OSWER DIRECTIVE 9502.00-6C
RCRA FACILITY INVESTIGATION (RFI) GUIDANCE
VOLUME IV OF IV
CASE STUDY E
\ <
^V NULY1987
—x. \ >/
/ASTE MANAGEMENT DIVISION
OFFICE OF SOLID WASTE
U.S. ENVIRONMENTAL PROTECTION AGENCY
-------
ABSTRACT
On November 8, 1984, Congress enacted the Hazardous and Solid Waste
Amendments (HSWA) to RCRA. Among the most significant provisions of HSWA are
§3004(u), which requires corrective action for releases of hazardous waste or
constituents from solid waste management units at hazardous waste treatment.
storage and disposal facilities seeking final RCRA permits; and $3004(v), which
compels corrective action for releases that have migrated beyond the facility
property boundary. EPA will be promulgating rules to implement the corrective
action provisions of HSWA, including requirements for release investigations and
corrective measures.
This document, which is presented in four volumes, provides guidance to the
owner or operator of hazardous waste management facilities as to the conduct of
the second phase of the RCRA Corrective Action Program, the RCRA Facility
Investigation (RFI). Instruction is provided for the development and performance of
an investigation based on determinations made by the regulatory agency as
expressed in the schedule of a permit or in an enforcement order issued under
HSWA§3008(h). The purpose of the RFI is to obtain information to fully characterize
the nature and extent of releases of hazardous waste or constituents. This
information will be used to determine whether interim corrective measures or a
Corrective Measures Study will be necessary.
-------
DISCLAIMER
This Draft Report was prepared for the U.S. Environmental Protection Agency
by the NUS Corporation, Waste Management Services Group, Gaithersburg, MD
20878, in fulfillment of Contract No. 68-01-7310, Work Assignment No. 5, and is
based on previous work performed by Alliance Technologies, Inc., under Contract
No. 68-01-6871. The opinions, findings, and conclusions expressed herein are those
of the authors and not necessarily those of the U.S. Environmental Protection
Agency or the cooperating agencies. Mention of company or product names is not
to be considered an endorsement by the U.S. Environmental Protection Agency.
This document is intended to assist Regional and State personnel in exercising
the discretion conferred by regulation in developing requirements for the conduct
of RCRA Facility Investigations (RFIs) pursuant to 40 CFR 264. Conformance with this
guidance is expected to result in the development of RFIs that meet the regulatory
standard of adequately detecting and characterizing the nature and extent of
releases. However, EPA will not necessarily limit acceptable RFIs to those that
comport with the guidance set forth herein. This document is not a regulation (i.e.,
it does not establish a standard of conduct which has the force of law) and should
not be used as such. Regional and State personnel must exercise their discretion in
using this guidance document as well as other relevant information in determining
whether an RFI meets the regulatory standard.
n
-------
ACKNOWLEDGEMENTS
This document was developed by the Waste Management Division of the
Office of Solid Waste (OSW). Mr. George Dixon was the EPA Work Assignment
Manager and Mr. Art Day was the Section Chief. Additional assistance was provided
by Ms. Lauris Da vies and Mr. Paul Cassidy.
Guidance was also provided by the EPA RFI Work Group, including:
George Furst, Region • Janette Hansen, PSPD
Andrew Bellina, Region II Lisa Feldt, HSCD
William Smith, Region II Stephen Botts, OECM
Jack Potosnak, Region III Chris DeRosa, OHEA
Douglas McCurry, Region IV James Durham, OAQPS
Francine Norling, Region V Mark Guilbertson, OWPE
Lydia Boada Clista, Region VI Nancy Hutzel, OGC
Karen Flournoy, Region VII Steve Golian, OERR
Larry Wapensky, Region VIII Dave Eberly, PSPD
Julia Bussey, Region IX Jackie Krieger, OPPI
Melanie Field, Region IX Lisa Lefferts, PSPD
Jim Breitlow, Region IX Florence Richardson, CAD
Paul Day, Region X Reva Rubenstein, CAD
David Adler, OPPE Steve Sisk, NEIC
Joanne Bahura, WMD
This document was prepared by the NUS Corporation, Tetra Tech, Inc., and
Labat Anderson, Inc., and was based on previous work performed by Alliance
Technologies, Inc. The principal authors included:
Todd Kimmell, NUS Tom Grieb, Tetra Tech
Kurt Sichelstiel, NUS Kay Johnson, Tetra Tech
William Murray. NUS Bill Mills, Tetra Tech
Ron Stoner, NUS Nick Pangaro, Alliance
John George, NUS Linda Marler, Alliance
Ray Dever, NUS Andrea Mysliki, Labat Anderson
Dave Navecky, NUS
in
-------
RCRA FACILITY INVEST1ATION (RFI) GUIDANCE
VOLUME IV
CASE STUDY EXAMPLES
TABLE OF CONTENTS
SECTION PAGE
ABSTRACT j
DISCLAIMER ii
ACKNOWLEDGEMENTS iii
TABLE OF CONTENTS iv
TABLES viii
FIGURES x
LIST OF ACRONYMS xiii
IV
-------
VOLUME IV CONTENTS (Continued)
SECtlON
14.0
14.1
14.2
15.0
INTRODUCTION
USE OF CASE STUDIES
ORGANIZATION OF VOLUME IV
CASE STUDIES
CASE STUDY 1.
CASE STUDY 2.
CASE STUDY 3.
CASE STUDY 4.
CASE STUDY 5.
CASE STUDY 6.
CASE STUDY 7.
CASE STUDY 8.
CASE STUDY 9.
CASE STUDY 10.
CASE STUDY 11.
USING SOIL CHARACTERISTICS TO ESTIMATE
MOBILITY OF CONTAMINANTS
ESTIMATION OF DEGRADATION POTENTIAL OF
CONTAMINANTS IN SOIL
USE OF SPLIT-SPOON SAMPLING AND ON-SITE
VAPOR ANALYSIS TO SELECT SOIL SAMPLES
AND SCREENED INTERVALS FOR MONITORING
WELLS
CONDUCTING SITE INVESTIGATIONS IN TWO
PHASES
MONITORING BASEMENT SEEPAGE
USE OF PREDICTIVE MODELS TO SELECT
LOCATIONS FOR GROUND-WATER
MONITORING WELLS
MONITORING AND CHARACTERIZING
GROUND-WATER CONTAMINATION WHEN
TWO LIQUID PHASES ARE PRESENT
*
PERFORMING A SUBSURFACE GAS
INVESTIGATION
USE OF THE SUBSURFACE GAS MODEL IN
ESTIMATING GAS MIGRATION AND
DEVELOPING MONITORING PROGRAMS
DESIGN OF A SURFACE WATER MONITORING
PROGRAM
USE OF BIOASSAYS AND BIOACCUMULATION
TO ASSESS POTENTIAL BIOLOGICAL EFFECTS
OF HAZARDOUS WASTE ON AQUATIC
ECOSYSTEMS
14-1
14-1
14-1
15-1
15-1
15-10
15-14
15-22
15-27
15-31
15-36
15-41
15-48
15-57
15-66
-------
VOLUME IV CONTENTS (Continued)
SECTION
CASE STUDY 12.
CASE STUDY 13.
CASE STUDY 14.
»
CASE STUDY 15.
CASE STUDY 16.
CASE STUDY 17.
CASE STUDY 18.
CASE STUDY 19.
CASE STUDY 20.
CASE STUDY 21.
CASE STUDY 22.
CASE STUDY 23.
CASE STUDY 24.
SAMPLING OF SEDIMENTS ASSOCIATED WITH
SURFACE RUNOFF
SAMPUNG PROGRAM DESIGN FOR
CHARACTERIZATION OF A WASTEWATER
HOLDING IMPOUNDMENT
USE OF AIR MONITORING DATA AND
DISPERSION MODELING TO DETERMINE
CONTAMINANT CONCENTRATIONS
DOWNWIND OF A LAND DISPOSAL FACILITY
USE OF METEOROLOGICAL DATA TO DESIGN
AN AIR MONITORING NETWORK
USE OF THE 40 CFR 261 LISTING BACKGROUND
DOCUMENTS FOR SELECTING MONITORING
CONSTITUENTS
SELECTION AND EVALUATION OF A SOIL
SAMPUNG SCHEME
SAMPUNG OF LEACHATE FROM A DRUM
DISPOSAL AREA WHEN EXCAVATION AND
SAMPUNG OF DRUMS IS NOT PRACTICAL
CORRELATION OF CONTAMINANT RELEASES
WITH A SPECIFIC WASTE MANAGEMENT UNIT
USING GROUND-WATER DATA
WASTE SOURCE CHARACTERIZATION FROM
TOPOGRAPHIC INFORMATION
SELECTION OF GROUND-WATER MONITORING
PARAMETERS BASED ON FACILITY WASTE
STREAM INFORMATION
USING WASTE REACTION PRODUCTS TO
DETERMINE AN APPROPRIATE MONITORING
SCHEME
USE OF AERIAL PHOTOGRAPHY TO IDENTIFY
CHANGES IN TOPOGRAPHY INDICATING
WASTE MIGRATION ROUTES
IDENTIFICATION OF A GROUND-WATER
CONTAMINANT PLUME USING INFRARED
AERIAL PHOTOGRAPHY
15-77
15-80
15-86
15-93
15-100
15-105
15-109
15-114
15-118
15-121
15-125
15-129
15-134
VI
-------
VOLUME IV CONTENTS (Continued)
SECTION
CASE STUDY 25.
CASE STUDY 26.
CASE STUDY 27.
CASE STUDY 28.
CASE STUDY 29.
CASE STUDY 30.
CASE STUDY 31.
CASE STUDY 32.
CASE STUDY 33.
PRESENTATION OF DATA COLLECTED DURING
FACILITY INVESTIGATIONS
USE OF QUALITY ASSURANCE/QUALITY CONTROL
(QA/QC) AND DATA VALIDATION PROCEDURES
CORRECTIVE ACTION AND THE IMPLEMENTATION
OF INTERIM MEASURES
METHODOLOGY FOR CONSTRUCTION OF
VERTICAL FLOW NETS
USE OF DISPERION ZONE CONCEPTS IN THE
DESIGN OF A SURFACE WATER MONITORING
PROGRAM
EXAMPLE HEALTH AND SAFETY PLAN
USE OF HISTORICAL AERIAL PHOTOGRAPHS AND
FACILITY MAPS TO IDENTIFY OLD SOLID WASTE
MANAGEMENT UNITS AND POTENTIAL GROUND-
WATER FLOW PATHS
USE OF MULTI-STATION AMBIENT AIR
MONITORING AND THE EMISSION ISOLATION
FLUX CHAMBER TO CHARACTERIZE A
CONTINUING RELEASE TO AIR
(To Be Provided)
USE OF LEACHING TESTS TO ESTIMATE POTENTIAL
FOR INTER-MEDIA TRANSPORT
(To Be Provided)
15-140
15-154
15-164
15-
15-
15-
15-
15-
15-
VII
-------
TABLES
NUMBER PAGE
14-1 Summary of Points Illustrated 14-2
15-1 Relative Mobility of Solutes 15-5
15-2 Model Results 15-53
15-3 Relationship of Dissolved and Sorbed Phase Pollutant 15-61
Concentrations to Partition Coefficient and Sediment
Concentration
15-4 Parameters Selected for Surface Water Monitoring Program 15-62
15-5 Selected Surface Water Monitoring Stations and Rationale 15-63
15-6 Mean Concentrations (ug/l) of Organic Substances and Trace 15-70
Metals in Leachate and Surface Waters
15-7 Mean Sediment Concentrations (ug/kg Dry Wt) of Organic 15-71
Substances and Trace Metals
15-8 Mean Liver Tissue Concentrations (ug/kg Wet Wt) of Organic 15-72
Substances and Trace Metals
15-9 Mean LC50 and EC50 Values (Percent Dilution) for 15-73
Surf ace-Water Bioassays
15-10 Relative Toxicity of Surf ace-Water Samples 15-74
15-11 Arsenic and Lead Concentrations (ppm) in Runoff 15-79
Sediment Samples
15-12 Summary of Sampling and Analysis Program for Waste Water 15-83
Impoundment
15-13 Comparison of Measured and Predicted Vinyl Chloride 15-90
Concentrations (ppb)
15-14 Uses and Limitations of the Listing Background Documents 15-101
15-15 Indicator Parameters 15-123
15-16 Resultsof Monitoring Well Sampling 15-126
15-17 Average Values of Parameters in Ground Water and Stream 15-139
Samples
15-18 Summary of Data Collected 15-144
VIII
-------
TABLES (continued)
NUMBER PAGE
15-19 Typical Methods for Graphically Presenting Data Collected 15-153
During Facility Investigations
15-20 Results of Original Surface Soil and Tap Water Analyses 15-158
15-21 Laboratory QC Results 15-160
15-22 Field QC Results 15-161
15-23 Ground-Water Elevation Sumrrfary Table Phase II 15-
15-24 Relationship of Dissolved and Sorbed Phase 15-
•Contaminant Concentrations to Partition
Coefficient and Sediment Concentration
15-25 Parameters Selected For Surface Water 15-
Monitoring Program
15-26 Selected Surface Water Monitoring Stations and 15-
Selection Rationale
IX
-------
FIGURES
NUMBER PAGE
15-1 Schematic Cross-Section of Waste Disposal Site 15-3
15-2 Hypothetical Adsorption Curves for a) Cations and 15-6
b) Anions Showing Effect of pH and Organic Matter
(Millset al., 1985)
15-3 Schematic Diagram Showing Plumes of Total Dissolved 15-9
Solids (IDS), Total Organic Halogens (TOX) and Heavy
Metals Downgradient of Waste Disposal Site
15-4 Results of Laboratory Bench Tests for Pesticide 15-12
Degradation (from King et al., 1985)
15-5 Site Plan Showing Disposal Areas and Phase I Well 15-15
Locations
15-6 Geologic Cross-Section Beneath Portion of Site 15-17
15-7 Ground-Water Elevations in November 1984 15-18
15-8 Example of Borehole Data Including HNU and 15-19
OVA/GC Screening
15-9 Proposed Phase II Soil Borings 15-24
15-10 Proposed Phase II Monitoring Wells 15-25
15-11 Geologic Cross-Section Beneath Site 15-28
15-12 Estimated Areal Extent of Hypothetical Plumes 15-33
from Four Wells-
15-13 Consideration of Solute Migration Rates in Siting Sampling 15-35
Wells
15-14 Well Locations and Plant Configuration 15-38
15-15 Behavior of Immiscible liquids of Different Densities in a 15-40
Complex Ground-Water Flow Regime
15-16 Site Plan 15-42
15-17 Gas Monitoring Well 15-44
15-18 Facility Map . 15-49
15-19 Uncorrected Migration Distances for 5 and 1.25% Methane 15-51
Concentrations
-------
FIGURES
NUMBER PAGE
15-20 Correction Factors for Landfill Depth Below Grade » 15-52
15-21 Impervious Correction Factors (ICF) for Soil Surface Venting 15-54
Condition Around Landfill
15-22 Landfill Perimeter Gas Collection System-Wells 15-56
15-23 Sampling Station Locations for Surface Water Monitoring 15-58
15-24 Site Plan and Water Sampling Ideations 15-68
15-25 Bioassay Responses to Surface Water Samples 15-75
15-26 Surface Water and Sediment Sample Locations 15-78
15-27 Schematic of Wastewater Holding Impoundment Showing 15-82
Sampling Locations
15-28 Site Map Showing Location of Air Monitoring Sites A and B 15-87
15-29 Site Plan and Locations of Air Monitoring Stations 15-94
15-30 Contour Map of the Lead Concentrations in ppm Around the 15-108
Smelter
15-31 Schematic Diagram of Gas Control System Utilized at Pit 15-111
15-32 Schematic Drawing of Wireline Drill Bit and Reaming Shoe 15-112
15-33 Location of Ground-Water Monitoring Wells 15-115
15-34 Topographic Survey Area and Grid Layout 15-119
15-35 Site Map and Monitoring Well Locations 15-127
15-36 October 1983 Aerial Photo of Land Disposal Facility 15-131
15-37 Aerial Photo Interpretation Code 15-132
15-38 February 1984 Aerial Photo of Land Disposal Facility 15-133
15-39 Facility Plan 15-135
15-40 Generalized Geologic Cross-Section 15-137
15-41 Infrared Aerial Photograph of the Site 15-138
XI
-------
FIGURES
NUMBER PAGE
15-42 Map of the Smelter Site and Associated Tailings Ponds 15-141
15-43 Locations of Copper Leach Plant and Waste Storage Ponds 15-142
15-44 Schematic of Surface Water System 15-146
15-45 Ground-Water Flowlines Based on Measured Water Levels 15-147
15-46 Selected Surface Water Quality Parameters at Key Stations 15-148
15-47 Changes in Sulfate Over Time at Selected Wells Located 15-149
Within the Site
15-48 Field Sketch of Tailings Trench T-3 15-151
15-49 Depth vs Concentration Profiles for Selected Variables 15-152
for Borehole 88A
15-50 Ground Water Level Elevations and Flow Directions in 15-166
Upper Limestone Aquifer
15-51 Topof Lowest Till Contour Map and Location of 15-
Vertical Flow Net
15-52 Vertical Gradient and Flow Line Map 15-
15-53 Vertical Flow Net T-T' 15-
15-54 Sampling Station Locations for Surface Water 15-
Monitoring
15-55 Site Layout: LWDA-2, SDWA-2 and Stream Channel 15-
Identified Through Use of Aerial Photo Interpretation
XII
-------
LIST OF ACRONYMS
AA
Al
ASCS
ASTM
BCF
BOO
CAG
CPF
CBI
CEC
CERCLA
CFR
OR
CM
CMI
CMS
COO
COLIWASA
ONPH
00
DOT
ECD
EM
EP
EPA
FEMA
FID
Foe
FWS
GC
GC/MS
GPR
HEA
HEEP
HPLC
HSWA
HWM
ICP
ID
Kd
Koc
Kow
LEL
MCL
MM5
MS/MS
NFIP
NIOSH
NPDES
OSHA
Atomic Absorption
Soil Adsorption Isotherm Test
Agricultural Stabilization and Conservation Service '
American Society for Testing and Materials
Bioconcentration Factor
Biological Oxygen Demand
EPA Carcinogen Assessment Group
Carcinogen Potency Factor
Confidential Business Information
Cation Exchange Capacity
Comprehensive Environmental Response, Compensation, and
Lability Act
Code of Federal Regulations
Color Infrared
Corrective Measures
Corrective Measures Implementation
Corrective Measures Study
Chemical Oxygen Demand
Composite Liquid Waste Sampler
Dinitrophenyl Hydrazine
Dissolved Oxygen
Department of Transportation
Electron Capture Detector
Electromagnetic
Extraction Procedure
Environmental Protection Agency
Federal Emergency Management Agency
Flame lonization Detector
Fraction organic carbon in soil
U.S. Fish and Wildlife Service
Gas Chromatography
Gas Chromatography/Mass Spectroscopy
Ground Penetrating Radar
Health and Environmental Assessment
Health and Environmental Effects Profile
High Pressure Liquid Chromatography
Hazardous and Solid Waste Amendments (to RCRA)
Hazardous Waste Management
Inductively Coupled (Argon) Plasma
Infrared Detector
Soil/Water Partition Coefficient
Organic Carbon Absorption Coefficient
Octanol/Water Partition Coefficient
Lower Explosive Limit
Maximum Contaminant Level
Modified Method 5
Mass Spectroscopy/Mass Spectroscopy
National Flood Insurance Program
National Institute for Occupational Safety and Health
National Pollutant Discharge Elimination System
Occupational Safety and Health Administration
Kill
-------
LIST OF ACRONYMS (Continued)
OVA
PIO
Ppb
ppm
PUF
PVC
QA/QC
RCRA
RFA
RfO
RFI
RMCL
RSO
SASS
SCBA
SCS
SOP
SWMU
TCLP
TEGO
TOC
TOT
TOX
USGS
USLE
UV
VOST
VSP
WQC
Organic Vapor Analyzer
Photo lonization Detector
Acid Dissociation Constant
parts per billion
parts per million
Polyurethane Foam
Poly vinyl Chloride
Quality Assurance/Quality Control
Resource Conservation and Recovery Act
RCRA Facility Assessment
Reference pose
RCRA Facility Investigation
Recommended Maximum Contaminant Level
Risk Specific Dose
Source Assessment Sampling System
Self Contained Breathing Apparatus
Soil Conservation Service
Standard Operating Procedure
Solid Waste Management Unit
Toxicity Characteristic Leaching Procedure
Technical Enforcement Guidance Document (EPA, 1986)
Total Organic Carbon
Time of travel
Total Organic Halogen
United States Geologic Survey
Universal Soil Loss Equation
Ultraviolet
Volatile Organic Sampling Train
Verticle Seismic Profiling
Water Quality Criteria
XIV
-------
14.0 INTRODUCTION
14.1 Use of Case Studies
This document Volume IV of the RCRA Facility Investigation (RFI) Guidance,
contains case studies selected to illustrate various concepts and procedures in
Volumes I, II. and III. These case studies are provided to explain, through example,
how various tasks can be conducted during RFIs. The case studies also identify some
of the potential problems that can occur if the RFI sampling and analytical programs
are not carefully designed and executed. The case studies, however, should not be
used as the primary source of guidance for RFI program design and conduct.
Instead, Volumes I, II and III should be consulted. The studies do not necessarily
address details specific to individual facilities, and omission of certain RFI tasks
should not be interpreted as an indication that such tasks are unnecessary or of less
significance. Most of the case studies are based on actual sites. In some cases,
existing data have been supplemented with hypothetical data to illustrate a
particular point.
14.2 Organization of Volume IV
Table 14-1 lists the points illustrated and identifies the case studies which
provide information relevant to these points. The following general form was used
as appropriate for each case study:
• Title
• Identification of Points Illustrated
• Introduction/Background
• Facility Description
• Program Design/Data Collection
• Program Results/Data Analysis
• Case Discussion
14-1
-------
TABLE 14-1
SUMMARY OF POINTS ILLUSTRATED
POINTS ILLUSTRATED
CASE STUDY
NUMIER
SOIL
• Us* of soil characteristics to estimate mobility of contaminants in soil
• Effects of degradation in determining the fate of a contaminant in soil
1
2
GROUNDWATER
• Use of split-spoon sampling and organic vapor monitoring to select
screened intervals for ground water monitoring
e Development of a two-phase boring program to investigate ground water
contamination
e Use of basement monitoring to estimate contaminant migration
e Use of mathematical models to determine locations of ground water
monitoring wells
e Monitoring and characterization of ground water contamination when two
liquid phases are present
e Methodology for construction of vertical flow nets
3
4
5
6
7
28
SUBSURFACE GAS
e Design of a phased monitoring program to adequately characterize
subsurface gas migration
• Use of predictive models to estimate extent of subsurface gas migration
8
9
SURFACE WATER
• Use of existing site-specific data to design a surface water monitoring
program
e Use of bioassays and bioaccumulation studies to assess potential biological
effects of off-site contaminant migration
e Use of sediment sampling to indicate off-site contaminant migration via
surface runoff
• Design of a sampling program to account for three-dimensional variations
in contaminant distribution
e Use of dispersion zone concepts in the design of a surface water monitoring
program
10
11
12
13
29
AIR
• Use of dispersion modeling and air monitoring data to estimate downwind
contaminant concentrations
e Design of an upwind/downwind monitoring program when multiple
sources are involved
14
15
SELECTION OF MONITORING CONSTITUENTS
e Use of 40 CFR Part 261 Listing Background Documents in selecting
monitoring constituents
e Consideration of degradation as a factor in identifying monitoring
constituents
16
2
-------
TABLE 14-1
SUMMARY OF POINTS ILLUSTRATED
PAGE TWO
POINTS ILLUSTRATED
CASE STUDY
NUMIER
SAMPLING SCHEMES
• Selection of a sampling scheme that appropriately characterizes soil 17
contamination
e Evaluation of the effectiveness of a sampling scheme using statistical 17
analyses
e Use of release monitoring/leachate collection to characterize wastes when 18
the actual waste stream is inaccessible, as in the case of buried drums
WASTE CHARACTERIZATION
e Correlation of a contaminant release with a specific waste management 19
unit using ground water data
e Use of site topographic information in selecting test boring and monitoring 20
well locations at facilties where large volumes of waste have been disposed
e Use of waste stream information to select indicator parameters and 21
monitoring constituents in a ground water monitoring program and to
reduce the number of Appendix VIII constituents that must be monitored
e Use of information on possible waste reaction products in designing a
ground water monitoirng program 22
AERIAL PHOTOGRAPHY
e Use of aerial photographs to identify actual and potential waste migration 23
routes and areas requiring corrective action
e Identification of a ground water contaminant plume using infrared aerial 24
photography
e Use of historical aerial photographs and facility maps to identify old waste 31
disposal areas and ground-water flow paths
DATA PRESENTATION
e Techniques for presenting data for facility investigation involving
multimedia contamination
25
QUALITY ASSURANCE AND CONTROL
e Use of quality assurance and control and data validation procedures
26
HEALTH AND SAFETY
e Example of a health and safety plan
30
CORRECTIVE MEASURES INCLUDING INTERIM MEASURES
e Use of biodegradation and removal for interim corrective measures
e Corrective action and the implementation of interim corrective measures
2
27
-------
15.0 CASE STUDIES
CASE STUDY 1: USING SOIL CHARACTERISTICS TO ESTIMATE MOBILITY OF
CONTAMINANTS
Point Illustrated
o Information on soil characteristics can be used to estimate the relative
mobility of contaminants in the subsurface environment.
Introduction
•
The relative mobility of contaminants can be estimated using soil
characteristics and aquifer hydraulic characteristics. Although metals do
precipitate at higher concentrations, at the levels encountered in most subsurface
environments, sorptlon is the dominant attenuation prcoess. The degree to which a
metal sorbs onto soil particles depends on the soil pH, the percent clay, the percent
soil organic matter, the presence of particular coatings (e.g., iron, manganese, and
aluminum oxide/hydroxides) and to a lesser extent, the type of clay present. For
organic contaminants, there are several processes which may be important in
predicting their fate in soils. These include sorption, biodegradation, hydrolysis
and, to a lesser extent, volatilization. The sorption of a given organic compound
can be predicted based on its ootanol-water partition coefficient, the percent
organic carbon in the soil, and the grain-size distribution of the soil.
Determining the relative mobility of contaminants can be helpful in selecting
appropriate sampling locations. For example, if wastes containing metals were
present in an impoundment, samples to determine the extent of any downgradient
metal contamination would normally be collected within a short distance of the
impoundment. On the other hand, for fairly mobile waste constituents such as
trichloroethylene (TCE), samples could be taken over a much larger downgradient
distance. The case study presented below illustrates how contaminant mobility can
be estimated.
15-1
-------
Facility Description
A 17 acre toxic waste dump operated in a mountain canyon for 16 years. The
facility received over 32 million gallons of spent acids and caustics in liquid form.
These wastes were placed in evaporation ponds. Other wastes sent to the facility
included solvents and wastes from electroplating operations containing chromium,
lead, mercury and zinc. Pesticides including DOT had been disposed of in one
corner of the site.
Site Description
»
The site was underlain by alluvium and granitic bedrock (Figure 15-1). The
bedrock, as it was later discovered, was fractured to depths of between SO and 100
feet. Ground water occurred in the alluvial deposits at depths of 10 to 30 feet.
Several springs existed in the upgradient portion of the site. A barrier dam was
built across part of the canyon at the downgradient edge of the site in an effort to
control leakage. Because of the extensive fracture system, this barrier was not
effective. Instead, it appears to have brought the ground water table up into the
wastes, and at the same time, pressurized the underlying fracture system, thereby
creating seepage of contaminated water under the dam.
Estimation of Contaminant Mobility
Because of the variety of constituents accepted at this site, an estimate of
their relative mobility was needed prior to designing the remedial investigation.
The first step was to estimate the downgradient seepage velocity using the
following equation:
where
Vg » horizaontal seepage velocity, ft/day
K - hydraulic conductivity, ft/day
I * ground water gradient
P « effective porosity, decimal fraction.
15-2
-------
o
»
?
I
15-3
-------
The hydrogeologic data needed were obtained from existing sit* assessment
reports. The alluvium underlying the site had an average hydraulic conductivity of
0.8 ft/day and an estimated effective porosity of 11 percent. The average ground
water gradient below the site was 0.06. Using the above equation, the seepage
velocity was estimated to be 160 ft/yr. This represents the average velocity at
which a conservative constituent would migrate downgradient along the centerline
of the plume. Examples of such constituents include chloride and bromide. As
shown in Table 15-1, nitrate and sulfate also behave conservatively in many cases.
Due to the. absence of highly weathered* sesquioxide soils* sulfate behaved
conservatively at this site. Using the above seepage velocity, an estimate was
made of the distance a conservative solute would travel in a given time,
T (d « VST).- Limited water quality data were available for 1980. Wastes were first
disposed at this site in 1956. The average extent of plume migration along the
centerline was thus estimated to be 3800 feet.
With respect to metals, additional data were needed to estimate their fate
including soil pH, presence of carbonates, organic ligands, and percent soil organic
matter and clay. At this site, the soil pH varied from less than 3.0 within 400 feet
of the acid ponds to 7.2 at a distance 2000 feet downgradient. As shown in
Figure 15*2, the partition coefficients for metals are dependent on pH and organic
matter content. For example, below a pH of S.6, for the types of soil encountered
at the site, the partition coefficient (Kp) for cadmium is about 10 ml/g. At a pH of
7.2, Kp is about 6500 ml/g (Rai and Zachara, 1985). The relative mobility of
attentuated constituents can be estimated as follows (Mills et aJ., 1985):
VA
where
VA * average velocity of attentuated consitutent along centerline
•
of plume, ft/day
Vg * seepage velocity as defined above, ft/day
R<] * retardation factor (unitless)
and
Rd
15-4
-------
TABLE 15-1
RELATIVE MOBILITY OF SOLUTES
Group
Conservative
.. - _
Slightly Attenuated
Moderately Attenuated
More Strongly
Attenuated
Examples
TOS
CL-
BR-
NO,
SO4*-
B
TCE
Se
As
Benzene
Pb
Hg
Penta-
chlorophenol
Exceptions
•
Reducing conditions
Reducing conditions
and in highly
weathered soils coated
with sesquioxides
Strongly acidic systems
Anaerobic conditions
Master Variables*
v,
V. pH, organic matter
V*
V$, organic matter
V$. pH, Fe hydroxides,
V4 , pH, Fe hydroxides,
VL. organic matter
V$,pH,S042'
v$,pH.cr
V ' organic matter
»•
Variables which strongly influence the fate of the indicated solute groups. Based on data
from Mills ej.aJL, 1985 and Rai and Zachara, 1984.
15-5
-------
100
Nretnt
Adsorption
by Soil
SO
Shift due
to prtsinet
of soil organic
Mtttr
Typical
adsorption
curve for
htavy Mtal
i. on a cltan
silica or
aluminum
slUcatt
surfaca
Typical adsorption
curvt for htavy
natal x. on silica
or aluminum s111catt
surf act coattd
soil organic mattar
pH of the Soil Solution
a) Generalized Heavy Metal Adsorption Curve for Cationic Species
(e.g., CuOH*)
100
Percent
Adsorption
by Soil
50
N
Typical adsorption \
curve for heavy \
metal species, x, .x
on iron hydroxide \
\
\
\
A
N
Shift
•
x due to \
\ presence \
\ of soil \
V organic \
v matter \
pH of the Soil Solution
b) Generalized Heavy Metal Adsorption Curve for Anionic Species
(e.g.,
Figure 15-2. Hypothetical Adsorption Curves for a) Cations and b) Anions
Showing Effect of pH and Organic Matter (Mills et aL, 1985)
15-6
-------
where
Kp » soil-water partition coefficient for solute of concern* ml/g
0B * soil bulk density, g/ml
p « effective soil porosity (decimal friction).
For example* the relative mobility of cadmium at a pH of 7.2 was computed for
this site as shown below:
Rd
VA > 160/100,000 = 0.002 ft/yr.
This estimate was consistent with the field data which indicated that the metals
migrated only until the pH of the contaminated plume was neutralized, a distance
of about 2000 feet. Cadmium concentrations decreased from 1.3 mg/1 at a
distance of 1400 feet from the ponds to below detection (0.1 ug/1) at a distance of
2000 feet.
Estimates of mobility for organic contaminants which sorb onto soil particles '
can be made in an analogous manner. The partition coefficient for organic
constituents can be calculated using the following equation (Mills et aL, 1985):
6500(1.7) - ioofOOO
gp * Koc[0.2(l-f)X3c .
where
Kp * soil-water partition coefficient, ml/g
KOO * organic carbon partition coefficient, ml/g
and
KOC » 0.83 Kow
K0ws octanol-water partition coefficient
f - mass of silt and clav ,fl< , .»
mass of silt, clay and sand - -
= organic fraction of sand (X^G <, 0.01)
3 organic fraction of silt-clay (0 ^ x|c ^ 0.1)
15-7
-------
For example, the solvent triehlorethylene (TCE) has a Kow value of 200. Using the
above equation and aite data (f = 0.1, X£e = 0.001, xfc = 0.01), the partition
coefficient Kp waa estimated to be 0.2 ml/g. The relative mobility of TCE at the
site was then estimated as shown above (R
-------
Sc«l«
i i i
0 800
F««t
Figure 15-3. Schematic Diagram Showing Plumes of Total Dissolved Solids (TDS),
Total Organic Halogens (TOX) and Heavy Metals Downgradient of
Waste Disposal Site
15-9
-------
CASE STUDY 2s ESTIMATION OP DEGRADATION POTENTIAL
OP CONTAMINANTS IN SOIL
Point Illustrated
o Degradation, either chemical or biological, can be an important factor
in determining the fate of a contaminant in soil, and can also be a
factor in identifying constituents to monitor for. The degradation rate
can also be accelerated as a means of conducting interim or definitive
corrective measures.
Introduction'
Degradation of contaminants in the environment can occur through several
mechanisms, and can be a factor in identifying monitoring constituents. Under
natural conditions, these processes are often very slow, but studies have shown that
chemical and biological degradation can be accelerated in the soil by modifying soil
conditions. Parameters such as soil moisture content and redox condition can be
altered to encourage contaminant degradation in soils.
Site Description
The site is situated in an arid region that was used during the 1970s by aerial
applicators of organochlorhie and organophosphate pesticides. The applicators
abandoned the site in 1980 and homes were built in the vicinity. The site can be
divided into three areas based on past use. The most contaminated area, the hot
zone, is a 125 feet by SO feet area at the north end of the site that was used for
mixing* loading, and unloading the pesticides. Soil samples from this area
contained toxaphene, ethyl parathion, and methyl parathion at concentrations up to
15,000 mg/kg, and were clearly above health and environmental criteria. The
present residential area was used as a taxiway and an area to rinse tanks and clean
planes. Soils from this zone were low in parathions but toxaphene concentrations
ranging from 20 to 700 mg/kg were found, and in some cases exceeded health and
environmental criteria. This area is approximately 1.7 acres in size and locatec
immediately south and west of the hot zone. The runway itself was approximately
10 acres in size and to the south of the residential zone. Soil sample results from
the runway area were low for all three pesticides.
15-10
-------
A number of factors influence degradation of organic compounds in soils.
These include:
•
o chemical nature of the compound
o organic matter content of the soil
o soil pH
o oxidation/reduction environment of the soil
o concentrations of the compound.
At the subject site, the soils were low in moisture content, were oxidizing, and
exhibited soil pH values of 6.8 to 8.0. Under such conditions, parathion can be
degraded* slowly by alkali catalyzed hydrolysis reactions. The rate of these
reactions increases with increasing soil pH. Parathion can also be biodegraded to
0,O-Diethyl phosphoric acid. At a nearby site, it was shown that toxaphene will
degrade anaerobically if reducing conditions can be achieved in the soiL It has also
been observed that the loss of toxaphene by volatilization is enhanced by high soil
moisture content. Other data indicated that toxaphene will degrade in the
presence of strong alkali, by dechlorination reactions. This information can be
used in identifying monitoring constituents and in performing interim and definitive
corrective measures.
To test the feasibility of chemically degrading the contaminated soil, in situ.
laboratory bench-scale tests were performed. Two treatments were evaluated,
application of calcium exide (quicklime) and sodium hydroxide (lye). Figure 15-4
shows that the pesticides were degraded by both of these strong alkalis.
Those responsible for the remedial measures felt that the hot zone was too
contaminated for in situ treatment to be effective over reasonable time periods.
The upper 2 feet of soil from this area was excavated and transported to a secure
landfill for disposal. However, the 1.7 acre residential area was treated in situ. To
promote degradation, approximately 200 g/ft2 of sodium hydroxide was applied
using a tractor with a fertilizer-spreading attachment. A plow and disc were used
to mix the sodium hydroxide into the soil to a depth of l.S feet. At 70 days after
the application, concentrations of ethyl parathion had decreased by 76 percent,
methyl parathion by 98 percent, and toxaphene by 45 percent.
15-11
-------
1000
V
4
OAVS
»T*u. Imrl Pirahiofl r
171
ill
f
J 4 t •
OATS
U>«rii«fy Inrt Tm. Tamtam
Figure 15-4.
Results of Laboratory Bench Test for Pesticide Degradation (from
King et al.. 1985)
15-12
-------
Case*Discussion
Knowledge of the properties of a contaminant as well as its environment are
important in assessing the potential for degradation, and this information can be
used to identify monitoring constituents and conduct interim or definitive
corrective measures. It may be possible to alter the site's physical or chemical
characterisitcs to enhance degradation of contaminants. Under appropriate
conditions, in situ treatment of contaminated soils can be an effective corrective
measures method.
King, J.,-T. Tinto, and M. Ridosh. 1985. In Situ Treatment of Pesticide
Contaminated Soils. Proceedings of the National Conference of Management of
Uncontrolled Hazardous Waste Sites. Washington, D.C.
15-13
-------
CASE STUDY 3z USE OF SPLIT-SPOON SAMPLING AND ON-SITE VAPOR
ANALYSIS TO SELECT SOIL SAMPLES AND SCREENED
INTERVALS FOR MONITORING WELLS
Point Illustrated
o HNU and OVA/GC screening provides a relative measure of
contamination by volatile organic*. It can be used to select soil
samples for further analysis and can assist in the selection of screened
intervals for monitoring wells.
Introduction
On-site vapor screening of soil samples during drilling can provide indications
of organic contamination. This information can then be used to identify apparent
hot spots and to select soil samples for detailed chemical analyses. In this manner,
the use of higher powered laboratory methods can be focused in an effective way
on the analysis of samples from critical locations and depths. The vapor analyses
on site can also be helpful in selecting screened intervals for monitoring wells.
Facility Description and History
Manufacturing of plastics and numerous other chemicals has occurred at the
site over the past 30 years.* Some of the major products included cellulose nitrate,
polyvinyl acetate, phenol, formaldehyde, and polyvinyl chloride. The entire site
covers 1,000 acres. The location of the buildings and waste disposal areas are
shown in Figure 15-5.
Three disposal methods are known to have been employed at the site.
Readily combustible materials were incinerated in four burning pits, while non-
combustibles were either disposed of in landfills or in a liquid disposal area. All
on-site disposal operations were terminated in 1970, and monitoring programs have
been implemented to identify contaminants, to defined and monitor ground water
plumes, and to assess the resulting environmental impacts.
15-14
-------
'§
ii
-o
I
15-15
-------
Geologic and Hvdrologic Setting
The site is located in a well-defined glacial valley, adjacent to a river. Three
major units underlie the site - one consisting of sand and gravel outwash deposits;
two* fine-grained lacustrine sands; and three; till. The middle sand unit contains
lenses of silt, clay and thin till. Only the deep till formation appears to be
continuous across the site. A geologic cross-section beneath two of the disposal
areas is shown in Figure 15-6.
The ground-water flow direction at the site is to the northwest. However,
there appears to be a buried stream channel running across the site which strongly
influences the local ground water flow regime (Figure 15-7). Ground water from
the site is thought to discharge to the river. The depth to ground water varies
from 10 to 40 feet.
Sampling Program
As part of the remedial investigation at this site, 33 borings were drilled
using a hollow-stem auger rig. Continuous soil samples were collected using split-
spoon samplers. Samples for laboratory chemical analysis were selected based on
the volatile organic concentrations detected by initial vapor screening of the soil
samples in the field.
This field screening was achieved by placing a portion of each sample core in
a 40 ml glass headspace vial. An aliquot of gas was extracted from the vial and
injected directly into a portable OVA gas ehromatograph (OVA/GC). The
chromatograph was equipped with a flame ionization detector to identify
hydrocarbons. Each sample was also screened using an HNU photoionization
detector because of its sensitivity to aromatic hydrocarbons, particularly benzene,
toluene and the xylenes. Following completion of drilling, gamma logs were run on
all boreholes.
An example of the vapor screening results (HNU and OVA/GC) and geological
and gamma logs for one of the boreholes are shown in Figure 15-8. The data shown
demonstrate the differential sensitivity of the HNU and OVA/GC detectors.
Because the OVA/GC is more sensitive to the organics of interest (allphatics),
15-16
-------
8
I
~1 1 1 I I I
I S 3 2 ! ! ? ?
" -* - tu
15-17
-------
-------
15-19
-------
i
o
i
o
2
s
f
!!
i
E
8
H
CO
10
15-20
-------
these results were used to select samples for detailed chemical analysis in the
laboratory. As shown in Figure 15-8, samples in zones with OVA/GC readings of
390 ppm (45 feet depth), 407 ppm (65 feet depth), and 96 ppm (85 feet depth) were
selected. In the laboratory, samples were first analyzed for total organic carbon
(TOG). The ten samples with the highest TOG levels were then analyzed for
purgeable organics using EPA Method 50-30 and ertractable organics using EPA
Method 82-50 (U.S. EPA, 1982 - Test Methods for Evaluating Solid Waste, SW 846).
The OVA/GC results were also used to select well screen intervals.
Examination of the data in Figure 15-8 stfows that the highest levels of volatile
organics (by OVA/GC) were found at a depth of 65 feet. In addition, the gamma
and geologic logs indicated that the permeable medium at that depth was coarse
sand which would be a suitable location for the placement of a well screen. Thus, a
5 foot stainless steel screen was set over the depth interval from 62 to 67 feet.
Case Discussion
This sampling program incorporated field techniques that detect the presence
of volatile organics and allow on-site, rapid identification of likely contaminant
"hot spots" for detailed laboratory anaysis and to select depths for monitoring well
screens.
15-21
-------
CASE STUDY 4: CONDUCTING SITE INVESTIGATIONS IN TWO PHASES
Points Illustrated
o When ground water contamination is known or suspected at a site, a set
of initial borings is typically made (Phase I) to determine site
hydrogeologic characteristics and to identify areas of soil and ground
water contamination (Phase 0.
o These findings are then used to select well locations to fully delineate
the extent of contamination during a second phase of the investigation
(Phase II).
Introduction
To identify the extent of ground water contamination in an efficient manner,
information is needed on the ground water flow regime. Phase I investigations
typically focus on determining site geologic characteristics and ground water flow
directions and velocities. Waste sources are also identified. The Phase I results
are then used in planning the Phase II investigation to determine the extent of
contamination and to refine estimated rates.of contaminant migration.
Facility and Site Description
Descriptions of the facility and site geologic characteristics were included in
Case Study 3.
Sampling Program
The Phase I sampling program included geophysical surveys, water level
monitoring, soil sampling, and ground water quality sampling. Three seismic
refraction lines were run to estimate the depth to the top of the deep till. The top
of the till was found to occur at a depth of 70 to 120 feet over most of the site.
Available historical data indicated that the general ground water flow
direction was to the northwest across the site. The ground water was thought to
discharge to the river. This information and historical drawings and maps of known
disposal areas were used to locate the Phase I borings (see Figure 15-5 in Case
15-22
-------
Study 3). One well (MW4) was located on the suspected upgradient side of the site.
The other wells were located near waste sources to determine which sources
appeared to be contributing contaminants to the ground water. For example, two
wells (MW6 and 7) were located immediately downgradient of solid waste disposal
area f 2. To determine the presence of vertical gradients, three two-well clusters
were drilled—each with one well screened just below the water table and a second
well screened considerably below that at the base of the till.
The results of the Phase I investigation indicated that all the wells contained
solvents. Thus, investigations of the waste sources and contaminant plumes had to
be continued in Phase II. The highest solvent concentrations were found in wells
located near the liquid waste disposal area where downward vertical gradients were
present. The contaminants had migrated down to depths of 75 feet in this portion
of the site. The Phase I data confirmed the general northwest ground water flow
direction but showed a complex flow pattern near the buried stream channel. A
second concern was whether observed lenses of fine-grained till under the site were
producing zones of perched water which could be contaminated.
Based on the Phase I results, a Phase II monitoring program was designed to
determine the extent of contamination around the major disposal sites. Typically,
2 soil borings were installed - 1 up and 1 downgradient of the waste source.
Because of the high solvent concentrations observed in the wells downgradient of
the liquid disposal area, a more intensive field investigation of this area was
included in Phase II. Instead of 2 borings per waste source at the liquid disposal
area, 11 soil borings and 5 new monitoring wells were drilled. This represented
one-third of the total effort for the entire 1,000 acre site. The total number of
Phase n soil borings was 33 (Figure 15-9) and the total number of Phase II wells was
15 (Figure 15-10). The Phase II data indicated that most of the solvent
contamination originated from the liquid disposal area and not from solid waste
disposal area 11 which is located upgradient of the liquid disposal area. The phase
n data did identify PCBs from solid waste disposal area 11 but not from any of the
other sources. This was consistent with site records indicating that transformers
had been disposed at this site.
15-23
-------
rS
J
1
UJ
I
tn
£
15-24
-------
- s §
fS 1 I
I
s
i
15-25
-------
Case Discussion
Investigation of a large complex site is best conducted sequentially. Basic
information is needed on site geologic characteristics and ground water seepage
velocities and directions to appropriately locate wells for determining the extent
of contamination. Thus, the initial installation of a limited number of exploratory
borings and wells can provide the data needed to design a complete and effective
investigation. Results from the latter can then be used to determine the need for
remedial action and to evaluate alternative remediation methods.
15-26
-------
CASE STUDY 5: MONITORING BASEMENT SEEPAGE
Point Illustrated
o Basement monitoring can be used to estimate the extent of
contaminant migration.
Introduction
Leachate produced in a landfill can -be transported downgradient in ground
water by advection and dispersion. Shallow ground water may surface and seep
into basements.
Site Description
A channel, originally constructed as part of a hydroelectric power generation
system, was used as a disposal site for a variety of chemical wastes from the 1920s
through the 1950s. More than 21,000 tons of waste were dumped in and around the
site before its closure in 1952. After closure, homes and a school were constructed
on and around the site. In the 1960s, residents began complaining of odors and
residues. During the 1970s, the local water table rose, and contaminated ground
water seeped into nearby basements.
Geologic and Hvdrologic Setting
Figure 15-11 shows a cross-section of the site. The site has both a shallow
and a deep aquifer. The shallow aquifer consists of approximately 5 feet of
interbedded layers of silt and fine sands overlying beds of clay and glacial till. The
deeper aquifer is a fractured dolomite bedrock overlying a relatively impermeable
shale. Travel times from the shallow to the deeper aquifer are relatively long.
Contamination has occurred in the shallow aquifer because of the "bathtub effect".
The impermeable channel filled because of infiltration, and leachate spilled over
the channel sides. The leachate contaminated the shallow ground water and was
transported laterally in this system.
15-27
-------
I
i
i
i
i
• •
«
OQ
S
I
U
e>
15-28
-------
Sampling Program
The houses surrounding the channel were grouped into three sets (upgradient,
downgradient, and on-site) based on preliminary data on the underlying strata and
ground water flow directions. Four houses from each group were selected for
sampling for a total of 12 houses. Samples of water and sediments were collected
from the sump pump wells in each basement. Water samples were collected at
times when the sump pumps were running and 24 hours after pumping had ceased.
Water and sediment samples were analyzed for purgeable and extractable organics.
Benzene, carbon tetrachloride, chloroform, and trichloroethylene (TCE) were found
in the water samples. Water samples taken while the sump pumps were running had
higher concentrations of volatile organics. Sediment samples contained PCBs and
dioxin, possible due to cosolvation. Relatively immobile organics can become
dissolved in another more mobile solvent. The mobile solvent containing traces of
other organics can be advected along with the water. This process (cosolvation) is
one facet of enhanced transport which has recently been proposed as a possible
mechanism for the observed mobility of otherwise immobile organics. Samples of
water and sediments from storm drains were also collected and analyzed to
determine if discharges from the sumps to the storm drains were a significant
source of organics in the storm runoff.
In addition to determining water quality, indoor and outdoor air quality was
measured in the basements at each house. Tenax and polyurethane foam tubes
were placed in air monitoring systems in each basement to measure 12-hour
average concentrations of volatile organics (e.g., carbon tetrachloride, benzene,
TCE) and semi-volatile organics (e.g., pesticides). Volatile organics were present
in the indoor air samples but semi-volatile organics were not detected. The highest
volatile organic concentrations were observed during the time when the sump
pumps were operating.
Case Discussion
At sites where hydrogeologic factors favor shallow lateral ground water flow,
initial site characterization may involve sampling of basements. Results from such
an initial site characterization can provide information on contaminant migration
15-29
-------
which can b. ua«d to n. d«ip, .„„ jrapl.m«nt.tion of detliltd
water monitoring programs.
tbove
of 4 „„„„., of hom^ A ^^ of mon8rBJ w€Uj ^
l»UU.d to «puc. «,. „„.„.,„ maf nafUnt J!UJ< mt |hii|ow ^^ ^
pumo«d tnd trettxl to urat conttmlnant migration.
15-JO
-------
CASE STUDY 8: USE OF PREDICTIVE MODELS TO SELECT LOCATIONS FOR
GROUND WATER MONITORING WELLS
Point Illustrated
o Simple mathematical models can be used to estimate the longitudinal
and transverse spread of a contaminant plume. Wells can then be
located in areas expected to have elevated contaminant concentrations
and in areas thought to be both up and downgradient of the plume.
Introduction
The use of mathematical models to estimate the migration of contaminants
can be helpful for several reasons, including: 1) fewer wells may be needed to
delineate a contaminant plume, and 2) wells can be rationally located in an attempt
to determine the maximum concentrations in a plume, its furthest extent, and
locations where concentrations should be at background levels.
Facility Description
The site was an electronics manufacturing plant that had been in operation
for 20 yean. Four large diameter, rock-filled "dry wells" had been used to dispose
of solvents and process wastes. These disposal units were between 35 and 60 feet
deep. Depth to ground water was over 460 feet. Disposal Units 1 and 2 had
received paint wastes and solvents, including trichloroethylene (TCE) and
tetrachloroethylene, between 1964 and 1979. Disposal Units 3 and 4 had been used
to dispose of plating solutions and spent acids between 1971 and 1977. These
solutions contained copper, chromium, nickel, lead and tin. All the disposal units
were closed in 1982. Exact quantities of wastes disposed are not known.
Geologic and Hvdrologic Setting
The site is located in a large alluvial basin in an arid region. The basin
alluvium is over 1,000 ft thick and consists of an upper sand and gravel unit, a
middle silty-clay unit, and a lower sand and gravel unit. Granitic bedrock underlies
the unconsolidated formations. Priot to large withdrawals of ground water, the
15-31
-------
upper unit had been saturated. At present, the silty-olay unit acts as an aquitard so
that water beneath it is under confined conditions. The piezometric surface is now
350 ft below the land surface. In addition to a drop in water level elevations, the
ground water flow direction has changed over the yean from east to north in
response to changing pumping regimes. Estimated horizontal seepage velocities
have varied from 10 to 40 feet/year.
Site Investigation
In 1982, city water officials discovered TCE in water samples from wells
located within 3 miles of the site. On its own initiative, the site owner began a
»
pre-remedial investigation, and then later a remedial investigation, to determine
whether its site could be a source of the TCE. The pre-remedial investigation
provides an example of how simple models can be used to determine well locations.
The pre-remedial investigation included sampling nearby wells and drilling a single
deep sampling well (over SOO feet deep).
Original plans called for locating the deep monitoring well between the waste
disposal units in an attempt to determine whether solutes had contaminated the
underlying ground water. However, site constraints including an overhead power
transmission line, underground power lines and major manufacturing buildings,
necessitated that the monitoring well site be moved. The next step was to
determine an appropriate location for this well. Because of the changing ground
water flow direction at this site, it was decided to use a simple mathematical
model to predict the areal extent of contamination from the disposal units. The
results would then be used in selecting a new location for the deep monitoring well.
Data were collected to determine historical ground water gradients, pumping
histories, and aquifer hydraulic characteristics (permeability, porosity). Following
data collection, a vector analysis model "the method of Mido" (1981) was used to
predict plume evolution. The results showed that the major plume migration was
to the north (Figure 15-12). Thus, the well was located north of the disposal units
at a distance of 60 feet from Unit 4.
15-32
-------
Final Site of Deep
Monitoring Well'
DISPOSAL UNIT «4
DISPOSAL UNIT t3
Original Planned
Deep Monitoring
Well Location
DISPOSAL UNIT f2
DISPOSAL UNIT #1
Scale
r
0
100
BUILDING 2000
Feet
BUILDING 1000
Figure 15-12. Estimated Areal Extent of Hypothetical Plumes from Four Wells
15-33
-------
Case Discussion
Use of a model to predict potential plume migration at this site provided a
means of evaluating the long-term consequences of changing ground water flow
directions and velocities. Thus, the pre-remedial investigation deep monitoring
well could be sited in the direction of net plume displacement, rather than at a
location which might have had a low probability of intercepting contaminated
ground water. A concentration below the detection limits from a well located
beyond the expected plume boundaries would have been inconclusive (for example*
see Figure 15-13). However, the deep monitoring well was located close to the
disposal units and in the direction of plume migration.. Additional wells are now
being planned for the full-scale remedial investigation.
Reference
Mido, K.W. 1981. An economical approach to determining extent of ground water
contamination and formulating a contaminant removal plan. Ground Water,
VoL 19, No. 1, pp. 41-47.
15-34
-------
'SAMPLING WELL
WASTE SOURCE
YEARLY INCREMENTS OF WATER AND
CONSERVATIVE SOLUTE MOVEMENT
Figure 15-13. Consideration of Solute Migration Rates in Siting Sampling Wells.
If a monitoring well is sited farther downgradient than solutes could
have traveled in the time since disposal, low concentrations in the
well would certainly not prove that ground water contamination had
not or was not occurring. Prior to locating a well, seepage
velocities should be estimated (Vss KI/P where Vs » seepage
velocity for conservative solutes, K = hydraulic conductivity, I =
ground water gradient, and p = effective porosity). Using these
estimates, and the age of the disposal unit, T, an approximate
migration distance, D, can be computed (D * T/Vj) for conservative
solutes associated with the waste. For soil interactive solutes,
migration distances will be less. • Methods for estimating these
distances are given by Mills et at. (1985). By properly siting
monitoring wells, one can avoid unnecessary expense or
embarrassment.
15-35
-------
CASE STUDY 7: MONITORING AND CHARACTERIZING GROUND WATER
CONTAMINATION WHEN TWO LIQUID PHASES ARE
PRESENT
t
Point Illustrated
o Monitoring and characterizing ground water contamination when two or
more liquid phases are present requires knowledge of the physical and
chemical properties of each phase.
Introduction
Increasingly, ground water supplies are becoming contaminated with
immiscible organic liquids. Organic liquids such as PCB-contaminated transformer
oils, petrochemical solvents, and motor fuels, because of their nature, often form a
second liquid phase. This separate liquid, in either the vadose or saturated ground
water zone, represents a problem in multiphase flow. It is necessary to understand
how these separate phases behave when designing monitoring and sampling
programs for sites contaminated with such liquids. Techniques commonly used for
single-phase flow systems may not be appropriate.
Site Description
The facility is a transformer manufacturing plant which experienced a major
discharge of polychlorinated biphenyls (PCBs) and trichlorinated benzenes (TCBs).
The discharge resulted from a break in a buried pipeline, but surface spillage may
have also occurred during production. The volume and duration of the subsurface
discharge is not known; neither is the quantity released by above ground spillage.
Geological and Hvdrologic Setting
The site is underlain by 10 feet of fill over lacustrine clay which varies in
thickness from 20 to 30 feet. Fractures with opening of approximately 0.1 cm have
been observed in the clay. Below the clay lies a thin silt layer. Below that is a 40
to 60 foot thick layer of glacial till composed of fine sand near the top, and gravel,
sand, and silt below.
15-36
-------
Perched water about 3 feet deep flows laterally in the fill. The permanent
water table, located in the till, is partially confined. Piezometric levels in this
latter system are between 25 and 30 feet below the land surface.
Sampling Program
Over 1000 soil samples were taken as part of the site investigation. A mobile
atmospheric pressure chemical ionization mass spectrophotometer (APCI/MS) was
employed for rapid, on-site characterization of soil samples. This instrument can
detect PCBs down to a minimum concentration of 100 mg/kg. About 20 percent of
the PCB analyses were replicated by conventional gas chromatography.
Granular dry materials were sampled from an auger with care taken in
cleaning sampling equipment to avoid cross-contamination. In taking samples from
the clay, special effort was made to sample the surfaces of obvious fractures. This
was done to maximize the changes of detection of PCBs in largely uncontaminated
soil. Due to dilution, large bulk samples can prevent the detection of contaminant
migration through fractures in low permeability soils.
Vertically, the soil sampling program showed PCBs to be distributed in a non-
homogeneous pattern within the clay zone. Concentrations of PCBs greater than
500 mg/kg PCBs were detected. The lateral spreading of PCBs throughout the fill
was much more extensive than the vertical movement. This could be due to the
nature of the discharge/spillage, pressure from the broken pipe, or the fact that
the fill is more permeable than the clay. The PCBs appear to have formed a layer
along the fill/clay interface. Movement of PCBs more than 300 feet laterally from
the original spill site has been confirmed.
Based on the soil sampling results, 12 well locations (Figure 15-14) were
chosen to further characterize the site. Four boreholes were drilled into the till
aquifer. One well, 686-B, was placed upgradient of the spill site with a screened
interval between depths of 45 and 50 feet. The three downgradient wells in the till
aquifer were screened over different intervals to increase the possibility of
detecting a separate organic liquid layer. The screened intervals used were at
depths 45 to 50 feet (well 686-A), 50 to 55 feet (well 686-C), and 55 to 60 feet
15-37
-------
08
07
04
06
6S6-C
• • 686-0
686-A 02
PARKING LOT
pipeline
MANUFACTURING
PLANT
• 686-8
OFFICES
direction of
ground wattr
flow
N
• deep well locations
o shallow welt locations
Figure 15-14. Well Locations and Plant Configuration
15-38
-------
(well 686-D). Eight wells were also placed in the fill to monitor the perched water
(Figure 15-14). The fill is approximately 10 feet deep and a layer of PCBs was
suspected at the fill/clay interface. The depth of the perched water fluctuates
between 7 and 8 feet. Six of the eight wells in the fill, 1, 3, 4, 6, 7, and 8, are
screened from 7 to 10 feet. Samples from wells 1, 6, 4, and 7 showed PCB levels
much higher than the solubility limits. The sampling results suggest that two
separate liquid layers exist at these locations and that the liquids are being mixed
during sampling. Wells 2 and 5 were screened from S to 8 feet to determine if a
floating liquid layer was present. Again, samples having concentrations far in
excess of solubility limits indicated the existence of a layer of organic liquid.
Case Discussion
Ground water systems contaminated with immiscible liquids require special
attention. Well screen intervals should be placed to intercept flow along
boundaries between soil layers of differing permeabilities and at water table
surfaces. Sampling results must also be interpreted properly. Samples showing
contaminant concentrations far in excess of solubility limits may indicate that two
layers of different liquids are being pumped and mixed.
Finally, Figure 15-15 is offered as an illustration of the types of complexity
which can be encountered with immiscible liquids having densities both greater
than and less than water.
15-39
-------
LIGHT POLLUTANT
/, ' , ,'» ' 'I CMOUNO WATfg FLOW
' .' ' i . . . .' •
Figure 15-15. Behavior of Immiscible Liquids of Different Densities in a Complex
Ground Water Flow Regime
15-40
-------
CASE STUDY 8: PERFORMING A SUBSURFACE GAS INVESTIGATION
Points Illustrated
o Design of a phased monitoring program to adequately characterize the
extent and nature of a subsurface gas release.
o The use of ambient air and basement monitoring to supplement
monitoring well data.
o The importance of subsurface characterization prior to design of a
monitoring network.
Introduction
Gases produced in a landfill will migrate through the path of least resistance.
Subsurface* lateral migration of landfill gas can occur due to natural and man-
made barriers to vertical gas migration, such as impermeable overlying soil layers,
frozen soil, or surface water. Installation of a gas-monitoring well netweork, in
conjunction with sampling in buildings in the area, can be used to determine the
need for corrective measures.
Facility Description
*
The unit in question is a landfill covering approximately 140 acres and
bordered by a river on one side and a floodwall on the other. Beyond the floodwail
lies a residential area (Figure 15-16). Several factors contribute to the subsurface
gas migration problem at this landfill. The site reportedly received large
quantities of organic wastes, which, when decomposed in the absence of air,
produce methane and carbon dioxide gases. The presence of "tight", low
permeability soils at the ground surface (12 feet of clayey silt at the surface
grading to coarse sand and gravel at a depth of 55 feet) in the residential area
combined with a rapidly rising water table below the landfill due to increased
infiltration, restrict the vertical area available for gas migration and encourage
lateral movement.
15-41
-------
L
QQ
i
u»
15-42
-------
Investigation of the gas migration began when foul odors and explosive levels
of methane (5 to 15 percent by volume in air) were discovered in the basement of a
home approximately 200 feet from the landfill. Residents in the area were
evacuated, a sampling network was installed* and monitoring was conducted.
Sampling Program
The sampling was conducted in four phases* an initial screening phase and a
more detailed three-phase sampling program. The monitoring network for the
initial screening phase consisted of four wells (Wl through W4) aligned
perpendicular to the long axis of the landfill, in the direction of (and extending
beyond) the house where the gas was initially detected (Figure 15-16). The wells
were drilled to an approximate depth of 30 feet below the land surface with the
farthest well located about 1000 feet from the landfill boundary. These wells were
sampled twice a day for a month. Samples were analyzed for methane and
combustible hydrocarbons. The results of this initial monitoring showed average
methane levels to be highest at the monitoring well located closest to the landfill
(30 percent by volume), and roughly grading to below the detection limit at the
well farthest from the landfill.
Grab and composite ambient air samples were also taken at the landfill and
around houses in the neighborhood where gas was detected during the initial
monitoring phase. These samples were analyzed for methane and other
combustible hydrocarbons. No gases were detected above normal background
levels in any of these above ground samples.
The next phase of monitoring (Phase I of the detailed sampling) involved the
installation of 14 new gas monitoring wells (1-1 through 1-14 in Figure 15*16). Most
of these were placed in a line 250 feet from and parallel to the langitudinal axis of
the landfill. Seven of these wells were drilled to an average depth of 55 feet, at
least 5 feet below the water table so that ground water levels could be monitored.
The other seven wells averaged 30 feet and did not intercept ground water. As
shown in Figure 15-17, each well consists of three separate gas monitoring probes
at evenly spaced depth intervals. Each probe was packed in gravel to allow gas to
collect in its vicinity. Clay plugs were installed between each probe interval and
15-43
-------
CAST IRON COVER SET IN CONCRETE
GROUND SURFACE.
VALVE
PROBE A
1/4" DIAMETER
POLYETHYLENE
TUBING
PROBE B
•LEGEND
NATIVE SOIL
BACKFILL
BENTONITE PLUG
PEA GRAVEL
VALVE E
PROBE A
PROBE B
2" DIAMETER
PVC PIPE
PROBE C
2" DIAMETER PVC
WELL SCREEN
PROBE C
Figure 15-17. Gu Monitoring Well
15-44
-------
between the top probe and the surface to minimize vertical movement of gas in the
well. After two months of monitoring the well headspace twice monthly, concern
over the high levels of methane that were being measured prompted an expansion
of the monitoring well system.
The Phase II monitoring network involved another 14 wells (II-1 through 11-14)
installed to a depth of 6 feet along three radial lines from the landfill. These wells
were monitored twice monthly with the Phase I wells. Methane was not detected
at these wells because they were not deep enough to penetrate the clayey silt layer
which in this area extended to a depth of 12 feet below the surface. Had adequate
boring logs been compiled prior to the placement of these wells* the time and
money involved in their installation and sampling could have been saved.
Detailed soil boring logs were compiled during the installation of the Phase ffi
wells (III-l through III-8 in Figure 15-16). These wells were drilled to ground water,
averaging 55 feet in depth, were located in the vicinity of the Phase II wells, and
were constructed in the same manner as the Phase I wells, with three gas probes
placed in each well. The Phase III wells were located from 510 to 900 feet from the
landfill. These wells were monitored twice a month for two months concurrently
with the Phase I wells. Methane levels at all but two Phase in wells (which are
located along the same radial line) exhibited explosive concentrations, ranging up
to 67 percent by volume in air. These high concentrations of gas prompted another
round of sampling of homes in the vicinity of wells exhibiting high methane
concentrations.
Methane and combustible hydrocarbons were measured in basements, crawl
spaces, and living areas of 28 homes adjacent to the landfill. All proved to be well
below the lower explosive limit of methane.
Wells were then selected based upon proximity to houses exhibiting the
highest levels of combustible gases, and samples to determine gas composition and
concentration. The proportions of constituents in the collected gas was similar in
all samples analyzed, and concentrations decreased with increasing distance from
the landfill.
15-45
-------
Ambient air sampling for organic gases at the landfill and in the residential
area was also performed at this time and showed low levels of several organic
compounds. Air samples collected in houses near the landfill showed the presence
of two of the gas components measured in the test wells (methane and ethane).
The gas migration hazard had been sufficiently characterized so that a plan
for corrective measures could be developed. This involved the installation of 31
gas extraction wells which were located along a line between the landfill and the
residential areas, and a blower system to "pump" the gas out of these extraction
weUs.
Results
The monitoring program implemented for this case was, for the most part,
effective in characterizing the extent and concentrations of subsurface gas
contamination. The four initial monitoring wells verified that the landfill was the
source of contamination. Phase I monitoring confirmed that the high levels of
methane were present at all depths monitored and along the entire length of the
landfill, The horizontal location of the Phase II wells, in lines radiating from the
landfill, was appropriate, although the lack of subsurface characterization rendered
them useless. Phase III sampling established the vertical and lateral extent of
subsurface contamination into the residential area.
•
Throughout the study, ambient air sampling as well as monitoring of homes in
the area of concern provided adequate safety control, as well as an additional
indication of potential migration of landfill-generated gases.
Case Discussion
*
Subsurface gas migration can occur when atmospheric ventilation of gases
generated in a landfill is insufficient. The gas produced migrates along the paths
of least resistance. Conditions restricting release to the atmosphere such as
saturated or tight surficial soils may force the gas to move laterally over
considerable distances.
15-46
-------
This case was selected an an illustration of a phased approach to monitoring a
subsurface gas release. The results of one phase of monitoring were incorporated
into the design of the next phase throughout the study. Monitoring was performed
at discrete vertical levels below the surface and at distances from the landfill that
were adequate to confirm the extent of the contaminant plume.
The study also illustrates the importance of characterizing subsurface
conditions prior to installing monitoring wells. Fourteen unusable wells were
installed and then monitored for two months because of insufficient preliminary
soil (stratigraphic) characterization.
The "use of ambient and basement monitoring for gas to supplement
monitoring well data is also noted in this case study. The location of new wells can
be based in part on readings from these sources.
15-47
-------
CASE STUDY 9: USE OF THE SUBSURFACE GAS MODEL IN ESTIMATING GAS
MIGRATION AND DEVELOPING MONITORING PROGRAMS
Point Illustrated
o Predictive models can be used to estimate the extent of fas migration
from a suspected subsurface source. This information can be used to
estimate human exposure and to determine appropriate locations for
monitoring wells and gas collection systems.
Introduction
*
Methane is a common landfill gas and is often used as an indicator of landfill
gas migration. The subsurface methane predictive model, described in Volume III,
Appendix F of this document, will yield a methane concentration contour map and
predict the distance that methane will migrate. The model consists of a series of
charts developed by imposing a set of simplifying assumptions on a general
methane migration computer model.
A methane migration distance prediction chart is used to find a preliminary
migration distance based on the age of the site and the soil type. The remaining
charts are used to find correction factors which are in turn used to adjust the
migration distance. These factors are based upon site characteristics, e.g., depth
of the waste.
Facility Description
The unit is located on a 583-acre site in a suburb of a major metropolitan
area. Figure 15-18 shows the site layout. The landfill itself occupies 290 acres.
140 acres of the landfill were used for the disposal of hazardous wastes. B
hazardous and nonhazardous wastes were disposed at the site from 1968 to 19e'
Hazardous waste disposal ended in 1984. The disposal of sewage treatment sludges
and municipal refuse continues. As seen in Figure 15-18, residential development
has taken place with houses now bordering the facility to the south. A population
of 30,000 to 40,000 people reside within a mile radius of the landfill center.
15-48
-------
Sealt HewM
Laboratory,
Truck Sc«lt»
LAKBF1U
VtU. LOCATION NAT
MCt Seal* 1'iUJO1
Figure 15-18. Facility Map
15-49
-------
The unit is a V-shaped fill overlying sediment and bedrock. The rock type is a
poorly consolidated, fractured sandy silt offering no lithologic barrier to gas
migration. The shape of the water table has not been established. Also unknown
are the possible effects of local, permeable formations such as sand lenses, faults,
etc.
The warm climate at the site encourages rapid degradation of organic wastes
and therefore rapid gas production. Site characteristics suggest that vertical gas
migration is not hindered. However, the compaction of the fill cover by truck
traffic combined with the rapid production of gas has forced lateral migration
through the fractured sandy silt.
Applying the Subsurface Methane Predictive Model
The subsurface methane predictive model allows the development of a
subsurface methane concentration contour map. The model predicts the distance
methane will migrate from a unit based on its age, depth, soil type, and
environmental factors. A contour map for two different methane concentrations, 5
and 1.25 percent, is predicted. The likelihood of human exposure can be estimated
from the location of the contours with respect to on site and off site structures.
Application of the model involves three steps. The first step is the prediction
of gas migration distances, based on the age of the landfill and the local soil type.
The unit of interest is 18 years old and has sandy soils. Figure 15-19 shows the
uncorrected methane migration distances for various soils over time. From
Figure 15-19, the uncorrected migration distances for the subject site are 165 feet
and 255 feet for 5 and 1.25 percent methane concentrations, respectively.
The second step in applying the model involves the application of a correction
factor to the migration distances based on waste depth. The deeper the waste, the
greater the opportunity for subsurface migration. Figure 15-20 is used to find the
correction factors for depth. For the subject waste unit the depth is 25 feet, which
corresponds to a correction factor of 1.0 for both concentrations.
15-50
-------
I
«ri
•I
#
10
«n
s
s **
o B
| I
& o
o
V
£
&
Ok
MOIiTMOlN
15-51
-------
.^___^
1
s
:'*
2:
t
* f
?§E
!
i
a
v
Q
I
o
«*
I
u
e*
u»
£
5.
15-52
-------
The final step in applying the model is the correction of migration distances
based on surface venting conditions. The following equation is used to calculate
the venting correction factor, ACF:
ACF = [(ICF-l)(fraction of site which is impermeable)] + 1 (1)
The impervious correction factor, ICF, is obtained from Figure 15-21. In the above
equation, ICF is adjusted to account for the fraction of time the solid is saturated
or frozen and the fraction of the land area that is impermeable due to natural or
man-made barriers. If corrections for both time and area are required, the
fractions are additive. From Figure 15-21, the ICF for a unit 18 yean old and 25
feet deep'is 2.4. Site charcteristics together with weather conditions indicate a
value of 0.4 for the fraction of impermeable area. Substituting these values into
equation 1 yield an adjusted correction factor of:
ACF = [(2.4-1X0.4)] + 1 = 1.56.
Results
Table 15-2 summarizes the results from steps one through three of the model
application. The predicted migration distances for methane are found by
multiplying the uncorrected distance from step one by the correction factors from
steps two and three. The predicted distances of travel for methane are 255 feet
and 395 feet for 5 and 1.25 percent concentrations, respectively.
Table 15-2
MODEL RESULTS
Methane
Concentration
(percent)
5
1.25
Uncorrected
Distance
(feet)
165
255
Correction
for Depth
1.0
1.0
Correction
for Venting
1.56
1.56
Corrected
Distance
(feet)
255
395
15-53
-------
I
o
» ?
I 3
U
il
7 e
9 o
U
•> O
!
6
WOU9IVM09
15-54
-------
Case Discussion
Figure 15-22 is a methane concentration contour map developed from the
predicted travel distances. The map indicates that the possibility of human
exposure to landfill gas is high. Landfill gas is known to be present and well
drilling operations at the landfill have caused minor explosions. The monitoring
wells along the facility perimeter and testing in nearby homes indicate that gas has
migrated off site. The contour for both the 5 percent and 1.25 percent methane
encloses homes evacuated because of gas accumulation. Measures have been taken
to mitigate the immediate problems and the landfill operators have installed
additional gas collection wells and extended the monitoring system.
15-55
-------
36
E
o
JU
"o
O
8
V
*<
at
E
•c
41
a.
15-56
-------
CASE STUDY 10: DESIGN OF A SURFACE WATER MONITORING PROGRAM
Point Illustrated
o When designing a surface water monitoring program, site-specific
sediment and suspended solids information should be considered.
Introduction
Designing a surface water monitoring program to determine the extent of
contamination involves identifying the potential waste sources, the contaminants
likely to -be present in each waste stream, and the flow paths by which the
contaminants could reach surface waters. The fate of the contaminants once they
reach the surface water must also be considered when selecting sampling stations
and parameters to be measured. The example described here illustrates the design
of a monitoring program for a river system.
Facility Description
A facility which processed zinc, copper and precious metals from ores
operated along a river for five yean. The plant was closed after being cited for
repeated fish kills which were reportedly due to failures of a tailings pond dike. At
present, the site is covered with tailings containing high concentrations of copper,
zinc, cadmium, arsenic and lead. There is no longer a tailings pond.
Site Setting
The site is located on coarse colluvium (hill-slope deposits of weathered
bedrock) and fine-grained alluvium. These deposits are typically SO feet thick.
Metamorphic rock (phyllite) underlies the unconsolidated materials. Ground water
moves laterally in the gravel formations from the steep valley walls toward the
river.
The site is about 400 feet from the river. Two drainage ditches cross the
lower portion of the site and merge prior to leaving the site. The ditch carries the
combined flow and discharges directly into the river (Figure 15-23). No other
tributaries enter the river within 2 miles of this location.
15-57
-------
Site Operation*
—. Orainag* Orteh
• SampMng Suflon
N
\
Scale
I
o
Figure 15-23. Sampling Station Locations for Surface Water Monitoring
15-58
-------
Sampling Program
A surface water monitoring program was designed as part of the Phase I
remedial investigation to determine the extent of contamination in the river.
Existing data from a reconnaissance visit had shown high concentrations of metals
in the drainage ditch sediments (e.g., 5,170 mg/kg Cu and 11,500 mg/kg Zn).
Ground water data from the plant's well showed detectable concentrations of Cu
(7 yg/1) and Zn (54 ug/1). The ground water concentrations were below drinking
water standards but were only slightly above levels of concern for aquatic life
(5.6 ug/1 for Cu and 47 ug/1 for Zn, U.S. EPA, 1976). Actual differences are
within the limits of analytical error. In any case, the contribution of metals to the
river by ground water seepage at the site was small and considered negligible.
Based on a review of the plant history and the available water quality and
sediment data, a monitoring program was designed. The potential pathways by
which metals could reach the river appeared to be direct discharge from the
drainage ditch, seepage of contaminated ground water, and storm water runoff.
Plant records indicated that typical flows in the drainage ditch at its confluence
with the river varied from 1 to 3 cubic feet per second (cfs) in the spring. During
extreme flood conditions, the flow in the ditch exceeded 20 cfs. In the summer,
flows in the drainage ditches at all locations were less than 0.5 cfs. Resuspension
of contaminated sediments in the ditches during storm runoff appeared to be the
most likely pathway for metals to reach the river. The specific metals of concern
were identified as As, Cd, Cu, Pb and Zn based on the processes used at the plant
and the composition of the ores which contained some arsenopyrites (As, Cu),
galena (Pb), and sphalerite (Zn, Cd).
The available soil and water quality data from the reconnaissance visit were
reviewed to determine the likely fate of the metals. Soils in the area were
cir cum neutral (pH = 6.5) and contained about 0.5 percent organic matter by weight.
Thus the metals, particularly Pb, would be expected to adsorb onto the soil
particles. In the on-site tailings piles, the pH of core samples ranged between 3.3
and 4.9. Low soil pH values had been measured in sediments in the drainage ditch
15-59
-------
just downgradient of the tailings pile. The PH of the river during the
reconnaissance was 6.9. The suspended solids concentration was 10 mg/1.
Estimates of the distribution of metals between the dissolved and adsorbed
phases for a range of partition coefficients (Kp) are shown in Table 15-3. For
example, if Kp = 104 and the suspended solids concentration was 10 mg/1, 90
percent of the metal present would be in the dissolved phase. This information
indicated that even though a metal (e.g., lead), was known to sorb strongly, a
significant amount could be transported in the dissolved phase. Thus, both water
and suspended solids should be analyzed for metals. The complete list of
parameters selected for measurement in the Phase I investigation and the rationale
*
for their selection are outlined in Table 15-4.
The sampling stations were selected to determine river quality up and
downstream of the site and to determine whether particulates with sorbed metals
were deposited on the river banks or stream bed. The sampling stations and the
rationale for their selection are listed in Table 15-5. The station locations are
shown in Figure 15-23. Because floods were considered to be one cause of
contamination incidents, samples were to be collected under both high and low flow
conditions.
Selected results of the surface water quality sampling program for spring
conditions are given below:
Dissolved Copper
Station Concentration, ug/1
35 (mouth of ditch) 1110
87 (upstream) 2.7
38 (downstream) 4.0
15-60
-------
TABLE 15-3
RELATIONSHIP OF DISSOLVED AND SORBED PHASE POLLUTANT CONCENTRATIONS
TO PARTITION COEFFICIENT AND SEDIMENT CONCENTRATION
Kp
lo"1
101
102
103
1Q4
s
(ppm)
1
10
100
1000
10000
1
10
100
1000
10000
1
10
100
1000
10000
1
10
100
1000
10000
1
10
100
1000
10000
Cw/
-------
TABLE 15-4
PARAMETERS SELECTED FOR SURFACE WATER MONITORING PROGRAM
Parameters
Metals- As, Cd,Cu,Pb,Zn
pH
Dissolved Oxygen, Sulfide.
Fe(ll), Fe(lll)
*
Alkalinity
Total Dissolved Solids
Major Cations (Ca**, Mg2 *,
N«MC*,NH*J
Major Anions (C1-, SO4,2' NO,*)
Suspended Solids
Streamflow
Rationale
Determine extent of contamination
Needed to predict sorption behavior,
metal solubility, and speciation
Needed to determine redox
conditions which influence behavior
of metals, particularly the leaching
of tailings
A measure of how well buffered a
water is; allows consideration of the
likelihood of pH change
Used as a water quality indicator and
for QA/QC checks
May identify other waste sources;
can influence fate of trace metals
Needed to predict the fraction of
metal in water which is sorbed
Needed to compute mass balances
and assist in identifying sources of
observed contamination
15-62
-------
TABLE 15-5
SELECTED SURFACE WATER MONITORING STATIONS AND RATIONALE
Station
Drainage ditch west of sit*
(Si)
Drainage ditches on sitt (S2
and S3)
Downstream of confluence of
2 ditches (S4)-
Mouth of drainage ditch (SS)
River (S6, 57, and 59)
River (58)
Media
Water and sediments
Water and sediments
•
Water and sediments
Water, suspended
sediment, bed load
Water, suspended
sediment, bed load
Water, suspended
sediment, bed load
Rational*
Deterine whether off-sit* drainage is
significant source of contamination
Identify orvsit* sources
Provide information for checking mass
balances from the 2 drainage ditches
Determine upstream water quality
Determine upstream water quality
Determine quality downstream of site
and provide data for mass balance
15-63
-------
A mass balance was computed to determine how much of the apparent decrease
from the ditch (35) to the downstream river sampling point (S8) was due to dilution
and how much could be attributed to other processes (e.g., sorption, precipitation).
The concentration in the river considering dilution alone was predicted using the
following mass balance equation:
Co a CUQU*CWQW
* Qu+Qw
where
CB * downstream concentration of pollutant in river following mixing with
ditch waters (S8), ug/1
Cw ».concentration in ditch water (S5), ug/1
Cu * concentration in river above ditch (S7), ug/1
Qw = discharge rate of ditch, ftVsec
Qu = flow rate of river above ditch, ft3/sec.
At the time of sampling, the flow in the ditch at station 35 was 1 cfs and the river
flow at station 37 was 155 cfs. Using the above equation, the predicted river
concentration for Cu ws 10 ug/1. (The observed concentration was 4 ug/1.) The
observed decrease in concentration was primarily due to dilution, although other
attenuation processes (e.g., sorption) obviously were occurring. Next, an estimate
of the expected sorbed concentration was made as follows:
X = Kp C
where
X a sorbed concentration, ug/kg
Kp * partition coefficient, I/kg
C * concentration of dissolved phase, ug/1
Here, the sorbed concentration of Cu was estimated as 8 x 105 ug/kg (800 mg/kg).
15-64
-------
Case Discussion
This case illustrates the use of site-specific data and the use of information
on the environmental fate of contaminants in the design of a surface water
monitoring program. Site data are needed to locate waste sources and .to
determine the likely flow paths by which contaminants reach rivers. * An
understanding of the general behavior of the contaminants of interest and of
factors which influence their fate is helpful in deterrtining
. >•'•; ,.•"• - • - .
be collected and what parameters, particularly;.master.
measured. Collecting data on such parameters (e.g., pH, suspended solids) ensures
that the necessary information is available to interpret the data.
15-65
-------
CASE STUDY 11: USE OP BIOASSAYS AND BIOACCUMULATION TO ASSESS
POTENTIAL BIOLOGICAL EFFECTS OF HAZARDOUS
WASTE ON AQUATIC ECOSYSTEMS
Point Illustrated
o Measurements of toxicity (I.e., bioassays) and bfoaccumulation can be
used to assess the nature and extent of potential biological impacts in
off-site areas.
Introduction
A study was conducted to determine whether leachate discharged into
surface waters had adversely affected biota in a stream adjacent to a waste site
and in a nearby lake. The components of the study included chemical analyses of
the leachate, surface waters, sediments, and tissue samples; toxicity testing of the
surface waters; and surveys of the structure and composition of the biological
communities. Tissue analyses are important for determining contaminant bio-
accumulation, and assessing potential human exposure through consumption of
aquatic organisms. Toxicity testing is important for determining contaminant
bioaccumulation, and assessing potential human exposure through consumption of
aquatic organisms. Toxicity testing is important for determining potential lethal
and sublethal effects of contaminant exposure on aquatic biota. Although
ecological analysis of community structure and composition is also an important
component of biomonitoring, it will not be discussed here since the focus is on the
relationships between the leachate source, the distributions of contaminants near
the waste site, and the toxic effects and bioaccumulation of the contaminants in
the tissues of local fauna.
Site Description
The five-acre facility is an industrial waste processing site which accepts
wastes from nearby plastic manufacturing and electroplating industries. Liquid
wastes are dewatered on site prior to removal to an off-site disposal area. The
principal wastes processed at the faclity include several organic compounds and
metals.
15-66
-------
The site contains a waste water impoundment with numerous seeps and
draining channels that transport leachate into an adjacent river (Figure 15-24).
The river flows from northeast to southwest* and is joined by a tributary stream
before entering a nearby lake. The RFA indicated an oily sheen associated with a
strong chemical odor on the surface of the stream below the treatment pond* and
further reported numerous violations of the NPDES permit. Subsequent analyses of
samples taken from the drainage channels and seeps flowing into the river showed
high concentrations of organic and trace metal contaminants, principally bis (2-
ethylhexyl) phthalate, ethylbenzene, phenol, copper, cadmium, and zinc.
Sampling Program
Six stations were sampled to assess possible toxicity and bioaccumuiation of
released substances (Figure 15-24). Station 6, located upstream from the release,
was selected as a reference location for the stream. Station 17 was selected as a
reference location for the lake since it is located away from the river mouth and
because prevailing winds from the northwest direct the river discharge along the
southeast shore of the lake away from the station. Stations 7, 15, and 18 were
selected to determine the extent of toxic impacts on river and lake biota.
Water, sediments, and tissues of bottom-dwelling fishes (brown bullhead
catfish, Ictalurus nebulosus) were collected at each station. Concentrations of
bis(2-ethylhexyl) phthalate, ethylbenzene, phenol, copper, cadmium, and zinc were
measured in each mateix. Analyses were conducted according to U.S. EPA
guidelines for sediments, water, and tissues. Water quality variables (dissolved
oxygen, temperature profiles, and alkalinity), total organic carbon in sediments,
and lipid content of tissues were also measured.
Three independent bioassays were conducted on each water sample. The test
species and endpoints used in the bioassays were those recommended in the U.S.
EPA protocol for bioassessment of hazarduos waste sites (Tetra Tech, 1983).
Growth inhibition in the alga Selanastrum capricornutum. and mortality in the
crustacean Daphnia magna were determined using U.S. EPA (1985) short-term
methods for chronic toxicity testing. Inhibition of enzyme-mediated luminescence
15-67
-------
§
o
JE
"A
E
IA
15-68
-------
in the bacterium Photobacterium phosphoreum (i.e., the Microtox procedure) was
measured according to the methods establish by Bulich et al. (1981).
Results
Results of the survey indicated that concentrations of organic contaminants
in the surface waters were generally less than U.S. EPA water quality criteria* but
that concentrations of inorganic contamiaaots-generally exceeded water quality
.criteria at Stations 7, 15, and 18 (Table 15-6). In comparison with the reference
stations, significant sediment contamination was evident at Stations 7, 15, and 18
for the three trace metals (Table 15-7). Tissue concentrations of organic
substances'exceeded detection limits for bis(2-ethylhexyl) phthalate at Stations 7
and 15, and for ethylbenzene at Station 7 (Table 15-8). However, trace metal
concentrations in tissues were highly elevated at Stations 7, and 15, but only
slightly elevated at Station 18.
The bioassay data showed a considerable range in sensitivity, with the algal
bioassay being the most sensitive (Table 15-9). Consequently, the bioassay results
were normalized to the least toxic of the reference stations (i.e., Station 6) in
order to compensate for the wide range of sensitivity among the test species
(Table 15-10). Overall, the bioassay results showed a high degree of agreement
with contaminant concentrations in water and sediments (Figure 15-25, Table 15-6
and 15-7). Stations 7 and 15 were highly toxic, and Station 18 was moderately
toxic. Only the algal bioassay indicated significant, but low, toxicity at Station 17
(the lake reference station).
In summary, the results indicated that the organic contaminants were less of
a problem than the trace metals in terms of bioaccumulation and potential
toxicity. Most of the observed toxicity was attributed to trace metal
contamination which is consistent with the elevated concentrations of trace metals
measured in the water, sediments, and tissues.
15-69
-------
TABLE 15-6
MEAN CONCENTRATIONS (wfl/t) OF ORGANIC SUBSTANCES AND TRACE METALS
IN LEACHATE AND SURFACE WATERS*
Chemical Class
Base Neutral
Volatile
Acid Extractable
Mttals
Chemical
8is(2-ethylhexyO
phthaiatt
Ethyl benzene
Phtnol
Copper
Zinc
Cadmium
Station
S««p
LI
600
100
1500
4300
35000
4800
River
6
2
1
<1
<1
17
<1
*
River
7
11
1
18.37
489
4290
146
lakt
15
10
<1
<1
56
1100
49
Lakt
18
1
1
<1
26
37
<1
Lakt
17
2
2
<1
2
35
<1
Water Quality
Criteria*
Acutt
940
32000
10200
18
320
3.9
Chronic
3
NAC
2560
12
47
1.1
•Wvtr and lakt alkalinity « 100mgCaC03/L
Tract mttal criteria adjusted for alkalinity
'Not avaiiablt for this substance
15-70
-------
TABLE 15-7
MEAN SEDIMENT CONCENTRATIONS (wg/kg DRY WT) OF ORGANIC
SUBSTANCES AND TRACE METALS
Chemical Class
Base Neutral
•
Volatile
Acid Extractable
Metals
Chemical
Bis(2-ethylhcxyl)
phthalate
Ethyl benzene
Phenol
Copper
Zinc
Cadmium
Station
Seep
LI
NA*
NA
NA
NA
NA
NA
River
6
216
10
<30
3
11
<0.1
River
7
1188
34
<30
1663
28314
19
Lake
15
1080
20
<30
190
7260
6
Lake
18
108
14
<30
88
24
<0.1
Lake
17
216
8
<30
7
23
<0.1
'Not applicable (NA).
15-71
-------
TABLE 15-8
MEAN UVER TISSUE CONCENTRATIONS (pa/kg WET WT) OF ORGANIC
SUBSTANCES AND TRACE METALS
Chemical Class
Base Ntutral •
Volatilt
Acid Extractable
Metals
Chemical
8is(2-ethylhexyl)
phthalate
Ethyl benzene
Phenol
Copper
Zinc
Cadmium
Station
Seep
11
NA*
NA
NA
NA
NA
NA
. River
6
<25
<5
<30
118
983
115
River
7
95
9
<30
1600
28400
1600
Lake
15
86
<5
<30
750
8500
639
Lake
18
<25
<5
<30
237
2139
190
Lake
17
<25
<5
<30
180
1420
125
'Not applicable (NA).
15-72
-------
TABLE 15-9
MEAN LC50 AND EC50 VALUES (PERCENT DILUTION) FOR SURFACE-WATER
BIOASSAYS*
Bioassay
Algae
Daphnia
Microtox
Endpoint
growth inhibition
(EC50H)*
Mortality (LC50H)*
D«creas«d
luminescence
(EC50%)'
Station
Seep
L1
NAB
NA
NA
River
6
>100<
>100
>100
River
7
0.4
3.3
5.6
Lake
15
10.0
18.5
15.0
Lake
18
24.9
100.0
43.4
Lake
17
75.0
90.0
>100
'Percent dilution required corresponding to a 50 percent response
"Not applicable (NA) because leachate toxicity was not tested
'Response of > 100 indicates that samples were not toxic at all dilutions tested
'Percent dilution corresponding to 50 percent mortality
15-73
-------
TABLE 15-10
RELATIVE TOXIGTY OF SURFACE-WATER SAMPLES*
Bioassay
Algae
Oaphnia
Microtox
Endpoint
Growth inhibition
(EC50%)
Mortality (LC50%)
Decreased
luminescence
(EC50%)4
Station
Seep
LI
NA"
NA
NA
River
6
0.0
0.0
0.0
River
7
99.6
96.7
94.4
Lake
15
90.0
81.5
85.0
tak*
18
75.1
0.0
56.6
Uk«
17
25.0
10.0
0.0
'Rotative toxicity * 100 x [(R«ftr«nce Station - Impacted Station)/R«f«r«nc« Station]
"Not applicable (NA) because leachate toxicity was not tested
15-74
-------
90-
80 -
9 70 -
1 *° "
^*
R 80 -
0 40-
S
a 30-
20 -
10 -
•
1
1
^
^
1
v>
v
raw e
Late 15
Station
Dophnlo
18
Mteretox
17
Figure 15-25. Bioassay Responses to Surface Water Samples
15-75
-------
Case Discussion
This ease study provides an example of a biomonitorinf program designed to
characterize the relationship between a contaminant source, contaminant
concentrations in sediments and water, bioaccumulation in tissues, and receiving-
water toxicity. It should be recognized that in most instances, the relationship
between contaminant concentrations in the water and toxicity will not be as clear-
cut as described in this example. Consideration of the chemical composition in
leachate samples, mass balance calculations, and transport and fate mechanisms
may indicate that sediments are the primary repository of contaminants. In such
instances, sediment bioassays rather than receiving-water bioassays may be better
suited for characterization of potential toxic effects on local fauna.
References
Bulich, A.A., M.W. Greene, and D.L. tsenberg. 1981. Reliabiltv of the bacterial
luminescence assay for determination of the toxicity of pure compounds and
complex effluent, pp. 338-347. In: Aquatic toxicology and hazard assessment:
Proceedings of the fourth annual symposium. ASTM STP 737. D.R. Branson and
K.L. Dickson (eds). American Society for Testing and Materials, Philadelphia, PA.
Tetra Tech. 1983. Protocol for bioassessment of hazardous waste sites. EPA-
600/2-83-054. Lafayette, CA. 42 pp. + appendices.
U.S. Environmental Protection Agency. 198S. Short-term methods for estimating
the chronic toxicity of effluents and receiving waters to freshwater organisms.
EPA/600/4- * V014. U.S. EPA, Environmental Monitoring and Support Laboratory,
Cincinnati, CH. 162 pp.
15-76
-------
CASE STUDY 12: SAMPLING OF SEDIMENTS ASSOCIATED WITH SURFACE
RUNOFF
Point Illustrated
o Contaminated sediments associated with surface runoff pathways
(rivlets or channels) are indicative of the migration of chemicals via
overland flow.
Introduction
This facility is a secondary lead smelting plant which began operation in
1976. The. plant reclaims lead from materials such as waste automotive batteries,
byproducts of lead weight manufacture, and wastewater sludges. Lead grid plates
from salvaged batteries are temporarily stored on site in an open pile prior to being
re-melted. It is therefore appropriate to conduct some form of runoff sampling to
monitor migration of contaminants from the site via this route.
Facility Description
The facility covers approximately 2,000 ft2 and is situated in an area
primarily used for farming. A creek flows adjacent to the plant and drains into a
major river 6 miles west of the site. Population is sparse with the nearest town 4
miles to the south. In the past, there have been four on-site impoundments in
operation and two landfills. In addition, blast furnace slag, lead grid plates, and
rubber chips from the recycled batteries have been stored in two on-site waste
piles.
Sediment Sampling
Four sediment samples (020, 022, 025, and 027) were collected from surface
runoff pathways and a creek which receives runoff from the site. Figure 15-26
shows the locations of the runoff pathways in relation to the facility and the four
sampling points. Additional sediment samples were collected from the creek at
various points upstream and downstream of known overland leachate seeps and
surface water runoff routes. The program design enabled comparison between
concentrations at different sections of the creek and background locations in
relation to the runoff pathways.
15-77
-------
CLOSED
IMPOUNDMENTS 1
CLOSED RUBBER CHIP
STORAGE_AREA
OW12
N
CLOSED SLAG
STORAGE AREA
CLOSED
IMPOUNDMENT 4
LEGEND
• DRILL HOLES
® WASTE
A WELLS
SCALE
0 200
Feet
OW10
ILL,
Figure 15-26. Surface Water and Sediment Sample Locations
15-78
-------
Results
Table 15-11 presents the concentrations of lead and arsenic measured on the
four surface runoff pathways and at location 029, which represents an upstream
background concentration (Figure 15-26). It is clear that highly elevated levels of
lead were detected in all four of the runoff pathway samples. The highest
concentration of lead, 1,900 ppm, was detected in the western most portion of the
site. Runoff pathway sediment at the northern end of the facility, adjacent to the
slag storage area, recorded 1,600 ppm of lead. Concentrations of this order
represent a substantial source of sediment contamination.
Table 15-11
ARSENIC AND LEAD CONCENTRATIONS (PPM) IN RUNOFF
SEDIMENT SAMPLES
Sampling Location
Contaminant
Arsenic
Lead
I 020
11.0
1300
# 022
9.6
1900
I 025
2.0
1600
» 027
8.9
1700
Background
* 029
< .1
11.0
Case Discussion
This case illustrates the importance of monitoring surface runoff pathways,
since they can represent a major route of contaminant migration from a site,
particularly for contaminants which are likely to be sorbed on or exist as fine
panicles. This type of monitoring is especially useful for units capable of
generating overland flows. Such monitoring can establish the need for corrective
measures (e.g., surface runon/runoff controls and/or some form of waste leachate
collection system).
15-79
-------
CASE STUDY 13: SAMPLING PROGRAM DESIGN FOR CHARACTERIZATION
OP A WASATEWATER HOLDING IMPOUNDMENT
Points Illustrated
o Sampling programs must consider three-dimensional variation in
contaminant distribution in an impoundment.
o Sampling programs must encompass active areas near inflows and
outflows, and potentially stagnant areas in the corner of an
impoundment.
Introduction
This study was conducted to assess whether an active liquid waste
impoundment could be assumed to be of homogenous composition for the purpose of
determining air emissions. This case shows the design of an appropriate sampling
grid to establish the three-dimensional composition of the impoundment.
Facility Description
The unit being investigated in this study is a wastewater impoundment at a
chemical manufacturing plant. The plant primarily produces nitrated aromatics
and aromatic amines. Raw materials include benzene, toluene, nitric acid, and
sulphuric acid. Wastewater from the chemical processing is discharged into the
impoundment prior to being treated for release into a nearby water body. The
impoundment has an approximate surface area of 3,750 m2 and a depth of 3 m.
Sampling Program
For the most part, sampling involved the collection of grab samples using an
extended reach man-lift-vehicle. The program was designed to collect samples at
different locations and depths in the impoundment.
15-80
-------
Sampling Locations and Procedures—
Sampling Grid - The wastewater impoundment was divided into 15 segments
of equal area. Within this grid, eight sampling locations were selected which
included all pertinent areas of the impoundment, such as active portions near the
inflows and outflows, potential stagnant areas in the corners, and offshore points
near the center line of the impoundment.
It was decided to take samples from four depths in the liquid layer and one
from the bottom sediments at each of the eight locations. Figure 15-27 shows the
impoundment schematic and sampling locations.
Liquid Sampling - A total of 32 liquid grab samples were taken. These were
analyzed for the following parameters: for all identifiable volatile organic
compounds (VOCs) and semivolatile organic compounds (SVOCs) using gas
chromatograph/mass spectroscopy; and selected VOCs and SVOCs by gas
chromatography using a flame ionization detector.
Sediment/Sludge Sampling - The bottom layer was sampled using a Ponar grab
sampler. The same analyses were performed on the eight sediment/sludge samples
as on the liquid samples.
Meteorological Monitoring - The ambient meteorological conditions were
monitored throughout the sampling period, including wind speed, wind direction,
and air temperature. A video camera was also used to record the movement of
surface scum on the impoundment.
Table 15-12 summarizes the sampling locations and analyses, including
locations where QC data were collected.
Results
From the sampling program, it was discovered that approximately 99 percent
of the organic compounds (by weight) were contained in the bottom sludge layer.
15-81
-------
345'
\
•
/
aa
G H
)
F
©
it
0D £ ®
(I.
C
©
A B
1
| []
ABACffn 0 A LJBl lfcJ/» i ^^^A^lAk
/
— _
\
J*
o
0
Of
0
w
a
EXISTING
N
PLANT SUMP EFFLUENT
INFLUENT/LAGOON
EFFLUENT
BOILER BACK WASH EFFLUENT
PRIMARY PLANT EFFLUENT
Figure 15-27. Schematic of Waatewater Holding Impoundment Showing Sampling
Locations
15-82
-------
TABLE 15-12
SUMMARY OF SAMPLING AND ANALYSIS PROGRAM FOR
WASTE WATER IMPOUNDMENT
Location
A-1
A-2
A-3
A-4
A-S
8-1
B-2
B-3
8-4
8-5
C-1
C-2
C-3
C-4
D-1
D-2
0-3
D-4
D-5
0«pth
(Feet)
0-1
2
4
6
Bottom
Sediment
0-1
2
4
6
Bottom
Sediment
0-1
2
4
Bottom
Sediment
0-1
2
4
6
Bottom
Sediment
Sample Analyses
GC/FID
VOA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
GC/MS
VOA
X
X
X
X
X
X
X
X
TOC
X
X
X
X
X
X
X
X
POC
X
X
X
X
Onsite
Parameters'
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
GC/FID
svoc
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
GC/MS
SVOC
X
X
X
X
X
X
X
X
a Includes pH, turbidity, specific conductance, and dissolved oxygen measurements.
X Indicates locations where QC samples were collected.
15-83
-------
TABLE 15-12
SUMMARY OF SAMPLING AND ANALYSIS PROGRAM FOR
WASTE WATER IMPOUNDMENT
PAGE TWO
Location
E-1
E-2
E-3
E-4
E-5
F-1
F-2
F-3
F-4
F-S
G-1
G-2
G-3
G-4
G-5
H-1
H-2
H-3
H-4
H-5
Depth
(Feet)
0-1
2
4
6
Bottom
Sediment
0-1
2
4
6
Bottom
Sediment
0-1
2
4
6
Bottom
Sediment
0-1
2
4
6
Bottom
Sediment
GC/FIO
VGA
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
•
X
X
X
X
X
Sample Analyses
GC/MS
VOA
X
X
X
X
X
X
X
X
TOC
X
X
X
X
X
X
X
X
POC
X
X
X
X
Onsite
Parameters*
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
GC/FID
svoc
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
GC/MS
svoc
X
X
X
X
X
X
X
X .
a Includes pH, turbidity, specific conductance, and dissolved oxygen measurements.
X Indicates locations where QC samples were collected.
15-84
-------
Vertical and horizontal variation in the composition of the lagoon was apparent.
The degree of horizontal variation was relatively small, but sample point "A"
showed consideraby higher concentrations of 2,4-dinitrophenol than the other
locations. This could have resulted from a recent discharge from the outflow at
the southern end of the impoundment. Vertical variation in composition showed a
general trend of increasing concentration with depth, but certain chemicals tended
to have higher concentrations at mid-depth in the impoundment.
Case Discussion
This case provides an example of a sampling program at an area! source
designed to yield accurate information for characterizing air emissions from the
unit. The study illustrated the importance of characterizing the organic
composition of the lagoon in three dimensions and considering variations resulting
from inflow and outflow areas.
It should be mentioned that this study did not consider variation in the
chemical composition of the impoundment with time. To obtain this information,
it would be necessary to conduct subsequent sampling programs at different times.
From this study, it is apparent that chemical composition varies both horizontally
and vertically, and is likely to change depending on inflows and outflows of wastes.
This sampling program is therefore limited to effectively characterizing
composition at a single point in time.
15-85
-------
CASE STUDY 14: USE OP AIR MONITORING DATA AND DISPERSION
MODELING TO DETERMINE CONTAMINANT
CONCENTRATIONS DOWN-WIND OP A LAND DISPOSAL
PACILITY
Point Illustrated
o How to use air dispersion modeling and air monitoring data to estimate
contaminant concentrations.
Introduction
Concern over possible vinyl chloride transport into the residential areas
adjacent to a land disposal facility prompted initiation of this study. A preliminary
survey involving a minimal sampling effort along with the application of an air
dispersion model was used to assess potential health hazards prior to conducting a
more thorough monitoring program.
Facility Description
The facility is a landfill which has been in operation since 1963. The facility
occupies an area of 583 acres* of which 228 acres contain hazardous and municipal
waste. The facility and surrounding terrain is hilly with elevations ranging from
600 to 1150 feet above mean sea level. Residential areas are located immediately
adjacent to the south and southeast facility boundaries* as shown in Figure 15-28.
The facility previously received waste solutions from the synthesis of
polyvinyl chloride which included the vinyl chloride monomer. Gas generated by
municipal waste decomposition and chemical waste volatilization are collected at
the site with an elaborate piping system and are burned in a smokeless flare. The
primary combustible in the gas is methane, with traces of vinyl chloride present
along with other compounds.
Program Design/Data Collection
A preliminary survey using a combination of air monitoring and mathematical
modeling was used to assess potential vinyl chloride pollution of the residential
areas downwind of the facility. An analysis of meteorological data obtained from a
15-86
-------
15-87
-------
nearby airport indicated that wind patterns in the area were characterized by a
regular daily reversal of wind direction from a daytime westerly sea breeze to a
nighttime downslope drainage wind from the north or east beginning after midnight
in summer and after sunset in winter. In order to minimize the sampling effort,
only two air monitoring stations were selected. The station locations were based on
the locations of the nearby receptor areas in conjunction with the prevailing wind
conditions and the locations in the landfill where polyvinyl chloride emissions were
occurring (Figure 15-28). Station A was located on the upwind side of the
residential area 180 meters from the southeast boundary of the facility. This
»
location was selected to measure the plumes from emission area B2 during the
daytime westerly winds and from emission area Al during the nocturnal downslope
drainage from the north. Station B was located on the upwind edge of the
residential area 25 meters from the southern boundary of the facility. This
location was selected to measure the plumes from emission area Bl during
nocturnal downslope drainage from the north and from emission area A2 during
nocturnal valley drainage from the east. Ambient polyvinyl chloride
concentrations upwind of the facility were assumed negligible, so upwind
monitoring was not necessary.
Air samples were collected over a 24-hour period on two days in July and on
three days in August. The July sampling period was selected to represent typical
conditions of light to moderate wind (10 to 15 mph). The August sampling period
was conducted to represent worst-case conditions under steady calm winds (less
than 8 mph) combined with high air and ground temperatures which tend to
maximize emission rates. The samples were collected using Tedlar bags and were
analyzed by gas chromatography/flame ionization detection (GC/FID).
Vinyl chloride emission rates from the landfill were estimated using a gas
emission equation (Shen, 1981). The estimated emission rates were functions of the
area of the landfill where vinyl chloride emissions were known to occur, soil
characteristics, chemical characteristics, and temperature. The emission areas
affecting a downwind monitoring station were assumed to vary with different wind
directions due to the effects of topographic features. For example, emission area
A2 used for nocturnal valley drainage from the east is only a fraction of emission
area B2 assumed for the daytime westerly winds, even though both areas represent
the same source. These areas were calculated by drawing sectors from each
15-88
-------
monitoring station along the extremes of wind direction for each wind pattern
using ridgelines and the landfill boundary to determine the area limits. Al and Bl
on Figure 15-28 show the exposed areas estimated for valley drainage and sea
breeze conditions, respectively.
The estimated emission rates were used in conjunction with an air dispersion
model (U.S. EPA, 1981) to predict the concentrations of vinyl chloride at
monitoring station A and B. The major input parameters included the gas emission
rates discussed above, the source areas, and wind speed. The meteorological and
landfill data used in the model predictions corresponded to the air monitoring
periods during July and August. The model results were averaged for each of the
24-hour monitoring periods to facilitate comparison with the.monitoring data.
Results
Table 15-13 compares the predicted and measured 24-hour average vinyl
chloride concentrations at stations A and B for each of the five sampling days. The
model results are accurate to within a factor of two for all sampling periods at
both stations. The use of on-site meteorological data would probably have
improved the accuracy of the predictions since off-site data from the nearby
airport may not have reflected localized conditions (e.g., topographic effects)
which could effect the wind speed, direction, and air temperature used in the
calculations.
Another area where error may have been introduced was in the calculation of
emission rates. Several factors could have reduced the accuracy of these
estimates including difficulty in calculating the effective emission areas due to the
irregular topography, as well as spatial variations in parameters such as soil
porosity and depth of landfill cover which were assumed constant in the analysis.
15-89
-------
TABLE 15-13
COMPARISON OF MEASURED AND PREDICTED
VINYL CHLORIDE CONCENTRATIONS (PPB)
(FROM BAKER AND MACKAY, 1985)
Sitt
A
B
Date
Measured
ModtH
Model 2
Modtl3
Model 4
Measured
Model 1
Model 2
Model 3
Model 4
March 7-8
12
25.1
9.1
4.9
45.9
5
24.3
11.5
5.5
35.5
March 8-9
5
19.4
7.3
4.0
42.8
7
13.1
6.1
3.7
28.6
August 5-6
7
40.0
14.8
8.0
76.7
2
30.4
14.2
8.4
62.8
August 6-7
12
45.7
16.7
9.0
81.1
4
32.4
15.3
8.7
62.0
August 7-8
9
45.5
16.9
9.1
87.3
<2
32.2
15.2
8.9
66.7
5-Day
Average
9
35.1
13.0
7.0
66.8
4
26.5
12.5
7.0
51.1
•Key
Model 1
Model 2
Model 3
Model 4
ground level point source (Shen, 1982)
virtual point source (Turner, 1969)
virtual point source (U.S. EPA, 1981)
simple box (Giffofd and Hanna, 1970)
15-90
-------
Case Discussion
Air dispersion models can be useful for estimating concentrations downwind
of waste disposal areas. Although many models are available, the ISC (Industrial
Source Complex) model (EPA, 1977, 1986) is recommended for most applications.
However, other EPA-approved models (e.g., UNAMAP series) can also be used
where appropriate. For this preliminary survey, a simpler screening model was
used.
Air monitoring should always be performed in conjunction with dispersion
modeling to verify the accuracy of model predictions. After the model has been
verified, it*can be used to estimate downwind concentrations under a wide range of
meteorological conditions, under different (e.g., future) waste management
scenarios, and at different potential receptor areas (e.g., future residential
developments). It can also be used to estimate pollutant concentrations in areas
where direct monitoring would be difficult due to limitations in analytical
techniques (i.e., concentrations below detection limits), for example, areas where
low concentrations of a highly toxic compound are present. Dispersion models are
also useful for analyzing multiple sources whose plumes overlap since the
incremental contamination associated with each source can be separated. In
addition, they are useful for selecting station locations in air monitoring programs
since they can estimate the trajectory and extent of the contaminant plume prior
to making any measurements.
References
Baker, L.W. and K.P. MacKay. 1985. Screening Models for Estimating Toxic Air
Pollution Near a Hazardous Waste Landfill. Journal of Air Pollution Control
Association, 35:11.
Shen, T. 1981. Control Techniques for Gas Emissions from Hazardous Waste
Landfills. Journal of Air Pollution Control Association, 31:132.
U.S. EPA. 1977. Guidelines for Air Quality Maintenance Planning and Analysis.
Vol. 10 (Revised). Procedures for Evaluating Air Quality Impact of New Stationary
Sources. EPA-450/4-77-001. Washington, D.C.
15-91
-------
G"i'""""°"Alr9,,.MtYMov,,>,). EPA-450/Z-78-027R.
15-92
-------
CASE STUDY 15: USE OF METEOROLOGICAL DATA TO DESIGN AN AIR
MONITORING NETWORK
Points Illustrated
o How to design an air monitoring program
o How to conduct an upwind/downwind monitoring program when multiple
sources are involved.
Introduction
An *air monitoring program was conducted to characterize hazardous
constituents that were being released from a wood treatment facility.
Meteorological data were first collected to determine the wind patterns in the
area. The wind direction data together with the locations of the potential emission
sources were then used to select air sampling locations.
Facility Description
The site is a 12-acre wood treatment facility located in an inland,
topographically flat area of the southeast. Creosote and pentachlorophenol are
used as wood preservatives, and heavy metal salts have been used in the past.
Creosote and pentachlorophenol are currently disposed in an aerated surface
impoundment. Past waste disposal practices included treatment and disposal of the
metal salts in a surface impoundment, and disposal of contaminated wood shavings
in waste piles. The constituents of concern in the facility's waste stream include
phenols, cresola, and poly cyclic aromatic hydrocarbons (PAH) in the creosote;
dibenzodiozins and dibenzofurans as contaminants in pentchlorophenol; and
paniculate heave metals. The potential emission sources (Figure 15-29) include
the container storage facility for creosote and pentachlorophenol, the wood
treatment and product storage areas, the aerated surface impoundment for the
creosote and pentachlorophenol wastes, and the contaminated soil area which
previously contained both the surface impoundment for treating the metal salts and
the wood shavings storage area. Seepage from these waste management units has
resulted in documented ground water and surface water contamination.
15-93
-------
AVAILING
IND
RECTON
INACTIVE SURFACE
IMPOUNDMENT AND
CONTAMINATED
WOOD SHAVINGS
STORAGE AREA
AERATED
SURFACE
IMPOUNDMENT
i STATION 2 (V)
OFFICE
STATION 4 (V!
TREATMENT
AND PRODUCT
STORAGE AREAS
I
^
(STATION 1 (PV.M)
CONTAINER
STORAGE
FACILITY
H h-
GATE
STATION 3 (PV)
KEY
• AIR MONITORING STATIONS
P PARTICULATE MONTORINC
V VOLATILE CONSTITUENT MONfTC
M METEOROLOGICAL MONITORING
Figure 15-29. Site Plan and Locations of Air Monitoring Stations
15-94
-------
The area surrounding the facility has experienced substantial development
over the yean. A shopping center is now adjacent to the eastern site perimeter.
This development has significantly increased the number of potential receptors for
air releases of hazardous constituents.
Program Design/Data Collection
Preliminary Screening Survey—
A limited-on-site air screening survey was first conducted to document air
releases of potentially hazardous consituents and to verify the need to conduct an
air monitoring program. Total hydrocarbon (THC) levels were measured with a
portable THC analyzer downwind of the aerated surface impoundment, wood
treatment area, and product storage area. Measurements were also made upwind
of all units to provide background concentrations. Because THC levels detected
downwind were significantly higher than background levels* a comprehensive air
monitoring program was designed and implemented.
Waste Characterization—
To develop an adequate air monitoring program, the composition of wastes
handled in each waste management unit was first determined to identify which
constituents were likely to be present in the air releases. Existing water quality
data indicated contamination of ground water with cresois, phenol, and PAHs and
of surface water with phenols, benzene, chlorobenzene, and ethylbenzene. A field
sampling program was developed to characterize further the facility's waste
stream. Waste water samples were collected from the aerated surface
impoundment and soil samples were collected from the heavy metal salt waste
treatment/disposal area. Analytical data from this sampling effort confirmed the
presence of the constituents previously identified. Additional constituents
detected included toluene and xylenes in surface impoundment wastes, and arsenic,
copper, chromium, and zinc in the treatment/disposal area.
15-95
-------
Based on their individual emission potentials and potentials for health and
environmental hazards, the following constituents were selected for measurement
in the air monitoring program:
Volatile/semi-volatile constituents: toluene, benzene, total phenols, penta-
chlorophenol, PAHs, cresols
Particulate constituents: aresenic, copper, chromium, zinc.
Meteorological Data Collection-
Meteorological information is critical for designing an air monitoring
program since stations must be located both upwind and downwind of the
contaminant sources. Therefore, a one-month meteorological monitoring survey
was conducted. The survey was conducted under conditions considered *•> be
representative of the summer months during which air samples would be collected.
Summer represented worst-case conditions of light steady winds and warm
temperatures. The collected meteorological data showed that the local wind
direction was from the southeast. No well-defined secondary wind flows were
identified. Minor changes were observed in prevailing wind direction over a 24-
hour period due to reduction of wind speed at night.
Initial Monitoring—
•
The meteorological data were used with the EPA atmospheric dispersion
model, ISC (Industrial Source Complex Model), to estimate worst-case air emission
concentrations and to help determine the locations for the air sampling stations.
The ISC model was used because it is capable of simulating conditions of point and
non-point source air emissions. Using the established southeast wind direction,
maximum downwind concentrations were predicted for different meteorological
conditions (e.g., wind speed). Upwind background stations and downwind
monitoring stations were selected based on the predicted dispersion pathways.
Since the plumes from the individual waste management areas overlapped, the
model also provided a means for separating the incremental contamination due to
each source.
15-96
-------
Figure 15-29 shows the locations of the selected sampling stations. Station 1
is the upwind background station. Here background volatile concentrations,
paniculate concentrations, and meteorological conditions were monitored.
Stations 2 and 4 were located to identify volatile emissions from the aerated
surface impoundment and wood treatment/product storage areas, respectively.
Station 3 was located downwind of the inactive surface impoundment/wood
shavings disposal area. The location of this station was sited to document releases
from these waste management units and to document worst case concentrations of
volatiles and particulates at the site perimeter. A trailer-mounted air monitoring
station was used to supplement the permanent stations and to account for any
variability in wind direction.
Sample Collection—
The air quality monitoring was conducted over a three-month period during
the summer. Meteorological variables were measured continuously on site
throughout the study. Air samples were taken over a 24-hour period approximately
every six days. The sampling dates were flexible to insure that worst-case
conditions were documented.
Volatile and semi-volatile constituents were sampled by drawing ambient air
through a sampling cartridge containing sorbent media. A modified high volume
sampler consisting of a glass fiber filter with a polyurethane foam backup sorbent
(EPA Method TO4) was used to sample for total phenols, pentachlorophenol, and
PAHs. Benzene and toluene were collected on Tenax sampling cartridges (EPA
Method TO1) and cresol was collected on silica gel cartridges (KIOSH Method
Z001). Particulates were collected on filter cassettes using high-volume samplers.
In addition to the analytical parameters previously discussed, Appendix VIII
constituents and RCRA metals were analyzed on the first few sets of samples.
These analyses were conducted to identify air releases of constituents other than
those known to be present. The results indicated that no additional constituents
were present in significant concentrations, so the additional analyses were dropped
for the remainder of the study.
15-97
-------
Program Results/Data Analysis
Standard sampling/analytical methods were available for all of the target
monitoring constituents. Analytical detection limits were below specific health
and environmental criteria for all constituents except cresol. The high analytical
detection limit for cresol which exceeded reference health criteria complicated
data analysis. This difficulty was handled by the routine collection and analysis of
waste water samples during the air monitoring program. These data were used to
estimate cresol levels in the air by comparing its emission potential index to the
other air monitoring constituents which have relatively low detection levels.
Analytical results obtained during this sampling program established that
fugitive air emissions exceeded reference health criteria. Source control measures
were implemented to reduce emission concentrations below health criteria levels.
Subsequent air monitoring was conducted at the same stations used previously on a
weekly basis immediately after implementation of the remedial measures, and on a
quarterly basis thereafter.
Case Discussion
This case illustrates the sequence of tasks needed to design an air monitoring
program at a site with multiple air emission sources. An initial problem at this site
was the lack of evidence that air emissions posed a threat to public health or the
environment. An initial field survey was conducted to identify local prevailing
wind patterns and to identify potential downwind receptors of fugitive air
emissions.
The meteorological survey results were used to design an effective
monitoring network. Monitoring station locations were selected to obtain
background conditions and to document air releases downwind of each emission
source. Also, the monitoring strategy included use of a portable sampling station
to provide flexibility in sampling locations to account for variation in wind
direction. Spatial variability in air concentration levels was assesed with the aid of
an air dispersion model to assist in data interpretation.
15-98
-------
Air emissions data documented an air release of hazardous constituents above
health crtiteria levels. Remedial measures were implemented, and periodic
subsequent monitoring was conducted to insure compliance with health criteria.
References
Methods T01 and T04, Compendium of Methods for Determination of Toxic Organic
Compounds in Ambient Air. 1984, EPA-600/4-84-041.
Method Z001, NISOH Manual of Analytical Methods. 1984, National Institute of
Occupational Safety and Health.
15-99
-------
CASE STUDY 16: USE OF THE 40 CFR 261 LISTING BACKGROUND
DOCUMENTS FOR SELECTING MONITORING
CONSTITUENTS
Point Illustrated
o The 40 CFR 261 Listing Background Documents can be of direct help in
selecting monitoring constituents.
Introduction
The RCRA Hazardous Waste Listing Background Documents developed for
the identification and listing of hazardous wastes under 40 CFR Part 261 represent
one source of potential information on waste-specific constituents and their
physical and chemical characteristics. The documents contain information on the
generation, composition, and management of listed waste streams from generic and
industry-specific sources. In addition to identifying hazardous constituents that
are present in the wastes, the documents may also provide data on potential
decomposition products. In some background documents, migratory potentials are
discussed and exposure pathways are identified.
Appendix B of the Listing Document provides more detailed information on
the fate and transport of hazardous constituents. Major physical and chemical
properties of selected constituents are listed, including molecular weights, vapor
pressures and solubilities, octanol-water partition coefficients, hydrolysis rates,
biodegradation rates, and volatilization rates. Another section of the appendix
estimates the migratory potential and environmental persistence of selected
constituents based on a conceptual model of disposal in an unconfined landfill or
lagoon.
The appropriate uses and limitations of the Listing Documents are outlined in
Table 15-14. A case study on how the Documents may be used in investigating a
release follows.
15-100
-------
TABLE 15-14
USES AND LIMITATIONS OF THE USTING BACKGROUND DOCUMENTS
Us«s
Limitations
• Identifies the hazardous constituents for
which a waste was listed
e Applicable only for listed hazardous wastes
e In some cases, provides information on
additional hazardous constituents which
may be present in a listed waste
Industry coverage may be limited in scope, e.g.,
the wood preserving industry. Listing
Documents only cover organic preservatives, not
inorganics (-15 percent of the industry), such as
inorganic arsenic salts
e in some cases, identifies decomposition
products of hazardous constituents
e Data may not be comprehensive, i.e., not all
potentially hazardous constituents may be
identified. Generally, limited to the most toxic
constituents comon to the industry as a whole
e Provides overview of industry; gives
perspective on range of waste generated
(both quantity and general
characteristics)
Data may not be specific. Constituents and
waste characteristic data often represent an
industry average which encompases many
different types of production processes and
waste treatment operations
e May provide waste-specific characteristics
data such as density, pH, and teachability
Listing Documents were developed from
data/reports available to EPA at the time,
resulting in varying levels of detail for different
documents
e May provide useful information on the
migratory potential, mobility, and
environmental persistence oicertain
hazardous consistuents
Hazardous waste listings are periodically
updated and revised, yet this may not be
reflected in the Background Documents
e May list physical and chemical properties
of selected constituents
Listing Documents for certain industries, e.g.,
the pesticides industry, may be subject to CBI
censorship due to the presence of confidential
business information. In such cases, constituent
data may be unavailable (i.e., expurgated from
the document)
15-101
-------
Facility Description
The facility is a wood preserving plant located in the southeast. The facility
uses a steaming process to treat southern pine and timber. Contaminated vapors
from the wood treating process are condensed and transported to an oil/water
separator to reclaim free oils and preserving chemicals. The bottom sediment
sludge from this and subsequent waste water treatment units is a RCRA listed
hazardous waste: K001.
Use of Listing Background Documents
Due to the presence of small, but detectable, levels of phenolic compounds in
the ground water of an adjacent property, a RCRA Facility Assessment (RFA) was
conducted and it was determined that a release from the facility had occurred.
The owner was instructed to conduct a RCRA Facility Investigation (RFI). Before
embarking on an extensive waste sampling and analysis program, the owner decided
to explore existing sources of information in order to better focus analytical
efforts.
The owner obtained a copy of the Wood Preserving Industry Listing
Background Document from the RCRA Docket at EPA Headquarters. He also had
available a copy of 40 CFR Part 261, Appendix VII, which identifies the hazardous
constituents for which his waste was listed. For K001, he found the following
»
hazardous constituents listed: pentachlorophenol, phenol, 2-chlorophenol, p-chloro-
ra-cresol, 2,4-dimethylphenyl, 2,4-dinitrophenol, triohlorophenols, tetrachloro-
phenols, 2,4-dichlorophenol, creosote, chrysene, naphthalene, fluoranthene,
benz(b)fluoranthene, benz(a)pyrene, ideno
-------
Examining the facility records, he determined that pentachlorophenol had been the
sole preservative used; moreover, it had come from a single manufacturer. Based
on a demonstrable absence of creosote use, the owner felt confident in excluding
creosote and PAHs.
To help focus on which phenolics might be present in his waste, the owner
turned to the Composition section of the Listing Document. In Table 4, he found
typical compositions of commercial grade pentachlorophenol. The sample from his
manufacturer contained 84.6 percent pentachlorophenol, 3 percent
tetrachlorophenol, and ppm levels of poly chlorinated dlbenzo-p-dioxlns and
dibenzo-furans. The owner was surprised by the absence of the other phenolics
mentioned, in Appnedix VII, and he was concerned by the presence of dioxins and
furans. Reading the text carefully, he discovered that the majority of the phenolic
compounds listed as hazardous constituents of the waste are actually
decomposition products of penta- and tetrachlorophenol. He also learned that
while the Agency had ruled out the presence of tetraohlorodibenzo(p)dioxin (TCDD)
in the listed waste (except where incinerated), they had not ruled out the
possibility that other chlorinated dioxins might be present: "... chlorinated dioxins
have been found in commercial pentachlorophenol and could therefore be expected
to be present in very small amounts in some wastes.11 Due to their extreme
toxicity and because his facility had historically used the commercial
pentachlorophenol with the highest concentration of dioxins and furans, the owner
thought it prudent to include a scan for dioxins in his waste analysis plan.
The owner found no further data in the Composition section to help him
narrow the list of phenolics; however, Table 6 gave a breakdown of organic
compounds found in different wood preserving plants (i.e., steam process vs.
Boneton conditioning), but only two phenolics were listed. A note in the text
highlights one of the limitations of using the Listing Document: The absence in
this table (Table 6) of certain components ... probably indicates that an analysis for
their presence was not performed rather than an actual absence of the component."
It should be kept in mind that the waste analyses in the Listing Background
Documents are not comprehensive and that they are based, as the Agency
acknowledges, on data available at the time. In the absence of more detailed
15-103
-------
waste-specific data, the owner decided to include pentaehlorophenol,
tetraohlorophenol, unsubstituted phenol, and the six listed decomposition-product
phenolic compounds in his waste analysis plan.
In reading the Listing Documents, the owner found useful information for
other phses of the RFI. In the Migratory Potential Exposure Pathways section, re
learned that pentaehlorophenol is highly bioaccumulative, with an octanol/water
partition coefficient of 102,000. Tetrachlorophenol, tri-chlorophenol, and
dichlorophenol are likewise bioaccumulative, with octanol/water coefficients of
12,589, 4,169, and 1,380, respectively. He also learned that the biodegradability of
pentaehlorophenol is concentration limited.
In Appendix B of the Listing Background Documents; Fate and Transport of
Hazardous Consituents, the owner found data sheets for six out of nine phenolic
compounds, also some for dioxins and furans. Information on water chemistry, soil
attentuacion, environmental persistence, and bioaccumulation potential were listed
along with chemical and physical properties such as solubility and density.
Case Discussion
Although the Listing Background Document did not provide the owner with
enough specific data to fully characterize his waste, it did help him refine the list
of monitoring constituents, alert him to the potential presence of dioxins, and gave
him physical and chemical waste characteristic data which could be useful in
predicting contaminant mobility.
15-104
-------
CASE STUDY 17: SELECTION AND EVALUATION OP A SOIL SAMPLING
SCHEME
Points Illustrated
o Sampling methodologies must be properly selected to most
appropriately characterize soil contamination.
o Statistical analyses can be used to evaluated the effectiveness of a
chosen sampling scheme.
Introduction
Selection of a sampling scheme appropriate for a soil contamination problem
is dependent on the objectives of the sampling program. A grab sampling scheme
may be employed, however, grab sampling can produce a biased representation of
contaminant concentrations because areas of gross contamination are most often
chosen for sampling. Random sampling can provide an estimate of average
contaminant concentrations across a site, but does not take into account
differences due to the proximity to waste sources and soil or subsurface
heteorogeneities. A stratified random sampling scheme allows these factors to be
considered and, thus, can be appropriate for sampling. Depending on the site,
additional sampling using a grid system may be needed to further define the areas
of contamination.
Facility Description
The example facility operated as a secondary lead smelter from World War II
until 1984. Principal operations at the smelter involved recovery of lead from
scrap batteries. Air emissions were not controlled until 1968, resulting in gross
contamination of local soils by lead participates.
Land use around the smelter is primarily residential mixed with
commercial/industrial. A major housing development is located to the northeast
and a 400-acre complex of single family homes is located to the northwest.
Elevated blood lead levels have been documented in children living in the area.
15-105
-------
Program Design/Data Collection
Initial soil sampling was conducted at the lead smelter and in the surrounding
area to document suspected contamination. Sample locations were selected based
on suspected areas of deposition of airborne lead and in areas where waste dumping
was known to have occurred. High lead concentrations were documented in
samples collected from these sources. Because data obtained in the exploratory
sampling program (grab sampling) were not adequate to delineate the areal extent
of contamination, a stratified random sampling scheme was developed.
Based on wind rose data and the behavior of airborne paniculate matter, a
sampling area was selected encompassing a 2 mile radius from the smelter.
Specific sampling sites were selected using a stratified random sampling scheme.
The study area was divided into sectors each 22.5 degrees wide and aligned so that
prevailing winds bisected the sectors. Each sector was further divided into
approximately one-tenth mile sections. A random number generator was used to
select first the direction and then the section. Random numbers generated were
subject to the following restrictions: two-thirds of the sites selected had to fall in
the major downwind direction; both residential and non-residential sites had to
exist in the sector; sampling sections were eligible for repeat selection only if they
were geographically within 1/2 mile from the smelter or if the section contained
both residential and non-residential sites. Sites that were biased towards lead
contamination from other than the lead smelter were not sampled (e.g., gas
stations and next to roads). A total of 20 soil sampling locations were selected, 10
at residences and 10 at non-residential sites such as schools, parks, playgrounds and
daycare centers.
Sample cores were collected using a 3/4 inch inner diameter stainles steel
•
corer. Total sample depth was 3 inches. A minimum of four and maximum of six
samples were collected at each sampling location within a 2 ft. radius. Cores were
divided into 1 inch increments and the corresponding increments were composited
from each depth to make up one sample. This approach provided data on lead
stratification in the top 3 inches of soil. All samples were analyzed for total lead.
15-106
-------
The results of the stratified random sampling indicated several acres with
over 2,000 ppm lead in the soil. To further define the extent of these areas, a grid
sampling plan was designed. Seven humdred and fifty foot increments were used.
The grid was oriented along the axis of the plume. Both residential and non-
residential areas were sampled. At each grid point, four 3 inch cores were
collected 30 m from the grid point in each major compass direction. The cores
were composited by depth as discussed above.
Program Results/Data Anayais
Analytical results from the soil sampling program indicated significant lead
contamination within the study area. Maximum concentrations observed were
2,000 ppm lead with a background level of 300 ppm. Krieging of the data from the
grid sampling plan was used to develop a contour map as shown in Figure 15-30.
Lead concentrations were highest northwest and southwest of the smelter.
Case Discussion
Because of the large area potentially affected by lead emissions,
development of a sequential sampling plan was necessary to determine the
maximum soil lead concentrations surrounding the smelter and the areas having
elevated concentrations. A grab sampling scheme was first used to confirm that
soil contamination existed. A stratified random sampling scheme was developed to
provide representative data throughout the study area. This type of sampling
allowed consideration of prevailing wind directions and the need to sample both
residential and non-residential areas. To further define areas of contamination, a
grid sampling plan was developed. From these data, contour maps were prepared
delineating areas with elevated concentrations.
15-107
-------
I 1 ' ' '
sad IsovaJves
• SMELTER
I I I I I I
ESTIMATED LEAD CONCENTRATIONS ( HQ/Q ) IN SOIL
SCALE
0 800
Feet
Figure 15-30. Contour Map of the Lead Concentrations in ppm Around the
Smelter
15-108
-------
CASE STUDY 18: SAMPLING OF LEACHATE FROM A DRUM DISPOSAL AREA
WHEN EXCAVATION AND SAMPLING OF DRUMS IS NOT
PRACTICAL
Points Illustrated
o It is not always possible to perform waste characterization prior to
establishing the RFI monitoring scheme since the waste may not be
directly accessible, as in the case of buried drums.
o When direct waste characterization is not practical, release monitoring
.should be performed for the constituents listed in Appendix B of Volume
I of the RFI Guidance.
Introduction
Insufficient waste characterization data existed for a former drum disposal
facility that was suspected of releasing contaminants into the subsurface
environment. Leachate within the disposal pit was sampled and analyzed for all
constituents listed in Appendix B of Volume I of the RFI Guidance. The resulting
information was used to determine the major waste constituents to be monitored
during the RFI.
Facility Description
The unit of concern was a pit containing an estimated 15,000 drums. Due to
poor record keeping by the facility operator, adequate information regarding the
contents of the drums was not available. It was also not known if the drums were
leaking and releasing contaminants to the environment. Since insufficient data
existed regarding the drum contents, it was not known what constituents should be
monitored in nearby ground and surface waters. Due to the risk to workers and the
potential for causing a multi-media environmental release, excavation and
sampling of the drums to determine their contents was not considered practical.
Instead, it was decided that leachate around the perimeter of the drum disposal pit
would be sampled to identify constituents which may be of concern.
15-109
-------
Program Design/Data Collection
In order to determine the physical extent of the buried drums a geophysical
survey was conducted using a magnetometer. Borings were located at positions
having lower magnetometer readings than surrounding areas in order to minimize
the potential for drilling into drums.
Soil borings were performed around the perimeter of the drum disposal pit, as
defined by the magnetometer survey. Drilling was accomplished using a hydraulic
rotary drill rig with a continuous cavity pump. Water was used as the drilling fluid.
In order to prevent surface runoff from entering and to control gaseous releases
from the borehole, primary and secondary surface collars were installed. These
consisted of 5-foot sections of 4-inch steel pipe set in concrete. A device to
control liquid and gaseous releases from the borehole was threaded onto the collars
to form a closed system (Figure 15-31).
Drilling was performed using a wireline operated tri-cone roller bit with a
diamond tipped casing advancer (Figure 15-32). Water was pumped down inside the
casing and out the drill bit, returning up the borehole or entering the formation.
The use of water to aid in drilling also helped reduce the escape of gases from the
borehole. Air monitoring showed no releases. Split-spoon samples were collected
at 5-foot intervals during the driuing and a leachate monitoring well was installed
at each boring location.
*
The soil and leachate samples were analyzed for the compounds contained in
Appendix B of Volume I of the RFI Guidance.
Progrn;" Results/Data Analysis
The leachate samples were found to contain high levels of volatile organic
compounds including 2-butanone, 4-methyl-2-pentanone, and toluene.
Concentrations were higher on the downgradient side of the pit.
15-110
-------
KCLLY ROD
KELLY
r-KELLY HOSC
•AU.-VALV1 O^CTATEO
THREADED STEEL
MUSBCT CASCCT
ENCLOSED RETURN
TANK (200 6AC)
THRCAOCD
(CMCRCCMCY SHUT-IN)
THRCAOCO *1.0. STCGL
SURFACE CASNC
NW CASNC
(N.T.S.)
Figure 15-31. Schematic Diagram of Gas Control'System Utilized at Pit
15-111
-------
WIREUNE CABLE
(N.T.S.)
OVERSHOT LATCHING
DEVICE
NW CASING
RETRACTABLE 2 15/16"
TRI-CONE ROLLER SIT
LOCKING INNER SUB
DIAMOND TIPPED CASING
ADVANCER (REAMING SHOE)
Figure 15-32. Schematic Drawing of Wireline Drill Bit and Reaming Shoe
15-112
-------
Case Discussion
Leachate sampling can be useful in determining whether buried drums are
leaking and in identifying the materials that are being released. This methodology
can be safer and more cost effective than excavation and sampling of individual
drums. It also identifies the more soil-mobile constituents of the leachate.
The data gathered in this case study were used in designing a monitoring
program, and the contaminants found were used as indicator compounds to link
downgradient ground water contamination to this waste disposal unit.
15-113
-------
CASE STUDY 19: CORRELATION OF CONTAMINANT RELEASES WITH A
SPECIFIC WASTE MANAGEMENT UNIT USING GROUND
WATER DATA
Point Illustrated
o Development of an effective ground water monitoring program can tie
releases of contaminants to specific waste mangement units.
Introduction
Documentation of a release from a specific waste management unit may
require the development of a comprehensive ground water monitoring program
coupled with an extensive hydrogeologic investigation. Determination of ground
water flow direction and horizontal and vertical gradients are necessary to assess
the direction of potential contaminant migration. Historical data on wastes
disposed in specific units can provide information on contaminants likely to be
detected downgradient.
Facility Description
This facility was previously described in Case Study 3. Chemicals were
manufactured at the 1000-aore facility for over 30 years. The facility produced
plastics including cellulose* nitrate, polyvinyl acetate, polyvinyl chloride and
polystyrenes, and other chemicals such as phenols and formaldehyde. Wastes
produced in the manufacturing processes were disposed on site in an unlined liquid
waste Impoundment and in two solid waste disposal areas. Readily combustible
materials were Incinerated in four burning pits. Ground water contamination has
been documented at the site. Figure 15-33 shows the facility plan and locations of
ground water monitoring wells.
The site Is located in a glacial valley and is adjacent to a major river. A
minor tributary runs through the southwestern portion of the facility and drains
into the river. Approximately 200 dwellings are located downgradient of the site.
15-114
-------
t
®
§
-o
«
9
£
"5
i
in
D
ffi
15-115
-------
Data Collection
Initial studies to assess the extent of ground water contamination began in
1981. Studies focused on ground water in the vicinity of various waste disposal
units. A limited number of monitoring wells were installed in 1983. These wells
provided general data on the direction of ground water flow and chemical
constituents that had entered the ground water. In 1984, a two-phased approach
was developed to define the areal and vertical extent of contamination and to
identify contaminant releases from specific waste manaement units. The first
phase involved the characterization of facility geologic and hydrogeologic
conditions using historical data, determination of the chemical nature of
contaminants in the ground water using existing monitoring wells, and development
of a contaminant contour map delineating the horizontal boundaries of
contamination. Based on this data, 33 soil borings were drilled in Phase 2. The
goals of the second phase were: 1) to detail subsurface geologic characteristics,
vertical and horizontal water flow patterns, contaminant migration, and site-
specific chemical contaminants; and 2) to install wells that would be used to
monitor contaminants being released from all units of concern at the facility.
Continuous split spoon samples were collected in each boring and headspace
analyses for volatile organic compounds (VOC) were conducted on each sample.
Chemical constituents were identified using a field gas chromatograph.
Confirmation^ analysis by GC/MS were conducted on selected samples.
Geotechnical analyses were'also conducted on the split spoon samples.
Chemical and hydrogeologic data (direction of flow, gradients) obtained from
the borings were used to select appropriate ground water monitoring well locations
and screen depths. Fifty-two (52) nested monitoring wells were installed at 25 *
locations upgradient and downgradient of each waste management unit, and near
the river and its tributary. Screen depths were determined by the depth of
maximum VOC contamination observed in the borings and the permeability of soil
layers.
15-116
-------
Data Analysis
Ground water contamination data from new wells coupled with historical
waste disposal data allowed releases from three specific waste management areas
to be defined. Sample analyses showed organic solvents in nearly all locations.
However, more unusual constituents associated with specific manufacturing
processes were detected in some samples, allowing them to be correleated with
releases from specific waste management units. The two situations below
illustrate how these correlations were accomplished:
1) PCBa detected in some samples were correlated with Solid Waste Disposal
Area #1. This area received construction debris, resins, plastics, metals,
drums, and PCB containing transformers. Records indicated that this unit
was the only location where transformers were disposed onsite. PCBs could
not be associated with any of the other waste management units.
2) The solvent dimethylformamide (DMF) detected in some samples was
correlated with Burning Pit B. It was discovered that the building that
housed this unit had been used to tint windshields and that DMF is a
component of the dye used in this process. DMF could not be tied to any of
the other waste management units. A leachfield in which waste dyes had
been disposed was discovered under the building and the contamination was
traced back to that source.
Case Discussion
An extensive hydrogeologic investigation of the facility was completed and,
in conjunction with historical data, was used to develop a comprehensive ground
water monitoring program. Placement of the monitoring wells, and screens was
essential in providing data that unequivocally linked contaminant releases to
specific waste management units and manufacturing processes.
15-117
-------
CASE STUDY 20: WASTE SOUKCE CHARACTERIZATION FROM
TOPOGRAPHIC INFORMATION
Points Illustrated
o Mapping of changes in site topography can support the selection of
locations for test borings and monitoring wells.
o This technique is best employed at sites where large volumes of waste
have been disposed of over several years.
Introduction
Topographic surveys conducted prior to and at different times during the
operation of a waste management facility can be used to help characterize the
vertical and horizontal extent of waste disposal areas. Because the resolution of
this technique is limited, it is most useful when large volumes of waste are
involved.
Facility Description
This facility is the same as discussed in case Studies 3, 4, and 18 above.
Topographic Survey
In 1984, a topographic survey measuring elevations in feet relative to mean
sea level was conducted for the areas shown in Figure 15-34. These elevations
were plotted on a map of appropriate horizontal scale and contoured in 2-foot
intervals. This topography was transferred to an existing site plan (horizontal scale
1" to 2000. Topographic maps from 1935 (showing the natural topography before
waste deposition) to 1960 (showing the topography in the earlier stages of the
facility operation) were compared to the 1984 map. By examining the changes in
elevations which occurred over time, contours were developed showing the
estimated changes in vertical and horizontal units of the liquid waste and solid
waste disposal areas.
15-118
-------
rS
I
if*
CO
15-119
-------
Results
From the analysis, it was apparent that the deepest portion of Solid Waste
Disposal Area (SWDA) No. 1 (Figure 15-34) was approximately 48 feet, and the
Liquid Waste Disposal Area (LWDA) was approximately 30 feet deep. The
horizontal limits of the disposal areas were also defined in part by this review, but
other field surveys provided more accurate information on the horizontal
boundaries of the waste disposal areas.
Case Discussion
Topographic surveys can provide useful information for characterizing
disposal areas. The results of these studies can facilitate the selection of
appropriate test boring locations, and may reduce the number of borings necessary
to describe the subsurface extent of contamination. It should be noted that
techniques such as infrared aerial photography and topographic surveying are
approximate in their findings. They are useful methods in the early phases of an
investigation, but do not replace the comprehensive characterization of the
environmental setting needed for the full investigation.
15-120
-------
CASE STUDY 21: SELECTION OF GROUND WATER MONITORING
PARAMETERS BASED ON FACILITY WASTE STREAM
INFORMATION
Points Illustrated
o Waste stream information can be used to identify . potential
contaminants. Knowing this, ground water monitoring parameters can
be selected appropriately.
o The number of constituents analyzed may be significantly reduced from
'Appendix VIII (40 CFR Part 261) constituents when waste stream
information is available.
Introduction
Regulated treatment, storage, and disposal facilities are required by RCRA
to identify all waste streams handled by the facility, volumes handled,
concentrations of waste constituents, and the waste management unit in which
each waste type is disposed. Ground water monitoring programs must be developed
to adequately monitor contaminant migration from each unit. Constituents to be
analyzed in the ground water monitoring program must be established prior to
sample collection. When waste stream data are not availble, a standard set of
monitoring constituents {Appendix VIII) are employed to fully characterize any
ground water contamination. Appendix VIII includes numerous constituents, so the
corresponding analyses are time consuming and costly to perform. Knowledge of
the waste streams managed by a facility simplifies the selection of indicator
parameters and monitoring constituents because potential contaminants and their
likely reaction and degradation products can be identified, thereby eliminating the
need for analyzing all Appendix VIII constituents.
Facility Description
The 600-acre facility has operated as a permitted Class II-I waste disposal
site since 1980. Solid waste management units occupy 20 acres of the site and
include four RCRA regulated surface impoundments and one container storage
15-121
-------
area. Until 1985, three non-RCRA regulated units (two surface impoundments and
one solids disposal unit) were used for geothermal waste disposal. However, the
two surface impoundments were replaced by a RCRA regulated landfill. RCRA
wastes managed by the facility include: metals, petroleum refining wastes, spent
non-halogenated solvents, electroplating waste water treatment sludge, spent
pickle liquor from steel finishing operations, and ignitable, corrosive, and reactive
wastes. Ground water monitoring wells have been installed downgradient of each
waste mangement unit.
Program Design
Prior to disposal, each load of waste received is analyzed in an on-site
laboratory to provide a complete characterization of waste constituents. Periodic
sampling of the waste management units is also conducted to identify waste
reaction products and hazardous mixtures. Even though the incoming wastes have
been characterized, the facility owner also analyzed initial ground water samples
from each monitoring well for all Appendix VIII constituents. The resulting data
were used to establish existing concentrations for each constituent and to select a
set of indicator parameters. The latter are used to identify migration of waste to
the ground water system. Table 15-15 includes a list of the indicator parameters
analyzed at the facility. Rationale for parmeter selection are included in this
table.
When an increase is detected in any of the indicator parameters, the facility
is required to monitor immediately for Appendix VIII constituents. Because the
facility accepts only a limited number of Appendix VIII constituents and initial
monitoring verified the absence of many constituents, this facility has been
allowed to reduce the total number of constituents monitored in ground water. The
process of constituent elimination is dependent on the actual wastes received by
the facility and physical and chemical properties of constituents that influence
their migration potential (e.g., octanol/water partition coefficients, solubility,
adsorptivity, susceptiblity to biodegradation).
15-122
-------
TABLE 15-15
INDICATOR PARAMETERS
Parameter
Total Organic Carbon (TOC)
Total Petroleum Hydrocarbons
Total Organic Halogen (TOX)
Nitrates
Chloride
Sulfides
PH
Total phenols
Criteria for Selection
Collective measure of organic substances
present
Indication of petroleum waste products
Halogenated organic compounds are
generally toxic, refractory, and mobile
Mobile contaminant, degradation product
of nitrogen compounds, mold, ammonia
Plating solution constituent, highly
mobile in ground water. Early indicator of
plume arrival
Toxic, biodegradation by product, strong
reducing agent, may immobilize heavy
metals
Good indicator of strongly acidic or
alkaline waste leachates close to sources
Collective measure of compounds likely to
be in waste. Even small concentrations
can cause olifactory problems following
water treatment by chlorination
15-123
-------
Non-halogenated solvents have relatively low partition coefficients
(Kow: benzene = 100; toluene = 500) and are not readily retained by soils.
Conversely, polycyclic aromatic hydrocarbons* constituents of petrochemical
wastes, have very high partition coefficients (e.g., chrysene = 4x105) and are
generally immobile in soils. Migration rates of metals are also influenced by the
exchange capacity of the soil. Different metal species are retained to different
extents. Following an assessment of the migration potential of each waste
constituent, the need for analysis of that constituent can be prioritized. Two
waste types never accepted at the subject site include halogenated solvents and
pesticides. Therefore, constituents found in these wastes would be de-emphasized.
Case Discussion
Waste stream information was used to determine appropriate indicator
parameters and monitoring constituents. The use of the existing initial ground
water quality data and the incoming waste analyses allowed for prediction of
contaminants of concern in ground water and reduced the number of constituents
requiring analysis.
15-124
-------
CASE STUDY 22: USING WASTE REACTION PRODUCTS TO DETERMINE AN
APPROPRIATE MONITORING SCHEME
Point Illustrated
o It is important to consider possible waste reaction products when
designing a monitoring plan.
Introduction
Volatile organic priority pollutants have been detected in ground water til
across the country. These compounds, widely used as solvents, are generally
considered environmentally mobile and persistent. Increasing evidence* however*
indicates that chlorinated solvents can be degraded under anaerobic conditions by
reductive dehydrochlorination. The sequential removal of chlorine atoms from
halogenated 1 and 2 carbon aliphatic compounds results in formation of other
volatile priority pollutants which can be detected during investigations of solvent
contamination.
Facility Description
The facility is a small municipal landfill sited on a former sand and gravel
quarry. In addition to municipal wastes, the landfill accepted trichloroethane and
tetrachloroethene contaminated sludge from a local fabrication plant until 197S.
In 1983, a municipal well located downgradient from the landfill tested positive for
dichloroethane, dichloroethene isomers, and vinyl chloride. This prompted the city
to investigate the cause and extent of the problem.
Site Investigation
According to records kept at the landfill, some of the compounds found in the
municipal well were not handled at the facility. This prompted the city to request
that a monitoring program be developed to identify another facility as the source
of the well contamination. A careful search of the city records, however, failed to
indicate a credible alternative source of the compounds. Suspecting that the
landfill was the source of the well contaminants, five monitoring wells
15-125
-------
were installed (Figure 15-35) and water samples were analyzed for halogenated
compounds using EPA Method 601. The results, given in Table 15-16, show an
increase in degradation products of trichloroethane and tetrchloroethene with
increasing distance from the landfill. Using these data, supported by hydrogeologic
data from the monitoring wells, the municipal landfill was shown to be the source
of the observed contamination.
Table 15-16
RESULTS OF MONITORING WELL SAMPLING
WELL NUMBER (SEE FIGURE 2-34 FOR WELL LOCATIONS)
1 2345
Chlorinated Ethanes
(1) Trichloroethanes 10(3) 68 ND(4) ND ND
(2) 1,1-Dichioroe thane 71 240 130 11 13
1,2-Dichloroethane ND 12 21 NO ND
Chloroethane ND 21 18 160 ND
Chlorinated Ethenes
(1) Tetrachloroethene 80 13 ND ND ND
Trichloroethene 12 100 62 ND ND
(2) 1,2-Dichloroethenes - ND 990 950 150 ND
1,1-Dichloroethene ND ND ND ND ND
Vinyl Chloride ND 120 59 100 ND
(1) Parent Compounds (3) All Concentrations In Micrograms/L
(2) Degradation Products (4) ND - < 10 Micrograms/L
Case Discussion
Based on the compounds found in the municipal well, the city had argued that
the municipal landfill could not be the source of the contamination. If this
reasoning had been followed, then a system of monitoring wells might have been
inappropriately designed in the attempt to find an alternate source of
15-126
-------
r^~ __mf> _Prop«rty Line
Approxiaate Scale 1"-500'
General
Direction
Of
Ground W»c«r
Flow
.Municipal
Well
NOTE: Locations of nearby industrial
facilities not shown.
Figure 15-35. Site Map and Monitoring Well Locations
15-127
-------
the contamination. Instead, after carefully researching local industries, it was
determined that the landfill was the most reasonable source of the pollution and
that the observed well contaminants were probably degradation products of the
landfilled solvents. The progressive dehalogenation of chlorinated ethanes and
ethenes, as listed in Table 15-16, is commonly encountered in situations where
chlorinated solvents are subjected to anaerobic conditions (Wood, 1981). Different
degradation reactions may occur when pesticides are subjected to acidic or alkaline
conditions or biological degradation. Therefore, it is important to keep reaction
products in mind when designing any monitoring scheme or interpreting
contamination data.
Reference
Wood, P.R., R.F. Lang, I.L. Payan, and J. DeMarco. 1981. Anaerobic
Transformation, Transport and Removal of Volatile Chlorinated Organics in Ground
Water. First International Conference on Ground Water Quality Research, October
7-10, 1981, Houston, Texas.
15-128
-------
CASE STUDY 23: USE OF AERIAL PHOTOGRAPHY TO IDENTIFY CHANGES
IN TOPOGRAPHY INDICATING WASTE MIGRATION ROUTES
Points must rated
o Aerial photographs can be used to obtain valuable data on facility-
related topographic features including type of waste disposal facility,
distance to residences and surface waters, adjacent land use, and
drainage characteristics.
• •
o Detailed interpretation of aerial photographs can identify actual and
potential waste migration routes, and areas requiring corrective action.
Introduction
Stereoscopic pain of historical and current aerial photographs were used to
assist in the analysis of waste management practices at a land disposal facility.
Stereo viewing enhances the interpretation of aerial photographs since vertical as
well as horizontal spatial relationships can be observed, and since the increased
vertical resolution aids in distinguishing various shapes, tones, textures, and colors
within the study area. Typical items that should be noted include pools of
unexplained liquid that could indicate seepage from buried materials which could
enter drainage and migrate off site. Soil discoloration and vegetation damage or
lush vegetation growth can be indicative of how materials are being handled on site
and of possible off-site contaminant migration.
Facility Description
The site is an active land disposal facility which receives bulk hazardous
waste including sludges and contaminated soil for burial, and liquid wastes for
disposal into solar evaporation surface impoundments. Operations at the facility
began in 1969. Historical and current aerial photographs were reviewed to assess
waste management practices and to identify potential contaminant migration
pathways requiring further investigation and corrective action.
15-129
-------
Data Collection and Anavais
Low altitude color aerial photographs of the facility (scale = 1:8400) were
obtained in October 1983 and Feburary 1984. The photos were interpreted by an
aerial photo analyst at the U.S. EPA Environmental Monitoring and Support
Laboratory at Las Vegas, Nevada. Figure 15-36 shows the analyzed photograph.
The interpretation code is given in Figure 15-37. Analysis of the photograph
indicates several areas of seepage at the base of the surface impoundments. This
seepage indicates that either the impoundments are not lined or the liners have
failed. Drainage from the western portion of the facility which contains most of
the impoundments flows into a drainage reservoir formed by a dam across the main
drainage. Drainage from the northeast portion of the facility where seepage was
also observed appears to bypass this reservoir and enter the main drainage which
flows offsite. Besides possible surface contamination, this seepage also indicates
potential subsurface contamination.
The aerial photo obtained in February 1984 (Figure 15-38) indicates the
continued existence of seepage from the surface impoundments. There is evidence
of possible discharge from the drainage reservoir to a stream channel, as a pump
and piping were observed. Additional material in the solid waste disposal area has
altered the drainage pattern. At the south end of this area, seepage is evident in
association with damaged vegetation. Drainage from this area enters a drainage
system and appears to be diverted offsite.
•
Case Discussion
Analysis of aerial photographs of the land disposal facility enabled
investigators to identify potential contaminant sources and migration pathways.
This information was used by investigators to identify areas for surface water,
sediment, soil, and subsurface sampling. Most importantly, it identified areas
requiring corrective action including impoundment liners and the facility drainage
system.
15-130
-------
'£•",* .-7'\ ^.x^ /V7 / '
^m^M Iffi
KifflSMtS^
3rv*yt.-'Jl
ft!-,*'-: «
Figure 15-36. October 1983 Aerial Photo of Land Disposal Facility
15-131
-------
INTERPRETATION CODE
eOUNQABUS AND LIMITS
•_»_i_ MNCID «TI •OUNDANV
«— __ UNMNCI0 «T1 •OUNOAHV
I I • I I M NCf
— -— MOMNTV UNC
— » r— «*Tt/Acem WINT
- ttCTION COHNIM
OlHICTlON
••— •• INOtTIIMMMATI OHAINAOt
THANSKmTATlON/UTILITV
SSSSS VI HICLf ACCIS
I i I I IUILWAV
........ MHUNI
— —— POWIHUNf
SITt MATURES
iHHimiiu 01 KI
(TANOIMO LIQUID
«. STANDING LIQUID
ISMALU
OfXCAVATlON »IT
(IXTINSlVfl
MOUND CO MATIHIAL
IfXTINSIVtl
MM MOUNOIO MATfNIAt
(SMALL)
CM CMATIS/VOXIS
OM OMUMS
MT MONIZOMTAL TANK
FT MfSSUM TANK
VT VIMTICAL TANK
CA CLIAttfO AHIA
OG OKTUMIO OMOUNO
fL PILL
IM IMPOUNOMINT
US LAOOON
00 OWN DUMP
Of OUTFALL
SO SLUOCI
ST STAID
SW WLIO WAST!
Tft THfNCM
WO NASTI OlVOSAL AMIA
Figure 15-37. Aerial Photo Interpretation Code
15-132
-------
Figure 15-38. February 1984 Aerial Photo of Land Disposal Facility
15-133
-------
CASE STUDY 24: IDENTIFICATION OF A GROUND WATER CONTAMINANT
PLUME USING INFRARED AERIAL PHOTOGRAPHY
Point Illustrated
o Infrared photography can assist in identifying plumes and in locating
monitoring wells by showing areas of stressed vegetation and
contaminated surface water.
Introduction
Infrared aerial photography can assist in identifying contaminant plumes at
sites where little or no monitoring has been conducted. By identifying areas of
stressed vegetation or contaminated surface water, it may be possible to focus on
contaminant discharge points and roughly define the extent of a release.
Hydrogeologic investigations and surface water sampling can then be performed to
further characterize the release. Considering the expense of drilling and installing
wells, infrared photography offers the potential to increase the efficiency of a -.
sampling program.
Facility Description
•*
The facility is a municipal solid waste landfill which has served a population
of 22,000 for 30 years. The facility coven an area of 11 acres, holding an
estimated 300,000 tons of refuse. The majority of waste in the landfill was
generated by the textile industry. Until July 1978, the facility was operated as an
open dump with sporadic management. City officials indicated that original
disposal occurred in open trenches with little soil cover. After July 1978, the
facility was converted to a well-operated sanitary landfilL Figure 15-39 shows the
facility.
Geologic Setting—
The landfill is located on a sandy to silty till varying in thickness from 23
feet at the hill crest to 10 feet on the side slope. A swamp is present at the base
of the hill at about 255 feet above sea level. There is a dam at the southern
drainage outlet of the swamp, a distance of 2,500 feet from the landfill. Ground
15-134
-------
O BACKGROUND WELL 8
METAL
BACKGROUND WELL A
LIMIT OF REFUSE 7/78
N
TREE \
KILL /^ v ,
AND
STRESS
SCALED. (APPROXIMATE)
0 332' 664'
• WATER
O WELL LOCATION
D VECETATION SAMPLING
STREAM
• STREAM SAMPLING POINT
• HOUSING
Figure 15-39. Facility Plan
15-135
-------
water is approximately 20 feet below the surface at the crest of the hill, while on
the slope it is at 6 feet. The swamp at the foot of the hill is the surface expression
of the ground water (Figure 15-40).
Aerial Photography and Sampling Program
Figure 15-41 shows the infrared aerial image of the site. The landfill
corresponds to the light area in the northwest portion of the photograph (Figure
15-40). The dark area to the south of the site is stressed vegetation, and the light
area within it is contaminated swamp water. The 33-acre area of tree kill and
stress is clearly visible. Plants under stress may be detected by infrared
photography because of changes in infrared reflectance.
Ground water monitoring wells and vegetation sampling points are shown in
Figure 15-39. Data collected from the wells indicated elevated levels of
chromium, manganese, iron, and total organic carbon (TOG). Table 15-17 lists the
average concentrations of the parameters tested. The vegetation study indicated
an accumulation of heavy metals.
Case Discussion
The vegetative stress apparent in the infrared photography was confirmed by
the data from the ground water and vegetation sampling. However, the site
requires further characterization to determine vertical boundaries of
contamination and to assess the potential for impact beyond the present area of
stressed vegetation.
It should be emphasized that infrared photography is not a substitute for
hydrogeologic characterization. However, it is a useful tool for identifying areas
of stressed vegetation that may be associated with releases from waste disposal
sites.
15-136
-------
V
£
o
v
S
u
•s
^N
1
«
i
I
in
£
S,
ee
u
§
§
c
(9
U
J
U
(0
K
O
e
u
15-137
-------
15-138
-------
l/t
O
z
o
r^ Z
in o
UJ (j
a z
UJ
UJ
s
QC
UJ
O
UJ
a
•o
u
8
u
a
00
u
u
2
re
Z
c
5
4>
0.
6
H
o
z
z
z
z
•-
H-
o
0
00
-.
in
0
o
00
ON
^
»N
O
Ot
in
00
^
o
rx
(N
S
—
^
^
^.
««•
O
V
c
3
0
^J
w
00
ON
<•"<
H-
in
03
fN
00
0
o
o
8
f*N
S
SO
in
»N
"*
00
00
o
-
o
§
o
in
o
^
•-
ON
•"
O
(N
V
"*
(N
0
O
o
00
_
^
ON
rs.
m
o
0
o
V
o
0
V
in
(N
§
^
^
ife
V
^
00
in
H-
q
UO
00
o
o
o
(N
r^
|x
in
00
0-1
SO
*.
***
00
o
in
o
(N
>oo
c ^£
o ~z
Q.-O
Si
2 o
a* a>
2 o«
2 £
._ *
15-139
-------
CASE STUDY 25: PRESENTATION OF DATA COLLECTED DURING FACILITY
INVESTIGATIONS
Point Illustrated
o Techniques for presentation of data for facility investigations involving
multimedia contamination.
Introduction
Data acquisition and interpretation are integral parts of facility
investigations. Depending on the size, complexity, and hazards posed at a
particular site, significant quantities of meteorologic, hydrologic, and chemical
data can be collected. To make the best use of these data, they should be
presented in an easily understood and meaningful fashion. This case study focuses
on widely used and easily implemented graphical techniques for data presentation.
Site Description
The site is a former copper smelter that ceased operation in the early 1980's.
During the operation of the smelter, large quantities of mine tailings were slurried
to tailings ponds that remain today (Figure 15-42). The tailings contain high solid
phase concentrations of inorganic contaminants such as copper, zinc, lead,
cadmium, and arsenic. In the Smelter Hill area, flue dust and stack emission
deposition have contaminated surficial soils. Numerous other facilities were
operated at the complex including an experimental plant designed to leach copper
using ammonia. The copper leach plant is shown in Figure 15-43. Three disposal
ponds (I, II, and III) received wastes slurried from the plant.
As a result of smelting and waste disposal practices, multimedia
contamination of ground water, surface water, and soils has occurred. Also,
episodes of air contamination have been documented due to entrainment of tailings
during windy periods.
15-140
-------
\
M
^J
C
o
eu
8.
PM
"3
"2
•g
«
V
*rf
w
t*
V
*rf
*3
E
CO
«
a
c
•
c*
^<
I
in
i-»
£
g>
£
15-141
-------
15-142
-------
Field Sampling and Data Collection
Data collection activities at this site were comprehensive. Over 100,000
pieces of data were collected in the categories shown in Table 15-18.
Data Presentation
This section illustrates a number of graphical techniques that can be used to
present data from facility investigations. Graphical presentations are useful for
the following general purposes:
o Site feature identification, source identification, and mapping;
o Hydrologic characterization; and
o Water quality characterization.
For large sites, aerial photography is often very useful for accurately pinpointing
the locations and boundaries of waste deposits, and for establishing time variability
of site characteristics. Figure 15-43, for example, was developed from aerial
photographs at a 1:7800 scale. Types of information obtained by comparing this
photograph to one taken 10 years earlier include:
o Pond III was originally constructed earlier than Ponds I and II, and was
not lined. Ponds II and III were lined.
o The red sands (a slag deposit) shown in Figure 15-43 are present only
north of the railroad tracks. Earlier photographs showed that the red
sands extended to Highway 10A, but were leveled and covered with
alluvium during construction of the copper leach plant.
This type of photographic information is valuable for locating waste deposits,
estimating quantities of wastes, and determining their proximity to sensitive areas.
15-143
-------
Table 15-18
SUMMARY OF DATA COLLECTED
Category
Ground Water
Surface Water and
Sediment
Alluvium*
Soil'
Tailings*
Slag and Flue Ousta
Miscellaneous
Parameters
Water level elevations, piezometric heads
Concentration of A1, So, As, Ba. Be, Bo, Cd,
Ca, Cr, Co, Cu, Fe, Pb, Mg, Mn, Hg, Mo, N1. K,
Se, Ag, Na, Sn, V, Zn, P, Cl, F, SOi, pH, Oi,
EC, Eh, Alkalinity, TDS,
Flow rates, bed particle size distributions,
suspended solids concentrations, dissolved
concentrations of same Inorganic parameters as
ground water
Moisture content, soil pH, EC, Sb, As, Cd, Cu,
Fe, Pb, Mn, Se, Ag, Zn, part1c1e-s 1 ze
distribution
Cd, Cu, Fe, Pb, Mn, N1, Zn, Sb, As, Cd, Cr,
Hg, Se, Ag, Zn, particle-sire distribution,
Eh, S, TOC
Sb, Ar, Be, Cd, Cu, Fe, Pb, Mn, Ag, Se, Zn,
particle size, moisture, pH, EC, sulfur,
carbonate
Sb, As, Cd, Cu, Fe, Pb, Mn, Se, Ag, Zn, S04,
EC, pH, alkalinity
Meteorology, aerial photographs and other
photographic documentation, well log data,
surface topography, volumetric surveys of
waste piles
a£lement data are solid phase.
15-144
-------
For sites with complex hydrologic interaction, it is often helpful to
graphically represent the flow system. Figure 15-44 illustrates the surface water
system at the site. The diagram is useful because it shows the hydrologic
interconnections of the drainage system.
For the ground water system, flow direction and velocities provide
information needed for solute transport predicitons. This information is generated
by plotting water levels on a site map, and then drawing contours through points of
constant elevation. An example is shown in Figure 15-45. Because the contours
form a regular pattern, they are easily drawn by hand. However, computer-based
contour packages exist that could be used to plot more complicated contour
patterns.
Inferred flow directions are also shown in Figure 15-45. From a knowledge of
the water surface gradient and aquifer permeability, the Darcy and seepage
velocities can be calculated, as shown in the upper left hand corner of the figure.
A seepage velocity of 80 m/yr is calculated, for example, which means that
approximately 125 yean would be required for conservative solutes to move across
the site.
Water quality data can be presented as shown in Figure 15-46. This figure
shows the, spatial distribution of calcium, sulfate, and TDS at key surface water
stations. This data presentation method provides a synoptic view of these
parameters.
Time series plots are useful for showing temporal variations in water quality.
For example, time trends of SO4 at three ground water locations are shown in
Figure 15-47. Well 19 is slightly downgradient from the source, and the high SOJ
levels reflect that the well is receiving solutes generated within the source. Wells
26 and 24 are further upgradient, and reflect better water quality conditions. The
plot indicates that variability between stations generally is more significant than
time variability at a given location. One exception is at well 24 where a temporary
increase in sulfate levels was noted in 1975-76.
15-145
-------
UNCAGED
DIVERSIONS
RANQUS
CREEK
HILL
CREEK
GOLDEN
CREEK
NEW i
LIME |
DITCH !
SOUTH
DITCH
OLD
LIME
DITCH
'DECANT '
IDITCHIS/1"
I 7
BYPASS
PONDS
~]
SEWAGE
DITCHES
NORTH
DRAIN
DITCH
COLD
CREEK
CAM DINER
OITCM
UNCAGED
DIVERSIONS
GREEN
RIVER
Figure 15-44. Schematic of Surface Water System
15-146
-------
i
0)
as
§
S
m
o
E
ee
•g
1
O
to
15-147
-------
^
s
28282§ae^
D
*
8828218°
CVDH) MOUVUN33N09
rVOK) NOUVM1N19N09
fVtWl NOUTH1N39M03
15-148
-------
2400i
2000-
= 1600-
«*
I*
O*
W 1200-
800-
400-
• Well 19
o Well 24
* Well 26
1974 1975 1976 1977 1978 1979 1980 1981 1982 1983 1984 1985
Year
Figure 15-47. Changes In Sulfate Over Time at Selected Wells
Located within the Site
15-149
-------
To identify leachate and soil interactions beneath a waste site, trenches may
be dug. The trench walls are then logged and photographed. Detailed sampling
may be done at closely spaced intervals to confirm that reactions such as
precipitation have occurred. Figure 15-48 shows a cross-section of a tailings
deposit that was developed based on a trench excavated through the tailings into
the underlying alluvium. The plot shows the demarcation between wastes and
natural alluvium.
Figure 15-49 shows the details of the chemical composition of one borehole
through the tailings and into the underlying alluvium. The chemical composition is
shown to vary significantly with depth. These types of plots contain a wealth of
chemical information that can help to explain the geoohemical processes operative
in the tailings. Figure 15-49 also shows the marked contrast between the
composition of the tailings (in the top 16 feet) and the underlying alluvium.
Summary
The graphical presentations illustrated in this case study are a few of the
many techniques available. With the proliferation of graphical packages available
on microcomputers, scientists and engineers have a wide range of tools available
for data presentation. Some of these tools are summarized in Table 15-19.
15-150
-------
yi':V'"'v\X$^^ I "^** ^-V/.'--'!
..N./.-V^:..'4$$2 f ^[2 i?'.--: 1
k* * •* * '^^L^^Xk c ^ ^ **• ^ -.«-1
••-.-.'•'T^^^OOujS ^r^S •.•.•.•.;.-•
e —'
5
i
l!
•
I!
H
Wl
i
15-151
-------
S*fS
w
II
* ? J * S (
'* si *»c
'• I
.1
I
t
!'
1 t 1!S*«
f
t
I
!
•
l
i "
z
:ttt
•e s:*s«
!!
i*.
'* ss ttt
—
09
T3
4)
4->
o
—
15
09
en
01
II
I!
2 «
O
O
5
O.
4)
Q
15-152
-------
Table 15-19
TYPICAL METHODS FOR GRAPHICALLY PRESENTING DATA COLLECTED
DURING FACILITY INVESTIGATIONS
Data
Meteoroloqlc Data
Wind speed and direction
A1r Temperature
Precipitation
Evaporation
Surface Water Data
Flow rates
Water quality
Graphical Presentation Methods
Geohydroloqlc Data
Ground Water Data
Miscellaneous
Wind rose showing speed, direction, and percent of
observations for each 10° Increment
Bar chart, by month
Bar chart, by month
Bar chart,"by month
• Hydrographs; distance profiles* cumulative
frequency distributions, flood frequency plots
• Hydrologlc network depiction and water budgets
• TrUlnear diagram
• Stiff diagrams
• Contour showing vertical concentration or temp-
erature variability 1n two deep water bodies
• Time history plots showing dally/annual
variability
• Bar charts of major catlons/anlons or contami-
nants at multiple locations shown on a single
map
Geologic map of site and vicinity
Strat1graph1c cross-sections of site 1n direction
of and perpendicular to ground water flow
Well logs
Cross sections at waste deposits
Solid phase chemical analyses by depth at borings
throughout waste deposits and Into alluvium
Water level contours
Flow directions and velocities
Time history of water table at Important locations
Stiff diagrams
TrlUnear diagrams
Contaminant plumes, showing Isopleths
• Figures with Important site features, Including
waste sources, storage ponds, disposal areas,
buildings, sampling locations, well locations
• Operational aspects for special sampling equipment
(e.g., lyslmeters)
15-153
-------
CASE STUDY 26: USE OF QUALITY ASSURANCE/QUALITY CONTROL
(QA/QC) AND DATA VALIDATION PROCEDURES
Points Illustrated
o A comprehensive field and laboratory QA/QC program is necessary for
assessing the quality of data collected during an RFI.
o Timely validation of laboratory data can uncover problems correctable
by reanalysis or by resampling, thus preventing data gaps.
Introduction
A company in the mining and smelting industry sampled domestic wells and
surface soils in the vicinity of a tailings pile to monitor possible leaching of metals
into the aquifer and possible soil contamination due to wind-blown dust. Because
the data would be used to assess corrective measures alternatives and to produce a
health and environmental assessment, the company chose to conduct both its
sampling and analysis efforts under a formal QA/QC Project Plan and to subject all
laboratory data to a rigorous data validation procedure. The overall goal of this
effort was to produce data of sufficient quality to withstand the scrutiny of
litigation.
Facility Description
At this facility, a tailings pond had received smelter waste for many years.
Local water supply wells were potentially at risk due to percolation of water
through the pile and possible leaching of heavy metals. Local surface soils in
nearby residential areas (e.g., yards, public playgrounds) were also subject to
contamination from wind-blown dust originating from the pile during dry windy
weather.
Sampling Program
Before sampling began, a set of documents were drafted following U.S. EPA
guidelines (U.S. EPA 1978, 1980a, 1980b, 1981, 1982, 1985a, 1985b) that specified
15-154
-------
in detail sampling sites and parameters to be measured, field and laboratory
procedures, analytical laboratory protocols, and all field and laboratory QC checks
including frequencies, and corrective actions. The important elements of each
document are described below.
Standard Operating Procedures (SOPs)—
This document contained step-by-step procedures for the following items:
o Calibration, operation, and maintenance of all instruments used in the
field and field laboratory.
o Equipment decontamination.
o Ground water sampling and soil compositing and sampling.
o Use of field notebooks and document control.
o Sample packaging, shipping, and chain-of-custody.
Field Operations Plan (FOP)—
This document included the following:
o Rationale for choice of sampling locations, sampling frequency, and
analytes to be measured
o List of sampling equipment and SOPs to be used for each sampling
event.
o List of field QC checks to be used and their frequency for each
sampling avent.
o Health and safety issues and protective measures for field personnel.
o Sampling schedule.
15-155
-------
Laboratory Analytical Protocol (LAP)—
This document included the following:
o Sample size, preservation, and analysis protocol for each analyte.
o List of laboratory QC checks, QC statistics to be calculated and their
control limits, and corrective actions for QC checks outside control
limits.
o Detailed list of deliverable documents and their formats.
o Procedures for sample custody, independent audits, and general
laboratory practices.
QA/QC Project Plan (QAPP)-
This document gathered into one place the overall data quality objectives for
the sampling and detailed QC procedures needed to attain those objectives.
Included were:
o Quality assurance objectives in terms of precision, accuracy,
completeness, comparability, and representativeness.
o Procedures for the screening of existing data.
o Data management, reduction, validation, and reporting.
o Overview of both field and laboratory QC checks and their frequencies,
control limits, and corrective actions.
o Data assessment procedures.
15-156
-------
Results
Five surface soil samples were taken in high traffic areas of two playgrounds
and three residential yards. Five tap water samples were collected at two public
drinking fountains at the playgrounds and at the three private residences. The
analysis results, as received from the laboratory, are shown in Table 15-20. The
data indicated that a soil hot spot existed for cadmium, that elevated lead
occurred at all five soil stations, and that all of the domestic wells were
contaminated with, mercury.
The laboratory data package was subjected to a thorough data validation, as
detailed in the QA Project Plan. The following information and QC results were
checked by examination of original documents or photocopies of the documents.
Sampling, Sample Shipping, Chain-of-Custody—
Copies of field and field laboratory notebook pages were examined to insure
that ail SOPs were correctly followed, that there were no notations of anomalous
circumstances (such as sample spillage) that may have affected analysis results,
and that the samples were correctly preserved, packaged, and shipped. Copies of
all chain-of-custody forms, bills-of-lading, and sample analysis request forms were
examined *o insure that chain-of-custody was not broken and that samples arrived
intact at the laboratory.
Laboratory Raw Data—
The QAPP had specified that one of the deliverables from the laboratory was
copies of all instrument readouts and laboratory notebook pages. The digestion raw
data were checked to insure that no holding time violations had occurred. This is
important for mercury because the holding time is only 28 days for aqueous
samples.
All raw calibration data were recalculated and tested against instrument-
calculated sample results. Recoveries of calibration verification standards and
continuing calibration standards were checked to insure that all instruments were
15-157
-------
Table 15-20
RESULTS OF ORIGINAL SURFACE SOIL AND TAP WATER ANALYSES
Sample8
SOIL-1
SOIL-2
SOIL-3
SOIL-4
SOIL-5
WATER- 1
WATER- 2
WATER- 3
WATER- 4
WATER- 5
Cd
14
7
<20C
19
1200
<50
<50
<50
<50
<50
Cu
6200
2400
720
6SO
1080
NA
NA
NA
NA
NA
Pb
800
400
530
350
460
<30
<30
<30
<30
<30
Hq
NAb
NA
NA
NA
NA
1.5
1.3
1.0
1.4
1.2
Zn
1200
190
70
350
420
NA
NA
NA
NA
NA
aSo1ls 1n units of mg/kg, water 1n ug/L.
Not analyzed.
Undetected at detection limit shown.
15-158
-------
correctly calibrated, were not drifting out of calibration, and were correctly
calculating raw analysis results.
Final analysis results were recalculated from raw data using dilution and
digestion factors, as summarized in the lab notebooks, and compared to the data
summary sheets. No transcription errors were found. However, the cadmium
result for SOIL-5 contained a calculation error, and the correct final result was 12
mg/kg instead of the 1200 mg/kg reported.
Laboratory QC Checks—
The QAPP had specified that the laboratory had to analyze pre-digestion
duplicates and spikes, U.S. EPA laboratory control samples, and reagent blanks.
The laboratory QC results are summarized in Table 15-21 and indicated accuracy
and precision well within U.S. EPA guidelines. The mercury preparation blank also
indicated that the tap water results were not due to laboratory digestion reagents
or procedures.
Field QC Checks-
As specified in the QAPP and FOP, the following field QC samples were
included with each of the soils and tap water samplings: bottle blank, field blank,
standard reference material (SRM), triplicate, and an interlaboratory split to a
"reference" lab. The results are summarized in Table 15-22.
Although no U.S. EPA control limits or corrective actions exist for field-
generated QC checks, the results of their analysis can aid in the overall assessment
of data quality. The triplicate, SRM, and interlaboratory split analyses indicated
good overall analysis and sampling precision and accuracy. The field blanks
indicated the possibility of mercury contamination from one of the four possible
sources: the pre-cleaned bottles, the preservation reagent, the distilled water used
in the field, or an external contamination source such as dust. The high positive
mercury result in the water bottle blank eliminated all of these sources except the
first because the bottle blanks remained sealed throughout the sampling effort.
15-159
-------
Table 15-21
LABORATORY QC RESULTS
Duplicate RPDa (I) Spike Recovery1* (%) LCS
Soil
Water
Analyte
Cd
Cu
Pb
Hg
Zn
SOIL-2
13
5
14
NA
7
HATER- 4
NCf
NAh
NC
NC
NA
SOIL-2
100
93
no
NA
85
HATER- 4
98
NA
92
103
NA
(X)
101
97
106
NA.
99
Blank0
<509
<100
<200
NA
<150
Blank6
<50
NA
<30
<0.20
NA
aRPD » relative percent difference » (difference/mean) X100. Control limits *
±351 for sol Ids and ±201 for aqueous samples.
bSP1ke Recovery - (spi^sample result) - (sample result?
Control limit • 75-125X.(spike added)
LCS « laboratory control sample. Control Hm1t » 90-1101.
mg/kg.
eug/L.
NC • not calculated due to one or both concentrations below detection limit.
^Undetected at detection limit shown.
NA • not analyzed.
15-160
-------
Table 15-22
FIELD QC RESULTS
Analyte
Cd
Cu
Pb .
Hg
Zn
Triplicate
CV1 (X)
SOIL-1 WATER- 1
22
3
7
NA
1
NCh
NAj
NC
18
NA
SRM
Recovery (X)
BCSS-lc
83
94
97.
NA
110
U.S.EPAQ
105
NA
101
103
NA
Interlab.
RPDe (X)
S151L-1
-12
0
14
NA
24
WATER- 1
NC
NA
NC
19
NA
Field,
Blanks'
SOIL
<501
<100
<200
NA
<150
WATER
<50
NA
<200
1.1
NA
Bot1
Blar
SOIL
<0.5
<1
<0.5
NA
-------
The laboratory was immediately called, and upon personal inspection, the
laboratory manager discussed the remnants of a. broken thermometer bulb in the
plastic tub used to acid-soak the bottles. An unused bottle from the same lot and
still at the laboratory as well as two bottles washed in previous lots were analyzed.
The bottles previously washed contained no mercury (above detection limits), and
the bottle from the same lot as used in the sampling effort contained 0.75 ug. The
water mercury data were rejected, and a second sampling effort using new bottles
was conducted. All of the new samples contained no mercury (above detection
limits).
Discussion
This case study demonstrates the need for the establishment of a formal
QA/QC program that not only specifies field QC protocols but also incorporates
thorough data package validation. In this instance, a potential hot spot was found
to be only a calculation error, and mercury contamination of domestic well water
was found to be only an artifact of using contaminated sample containers. In the
latter case, timely QA/QC review allowed for a speedy resampling effort which
could be done at this site. In many situations, resampling is not possible, and thus
QA is even more important.
References
U.S. EPA. 1978 (revised 1983). NEIC policies and procedures.
EPA-330/9-78-001-R. U.S. EPA, National Enforcement Investigations Center,
Denver, CO.
1978 (revised 1983). NEIC policies and procedures. EPA-330/9-78-001-R. U.S.
EPA, National Enforcement Investigations Center, Denver, CO.
U.S. EPA- 1980a. Interim guidelines and specifications for preparing quality
assurance project plans. QAMS-005/80. U.S. EPA, Office of Monitoring Systems
and Quality Assurance, Washington, DC. 18 pp.
U.S. EPA. 1980b, Samplers and sampling procedures for hazardous waste streams.
EPA-600/2-80-018. U.S. EPA, Municipal Environmental Research Laboratory,
Cincinnati, OH.
U.S. EPA. 1981. Manual of groundwater quality sampling procedures.
EPA-600/2-81-160. Robert S. Kerr Environmental Research Laboratory, Ada, OK.
105 pp.
15-162
-------
U.S. EPA. 1982. Test methods for evaluating solid waste. SW-846. U.S. EPA,
Office of Solid Waste and Emergency Response, Washington, DC.
U.S. EPA. 1985a. Contract laboratory program statement of work. Inorganic
analysis, multi-media, multi-concentration. SOW No. 785. July, 1985. U.S. EPA,
Environmental Monitoring Support Laboratory, Las Vegas, NV.
U.S. EPA. 1985b. Laboratory data validation. Functional guidelines for evaluating
inorganic analysis. October, 1985. U.S. EPA, Office of Emergency and Remedial
Response, Washington, DC.
15-163
-------
CASE STUDY 27: CORRECTIVE ACTION AND THE IMPLEMENTATION OF
INTERIM MEASURES •
Points Illustrated
o Interim corrective measures may be necessary to protect human health
or the environment.
o The evaluation of the need for definitive corrective measures.
Introduction
The development and implementation of a comprehensive corrective action
plan can be a time-consuming process. Between the time of the identification of a
contaminant release and the completion of corrective actions, existing conditions
or contaminant migration can endanger human health or the environment. Under
these conditions interim measures are required. The case study presented below
illustrates the implementation of interim measures to reduce contaminant
migration and to remove the imminent threat to the nearby population from
exposure to contaminants in drinking water, and also illustrates the decision-
making process as to whether definitive corrective measures may be necessary.
Facility Description
The facility in this case study is an underground tank farm located at a
pharmaceutical manufacturing plant. The tank farm encompasses an area
approximately 140 feet by 260 feet and contains 30 tanks ranging in size from
12,000 to 20,000 gallons. The tanks are used to store both wastes and raw
materials for the various batch manufacturing processes performed at the plant.
Typical wastes include carbon tetrachloride, acetonitrile and chloroform. At the
time of the release, the tank farm had no cap to prevent the infiltration of rainfall
or runoff. It also did not nave jerms to provide containment /or surface apiiis. No
leak detection or leachate collection systems were present.
15-164
-------
Geological and Hydrological Setting
The site is underlain by silty soil overlying limestone. The weathered
limestone beneath the site is very permeable (up to 210 ft/day) due to the solution
of rock along joints and bedding planes in the limestone. Depth to the limestone
varies from 3 to 80 feet beneath the tanks and from 15 to 190 feet downgradient of
the site.
The ground water system beneath the site consists of two aquifers. The
upper one, an unconfirmed limestone aquifer', is located about 300 feet below the
surface. The deep aquifer is an artesian aquifer in another limestone formation
located about 1200 feet below the land surface. Ground-water flow in the upper
aquifer is controlled by both the regional flow system and local channelized flow
through solution conduits. The upper aquifer discharges to a canal 3 miles north of
the site. Figure 15-50 shows the ground water elevation contours in the vicinity of
the site. Regional average ground water flow velocity was estimated at 4 ft/day,
but ground water velocities on the order of 50 ft/day have been measured in some
channelized areas. Channelized flow is also responsible for local deviations in flow
direction.
Release Characterization
A contaminant release from the tank farm was discovered when one of the
tanks used for waste storage was found to be empty. The waste stored in the tank
was predominately carbon tetrachloride (CC14) (a carcinogen with a risk specific
dose (RSD) of 0.001 ug/1), with some acetonitrile (a systemic toxicant for which no
health criteria presently exists) and chloroform (a systemic toxicant for which the
reference dose (RfD) is 0.4 mg/1). Approximately 15,000 gallons of waste liquids
had been routed to the tank before the leak was discovered. Excavation of the
tank revealed ruptures in at least three locations. Initial ground-water monitoring
after the tank rupture was discovered identified CC14 in a well located 2500 feet
downgradient of the site, at concentrations above the Risk Specific Dose for CC14
of 0.001 ug/1.
15-165
-------
•MW22, .
X24.X3.4
• MW20
3.13
KEY
4.0— Eltvation aOOv#
Mtan S«a ltv«i
I Groundwattr
Flow Lmes
Groundwater
Monitoring W«ll
(•nd El«v in Ft )
Contour* baMd on Wttcr L*v*a
t«k«n on 5/2/84
(Contour mttrvai 0 2 Ft )
9319
1003
Figure 15-50.
Ground water level elevations and
upper limestone aquifer.
flow directions In
15-166
-------
Contaminants from the leaking tank were found to have dispersed laterally
within a two foot thick sand bed which underlies the tanks. The contaminated area
was approximately 5600 ft2. High levels of CC14 were found throughout the sand
layer. Concentrations of CC14 in the. natural soil ranged between undetected and
2200 rag/1, Observed concentrations were well above the RSD for CCl^.
Concentrations generally decreased with depth due to adsorption onto the clay
particles in the soil. Carbon terachloride apparently moved downward with little
lateral dispersion until reaching the soil-limestone interface. Upon reaching the
unsaturated limestone, the contaminants then appeared to have rapidly dispersed
over an area of about 12 acres before entering the aquifer.
Interim Corrective Measures
Immediate action to contain the release in the aquifer was taken. This
involved pumping the well where CC14 had been found continuously at its full
capacity of 450 gpm.
All drinking water in the vicinity of the release was obtained from wells
installed in either the shallow or artesian aquifers. Immediately after the
detection of the release, all domestic and industrial wells located north of the
facility were tested for CC14 contamination. Test results showed contamination of
several shallow water supply wells. Based on this information and the inferred
ground water flow direction to the north-northeast, wells serving two small
communities and a nearby motel were closed. The facility operator hired all
trailable water tanks available and supplied water for immediate needs until a
temporary water supply could be implemented. Water from an unaffected artesian
well was then used to supply water to these communities.
The design and operation of the tank farm was altered in an attempt to avoid
similar problems in the future. A fiber-reinforced concrete cap was installed over
the tank farm to prevent the infiltration of rainfall and runoff, thus minimizing
further contaminant migration In the soil. The ruptures wers repaired, md a tank
monitoring system was also developed and implemented at the site.
15-167
-------
Definitive Corrective Measures; Saturated and Unsaturated Zones
A comparison of CC14 concentrations within the ground water to the RSO for
CC14 (O.OOlug/1) indicated that definitive corrective measures may be necessary.
Due to the high mobility of CC14 within the unsaturated zone, and the potential for
continued inter-media transfer from this zone to the ground water, definitive
corrective measures for both the saturated (ground water) and unsaturated zones
should be evaluated in a corrective measures study (CMS).
Case Discussion
The development and implementation of corrective action at a site may take
a substantial length of time. Depending on the nature of the release and the site
involved, interim measures, such as alternative water supplies, were required to
minimize the effects on human health and the environment. Comparison of
constituent concentrations with health and environmental criteria indicated that
definitive corrective measures may be necessary and that a corrective measures
study (CMS) should be initiated.
-------
CASE STUDY 28: METHODOLOGY FOR CONSTRUCTION OF VERTICAL FLOW NETS
Point Illustrated
• Construction of a vertical ground-water flow net can be a valuable tool
for evaluating ground-water (and contaminant) pathways and for
determining additional actions that may be necessary to accurately
delineate.the ground-water flow regime at a facility.
Introduction
Constructing a vertical flow net at a facility provides a systematic process for
analyzing the accuracy of ground-water elevation and flow data, and can therefore
foster a better understanding of the ground-water flow regime at the site.
Facility Description and History
The site contains a large chemical manufacturing facility of approximatley 300
acres located beside a major river in the northeastern United States. The site has
been used for chemical manufacturing by different companies since 1904 and has a
long historyof on-site waste management. Several solid waste management units
have been identified at the facility. This is the same facility as discussed in Case
Studies 3,4,18, and 20.
Geologic and Hydrologic Setting: At depths of 150 to 200 feet the site is
underlain by bedrock identified as arkosic sandstone. Above this bedrock are glacial
deposits consisting of a thick bed of hard till, overlain by lacustrine sediments and
deltaic and outwash deposits. Discontinuous lenses of till were identified within the
deltaic deposits. A trough cut into the thick-bedded and trending approximately
southeast to northwest has been identified. See Figure 1.
-------
«
a
-------
The river beside the facility flows westward and discharges into the main stem
of a larger river approximately 4 miles west of the facility. A small tributary (Brook)
borders the facility to the southwest and west. Swamp-like areas are present near
the tributary, it is suspected that the arkosic sandstone outcrops in the river
adjacent to the facility. Whether this visible rock is a large glacial erratic or an
outcrop of the arkosic sandstone bedrock is an issue identified during previous
investigations and may be important in characterizing the ground-water flow
regime at the facility.
Program Design
The site was investigated in two phases. Phase I (1981-1984) included the
installation and monitoring of wells MW-1 through MW-12, while Phase II (1984-
1985) consisted of 34 soil borings, installation of wells NW-13 through MW-57, and
monitoring and sampling of all wells. This two-phased approach allowed for the
use of the initial monitoring well data and soil boring data to determine the
placement of the Phase II monitoring wells. Further discussion of this two-phased
approach is provided in Case Studies 4 and 19.
Data Analysis
Evaluation of the data was conducted based on information provided by the
owner/operator, including the water-level elevation data presented in Table 1.
Well locations and water-level elevations in the wells were mapped and compared
to elevations of the midpoint of the well screens, to show relative hydraulic head
differences from well to well. Vertical gradients are a reflection of different head
values at different elevations. For each well, the head can be determined at the
elevation of the midpoint of the well screen by measuring the water-level elevation
in the well. Different head values corresponding to different screen elevations are
used to evaluate vertical gradients. During the plotting of this map, anomalous
data were identified and marked for further investigation.
The geology of the site and the depositional processes forming the aquifer
were studied to determine what sorts of hydrogeologic phenomena might be
expected. Glacial outwash deposits exhibit trends in sediment size and sorting.
Sediment size
-------
Table 1
Ground-Water Elevation Summary Table Phase
i
Well
Number
MW-1
MW-2
MW-3
MW-4
MW-5
MW-6
MW-7
MW-8
MW-9
MW-10
MW-11
MW-1 2
MW-1 3
MW-1 4
MW-1 5
MW-1 6
MW-1 7
MW-1 8
MW-1 9
MW-20 .
MW-21
MW-22
MW-23
MW-24
MW-25
MW-26
MW-27*
MW-28
MW-29
MW-30
!.VIW-31
MW-32
MW-33
Ground
Elevation
(ft.)
162.80
162.50
174.20
201.90
186.30
144.30
144.60
155.10
160.50
160.40
154.70
159.50
162.20
162.10
162.00
162.00
162.00
161.90
137.10
137.20
141.40
141.60
204.30
143.90
143.80
143.80
142.70
142.80
172.00
172.20
203.10
174.20
Well
Depth
(ft.)
76.50
22.50
31.00
54.00
47.50
39.50
19.50
24.00
61.00
30.00
27.00
26.50
29.00
29.00
29.00
29.00
71.00
72.00
24.00
17.00
26.50
15.10
225.50
70.00
39.00
24.00
46.00
23.00
85.50
24.85
61.00
94.00
Midpoint of
Well Screen
Elevation '
145.7
150.4
141.3
107.3
" 127.6
133.6
135.0
132.9
130.2
135.5
139.2
139.1
139.1
135.5
104.5
103.4
116.6
123.7
118.4
13.0
-10.2
76.4
107.3
123.2
100.2
123.3
90.0
150.3
145.6
83.7
Screen
Length
(ft)
3
3
3
3
3
3
3
3
3
3
3
3
10
10
10
3
25
25
5
5
5
5
20
5
5
5
5
5
5
5
5
5
Water
Level Elevation
9/1/82
150.54
156.85
149.95
135.78
135.94
149.04
141.53
144.62
140.57
141.05
141.22
140.66
140.67
140.87
140.52
140.53
127.83
127.82
135.39
135.35
184.98
136.47
130.20
130.17.
127.86
127.88
152.70
ISI.oS
154.78
150.49
* Not installed.
1Assume screens are installed one foot above the bottom of the well.
-------
Table 1 (continued)
Well
Number
MW-34
MW-35
MW-36
MW-37
MW-38
MW-39
MW-40
MW-41
MW-42
MW-43
MW-44
MW-45
MW-46
MW-47
MW-48
MW-49
MW-50
MW-51
MW-52
MW-53
MW-54
MW-55'
MW-56
MW-57
Steam
Reference
Points
SRP-1
SRP-2
SRP-3
SRP-4
SRP-5
SRP-6
SRP-7
SRP-8
Ground
Elevation
(ft.)
186.20
203.20
189.40
189.50
189.30
154.90
173.80
173.70
134.20
139.50
139.50
144.32
144.15
141.50
141.60
143.00
143.00
157.00
157.00
159.30
145.80
145.90
133.60
141.90
Well
Depth
(ft.)
75.80
106.25
101.20
48.00
135.30
68.00
47.50
75.30
64.00
32.10
28.00
35.00
25.00
34.00
17.00
72.20
30.20
70.30
34.00
77.90
52.00
35.00
20.30
Midpoint of
Well Screen
elevation'
113.9
100.4
91.7
145.0
57.5
90.5
129.8
101.9
73.7
80.9
115.0
112.8
122.6
111.0
128.1
74.3
116.3
90.2
126.5
84.9
97.3
114.4
116.8
Screen
Length
(ft)
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5
5.
5
5
5
114.41
114.92
116.05
115.86
NA
123.31
137.28
134.11
Water
Level Elevation
9/1/82
149.72
144.31
143.22
150.51
145.04
142.45
146.59
141.95
117.62
117.24
119.62
128.97
126.48
131.91
131.74
123.22
123.85
149.58
139.48
141.09
120.18
121.63
119.84
•Not installed.
1Assume screens are installed one foot above the bottom of the well.
-------
decreases and sorting increases trending from the marginal to the distal portions of
the deltaic/lacustrine deposits. 1 It is expected that this tendency will be reflected in
hydraulic conductivities throughout the outwash deposits at the facility. There is
some suggestion of such a trend in the head data from the site.
The map of head values and screen midpoint elevations were evaluated
considering both the possible hydrogeologic phenomena expected for the geology
of the area and the depositional processes creating the aquifer. Several working
hypotheses were developed to explain the apparent ground-water flow patterns
and the identified vertical gradients.
• Hypothesis 1: Vertical gradients can be explained by classifying areas
where the vertical gradients were reflective of discharge and recharge
areas. See Figure 2.
• Hypothesis 2: The top surface of the till forms a trough with a saddle.
See Figure 1. The vertical gradients showing higher head with depth
reflect the movement of water as it flows upward over the saddle.
• Hypothesis3: The vertical gradient may correlate with locations of
buildings and parking lots at the site. Recharge occurs primarily where
the ground is not paved. The downward gradient near the river may be
caused by runoff flowing downhill and recharging the ground water at
the edge of the pavement.
• Hypothesis 4: Most of the ground-water flow is horizontal. The vertical
gradients reflect phenomena whose scale is smaller than the resolution.
of available data, and an accurate interpretation cannot be made.
Geologic systems exhibit heterogeneity on different scales, causing
fluctuations in head on different scales. The small-scale fluctuations
detected at the site are due to undefined causes and may represent:
1. detaiis of stratigraphy (such as til! beds in parts of ;he cutwash
deposit),
2. artificial recharge and discharge (such as leaky sewer pipes), or
3. errors in the data.
'Mary P Anderson, "Geologic Facies Models: What Can They Tell Us About Heterogeneity," presented to the American
Geophysical Union, Baltimore. May 18,1987
-------
o.
*
0)
o
(8
e
V
B
O
hi
0)
CM
oo
«H
U4
-------
To characterize flow at the site and to support the design of corrective
measures (if needed), a working (conceptual) model of flow at the site should be
developed. This model, in this case a vertical flow net, can be used to identify data
gaps and to prioritize gathering of the necessary additional information.
Considering the hypotheses developed, an area for characterizing the vertical flow
regime was selected. Determination of this area, where a geologic cross section and
flow net will be constructed, was based on:
• Assumptions and requirements necessary to construct flow nets, as
identified in the Criteria for Identifying Areas of Vulnerable
Hydroqeolqov. Appendix B: Ground-Water Flow Net/Flow Line
Construction and Analysis (Vulnerable Hydrogeology, Appendix B). For
example, ground-water flow should be roughly parallel to the direction
of the cross-section and vertical flow net.
• Flow being representative of the hydrogeology of the facility.
• Flow representing the major paths of ground-water movement. For
example, the aquifer is shaped like a trough and a major portion of the
ground-water flow occurs in the middle of this trough; therefore, a cross-
section and flow net should be constructed along the axis of the trough.
A geologic cross-section was constructed for the area of interest and is
identified as T-T' in Figure 1. A flow net was then constructed following the
methodology described in Vulnerable Hydroqeology. Appendix B; see Figure 3.
Construction of a vertical flow net requires a graphical solution of Darcy's Law.
Data that do not fit the solution become evident in Figure 3 as shown, for example,
by the head value for MW 52.
Construction of a vertical flow net allowed for a systematic evaluation of the
various hypotheses. Hypothesis 1, where vertical gradients are labled recharge and
discharge, is rejected because the magnitude of the graidents varies by two orders
of magnitude in a very irregular pattern (compare well clusters MW 14-18 and MW
12 and 53); there is no apparent reason that natural recharge would vary so
irregularly. Hypothesis 2 seemed reasonable initially, but after closer inspection, is
rejected because upward gradients are not consistently found near the saddle.
8
-------
g
.-H
bu
00
-------
Hypothesis 3. is feasible and deserves further study. Aerial photographs were
examined to identify paved and unpaved areas, but the available ground-water
data are insufficient for detailed correlation to these distinct areas. Additional data
are needed to construct a more-detailed flow net to further evaluate this
hypothesis. Hypothesis 4, which asserts that most of the flow is horizontal,
addresses the area of the site where the major portion of ground-water flow occurs.
Although it relies on undefined causes to explain fluctuations, it reflects the most
logical explanation of the data.
Results
During construction of the flow net and testing of the hypotheses several
issues were identified. One of the most important gaps in the study to date is how
localized flow at the site fits into the regional ground-water flow regime. Regional
flow issues would need to be resolved prior to determining the extent and type of
corrective measures, if necessary. The following regional flow issues were
identified:
• Geologic information beyond the facility property boundary is necessary
to explain the suspected bedrock in the middle of the River directly
beside the site to characterize the regional ground-water flow (i.e., to
determine the possibility for contamination of regional ground water).
The difference in elevation of the top of the bedrock in the River and the
top of the bedrock throughout the facility is approximately 120 feet.
How can this be explained? Is the bedrock surface irregular or is this rock
a glacially-transported boulder exposed in the river? How does this
affect regional ground-water flow?
•
• Data consistently show a downward gradient (i.e., recharge conditions)
near the river. This is difficult to explain because rivers in this region are
not expectd to be losing streams (Heath, 1984). The exoected flow
direction near a ground-water discharge area, in this case a gaining
stream, is upward. Data points showing downward flow near the river
are not included in flow net T-T'. (Further investigation of vertical
gradients near the River is recommended). If this downward gradient
near the river is confirmed, near-water-table contamination could move
10
-------
downward and contaminate'deeper ground-water. If deeper, regional
contamination must be addressed, and corrective measures may be
significantly more difficult and extensive.
Other issues deal with localized flow patterns that may affect design of corrective
measures. Resolution of these issues will probably not change the overall scope of
corrective measures, but would need to be considered in the detailed design.
These localized flow pattern issues are as follows:
• The hydraulic head in the Brook is higher than the head in the closest
wells in the aquifer, but the water slopes toward the stream. This is
inconsistent. If ground water from the site is not discharging into this
stream, fewer interceptor wells may be needed.
• Anisotropy must be taken into account in determing the region of flow
captured by interceptor wells, drains, etc.
• Till identified as lenses in outwash deposits may actually be continuous
with upgradient till, causing the aquifer to flow under confined
conditions. Are the till beds isolated lenses or are they continuous? If the
till- beds in the outwash aquifer are continuous and isolate adjacent
zones within the aquifer, they will have the potential of blocking flow to
interceptor wells that may be included in the corrective measures plan.
• Vertical gradients of 0.25 and 0.002 in the same geologic unit are
presented. Are these gradients accurate and how can they be explained?
There could be artificial discharge (pumping) or recharge (possibly from a
leaking sewer) near the wells showing a high vertical gradient. The areas
labeled discharge areas show no signs of surface water or other surficial
evidence of discharge. Artificial recharge and discharge may create areas
of relatively constant head, such as where ground water contacts leaky
sewers; these areas could limit the growth of cones of influence of any
interceptor wells or drains. Also, any contaminated water that may be
discharging from pipes should be identified and corrected.
11
-------
Case Discussion
Further investigation is necessary to resolve the above issues. Regional flow
issues should be resolved first. This information would be used to better
understand localized flow patterns which would affect the design of corrective
measures. The following options for further investigation are suggested:
1. Study the regional geology and hydrogeology. Techniques that could be
employed by using existing data include review of geologic maps,
analysis of well logs, and interpretation of existing surface geophysical
data (e.g., gravity and magnetic surveys). Measurement of water level
elevations in wells outside the site would also be useful.
2. Conduct a detailed study of the depositional environment of the glacial
deposits on the site. This should provide a better understanding of flow
patterns.
3. Collect a full-year series of head data at existing wells to differentiate
transient from steady-state (e.g., artificial from natural) effects in the
measured heads.
4. Conduct multiple-well pumping tests to determine the degree of
connectivity of geologic formations using wells at different depths and
locations. [Note: This should be done with careful attention to details of
well construction so that it is understood exactly what is being
measured.]
5. Collect detailed chemical data (including major ions and contaminants)
at the existing wells and interpret them to aid in characterizing the flow
regime.
6. Drill one or more wells into the bedrock near the river to determine the
vertical component of ground-water flow at this location.
Options 1 through 5 above are recommended prior to drilling additional wells
in the outwash deposits, unless more wells are needed to delineate the release.
12
-------
Further single-well hydraulic conductivity tests in the glacial deposits are not
recommended at this time. The large-scale flow in the outwash aquifer should be
determined by the location and relative degree of continuity of the till versus the
sand because the permeability contrasts between the till and sand.is so much
greater than the variability among the different sands. (See paper by Graham Fogg
in Water Resources Research, 22, 679.) Single-well tests would be useful for
determing localized hydraulic conductivities of the sand bodies, not their
connectivity.
Gathering existing data and constructing an initial vertical flow net proved
useful in identifying data gaps in defining ground-water flow, and identified
problems due to differing interpretations of the existing data. Determining options
for gathering additional data necessary to resolve these issues was based on a
qualitative understanding of the ground-water flow regime gleaned form
construction of the vertical flow net.
References
Fogg, Graham. Water Resources Research 22, 679.
Heath. 1984. Ground Water Regions of the U.S. USGS Water Supply Paper No. 2242
^
U.S. EPA. 1986. Criteria for Identifying Areas of Vulnerable Hydroqeoloqy.
Appendix B: Ground-Water Flow Net/Flow Line Construction and Analysis. Office
of Solid Waste. Washington, D.C. 20460.
13
-------
CASE STUDY 29: USE OF DISPERSION ZONE CONCEPTS IN THE DESIGN OF A
SURFACE WATER MONITORING PROGRAM
Point Illustrated
• Estimation of the dispersion zone of contaminants downstream of a
release point can be used to help design a surface water monitoring
program.
•
Introduction
When a contaminant is initially released to a body of water, the concentration
of the contaminant will vary spatially until fully dispersed. In streams, the
contaminant will disperse with the surrounding ambient water as the water moves
downstream and will eventially become fully dispersed within the stream.
Downstream from this point, the contaminant concentration will remain constant
throughout the stream cross-section, assuming that streamflow is constant and that
the contaminant is conservative (e.g., nondegradable). The area in which a
contaminant's concentration will vary until fully dispersed, referred to here as the
dispersion zone, should be considered when determining the number and location
of sampling stations downstream from the release point.
Facility Description
A facility that processed zinc, copper and precious metals from ores operated
along a stream for five years. The plant was closed after being cited for repeated
fish kills, reportedly due to failures of a tailings pond dike. At present, the site is
covered with tailings containing high concentrations of copper, zinc, cadmium,
arsenic, and lead. There is no longer a tailings pond. This is the same facility
described in Case Study Number 10.
Site Setting
The site is located on coarse colluvium (hill-slope deposits of weathered
bedrock) and fine-grained alluvium. These deposits are typically 50-feet thick.
-------
Metamorphic rock (phyllite) underlies the unconsolidated materials. Ground water
moves laterally in the gravel formations from the steep valley walls toward the
stream.
The site is located about 400 feet from the stream. Two drainage ditches cross
the lower portion of the site and merge prior to leaving the site. The ditch carries
the combined flow and discharges directly into the stream (Figure 1). No other
tributaries enter the stream within 2 miles of this location. Downstream from the
release point, stream width and depth remain fairly constant at 45 and 3 feet,
respectively. Mean stream velocity is 0.5 feet per second and channel slope is .0005
feet per foot.
Sampling Program
A surface water monitoring program was designed as part of a Phase I
investigation to determine the extent of contamination in the stream. Existing data
from previous sampling had shown high concentrations of metals in the drainage
ditch sediments (e.g., 5,170 mg/kg Cu and 11,500 mg/kg Zn). Ground-water data
from the plant's well showed measurable concentrations of Cu (7 ug/0 and Zn (54
ug/i). The ground-water concentrations were only slightly above the Water Quality
Criteria for aquatic life (5.6 vg/t for Cu and 47 ug/i for Zn, U.S. EPA, 1976). These
differences are.within the limits of analytical error. The contribution of metals to'
the stream by ground-water discharge was considered to be negligible.
Based on a review of the plant history and the available water quality and
sediment data, a monitoring program was designed. The potential pathways by
which metals could reach the stream appeared to be direct discharge from the
drainage ditch, discharge of contaminated ground water, and storm water runoff
over the general facility area. Plant records indicated that typical flows in the
drainage ditch at its confluence with the stream varied from 1 to 3 cubic feet per
second (cfs) in the Spring. During extreme flood conditions, the flow in the ditch
exceeded 20 cfs. In the Summer, flows in the drainage ditches at ail locations were
-------
I
190 tort
Figure 1. Sampling Station Locations for Surface Water Monitoring
* . Located approximately 1030 feet downstream of the confluence of the ditch
with the stream.
-------
less than 0.5 cfs. Resuspension of contaminated sediments in the ditches during
storm runoff appeared to be the most likely pathway for metals to reach the
stream. The specific metals of concern were identified as As, Cd, Cu, Pb and Zn,
based on the processes used at the plant and the composition of the ores which
contained some arsenopyrites (with As, Cu), galena (Pb), and sphalerite (with Zn,
Cd).
The available soil and water quality data from previous sampling were
reviewed to help determine the likely fate of the metals. The pH of soils in the area
is about 6.5 and they contain about 0.5 percent organic matter by weight. Under
such conditions, the metals, particularly Pb, would be expected to adsorb onto the
soil particles. In the on-site tailings piles, the pH of core samples ranged between
3.3 and 4.9. Low soil pH values had been measured in sediments in the drainage
ditch just downgradient of the tailings pile. The pH of the stream during the
previous sampling was 6.9. The suspended solids concentration was 10 mg/l.
Estimates of the distribution of metals between the dissolved and adsorbed
phases for a range of partition coefficients (K) are shown in Table 1. For example, if
Kp = 104 and the suspended solids concentration was 10 mg/l, 90 percent (0.9) of
the metal present would be in the dissolved phase. This information indicated that
even though a metal (e.g., lead) was known to strongly sorb, a significant amount
could still be transported in the dissolved phase. Thus, both water and suspended
solids should be analyzed for metals. The complete list of parameters selected for
measurement in the Phase I investigation and the rationale for their selection are
outlined in Table 2.
The sampling stations were selected to determine stream water quality up and
downstream of the site and to determine whether particulates with sorbed metals
were deposited on the stream banks or streambed. The sampling stations and the
rationale for their selection are listed in Table 3. The station locations are shown in
Figure 1. Because floods were considered to be one cause of contamination
incidents, samples were to be collected under both high and low flow conditions.
The location of the downstream station (S8) was determined after estimating
the stream length that may be required for complete dispersion of the
contaminants. The following equation was used for this estimation:
-------
Table 1
Relationship of Dissolved and Sorbed Phase Contaminant Concentrations
to Partition Coefficient and Sediment Concentration
Kp SS Cw/CTa
10o 1
10
100
1000
10000
101 1
10
100
1000
10000
102 1
10
100
1000
10000
103 1
10
100
1000
10000
104 1
10
100
1000
10000
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
1.0
0.9
1.0
1.0
1.0
0.9
0.5
1.0
1.0
0.9
0.5
0.1
1.0
0.9
0.5
0.1
0.0
After Mills etaL, 1985.
•The fraction dissolved (Cw/C-r) is calculated as follows:
Cw 1
CT 1+KpX 5x10-6
where ,
-------
Table 2
Parameters Selected for Surface Water Monitoring Program
Parameters
Rationale
Metals- As, Cd,Cu,Pb,Zn
pH
Dissolved Oxygen, Sulfide, Fe(ll),
Fe(lll)
Alkalinity
Total Dissolved Solids
Major Cations (Ca * 2, Mg* 2, Na*,K*,
NH4*)and
Major Anions (CI-, SC>4-2
Suspended Solids
Streamflow
Determine extent of contamination
Needed to predict sorption behavior,
metal solubility, and speciation
Needed to determine redox conditions
which influence behavior of metals,
particularly the leaching of tailings
A measure of how well buffered a water
is, allows consideration of the likelihood
ofpH change
Used as a water quality indicator and for
QA/QC checks
May identify other waste sources, can
influence fate of trace metals
Needed to predict the fraction of metal
in water which is sorbed
Needed to compute mass balances and
assist in identifying sources of observed
contamination
-------
Table 3
Selected Surface Water Monitoring Stations and Selection Rationale
Station
Media
Rationale
Drainage ditch west of
site(S1)
Drainage ditches on site
(S2 and S3)
Downstream of
confluence of 2 ditches
(54)
Mouth of drainage
ditch (S5)
Stream (S6, S7 and S9)
Stream (S8)
Water and sediments
Determine whether off-site
drainage is significant source of
contamination
Water and sediments Identify on-site sources
Water and sediments
Water, suspended
sediment, bedload
Water, suspended
sediment, bedload
Water, suspended
sediment, bedload
Provide information for
checking mass balances from the
2 drainage ditches
Determine quality of direct
discharge to stream
Determine upstream water
quality
Determine quality downstream
of site following complete
dispersion and provide data for
mass balance
-------
DZ a 0.4 wlu
0.6d /gds
where:
DZ = dispersion zone length, ft
w a width of the water body, ft
u a stream velocity, ft/sec
d a stream depth, ft
s a slope (gradient) of stream channel, ft/ft
g = acceleration due to gravity (32 ft/sec 2).
Using the above equation, the estimated stream length required for complete
contaminant dispersion is 1030 feet. This can serve as an approximate distance
downstream from the release point at which a sampling station should be located.
Case Discussion
This case illustrates the use of contaminant dispersion zones in the design of a
surface water monitoring program. In this example, the data indicate that
approximately 1030 feet of flow within the described stream channel is required
before a contaminant will become fully dispersed. A downstream station should
therefore be located at or below this dispersion zone to fully characterize the
extent of the release. An adequate number of sampling stations should also be
located upstream from this point.
8
-------
CASE STUDY 30: EXAMPLE HEALTH AND SAFETY PLAN
The following health and safety plan was taken directly from the following
EPA document.
U.S. EPA. 1983. Personnel Protection and safety. Office of Emergency and
Remedial Response. Washington, D.C. 20460.
-------
APPFMDIX IV
SITE SAFETY PLAN
I. INTRODUCTION
A site safety plan must be prepared (or reviewed) by a qualified safety
person for each response Involving hazardous substances. As soon as
possible after operations at an incident commence, safety requirements
must be written, conspicuously posted, distributed to all response
personnel and discussed with them. In non-emergency situations, for
example, remedial action at abandoned hazardous waste sites, safety plans
can be developed simultaneously with general operation plans and
implemented when remedial actions begin. Emergency situations may require
verbal safety instructions and use of standard operating safety procedures
until specific safety protocols can be written. For any incident, the plan
must include health and safety considerations for all activities required
at the incident. The safety plan must be periodically reviewed to keep it
current and technically correct.
II. MINIMUM REQUIREMENTS
As a minimum, the site safety plan must:
Evaluate the risks associated with the incident and with each operation
conducted.
Identify key personnel and alternates responsible for both site safety
and'response operations.
Address Levels of Protection to be worn by personnel during various
site operations.
Designate work areas (exclusion zone, "contamination reduction zone, and
support zone), boundaries, size of zones, distance between zones, and
access control points into each zone.
Establish decontamination procedures for personnel and equipment.
Determine the number of personnel and equipment needed 1n the work
zones during Initial entries and/or subsequent operations.
Establish site emergency procedures, for examole, escape routes,
signals for evacuating work parties, emergency communications (Internal
and external), procedures for fire and/or explosions, etc.
Determine location and make arrangements with the nearest medical
facility (and medical life squad unit) for emergency medical care for
routine-type injuries and toxicological problems.
IV-1
-------
I. and
Train personnel for any non-routine site activities.
may affect the health and
to the
IY-2
-------
PERSONNEL SAFETY PLAN
OTTATI AND GOSS
HAZARDOUS WASTE SITE
Kingston, New Hampshire
Third Revision
Revised: 19 May 1982
This is a copy of an actual safety plan currently
being used on the Ottatl and Goss hazardous waste
site. It 1s provided here only as an example of
how a safety plan may be assembled. Some of the
original contents have been omitted because they
can be found elsewhere in the manual.
IV-3
-------
CONTENTS
TOPIC . ' PAGE
Purpose 1
Applicability 1
Responsibilities
1. On-Seen* Coordinator 1
2. Safety Officer 2
Site Organization 2
Topographic Map (Figure 1) 3
Zones of Contamination 4
Site Plan (Figure 2) 6
Level of Hazard Determination 8
Minimum Equipment and Respiratory Protection 9
Air Monitoring Survey 10
Emergency Contingency Plan 11
Emergency Telephone Numbers 13
Emergency Route Map "Kingston* (Figure 3) 14
Emergency Route Map "Exeter" (Figure 1) 15
Emergency Route Map "Haverhill" (Figure 5) 16
Degrees of Hazard and Personnel Protection Levels (Attach. 1) 17
Appendices
Decontamination
Local Contingency Plan
Safety Equipment (Exposure Action Levels)
Chemical Resistance Charts
Index of Skin Toxic Chemicals (OHM-TADS)
Index of Skin Absorbed Chemicals (OHM-TADS)
Dermal Toxicity Rating 6 Recommended Levels of Protection
D.O.T. Hazardoud Classification Chart
Chemical Characteristics Category List
Windchill Chart
Heat Stress Casualty Prevention Plan
• I
II
III (omitted)
IV (omitted)
V (omitted)
71 (omitted)
VII (omitted)
VIII (omitted)
IX
X
XI
IY-4
-------
I Purpose
The purpose of this plan is to assign responsibilities, establish personnel
protection standards, mandatory operating procedures, and provide for con-
tingencies that aay arise while operations are being conducted at the
Ottati and Goss Hazardous Vaste Site in Kingston, New Hampshire.
II. Applicability
The provisions of the plan are mandatory for all EPA personnel and personnel
under contract to EPA while Section 311 activities are being conducted
at the site. These activities include investigation, sampling, and mitigati
undertaken on the site or at any off-site areas which may be affected by
contamination from the site. All visitors to the aite will be required
to abide by these procedures. It is strongly recommended that State of
New Haapshire personnel involved in cooperative site operations implement
these procedures.
III. Responsibilities
1. On-Scene Coordinator (OSC)
j
In accordance with UO CFR 1510.36: "The OSC shall direct Federal polluti
control efforts and coordinate all other Federal efforts at the scene
of a discharge or potential discharge."
A. At the Ottati * Goss site, the OSC has the primary responsibility
for:
1. Assuring that appropriate personnel protective equipment is
available and properly utilized by all SPA and contractor
personnel.
2. Assuring that personnel are aware of the provisions of this
plan, are instructed in the work practices necessary to ensure
safety, and in planned procedures for dealing with emergencies.
IV-5
-------
3. Assuring that personnel are aware of the' potential hazards
associated with alte operations.
4. -^upervlsing the monitoring of safety performance by all per-
sonnel to ensure that required work practices are employed.
5. Correcting any work practices or conditions that may result
la Injury to personnel or exposure to hazardous substances.
B. The On-Scene Coordinator for this site Is: Robert Ankstltus.
2. Safety Officer
In accordance with the draft chapter 9 of EPA's Occupational Health
and Safety Manual, as ordered by Executire Order 12196: "The Safety
Officer is responsible for implementing the safety plan at the site."
A. At the Ottatl 4 Coss site, the Safety Officer shall:
1. Conduct site monitoring of personnel hazards to determine the
degree of hazard present.
2. Determine personnel protection levels and necessary clothing
and equipment to ensure the safety of personnel.
*j
3. Evaluate weather and chemical hazard information* and recommend
to the OSC any necessary modifications to work plans and per*
sonnel protection levels to maintain personnel safety.
4. Men!tor the safety performance of all personnel to ensure that
the) required practices are employed.
B. The Safety Officer for this alte la: Gordon Bollard
Site Organization
The Ottatl 4 Coss Hazardous Waste Site is located In Kingston, Rev Hampshire.,
near Rte. 125 (See Map, Figure 1). The site Is part of a borrow pit operati,
1V-6
-------
Ott«tl
HAVCXHIU. OUAMANOLX
H*w Htmft
it mmm
(It* of Op«(»tian*
-------
adjacent to a small stream which flows via a marsh into Country Pond.
Within 100 yards of the streaa 1300 drums, in various stages of deteril
ation were abandoned. These open and sealed drums contain various hazardoi
substances. Some of these drums, due to their condition and displacement
by rainfall, have contaminated the ground in the area where they were
abandoned.
During the winter and spring and 1981* EPA undertook operations to move
the drums into staging areas preparatory to sampling them. During the >
course of these operations an H-NU was used to obtain organic vapor levels
for the site. The ambient air (Including background) for the site usually
indicated less than 5 ppa organic vapor with frequent Increases to 20-30
ppm in the immediate vicinity of the drum movement operations. Some in-
dividual drums, checked on a random basis, indicated 20004- ppm (within
6 Inches of the bung).
In order to reduce the potential for contaminant migration and reduce the
risk of personnel exposure to hazardous substances, three zones will be
established. The three zones are: 1) Exclusion Zone; 2) Contamination!
Reduction Zone; and 3) The Clean Zone.
V. Determination of Zones of Contamination
*
A. Exclusion Zone (See Site Plan, Figure 2)
•j
The Exclusion Zone is the area southerly of the small streaa at point
"H*. This area encompasses the sand and gravel pit. Within this zone
the designated "level of hazard* will be established, necessitating
the use of personnel protection equipment.
Dut to tht condition of the drums and the soil and debris of the former
drua storage site, a potential for wind migration of contaminants
exists. The Exclusion Zone has, therefore, been made sufficiently
large to encompass /orseeable dispersion based on operations conducted
during the spring of 1981. In order to facilitate operations In this
zone, three sub-areas will be established:
*• "*rea C« will be the area within the Exclusion Zone where only W
background vapor levels exist. This area serves as a buffer within
IV-8
-------
which wind dispersion of contaninants might occur. In "Area C"
personnel will be required to wear the protective clothing desig-
nated for "Area B" operations and carry an air purifying respirator.
A red flag will be flown in a prominent location to serve as a
wind reference.
2. "Area B" is the area within which the wearing of both protective
clothing and respiratory protection will be required due to the
potential for contamination from the drums during work activities.
This area is in fact four locations: 1) Staging Area 1; 2) Staging
Area 2; 3) Staging Area 3; and *0 Staging Area 1 (including the
former drum handling area.
NOTE: Experience during the summer of 1981 indicates that outside
the above areas the level of hazard is negligible, but when oper-
ations resume it may be necessary to form them into one area.
3. "Area A" is the tern used to delineate "hot spots" within "Area
B". A hot spot is a point at which the contaminant levels are,
at least periodically, higher than the level of hazard indicated
for "Area B" and require an increase in protection above that
provided. These spots will be identified by an orange "bicycle
pennant." Personnel working in these areas will wear the res-
piratory protection and safety clothing necessary for the special
degree of hazard. Additionally, personnel will use any necessary
monitoring devices and safety tools to complete their specific
tasks in a safe Banner.
In order to provide an adequate Safety Zone the special level of
hazard protection area will extend at least 50 feet from the pennant.
B, Contamination Reduction Zona
The Contamination Reduction Zone serves as a buffer between the Clean
Zone and the Exclusion Zone. The zone incorporates the entire borrow
pit area and a portion north of the small streaa.
IY-9
-------
fifur* 2
IV-10
-------
Personnel intending to enter the Exclusion Area shall don the appro-
priate protective clothing for the area(s) that they intend to enter,
•3 well aa, obtain the respiratory protective equipment that is necessary
prior to crossing the Hotline at point "H" Into the Exclusion Area.
Decontamination and Exclusion Zone equipment storage and maintenance
will be carried out in this Zone. No equipment used in the Exclusion
Zone will enter the Clean Zone until it has been decontaminated in
the Contamination Reduction Zone. To support Exclusion Zone activities
three facilities will be situated in the zone.
1. Decontamination Station
The Decontamination Station will be located at the other perimeter
of the Contamination Reduction Zone. All personnel who have been
within the Exclusion Area shall pass through a decontamination
procedure prior to re-entering the Clean Zone (See Decontamination
Procedure, Appendix I).
2. Heavy Equipment Park
A Heavy Equipment Park will be designated near the Decontamination
Station for the storage, maintenance, and decontamination of vehicles
used in the Exclusion Zone.
t
3. Weather Shelter
A Weather Shelter will be located in the Contamination Reduction
Zone to provide some protection to personnel when taking breaks,
without requiring them to fully decontaminate.
C. Clean Zone
The Clean Zone la the outer area and may be considered clear of con-
tamination. The past history of the site, however, indicataa that
parts of this zone were used to stockpile drums prior to their being
processed through a drum recycling facility owned by the Great Lake
Container Corporation. Ground contamination is therefore present.
Work that might be necessary in the former storage areas is to be
considered to require protective clothing.
IV-11
-------
Depending on the location, rtapi.'atc,.--- protection r^-y net be ne:es3.
Private vehicles not needed for operations are restricted to the
lot at the Command Post.
The EPA Command Post, or Mobile Laboratory, an-i an Equipment Trailer
will be located within the Clean Zone.
1. The Comsand Post will serve as the CSC's hraJquarters and will
be equipped with:
a) First aid supplies
b) Weather Station
c) Communications
d) Safety Plans
e) Communication Vatch
2. The Mobile Laboratory will be equipped to analyze and categorize
the materials at the site. Access will be restricted in order
to minimize contamination and interference with analysis.
3. The Equipment Trailer will be used to store safety materials
to their distribution from the clean side of the Decontamination
Station. Other equipment will be stocked here for future use and
equip.isnt will be repaired here after decontamination.
~1 -*--"inat: c n_ cf _ the Level of Hazard
The level of hazard will be determined by periodic monitoring of the site
for combination by the Safety Officer (See Attachment 1).
The investigation, to date, has not indicated the presence of substances
which cay be absorbed through the skin. The investigation indicates that
various substances, primarily industrial solvents, are present in suffi-
cient quantities to cause irritation to the eyes, lungs, intestinal tract,
and many are known or suspect carcinogens. Only a small portion of the
druas hava been sampled; therefore, personnel will be required to wear
as a minimum:
A. Cloves
A 2-glove system will be worn.
IV-12
-------
1. Inner Gloves - Nitrile or PVC
2. Outer Gloves - Butyl Rubber or Nitrile
The inner glovea will be worn at all times within the Exclusion Zone.
The outer gloves will be work when contact with drums and other con-
taminated materials is expected.
B. Disposable Splash Suit
All personnel, as a minimum, within the Exclusion Zor.r- will wear a
polylaminated Tyvek disposable coverall.
C. Head Gear
Hard hats will be worn at the site if overhead work occurs.
D. Eye Protection
Face shields or goggles will be worn within the Exclusion Zone. "Safety"
glasses are not sufficient protection and contact lenses will not be
worn at the site.
E. Boots
Cover boots will be worn in the Exclusion Area. Steel-toed boots will
be worn by personnel handling drums, or coverboots over steel-toed
workshoes.
w»
F. Respiratory Protection
The respiratory protective devices used at this site will fall into
three categories:
1. Positive Pressure, Demand, Open Circuit, Self Contained Breathing
Apparatus (SCBA or Positive Pressure Demand Airline Respirator)
2. Air Purifying Respirator
3* Constant Flow
Only NIOSH/MSHA approved equipment will be used.
The level of respiratory protection to be used will be based upon the
use of a photoionization detector (HKU). In order to provide a maximum
of protection, the following procedure will be followed:
IV-13
-------
1. Positive pressure, demand, open circuit, SCBA will be worn if tfc,
level of organic vapors exceeds 25 ppm.
2. An aic. purifying respirator will be used when the organic vapor
-level la between 6 ppm and 25 ppa.
3. If the organic vapor level is 5 ppo or less, no device is necessary,
but either an air purifying respirator or approved escape device
will be carried.
Examples of NIOSH/MSHA approved devices are:
1. SCBA - MSA HOI Pressure Deaand TC 13F-30
2. Air Purifying - MSA Ultra Twin Cartridge TC 21C-188 (cartridges
and/or cannisters oust be NIOSH approved for the respirator.)
3' Escape - Robertshaw 5-minute TC 13F-28
•PPM in Breathing Zone Wear
0-5 Nona
6-25 Air Purifying
26+ S.C.B.A.
CAUTION: Individual jobs at the site may require personnel to
wear an increased level of protection than generally necessary
for the site. For example: 1) acid raingear; 2) butyl rubber
aprons; 3) SCBA when others on air purifying respirator; and U)
hard hats with faceshielda.
Note: Operations vill be conducted during the summer months when
excessive ambient air temperatures may cause personal injury and
increased accident probability. Safety procedures to avoid heat
stress casualty potential are outlined in Appendix XI.
•H-NU calibrated to 9.8 with benzene.
VII. Air Monitoring Survey
The Safety Officer will survey the site every second hour, and at such
other times as deemed necessary by an alteration of wind speed or directi<
or the type of work being conducted, using a photoionizatlon detector.
IV-14
-------
The Safety Officer shall use a copy of the Site Plan to indicate the lo-
cation where readings were recorded, velocity of the wind, and the KNU
reading. A minimum of 10 locations will be checked during each bihourly
survey.
Three activated charcoal filter pumps will be maintained in the Contami-
nation Reduction Zone and sampled twice a day in order to assess the coo-
position of the organic vapors upwind, downwind, and within the Exclusion
Zone.
VIII. Emergency Contingency Plan
On-site emergencies can be expected to result from fire, chemical reaction
of drum contents or personnel casualty. If an incident occurs necessita-
ting a response to an emergency, the OSC will sound an air horn. The
signal is at least 5 short blasts (each of 1 second duration).
Personnel will assemble at the Decontamination Station to receive SCBA,
orders to evacuate, or other assignments.
If the weather deteriorates to the point where the OSC believes work should
cease, he will sound 1 prolonged blast (1 of 4-6 second duration) to order
the crew to cease operations and assemble at the Decontamination Station.
Fire *
o
If a fire emergency occurs the crew will assemble at the Decontamination
Station, on the 5 blast signal. The OSC will issue his response orders,
having already alerted the Fire Department (642-5512) and the Police Depart-
ment (772-4716) to execute the Town Emergency Plan (See Appendix II).
Fire fighting materials on-site will include:
1. 20 gallons of A Triple F foaa,
2. 2 large dry chemical extinguishers (mounted on wheels)
3* 5 20-lb. dry chemical extinguishers
*. 4 MSA 401 SCBAs (for F.D. use only - additional to all others).
IV-15
-------
Drua Leak
^
Personnel will assemble at the Decontamination Station, on the 5 blaat
signal. The QSC will issue his cleanup orders, in order that the problem
may be controlled and cleaned up rapidly. In addition to materials on-
site for the job, the following materials will be on-site:
Line - 200 Ib.
Speedy Dry - 200 Ib.
'Overpack Drums - 100
Lab Packs - 25
Reconditioned Hazmat Drums - 100
Personnel Casualty
Personnel will assemble at the Decontamination Station, on the 5 blast
signal, except for one man who will remain with the casualty. The OSC
will issue orders for first aid assistance to the casualty. If the casualty
has sustained an injury which may Involve contact with contaminated material,
a sample of the material will be taken for immediate analysis.
Severe Casualties
The OSC will contact the Kingston Ambulance (542*5512) for assistance. ,
If the casualty requires transfer to a hospital, the primary hospital will
be the Exeter Hospital. The OSC will contact the hospital (778-7311) and
inform them of the incident and the nature of the injury. If Exeter Hospital
is unable to assist (due to other emergencies), the OSC will contact Hale
Hospital in Haverhill (372-7141) and alert them.
IV-16
-------
EMERGENCE TELEPHONE NUMBERS
Immediate Emergencies
1. Kingston Police Dept. (603) 772-4716
2. Kingston fire Dept. (603) 642-5512
3. Kingston Aabulanoe (603) 612-5512
State your naae, location, and the nature of the emergency.
Emergency Support
1. U.S. EP1 (617) 223-7265
2. Petbody Clean Industry (617) 567-6500
3. Exeter Hospital (603) 778-7311 (7 digits only)
Directions:
A. North on Xte. 125 to Xte. Ill
B. East on Xte. Ill to Exeter Town Rail
C. Turn right
0. Follow Xte. 108 to hospital entrance on Highland St. (See Maps,
Figures 3 A 4).
i
4. Hale,Hospital, Haverhill, MA (617) 372-7141 (7 digits only)
Directions:
A. South on Xte. 125 to Raverbill*s Central Plaza
B. Turn left onto Ginty Bird. (Xte. 97)
C. Following Xte. 97 to Rale Hospital's entrance on Voodbrldge
Road (See Haps, Figures 3 A 5).
State Official*
1. State Fire Marshall*a Office (603) 271-3336
2. NHVSPCC (603) 271-3503
3. Bureau of Solid Waste Mgat. (603) 271-4611
IY-17
-------
fl««*r4«u> gita. Slt«
•••pthtra'
map of
ROCKIKGHAM COUNTY
-------
-------
-------
Decree of
Hazard
DEGRZES OF HAZARD
AND
LEVELS OF PERSONNEL PROTECTION
Conditions
Level of Protection
First Degree
1. Unknown Hazards
"2. IDLH Atmospheres
3. Oxygen Deficient
Atmospheres
1. Unknown Hazards
2. Percutaneous Chemicals
3. Vapors which can injure
the skin
Self Contained Breathing
Apparatus (SCBA) of the
Positive Pressure Demand Ty
Appropriate Type of Fully
Encapsulating Suit.
Second Degree
1. ZDLH Atmospheres
2. Oxygen Deficient
Atmospheres
1. Liquids which can injure
the skin
Self Contained Breathing
Apparatus (SCBA) of the
Positive Pressure Demand Tyj
Boots, Gloves, Rain/Chemical
Splash Suit with Rood.
Third Degree
Atmospheres with at least 1.
19HI Oxygen
Atmospheres for which the
Chemical & Concentration
are Known and are below
IDLH level.
Contaminants have Good
Warning Properties
Atmospheres for which
a NIOSH/MSHA approved
Cartridge/Cannister is
available
2.
1.
Approved Air Purifying
Respirator (Gas Mask) with t
Appropriate Approved Cartrie
(Cannister)
Carry: Approved Emergency
Escape Unit
Boots, Gloves, ChemClos (Spl
Suit if necessary). Face Shi
or goggles.
Fourth Degree
1. Atmospheres with at least 1,
19«j% oxygen
2. No IDLH Atmospheres
3. Dust and other
particulates in the Air 2,
1. No Harmful Chemicals or
Atmospheres that night 1,
injure the skin
Approved Air Purifying
Respirator (Gas Mask) with t
Appropriate Approved Cartrid
(Cannister).
Carry: Approved Emergency
Escape Unit
Boots, Gloves, Coveralls,
Face Shield/Goggles
Fifth Degree
Atmosphere with at least
19*jl Oxygen
Atmosphere which
contains no Hazards-But
where a Hazardous
Substance Incident
'ight occur.
Carry: Approved Emergency
Escape Unit
Appropriate Clothing for the
investigation/inspection.
IV-21
Attachment
-------
APPENDIX I
Decontamination Procedure
The Decontamination Procedure shall be used when contact with contaminants
is »ade or when personnel depart the Standby Zone.
1. Personnel Scrub Boots at the Pans provided Outside the DECONSTA.
Z. Disposable Tyvek Clothing and Gloves are Disposed of into the
the Dirty Trash Drum provided outside the DECONSTA.
t
3. Spent Cartridges/Cannisters are disposed of into the Drum provided
outside the DECONSTA.
4. The DECONSTA is entered for the Decontamination of other equipment
in the pans provided in the DECONSTA.
5. Use a new set of inner gloves to clean equipment.
6. Dispose of any generated Dirty Trash in the Drua provided in the
Contamination portion of the trailer.
7. Depart the DECONSTA via the Clean Roan, for the issue of new
clothing/material, or depart from the Standby Zone.
-------
s
eduction Zone
Contamination
41
^J
to «
• to
|2
0 •
• •••
e •%•
e
•'
•
•
•
?
to
2
«
to
£
5
^
r i
to
2
a
0|
0!
t
O
-1
to •«
•^ to
0 f*
•
•a
ca
S
*4
U
0
11
b
l\
Cotami nation Bide
0
to
2
a
1
to
2
to
to
44
6
c ** 1
\SJ
ftfl ]
0
ri\
1 * /
[w /
> JC
* *
to •
** to
O H
0
P)
vlx
•
* w
tl
«4
«> to
e **
S.S
(0 U
IV-23
-------
CASE STUDY 31: USE OF HISTORICAL AERIAL PHOTOGRAPHS AND FACILITY MAPS
TO IDENTIFY OLD WASTE DISPOSAL AREAS AND GROUND-
WATER FLOW PATHS.
Points Illustrated
• Aerial photographs taken over many years in the life of a facility can be
used to locate old solid waste management units (SWMUs).
• Historical aerial photographs can be used to identify
geologic/topographic features that may affect ground-water flow paths.
Introduction
In gathering information pertaining to investigation of a release, historical
aerial photographs and facility maps can be examined and compared to current
aerial photographs and facility maps. Aerial photographs can be viewed as stereo
pairs or individually. Stereo viewing, however, enhances the interpretation because
vertical as well as horizontal spatial relationships can be observed. The vertical
perspective aids in distinguishing various shapes, tones, textures, and colors within
the study area.
^
Aerial photographs and facility maps can be used for the following:
• Providing evidence of possible buried drums. Historical photographs can
show drums disposed of in certain areas where later photographs show
no indications of such drums, but may show that the ground has been
covered with fill material.
• Showing previous areal extent of landfill or waste management area.
Earlier photos might show a much larger waste management area than
later photographs.
• Showing areas that were dry but now are wet, or vice versa, indicating a
possible release from an old waste management area.
-------
• Showing changes in land use patterns (e.g., a landfill in an early
photograph could now be a park or be covered by buildings).
• Soil discoloration, vegetation damage, or enhanced vegetative growth
can sometimes be detected, indicating possible contaminant migration.
• Geologic/hydrologic information, such as faults, fracture or joint systems,
old stream courses (channels), and the contact between moraines and
outwash plains.
Facility description
This facility is the same as previously described in Case Studies 3,4,18 and 20.
Data collection and analysis
Over the past 50 years aerial photographs were taken of the facility area.
Interpretation of the photographs produced important information that is shown
diagramatically in Figure 1. Solid Waste Disposal Area 2 (SWDA-2) was lower in
elevation in 1940 than it is now. In fact, the area appears to have been leveled and
is now covered by vegetation, making it difficult to identify as a SWMU at ground
level. Another area was identified as a possible waste disposal area from a historical
review of photos. Further study of photos, facility maps and facility files revealed
this to be a former Liquid Waste Disposal Area (LWDA), designated as LWDA-2 on
Figure 1.
The use of these historical photographs also revealed geologic features that
could affect the ground-water flow system under the facility. In this case,
monitoring well data indicated a general northwesterly ground-water flow
direction, in addition to a complex flow pattern near LWDA-1 and SWDA-1 (Figure
1). Recent photographs were analyzed, but because of construction and other
nearby activities (e.g., cut and fill, sand and gravel mining), conclusions could not be
-------
o
4-> S-
-------
drawn. A review and analysis of old photographs revealed the existence of a buried
stream channel of the river (Figure 1). This buried stream channel was identified as
a preferential path for ground water and consequently contaminant migration.
Additional monitoring data and further analysis of subsurface geologic data is
needed to determine the full impact of the buried stream channel on the ground-
water flow regime.
Case Discussion
Analysis and interpretation of a series of historical aerial photographs and
facility maps spanning a period of over 50 years enabled facility investigators to
identify the following:
(1) Location of waste disposal areas (e.g., old SWMUs);
(2) Changes in topography (related to earlier disposal activities); and
(3) Possible preferential pathways (e.g., old stream channel) for migration of
ground water and contaminants.
This information was used to identify areas for more detailed sampling and
analysis.
Analysis of historical facility maps and historical aerial photographic
interpretation can be a very powerful tool in a RCRA Facility Investigation, but
should be used in combination with other investigative techniques to result in a
thorough characterization of the nature, extent, and rate of contaminant
migration.
------- |