1 . i
United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EP AlRODIR08-93/075
September 1993

iPB94~964407
&EPA
Superfund
Record of Decision:
Montana Pole and
Treating, MT
u . ~. Environmental Protection Agene,
Reglo~ III Hazardous Waste ~ .
Techmcallnformation Center
84) Ches~nut Street ,9th Floor
Hazardous Waste Collection
Information Resource Center
US EPA Region 3
Philadelphia I P A 19107
lEl?A RepG]rt (G@~~~~~n(iJ!lJ1)
lirei«DrmaJiul!DlIi\ 1R!~$@Mi'(i:~ ~~IIi\~IID~
~$ lE~~ OO@~n@~ 3
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50272.101
p
 REPORTDOCUMENTA~ON T 1. REPORT NO. 2.     3. Reclplent'a Acc88810n No. 
   PAGE   EPA/ROD/R08-93/075           
4. Title and Subtitle                5. Report Data   
 SUPERFUND RECORD OF DECISION            09/21/93 
 Montana Pole and Treating, MT           6.    
 First Remedial Action - Final               
7. Author(a)                8. Performing Organization Rapt. No.
II. Performing Orgenizatlon Heme and Add....            10 Project Ta8k/Work Unit No. 
                     11. Contract(C) or Grant(G) No. 
                     (C)    
                     (G)    
12. Sponsoring Organization Heme and AcId.....            13. Type of Report . Period eovarad
 U.S. Environmental Protection Agency           
 401 M Street, S.W.               800/800   
 Washington, D.C. 20460            14.    
15. Supplemantary Note.                    
      PB94-964407               
16. Abstract (Umlt: 200 worela)                   
 The Montana Pole & Treating site is a former wood treating facility located in Butte,
 Montana. Land use in the area is predominantly industrial, with some commercial and
 residential areas adjacent to the site. The site borders Silver Bow Creek, a former
 smelter site, and the Butte/Silver Bow Creek Superfund site, and lies within the 
 lOO-year floodplain of Silver Bow Creek. Residents near the site use one ground water
 well for domestic purposes and lawn watering. From 1946 to 1984, onsite wood treating
 operations utilized a five percent PCP solution mixed with petroleum carrier oil to
 preserve the timber, except for a brief period in 1969 when creosote was used as a wood
 preservative. This solution was applied to wood products in butt vats and pressure
 cylinders (retorts), and the retorts were used to dry timber by the Boulton-process,
 which produced a residual two-phase oil and water condensate. The water phase 
 reportedly was discharged into an onsite, unlined drainage ditch, which flowed toward
 Silver Bow Creek. In addition, onsite sedimentation ponds in the wastewater discharge
 ditch area apparently were used for the disposal of waste generated by the wood 
 treatment process. In 1969, an onsite fire destroyed several of the plant areas, which
 were later rebuilt. But as a result of this fire, an onsite spillage of the 
 (See Attached Page)                  
17. Document AnaIy8ia a. Descriptors                
 Record of Decision - Montana Pole and Treating, MT        
 First Remedial Action - Final               
 Contaminated Media: soil, sediment, debris, sludge, gw, sw     
 Key Contaminants: organics (dioxin, oils, PAHs, phenols), metals (arsenic, chromium,
        lead)                
 b. IdentlfieralOpen-Ended Terms                 
 c. COSATI FleldfGrQlP                   
18. Availability Stat_nt          19. Security CIaaa (This Aaport) 21. No.ofPagea 
                   None   188 
  ,             20. Security CIaa (This Paga) 22. PrIce 
                   None     
(SM ANSl-Z39.18)
SM In8trucll- on ,,-,,-
OPTIONAL FOAM 272 (4-77)
(Formerty NTIS-35)
Department of Commerce

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EPA/ROD/R08-93/075
Montana Pole and Treating, MT
First Remedial Action - Final
Abstract (Continued)
PCP/petroleum product occurred. Additional seepage of the product resulted from broken
pipes and valves damaged by the fire. In 1980, a closed-loop process water system was
constructed to eliminate overland discharges of Boultonizing water. In 1983, a citizen
complaint concerning oil seeping into Silver Bow Creek prompted a State investigation that
verified an oil seep and detected oil-saturated soil onsite and adjacent to the creek. In
1985, an EPA and State investigation confirmed the presence of PCP, PAHs, and
dioxins/furans in onsite soil and oil samples. Subsequently, in 1985, EPA initiated a
removal action which included excavation and onsite temporary storage of approximately
10,000 yd3 of contaminated soil; dismantling and temporarily storing onsite tanks,
retorts, pipes, and other hardware; installation of two ground water interception/oil
recovery systems to alleviate oil seepage into the creek; and fencing. In 1992, EPA
initiated a second removal action to control and recover floating LNAPLs from the ground
water. This process included the installation of an 890-foot sheet piling and ten
recovery wells, each one containing two pumps: one to collect free-floating oil and pump
it to an onsite storage tank and the other to pump contaminated ground water to an onsite
granular activated carbon treatment facility. In 1993, the water treatment facility began
operations and the system installed in 1985 was shut down. . This ROD provides a final
remedy for onsite contamination of the hot spot areas, former plant process area, the
drainage ditch running to Silver Bow Creek, wastewater discharge ditch area, and the LNAPL
plume. The primary contaminants of concern affecting the soil, sediment, debris, sludge,
ground water, and surface water are organics, including dioxin, oils, PAHs, and phenols;
and metals, including arsenic, chromium, and lead.
The selected remedial action for this site includes excavating approximately 208,000 yd3
of contaminated soil to a depth of two to four feet from the surface soil hot spots, the
former process area, the wastewater discharge ditch, and soil areas near the ground water
table ~hat are impacted by LNAPLs; treating onsite the excavated soil and approximately
10,000 yd3 of contaminated soil, stored onsite since the "1985 removal action, using
above-ground bioremediation; treating approximately 44,000 yd3 of inaccessible
contaminated soil by extracting LNAPLs, followed by soil flushing and in-situ
bioremediation; backfilling the excavated areas with the treated soil, installing soil
covers, and regrading and revegetating the area; incinerating offsite approximately 26,500
gallons of contaminated sludge, LNAPLs, and oil, with offsite disposal of residuals;
decontaminating approximately 9,100 yd3 of debris and equipment onsite, with offsite
disposal in a RCRA landfill; containing contaminated ground water and LNAPLs using
physical and/or hydraulic barriers to prevent the spread of contamination and to limit
releases of contamination to Silver Bow Creek; treating contaminated ground water onsite
using oil/water separation and granular activated carbon, and bioremediation or UV
oxidation, if necessary, followed by onsite discharge of the treated water to surface
water or reinjection into the aquifer; treating inaccessible ground water by in-situ
bioremediation; allowing surface water to naturally attenuate; addressing contaminated
stream sediment through natural biodegradation; monitoring ground water; and implementing
institutional controls, including deed and ground water use restrictions. The estimated
present worth cost for this remedial action ranges from $27,530,000 to $55,200,000, which
includes an estimated annual O&M cost ranging from $657,000 to $4,420,000.
PERFORMANCE STANDARDS OR GOALS:
Chemical-specific soil, sediment, sludge, and debris cleanup goals are based on a health
risk of 10-6, and include benzo(a)anthracene 4,200 ug/kg; benzo(a)pyrene 4,200 ug/kg;
benzo(b)fluoranthene 4,200 ug/kg; dioxins/furans 0.2 ug/kg; indeno(1,2,3-cd)pyrene 4,200
ug/kg; and PCP 34,000 ug/kg. Chemical-specific ground water cleanup goals are based on
SDWA MCLGs and MCLs or risk-based levels, and include acenaphthene 360 ug/l; anthracene
360 ug/l; benzo(a)anthracene 1 ug/l; benzo(b)fluoranthene 0.2 ug/l; benzo(g,h,i)perylene 1
ug/l; benzo(k)fluoranthene 1 ug/l; benzo(a)pyrene 0.2 ug/l; 2-chlorophenol 45 ug/l;
chrysene 1 ug/l; dibenzo(a,h)anthracene 0.2 ug/l; 2,4-dichlorophenol 27 ug/l;

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EPA/ROD/R08-93/075
Montana Pole and Treating, MT
First Remedial Action - Final
Abstract (Continued)
dioxins/furans 3xlO-S; flouranthene 360 ug/l; fluorene 360 ug/l; indeno(1,2,3-cd)pyrene 1
ug/l; PCP 1 ug/l; phenanthrene 360 ug/l; pyrene 360 ug/l; 2,3,5,6-tetrachlorophenol 267
ug/l; and 2,4,6-trichlorophenol 6.5 ug/l. Chemical-specific surface water cleanup goals
are based on SDWA MCLGs and MCLs and State standards, and include benzo(a)anthracene 1
ug/l; benzo(a)pyrene 0.2 ug/l; benzo(b)fluoranthene 0.2 ug/l; chrysene 1 ug/l;
dibenzo(a,h)anthracene 0.2 ug/l; PCP 1 ug/l; and pyrene 360 ug/l.
(

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'III. -..
RECORD OF DECISION
.(
MONTANA POLE AND TREATING PLANT
NATIONAL PRIORITIES LIST SITE
BUTTE, MONTANA
-,
Montana Department of Health & Environmental Sciences
Solid & Hazardous Waste Bureau
Cogswell Building
Helena, Montana 59620
(Lead Agency)
(Support Agency)
United States
Environmental Pr()tection Agency
Region VITI - Montana Office
Federal Building, 301 S. ?ark, Drawer 10096
Helena, MT 59626-0096
September 1993
6" .
II
4

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RECORD OF DECISION
MONTA~~A POLE AND TREATING PLAlYf NATIONAL PRIORITIES LIST SITE
-'
INTRODUCTION
The Montana Department of Health & Environmental Sciences and the Environmental
Protection Agency (EP A) present the Record of Decision for the Montana Pole and Treating
PIQJ1t site (the Site). The Record of Decision is based on the Administrative Record,
Remedial Investigation/Feasibility Study, the Proppsed Plan, the public comments received,
including those from the potentially responsible parnes, EPA comments, and other new
information. The Record of Decision presents a brief outline of the Remedial
Investigation/Feasibility Study, actual and potential risks to human health and the
environment, and the selected remedy. The state followed EPA guidance' in preparation of
the Record of Decision. The Record of Decision has the following three purposes:
1.
Certify that the remedy selection process was carried out in accordance with the
requirements of the Comprehensive Environmental, Response, Compensation and
Liability Act (CERCLA), 42 U.S.C. 9601 er seq., as amended by the Superfund
Amendments and Reauthorization Act (SARA), and, to the extent practicable, the
National Contingency Plan (NCP);
--:.
2.
Outline the engineering componentS and remediation goals of the selected remedy;
and
3.
Provide the public with a consolidated source of information about the history,
characteristics, and risks posed by the conditions at the Site, as well as a summary of
the cleanup alternatives considered, their evaluatIon, and the rationale behind the
selected remedy.
The Record of Decision is organized into three distinct sections:
o
The Declaration functions as an abstract for the key infonnation contained in
the Record of Decision and is the section of the Record of Decision signed by
the Director of the Montana Department of Health and Environmental Sciences
and the EP A Regional Administrator,
o
The Decision Summary provides an overview of the site characteristics, the
alternatives evaluated, and the analysis of those options. The Decision
Sumnlary also identifies the selected remedy and explains how the remedy
. 'Guidance on Preparing Superfund Decision Documc:nts: The Proposed Plan. the Record of Decision.
Explanation of Differences. the Record of Decision Amendment. Interim Final. EPAl540/G. July 1989.

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-"
'.. --
fulfills starurory requirements: and
o
The Responsiveness Summary addresses public commems received on the
Proposed Plan. the Remedial Investigation/Feasibility Study and ather
infonnation in the administrative record.
2

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-'
TABLE OF CONTE.'ITS
P3.ge
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
,. ill
UST OF TABLES
. . IV
UST OF FIGURES. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
ACRONYMS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . v
1.
II.
m.
IV.
..,
v.
SITE NAME, LOCATION Al'ID DESCRIPTION. . . . . ',' . . . . . . . .
SITE IllSTORY ................................... 1
Enforcement Actions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., 2
IllG:m..IGHTS OF corvIMUNITY PARTICIPATION. . . . . . . . . . . . .
-+
SCOPE AND ROLE OF RESPONSE ACTION. . . . . . . . . . . . . . . . .
6
7
7
8
SUMMARY OF SITE CHARACTERISTICS. . . . . . . . . . . . . . . . . .
Principle Contaminants of concern. . . . . . . . . . . . . . . . . . . . . . . . .
Summary of Narure and Extent of Contamination. . '. . . . . . . . . . . . . .
Major Sources of Contamination from Historical 'MPTP
Operations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Conceptual Model of Contaminant Fate and Transport. . . . . . . . . . . ., 11
Estimated Volumes of Contaminated Materials. . . . . . . . . . . . . . . . . 11
VI.
SUMMARY OF SITE RISKS. . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Human Health Risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Cont;tmin;tnts of Concern for Human Health. . . . . . . . . . . . . . 15
Exposure Assessment. . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Toxicity Assessment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
Risk Characterization. . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Ecological Risks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
Cont~min3nts of Concern. . . . . . . . . . . . . . . . . . . . . . . . . . 19
Potential Receptors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
EcolOgical Toxicity Assessment. . . . . . . . . . . . . . . . . . . . . . 20
Ecological Risk Characterization. . . . . . . . . . . . . . . . . . . . . . 20
VII.
DESCRIPTION OF AL~"J'ATIVES ...................... 22
vm. SUM!vlARY OF COMPARATIVF ANALYSIS OF ALTERNATIVES.. 32
Evaluation and Comparison Criteria. . . . . . . . . . . . . . . . . . . . . . . . 32
Overnll protection of public health and the environment. . . . . . . 33

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-'
IX.
'.
x.
XI.
xn.
TABLE OF CONTENTS (Cant.)
Page
Compliance with applicable or relevant and appropriate
requirements (ARARs) . . . . . . . . . . . . . . . . . . . . . . . 33
Long-term effectiveness and permanence. . . . . . . . . . . . . . . . . 33
Reduction of toxicity, mobility and volume. . . . . . . . . . . . . . . 34
Sholt-term effectiveness. . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Implementability ............................... 35

Cost. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

State agency acceptance. . . . . . . . . . . . . . . . . .. . . . . . . . . 36
Community acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . 36
SELECTED R.El\ffiDY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Components of Selected Remedy. . . . . . . . . . . . . . . . . . . . . . . . . . 38
Estimated Costs of the Remedy. . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Cleanup Levels. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
PointS of Compliance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Perfonnance Standards for Soils. . . . . . . . . . . . . . . . . . . . . . . . . . 43
Perfonnance Standards for Groundwater. . . . . . . . . . . . . . . . . . . . . 44
Compliance Sampling Program . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Engineering and Institutional Controls. . . . . . . . . . . . . . . . . . . . . . . 46
Contingency Measures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47
STATUTORY DEI'ERMINATIONS ....................... 49
Protection of Human Health and the Environment. . . . . . . . . . . . . . . 50
Compliance with Applicable or Relewnt and Appropriate Requirements.. 51
Cost-Effectiveness. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 53
Utilization of Permanent Solutions and Alternative Treatment
Technologies (or Resource kovery Technologies) to the
Maximum Extent Practicable. . . . . . . . . . . . . . . . . . . . . . . . 54
Preference for Treatment as a Principal Element. . . . . . . . . . . . . . . . 54
DOCUMENTATION OF SIGNIHCANT CHANGES. . . . . . . . . . . . . 55
R£FERElIlCES . . . . . . . . . . . . - . . . . . . . . . . . . . . . . . . . . . . . . 56
APPENDIX A - Applicable or Relevant and Appropriate RequirementS
APPENDIX B - Administrative Record Index
-'
~4';:
, '
, ..
11

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 Table 1
 Table 2
 Table 3
 Table ~
 Table 5
 Table 6
 Table 7
 Table 8
 Table 9
 Table 10
 Table 11
 Table 12
-> Table 13
 Table 14
 Table 15
 Table 16
 Table 17
 Table 18
 Table 19
 Table 20
 Table 21
 Table 22
 Table 23
 Table 24
 Table 25
 Table 26
 Table 27
 Table 28
 Table 29
4 -.
LIST OF TABLES
Contaminated Soil Volume Estimates
Preliminary Remedial Action Goals for Soils
Contaminants of Concern for Human Health
Potential Exposure Pathways Under Current Land Use Conditions
Potential Exposure Pathways Under Furore Land Use Conditions
Exposure Assumptions for Dennal Contact with Soil for Workers and
Trespassers
Exposure Assumptions for Incidental Ingestion of Soil for Workers and
Trespassers
Exposure Assumptions for Incidental Ingestion of Surface Water
Exposure Assumptions for Direct Contact with Sediments
Exposure Assumptions for Dennal Contact with Soil for Residents
Exposure Assumptions for Incidental Ingestion of Soil for Residents
Exposure Assumptions for Ingestion of Home Grown Vegetables (Compounds
other than Pentachlorophenol)
Exposure Assumptions for Ingestion of Home Grown Vegetables Grown in
Soil Containing Pentachlorophenol
Exposure Assumptions for Ingestion of Groundwater
Exposure Point Concentrations for Surficial Soils
Exposure Point Concentrations for Groundwater
Exposure Point Concentrations for Surface Water and Sediments
Summary of Estimated Risks for Future On-Site Residents
Summary of Estimated Risks for Future On-site Workers
Summary of Estimated Risks for Current On-Site Trespassers
Estimated Cost for Remedial Alternative 5B
Estimated Cost for Soil Flushing SyStem
Soil Cleanup Levels
Pathway Risk Estimates Corresponding to Soil Cleanup Levels
Groundwater Cleanup Levels
Surface Water Cleanup Levels
Discharge to Surface Water Cleanup Levels
Toxicity Equivalence Factors for PARs
Toxicity Equivalence Factors Dioxins and Furans
ill

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.-.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Fibure 7
Figure 8
Figure 9
Figure 10
Figure 11
Figure 12
Figure 13
Figure 14
Figure 15
Figure 16
Figure 17
LIST OF FIGl"RES
Butte. Montana Area Map
Iv1PTP Site Layout and Features
PCP and TPH Concentrations in Surface Soils
PCP Concentrations in Subsurfac ~ Soils
Subsurface Soil Boring Cross Sections
PCP Concentrations in Subsurface Soil Boring Cross Section A-A'
PCP Concentrations in Subsurface Soil Boring Cross Section B-B'
PCP Concentrations in Subsurface Soil Boring Cross Section C-C'
Surface Water, Groundwater and LNAFL Contamination
PCP Concentrations in Groundwater (site area)
PCP Concentrations in Groundwater (downstream area)
Estimated Lateral Extent of PCP Plume (site area)
Estimated Extent of LNAPL Plume
PCP, PAH and TPH Concentrations in Surface Water
PCP, PAH and TPH Concentrations in Creek Sediments
Site Conceptual Model
Estimated Lateral Extent of Surface and Subsurface Soil Contamination
IV

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ARAR
ARCO
AWQC
BRA
CERCLA
,~
DNAPL
EPA
ERA
FS
GAC
In
LAO
LNAPL
MCL
MCLG
MDHES
IvIPTP
NCP
OSWER
PAISI
PAH
PCDD
PCDF
PCP
PRAG
PRP
RA
RCRA
RD
RID
RI
ROD
SARA
TCDD
TEF
TPH
UV
VOC
ACRo~r\ylS
Applicable or Relevant and Appropriate Requiremems
Atlantic Richfield Company
Ambient Water Quality Criteria
Baseline Risk Assessment
Comprehensive Environmental Response, Compensation, and Liability Act of
1980
Dense Non-Aqueous Phase Liquid
u. S. Environmental Protection Agency
Ecological Risk Assessment
Feasibility Study
Granulated Activated Carbon
Hazard Index
Lower Area One
Light Non-Aqueous Phase Liquid
Maximum Contaminant Level
Maximum Contaminant Level Goal
Montana Department of Health and Environmental Sciences
Montana Pole and Treating Plant
National Contingency Plan
Office of Solid Waste and Emergency Response
Preliminary Assessment/Site Inspection
polynuclear Aromatic Hydrocarbon
Polychlorinated dibenzo-p-dioxins
Polychlorinated dibenzofurans
Pentachlorophenol
Preliminary Remedial Action Goal
Potentially Responsible Party
Remedial Action
Resource Conservation and Recovery Act
Remedial Design
Reference Dose
Remedial Investigation
Record of Decision
Superfund Amendments and Reauthorization Act
Tecrachlorodibenzo(p ) dioxin
Toxicity Equivalence Factor
Total Petroleum Hydrocarbons
Ultraviolet (light)
V olawe Organic Carnon
v

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DECISION SUlVIl\tIARY

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~10NT..\...'L\ POLE ROD - DECLARATIO~
SITE NA.l'-fE A.ND LOCATION
Montana Pole and Treating Plant Site
Bune, Montana
STATEMENT OF BASIS A..J.'ID PlJRPOSE
This decision document presents the selected remedy for the Montana Pole and Treating
Plant site (the Site), in Butte, Montana. The Montana Depanment of Health &
Environmental Sciences (MDHES), in consultation with the United States Environmental
Protection Agency (EP A), selected the remedy in accordance with CERCLA, as amended by
SARA, and, to the extent practicable, the NCP. The EPA concurs and adopts the selected
remedy. The attached index identifies classes of documents or records that comprise the
administrative record upon which the selection of the remedial action is based.
:::
ASSESS:MENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by
implementing the response action selected in this Record of Decision, may present an
imminent and substantial endangerment to public health, welfare, or the environment.
DESCRIPTION OF THE SELECTED REMEDY
This is the fInal action for the only operable unit for the Site. The operable unit includes all
known sources and contaminated media at the Site. This action addresses the principal
threats remaining and provides for treatment of contaminated soils and groundwater. Some
treatment residuals and soils contaminated at lower levels will remain on-site, such that the
Site will require long-term management.
The principle contaminants of concern at the Site are pentachlorophenol (PCP), polynuclear
aromatic hydrocarbons (PARs), polychlorinated dibenzo-p-dioxins and polychlorinated
dibenzofurans. This Record of Decision establishes cleanup levels for these and all other
contaminants of concern at the Site. The major components of the selected remedy include:
1.
Excavation of contaminated soils from accessible areas of the site, to the
extent practicable. The volume of soils is estimated to be approximately
208,000 cubic yards;
2.
Treatment of excavated soils (208,000 cubic yards approximately) and
previously removed soils (10,000 cubic yards approximately) by above ground
biological treatment;
1

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7.
-.
8.
9.
:VI0NTA.~~A POLE ROD - DECLARATIOl\"
...
J,
In-place biological treatment of contaminated soils below the depth of
excavation before backfilling;
4.
Backfill (1'" excavated and treated soils into excavated areas if possible, surface
grading and revegetation:
5.
Soil flushing of inaccessible soils area.s (principally underlying Interstate
15/90) in order to recover hazardous substances;
6.
Containment of contaminated groundwater and LNAPL using physical and/or
hydraulic barriers (as detennined during remedial design) in order to prevent
the spread of contaminated groundwater and LNAPL and to limit releases of
contamination into Silver 'Bow Creek;
Treatment of extracted groundwator using the present EPA water treatment
plant (which consists of oil/water separation followed by granulated activated
carbon treatment). The ultimate design of the groundwater treatment system
(as determined during remedial design) may include the addition of biological
means or ultraviolet oxidation (UV/oxidation) to maximize cost effectiveness
of the treatment system. Treatment will meet standards for discharge or
reinjection, as appropriate;
Discharge of extracted, treated groundwater into Silver Bow Creek andlor
reinjection of extracted, treated groundwater into the aquifer (as detennined
during remedial design);
Enhanced in-situ biological treatmeDt o+' cc~taminated groundwater,
inaccessible contaminated soils areas and contaminated soils not recovered by
excavation;
10.
Treatment of contaminated site debris and equipment by decontamination
followed by disposal of these materials in a licensed off-site landfill;
11.
Treatment of contaminated oils and sludges in a licensed off-site incinerator,
12.
Additional institutional controls preventing access to cont;lminated soils and
groundwater, and
13.
Groundwater monitoring to determine movement of contaminan;s and
compliance with remedial action reqnirements. ... ,
Both soils and gfoundwater will be remediated at the Site. Soils will be excavated from four
. . ~~..i~'.. J
:2

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'. -..
~10~rrA..'iA POLE ROD - DECLARATION
general areas: surface soil hot spot areas, surface and subsurface soils in the fonner plant
process area, surface and subsurface soils along the histOric drainage ditch running from the
fonner plant process area to Silver Bow Creek and subsurface soils near the groundwater
table which have ueen contaminated by floating wood treating product. The selected
treatment technology for contaminated soils is above ground biological treatment. Some
contaminated soils and associated wood treating fluid will remain in place due to
inaccessibility and limits of excavation technology. These contaminated soils will be treated
in place by in situ biological degradation.
-","
Contaminated groundwater and any residual woodtreating fluids left after excavation, will be
contained from further migration using hydraulic and/or physical barriers. To create
hydraulic containment of contaminated groundwater, some contaminated water will be
extracted, treated and discharged to Silver Bow Creek. Other extracted and treated water
will be reinfl.ltrated on-site to assist in hydraulic containment, flushing of contaminated areas
and in situ biological degradation. Extracted groundwater will be treated above ground in
the water treatment plant constructed at the site by EPA. This facility presently consists of
oil/water separation and granulated activated carbon treatment. The ultimate design of the
groundwater treatment system may include the addition of biological means or ultraviolet
oxidation (UV/oxidation) to maximize cost effectiveness of the treatment system.
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the environment, complies with
federal and state requirements that are legally applicable or relevant and appropriate to the
remedial action, and is cost-effective. This remedy uses permanent solutions and alternative
treatment (or resource recovery) technologies to the maximum extent practicable and satisfies
the preference for remedies that employ treatment that reduces toxicity, mobility, or volume
as a principal element. Because this remedy may result in hazardous substances remaining
on-site above health based levels, the five year review will be conducted within five years
after commencement of remedial action to ensure that the remedy continues to provide
adequate protection to human health and the environment.


B~~ Date0jA3

Montana Department of Health & Environmental Sciences
il {
vI;! / j J :
W. McGraw, ActIng Regional Admin.istrntor
ironmental Proteetion Agency, Region VIII
y~t/f3

I
Date
'"
.j

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-"
~
DECLARATION

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:\'IONTA."tA POLE ROD - DECISIO~ SCvL\.L-\RY
SITE NA."IE. LOCATIOI"' ..\1'11) DESCRIPTION
h
-'
Montana Pole and Treating Plant
Butte, Montana
The Montana Pole and Treating Plant site is located at 202 West Greenwood Avenue, on the
western edge of Butte, Montana, in the southeast quarter of Section 24, TIN, R8W (see
Figures 1 and 2). Generally, the site is bordered on the north by Silver Bow Creek, on the
south by Greenwood Avenue, on the west by a former smelter site and on the east by a
railroad right-of-way. U.S. Interstate 15/90 runS across the site in an east~west direction
and partitions the site into a northern and a southern section. portions of the Site lie within
the 100 year floodplain. The Lower Area One (LAO) Operable Unit of the Butte/Silver Bow
Creek Superfund site overlaps the Site on the north.
,.'
The Site is located in a mixed land use area. Mu.:h of the land in the vicinity of the Site has
been used industrially, usually associated with past and present mining activities, though
commercial and residential areas are immediately adjacent to the Site. Two neighborhoods
are within a quarter mile of the site. There is one residence, an auto body shop and an
architect's office located on site. Groundwater use in the area is limited. In the residential
area east of the site, there is one well which is currently being used for domestic purposes.
The Mount Moriab cemetery south and up gradient of the site uses groundwater for lawn
watering.
TI.
SITE HISTORY
The Montana Pole and Treating Plant operated as a wood treating facility from 1946 to 1984.
During most of this period, a solution of about five percent pentachlorophenol (PCP) mixed
with petroleum carrier oil similar to diesel was used to preserve poles, posts and bridge
timbers. The PCP solution was applied to wood products in butt vats and pressure cylinders
(retorts). Creosote was used as a wood preservative for a brief period in 1969.
The plant initially included a pole peeling machine, tWo butt treating vats, and related
ancillary facilities. In April 1947, the first load of treated timbers was shipped off-site.
Major modifications to the plant occulTed betWeen 1949 and 1951, and again around 1956.
Sometime betWeen 1949 and 1951, a 73-foot-long, 6-foot-diameter retort was installed to
increase timber treatment production efficiency. A second retort, which was 66 feet long
with a 7-foot diameter, was installed around 1956. The retorts were used both to dry green
timber using the Boulton process, and to pressure treat timber with a
petroleum/pentachlorophenol (pCP or penta) mixture. Drying timber by the Boulton process
genercited steam which was condensed. The condensate was discharged to tWo hot wells. '
where the condensate panially separated into an oil and water phase. The water phase from
the hot wells was reportedly discharged into an on-site unlined drainage ditch which flowed.
1

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'c --
.YIONTANA POLE ROD - DECISION Sl"'\[\lARY
northward toward Silver Bow Creek. On-site sedimentation ponds were also apparently used
for waste disposal purposes.
The retOrts and bun treatment vats were in continuous operation umil May 1969. On May 5,
1969, an explosion occurred while a charge of poles was being treated in the east bun
treating vat. The explosion generated a fIre which destroyed the east vat, boiler room. and
retort building. Although the boiler, retOrts, and auxiliary equipment were damaged. the
plant was rebuilt and functional by December 1969. The west butt treatment vat was not
destroyed by the fIre and was thereafter used for some timber treatment and mixing the
petroleum/PCP product used in the retorts. Petroleum/PCP product reportedly spilled from
the east butt treating vat as a result of the explosion and fIre. Additional seepage of product
occurred from both retortS as a result of broken pipes and valves damaged by the fIre.
Reportedly, on-site tanks were not ruprured as a result of the fIre.
...
A small on-site sawmill was constructed in the fall of 1978 and was fully operational by the
fall of 1979. Additionally, in response to implementation of the Resource Conservation and
Recovery Act (RCRA), a closed-loop process water system was constructed in 1980. The
primary function of this sYStem was to eliminate overland discharges of Boultonizing water
(generated from the drying of green timber). The closed-loop water recovery system
operated by collecting wastewater in stornge tanks, recirculating this water through the
condensing syStem, and evaporating excess warer using aeration sprnys.
On May 17, 1984, the Montana Pole and Treating Plant ceased operations.
Enforcement Actions
In March 1983, a citizen fIled a complaint conceming oil seeping into Silver Bow Creek near
the Montana Pole facility. MDHES investigated the complaint and discovered an oil seep on
the south side of Silver Bow Creek directly downgradient from the Montana Pole facility.
Further investigation of the site revealed oil-sanmued soils adjacent to the creek and on
Montana Pole property. Subsequent sampling ronfumed the presence of PCP, polycyclic
aromatic hydrocarbons (PARs), and dioxinslfw:ans in site soils and oil samples. MDHES
and EPA completed a preliminary assessment ami site inspection (pA/SI) followed by a
Hazard Ranking Score in July 1985. The Moutma Pole facility was included on the National
Priority List for Superfund sites on July 22, 1981 (Fed. Reg. Vol. 52, 140 Pg. 17623).
In July 1985, the EPA Emergency Response BI2DCh began conducting a removal action on
the site to minimize impacts to Silver Bow creet and to stabilize the site. EP A excavated
approximately 10,000 cubic yards of highly cODtm1inated soils. bagged them and placed them
in storage buildings (pole barns) constructed on site. Tanks, retons, pipes and other
hardware were dismantled and stored on site in a former sawmill building. Two
groundwater interception/oil recovery systems were inStalled to alleviate oil seepage into the
2

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MONT..\J.~A POLE ROD - DECISION S"L~liY1ARY
creek. Contaminated ar~as of the site and featUres of the groundwater recovery system were
fenced to restrict public acc~ss.
In OctOber 1989 EPA granted MDHES the initial enforcement funding to conduct potentially
responsible party (PRP) noticing and administrative order negotiations and issuance. In April
1990 MDHES signed an administrative order on consent with ARCO under which ARCO
agreed to conduct a remedial investigation and feasibility stUdy (RIfFS) at the site. In June
1990, ARCa began the RlIFS following the MDHES and EPA approved RIfFS work plan.
The remedial investigation complied with Superfund law, defmed the natUre and extent of
contamination and provided information to complete the baseline human health and ecological
risk assessments. The feasibility srudy included the development, screening and evaluation
of potential site remedies.
..>
In June 1992, the USEPA proposed an additional removal action to control and recover the
light non-aqueous phase liquid (LNAPL) (floating oils) identified during the RI. The action
included the installation of a 890 foot sheet piling on the south side of Silver Bow Creek.
The sheet piling is approximately 50 feet south of the creek. Ten recovery wells were
inStalled on site. Eight of the wells are located south of Silver Bow Creek in a north/south
line running pexpendicular to the creek. Two wells were installed parallel to the creek; one
on each end of the sheet piling. The wells are approximately 25 feet deep. Each well has
tWo pumps: one to collect free-floating oil and pump it to an on-site storage tank and the
other to pump contaminated groundwater to an on-site granular activated carbon treatment
facility built by EPA. The water treatment facility went into operation January 22, 1993, at
which time the system installed in 1985 was shut down. In October, 1993, it is likely that
EP A will implement limited soils excavation as part of its removal response.
3

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MONTA.J.~A POLE ROD - DECISION S17MNIARY
illGHLIGHTS OF COI\1ll\;fUNITY PARTICIPATION
)TI.
Public panicipation is required by CERCLA. sections 113 and 117. These sections require
that before adoption of any plan for remedial actioo to be undertaken by the President (EPA)
or by a State (MDHES) or by anyone (pRPs), :he lead agency shall:
1.
Publish a notice and brief analysis of the Proposed Plan and make such plan available
to the public; and
2.
Provide a reasonable opportunity for submission of written and oral comments and an
opportunity for a public meeting at or near the Site regarding the Proposed Plan and
any proposed fmdings relating to cleanup stlndards. The lead agency shall keep a
transcript of the meeting and make such tIanscript available to the public. The notice
and analysis published under item #1 shall include sufficient information to provide a
reasonable explanation of the Proposed Plan and alternative proposals considered.
..,..
Additionally, notice of the final remedial action plan (Record of Decision) adopted shall be
published and the plan shall be made available to the public before commencing any remedial
action. Such a final plan shall be accompanied by a discussion of any significant changes to
the preferred remedy presented in the Proposed Plan along with the reasons for the changes
and a response (Responsiveness Summary) to each of the significant comments, criticisms,
and new data submitted in written or oral presemations during the public comment period.
. MDHES has conducted required community participation activities through presentation of
the Proposed Plan, a 60 day public comment period, a public hearing and presentation of the
selected remedy in the Record of Decision. Specifically included with the Record of
Decision is a Responsiveness Summary that summarizes public comments and MDHES
responses. The Record of Decision documents changes to the preferred remedy as a result of
public comments.
The Proposed Plan for the Site was released for public comment on May 5, 1993. The
Proposed Plan was made available to the public ill both the administrative record located at
the Montana Tech Library in Bune and at MDHES offices in Helena, MT, and infonnation
repositories maintained at MDHES offices in Hek:aa, the Montana Tech Library, the Butte
Public Library, the Butte EP A Office and the Stale Library in Helena. The Proposed Plan
was distributed to the MDHES Montana Pole Site mailing list. The notice of availability of
the Proposed Plan was published in the Butte-MODIaIla Standard newspaper on May 7, 1993.
A public comment period was initially designated from May 7, 1993 through June 7,1993,
but requests resultd in a 30 day extension to July 7, 1993.
A public hearing was held in Butte, Montana on May 27, 1993. At this hearing,
representatives from EPA and the MDHES answ.:red questions about problems at the Site
4

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. -.
MONTAL~A POLE ROD - DECISIO:\ S"L-:\1LVlARY
and the remedial alternatives under consideration as well as the preferred remedy. A portion
of tlfe. hearing was dedicated [0 accepting formal oral comments from the public. A court
reporter transcribed the entire hearing and MDHES made the transcript available by placing
it in the administrative record. A response to the comments received during the public
comment period is included in the Responsiveness Summary, which is part of this Record of
Decision. Also, community acceptance of the selected remedy is discussed in section VII,
Summary of Comparative Analysis of Alternatives, of the Decision Summary.
--
5

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K
MONTA!.'lA POLE ROD - DECISION SL~Dl-ill.Y
SCOPE Al~1) ROLE OF RESPONSE ACTION
':11e primary focus of the MPTP RIfFS was to evaluate findings of previous investigations, to
collect additional infonnation to assist in characterizing current and future risks, and to
develop and evaluate long tenn and pennanent remedial action alternatives. The RIfFS was
perfonned in accordance with the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP) 40 CFR Part 300, and CERCLA Section 104, 42 D.S.C. ~ 9604.
The overall objectives of the RIfFS were:
~
o
To collect infonnation on the types, concentrations, extent and movement of
contaminants present in subsurface soils, surface soils, surface water,
sediment, groundwater, oils, sludges, and dismantled equipment at the site;
o
To provide information fer estimating the volume of contaminated media and
materials;
o
To provide information on site physical characteristics and site contaminants
for use in the Risk Assessment, the Feasibility Study, and the Remedial
Design;
o
To collect data for use in treatability studies during the FS and RD;
o
To collect data on geotechnical properties for use in designing and locating
remediation structures during the RD;
o
To identify potentially applicable or relevant and appropriate regulations
(ARARs) for response actions; and
o
To identify and evaluate remedial alternatives to address human health and/or
environmental risks.
Based on the evaluation of the wood treating operations, fmdings of previous investigations
and the results of the RI field investigation, the sources and the areas of environmental
contamination at the Montana Pole site have been adequately delineated.
The remedy outlined in this Record of Decision represents the fmal remedial action at the
site and will address the principal threats to human health and the environment which are
posed by the contE..minated media and materials.
6

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:\tlOl'l!A1~A POLE ROD - DECISIO~ S'L-:YLVL-\RY
Sl:~1MARY OF SITE CH.-\RACTERISTICS
v.
.,'
The following section discusses the principle contaminants of concern found at the site,
summarizes the narure and extent of site contamination, provides a brief discussion of
contaminant fate and transport at the site and provides estimated volumes of contaminated
materials at the site.
Princiole Contaminants of concern
Hazardous substances that have been released at or from the Site, but are not limited to,
include the following:
Pentachlorophenol and other chlorinated ohenols
...
A mild acid with an hydroxyl group, pentachlorophenol (PCP) is a hazardous substance 1S
defmed by CERCLA 9 101(14). Pentachlorophenol ionizes in solution to form
pentachlorophenate anion. The pH dependent ionization leads to higher solubility for
pentachlorophenol than its normal aqueous solubility of 14.0 mg/L. Once pentachlorophenol
dissolves in water, its adsorptive behavior begins to conttOl its fate. ~ aqueous solubility
decreases, the adsorption increases. Groundwater pH is generally in the neutral range at the
Site, rendering pentachlorophenol more mobile in groundwater than the other contaminants of
concern. Site aquifers are comprised of fairly transmissive sands and gravels, resulting in
rapid migration of pentachlorophenol.
Pentachlorophenol is known to be biodegradable under both aerobic and anaerobic
('')nditions. Anaerobic degradation rates are generally 10 to 100 times slower than aerobic
degradation; therefore, if remediation time is critical, a method of oxygen enhancement is
recommended (Woodward-Clyde, 1988). Other related chlorinated phenols have been
identified at the Site. Chlorinated phenols are present in pentachlorophenol as manufacturing
byproducts. They may also result from breakdown of pentachlorophenol. Pentachlorophenol
is identified as a probable human carcinogen.
Polynuclear aromatic hvdrocarbons
Several polynuclear aromatic hydrocarbons (PAHs), defined as hazardous substances by
CERCLA 9 101(14), have been identified at the Site. These include: anthracene,
benzo(a)pyrene, benzo(a)anthracene, benzo(k)fluoranthene, benzo(b)fluoranthene,
dibenzo(a,h)anthracene, indeno(c,d)pyrene, benzo(g,h,i)perylene, phenanthrene, chrysene,
fluoranthene, fluorene, naphthalene and pyrene. The majority of the compounds do not
contain active functional groups and have low aqueous solubilities.
The low molecular weight P AHs are comparatively more soluble in water than high
7

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MONTANA POLE ROD - DECISION Sl'NJ2VL\RY
molecular weight PARs and have lower organic carbon partition coefficients. Low
- molecular weight compounds are typically more mobile in the environment than the high
molecular weight PARs.
PAR compounds are known to be biodegradz ble under both aerobic and anaerobic
conditions. The rate of transformation of PAR compounds by soil microorganisms is related
to the compound's molecular weight as well as the acclimation of the soil microbes to the
:?AH compounds. Thus, the low molecular weight PAHs biologically degrade at a faster rate
than the high molecular weight PARs. The four ~d five ringed P AHs found at the Site are
suspected probable human (B2) carcinogens. The two and three ringed PARs found at the
Site are not probable human carcinogens; however, they can present noncarcinogenic health
hazards.
Polychlorinated dibenzo-p-dioxins and Polychlorinated dibenzofurans
Polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) are
hazardous substances as defined by CERCIA 9 101(14). PCDDs and PCDFs are a family of
aromatic compounds that are often byproducts of chemical manufacturing or combustion
processes involving chlorinated organic compounds and heat.
The biological degradation rate of these compolDJds is generally very slow when comvared to
other organic compounds. Because PCDDs and PCDFs have very low vapor pressures, they
do not readily evaporate or volatilize to the atmosphere. The compounds adhere tightly to
soil particles and do not migrate readily or leach into groundwater or surface water unless
the contaminated soil particles themselves migrale via erosion processes (Freeman, 1989).
1bis family of compounds includes suspected probable human carcinogens of varying
toxicity. One isomer, 2,3,7, 8-tetrachlorophenol dibenzo-p-dioxin (TCDD), has been
detennined to be the most toxic. Concentrations of the other less toxic isomers are
multiplied by toxicity equivalence factors to ~il\e their risk relative to 2,3,7,8-TCDD.
The toxicity equivalence for each PCDD and PCDF analyzed for a sample is added together
to result in one concentration value and the suIIJDaation is expressed as TCDD toxicity
equivalence (TE) which is used as the basis for determining overall health risks from these
compounds.
SummarY of Nature and Extent of Contami~n
A13 reported in the Final RI Report (ARCa, 1993a), seven different media were sampled
during the RI for the MPTP site. These media include: soils (surface, subsurface, and
removed), groundv'ater, surface water, sediments, process equipment, miscellaneous oils,
and miscellaneous sludges. The samples were typically analyzed for PCP, PAHs, 'total K.o :,...j,.C.
petroleum hydrocarbon (TPH), volatile organic compounds (VOCs), dioxinslfurans, and
metals. The removed soils and miscellaneous oils and sludges were also analyzed usin~ the
8

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MONTAJ.~A POLE ROD - DECISION St~[\L\.RY
TCLP method for metals and organics.
-'
Elevated levels of PCP, PAHs, TPH, and dioxins were detected in the surface and
subsurface soil samples collected from the plant process area and within and near the
historical dra lIlage ditch. Figure 3 presents PCP surace soil concentrations greater than
15,000 ug/kg. Figure 4 presents PCP subsurface soil concentrations above 10,000 ug/kg.
Figures 5 through 8 present PCP subsurface soil boring concentrations in cross section. The
maximum concentrations of PCP, TPH, and dioxins detected in the surface soil samples were
1,510,000 ILg/kg, 71,500 mg/kg, and 8.18 ILg/kg, respectively. The maximum
concentrations of PCP, P AH, TPH, and dioxins detected in the subsurface soil samples were
1,160,000 ILg/kg, 2,304,320 JLg/kg, 55,600 mglkg, and 11.36 JLg/kg, respectively. Elevated
levels of PCP and PAH were generally found to depths of 8 feet in the northern ponion of
the site and to depths greater than 15 feet in the southern portion of the site. PCP, PAR,
and TPH were detected in surface soil samples collected from the fonner eaStern and western
wood storage yards at relatively low concentrations. PCP, PAR, and TPH were not detected
in subsurface soil samples collected in the wood storage yards. The maximum concentrations
of PCP, PAR, TPH, and dioxins detected in the removed soils were similar to the maxllnum
concentrations detected in the surface and subsurface soils.
-"
Figure 9 illustrates the approximate lateral extent of groundwater, LNAPL and surface water
contamination associated with the MPTP site. PCP in the groundwater is fairly widespread
throughout the site. Figures 10 and 11 show PCP concentrations detected in groundwater
samples taken at and near the site. Figure 12 illustrates the estimated lateral extent cf site
PCP groundwater contamination at concentrations greater than 1 ugll. LNAPL was detected
in eight of the 39 wells sampled, although not all wells are screened at a depth that would
allow LNAPL to be measured. The maximum LNAPL thickness measured during the RI
was 2.2 feet in well W-8 which is located north of the pole barns. LNAPL thickness and the
estimated extent of LNAPL contamination is shown in Figure 13. Only floating
woodtreating product was found during the RI. No dense non-aqueous phase liquids
(DNAPLs) were found.
PCP, PAR, and TPH were detected in the surface water and sediment samples collected near
the oil seep locations on Silver Bow Creek. Figure 14 shows PCP, PAR and TPH surface
water concentrations in Silver Bow Creek. Figure 15 shows PCP, P AH and TPH sediment
concentrations in Silver Bow Creek. The maximum concentration of PCP detected in the
surface water samples (591 ILg/I) was from the sample collected near the farthest downstream
seep. The maximum concentration of PCP detected in the sediment samples (1,820 ILg/kg)
Wa5 from the sample collected immediately downstream of the farthest downstream seep.
Metals (i.e., arsenic, cadmium, chromium, copper, lead, and zinc) were detected in soil,
groundwater, surface water and sediments at the site. Elevated metals concentrations were
generally found in associatiO'l with Silver Bow Creek and tailings deposits near the creek.
9

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MO~lAL'iA POLE ROD - DECISION SLyL\L\.RY
Ele\'ared metals concentrations are considered to be related ro historic mining activities in the
-viciniry of the site rather than any activities associated with the site.
Minimal wipe sampling was perfoI1I1ed on the pro~ss equipment. The maximum
concemntions of PCP, PAR, and 2,3,7,8-TCDD detected on the wipe samples (lOa cm1)
were 3 r.' J.Lg/wipe, 10.76 J.Lg/wipe, and 7.19 ng/wipe.
Approximately 26,000 gallons of oils and sludges are stOred on site (at the time the RI was
conducted) including oil recovered from the oillw.uer separator, oils treated by the KPEG
process, reagent sludge from the KPEG processing operntion, and miscellaneous oils and
sludges presumably collected from various tanks wed in the wood preserving operntions.
Elevated concentrations of PAHs, and VQCs were detected in all the oil and sludge samples.
Elevated concentrations of PCP were, detected in an but the KPEG treated oils and reagent
sludge samples. Low levels of PCDDs and PCDFs were detected in all but the KPEG
treated oils and reagent sludge samples.
Major Sources of Contamination from Historical MPTP Operations
Based on historical infoI1I1ation about fOITI1er MP1P operntions and data gathered during the
RI, the major sources of contamination from historic l\i!PTP operntions are discussed below
and include:
.
Plant process area;
Wastewater discharge ditch including the former waste sedimentation pond;
and
. LNAPL plume.
.
.
Plant Process Area. Two retorts and two butt treatment vats were located within the
plant process area, and spillage of product from tbz:se facilities during MPTP operations has
been reported (see Final RI Report, Section 1.2.2). Surface and subsurface soil samples
from the plant process area indicate the presence cL high concenttations of PCP and P AH
compounds. Some of the soils in this area are satmated with woodtreating chemicals and
petroleum carrier oils. In addition, PCP levels greater than 10,000 p.g/l have been detected
in groundwater beneath this area of the site, and 3D LNAPL layer is present on the water
, table.
Wastewater Discharge Ditch Area. Wastewater from the wood treating process was
discharged into on-site sedimentation pond(s) and 3D on-site drainage ditch. PCP mixed with
petroleum (PCP/oil) was used to treat timber during the time these discharges occurred.
- .
The drainage ditch flows northward through the sitIC toward Silver Bow Creek (see Figure 2).
10

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MO~"T~'i'A POLE ROD - DEClSIO~ Sl.~[\l.\RY
Soil was excavated from portions of the ditch to a depth of up to 6 feet as part of EPA's
rema"vaI actions. Sampling conducted during the RI indicates that soils and groundwater
beneath the drainage ditch are heavily contaminated throughout :ts length. Depth to
groundwater varies along thp length of the drainage ditch. Groundwater is about 20 feet
below grade near Greenwood Avenue: about 8 feet below grade beneath the interstate; and at
about 2 to 4 feet below grade near Silver Bow Creek.
L'lAPL Plume. As shown on Figure 13, an LNAPL plume consisting of PCP
dissolved in petroleum carrier oils, extends from ~e fonner process area to Silver Bow
Creek. Tne LNAPL is a result of former MPTP waste disposal practices and spillc;.ge of
woodtreating chemicals. The RI indicated that LNAPL is discharging to Silver Bow Creek at
several seep locations, and chemicals of concern are dissolving intO groundwater from the
LNAPL plume. No DNAPLs were found at the site.
Conceotual Model of Contaminant Fate and Tra:-"=Dort
-::
A conceptual model was developed and presented in the final RI report and provides an
overview of site contaminant fate and transport as it existed during the RI (Figure 16). The
conceptual model describes the relationship betWeen source areas, migration pathways, and
potential receptors. PCP, PAHs, dioxins, and furans at the MPTP site'have entered the
environment from several source areas by spillage, leaks, or infIltration and have migrated
via various transport pathways (e.g., advective flow with the groundwater). A detailed
discussion of the chemical and biological processes and an estimate of the rates of migration
of different contaminants in the subsurface are presented in the Final RI Report (ARCa,
1993a) .
Estimated Volumes of Contaminated Materials
In the Final FS Report (ARCa, 1993b), estimates were made of contaminated site soils,
groundwater, LNAPL, oils, sludges, equipment and debris. The agencies believe that these
estimates were adequate for the purposes of the FS and remedy selection. However, it is
recognized that more accurate volume estimates may be required for remedial design.
Site Soils
The estimated volumes of contaminated site soils at the site are shown in Table 1. These
volumes include previously removed soils that are stored in pole barns at the site, in place
contaminated soils, and uncontaminated soils which would require removal to access
underlying contamination. Figures 17 and 18 show the locations 0f the in piace ~ontaminated
soils at the site. .
V olumes estimates were developed:
11

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MONTANA POLE ROD - DECISION SL-Y[\L\RY
-"
considering the remedial alternatives developed:
using PCP as an indicator compound;
using the PCP Preliminary Remedial Action Goal of 3 mg/kg;
using phy~ical parameters, as discussed below, for determining the location
and accessibility of these contaminated soils.
PRAGs were developed based on information developed in the Baseline Risk Assessmenr and
are presented in Table 2. DHES found little difference in soil volumes estimated for the 3
mg/kg PRAG and the 34 mg/kg PRAG. This may be because soil contamination at the
MPTP site is generally associated with contact with wood treating chemical "solutions and
PCP concentrations in soils were generally found well above 3 mg/kg or well below 3
mg/kg.
...
The volume of previously excavated soils preser:+'y stored on site is approximately 10,000
yd3. Volume estimates of soils removed near Silver Bow Creek and soils removed for
installation of a groundwater treattnent system were estimated for use under various remedial
approaches. It is estimated that about 6,000 yd3 of soils near the creek would require
excavation and treatment. This volume calculation assumes all the soils north of the sheet
piling installed by USEPA in September 1992 would be excavated to a depth of 4 feet below
grade. The volume 01' soils estimated to be excavated during installation of the groundwater
extraction and treatment system is approximately 7,000 ydJ.
Volume estimates of additional contaminated in-pJace site soils include surface soils and
subsurface soils including soils impacted along the LNAPL plume. Areas where
contamination was found above the 3 mg/kg PCP PRAG in surface soils but not in
subsurface soils are shown in Figure 17 and consist of "he: spot" areas in the east and west
treated wood storage yards and soils near the fonner process area. The volume of these soils
is assumed to extend from the ground surface to 3 feet below ground surface and is estimated
to be 10,000 yd3. The actual depth of contaminarion in these areas will be detennined during
the remedial action.
Areas where contamination was found above the 3 mg/kg PCP PRAG in both the surface and
subsurface soils, down to the groundwater table are shown in Figure 17. This includes the
former process area, the former waste water draiDage ditch running from the process area to
Silver Bow Creek and areas adjacent to the drainage ditch on the north side of the interstate.
The volume of soils in these areas is estimated to be 82,000 yd3. This volume assumes that
contaminated subsurface soil concentrations above PRAGs extend to approximately 4 feet
below the groundwater surface. This depth is based on the RI data which showed that
subsurface contamination above the 3 mg/kg PCP PRAG extends approximately 4 fee: below
groundwater in these areas and other areas affected by the LNAPL plume. The volume of
these soils located beneath the highway is estimated at 4,000 yd3.
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MONTANA POLE ROD - DECISION Sl~L\'L.\RY
In other areas of the site subsurface soils have been impacted by the floating LNAPL layer.
.This area of LNAPL influence extends from the former process area to Silver Bow Cre~k.
LNAPL volume of 370,000 gallons has been estimated based upon the inferred LNAPL
plume shown in Figure 13. The extent of the inferred LNAPL plume is based on the
presence of LNAPLs in a number of wells and borings on the site. Within this area, a
"smear zone" where LNAPL has contacted subsurface soils near the groundwater table has
been estimated to extend venically 2 feet above and 4 feet below the groundwater surface.
Contaminated subsurface soils associated with the LNAPL plume in this area underlie
uncontaminated soils. The volume of these uncontaminated soils have also been estimated
and are presented on Table 1. In order to excavate contaminated soils associated with the
LNAPL plume, the overlying soils would also require excavation. Separation of clean and
contaminated soils during the remedial action would be important to minimize the volume of
soils requiring treatment. Excavation of soils beneath the interstate highway is considered to
be infeasible. Contaminated soils beneath the highway will be left in place and addressed by
other methods.
->
The volume of accessible contaminated subsurface soils associated with the LNAPL plume is
estimated at 93,000 yd3. This volume is in addition to the 82,000 yd3 surface/subsurface
volume estimate. The volume of contaminated subsurface soils associated with the l.l'lAPL
plume which are considered inaccessible beneath the highway is estimated at 37,000 ydJ.
This volume is in addition to the 4,000 ydJ within the drainage ditch beneath the highway.
The volumes of uncontaminated soils overlying the LNAPL plume are estimated to be 28,000
yd3 in the area nonh of the highway and 66,000 y& in the area south of the highway.
Groundwater
The areal extent of contaminated groundwater above the MCL for PCP of 1 JIog/L is
estimated to be 1.8 million square feet. Assuming an average aquifer thickness of 22 feet
and a porosity of 30 percent, the tOtal volume of alluvial groundwater cont::.minated above
the MCL was estimated to be approximately 90 million gallons. This volume represents the
volume of groundwater contaminated above the ~'{CL in place. This value is substantially
lower than the volume that would be treated by a pump-and-treat system.
Equipment and Debris
A rough estimate of the volume of equipment and debris on site was performed for the FS.
It is estimated that there is about 9,100 cubic yards of debris on-site which consists of wood,
soil cuttings, concrete, steel, and brick. A sampling program should be undenaken as part
of remedial design to determine more accurately the volume of debris and ext~nt of
contamination prior to disposal.
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:YIONTANA POLE ROD - DECISION S'l-:YLYL-ill.Y
Oils and Sludges
-"
Approximately 6,300 gallons of untreated oily wastes from the oil/water separator process:
9,000 gallons of KPEG-treated oil; 2,200 gallons of KPEG-reagent sludge; and 3,000 gallons
of misce llaneous oily wastes and sludge are eStimated to be stored in drums and storage tanks
at the MPTP site (ARCO, 1993a). Keystone (1991a) assumed that the total quantity of oily
wastes and sludge requiring remediation was approximarely 26,500 gallons. Additionally, it
is estimated that betWeen 3,000 and 6,000 gallons of oily wastes would be generared each
year in the first few years of operation of a combined groundwater and LNAPL recovery
system likely to be used for this site. The quantitY of LNAPL recovered from the
groundwater systems annually will decrease over time.
-
14

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:Y!ONTA.L'iA POLE ROD.. DECISION Sl-:Y[\L\RY
VI.
SUMM..<\..R Y OF SITE RISKS
- "
The Baseline Risk Assessment (CDM, 1993) provides the basis for taking action and
indicates the exposure pathways that need to be addressed by the remedial action. It serves
as the b2seline for indicating what risks could exist if no action were taken at the Site. This
section of the Record of Decision repons the results of the Baseline Risk Assessment
conducted for this Site.
As pan of the remedial investigation and feasibility srudy, human health and ecological risk
assessments, which together comprise the Baseline" Risk Assessment, were developed to help
MDHES and EP A determine actions necessary to reduce actual and potential risks from
hazardous substances at the Site. Risk assessments were conducted at the Site with the
foUowing objectives:
o
provide an analysis of baseline risk (potential risk if no remedy occurs) and
help determine the need for action;
..,
o
provide a basis for determining cleanup levels (concentrations) that are
protective of public health and the environment;
o
provide a basis to compare potential public health and ecological impacts of
various cleanup alternatives; and
o
provide a consistent process to evaluate and document potential public health
and ecological threats at the Site.
The Baseline Risk Assessment indicates that the principal threats stem from contaminated
groundwater, releases of contaminated groundwater and oily wood treating fluids into surface
water, and surface soils. The primary human health risk exposure pathways are ingestion of
and direct contact with contaminated groundwater and ingestion of or direct contact with
soils. Potentially affected receptors include residents, workers, trespassers, recreational
users, and terrestrial and aquatic biota.
Human Health Risks
The Baseline Risk Assessment indicates that there are excessive hum
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MONTANA POLE ROD - DECISION SL~l\tL\RY
humans or laboratory animals (when human data were unavailable), their maximum
- concentrations measured in each media, and their frequency of detection. The same
screening criteria applied to soil and groundwater were also applied to surface water and
sediment. This made the screen very conservative for these media, since it is unlikely that
exposures to either surface water or sediment w.;mld occur over an extended time period on a
daily basis.
Based on the above described process and some special considerations, the chemicals listed in
Table 3 are considered contaminants of concern (COCs) for human health for the Montana
Pole site. '.
Exposure Assessment
-
Potential pathways by which human receptors could be exposed to contaminants at, or
originating from, the Montana Pole site are provided in Tables 4 and 5, and include
incidental exposure to soil, surface water and sediment, use of groundwater for domestic
purposes and consumption of vegetables grown in contaminated soils. In identifying potential
pathways of exposure, both current and likely future land use of the site and surrounding
study area were considered. Proximity to Silver Bow Creek and lack of access control for
much of the site suggests that trespassers may frequent the site and be exposed to
contamination. Past industrial use of the site suggests that future on site workers might be
exposed to site-related contaminantS while at work. Finally, past and present residential land
use and zoning allowances suggest the potential for future residential development. DHES
recognizes that efforts are being pursued by ARCa and Butte-Silver Bow government to
further resnict land use at the site.
...
The assumptions used to estimate potential exposure for workers, trespassers and residents
are shown in Tables 6 through 14. Exposure point concentrations for surface soils are shown
in Table 15, for groundwater are shown in Table 16 and for surface water and sediments are
shown in Table 17. The highest exposures were estimated for future on site residents, as
expected, because such individuals are expected [0 contact contamination more frequently
- than either workers or site trespassers. For resi~, exposure via the groundwater pathway
is much greater than for any other pathway. PoteDtial future use of the alluvial aquifer for
domestic purposes represents the highest exposure potential for the site. Chemicals for
which exposure is highest include pentachloropbeD>1 (PCP), the major wood-treating
chemical used on site, and P AHs which are constituents of creosote. Creosote was also used
to treat wood at the Montana Pole site for a brief period.
Toxicity Assessment
The purpose of the toxicity assessment was to examine the potential for each chemical to
cause adverse effects in exposed individuals and to provide an estimate of the dose-response
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MONTA.J.'lA POLE ROD - DECISION S'l,"YtVL-ill.Y
relationship betWeen the extent of exposure to a panicular contaminant and adverse effects.
..A.dverse effects include both noncarcinogenic and carcinogenic health effects in humans.
Carcinogenic Effects. Of the COCs for the site, several, including PCP,
dioxins/furans, 2,4,6-trichlorophenol, some PARs and arsenic, are known or suspected
human carcinogens. The most potent of these chemicals are the dioxins/furans. Some of the
PARs are also relatively potent carcinogens, though less so than the dioxins/furans. PCP,
for which site-related exposures may be greatest, is a less potent carcinogen than either
dioxins/furans or the carcinogenic PARs.
Noncarcinogenic Effects. The potential for COCs to produce noncancer effectS
varies widely. Dioxins/furans are extremely potent compounds, and only small exposures
may be associated with increased risk of adverse effectS. Other compounds, such as copper,
are relatively non-toxic, and only produce adverse effectS at much higher exposure levels. In
general, exposures estimated in this assessment for noncarcinogenic effects are sufficiently
low such that only the more potent toxicantS could present a significant risk.
Risk Characterization
Cancer Risk Estimates. To evaluate potential cancer health risks related to the
Montana Pole site, chemical exposures calculated are multiplied by cancer slope factors to
develop upper I3I1ge incremental lifetime cancer risks. Incremental cancer risks in the range
of 10-0 or less may be characterized as acceptable by the EPA depending on the nature of the
site and the CDCs.
Cancer risks for exposure to CDCs in groundwater are the greatest for any pathway. Only
futUre residentS are evaluated for this exposure (see T~bJ~ 18). Risks exceed 1 x 10.1, the
upper limit for risk predictions using current models. Significant risk is ~butable to PCP,
even though this chemical is one of the least potent carcinogens among the COCs. This
fmding attestS to the very high concentrations of PCP found in the groundwater beneath the
Montana Pole site. Dioxins/furans also contribute significantly to risks. These compounds
are expected cormminants of technical grade PCP which is used for wood treating.
The consumption of homegrown produce also contributes significant potential risk for future
residents (Table 18). Risks for this pathway, however, may be only about 1 percent of the
risks from drinking contaminated groundwater. This is due to a reduction in exposure
concentrntion for most COCs (produce concentrations are estimated to be less than soil
concentrations), and fewer days of exposure (the growing season in Butte is limited by
climate). Risks from exposure to PCP and dioxinslfurans are !he greatest for ~ pathway
(risks of 9 x 1~ and 1 x 104, respectively) for the southern area of the site. Exposures in
the northern area, betWeen the Interstate and Silver Bow Creek, had similar overall cancer
risk estimates, although the risks for individual compounds varied somewhat.
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ylONTAl'lA POLE ROD - DECISION Sl.-:\L.VL-\RY
Risks associated with direct contact with soil (incidental ingestion and dennal contact) are
-significantly less for all exposure scenarios than those estimated for groundwater and produce
consumption. However, for workers and trespassers, these pathways are major contributors
to overall risks, since groundwater and produce ingestion are not considered (Tables 19 and
20). Overall, cancer risk estimates for workers and trespassers are up to one thousand times
less than those for furure residents, and fall within the EPA risk range of 1~ to 1~,
Noncarcinogenic Health Risks. To evaluate non-cancer health risks, chemical
exposure is compared to one of several types of toxicity criteria to determine if the exposure
is within a range of exposure which is unlikely to 'cause adverse health effects. The potential
for noncarcinogenic health effects is evaluated by dividing a chemical-specific exposure level
by a chemical-specific reference dose. The resulting hazard index (HI) assumes that there is
a level of exposure (RtD) below which it is unlikely for even sensitive populations to
experience adverse health effects. If the CDI exceeds the RID (i.e., HI> 1), a potential for
non-cancer health effects may exist. .
..,
The pattern for non-cancer risks is similar to that for carcinogenic risks. Risks are greatest
for furure residents and for groundwater and produce ingestion pathways. For groundwater,
dioxins/furans, non-carcinogenic PAHs and PCP all have hazard indices (HIs) exceeding
unity (533, 75, and 22 respectively, Table 18). Risks for adverse effects, which could
include effects on the liver, kidneys, adrenal glands and other organs may be significant for
these compounds. . .
For produce ingestion, His for dioxins/furans are smaller, but still exceed one. For example
the In for dioxins/furans is 6 (Table 18). However, because of a high estimate for PCP
absorption through plant roots, the In for PCP is higher (64) for this pathway. Only
anthracene among the P AHs is a COC for soil, and it is present in quantities too small to
present significant risk. The only other possible contributor to risk via this pathway is
arsenic (HI = 7).
For the direct soil contact pathways, risks (HIs) are substantially lower. For furure or
current residents, HIs for all chemicals are less than one, and no increased risk for adverse
effects is anticipated. Noncancer risk estimates for workers and trespassers are shown in
Tables 19 and 20.
Ecolmrlcal Risks
The ecological risk assessment (ERA) for the Montana Pole site evaluated the potential for
harm to terrestrial tlnd aquatic populations following exposure to contaminantS. Silver Bow
Creek is presently degraded by metals contamination and does not support a viable fishery.
The risk assessment concluded if Silver Bow CI..ek is remediated for metals contamination
the presence of site cont.aminants could inhibit the recovery of aquatic populations (fish) in
18
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~10NTA..'iA POLE ROD - DECISION Sl~[\'L\RY
the stream.
-'
Contaminants of Concern
From the list of chemicals expected to occur at the Montana Pole site, seven chemicals or
chemical groups are selected for evaluation in ~he BRA. These chemicals were:
.
Polycyclic Aromatic Hydrocarbons (PARs)
Pentachlorophenol (PCP)
DioxiniFurans
Arsenic
Cadmium
Copper
Zinc
.
.
.
.
.
.
'.'
Potential Receptors
Aquatic Communities. Silver Bow Creek adjacent to the Muntana Pole site and .
downstream to the Wann Springs Ponds does not support a fishery population. Wests lope
cutthroat crout (Oncorhynchus clarki Lewisi) and bull trout (SaLvelinus confluenru.s) are
reported to have once been caught in the vicinity of Butte prior to intensive mining activities.
Prior to 1975, severe mining-related pollution in much of the upper Clark Fork River Basin
drainage had rendered the system incapable of supporting a viable fishery. Excessive metals
deposits still prevent the establishment of a fishery in Silver Bow Creek.
Benthic invertebrate communities and algae have re-established themselves within the study
area since the cessation of direct mine waste water discharges to Silver Bow Creek.
Mayflies, caddis flies, and stoneflies have been collected, although they demonstrate low
density and limited diversity. No known surveys on benthic communities have been
conducted within the study area since about 1984. The current density and diversity of this
aquatic community is unknown.
Ten-Qtrial Communities. No terrestrial communities within the Montana Pole site
were identified as critical habitat or communities of special concern. No rare or endangered
plants were identified within the study area boundaries of the Lower Area One (LAO)
Opernble Unit of the Silver Bow Creek NPL site, nor downstream of this study area.
Vegetation growin~ adjacent to Silver Bow Creek within the Montana Pole site is limited to
willows (Salix exigUil) and grasses. Shrubs indicative of dry conditions are fc.und throughout
the area. . .
.' .
.;!., . - . ,),.
19
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'.. -...
~IONT..\."JA POLE ROD - DECISIO;-'; SL~L\L\.RY
-.
Ecological Toxicity Assessment
Toxicity assessment is. typically comprised of tWo elements. The first, hazard identification.
is intended to characterize the narure and extent of biota health hazards associated with
chemical exposures. The second, a dose-respon ie assessment, determines the relationship
between the magnirude of exposure to a chemical and the OCCUITence of adverse health
effects. For the Montana Pole site, each chemical of conc::=rn was evaluated for toxicity
Val.les for use in risk characterization.
Ecological Risk Characterization
The ecological risk evaluation is similar to human risk evaluation, in that exposure
assumptions and toxicological data are combined with site data to estimate risk. However,
nonhuman receptors vary greatly in physiology and behavior, and thus it is difficult to .
quantify risk. Thus, the ecological risk assessment was a qualitative discussion of potential
risks and how these risks might affect biological receptors at the Montana Pole site.
Risks to Aquatic Life. Metals and arsenic found in sediments and surface water in
Silver Bow Creek may be a primary reason for tbe lack of diversity aDd productivity of the
reaches of Silver Bow Creek adjacent to the site. Elevated concentrations of these
contaminants are considered a result of historical mining activity in the upper reaches of the
Silver Bow Creek drainage. The Montana Pole wood treating plant is not considered to be a
source of metals contamination in the area.
Dioxins/furans, PARs and PCP have all been detected in surface water and/or sediments in
stteam reaches adjacent to the Montana Pole site. A seep where groundwater and LNAPL
discharge into the creek was detected visually near the location of surface water sampling
station SW-05. Thus chemicals are currently being released to surface water, and may pose
a threat to aquatic life.
The stress on the Silver Bow Creek system from inorganic contamination limits the potential
receptors for exposure to organic chemicals. In particular, the lack of fish greatly shonens
the aquatic food chain by eliminating higher troplric levels. Further, lack of food sources
(aquatic plants, insects and other invenebrares, sma.ll fish) make upper Silver Bow Creek
unattractive for larger animals such as migratory water fowl or raptors. Under current
conditions, it is unlikely that such animals would spend any significant time in stretches of
the creek near the Montana Pole site;. Any impaa of organic contamination from the
Montana Pole site should be considered potential, especially when such impacts are due to
hypothetical biomagnification of chemicals near the top of the food web. However, once
Silver Bow Creek has been remediated in association with the heavy metals contamination,
and the aquatic food chain is re-established, there will be a potential threat associated with
the organic chemicals. It is therefore necessary to address both inorganic and organic
20
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. -.
MONT~'lA POLE ROD - DECISIO~ Sl.~'LYL-\RY
contamination of the Creek to once again establish aquatic life in the Creek.
-'
Concentrations of PCP detected in surface water exceed both the acute (8.9 ug/l at pH of
7.0) and chronic (5.6 ug/l at pH of 7.0) ambient water qualiry criteria (AWQC). Water
concentrations of PCP measured as high as 591 l.Lgil could limit the recovery of aquatic life
in the impacted stretch of the creek.
PAHs, including lower molecular weight compounds such as anthracene, pyrene and
naphthalene, are present only in low concentratio~s even at the area of the seep. The highest
concentration reported was 12.7 j.Lg/L for acenaphthene. Acute and chronic to.<.iciry values
for acenaphthene and many other PARs are not available, however, the concentration of
P AHs in surface water at the Montana Pole site and downstream of the site are below
observed chronic toxicity values for aquatic organisms. Although individual P AHs are not
specifically addressed in this assessment, the generally low concentrations found in surface
water and sedimentS suggest that a more refmed assessment would reach similar conclusions.
For this reason, PAHs are discussed only as a group, even though individual members of the
group vary considerably in their tOxicity to aquatic life.
Risks to Terrestrial Life. Because organic cac concentrations appear to diminish
rapidly with distance downstream from the Montana Pole site, potential future impacts from
Montana Pole site-related chemicals are likely to be limited to a short reach of stream
starting at the region of 9ischarge of contaminated groundwater. Wildlife and/or domestic
animals using the downstream portions of the creek as a drinking water source are not
expected to be exposed to significant concentrations of organic eoes, unless discharge of
contaminated groundwater significantly increases.
Significant exposure of major wildlife species to surface water, sedimentS, and soils in the
impacted reach of the creek are also unlikely. The Montana Pole site is heavily diStUrbed by
past human activity, and is surrounded by residential housing, indusaial development, a
cemetery and an Interstate freeway. The site is unlikely to be attractive to wildlife, and
larger animals (predators, deer, elk) are not expected to use the site, or the adjacent reach of
the creek.
21
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-:,.,.
vn.
:VIO~"TANA POLE ROD - DECISION S"'L~L\;1ARY
DESCRIPTION OF ALTER.'," A TIVES
- .
A brief description of the site cleanup alternatives the agencies considered in the Feasibility
Study report follows. The estimated present worth cost of each alternative includes capital
cost and annual operation and maimenance cost. Remedial action time frames are limited [0
30 years for analysis, even for those alternatives requiring perpetual operation and
maintenance.
The cleanup alternatives presented in the Feasibility Study report were developed before EPA
constructed the groundwater treatment system which carne on line in January 1993.
Therefore the assumed design and costS of the alternatives do not incorporate the EP A
system in their design. However, the presence of the EP A system was addressed in the FS
and potential use of the system was considered. Utilization of the EP A groundwater
treatment system will reduce the overall costs (presented below) for the alternatives which
include groundwater treatment systems.
Alternative 1: No Action
Estimated present worth cost: $ 2,310,000 to S 2,350,000
Implementation time: Not Applicable
Superfund law requires that agencies coosider the no action alternative. This
alternative is used as a baseline against which 10 compare the other alternatives. Under
Alternative 1, no further action (other than the EPA's removal actions currently being
conducted at the site) would be undenaken. Contaminated soils, oils, sludges, equipment
and debris would remain on site. Contaminatioo would continue to migrate and impact
groundwater and Silver Bow Creek. Only the allrent fence (installed as part of EPA's
removal actions) would limit trespasser access 10 the site. Existing institutional controls
would allow most types of land uses. The costs for the no-action alternative are associated
with maintaining operation of the existing groUDdwater containment and treatment system and
continued administration of institutional controls for a period of 30 years. Actual costs and
effortS associated with the no action alternative ",ould be incurred indefInitely beyond the 30-
year period.
.- .
Alternative 2: Additional Institutional Controk and Groundwater Monitoring
Estimated present worth cost: $ 3,270,000 to $ 4,400,000
Implementation time: 1 year institutional control
30 + years operatioos and maintenance
This alternative would involve implemenring institutional controls in an attempt to
limit human exposure to contaminants. Additional institutional conn-oIs, beyond those
currently in existence, would be implemented to further restrict the development of site land.
These controls could include deed restrictions tbat prevent residential development and
..-
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MO~lA~~A POLE ROD - DECISION St.~L\lARY
construction activities in contaminated areas and modifications to the zoning laws and
building codes. The zoning laws would have to be modified such that certain land uses
iI1c1uding kennels, stables and stockyards would be prohibited. Building codes could be
modified to restrict construction depths to less than the depth of the water table. Only the
currenr fence (installed as pan of EPA's removal actions) would limit trespasser access to the
SHe.
The EPA's groundwater controls currently being conducted at the site would continue.
Contaminated soils, oils, sludges, equipment and debris would remain on site.
Contamination would continue to migrate and impact groundwater and Silver Bow Creek.
This alternative would include monitoring of downgradient (the groundwater equivalent of
downstream) and vertical migration of dissolved groundwater contamination and LNAPL.
The costs for Alternative 2 are associated with maintaining operation of the existing
groundwater contairunent and treatment system, implementation of additional institutional
controls, continued administrntion of institutional controls and site monitoring. Total
estimated costs for Alternative 2 assume that the action would only occur for a period of 30
years. Because the site would continue to be contaminated and pose risks to human health
and tbe environment indefInitely, actual costs and efforts associated with maintaining
Alternative 2 would be incurred indefInitely beyond the 30-year period.
Alternative 3: Soil Capping and Groundwater Containment and Treatment
ALTERNATIVE 3A:
. Surface capping of contaminated soils;
. Treatment of previously removed soils and a limited amount of excavated soils
using on-site incineration;
* Containment and treanIlent of groundwater and LNAPL;
. Treatment of oily wastes, sludges, equipment and debris; and
. Groundwater monitoring and institutional controls
Estimated present worth cost: $ 34,620,000 to $ 60,130,000
Implementation time: 2 years - soils
30+ years - groun':water, operations and maintenance
Under Alternative 3A, contaminated soils in the former wood-processing area and
along the historic drainage ditch (see Figure 17) would be capped to prevent direct human
contact and reduce infiltration of precipitation through the CODt:lminated soils. Contaminated
surface soil hot spots outside these areas would be excavated and consolidated with soils in
the process area prior to capping. The cap would cover an area of approximately 170,000
square feet. (A football fIeld is 57,600 square feet.) Approximately 213,000 cubic yards of
contaminated soils would remain in place under this alternative.
Soils previously excavated during EPA's 1985 removal action (bagged soils),
contaminated soils excavated during construction of groundwater remediation facilities (e.g.,
collection trenches), and contaminated soils located near Silver Bow Creek and down gradient
23
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MONTANA POLE ROD - DECISION Sly~L.\RY
..,
of the groundwater collection system would be treated in an on-site incinerator. The
-estimated volume of soil treated under this alternative is 23,000 cubic yards, which includes
approximately 10,000 cubic yards of previously removed soils plus approximately 13,000
cubic yards of excavated soils. Other soil actions which would be necessary under
Alternative 3A include filling excavated areas l sing treated soils, surface grading and
revegetation.
Under this alternative, oils and sludges currently in place at the site would be
in~inerated on-site along with soils. LNAPL recovered by the groundwater system while the
incinerator was operating would also be incinerated. LNAPL recovered after on-site
incineration has been discontinued would be incinerated off-site. Contaminated debris and
equipment would be decontaminated and disposed of in an appropriately licensed off-site
landfill.
A groundwater containment and treatment system would be constructed to contain the
LNAPL and dissolved groundwater contaminant plumes and capture the contamination before
it discharges to Silver Bow Creek. This system would include an extensive netWork of
extrnction and containment mechanisms (trenches, exrrnction wells, physical/hydraulic
barriers). Groundwater treatment above ground is assumed to consist of oil/water separation,
bioreactor treatment and carbon polishing. Other modes of treatment such as UV/oxidation
or granulated activated carbon (GAC) may be utilized instead of a bioreactor depending on
detailed design analysis and the ability to meet performance standards. Treatment of
contaminated groundwater would occur to the degree necessary to meet applicable
environmental standards and health-based criteria prior to discharge. Additionally, an in-sitU
(in-place) bioremediation process would be implemented to assist in long-term cleanup of
groundwater and subsurface soils.
Once site remediation bas effectively contained the contaminated groundwater and
LNAPL, and releases to Silver Bow Creek have been effectively reduced or eliminated, it is
expected that naturnl biodegradation and attenuation would effectively reduce the levels of
organic contaminants in Silver Bow Creek, stream sediments and groundwater downstream of
the site. These naturnl mechanisms would be relied upon to address the low level
contamination found in this area.
The specific design of the groundwater ~stem would take place during the remedial
. design and remedial action phase of site cleanup. The groundwater exrrnction and treatment
system could utilize the groundwater treatment plant constructed at the site by EP A.
Groundwater and LNAPL in and around the site would be monitored to evaluate the
effectiveness of the recovery and treatment system. The same institutional controls would be
~r; - ': ... implemented as those discussed under Alternative 2.
Total estimated costs for Alternative 3A assume the action would only occur for a
period of 30 years. Since the site would continue to be contaminated indefinitely, actual
costs and efforts as 30ciated with site monitoring, enforcement of institutional controls and
operation and maintenance of the cap and the groundwater system would be incurred
indefinitely beyond the 30 year period. ' . . ... -
24
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~[O~lA.""A POLE ROD - DECISIO~ S"l~Il\tl-\RY
ALTERNATIVE 3B:
. Surface capping;
* Treatment of previously removed soils and a limited amount of excavated soils
using biological land treatment;
Containment and treatment of groundwater and LNAPL;
.. Treannent of oily wastes, sludges, equipment and debris; and
* Groundwater monitoring and institUtional controls
Estimated present worth cost: $ 21,060,000 to $ 36,640,000
Implementation time: 3 years - soils
30 + years - groundwater, operations and maintenance
Alternative 3B is the same as Alternative 3A except that soils would be treated using
biological land treatment and all oils and sludges would be incinerated off-site. Biological
land treatment is not expected to achieve the degree of treatment provided by incineration;
however, fmal contaminant levels are anticipated to be within allowable levels. Design
stUdies would be utilized to determine achievable treannent efficiencies and identify any
additional remedial actions-which may be necessary in conjunction with biological land
treatment to ensure compliance with cleanup goals.
ALTERNATIVE 3C:
* Surface capping;
* Treatment of previously removed soils and a limited amount of excavated soils
using soil washing;
* Containment and treatment of groundwater and LNAPL;
* Treatment of oily wastes, sludges, equipment and debris; and
* Groundwater monitoring and institUtional controls
Estimated present worth cost: $ 27,720,000 to $ 43,780,000
Implementation time: 2 years - soils
30 + years - groundwater, operations and maintenance
Alternative 3C is the same as Alternative 3A except that soils would be treated using
soil washing and all oils and sludges would be dechlorinated and incinerated off-site.
Residual fine soils from the soil-washing process which do not meet cleanup criteria would
be further treated in a bioslurry reactor. The volume of residual fine soils requiring further
treattnent is estimated at five percent of the total volume of treated soils. As with biological
land treatment, soil washing is not expected to achieve the degree of treatment provided by
incineration; however, it is anticipated that allowable final contaminant levels will be met.
Design stUdies would be utilized to determine achievable treatment efficiencies and identify
any additional remuiial actions which may be necessary in conjunction with soil washing to
achieve cleanup goals.
25
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MONTANA POLE ROD - DECISION S'livLVIARY
Alternative 4: Partial Excavation and Treatment of Soils and Groundwater Containment
- and Treatment
AL TERNA TIVE 4A
* Excavation of contaminated surface and subsurface soils and treatmem using
on-site incineration;
* Treatment of previously removed soils using on-site incineration;
* Containment and treatment of groundwater and LNAPL;
* Treatment of oily wastes, sludges, equipment and debris; and
* Groundwater monitoring and institutional controls
Estimated present wonh cost: $ 77,880,000 to S 110,840,000
Implementation time: 5 years - soils
30+ years - groundwater, operations and maintenance
--
Under Alternative 4A, accessible contaminated soils in areas where surface soil
concentrations are above cleanup levels and wbere contamination above cleanup levels
extends from the surface to the groundwater table (see Figure 17) would be excavated and
treated using an on-site incinerator. The areas of the site which would be excavated under
Alternative 4A correspond to surface soil hot spots, the former process area, the waste water
discharge ditch and contaminated soils located near Silver Bow Creek and downgradient of
the groundwater collection system. Bagged soils previously excavated during EPA's 1985
removal action and contaminated soils excavated from construction of groundwater
remediation facilities (e.g., collection trenches) would also be treated in an on-site
incinerator. Excavation of surface soil hot spot areas would occur to a depth of
approximately three feet. Subsurface excavation would occur to a maximum depth of four
feet below the groundwater table. The esrim~tP.tt volume of soil excavated under this
alternative is 105,000 cubic yards. The estim:dPLi volume of soil treated under this
alternative is 115,000, cubic yards which includes the bagged soils. Other soil actions which
would be necessary under Alternative 4A include filling excavated areas using treated soils,
surface grading and revegetation.
Under Alternative 4A, approximately 124,000 cubic yards of cont~min~ted soils
would remain in place. This includes areas beacath the interstate highway which are
considered inaccessible and subsurface soils located outside of the former process and
drainage ditch areas which are contamin:ltHi by LNAPL near the groundwater table (see
Figure 13). These soils would be addressed through LNAPL extraction, soil flushing and in-
siru bioremediation.
Under this alternative, oils and sludges anrently in place at the site would be
incinerated on-site along with soils. LNAPL nx:overed by the groundwater system while the
incinerator was operating would also be incinemed. LNAPL ::covered after on-site'
incineration has been discontinued would be incinerated off-site. Contaminated debris and ..
equipment would be decODt~min~ted and disposed of in an appropriately licensed off-site
landfill.
26
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--
_&
:\'IONTAi~A POLE ROD - DECISIO:" Sl:~[vl-\RY
A groundwater containment and treatment syStem, similar to the Alternative 3 system.
would be constructed [0 contain the LNAPL and dissolved groundwater contaminant plumes
and captUre the contamination before i[ discharges [0 Silver P0w Creek. TILis system would
include an extensive netwC'fk of extraction and containment mechanisms (trenches, extraction
wells, physical/hydraulic barriers). Groundwater treatment above ground is assumed to
consist of oil/water separation, bioreactor treatment and carbon polishing. Other methods of
treatment such as UV/oxidation or granulated activated carbon (GAC) may be utilized instead
of a bioreactor depending on detailed design analysis and the ability to meet performance
standards. Treatment of contaminated groundwater would occur [0 the degree necessary to
meet applicable environmental standards and health-based criteria prior [0 dischnge.
Additionally, an in-situ bioremediation process would be implemented to assist in long-term
cleanup of groundwater and subsurface soils. Remediation of [he contaminated aquifer to
drinking water levels is a goal of this alternative.
Once site remediation has effectively contained the contaminated groundwater and
LNAPL, and releases to Silver Bow Creek have heen effectively reduced or eliminated, it is
expected that natural biodegradation and attenuation would effectively reduce the levels of
organic contaminants in Silver Bow Creek, stream sediments and groundwater downstream of
the site. These natural mechanisms would be relied upon to address the low level
contamination found in this area.
The specific design of the groundwater system would take place during the remedial
design and remedial action phase of site cleanup. Tbe groundwater extraction and treatment
system could utilize the groundwater system installed at tbe"site by EPA. Groundwater. and
LNAPL in and around the site would be monitored to evaluate the effectiveness of the
recovery and treatment system. The same institutional controls would be implemented as
those discussed under Alternative 2. Institutional controls may be adjusted or removed as the
remedial action progresses toward completion and site conditions allow.
Total estimated costs for Alternative 4A assumE" that the groundwater action would
only occur for a period of 30 years. Although groundwater aquifer remediation to cleanup
levels is a goal under this alternative, some source areas would remain and be treated in
place over the long term. Therefore, actual costs and efforts associated with site monitoring,
enforcement of institutional controls and operation and maintenance of the groundwater
system may be incurred beyond 30 years.
ALTERNATIVE 4B
... Excavation of contaminated surface and subsurface soils and treatment using
biological land treatment;
... Treatment of previously removed soils using biological land treatment;
... Containment and treatment of groundwater and LNAPL;
... Treatment of oily wastes, sludges, equipment and debris: and
. Groundwater monitoring and institutional controls
Estimated present worth cost: S 24,780,000 to $ 47,570,000
Implementation time: 6 years - soils
27
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:'¥IOl\lA...~A POLE ROD - DECISIO:\ St-:\l.\L\RY
JO-r- years - groundwater. operations and maintenance
Alternative 4B is the same as Alternative 4A except tllat soils would be treated using
biologicallanJ treatment JJ1d all oils and sludges would be incinerated off-site. Biological
land treatment is not expected to achieve the degree of treatment provided by incineration;
however, allowable fmal contaminant levels are anticipated to be met. Design studies would
be utilized to determine achievable treatment efficiencies and identify any additional remedial
actions which may be necessary in conjunction with biological land treatment.
..,
ALTERNATIVE 4C
'" Excavation of contaminated surface and subsurface soils and treatment using
soil washing;
'" Treatment of previously removed soils using soil washing;
... Containment and treatment of groundwater and LNAPL;
"'Treatment of oily wastes, sludges, ...quipment and debris; and
... Groundwater monitoring and institutional controls
Estimated present worth cost: $ 35,450,000 to $ 52,660,000
Implementation time: 3 years - soils
30 + years - groundwater, operations and maintenance
Alternative 4C is the same as Alternative 4A except that soils would be treated using
soil washing and all oils and sludges would be incinerated off-site. Residu'al flOe soils from
the soil washing process which do not meet cleanup criteria would be further treated in a
biosluIT)' reactor. The volume of residual fme soils requiring further treatment is estimated
at five percent of the total volume of treated soils. As with biological land treatment, soil
washing is not expected to achieve the degree of treatment provided by incineration;
however, it is anticipated that allowable fmal conL.aIIlin...Ilt kvels will be met. Design studies
would be utilized to determine achievable treatment efficiencies and identify any additional
remedial actions which may be necessary in conjunction with soil washing.
Alternative 5: Total Excavation and Treatment of Soils and Groundwater Containment
and Treatment
ALTERNATIVE 5A
... Excavation of all accessible contaminated soils and treatment with on-site
incineration;
... Treatment of previously removed soils using on-site incineration;
... Containment and treatment of groundwater and LNAPL;
... Treatment of oily wastes, sludges, equipment and debris; and
... Groundwater monitoring and institutional controls
Estimated present worth cost: $ 99,870,000 to $ 156,220,000
28
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...c.
:VI0~1A.'iA POLE ROD - DECISIO:\ Sl~[\L\RY
Implementation time:
8 years - soils
30~ years - groundw31er. operations :ll1d maintenanc~
under Alternative SA, all accessible contaminated site soils would be exclvated and
treated in an on-site incinerator. This includes the areas identified under Alternative 4 in
addition to subsurface soils impacted by LNAPL. These areas correspond to surface soil bot
spots, the fonner process area, the waste water discharge ditch and soil areas near the
groundwater table which have been impacted by LNAPL. Bagged soils previously excavated
during EPA's removal action would also be treated in an on-site incinerator. Excavation in
surface soil hot spot areas would occur to a depth 'of approximately three feet. Subsurface
excavation would occur to a depth of approximately four feet below the groundwater table.
Excavation of the soils impacted by the LNAPL is assumed to extend from tWo feet above to
four feet below the groundwater table. The estimated volume of soil excavated under this
alternative is 279,000 cubic yards which includes about 94,000 cubic yards of
uncontaminated soil requiring excavation to access underlying LNAPL-irnpacted soils. The
total estimated volume of soil treated under this alternative is 195,000 cubic yards and
includes the bagged soils. Other necessary activities would include filling excavated areas
using treated soils, surface grading and revegetation.
Under Alternative 5A, approximately 44,000 cubic yards of contaminated soils would
remain in place. This includes areas beneath the imerstate highway which are considered
inaccessible. These soJs would be addressed through LNAPL extraction, soil flushing and
in-situ bioremediation. . .
Under this alternative, oils and sludges currently in place at the site would be
incinerated on-site along with soils. LNAPL recovered by the groundwater system while tbe
incinerator was operating would also be incinerated.. LNAPL recovered after on-site
incineration has been discontinued would be incinerated off-site. Contaminated debris and
equipment would be decontaminated and disposed of in an appropriately licensed off-site
landfill.
A groundwater containment and treatment system would be constructed to contain the
dissolved groundwater contaminant plume and any residual LNAPL and capture the
contamination before it discharges to Silver Bow r:reek. However, the groundwater
containment and extraction design for Alternative 5A would entail a less extensive netWork of
extraction and containment mechanisms (trenches, extraction wells, pbysica1Jbydraulic
barriers) than under Alternatives 3 or 4 because excavation of all accessible source areas
containing LNAPL would occur as part of this alternative. Groundwater treatment above
ground is assumed to consist of oillwater separation, bioreactor treatment and carbon
polishing. Other methods of treatment such as UV/oxidation or granulated activated carbon
(GAC) may be utilized instead of a bioreactor depending 00 detailed design analysis.
Groundwater treatment above grouod would occur to the degree necessary to neet applicable
environmental standards and health-based criteria prior to discharge. Additionally, an in-sitU
bioremed.iation process would be implemented to assist in long-tenn cleanup of groundwater
and residual subsurface soil contamination. Remediation of the contaminated aquifer to
29
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MONT..\.'lA POLE ROD - DECISION SlTyL.\tL.\R.Y
-.
drinking water levels is a goal of this alternative.
Once site remediation has effectively contmd the contaminated groundwater and
LNAPL, and releases to Silver Bow Creek have be';:n effectively reduced or eliminated, it is
expected that natUral biodegradation and attenuation would effectively reduce the levels of
organic contaminants in Silver Bow Creek, stream sediments and groundwater downstream of
the site. These natUral mechanisms would be relied upon to address the low level
contamination found in this area.
The specific design of the groundwater system would take place during the remedial
design and remedial action phase of site cleanup. The groundwater extraction and treatment
system could utilize the groundwater treatment pIa:m installed at the site by EP A.
Groundwater and LNAPL in and around the site woold be monitored to evaluate the
effectiveness of the recovery and treatment system. The same institUtional controls would be
implemented as those discussed under Alternative 2. Institutional controls may be reduced or
lifted as the remedial action progresses toward completion.
Total estimated costs for Alternative 5A assume that the groundwater action would
occur for a period of 30 years. Although groundwater remediation to cleanup levels is
expected under this alternative, some inaccessible source areas (under the interstate highway)
would remain and be treated in place. Therefore, actual costs and efforts associated with site
monitoring, enforcement of institutional controls ami operation and maintenance of the
groundwater treatment system for the inaccessible source areas (under the interstate highway)
may be incurred beyond 30 years.
ALTERNATIVE 5B
* Excavation of all accessible contaminated soils and treatment using biological
land treatment;
* Treatment of previously removed soils using biological land treatment;
* Containment and treatment of groundwater and LNAPL;
* Treatment of oily wastes, sludges, equipment and debris; and
* Groundwater monitoring and institutional controls
Estimated present worth cost: $ 27,530,000 to $ 55).00,000
Implementation time: 11 years - soils .
30+ years - groundwi8:r, operations and maintenance
Alternative 5B is the same as Alternative SA except that soils would be treated using
biological land treatment and all oils and sludges wmIld be incinerated off-site. Biological
land treatment is not expected to achieve the degree of treatment provided by incineration;
however, it is anticipated that allowable fInal conrnmmant levels will be achieved. Design
stUdies would be utilized to determine achievable t:rcitD1ent efficiencies and identify any
additional remedial actions which may be necessary In conjunction with biologic.1l land
treatment.
30
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:\-10i'll.~~A POLE ROD - DECISIO~ S1..~[\L-\RY
ALTER..~ATIVE 5C
Excavation of all accessible contaminated soils and treatment using soil
washing;
... Treatment of previously removed soils using soil washing;
... Containment and treatment of groundwater and LNAPL;
... Treatment of oily wastes, sludges, equipment and debris; and
... Groundwater monitoring and institutional controls
Estimated present worth cost: $ 48,080,000 to $ 78,180,000
Implementation time: 4 year - soils
30 + years - groundw.ater, operations and maintenance
-
Alternative 5C is the same as Alternative 5A except that soils would be treated using
soil washing and all oils and sludges would be incinerated off-site. Residual fIne soils from
the soil washing process which do not meet cleanup criteria would be further treated in a
bioslurry reactor. The volume of residual fme soils requiring further treatment is estimated
at five percent of the total volume of treated soils. As with biological land treatment, soil
washing is not expected to achieve the degree of treatment provided by incineration;
however, it is anticipated that allowable fmal contaminant levels will be achieved. Design
studies would be utilized to determine achievable treatment efficiencies and identify any
additional remedial actions which may be necessary in conjunction with soil washing.
--
31
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...
. -.
:\10:\"T..\..'IA POLE ROD - DECISIO:\" SC\L\L-\RY
VIII. Sl~[\IARY OF CO:\IPARATIVE .-\..'iALYSIS OF .-\LTER'\.-\TIV~S
Section 300A30(e)(9) of the NCP requires that the agencies ~yaluate and compare the
remedial cleanup alternatives based on the nine :riteria listed below. Tbe first two criteria
overall protection of human health and the environment, and compliance with ARARs are
threshold criteria and must be met. The selected remedy must represent the best balance of
tht. selection criteria.
Evaluation and Comparison Criteria
Threshold Criteria
1.
Overall protection of human health and environment addresses whether or not a
remedy provides adequate protection and describes how potential risks posed through
each pathway are eliminated, reduced or controlled through treatment, engineering
controls or institutional controls.
2.
Compliance with applicable or relevant and appropriate requirements addresses
whether or not a remedy will comply with federal and state environmental laws
and/or provide grounds for invoking a waiver.
Primary Balancing Criteria
3.
Lon~-term effectiveness and permanence refers to the ability of a remedy to maintain
reliable protection of human health and the environment over time once cleanup goals
have been met.
4.
Reduction of toxicitv. mobility and volume through treatment refers to the degree that
the remedy reduces toxicity, mobility and volume of the contamination.
5.
Short-term effectiveness addresses the period of time needed to complete the remedy,
and any adverse impact on buman bealth and the environment tbat may be posed
during the construction and implementation period until cleanup goals are achieved.
6.
Implementability refers to the technical and administrative feasibility of a remedy,
including the availability of materials and services needed to carry out a particular
option.
7.
Cost evaluates the estimated capital costs, operation and maintenance costs and
present wortb costs of each alternative.
32
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~lOt-i!~~A POLE ROD - DECISI0~ SL~L\-L-illY
~lodifying Criteria
8.
State agency acceptance indicates whether, based on its review of the infonnation. the
state (MDHES) concurs with, opposes or has no comment on the preferred
:uernative. However, for this Site, :YIDHES is the lead management agency and EPA
is the suppon agency. As such, the State has identified the selected remedy and EP A
has concurred with and adopted that identification.
9.
CommunitY acceptance is based on whether community concerns are addressed by the
selected remedy and whether or not the community has a preference' for a remedy.
Although public comment is an important part of the fmal decision, MDHES and
EP A are compelled by law to balance community concerns with all of the other
criteria.
Following is a summary of the agencies' evaluation and comparison of alternatives.
Additional detail evaluating the alternatives is presented in the Feasibility Study repon.
1) Overall protection of public health and the environment: Alternatives 1 and 2 are not
expected to provide adequate protection of public health and the environment because
releases of and exposure to site contaminants remain uncontrolled. Alternatives 3A through
5C, if properly implemented, could be protective of public health and the environment.
However, the degree of protection provided by Alternatives 3A, 3B, and 3C is dependent
upon effective long term maintenance of the cap and the groundwater system. Alternatives
5A, 5B and 5C would provide the greatest degree of protection of public health and the
environment because all accessible conciminated source materials would be removed and
treated which substantially reduces potential risks from future releases.
2) Compliance with applicable or relevant and appropriate requirements (ARARs):
Alternatives 1 and 2 do not meet chemical-specific ARARs for groundwater or surface water.
Alternatives 3, 4 and 5 are expected to meet chemical-specific ARARs for surface water,
location-specific ARARs and action-specific ARARs. Achieving chemical-specific A.RARs
for groundwater is not likely under Alternative 3 because most source areas would remain in
place. Achieving chemical-specific ARARs in groundwater under Alternative 4 is uncenain
because, although a large volume of source material is removed, a substantial amount of
source material would remain in place and require long-term remediation. Achieving
chemical-specific ARARs for groundwater may be possible under Alternative 5 since all
accessible source areas are removed.
3) Long-term effectiveness and permanence: Alternatives I and 2 provide no long-term
effectiveness or permanence for reducing risks to human health and the environment beyond
those currently in existence at the site. Cleanup goals for the site would not be achieved.
33
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~IOl'rr..\;.'iA POLE ROD - DECISION SL~[\L\.RY
Alternatives 3, 4 and 5 permanently address the oils and sludges. contaminated equipment
and debris through treatment and off-site disposal.
Excavated soils are most effectively and permanently treated by incineration under
Alternatives 3A, 4A, and 5A. Biological land treatment and soil washing under Alternatives
3B, 3C, 4B, 4C, 5B, and 5C are not expected to be as effective as incineration but would
permanently reduce the levels of contamination to within established risk ranges. in-sitU
bioremediation would be effective at treating residual source and dissolved phase
groundwater contamination under Alternative 5. in-sitU bioremediation would be less
effective as applied to Alternatives 3 or 4 as substintial amounts of high strength source
material, not effectively treated by in-sitU bioremediation, would remain in place. Capping
under Alternative 3 is subject to deterioration over time and requires long term maintenance.
Containment and reliance upon engineering and institutional controls to protect human health
and the environment do not provide the degree of permanence that removal and treatment of
contamination does.
-...
Groundwater containment and treatment systems under Alternatives 3, 4 and 5 could all be
effective for containing contaminated groundwater, limiting contaminant migration, and
reducing impacts to Silver Bow Creek to allowable levels. Under Alternative 3 the
groundwater system is expected to require operation and maintenance indefInitely, since only
minimal soil excavation and treatment is planned. Under Alternative 4 the overall
effectiveness of groundwater remediation is expected to be greater than under Alternative 3,
because a large volume of contaminated soils and associated LNAPL is excavated and
treated. Operation and maintenance of the groundwater system under Alternative 4 is
expected to be required for a shoner period of time than under Alternative 3. Groundwater
treatment under Alternative 5 is anticipated to have the greatest effectiveness of the
alternatives because all accessible contaminated soils and LNAPL are excavated and treated.
Under Alternative 5, operation and maintenance of the groundwater system is expected to be
required for a shoner period of time than under either Alternative 3 or Alternative 4.
Because Alternative 5 captures and treats the grealest percentage of continuing sources of
contamination, Alternative 5 provides the greatest assurance of long-term effectiveness and
permanence. It is technically imprncticable to remove more source material than is
contemplated under Alternative 5.
4) Reduction of toxicity, mobility and volume: Alternatives 1 and 2 provide no reduction
of toxicity, mobility or volume through treatment beyond that provided by the actions
currently in place at the site. Alternatives 3, 4 and 5 reduce the toxicity and volume of oils
and sludges through either on-site incineration or off-site incineration. The toxicity of
contaminated equipment and debris is reduced by decontamination under Alternatives 3, 4
and 5.
The toxicity, mobility and volume of contaminan~ in excavated soils is effectively eliminated
34
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~IONTA.'lA POLE ROD - DECISION Sl.~L'\:L.\RY
by incineration under Alternatives 3A. .fA and SA. Biological land treatment and soil
washing under Alternatives 3B. 3C. 4B. 4C, SB and SC reduce the toxicity and volume of
contaminants in soils but not to the degree provided by in ~ineration.
Alternative 3 provides minimal reduction of toxicity, mobility and volume of contaminated
site soil because a cap is employed. Alternative 4 provides a greater reduction of toxicity,
mobility and volume of contaminated site soil than Alternative 3 because a large amount of
contaminated soils and associated LNAPL are excavated and treated. Alternative 5 provides
the greatest reduction of toxicity, mobility and volume of contamination in soils of all the
alternatives because all accessible contaminated soils and associated LNAPL are excavated
and treated.
Groundwater treatment systems included in Alternatives 3, 4 and 5, provide reduction of
toxicity, mobility, and volume of groundwater contamination. Alternative 4 provides greater
reduction of toxicity, mobility and volumt: of ~~undwater contamination than Alternative 3
because large sources of groundwater contamination (contaminated soils and LNAPL) are
excavated and treated. Alternative 5 provides the greatest reduction of toxicity, mobility and
volume of groundwater contamination of all the alternatives because all accessible sources of
groundwater contamination (contaminated soils and LNAPL) are excavated and treated.
S) Short-term effectiveness: Under Alternatives 1 and 2, there is potential for workers and
site visitors to be exposed to hazardous chemicals during implementation of the current
removal actions being performed by EP A at the site. Adhering to safe work practices and
using health and safety equipment is designed to limit the exposure to workers and visitors to
within allowable levels.
During implementation of Alternatives 3, 4 or 5 thef'" is ;Jotential for workers, site visitors,
and nearby residents to be exposed to hazardous chemicals. Adhering to safe work practices
and using health and safety equipment should limit the exposure to workers and visitors to
within allowable levels. Dust and vapor release control activities can be implemented to
limit this exposure potential. The incinerator used under Alternatives 3A, 4A, and 5A can
be designed to ensure emissions meet allowable standards. Given this and the shon duration
that the incinerator would be on-site, health risks to nearby residents would be low.
6) Implementability: Alternatives 1 through 5 are all technically implementable. . Capping
source areas (Alternative 3) is likely easier to implement than removal and treatment of
source areas (Alternative 4 and 5). Excavation of saturated soils is more difficult than
excavation of soils above the water table. For Alternatives 3, 4 and 5 the technologies for
soil and groundwater treatment are readily implementable and have all been l'~ed in full scale
application at other sites. Prior to full-scale implementation of any of these treatment
technologies at the site, design optimization studi.:s are appropriate. On-site incineration may
not be acceptable to the local community and off-site incineration can be difficult to
35
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~10NTA.'iA POLE ROD - DECISION Sl~L\l-\RY
implement because off-site incinerator operators are reluctant ro accept wastes containing
dioxin. Under Alternative 3, cap maintenance and operation and maintenance of the
groundwater system will have to continue indefInitely Operation and maintenance of the
groundwater systems under Alternatives 4 and .5 may be required beyond 30 years.
7) Cost: Alternative 1 is the least costly to implement. Alternative 5A is the most costly to
impkment. The 30-year present worth of Alternative 3 ranges from $16.5 million to $36.4
million; Alternative 4 ranges from $18.8 million to $88.6 million; and Alternative 5 ranges
from $22.5 million to $132.2 million.
Cost estimates provided for the FS showed above-ground biological treatment of soils to be
more cost effective than soil washing and incineration. Incineration is significantly more
expensive than either biological land treatment or soil washing. Design srudies could funher
define the relative costs of these treatment options.
Total estimated costs for all the alternatives assume that the action will only occur for a
period of 30 years. Under Alternatives 1, 2, and 3, since the site will continue to be
contaminated indefinitely, actual costs and efforts associated with remedial actions would be
incurred indefinitely beyond the 30 year period. Although the goal under Alternatives 4 and
5 is to remediate the si~e in a finite period of time, the actual costs and effons associated
with remedial actions, particularly groundwater remediation, may be incurred beyond the 30
year period. Additionally, because the estimated groundwater remediation costs under
Alternatives 3, 4 and 5 include entire system costs, utilization of the EPA groundwater
treatment system would reduce the estimated costs of groundwater remediation as presented
here and in the feasibility study repon.
8) State agency acceptance: The State of Montana has been the lead agency for the
development of this Record of Decision and bas selected a modified Alternative 5B as the
remedy contained herein. EP A has participated in the remedial process as the suppon
agency and has concurred with and adopted the Tr''11edy selection.
9) Community acceptance: Public comment on the Remedial Investigation, Feasibility
Study and Proposed Plan was solicited during fonnal public comment periods extending from
May 7, 1993 until July 7, 1993. Comments received from the community indicate
overwhelming suppon for the preferred remedy. Response to the community comments are
found in the Responsiveness Summary.
During the public comment period, MDHES and EPA received extensive comments from
Potentially Responsible Parties (pRPs) that have been identified for the Site. Comments
received from the PRPs indicated their opposition to the preferred alternative, specifically to
the goal of groundwater cleanup to drinking water Standards. In initial comments, the PRPs
preferred the approach of Alternative 3 which consists primarily of soil capping and stres~ed
36
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4 --
NIONT..\.~A POLE ROD - DECISIO~ Sl"\.L\L.\RY
that the most appropriate land uses at the site are industrial or recreational. In comments
received from some of the PRPs after the close of the comment period. the PRPs suggested
an approach based on a modification of Alternative 4B. PRP comments with ivIDHES and
EPA responses are also found in the Responsiveness Summary.
MDHES and EPA have carefully considered all comments, and have made some
modifications to the preferred remedy (Alternative 5B) which the agencies deem appropriate.
Modifications to preferred remedy are described in Section XI of this document.
~
..
37
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~IO~lA.,,"A POLE ROD - DECISIO;'; Sl~l\L\.RY
IX.
SELECTED RDIEDY
Based upon consideration of CERCLA requirements, the detailed analysis of alternatives. JJ1d
public cc mments, MDHES and EPA have determined that Alternative 5B. with some
modifications, represents the best balance of considerations using the selection criteria and IS
the appropriate remedy for the site. This alternative will provide maximum source
reduction, remediate groundwater to the extent practicable and limit releases to Silver Bow
Creek to allowable levels. All accessible contaminated soils and LNAPL will be excavated
to the extent practicable and treated, preventing this material from continuing to contaminate
groundwater. The long-term effectiveness and degree of permanence of the selected remedy
is high. MDHES does not expect any unmanageable short-term risks associated with this
alternative. This remedy will comply with all applicable or relevant and appropriate
requirements. This remedy uses treatment technologies and permanent solutions to the
maximum extent practicable and will be cost effective. The selected remedy will also satisfy
the preference for treatment as a principal element of the remedy and for on-site remedies
established in CERCLA. While certain other alternatives may better satisfy certain
individual selection criteria, the selected remedy best meets the entire range of the selection
criteria cmd achieves, in the determination of both EP A and MDHES, the appropriate
balance, considering site specific conditions and the criteria identified in CERCLA and the
NCP. The criteria described above are discussed in more detail in Section X, Statutory
Determinations, below.
Components of Selected Remedv
The major components of the selected remedy include:
1.
Excavation of contaminated soils from accessible areas of the site, to the
extent practicable. The volume of soils is estimated to be approximately
208,000 cubic yards;
2.
Treatment of excavated soils (208,000 cubic yards approximately) and
previously removed soils (10,000 cubic yards approximately) by above ground
biological treatment;
3.
In-place biological treatment of contaminated soils below tbe depth of
excavation before backfilling;
4.
Backfill of excavated and treated ~oils into excavated areas if possible. surface
grading and revegetation;
5.
Soil flushing of inaccessible soils areas (principally underlying Interst1te
15/90) in oider to recover hazardous substances;
38
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6.
.. --
~lONTA.~A POLE ROD - DEClSIO:--; S"l~[vl-\RY
Containment of contaminated groundwater and L~APL using physic:li and/or
hydraulic barriers (as determined during remedial design) in order to prevent
the spread of contaminated groundwater and L ~APL and to limit releases of
contamination into Silver Bow Creek:
7.
Treatment of extracted groundwater using the present EPA water treatment
plant (which consists of oil/water separation followed by granulated activated
carbon treatment). The ultimate design of the groundwater treatment system
(as determined during remedial design) may include the addition of biological
means or ultraviolet oxidation (UV /oxidation) to maximize cost effectiveness
of the treatment system. Treatment will meet standards for discharge or
reinjection, as appropriate;
8.
Discharge of extracted, treated groundwater into Silver Bow Creek and/or
reinjection of extracted, treated groundwater into the aquifer (as determined
during remedial design);
9.
Enhanced in-siru biological treatment of contaminated groundwater,
inaccessible contaminated soils areas and contaminated soils not recovered by
excavation;
10.
Treatment of contaminated site debris and equipment by decontamination
followed by disposal of these materials in a licensed off-site landfill;
11.
Treatment of contaminated oils and sludges in a licensed off-site incinerator;
12.
Additional institutional controls preventing access to contaminated soils and
groundwater; and
13.
Groundwater monitoring to determine movement of contaminants and
compliance with remedial action ~.quirements.
Once site remediation has effectively contained the contaminated groundwater and LNAPL,
and releases to Silver Bow Creek have been effectively reduced or eliminated, it is expected
that natural biodegradati.on and anenuation will effectively reduce the levels of organic
contaminants in Silver Bow Creek, stream sediments and groundwate!" downstream of the
site. These natUral mechanisms will be relied upon to address the low level contamination
found in this area.
Estimated Costs of the Remedv
The total present worth sost of Alternative 5B was estimated by ARCO in the feasibility
39
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:\tl0l'il~'i'A POLE ROD - DECISIOl" SL~[\L\RY
study in the range of S27.5 million to S55.2 million. These costs are detailed in T:lble ~ 1.
The estimated cost of the selected remedy is expected to varj somewhat from that of
Alternative 5B as explaiP~d below.
Cost {Jocertainties
The actual cost of implementing the remedy will be lower than the Alternative 5B estimate
because the groundwater treatment plant constructed by EPA will be utilized. Additionally,
ARCa did not fully account for soil flushing costs in the FS. ARCa has provided those
costs to DHES as shown in Table 22. The estimated 30 year present worth cost for soil
flushing under the interstate highway ranges from $328,000 to $612,000. Subtracting the
cost of the treatment facility, estimated between $981,000 and $1,090,000, from the original
cost estimate and adding the cost of soil flushing changes the total present worth cost of the
alternative to between $26.9 million to $54.7 niillion.
"'!.
Furthennore, the agencies believe that the estimate of costs for this alternative as presented
by ARCO in the feasibility study report significantly overstate certain cost elements. For
example, the cost figure of $17.00 per yd3 for excavation of soils can be expected to apply
only to a portion of the most difficult to excavate materials. The costs for most of the
excavation should be under $9.00/yd3. For purposes of comparison of alternatives, however,
even the higher figure for this alternative is used. For purposes of budgeting and planning,
the agencies' best estiInate of the cost of this alternative is $26.9 million. .
It is also recognized that operation and maintenance costs beyond the thirty year time frame
used in the FS, and the discount rate used to evaluate the present worth of operation and
maintenance costs are important considerations. DHE~ recognizes that tbe use of a 7 percent
discount rate used in the FS and calculation of present wortb costs without inclusion of
inflation, tends to underestimate future costs. This also makes the costs of remedies that rely
more heavily on future actions such as operations and maintenance for the bulk of site
remediation appear less costly than capital intensive remedies.
D:EffiS f1IlIlly believes that, because Alternative 5 removes and treats a large volume of
source material while Alternative 3 does not, total remediation time under Alternative 5 is
substantially less tban under Alternative 3. Therefore, DHES believes the costs of
Alternative 5 beyond 30 years would be less than the costs of Alternative 3 beyond 30 years.
Some elements of the remedy will be further refined during remedial design. Specific design
and start-up testing will be necessary prior to implementation of the selected n'~edy.
Cleanup Levels
Currently the Montana Pole site is zoned for industrial land use with residential use allowed
40
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\-lONTf\.~A POLE ROD - DECISIOI' Sl~LVL\.RY
for owners and caretakers of businesses on the premises. However, it is possible that the site
will be restricted from any residemial use in the future. The PRPs indicated in comments
surmined during the Proposed Plan commem period that they are pursuing rezoning of this
area, as well as creation of conservation easements and possibly other institUtional controls to
preclude residential land use arid groundwater use at the site. Representatives of the
Planning Office of Bune-Silver Bow County have expressed a willingness to accommodate
the PRPs' requests and institute such land use restrictions.
Accordingly, cleanup levels and the selection of the remedy are based upon an assumption of
adequate institutional controls to prevent any residential use at the site. Soil cleanup levels
have been developed to protect recreational and industrial land users at the site from
excessive health risks. If, for any reason, appropriate land restrictions are not acrually
implemented, cleanup goals will be adjusted accordingly.
Cleanup levels for site soils are listed in Table 23. These levels are based on a I in
1,000,000 cancer risk level for recreational land use at the site for each contaminant of
concern for the most susceptible exposure pathway. For example, the cleanup level for PCP
corresponds to a 10-6 risk level via dermal exposure, while the cleanup level for dioxins)s
based on a 10-6 risk level via ingestion. These cleanup levels correspond to total cancer risk
of approximately 3.86 x 10-0 when risks for all contaminants of concern and all pathways are
summed (see Table 24). These cleanup levels have been set using the 10-6 target to be
protective. These cleanup levels correspond to a total cancer risk of approximately 2.0 x 10'~
for industrial land use as shown on Table 24.
The cleanup goals for site groundwater are shown on Table 25 and include maximum
contaminant levels (MCLs) and non-zero maximum contaminant level goals (MCLGs). For
those contaminantS of concern for which MCLs or MCLGs do not exist, cleanup levels will
be based on a 1 in 1,000,000 cancer risk level or a 0.9 hazard index for ingestion of
groundwater. Cleanup goals for groundwater must be met at the Point of Compliance, which
will be the management unit boundary, as defmed below. These cleanup goals are necessary
even with planned institutional controls to ensure the contamination does not spread, Silver
Bow Creek is protected, and the NCP expectations for groundwater are met.
The cleanup levels for Silver Bow Creek are shown in Table 26 and are based on MCLs,
non-zero MCLGs and the Montana Water Quality Act I-Classification standard. One goal of
the groundwater remedial action is to contain and then remediate contaminated groundwater
in order to limit release of contaminants to Silver Bow Creek and reduce contaminant levels
in the creek to within applicable standards. Using the I-Class methodology, instream
contaminant concent::ltions at the Point of Compliance must be reduced to the larger of either
Gold Book levels or one-half of the mean instream concentrations immediately upstream of
the site. TIlls takes into account that there may be other sources of contaminants upstream of
the site. However. as all sources of contaminants are reduced or eliminated, instream
41
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~10NTA,~A POLE ROD - DECISION St~L\'L\RY
contaminant levels from Montana Pole sources will approach the Gold Book levels.
Therefore the ultimate cleanup levels which are to be achieved in the stream are Gold Book
levels, MCLs and non-zero MCLGs as shown on Table 26.
The cleanup levels for treated water discharges to Silver Bow Creek are also based on
MCLs, non-zero MCLGs and the I-Classification standard. The ultimate cleanup levels
which are to be achieved are shown on Table 27.
The cleanup levels for any water to be reinjected into the aquifer are based on non-
degradation criteria and must be no greater than the average concentration of groundwater
contamination in the area of recharge.
Points of ComDliance
--:
Compliance with cleanup levels described in Table 23 must be met for all excavated soils.
Other perfonnance standards must be achieved for contaminated soils below the depth of
excavation or for soils not accessible to excavation (under the EP A water treatment plant and
under Interstate 1-15/90).
For groundwater, compliance with remediation levels must be achieved at the waste
management area boundary. Since the contaminated materials will be excavated, treated to
levels protective for soil standards, and returned to their place, some contaminated material
will effectively remain in place. In such a situation, EPA has determined that "the
remediation levels should generally be attained at and beyond the edge of the waste
management area." Preamble to the fInal NCP, 55 Fed. Reg. 8753 (March 8, 1990). This
boundary can effectively be defmed as the edge of the excavated area, including any
additional area where contaminated material is not excavated for any reason. This boundary
is to be specifically delineated during remedial design/remedial action to ensure that
groundwater contamination does not migrate into uncontaminated areas. Along Silver Bow
Creek, this boundary is to be the south bank of the creek. Using this boundary as the point
of compliance for attainment of the groundwater remediation levels is protective of any off-
site groundwater uses and protective of the water quality goals for the stream.
This point of compliance reflects the change from the Proposed Plan that results from
elimination of tbe possibility of future residential use at the site. Because impending zoning
changes and other institutional controls will prevent use of groundwater on the site for
drinking water purposes, it will not be necessary to attain the remediation levels throughout
the contaminated plume itself, as anticipated in the Proposed Plan. IT, however. appropriate
changes and cor-troIs are not implemented, tbe point of compliance should be viewed as
throughout the plume, except tbe area under the iP'~rstate, since any other location on the
site would be a potential area for access to groundwater for drinking water purposes.
..2
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yl0~"T~~A POLE ROD - DECISION S"l-:\l\L-\RY
Surface water cleanup levels must be achieved at all pointS within Silver Bow Creek.
upstream surface water measurements. needed for determination of the I-Class standa.rd.
must be made upstream of all sources of contamination at the site. Additionally. any runoff
from the site to Silver Bow Creek, for example, from precipitation or snow melt, must me~t
the same surface water standards identified for t;eated water discharge. Runoff not meeting
those standards must be captured and treated along with extracted groundwater prior to
discharge.
Perfonnance Standards for Soils
For soils and sediments, the remedial goal is treatment 50 that the contaminant concentration
levels pose DO unacceptable risk to human health or the environment. Since no federal or
state chemical specific ARARs exist for these media, cleanup levels were determined for
contaminants of concern through a site specific risk assessment.
The specific performance standards which will be used to ensure attainment of the
remediation levels for these contaminated media are:
...,
o
Excavation of accessible soils and associated LNAPLs with contamination
levels in excess of the cleanup levels specified in Table 23. Depth of
excav.ation, panicularly at and below the groundwater table, will be based on
field judgment and technical practicability, as determined by the lead agency in
consultation with the support agency. LNAPLs at tbe groundwater table will
be recovered to the maximum extent practicable as determined by the agencies;
o
Soils below the depth of excavation with contaminant levels above cleanup
levels specified in Table 23 will be bioremediated in place. Biotreatment may
include nutrient addition via irrigation, and tilling on routine intervals. After
it has been determined by the lead agency, in consultation with the 5Uppon
agency, that in-place bioremediation of these soils is no longer effective or
practicable and contaminant levels have plateaued, or it is determined by the
agencies that these areas would be effectively addressed by the in-siru
bioremediation implemented under the groundwater actions, these areas will be
backfilled. Residual contamination will be further treated by in-siru
bioremediati~n as outlined under Performance Standards for Groundwater;
o
Treatment of excavated and previously excavated soils to achieve cleanup
levels specified in Table 23. Soils excavated from neaf Silver Bow Creek
whicli contain tailings materials with elevated metals concentrations will be
biologically treated and disposed in an appropriate Bune mine waste
repository. All contaminated soils north of the active railroad bed are
considered tailings material;
43
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-.
'.. -.,.
:\:I01'iTA.,\;A POLE ROD - DECISIO~ Sl~[\'L-\RY
~
Backfill af treated soils intO excavated JIeas if possible. filling of remlining
excavations with clean fill. replacemem of all clean soils. surface grading and
revegetation or covering with suitahle material .:ampatible with existing or
futUre land .lses;
o
Remediation of inaccessible contaminated soils (consisting primarily of those
soils underlying Interstate 1-15/90 and any soils under the EPA water treatment
plant) by a tWo phased approach. First, enhanced LNAPL recovery via
extraction wells and recovery trenches using hydraulic gradients and soil
flushing to remove hazardous substa:nces from these inaccessible soils.
Adjustment of pH, use of surfactants and other methods should be considered
to maximize recovery of hazardous substances. After it has been determined
by the lead agency> in consultation with the support agency, that recovery of
hazardous substances from these areas by these methods is no longer effective
or practical and contaminant levels :..1ve plateaued, these areas will be
addressed by in-sitU bioremediation as outlined under Perfonnance Standards
for Groundwater;
o
Implementation of engineering and institUtional controls during the remedial
action to prevent access to contamination and to limit the spread of
contamination; and
o
Attainment of all ARARs identified in Appendix A for the remediation of
soils.
Sampling will be performed during the response acrion to verify that all soils contaminated
above the cleanup levels are treated. The samplirig proor.wi shall be developed during
remedial design.
Performance Standards for Groundwater
For site groundwater, remediation goals provide maximum source reduction and protect
Silver Bow Creek and uncontaminated groundwater by minimi7ing migration of contaminants
with the groundwater. Cleanup levels for groundwater are MCLs and non-zero MCLGs
established by the Safe Drinking Water Act or risk based levels developed in the absence of
MCLs or MCLGs. Attainment of these cleanup levels at groundwater points of compliance
will be protective of human health and the environment and will ensure that uncontaminated
aquifers and adjacent surface waters are protected for potential beneficial uses.
The specific performance standards which will be used to ensure attainment of the
remediation goals for groundwater are:
44
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-
yIO~l..\.~A POLE ROD - DECISIO~ SC\L\L\.RY
:)
Containment of contaminated groundwater and L~.-\PL using hydraulic and:or
physical barriers (as detennineD during remedial design) ro effectively prevenr
the spread of contaminated groundwater and LNAPL and limit releases of
contamination inro Silver Bow Creek. Releases into Silver Bow Creek must
be reDuceD in order to achieve cleanup levels identifieD in Table 26 for Silver
Bow Creek. Migration of contaminateD groundwater must be limiteD in order
to maintain groundwater cleanup levels (Table 25) at groundwater points of
compliance;
o
Treatment of extracteD groundwater to cleanup levels in Table 2; prior to
discharge to Silver Bow Creek. Control and treatment, if necessary, of any
contaminateD runoff prior to discharge to Silver Bow Creek to meet the same
cleanup levels; .
o
Treatment of the contaminated groundwater aquifer and contaminateD soils not
recovered by excavation by enhanceD in-sicu biormeDiation. in-situ treatment
may include the reinjection of treateD groundwater and the addition of oxygen
and nutrients to promote the biodegradation of contaminants. in-sicu treatment
of the site groundwater will continue until contaminant levels have plateaued
and it is no longer effective or practical to continue treatment, as detennined
by the le.ld agency in conjunction with the support agency;
o
Attainment of all ARARs identifieD in Appendix A for groundwater
remediation;
o
Monitoring of groundwater wells within or proximate to the contaminated
groundwater plume for contaminants of concern for groundwater; and
o
Implementation of institutional controls to prevent access to or impacts upon
contaminateD groundwater at the site.
Groundwater sampling will be performeD during the response action to verify that
contaminateD groundwater above the cleanup levels is containeD and treateD. It is anticipated
that the treatment prescribeD for sources of contamination at the site will effectively reduce
the levels of contamination and shrink the contaminant plume sufficient to stabilize the site
within a reasonable period of time.
ComDliance SamDlinl! Prol!T3m
A sampling program for monitoring the remedial action and delermining compliance with the
performance standards shall be implemented during the remedial action. In addition. to
ensure that groundwater performance standards are maintained. it is expected that
~5
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ylO='iTA.~A POLE ROD - DECI5IO:-'; SL~[\'LillY
groundwater will be monitored at least twice annually during the groundwater seasonal high
aPd low for a period of at least three years foUowing discontinuation of groundwater
remediation. These monitOring programs will be developed during remedial design and shill
include, at a minimum, the following: analytical parameters (focusing on the contaminants
of concern, but analyzing other contaminants, if any, that are not contaminants of concern
and are determined to be occuning at levels exceeding MCLs or non-zero MCLGs),
sampling points, sampling frequency and duration, and statistical methods for evaluating
data. Specific performance monitoring points shall be specified and approved by EP A and
MDHES during remedial design, considering appropriate points of compliance.
Because the soils cleanup levels established in this Record of Decision are health based
standards for recreational use of the Site that do not provide for unlimited use with
unrestricted exposure, and because residual hazardous substances may be left on-site and the
cleanup is expected to take several years, the selected remedy will require five year reviews
under Section 121(c) of CERCLA, Section 300.430(f)(4)(ii) of the NCP, and applicable
guidance to assure the long-tenn effectiveness of the remedy.
As there are residents and businesses utilizing groundwater for domestic and lawn watering
purposes in the immediate vicinity of the site, all wells within one-quaner mile of
contaminated site groundwater will be sampled on a routine basis for contaminants. If site
related contaminants are detected in any well above regulatory or risk based levels,
appropriate measures such as individual treatment at the tap shall be implemented as deemed
appropriate by the regulatory agencies.
En2ineenn2 and Institutional Controls
These controls are required to maintain the protectiveness of the remedy. Since cleanup for
all media are not likely to be met in less than 10 years, measures must be institUted to
control risks during implementation of the remedy. Fencing and posting of areas where
active remediation is oecuning will be required to prevent unauthorized access to
contaminated media or to remedial action areas. The remedy itself includes certain actions to
contain and prevent migration of the contaminant plume during implementation of the
remedy. The design of this engineered containment will have to consider and accommodate
removal actions to be conducted at the Lower Area One Operable Unit of the Silver Bow
CreeklButte Area NFL Site, panicularly compensating for any dewatering in connection with
the removal of mine railings at that site.
The institutional controls which must be implemented for the selected remedy include
adequate zoning restrictions, conservation easemems, and otber controls to prevrnt any futUre
residential use of the site and appropriate controls to prevent any water well drilling in the
contaminated groundwater plume and adjacent areas to prevent additional receptors of
contaminated groundwater or an expansion of the plume. As noted above, the PRP's for the
~6
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"10~lA.;'i"A POLE ROD - DEClSIO:\" SC\[\l-illY
site have indicated that they are currently pursuing implementation of these '.::ontrols. in
coordination with the city/county government. If controls deemed adequate by the agencies
are not ultimately implemented, the assumptions used in determining the points of
compliance aIld other aspects of the selected remedy will be invalid. and the contingency
measures specified below will be implementoo.
Contin!!encv Measures
Soil Remediation
Soil cleanup levels have been determined based on the anticipated implementation of zoning
restrictions, conservation easements and groundwater restrictions by the PRPs and Butte-
Silver Bow County which will permanently prohibit residential and groundwater use at the
site. If these permanent site-wide changes are not implemented, revised soil cleanup levels
based on residential land use will be substituted for the recreational land-use cleanup levels
presented in this Record of Decision.
If the residence which currently exists on-site remains after implementation of the
institutional controls, contaminated soils subject to residential use will be removed and
replaced with clean soils. Soil removal levels will correspond to a 1 in 1,000,000 cancer
risk level for residential land use for each contaminant of concern for the most susceptible
, exposure pathway. '
Groundwater Remediation
Groundwater remediation points of compliance are based on the expected implementation of
zoning restrictions, conservation easements, and groundwater restrictions by the PRPs and
Bune-Silver Bow County. If these permanent changes are not implemented, the groundwater
points of compliance will be revised to require compliance with remediation levels
throughout the contaminated groundwater plume.
Oils and Sludges Remediation
The selected remedy for oils and sludges is off-site incineration. Investigation during the
feasibility study detennined that some licensed incinerators are reluctant to accept wastes
containing dioxin. If, subsequent to the implementation of the selected remedy, no facility is
available or willing to accept the site oils and sludges for incineration, the lead agency will
require the implementation of a contingency plan. Such a contingency plan would consist of:
o
A determination by the agencies that no facility is available or willing to
accept these wastes for treatment and that no facility is likely to become
available in the future;
~7
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4 -.
:VIO~T..\.~A POLE ROD - DECISIO;\; SC\,[\LillY
~
'-
All practical methods for off-site treatment, disposal. reuse and recycling will
be investigated. and. if an appropriate option of this rype is available. this
option will be substituted for the selected remedy: otherwise.
o
Oils and sludges will be treated usi..,g on-site incineration which will comply
with all ARARs.
The decisions to invoke any or all of these contingency measures may be made by the
agencies at any time during implementation of the remedial action, as appropriate.
.+8
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MONTAt~A POLE ROD - DECISION Sl,-:\-LVL.\RY
STA TrTORY DETERvDNA nONS
x.
While the majority of the comments received from the communiry supported selection of
Alternative 5B, many of the comments submitted, panicularly those submitted by the PRPs,
suggeste I use of a containment remedy rather than removal of the source of contamination.
However, after considering those comments fully, as evidenced in the Responsiveness
Summary, the agencies have detennined that maximum removal of the source, as outlined in
the remedy description, is the appropriate remedy for the site and most fully satisfies the
selection criteria established in CERCLA and the NCP.
...
-.
A number of site specific conditions have been considered by the agencies in the
determination of the remedy. Much of the contamination at the site exists in the form of a
light non-aqueous phase . liquid (LNAPL) which floating on the groundwater surface at a
depth that ranges from -approximately 5 to 20 feet below ground surface. No dense non-
aqueous phase liquid (DNAPL) was found at the site. Since the LNAPL material is lighter
than water, the groundwater essentially fOnTIS a floor which stops the downward migration of
the LNAPL. This material floating on top of the groundwater then constitutes a major
source of contamination to the groundwater and Silver Bow Creek by dissolving into the
groundwater. This dissolved phase of contamination then migrates with the natural
groundwater movement and spreads to surrounding areas and enters the stream.
With a substantial amount of high-strength source material in contact with site groundwater,
a containment remedy may have to operate essentially forever in order to prevem releases of
contaminants to the stream and surrounding areas. Certain elementS of the selected remedy
are intended to eliminate this continuing source of contamination. After elimination of this
source material, residual contamination levels will be further reduced using long-term in-sitU
biological degradation. This may ultimately allow a stabilization of site conditions such that
containment at the site may no longer be necessary.
Both DHES and EP A have determined that, considering all appropriate factors, including site
specific conditions and the remedy selection criteria specified in CERCLA and the NCP, the
remedy presented in this record of decision, including excavation and/or treatment of the
contaminated source material, both soils and LNAPL, is the appropriate remedy for the site.
Under CERCLA section 121, MDHES and EPA must select a remedy that is protective of
human health and the environment, complies with applicable or relevant and appropriate
requirementS (unless a statUtory waiver is justified), is cost-effective, and utilizes permanent
solutions and alternative treatment technologies or resource recovery technologies to the
maximum extf;nt practicable. In addition, CERCLA includes a preference for remedies that
include treatment which permanently and significantly reduces the volume, toxicity, or
mobility of hazardous wastes as a principal element. The following sections discuss how the
selected remedy meetS these statutory requirements.
.1.9
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.. -.
MOI'l"TAl"JA POLE ROD - DECISION S"L~[\L~Y
Protection of Human Health and the Environment
The selected remedy protects human health and the environment first through containmem
and then treatment of contaminants at the site, including a combination of soil and
groundwater remedial actions and use of institUtional controls. Soil actions include
excavation and biological treatment of the LNAPL plume and contaminated soils. Treated
soils will be backfilled into excavated areas and revegetated.
::l
Soil flushing and in siru biological treatment will be used in those areas where excavation is
not practicable or cost effective, as defined in the remedy description section.
Implementation of the soil flushing alternative under 1-15/90 will eliminate the need for
relocation/excavation of the Interstate Highway and will reduce the levels of contamination in
those areas to the extent practicable. The other soils treatment alternatives evaluated were
not implementable for the contaminated soils under 1-15/90 without removing the roadbed.
Prior to backfilling of excavated areas, in place biological treatment of contaminated soils
below the depth of excavation will reduce the volume and toxicity of these materials and aid
in groundwater control.
Biological treatment of the contaminated soil will reduce the threat of exposure through direct
. contact with or ingestion of contaminated soil. By excavating the contaminated soils and
treating them, the cancer risks from exposure will be reduced to approximately 3.9 x lQ-6 for
recreational use which is within the EPA's acceptable risk range of 1 x 10"' to 1 x 10-0 as
specified by the NCP. In addition, the cleanup levels established will be protective for
industrial use at the site at an excess cancer risk of approximately 2 x lO's. It is anticipated
that residential use at the site will be prohibited through the use of institutional controls.
There are no short term threats associated with the selected remedy that cannot be readily
controlled. In addition, no adverse cross-media impacts are expected from the remedy.
Initially, containment of contaminated groundwater will reduce the potential for exposure to
contaminants in adjacent aquifers and in Silver Bow Creek. Penn anent protectiveness will be
attained through removal and treatment of contaminant source areas and then treatment of the
groundwater, with treatment and discharge or reinjection of extracted groundwater and in sitU
biological treatment of gMundwater.
By first containing releases to surface water and then removing sources and remediating the
groundwater migrating to Silver Bow Creek, protection of affected surface waters will be
achieved. Also by treating extracted groundwater to drinking water standards before
discharging to surface water, the loading of contaminants of concern from this site will be
brought to within acceptable levels for Silver Bow Creek. Once all these sources of
contamination from the site are addressed, natural attenuation and biodegradation will restOre
the stream to acceptable and protective levels for contaminants of concern from this site.
50
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MONT~'
A POLE ROD - DECISION SLyL\-L~Y
There are no short tenn threats associated with the selected remedy that cannot be readily
controlled. In addition, no adverse cross media impacts are expected from the remedy.
A variety of engineering and institUtional controls will be UriJlemented with the remedy to
ensure protectiveness whi1e the remedy is being implemented and in' the futUre. As there are
residents and businesses utilizing groundwater for domestic and lawn watering pUIposes in
the immediate vicinity of the site, all wells within one-quarter mile of contaminated site
groundwater will be sampled on a routine basis for contaminants. If site related
contaminants are detected in any' well above regulatory or risk based levels, appropriate
measures such as individual treatment at the tap shall be implemented as deemed appropriate
by the regulatory agencies. institUtional controls will be implemented to prohibit
groundwater use in the affected area and to prevent an expansion of the plume. Fencing and
posting to prevent unauthorized access to contaminated media during remediation will be
used.
Comoliance with Aoolicable or Relevant and 1\ porooriate Reauirements
The fmal detennination of ARARs by MDHES and EP A is set forth in Appendix A attached
to this Record of Decision. The selected remedy will comply with all applicable or relevant
and appropriate requirementS (ARARs). No waiver of ARARs is expected to be necessary.
Some significant ARARs are listed below.
Contaminant-specific ARARs
Contaminant-specific ARARs typically set levels or concentrations of chemicals that may be
allowed in or discharged to the environment. The primary contaminant-specific ARARs for
this remedy are the maximum contaminant levels (MCLs) and non-zero maximum
contaminant level goals (MCLGs) established ur.der &~ SC'.fe Drinking Water Act. The
selected remedy will remediate existing groundwater contamination to achieve these relevant
and appropriate MCLs and MCLGs at appropriate points of compliance.
In addition the remedy will attain the surface water quality standards for site contaminants in
Silver Bow Creek, as designated under Montana law. ARM 16.20.623 specifies the
standards for the "1" classification, applicable to Silver Bow Creek, and requires evenrual
attainment of Ambient Water Quality Criteria (Gold Book levels).
Since no treatment standards have been set for the RCRA listed wastes on site (F032 and
F034 wastes) as of the date of this Record of Decision, RCRA Land Disposal Restrictions
will not apply to the remedy.
51
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~10NTAl'lA POLE ROD - DECISIO~ S'L~L\L\.RY
Location-specific A.RARs
wcation-specific ARARs establish requirements or limitations based on the physical or
geographic setting of the Site or the existence of protected resources on the Site.
Portions of the site are within a lOO-year floodplain. Design of the remedy will have to
ensure that no prohibited structures or other artificial obstructions are constructed in the
floodplain. Although treated soils will be backfilled into excavated areas within the
floodplain, the floodplain may not be used for storage or disposal of wastes.
~.
Regulations concerning the protection of wetlands, including those relating to the Fish and
Wildlife Coordination Act and Executive Orders 11,988 and 11,990, will apply to the
implementation of this remedy. The protected resource which has the potential to be
adversely affected by the selected remedy is wetland areas directly associated with Silver
Bow Creek. These wetland areas are also within the Lower Area One Operable Unit of the
Butte-Silver Bow Creek NPL site and are being addressed under removal actions taking place
within LAO. Consultation with the U.S. Fish and Wildlife Service during the design and
implementation phase will be required to establish if any additional mitigative measures,
beyond those planned for LAO, will be necessary.
Similarly, the one protected historical resource near the site is a slag wall that is actually
located on the Lower Area One Operable Unit. Any necessary mitigation measures or other
protection for that slag wall are being determined in connection with activities at LAO.
Action-specific ARABs
Action-specific ARARs generally provide guidelines for the manner in which specific
activities must be implemented. Thus, compliance with many action-specJic requirements
must be ensured through appropriate design of the remedy.
The remedy will meet all action-specific ARARs, including the following RCRA
requirements: monitoring for releases from waste management units, requirements for
management of waste piles and land treatment units, and transponation requirements, as well
as all requirements for reclamation of excavated areas.
In addition, the remedy, as designed, will meet other action-specific standards, including
Clean Air Act regulations for particulate maner, dust control practices that achieve ambient
air quality standards, Clean Water Act regulations requiring run-on and run-off controls that
prevent any discharg:. of contaminants from remecUal actions that would violate surface water
standards, sufficient treatment before reinjection of groundwater to ensure compliance with
groundwater nondegradation standards, the requirements of the Underground Injection
Control program under the Safe Drinking Water Aa and RCRJ\. regulatioris associated with
52
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MO!'il~~A POLE ROD. DECISION SL~{MARY
the treatment, storage and transportation of hazardous waste.
Cost-Effectiveness
MDHES and EPA have determined that the selected remedy is cost-effective in mitigating the
principal risks posed by the soils, sediments and contaminated groundwater. Section
300.430(t)(ii)(D) of the NCP requires evaluation of cost-effectiveness. The remedy must
provide overall effectiveness proponional to its costs. Overall effectiveness is determined by
the following three balancing criteria: long-term effectiveness and permanence; reduction of
toxicity, mobility or volume through treatment; and short-term effectiveness. The selected
remedy rates very high in satisfying the first tWo criteria and presents no substantial
problems for short-term effectiveness. To the extent that the estimated cost of the selected
remedy exceeds the costs of other alternatives, the difference in cost is reasonably related to
greater overall effectiveness of the selected remedy.
..
The cost for the selected remedy was estimated by ARCO to be betWeen $27,530,000 to
$55,200,000. MDHES and EPA have detennined that this cost will be reduced to at least
between $26.9 million to $54.7 million and believe that the actUal cost will be near the
bottom end of the range.
.-
....
By comparison, the cost of the containment alternative supported by some of the PRPs in
their commentS was estimated in the feasibility stUdy at betWeen $21.1 million and $36.6
million, and the agencies believe that, fairly assessing the present value of the costS of
perpetUal operation of that system, the actUal costs should be viewed as at the high end of
that range.
Based on data provided by ARCO in the feasibility study report, the selected remedy for the
soils (biological land treatment) provides the best overall effectiveness of all alternatives
considered proportional to its cost. The selected remedy will reduce the toxicity, mobility,
and volume of contaminated soils to the maximum extent practicable. Also the
implementation of this remedy will result in long-term effectiveness by reducing residual
carcinogenic risks to within the acceptable risk range through permanent treatment.
Soil flushing and in sitU bioremediation of areas beneath Interstate 1-15/90 was thought to be
a more cost effective remediation of this limited area of contamination than demolition and
excavation of the Interstate.
The selected remedy for groundwater provides the best overall effectiveness of all
alternatives considered proportional to its cost. The combination of plume containment via
hydraulic (pump and treat) and physical barriers and In Siru biological treatme :11, will reduce
the toxicity, mobility or volume of affected grou,1dwater and will be a permanent solution.
This groundwater remediation approach, in combination with the source removal
53
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:VIO~lAJ.'iA POLE ROD - DECISION SL~IMARY
accomplished by the soil remediation, is believed necessary in order to adequately protect
Silver Bow Creek and the alluvial aquifers. in addition to providing a realistic oppoI1Unity [0
fully stabilize and achieve cleanup goals at the site in rhe future.
The selected remedy assures a high degree of certainty that the remedy will be effective in
the long-tenn because of the significant reduction of the toxicity and mobility of the wastes
achieved through biological treatment of the soil. The groundwater component of the remedy
ens.m:s a high degree of cenainty of effectiveness because the technology employed is known
to be effective for organic contaminated wastewaters and will enhance the degradation of
contaminants remaining in siru.
Utilization of Pennanent Solutions and Alternative Treatment Technolo!!ies (or Resource
Recoverv Technolo!!ies) to the Maximum Extent Practicable
"'""I
!vIDHES and EP A have detennined that the selected remedy represents the maximum extent
to which pennanent solutions and treatment technologies can be utilized in a cost-effective
manner at the Site. Of those alternatives that are protective of human health and the
environment and comply with ARARs, MDHES and EP A have detennined that this selected
remedy provides the best balance of trade-offs in terms of long-tenn effectiveness and
permanence, reduction in toxicity, mobility, or volume achieved through treatment, short-
term effectiveness, implementability and cost" while also considering the statutory preference
for treatment as a principal element and considerlDg state and community acceptance. The
detailed evaluation of the balance of these criteria among the alternatives considered is set
forth in the FS Report and is summarized in section vn, Description of Alternatives, of this
record of decision.
The selected remedy includes treatment of contaminated media which will permanently and
significantly reduce the principal threats posed by the soils and groundwater. The other
alternative considered which could achieve similar or more substantial reductions,
incineration, was significantly more expensive. Other alternatives considered, including
containment, capping and panial excavation, did not offer similar prospects for effectiveness
or permanence.
Preference for Treatment as a Princinal Element
By biologically treating the contaminated groundwater and the contaminated soils, the
selected remedy addresses the principal threats posed by the Site through the use of treatment
technologies. By utilizing treatment as a significant portion of the remedy, tbe statutory
preference for remedies that employ treatment as a principal element is satisfied.
5J
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'.. --
... ,- ~
~10~"'TAl'lA POLE ROD - DECISION SL~L.YL-illY
DOCDi\IE:\lATION OF SIG7'ITFICA.."TT CHA..~GES
XI.
The Proposed Plan for the Site was released for public comment May 5, 1993. The plan
identified Alternative 5B as the prefeITed remedy for the site. MDHES and EP A have
reviewed all written and oral comments submitted during the public comment period. After
consideration of the public comments, MDHES and EP A have determim:d that changes to the
Proposed Plan are warranted.
Comments received from ARCO and Butte-Silver Bow government indicate that funher
restrictions on land and groundwater use at the site are likely. Based on these anticipated
changes, the agencies have modified the preferred remedy as follows:
o
Soil cleanup levels have been modified anticipating that residential land use at
the site will be effectively prohibited. As such, revised soil cleanup levels
have been detennined which will be protective for the anticipated industrial
and recreational uses. Revised soil cleanup levels are based on a 1 in
1,000,000 cancer risk level for recreational land use at the site for each
contaminant of concern for the most susceptible exposure pathway. Soil
cleanup levels are fully explained in Section IX - Cleanup Levels.
o
Groundwater points of compliance have been modified anticipating that access
and use of site contaminated grouudwater will be effec~vely prohibited.
Points of compliance have been set at the waste management area boundary as
explained in Section IX - Points of Compliance. These requirements will be
protective of sUITOunding groundwater and Silver Bow Creek, and are fully
consistent with the NCP and CERCLA requirements.
o
Recognizing the concerns expressed in the PRP comments about the
implementability of excavation below the groundwater table, excavation will be
to the extent practicable, as detennined by the agencies. Contaminated soils
which remain will be addressed by in-site bioremediation.
o
Soil washing was retained in the Proposed Plan as an optional soil treatment
technology. However, upon review of additional treatability studies conducted
by EP A at the site on soil washing, the agencies have detennined that soil
washing does not provide significant advantages over biological treatment,
either in cost or effectiveness, to warrant retaining the technology further.
55
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MONTAl~A POLE ROD - DECISION Sl,~lNl-\RY
xn.
REFERE~CES
Atlantic Richfield Company (ARCO). 1993a. Final Remedial Investigation Report, Montana
Pole and Treating Plant NFL Site. Prepared by James M. Montgomery, Consulting
Engineers, Inc., February 1993.
-' 1993b. Final Feasibility Study, Montana Pole and Treating Plant NFL Site.
Prepared by James M. Montgomery, Consulting Engineers, Inc., March 1993.
Calgon Carbon Corporation, 1991. Accelerated Column Testing for Removal of
. Pentachlorophenol (PCP) and Naphthalene from a Groundwater Stream. Prepared for
Keystone, September 1991.
CDM, 1993. Final Baseline Risk Assessment f01 the Montana Pole NPL Site. Denver,
Colorado.
""1
EPA (U.S. Environmental Protection Agency). 1991. Risk Assessment Guidance for
Superfund. Volume I; Human Health Evaluation Manual, Supplemental Guidance
"Standard Default Exposure Factors." Maxch.
. 1989a. Risk Assessment Guidance for Superfund, Human Health Evaluation
Manual, Volume I. Interim Final. OSWER Directive 9285.701A, Office of Solid
Waste and Emergency Response. Washington, D.C.
. 1989b. Interim Procedures for Estimating Risks Associated with Exposures to
Mixtures of Chlorinated Dibenzo-p-dioxins ano -Dibenzofurans (CDDs and CDFs)
and 1989 Update. EPA/625/3-89/016. March.
. 1989c. Exposure Factors Handbook. Exposure Assessment Group, Office of
Health and Environmental Assessment. Washington, D.C. EPA-600-8-89-043.
May.
. 1989d. Interim Final Guidance for Soil Ingestion Rates. Office of Solid Waste and
Hazardous Waste. OSWER Directive 985.04.
. 198ge. Guidance on Preparing Superfund Decision Documents, Office of
Emergency and Remedial Response, Interim Final, EPA/540/G, July 1989.
Freeman, Harry M., 1989. Standard Handbook of Hazardous Waste Treatment and
Disposal, McGraw Hill, New York, N.Y.
56
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:VI0~1..\.~A POLE ROD - DECISION St.~l\L;\RY
K~ystone, 1991a. Supplemental Work Plan for Additional Work FoUowing the Fill
Sampling. Prepared for ARC a , April 1991.
Ke:.stone, 1991b. Alternative Screening Document Montana Pole and Treating Plant Site,
Bune Montana. Prepared for ARCa, July 1991.
Woodward-Clyde, November 1988. Feasibility Srudy for Site Remediation, Libby, MT.
:l
-
57
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yl0~TA..~A POLE ROD - DECISIO~ Sl,y[\:l-illY
......
.
-
TABLES
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TABLE 1
CONTAMINATED SOIL VOLl~1E ESTL\lATES
II
Soils
Volume yd3
II
3. Soils Excavated ;or Groundwater Extraction System
4. Contaminated Surface soils"
5. Contaminated Surface and Subsurface soilsd
6. Accessible LNAPL "smear zone" soils'
\0.000
6.000
i,OOO
10,000
82,000
93,000
I. Bagged Soils'
2. Contaminated Near Creek Soiisb
7. Soils overlying accessible LNAPL "smear zone" soilsf.
Northern portion of site
Southern portion of site

8. Inaccessible soils'
28,000
66,000
4 1. 000
d
Soils previously excavated and stored on-site.
Near-creek soils are those soils north of the Gundlwall constructed during USEPA's 1992 removal action
at the site and covers an area of about 750 feet long by 50 feet wide.
Areas marked Contaminated Surface Soils on Figure 17; volume from ground surface to 3 feet below
ground surface.
Areas marked Contaminated Surface and Subsurface Soils on Figure 17, volume from ground surface to
4 feet below groundwater surface. .
Areas markecI on Figu!'~ 13 associated with the LNAPL plume. Volume includes soils from 2 feet above
groundwater surface to 4 feet below groundwater surface. Volume excludes the area accounted by
surface/subsurface soils in #5 above and soils beneath the highway.
Areas of uncontaminated soils which overlie accessible LNAPL "smear zone" soils shown on Figure 13.
Inaccessible soils beneath interstate highway include approximately 37,000 yd3 associated with the
LNAPL "smear zone" as shown on Figure 13 and approximately 4,000 yd3 of surface/subsurface soils
shown in Figure 17.
-
..,J
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TABLE 2
PRELThnNARY REMEDIAL ACTION GOALS FOR SOILS
(concentrations in mg/Kg)
Chemic.aJ
Residential Land
Use
Industrial Land
Use
Trespasser or
Recreational
Land use
Pentachloror henolo
Dioxins/Furansb
P AH (Carcinogenic)bc
3
0.00001
0.2
9
0.00003
0.7
34
0.0002
4.0
Levels correspond to an excess cancer risk of 1 x 10" and are based on data for the dermal exposure
pathway as presented in the Baseline Risk Assessment Report (CDM. 1993).
Levels correspond to an excess cancer risk of 1 x 10'" and are based on data for the soil ingestion
exposure pathway as presented in the Baseline Risk Assessment Report (CDM, 1993).
Levels are based on benzo(a)pyrene (BAP) equivalents using the toxicity equivalence factors (TEFs) as
described in the Baseline Risk Assessment Report (CDM, 1993).
-4
,
-------
TABLE 3
C01'o'T.~"1L"A.'\jlS OF CO~CER."i FOR HC\l.\.'\ HEALTH
GROUNDW A TER
SOIL
.....
,
Arsenic
Chromium (VI)
Copper
Lead
Manganese
2-chlorophenol
4-chloro- 3-methylphenol
2,4-dichlorophenol
2,4-dinitrophenol
2,4-dinitrotoluene
Dioxins/Furans
2 -meth y 1-4, 6-d initropheno I
Acenaphthene
Anthracene
Benzo(a)anthracene
. Benzo(a)pyrene
Benzo(b )fluoranthene
Benzo(g,h,i)perylene
Benzo(k)fluoranthene
Chrysene
Dibenzo( a,h )anthracene
Fluoranthene
Fluorene
Indeno( 1 ,2,3-cd)pyrene
2-methyl naphthalene
Naphthalene
Phenanthrene
Pyrene
PentaChlorophenol
2,3,5,6-tetrachlorophenol
2,4,6-trichlorophenol
Arsenic
4-chloro- 3-methylphenol
Dioxins/Furans
2-methyl-4,6-dinitophenol
Anthracene
Benzo(a)anthracene
Benzo(a)pyrene
Benzo(b )fluoranthene
Benzo(k)fluoranthene
Indeno( 1 ,2,3-cd)pyrene
Pentachlorophenol
2,4,6-trichlorophenol
SURFACE WATER
Arsenic
Copper
Lead
Benzo( a) anthracene
Benzo(a)pyrene
Benzo(b )fluoranthene
Chrysene
9 ibenzo ( a,h )anthracene
Pyrene
Pentachlorophenol
Zinc
SEDIMENTS
Arsenic
Dioxins/Furans
Lead
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TABLE ~
POTE~1l-\.L EXPOSCRE PA TIDY.-\. 'is C~1)ER
CURRE:";1 L\. ,\1) t:SE CO:\1)ITIO~S
~
Exposure Medium Potential Routes of Potential Pathway Potential for Chemical
 Exposure Receptors Complete  Exposure
Soil Dermal absorption, Trespassers Yes High. Potential for
 incidential ingestion   trespassers to contact
    surface soil high.
Surface Water and Dermal absorption, Trespassers Yes High for trespassers.
Sediments in Silver incidential ingestion   Children are reported to
Bow Creek    swim in Silver Bow
    Creek, contaminants are
    present in surface water
    and sediment.
Air Inhalation of Residents Yes Moderate. Potential for
 volatile organics located down  fugitive dust generation
 and fugitive dust wind of the site  and volatilization of
    organics from soil is
    moderate. 
Groundwater Ingestion, dermal Trespassers No Low. Groundwater is
 absorption, and   not used for drinking
 inhalation while   purposes. 
 showering     
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.. ~-
TABLE 5
POTE:'Io'TlAL EXPOSL"RE p.-\TH\V.-\YS L~"DER
FL"lu"RE LA."'1> USE CONDITIONS
~
 Exposure Potential Routes of Potential Potential for Chemical
 Medium Exposure Receptors  Exposure
Soil  Dermal absorption, Future on-site High. Children are especially
  incidental ingestion residents, workers likely to play on soils.
Surface Water Dermal absorption, Future on-site High. Children are especially
and Sed iments in incidental ingestion residents, workers likely to swim and wade in
Silver Bow Creek   creek.  
Air  Inhalation of volatile Future on-site High. Potential for fugitive dust
  organics and fugitive residents, workers generation and volatilization of
  dust  organics from soil is high.
Groundwater Ingestion Future on-site High. Contaminants are present
   residents, workers in groundwater."
Produce Ingestion Future on-site Moderate. Uptake of
   residentS, workers contaminantS in groundwater and
    soils by plants is likely to
    occur~ b  
Assumes that drinking water wells may be installed in the future. Actual potential for on site
residential development appears to be low.
Assumes that gardening in the Butte area will be limited by climate.
-------
...,
'C -..
TABLE 6
EXPOSL"RE ASSLI\1PT10NS FOR DER'L.\L CONTACT WITH SL'RFACE SOIL
FOR WORKERS (FCTLTRE) .~'\'D TRESPASSERS (CljRRE:'-ol)
I Parameter I Exposure Assumption. I
Frequency of Exposure  
Workers (future)  150 d/yr" 
Trespassers (current)  60 d/yrb 
Period of Exposure   
Workers (future)  25 yr" 
Trespassers (current)  12 yr>" 
Skin Surface Area   
Workers (future)  3,120 cmH 
Trespassers (current)  5,165 cmH 
A verage Body Weight   
Workers (future)  70 kgt 
Trespassers (current)  43 kg' 
A veraging Time    
Noncarcinogens  365 d/yr x 25 yf (worker) 
   365 d/yr x 12 yr (trespasser) 
Carcinogens   365 d/yr x 70 yrA . 
Skin Adherence Factor  1.45 mg/cm24 
Fraction Contaminated   
Workers (futUre)  1.0 
Trespassers (current)  0.5 
Absorption Factor   
Organics   0.1 
Inorganics &. Dioxins/Furans  0.01 
surc Factol'$ Handbook. Office of Health and Environmental
Assessment. EP N600-8-89/043.
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TABLE 7
EXPOSURE ASSIDIPTION3 FOR
I:\'CIDEYrAL INGESTION OF Sl..lU'ACE SOIL
FOR WORKERS (F1.7rCRE) A..~1) TRESPASSERS (Cl.."RRE~T)
""")...
I Parameter I Exposure Assumption I
Frequency of Exposure I  
Workers (futUre)  150 d/y~ 
Trespassers (current)  60 d/yrb 
Exposure Duration   
Workers (future)  25 yr" 
Trespassers (current)  12 yrD 
Ingestion Rate    
Workers (futUre)  100 mg/dayc.. 
Trespassers (current)  100 mg/dayc.. 
A verage Body Weight   
Workers (futUre)  70 kg" 
Trespassers (current)  43 kg( 
Fraction Ingested    
Workers (futUre)  1.0 
Trespassers (current)  0.5 
Based on exposure occurring 5 days a week for 7 months of the year (5/7 x 210 = 150).
Based OD exposure occurring 2 times a week (2/7 x 210 = 60).'
EPA (1989a. 1991).
Current exposure is for trespassers ages 6 through 18.
EPA (1989d). Interim Final Guidance for Soil [ngestion Rates. Office of Soljd Waste and
Emergency Response. (OSWER Directive 9850.4)
EPA (1989c). Exposure Factors Handbook. Office of Health and Environmental
Assessment. EP A/600-8-89/043.
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TABLE 8
EXPOSLltE ASSC:\1PTIONS FOR
DIRECT CONTACT A.,\1) INCIDE:\iAL I;-.tGESTION OF SCRFACE WATER
~
I Parameter ~ Exposure Assumption 1
I Frequency of Exposure 
Trespassers (current)  43 d/y~ 
Exposure Duration    
Trespassers (current)  12 yr> 
Skin Surface Area    
Trespassers (current)  13,050 cm: '
Exposure Time    
Trespassers (current)  2 hr/day' 
Average Body Weight  43 kgd 
Ingestion Rate   50 ml/hr' 
Fraction Contaminated  0.5 
Permeability Constant  8.4 E-04 cmlhr' 
Based on exposure occurring tWice a week for 150 days (2/7 x 150 = 43)
Exposure is for a trespasser ages 6 through 18
EPA (1989a)
EPA (1989c). EXDosure Factors Handbook. Office of Health and Environmental
Assessment. EP A \600\8-89\043.
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TABLE 9
EXPOSCRE ..\SSL~1PTIO:' 
Skin Surface Area    
Trespassers (current)  13,050 cm2< 
Average Body Weight   
Trespassers (current)  43 kgt 
Skin Adherence Factor  2.0 mg/cm: '
AbsorptiOn Factor   0.1. 
   O.Olr 
Ingestion Rate    
Trespassers (current)  50 mg/dayb 
Fraction Contaminated  0.5 
d
Based on exposure occurring twice a week for 150 days (2/7 x 150 = 43)
EP A (1989a)
Current exposure is for a trespasser ages 6 through 18
EPA (1989c). Exposure Factors Handbook. Office of Health and Environmental
Assessment. EP A \600\8-89\043.
For organic compounds other than dioxins/furans.
For inorganic compounds and dioxins/furans.
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TABLE 10
EXPOSt;RE ASSL"\IPTIO~S FOR
DER.'lAL CO:-ITACT WITH SL"RFACE SOIL
FOR RESIDE~"TS (F1.;Th"RE)'
~
I Parameter I Exposure Assumption I
Frequency of Exposure  
Children (future)  350 d/yrb 
Residents (future)  350 d/yr 
Period of Exposure   
Residents (future)  30 yrb 
Children (future)  10 yrb 
Skin Surface Area   
Residents (future)  3,476 cm2 c 
Children (future)  4,187 cm2c 
Average Body Weight   
Residents (future)  59 kg" 
Children (future)  19 kg' 
A veraging Time    
Noncarcinogens  365 d/yr x 30 yr' (resident) 
   365 d/yr x 12 yr (child) 
Carcinogens   365 d/yr x 70 yr' 
Skin Adherence Factor  1.45 mg/cm2 C 
Fraction Contaminated  0.7 
Absorption Factor   
Organics   0.1 
lnorganics & Dioxins/Furans  0.01 
...
Chronic daily intakes (CDls) for estiminating cancer risks to future residents are
conservatively based on exposure during the first 30 years of life. CDls for
estimating non-<:ancer risks are conservatively based on exposure for children ages
o to 10 years old.
b EPA (1989a).
EPA (1989a,c). 50th percentile body surface area for adult forearms and hands
were used for adult residents; forearms, hands, and legs were used for children
ages 0 through 10.
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TABLE 11
EXPOSL"RE. ASSC~1PTIO~S FOR
I~CIDE:\lAL INGESTIO~ OF SCRFACE SOIL
FO R RESID E~'TS (FLll.-"RE)'
..
I Parameter -r Exposure Assumption I
Frequency of Exposure  
Children (futUre)  350 d/yrb 
Residents (futUre)  350 d/yrb 
Exposure Duration    
Residents (futUre)  30 yrb 
Children (futUre)   10 yrb 
Ingestion Rate    
Residents (futUre)  120 mg/day'.d 
Children (futUre)   160 mg/day". 
Average Body Weight   
Residents (futUre)  59 kgb 
Children (futUre)   19 kgb 
Fraction Ingested    
Residents (futUre)  0.7 
Children (future)   0.7 
"=\
CDIs for estimating cancer risks to futUre residents are conservatively based on exposure
during the first 30 years of life. CDIs for estimating non-cancer risks are conservatively
based on exposure for children ages 0 to 10 years old.
EPA (1989a).
EPA (l989d). Interim Final Guidance for Soil In~estion Rates. Office of Solid Waste and
Emergency Response. (OSWER Directive 9850.4)
Soil ingestion prorated for incidental ingestion of 200 mg/day for ages 0 to 6 and 100
mg/day for ages 6 to 30.
Soil ingestion prorated for incidental ingestion of 200 mg/day for ages 0 to 6 and 100
mg/day for ages 6 to 10.
-------
TABLE 12
EXPOSL"RE ASSL~1PTIO:\S FOR
L'iGESTION OF HO!\lE GRO\V~ YEGETABLESb
~
I Parameter ~I Exposure Assumption I
Frequency of Exposure  
Residents (furore)  52 d/yr 
Children (furore)  52 d/yr 
Exposure Duration    
Residents (furore)  30 yr> 
Children (furore)  10 yr 
Ingestion Rate    
Vine Crops   151 g/day 
Leafy Crops   144 g/day 
Root Crops   114 g/day 
Body Weight    
Residents (furore)  59 kg 
Children (furore)  19 kg 
A veraging Time    
. Noncarcinogen   365 d/yr x 10 yrs 
Carcinogen   365 d/yr x 70 yrs 
Fraction Absorbed   1" 
For compounds other than pentachlorophe~ol.
CD Is for estimating cancer risk to future residents are conservatively based on exposure
during the first 30 years of life. eDis for estimating non~ancer risks are conservatively
based on exposure for children ages 0 to 10 years old.
EPA (1989a).
For arsenic, absorption is assumed to be 80 percent.
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4 -.
TABLE 13
EXPOSURE ASSl,~IPTIO~S FOR
L'lGESTION OF HOME GRO'V~ VEGETABLES
GROWN L'l SOIL COi'lAL'HNG PE:\'TACm..OROPHE~OL'
:1
I Parameter J Exposure Assumption J
Frequency of Exposure   
ResidentS (futUre)  52 d/yr 
Children (futUre)  52 d/yr 
Exposure Duration    
ResidentS (futUre)  6 yrb 
Children (futUre)   6 yr 
Ingestion Rate    
Root Crops   114 g/day 
Body Weight    
ResidentS (futUre)  59 kg 
Children (futUre)   19 kg 
A veraging Time    
Noncarcinogen   365 d/yr x. 6 yr~ 
Carcinogen   365 d/yr x 70 yr1' 
Fraction Absorbed   1b 
EPA (1989a).
For arsenic, absorption is assumed to be 80 percent.
-------
'c -..
TABLE 1~
EXPOSt:RE ASSt.}.[PTIO~S FOR
INGESTIO~ OF GROl.;.;1)WATER'
~
I Parameter ~ Exposure Assumption \
Frequency of Exposure   
Residents (future)  350 d/yr> 
Children (future)  350 d/yr> 
Exposure Duration    
Residents (futUre)  30 yr> 
Children (futUre)  10 yr 
Ingestion Rate    
Residents (futUre)  2L/db 
Children (future)  2L/db 
Body Weight    
Residents (future)  59 kgi' 
Children (future)  19 kgi' 
A veraging Time    
Noncarcinogen   365 dJYr x 10 yrsb 
Carcinogen   365 d/yr x 70 yrsb 
-
.
eDls for estimating cancer risk to future residents are conservatively based on exposure
during the first 30 years of life. CDIs for estimating non-cancer risks are conservatively
based on exposure for children ages 0 to 10 years old.
EPA (1989a)
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TABLE 15
EXPOSL"RE PO~l CONCDiTRATIO;\S FOR
SCRFIClAL SOILS (JLgikg)
:1
I I Southern Area ! Northern Area !
Anthracene  5..OJ  224.95 
Benzo( a)anthracene  20.25  6825.61 
Benzo(b )fluoranthene  18.30  476.06 
Benzo(k.)fluoranthene  8.74  457.42 
Benzo(a)pyrene  12.04  270.23 
lndeno(1 ,2.3-cd)pyrene  15.99  338.89 
4-chloro- 3-methy Iphenol  765.09  6605.55 
2-methyl-4,6, -dinitrophenol  11445.54  14759.28 
Pentachlorophenol  319070.4  61943.0 
2,4, 6-trich1oropheno I  1492.55  7212.23 
OCDD  46.79  5020 
1234678-HpCDD  4.23  469 
1234789-HpCDF .013  12.9 
123789HxCDD .019  1.7 
123678HxCD D .126  14.9 
123478HxCDD .015  1.4 
12378PeCDD ,004  0.0067 
2378-TCDF  . .002  0.421 
2378-TCDD .008  0.0106 
1234678-HpCDF .298  81.8 
123678HxCDF .0371  2.6 
234678HxCDF .0142  2 
123789HxCDF  0  0.00056 
123478HxCDF .037  17.1 
OCDF .i87  433 
23478PeCDF .0049  2.2 
12378PeCDF .0064  2 
Arsenic  40985.21  147177.10 
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TABLE 15 (Cont.)
EXPOSL"RE PO~"T CO:\CE:\"TRATlO:"S
SVRFIClAL SOILS (;Lgikg)
I I Southern Area ! Northern Area !
Cadmium  789.25  1862.56 
Chromium  11047.69  9829.16 
:1
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TABLE 16
EXPOSLlffi POI:-"l CONCEXfRATIO~S
FOR GROl;~l)WATER
..,
~
I I ~/L !
Acenaphthene  474.08
Acenaphthylene  238,069.08 
Anthracene  259.85 
Benzo(a)pyrene  69.63 
Benzo(a) anthracene   7,199.97 
Benzo(b )fluoranthene  0.18 
Benzo(g,h, i)perylene  9.62 
Benzo(k)fluoranthene  35.89 
Chrysene  19,805.83 
Dibemo( a,h)anthracene  18.75 
.   
Fluoranthe'le  421.12 
Fluorene  42,850.20 
Indeno(1 ,2,3~d)pyrene  1.29 
2-med1ylnapbthalene  4,039.26 
Naphthalene  4,259.54 
Phenanthrene  3,817.27 
Pyreoe  848.02 
~bloro-3-methylphenol  331.13 
2, 4-dichloropbenol  985.15 
2-med1yl-4 ,~initropbenol  381. 94 
2,3 ,5,6-tetrach1oropbenol  3,090.53 
2,4,6-ttichlorophenol  231. 89 
PentaChlorophenol  6,506.98 
2~orophenol  40.47 
2,4-dinitrotoluene  220.5 1 
1234678-HpCDD  1.66 
1234678-HpCDF  0.182 
1234789-HpCDF  0.0156 
-------
'.. -.,
TABLE 16 (Cont.)
EXPOSCRE POI!,;! CO!'iCEmRA TIO~S
FOR GROL~l)W ATER
--
~
I I p.gfL I
123678HxCDD  0.0653
123789HxCDD  0.0097 
123478HxCDF  0.0468 
123678HxCDF  0.0085 
234678HxCDF  0.0179 
OCDD  14.96 
OCDF  0.543 
12378PeCDF  0.0072 
23478PeCDF  0.007 
Arsenic  23.14 
Chromium  28.39 
Copper  139.51 
Lead  29.68 
Manganese  2,493.35 
..-
95 percent upper confidence limit on geometric mean unless otherwise
noted.
95 percent upper confidence limit on arithmetic mean.
Maximum detected concentration due to limited sample numbers.
b
..
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TABLE Ii
EXPOSURE POL"l CO:\CE~lR-\TIO:'\S FOR
SURFACE WATER .-\.,,1) SEDL\IE~lS
~
I J Surface Water ( SedimentS I
p.gIL ~/kg
Pentachlorophenol   
 591  -
Benzo(a)anthracene  1.5  - 
Benzo( a)pyrene  0.2  - 
Benzo(b )tluoranthene  0.4  - 
Chrysene  9.0  - 
Dibenzo( a,h )anthracene  0.6  - 
Pyrene  1.36  - 
Dioxins/Furans  -  1.4 
Arsenic  24.9  -
copper  220  -
Lead  30  - 
- = not considered a cac for this medium
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TABLE 18
SL~L\'Lo\RY OF ESTIMATED RISKS FOR
F(JTIJRE ON-SITE R.ESIDE~'TS
   Ingestion of 
  Dermal Contact Home-Grown Groundwater
Chemical Soil Ingestion with Soil Vegetables Ingestion
Carcinogenic Exposure    
Pentachlorophenol 2.23£-05 9.41£-05 8.92E-04 1.09E-02
Diox'ins/Furans 1.15£-05 4.83£-06 1.08E-04 I.I0E-OI
2,4,6- Trichlorophenol 9.57E-09 4.03E-08 2.10E-05 3.55E-05
Benzo(a)pyrene (T£Fs) 1.29E-07 NA 4.63E-06 3.09E-02
Arsenic 3.35£-05 1. 76£-05 4.64E-04 5.64E-04
Total Cancer Risk 6.74£-05 1.17£-04 1.49E-03 1.53E-Ol
....    
Noncarcinogenic Exposure    
Pentachlorophenol 6.01E-02 2.28E-ol 5..39E+Ol 2.19£+01
Dioxins/Furans (TEFs) 7.40£-01 2.81£-01 5.20E+00 5.33E+03
2,4,6- Trichloropheno I NA NA NA NA
P AH (Total noncarcinogen) NA NA NA 7.54£+02
2-<:hlorophenol NA NA NA 8.17£-01
Arsenic 6.18£-01 2.93£-01 6.40E+00 7.86£+00
Copper NA NA NA 3.52£-01
Manganese NA NA NA 2.52E+00
Lead NA NA NA NA
Chromium NA NA NA 2.73£-01
2,4-Dichlorophenol NA NA NA 3.31£+01
2,4-Diniuotoluene NA NA NA 3.27E-02
4-Chloro- 3-methyl phenol NA NA NA NA
Anthracene 9.62£-07 NA 2.66£-05 NA
Cadmium 8.92£-03 3.39£-05 1.41E+00 NA
2-methyl-4, 6-<1 initropheno I NA NA NA NA
2,3,5,6- Terrachlorophenol NA NA NA 1.04E +0 1
Total Hazard Index 1.43£+00 8.05E-Ol 6.69E+Ol 6.lcE~03
NA = Not Applicable    
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.. -.
TABLE 19
SL~I:\1ARY OF ESTI~l.\TED RISKS FOR
FFIl.:RE ON-SITE WORKERS
   Dermal  Surface Dermal Contact
  Soil Contact Sediment Water with Surface
 Chemical Ingestion with Soil Ingestion Ingestion Water
 Carcinogenic Exposure  Incremental Lifetime Cancer Risk 
 Pentachlorophenol 8.03E-06 3.63E-05 NA NA NA
 Dioxins/Furans (rEFs) 4. 12E-06 1.86E-06 NA NA NA
 2,4,6- Trichlorophenol 3.44E-09 1. 56E-08 NA NA NA
::: Benzo(a)pyrene (TEFs) 4.65E-08 NA NA NA NA
 Arsenic 1.20E-05 6.80E-06 NA NA NA
 Total Cancer Risk 2.42E-05 4.50E-05 O.OOE+OO O.OOE+OO O.OOE+OO
   Total C:JJ1cer Risk for all Media 6.92E-05
 Noncarcinogenic   Hazard Index 
 Exposure     
 Pentachlorophenol 6.24E-03 2. 82E-02 NA NA NA
 Dioxins/Furans (rEFs) 7.69E-02 3.48E-02 NA NA NA
 2,4,6-Trichlorophenol NA NA NA NA NA
 2-methy 1-4, 6-dinitrophenol NA NA NA NA NA
 Anthracene 9.99E-08 NA NA NA NA
 Arsenic 6. 42E-02 3.63E-02 NA NA NA
 Cadmium 9.72E-04 4. 19E-04 NA NA NA
 4-Chloro- 3-methylphenol NA NA NA NA NA
 Pyrene NA NA NA NA NA
 Total Hazard Index 1.48£-01 9.91£-02 O.OOE+OO O.OOE +00 O.OOE+OO
   Total Hazard Index for all Media 2..+8E-01
 NA = Not Applicable     
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TABLE 20
Sl,-:\IYL\RY OF ESTI\L\TED RISKS FOR
CURRE~" O~-SITE TRESPASSERS
  DennaJ  Surface Dermal Contact
 Soil Contact Sediment Water with Surface
Chemical Ingestion with Soil Ingestion Ingestion Water
Carcinogenic Exposure  Incremental Lifetime Cancer Risk 
Pentachlorophenol 1.25E-06 9.40E-06 NA 3.33E-06 3.65E-07
Dioxins/Furans (rEFs) 6.44E-07 4. 82E-07 2.47E-09 NA NA
2,4,6- Trichlorophenol 5.38E-I0 4.03E-09 NA NA NA
Benzo(a)Pyrene (rEFs) 7.27E-09 NA NA 4.35E-07 NA
.-.     
Arsenic 1.88E-06 1. 76E-06 NA NA NA
Total Cancer Risk 3.78£-06 1.16£-05 2,47£-09 3.7iE-06 3.65E-07
  Total Cancer Risk for all Media 1.96E-05
Noncarcinogenic   Hazard Inde."I:  
Exposure     
Pentachloropheno I 2.03E-03 1.52E-02 NA 5.4OE-03 5.90E-04
Dioxins/Furans (rEFs) 2.50E-02 1. 88E-02  9.59E-05 NA NA
2,4,6- Trichlorophenol NA NA NA NA NA
2-methyl-4,6-dinitrophenol NA NA NA NA !'-lA
Anthracene 3.25E-08 NA NA NA NA
Arsenic 2.09E-02 1. 96E-02  NA NA NA
Cadmium 3.02E-04 2.26E-04 NA NA NA
4-Chloro- 3-methylphenol NA NA NA NA NA
Pyrene NA NA NA 1.24E-05 NA
Total Hazard Index 4.82E-02 5.38E-02 9.59E-05 5.41E-03 5.90E-04
  Total Hazard Index for all Media 1.08E-Ol
NA = Not Applicable     
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TABLE 21
ESTIMA TED COST FOR RE;o.1EDIAL AL TERNA TIVE 5B
  Soil: Bicremediation (10 y~)   
 Groundware~: OiV'Narer Separation FoUowed by 3iotre:lrment:li1d C:u-bon Polishing 
  Oiiy WasleS :li1d Sludge: OrT-Site [nc:ne:-:Jcon   
        -'
     Lnit Cost Toeal Cost
 Item/Descri~ rion Duration Quantity Unit ~1in. \'tax. Min. \1 ax. 
 CAPITAL COSTS       
 If1Stitwiofl/ll Controls       
 1m plementation 1st ye3I  lump sum 575.000 575.000 575.000 $75.000
 Groundwater Monitoring       
 Well Installation 1st ye3I 4 e3Ch 5 l,1oo 52.000 5-1.800 58.000
 Site Preparation       
 Excavate and Reconstruct I st year 1.000 feet 5100 S150 Sloo.000 5150.000
 Railroad       
 Containmelll       
 Soil Cover 11th yeM 51,1 00 cu. yei. 510 520 5511.000 51.020.000
 Common Borrow 1 st yf::M 16.000 cu. yei. 58 515 5128.000 5240.000
 Trea~nt and Disposal       
 Soil       
 Fixed CostS 1st year 1 lump swn 52.660.000 56.040.000 52.660.000 . 56.040.000
 Tr.msportation 1st yf::M 6.000 cu. yd. S4 S8 S24.000 S48.COO
. Groundwa.leI'       
 Treaanent Facilicy 1 st yf::M  lump sum 5981,000 51.090.000 5981.000 51.090.000
 ExlI'aCrion F acilicy 1st Yf::M  lump sum 5371.000 5557.000 5371.000 5557.000
 Infllaation Facilicy IstYf::M  lump sum 5133.000 5168.000 5133.000 $168.000
 Oily Was~ and Sludge       
 Off-Site Incineration 1st year 30.000 gallon $17 $26 5504.000 $792.000
 Equipment and Debris       
 Mob/DeCon/Disposal IstYf::M  lump sum 51.600.000 $1.720.000 $1.600.000 51.720.000
SUBTOTAL      I 57.090.000 11511,910.000 \
ContraCtors Overhead and Profit @ 20%     51,420,000 52.380.000
ContraCtors Mobilization and Demobilization @ 15%    51.060.000 51.790.000
Engin~g Design @ 20%      51.420.000 52.380.000
Administrative CostS @ 15%      51.063.500 51,786.500
TOTAL CAPITAL REQUIRE;1ENT     1512.050.000 11520.250.000 I
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TABLE 21 (Cont.)
ESTIMATED COST FOR RE~IEDL~L AL TER:-IA TIVE 5B
Soil: Bioremediation (10 ;'e3!s)
Groundwater: Oi1f\Vmr Separ:ltlon :=oUowed by 3icC'::ltrnem IDd C.l!xn ?olishmg
Oily WasteS IDd Sludge: Ofi-Site Incine=:luon
     L !lit Cost  Total Cost
 ItemiDescriptioD D'JratioD Quantity tnit \1 in.  \1 ax.   ~liD. :\1 ax.
 OPERATION AND MAINTE."IA.'KE COSTS       
 In.srirwion.al Controls        
 Instionionai COnlrols Year 1 - 30  lump sum $10.000 510.000  510.000 510.000
 Five Year Site Review Every 5 yean  lump sum 540.000 . 560.000  540.000 560.000
 Groun.dwat~r Monitoring        
 Anal ytical/Reportin g Year 1 . 30  Ye:Jr $70.000 5151.000  570.000 5151.000
 Conra~nt        
 Cover Maintenanc: Year 12 . 30  lump sum 530.000 550.000  530.000 550.000
Tr~armtnt and Disposal        
.....,        
 Soil        
 ExcavationIBadcfill Year 1 - 10 29.100 cu. yd. 517 575  5500.000 52.190.000
 Dewatering removed soils Year 1 - 10 11.400 cu. yd. 53 520  534.000 5228.000
 Bioremediarion Year 1 . 10 20.700 cu. yd.. 526 534  5534,000 5708.000
#J Groundwater        
Biort3CtOf Year 1 - 30 72.580 1.000 gallons 57 514  5510.000 51.033.000
 Oily WasteS and Sludge        
 Off-Site Incineration Year 2 - 30 3.500 gallon 517 526  558.800 592.400
Annual coSt for year 1      I 51.670.000 II 54.330.000 I
Annual cost for YCU'S 2 . 10      I 51.720.000 I [ S4.420.ooo I
Annual cost for year 11      r 5657.000 II 51.298.000 I
Annual cost fOf years 12.30      I $687.000 (I 51.348.(XX)]
PRESENT WORTH
Duration
Discount ..lIC
30 years
7 percent
1527.530.000 11555.200.000 t
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TABLE 11
ESTnlATED COST FOR SOIL FU':SHl~G SYSTE:\l
Present Worth Basis
(for 15 gpm system)
""\
   Unit Cost Total Cost
ItemIDescription Quantity Unit :\1in. Max. Min. Max.
CAPITAL COSTS      
Hydraulic Srudy I lump sum $15,000 $50,000 $15,000 $50,000
Pilot Test 1 lump sum $30,000 $50,000 $30,000 $50,000
Well Installation 12 each $1,200 $2,000 $14,400 $24,000
Piping Installation 1,000 I inear ft. $30 $50 $30,000 $50,000
   Total Capital Costs $89,400 $174,000
OPERATION AND MAINTENANCE COSTS    
Annual Costs      
Carbon Usage(a) 1 lump sum $8,000 $13,000 $8,000 S13,000
Labor 0.5 FTE $20,000 $40,000 $10,000 $20,000
   Total Annual Costs $18,000 $33,000
PRESENT WORTH      
Duration = 30 Years      
Discount Rate = 7 Percent     
TOTAL     $328,000 $612,000
(a) Costs are based on estimated carbon usage rate of 0.5 Ibs. carbon per 1,000 gallons of groundwater
treated. This estimate was provided by Calgon for removing PCP and naphthalene from groundwater
(Calgon, 1991).
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-... --
TABLE 13
SOIL CLEA.~l;1> LEVELS k~TI CORRESPO~TIING RISKS
  I   ~oncancer. health i
'Iedia Contaminant Cleanup level Basis Cancer Risk
  (;Lg/kg)  (recreational use hazard quotient \
    for soil)  
Soils P ~ntacbJorophenol' 34,000 risk 1.0 X 10-6 <1 
 B2 PAHs (TEF)'" 4,200 risk 1.0 X 10-6 < 1 
 Dioxin TCDD (TEF)bcI 0.20 risk 1.0 X 10-6 <1 
NA - Not applicable
Levels correspond to an excess cancer risk of 1 x 1~ and are based on data for the dermal exposure pathway as
presented in the Baseline Risk Assessment Report (CDM, 1993).
Levels correspond to an excess cancer risk of 1 x W. and are based on data for the soil ingestion exposure pathway
as presented in the Baseline Risk Assessment Report (CDM, 1993).
Sum of individual B2 PAH (benzo(a)anthracene. benzo(b)fluoranthene. benzo(k)fluoraothene, benzo(a)pyrene.
benzo(g.h.i)perylene. chrysene. dibenzo(a.h)anthracene. and indeno(l.2.3-cd)pyrene) concentrations multiplied by their
corresponding toxicity equivalence factor (TEFs) r.s shown on Table 28.
Sum of individual cbJorinated dibenzo-p-dioxins and -dibenzofurans concentrations multiplied by their corresponding
toxicity equivalence factor (TEF) as shown on Table: 29.
~
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TABLE 24
PATHWAY RISK ESTIMATES
CORRESPONDING TO SOIL CLEANUP LEVELS
Recreational Soil Pathway Cancer Risks
   Risk 
Chemical Cleanup Level (ug/kg) Ingestion Dermal Total eoe
Pentachlorophenol 34000 1.33E-07 1.00E-06 1 .1 4E - 06
Dioxins/Furans (TEFs) 0.2 9.a3E-07 7.36E-07 1.72E-06
82 PAH (TEFs) 4200 1.00E-06  1.00E-06
 Total Pathway 2.12E-06 1.74E-06 
-----------------------------------
Industrial Soil Pathway Cancer Risks
Chemical
Cleanup Level (ug/kg)
Ingestion
-
....
..- Pentachlorophenol
Dioxins/Furans (TEFs)
82 PAH (TEFs)
34000
0.2
4200
a.S6E-0?
6.29E-06
6.42E-06
T ota! Pathway
1.36E-05
-----------------------------------
2.00E-05
Total
Risk
Dermal
3.5aE-06
2.84E-06
6.42E-06
Total
3.86E-06
Total COC
4.44E-06
9.13E-06
6.42E-06
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TABLE 25
GROl:;..'DWATER CLEAJ""L-P LEVELS :\.."TI CORRESPO~TID;G RISKS
....,.
Media Contaminant Cleanup level Basis Cancer Risk ~oncancer
  (pgll)  (drinking use for health hazard
    ground water) quotient
Groundwater Pentachlorophenol 1.0 MCL 1.7 X 10-4 NA
 Benzo(a)pyrene 0.2 MCL 2.1 X 10-' NA
 Benzo(a)anthracene 1.0 risk 1.0 X 10-4 NA
 Benzo(b)fluoranthene 0.2 risk 2. 1 X to., NA
 Benzo(k)fluoranthene 1.0 risk 1.0 X 10-4 NA
 Chrysene 1.0 risk 1.0 X 10-4 NA
 Dibenzo( a.h)anthracene 0.2 risk 2. 1 X 10" NA
 Indeno( 1.2.3-CD)pyrene 1.0 risk 1.0 X 10-6 NA
 Benzo(g,h.i)perylene 1.0 risk 1.0 X 10-6 NA
 Total D PARs' 360 hazard quotient NA 0.9
 Dioxin TCDD (TEF)" 3.0 x lO-s MCL 6.2 x lO's <1
 2.4.6-bichlorophenol 6.5 risk 1.0 X 10-6 NA
 2-chlorophenol 45 hazard quotient NA 0,9
 2.4-dichlorophenol 27 hazard quotient NA 0.9
 I 2.3.5 .6-tetrachlorophenol 267 hazard quotient NA 0.9
NA - Not applicable
Sum of individual D PAR (acenaphthene. acenaphthylene. anthracene. fluoranthene. fluorene. naphthalene.
phenanthrene. pyrene) concentrations.
Sum of individual chlorinated dibenzo-p-dioxins and -dibenzofurans concentrations multiplied by their corresponding
toxicity equivalence factor (TEF) as shown on Table 29.
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TABLE 16
St.TRFACE WATER CLEA..'\TP LEVELS A.'\"D CORRESPO:\"DI~G RISKS
~
     ,
:\ledia Contaminant Cleanup level Basis Cancer Risk ~oncancer
  0-tgl\)  (drinking use for health hazard
    surface water) quotient
Surface Pentachlorophenol 1.0 MCL 1.7XI0~ <\
~'ater     
 Benzo( a)pyrene 0.2 MCL 2.1 X 10.5 NA
 Benzo( a)anthracene 1.0 risk 1.0 X \O~ NA
 Benzo(b )fluoranthene 0.2 risk 2. \ X 10.5 NA
 Benzo(k)fluoranthene \.0 risk 1.0 X IO~ NA
 Chrysene 1.0 risk 1.0 X 10~ NA
 Dibenzo( a. h)an thracene 0.2 risk 2. 1 X 10.5 NA
 Indeno( 1,2.3-CD)pyrene 1.0 risk 1.0 X 10~ NA
 Benzo(g,h.i)perylene 1.0 risk 1.0 X 10~ NA
 Total D PARs" 360 hazard quotient NA 0.9
 Dioxin TCD~ (TEF)b 1.0 x 10,5 aquatic criteria 2.0 x 10,5 <1
 2,4.6-trichlorophenol 6.5 risk 1.0 X IO~ NA
 2-chlorophenol 45 hazard quotient NA 0.9
 2,4-dichlorophenol 27 hazard quotient NA 0.9
 2.3.5.6-tetrachlorophenol 267 hazard quotient NA 0.9
NA - Not applicable
Sum of individual D PAH (acenaphthene. ac:naphtbylene, anthracene, fluoranthene. fluorene. napbthalene,
phenanthrene. pyrene) concentrations.
Sum of individual chlorinated dibenzo-p-dioxins and ~J;benzofurans concentrations multiplied by their corresponding
toxicity equivalence factor (TEF) as shown on Table 29.
-------
TABLE 27
DISCHARGE TO S1.:RFACE WATER CLEA.';1."P LEVELS A..,\1) CORRESPO;..1)I~G RISKS
-
..'
Media Contaminant Cleanup level \ Basis  Cancer Risk :'-ioncancer \1
  (;Lgl\)    (drinking use for health hazard \
      surface water) quotient
Discbarge to Pcntachloropbenol 1.0  MCL  1. 7 XIO~ < I 
Surface        
Water        
 Benzo(a)pyrene 0.2  MCL  2. I X lO's NA 
 Benzo(a)anthraccne 1.0  risk \ 1.0 X 10.7 ~A 
 Benzo(b )fluorantbcne 0.2  risk  2.1 X lO's NA 
 Benzo(k)fluoranthenc 1.0  risk  1.0 X 10~ NA 
 Chrysene 1.0  risk  1.0 X 1O~ NA 
 Dibenzo( a.h)anthracene 0.2  risk  2. I X lO's NA 
 lndeno( 1.2.3-CD)pyrene 1.0  risk  1.0 X 1O~ NA 
 Benzo(g,h.i)perylene 1.0  risk  1.0 X 10~ NA 
 Total D PAHs" 360  hazard quotient  NA 0.9 
 Dioxin TCDD (TEF)b 1.0 x lO's  aquatic criteria  2.0 x lO's <1 
 2. 4.6-trichlorophenol 6.5  risk  1.0 X 1O~ NA 
 2-chlorophenol 45  hazard quotient  NA 0.9 
 2.4-dichlorophenol 27  hazard quotient  NA 0.9 
 2.3.5 .6-tetrachlorophenol 267  hazard quotient  NA 0.9 
 Arsenic 48  aquatic criteria  NA NA 
 Cadmium 1.1  aquatic criteria  NA NA 
 Chromium 11  aquatic criteria  NA NA 
 Copper 12  aquatic criteria  NA NA 
 Lead 3.2  aquatic criteria  NA NA 
 Zinc 110  aquatic criteria  NA NA 
NA .. Not applicable
Sum of individual D PAH (accnapbthcnc. acenapbthylene. anthracene. fluoranthcnc. fluorene. naphthalene.
phenanthrene. pyrene) concentrations.
Sum of individual chlorinated dibenzo-p-dioxins and -dibenzofurans concentrations multiplied by their corresponding
toxicity equivalence factor (rEF) as shown on Table :9.
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\ j
TAIILE 28
ESTIMATED TOXICITY EQUIVALENCE FACTORS AND POTENCY ESTIMATES FOR PAils
    Resulting OSWER
 Relative Potency.   Potency (oral shlile raclor)
Chemical (Chu/Chen 1984) EPA Classification TEF (OSWER) (mg/kg/day)"1
Uenzo(a)allthracene 0.0134 U2b 0.01 7.3 x 101
Uenzo(b )Iluoranthene 0.0800 02 1.0 7.3
Benzo(k) 11 uoranthene 0.0044 82 0.01 7.3x102
Benzo(a)pyrene 1 82 1.0 7.3
Benzo(g,h, i)perylene ND D 0.01 7.3 x 102
Chrysene 0.0012 02 0.01 7.3 x 102
Dibenz(a ,h)anthracene 0.6900 82 1 7.3
Indeno( 1 ,2,3-cd)pyrene 0.0171 82 0.01 7.3 x 101
. Relative to BaP
b Probahle human carcinogen
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TABLE 29
TOXICITY EQCIVALE:\CY FACTORS FOR
CHLORINATED DIBE:-';ZO-P-DIOXI:\S A..~T> -DlBE:-';ZOfl..,R.\..'S'
..,
( CompoUild ~ TEF I
Mono, Di, and TriCDDs  0
2,3,7,8-TCDD  l
ather TCDDs  0 
2,3,7,8 - PeCDD  0.5 
Other PeCDDs  0 
2,3,7,8 - HxCDD  0.1 
Other HxCDDs  0 
2,3,7,8.. HpCDD  0.01 
Other HpCDDs  0 
OCDD  0.001 
Mono, Di-, and TriCDFS  0 
2,3,7,8.. TCDF  0.1 
Other TCDFs  0 
1,2,3,7,8.. PeCDF  0.05 
2,3,4,7,8 - PeCDF  0.5 
Other PeCDFs  0 
2,3,7,8 - HxCDF  0.1 
Other HxCDFs  0 
2,3,7,8 - HpCDF  0.01 
Other HpCDFs  0 
OCDF  0.001 
a
EPA 1989b. Interim Procedures for Estimating Risks Associated with Exposures to MixtUres of
Chlorinated Dibenzo-p-Dioxins and Dibenzofurans (COOS and CDFs) and 1989 Update.
EP A/625/3-89/0 16.
718\MONT ANAIT A.8LES\6-2. TBL
01 f2B/9J ,...
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\IO~TASA POLE ROD - DECISIO~ St~L\L\RY
FIGURES
-------
. -.
i Figure 1: \
I Montana Pole Superfund Site!
Butte, Montana
, -
:- L-
~-
-
-.
~ -f', -:-----. ----...:. ---
-:. ~.r, - =-- ~ ----,-.
... . - '~ --::-'t
-'"'~ - ---.-1.<. -~ ~----
.{ --~lfutte..~i1t3Jia;-\ . --:
x-.r-J - ( '-- ~".: -o-
r r..,~) 1 )-';',3 '-i ;--:
L II l1:./ L--r - .
., I
~
~
~
I I
,
I I
I .
I ,
\ I ,(
I '
! '
, I I ~
, ,
~~~-1i~
------
- ... ---
-....
"
'--
o 1-
~ -
30lIO
45011
J No.: 93DHES:37A
Sc:a1e of Feet
Apn1 1m
-------
. ./
~\W
.1 il
~ Butte/Silver Bow Creek r .'PL Site
~
~ Lower Area One Operable Unit
-
EPA GrouridwateL
Treatment Plant -
, ' ~

I --";';.':'.
-:"I~""'-:"'.-
'8
J
..' ! ,II au) I
.
Olsmanded
equipment
storage """-
building -
WOOl,," po" storage ru:.1 fl
storage y.
I bUU~-
-
./
.
Eastern pole
storage yard
Site Layout and Features
FIgure 2: MontaDa Pole and Treat'" PIanL

- Buitc1ins
~ Water
~ Slas Wall
Montana 6tate Llbr
o ao 4(1) BJ)
~~-==
Scale in Feet
t-+-+-+i
(JD
tffi)
Paved Road
~
Railroad
Fence Line
J~9j
lie N~: 931)/1[5318
-------
. L#
'l'
/.::'.'
.:;'
/.::'.,
.:;'
/.::'.,
.:;'
/.::'.,
.:;'
/.::'.,
. :;'
......-::;".-
Cl8f/Jf;..-;;:-':'';-<'
. ~.-:;::..
S.,...8'..-:;::""
~..
-;,::.".".
~.."
.,~ .
.70- . ----t-t--'" , '
h' . una ~-- -.
,.,:;,' 51811 w.. "cllv. Ra".oa~.--------'-'
~ . ..--. ..0- . ~--t-,.-. .
'::;' ~-
Low.r AI.. One
Operable Unll
LEGEND
~ Mounl MOllllh

~ C_".
~ ~~:lln~~ ~:a~~~rIUnlstiC Samp~ . ;~~=~:n~ ~ ~;::~ad Tracks

Gr..I8Ilhan 15.000 I9kIl
IA Sur lace Waler Pattern Sample -*--* fence
181 Surface 5011 Sample location/Grid . Applollmal. A... 01 Site Boundary
Toial Palloh,um
'" Subsurface 5011 Boring location Hydloc..bons m Removed SOils
8 MomtUllng WelVSubsurlace Boring location G.8818rlhan 100 mgIkg 510rage Building

SII. F ...I'"..s 8S 01 1!189 Nola: A' ..mpling loclilions ..a .hown 00 Flilw. 2- \.
20Q --
400
1
o
[
SCALE IN FEET
, "
. .
. .
. . .
---
-- - .. --- ---_J"
::......
~
~: --
- --------
.-----
, ~ ' , .
- ."'"
MONfANA P<>I E ANI)
THEA TlNG PI AN I SII L
PCP AND TPH CONCENTRA TIONS
DETECTED IN SURFACE
SOIL SAMPLES

10'1( a Jlu.: .\
2 ""J )
---.-.---
-------
.~.
/-.'.,
.~
/-.'.'
/-..:.~
.7
.'l""
/-.'.,
.7
..~..,
r."'f...-:;::,"
-......... /- "
~~~.:,.....
.:.~'."~.'
GS2!)
.
Cone:.
lowor AI.. Ona
ap_ebIe U~
.
GS34
Depth Cone.
0-2' 3,160
8." 11,800
30.32' 114
165.000
47,500
8.600 SIeg Wall
.~~I-t-t-I-'-I-'-


GWI31A5
8
Deplh Cone. 
()'2' 38.900 
6-8' 91.601' 
  .
33.36' 73 
Depth
0-2'
4."
21.30'
Cone:.
131,000
13,500
<388
Depth Cone:.
().2' 108
2.6' 88.200.
6- 10' 4,140
to.14' 118
Depth Cone:.
14. I" <"3
18.22' <"5
22.26' 
-------
I U
Bont.mpo
lowe' A'.. One
0peI"- UnM
Slag Wall
~II~. f\a.,oad una
..-.-t-'. ,
..... ....-
,,'
,... It
,,~. .
,., ' ' ,.
.~.~
-i -.--"'-"- .
~ ~
"
B
._- --..--------
GWI:VAla
------------
-- _.--- .-...-.---f
n81
es
.-- - -----
-----_---/
polenllal
SludglllW.ll.
Dispolal
A'..
auoled ee- One I
'-Gw;'AW";;l~~ ':==.. l' ~~--
, S\oAIJ8 - -- -
GW27/A2e.~ ~b'
C 1.27 I . B8
I 61.25
GW281A24 m
I 4
I m
I w..18111
IT'MledWood m
6\01.1'8 Veld rTl
I . +
I 87 AI
I
I
I
~.-:.:.
-------
r
L_-
Eulern TI..led
Wood S\OI.ge Veld
'.' , , ,
- . -. ~ . f
85
.
G,eenwood \venue
.~.
.
Monllorlng WelllBoring locallon
Subsurlace Soil Boring locaUon
. SubslI,lace ~oU Boring Based
on 20% Surlace Soli Sampling
. MonllOilng Wen Ins'alled lor \he RVfS
A.A' CIUSS Secllon
    ~  Mounl MOllah 
  Railroad Tracks   CemelelY MONT ANA POLE ANI>
!-.-t-t-+   
-"-'" Creek    TREATING PI AN r SII t:
-'--...   
--M )C Fence    SUBSURFACE SOIL BORING
  Site Bounda'v    CROSS SECT IONS
CD Removed 50115 0 20Q 400  
  SIorage Building ~- I  ',I( ;I litE S
    SCAlE IN fEET  ..." 
lEGEND
~Iht ftwhUtt5 ,5 01 '989
-------
(NOIlh) A
..
~
..J
J f>430

I
I
j
~
5 f>420
i

UJ
l_-
A4
MR!!
f>460
f>450
!i440
¥
MIO
, ~,J
A14 A2
f>431.& -
A7
lli!.!!
A16 A21
~~
A19 A20 AIO
~ !i4!i82 !i4ti06]
I
Clayey Sand
6I1y Sand
CIa
Sand and
fine G.av"
Sand and
Fine a.av"
Clay
W..lh8led
Bedlock
SUI lace
Sand and
FIn.O.avel
I'
!i400 -
t>390
MONTANA POLE AND
TREATING PIAN I Slit:
PCP CONCENTRATION IN
SUSBSURFACE SOil BORING
CROSS SECTION A-A'
W..1h..ed B8d1ock
S",I8c:.
LEGEND
A4 SubsUJl8c:. Boling NUI.mel
5431.41 a.ound SurIac8 Elavalion
o If>O 300
f- ----I

HORIZONTAL SCALE IN FEET
I
Indlcal.a S&j)lUIlac. Bating
(ill]
PCP Concenlr.tion In I'glkg
MO.
A' (Soulh)
t>4tiO
t>4t>O
- t>44U
. M]U
. t>4~11
. t>41U
1,'1( a Jlu.: 6
-------
(Wesl)8 A12   
  ~   
 5440    
     Sill
     SIlly Clay
     Clay
  ~   
 5430    
   C18y  
   S~ly Sand  
     S80CIy O'aval
c;     
~ 5420 -    
J     
.     
..    Sill 
III    
c     
"     
..     
~    Clay 
II    
>     
&     
0(     
i     
~     
c     Sandv G,avel
Q    
~ 5410 - ,JU   
!!    
W     
Sandy Clay
W.alherad
Badlock
Swlau
5400 -
LEGEND
A 12 SlJbsw'aca Botlng Numbe'
~ G,ound Sullac. Elavallon
I
'ndlcale~ Subsu,lac. Botlng
Ei~1
PCP Concenll aUon IIIl'9'kg
~) t~U
*-- -- . ------
A13
~
<108
'I U
Silly Clay
S'ty/Clayay/Grava'
Clay
Sandy Graval
Wealhered
Bed,ock
Surlaca
o 5Q ------- 100
~ -I
HORIZONTAL SCALE IN FEET
A14
5431
A I ~ B' (East)
~~:!!,! ~~
---T' -- 5440
---- -
~:111 1~~eOOl

.--r
----- - G:~ ~I
Sand - -- - - ---I

I~~JI
T - 5430
118~1
I
I- 1191
- -:, -

I- II?I
~-----
Sendy Grav..1
~=-~-
5420
- CI~y









li¥) - ---- - -
I . 11.1
\ -

1.1191
,-
I- II-I
54111
~4Ull
MONT ANA POI E ANI)
THEA TING PI AN r Sill:
PCP CONCENTRATION IN
SUBSURFACE SOIL 80RING
CROSS SECTION 8-8'
1'1( a 11(1<: 7
-------
ILJ
5410
A27
~
A24
~
I
1.8 A21 1.9 B3
~~-~
82
UI
C' (I::asl)
(WeSI) C
5460
- 54bU
Sand
545U
5450
ClaY.Y Sand
~T
544U
81Ady a.av"
544.0
Clay
~. <3iJ.
1
...J

J 543~
c
I
~
j
i
!!:..
5no
<402
Sand and
fine G,aval
~ 5420
.
j
w
M20
w..\h8Iad Badlock
SUI lac.
5410
5400 LEGEND 
 A21 Subs",'a". BOling Numb.'
 ~ Glound SUilaca Elevallon
 I Indic:a"i Sub$wlac;a 80/U111
 IillJ pCP Concanbalionln 1'9'k9
~J!JO -  
o 15Q 300
I - )
HORIZONTAl SCALE IN FEET
MONT ANA 1'01 E ANI>
TREATING PL AN r 511 E
PCP CONCENTRATION IN
SUBSURFACE SOIL BORING
CROSS SECTION C-C'
1,'1( a Jim x
MOO
. --- ---
-------
~
ll\ilaiiiI--- . -
Mount
o~ah ~~ "t"y . .
-- ! ~ I.
--- - ---
----
---- ---
Montana Stata Libra
NaIw1I ~ bI(ooDaIima SyllaD
Figure 9: Surface water, groundwater, and LNAPL (Ooatlog oil) contamination

e'::;:':::::.1 Approximate BxteDt of Paved Road
PIoaUn& Oil Cuntamina1iOD . t I-f t
IIllllUIllID Approximate Bxteo1
of Groundwater and
Surface Water CoP1:an1ination
Railroad
~
II ~m UlO
~--~~-"'-~
Scale in Feet
ffi)
~J~:::-!
Tai1iogs pond
A ,iI I~~I
/("1 fJ... ~ II ./ltS 12/111;1
-------
, ;_1
ill
89-11
.
.'.1
81127.

ITJ
8112..

bJ
.
811-7
EEl
~
-t HONItOAING "ELL LOCATJOK
. AI MONITORING "ELL
BAOIlIIO I DATA I"g/ll
<, 0 ROUND 2 01.11. 1..0/11
- - ROUIIO 3 DATA l..gII\
MM APPROXIMATE HOUNT HORIAH "ELL LOCATION
R fiELD DUPLTCATE 1..0/11 Of CONCENTRATION LISTEO ABOVE
~IDI PCP 9CAEEtUNG COIICENTRUTOK 1..0/1\ KEYSTONE METHOD 688
IIOT SAMPLED
SCALE Ift:E 11
~--
o 200
400
_.-:/--,../
------/
~----
~ -----
-. ',._J - -

-- .::.~:---~-=L:r=:=:

=--~~~;_.,,~.-~-I T'
i
~
i
i
~
'~

"
Nj ".... ,-
.!!!!!!...--- -
111N1 __M COIl""
1111
liB
MONTANA POLE AND
TREATING PLAN r sn E
GROUNDWATER QUALITY MAP
OF ON-SITE AND NEAR OFF-SITE
WELLS - PCP
Fit a lit I': In
f&t.40 )
-...-----
-------
~

G5-26-+-
-+- N-1

bd
+- BMW-3A

~
BMW.5A+-

~
!~
LEGEND
.
.
-+-
Monllorlng Well Locallon
AI Monllorlng Well Locallon
01l-511e Monlloring Well LocaUon
~
GttJ
Round I coneentretion, I'g/\
Round 2 coneenl'ellon, 1'911
Round 3 concenlr elion, 1'911

Nol Samplod

PCP Sc...oning Method h.gII)
~ .uld O"phcoh. 01 P,evlous Concenllelion
.,
-----
-+- PW-GS.04

~
o
r--
135 270
--_... .-1
SCALE IN fEET
i ¥
[;'" -+- NE-2

<1.0
. < 1.0
-+- NE-1

~
t
g
GttJ
-+- GS-25
  ..
 o <1.0
. 0 <1.0
  ..
CT-84-6 -+-

~
~~~J

~+
GWI4.
- .
_....E.~ '-
,j 269
BMW-1B
-+-
~~
CjfJ
GW12/A12 .
lo~~1
MONTANA POLE AND
TREATING PLANT SITE
PCP CONCENTRATIONS DETECTED
IN GROUNDWATER SAMPLES
FROM ADDITIONAL OFF-SITE WELLS

FH;URE II
&lWJ MO
-------
+"'" 1- I
,o~:~
- 80nl8mpo
II
1/
i.
~
lower AI88 008
Operable Unit
<> 3.82
~~
GS34
Slag Wall
,. ,.1 ' ' ' .
",cIN. Railroad ~~-.-- .-t--...-.--t-<- .-t-
... .
. .
\ \
GS.7
0<'.0
.0<10
<2.241<>1.611*01.48
- .---
-----.----f
-------
..---_.-~
-
~
~
-:::.-
.'-. ---~---
-- - n- - - --
Q
, ~ I , , t f
Pole 5101ag8
Yald
Glaanwood Avenue
LEGEND
.+-
.
.
.+-
o

h~~-\


o
~
-
Mounl MOlieh
Cumulliry
MONT ANA POI E. ANI)
TREATING PLAN I SII E
Monitoring Well Locallon
Monitoring WelVSubsUltace Boring Location

OIl.Slte Monitoring Well Location
Seep
Hound 1 dale, I'gIl
Round 2 dala, 1'9'1
Hound 3 dala, I'gIl

PCP SCJeenlng Melhod (l'gII)
Fluid Ollpllcala 01 P/avlous Concentration
PCP Concentration ~ 10,000 ~g11
PCP Concenlrallon < 10,000 ~!YIand ~ 1,000 IJgll
PCP Concentration < 1,000 ~gIIand ~ 1.0 \Ig/I

t-I-t.-+-+ Railroad Tracks
=::=::: Creek
~ Fence
Site Boundary
Slle FualUles a5 a, 19119
No'e: AU 5ampUng locations 81e shown on Flgule 4.2.
~
ESTIMATED EXTENT OF PCP PLUME
o 200 400
[--- - -1
SCALE IN FEET
FHamE 12
1.10)
----------
l.
-------
.:;,...
" .
.~..
II
1/
\\-.
-.==::::
~ .-.-,-t -t-t-t--'--' ---.-t--'-
-~
Dele
Sempled

11/90
7/90
6/91
Dele
Sempled

11190
7/90
6/91
Dele
Sempled

11/90
7/90
6/91
LEGEND
¥
Monlloring Well Localion
Not Sampleu
\~~) blllllllted Extenl 01
I NAPL
~lHIlLti KttY~'Olltt, 19Q1
Thlckn...
(1..11
008
001
.,~'.,
.' --:/.,
.;:,,'
.~
.--:/'. .
.;:,'.'
c.\~.:7
ypi:.;:,':'~

TREATING PI AN I SII E
PRODUCT THICKNESS MEASURED
IN MONITORING WElLS
Mounl MOIlah
Cemela,v
Nole:
All sampling loclltlons IIle shown on Figure 2-1.
a
r .-.-
20Q -
~oo
'1
FuamE IJ
SCALE IN FEET
M') J
--- - ------
-------
: ~1
low.. A... On.
Op.. .ble Unil
COI\'all,h..... Round 1 ROII..d 2
PCPII.!r'I1 4.11 < 1.0
P.o.UII1WlI <20 <20
T PH (mgII) <0.1 .0 I
CUllloll,lnou. Round I Round:3
~hoWII 18.5 14.11
PAU hoWlI <2.0 <2.0
{PU (mg/l) <0.1 <0.1
-4-
, ------

SWOO4
l oceled .1
USGS Sledon
Round 1
5111
411.53
0.5113
Round 2
207
475
2.17
ContemNni Round 1
PCP (pgII) 2. 13
P.o... (IIQIII <2.0
TPU (mWl) ~
ConI.mI...nl
PCP
PAil (\lg!I)
TPII (mgIIl
'- SW()02
- . . - : : :::::": ~
'. :---.
,-,.
"~"
':---'
'-'.
':-"
'-'.
COlllemlnenl
Round 1
PCP holt'l 3.75
PAil (\l1t'1 .2.0
TPlt j;gII)- --;0,-
-----
101...1.185 15 & 110
.-------
lEGEND
t.
.
1I11I!J18111 508501181 Seep
I-.-.-t-.
Rall/oad flacks
Cleek
10 Malur Sellp
-..-.,.
_0._0.'
.
""IIHce wale/ sampling locallons
lur lloe 19!)O nl
Nole:
Seep observ8t1ons hom June III/ough Decembel 1990.
AU s8mpllng locetloris 81e shown on Flgu/e 2.2.
o 6C!.- !20 180

1_- ----_J
SCALE IN FEET
~)llu 1"01111.,.,5 as oilOti9
--.--.-------
, . :;f"'''' .
.-
o
K
...0
-uP
.. ~
~!
~i
i¥1
=-~-c
-----------
MONT ANA POI E ANII
TREA liNG PI AN I SII E
PCP, PAU AND TPtl
CONCENTAA TIONS DETECTED IN
SURFACE WArEn SAMPLES

FU;UIU: 1-1
..»
-.------.
-------
'l U
Contamlnanl Round:Z
 PCP (l'!J!kg) 333
, PAH hJ9llkg) 3,71
 .. PH (mglkg) 161
Lower A'8a One
Opelable Unil
--
.----

S0004
Locatad al
USGS Slallon
,-y-~
'r~-'.....-' ';a\\load L\J\8
-~-y"r- I-
~
tv10NTANA POlE AND
TREATING Pl.AN I SIII-,
PCP, PAH AND TPH
CONCENTRATIONS DETECTED IN
CREEK SEDIMENTS

Fl
-------
\ U
FIGUItI!: 16 : SOURCES OF CONTAMINATION FROM HISTORIC MPTP OPERATIONS, SITE MEDIA, TRANSPORT
PATHWAYS, AND lNAPl RECOVERY AND.,SEPARATED WATER INFilTRATION SYSTEMS
lNAPl
STORAGE
Sepa'aled Oil
INFll TRATION
GAllERIES
5epa'aled Wale,
OILJWATER
SEPARATORS
1I11111,ellon
GROUNDWATER
Pa.IIIIOIIlng
SUBSURFACE
SOilS
1I111111alloo
100III,alion
\  I
SURFACE
SOilS
 VolellUlallon and 
 Pailiculale T,anspo,l 
  AIR
Pumpll1IJ
Dlssolullon
Absorption
I

510111\ Wala,
Runo!!

\
RECOVERY
TRENCIIES
LNAPL
PLUME
SILVER BOW
CREEI( SURFACE
WATER
pa.lllloning
SIL VEn BOW
Cr~EEK SEDIMENT
-- - . ----.
----------.--..-------------. -
....,
-------
1r 1/ -,

Figure 17: Cont9mlnated Surface and Subsurface Soils

~ Contaminated Surface &: Paved Road
Subsurface Soils ,-H-t-.
I-:~---~I Cootam. Surface Soil Railroad
- Building
~ Water
~ sta Wall
-~-+--t4-+-~-"'--'-'-'----'
@@
.
, -- --
.
-------
~10~TA..~A POLE ROD .. DEClSlO~ St.~[\'l~Y
~
APPENDIX A
ARARS
-------
A'pP~~1)IX A
FINAL DETE.R:MrnATION AND DESCRIPTION OF
APPUCABLE OR RE.LEV ANT AND ~PROPRIATE REQUIREMENTS
MONTANA POLE & TREATING PLANT NPL SITE
BuTTE. MONTANA
* * *
sEPTEMBER 1993
* * *
-------
TABLE OF CONTS'ITS
Page
1.0 APPUCABLE OR RELEVANT AJ.'ID APPROPRlA TE REQUIREMS~lS

(ARARS) . . . . . . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . . . . ., 1

1.1 ARARS FOR REMEDIAL ACTIONS. . . . . . . . . . . . . . . . . . . . ., 1
1.2 REQUIREMENTS FOR ARARS . . . . . . . . . . . . . . . . . . . . . . . . .. 1
1.3 ARARS APPUCABLE TO THE MONTANA POLE NFL SITE . . . . ., 3
2.0 FEDER.AL ARARS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ., 4

2.1 FEDER.AL CONTAMINANT-SPECIFIC ARARs ..,.. ~ . . . . . . . ., 4
2.1.1 Safe Drinking Water Act (Relevant and Appropriate) ...,... 4
2.1. 2 Resource Conservation and Recovery Act (RCRA) . . . . . . . ., 7
2.1.2.1 . Groundwater Protection Standards (Applicable) ., .' 7
2.1.2.2 Hazardous Waste Management (Relevant and
Appropriate) ......................... 7
2.1.2.3 Land Disposal Restrictions. . . . . . . . . . . . . . . .' 8
Clean Air Act (Applicable) ....................... 9
2.1.3.1 Particulate Maner ........... . . . . . . . . . ., 9

2.1.3.2 I..ead.............................. 10

2.1.3.3 Asbestos............................ 10
2.1.4 Federal Insecticide, Fungicide, and Rodenticide Act
(Applicable) . . . . . ., . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.2 FEDERAL LOCATION-SPECIFIC ARARS . . . . . . . . . . . . . . . . . . . 10
2.2.1 Fish and Wildlife Coordination Act (Applicable) .......... 10
2.2.2 Floodplain Management Order (Applicable) ............. 11
2.2.3 Protection of Wetlands Order (Applicable) . . . . . . . . . . . . . . 11
2.2.4 Resource Conservation and Recovery Act (Applicable and
Relevant and Appropriate) . . . . . . . . . . . . . . . . . . . . . . . . 11
2.2.5 Endangered Species Act (Applicable) ....,.. . . . . . . . . . . 12
2.2.6 National Historic PreserVation Act (Applicable) . . . . . . . . . ., 12
2.2.7 Archaeological and Historic Preservation Act (Applicable) . . .' 13
2.2.8 Historic Sites, BUildings and Antiquities Act (Applicable) . . . .' 13
2.2.9 Migratory Bird Treaty Act of 1918, as amended (Applicable) ., 13
2.2.10 Bald Eagle ProteCtion Act of 1940, as amended (Applicable) . .' 14
2.3 FEDERAL ACTION-SPECIFIC AR.ARS . . . . . . . . . . . . . . . . . . . . . 14
2.3.1 Safe Drinking Water Act (Applicable) . . . . . . . . . . . . . . . . . 14
2.3.2 Resource Conservation and Recovery Act
(Applicable/Relevant and Appropriate) ................ 14 .
2.3.2.1 Criteria for Classification of Solid Waste Disposal
Facilities Practices (Applicable) . . . . . . . . . . . . . . 14
2.3.2.2 Standards APplicable to Transporters of Hazardous
Waste (Applicable) ..................... 15
2.1.3
-------
3.0 STATE OF MONTANA ARARS ............................... 19
3.1 MONTANA CONTAMINANT-SPECIFIC ARARS .............. 19
3. 1. 1 Water Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
3.1.1.1 Surface Water Quality Standards (Applicable) . . . ., 19
3.1.1.2 Montana Groundwater pollution Control System
(Applicable) . : . . . . . . . . . . . . . . .'. . . . . . . . . 21
3.2 MONTANA LOCATION-SPECIFIC ARARS . . . . . . . . . . . . . . . . . . 22
3.2.1 Floodplain and Floodway Management. . . . . . . . . . . . . . . . 22
3.2.1.1 Floodplain and Floodway Management Act
(Applicable or Relevant and Appropriate) . . . . . . . . 22
3.2.1.2 Floodplain Management Regulations (Applicable
or Relevant and Appropriate) ............... 22
3.2.1.3 Solid Waste Management Regulations (Applicable) . . 24
Natural Streambed and Land Preservation Standards
(Applicable) ................................ 24
3.3 MONTANA ACTION-SPECIFIC ARARS . . . . . . . . . . . . . . . . . . . . 25
3.3.1. Watef Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25
. 3.3.1.1 Groundwater Act (Applicable) .' " . . . . . .'. . . . . 25
3.3.1.2 Public Water Supply Regulations (Applicable) . . . . . 25

Air Quality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

3.3.2.1 Air Quality Regulations (Applicable) .......... 25
3.3.2.2 Reclamation and Revegetation Requirements
(Relevant and Appropriate) ................ 27

3.4 OTIiER LAWS. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

3.4.1 Groundwater Act ............................. 28
3.4.2 Water Rights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
3.4.3 Occupational Health Act . . . . . . . . . . . . . . . . . . . . . . . . . 29
3.4.4 Federal Occupational Health and Safety Act . . . . . . . . . . . . . 30
3.4.5 Montana Safety Act . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
3.4.6 Employee and Community Hazardous Chemical Information

Act. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
2.3.2.3 Standards for Owners and Operators of Hazardous
Waste Treatment, Storage, and Disposal Facilities
(Applicable) . . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.3.3 Hazardous Materials Transportation Act (Applicabie) ...,... 18
FEDERAL ST A,NDARDS TO BE CONSIDERED. . . . . . . . . . . . . . . 18
2.4.1 Federal Guidance Documents. . . . . . . . . . . . . . . . . . . . . . 18
.. -.
2.4
3.2.2
3.3.2
ii
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ARAR
A TSDR
BAT
BCT
BPCTCA
BPJ
CERCLA
DNRC
DSL
EPA
FIFRA
HWM
LNAPL
MCL
MCLG
MDHES
MGWPCS
MPDES
NCP
NESHAPS
NPL
NPDES
PAR
PCP
POHC
POTW
PSD
RCRA
RIlFS
ROD
SHPO
SIP
TBC
TU
mc
UST OF ACRONYMS
Applicable or Relevant and Appropriate Requirements
Agency of Toxic Substances and Disease Registry
Best Available Technology Economically Achievable
Best Conventional Pollutant COl'1trOl Technology
Best Practicable Control Technology Currently Available
Best Professional Judgment
Comprehensive Environmental Response, Compensation, and Liability Act of
1980
Department of Natural Resources and Conservation (Montana)
Department of State Lands (Montana)
U. S. Environmental Protection Agency
Federal Insecticide, Fungicide, and Rodenticide Act
Hazardous Waste Management
Light Non-aqueous Phase Liquid
Maximum Cont"minant Level
Maximum Contaminant Level Goal
Montana Department of Health and Environmental Sciences
Montana Groundwater pollution Conuol System
Montana Pollutant Discharge Elimination System
National Contingency Plan
National Emissions Standards for Hazardous Air Pollutants
National Priorities List
National Pollutant Discharge Elimination System
polynuclear Aromatic Hydrocarbon
Pentachlorophenol
Principal Organic Hazardous Constituents
Publicly Owned Treatment Works
Prevention of Significant Deterioration
Resource Conservation and Recovery Act
Remedial Investigation/Feasibility Study
Record of Decision
State Historic Preservation Officer (Montana)
State Implementation Plan
To Be Considered
Turbidity Unit
Underground Injection Control
ill
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1.0 APPUCABLE OR RELEVANT k'ID APPROPRIATE REQUIRE!vlL'ITS (ARARS)
1.1
A.RARS FOR REMEDIAL ACTIONS
Section 121(d)(2) of CERCLA, 42 V.S.C. g 9621(d)(2), requires that cleanup actions
conducted under CERCLA achieve a level or standard of control which at least attains "any
standard, requirement, criteria or limitation under any Federal environmental law ... or any
[more stringent] promulgated standard, requirement, criteria ur limitation under a State
environmental or facility :;iting law .,. [which] is legally applicable to the hazardous
substance concerned or is relevant and appropriate under the circumstances of the release of
such hazardous substance or pollutant, or contaminant..." The standards, requirements,
criteria or limitations identified pursuant to this section are commonly referred to as
"applicable or relevant and appropriate requirements," or ARARs.
The remedy for the Montana Pole & Treating Plant NFL site must comply with or attain all
ARARs unless specific ARAR waivers are invoked. ~ CERCLA ~ 121(d)(4), 42 U.S.C. 9
9621(d)(4), and the NCP, 40 CFR 300.430(f)(l)(ii)(C). ARARs must be observed both
during the conduct of on site clean up activities and at the conclusion of the cleanup activity,
unless specifically exempted. 1
1.2
REQUIREMENTS FOR ARARS
A.RAR.s may be either "applicable" requirements or "relevant and appropriate" requirements.
Compliance with both is equally mandatory under CERCLA.1
Applicable requirements are those standards, requirements, criteria or limitations
promulgated under federal environmental or state environmental or facility siting laws that
specifically address a hazardous substance, pollutant, contaminant, remedial action, location,
or other circumstance found at a CERCLA site.
Relevant and appropriate requirements are those standards, standards, requirements, criteria
or limitations promulgated under federal environmental or ~(.3.te environmental or facility
siting laws that, while not "applicable" to hazardous substances, pollutants, contaminants,
remedial actions, locations, or other circumstances at a CERCLA site, address problems or
situations sufficiently similar to those encountered at the CERCLA site that their use is well
suited to the particular site. FactOrs which may be considered in making this determination,
when the factors are pertinent, are presented in 40 CFR ~ 300.400(g)(2). They include,
among other considerations, examination of: the purpose of the requirement and the purpose
of the CERCLA action; the medium and substances regulated by the requirement and the
medium and substances at the CERCLA site; the actions or activities regulated by the
requirement and the remedial action contemplated at the site; and the potential use of
40 CFR ~ 300.435(b)(2); Preamble 10 the proposed NCP. 53 Fed. Reg. 51440 (December 21. 19&&); Preamble 10 the Final
NCP. 55 Fed. Reg. &755-&757 (MardiS. 1990).
~ CERCL.A t 12I{d)(2)(A), 42 U.S.C. t 962I(d)(2)(A).
1
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resources affected by the requirement and the use or potential use of the affected resource It
the CERCLA site.
.~ are divided into contaminant-specific, location-speciflc and action-specific
requirements. Contaminant-specific requirements govern the release to the environment of
materials possessing certain chemical or physical characteristics or containing specific
chf..mical compounds. Contaminant-specific AR.Alts generally set human or environmental
risk-based criteria and protocol which, when applied to site-specific conditions, result in the
establishment of numerical action values. These vJlues establish the acceptable amount or
concentration of a chemical that may be found in, or discharged to, the ambient environment.
Location-specific ARARs relate to the geographic or physical position of the site, rather than
to the nature of site contaminants. These ARARsplace restrictions on the concentration of
hazardous substances or the conduct of cleanup activities due to their location in the
environment.
-or
Action-specific ARARs are usually technology- or activity-based requirements, or are
limitations on actions taken with respect to hazardous substances. A particular remedial
activity will trigger an action-specific AR.AR. Un1ike chemical-specific and location-specific
ARARs, action-specific AR.ARs do not, in themselves, determine the remedial alternative.
Rather, action-specific AR.ARs indicate how the selected remedy must be achieved.
Only tbe substantive portions of the requirements are ARARs.3 Administrative requirements
are not ARARs and thus do not apply to actions cooducted entirely on-site. Administrative
requirements. are those which involve consultatio~ issuance of permits, documentation,
reporting, recordkeeping, and enforcement. The CERCLA program has its own set of
administrative procedures which assure proper implementation of CERCLA. The application
of additional or conflicting administrative requirements could result in delay or confusion..
Provisions of statutes or regulations which contain ~neral goals that merely express
legislative intent about desired outcomes or conditions but are non-binding are not ARAR5. s
Only those state standards that are identified in a timely manner and are more stringent than
federal requirements may be applicable or relevant and appropriate. To be an ARAR, a state
standard must be .promulgated," which means that the standards are of general applicability
and are legally enforceable.6
Additional documents may be identified as To Be Considered (TBCs). The TBC category
consists of advisories, criteria, or guidance that were developed by EPA, other federal
40 CFR '300.5 (Definitiolll of" "flfllicable requiremeou" aDd """ant and aflflfOllriate requiremenu.") See also Preamble to
the Final NCP. 55 Fed. Reg. &756-&757 (March &. 1990).
Preamble 10 the Final NCP. 55 Fed. Reg. &756-8757 (March &. 1990); Comflliance with Other LAw. Manual. Vol. I. Pfl. I-II
through 1-12.
Pt-eamble to the Final NCP. 55 Fed. Reg. &746 (March &. 1990).
40 C.F.R. ~ 300.400(j)(4).
2
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~-----------
-- --- - -----
agencies. or states that may be useful in developing CERCLA remedies. These may be
considered as appropriate in selecting and developing cleanup actions'-
1.3
.~RARS APPUCABLE TO DiE ~!O!\.~.-\.~A POLE ~-PL SITE
This document constitUtes 1-IDHES' and EPA' s fInal detennination and detailed description
of ARARs for remedial action at the Montana Pole NFL site. The descriptions which follow
include summaries of the legal requirements which are provided to allow the user a
reasonabl~ understanding of the requirements without having to refer constantly back to the
statUte or regulation itself. However, in the event of any inconsistency between the law and
the summary provided in this document, the applicable or relevant and appropriate
requirement is ultimately the requirement as set out in the law, rather than any paraphrase of
the law provided here.
::::
The ARARs analysis is based on section 121(d) of CERCLA, 42 U.S.C. 99621(d);
"CERCLA Compliance with Other Laws Manual, Volume I," OSWER Dir. 9234.1-01
(August 8, 1988); "CERCLA Compliance with Other Laws Manual, Volume II," OSWER
Die. 9234.1-02 (August, 1989); the Compendium of CERCLA ARARs Fact Sheets and
Directives, OSWER Dir. 9347.3-15 (October 1991); the Preamble to the Proposed National
Contingency Plan, 53 Fed. Reg. 51394, et. ~. (December 21, 1988); the Preamble to the
Final National Contingency Plan, 55 Fed. Reg. 8666-8813 (March 8, 1990); and the Final
National Contingency Plan, 40 CPR Part 300 (55 Fed. Reg. 8813-8865, March 8, 1990)
(hereinafter referred to as "the NCP").
~ C.F.R. ~ 300.400(g)(3); ~ C.F.R. ~ 300.415(i); PT'e.lmble 10 the Final NCP. 55 Fed. Reg. 8744-8746 (March 8. 1990).
J
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... -.
2.0 FEDERAL ARARS
Potential Federal applicable or relevant and appropriate r-:quiremcntS for the ~lontana Pole
~l'L site are discussed below.
2.1
FEDERAL CONTA..\-lli~A1~"'-SPECIFIC ARARS
2.1.1
Safe Drinking Water Act (Relevant and Appropriate)
The National Primary and Secondary Drinking Water Standards (40 CFR PartS 141, 14.3),
better known as "maximum contaminant levels" (MCLs), are not applicable to remedial
activities at the site because the aquifer underlying the site is not a public water supply.
These standards may be applicable in the future should the EP A detect an exceedance at a
public water outlet.
These drinking water standards are, however, relevant and appropriate because there is
groundwater in the area which is a potential source of drinking water and because the aquifer
feeds Silver Bow Creek, which is a potential drinking water source. The determination that
the drinking water standards are relevant and appropriate at the site is fully supported by
EP A regulations and guidance. The Preamble to the National Contingency Plan (NCP)
clearly states the MCLs are relevant and appropriate for groundwater that is a current or
potential source of drinking water, 55 Fed. Reg. 8750 (March 8, 1990), and this
detennination is further supported by requirements in the RIlFS section of the NCP, 40 CFR
9 300.430(e)(2)(i)(B). EPA's Guidance on RemeCial Action For Contaminated Groundw:J.ter
at Superfund Sites states that "MCLs developed under the Safe Drinking warer Acr geneially
are ARARs for current or potential drinking water sources" .
Certain institutional controls may be implemented by the agreement of Butte/Silver Bow
County government and some of the PRPs. If such controls are implemented to prevent the
use of groundwater at the site as a drinking water soorce, the need to comply with MCLs
throughout groundwater plumes at the site may ~ obviated. Thus, if sufficient institUtional
controls are implemented to prevent the use of groundwater at the site as a drinking water
source, the point of compliance for the MCL AR.ARs will be the boundary of the waste
management unit at the site, as discussed in the ROD.
The MCLs are relevant and appropriate standaI'ds for the remedial action to be conducted at
this site. In addition, the non-zero maximum contaminant level goals (MCLGs) are relevant
and appropriate (55 Fed. Reg. 8750-8752 (March 8. 1990». The points of compliance for
these standards are described in the ROD. The time for compliance is as soon as feasible,
and consistent compliance is necessary for completiOD of remedial action. Once achieved,
standards must be maintained.
:1
4
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.. -.
The ~ICLs and the MCLGs are:!
Chemical :.-ICLG (mg'l) ~lCL Img 1)
Inorganics:   
Arsenic N.A. .059 
Cadmium .00510 .00511 
Chromium N.A.12 .0513 
Copper 1.314 1.315 
Lead N.A.16 .01517 
EPA ba. rranted to th. Slate of Monlana primacy io enforca- of lb. Safe Drinkin, Wal8l' Ac:t. Thu. die law commonly
enforced in MOnl8na i. the IZate law, rather IiwI the federal law. However. since the federal MCu are al80 ARA!U for thll sile,
the more MnpnI of lb. federal or lUte IZandard. ia the relevanlllandard for each subllance.
40 CFR 1 141.11; ARM 16.:0.::03.
..
40 CFR 1 14l.S1.
II
40 CFR 1 141.51. The CUlTenl stale MCL. is less stringenllt 0.010 -g/l C;..e ARM 16.::0.::03.
..
The cbromium MCL.Ci, 11.1 mg/l. !!! 40 CFR 1 141.51. il n011l slri0lenlu Ibe Slate MCL. for Chromium. See foolDote 13
below.
"
ARM 16.:0.:03. The recently revised federal MCL. for cbromium. .1 mill. ~ 40 CFR t 141.62. i. less slringenl than the
CUrT8ll111ate MCL..
"
40 CFR , 141.51.
"
Thill."eI i. ao .Iction l."eI. similar to die lead 1.".1 dac:ribed in fooInoc. 17 below. ~ 40 CFR Subpart I (I 141.80(c)(2».
ID addilioll. a I8COndal)' MCL. of 1.0 mgll i. ideDlified for copp8l' at 40 CFR 1143.3. How"'8I'.lbe secondal)' MCLs are nOI
enforceable II federal IZandard. aDd are provided only a. guid.liDu for the statu. 111- IWIdarda are nOl generlilly considered
ARAR.s unleulbe state adopla Ibem.. enforceable standarda. ~ CERCLA CompliaDce With Other Law. Manu&!. Volume I
(AulUlt 1988), p. ~8. Monlana ba. DOlldopted Ibe sacoodal)' MCu a. enforceable suodard..
"
Lead is Imonl the aculely toxic substances for which the MCL.G is zero. ~ 40 CFR t 141.51. Howe'~r. the zero MCL.Cis are
not generally considered .Ipproprilte. requiremenu for CERCL.A cleanup.. primariiy for reasons of practicability. Se. 40 CFR
! 300.430(e)(2)(i)(C); see Iiso Preamble to the Final /'ICP. 55 Fed. Reg. 87S0-87S31M1rch 8. 1990).
"
40 CFR 1 141.80(c)(l). The level specified is nOlln MCL.. bUI rather 10 .Iction level.. The standard is nonnilly measured It
the taps of use~ of the ~'ater to accounl for additional lead contamination resulting from cOrTOsion io the "'ater supply lines. See
40 CFR Subplrt I, (40 CFR U 141.80-141.91).
5
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Organics:  
Benzene ~.A.iS 0.005~9
Dichlorobenzene (para) 0.075:0 0.075:1
Dichlorobenzene (ortho) 0.6 0.6
Ethylbenzene 0.7 0.7
~onochlorobenzene 0.1 0.1
Toluene 1. 1.
Xylenes (total) 10. 10.
Pentachlorophenol N.A.n 0.00123
Benzo(a)pyrene N.A. 0.000224
..>  
2,3,7,8-TCDD (Dioxin) N.A. 3. x 10.8
~CLs also fonn the basis for certain discharge standards and instream standards for surface
water, wben those standards are more Stringent than water quality criteria or state water
quality standards. Where this is the case, those standards are identified in Tables 26, Surface
Water Cleanup Levels and Corresponding Risks, and 27, Discharge to Surface Water
Cleanup Levels and Corresponding Risks, of the ROD.
II
The MCLG for ~ it %81'0. ~ 40 CFtl t 141.50.
..
40 CFtl t 141.61; ARM 16.2O.204(:1)(e).
,.
40 CFtl t 141.50.
"
40 CFtl ! 141.61; ARM 16.20.204(:1)(t).
,.
.$0 CFtl ! 14l.S0(a).
:J
40 Cn. ! 141.61.
MCl..o for Bcn%o(a)pyreneand Z.3.7.8-TCDD (Dioxin) were finalized July 17.1992. It 57 Fed. Reg. 31846. These SI£1\d.ards
become effective January 17. ,.994. However. as promulgated MCl..o they are still relevant Ind Ippropriate standards. The
MCLG for both of Ibese compounds is zero. and accordingly is not considered an appropriate standard.
..
6
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-~~- ---~
-._-------------_.._--~--- ---
1.1.1
Resource Conservation and Recovery Act rRCR-\)
2.1.2.1
Groundwater Protection Standards (Applicable)
{}nder ..W CFR Part 26.+. Subpart F:.s. concentration limits are set for hazardous constiruents
in groundwater. These standards are applicable to remedial actions at the site. The limits
spe..:ified for groundwater protection are the same as or less stringent than the ~ICLs or
MCLGs identified above for those substances.:6
2.1.2.2
Hazardous Waste Management (Relevant and Appropriate)
The Resource Conservation and Recovery Act of 1980,42 U.S.C. 9 6901, et~, and
accompanying regulations set forch the standards for hazardous waste. The EPA has stated
that the test for detennining whether such standards are applicable to cleanups at superfund
sites is:
::i
RCRA Subtitle C requirements for the treatment, storage, or disposal of
hazardous waste will be applicable if a combination of the following
requirements are met: a) the waste is listed or ~haracteristic waste under
RCRA; and b) either (1) the waste was treated, stored, or disposed of after the
effective date of the RCRA requirements (November 8, 1980); or (2) the
activity at the CERCLA site constitUtes treatment, storage or disposal as
defIned under RCRA. (42 U. S. C. 9 6901, et ~
Because of the location of the Montana Pole site, and the historical mining activities which
took place in this area, contaminated soil materials being addressed at the site may include
material derived during the extraction and benefIciation processes. Wastes from ore
extraction and benefIciation are specifically excluded from Subtitle C under the mining waste
(Bevill) exclusion, (RCRA Section 3001(b)(3)(A)(ii). Therefore, RCRA is probably not
applicable to mine waste found at the site. Process waste, which is not excluded by the
Bevill exclusion, may also be present at the site; no determination on that issue is made in
this ROD.
Despite this sitUation, the EPA has determined that certain RCRA standards, and their state
counterparts, are relevant and appropriate to potential remedial actions planned. The EP A's
determination is based on the current definition of "relevant and appropriate" found in the
most recent version of the NCP at 40 CPR ~ 300.5. For mining waste, cenain provisions of
RCRA can be relevant and appropriate if they meet the defInition of "relevant and
appropriate" found in the NCP; if the activities contemplated at the Montana Pole site will
result in discrete areas of mining waste which resemble traditional RCRA management units;
:J
The State of Montac.. implements an aulhonzed RCRA program which includes Ihe groundwater protection Llndards of .w CFR.
Pan 264. Subpan F. (1990) IS incorporated by reierence ill ARM 16.44.702.
:.0
The ma,umum groundwater concentrations specified are (1) for I~C ond lead: the Slme as Ihe MCL. .05 mgi!; !:) for
cadmium: Ihe ...me IS tile old MCL. .010 mgll. but not as Slringet& IS Ihe new MCL or Ihe MCLG. .005 mg/I. No solid waste
groundwater SI.IIndard is specified for copper.
7
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and if the mining waStes are located in areas wbere exposure is likely to occur. are tocatlons dIroUgbout the site. Land dlsposa1
restrictions (LDRs) may be applicable to site soils amtaminated with F032 and F034 waste
if placement of those soils occurs.
Land Disposal Restrictions
LDRs typically set concenmtion levels or treatment standards that hazardous wastes must
meet before they can be land disposed. These treatment standards represent best
demonstrated available treatment technology (BDA!) for these wastes. In some cases,
however, hazardous wastes and appropriate treatmCllt levels may differ significantly evc:n
witbin the same class of hazardous waste. See 40 crR ! 268.44. Consequently, a variance
8
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--~-----
---- -
-- ------ -- ---------------~---
c -.
from an LDR treatment standard may be appropriare when a Waste "differs significantly from
waste analyzed in developing the treatment standard." ~O CFR ~9 268.44(a) and (h). The
Corrective Action ~lanagement Units (CAMU) rule. see 58 Fed. Reg. 8658 (February 16,
1993). provides that remediation wastes from anyv.:bere at a facility or from releases outside
of the facility can be plac~d into either a corrective action manag~ment unit or a temporary
unit without triggering land disposal restrictions and minimum technology requiremenrs.
Therefore, with regard to the placement of F03: and F03.+ wastes at the site, the c.~vn; rule
is applicable. Thus, wastes which are excavated ('.an be placed in treatment units in
compliance with RCR~ requirements, even if the wastes are at levels above land ban
standards.
2.1..i
Clean Air Act (Applicable)
-
,
Section 109 of the Clean Air Act, 42 U. S. C. g 7409, and implementing regulations found at
40 CPR Part 50 set national primary and secondary ambient air quality standards. 27
National primary ambient air quality standards define levels of air quality which are
necessary, with an adequate margin of safety, to protect the public health. National
secondary ambient air quality standards defme levels of air quality which are necessary to
protect the public welfare from any known or anticipated adverse effects of a pollutant. The
ambient air quality standards and other standards set out below are applicable for releases
into the air resulting from remedial action.2& These standards must be met both during the
design and implementation phases of the remedial action.
2.1.3.1
Particulate Matter
The ambient air quality standard for particulate maneI' of less than or equal to 10
micrometers in diameter (PM-1O) is 150 micrograms per cubic meter, 24 hour average
concentration; 50 micrograms per cubic meter, annual arithmetic mean. 40 CPR 9 50.&9
(Applicable) .
In addition, state law provides an ambient air quality standard for settled particulate matter.
Particulate matter concentrations in the ambient air shall not exceed the following 30-day
average: 10 grams per square meter. ARM 9 16.8.818 (Applicable).
The Butte area has been designated by EP A as non-attainment for total suspended
particulates. 40 CPR ~ 81.327. ARM 16.8.1401 (Applicable) requires that any new source
:!
The ambiem air qualiry standard. eaubliaboia. pan of Mo_'. approved Sw.e Implemenution Plaa in many cases provide
Inore striageDl or addilioaal staadarda. Moreover, Ibe federa! ~ona apply Ibe suadard. oaly to 'major sourc.,;" the sUte
regulariona a,. tUUy applicable throulhout lb. stale aad .... DOt Limired to "-;or saurc.,." See ARM 16.8.808 IJId 16.8.811 .
821. As pan of an EPA-approved Sute Implemenution Plan. me Slale suadatds are also federally enforceable. Thus. the sule
sundards are identified in this section logetber with the iedera! SUDd.rds.
::.0
Ambient ait quality sundards are also provided for carilon moooxide. hyd""oo sulfide. nilrogen dioxide. sulfur dioxide. and
ozone. [f emissions of these compounds were 10 occur 51 the site in conn~oll ""ilb any remedial action. these standards would
also be applicable. See ARM 16.8.311 - 8:0.
"
The stlte air quality regulalions provide an equivalent suodard. ~ ARM 16..!.~1. which is eniorce.able in ManUM as p.-t oi
the SUte Implemenulion Plan.
9
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of airborne particulate matter that has tbe potential to emit less than 100 tons per year of
particulates shall apply best available control technology (BACT); any new source of
airborne particulate matter that has the potential to emit more than 100 tons per year or
particulates shall apply lowest achievable emission rate (LAER). The BACT and LA.ER
standards are defined in :\R.\{ 16.8.1401.
2.1.3.2
Lead
ARM 9 16.8.815 (Applicable). Lead concentrauons in the ambient air shall not exceed the
following 90-day average (annual arithmeuc mean): 1.5 micrograms Pb per cubic meter of
air. 40 CFR 9 50.1230 (Applicable).
2.1.3.3
Asbestos
The National Emission Standards for Hazardous Air Pollutants (40 CFR Part 61) designate
cenain air pollutants that cause serious adverse health effects. Subpart M (99 61.141-157)
specifies control requirements for asbestos. 40 CFR 99 61.145 and 61.150 (Applicable)
cover demolition and waste disposal for demolition operations and would be applicable if
asbestoS is encountered during implementation of the remedy.
--
2.1.4
Federal Insecticide, Fungicide, and Rodenticide Act (Applicable)
This statute (7 U.S.C. ~ 136 et ~.) regulates the sale, distribution and use of all pesticide
products in the United StateS and is applicable to any alternative inv.olving the recycling and
reuse of pentachlorophenol and other wood-treating pesticides. Under FIFRA, use of a
registered pesticide product in a manner inconsistent with its labeling is a violation of the Act
(7 U.S.C. ~ 136j). Recovered pesticides may be reused provided they meet new product
labelling specifications, which include concentration limits for pesticides in solution.
2.2
FEDERAL LOCATION-SPECIFIC ARARS
2.2.1
Fish and Wildlife Coordination Act (Applicable)
This standard (16 USC ~~ 1531-1566, 40 CFR ~ 6.302(g)) requires that federal agencies or
federally funded or authorized projects ensure tbat any modification of any stream or other
water body affected by any action authorized or funded by the federal agency provide for
adequate protection of fisl1 and wildlife resources. Compliance with this A.RAR requires
EPA and MDHES to consult with the U.S. Fish and Wildlife Service and the Wildlife
Resources Agency of the affected State. Further consultation will occur during the remedial
design process and specific mitigative measures may be identified in consultation with the
appropriate agencies.
..
The s\.Ote lir quality regulations provide In equlvllent standard. ~ ARM 16.8.815. ....nien is enfor.:eable in Mon\.O"" IS plrt "r'
the State Implemen\.Onon Plln.
10
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2.2.2
Floodplain Management Order (Applicable)
This requirement (40 CFR Part 6, Appendi..x A, Executive Order No. 11.988) mandates that
federally-funded or authorized actions within the 100 year floodplain avoid. to the maximum
extent possible, adverse impacts associated with development of a floodplain. Compliance
with this requirement is detailed in EPA's August 6, 1985 "Policy on Floodplains and
Wetlands Assessments for CERCLA Actions. II Specific measures to minimize adverse
impacts may be identified following consultation with the appropriate agencies.
If the remedial action is found to potentially affect the floodplain, the following information
will be produced: a Statement of Findings which will set forth the reasons why the proposed
action must be located in or affect the floodplain; a description of significant facts considered
in making the decisions to locate in or affect the floodplain or wetlands including alternative
sites or actions; a statement indicating whether the selected action confonns to .:.pplicable
state or local floodplain protection standards; a description of the steps to be taken to design
or modify the proposed action to minimize potential hann to or within the floodplain; and a
statement indicating how the proposed action affects the natural or beneficial values of the
floodplain.
-
2.2.3
Protection of Wetlands Order (Applicable)
This requirement (40 CPR Part 6, Appendix A, Executive Order No. 11 ,990) mandates that
federal agencies and PRPs avoid, to the extent possible, the adverse impacts associated with
the destruction or loss of wetlands and to avoid support of new construction in wetlands if a
practicable alternative exists. Section 404(b)(1), 33 U.S.C. ~ 1344(b)(1), also prohibits the
discharge of dredged or fill material into waters of the United States. Together, these
requirements create a II no net loss II of wetlands standard.
In order to comply with this ARAR, EPA and MDHES will consult with the U.S. Anny
Corps of Engineers (COE) or the U.S. Fish and Wildlife Service to detennine whether
wetlands exist at the site and, if present, what category of wetland they represent.
Compliance will be addressed by assessment of existing wetlands at the site, followed by
replacement of any wetlands destroyed by the remedial action.
2.2.4
Resource Conservation and Recovery Act (Applicable and Relevant and
Appropriate)
The'requirements set forth at 40 CFR ~ 264. 18(a) and (byl provide that (a) any hazardous
waste facility must not be located within 61 meters (200 feet) of a fault (see Appendix VI of
Part 264), and (b) any hazardous waste facility within the 100 year floodplain must be
designed, constructed, operated and maintained to avoid washout. Any discrete disposal or
storage facilities which remain on-site as part of remedial activities must meet these
standards.
II
These requirements are applicable through their incorporation by reference in Montsna. s regulations for its authonzed RCRA
program. ARM 16.44.702. .
11
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2.2.5
This starute and implementing regulations (16 USC ~9 1531-1543,50 CFR 9 402, 40 CFR ~
6.302(h)) require that any federal activity or federally authorized activity may not jeopardize
the continued existence of any threatened or endangered species or destroy or adversely
modify a critical habitat.
Endangered Species Act (Applicable)
Compliance with tbis requirement involves consultalion between EPA and the U.S. Fish and
Wildlife Service, resulting in a detennination as to whether there are listed or proposed
species or critical hahitats present on the site, and, if so, whether any proposed activities will
impact such wildlife or habitat. At this time, the U.S. Fish and Wildlife Service has not
identified any threatened or endangered species or critical habitat on the site. Therefore, no
further activities are required by this ARAR. .
2.2.6
National Historic Preservation Act (Applicable)
~
This statute and implementing regulations (16 U.S.C. ~ 470, 40 CPR ~ 6.310(b), 36 CPR
Part 800), require federal agencies or federal projectS to take into account the effect of any
federally-assisted undertaking or licensing on any district, site, building, strUcture or object
that is included in, or eligible for, the Register of Historic Places. To comply with this
ARAR, EPA and MDHES may consult the State Historic Preservation Officer (SHPO), who
can assist in identifying cultUral resources and assessing whether proposed cleanup actions
will impact the resources. If remedial action is likdy to have an adverse effect on any
. cultural resources whicb are on or neat the site, EPA and MDHES must examine whether
feasible alternatives exist that would avoid such efm;tS. If effects cannot reasonably be
avoided, measures should be implemented to {J1inimize or mitigate the potential effect.
NHP A regulations reserve formal determination of eligibility for the National Register of
Historic Places and "no adverse effects" determinations for Federal agencies. The EPA is
using the Cultural Resource Inventory for the Montana Pole and Treating Plant NPL Site
completed by ARCO and supplementing this with site-specific historical inventory and
adverse effectS determinations. The EP A will conrinue to consult with the SHPO to identify
specific mitigative measures, if necessary.
Research intO the Montana Pole and Treating Plant revealed that the facility began operatio11S
in July 1946 and remained in husineSS until May 11, 1984 (Camp, 1)teSSer, & McKee 1990).
Subsequent salvage and cleanup operations conducted by the EPA on the site removed most
of the plant's facilities. The area was surveyed for prehistoric cultural remains but due to
the disturbed condition of the site area, the potential for the existence of sucb materials is
minimal and none have been observed. In addition, the plant is less than 50 years old and
tberefore it does not qualify as a historic site. No further cultural resource inventory or
evaluation has been conducted on the site.
In April 1992, ARCO, EPA, MDHES, the Advisory Council on Historic Preservation, the
State Historic Preservation Officer, and the local governmentS of Bune/Silver Bow,
Anaconda/Deer Lodge, and Walkerville entered inoo a Programmatic Agreement to ensure
the consideration of cultural and historic values in a systematic and comprehensive manner
12
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---~..- --_n___-
throughout the Clark Fork Basin in connection with remedial action at the four Clark Fork
Superfund sites. This Programmatic Agreement may provide additional consideration of the
factors to be addressed under the National Historic Preservation Act, and the other rn:o
cultural resources statutes that are AR~. the Archaeological and HistOric Preservation Act
and the Historic Sites. Buildings and Amiquities Act, discussed below.
2.2.7
Archaeological and Historic Preservation Act (Applicable)
This statute and implementing regulations (16 V.S.C. g 469, 40 CFR g 6.301(c» establish
requirements for the evaluation and preservation of historical and archaeological data, which
may be destroyed through alteration of terrain as a result of federal construction project or a
federnlly licensed activity or program. This requires the EPA or the PRP to survey the site
for covered scientific, prehistorical or archaeological artifacts. The results of this survey will
be reflected and documented in the administrative record. As noted above, that survey
revealed no covered artifacts. Nevertheless, preservation of appropriate data concerning the
artifacts is hereby identified as an ARAR requirement, to be completed during the
implementation of this remedial action, if any covered artifacts are discovered.
2.2.8
Historic Sites, Buildings and Antiquities Act (Applicable)
~
-'
This requirement (16 U.S.C. ~ 461 et ~; 40 CFR ~ 6.301(a» states that "[i]n conducting
an environmental review of a proposed EP A action, the responsible official shall consider the
existence and location of natural landmarks using infonnation provided by the National Park
Service pursuant to 36 CFR i 62.6(d) to avoid undesirable impacts upon such landmarks."
"National naturalland'11arks" are defIned under 36 CFR i 62.2 as:
[A]rea(s) of national significance located within [the U.S.] that conIains(s) an
outstanding representative example(s) of the nation's natural heritage, including
terrestrial communities, aquatic communities, landfonns, geological features,
habitats of natural plant and animal species, or fossil evidence of development
of life on earth.
Under the Historic Sites Act of 1935, the Secretary of the Interior is authorized to designate
areas as National Natural Landmarks for listing on the National Registry of Natural
Landmarks. To date no such landmarks are identified in the area. Therefore, no further
actions are necessary to comply with this requirement.
2.2.9
Migratory Bird Treaty Act of 1918, as amended (Applicable)
This requirement (16 U. S. C. g 9 703 et seq.) establishes a federal responsibility for the
protection of the international migratory bird resource and requires continued consultation
w itb tbe U. S. Fish and Wildlife Service during remedial design and remedial construction to
ensure that the cle3.JJup of the site does not impact migratory birds. Spc: :ific mitigative
measures may be identified for compliance with this requirement.
13
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-- .-.- -- ---~-
2.2.10
Bald Eagle Protection Act of 1940, as amended (Applicable)
This requirement (16 U. S. C. ~ 9 668 et sea.) establishes a federal responsibiliry for
prOtection of the bald and golden eagle and requires continued consultation with the \]. S.
Fish .and Wildlife Service during remedial design and remedial construction to ensure that the
cleanup of the site does not adversely affect the bald and golden eagle. To date, bald and
golden eagles have not been identified at the site. Accordingly, no further actions are
required for compliance with this requirement, unless bald or golden eagles are identified.
2.3
FEDERAL ACTION-SPECIFIC AR.ARS
2.3.1
Safe Drinking Water Act (Applicable)
:l
The underground injection control (UIC) program requirements found at 40 CFR Part 144
would be applicable for alternatives that involve reinjection of pumped and treated
groundwater. The progI3JIl divides wells into five classes for pennitting purposes. Class I
wells are used to inject hazardous waste or fluids beneath the lower-most formation
containing, within one-quarter mile, an underground source of drinking water. Class IV
wells are used to dispose of hazardous waste into or above a formation which contains,
within one-quarter mile of the well, an underground source of drinking water. Class IV
wells are generally prohibited, except for reinjection of treated groundwater into the same
formation from which it was withdrawn, as part of a CERCLA cleanup or RCRA corrective
action. Class n and m wells deal with mining and oil and gas production and so are
inapplicable (0 any remedial action at the site. Class V wells constitUte all other injection
wells. There is no regulation of Class V wells.
--
The aquifer underlying the site is considered an underground source of drinking water, so
any well injecting above the aquifer would be a Class IV well. Generally, the consnuction,
operation, and maintenance of a Class IV well is prohibited by 40 CFR 9 144.13. However,
wells used to inject conwninated ground water that has been treated and is being reinjected
into the same formation from which it was drawn are not prohibited if sucb injection is
approved by EP A pursuant to provisions for cleanup of releases under CERCLA, or pursuant
to requirementS and provisions under RCRA. 40 CFR 9 144.23 requires that Class IV wells
be plugged or otherwise closed in a manner accepIable to the EP A Regional Administrator.
2.3.2
Resource Conservation and Recovery Act (Applicable/Relevant and
AppropriaIe)
2.3.2.1
Criteria for Classification of Solid Waste Disposal Facilities Practices
(Apolicable)
The criteria contained in 40 CFR Part 257 set requirements for management of solid waste
disposal. Part 257.3-1(a) states that facilities or p~ctices in the floodplain shall not result in
the washout of solid waste so as to pose a hazard to human life, wildlife, or land or water
resources. Part 257.3-2 provides for the protection of threatened or endangered species.
Part 257.3-3 provides that a facility shall not cause the discharge of pollutants intO waters of
14
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the United States. Part 257.3-.. states that a facility or practice shall not contaminate
underground drinking water.
, ~ ., ..,
.:....J.-.-
Standards A licable to Trans orters of Hazardous Waste A licable)
The regulations at ..0 CFR Part 26332 establiSh standards that apply to persons that transport
hazardous waste within the United States. If hazardous waste is tranSported on a rail-line or
public highway on-site, or if transportation occurs off-site, these regulations will be
applicat e.
2.3.2.3
Standards for Owners and Operators of Hazardous Waste Treatment. Stora.2e,
and Disposal Facilities (Apulicable)
:'J
In considering hazardous waste regulations at the site, the natUre of the hazardous wastes
involved may affect the RCRA regulations that apply to the particular wastes. As discussed
in the contaminant-specific AR.ARs above, the site includes F032 and F034 listed wastes,
other wastes which may be characteristic hazardous waste under RCRA, and certain wastes
which are Bevill-excluded mining wastes for which certain RCRA regulations are prescribed
as 'relevant and appropriate. In addition, tbe site includes wastes which are most
appropriately characterized as KOOl wastes, listed in 40 CFR ~ 261.32 as "bottom sediment
sludge from the treatment of wastewaters from wood preserving processes that use creosote
and/or pentachlorophenol." A water treatment plant is currently operating on site and is
separating the wastes which would fall within the KOOl listing from water before that water
is discharged to Silver Bow Creek. These wastes are collected in carbon f1lters which are
used for the treatment process. Accordingly, the spent carbon containing these wastes should
be classified as KOO 1 listed waste.
Releases from Solid Waste Management Units

The regulations at 40 CPR 264, Subpart F,33 establish requirements for groundwater
protection for RCRA-regulated solid waste management units (i.e., waste piles, surface
impoundments, land treatment units, and landfills). Subpart F provides for three general
types of groundwater monitoring: detection monitoring (40 CFR ~ 264.98); compliance
monitoring (40 CFR ~ 264.99); and corrective action monitoring (40 CFR ~ 264.100).
Monitoring wells must be cased according (0 ~ 264.97(c).
A.
Monitoring is required during the active life of a hazardous waste management unit. At
closure, if all hazardous waste, waste residue, and contaminated subsoil is removed, no
monitoring is required. If hazardous waste remains, the monitoring requirements continue
during the 40 CPR ~ 264.117 closure period.
"
See also !be substantially ~uivalent regulations at ARM 16,4.4.401-'::.5 which are implemented II part ofMontana's luthorized
RCRA propm.
These regulations are inco: ?orated by reference and are implemented by DHES IS part of Montana's authorized RCRA program.
~ ARM 16.44.701.
"
15
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----- -------------------
4 -.
B.
Closure and Post-Closure
~o CFR Pan 264, Subpan G, 34 establishes that haz..1fdous waste management facilities must
be closed in such a manner as to (a) minimize the need for further maintenance and (bj
control, minimize or eliminate, to the extent necessary to protect public health and the
environment, post-closure escape of hazardous wasles, hazardous constiruents, leachate,
contaminated runoff or hazardous waste decomposirion products to the ground or surface
waters or to the atmosphere.
J
Closure includes appropriate caps for the waste management unit. Facilities requiring post-
closure care must undertake appropriate monitoring and maintenance actions, control public
access, and control post-closure use of the property to ensure that the integrity of the fInal
cover, liner, or containment system is not disturbed. 40 CFR 9 264.117. In addition, all
contaminated equipment, structures and soil must be properly disposed of or decontaminated
unless exempt. 40 CFR 9 264.114. A survey plat should be submitted to the local zoning
authority and to the EP A Regional Administrator indicating the location and dimensions of
landfill cells or other hazardous waste disposal uniu with respect to permanently surveyed
benchmarks. 40 CFR 9 264.116. 40 CFR 9 264.228(a) requires that at closure, free liquids
must be removed or solidified, the wastes stabilized, and the waste management unit
covered. If pennanent waste management units arc required because biodegradation
treatment does not achieve risk based cleanup requirements, these requirements will be
applicable to aboveground units containing the waste.
C.
Waste Piles (Applicable)
40 CFR Part 264, Subpart L,3' establishes a framework for the safe operation of a waste
pile until permanent disposal occurs. The framework includes a run-on control system, and a
run-off control system and collection and bolding systems to prevent the funher release of
contaminants from the waste pile. These requireme1lts are applicable to areas where
contaminated soils or materials are temporarily stored or placed prior to treatment or other
disposal.
D.
land Treaanent (Applicable)

The requirements of 40 CFR Part 264, Subpart M," regulate the management of "land
treatment units"37 that treat or dispose of hazardous waste; these requirements are applicable
for any land treattnent unitS eStablished at the site.
..
These regulatioru are incorporated by reference aad are implema8liby DHES.. part of Montana's authorized RCRA program.
2!! ARM 16.44.702.
OJ
These regulatioru are incorporated by reference and are implemesuad by DHES IS part of Montanll's authorized RCRA prognm.
2!! ARM 16.44.702.
..
These regulations are incorporated by reference and are impleme..-t by DHES IS pin oi Montana's authorized RCRA program.
2!! ARM 16.44.702.
n
Land treatment occun when haurdous waste is applied onto or incorporated into tile soil suriace.
16
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The owner or operator of a land treatment unit must design treatment so that hazardous
constiruents placed in the treatment zone are degraded. transformed, or immobilized within
the treatment zone. "Ha;ardous constiruents" are those identified in Appendix vm of .+0
CFR Part 261 that are reasonably expected to be in. or derived from, waste placed in or on
the treatment zone. Design measures and operc.ting pr.lctices must be set up to maximize the
success of degradation, transformation, and immobilization processes. The treatment zone is
the portion of the unsarurated zone below and including the :tU1d surface in which the owner
or operc.tor intends to mcir1tain the conditions necessary for effective degradation,
transfonnation, or immobilization of hazardous constitUents. The maximum depth of the
treatment zone must be 00 more than 1.5 meters (five feet) from the initial soil surface; and
more than one meter (three feet) above the seasonal high water table.
Subpart M also requires the construction and maintenance of control featUres that prevent the
run-off of hazardous constituents and the run-on of water to the treatment unit. The unit
must also be inspected weekly and after storms for deterioration, malfunctions, improper
operation of run-on and run-off control systems, and improper functioning of wind dispersal
control measures.
An unsaturated zone monitoring program m~st t -:- established to monitor soil and soil-pore
liquid to determine whether hazardous constituents migrate out of the treatment zone.
Specifications related to the monitoring program are contained in section 264.278.
::j
E.
Landfills (Applicable)
40 CFR Part 264, Subpart N, 38 applies to entities that dispose of hazardous waste in
landfills.39 The' regulations specify appropriate liner systems and leachate collection
systems for landfills, run-on and run-off management systems, and wind dispersal controlS
for landfills. These regulations set forth specific requirements for landfill monitoring and
inspection, surveying and recordkeeping, and closure and post-closure care. If permanent
waste management units are required because biodegradation treatment does not achieve risk
based cleanup requirements, these requirements will t ~ ~j:plicable to above ground units
containing the waste.
F.
Incinerc.tion (Applicable)
'The regulations at 40 CPR n 264.340 - 351 and 40 CFR Part 265, Subpart 0,40 will be
ARARs for any alternative involving on-site incineration of hazardous waste. Since permits
are not required for on-site incineration, only the substantive standards of the Part 264 permit
requirements would be applicable. Tbe standards require an owner or operator of a hazardous
,.
These regulations are incoJ1lorated by reierence and are implemented by DHES as part oi Montana' s authorized RCRA program.
~ ARM 16.,w.702.
These regulations are incoJ1lorated by reierence and are implemented by DHES IS part oi Montana's authorized RCRA pro~r8m.
~ ARM 16A4.702.
These regulations are incoJ1lorated by reierence Ind are implemented bv DHES IS part oi Montana's authorized RCRA program.
~ ARM 16.,w::'02 Ind 16.~.609I1nterim 5ta01I).
"
17
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--~--- -._----- -_..~-
waste incinerator to conduct a waste analysis in conjunction with obtaining a treatment,
disposal, and storage permit for the incinerator. A permit designates one or more Principal
Organic Hazardous ConstitUents (POHCs) from those constitUents listed in ..0 CFR Part 261.
Appendi.x vID. A POHC designation is based on the degree of difficulty of incineration of
the organic constitUents in the waste feed from trial burns. Organic constitUents that
re~Jresent the greatest degree of difficulty are most likely to be designated a POHC.
Incineration of POHCs designated in the permit must achieve a 99.99 % destruction and
removal efficiency. Incineration of dioxins must achieve a destruction and removal
efficiency of 99.9999%. 40 CFR 9 264. 343(a).
--
An incinerator burning hazardous waste and producing stack emissions of more tban 1.8
kilograms per hour (4 pounds per hour) of hydrogen chloride (HCI) must control HCI
emissions such that the rate of emission is no greater than the larger of either 1.8 kilograms
per hour of 1 % of the Hcl in the stack gas prior to entering any pollution control equipment.
40 CFR 9 264.343(b). A pennitted incinerator must not emit particulate matter in e~cess of
180 milligrams per dry Standard cubic meter (40 CFR 9 264.343(c)). The owner or operator
must monitor combustion temperature, waste feed rate, CO emissions, and combustion gas
velocity. The incinerator must be visually inspected daily, and the emergency waste feed
cutoff system and associated alanns must be tested weekly. At closure, all hazardous waste
residues must be removed from the incinerator site.
2.3.3 Hazardous Materials Transportation Act (Applicable)
The Hazardous Materials Transportation Act (49 USC U 1801-1813), as implemented by the
Hazardous Materials Transportation Regulations (49 CFR Parts 10, 171-177), regulates the
transportation of hazardous materials. The regulations apply to any alternatives involving the
transport of hazardous waste off-site, on public highways on-site, or by rail line.
2.4
FEDERAL STANDARDS TO BE CONSIDERED (TBC's)
2.4.1 Federal Guidance Documents
Many of the procedures and standards to be used in a CERCLA action are set forth in
guidance documents issued by EP A. A list of the types of guidance that are TBC is included
in the preamble to the Final NCP, 55 Fed. Reg. 8765 (March 8, 1990). That guidance,
along with current updates of and additions to that guidance, is to be considered in
conducting the RIfFS and selecting and implementing the remedy at the site.
18
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3.0 STATE OF MONTAl~A A.RARS
3.1
yl0NT~"J"A CO~lAMIN~'IT-SPEClFIC ARARS
3. 1. 1 Water Quality
3.1.1.1
Surface Water Oualitv Standards (Aoolicable)
Under the state Water Quality Act, ~9 75-5-101 et seq., MCA, the state has promulgated
regulations to preserve and protect the quality of surface waters in the state. These
regulations classify state waters according to quality, place restrictions on the discharge of
pollutants to state waters and prohibit the degradation of state waters. The requirements
listed below would be applicable to any discharge' to surface waters in connection with the
remedial action.
ARM 16.20.604(l)(btl (Applicable) provides that Silver Bow Creek (mainstem) from the
confluence of Blacktail Deer Creek to Warm Springs Creek is classified "I" for water use.
...,-:
The "I" classification standards are contained in ARM 16.20.623 (Applicable) of the
Montana water quality regulations. This section states:
..-
[T]he goal of the state of Montana is to have these waters fully support the
following uses: drinking, culinary, and food processing purposes after
conventional treatment; bathing, swimming, and recreation; growth and
propagation of fIshes and associated aquatic life, waterfowl, and furbearers;
and agricultural and industrial water supply.
In order to achieve this goal the 1 classification standards limit discharges of toxic or
deletenous substances from new point sources to the larger of either Gold Book levels~2 or
one-half of the mean instream concentrations immediately upstream of the discharge point. ~3
The effect of this requirement is to require eventual attainment of the Gold Book levels,
while allowing consideration of the site specific stream quality (1/2 the mean instream
concentration). As the quality of the stream improves due to control of other sources,
dischargers will be required to improve the quality of their discharges down to the Gold
Book levels.
Table 26 of the ROD identifies surface water standards which must be met in-stream near the
site for remedial action to be complete. These standards should be met as soon as feasible
and maintained once they are met. Table 27 identifies standards for point source discharges
.,
Unless otherwise specified. .U regulatory cilltions are 10 the AdmiailU'Stive Rules of MontaDa.
"
ARM 16.20.603(10) defines Gold Book levels as .the freshwater cute or chronic levels or the levels for water .nd fish ingestion
that .re listed in Update Number Two (5/1/87) of Qualiry Criteria for Water 1986 
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- --~--._-~--
and run-off water for actions at the site, and these standards must be met for any discharge
prior to discharge.
Short tem exceedances of the standards associated with construction activities and
environmental remediation may be allowed. In-stream standards idemified in Table 26 are to
be met as soon as feasible and maintained thereafter, and consistent compliance with the
standards is a necessary component of remedial acrion completion. However, activities at the
Lower Area One operable unit of the Silver Bow Creek NPL site, including possible
dewatering at lAO, may influence the hydrological balance of the area and cause temporary
increases in organic contamination in Silver Bow Creek above current conditions and the
Table 26 standards. Such exceedances shall not be considered a violation of the Table 26 in-
stream standards, so long as Best Management Practices are implemented to avoid or
minimize such increases at both Lower Area One and the Montana Pole site during
dewatering. TIris determination is consistent with the provisions of Chapter 340, Section 2,
Laws of Montana 1993 and is consistent with a temporary ARAR waiver found in se~tion
121(d)(4)(A) and (C) of CERCLA, 42 U.S.C. g 9621(d)(4)(A) and (C).
I classification standards also include the following criteria:
..,
1.
Dissolved oxygen concentration must not be reduced below 3.0 milligrams per
liter.
2.
Hydrogen ion concentration (Ph) must be maintained within the range of 6.5 to .
9.5.
3.
No increase in naturally occurring turbidity, temperature, concentrations of
sediment and settleable solids, oils, floating solids, or true color is allowed
which will or is likely to create a nuisance or render the waters harmful,
detrimental, or injurious to public health, recreation, safety, welfare, livestock,
wild animals, birds, fish or other wildlife.
4.
No discharges of toxic or deleterious substances may commence or continue
which lower or are likely to lower tile overall water quality of these waters.
Additional standards for any discharge to surface waters are included in:
ARM 16.20.631 (Applicable), which requires that, in designing a disposal system for
industrial waste,44 stteam flow dilution requirements must be based on the minimum
consecutive 7-day average flow which may be expected to occur on the average of
once in 10 years.
ARM 16.20.633 (Applicable), which prohibits discharges containing substances that
will:
Section 75-5-103. MCA. defines 'lndustrial "'late' II ',ny "'Iste ..bSl8DCO from the procesa of busineal or industry or from the
development of Iny D8lUnl resource. togedter ",ith Iny sewage dIM may be present. .
20
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(a) settle to form objectionable sludge deposits or emulsions bene:lth the
surface of the water or upon adjoining shorelines:
(b) create floating debris, scum. a visible oil fUrn (or be present in
concentrations at or in excess of 10 milligrams per liter) or globules or gre:lse
or other floating materials;
(c) produce odors, colors or other conditions which create a nuisance or
render undesirable taStes to fish flesh or make fish inedible;
(d) create concentrations or combinations of materials which are toxic or
hannful to human, animal, plant or aquatic life;
(e) create conditions which produce undesirable aquatic life.
. -4
..,.
ARM 16.20.925 (Applicable), which adopts and incorporates the provisions of 40
C.F.R. Pan 125 for criteria and standards "for the imposition of technology-based
treatment requirements in :MPDES permits. Although the permit requirement would
not apply to on-site discharges, the substantive requirements of pan 125 are .
applicable, i.e., for toxic and nonconventional pollutants treatment must apply the best
available technology economically achievable (BAT); for conventional pollutants,
application of the best conventional pollutant control technology (BeT) is required.
Where effluent limitations are not specified for the particular industry or industrial
category at issue, BCTIBAT technology-based treattnent requirements are determined
on a case by case basis using best professional judgment (BPI). See CERCLA
Compliance with Other Laws Manual, Vol. I, August 1988, p. 3-4 and 3-7.
3.1.1.2
Montana Groundwater Pollution Contro~ System (A~

ARM 16.20.1002 (Applicable) classifies groundwater into Classes I through IV based on the
present and future most beneficial uses of the groundwater, and states that groundwater is to
be classified according to actual quality or actual use, whichever places the groundwater in a
higher class. Class I is the highest quality class; class IV the lowest. . The groundwater at
the Montana Pole site is at least Class n groundwater.
ARM 16.20.1003 (Applicable) establishes the groundwater quality standuds applicable with
respect to each groundwater classification. Concentrations of dissolved substances in Class I
or n groundwater (or Class m groundwater which is used as a drinking water source) may
not exceed Montana MCL values for drinking water. This requirement effectively makes the
current MCL values applicable and not just relevant and appropriate requirements.
Concentrations of other dissolved or suspended substances must not exceed levels that render
the waters harmful, detrimental or injurious to public health. Maximum allowable
concentration of these substances also must not exceed acute or chronic problem levels that
would adversely affect existing or designated beneficial uses of groundwater of that
classification.
The range of MC~ specified by Montana law is much more limited than the federal MCLs
and does not include many of the primary contaminants of concern at the Montana Pole site.
The groundwater standards that are specified, including the Montana MCLs for arsenic,
cadmium, chromium, lead, benzene and para-dichlorobenzene, are to be attained throughout
21
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the contaminated plume. If such standards are not attainable. an .~ waiver may be
appropriate.
A~\I 16.20.1011 (Applicable) provides that any groundwater whose existing quality :s
higher than the standard for its classification must be maintained at that high quality unl~ss
~he board is satisfied that a change is justifiable for economic or social development and will
not preclude present or an.jcipated use of such waters.
3.2
MONTANA LOCATION-SPECIFIC ARARS
3.2.1 Floodplain and Floodway Management
3.2.1.1
Floodplain and Floodway Management Act (Ap,plicable or Relevant and
Appropriate)
Section 76-5-401, MCA, (Applicable) specifies the uses permissible in a floodway and
generally prohibits permanent structures, fill, or permanent storage of materials or
equipment.
.,
Section 76-5-402, MCA, (Applicable) specifies uses allowed in the floodplain, excluding the
floodway, and allows Structures meeting certain minimum standards.
Section 76-5-403, MCA, (Applicable) lists certain uses which are prohibited in a designated
floodway, including:
1.
any building for living purposes or place of assembly or permanent use by
human beings,
2.
any structure or excavation that will cause water to be diverted from the
established floodway, cause erosion, obst'11~t the natural flow of water, or
reduce the carrying capacity of the floodway, or
3.
the construction or permanent storage of an object subject to flotation or
movement during flood level peric1s.
3.2.1.2
Floodplain Management ~ations (AW~evant anq Awropriate)
ARM 36.15.216 (Relevant and Appropriate) specifies factors to consider in determining
whether a pennit should be issued to establish or alter an artificial obstruction or
nonconforming use in the floodplain or floodway. While permit requirements are not
directly applicable to activities conducted entirely on site, the criteria used to detennine
whether to approve establishment or alteration of an artificial obstruction or nor.conforming
use should be applied by the decision-makers in evaluating proposed remedial alternatives
which involve artificial obstructions or nonconfonning uses in the floodway or floodplain.
Thus the following criteria are relevant and appropriate considerations in evaluating any such
obstructions or uses:
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1.
')
3.
4.
- ~---~--
------ -
the danger to life and property from backwater or diverted flow caused by the
obstruction;
the danger that the obstruction will be s\I'ept downstream to the injury of
others:
the availability of alternative locations:
the construction or alterntion of the obstruction in such a manner as to lessen
the danger;
5.
tbe permanence of the obstruction; and
6.
the anticipated development in the foreseeable future of tbe area which may be
affected by the obstruction.
ARM 36.15.603 (Relevant and Appropriate) provides tbat proposed diversions or changes in
place of diversion must be evaluated by the DNRC to determine whether they may
significantly affect flood flows and, therefore, require a permit. While permit requirements
are not applicable for remedial actions conducted entirely on site, the following criteria used
to determine when a permit shall nQ! be granted are relevant and appropriate:
-
-
1.
the proposed diversion will increase the upstream elevation of the 100-year
flood a significant amount (1/% foot or as otherwise determined by the permit
issuing authority);
2.
the proposed diversion is not designed and constructed to minimize potential
erosion from a flood of loo-year frequency; and
3.
any permanent diversion sttUcture crossing the full width of the stream channel
is not designed and constrUcted to safely withstand up to a flood of lOO-year
frequency.
ARM 36. 15 .604 (Relevant and Appropriate) precludes new consttUction or alteration of an
artificial obstruction that will significantly increas~ the upstream elevation of the flood of
lOO-year frequency (1/1 foot or as otherwise determined by the pennit issuing authority) or
significantly increase flood velocities.
ARM 36.15.605(1) (Relevant and Appropriate) and ARM 36.15.605(2) (Applicable)
enumerate artificial obsnuctions and nonconforming uses that are prohibited within the
designated floodway except as allowed by permit and includes "a strUcture or excavation tbat
will cause water to be diverted from the established floodway, cause erosion, obstruct the
natural flow of water, or reduce the carrying capacity of the floodway .,. ." Solid and
hazardous waste disposal and stornge of toxic, flammable, hazardous, or explosive materials
are also prohibited.
"')'"
_.J
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AR..'v! 36.15.606 (Relevant and Appropriate) enumerates flood control works that are allowed
within designated floodways pursuant to pennit. Although the pennit requirements are not
applicable for activities conducted entirely on site, the following conditions are relevant md
appropriate:
1. flood control levies and flood walls are allowed if they are designed and
constructed to safely convey a flood of lOO-year frequency and their cumulative effect
COI abined with allowable flood fringe ~ncroachments does not increase the
unobstructed elevation of a flood of 1000year frequency more than 1/2 foot at any
point;
2. riprap, if not hand placed, is allowed if it is designed to withstand a flood of 100-
year frequency, does not increase the elevation of the l00-year frequency flood, and
will not increase erosion upstream, downstream, or across stream from the riprap site;
...,.
3. channelization projects are allowed if they do not significantly increase the
magnirude, velocity, or elevation of the flood of 100-year frequency downstream from
such projects;
4. darns are allowed if they are designed and constructed in accordance with
approved safety standards and they will Dot increase flood hazards downstream either
through operational procedures or improper hydrologic design. .
ARM 36.15.703 (Applicable) is applicable in flood fringe areas (Le., areas in the floodplain
but outside of the designated floodway) of the site and prohibits, with limited exceptions,
solid and hazardous waste disposal and storage of toxic, flammable, hazardous, or explosive
materials.
3.2.1.3
Solid Waste Mana2ement Re2Ulations (Applicable)
A.Rlv( 16.14.505 (Applicable), in establishing standards for solid waste disposal sites,
provides that such sites may not be located in a 100 year floodplain.
3.2.2
Natural Streambed and Land Preservation Standards (Applicable)
ARM 36.2.404 (Applicable) establishes minimum standards which would be applicable if a
remedial action alters or affects a streambed, including any channel change, new diversion,
riprap or other streambank protection project, jetty. new dam or reservoir or other
commercial, industrial or residential development. No such project may be approved unless
reasonable efforts will be made consistent with the purpose of tbe project to minimize the
amount of stream channel alteration, insure that the project will be as pennanent a solution as
possible and will create a reasonably pennanent and stable situation, insure that the project
will pass anticipated water flows without creating LMmfuI erosion upstream or downstream,
minimi7e turbidity, effects on fish and aquatic habitat, and adverse effects on the natural
beauty of the area and insu~e that streambed gravels will not be used in the project unless
24
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there is 00 reasonable alternative. Soils erosion and sedimentation must be kept to a
minimum. See also ~ 75-7-102, MCA.
3.3
In the foUowing action-specific AR,A.Rs, the natUre of the action triggering applicability of
the requirement is stated in parentbesis as part of tbe heading for each requirement.
MONTANA ACTION-SPECIFIC ARARS
3.3.1.
Water Quality
3..).1.1
Groundwater Act (Aoplicable) (Construction and maintenance of groundwater
weUs)
Section 85-2-505, MCA, (Applicable) precludes the wasting of groundwater. Any weU
producing waters that contaminate other waters must be plugged or capped, and wells must
be constructed and maintained so as to prevent waste, contamination, or pollution of
groundwater.
If remo=dia1 action at the site requires any reconsuuction or modification of any public water
supply line or sewer line, the consnuction SUQdards specified in ARM 16.20.401(3)
(Applicable) must be obserled. A public _er line crosses the Montana Pole site, and the
sewer line bedding is considered a potential pathway of contamination.
Public Water Suuolv Re!!Ulations (Auolicable) (Reconstruction or modification
of public water or sewer lines on the site)
3.3.1.2
-I\-
3.3.2
Air Quality'"
bll Oualitv Re~lations (Auolicable) (Excavation/earth-moving; transportation;
incineration; storage of petroleum distillates)
3.3.2.1
Dust suppression and control of certain subSlallCes likely to be released into the air as a result
of earth moving, transportation and similar actions may be necessary to meet air quality
requirements. The ambient air standards for specific contam;nants and for particulates are
set fonh in the federal conwninant-specific section above. Additional air quality regulations
under the state Clean Air Act, ~~ 75-2-101 ~ mo.. MCA, are discussed below.
0'
Tho air quality ARAIU inc:luded in this analysil Ire idelUified on dI. luumption that no remedial Iction It the site wiu coastitUte
I 'lI18jor stlUoDar y sourc.: or 'major modification: IS defined in ARM 16.8.921. Sbould any part of I remedy con.sUnlle such
a lOurce, IOme additional RlquiremtllllS would be applicable, iadudml the Imbient ait incrementS of ARM 16.8.92.5!U!9'
Simil.rly. if Iny part of I remedy should constiwle a new or allefOlli lOurce of lir pollution wbichhlS the pOlenlial to emil more
than 2S IOns per year of Iny pollutant addreaaed by the Clean Air Act regulalions. tile owner or operatOr must install the
maximum air pollution c:onaol clplbility which is technically practicable and ec:OoomicIUy feasible. as provided by ARM
16.8.1103 (belt Ivail.ble conuol tec:hnology shall be uli~ed).
25
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--_..~--_._~~~---
c -.
AIUvI16.8.1302 (Applicable) lists certain wastes that may not be disposed of by open
buming~6, including oil or petroleum products, RCRA.. hazardous wastes. chemicals. and
treated lumber and timbers. Any waste which is moved from tbe premises where it was
generated and any trade waste (material resulting from .:onstruction or operation of any
business, trade, industry or demolition project) may be open burned only in accordan(e ':\:~h
the substantive requirements of 16.8.1307 or 1308.
ARM 16.8.1401(3) and (4) (Applicable) states that no person shall caus~ or authorize the
production, handling, transportation or storage of any material unless reasonable precautions
to control emissions of airborne particulate matter are taken.
ARM 16.8.1404 (Applicable) states that "no person may cause or authorize emissions to be
discharged in the outdoor atmosphere... that exhibit an opacity of tWenty percent (20 %) or
greater averaged over six consecutive minutes."
:2.
ARM 16.8.1406 (Applicable) prohibits certain emissions from incinerators, including
emissions of particulate matter in excess of 0.10 grains per standard cubic foot of dry flue
gas, adjusted to twelve percent carbon dioxide and calculated as if no auxiliary fuel had been
used, emissions which exhibit an opacity of ten percent (10%) or greater averaged over six
consecutive minutes.
Two bills were passed by the 53rd Montana LegisJature directly addressing the issue of
incineration of wastes. Section 75-2-215, MCA, as amended by 1993 Laws of Montana.
Chapter 129, provides that S
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.~"1 26A.i61 (Relevant and Appropriate) specifies measures that must be implemented to
control fugitive dust emissions during certain mining and reclamation activities. Such
measures are relevant and appropriate requirements to control fugitive dust ~missions during
excavation, earth moving and transportation activities ,:onducted as part of the remedy at the
SIte.
ARM 26.4.501 and SOlA (Relevant and Appropriate) give general backfilling and fInal
grading requirements.
~eclamation and Reveoetation R
(Excavation)
3.3.2.2
AIUv1 26.4.514 (Relevant and Appropriate) sets out contOuring requirements.
ARM 26.4.519 (Relevant and Appropriate) provides that an operator may be required to
monitor settling of regraded areas.
ARM 26.4.638 (Relevant and Appropriate) specifies sOOiment control measures to be
implemented during operations.
ARM 26.4.702 (Relevant and Appropriate) requires that during the redistributing and
stockpiling of soil (for reclamation):
-
. 1. . regraded areas must be deep-tilled, subsoiled, or otherwise treated to
eliminate any possible slippage potential, to relieve compaction, and to promote root
penetration and penneabiJity of the underlying layer; this prepaIation must be done on the
contour whenever possible and to a minimum depth of 12 inches;
2. redistribution must be done in a manner that achieves approximate
uniform thicknesses consistent with soil resource availability and appropriate for the
postmining vegetation, land uses, contours, and surface water drainage systems; and
3. redistributed soil must be reconditioned by subsoiling or other
appropriate methods.
AlUv1 26.4.703 (Relevant and Appropriate) Wht.i1 using materials other than, or along with,
soil for fInal surfacing in reclamation, the operator must demonstrate that the material (1) lS
at least as capable as the soil of supporting the approved vegetation and subsequent land use,
and (2) the medium must be the best available in the area to support vegetation. Such
substitUtes must be used in a manner consistent with the requirements for rCdistribution of
soil in AlUv1 26.4.701 and 702.
ARM 26.4.714 (Relevant and Appropriate) requires use of a mulch or cover crop or both
until an adequate permanent cover can be established. Use of mulching and temporary cover
may be suspended under certain conditions.
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ARM 26.4.716 (Relevant and Appropriate) establishes the required method of revegetation.
and provides that introduced species may be substituted for native species as pan of an
approved plan.
AR!v! 26.4.718 (Relevant and Appropriate) requires the use of soil amendments and other
means such as irrigation, management, fencing, or ather measures, if necessary to establish a
diverse and pennanent vegetative cover.
3.4
OTIlER LAWS
The following "other laws" are included here to provide a reminder of other legally
applicable requirements for actions being conducted at the site. They do not purpon to be an
exhaustive list of such legal requirements, but are included because they set out related
concerns that must be addressed and, in some cases, may require some advance planning.
They are not included as ARARs because they are not" environmental or facility siting
laws." As applicable laws other than ARARs, they are not subject to ARAR waiver
provisions.
Section 121(e) of CERCLA exempts removal or remedial actions conducted entirely on an
NFL site from federal, state or local pennit requirements, and this exemption appears broad
enough to cover even permits required under "other laws." However, the
administrativel substantive distinction used in identifying ARARs applies only to ARARs and
not to other applicable laws. Thus even the administrative requirements, e.g., notice
requirements, of these other laws must be complied with in this action. Similarly, fees that
are based on something other than issuance of a pennit are applicable.
3.4.1
Groundwater Act
Section 85-2-516, MCA, states that within 60 days after any well is completed a well log
repon must be flied by the driller with the DNRC and the appropriate county clerk and
recorder.
3.4.2
Water Rights
Section 85-2-101, MCA, declares that all waters within the State are the State's property,
and may be appropriated for beneficial uses. The wise use of water resources is encouraged
for the maximum benefit to the people and with minimum degradation of natuml aquatic
ecosystems.
Parts 3 and 4 of Title 85, MCA, set out requirements for obtaining water rights and
appropriating and utilizing water. All requirements of these parts are laws which must be
complied with in any action using or affecting waters of the state. Some of the specific
requirements are set fonh below.
Section 85-2-301, MCA, of N{omana law provides that a person may only appropriate water
for a beneficial use.
23
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Section 85-2-302, ~1CA. specifies that a person may not appropriate water or commence
construction of diversion, impoundment, withdrawal or distribution works therefor except by
applying for and receiving a pennit from the Monrana Department of ).iarural Resources and
Conservation. While the' pennit itself may not be required under federal law. appropriate
notification and submission of an application should be performed and a pennit should be
app lied for in order to establiSh a priority date in the prior appropriation sy Stem. .'\ 190 I
a.mendment imposes a fee of S 1. 00 per acre foot for appropriations of ground water. effective
until July 1, 1993.
Section 85-2-306, MCA, specifies the conditions on which groundwater may be appropriated,
and, at a minimum, requires notice of completion and appropriation within 60 days of well
completion.
Section 85-2-311, MCA, specifies the criteria which must be met in order to appropriate
water and includes requirements that:
there are unappropriated waters in the source of supply;
 1.
 2.
~ 3.
the proposed use of water is a beneficial use; and
the proposed use will not interfere unreasonably with other planned
uses or developments.
Section 85-2-402, MCA, specifies that an appropriatOr may not change an appropriated right
except as provided in this section with the approval of the DNRC.
Section 85-2-412, MCA, provides that, where a person has diverted all of the water of a
stream by virtue of prior appropriation and there is a surplus of water, over and abOve wbat
is actUally and necessarily used, such surplus must be retUrned to the stream.
3.4.3
ARM 9 16.42.101 addresses occ\!pational noise. In accordance with this
section, no worker shall be exposed to noise levels in excess of the levels specified in this
regulation. This regulation is applicable only to limited categories of workers and for moSt
workers the similar federal standard in 29 CFR 9 1910.95 applies.

ARM 9 16.42.102 addresses occupational air contaminants. The purpose of
this rule is to establish maximum threshold limit values for air contaminants under which it is
believed that nearly all workers may be repeatedly exposed day after day without adverse
health effects. In accordance with this rule, no worker shall be exposed to air contaminant
levels in excess of the threshold limit values listed in the regulation. This regulation is
applicable only to limited categories of workers and for most workers the similar federal
standard in 29 CFR 9 1910.1000 applies.
Occupational Health Act; 99 50-70-101 et ~., MCA
29
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--~.~-_._---~-
~ -.
3.4.4
Federal Occupational Health and Safety Act
On-site work must comply with the provisions of 29 CFR g 1910.95.
3A.5
:Vlontana Safety Act
Sections 50-71-201, 202 and 203, MCA, state that every employer must provide and
maintain a safe place of employment, provide and require use of safety devices and
safeguards, and ensure that operntions and processes are reasonably adequate to render the
place of employment safe. The employer muSt also do every other thing reasonably
necessary to protect the life and safety of its employees. Employees are prohibited from
refusing to use or interfering with the use of safety devices.
3.4.6
Employee and Community Hazardous Chemical Information Act
Sections 50-78-201, 202, and 204, MCA, state that each employer must post notice of
employee rights, maintain at the work place a list of chemical names of each chemical in the
work place, and indicate the work area where the chemical is stored or used. Employees
must be informed of the chemicals at the work place and trnined in the proper handling of
the chemicals.
...:...
30
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:\il0L'T.-\.."A POLE ROD - DECISION Sr~[\
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Locations of tbe Administr".ltive Record:
Notes:
1.0
:\tlontana Department of Health and Environmental Sciences
Soud and Hazardous Waste Bureau
Superfund Program
616 Helena Avenue, Room 302
Helena. :\-lontana 59601
Montana Tecb Library
West Park Street
Butte, Montana 59701
Updated: September 21, 1993
Administrative Record Site File Index
Montana Pole Superfund Site
Administrative Record For
Selection of Remedial Action
1.
Only sections appearing below in Bold type are presently contained in
the administrative record. Those listings appearing in ordinary type are
anticipated for a later stage in the proceedings.
2.
The Removal Response section consists primarilY of documents
appearing in the EPA Administrative Record for the Removal Actions.
This EP A record was compiled during the removal action conducted at
the Montana Pole site in 1985-1987 and during the removal action
conducted at the site in 1992-1993. For consistency, these rues are
arranged in this record essentially tbe same as they appear in the EP A
record.
SITE IDENTIFICATION
1.01 Background Information including RCRA
1.02 Site Inspection/Site Investigation Reports
1.03 Preliminary Assessment (PA) Report
1.04 Sampling and Analytical Data
1.05 Site Photographs/Slides
2.0
REMOV AL RESPONSE
2.01 Site Investigation
2.02 pollution Reports (POLREPS)
2.03 Action Memorandum
2.04 Work Plans
2.05 Site Safety
2.06 Appllcations/Permits
2.07 Meetings/Schedules
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2.0
'"
3.0
4.0
(Removal Response)
2.08
2.09
2.10
2.11
2.12
2.13
2.14
2.15
2.16
2.17
2.18
2.19
2.20
2.21
Sampling Plans
Sampling and Analysis Data/Chain of Custody Forms
Technical Assistance Team (TAT) Report
Engineering Evaluation/Cost Analysis (EE/CA)
EmulsionJRecovery System
Status Reports/l\-lonthly Reports
Logbooks/Notes
Community Relations
Requests under the Freedom of Information Act (FOIA)
General Correspondences
Liquid Dioxin Disposal Proposals
Technical Information
Post Removal Issues
1992 Tme Critical Removal Action (TCRA)
2.21.1 General Correspondence
2.21.2 Pollution Reports (POLREPS)
2.21.3 Action Memorandum
2.21.4 ARCO Submittal for Administrative Record
2.21.5 Community Relations
2.21.6 Status ReportslMonthly Reports
2.21.7 Engineering Evaluation/Cost Analysis (EElCA)
RIfFS PLANNING
3.01 RIIFS Scoping
3.02 Workplans
3.02.1 Volume I
3.02.2 Volume IT (Includes Sampling and Analysis Plan and
Schedule)
3.02.3 Standard Operating Procedures (SOPs)
3.02.4 Supplemental or Additional Work Plans
3.02.5 Dismantled Equipment Work Plans
Quality Assurance Project Plan (QAPP)
Data Management Plan
Site Management Plan
Health and Safety Plan
Review Comments
Respoase to Comments
3.03
3.04
3.05
3.06
3.07
3.08
REMEDIAL INVESTIGATION
4.01 Historic:al and Archaeological Resources Reports
4.02 Endangered Species Report
4.03 Floodplain Report
4.04 Wetland Report
4.05 MonthJy Reports
4.06 Sampling and Analysis Data/Chain of Custody Forms
4.06.1 Round 1 Raw Data
4.06.2 Round 1 and 2 Data Validation Report
2
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9.0
10.0
11.0
...
....
..-
12.0
.
PUBUC HEALTH AND E.J.WIROmIENT AI. ASSESSMENTS (PRE-\.)
9.01 Agency for Toxic Substances and Disease Registry (ATSDR) Healtb
Assessments
Preliminary Endangerment Assessment (PEA)
ARCO Risk Assessment Scoping Documents
Baseline Risk Assessment
9.04.1 Baseline Risk Assessment Report (CDM, August 1991)
9.04.2 Revised Final Baseline Risk \ssessment
9.02
9.03
9.04
NATURAL RESOURCE TRUSTEES
10.01 Notices Issued
10.02 Correspondence
PUBUC PARTICIPATION
11.01 Community Relations Plan
11.02 Press Releases
11.03 Press Clipping
11.04 Fact Sheets
11.05 Public Notice(s) (Availability of the Al'hninim:rative Record File and
Proposed Plan, Public Hearin:s)
Public Hearings/Transcripts
Documentation of Other Public Meetings
Comments on Adminiqrative Record
Response to Comments on AJiminiqrative Record
11.06
11.07
11.08
11.09
TEqINICA:. SOURCES AND GUIDANCE DOcUMENTS
12.01 State Guidance/Bibliography of Guidance Documents .
12.02 EPA Removal Action Administrative Record Index
12.03 Soil Washing Studies
12.04 Other Technical Information
A summary or
Additional information is located in a confidential me.
explanation of this material is included in this record.
4
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4.0
5.0
..,
'"
6.0
..
7.0
8.0
'"
--~- ---,._~--_._----_.._--...._---_...._- ---
(Remdedial Invest:.gation)
~.07
4.08
4.09
... --
4.06.3 Round 2 Raw Dcita
4.06.4 Supplemental Raw Data
4.06.5 Supplemental Data Validation Reports
4.06.6 Split Sample Data
Remedial Investigation Reports
4.07.1 Preliminary Draft Rl Report
4.07.2 Draft RI Reports
4.07.3 Final RI Report
Review Comments
Response to Comments
FEASIBILITY STUDY .
5.01 Technologies Screening Document
5.02 Alternatives Screening Document
5.03 Treatability Work Plan
5.04 Treatability Reports
5.05 ARAR Determinations
5.05.1 Preliminary Identification of Contaminant-specific ARARs
5.05.2 ARCO ARARs Scoping Documents
5.05.3 Screening and Description of Potential ARARs
Institutional Controls Reports
Prelimin~ry Remediation Goals
Draft FS Reports
Final FS Report
ARCO'RIJFS Position Paper
Proposed Plan
Public Comments
5.06
5.07
5.08
5.09
5.10
5.11
5.U
RECORD OF DEOSION (ROD)
6.01 ROD (Declaration and Decision Summary)
6.02 Responsiveness Summary
STATE COORDINATION
7.01 EPA/State Cooperative Agreement
ENFORCEMENT
8.01 ARCO/State Adminiq;rative Order on Consent
8.02 PRP Responses
8.03 Notice Letters
8.04 Enforcement History-Correspondence [Miner's Bank prior to 1992]
(may contain non-~1iner's Bank correspondence in 1992 and later)
Pleadings in Injunction Action (State v. ~finers Bank and :\-Iontana
Pole)
Miner's Bank Liability/Settlement (1992 & forward)
Complaint and Depositions 0...1ontana Pole v. Laucks)
8.05
8.06
8.07
3
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