United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R09-90/049
September 1990
&EPA Superfund
Record of Decision:
Coalinga Asbestos Mine, CA
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50272-101
I REPORT DOCUMENTATION
I PAGE
1. REPORT NO.
EPA/ROD/R09-90/049
1. Recipient's AcceeeJon No.
SUPERFUND RECORD OF DECISION
Coalinga Asbestos Mine, CA
Second Remedial Action - Final
5. Report Otte
09/21/90
7. Authix(«)
8. Performing Orginiation Rept No.
». Performing Organization Name and Addree*
10. Profrct/Tiik/Work Unit No.
11. Contract(C) or Grtnt(G) No.
(C)
(G)
11 Sponsoring Organisation Hunt and Addrea*
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type ol Report t Period Covered
800/000
14.
11 Supplementary Notee
18. AbeMet (Limit: 200 word*)
The 557-acre Coalinga Asbestos Mine site, a former asbestos processing area and chromite
mine, comprises part of the Johns Manville Coalinga Asbestos Mill site in western Fresno
County, California. This rural mountainous area is used primarily for recreational
purposes.. From 1962 to 1974, asbestos ore from several local mines was processed and
orted onsite, and the resulting asbestos mill tailings were periodically bulldozed into
an intermittent stream channel. Subsequently, from 1975 to 1977, a chromite milling
operation was conducted onsite. Tailings were often washed downstream during periods of
stream flow, and the resuspension of asbestos fibers from the tailings into the air
produced a significant inhalation hazard. As a result of these activities,
approximately 450,000 cubic yards of mill tailings and asbestos ore remain onsite within
a large tailing pile. Other site features include an asbestos ore storage/loading area,
an abandoned mill building, an inactive chromite mine, filled-in chromite settling
ponds, and debris. In 1980 and 1987, State investigations indicated that the site was
contributing a significant amount of asbestos into the surface water. This site will be
remediated as two'-Operable Units (OU) . This Record of Decision (ROD) addresses the
(See Attached Page)
17. Document Aneryale a, Deecrtplon
Record of Decision - Coalinga Asbestos Mine, CA
First Remedial Action - Final
Contaminated Medium: sw
Key Contaminant: asbestos
b. UenMevt/OpwvEnded Terme
c. COSATI FWd/Graup
-. AvdlibUHy Statement
19. Security CUM (TM« Report)
None
20. Security CUM (Thl. Pige)
None
21. No. olPige*
52
22. Prio*
(See ANS»-Z3».18)
See butruetforw on fttvvrw
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-1S)
Department ol Commerce
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EPA/ROD/R09-90/049
Coalinga Asbestos Mine, CA
Second Remedial Action - Final
Abstract (Continued)
remedial action for OU2, the Johns Manville Coalinga Asbestos Mill Area. The primary
contaminant of concern affecting the surface water is asbestos.
The selected remedial action for this site includes consolidating contaminated soil and
asbestos ores within the tailing pile; grading and revegetating the tailing pile to
reduce erosion and increase stability; diverting surface-water away from the tailing
pile; improving an existing sediment trapping dam by constructing a concrete spillway;
dismantling the mill building; paving the mill access road; and implementing engineering
controls, institutional controls including deed restrictions, and site access
restrictions such as fencing. The estimated present worth cost for this remedial action
is $1,947,000, which includes a total O&M cost of $815,000.
PERFORMANCE STANDARDS OR GOAI^S .• A specific cleanup level for asbestos was not
determined due to uncertainties in sampling parameters; however, the selected remedial
action will reduce the excess lifetime cancer risk to the level of 10"4 to 10~6 .
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JOHNS-MANVILLE COALINGA MILL AREA OPERABLE UNIT
m
OF THE
JOHNS-MANVILLE COALINGA ASBESTOS MILL NPL SITE
(COALINGA MINE SITE)
RECORD OF DECISION
United States Environmental Protection Agency
Region IX - San Francisco, California
September 21, 1990
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TABLE OF CONTENTS
SECTION PAGE
Record of Decision
Declaration Statement i
Site Name and Location i
Statement of Basis and Purpose i
The Site i
Description of the Selected Remedy ii
Statutory Determinations iii
Decision Summary
1.0 Site Name, Location and Description 1
2.0 Site History and Enforcement Activities 2
3.0 Highlights of Community Participation 4
4.0 Scope and Role of the Response Action 4
5.0 Site Characteristics 5
6.0 Summary of Site Risks 6
7.0 Description of Alternatives 10
8.0 Comparative Analysis of Alternatives 14
9.0 ARARs 17
\ 10.0 The Selected Remedy 20
V" 11.0 Documentation of Significant Changes 22
12.0 Statutory Determinations 22
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RECORD OF DECISION
DECLARATION
SITE NAME AND LOCATION
Johns-Manville Coalinga Asbestos Mill Area Operable Unit of the
Johns-Manville Coalinga Asbestos Mill Site,
Fresno County, California
STATEMENT OF BASIS AND PURPOSE
This Pecord of Decision ("ROD") presents the selected remedial
action for the Johns-Manville Coalinga Asbestos Mill Area
Operable Unit ("JM Mill Area OU") of the Johns-Manville Coalinga
Asbestos Mill Site ("JM Mill Site") in Fresno County, California.
The remedy was selected pursuant to the Comprehensive Environmen-
tal Response, Compensation, and Liability Act, as amended by the
Superfund Amendments and Reauthorization Act, 42 U.S.C. Section
9601 et^ sea., ("CERCLA") and in accordance with the National Oil
and Hazardous Substances Pollution Contingency Plan, 40 c.F.R.
Section 300 et. seq.. ("NCP"). This ROD explains the factual and
legal bases for selecting the remedy for the JM Mill Area OU.
This decision is based on the Administrative Record for this
site. The attached index identifies the items that comprise the
Administrative Record.
The State of California has concurred in the selection of this
remedy.
THE SITE
The JM Mill Site includes three geographically distinct areas:
i) The JM Mill Area (Figure 1); ii) The Ponding Basin of the
California Aqueduct (Figure 2); and iii) The City of Coalinga,
California. Asbestos mining and milling waste from the JM Mill
Area has been transported to and come to be located in the other
two areas. The JM Mill Site is also known as the Coalinga Mine
Site. This operable unit ("OU") addresses the JM Mill Area ("JM
Mill Area Operable Unit").
The JM Mill Area contains an estimated 340,000 cubic meters
(450,000 cubic yards) of mine waste and mill tailings containing
high concentrations of asbestos. Actual or threatened releases
of hazardous substances from the JM Mill Area presents an im-
minent and substantial endangerment to public health, welfare, or
the environment. The response actions selected in this ROD ad-
dress this imminent and substantial endangerment.
Asbestos is a hazardous substance as defined in 42 U.S.C. Section
9601(14) and as listed in 40 C.F.R. Section 302.4. Asbestos min-
ing and milling waste is not regulated by the Resource Conserva-
tion and Recovery Act ("RCRA"). Asbestos is known to cause lung
cancer and mesothelioma in humans. Asbestos also causes other
lung diseases such as asbestosis. If asbestos is not further con-
trolled at the JM Mill Area OU, the potential for human exposure
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'(.OWJ rmOH rxn ex<«0»0 €«'!•«' 'I' "-•» 3a«* -'o
Figure 1: Detailed Site Map
Ak Stitien
LEMOOHC
I AMOVO PASA
f, OAAMAOI
Figure 2: Greater Coalinga Area
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to asbestos and the resulting increased risk to human health,
primarily through the inhalation pathway, will remain.
DESCRIPTION OF THE SELECTED REMEDY
The JM Mill Area OU is one of two designated operable units for
the JM Mill Site. The other operable unit is the clean up of as-
bestos contaminated soil in Coalinga, California by burying the
contaminated material in a vault with an impermeable cap. A ROD
for the City of Coalinga Operable Unit was signed on July 19,
1939.
Asbestos waste at t-w» ,TM Mi 1 1 A~»a on nr-ocon*-<: three major
problems: i) the release of chrysotile asbestos from the mill
area into Pine Canyon Creek during heavy rains; ii) generation of
airborne asbestos by vehicles driving in the Mill Area, on
asbestos-bearing soils and on roads; and iii) the transport of
asbestos from the Mill Area >->y vehicles which have been driven
through the Mill Area.
Clean up of the asbestos ar the JM Mill Area CU includes control-
ling the release of asbestos from the Mill Area and restricting
access to the Mill Area using engineering and institutional con-
trols. The remedy entails:
1) Constructing a cross canyon stream diversion to divert
water flow away from the tailings pile;
2) Improving the existing sediment trapping dan to
minimize the release of asbestos (approximately 340,000
cubic meters) into Pine Canyon Creefc;
3) Fencing around the mine perimeter and around the
disturbed areas to limit access;
4) Conducting a revegetation pilot project to determine
whether revegetation is a practical means of increasing
stability and minimizing erosion of the disturbed
areas ;
5) Dismantling of the mill building and disposal of
debris ;
6) Road paving or an appropriate engineering alternative; and
7) Filing -deed restrictions.
Stabilization and control of asbestos waste will minimize the
release of asbestos, thus providing long-term protection of human
health and the environment. The estimated cost of the selected
remedial action is $1.9 million.
Operation and maintenance activities will be required to ensure
the effectiveness of the response action. In the event of a
natural event such as a flood or earthquake, all repairs neces-
sary to contain the hazardous substances will be made. Because
the asbestos waste will not be treated, long-term management of
the waste will be required. EPA will review the remedial action
no less often than every five years pursuant to CERCLA Section
ii
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AL Lhis time, EPA is not proposing any 'action in the Ponding
Basin because the U.S. Bureau of Reclamation ("USER") and the
California Department of Water Resources ("DWR") are considering
actions to minimize the generation of airborne asbestos-laden
dust in this area. in 1992 EPA will evaluate whether the
USBR/DWR actions have been adequate to protect human health and
the environment and will publish a public notice of its deter-
mination. EPA will decide at that time whether further EPA ac-
tion under CERCLA in the Ponding Basin is necessary.
STATUTORY DETERMINATIONS
Pursuant to CERCLA Section 121, 42 U.S.C. Section 9621, and in
accordance with the NCP, the selected remedy for the Johns-
Manville Coalinga Asbestos Mill Area Operable Unit: (1) is
protective of human health, welfare and the environment; (2) com-
plies with Federal and State requirements that are legally ap-
plicable or relevant and appropriate to the remedial action; and
(j; is cost-effective. The selected remedy utilizes permanent
solutions and alternative treatment .(or resource recovery) tech-
nologies to the maximum exrent practicable for the JM Mill Area
OU. Treatment of asbestos contamination at the JM Mill Area OU
was determined to be impracticable based on lack of effective-
ness, technical infeasibility, problems with implementability and
cost factors.
This remedy will result in hazardous substances remaining on site
above health-based levels. Pursuant to CERCLA Section 121, 42
U.S.C. Section 9621, EPA will conduct a review within five years
after commencement of remedial action to ensure that the remedy
continues to provide adequate protection of human health and the
environment.
4
Daniel W. McGovem Date
Regional Administrator
EPA Region IX
iii
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./•RECORD OF DECISION
DECISION SUMMARY
1.0 SITE NAME. LOCATION. AND DESCRIPTION
The Johns-Manville Coalinga Asbestos Mill Site ("JM Mill Site")
includes three geographically distinct areas: i) The JM Mill
Area; ii) The-Ponding Basin of the California Aqueduct r.ear Gale
Avenue ("the Ponding Basin"); and iii) The City of Coalinga,
California. The JM Mill Site is also known as the Coalinga Mine
Site. This Operable Unit selects the remedy for the JM Mill
Area.
The JMC fli^l Area (
The JM Mill Area is a privately owned, 2.3 square kilometer
(557-acre) tract of land located in upper Pine Canyon on the
southern flank of the Joaquin Ridge in the Diablo Range, which is
part of the Coastal Range Mountains in western Fresno County,
California (Figure 2) . It is located approximately 1 kilometer
(0.6 miles) downslope from the outcrop margin of the New Idria
Formation, a diapiric serpentine plug containing naturally occur-
ring chrysotile asbestos. The nearest population center is
Coalinga (population 8250) located approximately 27 kilometers
(17 miles) to the southeast. The JM Mill Area includes asbestos
mill tailings, an asbestos ore storage/loading area, an abandoned
mill building, an inactive chromite mine (the Railroad Mine),
filled-in chromite settling ponds and debris. It is drained by
the east and vest forks of Pine Canyon Creek (See Figure 1) .
The areas adjacent to the JM Mill Area are rural. Land uses in-
clude mining, ranching, farming and recreation (camping, hunting,
hiking, mineral collecting and riding off-highway vehicles
("OHVs")).
The Ponding Basin at the California Aqueduct
The Ponding Basin is an area between State Highway 198 and Gale
Avenue to the vest of the California Aqueduct (see Figure 2). It
was designed to hold floodvaters from the Arroyo Pasajero al-
luvial fan. During heavy rains, asbestos-bearing sediments can
be washed down Pine Canyon Creek, into White Creek, into Los
Gatos Creek and eventually carried through the Arroyo Pasajero
drainage basin and deposited in the Ponding Basin and in the sur-
rounding area. During heavy flooding, asbestos-laden water has
filled the Ponding Basin and been released into the California
Aqueduct. The Ponding Basin has been designated as a part of the
JM Mill Site because it contains asbestos vhich has been
transported from the JM Mill Area. The Ponding Basin also con-
tains asbestos froa other natural and disturbed areas (including
the Atlas Asbestos Company Superfund Site or "the Atlas Mine
Site", vhich is located approximately 5 kilometers from the JM
Mill Area). The Ponding Basin is administered by the United
States Bureau of Reclamation ("USSR") and the California Depart-
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ment of Water Resources ("DWR")- Ponding basin land is used
mainly for agriculture. Huron, a community of approximately
3000, is located adjacent to the Ponding Basin. The USSR and DWR
are currently developing plans to address the Arroyo Pasajero
flooding and the impact of such flooding on the California
Aqueduct.
The Citv of Coalinaa
During the investigations of the JM Mill Site and the Atlas Mine
Site, asbestos was discovered in Coalinga, California. This as-
bestos had been shipped from the JM Mill Area and other sources
to a depot in Coalinga for eventual shipment out of Coalinga by
rail and truck. The asbestos is concentrated in a 44 hectare
(107 acre) parcel of land in the southwestern corner of Coalinga.
The City of Coalinga is an Operable Unit of the JM Mill site and
the Atlas Mine Site. A ROD was signed for that Operable Unit on
July 19, 1989 and cleanup of the asbestos began in February 1990.
Clean up is scheduled to be completed by June 1991.
2.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES
In the mid-1950's, an investigation by the California Division of
Mines and Geology indicated that the serpentine matrix of the New
Idria Formation was chrysotile asbestos. Subsequent investiga-
tion in the southeastern third of the New Idria Formation
demonstrated that the asbestos ore could be mined and milled to
produce a marketable short-fiber asbestos product. From 1959
through 1962, the Coalinga and Los Gatos Creek areas experienced
an intensive land rush for asbestos mining claims. The Southern
Pacific Railroad acquired the JM Mill Area land from the federal
government as part of a land grant under the 1871 Railway Act.
For a 25-year period, the Southern Pacific Land Company ("SPLC")
leased part of the property to the Coalinga Asbestos Company.
The Coalinga Asbestos Company, a joint venture between the
Johns-Manville Corporation ("Johns-Manville"), the Kern County
Land Company and private investors, constructed the asbestos
mill at the JM Mill Area and operated the mill from approximately
1962 to mid-1974. During the Coalinga Asbestos Company's asbes-
tos milling operations at the JM Mill Area, asbestos ore was
processed and sorted and asbestos mill tailings were periodically
bulldozed into the eastern fork of Pine Canyon Creek. Asbestos
ore was brought to the JM Mill Area from several nearby open pit
mines, including the Jensen Mine and the Christy Mine. An es-
timated 340,000 cubic meters (450,000 cubic yards) of asbestos
ore and asbestos tailings remain.at the JM Mill Area.
In November 1975, the Coalinga Asbestos Company assigned the
lease to the Marmac Resource Company/Mareco ("Marmac"), which
used the JM Mill Area to conduct a chromite milling operation.
Although all milling operations at the JM Mill Area were believed
to have ceased in October 1977, Marmac retained its lease on the
property until July 31, 1981.
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In early 1980, the Metropolitan Water District ("MWD") of
Southern California detected elevated levels of asbestos in water
samples from the California Aqueduct near Los Angeles. An exten-
sive sampling program along -the Aqueduct, conducted by the MWD in
August through September of 1980, suggested that the JM Mill Area
was one probable source of asbestos in the California Aqueduct.
Asbestos levels of up to 2500 million fibers per liter ("MFL")
were measured.
In May 1980, -EPA had the JM Mill Area inspected. Three samples
of the tailings pile were collected and analyzed using polarized
li?ht microscopy ("PLM"). The PLM analysis indicated that the
tailings contained 20% to 40% chrysotile asbestos. An emission
rate of asbestos fibers from the tailings pile was estimated to
be 0.39 to 0.69 tons per year. However, no air monitoring was
conducted to make this estimate.
On October 17, 1980, the Central Valley Regional water Quality
control Board ("CVRWQCB") and the California Department of Health
Services ("DHS") inspected the JM Mill Area to determine if waste
discharges from this facility were in compliance with state
regulations. The CVRWQCB concluded that additional corrective
measures should be taken to prevent mine- and mill-generated as-
bestos from entering the drainage basins. SPLC and Johns-Manville
submitted plans to the CVRWQCB proposing remedial actions but
Johns-Manville filed for bankruptcy before the plans could be
implemented. SPLC subsequently prepared another remediation plan,
dated August 18, 1983 and submitted it to the CVRWQCB.
On June 14, 1983, the risks posed by the JM Mill Site were rated
using the Hazard Ranking System. The JM Mill Site was approved
for listing on the NPL in September 21, 1984. Remedial
Investigation/Feasibility Study ("RI/FS") activities were in-
itiated by EPA in 1985.
The Santa Fe Pacific Railroad Company ("SFPRC" and formerly
Southern Pacific Land Company or "SPLC"), the Marmac Resources
Company, -Kern County Land Company and the Manville sales Corpora-
tion have been identified as Potentially Responsible Parties
(PRPs) at the JM Mill Site. On June 26, 1986 and June 23, 1988,
general notice letters were sent to these PRPs, notifying them of
their potential liability for clean up. On November 16, 1987,
SPLC signed an Administrative Order on Consent and agreed to con-
duct an RI/FS for the JM Mill Site. The RI and the FS were sub-
mitted to EPA on January 17, 1990 and May 3, 1990, respectively.
The problem of asbestos contamination at the JM Mill Site is part
of a larger, regional problem in the New Idria Formation, where
many other nines and disturbances related to mineral exploration
exist. EPA intends to address this regional problem in the fu-
ture .
Enforcement efforts regarding the City of Coalinga Operable Unit
3
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have resulted in a Consent Decree with Southern Pacific Transpor-
tation Company under which a clean up is being performed. No
PRPs have been sent notice letters with respect to the Ponding
Basin.
3 .0 HIGHLIGHTS OF COMMUNITY PARTICIPATION
The RI/FS Report and the Proposed Plan for the JM Mill Site were
released for public comment on May 25, 1990. These documents and
the Administrative Record were made available to the public at an
information repository maintained at the EPA Superfund Records
Center, Region IX office, San Francisco, California. The com-
r--tc. Administrative Record, which EPA used to select the remedy,
was available for public review at an information repository at
the Coalinga District Library, Coalinga, CA. In addition, three
other information repositories were established in the following
California municipalities: Avenal, Hanford, and Huron. These
three repositories contain the most important documents related
to the remedy selection such as the RI/FS, the Proposed Plan and
the Administrative Record Index. The notice of availability for
these documents was published in the Hanford Sentinel on May 25,
1990 and in the Coalinga Record on May 30, 1990.
A 30 day public comment period on the RI/FS and Proposed Plan was
held from May 25, 1990 to June 25, 1990. In the Proposed Plan,
EPA solicited requests for a public meeting but none were
received. Therefore, no public meeting was held. EPA has
prepared the attached responsiveness summary, which provides
responses to the comments submitted in writing during the public
comment period.
4 . 0 SCOPE AJJp ROM) 9F THE RESPONSE ACTION
The JM Mill Area OU is one of two designated operable units of
the JM Mill Site. The second operable unit is uncontained asbes-
tos- and nickel -contaminated soils in Coalinga, California.
The threat at the JM Mill Area OU is posed by uncontained asbes-
tos which, if not controlled, would lead to the generation of
airborne asbestos emissions. This response action is designed
to: i) limit the surface water transport of asbestos downs lope
from the Mill Area; and ii) minimize current and future airborne
asbestos emissions from the Mill Area. If asbestos carried
downstream from the JM Mill Area is deposited and then
resuspended, the resulting airborne emissions would pose a threat
to human health. Therefore, it is important to minimize the
hydraulic transport of asbestos from the JM Mill Area OU into
Pine Canyon Creek.
The remedial action selected in this ROD addresses the problem of
uncontained asbestos ore and asbestos mill tailings in the con-
text of a remote and largely rural area that is close to large
amounts of naturally occurring asbestos. The asbestos waste
will be stabilized to minimize erosion and to minimize the
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release of asbestos into the local drainage basin. In addition,
access to the disturbed areas within the Mill Area will be
limited to prevent disturbance1 of the asbestos waste and the
resulting generaL.i.un wf airborne asbestos. The abandoned mill
will be dismantled to reduce the attraction to the public and all
debris will be disposed of.
The Ponding Basin contains asbestos which has been transported
from the JM Mill Area and other natural and disturbed areas in
the New Idria Formation. EPA's risk assessment (summarized in
Section 6.0 below) suggests that a significant cancer risk may
exist for people who live and work adjacent to asbestos-
containing areas where agricultural practices put asbestos-laden
dust into the air. At this time, EPA is not proposing action in
the Ponding Basin because of actions being considered by the USSR
and the DWR to minimize the generation of asbestos-laden dust in
this area. In 1992 EPA will evaluate whether the USBR/DWR actions
are protective of human health and the environment and will pub-
lish a public nouice ot its determination. ErA will decide at
that time whether further EPA action under CERCLA in the Ponding
Basin is necessary.
Water in the California Aqueduct is known to contain high levels
of dispersed asbestos fibers. This water is used to supply
municipalities with drinking water and farmers with water for
agricultural purposes, such as irrigation. Municipalities are
required to treat drinking water to remove asbestos under the
Safe Drinking Water Act. EPA recommends that DWR evaluate the
potential, long tera public health effect of delivering
asbestos-laden irrigation water to agricultural areas of the San
Joaquin Valley.
5.0 SITE CHARACTERISTICS
Figure 1 is a site map showing major features at the JM Mill Area
OU. The JM Mill Area includes asbestos mill tailings, an asbes-
tos ore storage/loading area, an abandoned mill building, an in-
active chromite mine (the Railroad Mine), filled-in chromite set-
tling ponds and debris. The RI for the JM Mill Site included
analyses of soil and water at the mill and in the surrounding
area, as well as an ecological assessment of the Mill Area. SPLC
also prepared a regional study titled, "Offsite Source
Characterization/Regional Soil Sampling and Watershed Modeling
Report", which characterizes the occurrence and transport of as-
bestos from the JM Mill Area and other source areas in the Los
Gatos Creek Drainage Basin.
The total disturbed area at the JM Mill Area OU is approximately
10 hectares (25 acres). The main asbestos tailings pile is lo-
cated in the east fork of Pine Canyon Creek. The tailings pile
is approximately 116 meters (380 feet) across, 350 meters (1150
feet) long and 27 meters (90 feet) deep. The tailings pile is
contained on all sides except the downstream face, where it drops
off at a slope of approximately 2.5:1 for an elevation of about
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61 meters (200 feet). The slope contains extensive gullies, some
as large as five meters (15 feet) wide and three meters (10 feet)
deep.
Detailed soil sampling found levels of asbestos ranging from 61.
area percent to 80 area percent in the mine and mill waste using
Polarized Light Microscopy ("PLM") as described in the Interim
Method for the Datermi pation of Asbestos in Bulk Insulation
Samples (EPA-600/M4-82-020). Appendix 1 provides a discussion of
the various asbestos analytical techniques. Surface water
samples taken in the Mill Area were measured for asbestos using
Transmission Electron Microscopy ("TEM"). Asbestos concentra-
tions in these samples ranged from 2.0E3 to 8.0E5 million fibers
per liter ("MFL").
Regional air monitoring was conducted in the winter and summer of
1986 and 1987. Air monitoring stations were located upwind and
downwind of the JM Mill Area as well as in Coalinga and thirteen
other locations in the greater Coalinga area. Air monitoring
samples were analyzed using TEM. The data showed that elevated
levels of asbestos occur at the JM Mill Area and throughout the
Los Gatos Creek Drainage Basin and the Arroyo Pasajero Alluvial
Fan. Over time, a protective crust has formed on the tailings
pile that appears to reduce wind erosion if left undisturbed. In
addition, wind velocities in the Mill Area rarely exceed the
velocity required to entrain asbestos fibers into the air if the
surfaces are undisturbed.
winds that exceed the threshold velocity and activities that dis-
turb asbestos-bearing surfaces, such as driving a vehicle on the
tailings piles, can cause airborne asbestos emissions. Exposure
to airborne asbestos has been shown to cause cancer in humans
(see Section 6.0 below). Surface water transport modeling showed
that during heavy rains, up to five percent (5%) of the total as-
bestos yield in the Los Gatos Creek Drainage Basin is contributed
by the JM Mill Area. If asbestos is transported downslope from
the JM ifill Area by surface streams, deposited and then
resuspended, the airborne asbestos could have a negative impact
on human health and the environment.
6.0 SUMMARY OF SITE RISKS
The following discussion of site risk summarizes results of a
public health evaluation ("PHE") or risk assessment conducted as
part of "the remedial investigation. A summary of the PHE is in-
cluded as Chapter 10.0 and the complete PHE text is included as
Appendix M in the RI. Because of certain similarities between the
Atlas Mine Site and the JM Mill Site with respect to the con-
taminant and the media of concern, EPA prepared one PHE for both
sites. However, where possible, the excess cancer risk due to
the Mine and Mill Areas' individual contribution of asbestos was
calculated separately.
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Asbestos is a generic term referring to two groups of naturally-
occurring hydrated silicate, .minerals .having a fibrous crystalline
structure, the amphiboles and the serpentines. The asbestos
found in the New Idria Formation is the serpentine mineral
chrysotile. Asbestos fibers are widely used for their high ten-
sile strength and flexibility and for their noncombustible, non-
conducting, and chemical-resistant properties. The fibers have
been used in insulation, brake linings, floor tile, plastics, ce-'
ment pipe, paper products, textiles, and building products,
Asbestos is the contaminant of concern at the JM Mill Site. As-
bestos is one of the few substances which is known to cause can-
cer in humans. Asbestos exposure can also cause other lung dis-
eases, such as asbestosis. EPA considers carcinogens to be non-
threshold in nature, that is, any amount of a human carcinogen in
the environment represents a cancer risk to the exposed popula-
tion. Asbestos has been the subject of numerous epidemiology
studies. Exposure to asbestos has been positively linked to as-
bestosis, lung cancer, and mesothelioma. Also associated with
asbestos exposure in some studies are cancers of the larynx,
pharynx, gastrointestinal tract, kidney, and ovary/ as veil as
respiratory diseases such as pneumonia.
The adverse human health effects from exposure to asbestos are
extremely serious. A full discussion of the health effects of as-
bestos is found in the EPA document Airborne Asbestos Health As-
sessment Update. June 1986. Remedial action is warranted to
mitigate the exposure to a carcinogen that is present as a result
of human activity. Actual or threatened releases of hazardous
substances from this OU may present an imminent and substantial
endangerment to public health, welfare, or the environment.
Major sources of asbestos at the JM Mill Area are contaminated
soils, unprocessed asbestos ore and asbestos mill tailings. In
localized areas unpaved roads and trails may also be a source of
asbestos. The three media of concern are air, surface water and
soil.. Asbestos is not soluble in water and is not transmitted to
ground water.
There are two general routes of exposure to asbestos at the JM
Mill Area: inhalation and ingestion. Inhalation is the.exposure
pathway of greatest concern to human health because this pathway
has been positively linked to cancer in humans. While not of
primary importance, ingestion exposure to asbestos may also be
associated with an increased risk of cancer.
Potentially exposed populations include the following groups: i)
individuals who use the JM Mill Area for hunting and ranching;
ii) individuals who live in close proximity to the JM Mill Area;
and iii) the populations of communities in Fresno and San Benito
Counties such as Huron, Coalinga, Idria, Five Points, Stratford,
Kettleman City, Priest Valley, Lonoak, Panoche and Avenal.
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In the greater New idria-Coalinga study region, a wide variety of
potential regional sources of asbestos may contribute to asbestos
concentrations in the air. These regional sources include other
mines and disturbed areas, unpaved roads, trails and naturally
occurring serpentinite soils in the New Idria Formation. The risk
assessment evaluated exposure to ambient levels of asbestos due
to all potential regional sources and also to asbestos present in
the air due to the JM Mill Area alone. It is difficult to
directly measure the individual contribution of asbestos emis-
sions from the JM Mill Area to ambient air monitoring results be-
cause of the nearby sources in the New Idria Formation. There-
fore, models were used to estimate the concentration of asbestos
in air which may occur if the only sources of asbestos in the
region were wind erosion of tailings piles and mine surfaces and
vehicle traffic on the unpaved road running through the JM Mill
Area. The air monitoring data were used in conjunction with his-
torical Total Suspended Particulate ("TSP") data to obtain annual
average air concentrations in various locations with all sources
considered. The TSP data account for time periods when the
threshold wind velocity for entrainment was exceeded. Section
5.2.1 of the RI for the Atlas Mine Site provides a more detailed
discussion of the air modeling methods.
The highest risk posed by the JM Mill Area is correlated to
activity-related exposure, such as exposure due to disturbance by
motorized vehicles of asbestos-bearing surfaces. This exposure
could occur either at the Mill Area or off-site in areas to which/
asbestos from the Mill Area has been transported. Exposure point
concentrations were calculated using concentrations of asbestos
in soils, nine surfaces and nine tailings in conjunction with es-
timated enission rates and an air dispersion model. Emissions of
asbestos-contaminated dust generated by off-road vehicle ac-
tivities and by agricultural tilling were estimated using equa-
tions presented in EPA's Compilation of Air Pollutant Emission
Factors for Stationary Point and Area Sources (EPA, 1985c). The
air dispersion model was a simple box model which defines a cer-
tain volume of air (the box) in which emissions from the area
sources'are present. The box model assumes that wind speed and
direction are constant within the box and that the air is
uniformly mixed. For exposure to ambient air at the JM Mill
Area, it was assumed that a 20-year-old-male will be present for
8 hours per day, 52 days per year, for 10 years, to yield an
average continuous exposure duration of 0.47 years (the average
case). For exposure to air during off-road vehicle activity, it
was assumed that a 20-year old male drives for three hours per
day, 16 days per year for five years (the average case). Table 1
summarizes the average and maximum exposure assumptions use for
the various activity related exposures. For both types of ac-
tivity, the EPA unit risk factor of .21386 (PCM fibers/cubic
centimeter)l.OE-1 was used.
Experiments conducted by the California Department of Health
Services ("DHS") in 1985 show that a pickup truck driving on un-
paved asbestos-contaminated soil can produce asbestos dust con-
8
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TABLE 1
SUMMARY OF EXPOSURE PARAMETERS
INHALATION DURING OPF HIGHWAY VEHICLE ACTIVITY
PARAMETER VALUE
EXPOSURE PARAMETER AVERAGE MAXIMUM
Age At Onset of Exposure (Yrs) 20 20
Total Years Exposed ... 5 5
Frequency of Exposure (Hrs/Yr) 43 160
INHALATION DURING HUNTING, CAMPING OR HIKING
PARAMETER VALUE
EXPOSURE PARAMETER AVERAGE MAXIMUM
Age At Onset of Exposure (Yrs) 20 20
Total Years Exposed 10 20
Frequency of Exposure (Hrs/Yr) 416 832
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Generations in the air that pose a potential health risk to in-
dividuals close to the activity. A discussion of this experiment
has been included in the Administrative Record for the JM Mill
Area uU.
The excess lifetime cancer risk from drinking asbestos-
contaminated water from the California Aqueduct was not found to
be significant. The risk estimates were calculated assuming in-
gestion of two liters of water per day for a 70 year period by an
adult weighing 70 kilograms (154 pounds). EPA's unit risk factor
of 1.4E-13 (fibers/liter)1.0E-l was used (EPA, 1985b).
•*\'~~.x* lifetime cancer risks are determined by multiplying the
intake level with the cancer potency factor. These risks are
probabilities that are generally expressed in scientific notation
(e.g., l.OE-6). in this risk assessment, an excess lifetime can-
cer risk of l.OE-6 indicates that, as a plausible upper bound, an
individual has a one in one million chance of dying from cancer
as a result of site-related exposure to a carcinogen over a 70-
year lifetime under specific exposure conditions. The estimated
excess lifetime cancer risk for individuals hiking, camping or
hunting at or nearby the JM Mill Area varied from l.OE-6 to
6.0E-6 under average and maximum exposure conditions, respec-
tively. The estimated excess lifetime cancer risk for in-
dividuals driving a four-wheel-drive truck on the JM Mill Area
varied from 8.0E-4 to 4.0E-1 under average and maximum exposure
conditions, respectively. (When SFPRC data are used to calculate
the latter risk range, the risk varies from l.OE-4 to l.OE-1 for
average and maximum exposure conditions, respectively). The es-
timated excess lifetime cancer risk for individuals ingesting un-
treated California Aqueduct water, contaminated with asbestos
from all sources in the Los Gates Creek Basin, varied from 2.0E-6
to 4.0E-5 under average and maximum exposure conditions, respec-
tively. However, it should be noted that municipalities are re-
quired to filter drinking water under the Safe Drinking Water
Act, thereby further reducing exposure to asbestos.
'. \
When evaluating risk from asbestos in the environment, there are
sources of uncertainty associated with asbestos measurement that
make quantifying the risk difficult. One of these sources of un-
certainty is the difficulty of obtaining accurate and precise
measurements of asbestos concentrations in soil, air, and water.
For example, all risk assessments require an accurate and precise
measurement of contaminant concentration. When a gaseous or
soluble chemical is the contaminant of concern, the measurement
of only one parameter, concentration, is sufficient to establish
how much of that contaminant is present in a given sample.
However it is significantly more complex to measure the con-
centration of particulates accurately and precisely, especially
fibrous particulates, because many more parameters must be ac-
counted for. When measuring spherical particles the following
parameters must be measured: i) the overall particle size dis-
tribution; ii) the concentration of each individual size
category; and iii) the change in concentration of each size
-------
category in differenc parts of a dust cloud. When measuring
fibrous particulates such .ac^asbestos, the parameters become even
more complex. The length1'and diameter of each particle must be
measured along witn tne distribution of complex shapes (such as
bundles, clusters and matrices). The concentration of each par-
ticle shape must be established, along with the settling velocity
of different fiber shapes. Finally, because asbestos analysis
involves use of an optical or electron microscope, the relative
experience and fatigue of the analyst can influence the ultimate
accuracy and precision of a given analysis.
Many of the epidemiology studies which established the link be-
tween the inhal at.: on of asbestos anrj ranrer used phase contrast
microscopy ("PCM") techniques to measure asbestos concentration.
However/ PCM is considered inadequate for the analysis of a short
fiber mineral such as chrysotile and for the analysis of non-
occupational levels of asbestos. Many of these studies were done
before TEM techniques wer«s available. Most studies today use TEM
as the "state or tne art" analytical technique tor measuring air-
borne asbestos concentrations (see Superfund Method for the
Determination of Asbestos in Ambient Air. EPA/540/2-90/005a and
005b, May 1990). In the RI, the ambient air samples and surface
water samples were measured using TEM while the soil samples were
measured using PLM. Limited TEM analyses of the soils samples
were used for confirmation. To use TEM data in quantitative risk
assessments, one must convert TEM data to PCM Equivalent ("PCME")
data using a conversion factor. There are a variety of ways to
perform this conversion. Whenever conversions of this type are
done, the ability to quantify risks is decreased.
The PHE also discusses the environmental assessment of the JM
Mill Area. From an ecological standpoint, although there are
significant impacts associated with the destruction of habitats
by the mining and milling activities in the JM Mill Area, the
direct effects of asbestos on wildlife appear relatively insig-
nificant. These impacts will be partly mitigated by reclamation
of the disturbed areas using native vegetation. Three sideslope
seeps ("wetlands") were identified at the JM Mill Area. These
wetland ^areas derive their water supply mainly from local
groundwater. The selected remedy will not negatively impact the
wetlands because groundwater is not being affected. In fact, the
selected remedy will be beneficial for one of the wetlands im-
mediately downslope from the main tailings pile, because the
selected remedy will minimize the possibility of a slope failure
on the tailings pile resulting in movement of the tailings over
the wetland area.
7.0 DESCRIPTION OF ALTERNATIVES
EPA evaluated potential remedial action alternatives for the
Johns-Manville Coalinga Asbestos Hill Area OC in accordance with
CERCLA Section 121, the National Contingency Plan ("NCP"), (in
particular, 40 C.P.R. Section 300.68), and the Interim Guidance
on Superfund Selection of Remedy. December 24, 1986 (OSWER Direc-
10
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tive No. 9355.0-19). The Resource Conservation and Recovery Act
("RCRA") does not apply to asbestos and its Land Disposal
Restrictions do not apply to asbestos mining and milling waste.
The first step in evaluating potential remedial action alterna-
tives was to determine, based upon JM Mill Area OU characteris-
tics, what set of response actions and associated technologies
should be considered. An example of this preliminary determina-
tion (or "scoping") was the elimination of biological treatment
from further ^consideration because biological processes capable
of detoxifying asbestos contaminated soil do not exist. Section
2.4 of the FS discusses the scoping process in more detail.
The next step in the selection of remedy process was assembling
the remaining technologies and/or disposal options into general
remedial action alternatives. Pursuant to OSWER Directive No.
9355.0-19, remedial action alternatives are to be developed rang-
ing from those that would eliminate the need for long-term
management (including monitoring) at the JM Mill Area OU to al-
ternatives involving treatment that would permanently reduce the
mobility, toxicity or volume of the hazardous substances(sj as
their principal element:. In addition, containment options in-
volving little or no treatment and a no action alternative are to
be developed. The remedial action alternatives developed in the
FS were:
Alternative 1: No Action
Alternative 2: Road Paving; Mill Dismantling; Deed
Restriction;
Alternative 3: Access Restriction plus Alternative 2;
Alternative 4: Sediment Trapping Dam Upgrade; Additional
Sediment Trapping Dans; Stream Diversion
Upgrade; Revegetation plus Alternative 3;
Alternative 5: Grading; Cross Canyon stream Diversion;
Sediment Trapping Dam Upgrade; Revegetation
plus Alternative 3;
Alternative 6: 0.5 Foot Soil Cap plus Alternative 5
Alternative 7: 2.0 Foot Soil Cap plus Alternative 5
Alternative 8: Removal of Haste to Off-Site Landfill
Alternative 9 Soil Fusion Using Thermal Treatment
All of the costs and implementation times presented below are es-
timates. The cost of monitoring is not included in the cost es-
timates for Alternatives 2 through 7 and Alternative 9. Opera-
tion and maintenance estimates are for a 30 year period. Details
of how the cost estimates were calculated are included in the FS.
The Proposed Plan did not specifically mention design criteria
for the stream diversion structures, sediment trapping dams or
protecting the tailings piles. As a result of comments by the
California Department of Health Services, some design criteria
have been added to this ROD (see Section 10.0). The Proposed
Plan also specified that the road through the Mill Area would be
paved. The ROD allows appropriate engineering alternatives to
v
11
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road paving, such as annual road maintenance.
Alternative 1; MO Action**"""$' ' '""'"'' ^'' -l'
The Superfund program requires that the "No Action" alternative
be evaluated at every site to establish a baseline for com-
parison. Under this alternative, no remedial action would be
taken but a regular program of site monitoring would be started.
This monitoring program would include periodic site inspections,
sampling of surface water and airborne asbestos levels in the JM
Mill Area; as-well as aerial monitoring. Capital, O&M (operation
and maintenance) and present worth costs are, respectively, no
cost, $93,000 and $93,000. Alternative 1 would require 3 months
to implement.
Alternative 2: Road Paving. Mill Dismantling. Deed Restriction
Under this alternative, in addition to monitoring of the JM Mill
Area, either the road through the Mill Area would be paved or
annual road maintenance will be performed to reduce the genera-
tion of airborne asbestos emissions. The mill building vould be
dismantled to reduce the Mill Area's attraction to the public. A
deed restriction would be placed on the property to ensure that
monitoring and other operation and maintenance activities are
carried out. Capital, O&M and present worth costs are, respec-
tively, $186,000, $171,000 and $357,000. Alternative 2 is es-
timated to require 6 months to implement.
Alternative 3; Access Restriction plus Alternative 2
In addition to all elements of Alternative 2, the fences cur-
rently in place to prevent unauthorized use of the road through
the JM Mill Area would be improved. Barriers vould be erected
around the disturbed areas to discourage access by four-wheel
drive vehicles. Signs would be posted throughout the Mill Area
area to warn of an asbestos hazard. The property owners have al-
ready put up a number of warning signs on the perimeter of the
property. Capital, O&M and present worth costs are, respec-
tively, $350,000, $300,000 and $650,000. Alternative 3 is es-
timated to require 12 months to implement.
Alternative 4: Sediment Trapping Dam Upgrade; Additional
Sediment Trapping Dans; Stream Diversion
Upgrade; Reveqetation plus Alternative 3
In addition to elements of Alternative 3, the existing BLM stream
diversion vould be improved to protect it against potential
failure. Th« existing sediment trapping dam would be improved by
constructing a concrete spillway that would protect the dam
against overflow and subsequent failure. Several small sediment
trapping dams would be constructed downstream to make the exist-
ing dam more effective in reducing the potential for asbestos
release into the local drainage. A pilot study would evaluate
whether native vegetation could be established on the disturbed
12
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areas. A revegetation project will be implemented if it is found
to be technically feasible and cost effective. Capital, O&M and
present worth costs are, respectively, $740,000, $598,000 and
$1,338,000. Alternative 4 is estimated to require 24 months to
implement.
Alternative 5: Grading; Cross Canyon Stream Diversion;
Sediment Trapping; Dam Upgrade; Reveoetation
plus Alternative 3
This alternative includes several elements of Alternative 4. A
cross canyon stream diversion would be constructed to divert
flows away from the tailings pile. This would remove the largest
source of water draining through the tailings pile and eliminate
the need for additional small sediment trapping dams downstream
from the Mill Area. The grading would reduce the slope of the
tailings pile and improve its stability. The existing sediment
trapping dam would be improved with a concrete spillway and the
revegetation pilot study would be started as described in Alter-
native 4. All other elements of Alternative 3 would be I.T.Cla-
mented. Capital, O&M and present worth costs are, respectively,
$1,130,000, 815,000 and 1,947,000. Alternative 5 is estir.atac: -.2
require 24 months to implement.
Alternative 6; 0.5 Foot Soil Cap plus Alternative 5
In addition to the elements of Alternative 5 that control erosion
and run-off, Alternative 6 includes the construction of a
vegetated soil cover on the asbestos tailings. This vegetated
soil cap would be constructed by first reshaping the tailings
piles and then covering them with six inches (15.24 centimeters)
of fertile soil cover. (The revegetation proposal in Alternatives
4 and 5 do not include this soil cover.) Vegetation would then
be established on the soil cover. Capital, O&M and present worth
costs are, respectively, $3,092,000, $1,012,000 and $4,106,000.
Alternative 6 is estimated to require 24 months to implement.
Alternative 7: 2.0 Foot Soil Cap plus Alternative 5
In addition to elements of Alternative 5 that control erosion and
run-off, Alternative 7 includes the construction of a 2-foot (61
centimeter) vegetated soil cap. Capital, O&M and present worth
costs are, respectively, $6,162,000, $1,485,000 and $7,648,000.
Alternative 7 is estimated to require 24 months to implement.
Alternative 8: Removal of Waste to an Off-Site Landfill
340,000 cubic meters (450,000 cubic yards) of asbestos con-
taminated material would be excavated and transported to an off-
site landfill permitted to receive asbestos waste. Nearly all of
the asbestos would be excavated and the need for long-term
monitoring and maintenance of the mines and stockpile areas would
be eliminated. Capital, O&M and present worth costs are, respec-
tively, $712,000,000, no cost and $712,000,000. Alternative 8 is
13
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estimated to require 54 months to implement.
. • - •• ; •-•• •• . •:,', fi • • •
Alternative 9: Soil Vitrification using Thermal Treatment
340,000 cubic meters (450,000 cubic yards) of asbestos waste
materials would be vitrified using a thermal treatment process.
The asbestos material would be converted from a soil into an in-
ert, stable glass product using electrodes which would heat the
soil to extremely high temperatures. The soil would be heated
above its melting point and eventually converted to the glass
product. Capital, O&M and present worth costs are, respectively,
$289,000,000, no cost and $289,000,000. Alternative 9 is es-
timated to require 144 months to implement.
8.0 SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
This section provides an explanation of the nine (9) criteria
used to select the remedy, and an analysis of the nine remedial
action alternatives in light of those criteria, highlighting the
advantages and disadvantages of each of the alternatives.
Criteria
The alternatives were evaluated based on the nine key criteria
which directly relate to the factors that CERCLA and the NCP, 40
CFR Section 300.430, mandate that the Agency assess in selecting
a remedy. These criteria are:
(1) overall protection of human health and the environment,
which addresses whether a remedy provides adequate protection and
describes how risks posed through each pathway are eliminated,
reduced or controlled through treatment, engineering controls or
institutional controls;
(2) compliance with applicable or relevant and appropriate
requirements (ARARs), which addresses whether a remedy will meet
all of the applicable or relevant and appropriate Federal and
State laws and/or justifies a waiver;
(3) long-tan effectiveness aad permanence, which refers to
expected residual risk and the ability of a remedy to maintain
reliable protection of human health and the environment over
time, once clean-up goals have been met;
(4) reduction of toxioity, mobility or volume through treat-
ment, which addresses the anticipated performance of the treat-
ment technologies a remedy may employ;
(5) short term effectiveness, which addresses the period of
time needed to achieve protection and any adverse impacts on
human health and the environment that may be posed during the
construction and implementation period, until clean-up goals are
achieved;
(6) implementability, which is the technical and administra-
tive feasibility of a remedy;
(7) cost, which includes estimated capital and O&M costs, as
well as present-worth costs;
14
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(8) state acceptance, which indicates the support of the
State agency for the selected remedy; and
(9) community acceptance, which summarizes the public's
general response to the RI/FS and Proposed Plan.
Because there is no cost-effective treatment technology for
asbestos-containing mining and milling material at this OU,
criterion number four is not directly relevant to a choice among
alternatives. However, the alternatives were compared with
respect to their ability to minimize the mobility (through the
air or surface water pathways) of the asbestos-containing
material.
Analysis of the Alternatives
Overall Protection. Because Alternative 1, the "no action" al-
ternative, is not protective of human health and the environment,
it is not considered further in this analysis as an option for
the JM Mill Site. Alternative 2 would be inadequate in protect-
ing human health and the environment since it would not reduce
human contact with asbestos. Alternative 3, by restricting ac-
cess to the JM Mill Area, would be protective of human health at
the JM Mill Area, by controlling the significant risk from in-
halation of asbestos-contaminated air but would not be protective
at the areas downstream from the OU. Alternatives 4 through 7
would all provide adequate protection of human health, both at
the JM Mill Area and downstream, by minimizing human contact with
asbestos through engineering controls and institutional controls.
Alternatives 4 through 9 would also be protective of the environ-
ment by preserving the wetlands present at the JM Mill Area. Al-
ternative 9 is the only option that utilizes treatment and would
probably provide the most protection to human health and the en-
vironment. Alternative B would provide protection similar to Al-
ternative 9 but would require off-site transportation and dis-
posal of the asbestos.
Compliance with ARARs. Alternatives 4 through 9 would meet the
respective applicable or relevant and appropriate requirements of
Federal and State environmental laws. Alternative 3 would comply
with the specifications in 40 CFR Section 61.153(b) and Section
61.156(b) but would not comply with the remaining identified
ARARs. Alternative 7 would comply with the specifications 'in 40
CFR Section 61.153(a)(2). Alternatives 1 does not comply with any
ARARs. Alternative 2 would comply with the California Health and
Safety Code, Section 2S232(a)(l) and (2).
Lona-tera Effectiveness and Permanence. Alternative 5 would
reduce the amount of asbestos-contaminated material released into
the air and the surface water in the JM Mill Area. By restricting
access to the Mill Area, Alternative 3 would reduce the long-term
risk of exposure to asbestos-contaminated air only in the Mill
Area. For this criterion, Alternative 4 is comparable to Alter-
native 5. Long term effectiveness will depend on proper main-
tenance of diversion structures and other engineered elements.
15
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The engineered elements of the preferred alternative will be
designed to take maximum advantage,,.of the natural systems and to
minimize operation and maintenance needs.
Alternative 9 provides the greatest amount of long-term effec-
tiveness and permanence. Alternative 8 would remove all waste to
a landfill permitted to accept asbestos, thereby eliminating the
long-term risk of exposure at the JM Mill Area. As with all
landfills, the containment system may fail or need to be
retrofitted or replaced. Therefore, a risk will remain at the
landfill site and long-term effectiveness will be dependent on
operation and maintenance at that location.
Alternatives 6 and 7 provide protection to receptors from asbes-
tos exposure that is comparable or slightly greater than Alterna-
tives 4 and 5. Alternative 7 offers a higher degree of per-
manence because a 2-foot thick cap will provide an increased
resistance to erosion. The excavation of soil to construct
vegetated caps in Alternatives 6 and 7 could cause significant
disruption in the habitat value of nearby areas. Alternative 2
would not provide.long-term effectiveness and permanence.
Reduction of Toxicitv. Mobility or Volume of the Contaminants
Through Treatment. Only Alternative 9 would treat the waste to
reduce the toxicity and mobility of the asbestos. Alternatives 2
through 8 rely on institutional controls or engineering controls
to reduce the mobility of the asbestos to varying degrees. Tech-
nology is not currently available that would reduce the volume of
asbestos contaminated soils.
Short-Term Effectiveness. Alternatives 2 and 3 would quickly
reduce direct human contact with asbestos at the JM Mill Area and
would provide the most effective short-term protection. Alterna-
tives 4 through 7 would have a minor, short term risk of exposure
for workers at the JM Mi.Tl Area. Alternative 9, because of its
greater implementation time, would include a more serious short
term risk to on-site workers. Alternative 8 would subject the
surrounding community to the possibility of accidental spillage
during transport of the contaminant from the JM Mill Area.
Implementabilitv. Alternatives 2, 3, and 8 would have no un-
usual technical difficulties that could delay implementation.
For Alternatives 4 and 5, the implementability of the revegeta-
tion component will be tested in a pilot project. The other ele-
ments of Alternatives 4 and 5 should not present an implemen-
tability problem. Borrow sources are areas where clean soil is
removed for use as a cap on the contaminated areas. Alternatives
6 and 7 would face a technical difficulty in finding adequate
borrow sources near the site for capping and could face major ad-
ministrative difficulties in getting permits from local and
county development agencies to exploit nearby borrow sources
without adversely impacting the Mill Area habitat value. Alter-
native 9 could face technical difficulties with the process sys-
tem designed to fix the waste material and would also require a
16
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pilot study prior to implementation. These difficulties would
include supplying sufficient electric power to the JM Mill Area
and logistical problems related to servicing a complex system in
a remote area. Alternative 8 might face administrative dif-
ficulties in getting permits from state and federal agencies for
transporting the asbestos material on public roads.
Cost. All of the following cost figures are estimates of present
worth cost. The cost of Alternative 1 is $93,000 (for continued
monitoring). . Alternative 2 has a cost of $357,000. The cost of
Alternative 3 is $554,000. Alternative 4 has a cost of
$1,340,000. Alternative 5 has a cost of $1,950,000. Alternative
£ h^s a cost of $4,100,000. Alternative 7 has a cost of
$7,650,000. The highest cost alternative is Alternative 8 at
$712,000,000. The cost of Alternative 9 is $289,000,000. For
Alternatives 2 through 5, the costs outlined above do not include
the cost of continued monitoring.
State Acceptance. The State of California has concurred in EPA's
selection of the preferred alternative.
Community Acceptance. I PA did not receive any concents fron co=-
r.unity members on the Proposed Plan for the JM Mill Site. The
PRP who conducted the RI/FS supports the selected remedy. Mar-
mac, another PRP, has indicated a preference for Alternative 3
plus grading to stabilize the tailings pile.
9.0 APPLICABLE. QR BBTJgVftNT AND APPROPRIATE REQUIREMENTS fARARsl
Under Section 121(d) (1) of CERCLA, 42 U.S.C. Section 9621(d)(l),
remedial actions must attain a degree of clean-up which assures
protection of human health and the environment. Additionally,
remedial actions that leave any hazardous substance, pollutant,
or contaminant on-site must meet a level or standard of control
that at least attains standards , requirements, limitations, or
criteria that are "applicable or relevant and appropriate" under
the circumstances of the release. These requirements, known as
"ARARs", may be waived in certain instances, as stated in Section
121(d)(4) of CERCLA, 42 U.S.C. Section 9621(d)(4).
"Applicable" requirements are those clean-up standards, standards
of control and other substantive environmental protection re-
quirements, criteria, or limitations promulgated under federal or
state lav that specifically address a hazardous substance, pol-
lutant or contaminant, remedial action, location, or other cir-
cumstance at a CERCLA site. "Relevant and appropriate" require-
ments are clean-up standards, standards of control and other sub-
stantive environmental protection requirements, criteria, or
limitations promulgated under federal or state law that, while
not "applicable" to a hazardous substance, pollutant, con-
taminant, remedial action, location, or other circumstance at a
CERCLA site, address problems or situations sufficiently similar
to those encountered at the CERCLA site that their use is well-
suited to the particular site. For example, requirements may be
17
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relevant and appropriate 'if"'they'--would be "applicable" but for
jurisdictional restrictions associated with the requirement.
The determination of which requirements are "relevant and ap-
propriate" is left to EPA's discretion. EPA may look to the type
of remedial actions contemplated, the hazardous substances
present, the waste characteristics, the physical characteristics
of the site, and other appropriate factors. It is possible for
only part of a requirement to be considered relevant and ap-
propriate. Additionally, only substantive requirements need be
followed. If no ARAR covers a particular situation, or if an
ARAR is not sufficient to protect human health or the environ-
ment, then non-promulgated standards, criteria, guidance, and ad-
visories must be used to provide a protective remedy.
Types of ARARs
There are three types of ARARs. The first type includes
"contaminant specific" requirements. These ARARs set limits on
concentrations of specific hazardous substance, pollutants, and
contaminants in the environment. Examples of this type of ARAB.
are ambient water quality criteria and drinking water standards.
The second type of ARAR includes location-specific requirements
that set restrictions on certain types of activities based on
site characteristics. These include restriction on activities in
wetlands, floodplains, and historic sites. The third type of ARAR
includes action-specific requirements. These are technology-
based restrictions which are triggered by the type of action un-
der consideration. An example of an action-specific ARAR is the
Occupational Safety and Health Act ("OSHA") which sets permis-
sible levels of exposure to asbestos for workers.
ARAR Identification Process
ARARs must be identified on a site-specific basis from informa-
tion about specific chemicals at the site, specific features of
the site location, and actions that are being considered as
remedies.
ARARs identified for the JM Hill Area 013 address emission of as-
bestos fibers from contaminated soils, inhalation of asbestos
fibers, disposal of asbestos contaminated soils, protection of
endangered species, and protection of wetlands.
Contaminant-Specific ARARs For Asbestos:
1. cyean Air Act. National Emission Standard for Hazardous Air
Pollutants ffflSSHAPal
Asbestos was first designated as a hazardous air pollutant unde
the Clean Air Act in 1971. The National Emission Standard fo
Hazardous Air Pollutants ("HESHAPs") for asbestos found at 4
C.F.R. Section 61.152 and 40 C.P.R. Section 61.156 are ARARs fc
the implementation of the remedy at this Site. 40 C.F.R. Sectic
18
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61.153 is an ARAR for the completion of the remedy at the Site.
2. California ftjr Resources Act. Health and Safety Code. Divi-
sion 26. section 39000 et sea. 17 CCR. Part 3. Chapter 1.
10 standard
The Fresno County Air Pollution Control District has adopted PM
10 as a particulate matter standard. This PM 10 standard means
that ambient levels of'.particulate matter greater than 10 microns
in length shall not exceed 30 micrograms per cubic meter (annual
average) or 50 microgramsper cubic meter over a 24 hour period.
Location-Specific ARARs:
Because the Site is located in an area that contains endangered
species (i.e., the kit fox and the blunt-nosed leopard lizard),
the following requirements are ARARs for the Site:
1. The Endangered Species Act of 1973. 16 U.S.C. Section
1536fa-d)
Generally, when a project potentially impacts an endangered
species or critical habitat, activities carried out by Federal
agencies should not jeopardize the continued existence of an en-
dangered species or cause adverse modifications of critical
habitat.
2. USFWS Mitigation Policy fFR 7644-7663. Vol 46. Mo. 15. January
19811.
This policy is triggered in accordance with the Fish and Wildlife
Act of 1956, Fish and Wildlife Coordination Act, Watershed
Protection and Flood Prevention Act and the National Environmen-
tal Policy Act. The mitigation policy defines resource
categories and establishes mitigation goals and guidelines for
each. Guidelines to achieve the goal include avoiding or mini-
mizing habitat loss, immediate rectification or reduction of
habitat loss or replacement of habitat in kind.
3. Federal Water Pollution Control Act. Section 404fbim. 33
U.S.C. Section I344fbim.
This statute is designed to ensure that if no practicable alter-
native to impacting waters of the United States including wet-
lands exists, any unavoidable, adverse impact on the wetlands
must be mitigated.
4. California Hazardous Waste Control Laws. Health and Safety
Code. Div. 20. Chanter 6.5. Section 2S220-2S241 at sea, and 22
CCR. Div. 4. Chapter 30. Section 66001 et seq
The actual substantive restrictions contained in Section
25232(a) (1) and (2) are an ARAR. However, the procedural re-
19
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quirements related to notice, hearing and the mechanisms for im-
plementing deed restrictions do not fall within the definition of
an ARAR. CERCLA Section 121, 42 U.S.C. 9621.
Specific
1. Occupational Saffgtv and Health Act f"OSHA"l
OSHA has set a permissible exposure limit ("PEL") for all asbes-
tos fibers at 0.2 fiber per cc ("f/cc") for occupationally ex-
posed workers and an' "action level" (the level above which
employers must initiate compliance activities) of 0.1 f/cc as an
S -hour time weighted average (51 C.F.R. Section 22612 (1336)).
While this standard was meant for occupational exposure (8 hours
per day, 40 hours per week, 52 weeks per year) and not for con-
tinuous ambient exposure, it provides an upper threshold for
evaluating permissible ambient exposure limits. In other words,
a concentration of .2 PCM fibers per cc of respirable air or less
is not permissible for ambient exposure, since this requirement
is applicable or relevant and appropriate for exposure during the
cleanup of this Site.
2. California Porter Cologne Water Quality Act. 23 CCR, Chaster
3: Subchapter 15. Article 7 - Mining Waste Management. Section
2570-2574. Specifically 23 CCR Section 2572 (b) . 23 CCR Section
2572fhimfAl. 23 CCR Section 2572fhl(3). 23 CCR Section 2546fd)
and 23 CCR Section 2546
This state act contains regulations establishing waste management
requirements for all mining vaste. The act's construction stan-
dards require accommodation of 2 5 -year, 24-hour storm run-off
controls in design criteria for the drainage and diversion struc-
tures at the Mill Area as well as 100 year peak stream flow
protection for all waste piles at this site. These requirements
are applicable and relevant and appropriate for remedial action
at this site.
10.0 THE SELECTED REMEDY
\
N-.
Alternative 5, consisting of grading, cross canyon stream diver-
sion, improvements to the existing sediment trapping dam, access
restrictions, deed restrictions, revegetation pilot study, road
paving or an engineering alternative, and mill dismantling, is
the selected remedy for the JM Mill Area OU. The grading will
reduce the slope of the tailings pile and improve its stability.
A stream diversion will be built to channel surface water away
from the tailings piles, thereby reducing erosion and transport
of asbestos into Pine Canyon Creek. An existing stream diversion
upslope from the main tailings pile will be improved. The exist-
ing sediment retention daa will be improved with a concrete
spillway. A pilot study will evaluate if native vegetation could
be established on the disturbed areas. If revegetation is found
to be technically feasible, the disturbed areas will be reclaimed
with vegetation. The disturbed areas will be fenced off. The
20
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mill building will be dismantled and disposed of along with other
debris in the mill area. The road through the Mill Area will be
?•*">?* cr an alternative will be adopted to suppress dust. A deed
restriction will limit land use and prevent disturbance of the
contaminated material left at the Mill Area. Visual inspections,
both on the ground and from the air, will be required to ensure
the integrity of the engineering and institutional controls.
The goal of the selected remedy is to maintain the current effec-
tiveness of the existing sediment trapping dam in minimizing the
hydraulic transport rate of asbestos waste material into Pine
Canyon Creek. Because asbestos from natural and disturbed areas
is aireaay present in and will continue to enter the surface
water pathway, it is not possible to quantify a reduction in risk
that this remedy will achieve. However, it is believed that
minimizing the asbestos entering Pine Canyon Creek will decrease
the downstream human health risk due to both inhalation of
rtrurpcr.dsd asbestos fibers. Entry into the JM Mill Area OU is
controlled by locked gates. By restricting access to the JM Mill
Area OU, the generation of airborne asbestos emissions will be
minimized, reducing the risk from inhaling asbestos fibers for
persons in the immediate area.
The major features of the selected remedy are engineering con-
trols designed to reduce hydraulic transport of asbestos into lo-
cal drainages. These controls include: i) a cross canyon diver-
sion system; ii) a run-off management system; and iii) grading.
These engineering controls consist of the following components:
Cross Canyon Diversion System:
—Diversion ditch;
—Improvement to existing upslope diversion;
Run-off Management System:
—Improvement to existing sediment trapping dam;
—Reclamation of disturbed areas with native vegetation if
the revegetation pilot project is successful;
'\
Grading:
—Grading benches perpendicular to the slope;
—Consolidation of asbestos-containing site soils;
All diversion and drainage facilities shall be designed and con-
structed to accommodate the anticipated volume of precipitation
and peak flows from surface run-off in a 25-year, 24 hour storm.
All tailings piles shall be protected from 100-year peak stream
flows.
All containment structures shall be designed by a registered
civil engineer and construction shall be supervised and certified
by a registered civil engineer or certified engineering
geologist.
21
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A verification sampling plan ("VSP") will be instituted to con-
firm that an appropriate reauction in hydraulic transport rate of
asbestos is achieved. The VSP will include surface water model-
ing and surface water sampling as necessary.
Operation and maintenance activities will be required to ensure
the effectiveness of the stream diversions and sediment retention
structures. These activities will include: (1) inspection of
engineering systems to ensure integrity and performance, (2)
removal of sediments from retention dams, (3) any repair work
necessary to maintain the integrity of the remedial systems, and
(4) maintenance of the vegetation. EPA will review the remedial
actions ef fectiv^ricos pursuant to CZRCLA Section 121 (c) , -42
U.S.C. Section 9621(c).
The total capital cost for the selected alternative is estimated
at $1.1 million. Annual operation and maintenance activities are
estimated at SRis.ooo. The total present worth cost for the
selected alternative is estimated to be $1.9 million. Table 2
summarizes costs for the selected alternative.
During the remedial design and construction process that follows
this ROD, some changes to the selected remedy may be required and
will be made in accordance with CERCLA Section 117, 42 U.S.C.
Section 9617, and 40 C.F.R. Section 300.435.
11-0 DOCUMENTATION of SIGNIFICANT CHANGES
The selected alternative for the JM Mill Site is construction of
engineering systems to control the release of airborne and water-
borne asbestos from the JM Mill Area and accompanying measures,
as detailed in Section 10, above. At this time no significant
changes from the Proposed Plan have occurred.
12.0 STATUTORY DETERMINATIONS
Overall ^Protection of Hunan Health and the Environment
The selected remedy protects human health and the environment by
minimizing exposure to asbestos-contaminated materials. Proper
operation and maintenance practices will ensure the integrity of
the stream diversions, sediment trapping dams, vegetation and
fencing. Strict dust control procedures will be followed during
construction. Proper health and safety measures, including am-
bient air monitoring and personnel monitoring during implementa-
tion, will ensure that the health of on-site workers and the lo-
cal population is protected.
Cost-Effectiveness
The selected remedy is cost-effective in that it provides overall
effectiveness commensurate to its costs. The estimated costs of
the selected remedy are approximately one half the costs as-
sociated with a 15.24 centimeter (6 inch) vegetated cap
22
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TABLE 2
SUMMARY OF COSTS
PREFERRED ALTERNATIVE
Capital Cost O&M Present Worth Cost O&M
(per cubic meter) (per yr) (Present Worth)
$3.30 $27,000 $1,900,000 , $315,000 •
O&M = Operation and Maintenance
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(Alternative 6), and yet the selected remedy and Alternative 5
are similar in terms of'the level of public health and environ-
mental protection provided, except that construction of a
vegetated cap would involve a slightly greater exposure risk
during implementation.
Compliance with ARARs
The selected remedy will comply with all applicable or relevant
and appropriate requirements that have not been waived.
Utilization' of Permanent Solutions to the Maximum Extent Prac-
ticable
Currently there is no known permanent treatment or resource tech-
nology which would control release of asbestos from the soil at
the JM Mill Area OU. A thermal treatment alternative was iden-
tified, but it was eliminated from further consideration due to
difficulties associated with implementation and very high cost.
Of those alternatives that are protective of human health and the
environment, comply with ARARs and are cost effective, EPA has'
determined, and the State has concurred, that the selected remedy
provides the best balance of the various factors that CERCLA re-
quires be considered in remedy selection.
The JM Mill Area OU is located in a largely rural area, remote
from any population centers and just dovnslope from a large area
of serpentine which is a source of naturally occurring asbestos.
Off-site disposal of the mining and milling waste would be
prohibitively expensive and would have a significant short term
risk associated with transport of the asbestos to a landfill
licensed to accept asbestos waste.
Preference for Treatment as a Principal Element
Currently there is no proven, cost-effective treatment technology
that would permanently and significantly reduce the mobility,
toxicity or volume of asbestos at the JM Mill Site. Since no
cost-effective treatment alternative exists for this OU, treat-
ment was not selected as a remedy. Although several treatment
technologies were investigated during the feasibility study, it
was determined that no technology presently exists that would
result in a permanent and significant decrease in the toxicity,
mobility or volume of asbestos at the JM Mill Area OU in a cost
effective manner. Alternative 5 was found to be the best method
for addressing the threats posed by the JM Mill Area OU, taking
into account all of the statutory requirements and preferences.
23
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APPENDIX 1
REVIEW OF ASBESTOS ANALYTICAL METHODS
I. Asbestos Analytical Techniques
There are three conunonly accepted analytical techniques used to
measure asbestos. They are:
1) Phase Contrast Microscopy ("PCM"): An optical technique
useful in examining minute particles.
2) Polarized Light Microscopy ("PLM"): An optical tech-
nique that uses polarized light to identify minerals.
3) Transmission Electron Microscopy ("TEM"): A technique
using an electron microscope to achieve extremely high resolution
of asbestos fibers too small to be resolved using optical
methods.
A brief description, including the advantages and disadvantages
of each technique, is presented below.
A. Phase Contrast Microscopy
Phase contrast microscopy ("PCM") is a technique of optical
microscopy that is commonly used to analyze air samples collected
in the work place (e.g. in enclosed spaces). PCM translates dif-
ferences in the phase of light transmitted or reflected by the
object into differences of intensity in the image. The method is
better suited to analysis of work place air than ambient air be-
cause in the work place, asbestos accounts for a high fraction of
total particulates as opposed to in an environmental setting,
where the situation is normally reversed. Most of the available
medical studies of asbestos diseases have measured asbestos using
PCM. This is because PCM was the only technique available when
most of the occupational studies were done.
The PCM technique has three major limitations concerning its use
in the ambient environment: i) the method cannot detect fibers
with diameters of less than 0.2 micrometers. Many fibers in the
environment are much smaller than this; ii) PCM does not distin-
guish between asbestos fibers and other types of fibers. There-
fore, in the environment, the PCM fiber count may be completely
unrelated to the asbestos fiber content; and iii) PCM is also
very sensitive to the ratio of total particulates to fibrous
dust. In environmental samples this ratio is sufficiently high
that fibers may be effectively obscured so that PCM counts may
severely underestimate fiber concentrations.
For these reasons, it is widely accepted that the PCM method is
totally unsuitable for measurement of asbestos fibers in ambient
atmospheres.
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The major advantages of PCM are that it is a quick, cheap, well
established technique for measuring occupational levels of ex-
posure.
' • -,' .•'•• j> ••'•',- ; •'
B. Polarized Light Microscopy
Polarized Light Microscopy ("PLM") is the preferred technique for
analysis of bulk insulation samples. The PLM technique is rela-
tively inexpensive, quick (1/2 hour/sample) and allows: (1) iden-
tification all asbestos types, (2) distinguish between asbestos
and other fibrous and non-fibrous minerals and (3) identify most
non-asbestos components of samples. The resolution capacity of
PLM is 200x to 400x magnification.
There are two counting procedures that have been adopted for use
with PLM analysis, the point counting method and the field com-
parison or visual estimation method. The point counting method
uses a superimposed grid (graticule) with 100 points. The
operator counts the points where asbestos is present. The method
(point count) involves the preparation of eight slides, each of
which can be viewed at 100 possible points, to establish tae
presence or absence of asbestos at 50 points on each slide. The
result is recorded and reported as area percent based on the num-
ber of positive points. The following format is used for deter-
mination:
Area percent » a/n (100)
where:
a « number of points with asbestos fibers present
n - number of non-empty points counted.
The field comparison method, also called the 2-minute method,
with the.stereobinocular light microscope, is used to quantify a
large sample (e.g., l ounce) using the microscope at 30-40x.
The operator estimates the homogeneity of the mixture and es-
timates the percentage of each individual fibrous component.
The disadvantages associated with PLM include:
o Asbestos content determination is usually done by visual
estimate (field comparison) or point counting, and is
thus qualitative; concentration is expressed as the
ratio of asbestos to non-asbestos particles or percent
by area.
o Small fiber identification is difficult because certain
optical properties (birefringence and the angle of ex-
tinction) are hard to determine in small fibers.
o The thinnest fibers that can be observed are ap-
proximately 0.4 micrometers in diameter; fibers this
small, though observable, cannot usually be identified
for mineral type.
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o Highly skilled analysts are required, particularly in
view of the subjective nature of the determinations.
o The detection limit is 1 area percent.
Samples may still contain asbestos in quantities below
the PLM detection limit.
o A precise procedure for sample preparation has not been
developed. Therefore, PLM suffers from the variation
introduced during sample grinding and preparation. It
is very difficult to standardize the preparation of bulk
samples, especially soil samples.
Using PLM to identify asbestos in soils can be difficult because
soils are subjected to erosion and weathering; asbestos bundles
become separated and broken into smaller/ possibly sub-optical,
:»i«es much more quickly than fiber bundles in relatively undis-
turbed insulating materials. * Asbestos fibers may also be dis-
persed by wind and by seasonal flooding. Therefore, a sizeable
fraction of the asbestos fibers in soil could be below optical
resolution. On the other hand, PLM is the only method of measur-
ing asbestos with an EPA approved methodology for sampling and
analysis, even though this methodology is specifically for bulk
insulation samples. Therefore, it is the one analytical method
that can be controlled, to a limited extent, in a quality
assurance/quality control plan.
C. Transmission Electron Microscopy
Transmission electron microscopy ("TEM") is the most powerful
analytical technique available for measuring asbestos. TEM has
.been used for air, water, or soil analysis. It is the preferred
instrumental technique for measuring asbestos in ambient atmos-
phere since it incorporates the most powerful combinations of
identification methods. TEM analysis uses electron microscopy,
at magnifications of 10,000 to 50,000 times, to detect asbestos
structures as thin as 0.2 nanometers in diameter. This is suffi-
cient to identify the thinnest asbestos fibrils under most cir-
cumstances. Besides the transmission electron microscope, which
allows the operator to locate very small fibers, this technique
can also utilize two mineral identification tools. These are
Selected Area Electron Diffraction ("SAED") and Energy Dispersive
X-ray Analyser ("EDXA"). Using these tools, the operator can
identify the mineral type from a single point on the specimen.
The disadvantages associated with TEN include the following:
o No widely accepted TEM method is available for the
analysis of asbestos in soils, making it difficult to
correlate interlaboratory data. Sample preparation
methods are not standard among workers, making the
comparison of results between sites or laboratories
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very difficult or meaningless.
Analysis requires a minimum of 6 to 8 hours over 2 to 2
days. Highly skilled analysts, are required and large
differences in results can occur due to operator
variance. TEM analysis is extremely expensive, over 20
times the per sample cost of optical methods.
TEM analysis is performed on a much smaller sample than
PLM so that obtaining homogeneity during sample
preparation is more critical.
~. Typi rally, total structures are counted. Sample
preparation (i.e., grinding) destroys the structure size
distribution.
TEM sample preparation alters the soil matrix. This is sig-
nificant because the sample is dispersed into very fine particles
oerore it is put onto a filter for analysis. Since asbestos oc-
curs in clusters and bundles as well as fibers, the sample
preparation process (in the case of soil) can destroy the struc-
ture of those forms and produce a very large number of individual
fibers of small size. Although total fibers are counted as cart
of the TEM analysis, these results must be converted to weight
percent, using data on length, width, and density. This conver-
sion to mass is necessary due to the sample preparation grinding
process, which artificially increases the fiber count. How the
TEM weight percent compares with air emissions and risk tables
has not been standardized by government or industry. Therefore,
interpretation of soil data results relative to air samples
and/or risk charts is very difficult, at best.
II. Problems with Using Asbestos Data in Quantifying Risk
Although the role of asbestos as a cause of cancer is clear, the
ways in which fibers cause disease are not well understood, and
this has complicated efforts to measure asbestos successfully.
Asbestos researchers have not agreed upon which attributes of as-
bestos are important to measure to assess risk, including size
and shape of individual fibers, number of fibers, total mass of
fibers, inclusion of asbestos bundles, clusters, and matrix
debris in the fiber count, and asbestos mineralogical type. For
example, most researchers think that longer, thinner asbestos
fibers (those longer than 8 micrometers and thinner than 1.25
micrometers) are more carcinogenic, i.e., The "Stanton
Hypothesis*. However, other researchers question this approach,
suggesting that both long and short fibers may be biologically
active. In addition to fiber dimension, surface chemistry of the
asbestos fibers may play a role in causing disease. Further,
there is disagreement whether mineral type is a factor in disease
causation. Some would argue that chrysotile asbestos may par-
tially dissolve in weakly acidic environments, facilitating fiber
clearance from the lung. However, EPA policy is that all asbes-
tos mineral types are equally carcinogenic.
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5itS o?he? pa?ticSIJ£1Qn?i microsc°Pes' and may be agglomerated
rirther althSoh »J%** !' S° that th6y are masked Or hidden.
anlfSrfAai J K- A has attempted to standardize asbestos
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JOHNS-MANVILLE COALINGA ASBESTOS MILL AREA OPERABLE UNIT
RESPONSIVENESS SUMMARY
FOR THE
REMEDIAL INVESTIGATION/FEASIBILITY STUDY AND PROPOSED PLAN
UNITED STATES ENVIRONMENTAL PROTECTION AGENCY RESPONSE TO COM-
MENTS ON THE PROPOSED PLAN FOR THE JOHNS-MANVILLE COALINGA AS-
BESTOS MILL AREA OPERABLE UNIT OF THE JOHNS-MANVILLE COALINGA
ASBESTOS MILL SUPERFUND SITE
I. INTRODUCTION
The United States Environmental Protection Agency ("EPA") held
a public comment period from May 25, 1990 through June 25, 1990
on EPA's Remedial Investigation/Feasibility Study ("RI/FS") and
Proposed Plan for the asbestos contamination at the Johns-
Manville Coalinga Asbestos Mill Area operable Unit ("JM Mill
Area OUW) in Fresno County, California. The purpose of the
public comment period was to provide interested parties with
the opportunity to comment on the RI/FS and Proposed Plan. The
RI/FS, the Proposed Plan and the complete Administrative Record
were made available on May 25, 1990 at the Coalinga Public
Library, the designated information repository for the JM Mill
Site. By May 25, 1990, fact sheets containing EPA's Proposed
Plan had been mailed to all interested parties and notification
of the public comment period was published in Coalinga and Han-
ford area newspapers.
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 responsiveness summary provides a review and summary of
significant public comments on the RZ/FS and the Proposed Plan.
In addition to summarizing significant comments and questions,
the Responsiveness Summary presents EPA's responses to those
concerns.
OVER'
II. OVERVIEW OF THE RECORD OF DECISION
EPA's selected remedy is Alternative 5 in the Proposed Plan
with minor modifications which are described in Section 10.0 of
the Record of Decision ("ROD11). It includes engineering con-
trols designed to minimize the release of asbestos from the JM
Mill Area OO into Pine Canyon Creek and institutional controls
designed to minimize exposure of persons on or near the mill
area to airborne asbestos emissions. The selected remedy in-
cludes the following elements: i) grading; ii) cross canyon
stream diversion; iii) improvements to the existing sediment
trapping dam; iv) revegetation pilot project; v) access
restrictions; vi) deed restrictions; and vii) dismantling and
disposal of the mill building and associated debris.
Other alternatives fully analyzed in the FS included: 1) no
action; 2) road paving, deed restriction and mill dismantling;
3) access restrictions; 4) capping the asbestos in-place with
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either a .5 foot or a 2-foot soil covering; 5) removal of the
contaminated material to an approved, off-site landfill; and 6)
thermal treatment of the contaminated material.
III. SUMMARY OF SIGNIFICANT COMMENTS AND AGENCY RESPONSES
The following section summarizes the major comments and
responses received on EPA's Proposed Plan for the Johns-
Manville Coalinga Asbestos Mill Area OU. A detailed section of
comments and responses can be found in Section IV. If any con-
flicts or a'mbiguity appear between the two sections, follow
Section IV.
The only comments received on the JM Mill Area OU were sent
to EPA by two potentially responsible parties, the Santa Fe
Pacific Railroad Corporation (SFPRC) and Marmac Resource
Company/Mareco, and by the California Department of Health
Services.
Comments Bv Santa Fe Pacific Railroad Corporation
While SFPRC states that they approve of EPA's preferred al-
ternative, they had several comments concerning what they
believe are mistakes in the Proposed Plan Fact Sheet that EPA
issued to the public. For example, SFPRC believes that the
Ponding Basin is not part of this Superfund site and that the
Mill site does not significantly impact the California
Aqueduct. They also believe that the Remedial Investigation
was not properly summarized in the fact sheet. Because asbes-
tos from the Mill Area was transported to the Ponding Basin,
EPA can consider it part of the Superfund site. During heavy
flooding, asbestos from the Mill Area has been carried by
streams onto the Arroyo Pasajero Alluvial Fan.
SFPRC also claims that the JM Mill Site is not similar to
the Atlas Asbestos Site as stated in .the Proposed Plan. EPA
responds that although the two sites are different in size and
impact/ they are similar in that both contain asbestos ore and
tailings and abandoned mill facilities. The two site are lo-
cated in adjacent drainage basins about three miles apart.
SFPRC questioned why two sets of soil sampling data were
used in the Public Health Evaluation which determines the
health risk froa the asbestos. One set of data was collected
by EPA and the other was collected by SFPRC. EPA notes that
both sets of samples were collected and analyzed with EPA ap-
proved methods and were checked to ensure quality. The samples
were taken from different areas at different times which ac-
counts for some of the discrepancies between the two sets.
SFPRC requested that EPA clarify that stream diversions
would minimize the potential for releases of asbestos into lo-
cal creeks and that actual releases are not currently occur-
ring. EPA acknowledges that releases are not occurring
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presently because the last few years have been very dry. EPA's
selected remedy will protect local streams in the event of
heavy rainfall or seismic activity in the future.
SFPRC also made several comments regarding the watershed
modeling done by EPA and by SFPRC. They also commented on the
way that EPA measured asbestos in the California Aqueduct. EPA
believes that both watershed models are valid.
EPA notes that SFPRC's detailed comments on EPA's soil sam-
pling and'watershed modeling are not significant because EPA
would select the same remedy based on SFPRC's data alone.
Comments Bv Marmac Resource Companv/Mareco
Marmac's comments concern what they believe are mistakes in
the Feasibility Study. Most of these statements are taken from
the Site Description and History section of the Feasibility
Study. Because the comments are not relevant to selecting a
remedy for the site, EPA is not responding to those concerns at
this time.
Marmac requested that EPA clarify that metals are not con-
taminants of concern at the site and that serpentine, not as-
bestos, was found in the chromite ore that Marmac transported.
While EPA can confirm that metals are not contaminants of con-
cern at the site, EPA's analysis of the chromite ore
transported by Marmac did show asbestos in the ore.
Marmac prefers Alternative 3 in the Proposed Plan plus grad-
ing. EPA believes that Alternative 3 plus grading does not
adequately protect human health and the environment.
Comments By The State Of California
The State of California has concurred in the selected remedy
and has identified several California laws which it states are
applicable or relevant and appropriate. EPA has analyzed the
applicability and the relevance and appropriateness of applying
these lavs to the JM Mill Area OU in its response.
IV. PUBLIC COMMENTS RECEIVED AND AGENCY RESPONSES
This section includes EPA's response to significant public com-
ment* on the RI/FS and the Proposed Plan received during the
public comment period. The only public comments received were
letters from two potentially responsible parties (PRPs) and a
letter from the State of California.
The comments responded to herein have been summarized or
paraphrased as appropriate.
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A. COMMENTS BY SANTA FE PACIFIC RAILROAD CORPORATION ("SFPRC")
A.I Letter from Charles Robinson of Levine-Fricke, Inc., con-
sultants for SFPRC, dated June 25, 1990:
A.I. Comment: The Proposed Plan implies that the Ponding
Basin is part of the Site. The Ponding Basin is not part of
the Site. This is confirmed by the specific description of the
Site in numerous official documents either signed or approved
by EPA. For example, the Administrative Order on Consent
signed by EPA on November 16, 1987, contains the following
description:
The Site covers approximately 557 acres of land.... The
Site is located within the Pine Canyon Creek drainage basin....
The Site is located immediately adjacent to the New Idria For-
mation and ranges in elevation from 2,800 to 3,000 feet.
SFPRC requests that EPA clarify that the Ponding Basin is not
part cf the Site.
A.I. Response: CERCLA Section 101(9)(B) defines the tern
"facility" as "any site or area where a hazardous substance has
been deposited, stored, disposed of, or placed or otherwise
come to be located..." Contamination from the JM Mill Area OU
has been transported via surface streams to the Ponding Basin
of the California Aqueduct near Gale Avenue. Therefore, the
Ponding Basin can be included as part of the JM Mill Site be-
cause contamination from the Mill Area has come to be located
in the Ponding Basin. The "site" as defined in the Administra-
tive Order on Consent referred only to the area on which the
RI/FS was to be performed by SFPRC. This site definition did
not restrict EPA's discretion to address any other areas where
contaminant from the JM Mill Site has come to be located as
part of that site. It should be noted that EPA is not taking
any action in the Ponding Basin at this time and that the Pond-
ing Basin is not part of the operable unit addressed by this
ROD. N
A. 2. Comment! The Proposed Plan implies that the Site has
significantly impacted the Ponding Basin. This is not consis-
tent with the findings of the Remedial Investigation,
Feasibility Study, and Regional Report which EPA has con-
tributed to, reviewed, and approved. For example, EPA required
that SFPRC insert the following statement into the Feasibility
Study: (Page 4, Paragraph 4, 3rd sentence) "As previously men-
tioned, given the widespread occurrence of naturally occurring
asbestos in the vicinity, the potential additional health risk
from asbestos being transported off-site by wind and water is
extremely slight in absolute terms and negligible in comparison
to the health risks posed by naturally occurring sources."
Thus, EPA has determined that the Site's contribution to the
Ponding Basin is, at most, negligible. In addition, EPA should
explain in this discussion that the asbestos in the Ponding
-------
Dasin originated primarily from natural sources with minor con-
tributions from anthropic sources.
A. 2. Response; EPA's Proposed Plan for the JM Mill Area OU
states: "During heavy rains, asbestos can be transported from
the Mill Site down Pine Canyon Creek and eventually onto the
Arroyo Pasajero. During heavy flooding, asbestos-laden water
fills the ponding basin and can be released into the California
Aqueduct (see discussion on the Ponding Basin on page 7)." The
sediment trapping dam below the tailings pile at the JM Mill
Site has been breached at least once since 1980. This breach
occurred in 1983. EPA agrees that during dry conditions and
""inor rainfall events, the amount of asbestos transported into
Pine Canyon Creek from the JM Mill Area has been minimal.
EPA did not require that SFPRC insert the above-mentioned sen-
tence into the Feasibility Study. The language in this sen-
tence was written by SFPRC and included in a draft FS submitted
to £rA as required by the Consent Order. At a meeting between
EPA and SFPRC after the draft FS was submitted, EPA and SFPRC
agreed to edit the sentence as follows: "As previously men-
tioned, given the widespread occurrence of naturally occurring
asbestos in the vicinity, the potential additional health risk
from asbestos currently being transported off-site by wind and
water is extremely slight in absolute terms and is negligible
in comparison to the health risks posed by naturally occurring
sources." This latter sentence is what appears in the final,
EPA approved FS.
A.3. Comment; The Proposed Plan states that the Atlas Site is
"similar" to the JM Site. This is not true. Although both
sites contain asbestos, the Atlas Site is vastly larger than
the JM Mill Site, and contains vastly greater quantities of as-
bestos.
A.3. Response; The JM Mill Site is similar to the Atlas Mine
Site in terms of the presence of asbestos ore and asbestos mill
tailings at both sites and the presence of an abandoned mill
facility on both sites. The sites are located in adjacent
drainage basins approximately three miles apart. EPA agrees
that the Atlas Site is larger and contains a greater amount of
asbestos contamination. The similarities and differences be-
tween the two sites are described in the RIs for the sites.
A. 4. Comment: The description of the tailings pile in the
Proposed Plan should indicate that the concentration of asbes-
tos in the tailings piles (64%) is significantly less than that
in the naturally occurring asbestos-containing soils adjacent
to the Site (84%). This point is important to understanding a
unique characteristic of the Site: the Site is located within
an area of very high concentrations of naturally occurring as-
bestos.
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A.4. Response: jn the Site Background Section of the Proposed
Plan, page 2, paragraph !, EPA notes that: "The Mill site is
approximately one half mile below a 48 square mile area of ser-
pentine rock (Lhe New Idria Formation) that contains large
amounts of naturally occurring asbestos." EPA agrees that the
asbestos content of adjacent serpentinite soils is high.
However, the results of asbestos analytical techniques are sub-
ject to considerable uncertainty and the asbestos concentration
of serpentinite soils is highly variable. In addition, EPA's
investigation suggests that the tailings piles are ap-
proximately* three times as credible as the surrounding natural
areas. The evidence concerning the differences in asbestos
concentration of the tailings prl*» and the serpentinite soils
in the JM Mill Area are documented in the RI.
A.5. Comment: EPA's revised PHE uses EPA's soil sampling
results despite the limited value of this data. EPA's data
does not agree with oth«r sources in its reported asbestos con-
tent nor is it consistent witn SfPKC's approved data. bf^KC's
soil sampling data is sufficient for estimating potential risks
due to asbestos exposure. Therefore, EPA's data is inap-
propriate for use or consideration in the PHE for the Johns-
Manville Coalinga Asbestos Mill Site. Our letter to EPA dated
April 11, 1989, explains our concerns regarding EPA's data. In
response to our concerns, EPA's April 28 letter offers two
reasons for the use of its own soil sampling data.
The first reason given by EPA was that "[a] significant amount
of field work, sampling, and laboratory analyses were completed
by EPA prior to SFPRC's involvement in the Remedial
Investigation/Feasibility Study process."
This statement distorts the record. EPA first notified SFPRC's
predecessor, the Southern Pacific Land Company (SPLC), that
SPLC was a potentially responsible party for the Site in a let-
ter dated June 18, 1986. At that time, EPA advised SPLC of
EPA's. intention to complete the Remedial
Investigation/Feasibility Study for the Site. After meeting
with EPA, SPLC completed a soil sampling program and provided
EPA with a Draft Remedial Investigation report dated November
17, 1986. EPA did not begin its own soil sampling until the
summer of 1987, about eight months later. At approximately
that Mae time, SPLC submitted a Soil Sampling and Analyses
Plan to EPA, in response to EPA's comments that the Remedial
Investigation needed to evaluate the regional occurrence of as-
bestos. SPLC's additional soil sampling activities were con-
ducted in accordance with the Administrative Order on Consent
(Consent Order) executed by EPA and SPLC on November 16, 1987.
Thus, EPA's soil sampling program, and subsequent use of that
data in the PHE constitutes unnecessary and inappropriate
duplication of our sampling efforts.
EPA's second reason for using both sets of data was that all of
the data collected by both EPA and SFPRC are "appropriate" for
-------
use in the PHE without providing any justification. In par-
ticular, EPA offered no analyses, reasons, or data which
refuted the specific, factual SFPRC concerns regarding EPA's
data. We have documented our concerns with the methodology and
quality of EPA's asbestos analyses on numerous occasions. In
lieu of repeating those concerns here, please refer to our let-
ters to EPA dated May 19, 1988; June 10, 1988; August 11, 1988;
September 16, 1938; and February 27, 1989. Although EPA's
April 28, 1989, letter noted that its soil sampling data had
technical problems, EPA did not specifically respond to these
letters. Accordingly, EPA's second statement is not supported
by the. record. Please consider these letters (attached) resub-
mitted for the record.
Given the problems with EPA's data, and the fact that SFPRC
conducted an extensive regional soil sampling program under EPA
oversight in accordance with the Consent Order and approved by
EPA with no significant problems identified, we continue to
maintain that the PHE for the Johns-Manville Coalinga Asbestos
Mill Site should be based on SFPRC's data alone.
A. 5. Response; EPA's soil sampling for the Atlas Mine Sica
and the JM Mill Site was performed in 1987 between August 24
and October 9, prior to SPLC's signing of the Consent Order
that specified how SPLC would perform the RI/FS for the JM Mill
Site. SPLC's draft RI report dated November 17, 1986 had sig-
nificant technical problems and was not accepted by EPA. SPLC
subsequently signed the Consent Order on November 16, 1987.
EPA's PHE uses both EPA soil data and SFPRC soil data in cal-
culating cancer risk values. Both EPA and SFPRC samples were
collected and analyzed using an EPA approved sampling and
analysis plan. EPA and SFPRC data were validated using EPA
approved quality assurance/quality control plans. Dis-
crepancies between the two data sets do not justify discarding
either one. EPA has discretion to use any validated data that
was produced in the study of the JM Mill Area in the PHE,
before or after SFPRC signed the Consent Order to conduct an
RI/FS. In this case these data include both EPA and SFPRC
data. EPA deliberately separated out cancer risk calculations
using EPA and SFPRC data in the PHE, where possible, to address
SFPRC concerns that the cancer risk calculations in the PHE
using EPA data were not appropriate for the JM Mill Site. Even
considering the cancer risk derived from SFPRC data alone, EPA
has determined that the selected remedy is appropriate and
necessary to protect public health.
SFPRC'• detailed comments on EPA's soil sampling and
watershed modeling contained in its resubmitted letters are not
significant because EPA would select the same remedy based on
SFPRC's data alone. Asbestos is a known human carcinogen for
which no level of exposure is known to be safe. The asbestos
tailings at the Mill Area are more erodible than naturally oc-
curring asbestos outcrops. Significant uncertainty in asbestos
-------
soil sampling, watershed modeling and risk assessment also sup-
port EPA' s remedy selection. The selected remedy is consistent
with standard mining practices and applicable portions of
California's Porter-Cologne Act concerning mining wastes.
Nevertheless, EPA notes that EPA's and SFPRC's soil samples
were not split samples taken at the same time from the same
area, but rather were samples taken from different areas.
This, in combination with the difficulties with asbestos
analytical techniques, explains some of the discrepancy.
Both EPA's and SFPRC's watershed modeling reports used a range
of values for the asbestos content of tailings, mine surfaces
and surrounding soils. EPA's watershed model estimated that
the Atlas Mine Site contributes between five percent (5%) and
thirty six percent (36%) of the asbestos being deposited on the
Arroyo Pasajero alluvial fan. EPA's watershed model estimated
that the JM Mill Site contributes between two percent (2%) and
five percent (5%) of the asbestos being deposited on the Arroyo
Pasajero alluvial fan. SFPRC's watershed model estimated that
the Atlas Mine Site contributes 1.6% of the asbesros being
deposited on the Arroyo Pasajero alluvial fan. SFPRC's
watershed model estimates that the JM Mill Site contributes
0.3% of the asbestos being deposited on the Arroyo Pasajero al-
luvial fan. The PHE used data generated by both models to es-
timate risk from ingestion from of California Aqueduct water.
A. 6. Comment: As explained in the Regional Report and
Remedial Investigation, the SFPRC's data suggest separate 95%
confidence intervals for the mean asbestos concentrations of
materials and soils identified by our geological interpreta-
tions found in the region's asbestos source areas. This
demonstrates that Remedial Investigation and Regional Report
geologic interpretations and analytical results are valid and
useful for purposes of representing the region for the PHE.
A.6. Response: EPA agrees and has used these data, where ap-
propriate, in the PHE.
A.7. comment• The Proposed Plan should sake clear that the
stream diversion will minimize the potential for release of as-
bestos into local creeks. As written, the Proposed Plan infers
that asbestos is presently being released into local creeks.
Although a potential for such a release does exist, there is no
evidence that such releases are presently occurring.
A.7. Response; The selected remedy seeks to minimize future
releases of asbestos into Pine Canyon Creek in the event of
significant rainfall or other disturbance. Although releases
of asbestos from the Site into Pine Canyon Creek are not cur-
rently occurring because there has been very little rain in
this area for at least four years and the creek bed is dry,
releases of asbestos have occurred from the JM Mill Area OU in
the past. EPA must take into account past, present and future
8
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conditions at the JM Mill Site in its selection of an ap-
propriate remedy.
A.8. Comment: SFPRC'questions the validity of many assumptions
used in EPA'a watershed model. EPA's April 28, 1989, letter
noted that, "EPA views both [EPA's and SFPRC's watershed]
models as important inputs towards achieving the ultimate goal
of a reasonable and cost-effective remedy in the Atlas/Coalinga
area...both models were used in evaluating risks from both the
Atlas Site and the Johns-Manville Site." As we have stated
before, we'believe that EPA's watershed model has significant
problems. SFPRC discussed these problems at length in our let-
ter to EPA, dated September 16, 1988, to which EPA never
responded. This letter is attached for the purpose of resub-
mitting those comments.
EPA conducted additional modeling and included this modeling in
the Atlas Remedial Investigation. This modeling evaluated the
sensitivity of EPA's model to variations in asbestos content.
These evaluations indicated that this parameter appears to sig-
nificantly alter EPA's initial modeling results. We do not un-
derstand why this modeling has not conclusively demonstrated to
EPA the arbitrary and inaccurate nature of the earlier modeling
on which the PHE is, in part, based. EPA's April 28 letter
defends EPA's watershed model by noting that it is based on
conservative assumptions in order to protect health and the en-
vironment.
A. 8. Response; EPA's position on the validity and usefulness
of EPA's and SFPRC'S watershed model results, expressed in its
letter of April 28, 1990, has not changed. EPA's sensitivity
analysis was designed to measure the sensitivity of the model
to changes in the asbestos concentration of the serpentinite
soils. The results indicate that, as expected, the model is
sensitive to changes in soil asbestos concentrations. The dif-
ferences in results of EPA's and SFPRC's models are the result
of the different input parameters and different mathematical
approaches used. The discrepancy between the asbestos con-
centration in soils, tailings and asbestos ore as measured by
EPA and SFPRC can be attributed, in part, to difficulties with
asbestos analytical methods (see Appendix 1). Both data sets
were fully validated by EPA. EPA concludes in the PHE that:
"Considering the the major conceptual and mathematical dif-
ferences between the two (watershed) models, there is rela-
tively good agreement between them." All models are subject to
considerable uncertainty. Given that uncertainty, EPA has
determined that the selected remedy is appropriate and neces-
sary to protect public health. Because SFPRC's watershed
modeling results are sufficient to justify the remedy selected
by EPA, the comments contained in SFPRC's letter are not sig-
nificant.
A. 9. Comment: SFPRC defends SFPRC's watershed modeling
results: EPA's April 28 letter also states that many of the
-------
assumptions made in SFPRC's watershed model are subject to con-
siderable uncertainty. As an example, EPA states that SFPRC
assumed that "50% of the sediment delivered to the settling
basin is derived from channel entrenchment on the alluvial
fan." In fact, SFPRC did not make that assumption. As dis-
cussed in Chapter 3, Section 4.1, of SFPRC's Regional Report,
SFPRC reviewed published data from previous studies by the
California Department of Water Resources and the U.S. Bureau of
Land Management to -.estimate the origin of sediments being
deposited i-n the settling basin area. These data indicate that
37% to 62% of the sediments deposited in the Arroyo Pasajerc
settling basin originate from streambed and streambank erosion
of the entrenched Los Gatos Creek and Arroyo Pasajero channel.
SFPRC used that data to calculate a range of feasible estimates
in its watershed model.
SFPRC's watershed model consistently used conservative and
defendable input values to maximize the potential asbestos ero-
sion from the study area. In contrast to SFPRC's watershed
model, we have stated previously, we believe that EPA's
watershed model is not well documented and uses many techni-
cally indefensible input parameters.
A.9. Response; EPA has reviewed and approved SFPRC's
watershed modeling results. As noted above, EPA does not agree
with SFPRC's assessment of EPA's watershed modeling results.
The published data referred to in the above comment is subject
to the sane uncertainty as all other asbestos data (see Appen-
dix 1 of the ROD for a aore detailed discussion).
A.10. Commentt SFPRC does not completely understand nor agree
with EPA's methodology for calculating asbestos concentrations
in the Aqueduct. For at least two parameters, EPA's assump-
tions are not accurate. First, EPA's model assumed that the
natural serpentine soils contain 1% asbestos, whereas SFPRC's
laboratories actually measured asbestos concentrations of 85%
in samples of these soils. (See Comment 4-1 in our September
16, 1988, letter to EPA.) In addition, EPA used rainfall data
which substantially underestimated the precipitation intensity
duration expected in the vicinity of the Site. (See Comment
4.2 in our letter to EPA dated September 16, 1988.)
Consequently, EPA's original model assumptions underestimate
the amount of asbestos potentially eroded from the area of the
Atlas and Coalinga Sites. This effect is demonstrated in Table
6-8 of Draft PHE, which presents predicted asbestos concentra-
tions in the California Aqueduct, based on EPA's and SFPRC's
watershed models. EPA's model estimates that serpentine soils
contribute one million fibers per liter (MFL), whereas our
model estimates that this source contributes 38.2 MFL to the
Aqueduct. Similarly, EPA's model estimates that the entire
subbasin contributes 12 MFL to the Aqueduct, whereas our model
estimates that the subbasin contributes 39 MFL.
10
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A. 10. Response: in addition to problems with the accuracy and
precision of asbestos analytical methods for measuring 'soils,
the discrepancy between EPA's and SFPRC's results for asbestos
concentration in the '.- serpentinite . soils can be explained in
part as a result of sample variation. As noted in Response
A. 9, above, EPA has determined that for the purposes of the
PHE, there is relatively good agreement between the two
watershed models, despite the major conceptual and mathematical
differences between them.
A. 11. Comment: SFPRC disagrees with the Proposed Plan's sum-
mary of the Remedial Investigation results. The first sentence
->f t-be ««cond paragraph of the Proposed Plan's "Investigation
Results" section on page 3 reads as though that statement is a
fact: "High winds and driving vehicles over the area can cause
the asbestos to be released into the air." However, the state-
ment is not based upon scientific or factual data and is not a
conclusion reached by SFPRC in the Remedial
Investigation/Feasibility Study. Instead, this is a specula-
tive conclusion drawn by EPA. The statement should be
clarified to indicate that it is an estimate made by S?A, net
fact determined through the Remedial Investigation/ Feasibility
Study. EPA's description of the "protective crust" on the
tailings pile should indicate that EPA has estimated that winds
of sufficient force to cause airborne emissions of asbestos oc-
cur for only two hours per year.
A. 11. Response: The comment is confusing because it indicates
that the quoted statement contains an estimate, although it
plainly does not. Air dispersion modeling by the California
Department of Health Services found that disturbances of soil
by motorized vehicles and winds that exceed the threshold
velocity can cause airborne asbestos emissions. The Proposed
Plan does not specify that any particular period of time or
amount of asbestos may be released. The RI documents an es-
timate of two hours per year of wind sufficient to cause
visible emissions. In addition, vehicles do have access to the
JM Mill Site. Therefore, the statement in the Proposed Plan is
accurate.
A. 12. qpffiflient * Thermal destruction does not "chemically fix"
asbestos materials as indicated. A better description of this
process would be that thermal destruction "destroys1* or "fuses"
the asbestos. In the chart on page 4 of the Proposed Plan, the
name for Alternative 9 should be "Thermal Destruction" rather
than J»Vitrification."
A. 12. Response ; The ROD describes Alternative 9 as "Soil Fu-
sion Using Thermal Treatment". Alternative 9 would result in
the fusion of the asbestos tailings into a glass like sub-
stance.
A. 13. Comment: SFPRC supports EPA's selection of Alternative
5 as the preferred remedy and recommends its implementation
11
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without delay. SFPRC finds that the Proposed Plan contains a
number of inaccuracies which SFPRC recommends that EPA correct.
Attached to this letter is a copy of the Proposed Plan contain-
ing SFPRC 's handwritten suggested changes to implement these
recommendations.
A. 13. Response; The substance of SFPRC's comments on the
Proposed Plan are responded to in this document.
B. COMMENTS BY MARMAC RESOURCE COMPANY/MARECO ("MARMAC")
*
B.I Letter from Carla J. Feldman of Shield & Smith, counsel
for Marmac, d^t^d Jur.e 25, 199C.
»
B.I. Comment; The FS, at Chapter 1, page 2, section 1.3
states that Marmac transported "asbestos-containing chromite
ore11 to the Site. It should be noted that chromite ore does
not contain asbestos, rather, serpentine is typically found in
conjunction with chronite ore.
3.1. Response; The chromite ore mined in the New Idria Forma-
tion contains significant amounts of chrysotile asbestos be-
cause the serpentine matrix in which the chromite is found con-
tains high concentrations of that type of asbestos. EPA
analyzed samples of chromite ore transported from the JM Mill
Site to Marmac 's warehouse in the City of Coalinga and con-
firmed the presence of asbestos.
B.2. gQiMif n*; ; Marmac cites a number of statements in the FS
which they believe are inaccurate. These statements are sum-
marized as follows:
1) Marmac is believed to have excavated two retention
ponds in the eastern fork tailings pile to trap surface water
for use in Marmac 's milling operation.
2) Marmac discharged chromite tailings as a water slurry
to a series of additional settling ponds located on the
southern portion of the Site. After the solids settled out of
the water, the water was reused for processing more ore and the
ponds eventually became filled with chromite mill tailings.
3) Marmac is believed to have conducted milling opera-
tions at the Site for about two years.
4) Chromite ore was reportedly mined from a 5-acre por-
tion of the Site known as the Railroad Mine.
B.2. Response; None of the statements which Marmac disputes
are relevant to EPA's remedy selection. They appear in the
Site Description and History Section of the FS. Because these
statements are only potentially relevant to future disputes
concerning liability, EPA will not respond to Marmac 's objec-
tions to these statements at this time.
12
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B.3. Comment: Marmac requests confirmation in writing that
asbestos is the only chemical of concern at the JM Mill Site,
that metal concentrations are within the range of naturally oc-
curring soil concentrations and that the presence of metals
will not be considered a human health concern at the JM Mill
Site.
B.3. Response; EPA has determined that metals are not a con-
taminant of concern at the JM Mill Site and that the metals
present were within the range of naturally occurring soil con-
centrations. The PHE, which is appended to the RI, provides a
discussion of metals concentrations and their effect on human
health and the environment.
B.4. Comment ; Marmac comments that Alternative 3, with the
addition of grading to stabilize the tailings pile, would be as
protective as the preferred alternative and would cost less.
Therefore a modified Alternative 3 should be considered as the
selected remedy.
B.4. Response: EPA has determined that the selected rsnedy,
which utilizes a combination of stream diversions, sediment
trapping dams and grading, is the most cost effective way to
minimize the release of asbestos downstream of the JM Mill Area
via Pine Canyon Creek. Alternative 3 plus grading would not
mitigate the release of asbestos into Pine Canyon Creek because
the existing sediment trapping dam could be breached during a
heavy flood, leading to the transport of significant amounts of
asbestos. The fact that catastrophic floods do not occur often
in this area is not a rationale for ignoring the possibility
of such flooding. The existing sediment trapping dam has been
breached at least once since 1980 and very serious flooding oc-
curred in 1969. Therefore, Alternative 3 plus grading is not
protective of human health for people living downstream of the
JM Mill Area.
C. COMMENTS OF THE CALIFORNIA DEPARTMENT OF HEALTH SERVICES
("DOHS").
C.I Letter from Anthony J. Landis, chief of the Site Mitiga-
tion Unit, dated September 7, 1990.
C.I. qyManti DOHS stated that it concurs in the selected
remedy, and that the remedy contains "appropriate management
components to reduce asbestos releases from this site due to
erosion and man-made air emissions."
C.I. Response; EPA notes that the comment demonstrates state
acceptance of the remedy.
C.2. CftimftnV DOHS stated that several state lavs are con-
sidered by DOHS to be ARARS, including:
13
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California Air Resources Act
Health and Safety Code, Div. 26
Section 39000 et seq.
17 CCR, Part 3, Chapter 1
This state act has identified asbestos as a toxic air con-
taminant but has not established a state-wide ambient stan-
dard. However, the act has established an ambient air
quality standard for particulate matter which is enforced by
the Fresno County Air Pollution Control District. While it
is understood that EPA's permit exemption applies, the sub-
stantive requirements of this ambient requirement should be
met by cited federal ARARs.
C.2. Response! The Fresno County Air Pollution Control Dis-
trict has adopted PM 10 as a particulate natter standard for
Fresno County, pursuant to delegated authority under the
California Air Resources Act, Health and Safety Code Section
39000 et. seq. This standard is an ARAR for the Atlas Mine
Area Operable Unit. As noted in the DOHS ccinnent, this stan-
dard will be met by the same measures which will ensure that
the applicable federal NESHAPs for asbestos are met (i.e,,
misting measures during construction and access restrictions
and other controls after construction). The state's iden-
tification of asbestos as a toxic contaminant is not an ARAR
because, as recognized by DOHS, the state has not promulgated a
standard or level of control for this contaminant. EPA has
determined that compliance with the federal asbestos NESHAPs
found at 40 C.F.R. § 61.147 and 40 C.F.R. § 61.153 will provide
adequate protection of public health and the environment.
C.3. comment: in identifying ARARs to EPA, DOHS also cited
and stated the following:
Porter Cologne Water Quality Act
23 CCR, Chapter 3: Subchapter 15
Article 7 - Mining Waste Management
Section 2570-2574
This state act contains regulations establishing waste and
sittt classifications and wast* management requirements for
all mining waste. While included exemptions for liners and
leachate collection appear appropriate for this site, other
construction standards which require accommodation of 10-
year, 24-hour storm runoff controls in design criteria for
drainage and diversion structures as well as 100 year peak
stream flow protection for all waste piles are applicable
and relevant and appropriate for remedial action at these
sites.
C.3. Response; For existing units such as the JM Mill Area, a
determination of what requirements of Article 7 of the 23 CCR
should be complied with must be made on a case by case basis.
See Title 23, Section 2570. EPA agrees that the construction
14
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standard which requires accommodation of a 100 year peak stream
flow, found at Title 23, Section 2572(b), is an ARAR for this
operable unit. EPA also,agrees that the requirement of con-
struction standards which require accommodation of storm runoff
controls in design criteria for drainage and diversion struc-
tures are ARAR. However, after reviewing Article 7 and the
other Sections of Title 23 referenced therein, EPA has deter-.
mined that the correct ARAR requires that the construction
standards incorporate storm runoff controls designed to control
a 25-year, 24-hour storm event, not a 10-year, 24-hour storm
event. This is because the Atlas Mine Area Operable Unit is
classified as a Group A mining waste, not a Group B mining
waste. See Title 23, Section 2571(b)(l) and Section 2572(h)(l);
see also, Title 22, Section 66300 and Section 66310. There-
fore, EPA identified as an ARAR Title 23, Section 2572(h)(1)(A)
and Section 2572(h)(3). This latter Section incorporates by
reference Title 23, Section 2546(d) and («) , so the require-
ments of these two subsections are also ARAR. They deal with
measures required to ensure the adequacy of the precipitation
and drainage control systems.
C.4. Comment: In identifying ARARs to the EPA, DOHS also
cited and stated the following:
California Hazardous Waste Control Laws
Health 6 Safety Code, Div. 20, Chapter 6.5
Section. 25220-25241 et seq. and 22 CCR, Div. 4,
Chapter 30, Section 66001 «t seq.
These laws provide minimum standards for the determination
and management of hazardous waste. Most proposed actions on
site will meet the standards of these laws or will be ex-
empt. One aspect which continues to be applicable to and
recommended for these sites is the deed restriction and land
use constraints for permitted facilities. At a minimum, the
10 acres of privately held land at the Atlas site and the
entire Coalinga Mill site should be deed restricted as
detailed in the Health 4 Safety Code. Additionally, the
SARA amendments recognize the need for similar institutional
controls on federal lands. Therefore, it is further recom-
mended that the public lands with asbestos containing soils
and waste piles be deed restricted also.
C.4. Response: EPA agrees that the substantive portions of
California Health and Safety Code Section 25232 are an ARAR
for this operable unit. Any requirements related to notice,
hearing and other procedural mechanisms for implementing the
deed restrictions do not fall within the the definition of
an ARAR; however, the actual substantive restrictions con-
tained in Section 25232 (a) (1) and (2) are an ARAR. EPA has
determined that all of the private property at this operable
unit should be deed restricted to prohibit the uses
described in the California Health and Safety Code Section
25232(a)(1) and (2). EPA shall determine the appropriate
15
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manner for implementation of this requirement during the en-
forcement and implementation process for the remedial ac-
tion.
C.5 Comment; m identifying ARARs to EPA, DOHS also cited
and stated the following:
California Drinking Water and Toxic Enforcement Ac
Health and Safety Code, Div. 20, Chapter 6.6
Section 25249.5 et seq
Hazardous V\!
Information I
US EPA Regie
Philadelphia,
This act sets prohibitions on contaminated drinking
water with specific carcinogens and reproductive
toxins. Asbestos has been identified under this act
as a carcinogen. While insufficient design detail
exists at this time to determine if the discharge
prohibitions of this lav are applicable, the notice and
warning requirements are relevant. This notice and
warning requirement appears to be met by EPA's public
participation requirements and application of
requirements listed in 40 C.F.R. 61.156.
C.5. Response; The notice and warning requirements of -his
law would not be an ARAR because they are not substantive
standards or levels of control. See CERCLA Section 121(d),
96 U.S.C. § 9621(d). Furthermore, these requirements only
apply to a "person in the course of doing business" who
knowingly and intentionally exposes an individual to a
covered chemical. CH&S Code, § 25249.6. The operable unit
is an abandoned mill. No business is or will be operated
there; therefore, this lav does not apply.
Furthermore, the exemption in CH&S Code § 25249.10(c)
would be applicable to any releases expected to occur from
this operable unit.
While DOHS states that insufficient detail exits to
determine whether the waste discharge prohibition in Health
and Safety Code Chapter 6.6 apply, in fact this requirement
would not apply, for the reason that the prohibition only
applies to "people in the course of doing business." See
CH&S Code f 25249.5. As explained above, no one is or will
be doing business at this abandoned mill site.
EPA has also determined that no part of this law is
relevant and appropriate at this operable unit.
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