United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R09-90/053
September 1990
&EPA Superfund
Record of Decision:
Louisiana-Pacific, CA
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I REPORT DOCUMENTATION 11. REPORT NO. I ~ 3. Recipients Acce..ion No.
PAGE. EPA/ROD/R09-90/053
Tille and Subtitle 5. Report Date
SUPERFUND RECORD OF DECISION
Louisiana-Pacific, CA 09/28/90
First Remedial Action 6.
7. Author(s) 8. Performing Organization Repl No.
8. Performing Orgalnlzatlon Name and Address 10. ProjecllTsaklWork Unit No.
11. Contract(C) or Grant(G) No.
(C)
(G)
12. Sponsoring Organization Name and Address 13. Type 01 Report & Period Covered
U.S. Environmental Protection Agency 800/000
401 M St reet, S.W.
Washington, D.C. 20460 14.
15. Supplementary Notes
18. Abetrsc1 (Limit: 200 words)
The Louisiana-Pacific (L-P) site is comprised of an active wood processing plant and
a landfill in Butte County, Oroville, California. The plant and landfill are 1/2 mile
apart, separated by another Superfund site, the Koppers Company site. The plant lies
within the Feather River floodplain with the river located 1/2 mile west of the site.
;Area land use is agricultural, residential, commercial, and industrial. The plant
rests on mine tailings created by dredge mining activities conducted from 1900 until
1969. Since 1970, plant activities have included log storage, lumber production, and
hardboard manufacturing. Wood wastes have been disposed of onsite at the landfill.
Possible sources of contamination at the s.ite include discharge of wastewater and
plant process wastes from the site, and contaminants migrating from ~he adjacent
Koppers site. Between 1970 and 1984, a fungicide spray containing pentachlorophenol
(PCP) was used onsite to prevent fungal discoloration of cut lumber. In 1973, State
investigations discovered PCP and various other contaminants in downgradient ground
water and surface water, as well as, sawdust and wood waste at the plant and landfill.
In addition, contamination has been detected at the adjacent Koppers Company site
(See Attached Page)
17. Document Analyais L Deacrlptors
Record of Decision - Louisiana-Pacific, CA
First Remedial Action
Contaminated Media: soil, gw -
Key Contaminants: VOCs (toluene), other organics (formaldehyde), metals (arsenic,
lead, zinc)
b. identifiers/Open-ended T erme
c. COSA TI F1eIcllGroup
18. Avallabinty Slatemenl 18. Security Cia.. (This Report) 21. No. 01 Pages
None 76
I 20. Security Cia.. (Thla Page) n Price
Non""
2n (4.77)
50272-101
(See ANSI-Z38.18)
See In.trucfioM on RtI".I'tIII
(Formerty NTIS-35)
Department 01 Commerce
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EPA/ROD/R09-901053
Louisiana-Pacific, CA
?irst Remedial Action
Abstract (Continued)
This Record of Decision (ROD) documents an interim remedy and the need to collect
additional data on arsenic and formaldehyde levels on and near the site. The primary
contaminants of concern affecting the soil and ground water are VOCs including toluene;
organics including formaldehyde; and metals including arsenic, lead, and zinc.
The selected interim remedial action for this site includes onsite ground water
monitoring; and implementing institutional controls including deed and well permit
restrictions, and site access restrictions, such as fencing. The estimated present
worth cost for this remedial action is $193,000. There are no significant O&M costs
associated with this remedial action.
PERFORMANCE STANDARDS OR GOALS: EPA has determined that before final remedial action
goals for the site can be set, additional information is necessary to determine
background arsenic levels in soil, and formaldehyde and arsenic levels in ground water.
Therefore, no chemical-specific goals are provided for this remedial action.
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INTERIM RECORD OF DECISION
LOUISIANA-PACIFIC SUPERFUND SITE
OROVILLE, CALIFORNIA
U.S. Environmental Protection Agency
Region 9
San Francisco, California
September 1990
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Section
LOUISIANA-PACIFIC SUPERFUND SITE
INTERIM RECORD OF DECISION
Table of content.
DECLARATION
DECISION SUMMARY
1.0
2.0
3.0
4.0
5.0
6.0
7.0
SITE NAME, LOCATION, DESCRIPTION
SITE HISTORY AND ENFORCEMENT
COMMUNITY PARTICIPATION
SCOPE AND ROLE OF DECISION
SUMMARY OF SITE CHARACTERISTICS
5.1
5.2
Potential Sources of contamination
5.1.1 Wastewater
5.1.2 Process Wastes
5.1.3 Miqration 9f Contaminants from the
Koppers Site
Nature and Extent of contamination
SUMMARY OF SITE RISKS
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
Risk Levels of Concern
Chemical Levels of Concern
Exposure to Hardboard Plant Emissions
Exposure to Surface Soil at the Plant
Inqestion of Groundwater at the Plant
Inhalation of Volatile Orqanics in
Groundwater at the.Plant (FU5)
Inhalation of Volatile orqanics in
Groundwater at the Landfill (FU7)
Environmental Risks
Risks to be Addressed
by Interim Remedial Action
(CU5)
(FU1)
(FU4)
DESCRIPTION OF ALTERNATIVES
Paqe
1
5
7
8
9
9
9
9
10
11
12
26
26
28
34
34
35
36
36
40
40
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Section
10.0
11.0
12.0
8.0
APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS
(ARARs) AND TO-BE-CONSIDERED CRITERIA
8.1 contaminant-Specific ARARs
8.1.1 Federal Drinking Water Standards
8.1.2 State Drinking Water Standards
8.1.3 Ambient Water Quality Criteria
8.2 Action-Specific ARARs
8.3 Location-Specific ARARs
8.3.1 Fault Zone
8.3.2 Floodplain
8.4 To-Be-Considered Crit~ria
9.0
SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
SELECTED REMEDY
10.1 Selected Soil Remedy
10.2 Selected Groundwater Remedy
DOCUMENTATION OF SIGNIFICANT CHANGES
STATUTORY DETERMINATION
Page
42
42
44
44
44
44
44
44
45
45
45
47
47
48
49
50
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Table
5-1
5-2
6-1
6-2
6-3
6-4
6-5
8-1
LIST OF TABLES
- -
Chemicals of Potential Concern at the
Louisiana-Pacific Site-
Concentration of Chemicals of Potential Concern
Summary of Potential Health Risks Identified by
the Endangerment Assessment: Louisiana-Pacific site
Risk-Based Residual Concentrations and
corresponding Sample Locations and Concentrations
Arsenic Concentrations in Soil and Shallow
Groundwater L-P Plant
Certain Physical Characteristics of Groundwater
from Plant Monitoring Wells
Summary of Potential Environmental Effects
Potential Contaminant-Specific Applicable or
Relevant and Appropriate Requirements (ARARs) ,
Louisiana-Pacific Site
Paqe
13
15
22
27
29
30
38
43
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Fiaure
1-1
1-2
1-3
6-1
6-2
6-3
LIST OF FIGURES
Paqe
site Location Map
2
L-P Plant Features
3
L-P Landfill Features
4
Arsenic Distribution in Surface Soil - L-P Plant
31
Arsenic Distribution in Shallow Groundwater -
L-P Plant
32
Formaldehyde Distribution in Shallow Groundwater -
L-P Plant
33
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INTERIM RECORD OP DECISION
DECLARATION
SITE NAME AND LOCATION
Louisiana-Pacific Corporation
Oroville, California
STATEMENT OF BASIS AND PURPOSE
This decision document presents the interim soil and ground
water remedial actions. selected for the Louisiana-Pacific (L-P)
site in Oroville, California, developed in accordance with the
Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA), as amended by the Superfund Amendments and
Reauthorization Act (SARA), and to the extent practicable, the
National Contingency Plan (NCP). This decision is based on the
administrative record for this site.
The State of California concurs with the selected remedy.
ASSESSMENT OF THE SITE
The actual or potential release of hazardous substances from
this site, if not addressed by implementing the interim response
actions selected in this Record of Decision (ROD), may present an
imminent and substantial endangerment to public health, welfare,
or the environment.
DESCRIPTION OF THE REMEDY
. This interim remedy addresses the principal documented
public health threats from the site contamination. Actions have
been selected to address risks posed by contaminated surface soil
and shallow groundwater at the plant and groundwater beneath the
landfill.
The selected soil remedy consists of:
o
Deed restrictions on residential use of the L-P plant
site, and
Site access restrictions, e.g., fencing the perimeter
of the L-P plant.
o
The deed restriction is based on existing knowledge of arsenic
contamination at the plant. Additional data on levels of arsenic
-------
in soils at or near the site is necessary to determine background
and to set appropriate remedial action goals for the site.
The selected groundwater remedy consists of:
o
Well permit restrictions to (1) prohibit the drilling
of shallow aquifer wells on or near the L-P plant, (2)
provide proper seals on deep wells drilled through the
shallow aquifer on or near the L-P plant, and (3)
prohibit drilling of deep wells at the L-P landfill;
Monitoring of onsite wells to obtain additional infor-
mation about the presence of formaldehyde in
groundwater at the site, and to obtain additional in-
formation about background levels of arsenic; and
Const~uction and monitoring of additional offsite wells
if formaldehyde is detected above the detection limit
during monitoring of onsite wells.
o
o
DECLARATION
This interim action is protective of human health and the
environment, complies with Federal and state applicable or
relevant and appropriate requirements directly associated with
this action, and is cost effective. Because this action does not
constitute the final remedy for the site, the statutory
preference for remedies that employ treatment that reduces
toxicity, mobility, or volume a~ a principal element will not be
satisfied by this interim action. The final remedial action will
address fully the principal threats posed by this site.
q .~~ .~'O
~w~
Dan1el W. McGovern.
~Regional Administrator
Date
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INTERIM RECORD OF DECISION
DECISION SUMMARY
1.0
SITE NAME, LOCATION, DESCRIPTION
The Louisiana-Pacific (L-P) site consists of a wood process-
ing plant and landfill located in Butte County just south of the
city limits of Oroville, California (population 10,560) (see
Figure 1-1, Site Location Map). Log storage, lumber production,
and hardboard manufacturing take place at the plant, and disposal
of wood wastes takes place at the landfill. The plant and
landfill are located about 1/2 mile apart and are separated by
the Koppers Company Superfund site, which is also on the EPA's
National Priorities List. Features of the L-P plant and landfill
are shown in Figures 1-2 and 1-3, respectively.
The L-P plant lies in the Feather River floodplain at an
elevation of about 145 feet. The northern part of the plant is
occupied by buildings and paved with asphalt. The central part
of the plant has been graded relatively level for log storage.
The western margin and southwest corner of the plant retain much
of the historic, irregular dredge-tailing topography since
modified by quarrying for log-deck base material.
The Feather River is located about 1/2 mile west of the
plant at an elevation of 120- feet above sea level. The Feather
River floodplain extends from the river to the Baggett-Marysville
Road (south and east of the L-P plant - see Figure 1-1) where it
ends at a prominent bluff eroded into hills and ravines. The
bluff rises 100 to 170 feet above the floodplain to meet the
. gently rolling upland extending to the south and east.
The landfill operation has filled one of
eroded bluff. The effect of the landfill has
of a nearly flat ridge at an elevation of 270
ravine once was located.
the ravines in the
been the formation
feet where the
Surface water run-off flows westward from the L-P landfill
onto the Koppers site and then into the log deck pond at the
southeast corner of the L-P plant. Plant drainage flows
generally south into the log deck pond but is complicated by
closed drainages where run-off infiltrates to groundwater.
Drainage from the log deck pond flows through a chain of three
ponds immediately south of the L-P plant boundary, and then west
to gravel pit ponds nearer the Feather River.
- 1 -
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OROVILLE DAM BLVD
OROVILLE STATE
WILDLIFE AREA
LOUISIANA-PACIFIC
LANDFILL
LOUISIANA
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LANDFILL
AREA
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Figure 1-1. S ITE LOCATION MAP
- 2 -
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EXPLANA TION
. L.P Industrial Well
BlR . Boiler Well
DFW - Diesel Fire Well
EFW - Electric Fire Well
MUP . Mike-up Wel1
Figure 1-2. L-P PLANT FEATURES
- 3 -
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OPHIR
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EXPLANATION
.~~~~(:t}t\~~:: Area of Concern
Figure 1-3. L-P LANDFILL FEATURES
- 4 -
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The L-P plant is underlain by two aquifers and an interven-
ing clay aquitard. The shallow aquifer that exists beneath most
of the northern half of the plant extends from ground surface to
depths of 20 to 40 feet. This aquifer is not present at the ad-
jacent Koppers site. Although the shallow aquifer probably ex-
isted prior to L-P plant operations, present water levels are
higher than w6uld naturally occur due to the sprinkler applica-
tion of water to the log deck. The permeability of the shallow
aquifer varies considerably laterally over the plant.-
Groundwater in the shallow aquifer appears to move both north and
west away from the recharge areas created by the ponds, the
boundary ditch and the almost continuous sprinkler irrigation of
the log deck. This aquifer is not currently used as a source of
water supply.
The regional aquifer extends to depth greater than 300 feet
beneath the L-P plant, and it is also present beneath the Koppers
site and the L-P landfill. Groundwater movement in the regional
aquifer -is generally due south. This aquifer serves as a current
source of drinking water.
The entire L-P plant is underlain by dredge. tailings
deposited during gold mining operations in the early 1900s. The
tailings consist of unsorted cobble gravel, sand, silt, and clay
derived from dredging of the-floodplain alluvium. The dredge
tailings, which may be as deep as 30 to 45 feet, constitute the
shallow aquifer. Beneath the dredge tailings lies older alluvium
of similar composition that was deposited by the ancestral
Feather River and which constitutes an aquifer of regional ex-
tent.
Land use in the vicinity of the site is mixed agricultural,
residential, commercial, and industrial. One- to five-acre farms
exist, and much of the produce and livestock is raised for home
use and not sold commercially. Residential areas are located to
the south, southeast, west, an~ northeast of the site. Three
schools are located- within a two-mile radius of the site.
2.0
SITE HISTORY AND ENFORCEMENT
Dredge mining for gold in the Feather River basin- began
around the turn of the century. The Louisiana-Pacific plant area
and environs rest on tailings created by the dredger mining ac-
- 5 -
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tivities. In 1929, a San Francisco-based mining firm, Natomas
Company, purchased the land around the present L-P site from
several individuals, and continued dredge operations until 1936.
At that time, Butte County issued regulations requiring replace-
ment of topsoil. From 1936 until 1969, no organized dredging ac-
, tivity occurred at the L-P plant area or environs. Georgia-
Pacific Corporation purchased the present L-P site in 1969 and
completed construction of the sawmill facility in 1970.
Louisiana-Pacific Corporation took control of the property in
1973. The hardboard facility was constructed in 1973 and the
landfill began operations in 1978.
Between 1970 and 1984, a fungicide spray containing pen-
tachlorophenol (PCP) was used to prevent fungal discoloration of
sawn lumber. In 1973, a state agency discovered PCP contamina-
tion in local groundwater south of the L-P plant. Since 1973,
state agenci~s have monitored the L-P site, and have detected PCP
contamination in surface water, sawdust, and wood waste at the
plant and landfill. As a result of this evidence 'and their use
of PCP, L-P was suspected of being partly responsible for the PCP
contamination discovered in 1984 in groundwater south of the ad-
jacent Koppers site. In May 1985, the California Department of
Health Services requested that EPA take over as lead agency at
the L-P site. In February 1986, the L-P site was placed on EPA's
National Priorities List (NPL). In December 1986, following un-
successful RIfFS negotiations with L-P, EPA began remedial inves-
tigations of surface wat~r, soil, sediment, groundwater, wood
waste, and air at the L-P site for evidence of contaminants. EPA
issued a Remedial Investigation (RI) Report in January 1989.
Concurrent investigations of air quality were conducted by L-P
and the Butte County Air Pollution Control District over a one-
year period beginning in 1988. An Endangerment Assessment Report
on risks from the L-P site was issued by EPA in September 1989,
and a Feasibility Study (FS) Report was. issued in May 1990.
. Results of the EPA investigations have shown that
groundwater, surface water, soil, sediment, and wood waste con-
tain various contaminants used by L-P and Koppers. Concentra-
tions on the L-P plant were found to be highest in an area along
the L-P/Koppers boundary. contaminants in this area will be ad-
dressed as part of the Koppers cleanup. Elsewhere on the L-P
plant, only, arsenic (in surface soil and shallow groundwater) and
formaldehyde (in groundwater and air) were found at concentra-
tions high enough to be of potential concern to public health.
- 6 -
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Although PCP was detected in surface and 'subsurface soils,
surface waters and groundwater at the L-P site, the concentra-
tions were so low as not to pose a significant threat to human
health and the environment.
Correspondence between EPA and L-P can be found in the Ad-
ministrative Record for this site, an index of which is attached
to this Record of Decision.
3.0
COMMUNITY PARTICIPATION
The EPA has encouraged pUblic participation throughout the
RI/FS process, in accordance with CERCLA requirements.
Fact sheets were sent out to the public at key progress
points in the investigation. Technical exchange meetings were
held monthly or bimonthly at L-P during the field work phase of
the RI, and representatives of public agencies and local citizen
groups were invited to attend. RI/FS documents, including the
Remedial Investigation Report, the Endangerment Assessment
Report, and the Feasibility study Report, were sent to local
libraries and a representative of a major community group.
Public participation requirements for EPA's selection of the
remedy as defined in CERCLA sections 113(k) (2) (B) (i-v) and 117(a)
were met by the activities described below.
The proposed plan was distributed using EPA's mailing list
for this site. A public comment period on the proposed plan was
held between May 14, 1990, and June 13, 1990. Public notice was
provided prior to the opening of the public comment period, and
this notice appeared in three local newspapers including the
Oroville Mercury-Register. Briefings on the proposed plan were
given to representatives of community groups and elected offi-
cials on May 15, 1~90. In reporting on these briefings, the
press advertised the proposed plan and public comment period. A
formal public meeting was held on May 22, 1990. A transcript of
the meeting can be found in the Administrative Record for this
site.
The attached response summary provides EPA's responses to
written comments submitted durin~ the public comment period and
to comments made during the May 2~, 1990 public meeting which
were not responded to during the meeting.
- 7 -
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4.0
SCOPE AND ROLE OF DECISION
There are no current uses of the site which pose a sig-
nificant risk to human health or the environment. However, fu-
ture residenti~l use of the site and/or domestic use of the shal-
low groundwater at the L-P plant or regional groundwater at the
L-P landfill could pose an unacceptable health risk. Therefore,
EPA is selecting interim remedial actions to address these poten-
tial future risks posed by contamination in surface soil and
groundwater at the L-P site. These actions are EPA's first
remedial activities at the site.
The risks of potential human exposure to surface soil at the
L-P plant and groundwater at the plant and the landfill exceed
the threshold level of concern. However, additional information
is needed to resolve uncertainty about the existence of formal-
dehyde in groundwater and the background concentrations of ar-
senic in soil and groundwater.
Additional information is necessary to fully evaluate the
relative risk posed by arsenic and formaldehyde contamination at
the site. Arsenic is a naturally-occurring element in soil and
groundwater, and background concentrations have not been ade-
quately determined for the L-P site. The concentration of ar-
senic in soil on the log deck appears to be slightly elevated in
comparison to the estimated background level for this area. The
presence of formaldehyde in groundwater at the plant and landfill
has not been conclusively established, and consequently addi-
tional monitoring is needed. It is therefore not possible at
this time to set remediation goals or select final remedial ac-
tions for the site.
In the interimf while additional information is being
gathered and analyzed, the selected remedial actions are neces-
sary to prevent the routes of exposure which create potentially
significant risks. Specifically, EPA's chosen interim remedy for
surface soil employs institutional actions to prevent exposure to
contaminated surface soils at the L-P plant. By eliminating the
possible exposure pathway created by unrestricted access to and
use of' the site, the selected interim remedial actions control
the health risk posed by arsenic contamination in the plant
soils.
- 8 -
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The interim remedy for groundwater also employs institu-
tional actions to prohibit domestic use of shallow groundwater on
or near the L-P plant and regional groundwater at or near the L-P
landfill. A ~onitoring program will help to define the back-
ground levels of arsenic in groundwater, the areal extent of con-
taminated groundwater and will also indicate any changes in con-
taminant l~ve~ that might influence the selection of a final
remedy for the site. In addition, as part of the Koppers
cleanup, the use of any wells by L-P or others that interferes
with containment or cleanup of the regional aquifer will be dis-
continued and an alternative water supply will be provided. .
5.0
SUMMARY OF SITE CHARACTERISTICS
5.1 Potential Sources of Contamination
Potential sources of contamination at the L-P plant and
landfill include the discharge of wastewater and plant process
wastes from L-P and contaminants migrating from the adjacent Kop-
pers site.
5.1.1 Wastewater. Wastewater produced during. plant processes
was discharged prior to late 1988 to a surface pond called the
western sump (Figure 1-2). High levels of formaldehyde reported
in the sump water were traced to the hardboard plant glue kitchen
where a urea-formaldehyde resin was prepared for use in manufac-
turing hardboard. Formaldehyde entered the wastewater in wash-
water from the concrete floor of the glue kitchen. Discharge of
this washwater was discontinued in October 1988; the washwater is
now recirculated in making hardboard.
5.1..2 Process Wastes. Process wastes are released from the L-P
plant as sawdust, dust, boiler ash, and wood debris from the log
decks. In addition, plant processes release formaldehyde vapors
and dust during the hardboard manufacturing process. Sawdust and
wood debris are disposed of at the landfill. Boiler ash is dis-
posed of in trenches at the southeastern edge of the landfill.
Dust, including particulate emissions from the hardboard plant,
may be transported in air to off-site receptors, or may settle on
plant roads and then may be re-suspended by wind or vehicular
traffic. Dust emissions from the unpaved log deck areas are con-
trolled by water from sprinkler trucks.
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5.1.3 Miaration of Contaminants from the KODDers site. Inves-
tigations by Koppers at the L-P plant and by consultants to L-P
revealed that.contamination of the L-P plant area has occurred
due to the proximity of the L-P and Koppers Company plants, and
water-use practices on the L-P plant. .The soil and.groundwater
beneath the Koppers site is cont.aminated with wood treatment
chemicals used by Koppers, including PCP, isopropyl ether,
polynuclear aromatic hydrocarbons (PAHs), arsenic, chromium, and
copper.
The L-P/Koppers drainage ditch runs between the two
properties and receives surface run-off from the Koppers property
and overflow from the Koppers fire pond. The ditch also receives
seepage from two areas on the western edge of the Koppers
property where unlined surface impoundments were formerly used to
store or dispose of chemicals: the creosote pond and Cellon
blowdown discharge areas (EPA ,1988d). Creosote was shown to ex-
ist as an oily phase in the soils in the former creosote pond
area, and to have migrated through the vadose zone onto the L-P
property. The Cellon process at Koppers involved use of a mix-
ture containing PCP, .isopropyl ether (IPE), diesel oil and li-
quefied butane. These chemicals have been detected in high con-
centrations in the L-P/Koppers ditch sediments and surface water.
Water in the ditch flows south to the L-P log deck pond.
Chemicals. from the creosote pond and Cellon discharge area
have been shown to have contaminated the regional aquifer beneath
both the L-P and Koppers sites. Groundwater from this regional
aquifer is pumped from three active wells on the L-P site: the
make-up well, the boiler well, and the electric fire well (wells
MUP, BRL, and EFW in Figure 1-2). Pumping ~fthe electric fire
well causes movement of groundwater towards L-P from the Koppers
site, and creosote and Cellon products have migrated towards the
L-P property in response to this pumping. Water from the
electric fire well discharges directly i~to the L-P/Koppers .
drainage ditqh and flows to the-log deck pond. PCP and IPE have
been measured in the electric fire well at levels as high as 200
parts per billion (ppb) and 1,050 ppb, respectively. Use of this
water to spray the log decks may have contributed to surface con-
tamination at the L-P site.
Groundwater pumped from the L-P make-up and boiler wells is
fed into the plant process distribution pipeline and boiler,
respectively. PCP levels in the make-up well (typically less
than 1 ppb) have not been significant, as it is farther from con-
. - 10 -
-------
tamination sources than the boiler well. Levels of PCP as high
as 94 ppb have been measured in the boiler well. From the
boiler, excess water is discharged to the wastewater pipeline
which leads to the western sump.
The log deck pond received water from the L-P/Koppers ditch
and from other portions of the Koppers site~ Levels of PCP in
Koppers run-off into the log deck pond have been as high as 430
ppb but have typically been measured at levels closer to 50 ppb.
PCP levels in the log deck pond itself have ranged from 2 to 260
ppb. Water pumped from the log deck pond may have led to or-
ganics and arsenic contamination of the L-P site soils and under-
lying groundwater via the following cycle. Water is pumped from
the log deck pond and is spread over the plant by: 1) sprinkler
trucks for dust control ,and 2) sprinkler irrigation of log piles
to reduce fungal discoloration of the wood. Excess water col-
lects on the surface and may flow back to the log deck pond or
infiltrate and recharge the shallow aquifer groundwater.
5.2 Nature and Extent of Contamination
site characterization activities during the remedial inves-
tigation involved sampling and chemical analysis of soil,
groundwater, surface 'water, sediment, and wood waste at the L-P
plant and landfill, and vapor and airborne particulate matter at
the plant.
Based on the past history of chemical use on the L-P
Koppers sites, as discussed in Section 5.1, the following
cals were initially selected for analysis:
and
chemi-
o Pentachlorophenol (PCP)
o Isopropyl ether (IPE) ,
o Polychlorinated dibenzodioxins/dibenzofurans
o polynuclear aromatic hydrocarbons (PAHs)
o Arsenic
o Boron
o Chromium
o Copper
o Mercury
o Formaldehyde (HCHO)
o Petroleum hydrocarbons
o Volatile and semi-volatile organic compounds
(PCDDs/PCDFs)
Of these chemicals, L-P is known to have used PCP and formal-
dehyde.
- 11 -
-------
In analyzing for these chemicals and a wide range of other
organic and inorganic chemicals in the various environmental
media, a large number of chemicals were detected. Chemical con-
centrations were then evaluated using four criteria (background.
concentrat~on~; blank concentrations; frequency of detection; and
historical use, concentration, toxicity and physiochemical
properties) in order to focus the risk assessment on those chemi-
cals that are most likely to pose risks at the L-P site. The
resulting subset of 38 chemicals of potential concern for each
medium are shown in Table 5-1. Concentrations of the chemicals
that were detected in each medium and used to determine site
risks are shown in Table 5-2. In addition, formaldehyde was con-
sidered to be a contaminant of potential concern in air, based on
analyses of vapor and particulate formaldehyde emissions from the
hardboard plant and based on analyses of surface dust.
6.0
SUMMARY OF SITE RISKS
The risk assessment (conducted as part of the Endangerment
Assessment report) documents the potential risks associated with
the L-P site. The major steps in the risk assessment process are
identification of contaminants (see Section 5.2), exposure as-
sessment, toxicity assessment and risk characterization. The En-
dangerment Assessment (EA) is included in the Administrative
Record.
Neither the RI nor the EA characterized fully naturally oc-
curring or "background" l~vels of arsenic in soil. Arsenic con-
centrations in soil are to be expected because this element oc-
curs naturally in soil and rock. This naturally occurring con-
centration is referred to as the background concentration. A
limited number of S9il samples from soil boring P-1 were used to
represent background, based on t.he location of this boring at the
northern edge or the L-P plant. Arsenic levels in these samples
were 2.5 mg/kg. However, the limited number of samples does not
provide an adequate statistical base for determining' if the dif-
ference between background arsenic levels and those in on-site
samples is significant. Another estimate is provided by analyses
of soil samples collected in the United States (Shacklette and
Boerngen, 1984). Arsenic is reported to range from less than 0.1
to 97 mg/kg in the western U.S. and ranges from 1.8 to 4.5 mg/kg
at two sample locations in Butte County.
-.12 -
-------
Page 1 01 2
Table 5-1
Chemicals of Potential Concern at the Louisiana-Pacific Site
PLANT LANDFill PLANT lANDFILL SEDIMENTS SURFACE SURFACE
SOILS SOILS GROUND- GROUND- WA TEA DUST
ChemIcal WATER WATER
Ac8Cone X
Benzoic AcId X
b8Ia-8HC X
BII(2~pbhIIM. x
2...... X
~~. X
CNordIne X
DkHx:Iyt phIh8IMe. X x
...... ~ benzene X
w FOIINIIdIIt¥i8 X X X X X
2-H8can0n8 X
IIoprOf¥ 8Ih8r X
MeIt¥8n8 chloride X X
.. U8d¥-2~' X
2-, end~ X
PAHa X X x
PCD08JPCDFs x x x
PerucIDopheooI X X X X X X x
Phenol X
Slyrene X
TelrachkJro8lhene X
Telr8ChlorophenolS (T0IaI) X X
Toluene X
3.4.5- Trict*xopheno8 X
-~_. -_._-
-------
Pago 2 01 2
Table 5-1
Chemicals of Potential Concern at the Louisiana-Pacific Site
PlANT
SOILS
LANDFILL
SOILS
PlANT
GROUND.
WATER
LANDFILL
GROUND.
WATER
SEDIMENTS
SURFACE
WATER
SURFACE
DUST
ChemIcal
ARknofrt X
Ar8enIc X X X X
B8Un X X
! I Befy8um X X X
t-' Boron X X X X X X
.".
CtvomUn X X X
Copper X X x x
Lead X X X
M8ng8n88e X X X X
Mercury X X
Nick8I X X X X
SIller X X
VINIdIum x
Zinc X X X X X X
-------
Table 5-2
Concentrations of Chemicals of Potential Concern
PI....t Surface Soi I landfill Surface Soil
Ch88lcIII Geo. Me.... "IX. Geo. Me.... Mex.
GIIAIICS CUI/ltg) Cue/ltg) Cue/ltg) Cug/ltg)
ACE'. 4,400 7,300
_IIOIC ACID (I) CI)
IIICZ'I'I'llElYl) "'IALAIE
Z-..,.. C.I) 5,800 13,000
I
IUTIL _un "'IALA'E 200 460
be. 2.6 2.6
ca...- CI) CI)
DI-I-ac"l "'IALA'E CI) CI)
EIlIl _IIZEIE 1,600 2, UIO
f....l. 4,200. 7,900 11,000 ZO, 000
..... . Z-IEX" CI) CI)
lJ1 I...,l lllEl'
I .'IILEIE ca.IDE 12 44 1,600 1,600
4..'"L-Z''''IAIDIE CI) CI)
'..'"L 'lED Co-ell"'. n n
4-.Iln PIER Cp-eII.... 160 160
,All - CAlCI...IIC
,All - ...I...IIC 1,240 1,240
PCIIOl/fCDfa ClEa. - EPA 0.0029 0.051
PCIIOI/fCDfl CIEa. - II'EIlAIIOIAL CO.021) CO.22)
PU'M:lLCllClPlED 12,000 12,000 CI) CI)
"D CI) CI.
I"UII CI) CI)
'IIIACILCIIOE llElE CI) CI)
IEIUCIU...IEDI (tOTAL) CI) CI)
IGLUE. 4,400 16,000
1,4,S-IIIClLOIOPIEIOL
Page 1 01 6
Plant Surface Oust
Geo. Mean MaA.
Cue/kg) .
(ug/kg)
890 2S,OOO
..
52,000 130.000
41,000 34Q.OOO
730
0.00019
(0.0012)
130
6,100
0.0Q6I.
(0.027)
400
CI) . Selaeted.. I cheal'll of potent ill concern ba5ed on iu detection in 5~urface 50115 . not detected in surface sOils.
C .. Concennlti- of PCOO./PtOh in perenthuu were calculated using International TEh.
concentretl- of PCOOa/peOfs without perentheses were calculated using EPA IEfs.
-------
Table 5-2 Pago 2 016
Concentrations of Chemicals of Potential Concern
raent SurfKe Sol' LendflH SurfKe SoH Plant Surface Dust
CII88'u'. Geo. "'en ..... Geo. "'en Max. Geo. Mean "a~.
1_ICt (111/\[8) (111/118) (111/\[8) (111/\[8) (l1li/1111) (1III/k\l)
MII- 28 49
MlDIC 5.6 1)
-"II
_YLL..II I.S S.1
- 18 5l 27 69
C8IIltM 41 150
...... 14 550 55 44
LUD
..... 500 1,100
I .1Q8,
...... IICIIL 87 150 110 160
0'1
I Ill..
VAIMIltM
ZIIC 110 2SO 4S 45 U 2~O
.-.-----______h_. -
-------
Table 5-2
Concentrations of Chemicals of Potential Concern
Pilgo3016
ClM8lcal.
Off-.it.
Pond ledi8lnt.
(L -P II O.t.)
&eo. 118- .....
L-P Off-.lte Ponds
led I...,..
(0.... & Moore dat.)
Geo."'- Mu.
loP log Oeck" Pond
Sedillleni s
(l-P RI Oala)
Geo. Mean
Mall..
CIIGAIIICI
(ue/llt)
hl8/IIII)
(ug/llt)
(Ullllt)
(118/1111)
. (ug/kg) .
I
t-'
-..J
Gr.
RIIlOIC AtID
IIIU.£tllYl.nu ..tiALAtl
2-IUtUOllE (.1)
IUIYl IElIln PltllAlAtE
betIC
ca....
DI-l-oe"l "'IALAtE
ErIYl .IZE.
fGMM.D(1.
2-.'"
I....UII.I
4-.'''L-2-PEI'UOIIE
.'''WE ca.IDE
2-.Jln PIE- (o-ClfSOl)
4-.tIlL ...... (p-ClfSOl)
,All - CAlCI..IIC
,AlII - IIIItAICI..IIC
PalDllPCDf. (tEa) - E'A
PCDDI/PCDf. (tE8) - II'EI..IIOIAl
PEI'acaCllCl'''
PIE-
InH.
IUU£IlCIICIE'..
IUU£IILCIIOP....S (lOtAL)
tOUIE.
J.'.5-IIICllLCIIOPIE'"
~.2 1.0
0.025 0.028 0.0014 0.18 0.]1 0.4'
(0.21) (0.28) (0.049) (0.29) (1.2) (1.1)
54 510 ZJ 470 1.000 6,200
..
( ). concentr.tlonl of PtDO./PCDf. in p8renthel.. were c.lculated using InternatiOO8I IEf5.
Concentr.tlonl of PCOOs/POD'. without p8renthe5e. were calculaled using EPA fEfs.
-------
Table 5.2
Concentrations of Chemicals of Potential Concern
Pago 4016
Ch88lce&.
Off-alt. Pond
SedlMnta
(LoP I' Data)
Geo. 11881'1 .....
loP loe Oeclt Pond
5ediMnt8
(0.... & Moor. data)
Gee». 11881'1 .... .
loP log Deck Pond
Sed i 8leo(f,
(l-P I' Data)
Geo. Me8l'l
"811.
I_ICI (111/111) (111/111) (111/111) (111/111) (111/111) (IIII/kll)
alii 1-
....IC 47 86 9.8 56 ]5 41
UlI&II
.nUI&18 5.0 5.0 1.5 1.5
- 450 980 200 250
CI8II1&18 n 95 57 95 560 2,100
c; .awu n 88 22 49 220 610
LEAD SO 65 JO ~1
...-
1BCI8' O.SO 0.96 1.] 1.}
IICIIL 150 240 94 ISO
IIL-
vAllDna
IIIC 160 590 ,,- 180 2}0
-------
Table 5-2
Concentrations 0' Chemicals 0' Potential Concorn
OM8lc.'1
Plent .
Gr""'ter
G8O. lteen .....
l8ndfitt
Gr""'ter
Cleo. lteen flu .
CllCiAIU CS
(ug/U
(ug/l)
(ug/L)
(ug/L)
.....
\0
aal.
..mlle ACID
111(2-II'YLIE.YL) PlIIALAII
2-"1'- c.'') I
MIL MUll ..IIIAlAII
b-IIC
c:a~
DI-.-acl'L ..IIIAlAIE
IIIIl MIZEIE
.C8MI.DEIYDE
'-II'"
I""'&' .111.
.lInllE ca.IDE
4-.1"&'-2-'111'-
'-.IIIl ... Co-CIlia&.)
4-.IIYL MIDL Cp-ClEIa&.)
NIl - CMCI..lle
NIl - 1CIICMC1..lle
PCIIDII'CD'I (lb) - I"
PCIIDII'CD'I (III) - IIIEIlAII01AL
'IIM:aCIIGPIiIDL
...
'''.11
IEIIAC1LOIOEIIEII
IOLUlIE
IUWILCllGPlEIDLS (lOTAL)
. 3.4.S-TI'CIL0I0P1E1DL
3.2
100
6S0
18
4S
8.4
12
0.63
0.84
1.1
( ). Concentr.tlona of PCODI/PCOfl In parentheici werc c.lcul.t~ using Internetionet 'Efl.
Concentr.tlona of PCOOI/peOfl without parenthclci were c.lcut.t~ using EPA 'Efl.
Pilgo5016
-------
Table 5-2
Concentrations of Chemicals of Potential Concern
Page 6 01 6
,t....i
Grcu-..ter
Geo. ....... Mall .
Und'itt
Grcu-..ter
Geo. ....... .....
N
o
I
AlfllIIIY
AllUIC
......
.'U'IM
-
C8IIIIIM
CIIIffII
LUD
.......
....,
I.CIIL
IILVII
....IM
II.
(ueJL) (ueJL)
5.9 )9
110 2SO
700 850
(ueJL)
( ueJL)
1.5
5.7
110 9,500
8.) 60
61 520
4.8 6.)
41 160
1,700
J,9OO
-------
Background levels of arsenic in groundwater also were not
characterized in the RI.
In the absence of a more complete characterization of back-
ground levels. of arsenic, EPA cannot assess the risk posed by the
site to human health and the environment. In addition, without
establishing background levels for arsenic levels in the soil and
groundwater at the site EPA cannot fully evaluate remedial alter-
natives.
In addition, there is a high degree of uncertainty as-
sociated with the presence of formaldehyde in groundwater samples
taken during drilling, as field blanks collected on the same days
as samples from five of the six sample locations were found to
contain formaldehyde concentrations ranging from 16 to 48 ~g/L.
Furthermore, formaldehyde was not detected during monitoring at
these same drill hole locations after well construction, well
development, and purging. Therefore, additional monitoring is
necessary to conclusively establish the presence or absence of
formaldehyde. If formaldehyde is not present in groundwater, the
only contaminant of concern is arsenic. If formaldehyde is
present, EPA may con?ider the cumulative risks posed by these two
contaminants in selecting remedial actions for the site.
The EA did, however, id~ntify potential risks associated
with exposure to contaminants at the site at the levels detected
during the RI. The procedures used to identify these risks are
described below.
Under the EA, the potential pathways of human exposure to
contaminants of concern on the L-P site were identified and
divided into five current-use and eight future-use exposure
scenarios. These scenarios are described in Table 6-1. The fu-
ture use scenarios assumed the highest use of the property or
"maximum exposure use scenario" -- residential use of th~ plant
and landfill and use of the shallow groundwater (at the plant)
and regional groundwater (at the landfill) as sources of domestic
water supply. EPA evaluated the use associated with the highest
(i.e., most significant) risk in order to be protective of human
health. EPA believes that at this time it is reasonable to
evaluate such risks based on currently available information.
Exposure was assessed for both an average case and a maximum
plausible case for each exposure scenario. For the average case,
geometric mean concentrations are used, together with what are
- 21 -
-------
Page 1 of 3
Table 6-1. SUMMARY OF POTENTIAL HEALTH RISKS IDENTIFIED BY THE
ENDANGERMENT ASSESSMENT: lOUISIANA-PACIFIC SITE8
N
N
Total Upperbound Non-Carcinogenic Chemicals with Chemicals wllh Total Upper-
lifetime Excess Hazard Index Hazard Index bound lifetime Excess
Exposure Cancer Risks (CD' : AID) > 1 Cancer Risks
Pathway
Scenarios > 1 x '10- 6 >1X10-4
Average Maximum Average Maximum Average Average Maximum
Exposure Exposure Exposure Exposure Exposure Exposure . Exposure
-
Current Use:
CU1 Exposure 01 Aduh Trespasser to . 2 x 10- 11 2 x 10-8
-------
Page 2 01 3
Table 6-1. SUMMARY OF POTENTIAL HEALTH RISKS IDENTIFIED BY THE
ENDANGERMENT ASSESSMENT: LOUISIANA-PACIFIC SITE a
I
tV
lA)
Total Upperbound Non-Carcinogenic Chemicals with Chemicals with Total Upper-
lifetime Excess Hazard Index Hazard Index bound lIletimo Excess
Exposure Cancer Risks (CDI : RID) > 1 Cancer Risks
Pathway
Scenarios > 1'x 10-6 >1x10-4
Average Maximum Average Maximum Average
Exposure Exposure Exposure Exposure Exposure Average Maximum
Exposure Exposure
Future Use:
FU1 Exposure of Child Resident to 4 x 10-6 4 x 10- 5 < 1 .1 Arsenic
Onshe Surface Solls-Plant (4 x 10- 6) (7 x 10- 5) « 1) (> 1) Arsenic
. ---.-..- ----.... f--.-----..-'.."." ._'-~......-.' .. ..~.~ ."..,.",.~...
FU2 Exposure of Child Resident to -9 4 x 10-8
Onslte Surface Solls-Landlnr 6 x 10 < 1 < 1
--"..--. . --.---- ..--.---.............",,--- _...........~.........~..._........."".__... ,-"''''',,,,,'_,,',-'''',''-,,,,,,,,,,_'-~,'''''''-'''''. ...-...",..-.",- .......-''''''..~'........... .-..- ,'.....-.- ....''''''" ..
FU3 Exposure of Child Resident to -7 -6
7 x 10 -6 9 x 10 - 5 < 1 < 1
Log Deck Pond Sediments-Plant (1 x 10) (3 x 10) (<1) (> 1)
[[["''''''''''''''''''''''''.''''''''','''' ................................,.,- """"'0""""""""".'''''''- ..........,......".,....."........ .,...............,..,.....,.......... ....... ............
FU4 Exposure of Adult Resident by -5 9X10-4
Ingestion 01 Shallow Ground- 2 x 10 <1 .1 Arsenic Arsenic
water-Plant
"""~",,,---,"'. -'-""""-'''''''''--'''- -..--..-.- --".-._---_............._-...-. f---........... . .'..~'.. ........ '~'" ..'.ro'..'.'.'...-..... ........
FU5 Exposure of Aduh Resident by -5 -4 HCHO
-------
Page 3 of 3
Table 6-1. SUMMARY OF POTENTIAL HEALTH RISKS IDENTIFIED BY THE
ENDANGERMENT ASSESSMENT: LOUISIANA-PACIFIC SITE-
IV
.".
I
Total Upperbound Non-Carcinogenic Chemicals with Chemicals wllh Total Upper-
Uetlme Excess Hazard Index Hazard Index bound lifetime Excess
Exposure Cancer Risks (CD I : RfD) > 1 Cancer Risks
Pathway
Scenarios > 1 x ,10- 6
Average Maximum Average. Maximum Average > 1 x 10- 4
Exposure Exposure Exposure Exposure Exposure Average Maximum
Exposure Exposure
.
Future U..: (continued)
FU6 Exposure of Aduh Resident by 2 x 10-8 2 x 10-7
Ingestion of Regional Ground- <1 > 1
water-landflU
-'-'._~ "'-..--. ". --_.......-.._-~-----_.. '''''''-'''''-----' -'_.--.............'.n.'......_....n....... ,~".'.........., ........
FU7 Exposure of Aduh Resident by
Inhalation of Volatilized Organics 5 x 10- 6 4 x 10- 5 -- -- HCHO
from Regional Groundwater-
landfill
.,.n"u""'n~~_''','~-''''--'''''''''''''''''''' "."""""--""--"""''''''--''''''-'' ."......-......... --""""""""",,'.........nu"'''''''''''''' ,,,,,,.,,,,,,,,,,.,,,,,,.,,,,,,,,,,u,,,,,....-.......u ""............U...n................... ""'.'-."##U..O'".'''''''''''''''##''' '__""0"-'''''''''''''''''''''''''' ...- ',-,"..''''''''
FU8 Exposure of Adult Resident by 4X10-7 3x10-6 <1 <1
Inhalation of Onshe Dust-Plant (4x 10-7) (3x 10-6) « 1) « 1)
CDI : RfD Chronic Dally Intakes Reference Dose
No chemical whh non-carcinogenic toxici1y cri1eria were
evaluated for this exposure pathway.
HCHO
(4 x Hr. 7 )
Formaldehyde
a
Based on Table 0-1 (Clement 1989)
Potential risk values In brackets were calculated using Internallonal
method for calculating 2, 3, 7, 8 TCDD equivalents.
These values are not used by EPA to assess risk but are Included
as a check on the unbracketed values-
<
Less than
>
Greater than
-------
considered to be the most likely exposure conditions. For the
maximum plausible case, the highest measured concentrations are
generally used, together with high, although plausible, estimates
of exposure parameters such as frequency and duration of exposure
and quantity of contaminated media contacted. The exposure as-
sumptions arede~cribed in detail in the EA.
The toxicity assessment looks at both carcinogenic and non-
carcinogenic effects of chemicals present at the site. Cancer
Potency Factors (CPFs) are used to estimate excess lifetime can-
cer risks associated with exposure to potentially carcinogenic
chemicals. CPFs are derived from the results of human
epidemiological studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been
applied.
The potential noncarcinogenic effect of a single con-
taminant in a single medium is expressed as the hazard quotient
(HQ), the ratio of the estimated intake to the contaminant's
reference dose. The reference dose (RfD) is an estimate of the
maximum human chronic daily exposure level that is likely to be
without deleterious ~ffects during a lifetime.
The last step in the risk assessment process is risk charac-
terization, when information from the preceding steps is combined
to determine the risks assoclated with the current and future use
scenarios. In this case, the risk characterization step involved
calculating the potential risks posed by arsenic and formaldehyde
in soil and groundwater at the concentrations detected during the
Remedial Investigation.
For cancer risks, CPFs are multiplied by the estimated in-
take of a potential carcinogen to provide an upper-bound estimate
of the excess cancer risk associated with exposure at that intake
level. Cancer risks calculated in the Endangerment Assessment
are probabilities that are generally expressed in scientific
notation (e.g., 1 x 10-6). The term "cancer risk" as used in
risk assessment is an UDDer-bound estimate of the potential ~
~ cancer risk posed by exposure to contamination at the site
under the conditions of exposure specified in the risk assess-
ment. Therefore, a cancer risk of 1 x 10-6 means that exposure
to site-related contamination may increase an individual's
chances of developing cancer by as much as one-in-one-million
over the background cancer incidence. Since this is an upper-
bound estimate, the actual risk is likely to be lower and may
- 25 -
-------
even be a~ low as zero in some cases.
For non-carcinogenic effects, the Hazard Index (HI) is gen-
erated by adding the HQs for all contaminants within a medium or
across all media to which a given human population may reasonably
be exposed.. ~e HI provides a useful reference point for gauging
the potential significance of multiple contaminant exposure
within a single medium or across media. A hazard index of less
than or equal to 1 (~1) indicates that it is unlikely for even
sensitive populations to experience adverse health effects.
In the absence of certainty regarding the presence of for-
maldehyde, and without having fully identified background levels
of arsenic, it is not possible to characterize fully the risks
posed by the L-P site. Therefore, the results of the process
described above are estimated risks of exposure to soil and
groundwater. The estimated risk levels for each exposure pathway
are shown for carcinogenic risks (total upper-bound lifetime ex-
cess cancer risks) and for noncarcinogenic risks (Hazard Index)
in Table 6-1 for all current and future use scenarios.
6.1 Risk Levels of Concern
In general, risk levels of concern are those that represent
a significant potential threat to human health. As stated in
Section 300.430(e) of the National Contingency Plan (55 FR 8848) ,
acceptable exposure levels for known or suspected carcinogens are
generally those concentration levels that represent an excess
upper-bound lifetime cancer risk to an individual of between 10-4
and 10-6. For noncarcinogens, the acceptable exposure level is
generally one for which the Hazard Index does not exceed a value
of 1.
Exposure pathway scenarios at the L-~ site for which es-
timated risks exceed the threshold of 1 x 10-6 are shown in Table
. .
6-2. Of all the 38 chemicals evaluated in the risk assessment,
only arsenic and formaldehyde had concentrations high enough to
pose risks exceeding the levels of concern and thus be considered
for remedial action. .
6.2 Chemical Levels of Concern
For each of the five exposure pathway scenarios shown in
Table 6-2, a carcinogenic-risk~based "residual concentration" was
calculated for the average and maximum cases (shown in columns 6
and 7, respectively). These residual concentrations correspond
- 26 -
-------
Table 6-2. RISK-BASED RESIDUAL CONCENTRATIONS AND CORRESPONDING
SAMPLE lOCATIONS AND CONCENTRATIONS
Expoeur8
PBlhway
Scenarios .
CU5 Current
Exposure of Adult Resident by
Inhalalon of Hardboard Plant
Emiuians
Concentralion UsedinEAI
Corresponding Upperbound Canclnogenic Risk-Bued
Ufelime Excess Cancer Risk Residual Concentralions
Medium Chemical
and
Loc:allon (units) Average Maximum
AV8f8ge Maximum Exposure Exposure
Exposure Exposure Cancer Risk Cancer Risk
1x10 - 6 1 x 10- 4
All Offsi.. HCHO 7.811511 10-6 1.2
North of Plant (fIgIm3) - -
I
"""'0""""""""""""""'''''''''''''''''''''''','0'" .....................,....... .,.......,'n.",,,,,,,,,,, .......,...................... """"""""""""""'" """"""-"""""""" """"''''''''''''''''''''
FU1 Future
Exposure of Chitd Resident by
Conlad with Surface SoiI-Piant
Surt80e Soi
Plant
Atsenic
(mgIkg)
-8
5.614 x10
1.4
-
-
[[[ ............,...,............. ...........,......,........ """"""""""""""" """"""""""""""""""""..."'....."......... .............................
I
N
-.J
t
FU4 Future
Exposure of Adult Resident by
Ingestion of Shallow GIOundwater
Plant
.. '-_.' .._,,~..~..u~. .__#_~-~....._-~.~#,u"~-"-~",,,-.-_,,.....,--,
FU5 Future
Exposure 0' Adult Resident by
Inhalation of Volatilized Organica
!rom Shallow Groundwal8r-Plant
.......
"-...""..",,,.,,'.""""'.""."''''..'''''''.''''.
FU7 Future
Exposure of Adull Resident by
Inhalation of Volatilized Organics
Irom Groundwater-l.and1i1
Shalow
Ground-
wal8r
Aant
Arsenic
(J4g1l)
. '_......__n"'___-,,-'- ,,,,,,,,-,,..,,.......,,. '''' -_.-.,,#...,
Shallow
Ground-
wal8r
Plant
HCHO
(J&gIl)
-5
5.912 x 10
0.30b
4.3
HCHO
(J&gIl)
Onty exposure pathway acenarioa lot chemic:al concentraliona
which exc8ed a potential cancer risk of 1 x 1 r lot average
exposure, 1 x 10"'" lot maximum exposure, and an average
exposure hazard index of 1 are listed
a
39/9 x 10"'"
"''''''.'''.'-''-_._''-''~'''-..''#
'''----'-'''..'''.''','..--.....
b
These residual oonoentralions are below detection limits -
1.1 J4g1l 'or arsenic and 10 J4g1l 'or HCHO
"_.'.'.'.._-~......'_."'..........'.'''''._' ........
"'..""""""-'''-''.''
- Conoonlratlon lele88lhan the threshold level 01 concern;
ie, < 1x 10 ~ lor 8verege exposure, < 1x1~
lor maximum exposure
100/2 x 10-5
5b
650/3 x 10"'"
217
...............'"
...................
",.....""""""""'..'" '.'."""'"'''''''''''''' [[[
Regional
Ground-
waler
Landfil
............"''''''''
1815 x 10-t
3.6
-
-
7.81
Concentration used in EA to calculate potential health risk
J6 x10-t Ufetime upperbound exoess cancer risk corresponding 10
concentration used in EA
J
Estimated concentration
L
Resull is greater than or equal 10 method detection limil but
leu than conlracl required quanillalion limit
HCHO Formaldehyde
Sample NumberlConcentration (depth or location)
> Risk-Based Residual Concentration
Average
Exposure
01 three locations only the
predominant wind direction
10 the north exceeded
. residual concentration
..................
........
",,,,''''''
........
All samples analyzed!
Range 2.2-12.6
"""'......""'..-..
.......
All samples analyzed!
Range 1.9JL-38
"'.........,-..---' .
"-'..
... .
All samples in which
it was detected/Range
17J to 650J
.......
......'
W-2Al14 (150 II)
W.2A127(185 II)
W-3B/45 (209 It)
M,lximum
-------
to the conqentration of a contaminant that would pose either a
1 0-6 1 1 -4 .
X 1 or a x 0 cancer r~sk for the average or maximum
plausible exposure case, respectively, in each scenario. The
residual concentrations represent levels above which a chemical
in a specific medium may pose a potential threat to human health.
For each of the exposure scenarios, existing concentrations
of the chemical of concern were compared with the residual con-
centrations; those where the residual concentration was exceeded
are shown in the last two columns in Table 6-2.
Arsenic concentrations in soil and shallow groundwater, and
certain physical and chemical characteristics of groundwater at
the plant, are presented in Tables 6-3 and 6-4, respectively.
Maps showing the sample locations and concentrations of arsenic
and formaldehyde in surface soil and shallow groundwater at the
plant are presented in Figures 6-1 through 6-3.
The five exposure pathway scenarios in which chemical con-
centrations are estimated to pose a cancer risk to human health
in excess of 1 x 10-6 for the average. exposure case are discussed
in the following sections.
6.3
EXDosure to Hardboard Plant Emissions (CU5)
. Under current-use scenario CU5 (exposure of an off~site
adult resident by inhalation of hardboard plant emissions that
migrate off-site), concentrations of gaseous formaldehyde in air
at three locations near the L-P plant were evaluated in the risk
assessment. The concentrations of gaseous formaldehyde used to
determine inhalation risks at the three locations were based on
results of hardboard plant air sampling and air modeling. The
three locations were selected based on locations of residential
areas and meteorolo~ical data. These locations are:
o Trailer park west of the L-P site
o L-P property southern fenceline
o Receptor located north of the L-P
downwind direction.
plant, the predominant
The adult resident receptor north of
have a potential risk above the threshold
average exposure, based on annual average
the plant was found to
level of concern for
gaseous formaldehyde
- 28 -
-------
Table 6-3. ARSENIC CONCENTRATIONS IN SOIL AND
SHALLOW GROUNDWATER L-P PLANT.
Concentration in Soil a Concentration in
Sample Shallow Groundwaterb
Location Suriace Soil Subsuriace Soil LC = 0.30 ~g/L
mg/kg (depth) mglkg (depth) Monitoring Samples
lC = 1.4 mg/kg ~g/L (depth)
P-1 2.5.1 (2 ft) 10.3 (10 ft) NC
P-2 < 2.1J 22.8 (10ft) NC
P-3 9.8J (0 ft) 16.7 (5ft) NC
.,
P-4 12.6J ( 0 ft) 14.7(10ft) NC
P-6 NC 1.4LJ (10ft) NC
TP-1 3.2 (0 ft) 4.2 (5 ft); 4.1 (8 ft) NC
W-1 3.8 (2 ft) 11.6 (5 ft) NA
W-4 4.2 (0 ft) 2.9 (5 ft) 5.0JL (2~5 ft)
W-5 3.4 (0 ft) 4.0 (5 ft); 3.7 (10 ft) NA
W-6* 7.3J (0 ft) 78.5 (10ft) NA
W-7 * 10.8 (0 ft) 13.0 (5 ft) NA
W-8 2.2JL (0 ft) 3.7 (5 ft); 2.8 (10 ft) 2.8JL (14.~24.5 ft)
W-9 * 26.4 (0 ft) 22.5 (5 ft) NA
ML-1 NC NC 5.6JL (8-28 ft)
ML-3 NC NC 1.9JL (~29 ft)
ML-5 NC NC 38.0 (7-27 ft)
-
a Detection limit for arsenic In soil is 0.4 mglkg (ppm)
b Detection limit for arsenic in groundwater is 1.1 ~ (PPb)
LC Level of concern, based on average exposure scenarios
NA Not applicable; well taps regional aquifer
NC. Not collected .
J Estimated concentration
L Resun is greater than or equal to method detection limit but
less than contract required quantitation limit
* Sample loCated in the area to be remediated by Koppers
- 29 -
-------
Table 6-4. CERTAIN PHYSICAL CHARACTERISTICS OF
GROUNDWATER FROM PLANT MONITORING WELLS
Well No. Spec Boron Arsenic Temp Depth to Screen Aquifer
Condo . ij.Lg/L) ij.Lyt.) °c Wau:r (feel) Int.erval DcsignaLion
@ 25 0 C (feel)
ML-I 2,OSD . 725 @ 23 @ 6 - 30 ~
ML-2 680 482 <1.1 18 26.7 140 - 166 Regional
ML-3 690 702 @ 22 @ 8 - 31 ~
ML-4 650 445 <1.1 19 33.0 131 - 156 Regional
ML-5 670 .864 0 22 0 5 - 28 Cihallo~
ML-6 850 333 <1.1 19 36.9 64 - 79 Regional
ML.7 625 854 <1.1 21.5 22.1 18 - 43 Upper Regional
MW-20A 690 275 <1.1 20 36.7 72 - 82 BU'
MW .20B 600 531 <1.1 19 36.4 113 - 123 BL'
MW-21A 950 497 <1.1 16.5 30.4 78.5 - 88.5 BU'
MW-21B 680 338 <1.1 20 30.7 124. 134 BL'
MW-22A 590 614 <1.1 16 28.3 65.5 - 75.5 BU'
MW -22B 720 575 <1.1 17 27.1 120 - 130 B'
MW-22C 500 3,840 1.9JL 20.5 28.3 175.5 - 185.5 C'
W-l 720 1,170 <1.1 20 32.3 173.5 - 193.5 C'
W4 2,600 740 @ 21 @) 25 - 35 Q:ha110V
W-5 780 235. <1.1 19 33.6 121.5 - 139 Regional
W-6 610 233 - 1.2JL 20 '33.6 78-88 Regional
.
W-7 720 1,070 <1.1 17 30.2 43 - 53 Upper Regional
W~ 800 559 Q&1L ~ 23 @ 14.5 - 24.5 C!ha1IOV
W-9 700 577 1.91L 18 31:6 45 - 55 Upper Regional
c::> Significant informaIion from we11s tapping the shallow aquifer
B' Dames &: Moore designation far Regional Aquifer; U - Upper, L - Lower
C' Dames ~ Moae designation far Deep Regional Aquifer
J Estimaled concenuation
L Result is greater than or equalao the method detection limit but less than the contract required quantitation limil
-------
~
....
r
~
r--------- - - ~ - ----- --------~
!
P,'92,5J)
EXPLANATION
I
,/ ---!
-..-- ;'
'-
I
I
: ,/ ....
, .'
---
,i
W.8 '
..2(2.2JLi
-. - ~'O- 1--
(~.-~-.
, ~3r~ (3.B}j' : I
i- r\:''.- -...,- ..J" , -, . , I
,I , ,., :
~' =::... i ii «2ij~t~__- ! '- -----.--Ir~ 'O'19_8JI ?:.:~ :~/ - .-.
,I ' ,O(NC) I.
ill ,,' '~', ~._..rL.........J P-6 ;
: II w~<:21 '-'-______m----___n_m__n__n__n - - - J:~
, ;1 0' .. .. . ',,,,- W-6. - - j
J Estimated ! 1,1 ('"\ "'," '," LOUISIANA-PACIFIC (7.3J~r-'"
conc»ntration I;,' PLANT I,
L R...RIs grwal8r ""I :"''- \ ", "Ii
Ihan or equal to ; 'II \., .', " // W.9d~
:'~I=;: III' I'~' ._--~\ ' (26.4)-1/:
contract rwqund ", i '".-:57 c,o.:J ~:'ECr< :" . :~S7:.OG :E~K J
--:;.:::~ ,f//:; '.,----j OP-4. " , II
wee, InIhotd , I i (12 6J) ':1 . .
lIweIaf-b i I,: . 'I Ii. -.'.
-*:1n1Ult8c8 'i , I 1;/
8OI1I,.4~ ! I':: TP.' W.7 . fi/,"
II~': ' (3.2)CJ 0.1: .{,r
.~CDIIOIIIt" if: (10.81 II .,:'~.
..... nollnc:tucl8d 'I i " / . '
In EA IIIk caIc:IIIIIion8 II.. : ~ : I!
'*--~.. lili ----',;' t(,? '-, 1("
rwnerft8I8lU1t8c8 IF'" .'- \' ::>£,(:1( ~, I: \\ ~,£'-""'.
8OI1n1lll-. 'It ' . ""t, ~ i'~;".{ " Ii; ;,.;-~" :.:
..=-:.:.:/;~ '__nu-' '-. - --u - - --- - --) 'i/" ~->~::=~:=:-.Jk' - -
2.1-- /1/ ir-----------i', ----
"'11'"'11' I ! I 0 W-5 '. -- '-; J \, - - -' " ,
/ .I I (3.4) - ' '-', ',:-- -
II! / I .' .,.', , ,,' ,'-,:~' -
! 111 /,,' 'j> .:"" ..,/ , ;.' /
j~/'~!~-------_. .--:".' (\,/ /":;::>-:.'/
~;l~W ~/.._.,>""":-/ /"/ j/
~{.~..., ~~: ,/ if
1", f :'~'~< .':-:c::':s~:~~~:_.._,.. ,/ --~.-::.~~ 1,,-.:.:.::..:::-
'.. ' -~--- 0 100 200 300 400 SOO feet
...--:;::::;::::::_--- I',
-....- -""--
P-4 Piezometef'soU
o ~Ie location
-
W.1 Well soil
o ~Ie location
(26.4) Menic
concentration
~ mgikg
(NC) Nol c:oIIecI8d
Figure 6-1. ARSENIC DISTRIBUTION IN
SURFACE SOIL L-P PLANT
- 31 -
-------
, I
I
,
-, -, " , I
I ,,-"'---' I" _f ~.~ w.s ", "I '
J 0 ,-- I .
, -. . .: c= =-_..-. (2 .8J"-@ 14 .~.~.5 Itl
. I - ..' .' --:..._~'::'::;'b~L.~(,.9JL@~-29ft)
, I .~ ; C:P~ W 10 ."" I.
W.1 W.. ~ndwa'" I. --- : ,I}- (NAIj '.',. I 'I
M~' :-= i:: U.. L.n}<.-_- c -1_) '1\
.j P.20 ., ." - " ; (..~, ~I' f; ~ L" I
(:o~:- Ii: /-_(~~I;:._..- L~LJ &~~I ~:'ir/' .
::'. II~M~'~qJ~ ~2~~;5f::U u ----------T---- ----------'w'~o\~-j
sawn ~ :'W4 .... J:
inlllVllin"'l: "', " LOUISIANA-PACIFIC (NAill
~coIed8d :' ", PLANT ,
(NAI ~~ ~.<--._' / w~J1
. ,. ~ I '- (NAill
J =1Ion . I:' '-'" ; ,':::;', ~O~ ~ECK ~ ".;S'7' ,-OG D1:CP': ,.
L ReUlIs gr88* '/'/' ; "" ..' 0 ,-4 i\ ,j
.." cuqu8110 : (N A I I:
:.e:= ':/: .i Ii /,~<
connct requred k W. 70 : ::?" . '
qu8t1ila1on 11m i) (NA1:1 ,-:,~~
...: ~.. from . 't' .~ 1= It
:;d::tar I~I -, ,-----\- ~:~,~': .! (\~.
-*:1ID.301IG/l It : . '"., , t,',!-;c " ,: ,\
nd8l8clOnlmll if{ I \ ~ / ; :.", I I..
II"!O'L ! '------" , ''', ,.. \ J'I
. / /17i ; '---__-__h__m"-"S":J ;ML~Oj~~7'~7~~' J /~
i ,/1 r.-- ----_U, i -/"'" I
I" OW-6 - " J \... --, '
1/// tNAI, ,;:-~'~ ,./ -7,:;':\
i:f,1; ---------<:,., -.J." ,/"'/ /:;~/
Iff~.~/..---- '.'. (' /.....,~./
11.f-'/' / ~:-~- /.' ,.,,-,/ \ " 1/
h~ .~ : " ./ ! i
<"/ ,'--:---':', , " .. \ ,/ ) j
Ir' ~,:' '. ----- . ,,'-':. ~"I.i~..P'''.', / v'" "-
... ('('''' ---,,_.~~-~.~-,_:,:: .",~--,'. .-':, .--::-~ 200 300 400 ~-~~~
.----- --~ ~ 1~ I J
--,..~---
~
,,,.
!
-- ----- - - - - ----- --------~
P.10(NA)
"
-----~
EXPlANATION
P-4 Piezometer
o groundwater
~Ie location
Wt:$-~ '~'.
~p..v .I[~:~
Figure 6-2. ARSENIC DISTRIBUTION IN SHALLOW
GROUNDWATER L-P PLANT
,-:::; ,"~".~
-------
: I
~
-N-
j
, ,- -----------1
i'r--------------- - -- .:
I -: -.--, , , ,
i:' p.;O . I
. ,I ,--L~c1 L~- ,,--- - i
I
I
: I
- ,
EXPLANATION
;-.,
. . ,',
_......~ -_.
1,1 ;---_.~ (1;', I !1-r' W~(~~OJ @ 18 f~)
i i. :',: L..-'-: ~ - ----" ~ L I ..~ ',,:, ~(420J @ 38 ft)
'I,' -"--~, '" I'
fi U /--"; '~(NDlC":' I
! I: \ ",: I ~..,-r"---J ~ I
1'1 P.2QF"~~"~":',.1 I ".~"- I ~'I ' I
(12OJ@ 18ft), (ND).' --'; ,:," "": ~Q" ..':".~ ....",: I
~~lralionin 'I I' C..._--,.) L Ju 'O~ND) CU" Iv "-
=.:n::: II,' (""'---_-----._m_---_:---~..,;um~~~~~~.u_." :' ,/
during drilling, I', W~b~\~~~'! 28 ft) : W~\ ujj
(ND) NoldellCted 1/' ['.. '."~' LOUISIANA-PACIFIC (88J@18ft)0r=-..,J
! ,'.I!:' )', PLANT (64J@38ft)'1
J :=~ I :,r.. i. \ i ~':
I ! I:: '~~,~ '< ,/ W.g (
No.:'-' da. fnlm : I" 'I ---', / (ND@29ft):
WCC: 11l8III0111..,.. I I ',- ',~ I (17 J@49ft)'/'
dCllllC8rllIarHCHO i ! II' ",! \ -,,...- -, I
IIS.8IId /. "." " I ,'-IES'""L-:-G::!:::X > EAS,...AJ"'!:CO< ,
d8I8cIIonlrnnil'O jilt I -----' ;\ :
1IOt"..: NOIweruo' I : f '1/; ° P A '~\"" 'I
R::Uded In EA I1Ik , , I I ! - "
I I I, i (ND) '. J.,' ,
c:aIcUI8IIoIW nor ...! : i ! ! Ii
~8ndW.7,AI j I: ,/; .. ' I /':'
__Ir8IIoI..i ; ;1'': I W.7,...-::'
---1nCUI8Ci I liP (420J @) 12 ftlO ,: /7"
/ ! /I[ ./.\ (99J @ 46 ft) 'I /.7:"
! / 1,/,.' i / I: ,(/ :,'
! /f0// ---- -y ..,x \, i r
.: ,i ,',/]f' .,~'" 1,/ 1.' ~:=-C.,K : I; \"\
: : I' ,. '..1'1 ,. ;0:;, ,C' \ .. \
:'f.i/ 1 ~ ~,) . \ ',""
! ! Ii, "-.m" \. j" ! ; '\, Jl;Y
IJI ~l/ ----,'<\.J(", /,,/
~. I, --- '-, . /'
;.tJ//'~----- -- ",:' :' "
/~-;I! . \.. ,/: '(
k// ~+~""",j :.---.. \
I~~//- q" / ,
V #,t.~' 'f...,.,-,'-:-':'~" .--", '.......- .-." " --- . ,-
~' ." """'" ' ~,:' ~:~.~:~~.::,:..,:,~.: ..'
I: !
II ~, : ....--- ..
P-4
o
Piezomeler
groundwater
sarf'4)le Iocalion
W.' Well
o groundwater
~ Iocalion
'to z.~... -£ =",
:::::;';., .. ~.:'
.-.--...!:::-:
- /
, ----
'- ----- .
. ~ - ~ .. .......
". ~ ';",'.""" -
"
" ,
.. ,
~~:;;"
/":~//
, , ,
, /,' (/
,., : '
V'" .J I,. .
-- _.:::::-=:..:.:.:-
200 300 400 500 feet
Figure 6-3. FORMALDEHYDE DISTRIBUTION IN
SHALLOW GROUNDWATER L-P PLANT
-------
emission rates. The potential upper-bound excess lifetime cancer
risk was calculated to be 6 x 10-6 for an annual average gaseous
formaldehyde concentration of 7.8 ~g/M3 at the northern receptor.
Exposure to airborne emissions from the hardboard plant was
fully characterized in the RI, and the risks associated with this
exposure were fully evaluated in the EA. Therefore, no addi-
tional information is necessary to identify these risks.
6.4 Excosure to Surface Soil at the Plant CFU1)
Under future-use scenario FU1 (exposure of a child resident
by contact with plant surface soil) concentrations of arsenic ex-
ceeded the threshold of concern in the average exposure case
(Table 6-2). Arsenic concentrations detected in surface soil
samples from Wells W-6, W-7, and W-9 were not included in the
risk assessment calculation because EPA's Record of Decision
(ROD) for the Koppers site calls for cleanup of soils by Koppers
along the eastern side of the L-P plant where these wells are lo-
cated. All remaining surface soil samples analyzed for arsenic
were above the 1.4 mg/kg residual concentration (that is, the
level associated with a cancer risk of less than or equal to 1 x
10-6) (Tables 6-2 and 6-3, and Figure 6-1) with a maximum con-
centration of 12.6 mg/kg.
Although there is insufficient to establish remedial action
goals for the site, there is no uncertainty that the concentra-
tions of arsenic present in the soil at the site pose a potential
public health risk in excess of the threshold level of concern
. under this future use scenario.
6.5 Inaestion of Groundwater at the Plant CFU4)
In future-use scenario FU4 (exposure of adult resident by
ingestion of shal~ow groundwater from beneath the plant), the
risk of exposure to arsenic was found to exceed the residual con-
centrations for both a cancer risk of 1 x 10-6 for the average
exposure case and 1 x 10-4 for the maximum exposure case (Tables
6-2 and 6-3, Figure 6-2).
The risk assessment was based upon arsenic concentrations in
groundwater sampled from five plant monitoring wells tapping the
shallow aquifer. These wells are W-4, W-8, ML-1, ML-3, and ML-S.
All the other monitoring wells tap the regional aquifer (Table
6-4). Of the five wells, four had arsenic concentrations in
groundwater ranging from 1.9 to 5.6 ~g/L. Well ML-S had a con-
centration of 38 ~g/L, significantly higher than the others.
- 34 -
-------
ML-5 lies approximately 60 feet south of the log deck pond
(Figure 6-2). It is likely that this high level of arsenic is
related to the well's proximity to the log deck pond, where both
surface water. and pond sediments are known to contain arsenic.
The water level in Well ML-5 appears to fluctuate in response to
water level changes in the log deck pond, suggesting that
groundwater in the well and surface water in the pond are in
hydraulic communication. One possible explanation for the higher
arsenic levels in ML-5 is that reducing conditions in the pond
sediment could result in the release of arsenic in its more
mobile reduced ionic state. The arsenic then might move into the
area of Well ML-5 when the log deck pond level is higher than
groundwater levels - that is, when the gradient and flow direc-
tion are from the pond to the well.
Although there is insufficient information to establish
remedial action goals for the site, there is no uncertainty that
the concentrations of arsenic present in the groundwater at the
site pose a potential public health risk in excess of the
threshold level of concern under this future use scenario.
6.6 Inhalation of Volatiles in Groundwater at ~he Plant (FU5)
In future~use scenario FU5 (exposure of adult resident by
inhalation of volatilized organics from shallow groundwater
beneath the plant), the potential risk of exposure to formal-
dehyde was estimated to exceed a cancer risk of 1 x 10-6 for the
average exposure case and 1 x 10 -4 for the maximum exposure case
(Table 6-2, Figure 6-3). The risk assessment was based upon for-
maldehyde concentrations in groundwater samples collected from
shallow depths (less than 50 feet) during drilling. Six of 12
sample locations (Wells W-4, W-5, W-6, W-7, W-8, and W-9) had
formaldehyde concentrations above detection limits during drill-
ing. These samples had formaldehyde concentrations ranging from
17J to 650J ~g/L.
Sample locations W-6, W-7,. and W-9 were excluded from the
risk assessment because EPA's 1989 ROD for the Koppers site re-
quired cleanup of the groundwater along the eastern side of the
L-P plant where these wells are located. Concentrations of for-
mal~ehyde in the three wells used in the risk assessment (W-4,
W-5, and W-8) ranged from 28J to 650J ~g/L.
As discussed above, additional monitoring is necessary to
determine conclusively whether formaldehyde exists in the shallow
- 35 -
-------
groundwater at the L-P plant at the levels detected. However,
formaldehyde is a carcinogen even at levels lower than those
detected. The detected levels of formaldehyde pose a potential
threat to public health from exposure to groundwater at the site
under this future use scenario.
6.7 Inhalation of Volatiles in Groundwater at the Landfill (FU7)
In future-use scenario FU7 (exposure of adult resident by
inhalation of volatilized organics from the regional aquifer at
the landfill), formaldehyde was estimated to exceed a cancer risk
1 x 10-6 for the average exposure case, Table 6-2). The risk as-
sessment was based upon formaldehyde concentrations in three of
four samples of groundwater collected during drilling of Wells
W-2A and W-3B at the landfill. These samples had formaldehyde
concentrations of 143, 27, and 45 ~g/L at depths of 150, 185, and
209 feet, respectively. Formaldehyde was not detected in ad-
jacent Wells. W-2 and W-3 after they were completed and sampled as
monitoring wells.
The presence of formaldehyde in groundwater beneath the
landfill is uncertain because it was not ~etected during monitor-
ing. Therefore, additional monitoring is necessary to con-
clusively establish the presence or absence of formaldehyde in
groundwater bene~th the landfill. However, the informatipn
presented above is sufficient to establish a potential threat to
public health from exposure to the groundwater beneath the L-P
landfill under this future use scenario.
6.8 Environmental Risks
The Remedial Investigation and the Endangerment Assessment
both looked at potential environmental receptors on or near the
site. The Feather River wildlife Refuge is located on the west~
ern side of the Feather River and may be a habitat of certain
threatened or endangered species of wildlife. However, no such
species are known to inhabit the site, primarily due to the dis-
turbed, industr~al -nature of the area. contaminants of concern
were not been detected in Feather River surface water or sedi-
ments in EPA's 1986 sampling done as part of the Koppers RI.
The potential risks to terrestrial and aquatic species of
plants and animals associated with the chemicals of potential
concern at the L-P site were assessed in the EA. The method used
in the assessment of risks to aquatic organisms and plants was to
compare the concentrations of contaminants (in each of the media
such as surface water, soil, and sediment that the species might
- 36 -
-------
encounter) with toxicity reference values (TRVs) for those
species. Risks to terrestrial' animals were assessed by comparing
estimated doses (calculated based on geometric mean and maximum
contaminant concentrations) to TRVs. Where Ambient Water Quality
Criteria (AWQC) have been developed or proposed by EPA, these
were used as TRVs in the assessment of risks to aquatic life.
A summar¥ of the comparison of contaminant concentrations
and estimated doses to TRVs and AWQC is presented in Table 6-5.
The general conclusions regarding the potential for environmental
risks are summarized below.
The potential for toxic effects on aquatic organisms was
present in each of the four locations of surface waters
evaluated: 1) the L-P log deck pond, 2) the off-site ponds south
of the L-P plant, 3). other surface waters at the L-P plant, and
4) the leachate .collection ponds at the landfill. Some of the
chemicals which exceed TRVs or AWQC appear to come from the Kop-
pers facility, and others may be the result of the mineral con-
tent of the soils in this area.
The L-P log deck pond receives run-off from the log deck and
also from the adjacent Koppers Superfund Site. Historically,
run-off from the Koppers site has been significantly contaminated
with chemicals used in the wood treating processes, which include
many of the chemicals listed-in section "A" of Table 6-5. As the
cleanup remedy at Koppers is implemented, water quality in the
log deck pond should improve substantially.
The off-site ponds are downgradient of the log deck pond and
as a result receive run-off from both the L-P site and Koppers,
as well as from other commercial facilities (including a junk
yard) adjacent to the ponds. Available data are not sufficient
to determine which of these may be the source(s) of the chemicals
in these ponds which exceed TRVs or AWQC. .
The other surface water sa~ples taken at the L-P plant were
primarily wet weather samples of run-off and small run-off col-
lection "ponds". The only dry weather samples were from the
ditch along the L-P/Koppers boundary and from the western sump.
Water quality in the ditch will be improved by the soil cleanup
to be conducted in that area as part of the Koppers remedy. The
western sump is essentially a small industrial pond that receives
blowdown from the L-P boilers and run-off from the log deck.
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Table 6-5. Summary of Potential Environmental Effects
A.
Chemicals Detected in Surface Waters at Concentrations
Exceeding TRVsa or AWQCb
RECEPTOR
L-P Log Deck
Pond
Off-Site
Ponds
Other Surface
Waters at the
L-P Plant
Landfill
Ponds
T.rr..~ri.l
ADiaa18
Quail
None
Rabbit
None
Aqu.~ic Lif.
PCP
Aluminum
Boron
chromium(VI)
Copper
Iron
Lead
Manganese
Vanadium
None
None
Aluminum
Boron
. Copper
Iron
Lead
Manganese
Vanadium
Aluminum*
Barium*
Iron*
Mercury *
Aluminum*
Barium*
Chromium*
Iron*
Mercury*
Nickel*
Aluminum
Arsenic
Barium
Beryllium
Boron
cadmium
Chromium(VI)
Chromium(III)
Copper
Iron
Lead
Manganese
Mercury
Nickel
Vanadium
Zinc
None
None
Barium
Boron
Chromium(VI)
Copper
,Iron
Manganese
Vanadium
~V.I Toxicity Reference Values
bAWQC: Ambient Water Quality Criteria
None: No chemical. exceeded TRV8
. : only ~he max~um ~oses exceeded TRVs
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Table 6-5. Summary of Potential Environmental Effects (concluded)
B.
Chemicals Detected in Surface Soils at Concentrations
Exceeding TRVsa
RECEPTOR
L-P Log Deck
Pond
Off-site
Ponds
Other Surface
Waters at the
L-P Plant
Landfill
Ponds
~.rr..trial
Plant.
Antimony
Boron*
Chromium*
Copper
Manganese*
Nickel*
Zinc
Nickel
'rRVs: Toxicity Reference Values
bAWQC: Ambient Water Quality Criteria
- - : Not evaluated for this location
* : Only the maximum doses exceeded TRVs
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Risks to terrestrial wildlife were evaluated by estimating
the effects on two indicator species (rabbits and quail) from
ingestion of surface water at the L-P site. Estimated doses to
quail and rabbits based on geometric'mean concentrations of con-
taminants are below the TRVs for all sampling areas. Maximum
doses to thes~ animals exceeded TRVs for one or more chemicals at
the plant only.
Risks to terrestrial plants were evaluated at the L-P plant
and the landfill. The geometric mean concentrations of the
chemicals of concern ,at the plant are less than the TRVs except
for antimony, copper and zinc~ At the landfill, only the maximum
concentration of nickel in surface soil exceeded the TRV. The
landfill surface soils are primarily soil excavated locally and
placed over the landfill material as a cap. Risks from organic
chemicals were not assessed because of insufficient information
on plant toxicity.
The environmental risks posed by the Site do not warrant any
interim remedial action.
6.9 Risks to be Addressed bvInterim Remedial Action
The potential future residential use of the L-P site poses
risks of human exposure to surface soil at the L-P plant and
groundwater at the plant and the landfill exceed the threshold
level of concern. However, additional information is needed to
resolve uncertainty about the existence of formaldehyde in
groundwater and the background concentrations of arsenic in soil
and groundwater. It is therefore not possible at this time to
set remediation goals or select final remedial actions for the
site. The interim remedial actions selected in this Record of
Decision are necessary to eliminate the potential for exposure to
contaminated soil and groundwater prior to selection of a final
remedy~
7.0
DESCRIPTION OF ALTERNATIVES
Remedial alternatives were not developed for hardboard plant
emissions discussed in Section 6.3 because EPA determined that it
was appropriate to evaluate these emissions under the Clean Air
Act.
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Until data on background concentrations of arsenic in soil
. and groundwater and the presence or absence of formaldehyde in
.groundwater are obtained, the actual risks posed by exposure to
soil and groundwater at the site cannot be fully characterized,
and alternatives for addressing such risks cannot be identified
and evaluated. Alternatives identified and evaluated in the
Feasibility study may be considered in selecting a final remedy
for this site after the necessary additional data is obtained.
For purposes of preventing exposure to contaminated soil and
groundwater at the site, EPA evaluated several interim institu-
tional controls.
To prevent access to contaminated soil at the L-P plant, EPA
considered site access restrictions such as perimeter fencing and
deed restrictions on future residential use of the site. This
alternative is more effective in preventing possible future
residential use than no action, and is implementable. The cost
of this alternative is estimated to be $193,000 based on the cost
of fencing the perimeter of the plant.
To prevent domestic use of shallow groundwater at the L-P
plant and regional groundwater at the L-P landfill, EPA con-
sidered institutional restrictions on the drilling of wells and
extraction of groundwater. This alternative is effective ~n
protecting human health by preventing potential exposure to con-
taminated groundwater. Such restrictions on use are imp1ement-
able through the Butte County well drilling permit program at no
. significant cost. Additional monitoring will be performed to
define the areal extent of contamination, including the construc-
tion of additional offsite monitoring wells if formaldehyde is
detected at the detection limit during monitoring of existing on-
site wells. If additional wells are needed the estimated capital
costs of these wells is $119,000, and the estimated net present
worth cost is $411~000.
variations on these alternatives were evaluated in the
Feasibility Study and presented in the proposed plan as EPA's
preferred alternative to addressing risks posed by the site.
~ discussion under Section 11.0 DOCUMENTATION OF SIGNIFICANT
CHANGES. .
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8.0
APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS (ARARs)
AND TO-BE-CONSIDERED CRITERIA
Remedial actions selected under CERCLA, as amended by the
Superfund Amendments and Reauthorization Act of. 1986 (SARA), must
ensure protection of human health and the environment. SARA
specifies that any selected remedial action must achieve a level
or standard of cleanup that meets legally applicable or relevant
and appropriate requirements, standards, criteria, or limitations
(ARARs).
ARARs are generally separated into three categories: (1)
ambient or chemical-specific requirements that set health- or
risk~based concentration limit~ or. ranges for particular chemi-
cals; (2) performance, design, or action-specific requirements
that govern particular activities; and (3) location-specific re-
quirements. ARARs for the L-P site are discussed in sections 8.1
through 8.3.
The wastes on the site are not hazardous wastes as defined
in the Resource Conservation and Recovery Act (RCRA). None of
the remedial alternatives involves the placement of such wastes
and consequently the RCRA land disposal restrictions (LDRs) are
not triggered.
No formai determination of the presence of wetlands was made
during the RIfFS. The log deck pond and surrounding area would
be potential candidates for such a designation. The institu-
tional controls described in this Record of Decision do not in-
volve the construction of facilities on or management of such
areas, and oth~rwise have no adverse effe~t on such areas.
8.1 Contaminant-SDecific ARARs .
The potential "contaminant-specific.ARARs that apply or are
relevant and appropriate to thE L-P site are presented in Table
8-1. These are subdivided into Safe Drinking Water Act Maximum
Contaminant Levels (MCLs) promulgated by the federal government
and by the State of California, and Ambient Water Quality
Criteria (AWQC) for drinking water and for fresh water aquatic
organisms.
These contaminant-specific ARARs must be considered for any
groundwater remedial actions. There are no contaminant-specific
ARARs for soil at the L-P site.
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POTENTIAL CONTAMINANT-SPECIFIC APPLICABLE
OR RELEVANT AND APPROPRIATE REQUIREMENTS
(ARARS) LOUISIANA-PACIFIC SITE
Table 8-1.
Ambient Water Qualiry Criteria (AWQC)
Safe Drinking (".gIL
Chemical Water Act MCLsa
(~gJt.) Drinking Water Only b =resh Water Aquatic
Organisms Only C
Benzene 5(1)d 0(0.67) -
.
Ethylbenzene (680)d 2.400 -
Isopropyl E!her - - -
Methylene Chloride - - -
Penta.chIorophe4lO1 22Qi 1,010 20.00/13.00 e
T etrachiorophellOl - 1.0 -
PAHs CarcillOgenic - 0(0.0031) -
Nonc:atQnogenic - - -
PCDDslPCDFs - 0(0.00000018) g -
Toluene - 15,000 -
Xyienes ,(1,75O)d - -
Formaldehyde - - -
Atsenic 50 0(0.25) 360.00/190.00 I
Barium 1,000 - -
Boron - 750h -
Chromium 50 50 16.00/11.00 j
17001210 j
Copper 1,000 1,000 18112k
Nickel - 15.4 14001160 k
. Standards are prim8Iy MaxinI.m Conllminant lewis (MCLs),
and are based an N81...,.tId cacl8fdetatianl, and
88Chr IoIogic8I and .ooI....TIic taaibiIity of control, except for
capper. For c::IOA*. the MCL iI an SMCL or Secondary
Max8nuTt Concanw.nt l.e¥8I baed on organa'eptic effects
b Adju888d EPA Ambient Wal8r Cuaity Criteria (Awacs) tor
drinking walllr onIr. Awacs tor pc8IIntial C8IcillOgeI. are
"'8t zeto; vaIue8 in poren1heles are conc:enlralions
associated with 10-' exceu lifedme cancer risk. Criterion la
capper iI based an organoleptic cansidefalions
c Two values are given (e.g. 20.00113.00) 20.00 . 8c:ut8 value a
1 hour eKPC*'l'e per 3 years; 13.00. c:hronic value or 4 days
eKPC*'1'8 per 3 ~
d Paren1he1ical value iI . Califomia slate maximum oontaminant
IeYeI
- 43 -
e V~ are pH-depetldent; based on pH 01 7.8
f Values for Ar.nic (+3)
g For 2. 3, 7, .. TCDD. Dioxinlfuran toxicity 8quivaAenls are also
UI8d in da"'",;.,;,1g 2, 3, 7, 8 TCDD levels
h Boron AWOC . baed on profedion of sensitive crops during
q.18tm irrigation
i EPA proposed maximum contaminant level goal
j Values for boch Chromium (+6) on upper line. and c:hromium (+3)
on lower line; Cr(+3) is hardness dependei"lt (100 mgll used)
k Values for Copper and Nickel are hardness-dependent; based on
hardness of 100 mgtl. 01 CaCC>.J
-------
8.1.1 Federal Drinkina Water Standards. Potential drinking
water standards at the L-P site include Maximum Contaminant
Levels (MCLs), Maximum Contaminant Level Goals (MCLGs), and
Secondary Maximum Contaminant Levels (SMCLs). As stated in
CERCLA Sectio~ 121(d) (1)" MCLGs are potential cleanup standards
when these levels "are relevant and appropriate under the cir-
cumstances" and are not a zero value. In general, the relevant
and appropriate standards to establish groundwater cleanup levels
at the site are the Federal Maximum contaminant Levels (MCLs) es-
tablished under the Safe Drinking Water Act (Table 8-1, Column
2) .
There is no MCL for formaldehyde. The MCL for arsenic is 50
ppb, which is not exceeded at this site. Therefore the selected
interim remedial action will comply with the ARAR for'
groundwater.
8.1.2 State Drinkina Water Standards. California Drinking Water
Standards establish enforceable limits for substances that may
affect health or aesthetic qualities of water and apply to water
delivered to customers. The state's Primary Standards are based
on federal National Interim Primary Drinking Water Regulations.
Currently, for contaminants found at this site, or known to be
present on the adjacent Koppers site, California has promulgated
MCLs for benzene, ethylbenzene, and xylenes (values in paren-
theses in Column 2 of Table 8-1).
8.1.3 Ambient Water Oualitv criteria. Adjusted EPA Ambient
, Water Quality Criteria (AWQCs) for drinking water are potential
ARARs for the L-P site (Table 8-1, Column 3). For potential car-
cinogens, AWQCs are set at zero. For certain contaminants, con-
centrations associated with a 10-6 excess lifetime cancer risk
are also shown (values in parentheses) in Column 3 of Table 8-1.
8.2
Action-SDecific ARARs '
The interim remedial actions described in this Record of
Decision do not trigger any action-specific ARARs.
8.3 Location-SDecific ARARs
8.3.1 Fault Zone. The L-P
(200 feet) of an identified
quirement of 40 CFR Section
site is not located within 61 meters
fault. Therefore, the fault zone re-
264.18(a) is satisfied.
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8.3.2 Floodplain. Under 40 CFR Section 264.18(b), hazardous
waste treatment facility located in a 100-year floodplain must be
designed, constructed, operated, and maintained to prevent
washout of any hazardous waste by a 100-year flood, unless one of
the exemptions listed in the regulation applies. The L-P site is
located in a 100-year floodplain of the Feather River. The in-
terim remedial actions described in this Record of Decision do
not include treatment, and therefore the requirements of 40 CFR
Section 264.18(b) are not triggered.
8.4 To-Be-Considered Criteria
In establishing remedial alternatives, EPA considers various
procedures, criteria, advisories, and resolutions. These "to-
be-considered" criteria (TBCs) do not carry the weight of ARARs,
but may be relevant to the cleanup of a site. The only such
criterion relevant to the interim remedial actions described in
this Record of Decision is the California Department of Health
Services' Recommended Drinking Water Action Level for formal-
dehyde, which is 30 ppb.
9.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The interim actions described in this Record of Decision
represent a cost-effective means of preventing potential exposure
to contaminated soil and groundwater at the site. Because these
institutional controls do not represent the final remedial ac-
tions at the site, they have not been compared to other remedial
actions which may be selected in a final Record of Decision.
These measures have, however, been evaluated against EPA's nine
evaluation criteria:
1) Overall protection of human health and the environment
The institutional controls prevent contact with
contaminated surface soil and groundwater, thereby
limiting human- exposure and reducing potential future
risks below the level of concern.
2) Compliance with ARARs
There are no ARARs, criteria or guidance that apply
to arsenic in surface soil. The MCL for arsenic in
groundwater, 50 ppb, is not exceeded at this site.
There are no ARARs for formaldehyde in groundwater. The
California Recommended Drinking Water Action Level, a
TBC criteria for establishing remedial action goals at
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Superfund sites, for formaldehyde is 30 ppb. The in-
terim institutional controls will not meet this stan-
dard.
Short-term effectiveness in orotectina human health
and ~he environment
The risks associated with soil and groundwater con-
tamination at this site are future risks. The interim
institutional controls reduce these risks below the
level of concern, and implementation of these controls
will not create any short-term risks.
3)
Lona-termeffectiveness and Dermanence in Drotectina
human health and the environment
The institutional controls are effective as long as
they are enforced by EPA.or local authorities. Because
this is an interim remedial action, these measures are
not intended to be permanent, but only to prevent ex-
posure during selection of final remedial measures.
4)
Reduction of toxicity. mobility. or volume of
contaminants by treatment
The institutional controls do not meet the
statutory preference for treatment to reduce toxicity,
mobility, or. volume of contaminants. Once the risks
from exposure to site-related contaminants has been
finally characterized, the need to treat these con-
taminants can be assessed.
5)
Technical and administrative feasibility of
imDlementation
The institutional controls can be readily imple-
mented. The deed and well use restrictions can be ob-
tained through. Butte County. site access restrictions
can be implemented by Loui~iana Pacific.
6)
CaDital. operation. and maintenance costs
The capital cost associated with implementing site
access restrictions is estimated to be $193,000, based
on the cost of fencing the perimeter of the site. No
significant long-term operation and maintenance costs
are associated with this action. The deed and well use
restrictions can be implemented at no significant cost.
If additional offsite monitoring wells are required to
determine the presence or absence of formaldehyde in
7)
- 46 -
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groundwater, the estimated capital cost of such wells is
$119,000, and the estimated net present worth cost is
$411,000.
8) ~ Community acceptance
Except for a letter from a member of the Oroville
City Council expressing the opinion that the site should
be deleted from the National Priorities List, all com-
munity concerns were expressed during a public meeting
on the proposed plan. Community members raised the fol-
lowing major concerns:
- all site contamination should be cleaned up,
rather than using institutional controls that
allow contaminants to be left in place;
- something should be done about plant air
emissions;
- institutional controls should not create a
permanent industrial zoning for the site; and
- since the levels of contamination are so low,
the process to remove the site from the NPL
should begin as soon as possible.
Responses to all comments are set forth in the
Response Summary which accompanies this Record of Decision,
9) State Acceptance
The State of California supports the interim
remedial actions proposed by EPA. In its comments on
the proposed plan, the State Department of Health Serv-
ices provided several suggestions for implementing the
selected remedy during RD/RA. These concerns will be
taken into consideration during implementation.
10.0 SELECTED REMEDY
10.1 Selected Soil Remedy
EPA has determined that additional information is needed to
determine background levels of arsenic in soil and to set
remedial action goals for the site. During the time that addi-
tional information is collected and analyzed, however, the poten-
tial risk of exposure to contaminated surface soil at the site
remains. Therefore, to eliminate the potential for exposure to
contaminants from the site, EPA has selected to employ institu-
- 47 -
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tional actions as an interim remedial action.
actions consist of:
Such institutional
o
Deed restriction on future residential use of the
L-P plant
Site access restrictions, e.g., fencing the
. perimeter of the L-P..
o
The total capital and present-worth costs of the institu-
tional actions are estimated to be $193,000.
The deed restrictions are necessary to prevent future
residential use. of the site. Despite current zoning restrictions
and the presence of the L-P facility at the site, residential
development may occur at the. site. Zoning restrictions are not
permanent, and L-P could sell the property to residential
developers. The site is near other residential property and is
otherwise suited for residential use. Substantial time may be
required to collect and analyze the additional information neces-
sary to make a final remedial determination at this site. The
deed restrictions are therefore appropriate interim measures.
The site access restrictions are necessary to prevent cur-
rent access to the site by trespassers, particularly children who
live near the site. L-P has acknowledged that incidents of
trespassing have occurred at the site. The levels of arsenic in
the soil pose a potentially unacceptable risk to such
trespassers. .
Additional sampling will be conducted to determine back-
ground concentrations of arsenic in surface soil on and near the
L-P plant.
10.2
Selected Groundwater Remedv
EPA has determined that adaitional information is needed to
obtain additional information about the presence of formaldehyde,
to obtain information about background levels of arsenic in
groundwater, and to set remedial action goals for the site.
During the time that additional information is gathered and
analyzed, however, the potential risk of exposure to contaminated
groundwater remains. Therefore, to eliminate the potential for
exposure to contaminants, EPA has selected to employ institu-
tional actions at the site. Such institutional actions consist
of:
- 48 -
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o
Well permit restrictions to (1) prohibit the drilling
of shallow aquifer wells on or near the L-P plant, (2)
provide proper seals on deep wells on or near the L-P
plant which are drilled through the shallow aquifer,
and (3) prohibit drilling of deep wells at the L-P
.lan4fil1.
The institutional controls for groundwater ~valuated in the
Feasibility ~tudy and described in the proposed plan as part of
the proposed final remedy included installation of five offsite
groundwater monitoring wells to determine the areal extent of
contamination. However, for purposes of this interim remedial
action, EPA has determined. that additional monitoring at existing
wells may be sufficient to determine the presence or absence of
formaldehyde in the shallow aquifer. Therefore the selected
remedy does not require construction of additional off-site
monitoring wells unless formaldehyde is detected above the detec-
tion limit during monitoring at existing on-site wells. The well
permit restrictions can be implemented without significant cost.
The well permit-restrictions are necessary to prevent domes-
tic use of the shallow groundwater associated with the L-P plant
and the regional aquifer beneath the landfill. Such domestic use
could take place despite deed and site access restrictions, since
these aquifers may extend beyond the boundaries of the L-P
property.
11.0
DOCUMENTATION OF SIGNIFICANT CHANGES
The proposed plan for the L-P site was released for public
comment in May, 1990. EPA's preferred alternatives and remedial
objectives were documented in the plan. At that time, EPA
proposed that the institutional controls described above repre-
sent the final remedial action at the site, with ongoing monitor-
ing to assess the effectiveness of and continued need for these
controls. EPA has reviewed all written and verbal comments
received during the public comment period. Several commenters
favored complete cleanup of the site, and some were concerned
that imposing deed and well use restrictions would permanently
inhibit flexible development of the L-P property. Other com-
menters felt that, because the information on background levels
of arsenic, and the existence of formaldehyde is inconclusive, no
remedial action should be taken at all.
- 49 -
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The selection of interim institutional controls will prevent
exposure to contaminated soil and groundwater while additional
information is obtained which will allow EPA to establish what
remedial goals, if any, are appropriate for this site. The
change from a final to an interim remedy does not fundamentally
alter the scope, performance, or cost of the selected remedial
actions.
The institutional controls for groundwater evaluated in the
Feasibility study and described in the proposed plan as part of
the proposed final remedy included installation of five offsite
groundwater monitoring wells to de~ermine the areal extent of
contamination. However, for purposes of this interim remedial
action, EPA has determined that additional monitoring at existing
wells may be sufficient to determine the presence or absence of
formaldehyde in the shallow aquifer. Therefore the selected
remedy does not require construction of additional off-site
monitoring wells unless formaldehyde is detected above the detec-
tion limit during monitoring at existing on-site wells.
12.0
STATUTORY DETERMINATIONS
The selected remedies are protective of human health and the
environment as required by Section 121 of CERCLA. Potential
risks from exposure to contaminated surface soil and groundwater
. are prevented by institutional actions that prohibit residential
development of the site and restrict the drilling of groundwater
wells. The selected remedies comply with ARARs and relevant
TBCs.
The selected remedies are the most cost-effective approaches
available to protect human health and the environment. The
selected remedies u.e institutional actions to eliminate the
potential for direct human exposure to surface soil and
groundwater. These are the only contaminant pathways of concern.
The five-year review required by section 121 of CE~CLA is
applicable to the selected remedies. Additional monitoring will
be performed to establish the presence or absence of formaldehyde
in groundwater and to establish background levels of arsenic in
80il and groundwater.
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RESPONSE SUMMARY
LOU~SIANA-PACIFIC CORPORATION SUPERFUND SITE
OROVILLE, CALIFORNIA
Environmental Protection Agency
Region 9
San Francisco, California
September 1990
-------
Respons. to Public Comments
on the
Proposed Plan and ~easibility study
for the
Louisiana-Pacific Corporation superfund
. Oroville, California
Site
I.
INTRODUCTION
The United states Environmental Protection Agency (nEPA")
held a public comment period from May 14 through June 13, 1990 on
EPA's Feasibility study ("IFS") and.Proposed Plan for the
Louisiana-Pacific ("L-P") Superfund Site in Oroville, California.
The purpose of the public comment period was to provide inter-
ested parties with an opportunity to comment on the FS and
Proposed Plan. The FS and Proposed Plan were made available on
May 14, 1990 at the Butte County Health Department Library in
Oroville and at the Meriam Library, California State University
at Chico. By May 14, 1990, fact sheets containing EPA's Proposed
Plan had been mailed to all interested parties. Notification of
the public comment period was published in oroville, Chico and
Sacramento area newspapers.
A public meeting was held on May 22, 1990 at the Palermo
School in Palermo, California. At this meeting, EPA representa-
tives described the alternatives'evaluated, presented EPA's
preferred alternative and answered questions about the evaluation
of the L-P site and the remedial alternatives under considera-
tion.
Section 113(k) (2) (B) (iv) of the Comprehensive Environmental
Response, Compensation and Liability Act ("CERCLA") requires that
EPA respond to significant comments on EPA's Proposed Plan. This
Response Summary provides a review and summary of significant
comments on the FS and the Proposed Plan. In addition to sum-
marizing significant concerns and questions, the Response Summary
presents EPA's responses to those concerns.
II.
OVERVIEW OF THE RECORD OF DECISION
During the process of developing a proposed plan for soil
and ground water contamination, EPA evaluated several alterna-
tives. EPA's preferred alternatives are described below.
Ground Water Alternative - Institutional Action
, EPA's selected remedial actions for ground water call for
well permit restrictions while additional ground water monitoring
is conducted. Within five years, EPA will conduct a review of
the entire site to determine if any additional response actions
are necessary. .
The proposed well permit restrictions will prohibit future
- 1 -
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on-site and off-site use of both shallow ground water on or near
the L-P plant and deep ground water at the landfill, thereby
preventing exposure from domestic use of such water. . If future
monitoring shows that arsenic and/or formaldehyde, either singly
or in combination, are present at levels that trigger the need
for additional remedial actions, then EPA will evaluate possible
responses.
soil Alternative - In8titutional Action
The public health risk from contaminated soil is a future
risk associated with residential use of the L-Pplant site. Such
development is currently prohibited by the Butte County zoning
ordinance which allows only industrial use of the site. EPA has
selected remedial actions that would result in restrictions to
site access (for example, fencing) and, via the property deed, a
more reliable prohibition against future residential use of the
plant site.
The selection of these remedial actions for soils is based
on existing data about arsenic contamination at the site. If, in
the future, additional data about background levels of arsenic in
soils at the site show that the concentrations at the plant do
not exceed background, then the remedy will be revised.
III.
SUMMARY OF COMMENTS AND AGENCY RESPONSES
Both written and verbal comments were received by the En-
vironmental Protection Agency (EPA) during the public comment
period of May 14 - June 13, 1990. These comments and the EPA
responses are presented in this section of the Response Summary.
These comments, which include statements, questions and concerns,
-are grouped into the following subject categories:
A.
B.
C.
D.
E.
F.
G.
H.
I.
J.
General Community Concerns
Deed'Restrictions
Well Permit Restrictions
Fencing
Air Emissions
Arsenic in Soil
Formaldehyde in Groundwater
Endangerment Assessment'
Ground water Monitoring
Sources of Contamination
:-
The originators of comments are identified in parentheses by last
name, company or agency abbreviations. Written comments were
received from the following individuals and agencies:
o Louisiana-Pacific Corporation (L-P)
o'Beazer East, Inc. (formerly Koppers Company Inc.)
o Jim P. Carpenter, Director of Parks & Trees,
City of Oroville '
o State of California Department of Health Services ("DHS")
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Verbal comments were received from four individuals and
transcribed during the public meeting held May 22, 1990 in
Palermo, California. Those comments that were documented in the
meeting transcript (available in the Administrative Record) and
not answered during the meeting are responded to herein. They
were received from the following individuals:
- Ron-Harmon
- Donna Ielati
- Ms. Bluford
- Deborah Daugherty.
. After the close of the public comment period, additional in-
formation was submitted by Louisiana-Pacific Corporation in sup-
port of their written comments. This information did not sub-
stantially change EPA's responses to their initial comments. A
copy of their submittal has been placed in the Administrative
Record. .
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A.
General community Concerns
A.1) Every effort must be made towards removing L-P from the su-
. per fund list. The process to remove this site from the list
should be initiated. (Carpenter) .
RESPONSE: Because of the potential health risks associated
with future use scenarios, EPA is proposing limited controls
. and monitoring and therefore will not seek to delist the
site now. Pursuant to CERCLA section 121(c), EPA will,
within five years, review the data collected through the
proposed monitoring program and re-evaluate soil and ground
water conditions at the site to determine if continuation of
the institutional controls is necessary and/or if any other
response actions are needed. If no further response actions
are required, EPA will initiate the process to delete the
site from the National Priorities List ("NPL"). This
process (described in Section 300.425(e) of the National
Contingency Plan, 55 FR 8845, March 8, 1990) includes con-
sultation with the state and an opportunity for public
review and comment on the delisting proposal. .
A.2) I support total clean-up of the L-P site. (Daugherty)
RESPONSE: EPA believes that the proposed remedy is protec-
tive of public health and the environment. The proposed
institutional actions are an effective means of managing the
relatively low levels of contamination and associated public
health risk present at this site. The remedies were
selected for this site using the nine criteria described in
the Proposed Plan, including the two threshold criteria 1)
protection of human health and the environment and 2) com-
pliance.with,applicable or relevant and appropriate require-
ments ("ARARs"). The only contaminant-specific, relevant
and appropriate requirement for chemicals of concern at this
site is the Safe Drinking Water Act's Maximum Contaminant
Level ("MCL") for arsenic in drinking water. The MCL is not
exceeded by existing arsenic concentrations in shallow
ground water at the plant.
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B.
Deed RestrictioDs
B.l) My concern is that we have created a permanent industrial
zoning by putting a deed restriction on L-P's property so
that itqan be used for no other purpose. (Harmon)
RESPONSE: The proposed deed restriction would prohibit only
residential use of the site and would not restrict future
use of the site for other purposes such as commercial or
retail activities. Additionally, the restriction is not
necessarily permanent. For example, if L-P elected to
remove all arsenic in soils to levels that would be protec-
tive of human health and the environment (assuming those
levels exceed background), EPA would remove the deed
restriction.
B.2) A deed restriction at the site
will permanently impair future
a knowledge of risk assessment
ture. (L-P)
is inappropriate because it
uses of the property based on
that may change in the fu-
RESPONSE: The deed restriction is proposed based on exist-
ing knowledge of contamination at the site and the risk it
poses to human health and the environment. Additional in-
formation is necessary to characterize fully the risk posed
by the site. EPA will obtain and evaluate the necessary in-
formation before making a final remedial determination at
the site.
c.
..11 Permit RestrictioDS
C.l) Well. permit restrictions are unnecessary because California
law prohibits the construction of domestic wells near in-
dustrial ponds or solid waste disposal sites. (L-P)
RESPONSE: The language in the California regulations is
general in nature when it comes to defining "near", and the
enforcing agency is left with substantial discretion to make
that determination. The use of well permit restrictions
over a defined geographical area will allow EPA to ensure
that exposure-to contamination in the shallow aquifer does
not occur.
C.2) The shallow aquifer will require several additional monitor-
ing wells off-property to more accurately determine its ex-
tent before placing well permit restrictions. (CHS)
RESPONSE: The RI did not involve any off-property wells
screened in the shallow aquifer, and thus the extent of this
aquifer is not known. EPA will require additional off-
property monitoring wells as part of the continued ground
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D.
water monitoring.
..ncinq
D.l) Fencing at the L-P site is not justified under CERCLA. The
Endangerment Assessment ("EA") did not find any significant
health risk which could be abated or reduced by fencing the
site. The only use scenario which was found to pose a sig-
nificant !uture risk was future residential development of
the site. Although there have been reported incidents of
trespassing and the current industrial uses may justify
fencing of the site for safety reasons, these factors are
outside the province of CERCLA. (L-P)
RESPONSE: Potential exposure of children to surface soil in
a future residential use of the site was considered in the
EA to be a significant health risk. Children currently
living in nearby residential areas could gain access and
face a similar health risk if the site remains unsecured.
To prevent this potential exposure, the proposed plan calls
for preventing unauthorized access to the site by, for ex-
ample, fencing.
B.
Air Baissions
E.l) What is going to be done about the pollution that's coming
over in the air from L-P? (Ielati, Bluford) .
RESPONSE: During EPA's Remedial Investigation (RI), data
were collected on airborne dust and particulates as well as
formaldehyde emissions from the hardboard plant. These data
have recently been reviewed by EPA's Air and Toxics Division
("ATD") which concluded that at this time there are no
federal, state or local air regulations which require fur-
ther air emission controls at this site. .
Primary responsibility for regulating air emissions
from L-P and other industries in the Orovi1le area rests
with the Butte County Air Pollution Control District
("BCAPCO"). currently, L-P has several permits from the
District that regulate-emissions from the sawmill, planing
-mill, boilers ~nd hardboard plant. These permits contain:
(a)
specific numerical limits on stack gases such as
carbon monoxide (CO), hydrocarbons, nitrogen
oxides (NOx), sulfur oxides (SOx), and particu-
lates; - .
numerical limits ~n particulate emissions from
cyclones and baghouses, including separate limits
on the fiberdryer cyclones at the hardboard plant;
opacity limits;
a requirement that fugitive dust emissions (from
rooftops, sawdust piles, roadways, plant grounds,
etc.) not create a public nuisance outside the
(b)
(c)
(d)
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(e)
(f)
plant boundaries, including requirements for
regular cleaning to control fugitive dust and a
4-hour time limit to clean up after upsets;
requirements for the use of certain air pollution
control equipment on the boilers;
source testing requirements, ranging from annual
testing of the newest boiler to testing every
other year on the fiberboard plant; and
a requirement for continuous monitoring of boiler
emissions.
-(g) .
BCAPCD staff review the monitoring and stack test data
provided by L-P and, as resources permit, they inspect L-P's
operations to evaluate permit compliance. In the past, L-P
has been cited and fined by BCAPCD for several permit viola-
tions. .
E.2) We support EPA's decision that air emissions from ongoing
plant operations should be regulated exclusively under the
Clean Air Act and Butte County Air Pollution Control Dis-
trict authorities. (Beazer) .
RESPONSE: The proposed plan does not state a general policy
that air emissions from ongoing process operations should be
regulated exclu~ively under the Clean Air Act. However, in
this case EPA has determined that the hardboard plant emis-
sions should be regulated under the Clean Air Act.
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P.
Ar..nic in 80i1
F.1) The arsenic soil data from the L-P Remedial Investigation
("RI"),. ~ither standing alone or combined with the back-
ground arsenic data from the Koppers RI, indicate that ar-
senic concentrations in soil at the L-P site are within
background levels. Statistical analysis of the geometric
distribut~ons of the various groupings of the data indicate
no significant differences between the background concentra-
tions and the plant site. (L-P)
RESPONSE: Neither the RI for L-P nor the one for Koppers
gathered sufficient. data to determine actual background ar-
senic levels for these two sites. In fact, as stated in the
Koppers Record of Decision, additional sampling will be con-
ducted as part of the remedial design in order to establish
background levels of arsenic in soils at the Koppers site.
As part of their comments on this issue, L-P used a standard
statistical test knoWn as a lit-test" to compare the
geometric means of a number of different groups of soils
data with "background soii concentrations" from the L-P and
Koppers sites. They concluded that there was no statisti-
cally significant difference in the L-P plant and background
soil concentrations. .
Due to the small number of background samples taken at the
L-P site (3 samples from one boring), it is not appropriate
to perform a statistical analysis on these data. In
general, as the number of background samples decreases, the
probability of a Type II statistical error (i.e., a false
negative) increases. A Type II error would be to make the
conclusion that the means of the plant and background soils
are not significantly different, when they are in fact dif-
ferent (see page 4-9 of EPA's Risk Assessment Guidance for
Superfund, Volume I - Human Health Evaluation Manual, Decem-
ber 1989).
F.2) In their 1984 paper on the concentrations of elements in
sUrface soils, Shacklette and Boerngen do not state that the
regional background concentration of arsenic in the Northern
Sacramento Valley ranges from 4.1. to 16 mg/kg as is
reported in the EA and Feasibility Study (FS). (L-P)
RESPONSE: The regional background range of 4.1 to 16 mg/kg
was inferred from data presented in the report by Shacklette
and Boerngen. In that report, the authors show (on a map)
ranges of arsenic concentrations found within surficial
material in the western u.S. The range stated in the FS is
based on three sample locations on the map nearest to
Oroville. In the actual data tables used in preparing the
map, the two arsenic levels reported for sample locations in
Butte County are ~.8 and 4.5 mg/kg (see Table 1 in USGS Open
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File Report #81-197). In any case, as L-P notes, Shacklette
and Boerngen caution against the use of the document to
determine site-specific background concentrations.
F.3) The FS states (p. 2-21) that higher arsenic concentrations
appear in areas that have received irrigation water from the
. log deck pond and from surface water run-off from Koppers.
The soil ~ata do not support this conclusion. There is sub-
stantial horizontal and vertical variation of arsenic con-
centrations which appears to be independent of plant loca-
tion. (L-P)
RESPONSE: The FS statement quoted in the comment is based
on arsenic concentrations in 12 samples of surface soil.
Five of the twelve sample points (P-1, P-2, W-1, W-5 and W-8
on Figure 2.2-1 of the FS) are located away from areas
receiving sprinkler irrigation and run-off from Koppers; ar-
senic concentrations at these points range from less than
2.2 to 3.8 mg/kg. Surface soil samples collected on the
fringe of these areas (P-3 and W-4) had arsenic concentra-
tions of 4.2 and 9.8J mg/kg. Surface soil samples collected
from within the areas of run-off from Koppers and sprinkler
irrigation (P-4, TP-1, W-6, W-7 and W-9) had arsenic con-
centrations ranging from 3.2 to 26.4 mg/kg. The three
highest arsenic ,concentrations (W-7, P-4, and W-9) were
10"8, 12.6J. and 25.4 mg/kg, respectively. These arsenic
concentrations support the statement in the FS:
"It appears that the location of higher arsenic
concentrations at the L-P plant are in the log deck
areas that have received either sprinkler irrigation
of water pumped from the log deck pond or surface run-
off from the Koppers site."
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G.
Foraaldehyde in Groundwater
G.l) only 10 of the 29 samples taken during the well drilling
measured .positive for formaldehyde, and most of these
samples have significant quality control problems. The fact
that the subsequent ground water monitoring samples did not
have these problems and that all of the 34 samples measured
negative for formaldehyde is sufficient to determine that
there is n~ formaldehyde in ground water at the L-P site.
(L-P) .
RESPONSE: Because of the limited amount of data available,
the issue of whether or not formaldehyde is present in
ground water can not be resolved at this time. The suggest-
ion by L-P that the sampling protocol for samples collected
during drilling of monitoring wells may have resulted in
false positives is one reason to question the presence of
formaldehyde. On the other hand, the results from L-P's own
investigation of ground water quality suggest that formal-
dehyde may, in fact, be present in ground water. Additional
ground water monitoring samples will be collected and
analyzed for formaldehyde.
G.2) Since formaldehyde is highly degradable in the environment,
it is essentially self-treating and therefore no remedial
action is necessary to eliminate its presence in ground
water. (L-P)
RESPONSE: Formaldehyde is indeed a reactive organic com-
pound in nature. In many situations its natural degradation
rate will be appreciable and sufficient to reduce its con-
centration to very low levels in a relatively short period
of time. However, in some. situations, such as under
anaerobic (i.e., oxygen-deficient) conditions in soil, it
can be more persistent. Anaerobic conditions may exist in
portions of the shallow ground water based on organic odors
observed while drilling some of the wells and piezometers
completed during the remedial investigation (e.g., W-6, W-7,
P-1, and P-2). The limited and conflicting data available
on formaldehyd~ concentrations in ground water are not suf-
ficient to determine whether it is .present or the rate at
which formaldehyde may be aegrading. As such, it would be
premature to conclude that remedial action is unnecessary if
formaldehyde is present.
G.3) In the detailed analysis of alternatives, the FS should note
that natural degradation should eliminate any formaldehyde
that is present in ground water. It should also note that
the proposed Maximum contaminant Level Goal ("MCLG") for ar-
senic is 50 parts per billion (ppb). (L-P)
RESPONSE:
While it is true that formaldehyde will generally
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degrade naturally, there are no site-specific data on which
to base an estimate of how long this would take at the L-P
site.. Additional monitoring should provide information on
whether formaldehyde is present and how quickly it may
degrade. .
In 1985, EPA proposed a Recommended Maximum Contaminant
Level ("RMCL") for arsenic of 0.05 mg/L (50 ppb), the same
as the existing Maximum Contaminant Level ("MCL"). See 50 .
Fed. Reg. 46960 (Nov. 13, 1985). The RMCL was never final-
ized. EPA is gathering and evaluating data which may lead
the Agency to propose a new MCL and and new MCLG for arsenic
in the future. .
B.
Bndanq.raent A......ent (BA)
H.1) The EA should have discussed the sensitivity of the risk es-
timates to the use of qualified data. The EA and FS should
point out that much of the data which resulted in findings
of potential significant risk come from data groups that are
among the highest in terms of perceritage of qualified data.
(L-P)
. RESPONSE: Of the chemicals of potential concern identified
in the EA, arse~ic in surface soil and formaldehyde in
ground water represented the majority of the risk. L-P has
compiled data to show that 24% of the arsenic soil analyses
used to calculate a geometric mean concentration for the L-P
plant soils had J flags. assigned by EPA. According to L-P,
76% of the formaldehyde analyses were assigned J qualifiers.
As described in the EPA data validation packages, the J
flags for arsenic data were assigned because instrument
calibration and/or spike recovery were outside of the ac-
ceptable range. The maximum arsenic value (23 mg/kg) was
not assigned a qualifier. Thus, although use of these
J-flagged values may have increased the uncertainty in the
risk assessment, a large impact on the final risk analysis
was not expected. There is no indication of a consistent
bias in the data that would indicate over- or under-
estimation of concentrations.
Data validation qualifiers for formaldehyde were assigned
because formaldehyde was detected in the travel blank and in
the DNPH reagent blank for the analYtical method. EPA data
validation staff corrected the method detection limit for
the samples accompanying these blanks to ten times the
amount detected in the blanks. This adjustment should
eliminate the potential for a positive bias in concentration
due to blank contamination. Nevertheless, a lower degree of
confidence should be placed in these analyses.
EPA believes that the discussion of the uncertainty as-
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sociated with the analytical data presented in Section 5 of
the EA was adequate according to EPA guidance at the time
the report was prepared (i.e., prior to the issuance of the
revised guidance in 1990). The selected remedy for the L-P
site requires additional sampling for formaldehyde in ground
water due to the high uncertainty associated with these
data.
H.2) The EA did not evaluate the excess risk of cancer presented
by arsenic in the L-P plant soils based on the difference
between the mean plant concentration and the mean background
concentration. Rather, it calculated the risk based on the
mean plant concentrations only. (L-P)
RESPONSE: According to EPA guidance at the time the EA was
prepared, distinguishing between site-related and background
contributions to risk was considered a risk management task
to be addressed in selecting remedial alternatives for the
site. The purpose of the EA is to evaluate the risk posed
by existing levels of contaminants and to present data about
background levels of those contaminants without trying to
separate the risks associated with each.
H.3) The shallow ground water is not a realistic pathway for fu-
ture exposures. (L-P)
RESPONSE: During investigation of the L-P site, the shallow
aquifer was found in places to be sufficiently permeable to
yield a significant water supply to shallow wells, if they
were to be drilled. The permeable portion of the aquifer
was found to extend to depths of 50 feet below land surface.
Since shallow wells are less expensive than deep wells,
there might also be an economic incentive to tap the shallow
aquifer for a domestic water supply. .
CUrrent water well standards, published by the California
Department of Water Resources ("DWR") in 1990, specify a
minimum 20 feet depth for the annular seal for individual
domestic wells. Furthermore, the well standards allow the
minimum seal depth to be reduced to as little as 10 feet at
well sites. where the water to be pumped is at a depth less
than 20 feet, as it is at the L-P plant. Butte County now
relies on the DWR standards for permitting wells. There-
fore, without special provisions to the contrary, the
present standards would allow domestic wells to be drilled
which could draw ground water from the shallow aquifer for
domestic use. Thus, a realistic pathway in shallow ground
water does exist, and special provisions like a permit
restriction are needed to prevent the drilling of shallow
wells for domestic use on or near the L-P plant.
L-P infers that the FS describes the shallow aquifer as
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non-potable. The statement in theFS that "shallow ground
water is typically non-potable" was intended only as a
remark about shallow ground waters in general and not a
claim that this specific shallow aquifer is non-potable.
H.:4) The formaldehyde sampling data appears to have been im-
properly evaluated in the chemical characterization portion
of the Endangerment Assessment ("EA"). (L-P)
"RESPONSE: As noted earlier (see response to comment G.1),
the uncertainty in the formaldehyde data was recognized in
the EA and considered in selection of the remedy.
H.5) Because of the non-volatility of formaldehyde, the approach
taken in the EA essentially assumes that an average exposure
consists of inhaling 2.0 liters of water from the shallow
ground water while showering. (L-P) "
RESPONSE: The exposure scenario in the EA assumed that in-
halation of formaldehyde during showering corresponds to the
dose received from ingestion (not inhalation) of 2
liters/day of water. This approach was based on EPA Region
IX guidance concerning exposure to volatile organics while
showering (Risk Assessment Guidance for Superfund Human
Health Risk Assessment, U.S. EPA Region IX.Recommendations
(Interim Final), December 1989, p. 9). The discussion by
L-P of the volatility of formaldehyde is essentially cor-
rect, except that it should be noted that formaldehyde in
aqueous solution exists in an equilibrium between the
methylene glycol and free forms, so that some volatilization
may occur.
H.6) EPA has not considered whether ~he background concentrations
of arsenic in surrounding areas which are subject to future
residential development present a greater or lesser risk
than residential development of the L-P site. (L-P)
RESPONSE: In the absence of an adequate study of background
arsenic levels in soils in the vicinity of the site, a com-
parison of site risks with "the risks posed by such back-
ground levels in surrounding areas cannot be made. The ex-
isting data do show that the arsenic levels on the log deck
are elevated relative to other areas at the plant. There-
fore, until additional data are available concerning back-
ground levels, EPA is proposing a conservative response
which is protective of public health. If sampling of sur-
face soil in the area surrounding the site (to establish
background arsenic concentrations) demonstrates that the
on-site arsenic concentrations do not exceed background
levels, then EPA would reevaluate the selected remedy.
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I.
Groundwater Monitoring
I.1) continued ground water monitoring is unnecessary since the
potential future use of ground water which constitutes the
basis for this proposed action will not occur. Further, the
best data collected by EPA indicates that formaldehyde is
not present in ground water and that arsenic concentrations
do not exceed MCLs. (L-P) .
RESPONSE: As noted earlier (see response to'comment 11),
EPA does.not agree that sufficient reasons exist to assume
that the future use of shallow ground water will not occur.
The presence of formaldehyde in shallow ground water has not
been established conclusively, and additional monitoring is
needed to settle the matter (see response to Comments G.1
and G.2). Existing data do show that the maximum observed
arsenic level in shallow ground water is below the MCL, and
thus this ARAR for ground water remedial action is met.
J.
Sourc.. of contamination
J.1) L-P has used relatively low quantities of chemicals at the
fungicide spray system, and formaldehyde was discharged from
the Hardboard plant in small quantities. (L-P)
RESPONSE: While it may be true that the quantities of
chemicals used by L-P are relatively low compared to Kop-
pers, the focus of CERCLA (Superfund) actions is on the
amount of chemicals released into the environment. Insuffi-
cient data exist to accurately determine the amount of for-
maldehyde released at the site, and the washwater discharge
from the hardboard plant is only one of several potential
sources.
J.2) The FS implies (p. 1-14) that L-P may have used arsenic,
chromium and boron. L-P never used these substances. Note
also that petroleum products are not CERCLA hazardous sub-
stances. (L-P)
RESPONSE: Samples from th9 L-P site were analyzed for ar-
senic, chromium and boron because they are present in com-
pounds used in the wood treating industry and may represent
a threat to human health and the environment. It is true
that certain petroleum products are excluded from the
definition of hazardous substances under CERCLA section
101(10).
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J.3) The soil sample from soil boring SB-1 is'not really a sur-
face soil sample. (L-P)
RESPONSE: Soil Sample SB-1 (see Figure 1.2-8 of the FS) was
collected through a hole cut in the concrete floor of the
sawmill building at a location where liquid from the fun-
gicide spray area was likely to have accumulate~ and where
joints in the concrete were observed. The sample consisted
of sail collected from beneath the concrete, and appeared to
represent the original ground surface upon which the con-
crete was poured. The purpose of this sample was to
evaluate possible pentachlorophenol ("PCP") contamination of
soil beneath the former fungicide spray area. Therefore,
SB-1 is similar to surface soil samples collected from
beneath the asphalt covering the northern third of the plant
site.
J.4) EPA should delete the statements that suggest the Koppers
facility is the sole source of the chemicals in ground water
at, and downgradient of, the L-P facility and the chemicals
detected along the Koppers/L-P boundary. (Beazer)
RESPONSE: EPA did not intend to suggest that Koppers is the
sole source of all chemicals in the ground water at, and
downgradient of, the Louisiana-Pacific site, and along the
Koppers/L-P bou~dary. In evaluating contamination at the
L-P site during the risk assessment and the Feasibility
Study, for purposes of selecting an appropriate response to
contamination at the L-P site, EPA did not include con-
.tamination which was to. be addressed by remedial actions
taken in connection with the Koppers site.
J.5) The potential source areas of PCP and other chemicals at the
L-P facility have not been adequately investigated. Wells
. placed in the shallow and regional aquifers downgradient of
the fungicide spray area may thus reveal significantly
higher concentrations of chemicals originating from the fun-
gicide spray operations. (Beazer)
RESPONSE: There were four wells installed specifically to
evaluate potential ground water contamination from pen-
tachlorophenol ("PCP") used at the L-P fungicide spray area,
which is located in the sawmill. Two wells were completed
for L-P (ML-3 and ML-4) and two were completed for EPA (W-1
and W-8). Three of the wells are located south of the saw-
mill (ML-3, ML-4, and W-1). Well W-8 is located north of
the sawmill and downgradient of the fungicide spray area.
In addition, a soil sample (SB-1) was collected from beneath
the floor of the fungicide spray area and analyzed for PCP.
Chemical tests of soil and ground water samples from these
wells and the soil samples from SB-1 detected PCP at con-
centrations below soils and ground water cleanup standards
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proposed for the Koppers site. Furthermore, no other
samples of ground water or soil from the L-P plant show con-
centrations of PCP above cleanup standards except along the
L-P/Koppers boundary (wells MW-20A), MW-20B, w-6, W-7, and
W-9). This pattern of PCP distribution indicates that l)
the L-P fungicide spray area is not a significant source of
PCP contamination, and 2) the probable source for PCP along
the L-P/Koppers boundary is on the Koppers site (see
response to comment 24).
J.6) The FS (page 1-10) states that in 1973 the Regional Water
Quality Control Board found surface water contamination at
several locations on the L-P site. Note that the Koppers
facility discharged its wastewater into the L-P log deck
pond. A comparison of concentrations in the Koppers ef-
fluent stream with those found at the L-P plant indicate
that Koppers is the source of the contamination. (L-P)
RESPONSE; Koppers discharges its wastewater into a drainage
ditch which then flows into the L-P log deck pond. This log
deck pond is one of several surface water bodies that were
present on the L-P property in 1973. Although Koppers' was-
tewater discharge may have been one source of contamination
in the log deck,pond, chemicals used by L-P were also
detected in surface waters at the L-P site.
J.7) The FS (page 1-12) should note that L-P used relatively
small quantities of PCP and that it was used in a recycle
system. The total quantities used at L-P should be compared
to the total quantities used at Koppers. (L-P)
RESPONSE; EPA did receive and evaluate information on PCP
use by both Koppers and L-P. However, the focus of our
CERCLA (Superfund) investigation is on the amount of PCP and
other contaminants released into the environment, which is
not always directly related to the volume of material used.
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