United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R02-86/037.
September! 986
SEP A
Superfund
Enforcement Decision Document:
Smuggler Mountain, CO
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TECHNICAL REPORT DATA
iPltau rtad Inttructiom on the rtverst btfort completing/
1. RIPOHTNO.
EPA/ROD/R08-86/005
3. RECIPIENTS ACCESSION NO.
4. TITLE ANO SUBTITLE
ENFORCEMENT DECISION"DOCUMENT
•Smuggler Mountain, CO
S. REPORT DATE
26. 19flfi
. PERFORMING ORGANIZATION CODE
7. AUTMORISl
a. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAMt ANO ADDRESS
10. PROGRAM ELEMENT1 NO.
1 CONTRACT/GRANT NO.
13. SPONSORING AGENCY NAME ANO AOORESS
U.S. Environmental Protection Agency
401 M Street, S.w.
Washington, D.C. 20460
13. TYP6 Of REPORT ANO PERIOD COve«E3
Pi na 1 POD
. SPONSORING AGENCY CODE
800/00
IS. SUPPLEMENTARY NOTES
16. ABSTRACT
The Smuggler Mountain site is located immediately northeast of the City of Aspen in
Pitkin County, CO. It comprises 110 acres of waste rock, tailings, and slag containing
high levels of lead and cadmium. The site is in close proximity of Aspen, CO which has
a year-round population of 4,500. In many cases, development in the Aspen area has
taken place directly over waste piles, or waste piles have been moved to the sides of
developed areas and remain as berms or mounds of contaminated soil. Portions of
contaminated soil have also been used for fill in some areas. The City of Aspen obtain
drinking water from surface waters in the area. The Roaring Forke River passes the sit
approximately 1,000 feet downgradient to the southwest, and is the nearest surface
water. The mining wastes which characterize the site are the result of years of
extensive mining, milling and smelting operations. As a result, wastes are highly
dispersed, and little is known about their disposition. Soil is the primary
contaminated medium; however, contaminants have been detected in some ground and surfac
waters.
The selected remedial action for the site is broken into two distinct operable
units. Operable Unit 1 - excavation and permanent onsite disposal of soils with lead
above 5,000 ppm, including a RCRA multi-layer cap; soil capping of all areas with lead
between 1,000 and 5,000 ppm lead; five-year ground water monitoring; and provision of a
(See Attached Sheet) ___^_
KEY WORDS ANO DOCUMENT ANALYSIS
DESCRIPTORS
b.lOENTIFlEffS'OPEN ENDED TERMS
COSATi Field Crou;
Enforcement Decision Document
Smuggler Mountain, CO
Contaminated Media: soil, gw
Key contaminants: heavy metals, lead,
cadmium, zinc
1«. DISTRIBUTION STATEMENT
19. SECURITY CLASS i Tins Rtporti
None
21. NO. OF PAGES
50
20. SECURITY CLASS iTIiu pagn
22. PRICE
EPA P«n» 2220-1 (*•». 4-77) »RKVIOUS COITION n o»»ou«Tt
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EPA/ROD/R08-86/005
Smuggler Mountain, CO
16. ABSTRACT (continued)
permanent alternate water supply for 5-7 residences. Operable Unit 2 - supplemental
RI/FS, with possible ground water remediation and mine reclamation activities.
Estimated capital cost of the remedy is $1,816,550 with annual O&M costs of $30,900.
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY £- 0 0 i, £ 4
'*## REGION VIII
ONE DENVER PLACE - 999 18TH STREET - SUITE 1300
DENVER, COLORADO 80202-2413
ENFORCEMENT DECISION DGCIMMT
REMEDIAL ALTERNATIVE SELECTION
SITE
Smuggler Mountain
Pi tic in Ccjnty, Colorado
DOCUMENTS REVIEKEl)
I am basing my decision primarily on the following documents describing
the analysis of the cost and effectiveness of remedial alternatives for the
Snuggler Mountain Site:
-Smuggler Mountain Remedial Investigation/Feasiblity Study
Fred C. Hart Associates, March 1986
-Smuggler Mountain Endangerment Assessment
Clement Associates, May 1986
-Smuggler Mountain. Focused Feasibility Study
Fred C. Hart Associates, July 1985
-Smuggler Mountain Addendum to Remedial Investigation/Feasibilty Study
Camp, Dresser and McKee, May 1986
-Hunter Creek Soils Investigations and Corrective Measure Recommendations
Engineering Science, 1985
-Final Technical Oversight Report, Activities 11/84 - 3/86, for the
Smuggler Mountain Site
Camp, Dresser and McKee, August, 1986
-Issues Abstract for Smuggler Mountain Enforcement Decision Document,
Clemmens, September 1986
DESCRIPTION OF SELECTED REMEDY
I have carefully reviewed and considered all the information, the
alternatives analysis, and the public comments pertaining to the selection of
a remedy for the Smuggler Mountain Site. Based on my review, I have
determined that the following actions at the Smuggler Mountain Site will
effectively mitigate and minimize damage to and provide acceptable protection
of the public health, welfare, and the environment. This determination is
made by the Regional Administrator of Region VIII consistent with the
delegation of authority for remedy selection dated May 6, 1986.
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The selected alternative is separated into two operable units. The first '
operable unit addresses the Smuggler site and does not include the reclamation
of the actual Smuggler Mine portion of the site. A second operable unit will
address the mine reclamation work and will consider ground- and surface-water
response actions if the results of ground water monitoring during the first
operable unit indicate that such actions are appropriate.
Operable Unit 1 - Site Remedy;
A. Source Isolation of High-Level Wastes.
Create an on-site repository on County-owned property to permanently
dispose of the high-level wastes (over 5,000 ppm lead) excavated from the
site. The repository will be under the perpetual care of a permanent
entity, Pitkin County, to assure the permanent disposition of the
contaminants. Consolidate all-high level wastes from the site (excluding
the mine site) In the repository. Cap the'repository with a multi-layer,
stable cap that meets RCRA performance standards for in-place closure
(40 CFR Part 264. Subpart N).
B. Source Isolation of Low-Level Wastes.
Isolate all low-level wastes (defined as areas with soil lead
concentrations of between 1,000 and 5,000 ppm lead) by capping in place
with 6-12 inches of clean topsoil and revegetating.
C. Increase Ground-Water Monitoring.
Monitor ground water quarterly on-site for a period of five (5) years to
determine efficacy of the caps in enhancing ground-water quality.
Quarterly reports to EPA will describe the results of monitoring and note
any trends observed. Monitoring results and reports will be used to
determine if further response actions are required.
0. Alternate Water Supply.
Provide a permanent, alternate, water supply by closing ground-water
wells for 5-7 residences and connecting the residences .to the existing
public water supply.
E. Operation and Maintenance of Low- and High-Level-Waste Caps.
Periodically.Inspect caps to note and repair any deterioration,
disturbance, or discontinuity to prevent cap failure. Weekly inspections
are anticipated during the first year. Bi-monthly inspections will take
place for the second year. After two years, Inspections will be
conducted monthly. From the beginning of the fourth year, quarterly
inspections will be conducted for the next twenty-six years.
Operable Unit 2 - Mine Reclamation and Possible Ground-Water Corrective Action;
A. Addendum to Remedial Investigation and Feasibility Study (RI/FS).
An addendum to the existing RI/FS will be prepared to characterize the
nature and extent of contamination and determine the appropriate extent
of remedy at the Smuggler-Durant Mine site. This addendum will be
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prepared in accordance with the National Contingency Plan. The Smuggler Mine
•RI/FSwill be subject to public comment prior to selection of a remedy.
B. Possible Ground-Water Corrective Action.
Current water quality data do not justify action, and ground-water
conditions are expected to improve after operable unit one is
implemented. However, ground-water monitoring results from the first
operable unit will be used to determine if ground-water response actions
need to be implemented. This determination will be made in a subsequent
decision document.
C. Performance of Remedy.
Perform remedy as approved by EPA in a subsequent decision document.
Such remedy will Include reclamation of the mine site and, if determined
to be necessary, ground-water corrective action.
DECLARATIONS
Consistent with the Comprehensive Environmental Response, Compensation,
and Liability Act of 1980 (CERCLA), 42 U.-S.C. section 9601 et seq., and the
National Contingency Plan (40 C.F.R. Part 300), I have determined" that the
selected remedy at Smuggler Mountain is cost-effective and consistent with a
permanent remedy that provides adequate protection of public health, welfare,
and the environment. I also have determined that the action being taken is a
8st-effective alternative when compared to the other remedial options
viewed. The State of Colorado has been consulted on the selected remedy.
e action will require future operation and maintenance activities to ensure
the continued effectiveness of the remedy. These activities will be
considered part of the approved action. EPA has not reached agreement with
the responsible parties at the site to implement the selected remedy.
Ground water quality will continue to be monitored on site. Subsequent
response action will be considered If the monitoring shows increasing
contamination.
The EPA or the potentially responsible parties for the Smuggler-Ourant
Mine area of the site will conduct an additional RI/FS to further characterize
the extent of contamination at that portion of the site, and will undertake
further response actions as determined to be necessary by EPA In a subsequent
decision document.
John G. Welles
Regional Administrator
Region VIII
TO HE SIGNED CN SEPTEMBER 29, 1986
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SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
A. SITE LOCATION AND DESCRIPTION
The Smuggler Mountain Site is located immediately northeast of the City of
Aspen in Pitkin County, Colorado. The location of the site is shown on
Figure 1. Beginning with the old Smuggler-Durant mine workings located.high
on the steep slope of the western side of Smuggler Mountain, the site grades
into the gentler slopes and terraces to the west-southwest towards the City.
Present site features are shown on Figure 2. Site elevation ranges from 7,930
to 8,160 feet above mean sea level. The site has been significantly altered
over the years by extensive commercial and residential development. Mine
wastes, such as waste rock, tailings, and slag, comprise much of the site.
The wastes occur either covered, uncovered, or mixed with native soil and
contain high levels of minerals containing lead and cadmium, among other
constituents. Through the Endangerment Assessment (EA) process, EPA has
established a site boundary based upon a 1,000 milligrams per kilogram (mg/kg)
or parts per million (ppm) soil-contamination level in soils and mine wastes.
This action level has been concurred upon by the Agency for Toxic Substances
and Disease Registry (ATSDR) in their letter to EPA Region VIII of
September 11, 1986. The State had recommended an action level of 500 ppm
lead, but such a level was determined-by ATSDK not to be appropriate.
Accordingly, the llu-acre site is defined by a 1,000 ppm lead isopleth which
is shown on Figure 3.
The site is in close proximity to the resort city of Aspen which has a year-
round population of 4,500. Consequently, the site is comprised of both
developed and undeveloped properties. In many cases, development has taken
place immediately on top of waste piles, o-r such piles have been moved to the
sides of developed areas and remain as berms or mounds of contaminated soil.
Portions of the contaminated soil have been excavated, used for fill, or
otherwise disturbed by grading, significantly altering the topography of the
site over the years.
The Roaring Fork River passes the site approximately 1,000 feet downgradient
to the southwest. Site drainage occurs largely as surface runoff with
channelization from mine discharge water (the Mollie Gibson Mine Shaft
discharges to the Roaring Fork River, and the Cowenhoven Tunnel discharges to
Hunter Creek). Drainage 1s also affected by two moderately sized basins:
Hunter Creek to the north; and the Salvation Irrigation ditch, which
transverses the site at an elevation of approximately 8,000 feet. The ground-
water system at the Smuggler site 1s complex and not clearly defined. Ground
water has been found to be present in both the sedimentary bedrock and in the
unconsolidated surficial deposits. Flow in the sedimentary bedrock is
characterized by secondary permeability, i.e., fractures and fault systems.
Current ground-water use in the area is limited to some private wells that tap
the alluvial aquifer of the Roaring Fork River Valley. The City of Aspen does
not use the alluvial aquifer but uses surface water from other sources.
Accordingly, the importance of the hydrology of the underlying sedimentary
strata is restricted to Its role in recharging the Roaring Fork alluvial
system.
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• . - • ' • L --•--•• - «
/ \ .,\ * N» ' ' \ '•
- "" >-—ix" *• '*•:*•*«',•* . *. .... ' » •
!^J*'*rf* *** ^^^^"^s:V^<" . ^""' ••••• X r» " '
• I' • \..*" ;\ ^;;^OX^A^ ^T " . •• * 'c««'*~*.
:•
-ttztw c vj-v.^ ifi'.Tr'-.'**/^^"
ASH/w **^/ c - *^' S» rI?7 t'-j.t-**^.' :i '
... ,'.-.''» -*•• •V^T^li*' '^!":"y-''^- -*S?EN O'ST
**•«
f
f
Figure 1
LOCATION MAP
•
SMUGGLER MOUNTAIN SITE
'MO C. MAAT AtaoClATCS. INC
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Hum or Cr.
Condominiums
ASPEN
Cowenhoven
Tunnel
Centennial
Condominiums
C
15
Mine
Mole Obson Mine
/
•oure*: COM 10*6
Sc«9«: 1" - 000"
Figure- 2 - Prfbcnt Site Kcalums
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sr/rv1
LEGEND
L«»t than 1000 ppm Pb
1000 ppm Pb Contour
3000 ppm Pb Contour
Mi 6000 ppm Pb Contour
Mi 10.000 ppm Pb Contour
\
Figure 3
r.:;i!:-'MTr.:
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6. SITE HISTORY.
The mining wastes which characterize the site are the results of years of
mining, milling, and smelting operations. Mining companies ran extensive
silver, lead, and zinc mining operations on-site in the late 1800's and early
1900's. Although several small operations started and ceased on the site
after 1930, records indicate that the bulk of the mining wastes at the site
were placed from 1880 to 1915 on the steep slope of the western side of
Smuggler Mountain near the Smuggler Mine shaft. In the mid-1960's, a
reprocessing facility was run at the site, causing the dispersion of the
wastes from the relatively distinct piles at the mine site to other locations
in the vicinity. The reprocessing also spawned a number of settling ponds
around the site. The wastes were dispersed further by subsequent residential
development.
From the time of the generation of the mining wastes to the present, the
materials have been strewn and dispersed over a wide area and at varying
depths from 1 or 2 feet to 40 feet. The relative toxlcity of the remnants of
the waste piles varies with the degree to which they are mixed with or covered
by other materials (native soil, topsoil, etc.). Since the waste piles have
been randomly dispersed, much of their disposition is unknown. The site is
underlain by relatively permeable strata. Ground water and, ultimately,
surface water may be affected by the percolation of precipitation through the
mineralized waste materials. •
A number of investigations have taken place at the site. Air quality, stream
sediment, surface- and ground-water quality and soil/tailings data were
collected in the vicinity of the Smuggler site by EPA and the Potentially
Responsible Parties (PRPs) from June 1982 through June 1966. Analyses of soil
and plant samples taken from the area in 1S82 indicated elevated levels of
trace metals (lead, cadmium) and called the site to the attention of local,
State, and Federal authorities. At the request of Pittcin County environmental
officials, the EPA Field Investigation Team (FIT) performed a sampling
investigation at the site in 1983. The Smuggler site was proposed for the
National Priorities List (NPL) in October 1984 and became final on the NPL in
May 1986. On several occasions during 1981-1983, news releases, meetings, and
other publicity issued by the Aspen Public Health Department advised local
residents against a) the use of garden soils suspected to be derived from
tailings and b) children playing in tailings (Dunlop 1986). Following
negotiations with the identified PRPs in early 1985, EPA approved the PKPs'
proposal to conduct the Remedial Investigation/Feasibility Study (RI/FS) with
EPA retaining an oversight role.
EPA issued three orders pertaining to the site during 1985. In June, EPA
issued a unilateral Administrative Order which names the property owners,
describes the site and potential hazards, and requires that EPA be notified of
and give approval for any movement of the soils or mining wastes in excess of
one cubic yard. An Administrative Order on Consent was negotiated and signed
by EPA and the PRPs in July 1985. This Order accepts the PRPs' RI/FS work
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plans and sets forth other legally binding agreements to govern various site
activities. EPA and the property owners also entered into a Consent Order in
August to undertake a limited emergency action on the site in which the
heavily contaminated area soutn of the mine and north of the tennis courts was
isolated by installing a fence to prevent access, and signs were erected to
warn the residents.
The final RI/FS was submitted to EPA in early 1986. EPA prepared an
endangerment assessement based on the RI in May 1986, and an addendum to the
RI/FS was prepared in June 1986. The data from these and other related
studies are summarized on Table 1 and Figure 4.
C. CURRENT SITE STATUS
The total quantity of contaminated materials at the site has been estimated at
approximately 410,000 cubic yards. The site 1s characterized by high
concentrations of lead, cadmium, and zinc, as well as elevated concentrations
of arsenic, barium, copper, manganese, silver, and mercury as found in
tailings and other mining wastes. Three different media were sampled by the
PRPs and EPA at the site to further define the extent of contamination. The
results of the sampling are:
Soil Sampling. Field activities have concentrated on determining the
extent of lead contamination. The initial site definition shown on
Figure 5 was adopted as a FIT starting point for investigation when the
site was proposed for the NPL in October 1934. The site definition was
based on data from preliminary soil leaa content values compiled by the
FIT investigation. The emphasis of subsequent surface sampling programs
conducted by the PRPs and EPA was to define the horizontal and vertical
distribution of lead in the soil. A perpendicular grid system with
400-foot sampling intervals was adopted to provide field reference for
sample locations, and soil sampling went as deep as 35 feet. The
sampling grid is illustrated in Figure 6. A summary of the soil sampling
activities 1s shown on Table 2. The initial FIT site definition was
refined by the PRP efforts which distinguished the site by using four
soil conditions, i.e., mine tailings, fill, man-made fill, and native
soil. Both mine tailings and man-made fill were considered to be
contaminated with lead at concentrations of over 1,000 ppm. Figure 7
illustrates the PRP site definition. The EPA contractor (Camp, Dresser &
McKee) collected additional soil samples, conducted soil analyses, and
defined the site In terms of the 1,000 ppm soil lead contour with the use
of geostatisties. The resulting contour map (Figure 8), which also shows
contours of higher levels of contamination, has been adopted as the site
definition nap by EPA and the PRPs;
e
Surface Water and Sediment Sampling. FIT conducted two surface water
sampling efforts in the vicinity of the Smuggler Mine site. The sampling
locations and the rationale for choosing them are shown on Table 3. A
summary of the results of the surface water sampling efforts are shown on
Table 4. Only barium, iron, manganese and zinc were detected in the
river. In addition, the levels of these constituents found in the river
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OVERVIEV OF insrcwc DATA OUJCTION jcnvrrtES
Location and Collector
Sanpllng
Period
No. of Samplers
or Samples
Reaarks
Air Quality/Meteorology
Site Vicinity, Ecology ft
Bnvinraent (PIT)
Mttin County Courthouse Roof ft
Site Vicinity, Colorado
Defartaamt of ftealth/Aspen/Mtkin
Bit. Haalth
Capitol Creek/Stnwaass
QiaiigHiiiii), Colorado DepartMent
of Health/Aspen/Fltkin Bnv. Health
Cttmd Ihter
Site Vicinity, Eoolf^y I
Bwircraoit (FIT)
Site Vicinity, Ecology ml
Bmriramt (ITT)
Uater
Site Vicinity, Ecology ft
Bnvinraontal (FIT)
Site Vicinity, U.S. Grakgical
Survey
ft-9/84
1982-84
1982-S3
9-11783
1960s-
present
7-hl-vols for 19 days, 120 sanples;
1 net station
2hi-vols
1 hi-vol
6 domestic veils (1 resanpled
11783)
4 veils (2 sanpled, 2 dry); 4
domestic veils re-sampled
7 sanples, qiolity only; sane
te-sanpling 11/83
Roaring Fork River above confluence
with tfcnter Creek; ilntcr Creek
above coiflucnce with Rnaring Fork
River
Air quality saaples analyzed for
TSP, particle siae, gastals
Lead; sporadic data anlayses; heavy
•etals aignificantly belov health
criteria
Background, lead
Elevated concentrations of Cd, Cu,
Zn
Data inconclusive; sailing of tvo
saturated wells continuing by REM
n
Generally good water quality; Pe
and Mi exceeded health criteria,
but not considered a problem
Flow and quality records; generally
very good water quality
Site Vicinity, REM H Te
(preliminary site characterization)
CPU l"Kf.
3/85
7 stations for lov-Qov water
quality
Data indicate
Iron site to
is
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, Table 1
OF HISTORIC
limed)
JTIflN ACTIVITIES
location and Collector
Sanpllng
Period
No. of Sanplers
or Sanples
Remarks
Sediment
Site Vicinity, Ecology i
Environment (FIT)
Site Vicinity, FDI U
(preliminary site characterization)
Soil/failings
Site Vicinity, Ecology I
Environment (FIT)
Site Vicinity, Aspen/Pitkin Bnv.
Health
Aspen Vicinity, Boon
•
Site Vicinity, Boon
9/83
3/85
9/83
1984(7)
1982
1983
fatter Creek Project, Engineering
Scic
1985
5 sites
5 sites
14 soil, 6 tailings
3 samples (1 coiposite)
11 garden samples
27 soil/tailing samples taken
throughput Centennial Development
project area
14 surface and subsurface
soil/tailing samples taken
throughout the Knter Creek
Candominim developnent
No aetals concentrations of note
identified based on veak acid
extraction analysis
Data indicate that contamination
from site to stream sediments in
site vicinity is negligible
4000-8000 pf* Pb reported in
soiytailings; 26-56 ppn Cd
Mine tailings materials near
Smuggler Trailer Court, 3000-21,000
ppn Pb
Soil lead values as high as 11,000
ppm, in upper horizons
AB-DPTA extraction; 40X of 25-acre
site (northern 1/3) determined not
to be Pb-ccn lamina ted; remaining
contaminated area reoonnendad to be
controlled by surface covering
Total lead values up to 5,790 ppm,
with an average of 1997 ppm; 9
samples exceeded 1000 ppm total
lead
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Air
Sediment
• Surface Water
o Ground Water
teurc*: COM 1BS0
Soil/Tailings
Figure 4
Overview of Data Collection Activities
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Fij'ure 5
Initial SiLiDtfiniLion
Source: !•: b E 1984
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SUUOOifll-OUNANf
cw
»<•!» IMIH
Figure 6
GRID SYSTEM SHOWING SURFACE
LOCATIONS
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Table 2
SUMMARY OF SOIL SA^PLING ACTIVITIES
SMUGGLER SITE: JULY-AUGUST 1985
Sampling Procedure
Surface sampling
Test pits
Test boring
Number of Samples Collected
34 soil samples collected
from each node of gridpoint
7 test pits
15 soil samples collected
1 borehole
2 soil samples collected
Depth
0-6 inches
10 feet (average)
sample collected
at each
lithologic unit
35 feet
Sample collected
for each unit
Source: Fred C. Hart
1985
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100 400 «00
DETAILED SOIL CONDITIONS, HEFIH TO •LATI«l-tc VOLUME III
Figure 7
MAP OF SURFACE SOIL CONDITIONS
AT THE SMUGGLER MOUNTAIN SITE
IDOES NOT SHOW SOU UNITS T«»tCALLV OHO EH 8fflO® ppm NANOCg
Fill
Mina Talllnf a
Manmada Fill A Mine
o Swrfaca Sampling L»«a«lena
SOURCE; Nl/rs Smugetor Mountain Site. F.C. Hart. 0/60.
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MMTf H ClWn
CONOOUMUUS
^ x
/ A'^'VrfP
.«,„«.// > ^m-t. *«
ru
si
Figure 8
Current Site Definition Mn
LEAD CONTAMINATION
Pb KRIGED ESTIMATES
it
MCISOI « MOT
i«n
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Table 3
AM) RATICWLE FOR SURFACE V/ffER COLLECTION SCM1GKS
Station
Designation
Locations
Rationale
Surface Uater Samples
SV-001
Bunter Creek above confluence with Roaring Fork
River
SV-002 Roaring Fork River below confluence with Hunter
Creek
Stf-003 Roaring Fork River above confluence vith Hunter
Creek
QoMenhoven IXmel Drainage prior to confliirnce vith
stom drainage
SV-OQ5 Hollie Gibson shaft drainage prior to confluence
vith Roaring fork River.
SU-006 Roaring Pork River above confluence of Nallie
Gibson shaft drainage
Evaluate Anter Creek water quality previous to
influence of Roaring Fork River.
Evaluate Roaring Fork vater quality after influence
of Creek and Smuggler Mountain site.
Evaluate Roaring Fork vater quality prior to
influence of Hunter Creek and after influence of
9mggler fountain site.
Evaluate Couenhoven Tunnel drainage prior to
discharge into stom vater collection system.
Evaluate Hollie Givson drainage prior to influence
of Roaring Fork River.
Evaluate vater quality of Roaring Pork River prior
to the influence of any Brining or Milling
operations from Saggier Mountain site.
Source: ON 1985.
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Table 4
Concentrations of Dissolved Metals
in Surface Water Samples
Dissolved Metals
Station
SMD1 (Anter Creek)
9MXB (Roaring Fork belov
Confluence vith Anter Creek)
9MD3 (Roaring Fork above
Confluence vith Anter Creek)
SMJOft (Cbuenhoven Discharge)
SV-005 (Mollie Gibson Discharge)
Lead
N>
N)
11'
2.711
N>
Cadndui
M)
N>
N)
N)
ID
Arsenic
N)
N)
M)
ro
M)
Zinc
N)
M)
N)
278
377
Mercury
M)
H)
N>
N)
M)
Bariw
N)
N)
39
41
41
tevnese
M)
17
38
1430
96
Iron
78
193
727
1800
150
SU-006 (Roaring Fork above
Confluence vith fellie Gibson)
M)
N>
N)
N)
29
327
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were within the compliance range for ambient iwater quality standards set
by the State and EPA. Stream sediment samples were also collected in the
vicinity of the site, the results of which are sunmarized on Table 5.
Based on available data and in consideration of the reducing conditions
of tailings piles, it was concluded that on-site contaminants were not
mobile enough to lead to a substantial increase in the levels of metals
in surface water and surface water sediments.
Ground Water Sampling. Seven existing private wells were sampled and
eight monitoring wells were installed to obtain ground water data.
Private wells PW-5 and PW-7 are considered to be down-gradient. EPA
installed four monitoring wells, two of which were dry. EPA subsequently
installed four more monitoring wells. EPA well GU-01 was established as
an upgradient well. tPA well GU-05 was established as downgradient, and
EPA wells GW-07, GW-08, GW-09, and GW-10 were established as on-site
wells. All ground water well locations (private and EPA) are shown on
Figure 9. The private wells were sampled by the EPA FIT in 1983, results
from those tests are shown on Table o. Ground-water samples were
collected from the six operational EPA monitoring wells in November 1985,
and February and May 1986. Results from the dissolved-metals analyses of
these samples are presented on Tables 7, 8, and 9. Water-quality trends
from these sampling data indicate that lead and arsenic are not present
as ground water contaminants. However, elevated levejs of cadmium were
noted at two private well sampling locations (Table 6) and at two EPA
monitoring well locations (Table 9).
Of particular importance to the selection of the recommended remedy was
the absence of lead in the well samples and the variable occurence of
cadmium in GW-07 near the Maximum Contaminant Level (f-'.CL) of .01 mg/1 as
established by EPA. In addition, levels of uranium and gross alpha were
found to be elevated in GW-07 and GW-G9. Zinc concentrations were also
found to be highest in PW-7. The .PRPs have postulated that despite the
abundance of calcium carbonate in the host rock, localized pockets of
mineralized materials could produce leaching conditions if derived from
the core of the mineralized zone. Using the results from the Focused
Feasibility Study and ground water monitoring, EPA has determined that
the potential ground water problem (as indicated by elevated levels of
cadmium, zinc, uranium, and gross alpha in GW-07 and GW-09) would most
likely be adequately addressed by the prevention of infiltration of
surface water through the tailings. Continued long-term monitoring of
the ground water was deemed necessary to evaluate the effects of the
remedy on the ground water quality.
Air Sampling. EPA took 115 samples of air particulute matter from a
background site and four on-site locations in 1985. A compilation of the
resulting data Is presented on Table 9. Analyses of these data revealed
that levels of arsenic, cadmium, lead and zinc in the air on-site were
elevated as compared to background, however, only cadmium and arsenic
were found to be present at levels above the proposed National
Environmental Standards for Hazardous Air Pollutants- (NESHAPS).
-------
RESULTS
«? in Kg/kg)
Ruaneter
AtadraM
Anthony
Arsenic
Bariui
Berylliw
CxftdiM
Calciui
GhrariiM
Cobalt
Copper
Iron
Lead
HngnesiiM
Manganese
Mercury
Nidcel
fotassiun
Seleniim
Silver
Sbdlui
IhalliuB
Tin
Vanadtm
Zinc
Station
3MJ01
(Bunter CreeK)
' 4,880
N)
1.9901
ND
M)
»,400,
16*
ND
15,600^
1,070
13,800.
4021
ND.
tv
ND
to
ND
3.2HJJ
NO2
ID
4501
SD-002
(Roaring Fork
Below Hunter Creek)
5,550
N)
ND
2,410*
ND
ND
19,800.
8l
ND
18.2001
1,950
' 11,000,
3361
ND.
ND1
ND
ND
ND
3'^
ND2
16
4621
SD-003
(Roaring Pork
Above Site)
3,810
ND
731
ND
ND
2,990
NT
ND
. 13,100*
18
1,680
2391
.22
Wr
714
2.1
ND
5,050.
ND2
ND.
321
9>-004
(Opportunistic Runoff Sanple)
11,400
ND
8.6
892*
ND
3
32,60^
12
21.6001
1,400
10,300.
609*
ND.
12
2,880
ND
ND
5,12^
UBTr*
f^J
1O
5381
Z Bstinted due to matrix interfere
Estimated - tnfetected.
ND: Not Detected.
Source: CTM 1905.
-------
••••i ,, <
l . x) / ( r""^.,..
1 ••••-./«« )
• I I \ v Vi *.\
;/ •*.w-Ji ).f. V
. o44>w-2~ / (.;ij453
* « \ C ^*»"'* »
•*l ' . Al^.S
*> ttu-f:'"^ i**fc*(.:V /
^vS^'^?V\:\ ^
•Ld*9 . • V •• -/ ij \
iftnSUX^ /3».m
i*/.;:•;'<.. •:vi<
fgc4.fi*.. \ih .\ •1.4-..
k.vV'«.x ^|"'V:^
fe.. TRC
>^
Figure 9
Oround-Wairr Well I.or;itJon.«
O FHT Sll«s Not Comptolwl •• W«H
O FIT W«bMotCofwi«!«dh SahratodZor*
• FIT W«Ne CompteMxl bt Saturated ?on«
A HEM I W«l«
@5 Priv.tS«9 Wells
-------
Table 6
RESULTS Of DISSOLVED fCTALS MIMESIS fOS HUVXTE HELLS
INCLUDED IN rir SAMPLING trron
„.-,.,
AluaUM
JWttaooy
Anaalc
•ariua
Miylliwi
CaifaluM
Calclu*
Oiroaliai
Cobalt
Cofuwr
Iran
tea*
NayMcltNi
•M^anaa*
MM cucy
NolybdanM
Mlckal »
OalanluM
011««r
Oodlw
DrUkia* Matac Standard
.,!_.-<•> •^-A.n, «b» M-l
•rKAOBBCy WfClNiWCy v^^A
MDUOI
•A*
SO MDISOI1
1,000 114
•A
10 MDtSI
MA
SO ' ROISI
MA
1,000 IS
100 12
MDUOI
HA
SO HDIS)
a MDio.s)
MA
•A
10 MDISOI
SO HOIS)
HA
»^2
•DUO)
MA
•DISOI
71
HA
NDIS)
HA
MDIS)
HA
NDISI
IIS
HDUOI
HA
I
RDIO.SI
HA
HA
•DISOI
mxsi
HA
PW-1
•QUO)
HA
•0(501
121
HA
NDIS)
HA
HDIS)
HA '
<
14
RDI10)
HA
HDIS >
RDIO.SI
HA
HA
ND(SO)
•01 S)
HA
..,,^
IW-4
HDUOI1
HA
•DISOI
79
MA
MDISI
HA
NDIS)
HA
HDIS)
29
HD(IO)
MA
MDIS)
RDIO.SI
HA
HA
NDISO)
•DISI
HA
Statle*
IW-S
19/011
•DUO)
RA
•DIM)
101
HA
13
HA
•DISI
RA
04
2349
•DUO)
HA
0
•DIO.S)
RA
HA
•01 SO)
HOIS)
HA
fW-S
Ill/OS)
•DUO)
RDI100)
RDISO)
SI
•0(10)
I
RA
HDIS)
HA
1C!
RDI10)
RDI10)
RA
9
HA
HA
•DUO)
HOI SO)
NDIS)
RA
FW-«
•DUO)
•A
ND(SO)
92
HA
NDIS)
HA
S
HA
HDIS)
RDI10)
•DUO)
HA
HDIS)
RDIO.S)
RA
RA
HDISO)
NDIS)
MA
-------
RESULTS OF DISSOLVED METALS ANALYSIS POX PRIVATE WELLS
INCLUDED IN riT SANTUNC EFFORT (cotlt.)
Varaaatar
ItMlllM
Ma
•MUdltai
time
DtUkUf Matac Standard Saapli**; Station
•tlaaiy'*1 Secondary •»-» 1**-* «*-J *»-« *»»-» lt«-S
|»/»J| Ill/Ml
NA HA HA NA A NA
NA NA NA . NA NA NA
NDI10} ND(IO) NDIIOI ND(IO) ND(1«) ND(10)
9.MO tS< Jl 462 717 2717 ZUi
n»-«
NA
NA
NDIIOI
42
Ml ramilta la ug/1 unlaca
Not taalyiad.
Ion balow aiaiaua datactloa Halt*.
ND: Hot dvtactad. tfitk datactioa limits •ko«n In par*nth«i»i.
Sowrc*: SU 1914.
li>t«rl» Drlntiin Matar ftaadarda (40 cm 141; 40 n StS6S, Dacaahar 24. 197S; Jkawndad by 41 Hi 2K02, July ». 1»1<; 4« m M641, Nova
l»7»f Cerractad by 49 r* 1S542. Narck 11. 1MO; 45 n S7142, August 27. 1»IO».
•
ty Drlnfctnq Matar Standards (40
-------
Table 7
GROUND MATER ANALYSES FOR NOVEMBER 1985
1
Parameter
Arsenic
Cadmi urn
Calcium
Iron
Lead
Magnesium
Manganese
Potassium
Sod1 urn
Zinc
GH-1
NO
NO
4.59
ND
NO
14.1
0.017
ND
20.5
0.062
GW-5
NO
0.004
136
ND
NO
23.3
NO
NO
9.69
0.060
Well
GW-7
ND
0.007
143
ND
NO
52.5
0.052
1.92
6.63
1.00
No.
GW-8
ND
ND
20
ND
NO
5.74
ND
ND
4.16
0.018
GW-9
ND
ND
119
ND
ND
38.5
NO
ND
ND
0.413
GW-10
ND
ND
128
ND
ND
36.8
0.043
NO
6.35
0.053
Notes:
Concentrations 1n mg/L; metals are dissolved.
Validation criteria qualifiers pertain to some data; details are Included
1n REM II files.
Source: COM 1986.
-------
Table 8
GROUND MATER ANALYSES FOR FEBRUARY 1986
Hell No.
Parameter
Arsenic
CadMiM
CaldUM
Iron
Lead
Magneslua
Manganese
PotasstiM
Sodlim
Zinc
Oil and Grease
TOC
Chloride
Sul fate
Bicarbonate
TOS
Radlim-226
Gross alpha
UranliM
Units
•9/1
•9/1
•9/1
•9/1
•9/1
•g/1
•9/1
•9/1
•9/1
•9/1
•9/1
•9/1
•9/1
•9/1
•9/1
•9/1
0C1/1
pCI/l
•9/1
GM-1
\
NO
NO
•46.5
0.034
NO
14.5
0.025
0.95
19.4
0.020
1.1
15
29
111
54
280
0.45 * 0.02
3*
0.0024
GM-5
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
Dry
CM- 7
NO
0.010
168
0.121
NO
53.9
0.226
2.*3
4.95
1.44
2.2
2.1
NO
215
180
905
0.45 * 0,02
140
0.310
GM-8
NO
NO
22.3
0.026
NO
6.2
0.05
ND
0.93
0.065
1.4
4.6
NO
30
49
95
0.21 * 0.01
4"
0.00021
GM-9
NO
NO
120
0.022
ND
41.2
NO
1.49
3.97
0.460
NO
4.9
ND
313
162
625 a
0.34 * 0.02*
120°* .
0.230*
GM-10
NO
NO
136
0.086
ND
39.5
0.174
1.64
6.19
0.066
NO
1.7
30
220
199
625
0.37 + 0.02
17 "
0.036
I
10
U>
I
Validation criteria qualifiers pertain to son* data and are Included In REM II files.
') Duplicate values:
RadlM-236 0.36 * 0.02
Gross Alpha 100
UranluM 0.210
Source: CON 19B6.
-------
.meter
•.dium
01
[40.]
25.u
10.u
[62.]
l.Ou
4.0u
47000.
4.0u
3.0u
[11]
[17]
5.0u
146000
[14.]
0.2u
S.Ou
[1030.]
7.9
3.0u
20600.
10.
17.u
2.0
87.
TABLE 9
GROUND WATER ANALYSES FOR METALS
MAY, 1986 SAMPLING
Ground Water Wells
05
[17.]
25.u
10.u
[81
1
4,
]
Ou
Ou
124000.
4.0u
3.0u
3.0u
[7.7]
S.Ou
21800.
[4.6]
0.2u
S.Ou
[1730.]
7.9
3.0
7920.
10.u
17.u
2.0u
48.
07
[36.]
25.u
10.u
[33.]
l.Ou
18.*
29500.
4.0u
3.0u
[5.5]
[72.]
25.u***
99SOO.
23
0.2u
S.Ou
[2190.]
25.u
3.0u
6210.
10.u
170.u**
2.0u
2510.
08
09
09
10
[29.]
25. u
10. u
[40.]
l.Ou
4.0u
192000.
4.0u
3.0u
3.0u
[25.]
S.Ou
5540.
[6.1]
0.2u
S.Ou
[602.]
S.Ou
3.0u
2250.]
10. u
17. u
2.0u
25.
[18.]
27.
10. u
[28.]
l.Ou
5.4
138000.
4.0u
3.0u
[5.2]
[9.8]
S.Ou
49200.
[3.5]
0.2u
S.Ou
[1760.]
5.0u
3.0u
5080.
10. u
170. u
2.0u
590.
17. u
25. u
10. u
[30.]
l.Ou
4.0u
137000.
4.0u
3.0u
3.0u
[5.8]
S.Ou
462000.
[4.7]
0.2u
8.0u
[1480.]
2.5u
3.0u
[4730.]
10. u
170. u
2.0u
596.
[28]
25»u
lU.u
[62.]
loOu
40Qu
131000.
4.0u
3.0u
3.0u
[3.2]
S.ilu
356000.
16
0.2u
8.0u
[1260.]
S.Ou
3eOU
5430.
lO.u
17. u
2.0u
35.
Result Is value greater than or equal to the Instrument detection limit but less than the
contract required detection limit.
Element was analyzed for but not detected. Detection limit is reported.
Exceeds Maximum Contawfntnt Level (Primary Drinking Water Standards)
Estimated due to split"recoveries outside limits.
Dilution Factor of 5
All values are expressed in micrograms per liter (ug/1)
Source: COM 1986
-------
OMCumiATicM; ct> »ruAW MLTQU.S AND PAnmcuiAna IN nie VICINITY
OF THE SHKXIttR MOUNTAIN SITU
Concentrations
total suspended parfclcu
Atsenlc
Cafeitai
lion
Lead
Manganese .
fine
NO.
Sailed
late* 66
37
37
31
31
37
37
Mean
43.J
0.0003
0.0012
i.4
O.l»
0.054
0.14
On site
MM1.U1
1*0
0.0071
7.J
0.01
0.22
0.54
tesplrable Slse Particulars
No.
S^.led
11
&i
JO
10
11
10
11
Mean
17
<0.0001
0.0014
0.50
0.10
0.02)
0.090
•
H*»U*«
4«
0.0009
0.0043
1.0
0.20
0.0(7
0.29
Background Concent rations
Iron SnouMSS
No.
Sailed
10 .
10
10
10
10
10
10
Mean
}f
<0.000l
0.0002
0.19
O.OS7
0.02C
0.07C
Hanlattai
160
0.0002
0.0011
3.5
0.10
0.091
0.36
Hail**
RteocMnunded Air
Concentrations
260* •
o.oooib
0.0004b
30C
1.S*
l.lc
3SC
\6O>A ftlmvy »lg
b»4M
-------
Investigations at the Smuggler site have established that the most important
potential routes of human exposure to the major contaminants, lead and
cadmium, at the Smuggler Mountain site are: the ingestion of contaminated
soil; inhalation of airborne particulates (dust); ingestion and inhalation of
household dust; ingestion of vegetables grown in contaminated soil; and
ingestion of contaminated ground water. The large extent of residential
development taking place at the site increases the potential for widespread
exposure. Lead and cadmium were chosen as the key contaminants at the site
based on the relative health and/or environmental risks. The Endangerment
Assessment (Clement and Associates, 1966) identifies studies for lead
contaminated environments that show blood lead levels of children increase
proportionately with soil lead concentrations and when soil lead
concentrations exceed 1,000 ppm, children's blood level concentration could
exceed 25 ug/1, a level above which toxic effects of lead poisioning have been
observed in children. The primary effect of lead exposure at toxic levels is
the inhibition of hemesynthesis in the biosynthesis of hemoglobin. Cadmium is
of concern for three reasons. First, it is reported in high concentrations in
tailings and soils throughout the site. Second, some forms of cadmium are
acutely toxic and potentially carcinogenic. Third, cadmium compounds are
generally more bioavailable than lead. Increased cadmium uptake normally
results in its accumulation-in tissues, particularly the kidneys and liver.
As levels of cadmium in tissues increase, dysfunction of the organs can
occur. The Endangerment Assessment enabled EPA to establish 10 ppir. as the
action level for cadmium at the site. Due to the relatively neutral pH of the
tailings host rock and the minerology of the ore deposit, metals in soils
on-site are relatively insoluble. Such insolubility of metals renders them
.slightly less available, but also increases their persistence in the
'environment.
As discussed earlier, the site boundary is defined by a 1,000 ppn, level of
lead contamination in soils and tailings. This decision was based on EPA's
sampling data indicating that the contaminated soils exceeded the action
levels of lead (1,000 ppm) and cadmium (10 ppm). The EA showed that lead and
cadmium levels in soil correlate quite well, i.e., that soil lead levels of
1,000 ppm would very likely be associated with a soil cadmium level of over 10
ppm. From this information, the recommended remedy was based upon the premise
that remediating soils heavily contaminated with lead would also adequately
address the high cadmium levels. Follow-up sampling is planned for the
remedial action phase which will determine compliance with the design clean-up
standards. EPA used the statistically based CDM/Geostat Systems map (Figure
5) as the basis for site definition and site remediation.
EPA has determined that the levels of lead and cadmium in the soils at the
site, in its present state, pose an imminent and substantial endangerment to
public health, welfare and the environment.
D. ENFORCEMENT ANALYSIS - See enforcement confidential attachment.
-------
£. ALTERNATIVES EVALUATION
The selection of the remedy to be performed at the Smuggler Mountain site is
governed by the requirement in 40 CFR Section 300.68(j) of the National
Contingency Plan (NCP) that the selected cost-effective remedy effectively
mitigate and/or minimize threats to and provide adequate protection of public
health, welfare and the environment. The remedy must also attain or exceed
all applicable or relevant and appropriate Federal public health and
environmental requirements identified for the site by EPA.
The threats at the Smuggler site that must be mitigated have been identified
by EPA as environmental exposure to heavy metals present in widely dispersed
mine wastes. Three primary exposure pathways have been identified:
1) the ingestion of soil or vegetables grown in contaminated soil; 2) inhalation
of contaminated soil particles or household dust; and 3) ingestion of
contaminated ground water. With respect to the first and second exposure
pathways, EPA has determined that direct ingestion or airborne exposure to all
soils with lead concentrations in excess of 1,000 ppm must be minimized so
that human health and the environment will be protected. Because of the
greater threat posed by soils with lead concentrations in excess of 5,000 ppm
lead, exposure must be eliminated entirely to the extent practicable. With
regard to the third pathway, EPA has determined that infiltration of surface
water to the aquifer system must be prevented or minimized for both the 1,000
and 5,000 ppm levels of contamination.0 The actions taken to mitigate releases
from the contaminated soils is also anticipated to inhibit the leaching and
the mobilization of contaminants into ground water. The elimination of the
three human pathways is the primary objective of the recommended remedial
action. The remedy is also expected to mitigate releases of cadmium and lead
to the environment.
In accordance with 40 CFR Section 300.68(j), six remedial alternatives were
developed to address the three contaminant pathways:
Al ternati ve Remedy
1 Increased Monitoring
2 Source Isolation
3 Replacement of Ground Water Supply
4 Plume Capture
5 Source Removal
6 EPA Alternative
7 No Action
These alternatives were developed using a two step procedure. First, in
accordance with 40 CFR Section 300.68(g), fourteen alternatives were evaluated
and screened for acceptable engineering practices, effectiveness and cost.
These alternatives, and the reasons for their being retained or dropped from
consideration are described below:
-------
1. Incineration. Contaminated soils often can be remediated by
excavation ana Incineration. The soils at the Smuggler Mountain site are
contaminated with toxic metals which are not affected or decomposed by
heat. Incineration would also release lead through exhaust gases into
the environment. Resulting fly ash may also be hazardous and would
necessitate regulated disposal. This alternative was eliminated because
of its lack of effectiveness as well as its potential deleterious
environmental effects.
2. Flood Control. As reported by Fred C. Hart Associates, in the RI/FS,
The Smuggler site is above the floodplain of the Roaring Fork River.
Flood control measures are not relevant or appropriate in development of
the remedial action.
3. Ground Water Barrier. Ground water barriers are often used to
physically contain contaminated ground water. Such a barrier at the
Smuggler site is not considered to be effective or practical since the
bedrock underlying the alluvium is fractured with secondary permeability,
and is replete with mine workings, rendering it unfit as the lower
confining level for the barrier. Consequently, vertical slurry walls
will not provide adequate protection. A ground water barrier is not
considered technically feasible or effective at the Smuggler site.
4. Soil Washing. This technology removes hazardous inorganics from
soils by flooding the site with a solution. The solution is then
collected and treated to remove the contaminants. This method was
examined for potential use at the Smuggler site. However, due to the
nature of the wastes and the low solubilities of the metal contaminants,
it was determined that soil washing would be ineffective at the Smuggler
site. In addition, soil washing could facilitate further dispersion of
the wastes on and off-site. Consequently, this alternative was
eliminated because of its lack of effectiveness as well as its potential
deleterious environmental effects.
5. Reprocessing of wastes. The wastes contain potentially valuable
quantities of lead, zinc and silver, so the option of reprocessing was
examined. Three technical constraints limit the option. They are:
a. nature of the wastes, i.e. mineralogy and concentrations;
b. adequate available land on-site to process the "ore" and
dispose of the tailings; and
c. technically feasible process to reduce the contaminants to a
level that 1s protective of public health and the environment.
In the case of Smuggler Mountain, all three of these constraints limit
the feasibility of this option. These "ores" are not rich by mining
standards and the mineralology is not well defined. Land is not readily
available for process buildings or tailings disposal. In addition,
although present mining technology may be able to reduce the levels of
-------
lead and zinc to levels much below the present values in the wastes (as
low as 500 ppm and 200 ppm respectively), these levels may still present
a health threat. Consequently, further processing or extra precautions
would have to be implemented to dispose of the reprocessing wastes to
protect public health and the environment. This option was eliminated
based on technical difficulties, cost considerations, and potential
environmental/public health concerns.
6. Surface Sealing. Surface sealing refers to covering the contaminated
areas with a physical barrier, such as soil, pavement, synthetic
materials or a combination of materials. It is used to minimize air and
water exposure pathways and was retained.
7. Grading. Grading is the general term used for reshaping the surface
of an area to minimize slopes so as to prevent soil erosion and to
control the flow of storm water. Grading provides stable sloped areas
for residential use as well as controlling erosion and storm water and
was retained.
8. Surface water diversion. There are three sources of surface water at
the site:drainage from nearby mine shafts; storm water originating
off-site and flowing onto the site; and rain falling directly on the
site. Surface water flow that is controlled would not erode surface
soils, but might contribute to some surface water percolating through
contaminated soils to ground water. Consideration of this technology in
the context of the Smuggler site would involve channelling the flow of
surface water entering onto, or originating on the site away from
contaminated areas. In addition, existing storm water channels, i.e.,
the Cowenhoven Tunnel Drainage, the Molly Gibson Ditch, and the Salvation
Ditch already control the flow of run-off by channels and diversion
berms. This alternative was retained.
9. Excavation and disposal. This would entail excavating contaminated
soils on the site and transporting them by truck to a RCRA-approved
facility for final disposal. Excavated areas would be backfilled with
uneontaminated soil and regraded to meet adjacent surface contours and
re vegetated. This alternative was retained.
10. Permeable treatment beds. Permeable treatment beds are constructed
by excavating a trench in the path of migrating contaminated ground water
and filling the trench with permeable materials which treat or remove the
contamination from the ground water passing through it. This alternative
was not eliminated at this time, but does not comprise any of the final
alternatives^
11. Subsurface collection drains. Subsurface collection drains are
gravel-filled trenches that intercept shallow ground water aquifers and
collect and transport the intercepted ground water to a holding area for
treatment. This alternative was not eliminated at this time, but does
not comprise any of the final alternatives.
-------
12. Replacement of water supplies. This technology would involve the
replacement of threatened or potentially threatened ground water supplies
with a water source that is not threatened by contamination, i.e., city
water supply. This alternative was retained.
13. Extraction and treatment of ground water. Ground water collected in
subsurface collection systems may need to be treated to remove metal
contaminants before discharge to surface or ground water. The treatment
facility would be located on-site. This alternative was not eliminated
at this time, but does not comprise any of the final alternatives.
14. Ground water monitoring. This technology Involves the design of a
ground water monitoring system that would follow the appropriate and
relevant RCRA standards (40 CFR Section 264.97). The purpose of the
monitoring system would be to detect any trends in ground water quality,
and to serve as an indicator for further action. This alternative was
retained.
After the preliminary screening, the second step in the development of
remedial alternatives was to use the eight technologies remaining to develop
the final six remedial alternatives. -The following alternatives include sonie
combinations of preliminarily screened alternatives and are described below:
Alternative 1. Increased monitoring
This alternative involves the collection of quarterly ground water
samples from four existing on-site ground water monitoring wells
installed in the alluvial aquifer by EPA (Alternative 14). Samples would
be analyzed for constituents associated with mine waste. Quarterly data
would be incorporated in an annual report and submitted to EPA. The
report would summarize data and evaluate possible trends. This
alternative was developed in accordance with 4U CFR Section
300.68(f)(1v). Because this alternative does not eliminate or mitigate
any of the major pathways of contamination, EPA has been determined that
Alternative 1 alone does not attain the applicable or appropriate and
relevant public health and environmental requirements, but may be an
integral component for verifying the efficacy of the final remedy.
Alternative 2. Source Isolation
This alternative combines three of the remedial alternatives mentioned
previously to Isolate the source of contamination from potential exposure
pathways (Alternatives 6, 7, and 8). It includes surface capping with
material of a certain reduced permeability, grading and surface water
diversion. The capping component would call for covering most
contaminated soils with Impervious material (e.g., buildings, streets,
paving, repository). The remaining areas would be covered with 6 inches
of clean topsoil and revegetated. The second component, grading, would
be used to minimize the slope of the capped soils to reduce erosion and
prepare areas for capping. The final component, surface water diversion,
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would entail the adoption of storm water diversion measures designed to
minimize contact of surface water with contaminated soils, and to reduce
infiltration and runoff to the extent feasible. In accordance with 40
CFR Section 300.68(f)(iii), by mitigating the current threat to public
health, this alternative attains all public health and environmental
requirements, although it does not prevent future threat from the
hazardous substances.
Alternative 3. Replace Hater Supply
This alternative involves the extension of the city water supply to
approximately five to seven additional residences (Alternative 12).
Water samples taken from existing ground water supply wells on the site
indicate that the Maximum Contaminant Level(MCL) of .01 mg/1 for cadmium
has been exceeded in one well (.018 mg/1). To prevent the threat of
violation of EPA Drinking Mater Standards, users of ground water possibly
impacted by the site would be permanently supplied with treated municipal
water from the City of Aspen. Pursuant to 40 CFR Section 300.68(f)(1v),
because this alternative does not eliminate or mitigate any of the major
pathways of contamination, EPA has been determined that it would not
attain public health and environmental requirements, but would reduce the
likelihood of present or future threats from hazardous substances in
ground water.
•
Alternative 4. Plume Capture
This alternative addresses only ground water contamination by using
subsurface collection drains and permeable treatment beds to treat the
contaminated plume and discharge the water (Alt. # 10, 11, 13). Pursuant
to 40 CFk Section 300.68(f)(ivl.this alternative does not eliminate or
mitigate any of the major pathways of contamination, EPA has
determined that it would not attain public health and environmental
requirements, but would reduce the likelihood of present or future
threats from hazardous substances in ground water.
Alternative 5. Source Removal
This alternative Involves the excavation and off-site disposal of all
contaminated soils with lead levels of over 1,000 ppb (Alternative 9) and
was developed in accordance with 40 CFR Section 300.68(f)(i) and (111).
The contaminated soils (approximately 410,000 cubic yards) would be
excavated, consolidated and transported by truck to an off-site
RCRA-approved land disposal facility. The excavated areas would then be
backfilled and vegetated. Pursuant to 40 CFR Section 300.6^(111). this
alternative exceeds public health and environmental requirements. -
Alternative 6. EPA Alternative
This alternative was developed by EPA and is a combination of several of
the alternatives developed by the PRPs (Alternatives 6, 7, 8, 12, and 14),
It involves: source Isolation of low level waste by in-place capping,
grading and surface water diversion; source Isolation of high level waste
by excavation and deposition in an on-site repository with an impermeable
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cap and surface water diversion; increased ground water monitoring
(quarterly); alternate water supply for population currently using ground
water; operation and maintenance of high and low-level waste caps; mine
reclamation and source isolation of wastes; and possible ground water
remedial action.
Alternative 7. No Action
In accordance with 40 CFR Section 300.68(f)(v), a no action alternative
was developed. Under this alternative, no action would take place at the
site. Ground water, surface soils, air contamination and surface water
would be left virtually unchanged. This alternative would allow the
continued exposure of the population to contaminated soils through direct
contact and through airborne dispersal and therefore, would not mitigate
or eliminate the threat to public health, welfare and the environment.
This alternative was eliminated from further consideration since an
unacceptable risk to public health and welfare remains.
Pursuant to 300.68(h) and (1). the remedial alternatives were screened and
evaluated for acceptable engineering practices, effectiveness and cost, and an
alternative is recommended. Table 11 presents a summary of the analysis and
evaluation of each alternative for technical and institutional constraints,
including costs, as established by the PRPs. Table 12 presents the critical
advantages and disadvantages of each alternative. Table 13 presents a summary
of the application of the seven proposed remedial alternatives to the
alternatives required to be developed by 40 CFR Section 300.68(f). The EPA
addendum to the PRP-sponsored RI/FS analyzed the cost estimates for each
alternative presented by the PRPs. Table 14 presents the capital operation
ana maintenance costs and present worth costs for each remedial action
alternative as adjusted by EPA. The present worth of annual operation and
maintenance costs were based on a thirty year period and on a discount rate of
seven percent.
The information on these tables was used by EPA to evaluate which
alternative or alternatives should be selected as the recommended remedial
action. In accordance with 300.68 (j), the selection of remedy is based on
how each alternative meets the specific response objectives of the Smuggler
site, and how cost-effective and feasible they are from both an engineering
and administrative perspective. EPA determined through the endangerment
assessment process that the critical remedial needs are: (1) the permanent
prevention of direct contact with and wind dispersal of highly contaminated
soils and (2) leachate management to restrict possible ground water pathways.
Table 15 summarizes the effectiveness of each proposed remedial alternative in
addressing the remedial response objectives. None of the alternatives alone
developed by the PRPs adequately address all of the response objectives
individually. Consequently, the EPA alternative (Alternative 6), a
combination of several of the PRPi alternatives, is the only alternative that
adequately addresses each response objective.
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Table 11
SUMMARY OF ANALYSES OF REMEDIAL ALTERNATIVES
FOR TECHNICAL Mil INSTITUTIONAL CONSTRAINTS
Alternatives
1: Increased Monitoring
2: Source Isolation
(Grading and surface
water diversion)
3: Replacement of
Water Supply
4: Plume Capture
(Permeable treatment
beds; or subsurface
collection and treat-
ment)
Technical and Institutional
Constraints
TECHNICAL: No constraints
INSTITUTIONAL: No
constraints
Public Healtn and
the Environme nt
TECHNICAL:
- Performance and real la-
bility are good
- Typical civil engineer
practices can be imple-
mented without problems.
- Safety concerns United
to typical construction
risks and to inhalation
of dust during
construction
INSTITUTIONAL;
• Seciiaent and erosion .
control plans
- Local building
regulations
- CERCLA requirements
TECHNICAL;
- Pertonaance and reli-
ability are very good
- Iinplementability is
relatively easy
- Safety concerns limited
to construction risks
INSTITUTIONAL:
- Building permits
- Municipal Water Supply
User Agreements
- CERCLA Requirements
TECHNICAL (Permeable Treat-
ment Beds);
- Lack of 'an Impermeable
bottom soil layer
adversely Impacts
performance and
reliability
This alternative Mould not
eliminate or reduce the
possibility of direct
contact with or wind
dispersal of contaminated
soil, nor would it reduce
the risk of groundwater
contamination.
This alternative prevents direct
contact with and wind
dispersal of contaminated
soils and nay reduce
groundwater pollution
pathways.
Oust produced during
construction is an adverse
but short-tenr, effect on
public health and the
environment.
Total Costs0
$ 129,064**
1,239,531
This alternative would not
eliminate or reduce tne
possibility of direct
contact with or wind
dispersal of contaminated
soil.
This alternative (replacing
water supply) prevents
exposure of the public to
the possible threat of
contaminated grounowater.
This alternative would not
eliminate or reduce the
threat of direct contact
with or wind dispersal of
contaminated soil.
IS,750
2,962.641
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Table 11 (Continued)
SUMKARY OF ANALYSES CF REMEDIAL ALTERNATIVES
FOR TECHNICAL AND INSTITUTIONAL CONSTRAINTS
Alternatives
4. (Cont)
5: Source Removal
6: EPA Alternative
Technical and Institutional
Constraints
- There 1s no operating
history
• Safety concerns limited
to construction risks
(especially open
trenches)
TECHNICAL (Collection and
Treatment);
- NO impermeable bottom
soil layer Impacts
performance and
reliability, adversely
INSTITUTIONAL (Permeable
Treatment Beds);
• Local building codes
- CERCLA requirements
- Surface water discharge
permits
TECHNICAL; •
• Excavation of all
contaminated soils would
require demolition of
on-site buildings
• Secure landfills have
reported some limited
leachate problems
(reliability)
• Disposal of 1.3 x 1C6 cy
would consume a
considerable volume of
secure landfill space;
capacity in a secure
landfill could become
scarce (Implementability)
- Safety concerns related
to construction
practices and the risk
of accidents during
transportation
INSTITUTIONAL:
• CEKLA rtqui rements
- ROM requirement!
• Sediment and erosion
control plans
'TJOiilCAL!
•'• Performance ft
reliability are good
-Safety concerns limited
to period of construction
• No constraints for
ground-water monitoring
INSTITUTIONAL:
- Sediment ft erosion
control plans
• Hater supply user
agreements
Public Health and
the Environment
This alternative provides, a
limited barrier to
migration of contaminated
groundwater
Dust from excavation of
contaminated and
uncontabinated soil would
have an adverse but short-
term effect on public
health and the environment.
Total Costs*
LONG-TERM;
- Prevents direct contact
with and wind dispersal
of contaminated soils and
eliminates potential
groundwater pollution
pathways at the site.
- Contaminated soil could
affect groundwater if the
secure landfill which the
waste is to be disposed
in generates leachate
which is allowed to
migrate off-site.
SHORT-TERM;
- Dusts froo contaminated
soil can be dispersed by
wind during construction
- Increase of accident ano
exposure risk during
transportation (see
safety, technical
constraints)
J66.730.QUO
*A$ estimated by PRP's
•*E«tiaat« ba>«d on 30 year*
•onftforiai with • 7t
discount r«e«.
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Table 12
u
CRITICAL ASSESSMENT OF REMEDIAL ALTERNATIVES
Alternative
1. Increased
Monitoring
Advantages
Inexpensive
Provides early warning If
potential ground-water
contamination were to migrate
off site
2. Source Isolation - Utilizes reliable, easy-to-
implement civil engineering
construction techniques to
effect remedy
- Protects public health and the
environment from on-site
contamination (dust and direct
contact)
• Reduces threat to ground water
by reducing the amount of
surface water allowed to
percolate through contaminated
soils
3. Replacement of
Hater Supplies
4. Plume Capture
5. Source Removal
6. EPA Alternative
Inexpensive
Municipal water supply systems
are safe and ea'sy to extend
Protects public health from
possibly contaminated ground
water
Alemative will reduce present
ground-water contamination
pathways
Permanently removes on-site
contamination and attendant
exposure pathways
Utilizes reliable, easy-to-
Impleoent civil engineering
construction techniques
Protects public health a
environment from on-site
contamination
Reduces risk to ground water by
reducing the amount of surface
.water allowed to percolate
through contaminated soils
Protects public health from
contaminated ground water
Provides early warning of
ground-water contamination
Soils with heaviest
contamination will be
completely and permanently
Isolated from surface
Disadvantages
Does not protect public healtn
and tne environment from
Oft-s1te contamination (oust
and direct contact)
Contamination may be released
from site as dust during
construction.
Existing groundwater
contamination pathways will
remain
Does not protect public health
and the environment from
on-site contamination (dust
and direct contact)
The bedrock under the site is
permeable, and ground water
may be able to flow below (and
by-pass) treatment beds or
subsurface collection drains
Does not protect public health
and the environment from
on-site contamination (dust
and direct contact)
Requires demolition of
existing homes and streets
Generates a significant amount
of hazardous waste to be
transported and disposed
Transportation 1s extensive
(70 million total travel miles)
Uses a significant portion of
RCRA-approved hazardous waste
landfill capacity
Groundwater contamination
pathways will remain, but
cover and Increased monitoring
are expected to reduce risks
Raises the need for
Institutional controls on low
level caps
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Table 13
APPLICATION OF PROPOSED REMEDIAL ALTERNATIVES
TO ALTERNATIVES REQUIRED TO BE DEVELOPED BY 40 CFR SECTION 300.68(f)
Remedial Alternative
Response Objectives
Off- Site
Disposal
Attain
Stds.
Exceed
Stds.
Alternative 1
Increased Monitoring
Alternative 2
Source Isolation
Reduce
Threat
No
Action
Alternative 3
Replace H20 Supply
**
Alternative 4
Plume Capture
**
Alternative 5
Source Removal
Alternative 6
EPA Alternative
Alternative 7
No Action
*This alternative does not include provisions for ground water
monitoring or replacement of water supply. Therefore, EPA is unable
to make the determination that such remedy will meet the applicable
or appropriate and relevant standards.
**This alternative would attain all SDUA standards, but would not
attain or exceed all public health and environmental standards at
the site.
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Table 14
EPA Estimate of
Total Capital and
Operation and Maintenance
Costs
Remedial Action Alternatives
Alternative
1
2
3
4
5
6
Description
Increased
Monitoring
Source
Isolation
Replace H20
Plume Capture
Source Removal
EPA Alternative
Capital Cost Annual 0 &
($) ($)
0 13,300
1,197,800 17,600
18,750 0
479,400 200,100
62,740,000 0
1,816,550 30,900
M Total Cost
(J)
131,964*
1,416.216
18,750
2,962,641
62,740,000
1,847,450
*Estimate based on 30 years monitoring at 3i discount rate
Source: CU-1 1986
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Table 15
APPLICATION OF PROPOSED REMEDIAL ALTERNATIVES
TO REMEDIAL RESPONSE OBJECTIVES "
Remedial Alternative Response Objectives
Air Surface Ground Water Permanence
Alternative 1 - - X
Increased Monitoring
Alternative 2 XX * **
Source Isolation
Alternative 3
Replace ^0 Supply
Alternative 4
Plume Capture
Alternative 5
Source Removal
Alternative 6
EPA Alternative
Alternative 7
No Action
^Ground water monitoring is not part of this alternative, therefore,
there 1s no guarantee of its effectiveness on mitigating any observed
ground Mater impacts.
**Permanence of this remedial alternative 1s contingent on institutional
controls. Both the high and low-level wastes may be subject to future
excavation, and exposure pathways may be reexposed.
***Permanence of this remedial alternative is contingent on institutional
controls. Although the low level waste material may be exposed during
excavation in the future, the high level wastes will be under the
perpetual care of Pitkin County and subject to a permanent land use
restriction.
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F. COMMUNITY RELATIONS
In accordance with the NCR at 40 C.F.R. Section 300.67, a community relations
plan was prepared by the REM II team member (ICF) and approved by the Region
VIII RPN and Community Relations Coordinator. As specified in the plan, press
releases and fact sheets were prepared and issued, and public meetings were
held when major events occurred, because Aspen, Colorado, is a well-known
international resort, special care was taken by the Agency to provide accurate
and timely information to the residents without unduly jeopardizing the
tourist industry.
Because of past efforts by the Aspen/Pitkin County Environmental-Health
Department, the community was already knowledgeable about potentially adverse
health effects from the mining wastes on the site. Consequently, most of the
effort was geared towards informing the public about the Superfund process and
the schedule which would lead to selection and implementation of the remedy.
Citizens and PRPs are very interested in cleaning up as soon as possilbe for
both public health and economic reasons. There is a smaller group of
individuals in the local mining business which wants to develop the mineral
resources in and near Aspen.
All the citizen comments were reviewed and considered prior to making the
final selection of remedy. The recommended remedy meets the Agency's
responsibility to protect public health, welfare, and the environment without
foreclosing the development of mineral resources in the area.
G. CONSISTENCY WITH OTHER ENVIRONMENTAL LAU'S
Section 300.68(j) of the National Contingency Plan requires that the lead
agency select a cost-effective remedy that effectively mitigates and minimizes
threats to and that provides adequate protection of public health, welfare and
the environment. This requires the selection of a remedy that attains or
exceeds applicable or relevant and appropriate Federal public health and
environmental requirements identified for each specific site. EPA has
determined that the following applicable or relevant and appropriate
requirements apply to the Smuggler Mountain site:
Applicable;
Safe Drinking Water Act; Maximum contaminant levels (KCLs).
Clean Water Act; Non-point source control; water quality standards.
Ground Water Protection Strategy: Protection and enhancement of Class II
aquifers.
Off-Site Policy
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Relevant and Appropriate:
Resource Conservation and Recovery Act (RCRA): Capping performance
requirements; ground water monitoring and corrective action; site access
restrictions; run-on, run-off controls; in-place closure of a landfill;
waste piles.
National Historic Preservation and Antiquities Act
National Environmental' Policy Act (NEPA); Requirements for preservation
of National Historic Sites (Smuggler Mine).
Safe Drinking Water Act (SDWA); Maximum contaminant level goals (MCLG)
In addition, the following requirements may be found to be relevant and
appropriate:
• State Statutes and Regulations on Water Supply Systems Additions.
• Colorado Mined Land Reclamation Act and Regulations.
- RCRA Guide to the Disposal of Chemically Stabilized and Solidified
Wastes.
- RCRA Guidance Manual on Closure and Post-Closure Interim Status
Standards.
In evaluating the alternatives, EPA has determined that the recommended
alternative would comply with these standards as follows:
Safe Drinking Water Act: Planned monitoring and subsequent remedial
action (if found to be necessary) for ground water contamination at the
site use MCLs as action levels. (EPA retains the option of considering
alternate contaminant levels (ACLs) when determining future action, if
necessary, to remediate groundwater contamination.)
Clean Water Act; Non-point source controls were considered early on In
the review of site characterization data, and In analysis of the low-flow
sampling of surface water and sediment. In 1983, the Field Investigation
Team determined that the MoIHe Gibson mine Drainage and the Cowenhoven
Tunnels are not permitted discharges. Surface water contamination is not
at this time a problem at the site. Consequently, non-point source
controls were not designed as part of the remedy. Additionally, surface
water quality standards of the Clean Water Act and State water quality
standards have not been exceeded in the site vicinity. However, if
continued ground water monitoring indicates elevated contamination,
action will be taken to assure the attainment of such surface water
standards.
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wi wt.uwc SiaflUdfUS .TOP
aquifer protection have been promulgated. Direct remediation of the
aquifer appears to be unnecessary at tnis tic.e since ground water
contamination.does not currently appear to present a serious risk to
public health or the environment. However, it in the future, ground
water is adversely impacted by contamination from the soils, RCRA ground
water protection standards as set forth in 40 CFR Section 264.92 shall be
considered to be applicable or relevant and appropriate at this site. In
addition, the proposed remedy includes provisions to place all private
well users (tapping the Roaring Fork alluvial aquifer) in the site
vicinity on city water.
RCRA; Surface run-on controls (40 CFR Section 264.25(c) have been
determined to be relevant and appropriate as part of the site remedy.
Since surface water run-on and leaching of contaminants to ground water
is a potential route for release of hazardous constituents at the site,
surface water monitoring and subsequent response action nay be
recommended if further ground water monitoring demonstrates increasing
contamination. EPA Monitoring Well Numbers 7, 9 and 10 are located on
the facility boundary as defined by RCRA. Ground water monitoring would
be implemented as Operable Unit number two of tne recommended remedy.
Capping requirements for landfills are being adopted for the high-level
waste repository. Data generated by EPA and the PKPs indicate that the
mine wastes to be placed in the repository are not highly susceptible to
leaching. The data show that the mine waste host rock is a carbonate
material and causes reducing conditions in the waste piles, thereby
rendering the hazardous substances in the waste materials more stable and
less mobile. Therefore, an impervious, multi-layer cap should be
sufficient to prevent leaching of hazardous substances from the
repository into ground water. RCRA standards for the in-place closure of
landfills or waste piles do not require liners and leachate collection
systems and are not consicered to be relevant and appropriate to this
situation. Periodic inspection and maintenance are appropriate (4U CFR
Section 264.303), as are post-closure care requirements (40 CFR Section
264.117). RCRA standards for disposal of chemically stabilized and
solidified waste would be relevant and appropriate only if plume capture
becomes necessary and the attendant water treatment facility on-site
produces sludge to be moved off-site.
H. RECOMMENDED ALTERNATIVE
Based on a comparison of the advantages and disadvantages of the five alter-
natives, EPA recommends that Alternative 6 be selected as the remedial action
alternative. The recommended action would, if properly and expeditiously
executed, accomplish a stable, low-maintenance, cost-effective remedy, and is
designed to mitigate or eliminate the toxicity and mobility of the
contaminants. ATI known existing sources and pathways of contamination would
be eliminated, thereby minimizing or eliminating risks to human health and the
environment. The Agency for Toxic Substances and Disease Registry (ATSDR), in
their memorandum of Septmeber 11, 1986, to EPA Region VIII, stated, "The
Smuggler Mountain Site represents a potential public health threat to area
residents. The EPA action level for lead HOuO ppm) is acceptable for future
remediation efforts." The chosen remedy is permanent to the extent
practicable and is separated into two operable units. The first operable unit
addresses the Smuggler site and does not include the portion of the site upon
which the Smuggler Mine is located. The second operable unit addresses the
Smuggler Mine. A detailed description of each operable unit follows:
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Operable Unit 1: Site Remedy
Operable unit 1 is separated into five components as follow:
A. Source Isolation of High-level Wastes. Isolate soils and tailings
with levels of lead at or above 5,000 ppn by excavation and removal to a
secure repository. This alternative could involve either the removal of
such material by shipping it to a RCRA certified facility, or by
depositing it in a secure repository on-site, as defined by EPA. EPA has
identified a suitable repository on the site, the County-owned Kollie
laibson Park. If the repository is chosen for deposition of the
high-level wastes, it will be excavated to the extent necessary to
accomodate the entire volume of high level waste on the site. It will
then be prepared to specifications set by EPA that adequately address the
issues of surface run-on and stability. All high-level wastes from the
site (other than the mine site, itself) will be consolidated and placed
in the repository. The repository will be graded and capped in
accordance with the appropriate and relevant RCRA standards for landfills
(cacped with a multi-layer cap possessing a permeability of at least
10*7). A drainage system will be designed according to EPA
specifications (designed to pass the 100-year runoff event with a minimum
of erosion). The repository will be under the perpetual care of a
permanent entity, Pitkin County, to assure the permanent disposition and
zero mobility of the contaminants.
B. Source Isolation of Low Level Wastes. Confine soils with levels of
lead below 1,000 ppm in such a manner that direct contact, surface water
erosion, and wind dispersal are precluded. This operable unit involves
the identification of the affected areas using the geostatistical
isopleth map. After identification and possible further sampling to more
clearly define the contaminated areas, the low level areas will either be
covered by six inches of topsoil, graded, and revegetated, or covered
with six inches clean fill plus six inches of topsoil and graded. Areas
needing further identification will be defined by additional sampling.
If such sampling is performed by the PRPs, EPA will verify such
sampling. Areas already remediated by property owners will be examined
by EPA to determine compliance with design standards.
C. Increased Ground Water Monitoring. Because the ground water system
in the area of the site is so uncertain* groundwater monitoring 1s
necessary to confirm the effectiveness of the remedy. Additional wells
will be installed as deemed necessary by EPA. A monitoring grid and
monitoring schedule will be established. Quarterly reports to EPA will
describe the results of monitoring and any trends observed. Ground water
in the vicinity of the site will be monitored for a period of five (5)
years quarterly to determine efficacy of the capping in enhancing ground
water quality. After the close of the monitoring period, the decision
must be made by EPA to either implement plume capture and treatment,
select alternate concentration limits, or take no further response action.
-------
D. Alternate Water Supply. This operable unit involves the
identification of domestic water wells immediately downgradient of the
site. After identification, such wells will be replaced by hook-ups to
the City water supply and will no longer serve as domestic-use wells.
E. Operation and Maintenance of Low and High Level Kaste Caps. The
purpose of cap inspections is to note and repair any deterioration,
disturbance, or discontinuity before it can impact cap integrity. Weekly
inspections are anticipated during the first year. Bi-monthly
inspections will take place for the .second year. After two years,
inspections will be conducted monthly, and from the beginning of the
fourth year, quarterly inspections will be conducted for the following
twenty-six years.
Operable Unit 2: Mine Reclamation and Ground Water Corrective Action
A. Mine Reclamation. The Smuggler-Durant Mine site will be remediated
separately from the remainder of the site. The current extent of
toxicity and mobility of the contamination at the mine site is unknown.
An addendum to the existing Remedial Investigation and Feasibility study
will be prepared to characterize the wastes and determine the appropriate
extent of remedy at the Smuggler-Durant Mine site in accordance with the
National Contingency Plan and in accordance with the applicable or
relevant and appropriate requirements necessary to mset Federal public
health and environmental requirements. The Smuggler Mine RI/FS will be
subject to public comment and a recommended remedy will be presented.
The appropriate extent of remedy, consistent with the NCR, would address
the possible historic value of the mine site. The plan for mine site
remediation, consistent with the goals and objectives of the RI/FS and
NCP, will be prepared by the owners of the mine site and submitted to EPA
for approval, or would be prepared by EPA. 'In accordance with the
requirements of the National Environmental Policy Act (KEPA), if the mine
site is declared a National Historic Site, the buildings and other
structures on the mine site would be adequately maintained for their
historic value. Applicable and relevant or appropriate standards and
requirements for the safety of workers and visitors to the mine site
would be complied with. At the same time, wastes on the mine site will
be treated or remedied so as to prevent and/or mitigate the present or
future threat of release in a manner that 1s protective of public health,
welfare and the environment. Such remedy would provide a level of
protection of public health and environment comparable to the remedy on
the remainder of the site.
B. Ground Water Corrective Action. If the results of ground water
monitoring conducted during the first operable unit indicate that
corrective action is necessary, alternatives will be developed to address
the situation and possible response actions will be considered.
C. Performance of Mine Reclamation and Ground Water Corrective Action as
Approved by EPA.
A conservative estimate of the total capital and operatidh and maintenance
costs for the recommended remedial alternative 1s 1.5 to 2 million dollars.
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OPERATION AKU MAINTENANCE
Oper&tion and maintenance at the site is separated into two components. The
first component addresses the cap for the high level repository, the second
component addresses the the low level waste cap. Both components are
described in detail in the preceding discussion on the recommended remedy.
Such maintenance includes monitoring of capped areas in accordance with a
schedule to be set forth by EPA to detect and remedy any erosion of the cap,
as well as land use restrictions imposed by Pitkin County on any subsequent
development of capped areas.
J. SCHEuuLE/FUTURE ACTIONS
4Q FY 1986
X
[Operable Unit
X * 1 Month
X + 2 months
X + 3 months
X + 6 months
X * 8 months
X + 9 months
X + 12 months
[Operable Unit
X + 1 month -
X •*•_ 3 months -
X + 6 months -
X + 7 months -
X + 9 months -
X •«• 12 months -
X + 20 months -
X + 60 months -
X ••• 62 months -
X + 66 months -
X + 72 months -
X + 80 months -
- Regional Administrator signs EDO.
• Resolution of enforcement activity
#1]*,**
- Provide alternate water supply
- Initiate site sampling/verification
- Initiate design of repository
- Complete design of repository
- Preparation of repository
- Excavation and deposition of highly-contaminated soils
- Capping of repository
- In *place capping of low-level soils
- verification of areas capped previously
- 26 years operation & maintanence of caps
f2]*
- RI/FS workplan complete
- Draft Rl/FS submitted to or prepared by EPA
- Final Rl/FS and recommended remedy
- Public comment
- Start design
- Complete design
- Start construction
- Complete construction
Review ground-water data, determine 1f future response is
necessary
Start design if necessary
Public comment
Complete design
Start construction
Complete construction
* All dates subject to restraints imposed by short construction
season in Aspen
** Grounawater monitoring continues quarterly since 4Q 1985
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LIST OF FIGURES
Figure Page
1 Location Map - Smuggler Mountain Site 2
2 Present Site Features 3
3 Lead Contamination Contours of Kriged Estimates 4
4 Overview of Data Collection Activities 9
5 Initial Site Definition Map (FIT) 10
6 Sampling Grid 11
7 PRP Site Definition Map 13
8 Current Site Definition Map 14
9 Ground Water Well Locations 19
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LIST OF TABLES
Table Page
1 Overview of Historic Data Collection Activities 7
2 Summary of Soil Sampling Activities 12
3 Surface Water Sampling Locations 15
' 4 Concentrations of Heavy Metals in Surface Water 16
5 Sediment Sampling Results 18
6 Ground Water Analyses of Private Wells 1983 20.
7 Ground Water Analyses - November 1985 22
8 Ground Water Analyses - February 1986 23
•
9 Ground Water Analyses - May 19ti6 24
10 Airborne Concentrations of Heavy Metals 25
11 Summary of Analyses of Remedial Action Alternatives 33
12 Critical- Assessment of Remedial Alternatives 35
13 Application of Alternatives to the Requirements of 300.68(f)... 36
14 EPA Estimate of Costs 37
15 Application of Remedial Alternatives to Response Objectives ... 38
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ERB SA^PLING/LAB NEEDS
OCTODEK 1986
Sampling Plans Anticipated
Site tome
Gary Western, CU
Walkerville, MT
Emergency Response
PI anned
Submission
4th Week Sept
2nd Week Oct
4th week Oct
PI anned
Sampling
3rd Week Oct
4th Week Oct
When needed
Comments
Submitted
Short Form
Generic QAPP
Sampling Planned
Site Name
Wasatch Chem, UT
Whitewood, SO
Montana Pole
PI anned
Sampl i ng
Retained
Retained
1st Week Oct
Sample
Type (number)
Dioxins/furans(25)
Metals (20)
Dioxin(20)
Comments
SAS
SAS
dependant on
Micronurtrients, UT 3rd Week Oct
Gary Western, CO 3rd Week Oct
Yttrium, CO November
Cd Pb soils (50)
split w/PRP
Hydrocarbon liq (15)
Radioactive soils(20)
funding
PRP SP Sub
Analysis TAT SP
SP submitted
dependent on
funding
SITE NAME
Data Validation
PRIORITY
COMMENT
Idaho Pole, CO 1st
Wasatch Chem, UT KS
Starr Ditch, CO KS
Leadville Drum, CO KS
Data need now critical
Priority Pollutants 4th week Sept
due 4th week Sept
due 2nd Week Oct
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