated camphene.
" Xylene (total): This entry includes o-xylene (CAS RN 96-47-6), m-xylene (CAS RN 108-38-3), p-xylene (CAS RN 106-42-
3), and unspecified xylenes (dimethylbenzenes) (CAS RN 1330-20-7). PQLs lor method 8021 are 0.2 for o-xylene and 0.1 for
m- or p-xytene. The POL for m-xylene is 2.0 jxg/L by method 8020 or 8260.
PART 259STANDARDS FOR THE
TRACKING AND MANAGEMENT OF
MEDICAL WASTE
Subpart AGeneral
Sec.
259.1 Purpose, scope, and applicability.
259.2 Effective dates and duration of the
demonstration program.
Subpart BDefinition*
259.1(^ {Definitions.
Sec.
Subpart CCovered State*
259.20 States included in the demonstra-
tion program.
Subpart DRegulated Medical Watte
259.30 Definition of regulated medical
waste.
259.31 Mixtures.
Subpart EPre-Tran*port Requirement*
259.39 Applicability.
259.40 Segregation requirements.
-------
-------
ATTACHMENT H
-------
and facilities for conservation of energy or mate-
rials which contribute to the waste stream or for
the recovery of energy and materials from munic-
ipal waste and make recommendations to appro-
priate governmental authorities for overcoming
such impediments;
(C) assist municipalities within the State in de-
veloping plans, programs, and projects to con- -
serve resources or recover energy and materials
from municipal waste; and
(D) coordinate the resource conservation and
recovery planning under subparagraph (C).
(2) The analysis referred to in paragraph (1)(A)
shall include
(A) the evaluation of, and establishment of pri-
orities among, market opportunities for industrial
and commercial users of all types (including pub-
lic utilities and industrial parks) to utilize energy
and materials recovered from municipal waste;
(B) comparisons of the relative costs of energy
recovered from municipal waste in relation to the
costs of energy derived from fossil fuels and
other sources;
(C) studies of the transportation and storage
problems and other problems associated with the
development of energy and materials recovery
technology, including curbside source separation;
(D) the evaluation and establishment of priori-
ties among ways of conserving energy or materi-
als which contribute to the waste stream;
(E) comparison of the relative total costs be-
tween conserving resources and disposing of or
recovering such waste; and
(F) studies of impediments to resource conser-
vation or recovery, including business practices,
transportation requirements, or storage difficul-
ties.
Such studies and analyses shall also include studies
of other sources of solid waste from which energy
and materials may be recovered or minimized.
-------
that all existing disposal facilities or sites for solid
waste in such State which are open dumps listed in
the inventory under subsection (b) of this section
shall comply with such measures as may be promul-
gated by the Administrator to eliminate health haz-
ards and minimize potential health hazards. Each
such plan shall establish, for any entity which dem-
onstrates that it has considered other public or
private alternatives for solid waste management to
comply with the prohibition on open dumping and is
unable to utilize such alternatives to so comply, a
timetable or schedule for compliance for such prac-
tice or disposal of solid waste which specifies a
schedule of remedial measures, including an en-
forceable sequence of actions or operations, leading
to compliance with the prohibition on open dumping
of solid waste within a reasonable time (not to
exceed 5 years from the date of publication of
criteria under section 6907(a)(3) of this title).
(b) Inventory
To assist the States in complying with section
6943(a)(3) of this title, not later than one year after
promulgation of regulations under section 6944 of
this title, the Administrator, with the cooperation of
the Bureau of the Census shall publish an inventory
of all disposal facilities or sites in the United States
which are open dumps within the meaning of this
chapter.
(c) Control of hazardous disposal
(1)(A) Not later than 36 months after November
8, 1984, each State shall adopt and implement a
permit program or other system of prior approval
and conditions to assure that each solid waste
management facility within such State which may
receive hazardous household waste or hazardous
waste due to the provision of section 6921(d) of this
title for small quantity generators (otherwise not
subject to the requirement for a permit under sec-
tion 6925 of this title) will comply with the applica-
ble criteria promulgated under section 6944(a) and
6907(a)(3) of this title.
(B) Not later than eighteen months after the
promulgation of revised criteria under section
6944(a) of this title (as required by section 6949a(c)
of this title), each State shall adopt and implement a
permit program or other system or 1 prior approval
and conditions, to assure that each solid waste
management facility within such State which may
receive hazardous household waste or hazardous
waste due to the provision of section 6921(d) of this
title for small quantity generators (otherwise not
subject to the requirement for a permit under sec-
tion 6925 of this title) will comply with the criteria
revised under section 6944(a) of this title.
(C) The Administrator shall determine whether
each State has developed an adequate program un-
der this paragraph. The Administrator may make
such a determination in conjunction with approval,
disapproval or partial approval of a State plan under
- section 6947 of this title.
(2)(A) In any State that the Administrator deter-
mines has not adopted an adequate program for
such facilities under paragraph (1)(B) by the date
provided in such paragraph, the Administrator may
use the authorities available under sections 6927
and 6928 of this title to enforce the prohibition
contained in subsection (a) of this section with re-
spect of such facilities.
(B) For purposes of this paragraph, the term
"requirement of this subchapter" in section 6928 of
this title shall be deemed to include criteria promul-
gated by the Administrator under sections 6907(aX3)
and 6944(a) of this title, and the term "hazardous
wastes" in section 6927 of this title shall be deemed
to include solid waste at facilities that may handle
hazardous household wastes or hazardous wastes
from small quantity generators.
(Pub.L. 89-272, Title II, ง 4005, as added Oct 21, 1976,
Pub.L. 94-580, ง 2, 90 Stat. 2815, and amended Oct 21,
1980, Pub.L. 96482, ง 19(a), (b), 94 Stat. 2345; Nov. 8,
1984, Pub.L 98-616, Title III, ง 302(c). Title IV, ง 403(c),
Title V, ง 502(c), 98 Stat 3268, 3272, 3276.)
1 So in original. Probably should be "of.
ง 6946. Procedure for development and
implementation of State plan
[SWDA ง 4006]
(a) Identification of regions
Within one hundred and eighty days after publica-
tion of guidelines under section 6942(a) of this title
(relating to identification of regions), the Governor
of each State, after consultation with local elected
officials, shall promulgate regulations based on
such guidelines identifying the boundaries of each
area within the State which, as a result of urban
concentrations, geographic conditions, markets, and
other factors, is appropriate for carrying out region-
al solid waste management. Such regulations may
be modified from time to time (identifying additional
or different regions) pursuant to such guidelines.
(b) Identification of State and local agencies and re-
sponsibilities
(1) Within one hundred and eighty days after the
Governor promulgates regulations under subsection
(a) of this section, for purposes of facilitating the
-------
-------
ATTACHMENT I
-------
ง 1288. Areawide waste treatment
management [FWPCA ง 208]
(a) Identification and designation of areas having sub-
stantial water quality control problems
For the purpose of encouraging and facilitating
the development and implementation of areawide
waste treatment management plans
(1) The Administrator, within ninety days after
October 18, 1972, and after consultation with ap-
propriate Federal, State, and local authorities,
shall by regulation publish guidelines for the iden-
tification of those areas which, as a result of
urban-industrial concentrations or other factors,
have substantial water quality control problems.
(2) The Governor of each State, within sixty
days after publication of the guidelines issued
pursuant to paragraph (1) of this subsection, shall
identify each area within the State which, as a
result of urban-industrial concentrations or other
factors, has substantial water quality control
problems. Not later than one hundred and twen-
ty days following such identification and after
consultation with appropriate elected and other
officials of local governments having jurisdiction
in such areas, the Governor shall designate (A)
the boundaries of each such area, and (B) a single
representative organization, including elected offi-
cials from local governments or their designees,
capable of developing effective areawide waste
treatment management plans for such area. The
Governor may in the same manner at any later
time identify any additional area (or modify an
existing area) for which he determines areawide
waste treatment management to be appropriate,
designate the boundaries of such area, and desig-
nate an organization capable of developing effec-
tive areawide waste treatment management plans
for such area.
(3) With respect to any area which, pursuant to
the guidelines published under paragraph (1) of
this subsection, is located in two or more States,
the Governors of the respective States shall con-
sult and cooperate in carrying out the provisions
of paragraph (2), with a view toward designating
the boundaries of the interstate area having com-
mon water quality control problems and for which
areawide waste treatment management plans
would be most effective, and toward designating,
within one hundred and eighty days after publica-
tion of guidelines issued pursuant to paragraph
(1) of this subsection, of a single representative
organization capable of developing effective area-
wide waste treatment management plans for such
area.
(4) If a Governor does not act, either by desig-
nating or determining not to make a designation
under paragraph (2) of this subsection, within the
time required by such paragraph, or if, in the case
of an interstate area, the Governors of the States
involved do not designate a planning organization
within the time required by paragraph (3) of this
subsection, the chief elected officials of local
governments within an area may by agreement j
designate (A) the boundaries for such an area, !
and (B) a single representative organization in- i
eluding elected officials from such local govern-
ments, or their designees, capable of developing
an areawide waste treatment management plan
for such area.
(5) Existing regional agencies may be designatr
ed under paragraphs (2), (3), and (4) of this sub- ;
section. !
(6) The State shall act as a planning agency for
all portions of such State which are not designat-
ed under paragraphs (2), (3), or (4) of this subsec-
tion.
(7) Designations under this subsection shall be
subject to the approval of the Administrator.
(b) Planning process
(1)(A) Not later than one year after the date of
designation of any organization under subsection (a)
of this section such organization shall have in opera-
tion a continuing areawide waste treatment
management planning process consistent with sec-
tion 1281 of this title. Plans prepared in accordance
with this process shall contain alternatives for
waste treatment management, and be applicable to
all wastes generated within the area involved. The
initial plan prepared in accordance with such pro-
cess shall be certified by the Governor and sub-
mitted to the Administrator not later than two years
after the planning process is in operation.
(B) For any agency designated after 1975 under
subsection (a) of this section and for all portions of:
a State for which the State is required to act as the'
-------
planning agency in accordance with subsection (aX6)
of this section, the initial plan prepared in accord-
ance with such process shall be certified by the
Governor and submitted to the Administrator not
later than three years after the receipt of the initial
grant award authorized under subsection (f) of this
section.
(2) Any plan prepared under such process shall
include, but not be limited to
(A) the identification of treatment works neces-
sary to meet the anticipated municipal and indus-
trial waste treatment needs of the area over a
twenty-year period, annually updated (including
an analysis of alternative waste treatment sys-
tems), including any requirements for the acquisi-
tion of land for treatment purposes; the neces-
sary waste water collection and urban storm wa-
ter runoff systems; and a program to provide the
necessary financial arrangements for the develop-
ment of such treatment works, and an identifica-
tion of open space and recreation opportunities
that can be expected to result from improved
water quality, including consideration of potential
use of lands associated with treatment works and
increased access to water-based recreation;
(B) the establishment of construction priorities
for such treatment works and time schedules for
the initiation and completion of all treatment
works;
(C) the establishment of a regulatory program
to
(i) implement the waste treatment manage-
ment requirements of section 1281(c) of this
title,
(ii) regulate the location, modification, and
construction of any facilities within such area
which may result in any discharge in such area,
and
(iii) assure that any industrial or commercial
wastes discharged into any treatment works in
such area meet applicable pre treatment require-
ments;
(D) the identification of those agencies neces-
sary to construct, operate, and maintain all facili-
ties required by the plan and otherwise to carry
out the plan;
(E) the identification of the measures necessary
to carry out the plan (including financing), the
period of time necessary to carry out the plan, the
costs of carrying out the plan within such time,
and the economic, social, and environmental im-
pact of carrying out the plan within such time;
(F) a process to (i) identify, if appropriate,
agriculturally and silviculturally related nonpoint
sources of pollution, including return flows from
irrigated agriculture, and their cumulative ef-
fects, runoff from manure disposal areas, and
from land used for livestock and crop production,
and (ii) set forth procedures and methods (includ-
ing land use requirements) to control to the ex-
tent feasible such sources;
(G) a process to (i) identify, if appropriate,
mine-related sources of pollution including new,
current, and abandoned surface and underground
mine runoff, and (ii) set forth procedures and
methods (including land use requirements) to con-
trol to the extent feasible such sources;
(H) a process to (i) identify construction activity
related sources of pollution, and (ii) set forth
procedures and methods (including land use re-
quirements) to control to the extent feasible such
sources;
(I) a process to (i) identify, if appropriate, salt
water intrusion into rivers, lakes, and estuaries
resulting from reduction of fresh water flow from
any cause, including irrigation, obstruction,
ground water extraction, and diversion, and (ii)
set forth procedures and methods to control such
intrusion to the extent feasible where such proce-
dures and methods are otherwise a part of the
waste treatment management plan;
(J) a process to control the disposition of all
residual waste generated in such area which could
affect water quality; and
(K) a process to control the disposal of pollu-
tants on land or in subsurface excavations within
such area to protect ground and surface water
quality.
(3) Areawide waste treatment management plans
shall be certified annually by the Governor or his
designee (or Governors or their designees, where
more than one State is involved) as being consistent
with applicable basin plans and such areawide waste
treatment management plans shall be submitted to
the Administrator for his approval.
(4)(A) Whenever the Governor of any State deter-
mines (and notifies the Administrator) that consist-
ency with a statewide regulatory program under
section 1313 of this title so requires, the require-
ments of clauses (F) through (K) of paragraph (2) of
this subsection shall be developed and submitted by
the Governor to the Administrator for approval for
application to a class or category of activity
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(B) Any program submitted under subparagraph
(A) of this paragraph which, in whole or in part, is
to control the discharge or other placement of
dredged or fill material into the navigable waters
shall include the following:
(1) A consultation process which includes the
State agency with primary jurisdiction over fish
and wildlife resources.
(ii) A process to identify and manage the dis-
charge or other placement of dredged or fill mate-
rial which adversely affects navigable waters,
which shall complement and be coordinated with a
State program under section 1344 of this title
conducted pursuant to this chapter.
(Hi) A process to assure that any activity con-
ducted pursuant to a best management practice
will comply with the guidelines established under
section 1344(bXl) of this title, and sections 1317
and 1343 of this title.
(iv) A process to assure that any activity con-
ducted pursuant to a best management practice
can be terminated or modified for cause including,
but not limited to, the following:
(I) violation of any condition of the best
management practice;
(II) change in any activity that requires ei-
ther a temporary or permanent reduction or
elimination of the discharge pursuant to the
best management practice.
(v) A process to assure continued coordination
with Federal and Federal-State water-related
planning and reviewing processes, including the
National Wetlands Inventory.
(C) If the Governor of a State obtains approval
from the Administrator of a statewide regulatory
program which meets the requirements of subpara-
graph (B) of this paragraph and if such State is
administering a permit program under section 1344
of this title, no person shall be required to obtain an
individual permit pursuant to such section, or to
comply with a general permit issued pursuant to
such section, with respect to any appropriate activi-
ty within such State for which a best management
practice has been approved by the Administrator
under the program approved by the Administrator
pursuant to this paragraph.
(D)(i) Whenever the Administrator determines
after public hearing that a State is not administer-
ing a program approved under this section in ac-
cordance with the requirements of this section, the
Administrator shall so notify the State, and if appro-
priate corrective action is not taken within a reason-
able time, not to exceed ninety days, the Adminis-
trator shall withdraw approval of such program.
The Administrator shall not withdraw approval of
any such program unless he shall first have notified
the State, and made public, in writing, the reasons
for such withdrawal.
(ii) In the case of a State with a program sub-
mitted and approved under this paragraph, the Ad-
ministrator shall withdraw approval of such pro-
gram under this subparagraph only for a substan-
tial failure of the State to administer its program in
accordance with the requirements of this para-
graph.
(c) Regional operating agencies
(1) The Governor of each State, in consultation
with the planning agency designated under subsec-
tion (a) of this section, at the time a plan is sub-
mitted to the Administrator, shall designate one or
more waste treatment management agencies (which
may be an existing or newly created local, regional,
or State agency or political subdivision) for each
area designated under subsection (a) of this section
and submit such designations to the Administrator.
(2) The Administrator shall accept any such desig-
nation, unless, within 120 days of such designation,
he finds that the designated management agency
(or agencies) does not have adequate authority
(A) to carry out appropriate portions of an
areawide waste treatment management plan de-
veloped under subsection (b) of this section;
(B) to manage effectively waste treatment
works and related facilities serving such area in
conformance with any plan required by subsec-
tion (b) of this section;
(C) directly or by contract, to design and con-
struct new works, and to operate and maintain
new and existing works as required by any plan
developed pursuant to subsection (b) of this sec-
tion;
(D) to accept and utilize grants, or other funds
from any source, for waste treatment manage-
ment purposes;
(E) to raise revenues, including the assessment
of waste treatment charges;
(F) to incur short- and long-term indebtedness;
(G) to assure in implementation of an areawide
waste treatment management plan that each par-
ticipating community pays its proportionate share
of treatment costs;
(H) to refuse to receive any wastes from any
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not comply with any provisions of an approved
plan under this section applicable to such area;
and
(I) to accept for treatment industrial wastes,
(d) Conformity of works with area plan
After a waste treatment management agency
having the authority required by subsection (c) of
this section has been designated under such subsec-
tion for an area and a plan for such area has been
approved under subsection (b) of this section, the
Administrator shall not make any grant for con-
struction of a publicly owned treatment works un-
der section 1281(gXl) of this title within such area
except to such designated agency and for works in
conformity with such plan.
(e) Permits not to conflict with approved plans
No permit under section 1342 of this title shall be
issued for any point source which is in conflict with
a plan approved pursuant to subsection (b) of this
section.
(0 Grants
(1) The Administrator shall make grants to any
agency designated under subsection (a) of this sec-
tion for payment of the reasonable costs of develop-
ing and operating a continuing areawide waste
treatment management planning process under sub-
section (b) of this section.
(2) For the two-year period beginning on the date
the first grant is made under paragraph (1) of this
subsection to an agency, if such first grant is made
before October 1, 1977, the amount of each such
grant to such agency shall be 100 per centum of the
costs of developing and operating a continuing area-
wide waste treatment management planning pro-
cess under subsection (b) of this section, and there-
after the amount granted to such agency shall not
exceed 75 per centum of such costs in each succeed-
ing one-year period. In the case of any other grant
made to an agency under such paragraph (1) of this
subsection, the amount of such grant shall not
exceed 75 per centum of the costs of developing and
operating a continuing areawide waste treatment
management planning process in any year.
(3) Each applicant for a grant under this subsec-
tion shall submit to the Administrator for his ap-
proval each proposal for which a grant is applied for
under this subsection. The Administrator shall act
upon such proposal as soon as practicable after it
ha3 been submitted, and his approval of that propos-
al shall be deemed a contractual obligation of the
United States for the payment of its contribution to
such proposal, subject to such amounts as are pro-
vided in appropriation Acts. There is authorized to
be appropriated to carry out this subsection not to
exceed $50,000,000 for the fiscal year ending June
30, 1973, not to exceed $100,000,000 for the fiscal
year ending June 30, 1974, not to exceed
$150,000,000 per fiscal year for the fiscal years
ending June 30, 1975, September 30, 1977, Septem-
ber 30, 1978, September 30, 1979, and September 30,
1980, not to exceed $100,000,000 per fiscal year for
the fiscal years ending September 30, 1981, and
September 30, 1982, and such sums as may be
necessary for fiscal years 1983 through 1990.
(g) Technical assistance by Administrator
The Administrator is authorized, upon request of
the Governor or the designated planning agency,
and without reimbursement, to consult with, and
provide technical assistance to, any agency desig-
nated under subsection (a) of this section in the
development of areawide waste treatment manage-
ment plans under subsection (b) of this section.
(h) Technical assistance by Secretary of the Army
(1) The Secretary of the Army, acting through
the Chief of Engineers, in cooperation with the
Administrator is authorized and directed, upon re-
quest of the Governor or the designated planning
organization, to consult with, and provide technical
assistance to, any agency designed1 under subsec-
tion (a) of this section in developing and operating a
continuing areawide waste treatment management
planning process under subsection (b) of this sec-
tion.
(2) There is authorized to be appropriated to the
Secretary of the Army, to carry out this subsection,
not to exceed $50,000,000 per fiscal year for the
fiscal years ending June 30, 1973, and June 30, 1974.
(i) State best management practices program
(1) The Secretary of the Interior, acting through
the Director of the United States Fish and Wildlife
Service, shall, upon request of the Governor of a
State, and without reimbursement, provide technical
assistance to such State in developing a statewide
program for submission to the Administrator under
subsection (bX4)(B) of this section and in implement-
ing such program after its approval.
(2) There is authorized to be appropriated to the
Secretary of the Interior $6,000,000 to complete the
National Wetlands Inventory of the United States,
by December 31, 1981, and to provide information
from such Inventory to States as it becomes avail-
able to assist such States in the development and
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(j) Agricultural cost sharing
(1) The Secretary of Agriculture, with the concur-
rence of the Administrator, and acting through the
Soil Conservation Service and such other agencies
of the Department of Agriculture as the Secretary
may designate, is authorized and directed to estab-
lish and administer a program to enter into con-
tracts, subject to such amounts as are provided in
advance by appropriation acts, of not less than five
years nor more than ten years with owners and
operators having control of rural land for the pur-
pose of installing and maintaining measures incor-
porating best management practices to control non-
point source pollution for improved water quality in
those States or areas for which the Administrator
has approved a plan under subsection (b) of this
section where the practices to which the contracts
apply are certified by the management agency des-
ignated under subsection (cXl) of this section to be
consistent with such plans and will result in im-
proved water quality. Such contracts may be en-
tered into during the period ending not later than
September 31, 1988. Under such contracts the land
owner or operator shall agree
(i) to effectuate a plan approved by a soil
conservation district, where one exists, under this
section for his farm, ranch, or other land substan-
tially in accordance with the schedule outlined
therein unless any requirement thereof is waived
or modified by the Secretary;
(ii) to forfeit all rights to further payments or
grants under the contract and refund to the Unit-
ed States all payments and grants received there-
under, with interest, upon his violation of the
contract at any stage during the time he has
control of the land if the Secretary, after consid-
ering the recommendations of the soil conserva-
tion district, where one exists, and the Adminis-
trator, determines that such violation is of such a
nature as to warrant termination of the contract,
or to make refunds or accept such payment ad-
justments as the Secretary may deem appropriate
if he determines that the violation by the owner
or operator does not warrant termination of the
contract;
(iii) upon transfer of his right and interest in
the farm, ranch, or other land during the contract
period to forfeit all rights to further payments or
grants under the contract and refund to the Unit-
ed States all payments or grants received there-
under, with interest, unless the transferee of any
such land agrees with the Secretary to assume all
obligations of the contract;
(iv) not to adopt any practice specified by the
Secretary on the advice of the Administrator in
the contract as a practice which would tend to
defeat the purposes of the contract;
(v) to such additional provisions as the Secre-
tary determines are desirable and includes in the
contract to effectuate the purposes of the pro-
gram or to facilitate the practical administration
of the program.
(2) In return for such agreement by the land-
owner or operator the Secretary shall agree to
provide technical assistance and share the cost of
carrying out those conservation practices and mea-
sures set forth in the contract for which he deter-
mines that cost sharing is appropriate and in the
public interest and which are approved for cost
sharing by the agency designated to implement the
plan developed under subsection (b) of this section.
The portion of such cost (including labor) to be
shared shall be that part which the Secretary deter-
mines is necessary and appropriate to effectuate the
installation of the water quality management prac-
tices and measures under the contract, but not to
exceed 60 per centum of the total cost of the mea-
sures set forth in the contract; except the Secretary
may increase the matching cost share where he
determines that (1) the main benefits to be derived
from the measures are related to improving offsite
water quality, and (2) the matching share require-
ment would place a burden on the landowner which
would probably prevent him from participating in
the program.
(3) The Secretary may terminate any contract
with a landowner or operator by mutual agreement
with the owner or operator if the Secretary deter-
mines that such termination would be in the public
interest, and may agree to such modification of
contracts previously entered into as he may deter-
mine to be desirable to carry out the purposes of
the program or facilitate the practical administra-
tion thereof or to accomplish equitable treatment
with respect to other conservation, land use, or
water quality programs.
(4) In providing assistance under this subsection
the Secretary will give priority to those areas and
sources that have the most significant effect upon
water quality. Additional investigations or plans
may be made, where necessary, to supplement ap-
proved water quality management plans, in order to
determine priorities.
(5) The Secretary shall, where practicable, enter
into agreements with soil conservation districts,
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water quality agencies to administer all or part of
the program established in this subsection under
regulations developed by the Secretary. Such
agreements shall provide for the submission of such
reports as the Secretary deems necessary, and for
payment by the United States of such portion of the
costs incurred in the administration of the program
as the Secretary may deem appropriate.
(6) The contracts under this subsection shall be
entered into only in areas where the management
agency designated under subsection (cXl) of this
section assures an adequate level of participation by
owners and operators having control of rural land in
such areas. Within such areas the local soil conser-
vation district, where one exists, together with the
Secretary of Agriculture, will determine the priority
of assistance among individual land owners and
operators to assure that the most critical water
quality problems are addressed.
(7) The Secretary, in consultation with the Admin-
istrator and subject to section 1314(k) of this title,
shall, not later than September 30,1978, promulgate
regulations for carrying out this subsection and for
support and cooperation with other Federal and non-
Federal agencies for implementation of this subsec-
tion.
(8) This program shall not be used to authorize or
finance projects that would otherwise be eligible for
assistance under the terms of Public Law 83-566
[16 U.S.C.A. ง 1001 et seq.].
(9) There are hereby authorized to be appropriat-
ed to the Secretary of Agriculture $200,000,000 for
fiscal year 1979, $400,000,000 for fiscal year 1980,
$100,000,000 for fiscal year 1981, $100,000,000 for
fiscal year 1982, and such sums as may be neces-
sary for fiscal years 1983 through 1990, to carry out
this subsection. The program authorized under this
subsection shall be in addition to, and not in substi-
tution of, other programs in such area authorized
by this or any other public law.
(June 30, 1948, c. 758, Title II, ง 208, as added Oct 18,
1972, Pub.L. 92-500, ง 2, 86 Stat 839, and amended Dec.
27, 1977, Pub.L. 95-217, งง 4(e). 31, 32, 33(a). 34, 35, 91
Stat. 1566, 1576-1579, Oct. 21, 1980, Pub.L. 96-183, ง 1(d),
(e), 94 Stat. 2360; Feb. 4, 1987, Pub.L. 100-4, Title I,
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ATTACHMENT J
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(b) Procedures and guidelines
The Administrator shall by regulation establish
any procedures and guidelines which the Adminis-
trator deems necessary to carry out this section.
Such regulations shall require the application to
such discharge of each criterion, factor, procedure,
and requirement applicable to a permit issued under
section 1342 of this title, as the Administrator deter-
mines necessary to carry out the objective of this
chapter.
(c) State administration
Each State desiring to administer its own permit
program within its jurisdiction for discharge of a
specific pollutant or pollutants under controlled con-
ditions associated with an approved aquaculture
project may do so if upon submission of such pro-
gram the Administrator determines such program is
adequate to carry out the objective of this chapter.
(June 30, 1948, c. 758, Title III, ง 318, as added Oct 18,
1972, Pub.L. 92-500, ง 2, 86 Stat. 877, and amended Dec.
27, 1977, Pub.L. 95-217, ง 63, 91 Stat 1599.)
Cross References
Enforcement of provisions of this section, see section 1319 of this
title.
Illegality of pollutant discharges except as in compliance with this
section, see section 1311 of this title.
Permit for discharge of pollutants except as provided in this
section, see section 1342 of this title.
Code of Federal Regulations
Environmental Protection Agency administered permit programs:
the National Pollutant Discharge Elimination System, see 40
CFR 122.1 et seq.
State program requirements, see 40 CFR 123.1 et seq.
ง 1329. Nonpoint source management pro-
grams [FWPCA ง 319]
(a) State assessment reports
(1) Contents
The Governor of each State shall, after notice
and opportunity for public comment, prepare and
submit to the Administrator for approval, a report
which
(A) identifies those navigable waters within
the State which, without additional action to
control nonpoint sources of pollution, cannot
reasonably be expected to attain or maintain
applicable water quality standards or the goals
and requirements of this chapter;
(B) identifies those categories and subcate-
gories of nonpoint sources or, where appropri-
ate, particular nonpoint sources which add sig-
nificant pollution to each portion of the naviga-
ble waters identified under subparagraph (A) in
amounts which contribute to such portion not
meeting such water quality standards or such
goals and requirements;
(C) describes the process, including intergov-
ernmental coordination and public participation,
for identifying best management practices and
measures to control each category and subcate-
gory of nonpoint sources and, where appropri-
ate, particular nonpoint sources identified under
subparagraph (B) and to reduce, to the maxi-
mum extent practicable, the level of pollution
resulting from such category, subcategory, or
source; and
(D) identifies and describes State and local
programs for controlling pollution added from
nonpoint sources to, and improving the quality
of, each such portion of the navigable waters,
including but not limited to those programs
which are receiving Federal assistance under
subsections (h) and (i) of this section.
(2) Information used in preparation
In developing the report required by this sec-
tion, the State (A) may rely upon information
developed pursuant to sections 1288, 1313(e),
1314(f), 1315(b), and 1324 of this title, and other
information as appropriate, and (B) may utilize
appropriate elements of the waste treatment
management plans developed pursuant to sections
1288(b) and 1313 of this title, to the extent such
elements are consistent with and fulfill the re-
quirements of this section.
(b) State management programs
(1) In general
The Governor of each State, for that State or in
combination with adjacent States, shall, after no-
tice and opportunity for public comment, prepare
and submit to the Administrator for approval a
management program which such State proposes
to implement in the first four fiscal years begin-
ning after the date of submission of such manage-
ment program for controlling pollution added
from nonpoint sources to the navigable waters
within the State and improving the quality of
such waters.
(2) Specific contents
Each management program proposed for imple-
mentation under this subsection shall include each
of the following:
(A) An identification of the best manage-
ment practices and measures which will be un-
dertaken to reduce pollutant loadings resulting
from each category, subcategory, or particular
-------
(1KB), taking into account the impact of the
practice on ground water quality.
(B) An identification of programs (including,
as appropriate, nonregulatory or regulatory
programs for enforcement, technical assistance,
financial assistance, education, training, tech-
nology transfer, and demonstration projects) to
achieve implementation of the best manage-
ment practices by the categories, subcategories,
and particular nonpoint sources designated un-
der subparagraph (A).
(C) A schedule containing annual milestones
for (i) utilization of the program implementation
methods identified in subparagraph (B), and (ii)
implementation of the best management prac-
tices identified in subparagraph (A) by the cate-
gories, subcategories, or particular nonpoint
sources designated under paragraph (1)(B).
Such schedule shall provide for utilization of
the best management practices at the earliest
practicable date.
(D) A certification of the attorney general of
the State or States (or the chief attorney of any
State water pollution control agency which has
independent legal counsel) that the laws of the
State or States, as the case may be, provide
adequate authority to implement such manage-
ment program or, if there is not such adequate
authority, a list of such additional authorities as
will be necessary to implement such manage-
ment program. A schedule and commitment by
the State or States to seek such additional
authorities as expeditiously as practicable.
(E) Sources of Federal and other assistance
and funding (other than assistance provided
under subsections (h) and (i) of this section)
which will be available in each of such fiscal
years for supporting implementation of such
practices and measures and the purposes for
which such assistance will be used in each of
such fiscal years.
(F) An identification of Federal financial as-
sistance programs and Federal development
projects for which the State will review individ-
ual assistance applications or development
projects for their effect on water quality pursu-
ant to the procedures set forth in Executive
Order 12372 as in effect on September 17, 1983,
to determine whether such assistance applica-
tions or development projects would be consist-
ent with the program prepared under this sub-
section; for the purposes of this subparagraph,
identification shall not be limited to the assist-
ance programs or development projects subject
to Executive Order 12372 but may include any
programs listed in the most recent Catalog of
Federal Domestic Assistance which may have
an effect on the purposes and objectives of the
State's nonpoint source pollution management
program.
(3) Utilization of local and private experts
In developing and implementing a management
program under this subsection, a State shall, to
the maximum extent practicable, involve local
public and private agencies and organizations
which have expertise in control of nonpoint
sources of pollution.
(4) Development on watershed basis
A State shall, to the maximum extent practica-
ble, develop and implement a management pro-
gram under this subsection on a watershed-by-
watershed basis within such State.
(c) Administrative provisions
(1) Cooperation requirement
Any report required by subsection (a) of this
section and any management program and report
required by subsection (b) of this section shall be
developed in cooperation with local, substate re-
gional, and interstate entities which are actively
planning for the implementation of nonpoint
source pollution controls and have either been
certified by the Administrator in accordance with
section 1288 of this title, have worked jointly with
the State on water quality management planning
under section 1285(j) of this title, or have been
designated by the State legislative body or Gover-
nor as water quality management planning agen-
cies for their geographic areas.
(2) Time period for submission of reports and
management programs
Each report and management program shall be
submitted to the Administrator during the
18-month period beginning on February 4, 1987.
(d) Approval or disapproval of reports and management
programs
(1) Deadline
Subject to paragraph (2), not later than 180
days after the date of submission to the Adminis-
trator of any report or management program
under this section (other than subsections (h), (i),
and (k) of this section), the Administrator shall
either approve or disapprove such report or
management program, as the case may be. The
Administrator may approve a portion of a
management program under this subsection. If
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management program, or portion of a manage-
ment program in such 180-day period, such re-
port, management program, or portion shall be
deemed approved for purposes of this section.
(2) Procedure for disapproval
If, after notice and opportunity for public com-
ment and consultation with appropriate Federal
and State agencies and other interested persons,
the Administrator determines that
(A) the proposed management program or
any portion thereof does not meet the require-
ments of subsection (b)(2) of this section or is
not likely to satisfy, in whole or in part, the
goals and requirements of this chapter;
(B) adequate authority does not exist, or ade-
quate resources are not available, to implement
such program or portion;
(C) the schedule for implementing such pro-
gram or portion is not sufficiently expeditious;
or
(D) the practices and measures proposed in
such program or portion are not adequate to
reduce the level of pollution in navigable waters
in the State resulting from nonpoint sources
and to improve the quality of navigable waters
in the State;
the Administrator shall within 6 months of the
receipt of the proposed program notify the State
of any revisions or modifications necessary to
obtain approval. The State shall thereupon have
an additional 3 months to submit its revised
management program and the Administrator
shall approve or disapprove such revised program
within three months of receipt.
(3) Failure of State to submit report
If a Governor of a State does not submit the
report required by subsection (a) of this section
within the period specified by subsection (c)(2) of
this section, the Administrator shall, within 30
months after February 4, 1987, prepare a report
for such State which makes the identifications
required by paragraphs (1)(A) and (1)(B) of sub-
section (a) of this section. Upon completion of the
requirement of the preceding sentence and after
notice and opportunity for comment, the Adminis-
trator shall report to Congress on his actions
pursuant to this section.
(e) Local management programs; technical assistance
If a State fails to submit a management program
under subsection (b) of this section or the Adminis-
trator does not approve such a management pro-
gram, a local public agency or organization which
has expertise in, and authority to, control water
pollution resulting from nonpoint sources in any
area of such State which the Administrator deter-
mines is of sufficient geographic size may, with
approval of such State, request the Administrator to
provide, and the Administrator shall provide, techni-
cal assistance to such agency or organization in
developing for such area a management program
which is described in subsection (b) of this section
and can be approved pursuant to subsection (d) of
this section. After development of such manage-
ment program, such agency or organization shall
submit such management program to the Adminis-
trator for approval. If the Administrator approves
such management program, such agency or orga-
nization shall be eligible to receive financial assist-
ance under subsection (h) of this section for imple-
mentation of such management program as if such
agency or organization were a State for which a
report submitted under subsection (a) of this section
and a management program submitted under sub-
section (b) of this section were approved under this
section. Such financial assistance shall be subject
to the same terms and conditions as assistance
provided to a State under subsection (h) of this
section.
(f) Technical assistance for States
Upon request of a State, the Administrator may
provide technical assistance to such State in devel-
oping a management program approved under sub-
section (b) of this section for those portions of the
navigable waters requested by such State.
(g) Interstate management conference
(1) Convening of conference; notification; purpose
If any portion of the navigable waters in any
State which is implementing a management pro-
gram approved under this section is not meeting
applicable water quality standards or the goals
and requirements of this chapter as a result, in
whole or in part, of pollution from nonpoint
sources in another State, such State may petition
the Administrator to convene, and the Administra-
tor shall convene, a management conference of all
States which contribute significant pollution re-
sulting from nonpoint sources to such portion.
If, on the basis of information available, the Ad-
ministrator determines that a State is not meeting
applicable water quality standards or the goals
and requirements of this chapter as a result, in
whole or in part, of significant pollution from
nonpoint sources in another State, the Adminis-
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tor may convene a management conference under
this paragraph not later than 180 days after giv-
ing such notification, whether or not the State
which is not meeting such standards requests
such conference. The purpose of such conference
shall be to develop an agreement among such
States to reduce the level of pollution in such
portion resulting from nonpoint sources and to
improve the water quality of such portion. Noth-
ing in such agreement shall supersede or abro-
gate rights to quantities of water which have
been established by interstate water compacts.
Supreme Court decrees, or State water laws.
This subsection shall not apply to any pollution
which is subject to the Colorado River Basin
Salinity Control Act [43 U.S.C.A. ง 1571 et seq.].
The requirement that the Administrator convene
a management conference shall not be subject to
the provisions of section 1365 of this title.
(2) State management program requirement
To the extent that the States reach agreement
through such conference, the management pro-
grams of the States which are parties to such
agreements and which contribute significant pol-
lution to the navigable waters or portions thereof
not meeting applicable water quality standards or
goals and requirements of this chapter will be
revised to reflect such agreement Such manage-
ment programs shall be consistent with Federal
and State law.
(h) Grant program
(1) Grants for implementation of management pro-
grams
Upon application of a State for which a report
submitted under subsection (a) of this section and
a management program submitted under subsec-
tion (b) of this section is approved under this
section, the Administrator shall make grants, sub-
ject to such terms and conditions as the Adminis-
trator considers appropriate, under this subsec-
tion to such State for the purpose of assisting the
State in implementing such management pro-
gram. Funds reserved pursuant to section
1285(jX5) of this title may be used to develop and
implement such management program.
(2) Applications
An application for a grant under this subsection
in any fiscal year shall be in such form and shall
contain such other information as the Administra-
tor may require, including an identification and
description of the best management practices and
measures which the State proposes to assist, en-
courage, or require in such year with the Federal
assistance to be provided under the grant
(3) Federal share
The Federal share of the cost of each manage-
ment program implemented with-Federal assist-
ance under this subsection in any fiscal year shall
not exceed 60 percent of the cost incurred by the
State in implementing such management program
and shall be made on condition that the non-
Federal share is provided from non-Federal
sources.
(4) Limitation on grant amounts
Notwithstanding any other provision of this
subsection, not more than 15 percent of the
amount appropriated to carry out this subsection
may be used to make grants to any one State,
including any grants to any local public agency or
organization with authority to control pollution
from nonpoint sources in any area of such State.
(5) Priority for effective mechanisms
For each fiscal year beginning after September
30, 1987, the Administrator may give priority in
making grants under this subsection, and shall
give consideration in determining the Federal
share of any such grant, to States which have
implemented or are proposing to implement
management programs which will
(A) control particularly difficult or serious
nonpoint source pollution problems, including,
but not limited to, problems resulting from
mining activities;
(B) implement innovative methods or practic-
es for controlling nonpoint sources of pollution,
including regulatory programs where the Ad-
ministrator deems appropriate;
(C) control interstate nonpoint source pollu-
tion problems; or
(D) carry out ground water quality protec-
tion activities which the Administrator deter-
mines are part of a comprehensive nonpoint
source pollution control program, including re-
search, planning, ground water assessments,
demonstration programs, enforcement, techni-
cal assistance, education, and training to pro-
. tect ground water quality from nonpoint
sources of pollution.
(6) Availability for obligation
The funds granted to each State pursuant to
this subsection in a fiscal year shall remain avail-
able for obligation by such State for the fiscal
year for which appropriated. The amount of any
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year shall be available to the Administrator for
granting to other States under this subsection in
the next fiscal year.
(7) Limitation on use of funds
States may use funds from grants made pursu-
ant to this section for financial assistance to per-
sons only to the extent that such assistance is
related to the costs of demonstration projects.
(8) Satisfactory progress
No grant may be made under this subsection in
any fiscal year to a State which in the preceding
fiscal year received a grant under this subsection
unless the Administrator determines that such
State made satisfactory progress in such preced-
ing fiscal year in meeting the schedule specified
by such State under subsection (b)(2) of this sec-
tion.
(9) Maintenance of effort
No grant may be made to a State under this
subsection in any fiscal year unless such State
enters into such agreements with the Administra-
tor as the Administrator may require to ensure
that such State will maintain its aggregate ex-
penditures from all other sources for programs
for controlling pollution added to the navigable
waters in such State from nonpoint sources and
improving the quality of such waters at or above
the average level of such expenditures in its two
fiscal years preceding February 4, 1987.
(10) Request for information
The Administrator may request such informa-
tion, data, and reports as he considers necessary
to make the determination of continuing eligibility
for grants under this section.
(11) Reporting and other requirements
Each State shall report to the Administrator on
an annual basis concerning (A) its progress in
meeting the schedule of milestones submitted
pursuant to subsection (b)(2)(C) of this section,
and (B) to the extent that appropriate information
is available, reductions in nonpoint source pollu-
tant loading and improvements in water quality
for those navigable waters or watersheds within
the State which were identified pursuant to sub-
section (a)(1)(A) of this section resulting from
implementation of the management program.
(12) Limitation on administrative costs
For purposes of this subsection, administrative
costs in the form of salaries, overhead, or indirect
costs for services provided and charged against
activities and programs carried out with a grant
under this subsection shall not exceed in any
fiscal year 10 percent of the amount of the grant
in such year, except that costs of implementing
enforcement and regulatory activities, education,
training, technical assistance, demonstration
projects, and technology transfer programs shall
not be subject to this limitation.
(i) Grants for protecting groundwater quality
(1) Eligible applicants and activities
Upon application of a State for which a report
submitted under subsection (a) of this section and
a plan submitted under subsection (b) of this
section is approved under this section, the Admin-
istrator shall make grants under this subsection
to such State for the purpose of assisting such
State in carrying out groundwater quality protec-
tion activities which the Administrator determines
will advance the State toward implementation of a
comprehensive nonpoint source pollution control
program. Such activities shall include, but not be
limited to, research, planning, groundwater as-
sessments, demonstration programs, enforce-
ment, technical assistance, education and training
to protect the quality of groundwater and to
prevent contamination of grouhdwater from non-
point sources of pollution.
(2) Applications
An application for a grant under this subsection
shall be in such form and shall contain such
information as the Administrator may require.
(3) Federal share; maximum amount
The Federal share of the cost of assisting a
State in carrying out groundwater protection ac-
tivities in any fiscal year under this subsection
shall be 50 percent of the costs incurred by the
State in carrying out such activities, except that
the maximum amount of Federal assistance which
any State may receive under this subsection in
any fiscal year shall not exceed $150,000.
(4) Report
The Administrator shall include in each report
transmitted under subsection (m) of this section a
report on the activities and programs implement-
ed under this subsection during the preceding
fiscal year.
(j) Authorization of appropriations
There is authorized to be appropriated to carry
out subsections (h) and (i) of this section not to
exceed $70,000,000 for fiscal year 1988,
$100,000,000 per fiscal year for each of fiscal years
1989 and 1990, and $130,000,000 for fiscal year
1991; except that for each of such fiscal years not
to exceed $7,500,000 may be made available to carry
-------
ed pursuant to this subsection shall remain available
until expended.
(k) Consistency of other programs and projects with
management programs
The Administrator shall transmit to the Office of
Management and Budget and the appropriate Fed-
eral departments and agencies a list of those assist-
ance programs and development projects identified
by each State under subsection (b)(2)(F) of this
section for which individual assistance applications
and projects will be reviewed pursuant to the proce-
dures set forth in Executive Order 12372 as in
effect on September 17, 1983. Beginning not later
than sixty days after receiving notification by the
Administrator, each Federal department and agency
shall modify existing regulations to allow States to
review individual development projects and assist-
ance applications under the identified Federal assist-
ance programs and shall accommodate, according to
the requirements and definitions of Executive Order
12372, as in effect on September 17, 1983, the
concerns of the State regarding the consistency of
such applications or projects with the State nonpoint
source pollution management program.
(/) Collection of information
The Administrator shall collect and make avail-
able, through publications and other appropriate
means, information pertaining to management prac-
tices and implementation methods, including, but
not limited to, (1) information concerning the costs
and relative efficiencies of best management prac-
tices for reducing nonpoint source pollution; and (2)
available data concerning the relationship between
water quality and implementation of various
management practices to control nonpoint sources
of pollution.
(m) Reports of Administrator
(1) Annual reports
Not later than January 1, 1988, and each Janu-
ary 1 thereafter, the Administrator shall transmit
to the Committee on Public Works and Transpor-
tation of the House of Representatives and the
Committee on Environment and Public Works of
the Senate, a report for the preceding fiscal year
on the activities and programs implemented under
this section and the progress made in reducing
pollution in the navigable waters resulting from
nonpoint sources and improving the quality of
such waters.
(2) Final report
Not later than January 1, 1990, the Administra-
tor shall transmit to Congress a final report on
the activities carried out under this section. Such
report, at a minimum, shall
(A) describe the management programs be-
ing implemented by the States by types and
amount of affected navigable waters, catego-
ries and subcategories of nonpoint sources, and
types of best management practices being im-
plemented;
(B) describe the experiences of the States in
adhering to schedules and implementing best
management practices;
(C) describe the amount and purpose of
grants awarded pursuant to subsections (h) and
(i) of this section;
(D) identify, to the extent that information is
available, the progress made in reducing pollu-
tant loads and improving water quality in the
navigable waters;
(E) indicate what further actions need to be
taken to attain and maintain in those navigable
waters (i) applicable water quality standards,
and (ii) the goals and requirements of this chap-
ter;
(F) include recommendations of the Adminis-
trator concerning future programs (including
enforcement programs) for controlling pollution
from nonpoint sources; and
(G) identify the activities and programs of
departments, agencies, and instrumentalities of
the United States which are inconsistent with
the management programs submitted by the
States and recommend modifications so that
such activities and programs are consistent
with and assist the States in implementation of
such management programs.
(n) Set aside for administrative personnel
Not less than 5 percent of the funds appropriated
pursuant to subsection (j) of this section for any
fiscal year shall be available to the Administrator to
maintain personnel levels at the Environmental Pro-
tection Agency at levels which are adequate to
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ATTACHMENT K
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will not violate the applicable provisions of section
1311, 1312, 1313, 131G, or 1317 of this title.
(5) Any Federal license or permit with respect to
which a certification has been obtained under para-
graph (1) of this subsection may be suspended or
revoked by the Federal agency issuing such license
or permit upon the entering of a judgment under
this chapter that such facility or activity has been
operated in violation of the applicable provisions of
section 1311, 1312, 1313, 1316, or 1317 of this title.
(6) Except with respect to a permit issued under
section 1342 of this title, in any case where actual
construction of a facility has been lawfully com-
menced prior to April 3, 1970, no certification shall
be required under this subsection for a license or
permit issued after April 3, 1970, to operate such
facility, except that any such license or permit is-
sued without certification shall terminate April 3,
1973, unless prior to such termination date the
person having such license or permit submits to the
Federal agency which issued such license or permit
a certification and otherwise meets the require-
ments of this section.
[(7) Redesignated (6)].
(b) Compliance with other provisions of law setting
applicable water quality requirements
Nothing in this section shall be construed to limit
the authority of any department or agency pursuant
to any other provision of law to require compliance
with any applicable water quality requirements.
The Administrator shall, upon the request of any
Federal department or agency, or State or inter-
state agency, or applicant, provide, for the purpose
of this section, any relevant information on applica-
ble effluent limitations, or other limitations, stan-
dards, regulations, or requirements, or water quali-
ty criteria, and shall, when requested by any such
department or agency or State or interstate agency,
or applicant, comment on any methods to comply
with such limitations, standards, regulations, re-
quirements, or criteria.
(c) Authority of Secretary of the Army to permit use of
spoil disposal areas by Federal licensees or permit-
tees
In order to implement the provisions of this sec-
tion, the Secretary of the Army, acting through the
Chief of Engineers, is authorized, if he deems it to
be in the public interest, to permit the use of spoil
disposal areas under his jurisdiction by Federal li-
censees or permittees, and to make an appropriate
charge for such use. Moneys received from such
licensees or permittees shall be deposited in the
Treasury as miscellaneous receipts.
(d) Limitations and monitoring requirements of certifi-
cation
Any certification provided under this section shall
set forth any effluent limitations and other limita-
tions, and monitoring requirements necessary to
assure that any applicant for a Federal license or
permit will comply with any applicable effluent limi-
tations and other limitations, under section 1311 or
1312 of this title, standard of performance under
section 1316 of this title, or prohibition, effluent
standard, or pretreatment standard under section
1317 of this title, and with any other appropriate
requirement of State law set forth in such certifica-
tion, and shall become a condition on any Federal
license or permit subject to the provisions of this
section.
(June 30, 1948, c. 758, Title IV, ง 401, as added Oct 18,
1972, Pub.L. 92-500, ง 2, 86 Stat 877, and amended Dec.
27, 1977, Pub.L 95-217, งง 61(b), 64, 91 Stat 1598, 1599.)
Cross References
Citizen suits for violation of effluent standards, seซ section 1365 of
this title.
Licensing authority of any Federal agency under environmental
policy provisions, see section 1371 of this title.
Test procedures for analysis of pollutants to include factors Ui be
provided in any certification pursuant to this section, see
section 1314 of this title.
Library References
Health and Environment <ฃ=>25.7(13).
CJ.S. Health and Environment ง 107 et seq.
ง 1342. National pollutant discharge elim-
ination system [FWPCA ง 402]
(a) Permits for discharge of pollutants
(1) Except as provided in sections 1328 and 1344
of this title, the Administrator may, after opportuni-
ty for public hearing, issue a permit for the dis-
charge of any pollutant, or combination of pollu-
tants, notwithstanding section 1311(a) of this title,
upon condition that such discharge will meet either
(A) all applicable requirements under sections 1311,
1312, 1316, 1317, 1318, and 1343 of this title, or (B)
prior to the taking of necessary implementing ac-
tions relating to all such requirements, such condi-
tions as the Administrator determines are necessary
to carry out the provisions of this chapter.
(2) The Administrator shall prescribe conditions
for such permits to assure compliance with the
requirements of paragraph (1) of this subsection,
including conditions on data and information collec-
tion, reporting, and such other requirements as he
deems appropriate.
(3) The permit program of the Administrator un-
-------
issued thereunder, shall be subject to the same
terms, conditions, and requirements as apply to a
State permit program and permits issued thereun-
der under subsection (b) of this section.
(4) All permits for discharges into the navigable
waters issued pursuant to section 407 of this title
shall be deemed to be permits issued under this
subchapter, and permits issued under this subchap-
ter shall be deemed to be permits issued under
section 407 of this title, and shall continue in force
and effect for their term unless revoked, modified,
or suspended in accordance with the provisions of
this chapter.
(5) No permit for a discharge into the navigable
waters shall be issued under section 407 of this tltJe
after October 18, 1972. Each application for a
permit under section 407 of this title, pending on
October 18, 1972, shall be deemed to be an applica-
tion for a permit under this section. The Adminis-
trator shall authorize a State, which he determines
has the capability of administering a permit pro-
gram which will carry out the objectives of this
chapter to issue permits for discharges into the
navigable waters within the jurisdiction of such
State. The Administrator may exercise the authori-
ty granted him by the preceding sentence only
during the period which begins on October 18, 1972,
and ends either on the ninetieth day after the date
of the first promulgation of guidelines required by
section 1314(i)(2) of this title, or the date of approval
by the Administrator of a permit program for such
State under subsection (b) of this section, whichever
date first occurs, and no such authorization to a
State shall extend beyond the last day of such
period. Each such permit shall be subject to such
conditions as the Administrator determines are nec-
essary to carry out the provisions of this chapter.
No such permit shall issue if the Administrator
objects to such issuance.
(b) State permit programs
At any time after the promulgation of the guide-
lines required by subsection (i)(2) of section 1314 of
this title, the Governor of each State desiring to
administer its own permit program for discharges
into navigable waters within its jurisdiction may
submit to the Administrator a full and complete
description of the program it proposes to establish
and administer under State law or under an inter-
state compact. In addition, such State shall submit
a statement from the attorney general (or the attor-
ney for those State water pollution control agencies
which have independent legal counsel), or from the
chief legal officer in the case of an interstate agen-
cy, that the laws of such State, or the interstate
compact, as the case may be, provide adequate
authority to carry out the described program. The
Administrator shall approve each submitted pro-
gram unless he determines that adequate authority
does not exist:
(1) To issue permits which
(A) apply, and insure compliance with, any ap-
plicable requirements of sections 1311, 1312, 1316,
1317, and 1343 of this title;
(B) are for fixed terms not exceeding five
years; and
(C) can be terminated or modified for cause
including, but not limited to, the following:
(i) violation of any condition of the permit;
(ii) obtaining a permit by misrepresentation,
or failure to disclose fully all relevant facts;
(iii) change in any condition that requires
either a temporary or permanent reduction or
elimination of the permitted discharge;
(D) control the disposal of pollutants into
wells;
(2)(A) To issue permits which apply, and insure
compliance with, all applicable requirements of sec-
tion 1318 of this title; or
(B) To inspect, monitor, enter, and require reports
to at least the same extent as required in section
1318 of this title;
(3) To insure that the public, and any other State
the waters of which may be affected, receive notice
of each application for a permit and to provide an
opportunity for public hearing before a ruling on
each such application;
(4) To insure that the Administrator receives no-
tice of each application (including a copy thereof)
for a permit;
(5) To insure that any State (other than the
permitting State), whose waters may be affected by
the issuance of a permit may submit written recom-
mendations to the permitting State (and the Admin-
istrator) with respect to any permit application and,
if any part of such written recommendations are not
accepted by the permitting State, that the permit-
ting State will notify such affected State (and the
Administrator) in writing of its failure to so accept
such recommendations together with its reasons for
so doing;
(6) To insure that no permit will be issued if, in
the judgment of the Secretary of the Army acting
through the Chief of Engineers, after consultation
-------
Coast Guard is operating, anchorage and navigation
of any of the navigable waters would be substan-
tially impaired thereby;
(7) To abate violations of the permit or the permit
program, including civil and criminal penalties and
other ways and means of enforcement,*
(8) To insure that any permit for a discharge
from a publicly owned treatment works includes
conditions to require the identification in terms of
character and volume of pollutants of any signifi-
cant source introducing pollutants subject to pre-
treatment standards under section 1317(b) of this
title into such works and a program to assure
compliance with such pretreatment standards by
each such source, in addition to adequate notice to
the permitting agency of (A) new introductions into
such works of pollutants from any source which
would be a new source as defined in section 1316 of
this title if such source were discharging pollutants,
(B) new introductions of pollutants into such works
from a source which would be subject to section
1311 of this title if it were discharging such pollu-
tants, or (C) a substantial change in volume or
character of pollutants being introduced into such
works by a source introducing pollutants into such
works at the time of issuance of the permit Such
notice shall include information on the quality and
quantity of effluent to be introduced into such treat-
ment works and any anticipated impact of such
change in the quantity or quality of effluent to be
discharged from such publicly owned treatment
works; and
(9) To insure that any industrial user of any
publicly owned treatment works will comply with
sections 1284(b), 1317, and 1318 of this title.
(c) Suspension of Federal program upon submission of
State program; withdrawal of approval of State
program; return of State program to Administra-
tor
(1) Not later than ninety days after the date on
which a State has submitted a program (or revision
thereof) pursuant to subsection (b) of this section,
the Administrator shall suspend the issuance of
permits under subsection (a) of this section as to
those discharges subject to such program unless he
determines that the State permit program does not
meet the requirements of subsection (b) of this
section or does not conform to the guidelines issued
under section 1314(i)(2) of this title. If the Adminis-
trator so determines, he shall notify the State of
any revisions or modifications necessary to conform
to such requirements or guidelines.
(2) Any State permit program under this section
shall at all times be in accordance with this section
and guidelines promulgated pursuant to section
1314(iX2) of this title.
(3) Whenever the Administrator determines after
public hearing that a State is not administering a
program approved under this section in accordance
with requirements of this section, he shall so notify
the State and, if appropriate corrective action is not
taken within a reasonable time, not to exceed ninety
days, the Administrator shall withdraw approval of
such program. The Administrator shall not with-
draw approval of any such program unless he shall
first have notified the State, and made public, in
writing, the reasons for such withdrawal.
(4) Limitations on partial permit program returns
and withdrawals.
A State may return to the Administrator adminis-
tration, and the Administrator may withdraw under
paragraph (3) of this subsection approval, of
(A) a State partial permit program approved
under subsection (nX3) of this section only if
the entire permit program being administered
by the State department or agency at the time
is returned or withdrawn; and
(B) a State partial permit program approved
under subsection (n){4) of this section only if an
entire phased component of the permit program
being administered by the State at the time is
returned or withdrawn.
(d) Notification of Administrator
(1) Each State shall transmit to the Administrator
a copy of each permit application received by such
State and provide notice to the Administrator of
every action related to the consideration of such
permit application, including each permit proposed
to be issued by such State.
(2) No permit shall issue (A) if the Administrator
within ninety days of the date of his notification
under subsection (b)(5) of this section objects in
writing to the issuance of such permit, or (B) if the
Administrator within ninety days of the date of
transmittal of the proposed permit by the State
objects in writing to the issuance of such permit as
being outside the guidelines and requirements.of
this chapter. Whenever the Administrator objects
to the issuance of a permit under this paragraph
such written objection shall contain a statement of
the reasons for such objection and the effluent
limitations and conditions which such permit would
include if it were issued by the Administrator.
(3) The Administrator may, as to any permit
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(4) In any case where, after December 27, 1977,
the Administrator, pursuant to paragraph (2) of this
subsection, objects to the issuance of a permit, on
request of the State, a public hearing shall be held
by the Administrator on such objection. If the
State does not resubmit such permit revised to meet
such objection within 30 days after completion of
the hearing, or, if no hearing is requested within 90
days after the date of such objection, the Adminis-
trator may issue the permit pursuant to subsection
(a) of this section for such source in accordance with
the guidelines and requirements of this chapter.
(e) Waiver of notification requirement
In accordance with guidelines promulgated pursu-
ant to subsection (i)(2) of section 1314 of this title,
the Administrator is authorized to waive the re-
quirements of subsection (d) of this section at the
time he approves a program pursuant to subsection
(b) of this section for any category (including any
class, type, or size within such category) of point
sources within the State submitting such program.
(f) Point source categories
The Administrator shall promulgate regulations
establishing categories of point sources which he
determines shall not be subject to the requirements
of subsection (d) of this section in any State with a
program approved pursuant to subsection (b) of this
section. The Administrator may distinguish among
classes, types, and sizes within any category of
point sources.
(g) Other regulations for safe transportation, handling;,
carriage, storage, and stowage of pollutants
Any permit issued under this section for the dis-
charge of pollutants into the navigable waters from
a vessel or other floating craft shall be subject to
any applicable regulations promulgated by the Sec-
retary of the department in which the Coast Guard
is operating, establishing specifications for safe
transportation, handling, carriage, storage, and
stowage of pollutants.
(h) Violation of permit conditions; restriction or prohi-
bition upon introduction of pollutant by source
not previously utilizing treatment works
In the event any condition of a permit for dis-
charges from a treatment works (as defined in
section 1292 of this title) which is publicly owned is
violated, a State with a program approved under
subsection (b) of this section or the Administrator,
where no State program is approved or where the
Administrator determines pursuant to section
1319(a) of this title that a State with an approved
program has not commenced appropriate enforce-
ment action with respect to such permit, may pro-
ceed in a court of competent jurisdiction to restrict
or prohibit the introduction of any pollutant into
such treatment works by a source not utilizing such
treatment works prior to the finding that such
condition was violated.
(i) Federal enforcement not limited
Nothing in this section shall be construed to limit
the authority of the Administrator to take action
pursuant to section 1319 of this title.
(j) Public information
A copy of each permit application and each permit
issued under this section shall be available to the
public. Such permit application or permit, or por-
tion thereof, shall further be available on request
for the purpose of reproduction.
(k) Compliance with permits
Compliance with a permit issued pursuant to this
section shall be deemed compliance, for purposes of
sections 1319 and 1365 of this title, with sections
1311, 1312, 1316, 1317, and 1343 of this title, except
any standard imposed under section 1317 of this
title for a toxic pollutant injurious to human health.
Until December 31, 1974, in any case where a per-
mit for discharge has been applied for pursuant to
this section, but final administrative disposition of
such application has not been made, such discharge
shall not be a violation of (1) section 1311, 1316, or
1342 of this title, or (2) section 407 of this title,
unless the Administrator or other plaintiff proves
that final administrative disposition of such applica-
tion has not been made because of the failure of the
applicant to furnish information reasonably re-
quired or requested in order to process the applica-
tion. For the 180-day period beginning on October
18, 1972, in the case of any point source discharging
any pollutant or combination of pollutants immedi-
ately prior to such date which source is not subject
to section 407 of this title, the discharge by such
source shall not be a violation of this chapter if such
a source applies for a permit for discharge pursuant
to this section within such 180-day period.
(/) Limitation on permit requirement
(1) Agricultural return flows
The Administrator shall not require a permit
under this section for discharges composed entire-
ly of return flows from irrigated agriculture, nor
shall the Administrator directly or indirectly, re-
quire any State to require such a permit
(2) Stormwater runoff from oil, gas. and mining oper-
ations
The Administrator shall not require a permit
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directly or indirectly require any State to require
a permit, for discharges of stornuvater runoff
from mining operations or oil and gas exploration,
production, processing, or treatment operations or
transmission facilities, composed entirely of flows
which are from conveyances or systems of con-
veyances (including but not limited to pipes, con-
duits, ditches, and channels) used for collecting
and conveying precipitation runoff and which are
not contaminated by contact with, or do not come
into contact with, any overburden, raw material,
intermediate products, finished product, byprod-
uct, or waste products located on the site of such
operations.
(m) Additional pretreatment of conventional pollutants
not required
To the extent a treatment works (as defined in
section 1292 of this title) which is publicly owned is
not meeting the requirements of a permit issued
under this section for such treatment works as a
result of inadequate design or operation of such
treatment works, the Administrator, in issuing a
permit under this section, shall not require pretreat-
ment by a person introducing conventional pollu-
tants identified pursuant to section 1314(a)(4) of this
title into such treatment works other than pretreat-
ment required to assure compliance with pretreat-
ment standards under subsection (b)(8) of this sec-
tion and section 1317(b)(1) of this title. Nothing in
this subsection shall affect the Administrator's au-
thority under sections 1317 and 1319 of this title,
affect State and local authority under sections
1317(b)(4) and 1370 of this title, relieve such treat-
ment works of its obligations to meet requirements
established under this chapter, or otherwise pre-
clude such works from pursuing whatever feasible
options are available to meet its responsibility to
comply with its permit under this section.
(n) Partial permit program
(1) State submission
The Governor of a State may submit under
subsection (b) of this section a permit program for
a portion of the discharges into the navigable
waters in such State.
(Z) Minimum coverage
A partial permit program under this subsection
shall cover, at a minimum, administration of a
major category of the discharges into the naviga-
ble waters of the State or a major component of
the permit program required by subsection (b) of
this section.
(3) Approval of major category partial permit pro.
grams
The Administrator may approve a partial per-
mit program covering administration of a major
category of discharges under this subsection if
(A) such program represents a complete per-
mit program and covers all of the discharges
under the jurisdiction of a department or agen-
cy of the State; and
(B) the Administrator determines that the
partial program represents a significant and
identifiable part of the State program required
by subsection (b) of this section.
(4) Approval of m^jor component partial permit pro-
grams
The Administrator may approve under this sub-
section a partial and phased permit program cov-
ering administration of a major component (in-
cluding discharge categories) of a State permit
program required by subsection (b) of this section
if
(A) the Administrator determines that the
partial program represents a significant and
identifiable part of the State program required
by subsection (b) of this section; and
(B) the State submits, and the Administrator
approves, a plan for the State to assume admin-
istration by phases of the remainder of the
State program required by subsection (b) of this
section by a specified date not more than 5
years after submission of the partial program
under this subsection and agrees to make all
reasonable efforts to assume such administra-
tion by such date.
(o) Anti-backsliding
(1) General prohibition
In the case of effluent limitations established
on the basis of subsection (a)(1)(B) of this section,
a permit may not be renewed, reissued, or mod-
ified on the basis of effluent guidelines promul-
gated under section 1314(b) of this title subse-
quent to the original issuance of such permit, to
contain' effluent limitations which are less strin-
gent than the comparable effluent limitations in
the previous permit In the case of effluent
limitations established on the basis of section
1311(b)(1)(C) or section 1313(d) or (e) of this title,
a permit may not be renewed, reissued, or mod-
ified to contain effluent limitations which are less
stringent than the comparable effluent limitations
in the previous permit except in compliance with
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(2) Exceptions
A permit with respect to which paragraph (1)
applies may be renewed, reissued, or modified to
contain a less stringent effluent limitation applica-
ble to a pollutant if
(A) material and substantial alterations or
additions to the permitted facility occurred af-
ter permit issuance which justify the application
of a less stringent effluent limitation;
(B)(i) information is available which was not
available at the time of permit issuance (other
than revised regulations, guidance, or test
methods) and which would have justified the
application of a less stringent effluent limita-
tion at the time of permit issuance; or
(ii) the Administrator determines that techni-
cal mistakes or mistaken interpretations of law
were made in issuing the permit under subsec-
tion (aXIXB) of this section;
(C) a less stringent effluent limitation is nec-
essary because of events over which the permit-
tee has no control and for which there is no
reasonably available remedy;
(D) the permittee has received a permit mod-
ification under section 1311(c), 1311(g), 1311(h),
131 l(i), 131 l(k), 131 l(n), or 1326(a) of this title;
or
(E) the permittee has installed the treatment
facilities required to meet the effluent limita-
tions in the previous permit and has properly
operated and maintained the facilities but has
nevertheless been unable to achieve the previ-
ous effluent limitations, in which case the limi-
tations in the reviewed, reissued, or modified
permit may reflect the level of pollutant control
actually achieved (but shall not be less strin-
gent than required by effluent guidelines in
effect at the time of permit renewal, reis-
suance, or modification).
Subparagraph (B) shall not apply to any revised
waste load allocations or any alternative grounds
for translating water quality standards into ef-
fluent limitations, except where the cumulative
effect of such revised allocations results in a
decrease in the amount of pollutants discharged
into the concerned waters, and such revised allo-
cations are not the result of a discharger eliminat-
ing or substantially reducing its discharge of pol-
lutants due to complying with the requirements
of this chapter or for reasons otherwise unrelated
to water quality.
(3) Limitations
In no event may a permit with respect to which
paragraph (1) applies be renewed, reissued, or
modified to contain an effluent limitation which is
less stringent than required by effluent guide-
lines in effect at the time the permit is renewed,
reissued, or modified. In no event may such a
permit to discharge into waters be renewed, reis-
sued, or modified to contain a less stringent ef-
fluent limitation if the implementation of such
limitation would result in a violation of a water
quality standard under section 1313 of this title
applicable to such waters.
(p) Municipal and industrial stormwater discharges
(1) General rule
Prior to October 1, 1992, the Administrator or
the State (in the case of a permit program ap-
proved under this section) shall not require a
permit under this section for discharges composed
entirely of stormwater.
(2) Exceptions
Paragraph (1) shall not apply with respect to
the following stormwater discharges:
(A) A discharge with respect to which a per-
mit has been issued under this section before
February 4, 1987.
(B) A discharge associated with industrial
activity.
(C) A discharge from a municipal separate
storm sewer system serving a population of
250,000 or more.
(D) A discharge from a municipal separate
storm sewer system serving a population of
100,000 or more but less than 250,000.
(E) A discharge for which the Administrator
or the State, as the case may be, determines
that the stormwater discharge contributes to a
violation of a water quality standard or is a
significant contributor of pollutants to waters
of the United States.
(3) Permit requirements
(A) Industrial discharges
Permits for discharges associated with indus-
trial activity shall meet all applicable provisions
of this section and section 1311 of this title.
(B) Municipal discharge
Permits for discharges from municipal storm
sewers
(i) may be issued on a system- or jurisdic-
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(ii) shall include a requirement to effec-
tively prohibit non-stormwater discharges
into the storm sewers; and
(iii) shall require controls to reduce the
discharge of pollutants to the maximum ex-
tent practicable, including management prac-
tices, control techniques and system, design
and engineering methods, and such other pro-
visions as the Administrator or the State de-
termines appropriate for the control of such
pollutants.
(4) Permit application requirements
(A) Industrial and large municipal discharges
Not later than 2 years after February 4,
1987, the Administrator shall establish regula-
tions setting forth the permit application re-
quirements for stormwater discharges de-
scribed in paragraphs (2KB) and (2XC). Appli-
cations for permits for such discharges shall be
filed no later than 3 years after February 4,
1987. Not later than 4 years after February 4,
1987, the Administrator or the State, as the
case may be, shall issue or deny each such
permit Any such permit shall provide for com-
pliance as expeditiously as practicable, but in no
event later than 3 years after the date of is-
suance of such permit.
(B) Other municipal discharges
Not later than 4 years after February 4,
1987, the Administrator shall establish regula-
tions setting forth the permit application re-
quirements for stormwater discharges de-
scribed in paragraph (2XD). Applications for
permits for such discharges shall be filed no
later than 5 years after February 4, 1987. Not
later than 6 years after February 4, 1987, the
Administrator or the State, as the case may be,
shall issue or deny each such permit. Any such
permit shall provide for compliance as expedi-
tiously as practicable, but in no event later than
3 years after the date of issuance of such
permit.
(5) Studies
The Administrator, in consultation with the
States, shall conduct a study for the purposes
of
(A) identifying those stormwater discharges
or classes of stormwater discharges for which
permits are not required pursuant to para-
graphs (1) and (2) of this subsection;
(B) determining, to the maximum extent
practicable, the nature and extent of pollutants
in such discharges; and
(C) establishing procedures and methods to
control stormwater discharges to the extent
necessary to mitigate impacts on water quality.
Not later than October 1, 1988, the Administrator
shall submit to Congress a report on the results
of the study described in subparagraphs (A) and
(B). Not later than October 1, 1989, the Adminis-
trator shall submit to Congress a report on the
results of the study described in subparagraph
(C).
(6) Regulations
Not later than October 1, 1992, the Administra-
tor, in consultation with State and local officials,
shall issue regulations (based on the results of the
studies conducted under paragraph (5)) which des-
ignate stormwater discharges, other than those
discharges described in paragraph (2), to be regu-
lated to protect water quality and shall establish a
comprehensive program to regulate such desig-
nated sources. The program shall, at a minimum,
(A) establish priorities, (B) establish requirements
for State stormwater management programs, and
(C) establish expeditious deadlines. The program
may include performance standards, guidelines,
guidance, and management practices and treat-
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-------
ATTACHMENT L
-------
to plankton, fish, shellfish, wildlife, shorelines,
and beaches;
(B) the effect of disposal of pollutants on ma-
rine life including the transfer, concentration, and
dispersal of pollutants or their byproducts
through biological, physical, and chemical pro-
cesses; changes in marine ecosystem diversity,
productivity, and stability; and species and com-
munity population changes;
(C) the effect of disposal, of pollutants on esth-
etic, recreation, and economic values;
(D) the persistence and permanence of the ef-
fects of disposal of pollutants;
(E) the effect of the disposal of varying rates,
of particular volumes and concentrations of pollu-
tants;
(F) other possible locations and methods of
disposal or recycling of pollutants including land-
based alternatives; and
(G) the effect on alternate uses of the oceans,
such as mineral exploitation and scientific study.
(2) In any event where insufficient information
exists on any proposed discharge to make a reason-
able judgment on any of the guidelines established
pursuant to this subsection no permit shall be is-
sued under section 1342 of this title.
(June 30, 1948, c. 758, Title IV, ง 403, as added Oct 18,
1972, Pub.L. 92-500, ง 2, 86 Stat. 883.)
Cross References
Best management practices for industry, see section 1314 of this
title.
Determination of State's authority to issue permits for dredged or
fill material, see section 1344 of this title.
Field laboratory and research facilities, see section 1254 of this
title.
Modification of effluent limitation requirements for point sources,
see section 1311 of this title.
Permits for discharge of pollutants, see section 1342 of this title.
Planning process to assure compliance with this section, see sec-
tion 1288 of this title
ง 1344. Permits for dredged or fill materi-
al [FWPCA ง 404]
(a) Discharge into navigable waters at specified disposal
sites
The Secretary may issue permits, after notice and
opportunity for public hearings for the discharge of
dredged or fill material into the navigable waters at
specified disposal sites. Not later than the fifteenth
day after the date an applicant submits all the
information required to complete an application for
a permit under this subsection, the Secretary shall
publish the notice required by this subsection.
(b) Specification for disposal sites
Subject to subsection (c) of this section, each such
disposal site shall be specified for each such permit
by the Secretary (1) through the application of
guidelines developed by the Administrator, in con-
junction with the Secretary, which guidelines shall
be based upon criteria comparable to the criteria
applicable to the territorial seas, the contiguous
zone, and the ocean under section 1343(c) of this
title, and (2) in any case where such guidelines
under clause (1) alone would prohibit the specifica-
tion of a site, through the application additionally of
the economic impact of the site on navigation and
anchorage.
(e) Denial or restriction of use of defined areas as
disposal sites
The Administrator is authorized to prohibit the
specification (including the withdrawal of specifica-
tion) of any defined area as a disposal site, and he is
authorized to deny or restrict the use of any defined
area for specification (including the withdrawal of
specification) as a disposal site, whenever he deter-
mines, after notice and opportunity for public hear-
ings, that the discharge of such materials into such
area will have an unacceptable adverse effect on
municipal water supplies, shellfish beds and fishery
areas (including spawning and breeding areas), wild-
life, or recreational areas. Before making such
determination, the Administrator shall consult with
the Secretary. The Administrator shall set forth in
writing and make public his findings and his rea-
sons for making any determination under this sub-
section.
(d) "Secretary" defined
The term "Secretary" as used in this section
means the Secretary of the Army, acting through
the Chief of Engineers.
(e) General permits on State, regional, or nationwide
basis
(1) In carrying out his functions relating to the
discharge of dredged or fill material under this
section, the Secretary may, after notice and oppor-
tunity for public hearing, issue general permits on a
State, regional, or nationwide basis for any category
of activities involving discharges of dredged or fill
material if the Secretary determines that the activi-
ties in such category are similar in nature, will
cause only minimal adverse environmental effects
when performed separately, and will have only mini-
mal cumulative adverse effect on the environment.
Any general permit issued under this subsection
shall (A) be based on the guidelines described in
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requirements and standards which shall apply to
any activity authorized by such general permit
(2) No general permit issued under this subsec-
tion shall be for a period of more than five years
after the date of its issuance and such general
permit may be revoked or modified by the Secretary
if, after opportunity for public hearing, the Secre-
tary determines that the activities authorized by
such general permit have an adverse impact on the
environment or such activities are more appropriate-
ly authorized by individual permits.
(f) Non-prohibited discharge of dredged or fill material
(1) Except as provided in paragraph (2) of this
subsection, the discharge of dredged or fill materi-
al
(A) from normal fanning, silviculture, and
ranching activities such as plowing, seeding, culti-
vating, minor drainage, harvesting for the produc-
tion of food, fiber, and forest products, or upland
soil and water conservation practices;
(B) for the purpose of maintenance, including
emergency reconstruction of recently damaged
parts, of currently serviceable structures such as
dikes, dams, levees, groins, riprap, breakwaters,
causeways, and bridge abutments or approaches,
and transportation structures;
(C) for the purpose of construction or mainte-
nance of farm or stock ponds or irrigation ditches,
or the maintenance of drainage ditches;
(D) for the purpose of construction of tempo-
rary sedimentation basins on a construction site
which does not include placement of fill material
into the navigable waters;
(E) for the purpose of construction or mainte-
nance of farm roads or forest roads, or temporary
roads for moving mining equipment, where such
roads are constructed and maintained, in accord-
ance with best management practices, to assure
that flow and circulation patterns and chemical
and biological characteristics of the navigable wa-
ters are not impaired, that the reach of the navi-
gable waters is not reduced, and that any adverse
effect on the aquatic environment will be other-
wise minimized;
(F) resulting from any activity with respect to
which a State has an approved program under
section 1288(b)(4) of this title which meets the
requirements of subparagraphs (B) and (C) of
such section,
is not prohibited by or otherwise subject to regula-
tion under this section or section 1311(a) or 1342 of
this title (except for effluent standards or prohibi-
tions under section 1317 of this title).
(2) Any discharge of dredged or fill material into
the navigable waters incidental to any activity hav-
ing as its purpose bringing an area of the navigable
waters into a use to which it was not previously
subject, where the flow or circulation of navigable
waters may be impaired or the reach of such waters
be reduced, shall be required to have a permit under
this section.
(g) State administration
(1) The Governor of any State desiring to admin-
ister its own individual and general permit program
for the discharge of dredged or fill material into the
navigable waters (other than those waters which
are presently used, or are susceptible to use in their
natural condition or by reasonable improvement as
a means to transport interstate or foreign com-
merce shoreward to their ordinary high water mark,
including all waters which are subject to the ebb
and flow of the tide shoreward to their mean high
water mark, or mean higher high water mark on the
west coast, including wetlands adjacent thereto)
within its jurisdiction may submit to the Administra-
tor a full and complete description of the program it
proposes to establish and administer under State
law or under an interstate compact. In addition,
such State shall submit a statement from the attor-
ney general (or the attorney for those State agen-
cies which have independent legal counsel), or from
the chief legal officer in the case of an interstate
agency, that the laws of such State, or the inter-
state compact, as the case may be, provide adequate
authority to carry out the described program.
(2) Not later than the tenth day after the date of
the receipt of the program and statement submitted
by any State under paragraph (1) of this subsection,
the Administrator shall provide copies of such pro-
gram and statement to the Secretary and the Secre-
tary of the Interior, acting through the Director of
the United States Fish and Wildlife Service.
(3) Not later than the ninetieth day after the date
of the receipt by the Administrator of the program
and statement submitted by any State, under para-
graph (1) of this subsection, the Secretary and the
Secretary of the Interior, acting through the Di-
rector of the United States Fish and Wildlife Ser-
vice, shall submit any comments with respect to
such program and statement to the Administrator in
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(h) Determination of State's authority to issue permits
under State program; approval; notification;
transfers to State program
(1) Not later than the one-hundred-twentieth day
after the date of the receipt by the Administrator of
a program and statement submitted by any State
under paragraph (1) of this subsection, the Adminis-
trator shall determine, taking into account any com-
ments submitted by the Secretary and the Secretary
of the Interior, acting through the Director of the
United States Fish and Wildlife Service, pursuant to
subsection (g) of this section, whether such State
has the following authority with respect to the
issuance of permits pursuant to such program:
(A) To issue permits which
(i) apply, and assure compliance with, any
applicable requirements of this section, includ-
ing, but not limited to, the guidelines estab-
lished under subsection (b)(1) of this section,
and sections 1317 and 1343 of this title;
(ii) are for fixed terms not exceeding five
years; and
(iii) can be terminated or modified for cause
including, but not limited to, the following:
(I) violation of any condition of the permit;
(II) obtaining a permit by misrepresenta-
tion, or failure to disclose fully all relevant
facts;
(III) change in any condition that requires
either a temporary or permanent reduction or
elimination of the permitted discharge.
(B) To issue permits which apply, and assure
compliance with, all applicable requirements of
section 1318 of this title, or to inspect, monitor,
enter, and require reports to at least the same
extent as required in section 1318 of this title.
(C) To assure that the public, and any other
State the waters of which may be affected, re-
ceive notice of each application for a permit and
to provide an opportunity for public hearing be-
fore a ruling on each such application.
(D) To assure that the Administrator receives
notice of each application (including a copy there-
of) for a permit.
(E) To assure that any State (other than the
permitting State), whose waters may be affected
by the issuance of a permit may submit written
recommendations to the permitting State (and the
Administrator) with respect to any permit applica-
tion and, if any part of such written recommenda-
tions are not accepted by the permitting State,
that the permitting State will notify such affected
State (and the Administrator) in writing of its
failure to so accept such recommendations togeth-
er with its reasons for so doing.
(F) To assure that no permit will be issued if, in
the judgment of the Secretary, after consultation
with the Secretary of the department in which the
Coast Guard is operating, anchorage and naviga-
tion of any of the navigable waters would be
substantially impaired thereby.
(G) To abate violations of the permit or the
permit program, including civil and criminal pen-
alties and other ways and means of enforcement
(H) To assure continued coordination with Fed-
eral and Federal-State water-related planning and
review processes.
(2) If, with respect to a State program submitted
under subsection (g)(1) of this section, the Adminis-
trator determines that such State
(A) has the authority set forth in paragraph (1)
of this subsection, the Administrator shall ap-
prove the program and so notify (i) such State and
(ii) the Secretary, who upon subsequent notifica-
tion from such State that it is administering such
program, shall suspend the issuance of permits
under subsections (a) and (e) of this section for
activities with respect to which a permit may be
issued pursuant to such State program; or
(B) does not have the authority set forth in
paragraph (1) of this subsection, the Administra-
tor shall so notify such State, which notification
shall also describe the revisions or modifications
necessary so that such State may resubmit such
program for a determination by the Administrator
under this subsection.
(3) If the Administrator fails to make a determi-
nation with respect to any program submitted by a
State under subsection (g)(1) of this section within
one-hundred-twenty days after the date of the re-
ceipt of such program, such program shall be
deemed approved pursuant to paragraph (2)(A) of
this subsection and the Administrator shall so notify
such State and the Secretary who, upon subsequent
notification from such State that it is administering
such program, shall suspend the issuance of permits
under subsection (a) and (e) of this section for
activities with respect to which a permit may be
issued by such State.
(4) After the Secretary receives notification from
the Administrator under paragraph (2) or (3) of this
subsection that a State permit program has been
approved, the Secretary shall transfer any applica-
tions for permits pending before the Secretary for
-------
issued pursuant to such State program to such
State for appropriate action.
(5) Upon notification from a State with a permit
program approved under this subsection that such
State intends to administer and enforce the terms
and conditions of a general permit issued by the
Secretary under subsection (e) of this section with
respect to activities in such State to which such
general permit applies, the Secretary shall suspend
the administration and enforcement of such general
permit with respect to such activities.
(i) Withdrawal of approval
Whenever the Administrator determines after
public hearing that a State is not administering a
program approved under subsection (h)(2)(A) of this
section, in accordance with this section, including,
but not limited to, the guidelines established under
subsection (bXl) of this section, the Administrator
shall so notify the State, and, if appropriate correc-
tive action is not taken within a reasonable time, not
to exceed ninety days after the date of the receipt
of such notification, the Administrator shall (1) with-
draw approval of such program until the Adminis-
trator determines such corrective action has been
taken, and (2) notify the Secretary that the Secre-
tary shall resume the program for the issuance of
permits under subsections (a) and (e) of this section
for activities with respect to which the State was
issuing permits and that such authority of the Sec-
retary shall continue in effect until such time as the
Administrator makes the determination described in
clause (1) of this subsection and such State again
has an approved program.
(j) Copies of applications for State permits and proposed
general permits to be transmitted to Administrator
Each State which is administering a permit pro-
gram pursuant to this section shall transmit to the
Administrator (1) a copy of each permit application
received by such State and provide notice to the
Administrator of every action related to the consid-
eration of such permit application, including each
permit proposed to be issued by such State, and (2)
a copy of each proposed general permit which such
State intends to issue. Not later than the tenth day
after the date of the receipt of such permit applica-
tion or such proposed general permit, the Adminis-
trator shall provide copies of such permit applica-
tion or such proposed general permit to the Secre-
tary and the Secretary of the Interior, acting
through the Director of the United States Fish and
Wildlife Service. If the Administrator intends to
provide written comments to such State with re-
spect to such permit application or such proposed
general permit, he shall so notify such State not
later than the thirtieth day after the date of the
receipt of such application or such proposed general
permit and provide such written comments to such
State, after consideration of any comments made in
writing with respect to such application or such
proposed general permit by the Secretary and the
Secretary of the Interior, acting through the Di-
rector of the United States Fish and Wildlife Ser-
vice, not later than the ninetieth day after the date
of such receipt If such State is so notified by the
Administrator, it shall not issue the proposed permit
until after the receipt of such comments from the
Administrator, or after such ninetieth day, which-
ever first occurs. Such State shall not issue such
proposed permit after such ninetieth day if it has
received such written comments in which the Ad-
ministrator objects (A) to the issuance of such pro-
posed permit and such proposed permit is one that
has been submitted to the Administrator pursuant
to subsection (hXIXE) of this section, or (B) to the
issuance of such proposed permit as being outside
the requirements of this section, including, but not
limited to, the guidelines developed under subsec-
tion (b)(1) of this section unless it modifies such
proposed permit in accordance with such comments.
Whenever the Administrator objects to the issuance
of a permit under the preceding sentence such writ-
ten objection shall contain a statement of the rea-
sons for such objection and the conditions which
such permit would include if it were issued by the
Administrator. In any case where the Administra-
tor objects to the issuance of a permit, on request of
the State, a public hearing shall be held by the
Administrator on such objection. If the State does
not resubmit such permit revised to meet such
objection within 30 days after completion of the
hearing or, if no hearing is requested within 90 days
after the date of such objection, the Secretary may
issue the permit pursuant to subsection (a) or (e) of
this section, as the case may be, for such source in
accordance.with the guidelines and requirements of
this chapter.
(k) Waiver
In accordance with guidelines promulgated pursu-
ant to subsection (i)(2) of section 1314 of this title,
the Administrator is authorized to waive the re-
quirements of subsection (j) of this section at the
time of the approval of a program pursuant to
subsection (hX2XA) of this section for any category
(including any class, type, or size within such cate-
gory) of discharge within the State submitting such
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(/) Categories of discharges not subject to requirements
The Administrator shall promulgate regulations
establishing categories of discharges which he de-
termines shall not be subject to the requirements of
subsection (j) of this section in any State with a
program approved pursuant to subsection (h)(2)(A)
of this section. The Administrator may distinguish
among classes, types, and sizes within any category
of discharges.
(m) Comments on permit applications or proposed gen-
eral permits by Secretary of the Interior acting
through Director of United States Fish and Wild-
life Service
Not later than the ninetieth day after the date on
which the Secretary notifies the Secretary of the
Interior, acting through the Director of the United
States Pish and Wildlife Service that (1) an applica-
tion for a permit under subsection (a) of this section
has been received by the Secretary, or (2) the Secre-
tary proposes to issue a general permit under sub-
section (e) of this section, the Secretary of the
Interior, acting through the Director of the United
States Pish and Wildlife Service, shall submit any
comments with respect to such application or such
proposed general permit in writing to the Secretary.
(n) Enforcement authority not limited
Nothing in this section shall be construed to limit
the authority of the Administrator to take action
pursuant to section 1319 of this title.
(o) Public availability of permits and permit applica-
tions
A copy of each permit application and each permit
issued under this section shall be available to the
public. Such permit application or portion thereof,
shall further be available on request for the purpose
of reproduction.
(p) Compliance
Compliance with a permit issued pursuant to this
section, including any activity carried out pursuant
to a general permit issued under this section, shall
be deemed compliance, for purposes of sections
1319 and 1365 of this title, with sections 1311, 1317,
and 1343 of this title.
(q) Minimization of duplication, needless paperwork,
and delays in issuance; agreements
Not later than the one-hundred-eightieth day af-
ter December 27, 1977, the Secretary shall enter
into agreements with the Administrator, the Secre-
taries of the Departments of Agriculture, Com-
merce, Interior, and Transportation, and the heads
of other appropriate Federal agencies to minimize,
to the maximum extent practicable, duplication,
needless paperwork, and delays in the issuance of
permits under this section. Such agreements shall
be developed to assure that, to the maximum extent
practicable, a decision with respect to an application
for a permit under subsection (a) of this section will
be made not later than the ninetieth day after the
date the notice for such application is published
under subsection (a) of this section.
(r) Federal projects specifically authorized by Congress
The discharge of dredged or fill material as part
of the construction of a Federal project specifically
authorized by Congress, whether prior to or on or
after December 27, 1977, is not prohibited by or
otherwise subject to regulation under this section,
or a State program approved under this section, or
section 1311(a) or 1342 of this title (except for
effluent standards or prohibitions under section
1317 of this title), if information on the effects of
such discharge, including consideration of the guide-
lines developed under subsection (b)(1) of this sec-
tion, is included in an environmental impact state-
ment for such project pursuant to the National
Environmental Policy Act of 1969 [42 U.S.C.A.
ง 4321 et seq.] and such environmental impact
statement has been submitted to Congress before
the actual discharge of dredged or fill material in
connection with the construction of such project and
prior to either authorization of such project or an
appropriation of funds for such construction.
(s) Violation of permits
(1) Whenever on the basis of any information
available to him the Secretary finds that any person
is in violation of any condition or limitation set forth
in a permit issued by the Secretary under this
section, the Secretary shall issue an order requiring
such person to comply with such condition or limita-
tion, or the Secretary shall bring a civil action in
accordance with paragraph (3) of this subsection.
(2) A copy of any order issued under this subsec-
tion shall be sent immediately by the Secretary to
the State in which the violation occurs and other
affected States. Any order issued under this sub-
section shall be by personal service and shall state
with reasonable specificity the nature of the viola-
tion, specify a time for compliance, not to exceed
thirty days, which the Secretary determines is rea-
sonable, taking into account the seriousness of the
violation and any good faith efforts to comply with
applicable requirements. In any case in which an
order under this subsection is issued to a corpora-
tion, a copy of such order shall be Served on any
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(3) The Secretary is authorized to commence a
civil action for appropriate relief, including a perma-
nent or temporary injunction for any violation for
which he is authorized to issue a compliance order
under paragraph (1) of this subsection. Any action
under this paragraph may be brought in the district
court of the United States for the district in which
the defendant is located or resides or is doing busi-
ness, and such court shall have jurisdiction to re-
strain such violation and to require compliance. No-
tice of the commencement of such acton1 shall be
given immediately to the appropriate State.
(4) Any person who violates any condition or
limitation in a permit issued by the Secretary under
this section, and any person who violates any order
issued by the Secretary under paragraph (1) of this
subsection, shall be subject to a civil penalty not to
exceed $25,000 per day for each violation. In deter-
mining the amount of a civil penalty the court shall
consider the seriousness of the violation or viola-
tions, the economic benefit (if any) resulting from
the violation, any history of such violations, any
good-faith efforts to comply with the applicable
requirements, the economic impact of the penalty on
the violator, and such other matters as justice may
require.
(t) Navigable waters within State jurisdiction
Nothing in this section shall preclude or deny the
right of any State or interstate agency to control
the discharge of dredged or fill material in any
portion of the navigable waters within the jurisdic-
tion of such State, including any activity of any
Federal agency, and each such agency shall comply
with such State or interstate requirements both
substantive and procedural to control the discharge
of dredged or fill material to the same extent that
any person is subject to such requirements. This
section shall not be construed as affecting or im-
pairing the authority of the Secretary to maintain
navigation.
(June 30, 1948, c. 758, Tide IV, ง 404, as added Oct 18,
1972, Pub.L. 92-500, ง 2, 86 Stat 884, and amended Dec.
27, 1977, Pub.L. 95-217, ง 67(a). (b), 91 Stat 1600; Feb. 4,
1987, Pub.L. 100-4, Title III, ง 313(d), 101 Stat. 45.)
> So in original. Probably should read "action"
Cross References
Areawide waste treatment management, compliance with guide-
lines established under this section, see section 1288 of this
title.
Definition of "federally permitted release", see section 9601 of
Title 42, The Public Health and Welfare.
Enforcement of permit provisions, see section 1319 of this title
Grant to State for reasonable cost of administering an approved
program under this section, see section 1285 of this title.
Illegality of pollutant discharges except as in compliance with this
section, see section 1311 of this title.
Permits for discharge of pollutants, see section 1342 of this title.
Records and reports, see section 1318 of this title.
State management of permit program, see section 1254 of this title.
Code of Federal Regulations
Enforcement, supervision and inspection, see 33 CFR 326.1 et seq.
General regulatory policies, see 33 CFR 320.1 et seq.
Nationwide permits, see 33 CFR 330.1 et seq.
Permits for discharges of dredged or fill material into waters of
the United States, see 33 CFR 323.1 et seq.
Procedures applicable to dredged and fill material, see 40 CFR
230.1 et seq., 231.1 et seq.
Processing of Department of the Army permits, see 33 CFR 325.1
et seq.
Public hearings, see 33 CFR 327.1 et seq.
State program transfer regulations, see 40 CFR 233.1 et seq.
Library References
Health and Environment ซ=25.7(13).
CJ.S. Health and Environment ง 107 et seq.
Law Review Commentaries
Damming agricultural drainage: The effect of wetland preserva-
tion and federal regulation on agricultural drainage in Minnesota.
Mark J. Hanson, 13 Wm.Mitchell L.Rev. 135 (1987).
Navigating through the Wetlands Act Marsha Wolf and Lewis
Goldshore, 120 NJ.LJ. 645 (1987).
Regulation of batture pollution and ecology. Stan Millan, 33
Loyola (La.) LRev. 921 (1988).
Section 404 of the Clean Water Actpermits for placement of
solid filljudicial review. Peter L. Koff, Laurie Burt and Cather-
ine L. Farrell, 29 Ann.Surv.Mass.L. 354 (1982)
The Clean Water ActMore Section 404: The Supreme Court
gets its feet wet 65 Boston U.L.Rev. 995 (1985).
Wetlands and agricultural: Environmental regulation and the
limits of private property. Gerald Torres, 34 U.Kan.L.Rev. 539
(1986).
ง 1345. Disposal or use of sewage sludge
[FWPCA ง 405]
(a) Permit
Notwithstanding any other provision of this chap-
ter or of any other law, in any case where the
disposal of sewage sludge resulting from the opera-
tion of a treatment works as defined in section 1292
of this title (including the removal of in-place sew-
age sludge from one location and its deposit at
another location) would result in any pollutant from
such sewage sludge entering the navigable waters,
such disposal is prohibited except in accordance
with a permit issued by the Administrator under
section 1342 of this title.
(b) Issuance of permit; regulations
The Administrator shall issue regulations govern-
ing the issuance of permits for the disposal of
sewage sludge subject to subsection (a) of this
section and section 1342 of this title. Such regula-
tions shall require the application to such disposal
of each criterion, factor, procedure, and require-
ment applicable to a permit issued under section
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ATTACHMENT M
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EPA Report No. (?0oJk.-'K 1 /i ~i f
August, 1993
REPORT OF WORKSHOP ON
GEOSYNTHETTC CLAY LINERS
hy
David E. Daniel and B. Tom Boardman
University of Texas at Austin
Department of Civil Engineering
Austin, Texas 78712
Cooperative Agreement No. CR-815546-01-0
Project Officer
G. Kenneth Dotson
U.S. Environmental Protection Agency
Risk Reduction Engineering Laboratory
Cincinnati, Ohio 45268
RISK REDUCTION ENGINEERING LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
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DISCLAIMER
The information in the document has been funded wholly or in part by the United States
Environmental Protection Agency under assistance agreement number CR-815546-01-0. It has been subject
to the Agency's peer and administrative review and has been approved for publication as a U.S. EPA
document. Mention of trade names or commercial products does not constitute endorsement or
recommendation for use.
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FOREWORD
Today's rapidly developing and changing technologies and industrial products and practices
frequently carry with them the increased generation of materials that, if improperly dealt with, can
threaten both public health and the environment. The United States Environmental Protection Agency
is charged by Congress with protecting the Nation's land, air, and water resources. Under a mandate of
national environmental laws, the Agency strives to formulate and implement actions leading to a
compatible balance between human activities and the ability of natural systems to support and nurture
life. These laws direct the U.S. EPA to perform research to define our environmental problems, measure
the impacts, and search for solutions.
The Risk Reduction Engineering Laboratory is responsible for planning, implementing, and
managing research, development, and demonstration programs to provide an authoritative, defensible
engineering basis in support of the policies, programs, and regulations of the U.S. EPA with respect to
drinking water, wastewater, pesticides, toxic substances, solid and hazardous wastes, and Superfund-
related activities. This publication is one of the products of that research and provides a vital
communication link between the researcher and the user community.
This report documents the available information concerning manufactured materials that
might be utilized in liner and cover systems for landfills, impoundments, site remediation projects, and
secondary containment structures. The information compiled in this report was obtained from
literature, from information supplied by manufacturers, and from discussions at a 2-day workshop held
on June 7 and 8, 1992 in Cincinnati. This report will be useful to scientists, engineers, and regulatory staff
who are considering use of these types of materials.
E. Timothy Oppelt
Director
Risk Reduction Engineering Laboratory
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ABSTRACT
A workshop was held at the Risk Reduction Engineering Laboratory in Cincinnati, Ohio,
on June 9-10, 1992 to discuss geosynthetic clay liners (GCLs). The purpose of the workshop was
to present and discuss the most recent information available on the use of GCLs. This
information will be of use to EPA program and regional officials, state regulatory officials, permit
writers, and designers of waste disposal facilities.
Information about GCLs was first presented by manufacturers. Four commercial GCL
producers manufacture distinctly different products from a variety of materials. One common
feature, however, of all GCLs is a thin layer of bentonite clay. Two of the four manufacturers mix
an adhesive with the clay while the other two use no adhesive but instead needle punch two
geotextiles together with the bentonite sandwiched between the geotextiles. The manufacturers
focused their discussions on technical developments, recent research results, quality control, and
comparison of GCLs to compacted clay liners (CCLs).
Testing procedures were discussed next. A variety of conformance and performance
tests can be performed, but standard test methods are lacking. In addition, no consensus has
been reached on the types of tests that should be required or the appropriate frequency of testing.
Interpretation of test data is not always free of ambiguity due in part to a lack of standard testing
methods.
The performance of geomembrane/GCL composite liners was discussed at length. The
hydraulic contact between the clay and geomembrane was the focus. If a geotextile separates the
clay from the geomembrane (as is the case with most GCLs), and there is a defect in the
geomembrane, some lateral spreading of liquid will take place in the geotextile. Although some
equations are available to estimate the effect of the geotextile, more research is needed to quantify
geomembrane/GCL composite behavior more fully.
Owner/operators of waste disposal facilities described their experiences with GCLs.
Experience varies widely; some companies have used GCLs extensively while others have used
them rarely. Experience seems to have been good to date but concern was expressed about the
need for further refinement of construction quality assurance procedures and resolution of
several technical issues.
Recent research findings at the University of Texas and Drexel University's Geosynthetic
Research Institute were described. The response of GCLs to differential settlement, such as
would be experienced in cover systems placed over compressible waste, has been studied. Most
of the GCLs tested maintained low hydraulic conductivity even when subjected to large
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differential settlement. The hydration, swelling, and strength of the bentonite in GCLs varies
depending upon the fluid (water or leachate) being used. The need to test with the site-specific
liquid was apparent.
The issue of equivalency of a GCL to a CCL was discussed. A number of criteria might
be applied, but only a few seem truly rational. Steady-state water flux and solute flux are
obvious and clear criteria that should usually be part of an equivalency analysis. Other criteria
can be applied but most are much less meaningful in terms of addressing regulatory compliance.
Finally, regulatory acceptance of GCLs was discussed. Although numerous site-specific
approvals of GCLs have been given by regulatory agencies, no blanket approvals or disapprovals
were identified. The EPA's RCRA Subtitle D regulations prescribe a geomembrane/CCL for
unapproved states but in approved states allow for equivalent designs to be accepted by state
regulatory agencies.
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Table of Contents
Disclaimer i i
Foreword i i i
Abstract i v
List of Figures xi
List of Tables xiii
1. Introduction 1
2. Manufacturer's Information 3
2.1 Bentofixฎ 3
2.1.1 Benefits of Needle Punching 3
2.1.2 Non-Woven Geo textiles 4
2.1.3 Bentonite 4
2.1.4 Laboratory Measurement of Hydraulic Conductivity 5
2.1.5 Overlaps.... 5
2.1.6 Installation Procedures 5
2.1.7 Case Histories 6
2.1.8 Supplemental Information 6
2.2 Bentomatฎ 7
2.2.1 A Brief History of Waste Management Practices 7
2.2.2 The Potential Role of Geosynthetic Clay Liners in Landfills 8
2.23 Future Directions for Research and Discussion 8
2.2.3.1 Intimate Contact 8
2.23.2 Puncture Concerns 12
2.23.3 Construction Quality Assurance 12
2.23.4 Research Directives :...12
2.23.5 Test Standards 13
2.2.4 Conclusion 13
2.3 Claymaxฎ 13
23.1 Benefits of Using a GCL 14
23.2 Quality Management 16
233 Available Information on Claymaxฎ 16
2.4 Gundsealฎ 16
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2.4.1 Cundsealฎ Composite System 21
2.4.1.1 Hydraulic Conductivity 21
2.4.1.2 Overlapped Seams 21
2.4.1.3 Composite Action 22
2.4.1.4 Internal Shear Strength 22
2.4.1.5 Interfacial Friction Resistance 25
2.4.2 Gundsealฎ as a Single Liner System 25
2.4.2.1 Soil Suction 25
2.4.2.2 Hydraulic Conductivity 25
2.4.2.3 Internal Shear Strength 26
2.4.2.4 Seams 27
2.4.2.5 Geotextile Separator 27
2.4.3 Conclusion 28
3. Testing Procedures 29
3.1 Quality Assessment for Bentonite Sealants 29
3.1.1 Bentonite 29
3.1.2 Primary Test Methods 31
3.1.2.1 Permeameter Testing 31
3.1.2.2 Swell Tests 31
3.1.2.2.1 Free Swell Test 31
3.1.2.2.2 Modified Free Swell Index Test 32
3.1.2.2.3 Swelling Pressure Test 32
3.1.2.3 Plate Water Absorption (PWA) Test 33
3.1.2.4 Liquid Limit Test 33
3.1.3 Secondary Test Methods 34
3.13.1 Apparent Colloid Content Test 34
3.1 -3.2 X-Ray Diffraction (XRD) Mineralogical Analysis 34
3.1.3.3 Cation Exchange Capacity (CEC) 35
3.1.3.4 Specific Surface Area 35
3.1.3.5 Chemistry 35
3.1.4 Conclusion 35
3.2 Conformance Testing of Geosynthetic Clay Liners 36
3.2.1 Testing Options 37
3.2.1.1 Shear Strength 38
3.2.1.2 Tensile Properties 38
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3.2.1.3 Puncture Resistance 38
3.2.1.4 Biaxial Stresses 38
3.2.1.5 Freeze-Thaw and Desiccation 39
3.2.2 Suggested List of Conformance Tests for GCLs 39
3.2.2.1 Hydraulic Conductivity Testing 39
3.2.2.2 Shear Strength Testing 39
3.2.2.3 Tensile Property Testing 44
3.2.2.4 Biaxial Stress Testing 46
3.23 Testing Frequency 47
3.2.4 Conclusion 47
3.3 The Determination and Interpretation of Shear Strength 47
3.3.1 Test Conditions 48
3.3.1.1 Normal Stress 48
3.3.1.2 Hydration Conditions 48
3.3.1.3 Rate of Shear 49
3.3.1.4 Method of Failure 50
3.3.2 Conclusion 50
4. Intimate Hydraulic Contact with Geomembrane 51
4.1 Intimate Contact for GCL/Geomembrane Composite Liner Systems 51
4.1.1 In-Situ Behavior of a GCL 51
4.1.2 The Case for Geotextile Placement Within a Composite Liner 52
4.1.3 Evaluation of Potential Leakage Rates 52
4.1.4 Ongoing Research 53
4.2 Questions from the Audience 54
4.3 Final Comments 55
5. Owner/Operator Experiences and Concerns 56
5.1 Clarke Lundell, Representing Waste Management of North America, Inc 56
ฆ 5.2 Charles Rivette, Representing Browning-Ferris Industries (BFI) 56
5.3 Kurt Shaner, Representing Chambers Development Comany, Inc 58
5.4 John Workman, Representing Laidlaw Waste Systems 59
6. Recent Research 60
6.1 The Hydraulic Conductivity of Large Scale Intact, Overlapped, and Composite
Geosynthetic Clay Liners 60
6.2 The Effect of Differential Settlement on the Hydraulic Conductivity of Geosynthetic
Clay Liners 62
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6.3 Stability of Final Covers Placed on Slopes with Geosynthetic Gay Liners 68
6.4 The Hydration Behavior and Mid-Plane Shear Strength of Four Geosynthetic Clay
Liners 72
Equivalency 76
7.1 Equivalency 76
7.1.1 Potential Applications 76
7.1.2 Differences Between CCLs and GCLs 77
7.1.3 Criteria for Equivalency 79
7.1.4 Hydraulic Issues 79
7.1.4.1 Steady Flux of Water 79
7.1.4.2 Steady Solute Flux 82
7.1.4.3 Adsorption Capacity 85
7.1.4.4 Time to Initiate Discharge of Water from Base of Liner 87
7.1.4.5 Breakout Time for Solute 88
7.1.4.6 Production of Consolidation Water 88
7.1.5 Physical/Mechanical Issues 89
7.1.5.1 Freeze/Thaw Resistance 89
7.1.5.2 Wet/Dry Effects 89
7.15.3 Response to Total Settlement 90
7.1.5.4 Response to Differential/Settlement 90
7.1.5.5 Stability on Slopes 90
7.1.5.6 Vulnerability to Erosion 91
7.1.5.7 Bearing Capacity 91
7.1.6 Construction Issues 91
7.1.6.1 Puncture Resistance 91
7.1.6.2 Effect of Subgrade Condition 92
7.1.6.3 Ease of Placement or Construction 92
7.1.6.4 Speed of Construction 92
7.1.6.5 Availability of Materials 92
7.1.6.6 Weather Constraints 93
7.1.6.7 Quality Assurance Requirements 93
7.1.7 Summary of Equivalency Issues 93
7.2 Discussion 95
Technical Concerns 96
8.1 The Effect of Freezing on Saturated Sodium Bentonite 96
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8.2 The Flow of Bentonite out of a GCL on a Side Slope 96
8.3 Designing for Side Slopes 97
8.4 Possibility of Overlaps Pulling Apart Due to Wet/Dry Cycles 97
8.5 Steep Slopes 97
8.6 Long Term Physical Stability 98
8.7 Long Term Shear Strength 98
8.8 Biotic Instabilities 98
9. References and Publications Related to GCLs 99
10. Appendix: List of Attendees 102
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List of Figures
Figure Title Page No.
2.1 Needle Punched System of Bentofixฎ - 3
22 Potential Double Composite Liner System - 9
23 Potential Single Composite Liner System - - 9
2.4 US EPA Recommended Landfill Cover Design 15
25 Potential Landfill Cover Design Incorporating a GCI - 15
2.6 Qem Quality Management Program Summary 17
2.7 Composite Action Test with Overlying Defective Geomembrane - 23
2.8 Variations in Bentonite Water Content beneath a Defective Geomembrane 24
2.9 Water Content vs. Time for Samples of Gundsealฎ Placed Within Sands of
Varying Water Content - 26
3.1 Flexible-Wall Apparatus 40
3.2 Rigid-Wall Apparatus - - - - 41
33 Large Diameter Rigid-Wall Apparatus 42
3.4 Typical Direct Shear Friction Apparatus - 43
35 Geosynthetic/Geosynthetic Direct Shear Testing 43
3.6 Wide Width Tensile Test Schematic - - 44
3.7 Cross Section of a Horizontal Containment Box in a Confined Creep Test
Mode ... 45
. 3.8 Biaxial Test Apparatus Schematic 46
6.1 Cross Sectional View of Test Set Up 61
6.2 Cross Sectional View of Modified Test Set Up - - 63
6.3 Plan View of Tank and Deflatable Bladder - 63
6.4 Hydraulic Conductivity vs. Time for Intact Bentomatฎ Sample IHS-2-D 64
6.5 Hydraulic Conductivity vs. Deformation for Intact Bentomatฎ Sample
IHS-2-D - 64
6.6 Hydraulic Conductivity vs. Time for Overlapped Bentomatฎ Sample
OHS-2-C - - 65
6.7 Hydraulic Conductivity vs. Deformation for Overlapped Bentomatฎ
Sample OHS-2-C - - - - 65
6.8 Hydraulic Conductivity vs. Time for Intact Claymaxฎ Sample IHS-l-A 66
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6.9 Hydraulic Conductivity vs. Deformation for Intact Claymaxฎ Sample
IHS-l-A". - 66
6.10 Hydraulic Conductivity vs. Time for Overlapped Claymaxฎ Sample
OHS-l-F 67
6.11 Hydraulic Conductivity vs. Deformation for Overlapped Claymaxฎ
Sample OHS-l-F 67
6.12 Hydraulic Conductivity of Bentomatฎ after a Large Settlement Prior to
I lydldtlOn ...WWH.M I ฆ I.... 1 I I I.I....MHM.W W.... 6 9
6.13 Hydraulic Conductivity of Gundsealฎ after a Large Settlement Prior to
6.14 Typical Profile of Final Cover with Geosynthetic Qay Liners 70
6.15 Profile of the Slope Used for Computations - 70
6.16 Relationship between Maximum Interfacial Displacement and Minimum
Interfacial Friction Angle for a 3:1 Slope 71
6.17 Relationship between Tension in the Geogrid and the Minimum Interfacial
Friction Angle for a 3:1 Slope 71
6.18 Hydration of GCLs Using Different Liquids 73
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List of Tables
Table Title Paee No.
2.1 Measurement of Hydraulic Conductivity for GCLs 5
22 Summary of Triaxial Permeability Test Data on Bentomatฎ 10
23 Summary of Direct Shear Test Data on Bentomatฎ 11
2.4 Qaymaxฎ Mineral Performance Testing 18
2.5 Qaymaxฎ Backing Material Testing - - 18
2.6 Qaymaxฎ Inspection andTesting 18
2.7 Qaymaxฎ GCL Material Specifications - 19
2.8 Partial List of Qaymaxฎ Hydraulic Conductivity Testing Data 20
2.9 Partial List of Claymaxฎ Frictional Resistance Data 20
2.10 Permeability to Various Hydrocarbons as a Function of Initial Bentonite
Water Content - - 27
6.1 Direct Shear Test Results Summary 75
7.1 Differences Between GCLs and CCLs 78
72 Potential Equivalency Issues 80
73 Summary of Equivalency Assessment - 94
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CHAPTER 1
INTRODUCTION
On June 7-8, 1990, the United States Environmental Protection Agency
(EPA) held a workshop to discuss the use of alternative barriers in the design of
cover and/or liner systems. The focus of the workshop was on the potential use
of geosynthetic clay liners (GCLs) as an alternative barrier. Since that
introductory conference, a significant amount of information has been gathered
through research and field applications. For this reason, another workshop on
the use of GCLs was held on July 9-10, 1992 at the EPA's Risk Reduction
Engineering Laboratory in Cincinnati, Ohio.
The purpose of the second workshop was to present and discuss the most
recent research available on the use of GCLs. As the use of GCLs has expanded
dramatically over the last few years, it is important that EPA program and
regional officials, state regulatory officials, permit writers, and designers keep up
to date on the latest information available on the use of these products.
The information discussed at the workshop held on July 9-10, 1992 was as
follows:
1) Manufacturer's Information. A compilation of information available on
each of the major GCL products was presented by the manufacturing
sector. (Presented by representatives for Bentofixฎ, Bentomatฎ,
Claymaxฎ, and Gundsealฎ)
2) Testing Procedures. The use of different testing methods and procedures
to determine the physical properties of GCLs was discussed. (Presented
by Richard Brown, John Boschuk, and Robert Bachus)
3) Intimate Contact. The mechanisms of intimate hydraulic contact between
geomembranes and GCLs were discussed. (Presented by John Bove)
4) Owner/Operator Experiences. An overview of information on the field
application of GCLs was presented by owner/operators of landfills.
(Presented by representatives of Waste Management of North America,
Browning-Ferris Industries, Chambers Development, and Laidlaw)
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5) Recent Research. The most recent research carried out by Drexel
University and the University of Texas at Austin was discussed.
(Presented by Robert Koerner, David Daniel, Mark LaGatta, B. Tom
Boardman, and Hsin-Yu Shan)
6) Equivalency. The equivalency of a GCL to a compacted clay liner was
discussed. (Presented by David Daniel)
7) Technical and Regulatory Concerns. An open discussion was held on the
technical concerns of the use of GCLs. (Presented by David Daniel and
Robert Landreth)
The purpose of this report is to summarize the information presented at
the GCL workshop held on July 9-10,1992. This report does not represent the
full extent of the information available on geosynthetic clay liners. Readers are
directed to the summary of the GCL workshop held on June 7-8, 1990 for
additional information (EPA 600/2-91/002). Rather, this report augments the
proceedings from the first workshop.
Information on Bentofixฎ, Bentomatฎ, Claymaxฎ, and Gundsealฎ is
presented in Chapter 2. Testing Procedures are discussed in Chapter 3. Intimate
contact is discussed in Chapter 4. Owner/operator experiences are listed in
Chapter 5. Recent university research is discussed in Chapter 6. Equivalency
concerns are addressed in Chapter 7. Technical concerns are voiced in Chapter 8.
A list of references and published papers and reports on GCLs is included in
Chapter 9. A list of attendees is presented in the Appendix.
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CHAPTER 2
MANUFACTURER'S INFORMATION
At the present time, there are four major products available on the
geosynthetic clay liner (GCL) market. These four products are Bentofixฎ,
Bentomatฎ, Claymaxฎ, and Gundsealฎ. Each product has its own unique
properties.
The manufacturer of each product was asked to speak about technical
discoveries that had been made since the previous meeting. The information
presented in this chapter was provided by the manufacturer's speaker.
2.1 Bentofixฎ (By Georg Heerten, Naue-Fasertechniik GmbH
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A GCL bound by needle punched fibers is said to allow for the installation
on steep slopes (up to 1.5 : 1), by preventing sliding between the components of
the GCL, while also increasing the internal shear strength of the GCL as a whole.
2.1.2 Non-Woven Geotextiles
The manufacturer stresses the importance of the robustness of the
geotextiles incorporated into the GCL. To allow the GCL to be needle punched
together, at least one layer must be a non-woven geotextile. Both geotextile
components must pass filter criteria in order to prevent the migration of
bentonite out of the GCL. The upper layer non-woven geotextile must also be
.puncture resistant. For this reason, the top cover layer geotextile must have a
minimum mass/area of .25 kg/m2 and pass a German puncture test. However, a
.12 kg/m2 woven geotextile may also be used. The manufacturer has not had the
opportunity to measure the hydraulic conductivity of a deformed section of
Bentofixฎ after passing the puncture test. This is still being investigated.
To avoid lateral wicking in the upper non-woven geotextile, when a
geomembrane is placed on the GCL to form a composite liner, the pore space of
the upper geotextile is filled with powdered bentonite. The bentonite powder is
said to be fixed by a patented system which fills the non-woven pores. This
system is also said to improve the intimate contact between a GCL and an
overlying geomembrane by reducing the amount of loose powdered bentonite
dust where the two come in contact.
2.1.3 Bentonite
Bentofixฎ can be manufactured with powdered bentonite with 87% of the
mixture having a grain size less than 0.002 mm, or as a granular bentonite in the
size range of 0.5 to 4 mm. Due to its finer grain size, the powdered bentonite will
hydrate much quicker than a granular bentonite. Granular bentonite used to be
necessary when Bentofixฎ was used in conjunction with a geomembrane because
the powdered bentonite would create welding difficulties for the overlying
geomembrane. The manufacturer is said to have solved the problem of loose
powdered bentonite influencing the welding process of geomembranes by fixing
the bentonite to the geotextile, which addresses the intimate contact issue at the
same time.
-------
2.1.4 Laboratory Measurement of Hydraulic Conductivity
The manufacturer recommends that the procedures outlined in Table 2.1
be observed for the proper measurement of the hydraulic conductivity of a GCL.
Differences in GCL sample preparations can lead to large variations in the
measured value of hydraulic conductivity.
Table 2.1 Measurement of Hydraulic Conductivity for GCLs
Procedure
Important Steps
Possible Problems
Sampling
1) Exact Cutting (Stamping)
2) No bentonite loss on edges
3) Edge wetting
1) Flow around edge
2) Air encapsulation
Installation
1) Soaking filter plate
2) Applying flexible
membrane carefully
1) Air slows down
swelling
2) Loss of bentonite
Test Procedure
1) Proper saturation time
(50 hours minimum)
2) Cell pressure
(30 kPa minimum)
3) Hydraulic gradient
1) Inadequate water
Adsorption
Calculation
1) Measurement of
hvdrated sample thickness
1) Incorrect calculation
2.1.5 Overlaps
In the past, the overlapping seams had to be filled with loose powdered
bentonite or a hydrated bentonite paste. This will not be necessary in the future
due to the upper layer non-woven geotextile being filled with bentonite powder.
This system is said to provide a more intimate contact along the GCL overlap.
A prefabricated velcro system has also been designed to prevent
displacement along the overlaps due to movements during or after the covering
process.
2.1.6 Installation Procedures
Bentofixฎ will have the printing on the upper geotextile as well as an
overlap mark. Naue-Fasertechnik has also developed an installation manual
-------
which is delivered to each customer in advance. According to the manufacturer
a correct overlap can be achieved, and wicking in the non-woven plane can be
prevented, if the installation instructions are followed correctly.
2.1.7 Case Histories
1) Geomembrane Protection. In an effort to prevent the puncture of an
underlying geomembrane by the placement of a granular drainage material with
large particles (16 to 32 mm), Bentofixฎ has also been used as a cushion layer
over the geomembrane. The GCL not only protects the geomembrane, but
provides an additional seal, as well.
2) Vertical Gas Barrier. In an effort to prevent the seepage of landfill gas and
leachate, Bentofixฎ was placed in a vertical cutoff trench surrounding a landfill.
Apparently the soil moisture was sufficient to hydrate the bentonite resulting in a
sufficient gas barrier.
3) Sealing a Canal. In an effort to seal a canal and cofferdam, Bentofixฎ was
successfully installed in an underwater operation. The manufacturer states that
the needle punching allowed the GCL to withstand the immediate swelling and
the following installation procedure all while underwater.
4) Groundwater Protection System. In an effort to catch the run off from de-
icing impurities at the Munich II Airport, over 700,000 m2 of Bentofixฎ was
installed. The project has proved successful to date.
2.1.8 Supplemental Information
After the conference, Mr. Klaus Stief submitted additional information.
Because Bentofixฎ was developed in Germany, the manufacturer has followed
German and European regulations for landfills particularly closely. The
following is a summary of Mr. Stief s perspective on European policy on landfill
linings.
The Commission of the European Communities published in May 1992 a
proposed set of regulations for landfills. The proposal calls for liner systems,
leachate collection systems, and engineered cover systems. The lining system
may consist of natural, low-permeability soil, or lacking such soil, engineered
-------
liners must be used. There are no specific requirements for engineered liners; the
use of GCLs is in no way restricted.
Current German regulations are more stringent. The general liner
requirement in Germany is for a single composite liner consisting of a
geomembrane placed on 0.75 to 1.5 m of low-permeability compacted soil.
Similar requirements exist for the cap, although the soil liner component has a
smaller minimum thickness (0.5 m).
2.2 Bentomatฎ (By Robert Trauger, CETCO)
Bentomatฎ is manufactured by the Colloid Environmental Technology
Company (CETCO), which is a subsidiary of the American Colloid Company.
The representative from CETCO briefly discussed the results of recent
laboratory testing on Bentomatฎ, but mainly concentrated on the highlights and
advantages of the use of GCLs in the waste management industry.
2.2.1 A Brief History of Waste Management Practices
For several decades, the.only practical means of waste containment was
the construction of a hydraulic barrier consisting of a layer of compacted clay.
Unfortunately, the possibility of complete containment to the extent that a 1977
US EPA report on landfill liners suggested a "different approach," whereby
"pollution would be lessened by designing landfill liners for higher permeability
and by selectively attenuating the most toxic pollutants from the leachate..."
This novel idea of emphasizing attenuation over containment was never
implemented due to the emergence of geomembrane technology in the 1980's.
The near zero hydraulic conductivity of geomembranes made the concept of true
containment appear attainable. After a decade of technical progress,
geomembranes are now accepted by most designers as a required component of
landfill liners. The composite liner system, in which a geomembrane is placed
over a clay layer, was another fundamental advance as designers abandoned
attenuation considerations in favor of containment. Leakage rates through well
constructed composite liners are far lower than through geomembranes or
compacted clay liners (CCLs) alone. The only development missing in the shift
to containment oriented landfills was a series of federal regulations for landfill
liner design.
-------
The US EPA has just recently released the long awaited federal rules on
landfill design for municipal solid waste landfills. Unfortunately, GCLs were not
well established when the rules were drafted, so there is not yet a federal policy
on the role of GCLs in landfills.
2.2.2 The Potential Role of Geosvnthetic Clay Liners in Landfills
Some have suggested that GCLs are not merely a convenient substitute for
clay liners but instead represent the next step towards the goal of total waste
containment. GCLs have an extremely low, uniform hydraulic conductivity and
are not subject to the many materials and construction related problems that
commonly plague CCLs. Potential landfill liner cross sections reflecting this
design goal are shown in Fig. 2.2 and 2.3.
2.2.3 Future Directions for Research and Discussion
The GCL is an important innovation in lining technology, but its
performance can be undermined by poor design and installation. As with any
emerging technology, additional field and laboratory research is necessary to
strengthen the feedback loop for better designs, installations, and products.
Since the last GCL workshop held two years ago, a vast amount of useful data
has been obtained for Bentomatฎ. Some of the data are shown in Tables 2.2 and
2.3. More work needs to be done, however, to realize the full performance
capabilities of GCLs. Some of the most important remaining issues which the
technical, regulatory, and manufacturing communities must address are
discussed in succeeding subsections.
2.2.3.1 Intimate Contact
Concern has been expressed that the upper geotextile of a GCL could
prevent intimate contact between the geomembrane and the bentonite clay and
facilitate lateral movement along the interface. Overall leakage could
consequently increase because liquid is distributed over a broader area.
However, lateral movement may only occur at low confining stress, and the
quantification of the phenomenon is incomplete. When considering this issue
one must assess the theoretical advantages of geomembrane/CCL intimate
contact with respect to the many performance and installation advantages of a
geomembrane/GCL liner system.
-------
0.6 m Select Fill
Separator Geotextile
0.6 m Granular LCS
Cushioning Geotextile
Geomembrane
GCL
03 m Granular LDS
Geomembrane
GCL
0.6 m Structural Fill (or Clay)
SUBBASE
Figure 2.2 Potential Double Composite Liner System
Figure 2.3 Potential Single Composite Liner System
-------
Table 2.2 Summary of Triaxial Permeability Test Data on Bentomatฎ
TEST LAB DATE
PRODUCT MAX. EFFECTIVE HEAD(M>
CONF STRESSOCPA)
GRADIENT TOTAL permeability
TTME(HRS) 'CM/5EC1
J&L
07-05-90
SS
J&L
09-21-90
J&L 12-17-90
Geosyntec 12-20-90
J&L 01-08-91
A CC
J&L
D&M
05-02-91
07-05-91
07-15-91
Geosyntec 07-31-91
Nelson 09-04-91
A CC 06-18-91
CS
SS
CS
CS
CS
CS
SS
PL
PL
SS
SS
56.5
73
90.9
107
56.5
73
90.9
107
56.5
73
90.9
N/A
N/A
129
207
255
393
34
34
34
3
3.7
7J
11
3
3.7
7.3
11
3
3.7
7.3
9.1
4.6
11
11
2.7
16
2
3.7
7.0
30
380
760
1100
35
450
900
1315
30
400
800
2250
N/A
1800
200
530
217
160
360
840
26
6
13
4
62
19
46
2
36
28
7
25
72
25
216
4
190
720
1440
3600
2.1 x 10"9
7.5* 10'10
5.8 * 10"10
6.6 x 10"10
5.6 x 10"9
1.1 x 10"9
9.8 x 10"10
2.6 x 10"9
7.3 xlO-10"
7.3 x 10"10
1.4 x 10'9
1.4 x 10'9
2.0 x 10'9
1.6 x 10"9
3.6 x 10"9t
11 x 10"10
6.8 x 10*lฐtT
3.0 x 10"9*"
3.5 x 10"9*
3.0 x lO'9*
Notes:
J&L=J&L Testing Company, Inc.. Canonsburg. PA
Geosyntec = Geosyntec Consultants, Norcross. GA
D & M = Dames & Moore, Salt Lake City, UT
ACC = American Colloid Company, Arlington Heights, IL
Nelson = Robert L. Nelson & Associates, Schaumburg, IL
Permeant was landfill leachate
^ Permeant was salt water
ft Permeant was 600 ppm NaCN
^ Permeant was liquid fertilizer
-------
Table 2.3 Summary of Direct Shear Test Data on Bentomatฎ
lab" date interface*" normal moisture shear rate friction
STRESSESfKPA) CONDITION'' ANGLE (DEG1
J& L
05-30-90
NW/Sand
7/14/21
Hydrated
0-5 mm/min
35
NW/Sand
**
Dry
28
NW/Clay
Hydrated
**
41
NW/CIay
Dry
31
STS
09-11-90
NW/1 mmTexL HDPE
240/360/480
Dry
5 mm/min
18
NW/2 mm TexL HDPE
Dry
~
37
W/2 mm Text HDPE
"
Dry
24
J&L
11-06-90
NW/Sandy Soil
14/24/34
Dry
0 J mm/min
23
GRI
04-18-91
Internal
3/7/14/34/69/140/240
Dry
0.89 mm/min
42
0.83/3/7/34/.69
Hydrated
37
0.83/3/7/34/69
Hydrated^'
"
39
STS
05-28-91
NW/1 mmTexL HDPE
240/360/480
Hydrated
5 mm/min
20
W/2 mm TexL HDPE
Hydrated
19
UTA
08-12-91
Internal
41/62 / 96/130
Hydrated
0 J mm/min
26
J&L
09-09-91
W/Soil Cover
4/8.6/13.0
Hydrated
0.89 mm/min
22.5
W/Geonet
Hydrated
17
NW/2B Stone
Hydrated
53
TRI
05-06-92
W/1.5 mm Text. VLDPE
14/55/96
Hydrated
1 mm/min
22
W/1.5 mmSm. VLDPE
14/55/96
Hydrated
14
Notes:
* J & L = J & L Testing Company, Inc.. Canonsburg. PA (used a 75 mm Wykeham Farrance direct shear device)
STS = STS Consultants Lid-. North brook. IL (used a custom-made 300 mm shear box)
GRI = Geosynthetic Research Institute, Drexel University. Philadelphia. PA (used a Wykeham Fanance device)
UTA = University of Texas at Austin. Civil Engineering Laboratory (used a 60 mm direct shear box)
TRI = TRI Environmental Inc., Austin, TX (used a 300 mm direct shear box)
** NW = Non-woven geotextile of Bentomat
W = Woven geotextile of Bentomat
t "Dry" = sample tested in the as-received moisture state.
"Hydrated" = sample was hydra ted prior to testing, although the actual hydration methods vary.
Samples were hydrated with distilled water unless otherwise noted.
t't" Hydrated in leachaie.
-------
2.2.3.2 Puncture Concerns
There has been a great deal of concern over the potential for a GCL to be
more susceptible to puncture damage. This concern is often cited by regulators
as reason not to allow the use of GCLs. Liner systems in today's modem landfills
are more controlled than ever before and great care is usually taken to prevent
the possibility of puncture from above and below the liner. With GCLs, these
practices must be even more strongly emphasized, especially in the post
construction stage. The construction of a sound foundation and the placement of
cover material over the liner system must be rigidly controlled. If deemed
necessary, additional cover layers should be placed on the liner system to further
preclude the possibility of puncture. In other words, puncture prevention should
be emphasized during the construction process.
2.2.3.3 Construction Quality Assurance
GCLs can be easily and rapidly installed in comparison to geomembranes
and CCLs, yet a stringent construction quality assurance (CQA) plan must be
implemented. The best design and the most explicit project specifications mean
nothing if the installation is faulty. Comprehensive and realistic CQA programs
should be developed by GCL manufacturers and engineers. These programs
should detail installation criteria as well as materials conformance criteria. The
certification program under development by the National Institute for
Certification of Engineering Technologists (NICET) will be extremely valuable
for providing trained GCL installers, but more input is needed from installers
regarding methods of installation which minimize the potential for GCL damage.
2.2.3.4 Research Directives
The long term compatibility of a hydrated bentonite layer with the
variety of organic and inorganic chemicals it may encounter needs to be
investigated. Due to time constraints, these tests are inconvenient to run in a
controlled, repeatable fashion. New test methods may need to be developed to
provide meaningful data in a reasonable period of time. Results of this research,
however, could lead to improvements in contaminant resistant clays.
Direct shear testing is another area requiring additional research. There is
a seemingly limitless variety of soil and geosynthetic materials which may be
used in conjunction with a GCL. Each interface has its own unique frictional
-------
characteristics, and the designer needs a reliable evaluation of the applicable
friction angles to perform a slope stability analysis. A relatively sizable database
is already available, but more information is needed.
A long term, full scale field study of GCLs would also be informative. The
effects of freeze/thaw, desiccation, and settlement could all be observed on a
large scale.
2.2.3.5 Test Standards
The engineering and performance characteristics of GCLs are typically
evaluated using ASTM methods for soils and geosynthetics. For the geosynthetic
components of GCLs, these test methods are already acceptable or only require
minor modifications. Unfortunately there are no currently recognized standards
for preparing GCL test samples, for determining the quality of the bentonite
component, or for testing the entire product as a whole. At this time, all of the
major GCL manufacturers are working with ASTM to develop the necessary
standards.
2.Z4 Conclusion
The rapid increase in the use of GCLs over the past two years has made
intrepid pioneers out of manufacturers, regulators, and installers. Still, a
watchful eye must be maintained over the types of applications and designs in
which GCLs are specified. A poorly conceived design, or a careless installation,
can only serve to undermine the credibility that the industry has striven to
attain. In the coming years, everyone is urged to share his information and
experiences so that the state of the art can be advanced to the benefit of everyone
involved with geosynthetic clay liners.
2.3 Claymaxฎ (By Walter Grube, Jr., James Qem Corporation)
Claymaxฎ is manufactured by the Clem Environmental Corporation,
which is a branch of the James Clem Corporation. Claymaxฎ was the first GCL
product to be designed and introduced onto the market.
Claymaxฎ produces two products. The Claymaxฎ 200R is the original
product which consists of a layer of granular sodium bentonite sandwiched
between an upper primary woven geotextile and a lower secondary open weave
-------
geotextile. Other materials can be specified for the lower backing depending on
site specific needs. Claymaxฎ 200R is normally installed with the primary
geotextile on top, but this may be reversed depending on site-specific
requirements. Claymaxฎ 500SP has recently been introduced as a material with
high shear and tensile strength properties. The increase in strength has been
achieved by stitch-bonding the primary and secondary backing materials
together and by increasing the tensile strength of the backing materials
themselves.
2.3.1 Benefits of Using a GCL
The manufacturer discussed four reasons to use a GCL. These reasons are
discussed in more detail below.
1) Stop Seepage. In an effort to reduce seepage, a GCL can be used to fulfill the
low permeability requirement and as a design alternative to a compacted clay
liner. In order to attain this low permeability, the in place overlapping GCLs
must have seam integrity and the ability to successfully self heal.
2) Quality Control. The high degree of quality assurance/quality control
(QA/QC) in the materials and manufacture of the GCL make.it an attractive
alternative to compacted clay liners. The manufacturer also states that they will
provide field and technical support to ensure QA/QC. Also, the GCL customer
may perform independent conformance testing.
3) Standards of the Industry. Both the bentonite and geosynthetic industries
have a history of reliable standards and guidelines. The GCL manufacturers are
working with various standard-writing organizations in an effort to ensure a
high level of QA/QC.
4) Lack of Clay Reserves. Many regions do not have significant clay reserves.
As an example, the landfill cover design recommended by the US EPA, shown in
Fig. 2.4, is considered. As an alternative to a compacted clay liner, the
manufacturer recommends the landfill cover design shown in Fig. 2.5, which has
been modified to incorporate a GCL.
-------
vegctntion/aoil
top layer
drainage layer
low hydraulic conductivity
geomembrane/soil layer
\u M/ Wl. \l/
*S*SซS*NซS*SซS*SซS*%*S*SซSซS*S*\*\*Sซ
Vs.SซSซN.%%ซ%S.SปS.SซSซSปS.S.S.SซSป
60 cm
waste
filter layer
0.5 mm (20 mil)
geomembrane
Figure 2.4 US EPA Recommended Landfill Cover Design (EPA/625 / 4-91/025)
vegetation/soil
top layer
drainage layer
wi- \\l, a// Wl,
ii |i m r'ff* f i'iป iป
S*SปSซS*SซSซSซSซS*SซSปVSปSปVNซS,.S*
.S.S.S*S.\.ViS*S*SซS*\*S*S*NซS'S*NซS*
'S*S
-------
2.3.2 Quality Management
While data can be collected from small scale samples in the laboratory,
how will the product perform as a whole in the field? This is where construction
quality assurance for the GCL product becomes important.
The manufacturer states that the Clem quality management program is
independent of manufacturing, and follows all applicable and relevant standard
ASTM/API test methods. With each product sent to a client, a certification of
compliance is included detailing the properties of that particular shipment.
A summary of the quality management program undertaken at the James
Clem Corporation is shown in Fig. 2.6, and in Tables 2.4, 2.5, 2.6, and 2.7. Two
partial lists of available testing data are shown in Tables 2.8 and 2.9.
2.3.3 Available Information on Clavmaxฎ
The manufacturer states that the following information is available on the
Claymaxฎ product:
1) Case histories
2) Laboratory data
a) Compatibility studies
b) Shear resistance
c) Overlapped seam/damaged liner permeability tests
d) Freeze/thaw tests
3) Customer assistance
a) Engineers guide to GCL specifications
b) Engineers guide to GCL CQA programs
4) Design models and comparison studies
a) Slope stability analyses
b) Comparative flows (clay vs. Claymaxฎ)
c) Composite liner system comparative flow rates
d) Bentonite quantity calculations at seams
2.4 Gundsealฎ (By James Anderson, Gundle Lining Systems, Inc.)
Gundsealฎ is manufactured by Gundle Lining Systems, Inc. The
Gundsealฎ GCL consists of a layer of bentonite (5 kg/m2) adhered to a
geomembrane. Depending on the types of fluids that may come in contact with
-------
Fig. 2.6 Clem Quality Management Program Summary
-------
Table 2.4 Claymaxฎ Mineral Performance Testing
TEST
Performed?
AS DEUVERED
Criteria Frequency
AS REMOVED FROM FINISHED CLAYMAX
Performed? Criteria Freauencv
Gradation
X
per specs 8-10 per rail car
-
-
Moisture
Content
X
< 10%
X
25% ma*. 2000 m2 max.
pH
X
8-10.5
X
.
Plate
Water
Adsorption
X
860% min.
X
.
Free Swell
X
25 ml min.
X
27 ml min.
Fluid Loss
X
18 ml max.
X
12 ml max.
Table 2.5 Claymaxฎ Backing Material Testing
TEST SUPPLIER CLEM TESTED ACCEPTANCE CLEM TESTING
TESTED CRITERIA FREQUENCY
(MARV)
Grab Tensile Strength
X
X
400 N
7-10 per delivered
tiucidoad
Grab Tensile Elongation
X
X
15%
-
Puncture Strength
X
X
220 N
-
Mullin Burst
X
-
1700 kPa
-
Unit Weight
X
-
0.12 kg/m2
-
Wide Width Tensile
X
-
11 N/mm
-
Table 2.6 Claymaxฎ Inspection andTesting
TEST
MINIMUM TESTING
FREQUENCY
ACCEPTANCE CRITERIA
Bentonite Content
2000 m2
4.6 kg/m2 MARV
Composite Thickness
2000 m2
5.0 mm MARV
Bentonite Thickness
2000 m2
43 mm MARV
Permeability
70,000 m2
<5 x 10"' cm/sec@ 14 kPi
Overlapped Seam Permeability
(no granular bentonite)
70.000 m2
<5 x 10"'cm/sec@ 14 kPa
-------
Table 2.7 Claymaxฎ GCL Material Specifications
PROPERTY
TEST
METHOD
UNITS
CLAYMAX STYLE
200R
CLAYMAX STYLE
500SP
Sodium
Montmorillonite
Content
X-Ray
Diffraction
%
90 (typ)
90 (typ)
BENTONITE
PROPERTIES
*
Free Swell
Fluid Loss
USP-NF-XVQ
API 13 B
ML
ML
27 (MARV)
12 (Ma*. A.R.V.)
27 (MARV)
12 (Max. A.R.V.)
Moisture Content t
ASTM D4643
%
20 (tvo)
20 (tvp)
adhesive
Adhesion
Visual
Continuous Adhesion
to Backing Material
Continuous Adhesion
to Backine Material
Thickness (excluding
fabric)
ASTM D1777
MM
4.3 (MARV)
4J (MARV)
Composite Thickness
ASTM D1T77
MM
5 (MARV)
5 (MARV)
Wide Width Tensile
ASTM D4595
N/MM
11 (typ) tt
18 (typ)
PHYSICAL
PROPERTIES
Grab Tensile
Bentonite Content f
(a) 20% moisture
ASTM D4632
Weigh
12" X Roll Width
N
KG/M2
400 (MARV) tt
4.6 (MARV)
400 (MARV) tt
4.6 (MARV)
Shear Resistance
Hydrated
Drv
ASTM
D35.01.81.07
(draft)
DEC
DEG
>10
>35
>40
>40
Permeability
A) 14 kPa Effective Stress
ASTM D5084
CM/S
5 x 10-ป (Max. A.R.V.)
5 x 10"' (Max. A.R.V.)
B) 200 kPa Effective Stress
ASTM D5084
CM/S
< 5 x 10"10 (tvp)
< 5 x 10"10 (tvp)
Permeability
(14 kPa effective stress)
HYDRAULIC
PROPERTIES
C) 50 mm Overlapped
CTaymax (without the use
of granular bentonite
between the seams)
ASTM D5084
CM/S
< 5 x 10"' (typ)
< 5 x 10"' (typ)
0) Damaged Claymax
(3 each. 25 mm holes)
ASTM D5084
CM/S
< 5 x 10"' (typ)
N/At
C) Claymax underneath
damaged HDPE geo-
membrane (25 mm hole)
ASTM D5084
CM/S
< 5 x 10"' (typ)
N/A*
F) after 3 Wet/Dry Cycles
ASTM D5084
CM/S
< 5 x 10"' (typ)
N/At
G) after 5 Freeze/Thaw
Cycles
ASTMD5084
CM/S
<5 x 10"' (typ)
N/At
* Standard test methods modified where appropriate to facilitate testing a Geosynthetic Clay Liner (GCL).
* Properties of bentonite removed from finished GCL product,
t D4643 modified to included wet weight as the denominator,
tt Machine (warp) direction of primary backing,
t Testing in progress.
-------
Table 2.8 Partial List of Claymaxฎ Hydraulic Conductivity Testing Data
RANGE OF RESULTS
Standard
CLAYMAX 200R 2-1 x 10"9 cm//sec
CLAYMAX 500SP 2-4 x 10"9 cm/sec
25 mm hole prior to hydration* 3-5 x 10'9 cm/sec
50 mm overlapped seam* 3-5 x IP*9 an/sec
= self-healing tests on damaged liner and tests on overlapped seams were performed on both CLAYMAX 200R and
CLAYMAX 500SP.
Testing Parameters (ASTM D5084)
100-150 mm permeameter cells
5 kPa during hydration
14 kPa effective stress during consolidation
Table 2.9 Partial List of Claymaxฎ Frictional Resistance Data
INTERFACE
FRICTION ANGLE (')
ADHESION (KPA)
PBM: smooth HDPE
12
1
PBM: textured HDPE
22
1.9
SBM: smooth HDPE*
11
3
SBM: textured HDPE*
24
1.4
SBM: textured VLDPE
30
2.4
PBM: sand
29
0
PBM: #57 stone
31
1.6
INTERNAL
FRICTION ANGLE (')
COHESION (KPA)
CLAYMAX 200R
12
0.2
CLAYMAX 500SP
N/A
24
PBM = Primary Backing Material
SBM = Secondary Backing Material
= test done on CLAYMAX 500SP
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the GCL, the bentonite can either be a Wyoming sodium bentonite or a treated,
contaminant-resistant bentonite. The geomembrane can be either a HDPE or
VLDPE with a thickness ranging from 20 to 80 mils (0.5 to 2.0 mm). Textured
geomembranes can be used, as well.
Gundsealฎ can be installed in two ways. The first configuration is with
the geomembrane side facing downward against the subgrade, and with the
bentonite side facing upward against an overlying geomembrane, forming a
composite system. The second configuration is with the bentonite side facing
downward against the subgrade. Certain design criteria must be applied
depending on how the Gundsealฎ is to be installed.
2.4.1 Gundsealฎ Composite System
When Gundsealฎ is applied underneath a geomembrane with the
bentonite side facing upward, a composite liner system is formed. The success of
the composite system is a function of the hydraulic conductivity of the system,
the effectiveness of overlapped seams, the degree of intimate contact with
overlying geomembrane, the internal shear strength of the bentonite, and the
interfacial friction resistance between the components of the system.
2.4.1.1 Hydraulic Conductivity
The hydraulic conductivity of an intact specimen of Gundsealฎ has been
reported to be less than 4xl0"12 cm/s. Researchers at the University of Texas
(Daniel & Shan, 1992) and at GeoSyntec Consultants (1991) have reported that
the bentonite element of Gundsealฎ alone has a hydraulic conductivity between
lxlO*9 and lxlO"10 cm/s. Therefore, the 3 mm thick layer of bentonite, when
considered by itself, is equivalent to at least 300 mm of lxl0-7 cm/s clay. The
Gundsealฎ system, consisting of the geomembrane and the layer of bentonite, is
equivalent to well over 900 mm of lxlO"7 cm/s clay.
2.4.1.2 Overlapped Seams
When Gundsealฎ panels are overlapped, close contact is developed
between the bentonite portion of one panel and the geomembrane portion of the
other. Researchers at the University of Texas (Estornell, 1991) investigated the
effectiveness of this overlap by performing large scale tests on two separate
overlapping specimens. One sample had an overlap of 40 mm, while the other
-------
sample had an overlap of 75 mm. Two feet of gravel and one foot of water were
placed over each of the specimens. During the five-month-long test, no outflow
was noted through either of the overlapping specimens. Additional testing has
been performed by GeoSyntec Consultants (1991) and no flow was noted
through the overlapped seams after one hundred hours.
2.4.1.3 Composite Action
The effectiveness of the overlapped seams indicates that a good composite
action is formed between a geomembrane and the hydrated bentonite.
Additional research at the University of Texas (Estornell, 1991) has shown that
the bentonite portion of Gundsealฎ is able to seal off defects in an overlying
geomembrane. At the University of Texas, slits and holes were cut into a
geomembrane. This geomembrane was placed on top of the bentonite portion of
Gundsealฎ, and the system was covered with gravel and water. These tests were
performed for five months, during which time no flow was observed through the
system. After five months, the tests were dismantled and the condition of the
GCL was observed. Around the largest hole (75 mm diameter) in the
geomembrane, only a 130 mm diameter area was wetted on the bentonite, thus
indicating excellent intimate contact and composite action (Fig. 2.7).
The effectiveness of intimate contact between Gundsealฎ and an
overlying geomembrane was also investigated by the engineers at GeoSyntec
Consultants (1991). Their results indicated that the hydrated bentonite can
effectively seal a defect in an overlying geomembrane. Water contents were
taken from the bentonite portion of Gundsealฎ directly beneath a 1 mm diameter
hole. The water content tests indicated a significant reduction in the water
content of the bentonite radially away from the hole (Fig. 2.8).
2.4.1.4 Internal Shear Strength
The internal shear strength of the bentonite portion of Gundsealฎ has
been investigated by both the Geosynthetic Research Institute (1991) and the
University of Texas (Daniel and Shan, 1992). The internal friction angle for the
bentonite portion of Gundsealฎ in an unhydrated state (water content = 17%)
was found to range from 22ฐ to 26ฐ. The manufacturer states that due to the
effectiveness of composite action with an overlying geomembrane, the bentonite
portion of Gundsealฎ will remain basically unhydrated. Thus the internal
-------
Figure 2.7 Composite Action Test with Overlying Defective Geomembrane
(after Estomell, 1991)
-------
Initial Specimen Conditions: Water Content - 7.3%
Final Specimen Conditions: Wtter Contents:
- Section A - 77.2%
- Section B - 30.2%
- Section C - 24.0%
Figure 2.8 Variations in Bentonite Water Content beneath a Defective
Geomeirtbrane (after Geosyntec Consultants, 1991)
-------
friction angle of 22ฐ to 26ฐ can be used by designers if the bentonite remains
"dry."
2.4.1.5 Interfacial Friction Resistance
The interfacial friction angle between the smooth sheet geomembrane
portion of Gundsealฎ and the subgrade soil can be assumed to be approximately
16ฐ (Koerner, 1990). If a higher interfacial friction resistance is necessary, the
interfacial friction angle between a textured geomembrane portion of Gundsealฎ
and the subgrade soil can be assumed to range from 25ฐ to 32ฐ (Koerner, 1990).
The interfacial friction angle between the dry bentonite portion of
Gundsealฎ and the overlying geomembrane can be assumed to be 16ฐ for smooth
sheet (Koerner, 1990) and 32ฐ for a textured sheet (Westinghouse Inc., 1991).
2.4.2 Gundsealฎ as a Single Liner System
In some cases, engineers and designers desire to use Gundsealฎ as a
single liner system. This can occur in liner systems for reservoirs, disposal sites,
and at hydrocarbon storage tank facilities. The major factors affecting the
performance of Gundsealฎ in these areas are soil suction, hydraulic conductivity,
internal shear strength, and subgrade contamination.
2.4.2.1 Soil Suction
The University of Texas (Daniel and Shan, 1992) recently completed a
study on the effect of subgrade moisture content on the bentonite portion of
Gundsealฎ when the GCL was installed beneath a layer of medium grained sand
with the bentonite side of Gundsealฎ in contact with the sand. It was found that
the dry bentonite has a very high suction value of 7500 kPa and will draw
moisture from the sand. The amount of moisture "sucked up" by the bentonite
depends upon the moisture in the sand. Equilibrium can be reached between the
bentonite and the sand in a period varying from 2 to 14 days (Fig. 2.9).
2.4.2.2 Hydraulic Conductivity
If the bentonite side of Gundsealฎ is placed in contact with the subgrade
soil, the bentonite will hydrate. Depending on the initial water content on the
subgrade soil, the final water content of the bentonite can range from 50% to
over 145%.
-------
200
ฃ
o
c
2
c
ฃ
c
o
e
6
w
a
ฃ
10
20 30
Time (days)
40
50
Figure 2.9 Water Content vs. Time for Samples of Gundsealฎ Placed Within
Sands of Varying Water Content (Daniel & Shan, 1992)
The hydraulic conductivity of the bentonite portion of Gundsealฎ as a
function of the initial water content of the bentonite was recently studied at the
University of Texas (Daniel and Shan, 1992). Various hydrocarbons were used as
the permeant liquid in the study. The results are shown in Table 2.10.
2.4.2.3 Internal Shear Strength
The internal shear strength of the bentonite portion of Gundsealฎ has
been investigated by both the Geosynthetic Research Institute (1991) and the
University of Texas (Daniel and Shan, 1992). The internal friction angle for the
bentonite portion of Gundsealฎ in a hydrated (wet) state was found to 19ฐ at a
total normal stress less than 36 kPa, and 7ฐ at higher normal stresses. Therefore,
care must be taken to take into account the effect of normal stress when using a
friction angle in a stability analysis.
-------
Table 2.10 Permeability to Various Hydrocarbons as a Function of Initial
Bentonite Water Content (Daniel & Shan, 1992)
PERMEANT LIQUID
WQ = 17%
PERMEABILITY (CWS)
wq = 50% wq - 100% wq = 125%
WQ = 145%
Benzene
3 x 10*5
2 x 10"5
5 x 10*9
No Row
No Row
Gasoline
4 * 10"5
4 x I0"5
4 x 10*9
No Row
No Row
Methanol
3 * 10*5
3 x 10*5
3 x 10"9
No Row
No Row
MTBE
2 x 10"5
3 x 10*6
<1 x 10'9
No Row
No Row
TCE
4 x 10"3
4 x 10'5
3xl0"8
No Row
No Row
Water
2 x 10"9
-
-
-
-
2.4.2.4 Seams
When Gundsealฎ is installed with the bentonite side facing down, the
manufacturer recommends that tape be placed along the seam to prevent
overlying cover soils from separating the seams.
Alternatively, the overlapping geomembrane of the Gundsealฎ can be
heat seamed with fillet extrusion welding, or cap strip seams, to form a seamed
membrane composite barrier.
2.4.2.5 Geotextile Separator
When placed in contact with the subsoil, the bentonite portion of
Gundsealฎ will draw in moisture and become hydrated. While this reduces the
permeability to hydrocarbons, it also reduces the internal friction angle of the
bentonite. Therefore, in order to maintain the integrity of the bentonite and to
prevent contamination from the lower soils, it may be necessary, in cases of
nonuniform subgrades, to use a geotextile to maintain a separation between the
bentonite and the lower subgrade soils.
-------
2.4.3 Conclusion
Research has indicated that Gundsealฎ is an effective replacement for clay
in landfill liner systems and covers. Concern has been expressed, upon occasion,
by engineers, contractors, and regulators that the thin geosynthetic clay liners,
such as Gundsealฎ, are susceptible to damage during installation. However, the
installation of geosynthetic clay liners is much easier than the construction of
compacted clay liners, and when the contractors utilize the same care that is
needed to install a geomembrane, an effective liner or cover system is in place
and protecting the environment.
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CHAPTER 3
TESTING PROCEDURES
As GCLs are still relatively new to the market, the methods used to test
and to interpret these tests are still in their initial stages. Each of the major GCL
manufacturers is currently working to create standard methods of testing these
products. Until these standards are completed, it will be up to testing companies
and design engineers to decide how to set up and interpret the results of testing
on GCLs. The major problem is variable results arising from different testing
procedures.
Three speakers were given the opportunity to speak directly about testing
procedures. The first spoke about the number of different ways one can assess
the quality of the bentonite being used in the GCL product. The second spoke
about the number of laboratory tests one can perform in order to determine the
basic design parameters necessary to decide whether the product will perform as
anticipated. The third spoke specifically about how to determine and interpret
the shear strength of a GCL.
3.1 Quality Assessment for Bentonite Sealants (By Richard K. Brown,
WYO-BEN, Inc.)
The use of bentonite as an environmental sealant in the development of
low permeability horizontal barriers to fluid movement has become an accepted
and standard practice in landfill and lagoon construction for waste containment.
Despite this, and despite the fact that there are an abundance of methods
available for assessing quality in bentonite, there is as yet no standard practice or
accepted criteria for assessing the quality of the bentonite which is used in this
capacity. This paper presents a summary of those methods which may be used
for this purpose, along with a brief discussion of the suitability of each method
for this task.
3.1.1 Bentonite
Any discussion of test methods used to define bentonite quality would be
incomplete without a brief discussion of what bentonite is and how it works.
-------
Bentonite is a clay composed primarily of the crystalline, hydrous
alumino-silicate mineral montmorillonite. As a result, the unique
physicochemical characteristics of montmorillonite define the performance
capabilities of bentonite. Montmorillonite particles typically exist as minute,
very broad, extremely thin, three-layered crystals which have negative electrical
charges expressed on their surfaces. The presence of these charges causes
inorganic cations and polar molecules, such as water, to be attracted by and
absorbed to the montmorillonite crystal surfaces. There is strong evidence to
indicate that water which is absorbed by montmorillonite crystals becomes
bound in layers many molecules in thickness in a crystalline or quasi-crystalline
arrangement similar to that found in ice. The thickness of the bound water layer
is controlled by the negative electrical charge density on the montmorillonite
crystal surfaces. This is modified, however, by the effect of the particular
absorbed cations which are present, with sodium ions (Na+) enhancing the effect
while all other cations diminish it to varying degrees.
In dry bentonite, montmorillonite crystals tend to be arranged in a densely
packed surface to surface facing structure similar to the arrangement of cards in a
deck of cards. Water added to dry bentonite will be absorbed onto the crystal
surfaces causing adjacent crystals to move further apart. This expansion will
continue, as more water is added to the system up to the adsorption limits of the
montmorillonite. This process is the cause of the swelling phenomenon observed
when bentonites are wetted.
Studies have shown that the crystalline nature of the water absorbed by
montmorillonite crystals appears to cause it to be immobile or to act as a highly
viscous fluid, depending upon the hydraulic gradient under which it is placed. It
is this resistance to flow found in the absorbed water layer on montmorillonite
crystals which is the fundamental basis for the sealing capability exhibited by
bentonite.
As a result, those test methods which can be used to define the water
adsorption and swelling capability of bentonite should offer the best possibility
of indicating sealing capability. This statement holds true only for natural,
untreated bentonite or bentonite products, however. Many of the additives
which are commonly used to treat bentonite sealants mask this mechanism
making the definition of bentonite quality very difficult to accurately determine.
-------
3.1.2 Primary Test Methods
The methods presented here are those which, directly or indirectly, define
the sealing capability of bentonite and appear to offer the most promise, either
singularly or in combination, for defining quality in bentonite sealants.
3.1.2.1. Permeameter Testing
By far the best, most accurate and most direct way of assessing the quality
of a bentonite sealant would be to test its hydraulic conductivity under a
standard set of test conditions. Several bentonite manufacturing companies
have, in fact, established permeability performance tests specific for their own
products. Unfortunately, these tests often vary in their methods and conditions
making broad comparisons between products difficult. Although a standard test
method now exists to facilitate this type of testing (ASTM D 5084-90) there has, to
date, been no unified effort by any group to establish test conditions under which
such quality testing might be accomplished. Nevertheless, standard test
conditions for permeameter testing can be adopted by testing firms for project
specific comparison testing in order to determine relative quality of competing
bentonite Sealant products.
The absence of any standardized hydraulic conductivity test data for
bentonite sealant products, coupled with the high equipment cost for
permeameters and slowness in obtaining test results, has led to the use of a
number of other test methods which serve as indirect indicators of sealing
capability.
3.1.2.2 Swell Tests
Swell tests measure the ability of a bentonite to adsorb water by
measuring the increase in volume of a mass of bentonite which occurs during the
adsorption process. Several methods are available which allow measurement of
various aspects of the swelling characteristic.
3.1.2.2.1 Free Swell Test
This test method measures the swollen volume of a sample of powdered,
dried bentonite which has been added in numerous small increments over a
period of time to 100 ml of distilled water in a 100 ml graduated cylinder.
Measurement of bentonite volume is made from the gradations on the cylinder.
-------
Typically, this measurement is taken after the cylinder has set, undisturbed, for 2
to 24 hours following the final bentonite addition. In theory, this procedure gives
the test bentonite the opportunity to adsorb water and swell in an uninhibited
and unconfined fashion yielding a good representation of the swelling capacity
of the clay. This method is easily used, requires little equipment, and typically
has good reproducibility. Variations in the rate of bentonite addition, the
amount of bentonite added at each addition, and the setting time allowed can all
affect the result, however. Despite this, the results of this test method appear to
correlate well with the results of hydraulic conductivity testing. Although no
standard method currently exists for this test, one is now being developed by
ASTM.
3.1.2.2.2 Modified Free Swell Index Test
This test method, developed by Sivapullaiah et al. (1987) for clays
generally, measures the settled volume of clay sediment resulting from 3
additions of clay which have been mixed into a volume of water, typically 100
ml, in a graduated cylinder of suitable size, and then allowed to set, undisturbed,
for 24 hours. The sediment volume is measured using the graduations on the
cylinder. The resulting volume is then used to calculate the "Modified Free Swell
Index" of the clay using a formula which takes into account both the weight and
specific gravity of the solids used. This test is relatively simple to conduct and
appears to have good reproducibility for most bentonite materials. The
definition of sediment layer boundaries can be a problem when testing some
high quality natural sodium bentonites as well as with some treated bentonite
products, however. Reschke and Haug (1991) report that the results of this test
method show good correlation with the results of hydraulic conductivity testing
for compacted soil/bentonite mixtures (not pure bentonite).
3.1.2.2.3 Swelling Pressure Test
This test is included here because intuition suggests that swelling pressure
should inversely correlate strongly with hydraulic conductivity. No published
data have been found which establishes this correlation, however. Measurement
of the pressure exerted by hydrating bentonite as it adsorbs water and swells in a
confined space is typically done using consolidometers (Oscarson, et al., 1990).
-------
As a result, this test requires both sophisticated equipment and personnel in
order to properly conduct it. This may limit the wide spread use of this method.
3.1.2.3 Plate Water Absorption (PWA) Test
This test method measures the ability of a sample of powdered, dried
bentonite to "absorb" water when placed on a piece of filter paper on a porous
stone in a covered, water filled tray for 18 hours. The procedure for conducting
this test has been standardized as ASTM E 946. When properly conducted this
test is accurate to approximately + 5%, with test values for bentonites ranging
from 200 to 1100. The test is very sensitive to a number of conditions, such as
variations in the thickness of the bentonite sample on the filter paper, the number
of samples placed on each porous stone, the water level within the test tray, and
to even minor fluctuations in temperature during the period of the test. Failure
to adequately control these can result in swings in test results and very poor
reproducibility. As a result experienced personnel are required for this test in
order to obtain consistent results. Results from this test method appear to
correlate well with the results from hydraulic conductivity testing and with the
results of free swell testing. There appears to be very poor correlation between
PWA test results and modified free swell test results, however.
3.1.2.4 Liquid Limit Test
This test, as standardized in ASTM D 4318, sets forth a method for
determining the water content of a soil at the boundary between the soil's plastic
and liquid states. This method provides us another way to measure the water
adsorption capability of bentonite. Sivapullaiah et al. (1987) state that the liquid
limit, when expressed on a volume basis (volume of water to volume of soil),
shows a strong correlation with the modified free swell index test results.
Limited data presented by Reschke and Haug (1991) suggests a strong
correlation between liquid limit (as normally calculated) and both the modified
free swell index and hydraulic conductivity test results for high quality sodium
bentonites. These same data suggest little correlation for low quality sodium
bentonites. The simplicity of this test makes it a desirable one for use in
assessing sealing bentonite quality. However, additional testing is necessary to
establish the relationship between liquid limit and hydraulic conductivity.
-------
3.1.3 Secondary Test Methods
The methods described here are those which may be used in addition to
the primary test methods to further assist in defining quality in bentonite
sealants. These methods do not, by themselves, yield enough information to be
used as independent tests. As a result these tests should never be used as the
sole criterion in determining bentonite quality.
3.1.3.1 Apparent Colloid Content Test
This test method measures the fraction of a 2% water-dispersed sample of
bentonite that remains in suspension after an 18 to 24 hour settling period. In
theory, this test should be capable of measuring the montmorillonite content of a
bentonite sample because montmorillonite crystals should all be smaller than the
0.5 micron size threshold delimiting colloidal size particles which, by definition,
are small enough to stay permanently in aqueous suspension. Unfortunately,
factors such as incomplete sample dispersion, flocculation due to chemical
contaminants, and the effects of various additives all act to bias the test results.
In effect this test is simply a larger version of the Modified Free Swell Index Test
which was previously described, although different methods of analysis are used
in this method. When analyzed using the criteria of the Modified Free Swell
Index Test the results produced by the apparent Colloid Content Test do not
duplicate the results of the other test. Further, the Apparent Colloid Content Test
does not correlate strongly with the any of the primary tests, exhibiting only
moderate correlation with the Free Swell Test and the PWA Test.
3.1.3.2 X-Rav Diffraction (XRD) Mineralogical Analysis
X-Ray Diffraction analysis of a bentonite sample can be used to determine
its approximate mineralogical composition. However, because XRD is a semi-
quantitative method absolute percent compositions are not possible. Further,
while some inferences can be drawn from the results of this test as to the quality
of the montmorillonite crystals in a sample it is not possible to make any accurate
statements about sealing capabilities of the bentonite sample being tested based
solely on XRD results. At best, this method can be expected to provide only a
close approximation of the amount of montmorillonite present in a sample.
-------
3.1.3.3 Cation Exchange Capacity (CEO
The methods used to determine CEC measure the negative charge present
on the montmorillonite crystals in a bentonite. Although other, more accurate
methods are available, the CEC of bentonite is most often measured by
determining the ability of a sample to adsorb the positively charged- dye,
methylene blue. The Methylene Blue Dye Test has been standardized by the
American Petroleum Institute. The Methylene Blue Dye Test is capable of
yielding consistent, reproducible results when properly performed, although
these results are generally slightly lower than those produced by other CEC
determination methods.
3.1.3.4 Specific Surface Area
This test provides a measure of the montmorillonite crystal surface area
upon which water can potentially be adsorbed. Generally, higher surface area
values should be indicative of high quality bentonites having low hydraulic
conductivity. Limited data presented by Reschke and Haug (1991) show only
moderate correlation between surface area and hydraulic conductivity.
3.13.5 Chemistry
Definition of the gross chemical composition of bentonite, using X-Ray
Fluorescence or wet chemistry techniques, as well as definition of the
exchangeable cations present, using both wet chemistry and flame photometry,
can offer insights into bentonite quality. For example, Reschke and Haug (1991)
found that a strong correlation existed in the bentonites they tested between the
Si02Al2C>3 ratio and the quality of the material, while Alther (1986) found the
ratio of exchangeable sodium, calcium and magnesium had a significant effect on
the Theological and contamination resistance properties of bentonite. It must be
remembered, however, that the results of bentonite chemical analysis are only
useful when they are evaluated in the context of the results from other testing. A
wide variety of relationships between gross chemical and exchangeable cation
chemistries which would yield similar quality bentonites are no doubt possible.
3.1.4 Conclusion
Quality in bentonite sealants is specifically defined by the level of
impermeability or hydraulic conductivity achievable by a particular bentonite.
-------
Permeameter testing under a set of standard test conditions, therefore, offers the
most direct method of determining the quality of a bentonite sealant product.
Where this cannot be done, the water adsorption and swelling capabilities of a
bentonite, which are both fundamental characteristics of the sealing process, may
also be tested as indirect indicators of sealing effectiveness. A variety of test
methods may also be employed to define other bentonite characteristics such as
mineralogical composition, specific surface area, cation exchange capacity, and
others which, in combination with the results of water adsorption and/or
swelling tests, can serve to give a more complete picture of the quality of
bentonite sealants. However, additional test methods do not provide sufficient
information about the mechanism of the sealing process to enable them to be
used independently or as the principal method for determining bentonite sealant
quality.
3.2 Conformance Testing of Geosynthetic Clay Liners (By John Boschuk, Jr.,
J & L Engineering, Inc.)
As part of important construction activities using man-made or natural
materials, the engineer needs verification that specific materials for the project
conform to the design requirements and will perform as anticipated. Over the
past several years, a number of basic tests for each of the major geosynthetic
types have evolved and are included in specifications as conformance tests.
These tests are typically performed on material samples taken from the rolls as
they are manufactured or from the rolls on-site before the material is deployed.
Geosynthetic clay liners are increasingly being used in many projects and
may be considered relatively new to many engineers and regulators.
Conformance testing for these products is not yet well defined. The purpose of
this discussion is to suggest guidelines for testing methods and test frequencies
necessary to verify conformance of the materials with the design engineer's
requirements.
Unlike most other single-material-component geosynthetics, GCLs are a
combination of two or three different elements fused together to create a single
composite material. Two of the three elements consist of man-made
geosynthetics and the third is a processed natural material containing additives
-------
to bond the particles, assist in fusing the material to the geosynthetic or to
improve performance of the bentonite.
Considering the differences in the products, two basic choices exist for
conformance tests:
1) Test the individual elements of the composite.
2) Test the composite as a single material.
The first option is generally very difficult to exercise since the components
are bonded together. Separating the layers to perform tests on each material
component would probably damage the components and yield misleading test
results. Consequently, it is more logical to test the products as a composite.
Furthermore, the designer selected the material to function as a composite and
the design is based on the geosynthetic working as a composite.
3.2.1 Testing Options
As part of the research for this paper, the author queried the major users
of the material to determine what conformance tests they typically perform on
GCLs. Not surprising, testing has generally been limited to hydraulic
conductivity of the GCL, coupled with manufacturer's certifications. Often no
conformance testing is performed and verification is limited only to
manufacturer's certifications.
Further research indicates that no specific conformance, or even quality
control, testing of these products is typically specified other than hydraulic
conductivity. Verification is usually limited to visual inspections and visual field
checks to insure the material is not saturated until it is sealed and covered with a
confining load.
Before suggesting test protocols, an evaluation of the engineering
properties is warranted. First and foremost, the GCL products are being
marketed as a low permeability barrier. Consequently, hydraulic conductivity
and compatibility with the liquid to be retained should be emphasized.
However, there are several other important considerations, e.g., shear strength.
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3.2.1.1 Shear Streneth
As part of the design, the engineer may need to evaluate shear strength of
the composite and develop design properties for the material. Once production
of the material commences, verification of conformance to performance
characteristics would then be warranted.
3.2.1.2 Tensile Properties
For some designs the product may be subject to short term tensile stresses
such as during deployment. In this case the engineer would determine what
allowable tensile loads can be applied to the product without adversely affecting
other properties. Once these maximum allowable stresses are determined,
conformance testing would be specified to insure that the production materials
meet these standards.
In other instances, a design may require the product to be subjected to
unavoidable long term or residual stresses. If this is the case, long term creep
strains may occur and reduce its performance characteristics. Once the engineer
determines the maximum allowable sustained stress, criteria can be established
for design testing to verify material capabilities. Due to the duration of creep
testing, conformance testing is probably not warranted if the design carefully
considers these conditions.
3.2.1.3 Puncture Resistance
These products all have some puncture resistance capability. The
engineer's design testing program would evaluate how the material will perform
under the design conditions. Conformance testing is most likely not warranted
to verify this property. Competent field visual observations to insure that the
GCL is installed properly should suffice to insure performance.
3.2.1.4 Biaxial Stresses
Under certain conditions GCLs may be subject to differential settlements
such as in landfill cover systems. As part of the design, the engineer may
perform tests to assess performance and to establish design parameters. These
assessments may include biaxial stress tests followed by other engineering tests
on the stressed material. With these properties established, conformance testing
-------
under biaxial conditions may be warranted to verify material compliance with
critical design criteria.
3.2.1.5 Freeze-Thaw and Desiccation
GCLs contain bentonite which can be subjected to freeze-thaw and
desiccation that may affect performance. As part of the design process, these
conditions are evaluated and the design adjusted to accommodate these
concerns. Although conformance testing may be warranted under certain unique
conditions, bentonite supplied for these products is generally very uniform and
accompanied by supplier certifications and supplier QC testing. Research to date
also indicates that bentonite has unique healing properties after freeze-thaw and
desiccation. Proper design to accommodate freeze-thaw and desiccation,
coupled with supplier testing and certification documents, will most likely be
sufficient to insure satisfactory performance.
3.2.2 Suggested List of Conformance Tests for GCLs
Considering these design and performance elements a suggested list of
conformance tests is presented as a recommendation to design engineers:
3.2.2.1 Hydraulic Conductivity Testing
Two types of hydraulic conductivity tests are available: flexible-wall
permeameters (ASTM D5084) and rigid-wall permeameters. A schematic of each
is presented in Fig. 3.1 and 3.2. A modified large-scale rigid wall apparatus,
which is large enough to test seams in these products, is shown in Fig. 3.3. When
specifying these tests, it is recommended that the permeant be similar to the
liquids which will be exposed to the in-place material. Hydraulic gradients and
pressures should be specified by the engineer. Extreme care should be exercised
to insure the materia] is saturated and sealed at the sample edges.
3.2.2.2 Shear Strength Testing
Direct shear tests through the plane of bentonite can be performed on
either the standard 100 mm shear box or 305 mm shear box. J&L Engineering has
performed comparative tests with these products using both types of apparatus
and found the 100 mm shear box to be satisfactory for GCL materials. The
engineer should specify normal loads, rates of strain, liquid of saturation, fixity
-------
conditions, and preferred size of sample. Figures 3.4 and 3.5 present schematics
of the test configurations and fixity conditions.
Figure 3.1 Flexible-Wall Apparatus
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Pressure
Chamber
Line
Influent Line
Pressure
Chamber
Porous
Disks
Sand
Vent Line
Loading
Piston
% , *.; % ; % . .. \ . *..
ZSi*. -v.
Geosynihetic Qay
Liner (GCL)
64 mm Dia. Sample
Silicon Seal
E fTluent Line
Vent Line
Figure 3.2 Rigid-Wall Apparatus
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Pressure
Chamber
Line
Vent
Influent Line
Piston
Overlap
of GCL
^ 'jy/y/y/ysy/y/y.'y/yfyfyfyfy^yfy/y/y^yjysyjy/y.'y/y. x
v>. *./..*./..*. .*././.%*././././.ฆ/././.*."~ Cv
SX *. ; \ ; *. *. .~ \ , \ ; ; . ; . ; *. / ; *. ; ; . ; . ; *. , ; *. .~ \ ; *. ; \ ; \ V
^ i* ,i * - *. .*. *,.*.*~ /.*.*./.\\ฆ/././.'*. *. X
.** .*; .*; .*; .*; .*;
Witer under
Pressure to Apply
Confining Load
O-Ring Seals
Porous Didc
ฆGCL
Effluent Line
Figure 3.3 Large Diameter Rigid-Wall Apparatus
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(Fixed)
Normal Stress Loading Device
Normal Stress Indicator
Upper (FL*ed) Bo*
(300 mm * 300 mm min.)
Gamp
Direction of Travel
(Fixed)
Shear Force Indicator
Displacement Indicator
Lower (Travelling) Bo*
(300 mm * 300 mm min.) Bearings
Figure 3.4 Typical Direct Shear Friction Apparatus Schematic
FIXED/FIXED
Failure Constrained to
Geosynlheiic/Geo synthetic
Interface
FIXED/FREE
Failure along
S upestraie/Geosynthetic
Interface Prevented
FREE/FREE
Unconstrained Failure
Figure 3.5 Geosynthetic/Geosynthetic Direct Shear Testing
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3.2.2.3 Tensile Property Testing
For short term peak stress considerations, wide-width tensile testing per
ASTM D4595 is the most appropriate nationally recognized test procedure
available (Fig. 3.6). Care must be exercised to insure that the multiple composite
is properly clamped. The engineer may have to specify the grip type to insure
comparable results between the design and conformance tests, which may be
performed by different laboratories. As previously discussed, peak stresses may
develop during deployment of the GCL. Therefore, this testing would be
performed on the dry products.
Deflection
Gage
Load Cell
5200 mm.:
M
I
Sample
100 mm
\
Clamp (typ.)
Figure 3.6 Wide Width Tensile Test Schematic (Source: John Boschuk)
Creep testing is probably not warranted in that the design addresses this
issue and creep testing requires a long period of time to perform. If required to
insure compliance, the material should be saturated with the same type of liquid
the product will be exposed to in the field (Fig. 3.7).
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I
Load
Cell
Air
Supply
i
\
h
Epoxy/Resin
Reinforced
Gcotextile
Containment
Box
K>i
Y7777AV//////X/////S//////////A
I
1
/
Air
Supply
100 m
i
'////////////////////////A
Rubber
Rub-Sheet
Pressure
Bellows
ฆQ
Dead
Weight
Figure 3.7 Cross Section of a Horizontal Containment Box in a Confined Creep Test Mode
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3.2.2.4 Biaxial Stress Testing
Biaxial testing per GRI Test Method GM4 can be specified as a
conformance test to assess material bonding performance under conditions
similar to those in the field. The fluid used in the test should be similar to the
fluid the material will be exposed to in the field. The engineer should specify the
fluid, pressures, rate of pressure increase and allowable deflections (Fig. 3.8).
Pressure Deformation
Figure 3.8 Biaxial Test Apparatus Schematic (Source: John Boschuk)
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3.2.3 Testing Frequency
Typically, conformance tests are performed at a rate of one test series per
9000 m2 of product manufactured during a single run. If products are obtained
from a stockpile consisting of materials from different runs, testing frequencies
should be increased to insure that all runs are adequately tested. Recently, at
several projects of which Mr. Boschuk is aware, the testing frequency has been
increased to one test series per 4600 m2 of product. The engineer may have to
negotiate this frequency with regulatory authorities.
3.2.4 Conclusion
GCLs are relatively new to the industry and conformance tests are still
evolving. This presentation attempts to present technical considerations to
establish a conformance test program for GCLs which focuses on verification of
the designed performance properties of the product for its specific application.
Testing frequencies have also been suggested based on the testing frequencies
used for other geosynthetic materials.
It is important to note that these products are still evolving.
Manufacturers may be adjusting and changing the geosynthetics used in their
products, adjusting the methods of bonding the materials and even the types and
distribution of the bentonite used in the products. It is important that whatever
product is evaluated in the design be the same product used in the field.
Specifications need to address this issue and the manufacturer should be
consulted to insure the product tested in the design is the same product used
during construction.
3.3 The Determination and Interpretation of Shear Strength (By Robert
Bachus, GeoSyntec Consultants)
The topic of shear strength is familiar to anyone associated with
geoenvironmental engineering. With the development of geosynthetic clay liners
(GCLs), engineers are now faced with the task of evaluating the ability of GCLs
to transmit shear at an interface, or through the liner system. The solution to this
is to simulate expected field conditions in the laboratory in an attempt to model
and test the expected mode of shearing failure. The problem is that the "shear
strength" of the GCL is actually composed of three distinct components (interned
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shear strength, interfacial frictional resistance, and tensile strength). This
breakdown into the different components of shear strength coupled with the fact
that lab and/or field conditions greatly influence their value, makes the
fundamentals of shear strength much more complex than most people realize.
3.3.1 Test Conditions
The shear strength of a GCL must be determined under conditions
matching those anticipated in the field. When incorporating a friction angle into
a slope stability analysis one cannot expect any degree of accuracy if that friction
angle was determined under conditions varying widely from those in the field
analysis. The variation in normal stresses, degree and type of fluid hydration,
rate of shear, and method of failure are all important variables that a designing
engineer must consider.
3.3.1.1 Normal Stress
Over a small range of normal stresses there may appear to be a linear
relationship between normal stress and shear stress at failure (Mohr-Coulomb
failure envelope), but if taken over a broader range of normal stresses, this
relationship may not be linear. Therefore, the shear strength parameters of angle
of internal friction (') and cohesion (cO are not constant and depend upon the
range of normal stresses over which they are determined. Unfortunately, friction
angles and cohesion values are often published without any reference to the
normal stress at which they were determined. One must remember that ' and
d are not inherent properties of a GCL, but rather a convenient way of
representing the shear and normal stresses acting along a plane at the time of
failure.
3.3.1.2 Hydration Conditions
In addition to the type of fluid and the length of time for hydration, the
method used to hydrate the GCL can affect the measured internal shear strength.
For example, prior to direct shear testing, a GCL sample can be hydrated under a
normal load in or out of the shear box. Due to sample disturbance caused by
unloading and reloading, the sample hydrated outside the shear box will have a
different shear strength than the undisturbed sample hydrated within the shear
box.
-------
Another concept to consider is when should a hydrated GCL be
considered saturated? The bentonite within a GCL is generally a non-
homogeneous mixture of individual nodules. These nodules will tend to adsorb
any free water. Thus, at what water content will adsorption cease, and the
sample be considered saturated?
3.3.1.3 Rate of Shear
One of the testing variables most often overlooked is the rate at which the
sample is sheared. The slower a hydrated sample is sheared, the more time
excess pore water pressures have to dissipate. Thus the shear strength of a
saturated GCL is directly related to how quickly the sample is sheared.
This is why geoenvironmental engineers specify whether the shear
strength parameters O' and c' are for drained or undrained conditions. If a
hydrated sample is loaded slowly enough that excess pore water pressures have
time to dissipate, then the test is considered drained. If an engineer performs a
long term slope stability analysis (i.e. drained conditions), he must test a
representative sample under drained conditions as well. Due to the low
hydraulic conductivity of sodium bentonite, a direct shear test cannot be carried
out in a day on a GCL. Using the methods proposed by Gibson and Henkel
(1954), the time to failure can be estimated for very soft clays as tfaiiure = 50tso,
where tso is the time required to achieve 50% consolidation under the normal
stress being used. Using a constant shear rate of 0.02 mm/hr (1.31xl0~5 in/min),
researchers at the University of Texas (Daniel & Shan, 1991) found that the peak
shear stress was typically reached after 5 to 20 days of shearing for GCLs
incorporating sodium bentonite. Only two samples failed in less than five days.
Based on previous consolidation tests, the calculated minimum time to failure
was approximately 3 days. Thus, for these tests, the rate of shearing was slow
enough to ensure full dissipation of excess pore water pressure at the time of
failure.
Hydrated sodium bentonite clays have also been known to be susceptible
to creep. What effect does the long term sustained transmission of shear loads
have on the shear strength of a hydrated GCL? This question requires further
study.
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3.3.1.4 Method of Failure
The type of testing equipment can predetermine the mode of failure of a
GCL. A direct shear test would be used to determine the internal shear strength
of a GCL, while an inclined tilt table would be used to measure interfacial friction
resistance. Finding the tensile or internal shear strength of a stitch bonded or
needle punched GCL can be more difficult due to localized stress concentrations
caused by the stitching. Direct shear tests have been modified in order to force
the failure plane through the stitch or needle punch bonding.
3.3.2 Conclusion
While a lot of time and money can be put into measuring the shear
strength of GCLs, this information will not be very effective if it is not interpreted
correctly. One must remember that there is a non-linear relationship between
normal stress and shear stress at failure (curved failure envelope). Not only are
O7 and c! affected by normal stress, but also by the degree and fluid of hydration.
The testing conditions must always be specified when determining the shear
strength of a GCL. These testing conditions not only should match anticipated
field conditions, but should also be listed with the final results in order that
others may understand how to interpret the results.
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CHAPTER 4
INTIMATE HYDRAULIC CONTACT WITH GEOMEMBRANE
4.1 Intimate Contact for GCL/Geomembrane Composite Liner Systems (By
John Bove, Hazen and Sawyer, P.C)
The concept of "intimate contact" within composite liner systems for
waste disposal and storage facilities is not a new one. The intimate contact
approach is intended to minimize the lateral migration of fluid that may pass
through defects in the geomembrane, which is typically the upper component of
the composite liner. This concept enhances the contribution of the soil liner
component of the composite system in minimizing leakage through the liner and
discourages the use of a geotextile directly beneath the geomembrane.
Empirical and theoretical analyses of composite liner performance
persuasively highlight the advantages of intimate contact. Analyses indicate that
the presence of a high transmissivity drainage medium directly below the
geomembrane may increase the leakage rate through the liner by several orders
of magnitude compared with a composite system with good contact between the
components.
4.1.1 In-Situ Behavior of a GCL
Depending on the in situ conditions, the GCL may exhibit behavior
similar to anything ranging from a thin geotextile to a compacted soil liner in
good contact with the geomembrane. When considering the use of a GCL as a
substitute for the compacted soil component, it is important to understand the
mechanisms that may interrupt the ability to attain "intimate contact." Possible
mechanisms include:
Excessive transmissivity within the upper GCL geotextile (e. g., an
excessively thick upper geotextile)
Gaps, cracks, or breaks in GCL or at GCL panel ends
Imperfections in overlapped GCL seams
Localized wrinkles in GCL and/or geomembrane
-------
Uneven GCL subgrade surface
If a designer, owner/operator, or regulator believes that the presence of
the mechanisms listed above, or any others not listed, will prevent "intimate
contact," the use of GCLs in place of soil may be restricted. This provides a
challenge to the producers and users of GCLs.
4.1.2 The Case For Geotextile Placement Within a Composite Liner
The use of a thin geotextile between the soil and geomembrane
components of the soil liner system, while providing a drainage pathway, can
only transmit a finite quantity of fluid that has passed through a geomembrane
defect. This quantity is one or two orders of magnitude less than the upper
bound theoretical volume predicted by research conducted by the EPA
(assuming that the quantity of leachate at a given hydraulic head is always
available at the defect location). For thinner geotextiles with relatively low
hydraulic transmissivity, the volume of fluid that can be laterally transmitted
may be smaller than the quantity of fluid potentially generated by consolidating
soils or the dehydration of a GCL.
Even though a quantity of fluid can be transmitted laterally, it must still
pass through the bentonite component of a GCL before it can be considered as
leakage through the composite liner: For an intact GCL having a hydraulic
conductivity in the range of lxlO"9 to lxlO"10cm/s, this is a difficult task. In
reality though, the flow through the system is most likely to be controlled by the
apparent hydraulic conductivity and transmissivity of GCL seams and defects,
rather than the upper layer geotextile alone.
In an effort to increase slope stability, a separate geotextile placed between
the geomembrane and the underlying soil liner may actually allow for the
dissipation of excess pore water pressures. Thus, an increase in the internal shear
strength is realized at the expense of an increase in lateral flow.
4.1.3 Evaluation of Potential Leakage Rates
A significant step in understanding the future role of GCLs in composite
liner systems would be to define "intimate contact" in terms that may be
measured in the laboratory or the field. Clearly a composite system can allow
"some" volume of lateral drainage and still function as intended. The Action
Leakage Rate (ALR) quantity of 187 L/hectare/day often used for double lined
-------
systems with leak detection layers can provide some perspective on allowable
leakage rates per defect.
For the evaluation of localized fluid transmission at the
geomembrane/GCL interface (i.e. where "intimate contact" has not been
attained), the quantity of leakage through a defect is a function of the hydraulic
head, size of the defect, and the properties of the GCL. If a defect having an area
of 1 cm2 is considered with a constant head of 30 cm (I ft), then the leakage
quantity through a GCL specimen is mainly a function of the following GCL
properties:
Initial transmissivity of the upper GCL geotextile
Rate of hydration of the bentonite
Extrusion of bentonite into the upper GCL geotextile (i.e. long term
transmissivity of the upper GCL geotextile)
Continuity of the leakage source (i.e. steady state)
Vertical percolation rate through the GCL (initial and long term)
If it is assumed that bentonite can intrude into the pores of the upper
geotextile, the hydraulic transmissivity of that interface will decrease. While the
rate of leakage may be initially high, it could decrease with time to a level that is
insignificant in terms of the leakage quantities through the composite liner.
4.1.4 Ongoing Research
The issue of whether migrating bentonite can reduce the transmissivity of
the upper geotextile has been evaluated in laboratory research funded by the
GCL manufacturers. There has been a lot of attention paid to the initial leakage
rates as opposed to the longer term rate. With relatively small scale laboratory
GCL specimens (150 to 300 mm diameter), the fluid initially introduced to the
GCL through the geomembrane defect often flows out of a radial flow device
before the GCL can hydrate. If the test specimens were larger in diameter (600 to
1500 mm), it is conceivable that lateral flow from the edge of the specimens
would not be observed even from the GCL specimens with the highest initial
leakage rate. From a design standpoint, this is the critical behavior to quantify.
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To begin to define the role of a GCL in an "intimate contact" composite
liner, the investigation of the rates of hydration of larger GCL specimens at the
geomembrane interface should be coupled with ongoing research on GCL seams
and shrink/swell behavior to estimate the effective radius of saturation of a.GCL
This radius will determine the area that has been essentially saturated such that
vertical percolation through the bentonite component of the GCL will begin to
occur. This area can be used to estimate long term leakage through the
composite liner. This is the quantity that is of the greatest concern to the waste
industry and will provide the information necessary to evaluate the use of GCLs.
If the maximum computed leakage is acceptable, then GCLs can be considered as
a replacement for portions of or all of the compacted soil component.
4.2 Questions from the Audience
Upon the conclusion of his lecture, Mr. Bove held a question/answer
session where several important topics were discussed.
1) From the point of view of intimate contact, what is the difference between a
compacted clay liner and a GCL?
Ans) The use of a GCL potentially introduces an interface that allows flow. The
important point though, is how much flow occurs, and can we get sufficiently
low flow with either the compacted clay or the GCL?
2) As the upper geotextile of a hydrated GCL is said to be "plugged up" with
migrating bentonite, why is there such a concern for the transmissivity of the
upper geotextile?
Ans) From a regulatory standpoint, a geotextile is a geotextile whether it is
incorporated into a GCL or not. And if the placement of a geotextile beneath a
geomembrane is unacceptable, then the same goes for a GCL incorporating an
upper layer geotextile. One could make the geotextile thin enough that lateral
flow does not become a big issue over time, or one could have the mentality that
there is no geotextile that is satisfactory.
While manufacturers and testing companies may claim that once
hydrated, a GCL makes good contact with an overlying geomembrane, until this
is demonstrated on a full scale sample, some skepticism will remain.
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3) Could a layer of condensed water between a geomembrane and a compacted
clay liner be a potential pathway for lateral transmission?
Ans) Depending on the overburden stress, it would most likely provide a
localized pathway as opposed to a continuous one.
4) Which provides better intimate contact, a smooth or textured geomembrane?
Ans) This is a difficult question that depends on a lot of factors. For example, if
one has a very hard compacted clay liner and a textured geomembrane under
low normal loading, one could easily imagine high levels of lateral flow if the
geomembrane does not penetrate the liner.
5) If the concern revolves around a damaged geomembrane, why not place a
thick geotextile or a GCL protection layer on top of the geomembrane in order to
prevent damage as it is done in Germany?
Ans) This is a good point in that designers need to get out of the mode that a
GCL will just replace the layer of compacted clay. A new design philosophy is
necessary to realize the full potential use of a GCL.
4.3 Final Comments
Part of the purpose of displaying ranges of geotextile transmissivity data
was to show that the amount of water that can potentially move laterally the
geotextile component of a GCL is very small. Furthermore, the distance traveled
by this liquid is limited by GCL hydration. Mr. Bove stated that the risk of
significant leakage through a GCL in this mode is very small, especially in
double composite liner systems.
The question of intimate contact between a geomembrane and a
compacted clay liner was raised by several people. It was pointed out that
wrinkles in the geomembrane make intimate contact with a compacted clay liner
questionable.
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CHAPTER 5
OWNER/OPERATOR EXPERIENCES AND CONCERNS
Representatives from four waste disposal companies were given the
opportunity to voice their opinions on the use and performance of GCLs. While
one company representative was very confident of the ability of GCLs to
perform, the others expressed concerns over several technical issues.
5.1 Clarke Lundell, Representing Waste Management of North America, Inc.
Up to now, the use of GCLs has been limited to a backup role. Typically,
GCLs are placed as a redundant seepage barrier in secondary liner systems for
which only a single geomembrane liner is required. The company is reluctant to
make a general statement about whether a GCL can be used alone in the primary
liner when no secondary liner is present. This decision would be dependent on
the geologic conditions at the site.
There needs to be more information gathered about GCLs. While it
appears that the products do work, more work is needed to determine why they
work.
Some of the issues that need to be investigated are:
Intimate contact with a geomembrane
Frictional properties
Hydration and swelling
Quality assurance
Storage
Deployment
-What equipment should be used?
What about soft subgrade?
Weather factors
5.2 Charles Rivette, Representing Browning-Ferris Industries (BFI)
While GCLs have been used within the company, there is not a general
consensus on them yet. If one polled a representative from each of their 100
landfill sites, one would most likely get 100 different answers. Within their sites
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in the United States, the use of GCLs has mostly been limited to sumps, header
pipes, and as secondary containment for leachate and fuel storage. However, in
Italy, BFI has some sites in use, or permitted for later use, where a GCL is the
primary seepage barrier. The most likely future use of GCLs will be in cover
systems used to cap older landfills that were closed in the 1960s.
The company still has some concerns about the products. Some of these
concerns are:
Construction
There is still some concern about how to successfully install a GCL. An
example was given describing a site in Louisiana where a GCL was
installed below an HDPE geomembrane. Before installers could
completely seal off the upper geomembrane, a sudden rain storm
hydrated the yet unfinished liner. The effort involved in the ensuing clean
up and reinstallation was enormous.
Quality assurance/quality control (QA/QC)
QA/QC is not only important for construction, but for the
manufacturing of the products, as well.
Cost
Due to the high costs of clay in the Northeast, and along the West coast,
GCLs are more likely to be used. In the South and Midwest, where
suitable clay is readily available, compacted clay liners are going to
continue to be used extensively.
Interface friction
The use of canyons and valleys for landfill sites has become more
common. Unfortunately, during interim fill conditions there exists the
possibility of a massive wedge failure for bottom slopes of only 2 to 4 %.
While they would like to attain a factor of safety of 2 for their designs,
they often cannot even achieve a factor of 1.5 when using current interface
friction values in their analysis.
The values of interfacial friction angles measured so far have been
highly variable. They would like to see more repeatability of results.
At the present time, BFI has one site in use and at least three liners in the
process of design and/or obtaining a permit where a composite HDPE/GCL
-------
system is serving as the primary liner. In each case, the design is necessary due
to the lack of local clay soils at the site.
5.3 Kurt Shaner, Representing Chambers Development Company, Inc.
At the present time, Chambers operates or is in the process of permitting
20 municipal solid waste landfills. GCLs are incorporated into the liner system at
10 of these sites. Of these 10, 5 sites are in operation, 3 are permitted with
construction ongoing, and 2 are in the permitting process. The most common
application of the GCLs has been in the formation of primary composite liners at
double lined sites.
While the company views GCLs as a positive development in the area of
liner technology, is still has some concerns. Some of these concerns include:
Quality Assurance Standards
-Uniform procedures for the QA/QC of the manufacturing and
installation of GCLs are needed.
Shear Strength Determination
-Repeatable results for the testing of internal and interface friction need to
be determined. This testing should account for variables such as normal
stress, shear rate, amount of hydration, hydration liquid, etc. Potentially,
a data base could be created to correlate between each of the variable
parameters and frictional resistance.
Construction Considerations
-Some problems with premature hydration have been encountered due to
leaking trailers and precipitation events. While not a problem with the
performance of the material, it does illustrate a difficulty with the
installation of the product.
Perhaps the greatest benefit of the use of GCLs is the ease of their
installation compared to CCLs. The installation of GCLs does not require
compaction nor the control of moisture content and can be completed in cold
weather. The non-applicability of these factors improves the probable quality of
an installation, especially when placed to form a primary composite liner.
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5.4 John Workman, Representing Laidlaw Waste Systems
Due to the abundance of clay at each of their sites, Laidlaw has never
incorporated GCLs into any of their designs. For GCLs to be used at a future
date, the reliability of the product will have to be well established. Some of the
criteria used to ensure this reliability are discussed below;
Efficiency
The efficiency of a liner system refers to its ability to shed water.
Efficiency is a measure of the amount of leachate diverted to a drainage
sump versus the amount that percolates through the liner.
Damage resistance
There is the human element of big, bulky equipment being operated at
sites. This equipment, if improperly handled, can damage a liner.
Long term performance
Chemical resistance
Leakage potential
Break through potential
Constructability
Availability
The company is not opposed to the use of GCLs. It has just always
had a readily available source of clay at its sites. There are some sites that
do not have clay, and the use of a GCL may be warranted at these sites.
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CHAPTER 6
RECENT RESEARCH
Representatives from the University of Texas and Drexel University were
given the opportunity to discuss the results of the most recent research
undertaken at their respective universities. Research at the University of Texas
has tended to focus on large-scale hydraulic conductivity testing and on the
stability of final covers. Research at Drexel University has concentrated on the
hydration behavior, swelling characteristics, and internal shear strength of GCLs.
6.1 The Hydraulic Conductivity of Large Scale Intact, Overlapped, and
Composite Geosynthetic Clay Liners (By David Daniel University
of Texas)
The hydraulic conductivity of three 2.8 geosynthetic clay liners (GCLs)
was measured. The apparatus is shown in Fig. 6.1. Tests were performed on
Bentomatฎ, Claymaxฎ 200R, and Gundseal. The GCLs were placed above a
drainage medium and covered with 0.3 or 0.6 m of gravel. A constant hydraulic
head of 0.3 or 0.6 m was established. Tests were conducted on either a single
piece of material (control sample) or on two pieces of material that were
overlapped 37 or 75 mm. (Gundseal) or 75 or 150 mm. (Bentomatฎ and
Claymaxฎ 200R). Tests showed that overlapped panels self sealed; flow rates
through the overlapped GCLs were about the same as those through the control
samples.
A defective high density polyethylene (HDPE) geomembrane was placed
on top of samples of GCL material, covered with gravel, and then flooded with
water. Effective composite behavior did not occur with those GCLs that
contained a geotextile between the defective geomembrane and bentonite but did
occur for the GCL in which the defective geomembrane was in direct contact
with the bentonite in the GCL.
Further details on this research is provided by Estornell (1991) and
Estornell and Daniel (1992).
-------
Water
Surface
Geosynthetic
Clay Liner
(GCL)
Drainage
Hole
Drainage Layer
Acrylic Strip
Bentonite Seal
Drainage Outlet
System
Collection
Container
Note: Not to Scale
CORNER DETAIL
Bentonite
Drainage
Material
Acrylic Strip
75 mm
Figure 6.1 Cross Sectional View of Test Set Up
-------
6.2 The Effect of Differential Settlement on the Hydraulic Conductivity of
Geosynthetic Clay Liners (By Mark LaGatta and B. Tom Boardman,
University of Texas)
One of the more likely future uses of a GCL is as a component in the final
cover of a municipal solid waste landfill. Subsidence generally occurs beneath
the final cover due to biochemical decay of waste, collapse of underlying
materials, or consolidation of saturated waste material. Unlike a wide
embankment fill, the landfill will most likely not settle as a uniform mass. There
will be localized settlements randomly distributed across the cover.
Unfortunately, these localized settlements tend to cause the most damage to a
flexible cover due to tensile strains caused by large differential settlement.
In an attempt to determine the effects of settlement on the hydraulic
conductivity of a GCL, Mr. LaGatta modified the steel tanks developed originally
by Estornell. A wood frame and a large, deflatable, water-filled bladder were
placed in the bottom of each tank to allow settlement to occur. By opening a
valve beneath each tank, the rate and amount of settlement could be controlled
after the installation of the GCL (Fig. 6.2 and 6.3).
Both intact and overlapping samples were tested. A conservative overlap
of 225 mm was used. The overlapping samples were aligned with the overlap
running parallel to the length of the tank and the deflatable bladder. A non
symmetrical bladder was used to ensure one dimensional distortion and tensile
strains.
Mr. LaGatta has studied the effects of differential settlement on a hydrated
GCL. The full size GCL samples were hydrated within the tank after the GCLs
had been covered with 0.6 m of gravel. The valve to the bladder was then
opened, and a series of incremental settlements were induced beneath the GCL.
The effect of each incremental settlement on the hydraulic conductivity of the
deformed GCL was then closely monitored.
Intact and overlapping samples of Bentomatฎ, Claymaxฎ 200R, and
Gundseal were tested. The effective normal stress was approximately 7.6 kPa for
each test. The results are shown in Fig. 6.4 through 6.11. There was no measured
outflow for either the intact or overlapping samples of Gundseal at any
deformation.
-------
Grmular
Baiiom te
Side Seal
Vilve
1/8-in. O.D. InfUtion/
Deflation Line
Union
1/8-10 3/8-in. Tee
Reducer
Copper
Outlet Tube
Figure 6.2 Cross Sectional View of Modified Test Set Up
strip Tape Framc
Granular
Bcntonitc
Seal
Pea Gravel
Drainage
Course
2x 10
Wood 4x4 Wood
Frame Support
2.4 m
Figure 6.3 Plan View of Tank and Deflatable Bladder
-------
<0
>
t
>
H
O
13
Q
Z
o
o
g
_i
13
<
cc
Q
>
X
0 10 20 30 40 50 60 70 80 90 100 110
TIME (days)
Figure 6.4 Hydraulic Conductivity vs. Time for Intact Bentomatฎ Sample
EHS-2-D
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35
DEFORMATION, A / L
Figure 6.5 Hydraulic Conductivity vs. Deformation for Intact Bentomatฎ Sample
IHS-2-D
-------
E
u
10
10
>
t 10
O
Q 10
z
o
o
O 10
=>
<
(X
Q
>
X
10
10
10 20 30 40 SO 60 70 80 90
TIME (days)
Figure 6.6 Hydraulic Conductivity vs. Hme for Overlapped Bentomatฎ Sample
OHS-2-C
Note: Loose 0.25 lb/ft bentonite placed along outer edge of overlap as opposed to centerline of
overiap
0.2 0.3 0.4
DEFORMATION, A / L
Figure 6.7 Hydraulic Conductivity vs. Deformation for Overlapped Sample
OHS-2-C
-------
OT
E
o
O
13
Q
Z
o
o
o
-I
=>
<
cc
Q
>
X
30 40 50
TIME (days)
Figure 6.8 Hydraulic Conductivity vs. Time for Intact Claymaxฎ Sample EHS-l-A
10
10
E
o
>
ฃ
h
o
D
Q
Z
o
o
o
~
a 10
Q
>
X
10
-7
10
ฆ
>
c
ฆ"a
j
/
\
~
e
:
j
0.00 0.05 0.10 0.15 0.20 0.25 0.30 0.35
DEFORMATION, A/L
Figure 6.9 Hydraulic Conductivity vs. Deformation for Intact Claymaxฎ Sample
IHS-l-A
-------
a
z
o
a
_i
Z3
<
a:
a
>
x
Figure 6.10 Hydraulic Conductivity vs. Hme for Overlapped Claymaxฎ Sample
OHS-l-F
0.00 0.0S 0.10 0.15 0.20 0.25 0.30 0.35
DEFORMATION, A/L
Figure 6.11 Hydraulic Conductivity vs. Deformation for Overlapped Sample
OHS-l-F
-------
Mr. Boardman is studying the effects of differential settlement on
unhydrated, overlapping GCLs. After the installation of the dry GCL, a large
settlement is induced beneath the sample. The deformed GCL is then slowly
hydrated over a span of several days. The ability of the deformed sample to self
heal at the overlap is then closely monitored. The results of two tests are shown
in Fig. 6.12 and 6.13. Both intact and overlapping samples of Bentomatฎ,
Claymaxฎ, and Gundseal will be tested to determine the effect of the overlap. A
conservative overlap of 225 mm is being used. More details may be found in
LaGatta (1992).
6.3 Stability of Final Covers Placed on Slopes with Geosynthetic Clay Liners
(By Hsin-Yu Shan, University of Texas)
There has been some concern about the use of GCLs in sloping final cover
systems. Even with geogrid reinforcement, a GCL will lose strength and
potentially deform once hydrated. This concern needs to be addressed as GCLs
are expected to be more common in final cover systems.
A typical profile of a final cover incorporating a GCL is shown in Fig. 6.14.
The current slope design method is the limit equilibrium method. Unfortunately,
there is no way to predict the amount of deformation with this method. In an
effort to predict this deformation, Mr. Shan developed a numerical model
incorporating the properties of the top soil, geogrid, GCL, and cover soil. The
profile of the slope used in the model is shown in Fig. 6.15.
The model has been simplified by reducing the number of possible
interfacial friction values to the most critical one and by representing the tensile
resistance of all of the geosynthetics by one material (a geogrid). The top soil is
assumed to be 0.9 m thick and to have a unit weight of 15.7 kN/rn^. For the
range of expected normal stresses, O' and d are assumed to be 30ฐ and 4.8 kPa,
respectively, for the top soil. The degree of hydration of the GCL can be varied.
The numerical model was developed as a finite element program. Some
results of the model are shown in Fig. 6.16 and 6.17. As expected, for a given
slope, the lower the minimum interfacial friction angle, the higher the relative
displacement, and the higher the tension within the geogrid.
-------
10
10
-s
-6
10
>
H
>
H
U
=>
Q
Z
o
u
CJ
J
ซ 10 *8
a
>
JO
-9
ฆ
1 1
Beniomaiฎ OUS-l-H
230 mm of Overlap
Unhydrated Settlement of 75 mm
ฆ
>
6
3
a
z
O
u
u
13
3
<
ee
a
>
-8 .
-9
10
-10.
10
-11
GundsealC
230 mm o
Unhvdrau
3 OUS-l-F
f Overlap
'A Settlement o;
'75 mm
ฆ
-------
Top Soil
Drainage
Layer
FML
Geosynthetic
Clay Liner
Cover Soil
Waste
Figure 6.14 Typical Profile of Final Cover with Geosynthetic Clay Liners
ฆ Top Soil
' Geogrid
GCL
Cover Soil
Figure 6.15 Profile of the Slope Used for Computations
-------
0.5
0.4
E
o
(TJ
"5.
a
e
3
e
X
re
0.3
0.2
0.1
0.0
10
12 14 16
Interfacial Friction Angle (ฐ)
18
20
Figure 6.16 Relationship between Maximum Interfacial Displacement and
Minimum Interfacial Friction Angle for a 3:1 Slope
30000
-g- 20000
2
c
o
Vi
c
-------
While this analysis is still in its initial stages, it is hoped that by running
the model over a range of conditions one can draw conclusions about:
The probable short and long term shear strength parameters of GCLs
The possibility of using GCLs on slopes without excessive deformation
occurring
The usefulness of design schemes to reinforce the slope
6.4 The Hydration Behavior and Mid-Plane Shear Strength of Four
Geosynthetic Clay Liners (By Robert Koerner, Drexel University)
The focus of GCL research and development at Drexel University's
Geosynthetic Research Institute (GRI) is on the hydration behavior of the various
products and on their mid-plane shear strength. Work is ongoing with four
different commercially available products: Bentofixฎ, Bentomatฎ, Claymaxฎ,
and Gundsealฎ. Each of these products have been evaluated in five different
liquids: distilled water, tap water, mild leachate, harsh leachate, and diesel fuel.
The first series of tests focused on the hydration behavior under varying
normal stresses. These hydration tests were conducted on 150 by 150 mm
samples contained in steel boxes with perforated loading plates so that the
hydrating liquid was available to hydrate the entire surface area of the test
samples. The deformation curves shown in Fig. 6.18 display the following
information:
The products swelled from highest to lowest amounts in the following
order distilled water or tap water, mild leachate, harsh leachate, and
diesel fuel
For a given hydration liquid, Claymaxฎ swells the most, followed by
Gundsealฎ, Bentomatฎ, and Bentofixฎ in descending order. Clearly, the
needle punching of Bentomat ฎ and Bentofixฎ restrained the swelling in
these latter two products
Upon completion of the hydration tests, the samples were carefully
removed from their respective test devices and trimmed to fit in a 100 by 100 mm
direct shear test device. The location of the shear plane was set at the mid-plane
of each of the test specimens. The test specimens were sheared at a strain rate of
-------
E
E
c
o
to
E
0
ฎ
Q
E
3
E
1
2
r-O
tap water
ฆ ฆ
distilled water
~ - -
mild leachate
A
harsh leachate
~
diesel tuel
Normal Stress (kPa)
Results for Claymaxฎ
O
tap water
ฆ
distilled water
~
mild leachate
x
harsh leachate
ป
diesel fuel
40 60
Normal Stress (kPa)
Results for Bentomatฎ
a
E
E.
c
o
CO
E
w
O
*a>
Q
E
3
E
'5
2
O
tap water
ฆ
distilled water
mild leachate
ฆ-*
harsh leachate
~
diesel fuel
20 40
Normal Stress (kPa)
E
E
c
o
ca
E
i.
o
a>
a
E
3
E
'x
O
tap water
distilled water
a-.
mild leachate
it
harsh leachate
~
diesel tuel
20 40
Normal Stress (kPA)
Results for Gundsealฎ
Results for Bentofixฎ
-------
0.9 mm/min and were designated as "constrained-swell" tests. Direct shear tests
were conducted on all samples and counterpointed against parallel sets of tests
in the dry (or as received) state and also against "free-swell" tests in which the
test specimens were hydrated in the same liquids but without any normal stress.
The direct shear tests produced the shear strength parameters and c shown in
Table 6.1. The data indicate the following trends.
The products are strongest in the dry "as-received" condition and the
weakest in the free-swell condition. The constrained-swell condition is
intermediate between the two extremes.
Needle-punching significantly increases shear strength.
The hydrating liquid can affect strength.
Hydration with distilled water yields the lowest shear strength and can
be used as a conservative liquid.
Products with fiber reinforcement required much larger displacements
than urireinforced products to reach their limiting shear stress.
-------
Table 6.1 Direct Shear Test Results Summary (Drexel University)
Hvdratine Fluid
GCL Type
Measured Prooertv
Drv*
Constrained Swell"
Free Swell*"
Claymax
0 (degrees)
37
16
0
C(kPa)
6.9
3
4
Gundseal
0(degrees)
26
19
0
Distilled
C(kPa)
50
5
3
V-" iter
Bentomat
0 (degrees)
42
37
23
C(kPa)
14
6
5
Ben to fix
0 (degrees)
36
31
10
C(kPa)
68
7
9.0
Claymax
0 (degrees)
37
18
0
C(kPa)
6.9
3
3
Gundseal
0 (degrees)
26
18
0
Tap
C(TtPa)
50
5
3
Water
Bentomat
0(degrees)
42
43
26
C(kPa)
14
6
10
Ben to fix
0 (degrees)
36
34
15
C(kPa)
68
6.9
7
Claymax
0 (degrees)
37
24
4
C(kPa)
6.9
6
3
Gundseal
0 (degrees)
26
18
13
Mild
C(lcPa)
50
5
4
Leachate
Bentomat
0 (degrees)
42
39
25
C(kPa)
14
8J
14
Ben to fix
0 (degrees)
36
43
20
C(lcPa)
68
5
12
Claymax
0 (degrees)
37
19
0
C(lcPa)
6.9
6
3
Gundseal
0(degrees)
26
13
0
Harsh
C(kPa)
50
7.6
3
Leachate
Bentomat
0 (degrees)
42
45
32
C(kPa)
14
5
12
Bentofix
0 (degrees)
36
39
30
C(kPa)
68
4
8J
Claymax
0(degrees)
37
44
38
C(kPa)
6.9
4
6
Gundseal
0 (degrees)
26
24
29
Diesel
C(lcPa)
50
4
6
Fuel
Bentomat
0 (degrees)
42
42
40
C(kPa)
14
6
5
Bentofix
0(degrees)
36
51
46
C(kPa)
68
4
5
Notes:
* Dry refers to product as-received, placed under desired normal stress, then sheared at midplane.
** Constrained swell refers to product hydrited under desired normal stress, i.e_ constrained swell, then
sheared at midplane.
*** Free swell refers to product hydrited under zero normal stress, then placed under desired normal stress, and
then sheared at midplane.
-------
CHAPTER 7
EQUIVALENCY
7.1 Equivalency (By David Daniel, University of Texas)
7.1.1 Potential Applications
If one wants to substitute a geosynthetic clay liner (GCL) for a required
compacted clay liner (CCL), one will generally have to demonstrate that the
proposed GCL will provide equivalent or better performance to a CCL.
Equivalency analyses may be required for
Final Cover Systems:
Single GCL Versus Single CCL Liner
Geomembrane/GCL Composite Liner Versus Geomembrane/CCL
Composite Liner
Single Liner Systems:
Single GCL Versus Single CCL Liner
Geomembrane/GCL Composite Liner Versus Geomembrane/CCL
Composite Liner
Double Liner Systems:
Geomembrane/GCL Composite Liner Versus Geomembrane/CCL
Composite Liner in Primary Liner
Geomembrane/GCL Composite Liner Versus Geomembrane/CCL
Composite Liner in Secondary Liner
The Solid Waste Disposal Facility Criteria found at 40 CFR Part 258 apply
to municipal solid waste landfills and treat the area of "equivalency" differently
for final covers and liners. Final cover systems are to be designed to minimize
infiltration and erosion, therefore, designs other than the minimum requirements
of ง258.60 (a) could be approved using an "equivalency" demonstration.
However, alternatives to the composite liner design in ง258.40 (a) (2) are not
approved based on "equivalency" demonstrations but must meet the
performance standard at ง258.40 (a) (1). Different standards apply to facilities
-------
that receive hazardous waste regulated under Subtitle C of RCRA and to
CERCLA clean-up sites.
The designs for Subtitle C and CERCLA are evaluated based on the site-
specific design. Innovative use of modern materials is encouraged, providing
they meet the requirements of the law.
7.1.2 Differences Between CCLs and GCLs
Some of the differences between compacted clay liners and geosynthetic
clay liners are listed in Table 7.1. Some of the potentially important (depending
upon specific application) relative advantages of CCLs and GCLs may be
summarized as follows:
Advantages of compacted clay liners (CCLs):
The large thickness of CCLs makes them virtually puncture
proof
The large thickness of CCLs makes them relatively insensitive
to small imperfections in any one lift
The large thickness of CCLs gives them substantial capacity for
adsorption of leachate
The large thickness of CCLs delays the discharge of water and
solutes from the base of liners
There is a long history of use of CCLs
Intimate hydraulic contact with a geomembrane is not an issue
for CCLs
Many regulatory agencies require CCLs; use of another type of
liner may require demonstration of equivalency to a CCL.
A CCL is a logical choice if suitable clay is available locally
Testing procedures are reasonably well established for CCLs.
Advantages of geosynthetic clay liners (GCLs):
Small thickness of GCLs leads to low consumption of space
Construction of GCLs is rapid and simple
Heavy equipment is not needed to install a GCL, which is
beneficial if the GCL is underlain by a geosynthetic material
-------
Table 7.1 Differences Between GCLs and CCLs
Characteristic
Geosvnthetic Clav Liner
Compacted Clav Liner
Materials
Bentonite Clay, Adhesives,
Geotextiles, and
Geomembranes
Native Soils or Blend
of Soil and Bentonite
Construction
Manufactured and Then
Installed in the Field
Constructed in the
Held
Thickness
Approximately 10 mm
Approximately 05 to
1.0 m
Hydraulic
Conductivity
of Clay
10"10 to 10"ฎ cm/s
(Typical)
10"ฎ to 10"^ cm/s
(Typical)
Speed and Ease
Construction
Rapid, Simple
Installation
Slow, Complicated
Construction
Water Content
at Time of
Construction
Essentially Dry;
Cannot Desiccate
During Construction
and Produces No
Consolidation Water
Nearly Saturated;
Can Desiccate and
Can Produce
Consolidation
Water
Cost
$5 to $11
per Square Meter
Highly Variable
(Estimated Range:
S8 to S32 per
Square Meter)
Experience
Level
Limited Due to
Newness
Has Been Used for
Manv Decades
-------
Some inclement weather delays (e.g., freezing temperatures)
that stop construction of CCLs are not experienced with GCLs
Because a GCL is a manufactured material, a consistent and
uniform material can be produced
Because GCLs are manufactured materials many of the
specialized performance properties can be determined and need
not be repeatedly re-determined
GCLs can accommodate large differential settlement
Quality assurance is simpler for a GCL compared to a CCL
GCLs are more easily repaired than CCLs
GCLs can probably better withstand freeze/thaw and wet/dry
cycles than CCLs
Unlike CCLs, GCLs are not vulnerable to desiccation damage
during construction
7.1.3 Criteria for Equivalency
Three issues should be addressed when one compares a GCL to a CCL
and considers the equivalency of a GCL to a CCL:
1. Hydraulic issues
2. Physical /mechanical issues
3. Construction issues
The specific issues that might have to be addressed for a specific site are listed in
Table 7.2.
7.1.4 Hydraulic Issues
Hydraulic issues are the easiest to quantify. The criteria are discussed
separately.
7.1.4.1 Steady Flux of Water
Flux of water is usually assessed by comparing the long-term, steady state
water flux for the CCL and GCL. The flux of water (v) through an individual
layer of porous material is defined from Darcy's Law as:
-------
Table 7.2 Potential Equivalency Issues
Categ
orv
Criterion for Evaluation
Relevant for
Liners Covers
Hydraulic
Issues
Steady Flux of Water
Steady Solute Flux
Adsorption Capacity
Breakout Time:
-Water
-Solute
Production of Consolidation Water
X
X
X
X
X
X
Physical/
Mechanical
Issues
Freeze-Thaw
Wet-Dry
Total Settlement
Differential Settlement
Slope Stability
Erosion
Bearing Capacity
X
X'
X
X
X
X
X
X
Construction
Issues
Puncture Resistance
Subgrade Condition
Ease of Placement
Speed of Construction
Availability of Materials
Weather Constraints
Quality Assurance
X
X
X
X
X
X
X
X
X
X
X
X
X
X
Notes:
* Relevant only until liner is covered sufficiently to prevent freezing
** Settlement of liners usually of concern only in certain circumstances, e.g., vertical expansions
"* Stability of liner may not be relevant after filling (except canyon landfills)
-------
v= k (7.1)
where k is the hydraulic conductivity, H is the depth of liquid ponded on the
liner, and L is the thickness of the liner. The water pressure on the base of the
liner is assumed to be zero in Eq. 7.1.
For a GCL, Eq. 7.1 is applicable only for flow through the bentonite
component; if the GCL contains a geomembrane, water flux will be controlled by
water vapor diffusion through the geomembrane component. The geomembrane
component, if present, should be considered in the equivalency analysis and in
computation of water flux. Also, Eq. 7.1 applies to a CCL or GCL liner alone;
composite action with a geomembrane is considered later.
The flux ratio for water, Fw/ is defined as:
Fw=^ (7.2)
VGCL
VCCL
or:
h+Lgcl
^ Leo
h7ฃl
CCL Lccl
For example, for a GCL without a geomembrane component, if:
kcCL = 1 x 10-9 cm/s = 1 x 10"^ m/s
H = 0.3 m (1 ft)
Lgcl - 7 mm = 0.007 m
KcCL = 1 x lO'^cm/s = 1 x 10"^ m/s
LCCL = 0.9 m (3 ft)
then Fw from Eq. 7.3 equals 0.3. So long as Fw ^ 1, equivalency in terms of water
flux is demonstrated, i.e., the rate of water flow through the GCL is less than or
equal to that through the CCL. Most GCLs can be shown to be equivalent to a
CCL that has a hydraulic conductivity of 1 x 10"7 cm/s in terms of steady water
-------
flux. If the GCL contains a geomembrane, the flux ratio will be even less than
that computed from Eq. 7.3.
A composite liner consists of a geomembrane placed in contact with a low-
permeability soil. A geomembrane/GCL composite may be considered as an
alternate to a geomembrane/CCL composite. If so, flow through the composite
should be analyzed. Flow through a flaw in a geomembrane in a composite liner
depends on the hydraulic conductivity of the clay component, the hydraulic
gradient across the clay component, the hydraulic contact between the
geomembrane and the clay component, and the presence of a geomembrane
within the GCL. No equations have been published for computing flow rates
through a defect in a geomembrane component of a geomembrane/GCL
composite liner. However, published information can be used to make
comparative estimates. Equivalency evaluations would clearly be product and
perhaps site specific.
7.1.4.2 Steady Solute Flux
The maximum flux is the steady-state flux. Long-term, steady solute flux,
which is relevant only for liners, may be analyzed on the basis of advection
alone, diffusion alone, or advection plus diffusion. As will be seen later, the
assumptions necessary to analyze steady diffusion and steady advection-plus-
diffusion are inconsistent with the processes themselves, and only the case of
advection is relevant for steady-state conditions. Nevertheless, for completeness,
the methods for analyzing steady diffusion and steady diffusion-plus-advection
are presented so that these processes can be understood.
It is assumed that the concentration of a solute of concern in the leachate
remains constant. The advective mass flux, vm>A/ is:
, H + L
vm,A ~ Cleachate * l (7A)
where qeachate is the concentration of the solute of interest in the leachate. The
advective mass flux ratio, Fm,A is defined as:
_ vm A(GCL)
m,A = vm A(CCL) ^7-5)
-------
or:
, H + k:cL
ฐleachate ^GCL
Fm,A = j H + LCCl (7"6)
Qeachate ^CCL lccl
or:
h+Lgcl
^GCL Lgcl
CL ~lE5T
It is noted that qeachate cancels out of Eq. 7.6. Because Fm/A = Fw (Eq. 7.7), if one
has demonstrated equivalency of steady water flux, one has also demonstrated
equivalency of steady mass flux of solute caused by advection.
Solutes in leachate can also migrate through clay liners by molecular
diffusion. Steady diffusion of solutes is usually analyzed with Fick's first law,
which states that:
Ac
vD = D 0 "j- (7.8)
where vd is the diffusive mass flux, D is the diffusion coefficient for the solute of
interest, 6 is the volumetric water content, Ac is the difference in concentration of
the solute between the top and bottom of the liner, and L is the thickness of the
liner.
The diffusive mass flux ratio (Fm>o) is defined as
_ Fm D(GCL)
m,D = EXCCL) (7'9)
or:
DCCL eGCL
*m,D =
Ac
LgCL
Dccl ซCCL
(7.10)
-------
or:
p ฐGCL 0GCL krcL
m,D DCCL 0ccl LgcL { '
Limited data exist on diffusion coefficients in clay liners. Data developed for
compacted kaolinite at the University of Texas indicate that D=ป 6 x 10*10 m^/s
for the non-reactive solute chlorine. For one GCL tested, the diffusion coefficient
for the bentonite in the GCL was approximately 2 x 10*10 mVs. W/ for example,
one assumes:
Dqcl 2 x lO'lO
#GCL 0^ _
ฃ?CCL 04
Lcci. ฐ-9 m
= 129
LgCL 0.007 m
then one computes a diffusive mass flux ratio of:
Fm,D = (0-33) (1.5) (129) = 64
In this example, the GCL is not equivalent to the CCL since there would be more
diffusive mass flux through the GCL than CCL. In general the calculated steady,
diffusive mass flux through the bentonite within the GCL is always expected to
be greater than the steady, diffusive mass flux through the CCL. However, for
those GCLs that have a geomembrane component, the geomembrane, which has
an extremely low diffusion coefficient for most solutes, should be considered and
will tend to greatly reduce the steady, diffusive mass flux.
As mentioned earlier, the assumptions necessary for computing steady
diffusive flux are inconsistent with the process itself. The problem is that a
contradiction exists in the boundary conditions. Diffusion is .driven by a
concentration gradient, Ac Over time, the solute of interest in the leachate will
-------
diffuse to the base of the liner, and the concentration at the base of the liner will
eventually equal the concentration on top of the liner, i.e., the concentration in
the leachate (which is assumed to be constant). Thus, the diffusion-driving
concentration gradient becomes zero and diffusive transport ceases. The- only
way that steady diffusion could develop through a liner would be for fresh water
to continually flush the underside of the liner to maintain a concentration
gradient across the liner. For nearly all sites, the case of steady diffusion will be
irrelevant and need not be considered.
It may be argued that neither advection alone nor diffusion alone is
important solutes will migrate through soil liners by advection plus diffusion.
The total mass flux due to advection plus diffusion (vmfA+D) is generally
assumed to be:
vm,A+D = vm,A + vm,D (7.12)
and the ratio of advective plus diffusive mass flux, Fm>^+D' maX be defined as:
vm A+D (GCL)
Fm-A+D= vmA.D(Ca) <713>
Although Eq. 7.13 can be applied, it should not be applied because the
assumed conditions are physically impossible for long-term, steady conditions.
If advection carries solutes downward through the liner, then at steady state the
base of the liner must necessarily be saturated with leachate. If the base is
saturated with leachate, then Ac = 0 and vm>Q =0. Thus, when one analyzes long-
term, steady mass flux of a solute through a GCL or CCL, only advective
transport need generally be considered.
In some cases, one may wish to analyze transient conditions that lead up
to steady conditions, in which case both advective and diffusive transport should
be considered. If the GCL contains a geomembrane, the presence of the
geomembrane should be taken into account.
7.1.4.3 Adsorption Capacity
The adsorption capacity of a clay liner may be relevant only for liners (not
covers). Regulations generally have no specific adsorption requirements.
-------
Adsorption of organics tends to be different from adsorption by inorganics.
Adsorption of inorganics is controlled by cation exchange reactions and
geochemical processes such as precipitation. Adsorption of organic solutes is
generally assumed to be controlled by the amount of organic carbon in the soil
and a partition coefficient for the solute (which is characterized by the octanol-
water partition coefficient or water solubility of the organic species).
For inorganics, the maximum adsorbed mass per unit cross-sectional area
of liner (C) resulting from cation exchange processes may be defined as follows:
C = CEC pd L (7.14)
where CEC is the cation exchange capacity (maximum mass of solute sorbed per
unit mass of dry soil), pj is the dry mass density of the soil, and L is the
thickness of the liner. The ratio of thickness of a typical GCL to a CCL is small
(on the order of 0.01). Thus, in order for a GCL to have equivalent cation
adsorption capacity to a CCL, the adsorption coefficient of the GCL would have
to be at least 100 times that of the CCL.
The cation exchange capacity of bentonite clay is typically on the order of
100 to 150 meq/lOOg. Natural soil materials used to construct CCLs have typical
CECs in the range of 3 to 30 meq/lOOg. The ratio of cation adsorption capacities,
denoted F^eo ^
c CGCL CECGCL Pd GCL LGCL
Fcec "Cca * ceCccl Pd ccl ^ (7'15)
For the typical range of values, Fq?c would be expected to be in the range of 0.03
to 0.75. It appears unlikely that equivalency c&n be demonstrated for cation
adsorption capacity using the expressions just presented. However, it must be
understood that adsorption of inorganic species is a complex process. Cation
exchange is just one of several processes that can affect adsorption. Precipitation
of inorganic solutes can be a far more important mechanism than cation
exchange, and pH is often a dominant variable controlling precipitation
processes in many geochemical environments. Thus, site-specific factors, and not
just simple comparisons of CECs and relative soil masses, will often need to be
considered when relative adsorption capacities are compared.
-------
Non-polar organic solutes are sorbed by carbon present in the soil. The
carbon content of bentonite in GCLs is capable of estimation, but CCLs will be
highly variable in their organic carbon content. Although site-specific
assessments would be required (due to variability of. CCLs), equivalency of a
GCL to a CCL probably cannot be demonstrated in terms of capacity to adsorb
non-polar constituents in Ieachate to the bentonite because the mass of bentonite
present in a GCL is far less than the mass of soil present in a CCL.
Adsorption is only relevant in the short term. When steady state mass
transport is reached, adsorption capacity is exhausted. Equivalency in terms of
adsorption, if evaluated at all, should be evaluated in terms of a specified
performance period. For example, suppose the performance period being
considered is 30 years. If the adsorption capacity of neither the CCL nor the GCL
is exhausted after 30 years, both types of liner have "reserve" adsorption capacity
and may be considered equivalent for the performance period. Alternatively, if
either or both is exceeded, breakthrough of solute will occur and other issues,
e.g., steady state solute flux, will require consideration.
7.1.4.4 Time to Initiate Discharge of Water from Base of Liner
GCLs are initially unsaturated with water whereas CCLs are often very
close to saturation. When liquid first enters the upper surface of the liner, no
liquid initially discharges from the base of the liner. The GCL might be
compared to the CCL in terms of time to achieve discharge of water from the
bottom of the liner. Again, for those GCLs that contain a geomembrane, the
presence of the geomembrane should be taken into account.
The time to achieve discharge of water from the base is difficult to
describe in general terms. For CCLs, the time depends greatly upon the
hydraulic conductivity, initial water content, and tendency to swell. For GCLs,
the time is usually fairly short (a few weeks), although for GCLs that contain a
geomembrane, the time may be much greater. A comparison of time to initiate
discharge of water from the base of the liner would have to be performed on a
site specific basis.
The time to initiate discharge of water from the base of a liner is not
relevant in the long term and often will not be relevant even in the short term.
Most designs assume that water will be discharged from the base of a liner and
do not make any assumptions about how long this process will take.
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7.1.4.5 Breakthrough Time for Solute
The breakthrough time for a solute, which is not relevant for covers, is the
time required for a solute to travel from the top to the bottom of a liner.
However, theoretically, the time required for an infinitely small concentration of
solute to breakthrough to the base of a liner is zero for a thick or thin liner.
Thus, breakthrough time is not a uniquely defined parameter the time depends
upon the concentration of interest. In this section, it is assumed that the
breakthrough time for a GCL is compared to that of a CCL for the same
concentration at the base of the clay liner.
Because of the thinness of GCLs, diffusion will generally cause the
breakthrough time of a thin layer of bentoriite to be less than for a CCL. Even for
GCLs that contain a geomembrane, diffusion of organic solutes across the
geomembrane tends to occur quickly, but at a very low mass flux. However,
diffusion of inorganics through the geomembrane would be nil. Equivalency
depends on the GCL and the chemicals of concern.
One must carefully consider whether the breakthrough time for solutes is
relevant. In the long term, breakthrough time is irrelevant - breakthrough will
eventually occur in all liner systems with an outward gradient. The important
long-term issue is solute flux.
Steady-state flux represents a worst-case scenario, i.e., largest mass flux.
Time-dependent flux, before steady state, also may need to be considered in
certain situations.
7.1.4.6 Production of Consolidation Water
When clayey soils are loaded, water tends to be slowly squeezed out of the
soil via a process known as "consolidation." The production of consolidation
may or may not be of any concern, depending upon site-specific conditions.
Examples of potential problems associated with the production of consolidation
water include reduced stability at the geomembrane/clay liner interface (the
consolidation water from the clay liner tends to reduce stability through
increased water pressure at the interface) and collection of liquids in a leak
detection layer for double composite liners.
Compacted clay liners are nearly saturated with water at the time of
construction. When CCLs are loaded, substantial quantities of water are often
squeezed out of the liner. For example, if a 1-m-thick liner is saturated with
-------
water and compresses just 2 percent of its original thickness due to consolidation,
the amount of water squeezed out of the liner would be approximately 200,000
liters of water per hectare (20,000 gallons per acre).
Geosynthetic clay liners are essentially dry when they are constructed and
cannot produce consolidation water unless they are first soaked with water and
then compressed. Normally, GCLs do not have an opportunity to become
saturated before they are loaded. However, a saturated GCL will produce far
less consolidation water than a saturated CCL. Thus, GCLs are superior to CCLs
in terms of minimizing production of consolidation water.
7.1.5 Physical/Mechanical Issues
The physical/mechanical issues that might be considered in an
equivalency analysis include freeze/thaw effects, wet/dry effects, response to
total settlement, response to differential settlement, stability on slopes, and
vulnerability to erosion. Some issues are relevant for liners but all are relevant
for covers (Table 7.2).
7.1.5.1 Freeze/Thaw Resistance
Compacted clay liners are known to be vulnerable to large increases in
hydraulic conductivity from freeze/thaw. Limited laboratory data indicate that
GCLs do not undergo increases in hydraulic conductivity as a result of
freeze/thaw (Shan and Daniel, 1991). In addition, for those GCLs that contain a
geomembrane, the geomembrane is unaffected by freeze/thaw. Thus, from the
available data, GCLs appear to be superior to CCLs in terms of freeze/thaw
resistance.
7.L5.2 Wet/ Pry Effects
Wetting and drying of CCLs and GCLs can cause either type of clay liner
to swell or shrink. The main concern with clay liners that are wet and then dry
out, is that desiccation can lead to cracking and an increase in hydraulic
conductivity.
Limited laboratory data indicate that when dry, cracked CCLs are
rewetted, the clay swells and any cracks are partially dosed, leading to partial
recovery of the original, low hydraulic conductivity. In contrast, the available
data show that the high swelling of bentonite results in full self heading and full
-------
recovery of the original, low hydraulic conductivity when dried, cracked GCLs
are rewetted. In addition, for those GCLs that contain a geomembrane, the
geomembrane is insensitive to wet/dry effects. Thus, GCLs appear to be more
than equivalent to CCLs in terms of ability to self-heal if the material is wetted,
dried, and then rewetted.
7.1.5.3 Response to Total Settlement
Total settlement refers to block-like settlement without significant bending
or distortion. It is believed that GCLs and CCLs would respond similarly to total
settlement.
7.1.5.4 Response to Differential Settlement
Recent research by LaGatta (1992) indicates that some GCLs maintain their
low hydraulic conductivity even when subjected to large differential settlements.
In all probability, GCLs are more resistant to damage from differential settlement
than CCLs (LaGatta, 1992). For example, for a depression with a diameter of 1 m
that subsides 0.5 m, the liner will undergo approximately 10% tensile strain.
While the data discussed in LaGatta (1992) suggests that GCLs can function
under such conditions, it is known that CCLs cannot and will suffer tension
cracks at 1% tensile strain or less.
7.1.5.5 Stability on Slopes
The shear strength of GCLs is very sensitive to the water content and type
of GCL (Shan and Daniel, 1991; and Daniel and Shan, 1992). Water-saturated
GCLs that have adhesive-bonded bentonite have angles of internal friction for
consolidated-drained conditions of approximately 10 degrees. Dry materials are
2 to 3 times as strong as water-saturated GCLs. Also, needle-punched and stitch-
bonded GCLs tend to have high strengths. The shear strength of CCLs varies
widely, depending on materials, water content, and compaction conditions.
In stability analyses, one often must consider not only internal shear
failure but interfacial shear with an adjacent layer, e.g., a geomembrane. Also,
shear strength may be of short-or long-term concern, or both. No general
statement can be made about probable equivalency of a GCL to a CCL because
the assessment depends on specific materials, the degree to which the bentonite
-------
punctured by a piece of construction equipment. Thus, GCLs will not have
equivalent puncture resistance to CCLs. However, quality assurance and quality
control procedures can be established and implemented to make the probability
of a puncture during construction extremely low. Ultimately, site-specific
conditions and quality assurance procedures will determine whether puncture is
a relevant issue that deserves serious consideration.
7.1.6.2 Effect of Subgrade Condition
Compacted clay liners are constructed with heavy equipment. If the
subgrade is compressible (e.g, solid waste), the GCL, which can be installed with
light-weight equipment, will be easier to construct. On the other hand, stones
and rocks can puncture a GCL but not a CCL; if the subgrade contains stones or
rocks, the integrity of the GCL may be compromised. Thus, equivalency of a
GCL to a CCL in terms of the effect of subgrade depends on the condition of the
subgrade and will have to be evaluated on a site-specific basis.
7.1.6.3 Ease of Placement or Construction
A GCL will always be easier to place than a CCL, unless weather
conditions are adverse (e.g., constant rain), in which case even a CCL will also be
difficult to construct. In general, GCLs are equivalent to or better than CCLs in
terms of ease of placement or construction.
7.1.6.4 Speed of Construction
Geosynthetic clay liners can be placed much more quickly than CCLs.
Equivalency is obvious.
7.1.6.5 Availability of Materials
Suitable clays for construction of a CCL may or may not be available
locally, depending on the site. Because GCLs are a manufactured material, they
are readily available and can be shipped to a site quickly. The cost of shipment is
not a large percentage of the total cost of a GCL. Thus, GCLs will often be
superior to CCLs in terms of availability of materials.
-------
7.1.6.6 Weather Constraints
Compacted clay liners are difficult to construct when soils are wet, heavy
precipitation is occurring, the weather is extremely dry (clay desiccates), the soil
is frozen, or the temperature is below freezing. Geosvnthetic clay liners are
difficult to construct during precipitation. Weather constraints generally favor
GCLs.
Some GCLs must be covered before they get wet. If a geomembrane will
be placed over the GCL, the GCL must be covered almost immediately with the
geomembrane. Additional weather constraints, e.g., wind speed, may apply to
the geomembrane and, indirectly, influence the GCL. The fact that many GCLs
must be covered before they are hydrated is a significant weather constraint for
GCLs that does not exist for CCLs. However, CCLs have weather constraints,
too: CCLs must not be allowed to freeze or desiccate (GCLs cannot desiccate
during construction because they are dry, and dry GCLs are unaffected by
freezing temperatures).
Equivalency in terms of weather constraints must be considered on a site-
specific basis, but weather constraints generally favor GCLs over CCLs.
7.1.6.7 Quality Assurance Requirements
Quality assurance (QA) requirements are less extensive for GCLs
compared to CCLs, but no less critical. There is no reason to suspect that QA is
more difficult for a GCL than a CCL. However, testing procedures and
observational techniques are well established for CCLs but are not for GCLs. The
GCL industry and the Geosynthetic Research Institute (GRI) are working hard
through GRI and ASTM to established testing methods. While it would appear
that GCLs and CCLs are equivalent in terms of QA requirements, more work
needs to be done to establish standard test methods for GCLs.
7.1.7 Summary of Equivalency Issues
Table 7.3 summarizes the preceding discussion of equivalency.
Equivalency can be demonstrated generically in many categories. However, in
two categories, equivalency probably cannot be demonstrated: (1) GCLs do not
have adsorption capacity equivalent to CCLs; and (2) GCLs do not have the
puncture resistance of CCLs. The adsorption capacity has no relevancy to covers.
-------
Table 7.3 Summary of Equivalency Assessment
Equivalency of CCL to CCL
Cate;*
orv
Criterion for Evaluation
Probably Probably Product or
Equivalent Not Equivalent Site Specific
Hydraulic
Issues
Steady Flux of Water
Steady Solute Flux
Adsorption Capacity
Breakthrough Time:
-Water
-Solute
Consolidation Water
X
X
Physical/
Mechanical
Issues
Freeze-Thaw
Wet-Dry
Total Settlement
Differential Settlement
Slope Stability
Erosion
Bearing Capacity
X
X
X
X
X
X
X
Construction
Issues
Puncture Resistance
Subgrade Condition
Ease of Placement
Speed of Construction
Availability of Materials
Weather Constraints
Qualitv Assurance
X
X
X
X
X
-------
For liners, the issue of adsorption capacity may or may not be relevant,
depending on project-specific details. Although thin GCLs can be punctured
during construction, the problem is of more concern for liners (due to higher
stresses), and careful QA may be capable of addressing this potential problem for
both liners and covers.
As suggested by Table 73, many equivalency issues depend on the GCL
product and the particular conditions unique to a given site. Equivalency will
clearly have to be evaluated on a case-by-case basis.
7.2 Discussion
A brief discussion took place after the presentation. Comments were
made that there is a large need to establish criteria for analysis of equivalency.
The potential criteria are numerous, but many may not apply. Also, differences
in liners and covers were emphasized and the special problems in analyzing
geomembrane/clay liner composites were briefly discussed.
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CHAPTER 8
TECHNICAL CONCERNS
Even though a wide variety of research has been performed on
geosynthetic clay liners (GCLs), many people expressed concern about how
GCLs will perform in the field. The research, while providing some insight into
the properties of GCLs, can often be difficult to interpret and relate back to a real-
life field condition. Because of this, there are still unanswered questions and
concerns relating to the full-scale field behavior of GCLs. In an effort to identify
and address specific concerns, an open discussion was held.
8.1 The Effect of Freezing on Saturated Sodium Bentonite
The hydraulic conductivity of one GCL incorporating sodium bentonite
has been shown to be unaffected by several freeze/thaw cycles in one series of
laboratory experiments (Shan and Daniel, 1991). Similar results have been
obtained for other GCLs in tests performed in commercial laboratories. Thus, the
limited laboratory data show no detrimental effects from freeze-thaw but there
have been no full scale field tests performed to verify the results of laboratory
tests.
8.2 The Flow of Bentonite out of a GCL on a Side Slope
Bentonite would most likely not flow out of a GCL on a slope because:
If a GCL is installed with an overlying geomembrane, the chances are
that the GCL will never get sufficiently hydrated to allow the clay to
"flow".
If the GCL did become hydrated, consolidation would take place due
to the stress of cover soils, and the internal shear strength of the GCL
would go up.
If a needle punched or stitch bonded GCL is used it is difficult to
imagine the clay moving between the confining geotextiles.
-------
8.3 Designing for Side Slopes
Two sets of data are needed to design for side slope stability when using
GCLs:
1) Shear strength test data simulating the failure mode deemed important
by the designing engineer:
Short term direct shear tests
Long term creep tests
2) Wide width tensile strength data. When conducting this test, one must
consider the effect of confining stress on the results. Research at Drexel
University (1992) has shown that the confining stress will not influence
the tensile strength of a GCL incorporating a woven slit film geotextile.
8.4 Possibility of Overlaps Pulling Apart Due to Wet/Dry Cycles
This is why GCLs should always be installed with some sort of
overburden stress. Not only can the overburden soil prevent damage to the
GCL, but over burden will also prevent the overlap width from changing if moist
GCLs dry and shrink. The GCL products can also be modified to prevent
overlap movement. Bentofixฎ can be made with a velcro strip along the overlap,
Claymaxฎ or Bentomatฎ can be sewn (by hand) along the overlap as a prayer
seam with a strong monofilament thread, and the geomembrane components of
Gundseal can be welded together.
8.5 Steep Slopes
The use of geogrids and high strength geotextiles should be considered, as
the long term shear and tensile strength of a GCL is questionable.
-------
8.6 Long Term Physical Stability
Which will physically last longer, a GCL or a CCL? This depends on the
environment to which the liner will be exposed. While CCLs have traditionally
had problems due to desiccation cracking in hot, arid climates, GCLs have shown
the ability to quickly swell and self-heal even after being dried out. The mineral
components of both the CCL and GCL would hypothetically last forever as clay
is in the final stage of weathering. The long-term performance of the geotextiles
and needle punching is questionable, though.
8.7 Long Term Shear Strength
The internal shear strength of a GCL will go down as the bentonite
hydrates. How long will it take for a GCL to become hydrated? Is it reasonable
to assume that the entire GCL becomes hydrated?
8.8 Biotic Instabilities
How does one prevent animals and plants from burrowing into the final
cover? While a thick CCL could prevent damage, how can a thin GCL prevent
damage from occurring? One could possibly place a wire screen in the upper
layer, but how effective would this really be?
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CHAPTER 9
REFERENCES AND PUBLICATIONS RELATED TO GCLs
Alther, G. R. (1986), "The Effect of the Exchangeable Cations on the
Physiochemical Properties of Wyoming Bentonites," Applied Clay Science,
Vol. I, pp. 273-284.
Bruton, D. (1991), "Bentonite Mats Meet Secondary Containment Standards,"
Geotechnical Fabrics Report, Vol. 9, No. 4, pp. 26-27.
Clem, J. (1992), "GCLs Used Successfully in Hazardous Waste Containment,"
Geotechnical Fabrics Report, Vol. 10, No. 3, pp. 4-7.
Daniel, D. E., and P. M. Estornell (1991), "Compilation of Information on
Alternative Barriers for Liner and Cover Systems," U. S. Environmental
Protection Agency, EPA 600/2-91/002, Cincinnati, Ohio.
Daniel, D. E. ,and R. M. Koerner (1991), "Landfill Liners from Top to Bottom,"
Civil Engineering, Vol. 61, No. 12, pp. 46-49.
Daniel, D. E., and H. Y. Shan (1992), "Effects of Partial Wetting on Strength and
Hydrocarbon Permeability," Geotechnical Engineering Center, Univ. of
Texas, Austin, Texas, 56 p.
Daniel, D. E. and R. M. Koerner (1993), "Final Cover Systems," Geotechnical
Practice for Waste Disposal., D.E. Daniel (Ed.), Chapman & Hall, London, in
press.
Daniel, D. E. (1993), "Clay Liners,"Geotechnical Practice for Waste Disposal. , D.E.
Daniel (Ed.), Chapman & Hall, London, in press.
Eith, A. W., J. Boschuk and R. M. Koerner (1991), "Prefabricated Bentonite Clay
Liners," Landfill Closures: Geosynthetics, Interface Friction and New
Developments. Elsevier Applied Science/London, pp. 1193-218.
Elzea, J. M. and H. H. Murray (1990), "Variation in the Mineralogical, Chemical
and Physical Properties of the Cretaceous Clay Spur Bentonite in Wyoming
and Montana (U. S. A.)," Applied Clay Science, Vol. 5, pp. 229-248.
Estornell, P. (1991), "Bench-Scale Hydraulic Conductivity Tests of Bentonitic
Blanket Materials for Liner and Cover Systems," M.S. Thesis, University of
Texas, Austin, Texas.
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Estornell, P., and D. E. Daniel (1992), "Hydraulic Conductivity of Three
Geosynthetic Clay Liners," Journal of Geotechnical Engineering, Vol. 118, No.
10, pp. 1592-1606.
GeoSyntec Consultants (1991), "Final Report Laboratory Testing of Gundsealฎ,"
Report to Gundle Lining Systems, Inc., Norcross, Georgia, June 15, p. 62.
GeoSyntec Research Institute (1991), "Swelling Behavior and Shear Strength of
Gundsealฎ, in Distilled Water and Leachate," Report to Gundle Lining
Systems, Inc., Philadelphia, Pennsylvania April 18, p. 20.
Gibson, R.E. and D.J. Henkel (1954), "Influence of Duration of Tests at Constant
Rate of Strain on Measured 'Drained' Strength," Geotechnique, Vol. 4, pp. 6-
15.
Grim, R. E. (1968), Clay Mineralogy, McGraw Hill, New York.
Grube, W. E., Jr. (1991), "Soil Barrier Alternatives," Proceedings of the 17th Annual
RREL Hazardous Waste Research Symposium on Remedial Action, Treatment and
Disposal of Hazardous Waste, EPA/600/9-91/002, Cincinnati, pp. 436-444..
Grube, W. E., Jr. and D. E. Daniel (1991), "Alternative Barrier Technology for
Landfill Liner and Cover Systems," Paper No. 91-5.9, 84th Annual Meeting,
Air & Waste Management Association, Pittsburgh, 10 pp.
Grube, W. E., Jr. (1992), "Geosynthetic Liners Offer Cover Option," Environmental
Protection, May. pp. 29-33.
Koerner, R. M. (1990), Designing with Geosynthetics, Second Edition, Prentice-Hall,
Englewood Cliffs, NJ, 659 p.
Koerner, R. M. and D. E. Daniel (1992), "Final Cover Systems for Landfills," Civil
Engineering, Vol. 63, No. 5, pp. 55-57.
LaGatta, M. D. (1992), "Hydraulic Conductivity Tests on Geosynthetic Clay
Liners Subjected to Differential Settlement," M.S. Thesis, University of
Texas, Austin, Texas.
Oscarson, D. W., Dixon, D. A., and M. N. Gray (1990), "Swelling Capacity and
Permeability of an Unprocessed and a Processed Bentonite Clay,"
Engineering Geology, Vol. 28, pp. 281-289.
Reschke, A. E., and M. D. Haug (1991), "The Physio-Chemical Properties of
Bentonites and the Performance of Sand-Bentonite Mixtures," Proceedings,
44th Canadian Geotechnical Conference, Calgary, Vol. 2, pp. 62-1 - 62-10.
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Ross, C. S., and S. B. Hendricks (1945), "Minerals of the Montmorillonite Group,
Their Origin and Relation to Soils and Clays," U.S. Geological Survey
Professional Paper 205-B, U. S. Dept. Interior, 79 pp.
Scheu, C., K. Johannssen, and F. Saathoff (1990), "Non-Woven Bentonite Fabrics-
A New Fibre Reinforced Mineral Liner System," Geotextiles, Geomembranes
and Related Products., D. Hoet (Ed.), Balkema, Rotterdam, Vol. 2, pp. 467-472.
Schubert, W. R. (1987), "Bentonite Matting in Composite Lining Systems,"
Geotechnical Practice for Waste Disposal '87, R. D. Woods (Ed.), ASCE, New
York, pp. 784-796.
Shan, H.Y. (1990), "Laboratory Tests on a Bentonitic Blanket," M.S. Thesis,
University of Texas, Austin, Texas.
Shan, H. Y., and D. E. Daniel (1991), "Results of Laboratory Tests on a
Geotextile/Bentonite Liner Material," Geosynthetics '91, Industrial Fabrics
Association International (IFAD, St. Paul. Vol. 2 pp. 517-535.
Simpson, M. J. (1991), "A Prefabricated Bentonite Clay Liner "Landfill Closures:
Geosynthetics, Interface Friction and New Developments. Elsevier Applied
Science, London, pp. 187-192.
Sivapullaiah, P. V., et al. (1987), "Modified Free Swell Index for Clays,"
Geotechnical Testing Journal, Vol. 10, No. 2, pp. 80-85.
Struve, F. (1990), "Geomembrane-Clay Composite Liners," Landfill Closures:
Geosynthetics, Interface Friction and New Developments. Elsevier Applied
Science, London, pp. 177-180.
Trauger, R. (1991), "Geosynthetic Clay Liner Installed in a New Municipal Solid
Waste Landfill," Geotechnical Fabrics Report, Vol. 9, No. 8, pp. 6-17.
Trauger, R. (1992), "Geosynthetic Clay Liners: An Overview," Pollution
Engineering, May 15, pp. 44-47.
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Abraham, Alex
Albertz, Jim
Andeison, Jim
Arbaugh. Leo
Asgari, Said
Barry, David
Bates, Tom
Beal, Mike
Beck, Mary F.
Bhulani, Joginder S.
Boardman, B. Tom
Bohachek, Randy
Boschuk, Jr John
Bove, John A.
Brdicka, Ed
Brosnahan, Ray
Brown, Richard
Bruion, Daniel
Butler, Stevi
Cadwallader, Mark
Carmo, Joseph
Carpenter, Pauick
Carson, David A.
Case, Mark fe.
Chien PhD PE, Calvin C
Choi, Yoon-Jean
Christoph, Jerry P.
Cisler, Rick
Coffman, Glenn N.
Collins, Tom G.
Collins, Tim
Conner, Jack
Cranston, Michael D.
Creamer, Pฃ Pete
SEC Donohue
SEC Donohue
Gundle Lining Systems, Inc.
West Virginia DNR
Indiana Dept. of Env. Mgt. (IDEM)
W.U.S. Army - Corps of Engineers
TNS
Ohio EPA (NWDO)
U.S. EPA, Region 3
Westinghouse Savannah River Co.
University of Texas at Austin
SEC Donohue
J&L Engineering, Inc..
Hazen & Sawyer
Ohio EPA (DSIWM)
PO Technology
WyoBen Inc.
James Clem Corporation
U.S. Army Corps of Engineers
Gundle Lining Systems, Inc.
Carmo Environmental Systems
American Colloid/CETCO Manuf. L
U.S. EPA - RREL
Golder Associates Inc.
DuPont Chemicals
U.S. EPA.
National Seal Co.
Ohio EPA (NWDO)
Law Environmental Inc.
Huesker Inc.
SEC Donohue
Consultant
Chemical Waste Management
RMT Inc.
Appendix
List of Attendees
11785 Highway, Drive, Suite 100, Cincinnati, OH 4S241
11785 Highway, Drive, Suite 100, Cincinnati, OH 45241
19103 Gundle Road, Houston, TX 77073
1356 Hansford Street, Charleston, WV 25301
105 South Meridian Street, Indianapolis, IN 46206-6015
Bo* 1294 Downtown Station (CEMRO-HR-E), Omaha, NE 68101-1294
Environmental Hwy 13 E., Box 38, Tilden, IL 62292
347 N. Dunbridge Road, Bowling Green, OH 43402
841 Chestnut Bldg. (3HW52). Philadelphia, PA 19107
1995 S. Centennial Ave. Bldg 4. Aiken, SC 29803
904 W. 22nd Street #3. Austin, TX 78705
11785 Highway, Drive, Suite 100, Cincinnati, OH 45241
938 South Central Avenue, Canonsburg, PA 15317
4011 W. Chase Blvd.. Suite 500. Raleigh. NC 27607
1800 Watermark Dr., Columbus, OH 43266-0149
3150 1st Avenue, Spearfish, SD 57783
3044 Hesper Road, Billings. MT 59102
444 N. Michigan Ave., Suite 1600, Chicago. IL 60611
12565 West Center Road (CERMD-ED-TT). Omaha. NE 68144
19103 Gundle Road, Houston, TX 77073
1866 Maurice Ave., E. Meadow, NJ 11554
1500 West Shure Dr., Arlington Heights. IL 60004-1434
26 W. M. L. King Dr., ML-CHL, Cincinnati, OH 45268-3001
20000 Horizon Parkway-Suite 500, Ml. Laurel, NJ 08054
300 Bellevue parkway, Wilmington, DE 19809-3722
Region I 90 Canal St., Boston, MA 02203
1245 Corporate Blvd., Aurora, IL 60504
347 N. Dunbridge Rd.. Bowling Green, OH 43402
112 Town Park Dr., Kennesaw, GA 30144
PO Box 411529, Charlotte, NC 28241
11785 Highway, Drive. Suite 100, Cincinnati, OH 45241
6013 Tulip Hill Rd.. Columbus, OH 43235
35251 Old Skyline Road-POBox 471, Kettleman City. CA 93239
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Dinicl, David E.
University of Texas at Austin
ECI 9.102E (Civil Engineering), Austin, TX 78712
Dux, Kathy
Metcalf &. Eddy
2880 Corporate Exchange Drive, Suite 2S0, Columbus, OH 43231
Datin, Dermis L.
Oklahoipa Stale
Dept. of Health 1000 NE 10th Street (SWMS 0206), Oklahoma City, OK 73117
Davis, Steve
Indiana Dept. of Env. Mgi.
(IDEM)IOS South Meridian Stieet, Indianapolis, IN 46206-6015
DeHavilltnd, Annette
Ohio EPA/CDO
2309 Westbrooke Dr.-Bldg. C. Columbus. OH 43228
DiCarlo, Daniel
Kelchner Environmental
6834 Loop Road, Centerville, OH 45489
Dobras, Thomas N.
James Clem Corp.
444 N. Michigan Avenue, Chicago, 1L 60611
Doughty, Joe
Arkansas Dept. of Pollution Control & Ecology
8001 National Drive, Little Rock, AR 72209
Douglas, Robert
Tri-Sute Controls
4460 Lake Forest Dr.. Suite 214. Cincinnati, OH 45242
Duffy, Dan
SEC Donohue
17250 Newburgh Street, Livonia, MI 48152
Dutta, PE. Subijoy
U.S. EPA
Alternative Technology Section (OS341), 401 M St. SW, Washington, DC 20460
Dzieibicki, Ted
National Seal Co.
1255 Monmouth Blvd., Galesburg, IL 61401
Ebelhar, Ron
SEC Donohue
11785 Highway, Drive, Suite 100, Cincinnati, OH 45241
Ellis, Marcia
New York State
DEC 50 Wolf Rd #230, Albnay,, NY 12233
Emara, Mpuz
Indiana Dept. of Env. Mgt. (IDEM)
105 South Meridian Street, Indianapolis, IN 46206-6015
Englande^, Linda
National Seal Company
1245 Corporate Blvd., Aurora, IL 60504
Ericluon,1 Allan
CH2M Hill
310 W. Wisconsin Ave., #700, Milwaukee, WI 53201
Faleh, Bassam H.
Tennessee Dept. of Env. Conservation
Custom House, 701 Broadway, 4th Floor, Nashville, TN 37423-1535
Fitzsimm^ns, Todd
Franklin. Richard J.
Eastern Petroleum Assoc.
PO Box 6327, Syracuse, NY 13217
Fluid Systems Inc.
32 Triangle Park Drive-Suite 3201, Cincinnati, OH 45246
Frobel, Pp. Ronald K.
R. K. Frobel & Associates
PO Box 1184, Old Saybrook, CT 06475
Fiuendt, Joel
National Seal Co.
1245 Corporate Blvd., Aurora, IL
Genthe, PE, Doug
RMT Inc.
P. O. Box 8923, Madison. WI 53708
Getwein,jAllen J.
U.S. EPA-Office of Solid Waste
401 M Street SW (OS-301), Washington, DC 20460
Getz, Eria
Ohio EPA (NWDO)
347 N. Dunbridge Rd., Bowling Green, OH 43402-0466
Gingericlj, Joe
GofT, Bruce E.
Oregon DEQ
811 SW 6th Avenue, Portland, OR 97204
Ohio EPA (DWPC)
2195 Front Street, Logan. OH 43138
Gray, Steven R.
Bentonite Corporation
1999 Broadway, Suite 4300, Denver, CO 80202
Gray, Richard A.
Chemical Waste Management
35251 Old Skyline Road-POBox 471, Kettleman City. CA 93239
Green, Wjlliam A.
William A. Green & Associates
106 S. Decatur, Maiden, MO 63863
Green, Nfncy
William A. Green & Associates
106 S. Decatur, Maiden, MO 63863
Gmbe, Walter E.
James Clem Environmental Corp.
23 Gordon St., Box 88, Fairmount, GA 30139
Guerrettaz, John
Indiana Dept. of Env. Mgt. (IDEM)
105 South Meridian Street, Indianapolis, IN 46206-6015
Hargrovej PE, John
Browning-Ferris Industries
757 N. Eldridge Rd.. Houston, TX 77079
Harris Pf^ Joseph
Poly Flex, Inc.
2000 W. Marshall Dr.. Grand Prairie. TX 75051
Harris, Stan A.
Fuller, Mossbarger, Scott <& May
0018 International Blvd., Cincinnati, OH 45246
Harris, PE. Jeff
Browning-Ferris Industries
757 N. Eldridge Rd.. Houston, TX 77079
Heerten, Georg
Naue Fasertechnik GmbH & Co. KG
Watturmstr. I D-4990 Lubbecke 1, Germany
Heidenrich, Scott
Ohio EPA (NWDO)
-------
Heisey, J. Scott
American Electric Power
1 Riverside Plaza, Columbus, OH 43213
Hester, Scott
Ohio EfA (DSIWM)
1800 Watermark Dr., Columbus, OH 43266-0149
Hewitt, Dennis
Terrafix. Geosynihetics, Inc.
42S Attwell Drive, Rexdale, Ontario, Canada M9W SC4
Hiadari, Ghodrat
Indiana Dept. of Env. Mgt. (IDEM)
105 South Meridian Street, Indianapolis, IN 46206-6013
Holm, John D.
U.S. Army - Corps of Engineers
601 E. 12th St. (CEMRK-HR-D), Kansas City. MO 64106-2896
Morton, Jim
U.S. EPA - RREL
Cincinnati, Oil
Houthoofd, Janet M.
U.S. EPA - RREL
26 W. M. L. King Dr., Cincinnati, OH 45268-3001
Unnotti, Joseph J.
NY State DEC
50 Wolf Road, Albany. NY 12233
Jaxos, David L.
U.S. Army - Corps of Engineers
12565 West Center Road (CERMD-ED-TT), Omaha, NE 68144
Johnston, David
Arkansas Dept. of Pollution Control St Ecology
8001 National Drive, Little Rock, AR 72209
Kang, Seuk W.
Ohio EPA(DHWM)
1800 Watermark Dr., Columbus, OH 43266
Kivalek, Laura
Asahi Chemical Industry America,
Inc. 350 5th Avenue, Suite 7412, New York, NY 10118
Kelly, Tom
U.S. EPA - Region 9
75 Hawthorne Street, San Francisco, CA 94105
Koemer, Robert M.
Drexel U/Geosynthetic Research Institute
Rush Bldg. #10, West Wing, 33rd A Lancaster, Philadelphia, PA 19104
Kolbasuk, Gary
National Seal Company
1255 Monmouth Blvd., Galesburg, IL 61401
Korkzan, Mohammad
Indiana Dept. of Env. Mgt. (IDEM)
105 South Meridian Street, Indianapolis, IN 46206-6015
Kreiger, Fran
SEC Donohue
11785 Highway, Drive, Suite 100, Cincinnati, OH 45241
Kreinbrink, Mark J.
Rumpke Sanitary Landfill, Inc.
10795 Hughes Road, Cincinnati, OH 45251
LaGaUa, Mark D.
University of Texas at Austin
Cockrell Hall #9.227, Austin. TX 78712
Landreth, Robert G.
U.S. EPA RREL
26 W. M. L. King Dr.. ML-CHL. Cincinnati. OH 45268-3001
Lipinski, Thorn
Ohio EPA (DSIWM)
1800 Watermark Dr., Columbus, OH 43266-0149
Lundell PE, .Clarke M.
Waste Mgt. or NA. Inc.
500 Cypress Creek Rd. West, Suite 300, Ft. Lauderdale. FL 33309 6127
Lydick, Larry D.
National Seal Co.
1245 Corporate Blvd., Suite 300, Aurora, IL 60504
Mabry, Lance Q.
Indiana Dept. of Env. Mgt. (IDEM)
105 S. Meridian, Indianapolis, IN 46206-6015
Maroun, Fadi
Ohio EPA (SWDO)
40 Main Street, Dayton, OH 45402
McAughan, Charles
Dentonite Corporation
1999 Broadway, Suite 4300, Denver, CO 80202
Mellema, Gregory J.
Miles, William
U.S. Army - Corps of Engineers
Box 1294 Downtown Station (CEMRO-HR-E), Omaha, NE 68101-1294
Bentonite Corporation
1999 Broidway, Suite 4300, Denver, CO 80202
Mills, Clive
Terrafix Gesoynlhetics, Inc.
425 Attwell Drive, Rexdale, Ontario, Canada M9W 5C4
Milne, Bruce R.J.
Fluid Systems Inc.
32 Triangle Park Drive-Suite 3201, Cincinnati, OH 45246
Moreland, Richard F.
Department of Public Works
4701 Shepherd Parkway, SW, Washington, DC 20032
Morgan, Michael
National Seal Co.
1245 Corporate Blvd., Aurora, IL 60504
Mossbarger, William
Fuller, Mossbarger, Scoit A. May
1409 N. Forbes Road, Lexington, KY 40511
Motan. E. Sabri
SEC Donohue
3003 Buiierficld Kaod. Oak Brook, IL 60521
Nagda, Durge S.
Kentucky Dept. of Env. Prot.
18 Reilly Rd.. Frankfort. KY 40601
Naranjo, Carlos R.
Ogden Env. St Energy Systems
PO Box 22879, Knoxville. TN 37933-0879
Noble, Syothia
Tribble & Richardson Consulting Engineers
51 Century Blvd., Nashville, TN 37214
North, Don
Ohio EPA (NWDO)
347 N. Dunbridge Rd., Bowling Green, OH 43402-0466
Overmann, Leo
Colder Associates, Inc.
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Panico, Caroline
Parker, JerTy
Patel, Maheth K.
Peggs, PhD. PE. Ian D.
Pieper, Tim
Pliska, Bob
Powdl, David
Prinlic, Kurt
Raychowdury, Anup
Reed. Jeff,
Reed, Lance
Repeiio, Pedro C.
Rivene, PE, Charles
Rockaway, Thomas D.
Roelker, ^on
Scott, John W.
Scott, PE(|
Sena, Mary E.
Serrato, Mike
Shan. Hsin-Yu
Shiner, Kurt
Sheets, Dlna
Sheridon, Teny
Shindala, Adhan
Simpson, Martin
Single, James
Skahn, Kenneth R.
Squyres, Wesley
Staab, Fred
Stam, Thomas
Stanton PE.
Stewart, Bob
Slief, Klaus
Strachm. PE,
Struve, Fred
Sutch, Bany T.
Swan, Robert II.
Taliaferro, 111,Lindsay
Tanner. W. Tracy
National Seal Company
Ohio EfA (NWDO)
Bechtel.Savannah River Inc.
I-Corp International
Tri-State Controls
SEC Donohue
Fluid Systems Inc.
Ohio EPA (NEDO)
Indiana Dept. of Env. Mgt. (IDEM)
SEC Donohue
National Seal Company
Golder Associates Inc.
Browning-Fcnis Industries
American Electric Power
SEC Donohue
Fuller, Mossbarger, Scott & May
Stephen LFuller, Mossbarger, Scott &. May
PRC Environmental Management
Westinghouse Savannah River Co.
University of Texas at Austin
Cham ben Development Co.
American Electric Power
Tensar Enviro. Systems
Misissippi State University
James Clem Corporation
Golder Construction Services, Inc.
U.S. EPA-Orfice of Solid Waste
Oklahoma Stale Department of Health
National Seal Company
American Colloid/CETCO Manuf. Liner
I. WayneCulpepcr Engineering
U.S. EPA Region 7 (RCRA Branch)
Umweltbundesamt
William M.Rumpke Waste Systems
Gundle Lining Systems, Inc.
Golder Associates Inc.
GeoSyntec Consultants
Ohio EPA
Fluid Systems Inc.
1245 Corporate Blvd. Suite 300, Aurora, IL 60504
347 N. Dunbridge Rd., Bowling Green, OH 43402-0466
802 E. Martintown Road, North Augusta, SC 29841
639 East Ocean Avenue, Suite 404, Boynton Beach, FL 33435
4460 Lake Forest Dr., Suite 214, Cincinnati, OH 45242
3003 Butterfield Road, Oak Brook, IL 60521
32 Triangle Park Drive-Suite 3201, Cincinnati, OH 45246
2110 E. Aurora Rd., Twinsburg, OH 44087
105 South Meridian Street, Indianapolis, IN 46206-6015
3003 Butterfield Road, Oak Brook, IL 60521
PO Box 1448, Galesburg, IL 61401
20000 Horizon Parkway-Suite 500, Mt. Laurel, NJ 08054
757 N. Eldridge Rd., Houston. TX 77079
1 Riverside Plaza, Columbus, OH 43215
11785 Highway, Drive, Suite 100, Cincinnati, OH 45241
1409 N. Forbes Road, Lexington, KY 40511
1409 N. Forbes Road, Lexinglon, KY 40511
11030 White Rock Road-Suite 190, Rancho Cordova, CA 95670
PO Box 616, CCC Bldg. 4. Aiken, SC 29802
606 W. 51st St. #104, Austin. TX 78751
3200 Highlands Parkway, Suite 400, Smyrna, GA 30082
One Riverside Plaza, Columbus, OH 43215
1405 3rd Ave., Suite 8, Spring Lake, NJ 07762
PO Drawer CE. Misissippi State, MS 39762
444 N. Michican, #1610, Chicago, IL 60611
520 Fellowship Road, Suite A-113. Mt. Laurel. NJ 08054
401 M Street SW (OS-220W), Washington. DC 20460
1000 NE lOih Street (SWMS 0206), Oklahoma City, OK 73117
1245 Corporate Blvd., Suite 300, Aurora, IL 60504
1500 West Shure Dr., Arlington Heights, IL 60004-1434
PO Box 733, Locust Grove, VA 22508
726 Minnesota Ave., Kansas City, KS 66101
(Wissenschaftlicher) Bismarckplatz I, D-100, Berlin 33, Germany
10795 Hughes Road, Cincinnati, Oil 45251
19103 Gundle Road. Houston, TX 77073
20000 Horizon Parkway-Suite 500, Mt. Laurel, NJ 08054
5950 Live Oak Parkway, Suite 330, Norcross, GA 30093
1800 Watermark Dr., P.O. Box 1049, Columbus, OH 43266-0149
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J TECHNICAL REPORT OATA
(Pleaie read Instructions on the reverse before completing)
1. REPORT NO.
2.
3. RECIPIENT S ACCESSION NO.
4. TITLE ANO SUBTITLE
Report of Workshop on Geosynthetic Clay Liners
5. REPORT OATE
6. PERFORMING ORGANIZATION COOE
7. AUTHOft(S)
David E, Daniel and B. Tom Boardman
8. PERFORMING ORGANIZATION REPORT NO.
9. performing organization name ano aooress
Department of Civil Engineering
University of Texas at Austin
Austin, TX 78712
10. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME ANO AOORESS
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, OH .45268
13. TYPE OF REPORT ANO PERIOO COVERED
14. SPONSORING AGENCY COOE
15. SUPPLEMENTARY NOTES
Michael H. Roulier 513-569-7796
16. ABSTRACT
A workshop was held in Cincinnati, Ohio, to discuss the most recent information
on the use of Geosynthetic Clay Liners (GCL's). Manufacturers discussed technical
developments, recent research results, quality control and compared GCL's to compacted
clay liners (CCL's). There are no standard test methods and no standard method was
agreed upon. A discussion of performance indicated that GCL's provided low hydraulic
conductivity, but more information is needed to quantify geomembrane and GCL composite
behavior, and to confirm recent research at the University of Texas and at Drexel
University, which indicated that most GCL's tested maintained low hydraulic conducti-
vity even when subjected to large differential settlement.
KEY WORDS ANO DOCUMENT ANALYSIS
I. DESCRIPTORS
b.IDENTIFIERS/OPEN ENOEO TERMS
C. COSATI Field/Croup
Lining
Bentonite
Clays
Tensile Strength
Sheer Strength
Geosynthetic
Clay Liners
Geotextile
Geomembrane
18. DISTRIBUTION STATEMENT
19. SECURITY CLASS (This Report 1
21. NO. OF PAGES
20. SECURITY CLASS (Tlut p
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ATTACHMENT N
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Bulletin #101
IANJTEC y TECHNICAL TIPS
Itnorui Control Tichnoiogies
Landfill Fires
There are two types of landfill fires:
~ Above ground - surface fires usually occur on the landfill working
face The fire is easily discovered and extinguished by suffocation
and/or removing the sourcfe of combustion If ignored, the fire can
grow large and become dangerous
~ Underground - subsurface fires usually start out small and
localized If left unattended, the fire can spread and can be
extremely difficult to extinguish
Requirements for fires - All must be present to support
combustion
~ Combustible materials - especially those with a low threshold for
combustion such as petroleum based products, tars and oils
~ Elevated temperatures - high temperatures are required to
initiate combustion Temperatures generated during aerobic and
anaerobic decomposition within a landfill can reach as high as
160ฐ F (70ฐ C)
~ Oxygen - air is essential for combustion. Control a fire's air supply
and you can smother a fire
Differences between surface & subsurface fires
I.I Surface fires are extinguished by removing combustible
materials, ignition sources (heat) or oxygen
~ Subsurface fires are far harder to control. Combustible materials
are not easily removed and temperatures cannot be easily
changed However, if the source of oxygen is eliminated or
sufficiently restricted, the fire can be smothered Typically this
provides the best approach
Sources of Oxygen intrusion into the landfill
I I Passive Air Intrusion sources are cracks/fissures in the cover,
inadequate cover material, wind impaction on the surface, or
diffusion of the atmosphere through the surface.
I I Active Air Intrusion - collection system design Poorly designed
gas collectors can allow air intrusion at the well-bore or into
shallow collection zones Subsurface piping not designed to with-
stand soil loads and landfill settlement can break along collection
headers or laterals near the surface prompting air intrusion
1 I Active Air Intrusion - operation of collection system Excessive
gas extraction is called "overpull" Localized overpull caused by
an improperly operated or balanced gas extraction system can
cause air intrusion
Preventing Underground Fires
~ Prevention is the best policy Eliminate conditions which can
initiate subsurface fires
~ Eliminate atmospheric intrusion through fissures and cracks in the
cover The solution is to repair them and maintain the cover Poor
surface cover or no cover is not permissible.
~ Well-bore seals must be effective to prevent intrusion Common
seals are Bentonite (clay), native soil, and impermeable barriers
like LANDTEC's Well-Bore Seal (WBS-100)
ฆ Bentonite seals dry out, crack and may leak Bentonite settles
at a different rate than surrounding trash and expands and
contracts at a different rate than the surrounding cover
ฆ Native soil seals are cheap and available but can be very
porous and settle at different rates than the surrounding trash
ฆ Well-bore seals such as LANDTEC's WBS-100 provide an
effective seal because they extend beyond the well-bore
region and are made of impermeable materials They also
prevent landfill gas leakage at the well casing/landfill interface
~ Operation of the gas collection system can be improved by
utilizing proper flow control at each gas extraction wellhead to
prevent overpull and air intrusion. This can minimize the potential
for fires A properly designed wellhead, such as LANDTEC's Accu-
Flo series, provides important data that can help a landfill techni-
cian prevent and/or detect subsurface fires before they become
serious or spread LANDTEC's Accu-Flo wellhead provides the
technician with the following information
ฆ An integrated gas temperature indicator
ฆ Built-in flow metering to determine accurate gas extraction
flow rates at the wellhead
ฆ A port for sampling gas composition, i.e methane, oxygen,
carbon dioxide levels in the landfill gas
ฆ Ports for measurement of the static and impact pressures at
the wellhead
If you suspect a fire exists
I I Check local ground temperatures If elevated, perform a soil
temperature survey of the surface to determine the spatial distribu-
tion of the elevated temperatures with respect to background
temperatures
I I Inspect the surface of the landfill in the vicinity of the suspected
fire for fissures, cracks, erosion, or other areas where air (oxygen)
may be readily entering the landfill
I I Monitor the gas temperature of the extraction wells in the fire
area to determine if elevated gas temperatures are present
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Technical Tips
Landfill Fires page 2
If You Suspect a Fire Exists (continued)
~ Monitor the carbon monoxide levels in the gas extraction wells in
the suspected area to determine if elevated levels of carbon
monoxide are present (Carbon monoxide gas is a by-product of
combustion)
~ Inspect the gas wellheads internal components in the impacted
area for the presence of soot and combustion odors
~ Inspect the suspected area for signs of smoke or vapor (best seen
in the early morning) emitting from the surface of the landfill
~ Inspect the ground around the impacted area for signs of acceler-
ated subsidence USE CAUTION - subsurface fires can undermine
areas of the landfill that could result in collapse of surface areas
and creates an extremely hazardous situation for personnel who
could fall into an extremely hot pit Areas that are suspect
should be barricaded and safety precautions taken Bulldozers
and heavy equipment must be kept away from the region until it
is deemed safe. REMEMBER - DO NOT WORK ALONE - USE
SAFETY PRECAUTIONS AT ALL TIMES.
~ Inspect the gas extraction system for signs of damage due to heat
or combustion Turn off, isolate or bypass affected systems Seal
damaged wells. Reduce the gas extraction rates from all operat-
ing wells in the affected area to minimize atmospheric intrusion
Is the fire shallow or deep?
~ Use the data obtained from surveying the surface soil tempera-
tures and from monitoring the gas extraction wells flow rates and
gas temperatures to help determine the intensity of the fire and
potential depth
Shallow fires
~ Cautiously excavate the fire zone and completely remove all
combustible materials Inspect the affected area to determine
that temperatures within the excavation have returned to back-
ground levels Backfill the excavation with clean inert material
and replace the cover material to its original integrity
~ Continue to monitor soil surface temperatures to ensure that they
have returned to normal background levels
In Conclusion
~ Never underestimate the potential danger of a landfill fire A
proactive approach in preventing landfill fires is the safest and
most cost-effective method
~ Practice preventive measures each and every day to keep the
potential for fires at a minimum
~ Most importantly, maintain the landfill surface cover and operate
the gas extraction system as required to prevent air intrusion into
the landfill
Additional LANDTEC Information
Product and technical information is available on LANDTEC's well-
heads, well-bore seals, knock-outs, pumping stations, instrumentation,
condensate/leachate treatment, flares and landfill gas management
software
LANDTEC also provides technical and educational literature on
specific landfill subjects and issues Please call our toll free West
Coast number 1-800-821-0496 (8 am - 5 p m ) for additional informa-
tion or placement on our mailing list
The above suggestions and information may not apply to all
situations and are offered only as general advice.
Deep fires
~ Use precautionary measures mentioned earlier Eliminate any and
all potential sources of atmospheric intrusion
D Reduce the gas extraction rates at all wells in the vicinity of the
fire
~ Continue monitoring gas extraction rates and gas temperatures to
determine if the fire is diminishing
~ Fill-in any surface subsidence and restore landfill cover grading as
required
~ If the above fails, consider the following measures (given the
proper authorization from regulators) Inject water into the fire
zone to quench it Saturate the surface cover with water each day
to maximize its seal and minimize air intrusion Other options
include smothering the fire by injecting liquid nitrogen or carbon
dioxide into existing or new wells placed in the zone of the fire
(costly)
LAN3TEC
LANOMLl CONTKOt Tf CHN 0 LOG IE S
6055 E Washington Blvd
Commerce, California 90040
1213) 722-8202, (800) 821-0496
FAX (2131 724-5742
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ATTACHMENT O
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Bulletin #103
IAN3TEC
TECHNICAL TIPS
Landfill Control Tichnoiogies
Health & Safety Issues
Landfill Owners/Operators Employer Responsibilities
Includes the health and safety of all on-the-job employees includ-
ing short and long-term exposure to potential hazards while working
at a landfill site Employers'
~ Must determine which landfill jobs bring employees in contact
with vapors, liquids and particulates that could cause short or
long-term health problems
~ Must comply with the numerous health and safety laws that apply
to normal working activities, engineering, construction, excavation
and drilling activities Specialized activities require separate
plans, programs and training in accordance with applicable
regulations
Liability
~ Federal and state laws mandate requirements and place the
burden of proof on the employer to demonstrate regulatory
compliance.
~ Safety and health issues must be adequately addressed to avoid
significant potential liability problems.
Employer Must Demonstrate Adequate Compliance
~ Employers must provide health and safety programs and training
for potential hazards that could be encountered while working on
the landfill site including
ฆ Exposure to dangerous gases - hydrogen sulfide, carbon
monoxide, methane and others.
ฆ Exposure to dangerous chemicals - vinyl chloride, benzene,
toluene, methylene chloride, etc.
ฆ Exposure to unsanitary or infectious wastes
ฆ Exposure to dangerous minerals and compounds - including
asbestos, heavy metals, acids and caustics
ฆ Exposure to radioactive materials.
ฆ Exposure to shock-sensitive compounds that may violently react
or explode
ฆ Exposure to a combination of working conditions that might
promote heat stress, dehydration, hearing loss, or breathing
difficulties
Required Health and Safety Programs
Individual state OSHA statutes typically address the following
I I Accident Prevention Program (General Safety)
I I Hazard Communication and "Right-To-Know" Program
I I Respiratory Protection Program
I I Medical Monitoring Program
~ Safety Training Program including Hazardous Materials and
Hazardous Waste Site Training, if applicable (29CFR1910 120)
~ Personnel and Work Environment Monitoring Program
~ Record Keeping & Maintenance for all of the above programs
Accident Prevention Program
~ A written Accident Prevention Program is the first basic building
block of an overall Health and Safety Plan
~ The program should cover company policies, objectives, specific
assignments of responsibility, the availability and location of
resources
Hazard Communication Standards
~ The Hazard Communication Program must inform and train
employees how to safely use the various chemicals with which
they come in contact.
~ Material Safety Data Sheets (MSDS) must be maintained on-site
and personnel must be trained in their understanding and use
ฆ Survey the site for all products, even those only used occasionally
ฆ Keep MSDS files updated and accessible Require that
employees and subcontractors working on-the site be made
aware of the file according to "right-to-know" programs
Respiratory Protection Program
~ A written respiratory protection program is legally required at sites
where it is necessary to employ the use of respiratory protection
equipment.
ฆ Site characterization will identify the need for protection from
organic vapors, acid gases, and particulates
ฆ Respirators are not approved for use against vapors which have
poor warning properties
III There is considerable specialized training required before
respirators are used at a site
[. I Many activities on municipal solid waste landfills may be safely
done without respirators However, there are many instances
where protection will be required and qualified parties may have to
provide them when drilling, excavating, trenching, working in
confined spaces, or doing hot work in potentially dangerous
environments
Medical Monitoring Program
I I This may be required for work on hazardous waste sites depending
on project-specific conditions On sites which are permitted as non-
hazardous but may contain hazardous materials or emit known
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Technical Tips
Health & Safety Issues page 2
Medical Monitoring Program (continued)
hazardous constituents at concentrations which may be above a
specified level of concern, the need for, and extent of medical
surveillance becomes a legal and business decision
~ Superfund Sites require a medical monitoring program for 30 years
for all involved staff
Safety Training Program
~ Safety is another basic program that has several functions
ฆ Teaches and informs employees about basic safety concerns
ฆ Addresses job-specific hazards likely to be encountered
ฆ Fulfills certain legal notification and training requirements under
state and federal laws.
ฆ Heightens employee awareness in general about safety.
~ If work includes potential exposure to hazardous materials at
hazardous waste sites, then very specialized training will be
required
Personnel & Work Environment Monitoring Program
~ An employer must monitor employees and/or the work environment
whenever they know, or suspect, there may be a risk for employee
exposure
~ Threshold exposure limits must be evaluated by a thorough site
characterization survey. Due consideration should be given to
uncontrolled environments and changing conditions, such as during
well drilling activities.
~ Monitoring or sampling techniques may include equipment that
provides protection or alerts those in the work environment
including: methane sensors, combustible gas analyzers, hydrogen
sulfide monitors, carbon monoxide detectors, oxygen analyzers, etc
They may be used regularly or during certain specific activities such
as drilling, trenching, excavation or other work
~ Monitoring perimeter or additional sampling should be determined
based on the types of hazards, risks present, and the extent of
exposure for the work to be performed
Records Maintenance
~ Accurate, reproducible, and verifiable records are essential for an
effective overall health and safety program
~ Where specific compliance cannot be easily demonstrated, various
records and programs may indirectly show the intent to comply
Program Implementation
LI To be effective, health and safety programs must be practical and
clear Hazards, risks, and dangers must be put in proper perspective
or the program can become very costly and unwieldy The burden of
proof for compliance of a program is squarely on the employer
I I Effective programs deal with all the issues, and balance the trade-
offs that are required to deal with changing guidelines and
standards
I "I The more industry participates in the promulgating of the standards,
and develops the specialized training required, the more realistic
and workable programs become
I I There are real costs involved in program implementation Do not
discount them
ฆ Specialized equipment may be required for proper monitoring
ฆ Site characterization and testing is expensive.
ฆ Special clothing, masks, ear plugs, and other gear impact O&M
ฆ Don't forget to include the costs necessary to monitor and
upgrade programs on a regular basis
~ Excessive, unrealistic or inappropriate controls can lead to safety
risks and cause accidents and injuries. Good common sense and
good judgement should be allowed to prevail
In Conclusion
~ Employers will incur additional health and safety issues once landfill
gas control begins at a landfill site Likewise, needs and responsi-
bilities will change as the site changes from open to closed
~ Besides providing new equipment and supplies, management must
diligently review and enforce compliance until new habits and
procedures are developed. Also, the new rules and requirements
must be included in updated job descriptions
~ Management must establish routine audit and monitoring programs
to assure compliance.
~ It is easy to become complacent. Continued training, ongoing
discussion, re-evaluation, quality control auditing, and updating of
programs is necessary at regular intervals
The above suggestions and information does not apply to all
landfills or situations and is offered only as a generic guideline.
State and federal laws and specific company policies can
change at any time.
A special thanks to James H Wheeler, author of Safety and Liability in
Landfill Gas Recovery and Control - Concepts. Trends and New
Concerns which was presented at the 10th International Landfill Gas
Symposium of the GRCDA(SWANA), February, 1987 Used with
permission
Additional LANDTEC Information
Information on LANDTEC's products which are specifically designed
to work together in landfill applications include landfill gas collection
products, measurement & instrumentation equipment,
condensate/leachate treatment systems, flares and landfill gas man-
agement software
LANDTEC also has additional technical and educational literature
on specific landfill subjects and issues Please call our toll free number
1 -800-821 -0496 (8 am -5pm West Coast time) for additional
information or placement on our mailing list
.A, IAN3TEC
Landfill Control Technologies
6055 E Washington Blvd
Commerce, California 90040
(213)722-8202, (800)821-0496
FAX (213) 724-5742
(0 199/ I
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RCRA SUBTITLE D COURSE EVALUATION QUESTIONNAIRE
Please indicate how you feel about the following components of the course.
Please rate each presentation as follows: 1 - excellent/highly relevant
2 - very good
3 - satisfactory
4 - marginally satisfactory
5 - unsatisfactory/poor
Please explain your answers where possible.
QUESTION 1 2 3 4 5 COMMENT
1. How would you rate this
course in terms of
meeting your needs for
Subtitle D technical
training?
2. How would you rate the
following items?
a. Selection of topics
covered.
b. Rate at which topics
were covered.
c. Educational level at
which topics were
covered.
d. Detail in which
topics were covered.
e. Balance of theory
with application.
f. Use of the manual as
a learning tool.
g. Use of the manual as
a future reference
tool.
h. How well the
different
topics/chapters
blended together to
support each other.
i. Use of charts and
tables in the manual.
j . Use of visual aids as
a learning tool.
k. Ability of the course
to hold your
interest.
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COURSE EVALUATION QUESTIONNAIRE (Continued)
Please make whatever additional comments you think are relevant to an evaluation
of this course. You may want to expand upon comments made in various portions
of this questionnaire or to say something you have not had an opportunity to say.
Please specify number of years working with facilities that manage solid waste
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