PB95-964408
EPA/ROD/R08-95/095
January 1995
EPA Superfund
Record of Decision:
Summitville Mine Superfund
Site (O.U. 0), Summitville, CO,
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ADMINISTRATIVE RECORD
INTERIM RECORD OF DECISION
FOR
WATER TREATMENT
Summitville Mine Superfund Site
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INTERIM RECORD OF DECISION
for
. WATER TREATMENT
Summitville Mine Superfund Site
Summitville, Colorado
DECLARATION FOR THE RECORD OF DECISION.
Site Name and Location'
Summitville Mine Superfund Site, Summitville, Rio Grande County, Colorado.
Statement of Basis and Purpose
This decision document presents the selected interim remedial action for point source water .
tteattnent at the Summitville Mine Superfund Site (Site) in Summitville, Colorado chosen in
accordance with the Comprehensive Environmental Response, Compensation and Liability Act
of 1980 (CERCLA), 42 U.S.C. ~ 9601 et seq., as amended by the Superfund AInendments and
Reauthorization Act of 1986 (SARA) and, to the extent practicable, the National Oil and
. Hazardous Substances Pollution Contingency Plan (NCP)( 40 CFR Part 300).
This decision is b~ed on the administrative record for this Site.
'.' . .
The State of Colorado Department of Public Health.md-the Envir<>nment (CDPHE) concurs ,with ,
the selected interim remedial action. '
Assessment of the Site
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Interim remedial actions are 'appropriate "to protect human health and the 'environment from an
imminent threat in the short term, while a final remedial solution is being developed. n ("Guide to
Developing Superfund No Action, Interim Action and Contingency Remedy RODs," EP A.
OSWER Publication 93SS.3-02FS-3, April 1991). Actual or threatened releases of hazardous
substances from this Site, if not addressed by implementing the interim remedial action selected
in this Interim Record of Decision (IROD), may present imminent and substantial endangerment
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. .
Description of Selected Remedy
.
This interim remedy addresses the treatment of acid mine drainage (AMD) and water conrn;n;ng
. . cyanide from the Summitville Site. The water originates from sources altered or disturbed
during mining activities at the Site. The selected alternative is feasible, implementable and cost .
effective in reducing or eHm;nating transport of acidity, dissolved metals, and metal/cyanide
complexes in the surface and ground water at the Site.
,
This interim remedial action is anticipated to produce continued reduction of contam;nated water
flows to the Alamosa Watershed. The resu1~ of the interim remedial action will be routinely
monitored to determine the additional actions needed at each portion of the Site to. achieve the
final, sitewide remediation goals.
The major components of the selected interim remedy are listed below.
~
Continued treatment of the French Drain waters in the Cropsy Water Treatment
Plant (CWTP); .
Destruction of cyanide in the water from the Heap Leach Pad (HLP) will continue
in the Cyanide Destruction Plant (CDP)/Metals Reduction Plan~ (MRP) until the
water quality meets remedial action objectives; .
Completion ofHLP remediation, followed by the conversion of the CDP to treat
. Acid Mine Drainage (AMD). The MRP would be closed and would remain on-
Site as a contingency facility; and . .
Containment of AMD during peak surface water flows that exceed CDP capacity
(500 gallons per. minute). The contained water would be treated before being
released into Wightman Fork during Interim Remedial Action.
.
.
.
This interim remedy is consistent with current or future activities to complete sitewide
remediation goals.
No changes have been made to the prefemd alternative originally presented in the Water
Treatment Proposed Plan. However, the .sequence of numbering the alternatives in the IROD
varies from that of the Water Treatment~S because some of the Water Treatment FFS
alternatives were not retained after the screening process. Therefore, Alternatives 2 through 5 of .
the IROD correSpond to AltemativeS 3 through 6 of the Water Treatment FFS, respectively.
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Statutory Declarations
,
This interim remedial action is protective of human health and the e:t;lvironment, complies with
federal and State applicable or relevant and appropriate requirements (ARARs) for this interim .
limited-scope action, and is cost effective. Although this interim action is not intended to
address fully the statutory mandate for permanence and treatment to the rilaximum. extent
practicable, this interim action does utilize treatment and thus is in furtherance of that statutory
mandate. Because this action does not constitute the final remedy for the Site, the statutory
preference for remedies that employ treatment that reduces toxicity, mobility, or volume as a
principal element, although partially addressed in this remedy, will be addressed in the final
response action. Subsequent actions are planned to fully address the threats posed by the
conditions at this Site. Because this remedy will result in hazardous substances remaining on-
, site above health-based levels, a review will be conducted to ensure that the interim remedy
continues to provide adequate protection of human health and the environment within five years
after commencement 9fthe reIP.edial action. Because this is an interim ROD, review of this Site
and of this remedy will be ongoing as the EP A continues to develop final remedial alternatives
for the Site.
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~ i~/1qtf
Dec,ember 15, 1994
William P. Yellowta
RegionalAdminis 'tor ,
U.S. Environmental Protection Agency, Region vm
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TABLE OF CONTENTS
DECISION SurvIlV1ARY ....................... . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1 Site Location and Description. . .. . . . . . . . . . .. . . . . . . ~ . . . . .. . . . . .. .. . . ~ . 1 '
1.1.1 Climate..... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.2 Topography... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.1.3 GeoIQgy....." . . .'. . . . . .. . . . . . . . . . . . . . . . . . ... . . . . . . . . . . . . . . . . 2
1.1.4 Hydrogeology '.............................................. 3
1.1.5 Present Surrounding Land Use and Populations. . . . . . . . . . . . . . . .'. . . .4
12 Site History and Enforcement Activities ......... . .. .. . .. . . . . . . .. . . . . . .. 4
12.1 Site History. . . . . . . . . . . . . . . .'. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
12.2 Enforcement Activities. . . . . . . . .. . . . . . . . . '. . . . . . . . . . . . . . . . . . . '. . . 6
1.3 Community Particip~on . . .. . . . . . .. . .. . . . .. .. . . . .. . . . . . . . . . . . .. . . . . .. 7
1.4 Scope and RQle of Interim Remedial Action within Site Strategy. . . . . . . . . . . . 8
1.4.1 Remedial Action Objectives and Goals .. # . . . : ~ . . . . . . . . . . . . . . . . . . 14
1.5 Site Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
1.5.1 Nature and Extent ofContaminarion . . . . . . . . . . . . . . . . . . . . . . . . .'. .. 15
1.52 Contaminant Transport and Migration. . . . . .. . .. . . . . . . . . . . .. . . . . .23
1.5.3 . ARARs[[[ 24
1.6 Snmmary of Site Risks ..........'.......................'........... 36
1.6.1 Screening Ecological Risk Assessment. . . . . . . . . . . . . . . . . . . . . . ... . . 37
. 1.62 Environmental Risk Assessment. .. .. .. . .. . . '.. . .. . .. . . .. . . .. .. . 38
, 1.6.3 Human Health Risk Assessment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
1. 7 Description of Alternatives. . . . . . . . . . . . . . . . . . . . . . . .. . . . . . .... . . . . . . . . 40.
1.7.1 Alternative #1' No Action. . . . . . . . . . . . . . . .. . . . . . . . . . . . . ..41
1.72 Alternative #2 Continue treatment of French Drain Sump and
. - CWP waterl Treat HLP water ............ '. . .41
1.7.3' Alternative #3" .' '.'Continue1reatIDentof'FrenebDrainS~pand., .,'
CWP waterl Treat HLP water/Convert CDP and
MRP to AMD treatment ffreat peak flow AMD in
MRP.. . . . . . . . . . . . . ~ . . . . . . . . . . . . . . . . . . . . . 42
Continue treatment of French Drain' Sump and
CWP waterl Treat HLP waterI Convert CDP to.
AMD treatment! Shut down ~I Use containment
for peak flow AMD control. ................ 42
Continue tIeatment of French Dt;ain Sump and
CWP waterl Treat HLP water! Construct new AMD
treatment plant IShut down the CDP, MRP, and
CW1"P .........................:....... 43
1.8 Comparative Analysis of Alternatives. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
1.8.1 Criteria 1: Overall Protection of Human Health and the Environment
. . . . . . . ... . . . . . . . . . . . . . '. . . . . . . . . . . ,. . . . . . . . . . . . 43
Compliance with ARARs ."............. .. . . .. .. . 44
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1.8.3 Criteria 3: Long-term Effectiveness and Permanence. . . . . . . . . . . . 45
1.8.4 Criteria 4: .Reduction of Toxicity, Mob~ty,.and Volume through
TreatInent . . . . . . . . .'. . . . . .'. . . . . . . . . . . . . . . . . . . . . .' 46
1.8.5 Criteria 5: Short-term Effectiveness. . . . . . . . . . . . . . . . .. . . . . . . .47
1.8.6 Criteria 6: Implementability. . . . . . . . . '. ~ . . . . . 0 . .. . . . . . . . . . . . 48
1.8. 7 Cri~a 7: Cost. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 49
1.8.8 Criteria 8: State Acceptance. . . . . . . . . . . . . . . . . . . . . . . . . . . 0 . . . 52
1.8.9 Criteria 9: Community Acceptance.. . . . . . . . . . ~ . . . . . . ; . . . . . . . . 52
1.9 The Selected Alternative. '. . . . . . . . . . . . . . . . . . . . . . . . . . . '. . . . . . . . . . . . . . . 53
1.10 Statutory Determinations. . ~ . . . . . . . . . . . . '. . . , . . . . . . . '. . . . . . . . . . . . ~ . . '. . 54
1.10.1 Protection of Human Health and the Environment. . . . . . . . . . . . . . . . . 55
1.10.2 Compliance With ARARs .................................... S5
1.1'0.3 Cost Effectiveness.......................................... 55
1.10.4 Utilization ofPennanent Solutions and Alternative Treatment
Technologies- or Resource Recovery Technologies to the Maximum Extent
Practicable~) """"""""'."""""""""""'" 55 .
1.10.5 Preference for Treatment as a Principal Element. . . . . . . . . . . . . . . . . . . 56
,.
2.0
RESPONSIVENESS S~Y . . . . . . . . . . . . . . . . . . . ~ . . . . . . . . . . . . . .'. . . . . . . 57
. 2.1 Responsiveness Summary Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57
. 2.2 Response to Water Treatment Specific Comments. . . ; . . . . . . . . . . . . . . . . . . . 58
. 2.2.1 Summary and Response to Local and Community Concerns.... .....58
2.2.3 Comprehensive Respo~e to Specific Legal and Technical'Questions .. 79,
Summary and Response to General Comments. . . . . . . . . . . . . . . . . . . . . . . . . 105
Summary and Response to ARARs Comments. . . . . . . . . . . . . . . . .- . . . . . . . . 120
Summary and Response to Reynolds and Chandler Adit Questions. . . . . . . . . 125
2.3
2.4
2.5
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REFEREN'CES .................... ~ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .'. . 133
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LIST OF TABLES
Table 1 -
Copper Content - Site Contaminated Water
Table 2 - .
Cyanide Content - Site Contaminated Water
Table 3a -
Site Surface Water and Treatment Plant Flow Rates
Table 31T-.
Site Surface Water and Treatment Plant Water Volume
Table 4-
Containment Content During High and Low Flow Periods
Table 5 -
Copper Concentration.at W.F. 5.5
Table 6 -
Total Cyanide Concentration at W.F. 5.s
Table 7 -
MARs
Table 8 -
Numeric Surface Water Q1.1a:lity Goals and MARs
Table 9 - .
Evaluation of Alternatives
Table 10 -
Cost Estimates for Alternative #1
Table 11 -
Cost Estimates for Alternative #2
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Table 12 -
Cost Estimates for Alternative #3
Table 13 -
Cost Estimates for Alternative #4
Table 14 -
Cost Esrim~te'3 for Alternative #S
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Figure 1 -
Figure 2 - .
Figure 3 -
Figure 4 -
Figure 5-
LIST OF FIGURES
Area Map
Mine Site Foo1print
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Geology - Cropsy Valley Section
Contaminflted Surface Water Streams
Alamosa River Stream Segment Classifications
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1.0
DECISION SUMMARY
. 1.1
Site Location and Description
The Summitville Mine Superfund Site is located about 25 miles south of Del Norte, Colorado, in
Rio Grande County (Figure 1). It is located within the San Juan Mountain Range of the Rocky
Mountains, approximately two miles east of the Continental Divide, at an average altitude of
. 11,500 feet. The 1,231 acre mine permitted area is positioned on the northeastern flank of South
Mountain. The disturbed area at the Site covers approXimately 550.acres (Figure 2). On the
north, this area is bounded by the deserted town of Summitville, and by Wightman Fork Creek.
. It is bounded by Cropsy Creek to the east, and the peak of South Mountain to the southwest. The
Site is located in the Rio Grande Drainage Basin near the headwaters of the Alamosa River. TWo
tributaries drain the Site - Wightman Fork Creek and Cropsy Creek. The confluence of Cropsy
.Creek and Wightman Fork is located on the northeastern perimeter downstream of the Site.
. Wightman Fork. Creek drains. into the Alamosa River approximately 4.5 miles below the Cropsy
Creek confluence. '"
1J...l Climate
The cmnate in the area where the Site is located is characterized by long cold 'winters and short
cool summers. Winter snowfall is heavy and thunderstorms are common in the summer (SRK, .
1984). Temperatures range from a high of 70°F and a low of 17°F in the summer to a high of
40°F and a low of -25°F in the winter. The Site receives an average of 55 inches of precipitation
annually, mostly in the form of snowfall, with annual evaporation at approximately 24 inches'
(Remedial Measures Plan, 1992).
. .
There is a relatively snow-free period of 5-6 months from May through October. This time .
period is regarded as the nCoriStrUctionseason..~ - Site ~ana operations dUring the. rest of the
year requires a significant amount of snow removal. Continued water treatment and flow, or
meticulous winterization, is required to prevent water from freezing in the pipes.
.LL2. TQpoi1'iphy .:
Approximately 550 acres of the Site is comprised of heavily altered terrain due to ~g
'operations. The Site's pre-1870 topography consisted of upland surfaces, wetlands, and South
Mountain peak. The predominant Site ground cover was alpine tundra at the higher elevations
with coniferous forest and subalpine meadow in the .1ower'elevatio~. The mountains which
surround the Site, including Cropsy Mountain to the south, are between 12,300 feet and 12,700
feet in elevation.
. The Wightman Fork drainage covers approximately 3.0 square miles upstream from the
Wightman Fork diversion. .The catchment elevations range from 11,225 feet to 12,754.feet. The
Cropsy Creek drainage 'area entails 0.85 square miles on the northeast slopes of the Cropsy
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Mountain and the southern slopes of South Mountain. Elevations within this drainage range
from 12,578 feet down to 11,200 feet at .the Cropsy Creek confluence with Wightman Fork
(Klohn Leonhoff, 1984). Wightman Fork drains into the Alamosa River approximately 4.5 miles.
from the Cropsy Creek confluence. "
Disruption of the topography began, on a limited scale, in 1870 with placer gold mining in .
stream- formed alluvial deposits. This placer mining was folloWed by open cut mining on gold-
bearing quartz veins. Underground mining followed. As mining production depths increased,
several processing mills were constructed to handle the increased capacity and produce a
concentrate suitable for transit. This initial mining phase lasted through 1890. AdditioDal
underground mining occurred from 1925 to 1940 and resulted in surface deposition of waste
rock near the adit entrances. Additionally, piles of mill tailings were pIaced downgradient from
, the stamp mills and the 1934 flotation-cyanidation mill. '
I:urther surface disruption of tJ;1e topography resulted from work in the late 1960's when'
. Wightman Fork was diverted north to allow construction of a dam and tailings pond. With this
new impoundment, mill tailings were put on the Beaver Mud Dump (BMD), and water was
impounded above the dam in the Summitville Dam Impoundment (SDl) (previously called 'the
Cleveland Cliffs Tailings Pond by Environmental Protection Agency).
The most dramatic surface alterations started in 1984 with the construction of the mine pits and
dumps by Summitville Consolidated Mining Company, Inc. (SCMCl) to support its open pit
heap leach gold mine operations. The main topographical feature is the highwall of South
Mountain. This highwall is ftactured and has a one to one (horizontal to vertical) slope.
l...l.J. GeolollY
Summitville is located near the margin of the Platoro-Summitville caldera complex. Rocks ~
the mine area consist of South Mountain.QWII1!Z.Latite,.porphyry::.The'?Jrphyry:is'underlaiJ:1:.~r '
the Summitville Andesite: The contact between the latite and andesite is intrusive, faulted in
some areas and is nearly vertical. On the north side, the contact is fiwlt-bounded by the .
Missionary Fault. South Mountain is bounded on the southwest by a.lqe northwest-southeast
. trending regional fault called the South Mountain Fault. The South Mountain Quartz Latite
Porphyry is bounded to the west, on both sides of the South MoUntain Fault, by slightly older
.Parle Creek Rhyodacite.. It is overlain at higher elevations by erosional remnants of slightly
younger Cropsy Mountain Rhyolite (Stoffregen, 1987). Figure 3 shows a geologic section of the
Cropsy Valley. '
South Mountain volcanic dome emplacement, alteration, and mineralization occurred in rapid
sequence approximately 22.5 million years ago (Rye, et. al., 1990). ~gyn~tic, sulfate-laden
water expulsed from the quartz latite mag11i~~ was hot and highly acidic (pH~2, temperature of
2500 C - Stoffregen, 1987)~ and caused extensive alteration to the quartz latite. Alteration occurs
, in fo~ sequential zoneS: the massive vuggy silica zone, the quartz-alunite zone, the quartz-
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kaolinite zone, and the clay alteration zone. The massive wggy sili~a zone is often a highly
porous zone in which all major elements but silica and iron were leaChed by acidic solutions and
replaced in places by excess silica. This zone occurs in iIIegular pipes and lenticular pods, and
generally shows greater vertical than lateral continuity (Stoffregen, 1990). The next outwardly'
occuning zone is the quartz-alunite zone, in which feldspars of the quartz latite porphryry were
replaced by alunite. This zone grades outward to a thin quartz-kaolinite zone, which is not
always present, and then into an illite-montmorillonite-chlorite zone in which feldspar and biotite
grains were replaced by illite and quartz, with lesser kaolinite and montmorillonite. The quartz-
alunite and clay alteration zones are the most volumetrically significant. Fine-grained pyrite is
disseminated through the groundmass'in all zones (Stoffregen, 1987). .
Summitville mmeralization is an example of epithermal Au-Ag-Cu mineralization associated
with advanced argillic alteration. Mi?ced mag1T1atic and surface water (derived from Snowmelt
and rainfall), less acidic and more reducing than the m~gm~.tic water that produced the alteration
zones, deposited metals and metallic sulfides at shallow «llan) depths (Rye, et al., 1990).
Mineralization is associated mostly with the porous vuggy silica zone, and occurs as covellite +
luzonite + native gold changing with depth to covellite + tennanite. Gold also occurs in a near-
surface barite + goethite + jarosite' assemblage that crosscuts the vuggy silica zone (Stoffregen,
1987). .
Post-volcanic geologic processes have been largely erosional. The two major streams that drain
the Site, Cropsy Creek and Wightman Fork, tend to follow the quartz latitelandesite contact.
Numerous springs and seeps occm at this junction between the fractured quartz latite porphyry
aquifer and the underlying dense andesite aquitard. '
Site cover material consists of topsoil, silt, clays, and gravel. The topsoil is described as,
grey/brown/orange, non-plastic with a trace of roots and sand. Clars are of low to medium
plasticity with some gravel:' " "." ." ., . " w" "', .... ,.. ", ,',' ,'.' ..'
'~ ~drogeology
Ground water at the Site is present as a series of intermitten~ shallow, perChed aquifers. Shallow'
ground water occms in surficial deposits consisting of colluvium, "slope wash" alluvium and/or
glacial ground moraine; and weathered parts of the Summitville Andesite. These.shallow
systems eventually discharge to surface water. The upper perched aquifer'system also contributes
to the ground water recharge of the fractured bedrock system. Numerous 5J'1#1gs and seeps cOver
the entire Minesite, the greatest number at the locus of the distal edge of the dome. Most of the
springs and seeps flow in direct response to precipitation, with high and low flows corresponding
to high and low flow of the surface water system in the area. '
A natural surface water drainage system eXists along the southern portion of the Summitville
Site. The surface water drainage system includes Cropsy Creek and Wightman Fork. Extensive
re-working of both drainage systems has been conducted. '
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LU Present Surroundini Land Use and Populations
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The Site is SUIfOunded by National Forest Service land (Rio Grande National Forest). The
multiple-use designation of this land gives it a high level of desirability for snow mobiling~ cross
country skiing, hiking, camping, horseback riding and picnicking. Additionally, logging activity
is on-going adjacent to Park Creek Road and other roads adjacent to the Site. During the summer
months, domestic cattle and sheep graze in the SUII'Ounding area and during the winter months,
the SUII'Ounding area is heavily used for hunting.
The distance to the nearest off-site building is 2.1 miles to the east (EP A, 1992). The water from
the Site flows past the town of Jasper into Terrace Reservoir, both of which are recreational
areas. Private residences and a Phillips University Camp use water from wells adjacent to the
Alamosa River. Below the Terrace Reservoir, the river flows past the town of Capulin which
contains two municipal wells and many domestic wells. Throughout this drainage area, homes,
'farmsteads and ranches depend upon: alluvial wells or river water for potable or agricultural water
production. However, recent EP A analysis indicates that the Si~ has not impacted alluvial
drinking water supply wells (Morrison Knudsen, 1994). Additionally, water from the Alamosa
River is used within the M9nte Vista Wlldlife Refuge and in the La Jara Creek system throUgh
the Empire Canal (District Court, Rio Grande Co.,1992). -
1.2
Site History and Enforcement Activities
L2.J. Site Hist0tY
PlaCer gold was discovered in Wighnnan Gulch in the summer of 1876 (Guiteras, 1938). The
lode deposit was found near the headwaters in 1873, and by 1875 open cut workings had been
established. The ore consisted of native gold in vein quartz, reportedly associated with limonite
and other ion oxides, .which comprised. the.surticial,-o~ -zone-of-the deposi~.. Because ~ .
zone' reportedly extended to 450 feet below the surface, adiis and shafts had to be driven into the
. veins (Garrey, 1933). There was only minor production in the mine area froui 1890 to 1925. .
In 1897, the Reynolds Adit was driven into the Tewksbury vein, located below the central
Portion of the contemporary Summitville pit. The Adit was .completed in 1906 (Knight Piesold,
. 1993). Reports of acidic water exiting the adit soon followed (Ganey, 1933)..
A significant gold find occurred in 1926 when high grade ore was struck. From 1926 to 1931~
864 tons of ore was extracted. The Reynolds Adit was rehabilitated to provide haulage and
development access. Plans were made to connect the Reynolds to the Iowa Adit, 540 vertical
feet above the Reynolds. This connection was completed in 1938. Iowa ores were then dropped
down to the Reynolds level for haulage. The Reynolds and the Iowa Adits also provided
drainage for the main workings (Knight Piesold, 1993). ..
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In 1934, a 100 ton-per-day flotationlcyanidation mill and gold retort was installed close to the
. south bank of the original Wightman Fork Creek. Records indicate that dewatering filtrate from
the flotation circuit was discharged directly into Wightman Fork throughout the mid-1930's.
In 1941. three tunnels were in ~peration: the Iowa, Narrow Gauge, and Reynolds. Duriilg World
,War II, the government mandated the termination of mining of non -essential minerals to. focus on
essential minerals needed for the war effort. Gold production ceased.
From 1943 to 1945, a high grade copper vein found in the Narrow Gauge and Reynolds was
developed. By 1944, only the Narrow Gauge Tunnel was operating. In 1947, the Reynolds W!!S
again rehabilitated. Approximately 4,000 feet of rail needed replacement due to deterioration
from acidic water. By 1949, the water flow discharge from the Reynolds ranged from 100-200
gallons per minute (gpm) (Stevens, T.A, 1960).
From 1950 to 1984~ the Minesite was the target of several exploration and underground
rehabilitation programs. Production of copper, gold, and, silver was sporadic. An extensive
drilling program was conducted by Tonto Drilling Services for ASARCO in the late 1970's and
early 1980's to delineate a potentially minable g~ld deposit (Knight Piesold, 1993). .
The underground ~d surface operations during the original discovery of gold to the early 1980's
resulted in surface deposition of waste rock near adit entrances and deposition of mill tailings
downgradient of the original mill. An attempt to process ore to extraCt copper content in the late
1960's and early 1970's resulted in a diversion of Wightman Fork from its original route to
further north of the existing ~gs, construction of the SDI (1969) and deposition of mill
tailings east of existing ta.ilings piles. . '
. .' .
During recent operations {1984-1991), Summitville Conso~dated Mining Company Incorporated
" (SCMCI)~ awhollY-Owned subsidiary of Galact:ic..~~~;lnc:;,; developed therern~inine
. mineral reserves as a large tonnage open pit heap le~h gOld-mine."'Goid'contalnlng'ore -(9.7
million tons) was mined, crushed and heaped onto a constructed clay-and-synthetic-lined pad. A
solution containing 0.1-0.5% sodium cyanide was applied to crushed ore on the Heap Leach pad '
(HLP) and was allowed to percolate through the ore, to leach out gold. The solution was then
pumped from the ore and gold was removed from the leachate with activated carbon. The
leaching solution was rejuvenated by restoring the target cyanide level and recycled through the
heap. Gold was stripped from the~n, precipitated from the stripping solution, smelted to
make doremetal,and sold. . .
The SummitVille HLP is a "valley:fill" design. This design differs from more widely employed
designs in that it is more of a lined depression, or rock filled pond, than a lined leaching "pad".
Uti1i7a.rion of a valley :fill design usually results from topographic limitations that make
constructio,n of a fI:ee draining pad difficult. The process solution was pumped directly from the
. HLP to the gold recovery plant. The more common leach pad design enables water percolated
through ore to constantly drain to a "pregnant solution pond." outside of the HLP, rather than
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"
being held in the ,same containment area as the crushed ore. 'The design of the HLP as a,'
continuous water containment structure prevents the natural drainage of water from the' cyamde
bearing pad and complicates the closure of the ore pile. '
. The HLP containment feature was constructed in a portion of the valley occupied by Cropsy
Creek. Cropsy Creek was moved to allow construction of the HLP. After diversion of Cropsy
Creek, a portion of the valley was enclosed by dikes. The area between the dikes was contoured
and lined and became the HLP.
Open pit mining operations conducted by SCMCI did not expose standing ground water in the
mine pit. Infiltration of surface water (derived from snowmelt and r-tinfa11) through the pit ~y
have resulted in elevated dissolved metal concentration in the water draining from the Reynolds
Adit. This trend is observed when compared to the available pre~pen pit drainage data.
Dming the SCMCI operation, topsoil was stripped and placed into stockpiles. Other overburden
and waste material was used for road and dike construction, placed into the Cropsy Waste Dump,
p~aced in the North Pit Waste Dump; and placed over ~e historic mill tailings to form the Beaver
Mud Dump. Difficulties in processing some of the ore resulted in formation of the Clay Ore
Stockpile, near the present solution pumphouse location, and an in-pit stockpile. Figure 2
illustrates these areas.
. .. .
The last ore tonnage was placed on the HLP in October 1991. Additi
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.- -. - 0_.-- -. ." _.._h .
" .-.- -.'--_. _0._0..__..
_.. . .
~
Corporation (ECC), under the direction of the USBR, began conducting engineering evaluations
~fthe water treatment processes and subsequently began improvements to water treatment
, processes and facilities.' , '
The Site was added to the Superfund National Priorities List (NPL) on May 31, 1994.
1.3
Community Participation
The Proposed Plan for the Summitville Mine Site was released to the public in August 1994.
, The Proposed Plan, the Focused Feasibility Study, and other documents in the Administrative
Record are available at 'information repositories at the following locations: Del Norte Public
Library located in Del Norte, Colorado; the Conejos County Agricultural and Soil Conservation
, Service located in La Jara., Colorado; and the EP A Superfund Records Center located in Denver,
Colorado. '"
Public meetings were held in Alamosa, Colorado to present the Proposed Plans and to take
,public comment. The comment period was extended 30 days to October 23, 1994. '
. '
Highlights of community participation are summarized as follows:
8
When EPA took over the Site ~ December 1992, there was a great deal of public interest, ,
mostly from fanners downstream of the Site who were concerned that their irrigation
water would be contaminated. As EP A. worked to reduce the chance for a large toxic spill
and began more water treatment at the Site, the farming community became satisfied that
there was. no imminent danger of conmminatipg their water supply. Since that'time there
, has been a decreased interest about the Site from the general public. The interest in the
, ,Site nationally has been vetjhigli due-tothe.meCliiuSilig-SUriimitVii1e'as;a.~red flag" -for -. , "
the need for mining reform.' '
,8
In June 1993, a Superfimd informational workshop was provided to the public in La Jara,
Colorado. '
8
On August 2,1993, a public meeting was held in Alamosa, Colorado describing
alternatives for reducing acid mine drainage from the Cropsy Waste Pile, tJie BMD, ,
Cleveland Cliffs Tailings Pond (now referred to as Summitville Dam Impoundment), and
the Mille Pits. An Engineering Evaluation/Cost Assessment (EElCA) fact sheet was
published. Public comment was taken until September 3, 1993;
.
The Community Relations Plan for Summi~e was written and distributed in
September, 1993. The Community Relations Plan provides a guide for EP A's community
involvement program based on interviews with local citizens. '
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"
, .
.
A Technical Assistance Grant (TAG) was awarded for the Site in February 1994. This
group is now well organized and has hired several consultants. The TAG Group has been
'active in the area in an attempt to generate interest in the Site. They have published'
regular Summitville columns in the Valley Courier newSpaper and have held
informational meetings.
'.
EPA held a. briefing for Congressional aides in May 1994.
.
Press releases have been written dealing with the following:
Proposal to place on the National Priorities List (NPL),
Listing on the NPL, "
Announcing meetings,
Availability of materials,
Comment periods,
Availability of work through bid process,
Bid awards, and, '
Status of work atthe Site.
.
Five Site Status Updates have been written and distributed to over 200 interested parties
as well as a year end report for 1993.
.
Articles about the mine were written by local newspaper writers and appeared at least
weekly for the past year. Files of these newspaper articles are available in the
Comm~ty Relations office and will be placed in the infonnation repositories.
In December 1993, the EP A produced ~d distributed copies of videos of the Summitville
. Minesite. One hundred fifty copies have been circulated to schools, officials and
. interested community members. The video gives an overview of the contamination at the
.site, a briefhistof}' -ofthe-.~'and-8""videcrtouru.:-"','~' ' " " ,
1.4
Scope and Role Qf Interim Remedial, Action within Site Strategy
The original mine permitted area includes 1,231 acres; the area referred to as the Site is
comprised of approximately 550 acres ofland disturbed by historic as well as recent mining
activities. The most common type of contamination associated with prQduction' of a metal mine
such as Summitville is the formation and discharge of large volumes of acidic water. The acid
generation can occur either chemically or biologically; as part of the living processes of certain
microorganism~. The acid is formed chemically when water, such as rainfall or ~owmelt, and
air come into contact with metallic sulfide ores. The sulfide (S-~ then reacts to form sulfuric acid
and sulfates. The sulfuric acid and sulfates react with the surrounding rock or soils to generate
the metal concentrations ~thin the acidic water and is then known as Acid Mine Drainage
(~). This process Continues as long as there is sulfide or suIfates~ water, and air.
8
.. . .: .
. ..._,.
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. '.." "-.'" .
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0- 0'.0 -"-'-----~
. w. .- -~--o- 0
- - '-- 0 -~-_.o
_. h -. H "
"
The primary metallic sulfides and secondary sulfates found 'at the Summitville Minesite are
pyrite (iron sulfide), alunite (potassium aluminum sulfate), and jarosite (potassium iron sulfate).
There are fourteen areas of concern at the Summitville Minesite including twelve which either
generate or may potentially generate AMD. The fourteen areas are briefly described below in
their general order of priority: .. .
1. HEAP LEACH PAD: The"liLP is approximately 55 acres in size and 127 feet deep at
its lowest point The Cropsy Creek was diverted around the HLP area and theHLP was
then constructed in the former Cropsy Creek drainage bed. The HLP is underlain by a
French Drain system and extends onto the toe of the CWP which is located upgradient
within the Cropsy Creek drainage bed. The leach pad liner ~ leaking, causing the water
within the French Drain to become CODtamin~ted with cyanide. The HLP consists of ore
containing high levels of metallic sulfides sitting in a vat of cyanide and heavy metals
. contaminated water. In December of 1992, the Environmental Protection Agency (EP A)
took over operations of the Site water treatment plant to prevent oveIt1ow of the
contaminated water to the Wightman Fork and, ultimately, the Alamosa River during
Spring runoff. Currently the HLP is maintained at a pH of 9 to prevent the evolution of
hydrogen Cyanide gas. It is currently proposed that the Heap be detoxified as one of four
interim actions. This action will also address the potential acidification of the heap once
the cyanide is removed and a high pH is no longer maintained. The former continuous
overflow of A1vID to the HLP from the adjacent CWP is currently being addressed as
discussed in #3 (Cropsy Waste Pile) below. .-
2. REYNOLDS ADq SYSTEM: The Reynolds System is composed of the
underground workings which still exist under the large open Mine Pit excavated by
SCMCl; and the remaining adits which access those workings. The Adits include the
Reynolds~ the Dexter Crosscut, the Chandler, and the Iowa. The Reynolds Adit is the
mairi adii which was' driven to dr3iri.t1iej}lOrmgs arid:ptDViCle an access and..halltage. .. " - .
route. The Dexter Crosscut, a drift .branching westward from approximately 100 feet into
the Reynolds Adit, also provided drainage, access, and haulage. The Chandler Adit
accesses the upper areas of the underground workin~ at a higher elevation than the
Reynolds Adit. The Iowa Adit accesses even higher levels of the wo~s and areas near
the rim of the Mine Pit. The Mine Pit was hydraulically connected to the Reynolds .
.. System and contributed m'!:Ch of the AMD obserVed at the ~eynol~. Adii The EP A
operated an interim treatment plant to treat ~e average 120 gallons per minute (gpm) of
AMD which exited the Reynolds Adit. ....
Based upon the estimated release of 44.5 percent oftota! copper loadings directly from
the Reynolds Adit, it was determined that plugging of this system be conducted as a time-
critical Removal action. A contract to plug the Reynolds Adit System was awarded on
October 4, 1993 and work began on November 22, 1993. After extensive technk:al
consideratioI1$, only the Reynolds and Chandler Adits were ultimately plugged. The
Dexter Adit was found to termin~te approximately 450 feet from its intersection with the
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,
" "
Reynolds so no plug was needed. Upon completion of the Reynolds plug, there was an
immediate decrease in flow and a"65 percent reduction in copper concentrations from the
Site overall. Copper loadingS directly attributed to the Reynolds Adit were decreased by
97 p.ercent.
On May 25, 1994,.the Chandler Adit was discovered to be discharging high volumes of
water from porous/fractured rock surrounding the plug. The leak was initially estimated
at 340 gallons per minute (gpm) and peaked at 725 gpm in June 1994 with high
concentrations of metals and low pH. However, this new contaminant source produced
less flow and less copper concentrations than experienced from the Reynolds Adit system
during the previous year. Work to fortify the Chandler plug was initiated in November
1994 and plug perfonnance will be closely monitored through the 1995 spring runoff
season. Since November 20, 1994, AM]) exiting the Chandler has been treated through
the PITS water Treatment Plant and no longer discharges directly to Wightman Fork.
3. CROPSY WASTE PILE: The CWP was composed of approximately 6.5 million
tons of low grade ore, overburden, and waste rock excavated from the main Mine Pit
during SCMcrs mining operations. The CWP covered approximately 35 acres and was
piled as high as 120 feet from the bottom of the old Cropsy Creek drainage bed in which
" it was placed. Although the C~ had been capped to prevent percolation of snoWmelt
" and rain&l1, upward infiltration of ground water has begun the process of acidifyiDg the "
" CWP and AMD discharges are occurring from the CWP. When the HLP was extended
onto the toe of the CWP, the French Drain system beneath the CWP was severed from the
system below the HLP. As a result, water backed up behind the ~er of the HLP into the
CWP - saturating that "part of the CWP and creating a 5 million gallon reservoir of highly
contaminated water within the bottom of the CWP.
" "
To prevent the overflow of AMD into the HLP, it was determined that the CWP would be
addressed as a non-time..critical.Re~aLaction.."During" development.ofltheEngineering
EvalUation/Cost Analysis report, it becaDie apparent that tlie"same reSponSe action woUld"
alSo apply to the SDI and B~, and that concurrent implementation would be cost
effective. The response action selected in the Action Memorandum #4 issued by EP A on
September 24,'1993 required consolidation of the various waste piles within the Mine
Pits. Because this work would require more than one construction season to comple~
" the design and actual construction were phased. Phase I work was initiated on October 1,
1993 and concluded in February 1994. During this time, approximately 927,000 cubic
yards of the Cropsy Waste Pile was placed in the Mine Pits. " The waste materials were
isolated from ground water by lining the surface of the Mine Pits with impenneable
material identified on-site. A protective layer of lime kiln dust was placed on the liner
prior to placement of the waste materials to neutralize any AMD generated during this
work. "
phaSe IT work was initiated in A1,1gUSt 1994. The CWP was completed in November 1994
10
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"
. . --~-=-=-:..~.""''''''-'-'-'
. and the SDIIBMD are expected to be completed in December 1994. Phase n will Imve'
moved an additional 3.5 million cubic yards of waste material to the Mine Pits.
..
Since Phase ill reinovai action work had not begun, EP A: evaluated the removal action
alternative selected in the Action Memo as one of its remedial alternatives for the CWP,
SDI, BMD and Mine pits. This alternative was ultimately seleCted as the interim
response action for those areas of the Site. This work will include coDStruction of a final,
impermeable cap and vegetation of the "footprint" areas below the CWP, SDI, and BMD.
4. WIGHTMAN FORK, ALAMOSA RIVER, TERRACE RESERVOIR (OFF- ,
. SITE): The release oflarge quantities of AMD from the Site have occurred since the
1870's when mining first began, though the concentrationS have significantly increased
since the begjnning of mining activities by SCMCl. Much of the AMD generated at the
Site finds its way into the Cropsy Creek or Wightman Fork creek, unless it is diverted for
treatment. The Cropsy Creek flows into the Wightman Fork at the southeastern comer of
, the Site. The Wightman Fork; located on the nortbem boundary of the Site, empties into
the Alamosa River approximately 4.5 miles from the Site. The Alamosa, in turn, flows
into the Terrace Reservoir about 18 miles from the Site. There are three small wetland
hab~tats along the Alamosa where several endangered species, including the bald eagle,
whooping crane, and peregrine falcon have been identified. The closest wetland is 1.8
miles form the Wightman Fork confluence; The other wetland areas are 4.2 and nine
miles downstream form the confluence. These wetlands are all upstream of the Terrace
Reservoir. Concerns regarding other water usage requirements, including drinking water
and farm inigation needs, are being investigated.
5. BEAVER MUD DUMP: The BMD encompasses 15 acres and c~nsi~ of
approximately 900,000 cubic yards of historic metallic sulfide tailings as well as
overbmden troIri SCMCrs 'operations~,:,It:is'iocatecHmmediately.mja.cenUo and south of
the Wightman Fork Creek and is a significant source of AMD. The BMD is alSo.," ,
infiltrated by ground water and discharges AMD to the Summitville Dam Impoundment.
this area is being addressed as part of the CWP Removal action and interim action. .
6. sUMMITVILLE DAM IMPOUNDMENT: Formerly referred to as the Cleveland
Tailings Pond, the SDI is.a historic sulfide rich tailings pond located within the former
Wightman Fork drainage bed. , The Wightman Fork was routed around the impoundment.
While the Impoundment only contains about 133,000 cubic yards of material, it is
thought to be hydraulically connected to the Wightma1l Fork and, therefore, providing
AMD directly into the creek. This area is being addressed as part of the CWP Removal
action and interim remedial action.
7. FRENCH DRAIN SUMP: The French Drain is a collection system which was
constructed underneath the CWP and HLP to intercept and route ground water flowing
from seeps below these units (CWP and HLP) back mto the diverted Cropsy Creek.
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"
Because much of this ground water flows through the CWP or becomes contaminated
with cyanide when passing below the HLP, it is currently routed to the water treatment
systems or pumped directly into the HLP. While the French Drain is not itself a source
generating contaminants, it serves as a point source discharge for contaminated water in a
. fashion similar to that of the Reynolds Adit system. . .
8. CLAY ORE STOCKPILE (Stockpile): The Stockpile is located jUst north of the
CWP and HLP border and was originally meant to be ore for placement on the HLP.
Because of its high clay content, SCMCI was unable to provide the special handling
. needed before the ore could be leached. The one million ton Stockpile was purposely
created because of its high content of metallic sulfides and'is considered to be a source of
. AMD.
9. MINE PITS: This is the location of the fonner orebody mined by SCMCI and the,
. location of the veins that were historically mined within the Summitville mining district.
The 100-acre Mine Pit has consumed most of the underground mine workings with the
exception of the Reyno~ds Adit System described .above. This area was and is highly
mineralized and contains high concentrations ofmeta1lic sulfides. Approximately.70
. million gallons of water (snow or rain) per year entered the Pit, passed through the
. remainine underground workings, and exited as AMD from the Reynolds Adit, prior to
plugging. The Pit is the origin of the rock in each of the tailings areas on-site and the ore
in the HLP. This area is being addressed as part of the CWP Removal Action and interim
action. At this time, the Pit has been filled by the waste material and is free draining.of
surface water.
10. THE NORTH PIT WASTE DUMP: This refers to a large area located north of the
Pit composed ofwaste rock and overburden from the. Mine Pit. It con~. relatively
. moderate amounts of met8llic sulfides and is a potential source of AMD. The northern
portion of.the dump,.primarily theslope.beloWsthe"1,1~8Q..bench, was-reclaimed.and
upper portions of the dump were iegraded With some Subsoil and tOpsoil 'placement' . A .. .'
. during .the 1991 operational season. Vegetation success has been limited due to high
wind exposure. '.. .
. .
11. GOMPERTS PONDS: These ~ a series. of small ponds, located approximately
. 400 feet north of the HLP, . that contained severely acidic and toxic metals contaminated
water and sludges. The ponds were excavated and then covered with soils. It is unknown
. if any sludges or contaminated' soils remain where the ponds were. If so~ this area is
another source of AA1D.' .
12. ACID ROCK DRAINAGE SEEPS: There are over 48 potential acid rock drainage
. seeps identified on the Site. These are areas where ground water naturally comes to the .
~ace though some may be a result of construction activities at the Site. The seeps have
not yet been evaluated to determine if they are an AMD source. .
12
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.~ ......."...~' .
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13. MINE SITE ROADS: Many of the roads at the Site were constructed with waste
. rock from the Mine Pit.. The material in these roads has not yet been evaluated to
determine if they are an AMD source. 0
.
14. LAND APPLICATION AREAS: There are areas where cyanide contaminated
AMD was sprayed onte? the soils as a treatment method. Aeration, as a result of spraying,
was meant to eliminate the cyanide contamination while the soils were supposed to
o °attenuate the metals. These areas have not yet been evaluated to determine if they are a
current AMD source.
Once these areas had been identified, the EP A was able to eStablish Remedial Action Objectives
(RAOs) for the overall Site. Pmsuant to 40 CFR section 300.43 (e)(2)(i), the RAOs were 0 0
established to provide remedial goals for the Site and were developed ~ consideration of current
regulatory guidelines, compliance with ARARs, and other identified limiting factors. The
sitewide RAOs for the Summitville Minesite are:
1.
Reduce or eliminate deleterious quality water flow from the Summitville Minesite into
the Wightman Fork. .
2.
Reduce or eliminate the need for continued expenditmes in water treatment for the
oSummitville Minesite. 00 .
3.
Reduce or eliminate the acid mine/rock drainage from the manmade somces on the
Summitville Minesite. 0
4.
00'
Reduce or eliminate any human health or adverse environmental effects from mining
operations downstream from the Site, to in~lUde the ~amosa River.
,...,.',. .: '.
. ,.. . ..'...'
. '. ~. .. .
5.0
Encourage early action and accelerati~n of the Superfund process for the Summitville
Site.
An analysis of meta1loadings attributable to each of the AMD source areas resulted in the
development of five primary areas of focus. Many of these source areas are in drainages or are 0
located where large amounts of surfu.ce or groundwater are available for continued generation of
AMD. The Cropsy- Wightman stream drainage system for the Site also serves as a way to .
transport the generated AMD contaminants off-site. The table below illustrates the copper
loarHnes and flows from these drainage points as Dleasured by SCMCI in July 1991. This
approach is also based on the water quality data regarding copper loading into Wightman Fork.
The table lists the contaminant somces, the yearly copper contribution to the creek from each
source, and the relative percentage loading of each source:
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"
CONTAMINANT SOURCES
SOURCE POUNDS OF COPPER PER . RELATIVE
YEAR PERCENT
Reynolds Adit 143,000 44.5
Cropsy Waste Pile 33,400 . 10.4
Heap Leach Pad
overflow potential 84,000 26.2.
French Drain 14,600 4.5
Summitville Dam Impoundment! 17,000 .5.3
Beaver Mud Dump
. .
Other 29,000 9.0
TOTAL 321,000 100.0
.
. .
Due to the size of the Site and extent of the contamination, the sitewide inteiim remediation'
activities are being addressed in five separate, though related actions. These five actions are:'
.
Plugging the Reynolds and Chandler Adits
Movement of the CWP, SDI, and BMD
. HLP DetoxificationlClosme
Sitewide Reclamation
Interim Water Treatment
.
.
. .
.
The first action of the cau.t.8.imiieD.trlSolation and-~~n project ~ th~'plugging'ofthe.
Reynolds and Chandler Adits. The second action is excavation of the CWP, SDI, and BMD,
. with subsequent placement of this ~al into the Mine Pits~ Both of these removal actions are
in progress under Emergency Response authority as discussed.above.
. .
The Phase m work for CWP,' SDI, and BMD, as well as the remaining tbre'e actiODs will be . .
.conducted as interim remedial actions. The CWP, HLP, and Reclamation work are expected to .
begin work during the 1995 construction season. The Water Treatment action will continue
without interruption though modifications in actual treatment processes may be implemented
during 1995.' .
~ Remedial Action Obiectives and Goals
This IROD addresses the reduction or elimination of dissolved metal contaminants, the
14
. . .
. ~ ..~ .
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~.~- ._.'~ -_..~-~_._- - .- -----_. -
"
transportation of metal conrnminants, and metal/cyanide complexes in surface water at the Site.
This interim remedial action is a temporary measure to treat water while point sources are being
stabilized. Reduction of contaminant load contributed by ground water or non-point sources
. requires further evaluation and may be addressed in future Site activities.
.
. .- . .
Water treatment contributes toWards the protection of human health and the environment.
Treatment of AMD and water containing cyanide is an interim remedial action contributing
toward the final sitewide remediation goals. .
- Implementing this interim remedial action will achieve protection of human health and the
environment. .The remedial action goals for this interim action are: . .
. -
.
Compatibility with sitewide remedial action objectives;
.
Reduction of .contaminated water impacts to the aquatic receptors in the
Wightman Fork, the Alamosa River, and the Terrace Reservoir during interim
remedial activities;' .
.
Flexibility in treatment of varied volumes and chemical makeup of water
requiring treatment; .
.
Minimi7.aUon of water treatment costs;
.
. Minimior.:ltion qftreatment waste products and waste disposal requirements; and.
.
Rp~1i'7.a.tion of practical resource recovery to lower overall treatment and Site
remediation costs.
. "1 '...: ..~.' ." .'. .~., ,.~. , '"
..~ ,.",' ..' ... ......, "":_" ..
. ,'. . .... 8~.. '..
1.5
Site Characteristics
.LiJ. Nature and Extent of Contamination
-
The EP A (1992) identified the Contaminants of Potential Concern (COPe) based on elevated
concentration and .potential toxicitY. of mobilized chemicals. The COPC will be 1]naH.,.ed upon
completion of the Baseline Risk Assessment. These concentrations were compared to Site- '. ."
specific background levels, which were determined by standard statistical analysis (Morrison
Knudsen Corp., 1994). Potential adverse effects on human health and the welfare of wildlife
were preliminarily assessed (EP A, 1992). The COPC identified for the Site are copper, .
cadmium, chromium VI, lead, silver, zinc, arsenic, aluminum, iron, mercury, manganese, and
cyanide. - . . .' .
All of these COnVlminants, except cyanide, are. found at the Site in naturally occurring minerals
15
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"
and compounds. They are made soluble d~g the AMD-generatiIig chemical process. The
AMD process is accelerated by the mining activities which took place at the Site. .
1.5.1.1
Acid Mine Drainage
At Summitville, mining activities resulted in additional sulfidic material sUrface area available
for contact with oxygen and water. Air and water contact with the additional surface area
provided by broken rock accelerates oxidation of minerals and creation of low pH drainage. This
drainage water is high in acidity, sulfate (S04).2 ions, and dissolved metals.
.
AMD water contributes metal loads to Wightman Fork and the Alamosa River. "This creates
adverse conditions preveIifuig the growth and maintenance of a healthy aquatic ecosystem.
These adverse effects have been noted in various studies of water quality of Wightman Fork and
the Alamosa River. "
1.5.1.2
. Water Containing Cyanide
Commercially manufactured sodium cyanide (NaCN) was used at the Site for extracting precious
metals from ore. grade materials. :CYanide has been used for this purpose in the ~g industry
since the late i 800's. Cyanide is found either in simple form or in combination with other
elements. Simple cyanide forms designated as "free" cyanide are the cyanide radical, CN-, and .
hydrogen cyanide, HCN. Cyanide also combines or complexes with alkali metal ions~ heavy
metal ions, and transition elements. The complex cyanide bonding is VeIy strong, moderately
strong, or weak (defined by tendency to disassociate in an acidic environment). Presence of
excess hydrogen ions (acid) will lead to the formation ofHCN, depending on the strength of the
metal/cyanide bond.
Cyanide content is found in residual process water contained in the HLP. The predominant form
of cyanide in solutionisa Weak.Acid.D~le,{WAD)eomplex"(complexthat,has a " '"
. moderately strong bond and dissociates at a pH of 4.5 or greater) With copper. Complexes with
other elements - silver, sulfur, gold" iron "and others - are also present Thiocyanate (SCN) is
present in' significant quantities. The thiocyanates may migrate through the water tteatment train
into Wightman Fork. The pH of contained residual..process water within the HLP averages about
9.3. "
Leaks in the HLP containment liner result in the presence of cyanide in drainage that surfaces
downgradient of the HLP. These drainage streams (from the Valley Center Drain (VCD), and
several seeps in and below HLP Dike 1) are mixtures of residual process water,.AMD, and
ground water. The AMD portion results in low pH (2.5'; 3.5), and cyanide exists as either a
metal/cyanide complex (primarily with copper), or as free cyanide (HeN). These streams are
routed to the French Drain Sump to prevent release to Wightman Fork and AIamosa River
drainages. The water is pumped to the HLP and niixed with residual process water~ or treated
separately. . "
16
"::.::;".
::.~.,... ..--
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fl.
1.5.1.3
Description 01 Impacted Water
. Ta~les 1.-. 6 ~arize data collected during water monitoring before treatment and during
discharge of surface water to Wiehtman Fork. The tabies include recordings of copper and
cyanide loadings from May 1993 thi-ough June 1994. During this period, monitoring emphasis
was given to copper and cyanide because these were the chemicals of highest concentration
during the ERRA. There was also a concern because of the potential toxicity of cyanide.
Table 1 shows data representing the copper load (1bs.) transported by the Site water. The first
group exhibits copper load from water pumped from the French Drain (FD) Sump. This sump
contains water from the VCD and AMD seeps.' . . .
. The second data group within Table 1 illustrates the copper concentration of water contained in
the HLP. This includes water pumped from the FD Sump, water that surfaced at the toe of the
CWP, and.process water contained in the HLP. All water in the HLP is treated to remove
cyanide and copper, as well as other metals, before release to Wightman Fork. .
The underground worki:ngs section presents data on copper load that was transported by water
exiting from the Reynolds Adit and the Chandler Adit. Also shown is the amount of copper'
removed through treatment at the Portable Interim Treatment System (pITS). '. The PITS treated
water exiting the Reynolds Adit, the Iowa Adit, and som~ conta.minant surface runoff. The plant
was deactivated after the Reynolds Adit plug was completed. . .
. .
The reJIlaining sections of the table present the copper content of surface water discharged into
Wightman Fork during'this time period. These include water from Cropsy Creek, seep LPD-2
(which feeds into Cropsy Creek), and Pond P-4 (a sediment pond that receives surface nmoff .'
from the mine pit area, haul roads, and other nmo£}). Other streams that contributed copper load
to Wightman .Fork-include drainage-from the.g~}F~-~~i.the.cla~~._~~o~kpile,~d,. ',..
treatment p~ant efiluent . . . ".
Also shown'are the pounds of copper that would have been added to Wightman Fork if water had
flowed into Wightman without treatment. Annual totals from July 1993 to June 1994 are given to
the right of monthly totals. The twelve month period, July 1993 through June 1994, represents
the time frame when existing treatment facilities utilized maximum capacity.
Table 2 shows monitored cyanide loading (1bs.) or the potential for cyanide loading to Wightman
Fork during the same period. .
Table 3a shows monitored flow rate for streams which are capable of carrying contaminant load
to Wightman Fork. High and low flow rates illustrate seasonal fluctuations. Combined monthly
totals illustrate potentially required treatment volumes. .
Table 3b shows the total gallons for streams capable of carrying contaminant load to Wightman
17
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fl.
Fork. This table also shows the treatment plant capacity measured in total gallons.
Table 4 shows other monitored constituents (manganese and iron) that should be taken into
consideration in the selection of treatment processes. Manganese removal to <1 mglliter is
necessary before cyanide destruction can take place. Significant iron content can produce sludge
volumes that affect plant efficiency. .
Tables 5 and 6 show copper and cyanide concentrations monitored at station WF 5.s on
Wightman Fork from May 1993 through June 1994.
~
General descriptions of monitored surface water affected by conditions at the Site are given
below. FigUre 4 shows contaminated surface water streams.
. Stream A - The Va/l~ Center Drain IV~)
General: Comprised of drainage from the CWP, ground water from beneath the HLP,
and leakage from HLP containment. Contains cyanide as a result of leakage from the
HLP. CWP drainage contributes low pH and elevated ~etals.
. Volume: . Significant flow throughout the year. Peak flow is concurrent with spring
snowmelt. High flow (78 gpm)recorded in April 1994; low flow (57 gpm) was recorded
in June 1993. .
Loading: Based on copper as the indicator, the VCD ranked as the 4th highest peak flow
caIrier of metals. 8,473 lbs. of copper dissolved in solution. were transported by drainage
from July 1993 through June 1994. .
Stream B - CrDl1$Y Waste Pile Draina¥e
. . ~." . .
General: Comprised of ground water flow from seeps ~d upgradient drainage through
colluvium and alluvi~ (-Geraghty & Miller, 1992): Includes precipitation (snowmelt
and rainfall) infiltrating through mine waSte materials. Significant aluminum content
effects must be considered when selecting a treatment process. Volume and makeup are
expected to materially change with planned relocation of CWP materials.
.. "~ - - .
. .. ..
Volume: .Seasonal release to the surface at the toe of the CWP.'Y ear round contribution
to the VCD. High flow (364 gpm) recorded in May 1993. Surface flow was not
observed at the toe of the CWP between January - April 1994.
Loading: Based on copper as the indicator,.water surfacing at the toe of the CWP is the
second highest peak caIrier of metals. 23,305 lbs. of copper dissolved in solution were
transported by drainage from July 1993 through June 1994 (includes water sent to the .
CwrP).
18
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"
Stream C - Drainafe from Underground Workines
.
'General: Comprised of groUnd water and precipitation (snowmelt and rainfall) .
infiltrating the mine pit area. . These infiltrating waters draining through miIieraIized rock
into the rem~ining underground workings have historically surfaced as flow from the
Reynolds Adit. Comparatively less water volume drains from the Iowa Adit. The'
Reynolds and Chandler adits have been plugged. The long-term effects of plugging the
Reynolds Adit in February 1994 and Chandler Adit in M3rch 1994, an~ the consequent
rise in the South Mountain water table have not been determined. In May 1994, an AMD
stream developed as discharge from the Chandler Adit. It has been observed that the
. water is flowing between the top of the plug.and the roof of the adit (Abel, pers. comm.,
1994). p~ flow from the Chandler Adit leak in June 1994 was 661 gpm with a copper
concentration of 409.40 mg/l and a pH 0~2.16, determined by sampling the streamjust
outside the adit entrance. This was almost "instantaneous" (the discharge increased from
o gpm to 661 gpm in 11 days), indicating a direct relationship between the rise in the
South Mountain water table and the filling of the adit system with water. By the end of
July 1994, the flow of the AMD stream decreased to 130 gpm with a copper content of
268 mg/land a pH of2.30. Eventual volume of AMD that may require treatment is .
unknown. Corrective measures are planned.
Volume: Significant flowtbroughout the year. High flow from the Reynolds Adit (763 .
gpm) was recorded in June 1993; low flow from the Reynolds Adit (6 gpm) was recorded
in April 1994.
Loading: Based on copper as the indicator, Stream C is ranked as the highest peak flow
carrier of metals. 198,221 pounds of copper dissolved in solution were transported by
drainage 'from.July. 1993 throughJune4994~".P.eak.flaw of-MAD. ,fu>m tte underground
workings in June 1994 was 14% less than flow in Jime 1993.- CopperIoad from' ..
underground workings in June 1994 was approximately 23% less than the load in June
1993 (Table 4). In JUly 1994 volume from the underground workings was 25% less than
in July 1993.. Copper load from underground workings in July 1994 was 15% less than in
July 1993. '. .
" '--,'. '..
Stream D - Summib!ille Dam 11lJl'oundment and Beaver Mud Dump drainare .- '''..
General: Comprised of the surface drainage into the tailings pond and surrounding area,
and the ground water.migration through the mud dump. Possible ground water migration
through tailings contained in the pond. Includes precipitation (snowmelt and rainfall)
. infiltrating through BMD materials. Volume and makeup of this stream is expected to
materially change with planned solid waste relocation in 1994-95 (Cropsy Phase n
op~ons). . .
19
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"
Volume: High flow (202 gpm) was recorded in May 1993; low flow (33 gpm) was
recorded in November 1993. Monitoring was not possible ftom 1anuary 1994 through
April 1994, due' to snowpack.
. .
Lo~ding: Based on copper as the indicator, Stream D is ranked as the third highest peak .
flow carrier ofmetaIs. 12,294Ibs. of copper dissolved in solution were traIisported by
drainage from July 1993 through June 1994. .
Stream E - North Pit Waste Dump d,ainare
General: Comprised ~y of surfuce runoff ftom Waste dump materials. .There is
some ground water seepage. .
Volume: Significantly varies with precipitation (rainfall and snowmelt). Affected by
spring runoff. High flow (284 gpm) was recorded in May 1993; low flow (1 gpm) was
" recorded in. October 1993. Monitoring was not possible ftom November 1993 through
April 1994, due to snowpack. .
. Loading: Based on copper as the indicator, Stream E is ranked as the 6th highest peak
flow carrier of metals. 4,321Ibs. of copper dissolved in solution were transported by
drainage from July 1993 through June 1994. .
Stream F - ClIO' Ore Stockpile Drainare
General: Comprised of sUrface drainage migration through lower portions of the waste
dump and Precipitation (snowmelt and rainfall) infiltrating through upper level materials.
W~.migrating ftom beneath the CWP may also contribute.
Volume: High flow (66 gpm) was recorded in June 1993; low flow (37 gpm) was
recorded in May,1994> .". '.. '0.- ":' . . .'''. ..'.'. "'. ". , . .
Loading: Based on copper as the indicator, Stream F is ranked as the 8th highest peak
flow carrier of metals. '1,113 lbs. of copper dissolved in solution ~ transported by
drainage from July 1993 through June 1994.' .
Stream G - Sediment pond P-4 d,ainare
General: Comprised of surface drainage from upgradient disturbed areas. Includes some
contribution from Iowa adit drainage. .
Volume: Highly variable, dependent on precipitation events. High flow ( 948 gpm) was
recorded in May 1994; low flow (4 gpm ) was reco~ed in November 1993.
. .
Loading: Based on copper as the indicator, Stream G is ranked as the 5th highest peak
flow carrier of metals. 4,508 lbs. of copper dissolved in solution were transported by
20
.", '"
"'. .-
-. ~ . -,
"'"
. ,"",...."
.. ... - .
.... .' .
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"
ckainage from July 1993 through June 1994.
. Stream H - Drainage from CrQp$J' Creek
-
General: Comprised of surface drainage from upgradient undisturbed areas. Rerouted
around the CWP and HLP areas during SCMCl operations. Receives some metals
loading from surface runofffroin the CWP and seep LPD-2, downgradient from the HLP
and Dike 1. May receive loadings from effected ground water. Route does not go
through sediment control features. .
Volume: Peak flow is concurrent with spring runoff. Significantly affected by .
precipitation.( snowmelt and rainfall). High flow was recorded in May 1993; low flow
was recorded in February 1994.
Loading: Based on copper as the indicator, Stream H is ranked as the 7th highest peak
flow carrier of metals. 1,737 Ibs. of copper dissolved in solution were transported by
. drainage from July 1993 through June 1994.
. .
The affected stream segments are summarized in the following table. The streams are ranked in
decreasing order according to the metal load during peak flow. .
Rsnking ofSurfac:e Water Streams at Peak.Flow
without Operation of CWTP, CDP and MRP
Metal Load at Stream..
Peak. Flow.
1 Stream-C~' Undergrc>UIId:~Worlcings'~e:";
2 Stream B- CWP Drainage
3 Stream D- SDIIBMD Drainage
4 Stream A- VCD"
5 Stream G- P-4 Drainage - " .
6 Stream E- NPWD Drainage
7 Stream H- Cropsy Creek Drainage
8 Stream F - Clay Ore Stockpile Drainage
~. .." :.' I .
.
Rankings are listed in decreasing order.
Table does not include the HLP wastewater stream.
..
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"
. .
French Drain Sump Int10ws
The FD Sump was originally constructed to prevent drainage from the VCD (Stl'eamA) from
. entering th~ Cropsy Creek" and Wightman Fork. A collection and pumping facility was installed .
after VCD drainage was found to contain cyanide. The smnp was also utilized to contain other
contam;nated water. These drainages (described beiow) were found to be contaniinS'lted in later
years. Tables 1 - 3b summarize data for copper, cyanide, and water volume for these streams.
General descriptions follow.
FD Sump -1 Seepage from Dike 1
Gener3I: Comprised ofwater exiting a point at the base of Dike 1.
Volume: Peak yolume (1,785,600 gal., June 1993) is concurrent with spring snowmelt
Loading: At peak flow, Stream FD Sum~l1ransports up to 83 lbs of copper per day.
Load declines to less than 3 lbs per day as flow decreases.
FD Sump -2 Seepage from the Dilce 1 ramp
-General: Comprised of water exiting a point on the access road that flanks Dike 1.
Volume: Peak volume (820,000 gal. in June 1993) is concurrent with spring snowmelt
Flow ceases soon after the peak snowmelt period. Water is acidic, and contains cyanide..
L~ading: At peak flow, Stream FD Sum~2 transports up to 5~71bs of copper per day.
Load declines to less than 1. lb. per day as flow decreases. -
FD Sump -3 Drainagefrom benetith the HLP.
, . "'. : ~ 1 . '." ,J.. ',. .: .., ... .. "", ~ .
. "',"
. . ~ . '.
- . .
General: Comprised of water exiting rock drains built to divert water during HLP
construction at 11,510 and 11,53Q elevations.. Discharges- are combined and routed to the
FD Sump. There is a wide range in copper' content' Contains a slight amount (0.12 mg/l) .
of cyanide at ~ volume disCharge. - ,. - .
- - ,"
'. . .
Volume: ~eak volume (1,116,000 gal. in June, 1993) is concurrent with spring .
snowmelt Significant flow continues throughout the year.
Loading: At peak flow, Stream FD Sum~3 transports up to 27lbs of copper per day.
Load declines to less than 1 lb. per day as flow decreases.
22
-.
. ~.. .,
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fl.
l..U Contaminant Tran~ort and MifPCition
.1.5.2.1
Surface Water
.. .
Surface water is considered the most significant media for off-site transport of metals. Surface
.water has been impacted by mining operations from the Site throughout the reach of Wightman
Fork, from the Site to the Alamosa River, and within the Alamosa River from Wightman Fork to
Terrace Reservoir and points further downstream. According to the Conceptual Sitewide
Remediation Plan prepared for the EP A, it has been determined that the Site is the predominant
source of metals loading to the Alamosa River system.
- . .
.' . .
As pH of water rises' from the addition of water with higher pH, iron precipitates from solution as .
a hydrated iron (ITI) oxide product (ferric hydroxide). This forms the red or yellow staining seen
on rocks in the streams or on banks. Copper, cadmium and zinc will co-precipitate with iron
precipitates. Metals concentrations are further reduced by dilution from downstream tributaries.
COPC could be biologically transported through an aquatic food chain, and could be transported
to birds, animal~ and hnman~, The Baseline Risk Assessment (BRA) has not been completed;
however, qualitative ~ analysis has been perfonned by EP A which verifies this data (ERT,
1993). The BRA is scheduled for completion in 1995. Currently, the full range of CO PC is
being reassessed and additional contaminants of concern (COC) may be identified in the BRA.
1.5.2.2
Ground water
. .
Ground water depths vary at the Site. In general, water levels are relatively close to the surface
except in the vicinity of the old uiine workings where depth to water can be as much as 300 feet
The old workings act as effective underdrains. This can' be seen by the flow of water from the
adits. It is anticipated that the ground water level will rise as water backs .up behind the plugged
ReynoldsandChandler:Adits;.::.....,:... ""V . ...., . . .
'. ,. ....
The ground water occurs in smficial deposits consisting of colluvium, allUvium, andlor glacial
moraine; and fractured andesite of the Summitville Formation. Ground water flow is within the
wea$ered and fractured bedrock and, within alluvium near the Cropsy Creek and Wightman
Fork channels. Grourid water flow and metals are capable of being transmitted to Wightman
Fork through the alluvial and.bedrock systems. Ground water is generally shallow (0.2 to. 25 feet
within the alluvium).andflows northeast in both the Cropsy and Wightman Fo~.drainages.
. . -
Shallow gro~d water at the Site is present as a series of intermittent, perched systems. The .
perched aquifer system contributes to recharge of the shallow fractured bedrock system. No
regional ground water table has been identified at the Site. The ground water close to the surface
is strongly influenced by precipitation. Dming spring runoff, these shallow systems discharge to
surface water. Numerous springs and seeps are evident throughout the Site and.most flow in
direct response to precipitation.
23
. , .
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fl.
1.5.2.3
Soil and Air
Site cover consists of topsoil, silt, clays, and gravel. The topsoil is described as .
greylbrown/orange, non-plastic with a trace of roots and sand. The clays are low to medium
. plastiCity with some gravel. The gravel is indicative of colluvial deposits or tailings. The
disruption of the surface soils may be a secondary source of excess metals migration.
.LU ARARs
.'
ARARs'are "applicable" or "relevant and appropriate" requirements offedera1 or state law which
address a hazardous substance, pollutant, contaminant, remedial actiOn, location or other
circumstance found at a Comprehensive Environmental Response, Compensation, and Liability
. ACt of 1980 (CERCLA) Site. Refer to Table 7 for a detailed summary and discussion of ARARs.
The NCP defines "applicable" requirements as cleanup standards, standards of control, and other
substantive environmental protection requirements, criteria, or limitations promulgated under
Federal or State law that specifically address a hazardous substance, pollutant, contaminant,
remedial action location or other circumstance found at a CERCLA site. "Relevant and
appropriate" requirements address problems or situations sufficiently similar to those.
encountered at the CERCLA site that their use is well suited to the environmental or technical
factors at a particular 'site: (See 40 CPR Section 300.5.)
ARARS are grouped into three categories:
.
.
.
Chemical Specific
Action Specific.
Location Specific
Chemical specificARARs include health or risk based narrative standards, numerical values, or
methodologies that, when applied tQ site-specific conditions. establish the acceptable .amount or
concentration of a chemical that may remain or can be released to the enViionment Action ,. '-- -
specific ARARs are usually technology or activity-based requirements or'limitations on actions
taken. with respect to hazardoUs substances, pollUtants, or contaminants found at CERCLA sites.
Location specific ARARs are restrictions placed on the concentration of hazardous substances,
pollutants, or contaminants or the condUct of activities solely because they occur in special
.locations. Examples of specia1locations include floodplains, wetlands, historic places and
sensitive ecosystems or habitats. (See "CERCLA Compliance with Other Laws Manual Draft
Guidance," EPAlS40/G-89/006(August 1988.) .
.
In addition, the NCP has identified a fourth category of information "to be considered" when
evaluating remedial alternatives, known as TBCs.TBCs represent Federal and State advisories,
criteria or guidance that are not ARARs, but are useful in developing CERCLA remedies. (See
. 40 CPR ,300.430(g)(3).)
'24
A..
.....
-
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"
..
The analysis of ARARs has been limited to the'scope of the interim action. The.NCP allows
waiver of ARARs for interim remedial measures that do not exacerbate site problems or interfere
. with final remedy (40 CFR 300.430(f)(I)(ii)(C)(I) and 55 FR 8747). Other ARARs may be
involved in enacting final remedy(ies). .
The sitewide ARARs were identified in the addendum to the HLP FFSs. In response to
comments submitted during the public participation process on the CWP FFS and Proposed Plan,
however, EP A is further defining the applicable or relevant and appropriate requirements from
Federal and State laws or regulations which must be met by any alternative implemented ~ the
CWP interim remedial action. Since the sitewide ARARs have already been identified in the
"ARARs Addendum, to the HLP Focused Feasibility Study Report", this further refinement of
ARARs as they relate to the CWP !ROD represents only a minor change to the CWP FFS and
Proposed Plan. Consistent with its."Interim Final Guidance on Preparing Superftmd Decision' '
Documents", OSWER Directive 935'5.3-02 (June 1989), EPA has deteImined that this minor
change will have little or no impact on the overall scope, performance, or cost of each alternative
as originally presented in the CWP FFS or Proposed Plan.' . .
The following sitewide ARARs, or relevant portions of the sitewide ARARs, must be met in
accordance with Section 121(e) ofCERCLA and 40 C.F.R. 300.430 of the NCP by each
potential CWP interim remedial action alternative:
J.. 5. 3. 1
Chemical Specific AJURs
. Surface Water ARARs,
The Colorado Water Quality Standards (CWQS) ~lish a system for classifying state
smface waters and procedures and criteria for assigning numeric water quality standards.
(See 5 CCR'1002-8;'Sections"3.I~Othrouglr~,1;:l7.;):,,:, " ,,' ,
. ... ," ,", .
'0
Colorado Water Quality Standards, Applicable
. . -
Criteria for Stream Classification
The CWQS require that surface waters be:
classified for the present beneficial uses of the water, or the beneficial uses that
may be reasonably expected in the future for which the water is suitable in its
. present condition or the beneficial uses for which it is to become suitable as a
goal.... Where the use classification is based upon a future use for which the
waters are to become suitable, the numeric standards assigned to such waters to
protect tb,e use classification may require a temporary modification to the
underlying nUmeric standard... (See ~3.1.6.)
25
.." ._. ~-.
...-.' .
. -
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"
The CWQS employ four broad types of beneficial use to flame the classification process:
.
.
.
.
recreational
aquatic life
agriculture
domestic water supply
Recreational Use
The recreational uses are divided into two classifications. Recreational Use, Class 1 - PIimary
Contact, addresses surface water quality concerns where ingestion of small quantities of water
during the use is likely to OCCUI'. . Recreational Use, Class 2 - Secondary Contact, focuses OD
, streamside activities where ingestion of water is unlikely to occur. The effect of the recreation
classification on numeric water quality criteria is limited, the primary consideration being the
concentration of fecal colifomi bacteria. The Summitville Minesite is unlikely to contribute
bacteriaI contamination to the watershed. For that reason, the recreational use clasSifications
have been met and will not be considered further. '
Aquatic Life
Two aquatic life classifications are currently promulgated for stream segments of interest. Class.
1. cold water aquatic life is defined as: '"
... waters that (1) CUIIently are capable of sustaining a wide variety of cold water biota,
including sensitive species, or (2) could sustain'such biota but for coIIeCtable water
quality conditions. Waters shall be considet:ed capable of sustaining such biota where
physical habitat, water flows or levels, and water quality conditjOI1$ result in no ,
substantial impairment of the abundance and diversity of species. (See ~3.1.13(1)(c)(i).)
. ,". -. ,,"# "', .,.. -."'" ~..' :'. .'~' ~.' '. .'~ ..,' .;;.~ ,':
, 'Class 2 cold and waml water aquatic life is'detined'as:':_-" - . .
.' '''.. "'. ','~' .
. ,
. -, ..
, .
... waters that are not capable of sustaining a wide variety of cold or warm water biota. .
. including sensitive species, due to physical habitat, water flows or levels, or incorrectable
water quality conditions that result in substantial mq,aiIment of tbe abundance and
diversity ofspecies~ (See ~3.1.13(l)(c)(iii).) . .
- .
, .
Domestic Water Supply
Domestic water supply is defined as:
...suitable or intended to become suitable for potable water supplies. After receivin~
standard treatment ...these waters will meet Colorado drinking water regulations... (See
~3.1.13(lXd), emphasis added.) . .
26
"..., - ..
. . ",.,,". ..
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~
Agricultural Use
Agricultural use is defined as:
...suitable or intended to become suitable for irrigation of crops usually grown in
Colorado and which are not hazardous as drinking water for livestock... (See
~3.1.13(1)(b).) ..
Three segments of the Alamosa River are classified for various uses according to this syStem:
Segment 6, the Wightman Fprk at and below the mine; Segment 3b, the Alamosa River from ..
immediately above.the confluence With Wightman Fork to Terrace Reservoir; and Segment 8,
Terrace Reservoir. Figure 5 shows segments .ofthe Alamosa River Basin. . .
Segmenf 6 is. classified for Recreation Class 2 and Agriculture. It is not classified for aquatic
life. No numeric water quality standards have been assigned. The lack of an aquatic life
classification was based on testimony received at the Colorado Water Quality Control
Commission (WQCC) hearing. The WQCC determined that an aquatic life classification cannot
be attained within 20 years. .
Segment 3b is classified as Class.1 Cold Water Aquatic Life. Numeric Standards are set for
surface water downstream of the confluence of Wightman Fork and the Alamosa River.
Terrace Reservoir is classified as Class 2 Cold Water Aquatic Life. This classification.
recognizes a limit on the ability of Terrace Reservoir to sustain a diverse aquatic community.
Numeric Water Quality Standards .
'. . ~ .'
.'- . ..
. ." -. '... .
The CWQS provides a three-tiered structure for establishing numeric water quality standards.
. For unimpacted high quality waters, numeric levels known as the "Table Value Standards"
(TVS) are established and presumed to be protective. For impacted waters where pollutant.
concentrations exceed rvS values but the beneficial uses are adequately protected, Ambient
Quality-Based Standards.c3n be adopted. For impacted waters where beneficial uses are not
cmrently adequately protected, TVS are adopted as a goal. Temporary modifications to numeric
. standards may be adopted in these areas. .Where classified uses are not being protected and a use
attainability analysis has found nonattainability, Site-Specific-Criteria~ Based Standards can be
developed. The TVS and Ambient Quality-Based Standards are applicable regulations. for
determining compliance with surface water discharges at the Site. Segment 3b of the Alamosa
River is downstream of the Site at the confluence of the Wightman Fork and the Alamosa River.
These regulations were used to establish promulgated standards in this segment of the Alamosa
River. Specifically, the Classifications and Numeric Standards for Rio Grande Basin are found
in Section 3.6.6. of the regulation. Table 8 illustrates these levels. These standards are
categorized into acute and chronic limits. . Acute limits represent an upper level not to be
-------
"
. .
exceeded in any 24 hour period. Chronic standards are average. levels which can not be exceeded
in a 30 day period.
Table Value Standards
The TVS are based upon the Federal Water Quality Criteria. The TVS, however, have been
adjusted to protect the beneficial uses of Colorado waters (See ~3.1.7(b)(i).) The TVS for
aluminum (acute), arsenic (acute), lead (acute/chronic), nickel (acute/chronic), selenium
(acute/chronic), silver (acute/chronic), zinc (acute/chronic), chromium VI (acutelchronic),
chromium ill (acute), mercury (chronic), manganese (chronic), cadmium (acute/chronic), pH, .
dissolved oxygen, Fecal Coli, ammonia, chlorine, sulfide, boron, nitrate and cyanide are set at
Segment 3b. It is important to note that many of the TVS for protection of aquatic life from .
metal pollutants are hardneSs dependent. The WQCC has adopted an acute and a chronic copper
standard for Segment 3b. The acute copper standard for Segment 3b is established'using the
TVS; however, the WQCC has adopted a less stringent temporary modification to this standard
based upon WQCC hearing testimony. The EP A has adopted and will meet the ambient quality
based chronic copPer standard as applicable for this interim action and is not using the less
stringent acute copper standards ft:om the TVS or the less stringent August 1994 temporary
modification. The IAL, as monitored at WF-5.5, were developed to meet the more stringent
ambient quality-based chronic copper standard at Segment 3b. .
Ambient Quality-based Standards .
Ambient quality-based numeric surface water quality standards are the mechaniS1'T\ where limited
water quality impacts are controlled through less stringent water quality standards. Ambient
quality-based standards are specifically intended to address circumstances where natural or
iIreversibl~ man-induced ambient water quality levels are higher than the specific numeric levels
. contained in the TVS Tables I, ll, and ill, but are determined "adequate to protect classified .
. uses." (See ~3.1.7(1)(b)(q).) The ehronic.standard.for..coppeds established..at Segment 3~ using.
this regulation. Copper is one of the primary contaminants of cone em' for water quality. The
chronic copper standard was used as the most strict ARAR for copper at the Site. The interim
. action levels (IAL) were developed using this standard. The chronic standard for iron also falls
into . ambient water quality standardS. There are no ~ iro~ standards.
.-.-..4"0 evaluate the ability ofaItematives to meet the stIeaw classification and numerical standard of
the CWQS MARs, EP A established interim action levels (IAL) for water quality. . These IAL
can be found at page 23 of the Water Treatment FFS. The IAL are developed using a model
which utilized high flow and low flow average concentrations of the contaminants to set
threshold loading~ allowable at Wightman Fork monitoring point 5.5. Numerical standards that .
would enable the river water quality to meet the water quality ARAR at Segment 3b under
average conditions were then calculated. Based upon the WQCC numeric water quality
standards for Segment 3b, the TVS levels were used for all COPC at the Site with the exception
of c;opper and iron. EP A used the WQCC ambient quality standard for copper and iron. The
28
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~
ambient level for copper is 30 ug/l based upon the 85th percentile ambient data in Segment 3a. '
The methodology used to develop these levels is similar to the criteria applied in the ,
, development of the NCt, that is, back modeling the contaminant loading from the promulgated
ARARs at the Alamosa River. These IAL are formally adopted as remedial goals in the IRODs.'
The discharge monitoring po~t, WF-5.5, is the interim monitoring point for the Site, and the
IAL are the interim water quality standards during this remedial action five year period. It is
important to note that the IALs are not "interim" due to their inability meet ARARs; rather, EP A
, believes that these ARAR-derived limits ~t the point of compliance do attain the numerical
standards at Segment 3b. The ability of the IAL to achieve the applicable water quality
, standards, however, will be reassessed by EPA upon the completion of the quantified Risk
Assessment and the State of Colorado use-attainability study. The results of these efforts will be
incorporated into a final remedy.
o
Federal Water Qu;ility Criteria, Applicable
The preamble to the proposed NCP states:
(a) State numerical WQS is essentially a site-specific adaptation of a Federal
Water Quality Criteria (FWQc), subject to EP A approval, and, when available, is
generally the approPriate standard for the specific body of water." (See 53 FR
51442, right column, top.) ,
As noted above, the FWQC would only be applicable in the absence of current, segment specific
, CWQS~ In this circumstance,'current, segment specific CWQS are available and will be applied
as the surface ~r quality ARARs for the Site. The FWQC are considered applicable 'since this
ARAR establishes the basis for the State of Colorado's numerical standards.
-
... ~ '.' . ~ '\ ..
. -.': ".
.c. ~......
, ,
.' ~ . . .-.
Ground Water ARA.Rs '
, The ColoIado Ground Water Standards (CGWSs) provide for identification of specified ground
water areas, classification of the specified areas, and numeric ground water q~ty standards.
, "
5 CCR 1002-8 establishes a system for classifyiUg ground ,water and adjusting water quality
standards to protect existing and potential'beneficial uses~ The ground water classifications are
applied to "specified areas," a concept identified in the definitions and explained in Section
3.11.4(C)(1). Those ground waters not classified as within "specified areas" may be subject to
Statewide radioactive material standards listed in Section 3.11.5(C)(2) of the Basic Standards of
Ground Water, 3.11.0 (5 CCR 1002-8) and organic standards identified in Table A of Section
3.11.5(C). ' .
, .
Since the Colorado Water Quality Commission (wQ9C) has yet to classify the Site as a
"specified area," there are no currently applicable or relevant and appropriate Colorado Ground
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~
Water numeric standards for the Site. However, since the publication of the Water Treatment
FFS, the WQCC has adopted an interim.natTative standard for all unclassified ground waters of
the State that supplements the Statewide standards for radioactive materials and org~c
pollutants established in Section 3.11.5(C) of the Basic Standards for Ground Water. This
narrative standard requires that ground water quality be maintained for each parameter at
whichever of the following levels is less restrictive:
(i) existing ambient water quality as of January ~ 1, 1994, or
(ii) that quality which meets the most stringent criteria set forth in Tables 1
through 4 of "The Basic Standards for Ground Water."
. Ambient water quality is established by agencies "with authority to implement this standard"
using "their best professional judgment as to what c;onstitutes adequate information to determine
or estimate existing ambient quality, taking into account the location, sampling date, and quality
- of all data available" prior to January 31, 1994. Based on Rule 1, Section 1.1(5) of the Mineral
Rules ~d Regulations, EP A believes the Mined Land Reclamation Board is the agency that has
the primaty authority to implement the natTative standard for ground water at the Summitville
Site. MLRB and WQCD established Numeric Criteria Levels (NCL) for surface and ground
. . water quality at the Summitville Site in SCMCrs operating pennit, as well as its 1991 Settlement
Agreement between SCMCI and the State. of Colorado. These NCL are not applicable or
relevant and appropriate, Since they are not legally binding, promulgated regulations. However,
these standards have been considered by EP A in establishing its interim- action levels for water
quality because they provide.useful information or recommended procedures in addressing the
interconnected. groun~ water and surface Water at the Site.
This interim ground water narrative standard, since it became effective on August 30, 1994, was
not identified ~ an ARAR in any of the FFSs for the Site. However, since compliance with this
ground water ARAR.will have little or no impact on the overall s~.ape~perfonnance or,cost orthe
alternatives evaluated, inclusion of this ARAR represents only a minor change to the.FFS ana . . .. .
Proposed Plan. ~ "Interim Final Guidance on Preparing Superfund Decision Documents,"
OSWER Directive 9355.3-02 (June 1989), at p. 5-3.
EPA further expects that once the CWQC completes its use attainability study and classifies Site.
ground water, the interim narrative ground water standard will be replaced by a "specified-area" .
classification or "site-specific" standard for the Site..This ground water ARAR will be attained
by the final remedial action(s) for the Site. . .
Storm Water Management and EjJ1uent Limitations A.RARs
Storm water management is governed by the storni water permitting requirements and the
Categorical Standards for Ore Mining and Dressing. Both the storm water permitting program
. and the categorical standards are as applied pursuant to the Colorado Discharge Permit System.
.
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"
Requirements are collection and treatment of storm waters using the .Best Available Technology
(BAT) for those storm waters which contact min~ waste. In additio~ both regulatory programs ,
reqwre implementation of Site-specific Best Management Practices (BMP). The BMP ,
emphasize storm water diversion and land/soil reclamation to m;nimi7.e the contact of storm'
water with mine wastes.
.
o
Copper, Lead, Zinc, Gold, Silver and Molybdenum Ores Subcategory Emuent
Limitations, Relevant and Appropriate
This ARAR applies to "process waste waters" only. Process waters are defined in 40 CFR
401.1l(q) as: ' '
"any waters which, during inanufacturing or processing, comes into direct contact
with or results from the production of any raw material, intermediate product,
finished product, by-product, or waste product." .'
The effluent limitations found in 40 CPR 440.103 would be appropriate and relevant to the'
Water Treatment FFS activities bUt not applicable because the discharges are not "process waste
waters." The IAL established by EP A to meet the surface water quality ARARs are more
sttingent than these categorical effluent lliiUtations.
, .
o
Colorado Discharge Permit System RegulationslFederalStorm Water Permitting,
Requirements '
Colorado's authority to require permits for the discharge of pollutants from any point source into
waters of the state are derived from the Federal National Pollutant Discharge Elimination System
(NPDES) regulations. See 40 E:FRPartlZ2.. Colorado!sNPDES'based'program:can,~e found'in '
the Colorado Discharge Permit System Regulations (CDPSR). The CWQCC Division Permit
. issued for the treatment plant at the Site (CDP #CO-0041947), dated November 12, 1991, is the
CDPSR document for the Site. Additional permit modification activities are documented in the
July 1991 Settlement Agreement and the July 1992 Amendment to the Settlement Agreement.
..
Storm water is defined in NPDES program 'as "storm water runoff: surface runoff, snow melt
runoff: and surface runoff and drainage". (See 40 CPR 12226(b )(13).) A permit application is
required for active and inactive mining sites where an owner can be identified and when'
discharges of storm water runoff from mining operations come into contact with any overbmd~ .
raw material, intermediate product, finished product, by product, waste product or areas where
tailing have been removed. (See 122.26(b)(14)(iii).) As such, the substantive NPDES Storm
, Water permit requirements are applicable to discemable surface flows of storm water that
contacts, waste roc:k. the crushed ore currently contained in'the heap leach " pads, wet waste rock
(mud), clay ore, or tailings at the Summitville Minesite. Infiltration is not covered by this
program. (See SS FR 47996, left column, center.) , " ".
..
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The storm water permit regulations require compliance with Sections 301 and 402 of the Clean
Water Act. Sections 301 and 402 require use of Best Available.Technology to control tOxic
pollutants, and where necessary, further control to achieve ambienfwater quality criteria. In
~dition, the storm water regulations require implementation of stormwater BMP as part of the ..
comprehensive program. '
EP A has established effluent limitation guidelines for storm water discharges ftom the Ore
Mining and Dressing category. These effluent limits require application of BAT to the Ore
Mining, and Dressing category. In.those regulations, EP A has defined "mine" broadly and in a
manner which coincides with the definition provided in the Storm Water Permit requirements.
(See 40 CFR 440. 132(g).) The effluent limitation guidelines for Ore Mining and Dressing also
provide an exemption for overflow of excess storm water caused by a greater than a 10 year 24 '
hour precipitation event when a facility has met certain design and operational prerequisites.
This exemption remains in effect as part of the new independent storm water permitting program.
(See SS FR 48032, right column, bottom.) .
.
, Both the effluent limits and the storm water permitting program' require application of BAT and,
if necessary, additional controls to meet ambient water quality standards. In addition, both.
programs require implementation of stormwater BMP. The only jurisdictional distinction is that
the Ore Mining and Dressing Category effluent limits are not applicable, but instead relevant and
appropriate. The recognition by the storm water permit program of the overflow exemption
demonstrates the existing equivalence of the programs. Thus, att~inment of the Effluent
Guidelines and Standards for Ore Mining and Dressing will ensure. att~inment of the storm water
discharge requirements. '
Eight outfalls were identified at the Summitville Minesite which meet the point source discharge
requirement for storm water permitting~ The discharge ftom each of these outfalls have been
attributed to one of the three categories of precipitation related discharges defined by the storm
waterregu1ations. (See 40. C-F:.~ 122.26(b)(13); SS Federal RegisteI:at.4&06S...,,, '- -. '
Pursuant to the NPDES Storm Water Permitting requirements anq. in response to obligations
. under the July 1, 1991 Settlement Agreement and Compliance Plan (the' Compliance Plan) for
Summitville Mine, a two volume BMP plan dated October 3.1, 1991 was developed. The
Compliarice Plan required that the BMP provide a reclanurtion plan and implementation schedule
that'included existing and planned pollution prevention practices. The BMP also evaluated the
need for long term treatment of storm water drainage at the facility. ' ' ,
The BMP was designed to minimi7.e or control contact between precipitation and potential
soUrces of pollutants. The BMP developed at the Summitville Minesite included housekeeping,
employee training, inspections, preventative maintenance. In addition, reclamation activities
such as grading, stabilization, revegetation" erosion control and sediment control were included
, as part of the BMP. Each of the measures was designed to protect the existing water quality and
quantity during the. operation phase and upon closure of the Summitville Mine.
.
32
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The existing B:MP plan which is currently being implemented at the Site and will continue to 'be
. implemented regardless of which alternative is selected, attains compliance with the NPDES . .
. stormwater and categerical point source standards.
. .. .
.
1.5.3.2
. Action Specific ARARs
Colorado MinedLand Reclamation Act
The Colorado Mined Land Reclamation (illR) regulations at 2 CCR 407-1 require the
reclamation of mined areas. The MLR regulations provide specific reclamation criteria which,
are applicable to the Summitville Minesite. As a previously disturbed area, at a minimum the
MLR regulations require reclamation to a pre-mining condition:
. .
The conditions imposed by the Colorado MLR Permit #M-84-157 for the Smnmitville Mine
stipulated a phased approach to land reclamation which minimizes the total. disturbed area at any
poiJ;lt in time. When mining activities in each area have ~een completed and the sections no
, longer are needed, the permit requires that all land associated with waste dumps, leach heaps,
roads, mine pits and plant facilities be reclaimed for forage and timber use. Pursuant to CRS 30-
20-102(4) a certificate of designation for solid waste disposal is not necessary for the Site
J>ecause the Site has been. issued Peimit #M-84-157. CRS 30-20-102(4) states:
" ...any person who is engaged in mining operations pursuant to a permit issued by the
mined land reclamation board or office of mined land reclamation which contains an ,
approved plan of reclamation may dispose of solid wastes generated by such operations
within the permitted area for such operations. For the purpose of this part 1, such solid
wastes disposal site and facility shall be an approved site for which obrnining a certificate
of designation under the Provisions of section 30-20-105 Shall be unnecesSary."
. " .. "..";'. . , ,':." . .' ,. ...
Reclamation 'activities at the Summitville MinesiteWillemphaSlZe surtaCe soifStabi!iZation' (to
include grading, top soil manageme~t, and revegetation), preservation of water quantity and
quality,' and concern for the safety and protection of wildlife.
Clean Air Act
..
. FederaI and state ARARs were identified for construction and generation ofp3rticulate matter '
(PMI0) at the Site. An emission penmt will be required if temporary construction activities
exceed more than two years (See 5 CCR 1001, ~3(I)(B)(3)(e).) Control measures to minimi7'e
dust and air monitoring will be implemented if necessary during remedial constIuction activities.
Regulation 1 of the Colorado Air Pollution Control Regulations requires all sources of particulate
emissions to utilize technically feasible and economically reasonable control measures. This
requirement is applicable to remedial activities that produce fugitive particulate emissions at the
Site.' .
33
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An air pollution permit was applied for at Summitville Minesite for the emission ofhy~gen
cyanide as a statiOIW}' source. The permit included a description of the cyanide leach heap pad
process at the Summitville Mine and all associated process chemistry. Permit # 92-RG-653 was
given an exempt status in September of 1992. The Summitville Site claimed uncontrolled
emissions of less ~" one ton per year and no emissions of hazardous, odorous or toxic
pollUtants and was therefore exempt (See 5 CCR Section 3(ll)(C)(l)G).) Thus, this particular
requirement is not applicable or relevant and appropriate at the Site." ".
RCRA Subtitle C
o
Identification and Listing of Hazardous Waste (40 CFR 261), Applicable
Water treatment procesSes will.generate potential residues from spent chemicals and.
sludges. These ~als will be managed in accordance with these ARARs.
o
Standards AppliCable to Generators of Hazardous Wastes (40 CFR 262), Applicable
Water treatment processes will generate potential residues from spent chemicals and "
sludges. These materials will be managed in accordance with these ARARs.
o
Standards Applicable to Transporters of Hazardous Wastes (40 CFR 263),
Applicable
Water treatment processes will generate potential residues from spent chemicals and
sludges. These materials will be managed in accordance with these ARARs, if sludges
. are transported off-site. . . "
o
Standards for Owners and Operators of Hazardous 'Yaste. Treatment, Storage and
Disposal Facllifies'(40CFR264),.AppliCabl~-"".......:..:-- .. ......"". . ~:. .. .
Water treatment processes will generate potential residues from spent chemicals and
" sludges. These materials will be managed in accordance with these ARARs. "
o
Hazardous ~teriaJs Transportation Act, D.O.T HSl7.9rdous Materials
Transportation Regulations (49 CFR 171-180), Applicable.
. . . .
Any process chemicals or sludges generated by water treatment operations transported
off-site will be transported in accordance with this ARAR.
.
.
34
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1.5.3.3
Location Specific ARARs,
Endangered Species
.
The Endangered Species Act requires that federal agencies'ensure that federal actions will not
jeopardize the continued existence of any threatened or endangered species or impact critical
habitat. In response, a Preliminary N~ Resource Survey will be performed to identify
natural resources, habitat types, endaD.gered or threatened species, and any potential adverse
effects or injury to trust resources.
Protection 01 Floodplains and Wetlands
Executive Order No. 11988 and Executive Order No. 11990 require federal agencies to evaluate
. the potential adverse effects of proposed actions: on Floodplains and Wetlands, respectively. '
Floodplains and wetlands potentially subject to adverse impacts from site remedial actions will
be inventoried and considered'during the analysis, selection and implementation of the remedy.
Clean Jf' ater Act - Dredge and Fill Requirements.
Section 404 of the Clean Water Act prohibits the discharge of dredged or fill material into
navigable waters, including wetlands. The Section 404 requirements are applicable if any
remedial action constrUction will involve dredge and fill activities.
,Fish and Wildlife Coordination Act
The Fish and Wildlife Coordination Act serves to protect fish and wildlife when federal actions
result in the control or'structutal modification,to.natural streams..or_water.bodies...Federal "
agencies must develop measures to prevent, Drltigate or compensate for projeci related losses of '
fish and wildlife. Specifically included are projects involving stream relocation and water
, diversion struetures. If applicable, prior to modification of water bodies, the applicable
regulations will be followed. ' , ,
'Colorado Wildlife Act
.
The act establishes the Colorado Wlldlife Commission, provides for wildlife TTulnaeement and
prohibits ac:tions detrimental to wildlife. The act is applicable if wildlife observed at the Site
would be adversely impacted by the implementation of the remedial action.
Wildlife Commission Regulations .
, '
Chapter 10 of the Colorado Wlldlife Commission regulations 92 CCR 406-8, Chapter 100 '
designates and protects certain endangered or threatened species. The regulations are applicable
, '
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~
if endangered or threatened species observed at the Site are adversely impacted by the
implementation of the remedial actiOIL .
Floodplain Management
The Executive Order on Floodplain Management (No. 11988) and 40 CPR g6.302(b) and
Appendix A requires federaI agencies to evaluate the potential effects of actions they may take in
a floodplain and to avoid, to the maximum extent possible, any adverse impacts associated with
direct and indirect development in a floodplain. This requirement may be applicable if the
remedial activities take place in a floodplain. .
Wetlands Protection
Executive Order on Protection ofWet1ands (No. 11990) and 40 CPR g6.302(b) and Appendix A
requires federal agencies to evaluate the potential effects of actions they may take in wetlands, in
. order to minimi7p- adverse impacts to wetlands. This requirement is applicable if the remedial
activities tak~ place in wetlands.
1.5.3.4
Guidance, Advisories or Criteria To-Be-Considered
. .
. Interim Guidance on Establishing Soil Lead Cle41ZUp Levels at Superfund Sites,
~M~~ ~ .
. Neither federal or state chemical specific ARARs for soil contamination were identified for
. contaminants. of concern at the Summitville Mine Site. A to-be-considered criteria was identified
. .
for soil lead contamination. Specifically, the "Interim Guidance on Estab]j~hine Soil Lead
Cleanup Levels at Superfund Sites", September 1989, (Directive #9355.4-02) will be considered
when :final remedial action objectives and goals are fIamed.
. . .
. .
. Amendment to 'fheSeitlement Ag,.eemenr ojiuiY'l; '}991;: ..consickr~d" .... . _:.
The Amended Settlement Agreement established the NCL under authorities from the Colorado
. Mined Land Reclamation Act ,sections 34-32-101 to 127, C.R.S. (1984 &1991 Supp.) and the
Colorado Water Qua!ityContn?1 Act, subsections 25-8-JOI to 703, C.R.S~ (1989). These.
- standards were believed to have been developed using a back calculation from segment 3b of the
Alamosa River. The NCL were considered during the technology and altemative screening and
analysis. .
1.6
Summary of Site Risks
The Human Health and Ecological Risk Assessment for the FFS was conducted using relevant
EPA guidance including the Risk Assessment Guidance for Superfund (EPA, 1989) and the
"
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RCRA Facility Investigation (RFI) Guidance (EP A, 1989). This risk ~sessment was a screening
level risk assessment intended to briefly examine risks associated with the HLP.
.l..6...l Screeiring Ecological Risk Assessment
A Screening Ecological Risk Assessment for the Summitville Minesite was prepared by EP A in
April, 1993. The screening ecological risk assessment reviewed the no action alternative to
determine if there is an imminent hazard to the Wightman Fork from the Site. Copper, zinc, and
cyanide were chosen as the COPC for the assessment.
The assessment modelled, measured, and predicted concentrations and the loading of copper in
Wightman Fork for three scenarios: ..
. . .
.
April 1993 conditions (included treatment ofHLP contained water and discharge
from the Reynolds Adit); .
.
Cessation of water treatment. activities; and
Catastrophic release of water contained in the HLP that could result from an event
such as a failure of Dike 1, the downgradient impoundment feature.
Effects of the contaminants on rainbow trout and brook trout were estimated by correlating acute
toxicity levels of the contaminants with measmed and predicted concentrations. The degree of
metals toxicity for aquatic life as affected by the pH and hardness of water was described. Study
results of copper concentrations that are toxic to trout at differing water hardnesses were included
. in the assessment to illustrate the variation of toxic copper concentrations with water hardness
(the sum of calcium and magnesium concentration expressed in terms of equivalent calcium
carbonate}. . '. . . .
. . .
... ,.' . ..... ..,...... . ".,'.
The screening ecological risk assessment recommended the following: .
.
..
.
Continuation of Site water treatment prior to discharge and reduction of metals
loading into the stream in order to achieve the Site's NPDES permit levels;
.
Reduction of the flow of contaminated ground water by plugging the adits for.
long-term meta1loading reductions to the Wigbtman Fork; .
.
Conducting an ecological survey of Wightman Fork to obtain Site specific
--information to document actual discharge impacts and document the recovery of
Wightman Fork after remediation; and
Completion of a baseline risk assessment because the review of the .no action'
alternative produced an unacceptable risk, defined as exceeding the Low
Observed Adverse Effect Level (LOAEL). . .
37
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The screening ecological risk assessment predicts an imminent hazard to the environment and '
suggests that all appropriate response actions should be undertaken to prevent the adverse effects
from continuing to take place. Water treatment is intended to prevent further environmental
degradation, and achieve significant risk reduction. '
, -
~ Environmental Risk Assessment
1.6.2.1
Aquatic Receptors
In general, ,the potential risks to aquatic organimts posed by an untreated ~lease from the French
Drain are predicted to be immediate and pronounced. COPC in the French Drain exceed acute
and chronic ,surface water goals by several orders of magnitude. Modelling predicts that
concentrations of cyanide discharging from Cropsy Creek remain acutely toxic until the
confluence of the Wightman Fork with the Alamosa River. Furthermore, the concentrations of '
cyanide would remain at levels in exceSs of the Colorado TVS in the Alamosa River for some'
distance below Wightman Fork. The TVS are promulgated, risk based standards developed to
protect aquatic life uses.
It is important to note thatthe Site's impact on pH alone may contribute t~ toxicity to aquatic
organisms, as there is a limited range of pH levels tolerated by aquatic receptors.
.Prior to treatment of the Chandler Adit, the Colorado TVS, ARARs in'Segment 3b of the
Alamosa River, were'regularly exceeded for copper, zinc, aluminum, iron and manganese. These
, exceedences are especially problematic as the hardness-dependent 'Colorado TVS may ,
underestimate the potential toxicity of metals in the acid drainage (low pH) environment below
the HLP. Normally, toxicity is reduced as hardness is increased. However, an undedying
assumption of the criteria is that alkalinity increases as hardness increases. This assumption'
holds for many natural waters" ho\ycver, at ijl~ S1lIIlID:itville Mine~ite hardness is re~vely high
, andal1caHn;ty is low. Ranges of data collected-by1hc,tJS6S in-l993' at Station'45:4-from"'" '
Segment 3b of the Alamosa River are as'follows:
Flow Season ' AnaJyte Maximum M= TIS
May-July Dissolved Copper 2600.00~ 1084.22~ 30",g/L
, - ,October-March Dissolved Copper 780.00",gIL 780.00",gIL '30 ",gIL
May-July, , Dissolved Zinc 4S0.00",gIL 301.44",gIL, ,230 ",gIL ,
October-March Dissolved Zinc ,437.00",gIL 437.00~ 230 ",gIL
The Colorado DiVision of Wlldlife, in comments on the proposed ambient water quality standard
for the Site, found that a self-maintaining population of brook trout was present in'the Alamosa
river segment that extends from the confluence of the South Fork of the Alamosa to Summitville
in 1987 (Colorado Division ofWlldlife, 1993). The population appears to have been el1minated
in the intervening years by contamination of the Alamosa River. '
38
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. .... ,': ",
, - '
. ., .'t." -"..
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. 1.6.2.2 -
Terrestrial Wildlife
.
An untreated release from the French Drain would pose significant risks to bird and mamm81
populations. Based on the modeled concentrations, risks to terrestrial wildlife from acute and
chronic exposures to cyanide would be high along Cropsy Creek and Wightman Fork. The
potential for chronic exposure is mitigated by the unsuitable habitats surrounding these sites.
The lack of suitable habitats makes regular use of these areas unlikely.
The other COPC that pose potential acute risks to bird and mammal species in Cropsy Creek,
include: cadmium, copper, and manganeSe. Risks from acute exposure in Wightman Fork are '
substantially lower, although the risks from chronic exposure in those areas with suitable habitat
(i.e., natural, undisturbed habitats) may be present. .
.LU Human Health Risk Assessment
. '
, A baseline human health risk assessment (HHRA) will characterize the risks posed by the COPC
at the Site. To evaluate current and future risks, EP A is planning to complete a quantitative
human health risk assessment in 1995. The assessment for human exposure to COPC proceeds
with the identification and characterization of likely expo~ scenarios, identification and
evaluation of exposure pathways, estimation of exposure concentrations, 'and quantification of ,
chemical intakes.
1.6.3.1
Exposure Scenario
The potential for exposure is bas~ on the existing Site conditions and poten~al ~ Site
conditions. Groups assessed for potential exposure pathways include on-site workers, on-site
residents, off-site residents,and,.intrudersltrespassers. "Presently;:,aceess.to~the.Site is being
controlled. Currently, on-site workers, trained under 6SHAHAZwOPER,are reqUired to'Use
personal protective equipment (PPE), and are routinely monitored;,therefore, they are evaluated
under a separate process. Since the Site is a historic mining district, on-site residents are not.
considered a viable exposed population currently or in the future. Off-site residents and potential
off-site recreational receptors.win require evaluation during a baseline ~ ~essment.
1.6.3.2
Exposure Pathways
..
An eXposure pathway describes the route a chemical may take from the source to the exposed
individual. A complete pathway consists of four elements: a source and mechanism of chemical
release to the environment, an environmental transport medium, a point of potential human
contact with contaminated medium, and an exposure route. The transport medium can be air,
ground water, soil, surface water, etc. The route can be inhalation ingestion or dermal contact
with the medium. '
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"
Evaluation of the potential pathways ~gests that most exposure pathways at the Site are .
incomplete. Currently, the only pathway with sufficient data for assessment.is surface water;
There is insufficient sampling data available to determine whether soil, ground water, and/or air
are exposure pathways. .
1.7
Description of Alternatives-
.
This section describes the alternatives retained for detailed analysis for this interim remedial
action. A description of all options considered for water treatment can be found in the ~
Treatment Focused FeasibilitY Study. Summitville Mine Superfund Site, Summitville, Colorado.
The five alternatives retained for detailed analysis to be discussed in this IROD are the .
following:' .
Alternative #1
Alternative #2
Alternative #3
Alternative #4
- Alternative #S
No Action;
Continue treatment of French Drain (FD) Sump and CWP
waterlI'reat HLP water;
Continue treatmentofFD Sump an~ CWP waterfI'reat HLP
water/Convert CDP and MRP to AMD treatmentITreat peak flow
AMD in MRP'
. ,
Continue treatment of FD Sump and CWP waterfI'reat HLP
, water/Convert CDP to AMD treatment! Shut down MRP/Use
containment for peak flow AMD control; and .
Continue treatment ofFD Sump and CWP waterfI'reat HLP
.~~o~.ne~_~ ~entp~t/Shut down CDP, MRP,
and CWTP.-. ... . . .. .. .
It should be noted that Alternative #2 through Alternative #S 'of the IROD correspond to .
Alternative #3 through Alternative #6 of the Water Treatment FFS, respectively. Alternative #2
in the FFS, Institutional Controls, was eliminSlted in the ~ process. For further
discussion of this alternative ai1d other treatment methods eHminSlted in the screening process,
refer to the Wau:r Treatment FFS. . .
. -_.
- -
. .
With the exception of the no action alternative, all of the alternatives are effective for removal of
. contaminSlnts from waters affected by Site conditions. All of the treatment alternatives include
utilization of technologies CU1'l'eIitly operating on-site and the continued use of existing treatment
facilities, except for Alternative #S, continued treatment with new plant.
. - . .., .
Alternative #3, 'continued treatment with AMD conversion, Alternative #4, continued treatment
40
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. - - ...---..- ..- ---_. - .-.. "
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"
with ANID conversion and containment, and Alternative #5, continued treatment with new plant,
include construction of an AMD collection and routing network. . .
- '
,"
Implementation of water treatment technologies will not interfere with current or future
remediation activities on-site.
. -~..
All of the alternatives, except the no action alternative, will reduce adverse effects on the
environment through treatment of AMD and water containing cyanide.
Institutional controls, such as posted warning signs and restricted Site access, are currently in
place on-site and will be maintained throughout remediation activities. .
- -
. - .-' .
. .
Removal of cont:lminants from solution will create a sludge rich in metal compounds. Sludge
will be disposed off-site by transport or contained and isolated on-site. Construction of a sludge
containment feature is included in Cropsy Phase n design. A study of metals remobilization by
sludge contact with acidic water is necessary. At this time, sludge presents no additional
concerns at the Site. ., . '
.l.1J. Alternative # 1
No Action
Inclusion of a no action alternative is consistent with th~ NCP and is required under CERCLA
and SAM. The pmpose of the 'no action alternative is to provide a baseline against which other
alternatives can be compared. The no action alternative is the cessation of current water
treatment activity and sediment control on the Site. Existing treatment infrastructure would be
, mothballed (mothballing is done to ensme reactivation without excessive expense for
replacement of equipment d:lm:lged by severe weather or other consequences of inactivity).
Ditches and ponds used to control surface runoff and sedim~t would not be maintained. Access, '
to the Site would not be restricted. -Monitoririg'tcrrecord and"evaluate-contamiuanuransport . "
effects on human health and the environment would continue. The capital costs for the no 8ction
, .alternative are $892,297. Th~ annual treatment and assessment costs are $55,640. The present
worth of annual ,treatment and assessment costs, based on 5 years at a 5% interest rate, are '
$240,892. The total capital and present value of annual treatment ,and assessment costs is
$1,133,189. . . ' . . - ., ..' .
.L1.Z Alternative #2
- - Continue treatment of French Drain SUl1'P and CWP Water! Treat
HLP water .' ,
Alternative #2 includes continued treatment of AMD water discharging from the Cropsy Waste
Pile and treatment of French Drain Sump water in the CWTP. HLP water would be treated by
the CDP/MRP as part of the HLP remediation. After completing cyanide treatment of water
from the HLP, the CDP and MRP treatment plants would be shut down and mothballed.
Treatment of CWP and French Drain water at the CWTP would continue until water quality in
$e associated streams meets remedial objectives. The capital costs for this alternatiye are
-------
"
$9,936,915. The annual treatment and assessment costs for 1995-:-99 are $55,640. The present
worth of ann~ treatment and assessment costs, based on 4 years at a 5% interest rate, are
$187,902. The total capital and present value of annual treatment and assessment costs are
$10,123,8.07. .
..
'.l..U Alternative #3
Continue treatment of French Drain SUII1P and CWP water/ Treat
HLP water/Convert CDP and MRP to AMD treatment rrreat peal&
flow AMD in MRP. .
~
Alternative #3 includes continued treatment of AMD water discharging,from the'CropSy Waste
Pile and treatment of French Drain Sump water in the CWTP. HLP water would be treated by
the CDP/MRP as part ofth~ HLP remediation. Treatment ofCWP and French Drain water at the
CWTP would continue until water quality in the associated streams meets with remedial .
objectives. After completing cyanide destruction of the HLP, the CDP and MRP treatment
plants would be converted to treat AMD. The converted CDP would treat AMD, minimi7ine
contaminant transport to the degree possible by its capacity, 500 gallons per minute (gpm). The
MRP would .shut down during the months when Site AMD volume can be treated by the CDP.
The MRP would be recommissioned during peak flow periods (May - July) to treat con1J:lminated
water volume in excess' of CDP capacity. Utilization of the MRP adds 400 gPm to the total
treatment capacity. The capital costs for this alternative are $9,795,483. The annual treatm~t
and assessment costs are $9,488,451 for 1995-96 and $6,398,767 for 1996-97. The present
worth of annual of annual treatment an4 assessment co~, based on 4 years at a 5% interest rate,
are $24,411,683. The total capital and present value of annual treatment and assessment costs are
$32,207,166. ,
, ~ Alternative #4
Continue treatment of French Dnrin Sump and CWP water/ Treat
HLP water/ Convert CDP to AMD treatment! Shut down MRP/
Use containment for peak flow AMD control.
'. . ',' .'.... ". ".l"' ~-. .. . ~. .'; r.. '. " - .."
..' " '.
. .
Alternative #4 includes continued treatment of AMD water discharging from the Cropsy Waste .
, Pile and treatment of French Drain Sump water in the CWTP,. HLP water would be treated by
the CDP/MRP as part of the 'HLP remediation. Treatment of CWP and French Drain water in the
CWTP would continue until untreated water quality in the associated streams meets' with
remedial objectives. After completing cyanide destruction of the HLP, the CDP would be
.' 'converted'to treatment of AMD. The MRP would be shut down. During peak flow periods
(May - July), contaminated water volume in excess of the converted CDP capacity would be
contained to allow treatment in the CDP when possible. A containment structure(s) would be
utilized or constn1eted which would constitute a surface impoundment(s) for runoff control of
AMD waste. The location and capacity of the containment structure is discussed in ApPendix D
of the Water Treatment FFS. This waste would be stored for treatment at the existing CDP
facility. Exact volumes and waste types would be dependent upon selected storage areas at the
Site ana amount of cyclical nmof[ The. capital costs for this alternative are $9,785,483. The
annual treatment and assessment costs are $8,924,135 for 1995-96, $3,927,035 for 1996-97, ,
42
.- ....
. ~ ..::-. ....
-III' ,.- .
"""~",,..--" ,...:'".. -.
-- - _.,--
. ... r".--.r'-"-
-------
"
$2,917,226 for 1997-98, and $2,901,618 for 1998-99. The present worth of annual treatment and
assessment .costs, based on 4 years at a 5% interest rate, are $15,469,208. The total capital and
present yaIue'ofannual treatment and assessment costs are $26,874,691. .
.1...U Alternative #5
. Continue tteatment of French Drain SUII\P and CWP water! Treat
HLP water! Construct new AMD treatment plant !Shut down the
CDP. MRP. and CWTP
..
Alternative #5 includes continued treatment of AMD water'discharging from the Cropsy Waste
Pile and treatment of French Drain Sump water in the CWTP. HLP water would be treated by
the CDPnv1RP as part of the HLP remediation. When cyanide destruction is no longer needed,
the CDP, :MRP and CWTP would be shut down. During the HLP remediation period, a new
water treatment plant would be constructed. The plant would be designed to treat all selected
AMD'streams, in accordance with Site remedial action objectives. All AMD would be treated in
. the new plant. The capital costs for this alternative are $15,024,521. The annual treatment and
. assessment costs for 1995 are $5,834,452 and for' each year following, the costs are 4,795,284.
The present worth of annual treatment and assessment costs, based on 4 years at a 5% interest
rate, are $17,136,689. The total capital and present value of annual treatment and assessment
costs are $32,161,210. . . . .
1.8
. Comparative Analysis of Alternatives
. Provisions of the NCP require that a limited number of alternatives that represent viable.
alternatives be evaluated against nine criteria in 40 CFR 300.430(e) (9). The alternatives are
. evaluated against eaCh of these criteria and then agaiIist each other to determine the preferred
alternative. Table 9 presents a summary of this analysis.
. . .
.. ~ . ..'. .
. ~., . ...-.. -. - . P' . .
. ',4' ",' ,. .
.1..tl Cnteria I:
Overall Protection of Human Health and the Envirotpnent
The overall protection of human health and the environment criteria addresses whether or not the
interim remedial action provides adequate protection and describes how risks .posed through
exposme pathways are e1imin~tp.d, reduced, or controlled.' .' .'
. . .." .'
Alternative #1, the no action alternative, "does not alleviate the threat to the environment. No'
action is the least effective alternative for protection of human health and the environment during
interim remedial actions. .'
Alternative #2, continued treatment With no AMD conversion, allows continued metals loading
to downstream waters, sustaining unacceptable risk to aquatic receptors. Risk to human health
would continue at its present level until water quality improvements are complete. This.
alternative offers more protection than the no action alternative, but less protection than all other
alternatives.
-------
",
Alternative #3, continued treatment with AMD conversio~ improves overall protection of
human health and the environment through treatment of additional AMD after cyanide
destruction is complete. Activation of the MRP during peak flow periods preserves this overall
protection; bowever, without adding storage capacity or plant facilities release of contaminated ,
water in excess on peak capacities is required while HLP water is being treated. Ground water
and n,on-point source water continue to be potential contaminant contributorS.
Altemative #3, continued treatment with AMD conversion, provides significantly'more
contaminant removal than Alternative #1, no action, and Alternative #2, continued treatment
with no AMD conversion, but less than Alternative #4, continued treatment with AMD '
conversion and containment, and Alternative #5, continued treatment with a new plant Peak
flow in excess of 1,000 gpmwould discharge untreated into Wightman Fork.
to
Alternative #4, continued treatment with AMD conversion and containment, improves the
, overall protection of human health and ~e environment through treatment of additional AMD
after cyanide destruction is complete. Containment of surface water assures the maximum
, possible protection during interim remedial actions. Ground water and non-point source waters
would continue to be contaminant contributors until'identified and routed to treatment, if
necessary.
. ,
Alternative #4, continued treatment with AMD conversion and containment, provides greater
contaminant attenuation than Alternative # 1, no action, Alternative #2" continued treatment with
no AMD conversion, and Alternative #3, continued treatment with AMD conversion, and
approximately the same amount as Alternative #5, continued treatment with a new plant
Alternative #5, continued treatment .with new plant, provides overall proteCtion of human health
and the environment through treatment of surface water. This alternative provides the same
degree of protection as Alternative #4, continued treatment with AMD conversion and
containment r. ,', ' " ,,,", "'.. ,.
ll2 Criteria 2:
Coq,liance ~th ARARs
Alternative #1, no action does not attain the chemical specific ambient water quality ARAR
identified for Segment 3b of the Alamosa River. Alone, none of the alternatives will attain the
chemical specific ambient water quality ARAR identified for Segment 3b of the Alamosa River.
In conjunction with the other interim remedial actions, EP A has determined that only
Alternatives 4 and 5 will attain the surfaCe water quality ARARs at the point of compliance,
Wightman Fork 5.5 (WF-5.5). Specifically, analysis within the Water Treatment FFS identified
Alternative 3 as attaining the water quality ARAR 90% of the time based upon existing Site data.
The reJ1'1aining 10% represents untreated runoff from spring flow in 1995 without construction
of the storage reservoir. Upon construction of the impoundment in the selected remedy,
Alternative 4, EP A has assumed 100% compliance with the water quality ARAR at the point of
compliance, WF-5.5. The attainment of this ARAR can be achieved through eftluent qWility at
44
,?
. -,
. ,
.,"--,
. .'. .".~"-" .
-------
.... .--....-.---
....-'....--.
~ .'
I'
the point of discharge into the Wightman Fork. Because only clean upgradient water will be
entering WightmaIi Fork prior to the water treatment effluent point, discharging effiuent that
meets the IAL should meet ARARs at the point of compliance. Additionally, the only discharge
period from the plant would occur during high flow conditions; thus, there would be no .
degradation of water quality expected in the Wightman Fork due to the remedy. Additional water .
quality controls would be available through treatment of the Valley Center Drain and Cropsy
Waste Pile runoff through the Cropsy Wastewater Treatment Plant, ifrequired. The final
treatment alternative was evaluated as to attainment of these standards based upon alternative
development The development of Alternative 5 envisioned the construction of a new waste
water treatment plant "designed to treat all selected AMD streams, in accordance with Site
remedial action objectives" (pg.64, Water Treatment FFS). By definition, this alternative would
meet ARARs through deSigned treatment capacity. ..
All alternatives implement acceptable BMP for effiuent limitations and stormwater management
.. .
All alternatives will attain the ~R reclamation requirements. . .
All alternatives will meet fugitive particulate emissions ARARs during implementation. The
ARAR will be attained through technically feasible and economically reasonable control
measures. .
All alternatives will meet the action-specific RCRA Subtitle CARARs."
All alternatives Will attain all ~ocation-specific ARARs.
lJ..l Criteria 3:
Loni-tenn Effectiveness and Pennanence
. Long-=term effectiveness and permanencerefersJo~the~ty..Qf.ar.eniedY to'.piOYide.reliable. . ,.,
protection of human health and ~e environment over time. . According to 40 CPR
300.430(e)(9)(iii)(C), factors that should be considered in assessing the long-term effectiveness
and permanence of a remedy include the magnitude of residual risk remaining from untreated
waste or treatment residuals reJTlaining at the conclusion of remedial activities; and the adequacy
and reliability of controls such as containment systems and institutional controls that are
necessary to manage treatment residuals and untreated waste. .
It is anticipated that in the short-term., water treatment will be needed to meet water quality
criteria. However, in the long-term., water treatment may not be needed due to the success of
other remedial activities on-site. An evaluation will be performed in five years after this interim
action is completed to assess the continued need for water treatment and the level of treatment
required.'
. . .
. The no action alternative, Altemanve # 1, would not be successful in meeting any established
RAOs or focused water treatment goals. The residuals would continue to severely impact the -
-------
fl.
water quality on-Site and downstream from the Site. The no action controls at the' Site are
ineffective at containing contaminants. No action is the least effective alternative for preventing
potential long-term effects of contaminants on downstream aquatic, agricultural, and domestic
~~~. .
Alternative #2, continued treatment with no AMD conversion, provides adequate cot1rnimnent
and isolation of residual sludges produced by the operation of the treatment plants. Use of a
properly designed and constructed disposal area is necessary. Proper maintenance of
containment and capping of sludge as a final action will prevent metals remobilization through
sludge contact with acidic waters. There may be additional measures that provide stability for
sludge constiwents. Since this alternative treatS the least amount of water, it would leave the
least amount of waste to be properly stabilized. The long-term effectiveness of Alternative #2
'is greater than Alternative.#I, no action, but less effective than all other alternatives.
~
Alternative #3, continued treatment with AMD conversion, provides adequate contairiment and
isolation of residual sludges produced by the operation of the treatment plants. Use of a properly
designed and constructed disposal area is necessary. Proper maintenance of the containment and
the capping of sludge as a final action will prevent remobilization of metals by sludge contact
with acidic waters. There. may be additional measures that provide stability for sludge
constituents. This alternative provides more permanent benefits than Alternatives # 1, no action,
and Alternative #2, continued treatment with no AMD conversion, but less permanent benefits
than Alternative #4, continued treatment with AMD conversion and co.ntainment, and Alternative
#5, continued treatment with a new plant.
. .
Alternative #4, continued treatment with AMD conversion and containment, and Alternative #5,
continued treatment with a new plant, provide the same degree of long-term protection of human
health and the environment. Treatment of all AMD streams may result in greater residual sludge
volume than provided by Alternative #1, no action, Alternative #2, continued treatment with no .
AMD conversion, ~4,Alternati:v.e :#3, . continued treatmeDt WithAMD.con.vemon., .. .. . '.
. .., "'" .. . . . . ..,'..',;..r. .;-.. .. . .. .
~ Criteria 4:
Reduction of ToxicitY- MobilitY- and Vo~uih Treatment.
Reduction of toxicity, mobility, or vol~e through treatment refers to the preference for a
remedy that reduces health hazards, the movement of contaminants, or the quantity of
contaminaf\ts at the Site. . .
. . . . .
Treatment is not a component of Alternative #1, the no action alternative. . There would not be a
reduction of transported contaminant load to downstream waters or a reduction in the quantity of
contaminants. '.'
. .
Alternative #2, continued treatment with no AMD conversion, reduces the volume of transported
contaminants through water treatment. Metals mobility in residual materials is low. Risks to the
environment by the on-site disposal of sludges can be minimi7ed ?y the.proper conStruction and
46
-
.. . " . . .
. ',:.- -4 ... -.9 "
," ,J',- ......-...--... " '
. .. 9,
. .' :':'.'.;'
-------
." "_.'''''''-;''.'
, .
-'~""'--"';''\-. "'-"" ....' -...,.... -,_.,
., . ... -~.
_.. .. .""~~-, .
"
maintenance of containmentf1s01ation features. Further study on sludge stability is needed. This
alternative is the least effective treatment alternative for reducing total contaminant toxicity,
inobility and volume. '
.
Alternative #3, continued treatment with AMD conversion, reduces the volume of transported
contaminants through water treatment. Metals mobilitY in residual materials is low. Risks posed
to the environment by the on-site disposal of sludges can be minimi7.ed by the proper
construction and maintenance of isolation and containment features and/or sludge ~ility
enhancement. Recycling of some sludges may be practicable. . .
Alternative #3,' continued b:eatm~t with AMD conversion,' ~ould ~harge-Peak AMD flow in
excess of 1,OOO.gpm untreated into Wightman Fork. Therefore, this alternative is more effective
~ treatment Alternative #2, continued treatment with no AMD conversion, but less effective in
reducing transported metals load than Alteniative #4, continued treatment with AMD conversion
and containment, and Alternative #5, continued treatment with a new plant. .
. .
. .
Alternative #4, continued treatment with AMD conversion and containment, and Alternative #5,
continued treatment with a new plant, provide treatment of all contaminated point source
discharges. The volume pftransported contaminants is reduced through water treatment. Metals
mobility in residual materials is low. These alternatives provide the same degree of contaminant
removal. Alternative #4, continued treatment with AMD conversion and containment, and
Alternative #5, continued treatment with a new plant, are more effective at reducing the
movement of contaminants and the quantity of contaminants tbaIi all other alternatives.
. .
.LU Criteria 5:
Short-tenn Effectiveness
Short-term effectiveness ad~sses file period of time needed to complete the remedy, and any
adverse effects to human health and the environmenitbat.may..becaused duringthe"canstruction_.. "
. and implementation of the remedy.
Due to the remote location of the Site and the exiSting access restriction, 0:0 substantial risks to
local communities or populations are anticipated by implementation o( any of the alternatives.
All alternatives pose the same primary risks to personnel working at the Site as those that
currently exist. Measures implemented to mi~im;7.e these risks are contained in the Site H~th
and Safety.Plan. .' -~-" .,. .. .' .
Alternative #1, no action, adversely impacts water quality by the cessation of all treatment
activities at the Site and the release ofwaste streamS into the HLP. Large volumes of
contaminants would migrate off-Site creating increased metal loading and reduction of pH in the
drainage pathways. No action is the least effective alternative for redu.cing risk at or downstream
from the Site. . . " -_. - . . .. .
.'
.' .. . . .. - . -~. "
. There would be no significant additional impact to human health and the environment during
-------
"
implementation of Alternative #2, continued treatment with no A1vID conversion. The short-
term effectiveness of Alternative #2, continued treatment with no A1vID conversion, is slightly
higher than the effectiveness of Alternative #1, no action. However, when compared to the other
alteInatiyes, this alternative is the least effective, because AMD is not treated or contained.
. There would not be significant additional impact to human health and the environment during
implementation of Alternative #3, continued treatment with AMD conversion. Environmental
impacts of Alternative #3, continued treatment with AMD conversion, caused by construction of
a solution collection and routing system are considered to.be minimal. This alternative is more
effective in the short term than Alternative # 1, no action and Alternative #2; continued treatment
with no AMD conversion, but less effective than Alternative #4, continUed treatment with AMD
conversion and containment, and Alternative #5, continued treatment with a new plant
,
Alternative #4, continued treatment with AMD conversion and containment, provides an
immediate benefit through containment and treatment of all point sources of AMD. Metals
removed would not degrade waters downstream from the Site. Environmental impaCts, caused .
by construction of a solution collection and routing system, are considered to be minimal. The
effects from potential constniction of a containment feature would also not be significant This
alternative provides .greater short-term effectiveness than any other alternative, but approximately
the same amount as Alternative #5, continued treatment with a new plant. .
Alternative #5, continued treatment with new plant, provides immediate benefits through the
treatment of all point sources of AMD because ituti1iZes the existing treatment capabilities while
. the new plant is being constructed. Metals removed would not degrade water downstream from
the Site.. EnvironmentSl impacts for Alternative #5, continued treatment with new plant, caused
. by construction of -a new water treatment plant are considered to be minimal. 1bis alternative.
provides the same short-term effectiveness as Alternative #4, continued treatment with AMD
conversion and containment. . '.
... ~..
. ~; ". "'.;' ". "
. 1"' I' .- - ..-
~ . '. . . .. .
.l...U Criteria 6:
III\PlementabiUtt
lniplementability refers to the technical and administrative feasibility of a remedy ~ . This includes
the availability of materials and services to carry out a remedy. It also includes coordination of
. Federal, State, and Local government efforts to remediate the Site. .
Implementation of Alternative #1, the no action alternative, offers no implementability concerns
since it is technically and administratively feasible. .
. .
Implementation of Alternative #2, continued treatment with no AMD conversion, involves only'
on-site activities; therefore, no additional administrative approvals or permits will be required.
Materials. and services required for implementation either presently eXist or are readily available.
Shutdown and mothballing of the CDP and MRP require conventional winterization measures.
Alternative #2, continued treatinent with no AMD conversion, is the easiest alternative to
48
';.-... '''-:''''~
.. ~ " --=-""'" ".--
. ..-
. - .- .. .
.,- ..... .. -..'- . .
-------
---.....
-----. -~._-_.-
. . .. .
"
implement because all the required facilities are currently in use.
. Implementation of Alternative #3, continued .treatment with AMD conversion, involves only:on-
site activities. Therefore, no additional8.dministrative approvals or permits will b~ required.
Materials and services required for implementation either exist or are available. Shutdown and
mothballing of the MRP requires conventional winterization measures. .
.
Since the CDP and MRP would be converted to treat AMD during peak flow, the
implementability would be more difficult than Alternative #1, no action, and Alternative #2,
continued treatment with no AMD conversion, but less difficult than Alternative #4, continued
treatment with AMD conversion and containment, and Alternative #5, continued treatment with a
new plant.' .
Alternative #4, continued treatment with AMD conversion and containment, is implementable.
Selection of the area in which excess. AMD. is to be contained affects ease and timing of
implementation. Implementation involves only on-site activities; therefore, no additional
. administrative approvals or permits will be required. Materials and services required for
implemeritation either presently exist or are readily av2nable.
Implementability of this alternative would be more difficult than Alternative #1, no action,
Alternative #2, continued treatment with no AMD conversion, and Alternative #3, continued'
treatment with AMD conversion, but not as diffiCult as Alternative #5,' continued treatment ~th
a new plant.
Alternative #5, continued treatment with a new plant, is implementable. Location of a new plant
will be affected by other remedial actions. Implementation involves 'only on-site activities;
. therefore, no additional administrative approvals or permits will be required. Materials and .
services required for implementation 'either presently' exist~or are readily available. .Alternative. .. ,
#5, continued treatment with a new plant, is the'most difficult alternative to implement since it
, requires building a new plant.
1...t1 Criteria 7:
~
Cost evaluates the estimated capital, treatment and assessment costs of each alternative in
comparison to other equally protective alternatives. . .
Alternative #1, no action, is the least expensive alternative, bUt it is also the least effective.
Capitol costs associated With this option include shutting down and closing the Site water
treatment plants, Site support, and demobilization of equipment. Annual treatment and
assessment costs directly associated with implementing this alternative include monitoring
contaminant effects. Monitoring costs associated with downstream pollution mitigation and/or
supplemental soil additives in agricultural impact areas cannot be estimated at this time. The
cost detail is shown in Table 10. .
49
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"
Estim9tes of expected costs are:
Capital Costs:
$892,297
$55,640
~~
Annual Treatment and Assessment Costs:
Present Worth of Annual Monitoring Costs:
$240,892
~
r otal Capital and present value monitoring costs:
S1,133,189
(Present Worth cost for 5 years at 5% interest rate.)
Capital costs for Alternative' #2, continued treatment with no AMD conversion, include draining
of the HLP, shutdown of the CDP and l\1RP, Site support,.and equipment demobilization.
Assessment costs include .monitoring of contamination after 1994. The cost detail is shown in
Table 1 L
Alternative #2, continued treatment with.no AMD conversion, costs more than the no action
alternative and less than the other retained alternatives.
.Estimates of expected costs are:
Capital Costs:
$9,936,915
Annual Treatment and Assessment Costs:
1995-99
$55,640 .
~ Present Worth of Annual~tmentand assessment Costs:..S181,9.02... ,.,-
. ". " .'.
. Total Capital and present value of treatment and
assessment costs:
SI0,123,817
(Present Worth cost for 4. years at 5% interest rate.)
Capital costs for Alternative #3, continued treatment with AMD conversion, include .-:- .
expenditures for HLP leachate treatment, Site support, :MRP shutdown, and equipment
demobilization. Annual treatment and assessment costs include AMD treatment, .
reactivation/shutdown of the l\1RP and Site support. The cost detail is shown in Table 12.
. .
This is the most costly alternative, evaluated.
Estimates of expected costs are:
50
.~ . .
. .,;... -~.:.:.;... .'";'1.;" _:;~. '.'
-
'. :.. -.."- . .
-------
.--.-.--
.~~...._.~. ._~-
.. .. -"...". --... --~
fl.
o
Capital Costs:
$9,795,483
Annual Treatment and Assessment Costs:
~
1995-96
1996-97
$9,488,451
$6,398,767
.
Present Worth of Annual treatment and assessment Costs: $24,411,683
Total Capital and present value of treatment and
. . assessment costs:
$32,207,166
(Present Worth cost for 4 years at 5% interest rate.)
Capital costs for Alternative #4, continued treatment with AMD conversion and containment,
inciude expenditures for HLP leachate treatment, Site support, MRP shutdown, rerouting of
effluent, and equipment demobilization. The annual treatment and assessment cost estimate is
for AMD treatment and Site support. Costs anticipate polluted water volume reduction resulting
from other remedial actions. The cost detail is shown in Table 13.
. The cost of this alternative is greater than Alternative #1, no action, and Alternative #2,
continue~ treatment with no AMD conversion. The cost of Alternative #4 is significantly less .
than Alternative #3, because the containment structures reduce the cost of water treatment by
eliminating the need for water .treatment during the winter months and .by treating at capacity
during high flow (which is mo~ cost effective). The cost of Alternative #4 is also significantly
less than the cost of building a new treatment plant (Alte~ve #5). .
Estimates of expected costs are:
,~,' , ~
,'. -. ." .,
'." . ' ~
Capital Co~:
$9,785,483
$1,610,000
Capital cost for constructed storage/containment
Annual Treatment and Assessment Costs:
1995-96
1996-97
1997-98
1998-99
$8,924,135 -
'$3,927,035
$2,917,226
$2,019,618
Present Worth of Annual Treatment and
Assessment Costs: .
$15,469,208
. .
Total Capital and present value of treatment and
assessment Costs with constructed storage option:.
$26,874,691
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fl.
o
(Pre~ent Worth cost for 4 years at 5% interest rate.)
. Capital costs for Alternative #5, continued treatment with a new plant, include HLP leachate
tieatment, Site support, shutdown of existing plants and demobilization. Annual treatment and
assessment cost estimate is for water treatment and Site support. The cost detail js shown in
Table 14.
~
. .
Costs are comparable to the costs of Alternative #3, continued treatment with AMD conversion,
but greater than all other alternatives.
Estimates of expected costs are:
Capital Costs:
$15,024,521
Annual Treatment and Assessment Costs:
1995
1996-99 (ea.)
$5,834,452
$4,795,284
. .
Present Worth of Annual Treatment and
Assessment Costs:
$17,136,689 .
Total Capital and present value of treatment
and assessment costs:
$32,161,210
(Present Worth cost for 4 years at 5% interest rate.)
.LU Criteria 8": . StateAcc~tance_... .......-.'
State acceptance describes whether the State agrees with, opposes, or has no comment on the
preferred alternative. .
The State concurs in the selection of Alternative #4, as the interim remedial action.
Ua2 Criteria 9:
Community Acc~ce
Community acceptance includes determining which components of the alternatives interested
people in the community support, have reservations about, or oppose.
The community concerns regartiing water treatment include the lack of significant water
treatment until 1996, concerns that the water quality standards in Wightman Fork and Alamosa
. River may not be met, the disposal of the residual sludge, and statutory compliance with ARARs.
52
-.
. .
'-7''''." :---..
,..--,...
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,
The community responses to the alternatives ale presented in the Re.sponsiveness Snmmary,
S~tion 3.0. The Responsiveness Snmmary addresses comments received during the public
comment period.
.'
1.9
.
The Selected Alternative
Based on the comparative analysis of the nine criteria, Alternative #4 (continued treatment with .
AMD conversion and containment) is the selected remedy for the water treatment interim.
. remedial action. '
The major components of the selected interim alternative include:
.
Continued treatment of the CWP drainage and the French Drain waters in the
CvrrP. '
.
Destruction of cyanide in the ~ from the HLP will continue in the CDPIMRP
until the water quality meets remedial action objectives. ' '
.
Completion ofHLP remediation, followed by the converSion oftheCDP to treat'
AMD. The MRP would be closed and would remain on-Site as a contingency
facility :
.
Containment ~f AMD in the area of the SDIIBMD during peak surface water '
floWs that exceed CDP capacity (500 gallons per minute). The contained water
would be treated before being released into Wightman Fork during Interim
Remedial Action. '
, "
.. .. . ." .. . _. .-.,.. .,........~ ,...", .,." .' . . -. .. . ." .~.. '.' ,'.,. ... ., - . . .
Implementing this interim remedial action will achieve protection of human health and the
, environment. The RAOs and goals for this interim action are: '
.
Compatibility with sitewide RAOs;
.
Reduction of contaminated water impacts to the aquatic receptors in the
Wightman Fork, the Alamosa River, and the Terrace Reservoir during interim
remedial activities;
.
Flexibility in the treat1Ilentof varied volumes and chemical makeup of the water
requiring treatment;
.
Minimi~tion of water treatment costs;
.
. . . .
Minimi~tion of treatment waste products and waste disposal requirements; and
53
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"
.
Realization of practical resource recovery to lower overall treatment and Site
remediation costs.' ,
Alternative #4 was chosen as the selected remedy based on the following:
.
This alternative provides overall protection of human health and the environment.
.
This alternative may not initially attain ARARs, but is eligible for an ARARs
waiver because it does not exacerbate Site problems and is consistent with the
expected sitewide' final remediation goals. ARARS will be met with final ' .
remedial action(s) for the Site. '
.
.
This alternative provides long-term effectiveness by reducing the contaminant
load to downstream waters. '
.
This alternative reduces the volume and mobility ,of transported contamin~nts and
metals through water treatment.
.
, This alternative provides immediate short term benefits through contaiJiment and
treatment of all point sources of AMD. By implementing this alternative, ,
Wightman Fork would nOJ be degraded by the release of contaminated water
during seasonal peak flows.
.
This alternative is easily implemented because it involves only on-Site activities.
Additional technical or administrative permits are not required. ,
.
This alternative is the least expensive alternative relative to the benefits it
provides.
~ . ..-.
This interIm ~edy is consistent with cmrent or futme aCtivities to complete sitewide
, remediation goals. '
1.10
Statutory Determinations
The selected remedy meets the statutory requirements of Section 121 of CERCLA as amended
by SARA. These statutory requirements include protection of human health and the
environment, compliance with ARARs, cost effectiveness, utilization of permanent solutions and
alternative treatment technologies to the maximum extent practicable, and preference for
treatment as a principal element. The manner in which these requirements are met uti1i7ing the
selected remedy is presented in the following discussion.
S4
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- .--.'-M-.'~-MM'-'.~
"
.:
1.10.1 Protection of Human Health and the Environment
, ' ,
'This interim action protects human health and the environment from the threat being addressed
and the contaminated water being treated.
.
This remedy includes the use of on-site containment of AMD flows that may exceed the
treatment capabilities of the plants during the spring runoff. Constructed storage capacity in the
area of the SDI/BMD will be utilized to control the untreated discharge of AMD int~ Wightman
Fork during these peak flow periods. ' '
Implementation of this remedy allows maximum reduction of surface water pollutant mobility'
, and volume. Peak flow containment optimizes seasonal water management and these
containment features may be used for long term attenuation of metals loading.
1.10.2 Conwliance With ARARs
Under Section 121 (d)(1) QfCERCLA, remedial actions must attain standards, requirements,
limitationS, or criteria that are applicable or "relevant and appropriate" under the' circumstances
~f the release at the Site. This action will attain the IALs in effluent discharged upstream of the
compliance point WF-5.5. Dependent upon stream flow and quality, this remedy will meet IALs
at WF-5.5 and attain ARARs.at monitoring point AR-45.4. This remedy will satisfy the ARAR
requiring application ofBlvfP to stoIIIlwater, and similarly will attain Mine Land Reclamation
(MLR) reclamation requirements.
1.10.3 Cost Effectiveness
, The selected remedy is. cost-effective because it has been determined to provide overall
effectiveness proportional to, its costs, the net presentworth~value being$26;814;69L ..Treatment~ .
of AMD is. a proven technology in the protection of human health and the environment.
1.10.4 Utilization of Permanent Solutions. ancl.Altemative Treatment TechnoloiPes or Resource
Recovexy Technolo~es to the MaXimum Extent Practicable (MEP)
It has been determined that the selected remedy represents the maximum extent to which
permanent solutions and treatment technologies can be utilized in a cost...effective manner to
address the control of AMD at the Summitville Site. Of those alternatives that are protective of
human health and the environment and comply with ARARs, itwas determined that the selected
remedy provides the best balance of trade-offs. in terms of long-term effectiveness, reduction in
mobility, or volume achieved through treatment, shott-term effecnveness, implementability, and
cost, while also considering the statutory preference for treatment as a principal element and
considering state and community acceptance.
The selected remedy treats the principal threats posed by the possibility of AMD entering the
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~
surface water system. Water quality drainage from the Site is expected to improve as interim .
remedial actions are completed. This improvement, along with removal of cYanide and metalS
from water contained in the HLP, will result in decreased pollutant content in water feeding the
. Alamosa River and Terrace Reservoir. . .
With the application of water treatment technology, metals loading is rapidly reduced. Water
treatment will progress towards achieving nmrative and numerically derived remedial action
objectives. After an evaluation of the capacity for contamination reduction to the Alamosa River
and Terrace Reservoir by conditions at the Site, time required for iMplementation, capacity for
response to chanvng conditions, and cost, this remedy is best suited to allow progress towards
achieving interim RAOs. .
1.10.5 Preference for Trea1ri1ent as a Principal Element.
. .
This interim action does employ treatment as a principal element, and is therefore in furtherance
of meeting this statutory requirement. Through a combination of cyanide destruction, treatment
of acidic-metal-laden waters and containment of AMD, the selected remedy addresses the
principal threats posed by contaminated surface waters. Therefore, the statutory preference for
remedies that employ treatment as a principal element is satisfied. .
, . '.'.
+. "~".. '.~. . .
".. . ",'..'
. .
S6
- -
--,
. '. ~ . ,"..,. .
.. . - . .~. ."-'--'..
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".---"""--
"
2.0
RESPONSfVENESSS~Y
" " "
" This Responsiveness Summary was developed in accordance with the EP A guidance document, "Community
RelatioDS in Superfund: A Handbook" (EPAlS40IR.921009). - ,
2.1
Responsiveness Summary Overview
. As part of the public comment period, the U.S. Environmental Protection Agency (EPA) and the
Colorado Department of Public Health and the Environment (CDPHE) identified their preferred
alternative for water treatment at the Summitville Mine Superfund Site (Site) based on
information provided in the Water Treatment Focused Feasibility Study (Water Treatment FFS).
, The preferred alternative addresses the interim remedy for treating acid mine drainage (AMD)
originating from sources altered or disturbed during mining activities at the Site and water
containing cyanide orivnatjng from the Heap Leach Pad (HLP). This alternative is presented in
the Proposed Plan for Water Treatment issued by EP A in conjunction with the Water Treatment
. FFS.
The major components of the preferred alternative include:
. "
Continued treatment of the Cropsy Waste Pile (CWP) drainage and the French
Drain waters in the Cropsy Water Treatment Plant (CWTP).
.
Destruction of cyanide in the water from the HLP in the Cyanide Destruction
Plant (~DP)/Metals Reduction Plant (MRP) until the water quality meets remedial
action objectives. ' "
.
Completion ofHLP remediation, followed by, the conversion of the CDP to treat
AMD.' The MRPwill,becioseclan4 wi.1l~ o~~Site as a contingency facility.
" Containment of AMD during peak surface water flows that exceed the CDP
capacity (500 gallons per minute). The contained water will be treated before
being releaSed into Wightman Fork. "
.
Comments were received during the extended public comment period by interested parties in
Summitville and the surrounding areas. The concerns regarding water treatment at the Site '
include the lack of significant AMD treatment until 1996, a concern that water quality standards
in the Wightman Fork and Alamosa River"may not be met, the nature of the CDP process, the
disposal of the resulting sludge, high operating and maintenance costs, and statutory compliance
with the NCP.
This Responsiveness Summary addresses all o(the verbal comments received during the public
, meetings an4 all of the "written comments submitted during the public comment period.
TranScripts fro~ the public meeting and written comments are available in the Administrative
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"
Record. Documents in the Administrative Record are available at the following locations:
Del Norte Public LibI'afY
.790 Grand Avenue
Del Norte, CO 81132
(719) 657-2633
Hours: Mon-Sat 1 :00-5 :00
Conejos County Agricultural.and
Soil Conservation Service
, Box 255
, 15 Spencer St.
La Jara, CO 81140
(719) 589-6649
Hours: Mon-Fri 8:00-4:30
EP A Superfund ~ecords
, Center
, 999 18th St., Suite 500
Denver, CO 80202-2405
(303) 294-1807
Hours: Mon.-Fri. 8:30-4:30
The comments are grouped according to the topic of concem. Therefore, issues or concerns that,
were duplicated will be addressed only once' under the topic to which it pertains.
2.2
Response to Water Treatment Specific Comments
2.2J.. ,Summaxy and Re~nse to Local and Communi~ Concerns
This section summarizes and responds to the qmjor issues and concerns raised by the local
, community. In this document, "local community" refers to individuals who live in the
immediate vicinity of the Summitville Mine Superfund Site.
2.2.1.1
Water Treatment
Comment 1:' " '
The treatment of AMD, using the preferred alternative, is inadequate. The preferred
alternative can Dot begin significant treatment of acid mine drainage until 1996. ' Also, the
CDP has a tJ:eatment capacity of only, 600 gpm, which makes it inadequate for AMD '
treatment flows generate~ n~rIr $ .,on~.out ~(they'~., It~oul.ct Dotbe p,ossible to 'treat
other Don-point sources until the completion' ofthe'collec:tioDicont:ainmentipumping f~ture
in late 1996. Even then, flows in excess of 1,000 gpm would be discharged ,untreated to the
Wightman Fork. How much water can be treated at one time and how long can it be
treated? ' "
Response:"", " " '
The CDP has an estiml'lted AMD treatment capacity of 500 gpm. The CDP, MRP, and
CWTP combined have a treatment capacity of 1,000 gpm. The:water treatment activities
at the Site are targeted to treat point discharges of AMD flows from the Cropsy Waste
Pile (CWP), Heap Leach Pad (French Drain Sump), Summitville Dam ImpoundJ;nent
(SDI), Beaver Mud Dump (BMD), and the underground workings. After the corrective
action for Chandler adit plug, the Cropsy Phase n removal ofCWP, BMD, and SDI, and
detoxification of the Heap there is expected to be a continual decrease in flows of AMD
and improvement in water quality. " '
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The CDP, which is expected to have an AMD treatment cap~ity" of 500 gpm, has been
selected to treat the A1vID while the MRP will be shut down. This decision is based on
the fact that the MRP only will have an estimated A1vID treatment capacity of 400 gpm
and will require a more costly conversion than the CDP.
" "
According to current coDstruction schedules~ the construction of the collection!
containment/pumping feature could be accomplished in 1995. This would ensure
containment of all A1vID over 500 gpm flows for 1996. . Contained waters will be treated
and discharged during low flow months.
Non-point source discharges, such as the contaminated surface nm-oft: are defined as
contaminated surface flows. "These non-point sources are mitigated through reClamation
activities such as regrading; covering with top-soil, revegetation, and capping. The
preferred alternative addresses these flows for treatment in the short-term through surface
water control measures which direct the surface flows int9 the containment structme.
. "
. '
The treatment capacity of CDP is different for HLP leachate and AMD. The maximum
treatment capacity is deteIri1ined by the hydraulic capacity of treatment vessels and/or the
maximum sludge handling capacity (as determined by sludge dewatering equipment).
The maximum hydraulic capacity of CDP is 800 gpm which applies to leachate treatment
capacity. HLP leachate has (comparatively) low solids content and; therefore, sludge
dewatering is not a problem. "
The treatment capacitY for AMD (very high solids content) is determined by sludge
handling and clarification ability of the plant. This treatment capacity has been estimated
as being 500 gpm based on cmrent data from on-site ~ treatment. "
. ... ~ ,', . .. ,
. ." ," .' .,'." . .
Treatment Capacities of the three treatment plants for HLP leachate and AMD are as
follows: "
HLP Leachate Treatment
" "
CDP and MRP Total:
800 gpm
A1vID Treatment ."
CDP: " 500 gpm
MRP: " 400 gpm
CWTP: " 100 gpm
Total Capacity: 1~000 gpm for AMD treatment
..'
.' .,
Alternative #4 involves A1vID treatment by the CDP and CWTP for a total treatment
" capacity of. 600 gpm. Costs for the CWTP are included as part of the CWP FFS remedial
action. "
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"
" Comment 2:
The FFS did not mention what size plant they would build for Alternative #6 (IROD Alt.
#5). " ""
R~onse: "
The treatment capacity estimated for Alternative #6 was a peak capacity of2,OOO gpm or
2.88 mgd. This plant would be able to treat all flows of AMD (based on historical data)
without the need for surge capacity. " "
~
Comment 3:
A group of commenters submitted a proposed water treatment plant (pWTP) to treat all
acid mine drainage leaving the Site. The suggested method of treatment is time
precipitation. The PWTP would be located above the con.t1uence of Wightman Fork with
Cropsy Creek. The PWTP should 'be located below the SDI, so that it could take
advantage of gravity flow aDd so it could treat all AM» on-site without incurring pumping
costs. Proper placement of the PWTP will alleviate the need'to pump water uphill for"
water treatment which would be necessary under the EP A's preferred alternative. . By
extending the 550 diversion ditch and constructing another ditch on the northeaSt side of
the Site, it woldd be possible to catch all AMD generated on-site. Construction costs for
these ditches are estimated to be $3 to $4 million.
"Re~nse: ." "
" The PWTP is essentially the same as Alternative #6 (IROD Alt. #5) and, therefore, it has
the same limitations as Alternative #6. These limitations include the following:
.
It costs approximately $5.3 million more than the preferred alternative;
It has higher O&M costs because it must operate year round; .
~ ~t9~,n~! ~ve ~~~~sto~c:, capac.ity and, must be designed to treat peak
flow:. ..." . " "
, .
It does not utilize the existing facilities; and" "
It requires the co~tion of a new facility that would be demobilized in
4 years when the Site has been' successfully remediated.
.
.
'. "'~'" '. '. :
.
.
In addition, lime precipitation produces almost double the sludge which is produced using
a hydroxide process. .
Comment 4: "
The SDI will be used for excess storage of runoff in the sprin~. Upon completion of water
treatmen~ the pond can be converted to a constructed wetland. Because of the limited
capacity of the existing treatment plants under the EP A's preferred alternative, the pond
will "not be able "ta hold excess water and will be constantly .disturbed. The PWTP allows a
60
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stable water body in which development of the constnlcted wetland will be accelerated.
ReS1)onse: ..
. The comment indicates tbatat least one party .may be confused about the need for
constrUcting the containment structure. The structure will be built specifically to hold the
excess AMD when the plant is in operation and to hold the contaminant flows that occur
during the late fall, winter, and early spring months when the treatment plant is shut .
down. The containment structure will have a 100 million gallon storage capacity. This
will enable the plant to operate at full capacity during the late spring, summer,. and early
fall to process the water which has collected in the structure during the winter months .
when the plant is not operating. The use of the structure for containment and a wetland
are mutually exclusive. The wetland will be evaluated in the sitewide FS.
Comment S: . . .
The assumption of needing the CDP for further cyanide destruction is in conflict with the
. preferred alternative' for the Heap Leach Pad, which proposes using bacteria for cyanide
destnlction.
Res;ponse: .
No conflict exists. The CDP will be required for cyanide destniCtion treatment of the
HLP leachate until the plans for biodetoxification of the Heap are complete and the Heap
is dewatered. The Heap Leach Pad FFS proposes the detoxification of the ore using
cyanide destroying bacteria; it does not propose treatment of leachate Using bacteria. .
. Comment 6: ,,'.' .. '-. ';~: .. .. ~.'''..~...'--:'.... . ~..... ...:... , -..' .. - ,. - '" . .. .." .
Is the hydrogen ion included in the list of metalremova1? You are not going to treat for
that?
ReS1)0nse:
No. Treatment parameter$ are not designed. to reduce the hydrogen ion concentration in
the effluent. . . . .. . . .
- "'..' ..
Comment 7:
The PWTP takes advantage of other remediation phases and uses site advantages
efficiently. AMD treatment can be done while other remediation actions are in progress
aDd other treatment plants can be salvaged and sold as soon as HLP bio-remediation is .
started.
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"
Re~onse: . .. .
The Proposed Water Treatment Plant (pWTP) does not utilize the existing facilities '
throughout the remediation process. As a result, the. construction of a completely new
facility is required which ultimately will incur greater capital and O&M costs than the
preferred alternative. Considering the extreme weather conditions at the Site and its
remote location, it would be necessary to buiid a new plant with some degree of structural
integrity if it has to serve as the only operating facility at the Site; i.e. support facilities
like office space, showers, lunch areas, maintenance areas, heavy equipment maintenance
. areas, etc. These structures would have to be located near the plant or in the same facility.
Only a facility with these Capabilities would allow the salvage of all other plants at the
Site. It would not be possible to construct all of these facilities in a modular fashion to,
. . facilitate their movement from site to site. . .
..
The preferred alternative will convert the CDP to treat AMD in 1995 and the MRP will
be shut down and held in reserve. When Site remediation is completed, the treatment
facilities will be available for sale or salvage depending on their value and condition.
Comment 8:
Several concerns were raised regarding the hydroxide sludges produced at the Site. It was
pointed out that they tend to be unstable and are subject to the release of metals over a
wide pH range. It also was noted that no study has been included in this FFS describing
how different sludges react with AMD and precipitation. This is a concern because Site
disposal of the sludge is contemplated.
The PWTP is suggested to be configUred for sulfide precipitation. Because metal
hydroxides can be easily leached from the sludge, ~posal methods are ~o~ complicated
and 'expensive than those for sUlfide sludges. A process that produces more stable sulfide
. slucJges, like theslQdge.produced at the~'Would,a'Void..the.-Deed.to.andertake future '
. . . ~',".......
remedial actioDS caused due to inadequate interim action. Using the MRP, instead of the.
CDP~ would b.e an obvious solution and the MRP would not need extensive retrofitting to
treat AMD. However, using the MRP was not one of the 'alternatives that was offered. .
R~onse: ' , '. . .
The hydroXide precipitation technology for AMI) treatm~t is a conventional, industry
accepted technology. The sludge generated by the water treatment processes are buffered .
alkaline, metal hydroxide sludges which will be disposed off-site as a resource recovery
or placed in the South Pit. The South Pit is intended to be lined and capped to isolate the
sludges and other contamin~ted wastes (such as tailings) from contact with acidic waters
or incident precipitation. The stability of the sludges on-site will be studied fmther ,
. during final design.
The hydroxide sludge is buffered with alkali hydroxides ~ch will prevent its
62
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'.,' ~....... '. _. . . .
.. .
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~
dissolution when in contact with low pH waters such as precipitation. The solution to
. avoid remobilizing metals from the sludges is to prevent or reduce contact with AMD.
This is done by enclosing the sludges with a cap having a very low permeability.
The essential difference between the hydroxide and sulfide treatment processes is that the
sulfide precipitation process is a polishing step, and would be extremely expensive
(reagent and sludge handling costs) ifused as the primary metals removal process.
Conventional industry design and operation of stilfide precipitation processes 'entail the
initial removal of metals through hydroxide precipitation prior to sulfide precipitation.
Even' if AMD is treated thr~ugh the MRP, the sulfide precipitation process would not be
used. Based on existing data, the hydroxide precipitation process is Sufficient to meet the
water quality standards stated in this FFS for all streams except the streams containing'
the cyanide-copper complexes.
Hydroxide sludge also haS the advantage of potential recycling opportunities.
Comment 9: .
The current water treatment process is a closed loop. The only positive effect of on-going
water ~eatment is the destruction 'of cyanide.
ReSi'0nse:
The cmrent water treatment processes at the Site include treatment ofHLP leachate in the
CDP and MRP prior to discharge. Some of the treated leachate is recirculated to the HLP
to rinse the ore because there is not a source of fresh water on-site to use for this purpose.
. The rinSing program is effective and has achieved a 90% reduction in both cyanide and
copper concentrations in the leachate.:. The_water .treatm.ent actiVities also .involve.~ ., " '.
treatment of French Drain waters and Cropsy Waste Pile waters in the CWTP.
Comment 10: .. .'
How well will the proposed impellers and bowls on the pumps hold up to acidic water?
Response: . .
Acid proof pumps such stainless steel or rubber lined pumps are commercially available.
and have considerable resistance to COI1'Osion.
.
Comment 11:
The new proposed alternative can be actively treating an point and non-point sources of
. acid.mine drainage a year earlier than the EP A's preferred alternative. Construction can
be done and the plant can be operational nearly a y~ prior to the estimat~ for
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"
Alternative #5 (IROD AJt #4).
. .
. Re~onse:. .
It is doubtful that a new treatment facility could be constructed and on line by the spring .
of 1995 one year ahead of the preferred alternative. In fact, the containment structure,
identified in the preferred alternative, is anticipated to be in place by the end of 1995.
This will enable AMD to be collected through the winter of 1995-1996 and treated in the
spring of 1996.
Non-point source discharges, such as contamin~ted surface nm-o£t are defined as
contaminated surface flows. These non-point sources are mitigated through reclamation
activities such as regrading, covering with top-soil, revegetation, and capping. Short-
term effectiveness will be mitigated by collection of selected surface water flow into the
containment structure.
Comment 12: .
The duration of water treatment by the PWTP is flexible and more effective in comparison
to that of Alternative #5 (IROD AJt#4), given the assumptions of that alternative.
- Re~onse:
Alternative'#5 compensates for fluctuations in flow and water quality using a
-. containment pond. Specifically, the concentration of the contaminants in water that will
be he~d in the containment structure will be roughly an average of the high and low
concentrations that enter the structure. Since cont~minant levels in the containment
structure will not fluctuate to a great degree, it will be easier to treat AMD using the
. prefeIred alternative. In addition, the treatment plant will be in operation only part of the
year which will result in lower O&M costs for the preferred alternative. Therefore,
Alternative #5 does offer. flexibility .and effecti.yeness.-.. -- ... .-'. .
Comment 13: . .
. If the PWTP is implemented, a .water treatment plant will be place in ~e event of failure of
any remedy. Failures could occur in capping, adit plugs, stabilization of Cropsy Waste Pile
. footprint, and unforeseen circumstances.
R~onse: .
During emergency response conditions associated with a failure, a single facility utili7-ing
one treatment process may not be abie to treat varying sources of contamin~tion without
extensive and time consuming modifications. However, the preferred alternative offers a
benefit that is not realized with one treatment plant. The preferred alternative can store
excess water for ~atment and divert it to the necessary treatment plant. ..
64
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. . .
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, '
, '
- -.--.. .~,;- - ~ . ...~~....:-
"
. ':::'--...1. .~._-- .:....o.---:'_.'-~ ...
Comment 14:
The water treatment plant should be the hub for integrating the four focused feasibility .
studies and for all remedial actions to meet the EPA's stated objectives. .
. .' . . .
Res.ponse: .
All four activities must achieve common objectives set out in the FFSs. However, the
water treatment plant is the focus of water treatment activities. Other remedial actions
should be investigated, planned, designed, and implemented on their own merits. For
example, operating the reclamation project through the water treatment plant would be
inefficient and at best would add a layer of D"IRnafement that would increase costs and
delay decision ma1dng. . .
Comment 15: .
, The preferred alternative (Alternative #5)(IROD Alt. #4) does not accomplish any of the
specific RAOs described at the beg;nning of ~ document. In contrast, the new PWTP
will meet or exc~ aU the RAOs established for the site by the EP A.
. Res.ponse: .
EP A has identified a preferred alternative which will meet the RAOs and interim
remedial action goals. Specifically, the preferred alternative accomplishes the RAOs set
for the Site by:
.
'.
.
.
Reducing the total contaminRnt load entering Wightman Fork - .
specifically, by treating the AMD from the CWP, HLP, French Drain, the
SDI, the BMD;
Treating AMD from the point sources listed above begjnning in 1995,
'after the' HLPis dewatered;~: '. " .~. .'.. . " .
Reducing and ulti.n1ately e1iminat1nf human health and adverse
environmental effects downstream of the Site; .
. Reducing the need for continued expenditmes for water 1reatment at the
Site by remediat1nf sources such as the HLP; and
. Encouraging early action and acceleration of the Superfund process .
through the Emergency Response Removal Actions (ERRA) and
Remedial InvestigationIFeasibilitY Studies (RI/FS) activities'which have
taken place or are on-going. '. - .
.
.
..
Comment 16:
Is there any way to set up a treatment plant at the reservoir - before it flows down river
any further? It would make sense to locate your water treatment unit(s) as far.
downgradient as possible, even if entails relocation of the eXisting fac:ilities. .
65
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Re5i'onse:
In order to minimi7e the harmful surface water effects of the Summitville Site, it is
. prodent to locate the treatment facilities as close to the sources of contamin~tion as
possiple. The preferred alternative does this efficiently for the least cost by utiH7ing the .
existing treatment facilities. .
.
Comment 17: .
Is it possible to treat all the contamin~ted water at the Site while other areas of the Site are
being remediated? With this solution, the people who.live in the area and the people who
have cattle and farmland in the area donot.receive more CODtamin~tion.
Response:
The EP A is presently treating AMD at the CWTP and cyanide and metals at the CDP and
MRP under the ERRA. The preferred alternative will treat AMD ftom the CWP, HLP .
(French Drain Sump), SDI, BMD, and the underground workings before the 1995 spring
nm-off period and it will have a new containment structure in place prior to the 1996
spring nm-offperiod. The cost of the preferred alternative is estimated to be $26.8
million, the lowest cost of the comprehensive Alternatives #4-#6 (IROD Alts.. #3-#5).
This treatment, in conjunction with the stated remedial activities is expected to improve
Water quality in Wieh1Ttl~n Fork and will meet the existing water quality standards for
Segment 3b of the Alamosa River.. .
Comment. IS:
An evaluation of the 1993, Ecology and Environment (E&E) report on point and non-point
sources of AMD reveals that a total of 1.6 million gJJd of AMD flow occun at Summitville .
during the spring runoff: Of which, 1.2 mgd is being discharged directly into Wightman .
Forkwithout~tment., '.-'..,. .,..",".,.,.... .:.,".J.....-..."'" ."... ".
. ..' ." "'.,. ..'
Response: .
The evaluation performed by E&E was pre1imin~ry based on SCMCrs operational data.
E&:E's estimate of spring flows.was actually less than 50% of the 1993 spring AMD
flows (Table 3, FFS). However, since the report was issued, the EP A'has made
significant advances towards the mitigation of the point sources of AMD thereby
reducing the amount of AMD which is generated at the Site. Some of the actions taken
by the EP A are:
1.
Plugging ~f the Reynolds and Chandler adits:
.
- .
The plugging of the adits is expected to not only have the immediate effect of
reducing the flows ftom the adits, but also a long term reduction of gene~on of .
acidic water underground by floodIng the underground workings and reducing the .
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available oxygen for the acid generation reaction.
2.
Removal of the Cropsy Waste Pile for placement in the mi:i1e pits:
.., '-. '.". .,.,' .
The Cropsy Waste Pile impounds surface waters behind the Heap and causes
AMD to overflow the dike each Spring. The AMD impounded at the CWP also
cont::rm;n::rteS the ground water underneath the Heap .and; therefore, the waters in
the French Drain Sump. More than three million yards have been removed from
the CWP and placed in the mine pits. In the process, many of the seeps, which
were cont~m;nated by the sulfidic rock in the CWP, have been uncovered. These
seeps will be isolated and monitored. It is anticipated that they will eventually (if
not immediately) reach acceptable water quality' and will not ~quire any active
treatment.' '
3.
Removal of the BMD and the SDI is ongoing:
The BMD and the SDI have been documented as significant contributors of AMD
'to Wigh~ Fork (EElCA, E& E, 1993). The Cropsy Phase n project has
targeted the complete removal of the AMD generating waste rock and tailings
from these two locations for placement in the mine pits. Therefore, these two
somces of AMD are expected to be eHmin::rted helping the Site to achieve the
~()s. '
4.
Filling up of the mine pits to reduce infiltration of precipitation into the ground
water and contact of precipitation with high sulfide rock in the underground
workings. This ~ also expected to reduce the gen,eration of the AMD that has
historically drained frOm the Reynolds adit. "
".j-" .".'., ,
" " r. .
2.2.1.2
Cost
Comment 19:
This FFS is poorly researched in almost all areas and capital costs as well as O&M costs
are substantially inaccurate. O&M costs of this alternative are very high 8J!Id require an
unnecessarily large amount of personnel to construct and operate. Year round Site access
and maintenance will be required for several years under this alternative and these costs
are not included in the estimates for this alternative. ' .
Specifically, the computation of capital costs and O&M costs for Alternatives 5 & 6 (IROD
Alt. #4) are inaccurate in several ways: 1) they do not take into account retrofitting of
the CDP nor,the containment required for the hydroxide sludges; 2) the O&M of"
Alternative 5 and their associated costs are questionable; 3) AIternativ~ 6 requires' a plant
at the .bottom of the site, is superior to Alternative 5, and' achieves the water quality set by
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the RAOs. The capital costs for alternative 6 have been .grossly oventated. Outsid~
industry sources indicate that $1 to $1.50 per gallon treated should be used to calculate the
costs for new, salvageable, plants. This would result in costs of$7.5 million for.a treatment.
plant which is capable of treating 5 million gallons per day(gpd) (3,472 gpm). Even adding
in S2.5 million for building it at Summitville, would still result in capital cost that are $5
million less than the costs listed for Alternative 6 in the FFS. Table 7 presents the current
-cost ofHLP leachate at $9.70/1000 gallons. However, Tables 11-14 use 532.18/1000
gallons for HLP leachate treatment. Table 7 also presents the current cost of AMD
treatment (no cyanide) at $9.30/1000 gallons. However, Tables 12 and 13 use 521.54/1000
gallons for AMD treatment (calculated based on the line item labeled "CDP Treatment
Costs per week" and '~CDP operation at 500 GPM"). These numben are inconsistent. ..
Re$,pOnse:
The true cost of a new plant was established at between $4.5 and $S million.. O&M costs
are higher than those estimated by the commenter because the actual O&M costs include
Site maintenance, drainage control, and security/access costs.
The capital costs and the O&M.costs of each alternative have been extensively
researched. The cost for Alternative #6 was based on a 2,000 gpm plant (approximately 3
mgd) that would effectively treat all the water at the Site that did not comply with the
:acceptable discharge requirementS. The plant was scaled to treat the peak spring flow
based on current and past site c~terization. data. In addition, the cost estimate
assumes a reduction in treatment volume as reflected by. a reduction in treatment costs for
years 3,4, and S. Because there is no surge capacity factored into this option, the plant
has to operate all year round to comply with remedial action goals for wa~ quality in the
Wightman Fork .and AIamosa River. .
Alternative #S factors m a surge capacity of 100 million gallons whi~h would be .
. sUfficient.tohold.all AMD..flows.tbrough th~1ate faii~.w1mer and. early:.~. It is
therefore assumed that the plant will only operate in spring and summer to treat and
discharge all contained waters.
O&M Costs:
The cost of treating A1vID through the CDp.is based on historical cost data at the Site.
The bare costs of treating AMD are tabulated in.Table 7 (FFS).~..These costs were . , .
demonstrated to be competitive with plant O&M costs during evaluation of the various
technologies submitted by 23 companies in.response to the 120 request for proposals
(RFP) sent out by the EP A. The treatment costs also included site maintenance costs, site
drainage control costs, and security/site access costs.
The rationale for including these costs with Site maintenance is that when there is no
water .treatment activity at the Site, there is no reason to maintain Site access. Therefore,
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Site maintenance costs have not been factored into the other three FFSs. The Site
, maintenance costs are based on historical costs ofEP A's operation on-site.
Alternative #5 VS. Alternative #6:
Alternative #5 and Altei-na.tive #6 are equally effective in meeting the water quality goals
for the Site. IIi addition, Alternative #5, with its storage containment feature, provides a
flexibility for design of other remedial activities a the Site in terms of maximum
treatment capacities, variabilities in flows, ability to shut down in the winter months, etc.
These options are not possible using Alternative #6. '
Capital Cost:
The cost estimates for Altemative#6 in the Water Treatment FFS were calculated using
conventional esrim~ting techniques. The estimates were then cross referenced' with the
cost proposals submitted during the RFP process. The plant is sized to treat 2,000 gpm
(approximately 3 mgd) during peak flows. Using the numbers provided in the comment
above ($1~50/gpd), the cost for a new treatment plant would be $4.5 million. The Water
Treatment FFS assumes a cost of$5.0 million.
One commenter has estimated that it will cost $10 million for the construction of the new
facility. This estimate is very high in comparison to the EP A's preferred alternative cost
of $5 million (Table 14, FFS) because the commenter estimated the flow rate at 5 mgd. If'
the commenter had used 3 mgd, the commenter would have arrived at $4.5 million,
roughly the same figure as the EP A ($5 million). The EP A does not believe that a $2.5
, million fudge factor needs to be included for construction at the Summitville location.
Therefore, the commenter's and the EP A's cost estimates to construct a new plant per
Alternative #6, are essentially identical;- '~ '!:",'," ", ,: ',: ::. , " , ,".' , .' '
Treatment Costs: . ,
The $9.70/1,000 gallons cost shown in Table 7 is for labor, utilities, and reagents only.
The $32.18/1,000 gallons cost for ffi.P Leachate Treatment shown,in Tables 11 - 14
, includes the items above as well as the operation of the HLP, CDP, MRP,- CWTP, the
laboratory, the maintenance of these facilities, the handling of all sludge, and site support
ofMorrison-Knudsen's drilling and bio-remediation operations.' " , '
The cost of$21.54/1,000 gallons that the commenter calculated using the information in
Tables 12 and 13 was calculated using assumptions that lack detail. No coStS were
presented to treat units of 1,000 gallons because the flow rates are variable and not all
treatment facilities will ~e in operation during the,entire year~ "It~ likely that the flow
rate wQ1 range from 500. gpm to as low as 200 gpm, while it is expected that the MRP
will be in operation only during the months from May to July."
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. Comment 20:
To what degree of accuracy are the costs estimated?
ReS1')Onse: .
The FFS is based on all currently existing site characterization data, operations data, and
historical costs data. Capital costs and O&:M (:Osts in this FFS are in line with industry
accepted estimates. According to OSWER Directive 9355.3-01 costs estimates must
have a desired accuracy of +50 percent to -30 percent..
Comment 21:
Costs to retrofit the CDP to address the additional flow are not adequately computed in the
Water Treatment FFS. .
.. R~onSe: . .
The following have been taken into consideration for converting the CDP to treat AMD:
.
the cost of rerouting the efiluent line to Wightman Fork; and
the cost of installing a new pumping system from the storage pond
to the CDP - tbis is factored into the cost of building the storage
pond containment structure.
.
Comment 22: .
. Many established alternatives for water treatment were not given any consideration as
alternatives: More efficient/cost effective possibilities were not given consideration as
. alternatives. .
. '. I ~ ',-
. .'" . -" .' " . 'J ~ ".' ~ .... .. .;.. '." 'I ...., ---:-..... ,",' . ::. ~.
R~nse: .' .
A comprehensive discussion of treatment alternatives is presented in Section 3.5 of the
Water Treatment FFS. The EP A sent out a Request for Proposal (RFP) to all vendors for
potential water treatment technologies. All responses to the RFP have been considered
by the EP A for applicability at the site. All of these technologies were considered in
~~~the~~~~mthe~=~~m~~~~~OO~
#S), the new treatment plant. . Capital and O&M costs in the cost estim~tes for ~temative
~ are comparable to those obtained in response to the RFP from the industry.
Comment 23:
Is there a possibility that if your interim action does not work, you're not only going to
spend the 528 million on Alternative #S (IROD Alt. #4), but you may.find out you have to
spend 530 million on Altemat,ive #6 (IROD Alt. #5), any way? .
70
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ReSJ'ODse:
Given EPA's present understanding of the Site, the preferred alternative addresses the
RAas better than any other alternative. If conditions at the' Site radically change, it may
be necessary to implement additional remedies which will increase tI;1e cost to remediate .
the Site. . "
. Construction of a new treatment plant in not consistent with the Sitewide Remedial
Action Objective "to' reduce or eliminate the need for continued expenditures for water
treatment at the Site." The preferred alternative, if successful, will meet this RAO by its
progression from the etimination of water treatment during low ~ow periods to passive
water treatment. .
,/
Comment 24:
There were several coniments regarding the cost estimates for Alternative #5 (IROD Alt.
, #4) and Alternative #6 (IROD Alt. #5). The specific questions addressed the following
issues:
a.'
b.
The capital cost for the construction of a new plant in Alternative ~.
The 0 & M costs for both Alternative #5 and Alternative #6'-
One comment specific:ally included two cost proposals for the cOlIlStruction of a
water treatment plant and its operation. "
Co
Res;ponse: ,. .
The cost estimate for Alternative #6 was based on the concept of single water treatment
plant that would be located at the lowest possible point at the Site where all contamin~ted
flows would be channeled by gravity flow.' This plant was sized for peak flows during
spring nm'offwhich can'beu'high"2,000"gpm.:".])aring1lIe.winter'months.this plant,will..,., ...
be treating continuous lower flows. which could be as'low as a 100 gpm.
The technology to be Used at the plant was not fin~ti7.edsince this would be a decision for
final design. However, all vendor technologies proposed in response to the RFP were
considered for the purposes of conceptual design. Approximately 120 RFPs were sent
out by EP A and 23 responses were received. Other industry accepted technologies were
also considered and are discussed in Chapter 3 of the FFS. '. - ':. ...
The capital estimate for Altemative #6 (Table 14, FFS) was based on the following
assumptions:
1.
The leachate in the HLP will be treated until August 1995 when the Heap will be
completely dewatered according the design of the bio-detoxification of the Heap.
The cost of treating the leachate is included in the immediate capital costs for this
alternative. '
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2.
The new plant will be coi1Structed at'the Site, between June, and September of 1995
and will be ready for start up in late fall.
, , All other plants at the Site will be shut down and moth-balled at this time for
" future use or salvage. , , '
, The treatment plant will operate continuously, as a round-the-clock operation to
prevent the discharge of any and all contamin~tP.Ci waters in order to ensure the
water quality goals oftbiS remedial action. This treatment flow rate will be low in
the winter and maximum in the spring. ,
The rest of the site will be shut down When there is no other construction
,operation. ' , "
3.
4.
5.
The cost estimate for the actual construction of the new plant was as follows:
Cost of constructing new plant:
$ 3.5 - 3.85 Million dollars (assumes that some equipment
from the Site will be reused such as filter presses,
laboratory equipment etc.) , ,
Cost of rerouting pipelines and
Utilities:
Reconfiguring drainage and
collection sump:
Contingencies (10%):
$ 350,000
$ 300,000
$ 500,000
Total Estimated Cost of facility:
$ 5.000.000
, ,
, One set of-comments included two cost proposals for construction and operation of a water
, treatment plant at the site.
The first proposal bad been submitted to EPA,during the RFP process. The proposa11isted the
capital costs for construction ofa.l,OOO.~p1ant aiS2.44-million.''iThe'proposer.~CQ~
and provided a ball park revised estimate of $3.8 - 4.0 million'for a 2,000 gpm plant. The plant
was not portable or modular. The pro,cess being used was a variation of hydroxide precipitation
using lime and soda ash. During the RFP review process, several of the reviewers felt that this
process would increase the sludge volume generated by the treatment process.
, '
The other proposal was also for the construction of a ~ mgd plant for $3.125 million. The
proposer said that increasing the plant capacity to 3.0 mgd would raise the cost to approximately
$ 4.0 million. This is in the same range as the EP A's estimate.
Neither of these proposals bad support work like pipeliIies on-site, utility re-routes, or drainage
reroutes costed. '
72
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O&M Costs:
,The O&M costs for both Alternative #5 and Alternative #6 were based on cost propoSals
received trom the industry as well as historical costs associated with treatment and site'
maintenance. The treatment basis for the costs is the following:
"
Peak flows: 2,000 gpm
Low flows: 100 gpm
Total Volume Treated in 1995-96: 265 million gallons
Total Metals (COC) Concentration in water: 2000 mgIL
, Total Sludge produced in 95-96: "24 tons/day
The treated volume is assumed to reduce by 25 - 30 % each year for the four years of treatment.
The treatment costs contain all Site maintenance costs, Site security access maintenance costs
etc. These treatment costs have been found to be historically accmate and take into account all
the contingencies that could occUr at a remote location such as Summitville, with extreme winter
conditions. '
The two proposals have very marginal discussion of O&M costs for water treatment. One
, proposal contains a cost of $ l.40/pound of metals removed. This would translate to a cost of
$6.2 million for the first year which is unreasonable. '
, The second proposal has been,submitted by a company that has never visited the Site. The
proposal1ists the annual cost of operating the plant as $ 1.0 million. The proposed annual ,
O&M costs of $ 1.0 million would not even account for the delivered cost of reagents for treating
this volume ,of water. Based on the eva1uationcriteria used for screening technologies this
proposal would have to'be"considered-asllon~reSponsive:~.':"'.':',' ". -",' . " ' > ' "', ' "
Comment 25: ' ,
What is the cost difference to build the storage capacity in comparison with bUilding a new
treatment plant? '
Res.ponse: '
The storage facility at the SDI is estimated to cost approximately $1.6 'million. Whereas
a new plant will cost between $4.5 and $5 million.' ,
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2.2.1.3
Water Qualil)l
Comment 26: .
.. The preferred alternative wiIl.not meet water quality criteria established by the State and ,
Will require official degradation of estab~hed stream standards. .
Re$1)onse:
Interim action levels for discharges from the water treatment plant are given on page 23
of the Water Treatment FFS. The IALs will be finali7,ed upon EPA and State.approval.of
the IROD. Water that is not treated under the prefen'ed alternative prior to 1996 mayor
may not meet IALs. After 1996, the AMD coming from the point sources liSted in the
Water Treatment FFS will be collected and treatedto meet the Site discharge '.
requirements. . . '.
The existing water treatment plants at the Site are expected to meet the water quality
standards as specified i1i the IALs in Section 1.4.1.5.4 of the FFS for all treated waters.
Minor plant modifications may be necessary to accommodate changjng Site conditions
which result from other source containment actions (i.e., HLP, CWP, and ReClamation).
EP A believes that this fact increases the short-term effectiveness of thiS alternative.
Comment 27:. . . .
The PWTP would meet or exceed water quality criteria established by the State without
having to degrade the Stream Standards. .
R~onse:
The preferred alternative will meet or exceed water quality standards. lALs for
discharges from the water treatment plant are given on page 23 of the Water Treatment
FFS.These interim.actioD levels will.be finali'7-ed.upon EPAandCDPHE,approvalof the
IROD. The discharges are expected to meet existing standai-ds. Water that is not treated
under the preferred alternative prior to 1996 mayor may not meet'the lALs. After'1996,
the AMD from the CDP, HLP and French Drain Sump, SDI, BMD, and the underground
workings pomt sources will be c9llected and treated to meet the Site discharge
requirements.
..
- .
Comment 28:
The Water Tr~tment FFS does not clearly identitY the numerical standards by which
discharges from the water treatment systems at the Site are being managed. These
numerical standards should be defined and consistently used when ev~uating and selecting
any remedial action.
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Re~onse:
A discussion ofpo~ntial interim action levels can be found in Section 1.4.1.S.4
, ,Calculated Interim Action Levels on pages 22 and 23 of the FFS. Once the'IROD is ','
, signed by EP A and CDPHE, these values will be the surface water standards for the Site'
at monitoring point WF-S.S, located at the confluence ofCropsy Creek and Wightman
Fork. By achieving these discharge standards, the Site will be meet the ARARs
discussed in Appendix C of the FFS and Section 2.8.2 of this document.
, -,
Comment 29: ' , '
The selection of a' monitoring point for site discharges at mile 45.4 on the Alamosa River,
rather than on the Wightman Fork at mile 5.5 fails to take into consideranon the negative,
impact on water quality from non-site related sources~
R~onse:
The model, used to calculate the Potential Interim Remedial Action Levels listed in
Section 1.4.1.S.4 (pages 22 and 23) of the Water Treatment FFS, incorporated a dilution
factor in the formula that accounted for additional surface water flows between
monitoring points WF-S.S and AR-4S.4. Any chaIige in cont~m;nRnt concentrations
between the two monitoring points can be attributed to COIJ1'Rm;nRnt loading downstream
ofWF-S.s and above 45.4.'
"
Comment 30: ,
, When did tJ,te State of Colorado classify the stream segments? Was if before the Galactic
phase of Summitville or after?" ,
R~nse:~"" , '" ',. ,', , "..," .. .,'.. " . "',' " " '. '.. ..',
, The streams were classified in 1985. Galactic applied forits permit in 1984.'
Comment 31:
What environment are we protecting - that which existed before man ,set foot in the canyon
or an environment that exists only in the p1annen' minds of a pristine mountain stream
filled with trout and rocks unstained by mineraI deposits? ," , ,'::,~
Re51'onse:
The emergency response removal action was performed in order to stabilize the aftermath
of the most recent mining actions at the Site and ,as the initial step to protect human health
and the environment as defined by the RAOs set for the Site~,- In order to achieve the
, RAOs, the Site will und~o remediation to mitigate the effects of the most recent mining
activities. Remediation will affect some of the historic activities as well. - . ,.,
7S
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Comment 32: .
Is the agricultural quality water that we. strive for, water that meets standards set forth in
some.EP A manual or is it th~ acidic water that has been used for nearly a century to make. .
. the agricuitu~ region more productive and to help neutralize the a.lkaline, salt laden
ground water which eventually gets to the Rio Grande?
R~onse:
It is neither. The surface water quality standards set by the State Water Quality .
Commi~on for this segment of the Alamosa River are the standards EP A is trying to
meet. The water that is discharged ftom the Site is expected to meet the IALs contained :
in the FFS and are expected to meet the existing down stream surface Water quality .
standards at monitoring points WF-5.5 and AR 45A located at the confluence ofCropsy
'. Creek and Wightman Fork and Wightman Fork and the Alamosa River, respectively.
Studies are underway to assure that the stream standards are classified appropriately. If
these studies indicate that the stream classifications are not set properly, the State WQCC
may reclassify them according to established procedures.
. Comment 33:
Hthe absorptive capacity of the Terrace has been filled up, basically, by contamina.uts
coming. off SummitviUe, will you be looking at that, and will you be considering action to
cleaning that particular problem up, if it exists?
R~onse: . .
J:he U.S. Geological Survey, EPA, and Morrison Knudsen Engineers are conducting
studies to characterize Terrace Reservoir. No further actions are planned at this time.
.0', ...
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2.2.1.4
Other Issues
Comment 3Ji.. . .
The Water Treatment FFS should discuss how Stream C flows are addressed by the . .
interim remedial actions. and desciibe in detail.the planned '.'corrective measures!' .lor. the
Chandler Adit.
Re$pOnse:
Section 1.4.1.3, DescrilJtion Q.flmlJacted ~ (pages 14 and 15) presents a detailed
description of Stream C and the drainage ftom the underground workings via the
Reynolds and Chandler adits. As stated in Section 2.2, Adit PluUi.ng, the discharge ftom
the Reynolds Adit declin~d to less than 10 gpm after the adit was plugged. The water
76
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quality of Stream C did improve for a period of time. However, plugging the Reynolds
Adit resulted in an elevated water table which caused the Chandler Adit plug to fail. As a
result, it will not be possible to achieve the Segment 3b water quality standards until the
Chandler Adit is plugged. According to the Action Memo, the corrective measures '
planned are considered part of the Emergency Removal Response Action (ERRA) and are
beyond the scope of this document. However, a work plan is c~tly underway and will
be available to the public in the future. For more information regarding the Reynolds and
Chandler adits, refer to the Reynolds Adit Control Program prepared by Environmental
Chemical Corporation (ECC) in October 1994.
Comment 35: . "
No on-site contractor will be needed to oversee the PWTP since operators can' be hired by
the State or by the construction company.
Re$pOnse:
EP A does not support this position. Due to the remote location Qf the Site, an on-site
operator is required. It would take too long for off-site personnel to respond to spills,
equipment malfunctions, and natmal events such as snow storms. During the hours or
days it would take for off-site personnel to reach the Site, enormous environmental
damaee couid occur.
An on-site contractor would also be required to provide Site support services such as
security, road maintenance, Site maintenance, Site drainage control, Site monitoring, etc.,
even with the construCtion of the PWTP. '
Alternative #5,(IROD Alt. #4) visualizes a complete shut down of the Site through the
winter which would,. in -reality,' eliminate'alloontractolS>from-the,Site Jor a significant
part of the year. The Site wouid' only're.opendunng' coDsiIuCtion season'or in' early,' ,
spnng..
Comment 36:, ' '
The company that authored this FFS has no experience in the areas of water treatment
plant design and construction. ',' '
'Re$;ponse: , '
Envjronmental Chemical Corporation (ECC) is one of several nationally recognized
companies that has completed or currently is completing work at the Site. All of these
companies have submitted statements of their' qualifications to the federal government.
All companies that prepare feasibility studies are required to follow OSWER Directive
9355.3-01, Guidance for Conductini Remedial Investiiations and Feasibili~ Studies
Under CERCLA (Interim Final, O~tober 1988). The cost estimates used to prepare each
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alternative contained in this FFS were based on proposals submitted by 23 companies In
response to 120 requests for proposal sent out by the EPA.
Comment 37:
Can you clarify what ECC did and didn't prepare? Was it ECC that recommended a
preferred alternative?
R~onse: ,
ECC prepared the Draft Water Treatment Focused Feasibility Study. Identification of the
preferred alternative was detennined by the Summitville Technical Team (ST!). The
SIT is comprised of experts in the field including personnel from the EP A, the United '
States Bureau ofReclamanon (USBR), CDPHE, Morrison Knudsen Engineers, as well as
other organ;7~tions. '
Comment 38: '
EP A has spent over 540,000,000 on Summitville to date and will spend an additional
S98,000,000. What are we going to get in return for our SI40,OOO,OOO? Who is going to
benefit and in what way? Has there been a cost-benefit analysis done, and if so, how many
dollan of benefit are we going to get for each dollar expended?
Re~nse: , "
EP A attempts to recover money from the potentially responsible parties (pRP).
However, when this is not possible, the Superfund pays for the clean-up. EP A does not,
do a cost - benefit analysis to determine whether it is appropriate to clean up a site. EP A
is required by Congress to clean up sites where hazardous substances present a risk to
' human health and the'environment. EP A is fnlfi1Iing this requirement at the Summitville
Site.' """...,..,....,..~..~-".; ."'C"'., ....'., .", ,', ",,,', '
. . _..... '.., .,." 'I::, "''':'.'....' .i' ,."..1- I
Comment 39:
How long is ','l()ng-term "?
R~onse:
This is a teim which generally refers to the duration of a remediation process or the life
of the remediation project. The Water Treatment FFS defines long-term as over five,
y~. '
Comment 40: , . ,
What is the danger to human health from Summitville? I am concerned about what the
continued use of this contaminated water will eventually do, not only to the land, drinking
water from wells, but also to the livestock and products which are ultimately consumed by
the general public:.
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Res;ponse:
The ERRA conducted at the Site was implemented in order to protect human health and
the environment by reducing the risk of a catastrophic release of cyanide and metals as
well as the release of AMD to the Site. EP A's prompt action and its continued operation'
of the Site facilities has ,enabled the EP A to initiate a remedial action program that will
help attain the RAOs for the Site. . A Risk Assessment (RA) is being conducted by
Morrison Knudsen Engineers as part of this process. Studies such as this RA will enable
the EP A to determine the impact on human health and the environment since the
implementation of emergency response actions at the Site. '
. ..' ... .
2.2.3 .. Comprehensive Response to Specific Legal and Technical Questions .
, '.
'. . "
Comment 41:
When discussing the stream sections where ARARs applied, why do YOUl only look
upstream from Terrace? Is downstream from the Terrace considered?
Re~nse: .... ' .
Water quality standards that are considered applicable or relevant and appropriate
reqWrements for a site are ARARs. . However, not all water quality standards for
segments of the Alamosa River and its tributaries are' ARARs for the Summitville Site.
Identifying ARARs for the Site is not so much a process of looking upstream from '
Terrace Reservoir, but the process ofidentifying water quality standards downstream of
the Site that represent the minimum water quality that is acceptable based on the
classification and uses of the surface water for a specific segment of the Alamosa River. .
At PreSent, segment 3b;fi.om umn~IY,aDcme:t1ie.carifluenceDf:Ih~.Alamosa River, - .
with Wightman Fork to ~e inlet of Terrace Reservoir, has the mo$t stringent water .
quality standards iIDniediately'downstream of the Site. Therefore, the segment 3b 'aquatic
life 'cold water quality standards are ARARs which have been utilized to calcula;te the
IALs, for the Site. Consequently, the water quality standards for Terrace Reservoir and
the segments downstream of the reservoir are not considered ARARs.
Comment 42:
Several commenters are concerned that all four of the FFSs contain a statement that none
, .
of these interim actions "is anticipated to produce and immediate reduction in
contaminated water flows." . This was interpreted as a "disclaimer" that would potentially
justify "letting out Remedial Contracts worth nearly 64 million dollars". In addition, this
"disclaimer" allows EPA employees to avoid accountability, and in cases where these'
, remedial actioDS are not effective, this statement is in direct conflict whit the published
'RAOs set by EP A. .
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fl.
Re~~mnse: . . .
The remedial actionS in the four FFS's are designed to address various sources of
contamin9ted waters at the Site in order to achieve a reduction in the generation of
contamin~ted waters (Remedial Action Goals). The Water Treatment FFS is designed to.
. treat the contaminated waters in the interim penod while these long-term remedial actions
are being implemented and are taking effect. The effect of this interim remedial action is
anticipated to be the first step forward compliance with the RAOs. .
~
Comment 43:
The Water Treatment FFS doesn't clearly identify the standards to be achieved in the
discharges from the water treatment systems. The specific interim. numerical standards
being applied to discharges from the Site should have been defined and consistently used
when evaluating and selecting an interim remedial action. .
R~nse:
The interim action leVels (IAL) for water quality given on page 23 of the Water
Treatment FFS are the standards used for the Site. The current Site operations meet the
levels established for the indicator compounds in effluent standards. These indicator
compounds, copPer and cyanide, are selected due to their similarity in chemical process
technology to the other compounds listed in the interim action levels. The IALs will be
formally included into the Site record and when the IRODs are ~roved and signed by
. the CDPHE and EP A. Compliance with the IALs will enable the Site to meet the
Segment 3b standards which are ARARs for the Site. .
The Water Treatment FFS based the evaluation and selection of the interim remedial
action on the IAL. In 40 CFR 300.430( e)(2)(i), EP A is directed to develop remediation
goals for the Site that are "protective of human health and the environment". The
considerations for the development. of thesesann3MS include;..l).'!ApplicableorRelevant
and Appfo~Ii~q~~ts (ARARS)"imderf"ederiif ~Viionmental or sttte' . ... - ... .
environmental or W;ili~ siting.laws"; 2) Water qwility criteria under Section 303 and
304 of the Clean Water Act; and, 3)EnviIonmental evaluations. The Code ofFedeml
Regulations continues in sub-p~hs (Ii) and (ill) to require the EP A to identify and
evaluate potentially suitable technologies and assemble these technologies into alternative
remedial actions. . .
~- ~..
The Water Treatment FFS follows the CERCLA guidance document for conducting
Remedial Investigations and Feasibility Studies, OSWER 9355.3-01, in uti1i7.i"g these .
standardS to evaluate the suitable technologies and assemble them into alternatives. These
technologies are first evaluated for implementability ( OSWER- Section 4.2.5) and, if
implementable, further evaluated as process options for effectiveness, implementability
and cost. The NCt and IAL were significant considerations in the evaluation of these .
. options for effectiveness ( see pages 43-56, Water Treatment FFS). Additionally, the
80
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effectiveness evaluation was used to screen the technologies once they were assembled
into alternatives (pages 60-64). Once the screening process Was completed, the Code of "
Federal Regulations specifies a detailed analysis of alternatives to be performed {40 CPR
300.430(e)(9)(iii)(B)}. The detailed analysis includes a section regarding ARARs
compliance. Each of the alternatives was evaluated for this criteria (see Chapter Five, pp.
66-79, Water Treatment FFS). Specifically, the Water Treatment FFS states on page 71,
page 74 and page 77 for Alternatives #4, #5 and #6, respectively-
'The ARARs associated with this alternative will pertain to chemical specific
requirements for water quality as expressed by stream use classifications and
associated numerical criteria. " " "
The numerical criteria used in this report are the Numerical Criteria Limits (NCL)
" .
established by the CDPHE with SCMCl and the IAL recently developed by Morrison
Knudsen Engineers. Each of the alternatives were eval~ed as to attainment of these
standards based upon alternative development. Based upon existing Site data, Alternative
#4 is estimated to attain this ARAR 90% of the time without containment. The "
technology and alternative 8nalysis for the preferred alternative shows that implementing
the containment option would prevent the release of non-compliant water by the use of
the storage capacity. Water contained will be treated and released once the technology- "
based treatment system is able to reduce CODt~m1nants to acceptable levels attaining
ARARs 100% of the ~e. The development of Alternative #6 (IROD Alt. #5) includes
the construction of a new waste water treatment plant "designed to treat all selected AMD
streams, in aCcordance with Site remedial action objectives" (pg.64, Water Treatment"
FFS). By definition, this alternative would meet ARARs through designed treatment
~ac~. "
Further defiirition'6fthe mterimnum~cal ~ has;been provi4ed:1>y~~e Colorado"
Mining Association (CMA) in the recently published Conceptual Restoration Pi-Ogi-ani.""' ""
On page 4-11 the CMA writes; " " " "
"Revision of the water quality standards and/or classifications are necessary to
"revise NCLs or permit effluent limitations. Both the NCLs and the effluent
limitations provided in the CDPS permit for the water treatment facility are
determined using a mass balance equation utilizing Alamosa River water quality
standards. Also, the water quality standards would, under most circumstances
may (sic) be considered ARA.Rs for purposes of a cleanup performed pursuant to
CERCLA." " " "
"w at~r quality standards for the relevant segment of the Alamosa River (Rio
grande Basin segment 3b) would be used for determining the NCLs or permit
effluent limits."" .
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"
The CMA also comments within the same document:
- ''lft!ze NCL concept is utilized as part of the cle~'ofthe Site, the NCLs may
. need to. .be recomputed The NCLs reportedly were based on CDPS methodology .
. for water quality b~ed effluent limitations and were calculated uSing the
conventional mass balance calculation. Alamosa River flows, background
concentrations, and water quality standards were believed to be used in the mass
balance equation (Golder, 1992). However, since the NCLs were calculated, the
Rio Grande Basin has been resegmented, reclassified, and different water quality
standt:lrds have been assigned to the relevant portions of the Alamosa River and
the Wightman Fork. Some of the standards have become stricter than at the time
the NCLs were calculated, while others are much less stringent (e.g. silver). "
While EP A does not necessarily agree that every relevant segment within the Rio Grande
Basin has been revised, it COIlCtD'S that the IALs should be established using this
methodology. In fact, the EPA utilized this methodology to set the IALs (see pg 23,
Water Treatment FFS). Since the IALs are based on the 3b surface water quality
standards, the IALs are 'Considered to be the water quality standards for the water .
treatment discharges at WF-S.S, the Site compliance point .
Comment 44: .'
Given the expenditures required to maintain the existing Site water treatment processes,
the Water Treatment FFS is incorrect in the conclusion that effective water treatment
facilities exist on-site and the need for capital investment for water treatment facilities does .
. not exist. Sufficient development of alternatives was not performed for the alternatives
screening and several alternatives presented in Section 3.0 merit further development. The
Water Treatment FFS implies.that current treatment facilities meets the Colorado'
. Discharge Pe~t S~dards. ..Bo",ever, monitoring.is~per.formed fOJ:.only. two:indicator'. .
metals, while EPA has conveniently ignored the other panuDeten that were ciiflicuiior'-~. .. .
. virtually impossible for prior minen to meet. Therefore, the Water Treatment FFS must
be considered incomplete. .
R~onse: .'
One commenter suggested that the Water Treatment FFS is incomplete because the
..effectiveness of the existing water treatment systems is inconclusive~ As stated earlier, the
success of the existing systems is deemed sufficient to warrant favorable dispensation
from EP A in an effectiveness analysis. The commenter also states thai it is unfair to hold
prior miners responsible for treatment parameters different than standards currently being
met by EP A EP A is under the same substantive requirements as the former operators.
These standards are identified in the ARARs section of the Water Treatment FFS. EPA
has made significant improvements in ~tt~;n;ng these standards. Upon formal signing of
the IROD for Water Treatment, these standards, as set forth in the IALs, will become
. .
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treatment goals for this interim remedial action. Finally, EP A finds that the use of the
IALs did not preclude the analysis of potentially labor or cost reducing processes at the
Site. Because all technologies were evaluated using the same criteria, an technologies
were analyzed within the Water Treatment FFS using the potential for metals recovery
and subsequent O&M impacts. .
Comment 45:
Without establishing ARARs, EP A eliminated the use of biomass and ultrafiltration, more
effective alternatives, since its existing practices are essentially "good enough" for now.
. Electroplating was eliminated because the currently used technology does not produce a . .
concentrated liquid waste stream. The Water Treatment FFS should have considered the
possibility of modifying current treatment processes so there would be a concentrated
liquid waste stream acceptable for electroplating and metals recovery. .
R~onse:
S~ly, another commenter noted that biomass, electroplating, and ultrafiltration were
eliminated without establishing ARARs and therefore were eHminated without a
standardized effectiveness evaluation. It is important to note that two of these
technologies, biomass and ultrafiltration, were defined in the Water Treatment FFS as
polishing steps. The third technology, electroplating, would require substantial capital
investment and realignment of process technologies to implement at the Site.
Consequently, EP A did not consider these technologies effective based upon the apparent
marginal, additional treatIIient effectiveness resulting from significant development and .
.implementation costs. As disCussed earlier, EPA has identified ARARs in Section 3.2 and
Appendix C of the Water Treatment FFS. All technologies and alternatives were
evaluated using.these standards. As a matter ofprocedme EPA does not "eStablish"
. ARARs; Iather,EPA is required"to meet.or Y.tcUve the'existing.~ 'at the..Sit~.. The
CMA has provided EP A with the industry perspective on the procedures used to .
"establish" ARARs at the Site in Section 4.4.2, Restoration Goals,-CMA Conceptual
Restoration Program. While EP A does not endorse or support the CMA proposal to
revisit.the ARAR.standards, it emphaSizes the fact that the EPA CERCLA remedy
selection process is quite different than the establishment of ARARs. .
Comment 46:
The Water Treatment FFS imp~es that interim remedial measures that do not fully meet
interim water quality numerical standards may be acceptable provided the ARARS waiver
provision is applied. The waiver of ARARs provision or its use in this instance is not
adequately addressed relative to its potential impact on the selection of a preferred
alte.rnative and t~e final remedy. "
. -.
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R~onse:
The Water Treatment FFS does not imply that a waiver under 40 CFR
, 300.430(f)(1)(ii)(C) will be sought or granted pursuant to the selection of this remedy.
EP A believes that the preferred alternative meets the IALs and, therefore, is comp~t '
with the ARARs at this Site.
The section of the Water Treatment FFS that apparently caused confusion evaluates the
different alternatives based on the nine criteria in the EP A RIlFS guidance document.
Compliance with ARARs is one of the nine criteria. EP A included the waiver '
applicability analysis as part of this evaluation and does not intend to exercise this
process with this remedy. '
- . .' .
Comment 47: .
The concentrations of the majoritr of the COC identified by the EP A are not presented in
the report. Also, cleanup standards for these contaminants are Dot clearly identified. It is
difficult to determine If any of the evaluated alternatives are effectively remediating the
COC.
, Re~onse:
Page 28 of the Water Treatment FFS states "Copper and cyanide were targeted
Contaminants of Potential Concern (COPC) for monitoring and control during
Emergency Response water treatment actions. These chemicals were the COPC with the
highest concentration in residual process water and AMD ftom disturbed areas." During
the transition ftom an Emergency Response Removal Action (ERRA) to a Remedial '
Action the Data Quality Objectives of the sampling and analysis program were primarily
focJ1Sed on water treatment process evaluations to further refine system effectiveness, to
increase protectiveness to downstream receptors through higher quality water effluen~
. and to reduce treatment costs~,~me.,wide spectrum-analysis--waS.initi~y perfOI'I]:1ed by
Ecology and Environment downstream of the Site. Cmrently, all of these COPC ar,e,
being monitored as part of the Sitewide Remedial InvestigationIFeasibility Study (RIJFS)
being Completed by Morrison Knudsen Engineers.
, .,
The technologies and altemativ~ were developed and evalUated using available mdustry ,
process information, Site characteristics, ARARs identification and other requirements
for a Feasibility Study under CERCLA., The additional COPC were included in the
evaluation inaSmuch as the interim remedial goals, as expressed in the IALs, identified
the contaminant as part of this interim remedial action. The COPC not ,covered in this
analysis are currently being ,evaluated in the RIlFS. This is consistent with the CERCLA
process. The results of the on-going RIfFS process will incorporate the environmental
evaluations of the other COPC. If, at that time, the COPC are not considered a threat or
potential threat to public health or the environment (42 USC 9604), then the COPC will
be deleted ftom the final ROD for the Site.
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EP A will not incorporate the COPC as chemicals to be treated on-Site without support to
identify the threat as defined by the CERCLA statute. EP A feels that this would be a
misuse of Fund money and; therefore, did not include the parameters which were not
clearly identified in the chemical-specific ARARs: 1bis discussion in the Water
Treatment FFS can be found on page 23.
Additionally, EP A believes that the five year interim period of water treatment
specifically identified in the Water Treannent FFS is consistent with possibly more
stringent requirements which may be set in the final Site remedy and, therefore, is
. consistent with CERCLA. . The proposed interim remedial action can be modified to treat
. additional cont:rminants, if necessary. . - . . .
Comment 48:
Table 8 in the Water Treatment FFS lists technologies and process options that are going to
be included as part of the detailed analysis of alternative. ~ table includes metabolic
biological processes for cyanide destruction, carbon adsorption, and wetlands treatment.
. However, Section S.O, Detailed Analysis of Alternatives, does not include detailed
discussions of these alternatives. .
Re~onse:
Another commenter found Table 8 confusing in because it identified biological treatment
for CN destruCtion, carbon adsorption and construeted wetlands for further evaluation yet.
these options did not appear to be included in the Detailed Analysis of Alternatives. EP A
wishes to clarify this table. The biological treatment option was applicable to the Heap
. Leach ~ad FFS and this analysis is found in that document. Carbon adsorption was on-
going at the time of Water Treatment FFS development. This technology was eval~
in Alternatives #4 and #5 Ss.pait.of eXistingWstems~The~developmen~ of the constructed
wetlands technology was incorporated into the Cropsy Waste Pile FFS due to the. .
restoration of the footprint areas being directly associated with the removal actions under
this operable unit.. The detailed analysis of this technology can be found in this document.
. .
..
Comment 49: ..
Interim water quality standards and the interim discharge monitoring point should be
selected in conjunction with the potential water quality standards and discharge
monitoring point for the final site remedy. Significant cost savings may be possible if the
costs associated with interim remedial action objectives are applicable to the final remedy.
Review of the detailed analysis of alternatives presented in the Water Treatment FFS
indicates that the interim remedial action time fra~e extends up to the year 2000 with
significant cost associated with the interim remedial action. In view of this, it is imperative
that the Water Treatment FFS consider the potential requirements of the final remedy so
that cost savings may be realized. For example, a new water treatment plant will likely be
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required for the final remedy since.the existing water treatment processes may not be
adequate with regard to design, operability, winterization, and flow rates. Therefore,
continuing to operate the existing water treatment processes in lieu of constructing a state- .
, of-the-art water treatment plant may, in the long run, not be a cost effective remedy.
R~nse:
The EP A established the IALs based upon ARARs for'the Site. The IALs are water
quality values which, if met, will assure that surface water flows ftom Wightman Fork
will meet the Segment 3b water quality standards for the Alamosa River at monitoring
point 45.4. The interim action period established by the EP A is five years. The IALs
will be used to monitOr the compliance with ARARs during this period. The interim
water quality standards are a benchn¥u'k for measuring the success or failure of the
interim remedial actions that take plac~ on-site; they are a stepping Stone to achieving the
final RAOs. The NCP is clear about using fixed ARARs during the CERCLA process.
In the February 6, 1990 Federal Register, Final NCP Rule, EP A writes on page 260:
"Once a ROD is signed and a remedy chosen, EP A will not reopen that decision
unless the new or modified requirement calls into question the protectiveness 01
, the selected remedy. EPA believes that it is necessary to 'freeze ARARs', when
the ROD is signed rather than at initiation 01 remedial action because continually
changing remedies to accommodate new or modified requirements would, as
several comments stated, disrupt CERCLA cleanups, whether the remedy is in
design, construction, or in remedial action. Each 01 these stages represents
significani time and financial invest11ients in a particular remedy. For instance, .
. the d~sign 01 a remedy (treatment plant, landfill, etc.) is based on ARARs
identified at the signing 01 the ROD. If ARARs were not frozen at this point,
promulgation 01 a new or modified requirement could result in a reconsideration
. 01 the remedy and are-start 01 the lengthy design process, even if protectiven,ess
, is..not compromised. -:Thislack. ojCllt:ttlimy eouId'~rsely qffect the oper.a!fon 01
the CERCLA program, would be inconsistent with Congress' mandate to
expeditiously cleanup sites and could adversely. affect PRP negotiations, as staled
in several comments. The policy 01 freezing ARARs will help avoid ,constant
interruption, re-evaluaiion, and re-design during implementation 01 selected
remedies. ". "
"EP A believes that this policy is consistent with CERCI4 section 121 (d)(2)(A),
which provides that 'the remedial action selected...shall require, tlllbJ:.
comlJletion 01 the remedial action,' attainment 01 ARARs. EP A interprets this
language as. requiring attainment 01 ARARs identified at remedy selection (i.e.,
those identified in the ROD), not those that may come into existence by the
completion 01 the remedy...:Neither -the explicit statutory language nor the
legislative history supports a conclusion that a ROD may be subject to indefinite
revision as a residt 01 shifting requirements. Rather, given the need to ensure
.
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finality 01 remedy selection in order to achieve expedit!ous cleanup 01 sites, and
given the length 01 time often required to design, negotiate and implement
remedial actio1f:S, EP A believes that this is the most reasonable interpretation 01
the statute." . ..'., " .
The discharge monitoring point WF-5.5 will remain the interim monitoring point for the
Site and the IALs will remain the interim water quality standards during this remedial
action five year period. . .
Additional comments were received regarding the use of existing facilities rather than
, building a new treatment plant at this time. The comments 'stated that building a new
., plant now would Start the amortization process of the new plant costs. The underlying
premise is that a new plant ~ eventually be required to meet ARARs, so it may as well
be constructed now.
EP A's believes that a new plant will not be required unless Site source control actions
(i.e., Reynolds Adit plugging, Cropsy Waste Pile Removal, Mine Pit Restoration; Heap
Leach Pad Capping) are unSuccessful. Since these control measures are utilizing proven
teChnologies in the mining industry,' EP A is confident that ARARs compliance may
, 'indeed be achievable in five years without continuation of active water treatment.
The purpose of the comparison between Alternative #5(IROD Alt. .#4) and Alternative #6
(IROD Alt. #5) in the Water Treatment FFS is to evaluate these two options using
CERCLA criteria. ~CLA criteria include cost analysis. Alternative evaluations can be ,
found in Chapters Four and Five of the Water Treatment FFS, pp. 58~83. .
EP A believes that once protectiveness is achieved at the Site through source control'
actions, the use' of the existii:1g'\wteitteatmeIit facilities wnfbecome'unnecessary. ThiS is'
consistent with the fourth and fifth Remedial Action Objective established by EP A and
listed on page 32 of the WatJ:r Treatment FFS, as follows: ..
.
to reduce or eliminate the need lor continued expenditures lor
water treatment at the Site; and .
.
to encourage early action and acceleration 01 the Superfund
process.
.
The Colorado Mining Association wrote about this approach in the Conceptual ..
Restoration Program recently submitted to the EP A. On page 4-2 in Work Element No.2
of the proposed Site Management Implementation Program (SMIP) the CMA dlscusses
. oprim;7ing.the existing systems at the Site: .
. . ,
"One goal 01 the SMIP is to optimize the performance 01 the water treatment
87
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systems that are in place. It is often" more cost effective to improve the
" performance of an existing treatment plant than it is to expend additional capital
for a new one. This concept and philosophy has bee';" adopted by EP A and their.
-." contractors. This is particularly true when the plant is expected to have a short "
operating life (and thus, a short 'pay-back' period). At this time, it is premature to
spend new capital for new water treatment systems without first having optimized
the existing systems and without knowing the operating life of a new system. "
The EP A concurs and has performed this analysis. Starting in December, 1992 EP A
utilized Environmental Chemical Corporation, Weston, and Ecology and Environment to
evaluate and optimize the existing water treatment systems. Additional support was
. - provided by EP A Region vm Mine Waste Management and Water Quality personnel,
. CDPHE and Department of Natural Resources experts, and the EP A REAC Team from
Deepwater, New Jersey and Cincinnati, Ohio. Immediate and significant changes were
made to the water treatment processes as a result of the evaluation. "
Additional support was requested from industry in March of 1993 through a Request for
Proposal (RFP). The RFP was sent to 120 industry leaders in water treatment. The .scope
of the RFP was enhancement or improvement of water treatment operations at the Site.
EP A received 23 responses some of which are cwrently being adopted. Other proposals
are still under consideration. . .
For more information on water treatment processes, refer the to the EP A REAC Team
Report compiled by Weston (February, 1993), the RFP by Environmental Chemical
." Corporation (March, 1993), the Task# 14 Report by Morrison Knudsen Engineers
(February, 1994) and the Project Report for the USBR by ECC (July, 1994). These
documents are available in the EP A Administrative Record, refer to Section 2.1 for
locations. cUrrently, evaluation reports are being generated by Dames and Moore and
Morrison Knud$en pn ~er considerations iot..water_treatmeDt.improy.eID;~." - .
..' ." .' '.. . l .
Comment 50: .
The Water"Treatment FFS should describe the specific improvements that were made to
the CDP and MRP. (S~CtiOD 2.1)
Re$pOnse: -" . .
Changes that were made to the CDP and MRP were done under the ERRA. The future
modifications that will occur during the interim action will be discussed in the 90%
design doctunent.
.
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Comment 51: .
. The Water Treatment FFS does not include process flow diagrams nor does it adequately
. describe the water treatment process being used at the CWTP, CDP, and the MRP. Also, it
does not provide adequate detail regarding the interaction of the various water treatment
plants aitd other Site facilities such as the French Drain Sump.
Re51)onse:
The Water Treatment FFS presented the targeted treatment streamsin Chanter 3, pp.36-
38. It is beyond the scope of the FFS to include Process Flow Diagrams (PFD). 'PFD are
provided in the Administrative ~ecord within Water Treatment FFS supporting
documents. . The Water Treatment FFS was prepared and reviewed by personnel with
extensive knowledge about the on-going treatment processes at the Site. The Water
Treatment FFS did incorporate the existing interactions between water treatment facilities
in its development of alternatives. The comparison between Alternatives #4 and #5
(lROD Alts. #3 and #4) provides detail regarding the interaction of the water treatment
, plants. Alternative #4 utilizes both the CDP and $e MRP for the entire remedial action
period. Alternative #5 e1imin~tes the need for CDP and MRP interaction after HLP
detoxification activities are completed. Thus, EP A has proposed the elimination of the
MRP in late 1996. EPA and State evaluators with substantive Site process knowledge
concur with this approach. Please refer to the alternative analysis sections of the Water
Treatment FFS, pp. 32-81. .
EP A directs the commenters to the RFP sent to industry in March 1993 by Environmental
Chemical Corporation. This document contains detailed process descriptions as well as .
PFD. During this RFP process the proposers were given tours of the facilities wherein
, engineers were able to no~ only review comprehensive, full-scale PFD, in great detail, but
also were able to inspect the processes at the Site. EP A still provides interested parties
withSitetours...-- -....:;. ..'" ,"q' ,'" .".,. , .
. . ~. . . -,"'...."- .' ..' 'r 0, ""'" .
Comment 52: .
The Water Treatment FFS does not provide decision makers with sufficient information to
,adequately compare the possible, alternatives. Additional information required includes
clearly defined emuent standards~ flow diagrams of the proposed alternatives, more
thorough development of options that offer a true alternative to existing water treatment
processes, more detail and support documentation of cost estimates, and more discussion
justifying the preferred alternative. '.
.
Response:' ,
EP A addresses the process of providing sufficient information to decision makers in the
"Guidance for Conducting Remedial Investigations and Feasibility Studies Under
CERCLA", OSWER Directive 9355.3-01, Section 4 and 6 as follows: '
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,
'The FS may be viewed (for explanatory purposes) as ocC7l1Ting in' three phases:
the development of alternatives, the screening of alternatives, and the detailed
analysis of alternatives....
"Alternatives for remediation are developed bY iusembling combinations of '
technologies, and the media to which they would be applied, into alternatives that
address contamination on a sitewide or for an identified operable unit."( pg.4-3)
, ,
The Water Treatment FFS presents the alternatives for Water treatment in Section 3.4,
General Response Actions and states:
... .
. '"General Response Actions are measures to satisfy the interim RAOs. The
. general response actions may be used alone or in combination to provide the most
appropriate remedial action alternatives. The general response actions for
consideration in meeting contaminant transport minimization or elimination
consistent with remedial goals during Interim Remedial Action for water
treatment are:' ,
.
.
No Actipn
Institutional Controls
Containment
Active Treatment
Passive Treatment"
.
.
.
The OSWER Directive continues...
. "Identify and screen the techlzologies izpplicable to each general response action
to eliminate those' that cannot be implemented technically at the sjte... "'
, '
.. . " .
"Ide1ztiJy and evclJuate tecJmology process options 'to select ti rejJ~esentative '
process for each technology type retained for consideration. Although specific
processes are selected for alternative development and evaluation, these
processes are intended to represent the broader range of processes within a
general technology type. " (pp 4-4 and +-5) "
, '.
The Water Treatmept FFS addresses this requirement in Section 3.5, Identification of.,
Water Treatment Process Technologies, pp 40-43. In this section the Water Treatment
FFS evaluates oxidation, neutralization/precipitation, b~ological treatment, separation,
electrochemical treatment, constructed wetlands, 'anoxic limestone drains, land
application, sedimentation, and evaporation. Much of the data used to evaluate these
technologies came from proposals from industry sources for the Summitville Site
received in response to the March, 1993 RFP. The RFP presented a thorough and
complete representation of exis.ting and developing technologies. Where necCssary, the
.
90
-
. . ~ .
. ,.,,' .'. "
. ......", .. .".
--"'_'n ........~-.--:' .
. .. - ...
, ' ,
.. "........... .-'... .
-------
,
RFP database was supplemented by literature and vendor source searches. The remainder, .
'of Section 3 presents the evaluation of the technologies which led to the development of
the alternatives in !be Water Treannent FFS. .
. '
The OSWER Directive continues...
"Alternatives are defined during the development and screening phase (see
Section 4) to match contaminated media with appropriate process options...
However, the alternatives selected as the most promising may need to be better
defined during the detailed aTl4lysis. Each alternative should be reviewed to
determine if an additional definition is required to apply the ~aluation criteria
consistently and to develop order-of-magnitude cost estimates (i.e.~ having a
desired accuracy 01 +50 percent to -30 percent). " (pg. 6-4)
The Waw Treatment FFS provides these additional definitions in Section 4.3, Screening
of Identified Alternatives (pgs.60-64). Further application of the nine CERCLA criteria '
for theSe alternatives is provided in Section 5.0 (pgs. 65-81). EPA has determined that
the level of information provided to decision-makers is sufficient to meet these criteria
~d adequately justify selection of the preferred alternative. '
Comment 53:
Alternative #6 includes construction of a new treatment plant; however, no details are
provided regarding the proposed treatment process, plant capacity, or its loeation. .
Response: .
, A cominenter was concerned about the apparent lack of det8i1 in describing the pro~sed
treatment plant in'Alternative #6'. 'J'he~W~re~~nt-fF~~eribes the alte~ve in
Section 4, page 64. EPA believes that for the purposes of the CERCLA ievefofdesign .
considerations (Le., +50% and -30%) this description is sufficient to meet these
parameters. EP A would like to ,explain to the commenter that. this comparative cost
analysis will be tiTla1i7.ed for the selected remedy in the remedial design phase..
Alternative #6 design considerations will ~. p~ented m following reports.
.' .
. '
'Several potential technologies were identified through the RFP process for'application at
the Site. All of these technologies would be ,considered for an actual design for the plant.
The maximum plant capacity estimated for Alternative' #6 is 2,000 gpm.
-
Comment 54: . ,
Alternative #S proposes annual operating costs that range from $7.20 to $34.00/1000
gallons. These.costs are very high compared to typical costs for
neutralization/precipitation using sodium hydroxide, which tYPically range from 51.50 to
91
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~
52.50/1000 gallons. EP A must provide an explanation why Site costs for
neutralization/precipitation are so high. .
. Re~onse: . . . .
EP A received additional comments regarding the adequacy of the cost presentation in the
Water Treatment FFS. The cost analysis included capital costs inclusive of construction
costs, equipment costs, land and site-development costs, building and services costs,
engineering expenses, startup costs and shakedown costs, among others. Operating and
Maintenance (O&M) costs in this analysis involved calculating operating labor costs,
maintenance materialS and labor costs, auxiliary materials and energy expenses, disposal
of residues, purchased services, administrative costs, insurance, taxes, and licensing costs,
maintenance reserve and contingency funds, rehabilitation costs, and costs of periodic site
reviews. Furth~ definitions of these costs categories can be found in OSWER Directive
9355.3-01, Guidance on Conductine Remedial Investieations and FeasibilitY Studies
Under CERCLA. pp.6-:-11 and 6-12. Additionally, EPA believes that the placement of
Site maintenance and support costs into the Water Treatment FFS interim remedial action
is appropriate because the primary reason Site access is required during the long winter
season is to continue water treatment activities.
One commenter requested clarification of process demobilization descriptions. EP A
Qirect:s this commenter to Table 10, Cost Est1mflte for Alternative #1, Total Capital Costs.
This section of the table identifies the specific mothballing activities, timeftame and
costs.
. .
Another commenter requested cost data on Site support activities as developed in the
Water Treatn1ent FFS to evaluate whether these numbers artificially skew the results to
. the preferred remedy. The Site support cost data for Alternative #4 was developed using
actual pumbers from on-going site activities. The Water Treatment FFS alternatives #1
. and #3 include Site suppo~ costs ~~tiaUy.lo~.~ the preferred alternative (see.
. Tables 10,11, and 12). EPA directs thi$commenter.to-MS. Laura Williams at (303) 293"-""
1531 to obtain copies of monthly cost numbers.
. .
Comment 55:
The Water Treatment FFS states that "the cost evaluation focuses on comparative
estimates rather than specific and detailed analysis." Costs of the magnitude of Alternative
#5 (527 million) require specific and detailed analysis to justify the selection of the .
preferred alternative. .
Re~onse: .
A commenter felt that the cost analysis provided in the Water Treatment FFS should not
have been based upon "comparative estimates" due to the magnitude of cost associated
with the preferred alternative. EP A believes that it is appropriate to use comparative
.
-------
,
analysis to evaluate the relative costs for alternative analysis. There are three separate
cost analyses stages within the Water Treatment FFS. Initially, technology process option
. costs were compared in Section 3.0. This analysis is described on page 43 of the Water
, Treatment FFS: ' '
"CM!.: Cost is considered during the initial screening o[ process options based on
overall capital, labor, utility, and reagent estimates o[ cost rather than detailed
engineering cost estimates. "
The Water Treatment FFS further evaluates cost for developed alternatives in the
Screening and Detailed Analysis of Alternatives, Sections 4 and 5, pp.60-81. The
screening of alternatives in the Water Treatment FFS Section 4 did not use a detailed
analysis of costs.. The result of this preHminary screening was the eHmination of
, Alternative #2, Institutional Controls. However, it is important to note that in the Detailed
Analysis of Alternatives, Section 5, detailed, actual Site costs were used to develop a coSt
category estimate wherever possible. The third and final cost analysis occurs in the
selection of remedy cUlTeI1tly underway with the Proposed Plan for Water Treatment. In
this step all of the nine criteria, including cost, are factored and balanced to evaluate ~e
alternatives for an interim remedial action plan. The Final Rule of the NCP (February,
1990) discusses this process in greater detail on page 164: .
"Many commenters reflected some confusion over the rqle o[ cost as an analytical
,criterion under the detailed analysis and the required statutory finding that the
remedy be cost-effective. One commenter focused on the need to distinguish the
cost efftctiveness finding from the cost evaluation criteria. EP A agrees that this
distinction is an important one. Although cost is used as a crude screen' in the
development and screening 01 alternatives, cost is primarily addressed in the
. detailed analysis and.remed;J. selection.phases. ofJhe.r..emedial process. ,The
detailed analysis evaluates Cirid comPares tHe 'cost of the 'respective "alternatives; . -,"
bUt draws no conclusion tis to the cost-effectiveness o[ the 'alternatives. Cost
efftciiveness is determined in the remedy selection phase, considering the long-
term efftctiveness and permanence afforded by the alternative, the extent to which
the alternative reduces toxicity, mobility or volume 01 the hazardous substances
through treatment, the short-term effectiveness o[ the alternative, and the '
alternative's cost..~" ,
...
Comment 56: .. ,
The alternatiVes in Section 4.0 appear very similar. It appears that little or no effort has
been made to identify any creative and/or innovative alternatives for further evaluation.
Response: . .
. A commenter stated that the alternatives which were identified in the Water Treatment
-------
"
FFS did not include any creative or innovative alternatives for further evaluations. EP A
wants to assure the commenter that creative and innovative technologies were evaluated
in Section 3 of the Water Treatment FFS, specjfiCauy in the alternatives screening and
development process. The inclusion of the biological treatment option in alternatives
within the Heap Leach Pad FFS (see Table 8, Water Treatment FFS) is one result of this
process. Development of constructed wetlands in the Cropsy Waste'Pile'FFS is another
, example of emerging ,technology applications at the Site. Inasmuch as EP A included
teChnologies from the screening into the Alternatives Development step, EP A explains
how innovative technologies are to be evaluated in the CERCLA process in the Final
NCP Rule, pg 142: .
"EP A would like to clarify that it does not intend to inhibit the development of
" innovative technologies in the development and screening of altematives~ EP A
has deleted the requirement in the final rule that innovative technologies lrrust
offer "better" perfOrmance than proven technologies. Instead, EP A has stated its
intent to consider those innovative technologies that offer the potential for
comparable .or superior performance or implementabi/ity; fewer or lesser adverse'
impacts than other available approaches; or lower costs for similar levels o[
performance than demonstrated treatment technologies. By providingfor the
consideration of innovative technologies, EP A intends to, eliminate from
consideration only those innovative technologies that have little potential for
performing well at specific sites.
, .
"As part of the encouragement of innovative technologies that EP A expects to
result from this provision, EP A is emphasizing the need for performing
treatability studies earlier in the remedial process. "
EP A began treatability studies on biological treatment of detoxification of the Heap
Leach Pad. Additional treatability snidi~ IJa.v~ ~~ perfo.~~ 0]1 biocides, reagent
substitutions, 1iiDeStone, lime, 'lime' kiln dust, -and 'cement 'kiln 'dust:'EP A haS 'complied
with the CERCLA requirement for innovative technologr development and continues to
support this development in Site operations.
Comment 57:, , , ,
Alternative 3, 4, and 5 include the CWTP in the alternative description; however, the '
CWTP is Dot included in the costs of the alternatives.
R~nse:' ,
One commenter was unable to locate the CWTP costs in the Water Treatment FFS. The
CWTP costs are incorporated into the Cropsy Waste Pile FFS an3.Iysis. Please reference
this document for this data.
.
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..-.--.-.
,
-----'--'- ....
, Comment 58:
Insufficient backup is provided to perform a thorough review of the adequacy of the
alternatives' cost estimate presented in Tables 10 -14. For example: '
+
The Water Treatment FFS does not adequately define capital and
O&M costs. .
Process demobilization needs to be described and backup information
provided.
All alternatives were developed assuming the same level of support.
The costs associated with weekly monitoring seem excessive (te., ,
,'$5~,640.00Iweek). . . . - .; , .. '-. "
, Cost estimates for Alternative 4, 5, and 6 do not include weekly
monitoring. . '
Each alternative includes costs associated with current Site operations
and costs may artificially favor the status quo.
+
+
+
+
+
Res.ponse:
EP A received additional comments regarding the adequacy of the cost presentation in the
Water Treatment FFS. The cost analysis included capital costs inclusive of construction
costs, equipment costs, land and site-development costs, building and services costs,
engineering expenses, startup costs and shakedown costs, among others. Operating and
Maintenance (O&M) costs in this analysis involved calculating operating labor costs,
maintenance materials and labor costs, auxiliary materials and energy expenses, disposal
of residues, purchased-services, administrative costs, insurance, taxes, and liCensing costs,
maintenance reserve and contingency funds, rehabilitation costs, and costs of periodic site
, reviews. Further definitions of-these costs categories can be found in OSWER Directive'
9355.3-01, Guidance on Conductine Remedm,tInvestieations and Feasibility Studies
: . 'Under CERCLA . pp.&-11 and ~12: Additionally; BfA believes-tbat1heplacentent"()f". . .~ ,"
, Site maintenance and support costs into the Water Treatment FFSinterim remedial action
is appropriate because the primary reason Site access is required during the long win~er
season is to continue water treatment activities. .
One commenter requeSted 'clarification of process demobilization descriptions., EP A .
directs this commenter to Table 10, Cost Estimate for Altemative #1, Total Capital Costs.
This section of the table identifies the specific mothballing activities, timefranie and
costs.
, .
Another commenter requested cost data on Site support activities as developed in the
Water Treatment FFS to evaluate Whether these numbers artificially skew the results to
the preferred remedy. The Site support cost data for Alternative #4 was developed using
actual numbers from on-going site activities. The Water Treatment FFS alternatives #1
and #3 include Site support costs substantially lower than the preferred alternative (see
Tables 10,11, and 12). EPA directs this commenter to Ms. Laura Williams at (303) 293-
1531 to obtain copies of monthly cost numbers. ' .
.
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"
. Comment 59: . .
It is not clear how Alternative #4 accounts for the increaSe hi treatment capacity of the
CDP and MRP from 600 gpm to 1000 gpm without significant capital expenditures to
improve plant capacities or without significantly degrading treated emuent quality. Since
current operation requires that both the CDP and MRP be operated in series. to meet
discharge standards, the Water Treatment FFS should explain how discharge standards
c:an be met with only the CDP in operation. .
R~onse: .. . . .
Several eommenters expressed concerns regarding the effectiveness evaluation of
Alternative #4. Commenters questioned the ability of the CDP to reduce contaminant
loadings in the discharge effluent to the Site standards and the ability of the containment
feature to control peak flows. Additionally, one commenter addressed the cost and design
considerations of the new containment feature. EP A believes that once the ~P is
detoxified, the conversion of CDP would result in the highest treatment capacity available
at the Site to treat the AMD water which is stored in the containment structure. .
Elimination of the MRP would be desirable due to its lower throughput capacity and
overa1lliigher operating cost per gallon of treated water. The CDP can be converted to
AMD treatment once the requirement for cyanide treatment is eliminated through closme
of the HLP. The Watf:r Treatment FFS explains this premise on pages 62 and 63 in the
alternatives description. The MRP adds approximately 400 gallons per minute of extra
treatment capacity to the proposed Al\tID treatment system at a cost of over one half a
. million dollars per year or S2.5 million over the five year period (Table 12). EP A
believes it is more effective to construct a containment structure (Appendix D) at a cost
of S 1.6 million (See page 76, Water Treatment FFS) than to continue using the MRP.
. The containment structure volume calculations are included in the stnictuIal descriptions. .
Cost facto~ for the. ~J:age .~n~~!,f~ 9!.~~cJude: esti~~t~.for new routing
systems. The containment structure would have-considerable-advantages in that its long.;
term effectiveness and permanence would far exceed the interim remedial action period
for the same amount of cost whereas the MRP would require continued expenditures ~f
cash to maintain its long-term eff~veness. Whereas, the use of the MRP would not be
permanent
Comment 60: . . .
ne interim remedial action objectives do not focus on quantified cleanup standards nor do
they provide consideration for remedies that are highly reliable, cost effective, and
protective of human health and environment. ne study does not provide sufficient
information to adequately compare the alternatives to support an informed risk
management decision for selecting an Interim Record of Decision (IROD).
.
.,
96
...
-
..
'.-.:-:- .'
. "- ..'~.~~"~
. .- ...... ...
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_.~- -- .. ..-.--
.,-----. - . -. ~----_._--""'~
.. -..'''' .'.........'-..:.._--
'~
.
. Re$,ponse:, ,
One commenter expressed confusion regarding the use of the Remedial Action
Objectives and the Focused, Water Treatment Remedial Goals as identified in the Water
Treatment FFS (page 32). Specifically, the comment stated that the Interim RAOs (sic) .
do not focus on quantified cleanup levels nor do they support an informed risk
ro::rn::rgement decision for selecting an !ROD. 'EPA disagrees with this assertion. The
sitewide activities include stabilization actions which remove the waste rock from the
water. In the case of the CWP, this action has been very reliable in terms of risk
reduction' by isolating the AMD rock from seeps and springs withjn the Cropsy drainage
basin. Likewise, the Interim Remedial Goals listed in the Water Treatment FFS include
, .
"reduction of conmm;n::rted water impacts to the aquatic receptors in the Wightman Fork,
the Alamosa River and the Terrace Reservoir during interiM remedial activities"(Water
Treatment FFS, pg.33). As discussed earlier, this risk reduction criteria is based upon the
ARARs (segment :3b of the Alamosa River) used to set the IALs. .EP A believes that this
process adheres closely to CERCLA and, thereby, provides criteria for consideration of
remedies within the Water Treatment FFS that are highly reliable, cost effective and .
protective of human health and the environment The Final NCP Rule promulgated in
FebIUary of 1990 addresses this issue on page 138:
, .
. .
"In fact, remediation objectives and goals are initially developed at the workplan
stage, prior to commencement of RUFS activities. In addition, the remediation
goals are not necessary for the baseline risk assessment: . Rather, the results of the
baseline risk assessment are used to confirm that the preliminary remediation
goals are indeed protective or to lead to the revision of the remediation goals in
the proposed plan...
'The remedial ac!ion objectives an the more general description of what the
remedial action objectiVe' wi/l'iiCcompliSh...:,$eniediatiozigoals are a.sUbsetlJf.... '~ " .
remedial action objectives and consist of medium-specific or operable unit- '
specific chemical concentrations that are protective of human health and the
environment and serve as goals for the remedial action... ".
, .
"As noted aboile, the preliminary remediation goals are the'more specific
statements of the desired endpoint concentrations or risk levels. Initially, they are
based on readily available information, such as cheinica[:-sPeclflc ARARs (e.g.,
MCL, WQC) or concentrations associated with the reference doses or cancer
. potency factors... " .
..
'The development of preliminary remediation goals serves to focus the
development of alternatives 0" remedial technologies that can achieve remedial
goals, thereby limiting the number of alternatives to be considered in the detailed
.analysis. This focusing is one means of implementing the program's expectation.
for streamlining the remediation process. Information to develop final
-------
"
remiJdiation goals is developed as part o[ the RUFS process. Consequently, the
use o[ preliminary remediation goals does not preclude the development and
consideration or selection o[ alternatives that attain other risk levels. Final
. selection o[ the appropriate levelo[ risk is made based on the balancing o[ .
. . criterlain the remedy selection step o[ the process. n. .
,.
Comment 61: '.
Alternative #4 (IROD Alt. #3) states that peak flows in excess of 1000 gpm would Dot be
treated. The Water Treatment FFS should provide and estimate of the total quantity of
water that would no be treated during a normal precipitation year. This information is .
necessarY to assess the impact to water quality relative to Alternative #4 (IROD Alt. #3).
. .
. . Re~OIise:
SeveralriQmmeri.ts were received about the Alternative #4 evaluation. AlteInarlve #4
would result in flows which exceeded 1,000 gallons per minute during peak flows being
discharged to the Wightman Fork and that specific water quality data is necessary to
evaluate Alternative #4. EP A concurs with the concern about untreated, discharged water
in this alternative and wishes to. point out that Alternative #4 did not. ~tain as high an
. effectiveness rating as Alternatives #5 and #6 (see page 71)~ It is estimated that
.Alternative #4 approaches ARARs (IALs) water quality "requirements 90% of the time"
(see page 71, "Compliance with ARARs"). EP A has proposed Alternative #5 as the
preferred remedy. .
Comment 62: .
The Water Treatment FFS 'should discuss how Stream C flows are addressed by the
interim remedial actioDS and describe in de~..tbe planned "corrective measures" for the .
Chandler Adit. _:. ' . . .
,'.. .,.:.. .~... ...,~,. ""., ~-,. '..''''''''''''''.,.' . ""~'.~...:..'~~ "" ':'-:'-''''.'''' ""-...... . ",.t.
.. .
Re$,pOnse: .' . .
The Chandler Adit (Stream C) is CUIIeI1tly classified as an Emergency Response Removal .
Action (ERRA) con~t with action taken at the Reynolds Adit It is beyond the scope
of the Water Treatment FFSto address actions under ERRA. The focus of the Water
. Treatment FFS is Remedial Actions.
. - .
For specific information regarding the current status of the Reynolds Adit and the
p~ed corrective actions for the Chandler Adit refer to the Reynolds Adit Control
Program Report by ECC which was released at the Public Meeting on October 12, 1994.
Copies of this report can be obtained from the EP A Administrative Record, refer to .
Section 2.1 for locations. . .
"
, . .
However, the Water T~ent FFS does present the data from the Stream C over the last
98
. . -.
'r - -~.. -', - ~
- . . --
"" .......
""':':;.~.'_. ',::~.::"" .
.~~-- . ....-.'
. . .
. ,". '., .. ; ,-..." .
-"I::' ~:. ":--:- . ." ." .~.. '. .
. '..I.=:-. ..-.". ...
..- ..:.'::''''...k'~;'':':. ...
-------
.,....-.,-.-'-
,
.
,'.__0.
.. "'- -.- .. .-----.--.-.--"-'. -' ..-"
few years. Table 1, FFS, shows the significant improvement in overall loading
following the plugging of the Reynolds Adit, even with the subsequent release from the
ChaDdler portal. Irrespective of the improvement in overall water quality, EP A intends to
respond to the point source at the Chandler Adit with a corrective action to reduce or
eliminate the flow of water from the portal.
Comment 63:
Given the large runoff volumes at the Site as well as the significant disturbance of acid
generating rock, the RAO of red~cing or eliminating the continued expenditures for water
treatment at the Site may be infeasible and may lead to ineffective and misguided interim
remedial actions that are intended to reduce or eliminate water treatment costs. Also, these
interim remedial actions may exacerbate site problems, and, thus, be contradictory to the
NCP.
.
ReS1)onse:
EP A must evaluate alternatives that are protective of human health and the environment,
attain ARARs (or a waiver from ARARs), and are cost effective (see 40 CFR.300.430(f).
The protectiveness and ARARs criteria are considered thresholds that J:mm be met in
order to consider an alternative. The selection process is further defined using the five
balancing criteria and two modifying criteria. Cost effectiveness is one of the five'
balancing criteria in the selection process. . This factor follows in importance after the
protectiveness and the ARARs critericL Because EP A has identified the IALs as the water .
quality standards which must be met during this interim action period, it was determined
that the RAO "to reduce or eliminate the need for continued water treatment at the Site' is
an appropriate objective within the CERCLA process. Additionally, EP A directs the
commeniers to page 32 of the Water Treatment FFS where the full list ofRADs is
preseIited.Specifically~ the'W ater!te$nent 'Ff:8. 'i~enM~.1h.~ f~l1()~g~ opJec.~Yes prior
to the reduction of expenditures: .
.
to reduce or eliminate detrimental quality water flow into .the Wightman
Fork; .
to reduce or eliminate acid mine! rock drainage from man-made sourc~
on the Site;' . .
to reduce or eliminate any human health or adverse environmental' effects
. from mining operations at the Site, to include the Alamosa River...
.
.
The EP A feels that these objeCtives are quite clear and in compliance with CERCLA
mandates. .
Additionally, one commenter noted that current actions at the Site undertaken by EP A
may exacerbate problems and, thus, be contrary to the NCP. EPA believes' that each .
alternative was adequately evaluated for both short and 10ng-teIUl effectiveness and
99
. .
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~
. permai1ence and reduction 'of toxicity, mobility, or volume. Therefore, 'by implementing
the remedy as planned, EP A can be reasonably sw:e that problems will not be
exacerbated. However, if unforeseen events take place, EP A will take the appropriate
measures to ensure that the long-term effectiveness and perman~ce criteria and the
reduCtion of toxicity, mobility, or volume criteria are met. '
..
The Water Treatment FFS discusses short.;.term effectiveness in Section 5. Specifically, in
the preferred alternative evaluation, Alternative #5 (mOD Alt #4), states on page 75
under Section 5.6.5 Short- Term Effectiveness:
''There is an immediate benefit to containment and treatment 01 all point sources
01 AMD. Metals removed wl!uld not degrade waters downstream from the Site.
"Because 01 the remote location 01 the Site and existing access restriction, no
substantial risks to local communities or population is anticipated by
implementation of this alternative. '
"Primary risks to personnel worldng at the Site would be the same as those that
CUJ'Tently exist Measures implemented to minimize these risks are co~ained in
the Site Health and Safety Plan.
"Environmental impacts caused by construction of a solution collection and
routing system are considered minimal. Effects from construction 01 a
containment feature would not be significant.
'This alternative provides greater short-term effectiveness than any other
alternative, but approximately the same amount as Alternative #6. "
EP A believes that ~Jong~~> e1fectiy~~~ ptronanence and reduction, of toxicity,
, 'mobilitY or voiume' 'of the preferred' altemativeis similar to Alterative #6 'ana'~' ,
than Alternatives #1, #3, and #4. Further analysis within the Water Treatment FFS ,
provides the cost-effectivenesS element, pp. 75-76, indicating that the cost of Alternative
#5 is preferable ,to Alternative #6. EP A has fulfilled the Selection of Remedy criteria in
the NCP within the Water Treatment FFS and does not find the preferred alternative to be
contradictory to the NCP. '
Comment 64: ,
The reduction of toxicity, mobility, and volume through treatment criteria discussed for
Alternatives 3, 4, 5, and 6, (IROD Alts. 2,3,4 and 5) indicates that emuent WAD cyanide
and copper concentrations as low as 0.20 mgll and 0.05 mgll, respectively, can be achieved.
This information is difficult to assess, particularly since applicable cleanup standards have
not been provided. For example, this cyanide concentration would exceed the Final
.
100
, , ,
. . ": ... . - :.. ~. ~,
. . ..- -..' .." .'
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-.---- ...----.
,
Numeric Criteria Level for cyanide (0.05 mgll) listed on page 22, while meeting some of the
Potential Interim Action Levels listed on page 23.
. .
..
Res:ponse: .
- One commenter was concerned that the treatment systems identified in Alternatives #3,
#4, #5 and #6 (IROD Alts. #2, #3, #4, and #5) will not be able to reduce-toxicity,
mobility, or volume to AR.ARs levels. EPA believes that by meeting the IALs the Site
will be able to comply with the Segment 3b standards which are ARARs for the Site. The
treatment technologies in the Water Treatment FFS alternatives identified by the .
. commenter will be utiliz-ed to treat the ANID and cyanide so that the Site ~ges meet
the IALs at WF-S.5. .
Comment 65:
The Water Treatment FFS states that the effects of interim remedial measures are
unknown. However, Section 3.8 states that alternatives developed ~ the interim remedial
action (Le. relocation of materials in CWP, BMD and CC, and plugging of the adits) are
significant methods to reduce contaminated water volumes. These statements are
inconsistent. .
Res.ponse: .
One commenter found the Water Treatment FFS inconsistent because it states that the
effects of the remedy.are unknown yet continues to assert that the actions taken at the
CWP, BMD/SDI and underground workings are significant methods to reduce
cont~m;n~ted water flows. The Water Treatment FFS evaluated the effects of different
water treatment options on Site conditions. The impacts associated with the CWP,
BMD/SDI and ~tactions are eValuated,in ~arate reports..EPA believes that the long-
term effects of water treatment at the Site are uDknown... Currently.,..Momson.Knudsen - .,... ,n'
Engineers and the U.S. Geologi~ Survey are conducting studies to more adequately
characterize these long-term unpacts. EP A believes that the short-term effects are known
(i.e., compliance with IALs) and is confident that the short-term source control affects
from interim action water treatment activities will mitigate the impacts of the potential
short term poor water quality resulting from other activities at the Site. This. includes
fl1Jsh;ng of dirty rinsate from the CWP and BMD/SDI "footprints" which remain after
excavation and removal actions. . . ..
...
Comment 66:
The Water Treatment FFS should be more specific regarding the rationale for replacing
alkaline chlorination with hydrogen peroxide oxidation. The relative cost impact of using
hydrogen peroxide oxidation in lieu of alkaline chlorination should have been evaluated.
In addition, ;alk!lline chlorination may be suitable for in-situ destruction of cyanide in the
HLP. Therefore, it should have been considered as an alternative in the screening process. .
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~.
Response:
The use of alkaline chlorination has significant impact on the use of treated waters in the
Heap Leach Pad. This is briefly mentioned in the Water Treatment FFS but more fully ,
addressed in the Heap Leach Pad FFS. The Water Treatment FFS addressed the
continuation of CDP only inasmuch as required by the HLP effort identified in the Heap
. Leach Pad FFS. Costs of the Water Treatment FFS allowed for continuation of the .
existing processes for two years to assist in this task. p.l1caline chlorination was
considered for AMD treatment after the two year HLP detox period but was mled out as a
treatment option in the Water Treatment FFS. EPA would like to point out that alkaline.
chlorination technology was applied by former operators at the Site with minima) success
. and numerous problems, particularly with scaling, sludge management and reagent
material.handling. Substantial data is available in the admini~tive record for the
commenter to review in support of this decision.
..
Additional comments were received regarding the Water Treatment FFS. technology
evaluations, particularly.the screening of hydrogen peroxide, sulfur dioxide, sodium
hydroxide, quick lime, hydrated lime, and sodium carbonate technologies. In general,
EP A used sev~ different databases to develop these analyses. Morrison-Knudsen
Engineers provided a comprehensive evaluation of waste water technology applications at
the Site for the RI/FS-please reference the Task #14 report. Additionally, Weston
provided a waste water process evaluation in 1993 (REAC Team, February 1993).
'Substantial input on available technology development was taken from the responses
which were received from the Environmental Chemical RFP in 1993 .and 1994. EPA
would like to refer these commenters to these Site-specific technQlogy databases for
technical review. .
Individual comments were received about the desirability of heavy flocculation
parameters and specific conmmimmMreatment-processes:-:EPA'did evaluate.the ,'p. .' ,
eff~veness, implementability and cost of a technQlogy which inc,luded niateriai .....", ~. ,
handling considerations. Preference was'given to those technologies that had lower' .
overall material handling burdens, specifically, lower amounts of sludge generation and,
therefore"lower amounts of treatment residual impacts. EP A is directed to evaluate this
parameter in 40 CFR 300.430(e)(9)(D)(S) which identifies the evaluation criteria as:
'The type and quantity of residuals that will remain following treaiment,',:. ,
considering the persistence, toxicity, mobility, aiul propensity to bioaccumuIate o[
such hazardous substances and their constituents;"' .
.
Technologies which resulted in larger amounts of sludge generation (i.e., heavy
flocculant loading) were graded less favorably than processes that generate less sludge.
This analysis parameter was included in the Focused Water Treatment Remediation goals
found on pages 32-33 of the Water Treatment FFS, "!vfinimi'7ation of treatment waste
102
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. .
products and waste disposal requirements; and, Realization of practical resomce recovery
. to the degree that lowers overall treatment and Site remediation costs. n These analyses for
the different technology types listed can be found in Section 3 of the Water Treatment
FFS , pages 40-57. , . .. --"-"" - - .."
Also, EP A believes that the attainable treatment parameters identified in the preferred
alternative for suspended solids, arsenic, ferrous iron, mercury and silver were considered
sufficient at the cmrent design level to meet ARARs during the interim remedial action
period. EP A prefers to obtain a desired cost estimate within an order of magmtude
accuracy, stated as +50% to -30% (see OSWER D~ve 9355.3-01, Section '6.2.1, pg.6-
4). EP A believes this level is achieved with the preferred alternative aJld the identified
COCs from the commenter. .
Comment 67:
The cost estimate for Alternative #6 (IROD Alt. #5) does not include a reduction in flows to
be treated as was assumed for Alternative #5 (IROD Alt. #4). Yet, no explanation or
justification ac.compames this decision. Why not? .
Re$,pOnse:
The cost estimate for Alternative #6 (!ROD Alt. #5) does consider a reduction in
treatment from 1996 through. 1999. . This reduction in costs is related to 'areduced
treatinent volume. However, it is assumed that as treatment volumes go down, the plant
will operate at lower flow rates or, below capacity, for most of the year. When a .
treatment plant is not operating at capacity, the treatment cost per gallon increases. As a
resUlt, there are no further redu~ons in cost. This is an accepted cost esrimarine practice
in the industry where cost efficiency of a plant is related to the percentage of the plant
capacitythatisutilize
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"
due to the lack of space resulting from source control actionS at the Site. EP A has
- identified anoxic limestone drains as a "passive pretreatment technology" (Water
Treatment FFS, pg.54). As such, this technology would not be effective at the Site as a
, , '
primary treatment technoJogy even with sufficient space to implement this technology. "
EP A would like to note that the use of anoxic limestone drains was eHminmed from
interim consideration during the five year implementation period for this remedy. This
technology is still viable to address the pretreatment water flows into the constructed
wetlands for the Final Sitewide remedy. The Water Treatment FFS states this in the same
effectiveness analysis, "Anoxic limestone drains are generally used to treat AMD before
routing to constructed wetlands". EP A believes that the Water T~ent FFS aDaljrses
. provides the proper perspective on an overall, integrated Site remedy; that is, ,
develoPment oflong-temi protective passive measures through the interini source control'
measures. These interim ~edial actions found in the Proposed Plans will be
, implemented to support the eventual cess~tion of Water treatment expenditures at the Site.
.
Comment 69:
Current sludge disposal practices should be addressed in the Water Treatment FFS since
on-site sludge disposal is currently being practi&:ed. Without such information, more
meaningful comments cannot be provided. "
Ft~nse: ,
'One commenter was concerned over current sludge disposal practices on the Site while
noting that EP A included a discussion of sludge disposal impacts within the Water
, Treatment FFS. EP A has included a supporting document in the Administrative Ftecord
which encompasses the Site sludge management plan. This document is available through
the EP A R.egion vm Superfund Ftecords Center o~ by contacting Ms. Laura Wi11iam~,
(303) 293-1531.
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2.3
Summary and Response to Genel-a1 Comments
. Introduction On August 16, 1994, the United States Environmental ProteCtion Agency, Region
vm (EP A), issued four Focused Feasibility Studies (FFS) relating to proposed remedial action
work at the Summitville Mining Site. These four FFSs relate to: (1) Cropsy Waste Pile,
Summitville Dam Impoundment, Beaver Mud Dump and Mine Pits; (2) Heap Leach Pad; (3)
Water Treatment; and, (4) Site Reclamation. EPA requested public comment on the four FFSs
and extended the deadline for comment to October 24~ 1994. . .
Comment 1: '. '. -. .. ,. .
, A number of commenters complained that some of the alternatives evaluated by EP A in
these FFSs are already being implemented without EP A having followed the remedy
selection and public participation procedures of the NCP.
In particular, various commenters objected to the continued placement of the Cropsy
Waste Pile into the Mine Pits pursuant to an emergency-like schedule, despite public
comment on EP A's previously issued Engineering Evaluation/Cost Analysis (EElCA). This
prior public comment stated such action was inappropriate because EP A did not consider
the feasibility of capping the Cropsy Waste Pile in its original location and EP A failed to
consider potential short and long term impacts on acid mine drainage. Commenters
believe removal of the Cropsy Waste Pile and its 'placement in the Mine Pitts will exacerbate
site conditions. ..'
In spite of these public comments, EP A awarded a contract in July 1994 to complete the
excavation and relocation of the Cropsy Waste Pile (CWP), Beaver Mud Dump (BMD) and
Summitville Dam Impoundment (SDI) into the Mine Pits accordfug to the EEICA. and ,
Action MemorandulIL Commenten now object to EP A selecting the placement of the
Cropsy Waste Pile, BMD' and SDr into the MmeP-itS as.a r.emediaI.action.alternative. .. ,-" ....., ,
Commenters have suggested that by selecting the EEICA response action as the interim '
remedial action, EP A has "pre-selected" the remedial action for the Cropsy Waste Pile and
has circumvented the public participation procedures mandated by the Comprehensive
Environmental Response, Compensation' and Liability Act of 1980, as amended (CERCLA)
and the National Contingency Plan (NCP). .
~
, '
Commenters note that both CERCLA and the NCP establish specific steps and procedures
that EP A must follow in selection a remedy for all or a portion of a CERCLA Site. &.ca
generally, 42 U.S.C. 9604, 9621; 40 C.F.R. 300.430 and claim that EPA has not followed '
the NCP procedures. The commenter states that EP A justifies the implementation of the
allegedly "pre-selected" remedy by arguing that the public participation undertaken
during the EEICA process last summer satisfies the public's right to participate in the
remedial selection process for the Target Areas.
-------
,
Re~onse:
Excavation and consolidation activities associated with Cropsy Waste Pile, Beaver Mud
Dump, Suminitville Dam Impoundment (formerly called the Cleveland Cliffs Tailings
Pond), and Mine Pit were initiated under an EP A non-time critical removal action. " .
"pursuant to Section 300.415 of the National Contingency Plan. Such rem~val" activities
are appropriate when, among other things, "excavation, consolidation, or removal of
highly contaminated soils ftom drainage or other areas... will reduce the spread of, or
direct contact with, the contamination." (See Section 300.415(d)(6) of the NCP at 55
Fed Reg. 8843 (March 8,1990).) Once EPA determines such removal actions are
appropriate, response actions shall begin as soon as possible to abate, prevent, minimi7.e,
or eliminate the threat posed by the contamination to public health, welfare of the
environment (See S~ction 300.415(b)(3) of the NCP at 55 Fed Reg. 8843 (March 8, .
1990).) .
According to the NCP, if a six-month planning period exists before EP A initiates a
removal action, EP A must conduct an Engineering Evaluation/Cost Analysis (EElCA).
This analysis, although not as extensive as a Remedial Investigation! Feasibility Study,
identifies the objectives of the removal action and analyzes the various alternatives that
may be used to meet these objectives, based on the alternative's cost, implementability
and effectiveness. " The EEICA is then released for public comment, according to the
public participation procedures established in Section 300.415(m)(4). Finally, after a
minimum 30-day public comment period, EP A issues an Acti~n Memorandum which
documents EP A's selection of an appropnate non-time critical removal response action.
. See also. "Guidance on Conducting Non-Time Critical Removal Actions Under "
CERCLA," EP Al540-R-93-05?, Publication 9360.0-32 (August 1993).
EP A meticulously followed the NCP~pIescribed procedme in "proposing and Seiecting the
EElCA-based non-time critical remQval for the Cropsy Waste Pile, Beaver Mud Dump,
Summitville Damlmpoundment (formerlrcai1ed the~elev~1and€tiffs~~g$Pond).,-, ..
and Mine Pit (collectively, the Target Area). EP A published its EEICA in July of 1993,
solicite~ and accepted public comments on the EElCA uutil early September of 1993,
responded to those comments in its "Responsiveness Summary to the Engineering
Evaluation/Cost Analysis for the Cropsy Waste Pile, Beav~ Mud Dump, the Cleveland
Cliffs Tailings POQ.d (now called the Summitville Dam Impoundment), and Mine Pits,
. Summitville Minesite, Rio Grande County, Colorado," and issued its Action
Memorandum on September 24, 1993. EPA let a contract to begin implementation of
this part of the EEICA-based removal" action in July 1994.
EP A is not arguing that providing the public the opportunity to comment on the EElCA is
sufficient to substitute for soliciting public comment on tbe Target Area FFS and
Proposed Plan. EP A agrees that the NCP does not allow EP A to satisfy its public
participation obligations for a proposed plan by reference to another document. EP A also
agrees that the analysis EP A conducts to evaluate removal alternatives differs greatly
,
106
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from the analysis conducted to evaluate remedial alternatives. For non-time critical
removals, EP A evaluates the alternatives in terms of effectiveness, implementability and .
cost alone. The evaluation of remedial alternative is conducted using the nine criteria of
Section 300.430 of the NCP. The two sets of evaluation criteria are not synonymous. .
. EP A, however, did fully comply with the NCP-prescribed procedures for screening,
proposing and selecting remedial alternatives for the Target Areas in its Focused.
Feasibility Study, Proposed Plan and Interim Record of Decision (IROD). The removal
alternative previously selected in the Action Memorandum was one of the alternatives
. evaluated during EP A's remedy selection process. EP A took public comment on the
relative merits of all alternatives evaluated in the FFS vis-a-vis the nine NCP criteria and
proposed its preferred alternative in a Proposed Plan, issued in accordance with Section
117 of CERCLA. The alternative previously selected in the Action Memorandum, as
expanded in the FFS and Proposed Plan, met the threshold remedy selection criteria of
the NCP and provided the best balance of the NCP's "balancing" and "modifying"
criteria. It was selected as the appropriate remedial action in the Interim ROD for the
CWP. In accordance of the remedy selection criteria of Section 300.430(e) and (f) of the
NCP. .
EPA therefore selected both the 'EE/CA-based removal action and interim remedial action
according to the different, applicable standards and procedures of the NCP. The fact that
the two response actions are similar does not make the implementation of the previously
selected removal action illegal or invalid. Moreover, with the letting of the July 1994
contract, EP A was merely initiating the implementation of its validly selected removal
action. EPA's publication of the Target Areas FFS and Proposed Plan bas no bearing on
and should not interfere with EP A going forward with this removal action.' '
- '."..., '.
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Comment 2: ,
One commenter strongly recommends that EPA delay removal of the Cropsy Waste Pile
until all the' potential ramifications have been properly evaluated by the public and by
competent technical consultants~ Such an evaluation should be conducted after EP A's
"Use Attainability Study," which will characterize and evaluate dOWDstream..effects from
the Site, is completed. ~e commenter' believes there is no reason to impleme~t this remedy
on an expedited schedule.' ",u, ,-,' , ", - , .
~
R~nse: .:
The Use Attainability Study is being completed by the State of Colorado, Division of
Minerals and Geology. The findings of this $tudy will be incorporated into EPA's final
response action for the Site. In the meantime, EP A believes the environmental benefits
that will be gained from the implementation of interim remedial actions at the Site far'
outweigh the continued releases of mine waste. ' ,
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fl.
Comment 3: .' . .
Commenters requested an exPlanation oCEP A's rationale Cor issuing interim rather than
final RODs. These commenters Ceel EP A has no legal or technical basis Cor issuing IRODs
. ~d that there will be additional costs associated with first implementing an interim
remedy prior to making a final remedy selection. They also expressed the belieC that some
oC the interim remedial actions may actually exacerbate site conditions and contamination
or may prove ultimately incompatible with final remedial action(s) for the Site.
Re~nse: .
According to EP A guidance, interim remedial actions are appropriate to "take quick
action to protect hUman health and the environment from an imminent threat in the short
. term, while a final remedial solution is being developed." ~ "Guide to Developing
Superfund No Action, Interim Action and Contirigency Remedy RODs," .US EP A,
OSWER Publication 9355.3-02FS-3 (April 1991), at p. 5. .
Deterioration of site conditions will lead to continued and heightened exposme of
sensitive human and ecological populations to heavy metals and chemicals ~ cyanide)
used by Galactic and others in their mining operations. The IRODs institute temporary
measures to ~ilize the Site and prevent further migration of contam;nants of concem
from the Site into surro11nding soil, air and water media. Further, the types of interim
. : actions selected in the IRODs, such as the relocation of contamination from one portion
of the Site (CWP) to another (Mine Pits) and the installation of caps to prevent further
migration of contaminants are exactly the types of response EP A guidance states are
appropriate to implement as interim remedial actions. See. "Interim Final Guidance on
. Preparing Superfund Decision Documents," OSWER Directive 9355.3-02 (June 1989), at
Chapter 9. .
Given the existing Site conditions, EP A is certain that ti11.iD.g the Mine Pits will
significantly reduce the-ftow-inte .the .Pits"and~prevem diseharges-of acid. froIp;the ¥iDe
Pits into underground workings and ground water. .Relocating other mine waste features
such as the CropSy waste Pile; Beaver M1,1d Dump and Summitvilie Dain Impoundment
to the Mine Pit will also mitigate these areas as. sources of acid mine drainage. Capping
the Mine Pits will serve to eHm;natp. or significantly reduce the movement of .
conmminants of concern through water and air pathways. Treatment of smface water and
detoxifying the Heap Leach Pad will eHminate releases of metals and cyanide. . Overall,
. the implementation of interim response actions will quicldy reduce the im~inent threats
to human and environment receptors at and around the Summitville Minesite. EP A will
also continue to monitor the progress of these remedies in eliminating or reducing the
release of hazardous substances from the Site and will determine what, if any, final
remedial actions are necessary to address the remaining risks at the Site. .
.
108
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Comment 4:
~y commenters sought clarification which applicable or relevant and! appropriate
requirements (ARARs) of federal and state statutes and regulations must be complied with
for remedial actions at the Site. Commenters wanted an identification of which ARARs
will be met with by the interim actions and which ARARs will be waived. One commenter
cautions against the use of "Technical Practicability Waivers" as shortcuts.in the
remediation.
ReS1'onse:
The ARARs clarification is provided in the specific Responsiveness Summary on
ARARs. Each IROD also identifies the relevant portions of federal and state
requirements are being complied with or waived in the implementation of the interim
remedial actions. Commenter should be assured that all ARARs waived with the
selection of interim remedial action will be re-evaluated for the final remedial action( s)
for the Site.
Comment 5:
One commenter noted that each of the FFSs states an "observational site approach" will be
taken as part of EPA's interim remediaI actions. This commenter believes that an .
observational approach may be an effective approach to site remediation, provided that all
the possible outcomes of the proposed action are identified, evaluated and mo.nitored. The
commenter suggested that for potential outcomes that may have adverse consequences, the
impacts ass.ociated With those outcomes and the probability of their occurrence must be
qualitatively defined. If adverse consequences are likely, or that site conditions could be
make more complicated and problematic, then implementation of the proposed remedy
must be reconsidered. Finally, the commenter declared imple~entation of a remedial .
action without an oveniII pliiilfor eaclideaIiiigmtli..range.ofthe poteiltiall.outcomes is....
inconsistent with a responsible observational approach at a complex site like the
. Summitrille Mine Site. .
.
ReS1'onse: .
As discussed in the "Analysis of Alternatives" section in each of the m.ODs, EP A has
considered all the relative merits and detriments of the potential remedial actions
evaluated. "Potential adverse consequences" of implementing the alternatives was
evaluated, as was EP A's ability to deal with these potential adverse im,pacts when EP A
reviewed the overall protection. to human health and the environment, long-term
effectiveness and permanence, Short-term effectiveness, implemei1tability criteria of the
NCP. The interim response actions selected in the IRODs represent the alternatives that
provide the best balance of meeting these criteria. EP A will employ the "observational
approach" to continue to evaluate these interim remedial actions' effectiveness in meeting
these NCP criteria, EP A's remedial action objectives and performance standards and to
determine what, if any, additional final remedial actions are necessary to ensure that
..
109
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. "
human health and the environment are protected against unacceptable risks posed by
hazardous substances remaining at the Site.
. . . . .
Comment 6:
A number of commenters are concerned about EP A's estimate of costs to ~e expended at
the Summitville Site are too low. Commenters have calculated those costs (both removal
and remedial) as exceeding EP A's 5120 million estimate. They are concerned that the
staggering amounts for interim response do not include the cost of the final remedy or
remedial investigation/feasibility studies presently being conducted at the Site.
.
..
. Re$;POnse:
. The commenters are correct in their observation that EP A's initial cost estimate bas been
exceeded with the collective costs of the interim re~edial actions selected in the !RODs.
The altematives selected in the IRODs were screened for cost, and EP A believes that they
are cost-effective. As studies at the Site provide additional information and as remedial
actions are implemented, costs for remediation of the Site will continue to be reassessed.
Comment 7: .-
Commenters object to the backfilling of the Mine Pits and the plugging of the Reynolds
Adit, since in their view, these actions preclude a future beneficial use, that of re-mining.
. '. The commenters believe that EP A's remediation activities should be immediately
terminated or suspended until the impact to future mining uses can be. thoroughly
evaluated.
Re$pOnse: .
None of the proposed or completedEPA activities preclude further mining activitieS at
the Site. However~,'any'>future mining aetiviti~-must-'be-~.wjth.~d not:i~~enr ~.
with the ~nse actions EP A has implemented at the Site. EP A's remedial actions are
intended to prevent the exposure ofhnman~ and ecological populations to hazardous .
sub$taDces. Any future mining activities that do not exposure these populations to
hazardous substanCes may be acceptable to EP A. It is anticip. however, that EP A
will have to review any future mining plans to ensure the protection of human health and
the environment .
Comment 8: . .
Commenten object to EP A's lack of a comprehensive Record of Decision for the Site and
the implementation of parallel or isolated and disjointed actioDS at the Site without any .
overall plan or remedial strategy for the Site. To remedy this lack of coordination, the
commenters su~~t that an independent board of technical experts review and select Site
response actions.
.
110
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~~onse: .
EP A believes that the interim remedial actions selected in the IRODs provide a
comprehensive, coordinated approach to addressing the risks at the Site. Specifically,
EF A believes that all the remedial measures to be implemented according to the !RODs
will go a long way in improving sitewide water quality by controlling surface nm-on and
run-off, erosion, leaching and metals and other cont~minant loadings to the Alamosa
. River. .
.
Empowering an independent board of technical experts to review and select remedial
actions at the Site is improper under the Superfund law. Congress explicitly charged
EP A with the authority to select response actions to cleanup releases of hazardous
substances under the CERCLA Section 121 ofCERCLA. In fact, this section of
CERCLA unequivocally states that "the President shall select appropriate remedial
actions determined to be necessary to be carried out under section 104 or secured under.
section 106 which are in accordance with this section, and to the extent practicable, the
national contingency plan... " [emphasis added]. The President has delegated that
. authority to select response actions at Superfund sites to the Administrator of EP A. The
procedures the Administrator must follow in selecting these cleanup actions are contained
the National Contingency Plan.1 The NCP provides that affected and interested parties,
such as States, PRP and citizeris are given the opportunity to participate in the selection
process, but it is clear that the Administrator retains the responsibility to select the
appropriate remedy.
- .. . ".. .
Thus? While EP A welcomes input from the community and neutral third parties
concerning the actual health risks from lead-contaminated mining wastes, EP A cannot
abrogate statutory responsibility to be the decision maker in selecting remedial actions for
.Superfund sites. EP A can also nOt allow:a.thiId.partr .to.d~~~~. .~~ ~~pri~..~~pe .
ofEP A's remediation plan, since it is our experience in identifying health and .
envirOnmental risks and designing the remedies to address them that Congress relied
upon when it empowered us with the authority to select and implement remedial actions
under Superfund. . .
.
..
1. See. e.~. Section 120(e)(4) ofCERCLA (where if the head of the relevant federal agency
and the Administrator ofEP A cannot reach an agreement of the remedial action to be selected,
. . the Administrator selects the. remedy).
U1
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Comment 9:
One commenter noted that downstream impacts are currently being ipored and avoided
despite the above stated Remedial Action Objectives. Avoidance of downstream impacts
adversely affects Terrace'Reservoir, hoUsehold and municipal wells and allows agricultural
' land to further degrade. ' ,
.
Re~onse= ,
Due to the Chandler Adit drainage, all downstream targets are be'ing addressed as quickly
as possible. All three 8reas mentioned above are part of major research efforts included
in the justification of remedial actions at the Site. Terrace Reservoir is CUIIently
undergoing a study conducted by the U.S. Geological Survey. Agricultural lands have
undergone several studies, 'including those conducted by Colorado 'State University. With
regard to household 'water use, local water supplies have been sampled twice and are
undergoing long-term water sampling. '
..
Comment 10:
The same commenter stated a site drainage plan, which provides control for
surface/s~bsurface drainage, storm water and sedimentation management.and non-point
source collection! treatment, is needed. ' ,
Re$pOnse: ,
A site drainage plan has been implemented. A copy of the plan is available in the
Administrative Record.
Comment 11: ,
One comnienter identified a need for a waste management plan.
, ' ,Re~onse:"'" ,', ",' ,,'... '," . - <,,'" -," '" '" " ".. ,
A number of the !RODs have elements is designed to meet waste mflnagement ARARs.
The Sainpling and Analysis Plans describe how investigative derived wastes are
managed. Also, used oil is being nqcled and, as stated in the Focused Feasibility Study,
sludge produced on-site is being recycled for metals recovery. '
Comment 12: , ,
One commenter is concerned that EP A does not have sufficient date to establish the
Summitville Dam-Impoundment (SDI) as a source of sulfide-rich tailings and metals-laden
acidic water discharged to WIghtman Fork. The lack of this data calls into question the
need to remediate the SDI at all, or at least the nature and extent of such remediation. The
commenter suggests EP A collect additional data regarding the nature and extent of
contamination at the Beaver Mud Dump (BMD) and SDI before proceeding with - -,.
remediation of these areas.
.
...
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. ReS1)onse: .
Historically, the Summitville Dam Impoundment and the Beaver Mud Dump area have
. been of significant concern to regulators ftom the State. Water discharges em~n~ting
from these materials has been recorded as being of poor quality. Based on existing data,
historical precedent, and current sampling and analysis information, EP A determined that
the SDl and BMD are significant contributors of man-made AMD at the Site. Data
collected by Anaconda prior to SCMCl operations states that the mill tailings disposed of
in this area are strong AMI) generators. Movement of these sources and the Cropsy
Waste Pile to the Mine Pits allows capping of four AMD sourc~ in one action.
.
. .
Comment 13: .
. One commenter argues that the FFSs and Proposed Plans fails to comply with the NCP
because: (1) these.documents evaluate the "No Action" alternative for the Site as a whole,
rather than by the subject matter of each interim remedial action, (2) they fail to consider
naturally-occurring background concentrations of metals and acids in EPA's analysis of
. alternatives, and (3) compliance with ARARs and/or ARAR waivers have not, been'
identifie~ with any amount of specificity. . .
Re5J'onse: .
Alternative No.1 for each of the Focused Feasibility Studies is' a No-Action Alternative
related' to. that particular portion or media c:>f the Site. .
. .NaturaIly-occurring background levels ofmeta1s and acids were taken into account when
evaluating ARA.Rs for the interim remedial actions. For example, EP A deterInined it was
, approPriate tp waive the Segment 3b stream classification as an applicaple requirement
"" - tha.t must be 'met by the1RODs becaUse of.the:hiStoricJ:ontrihUtionS Dfmetals. and acids. ... ,.
from naturaIly-occurring sources. EP A will determine if this ARAR should be waived in
~y final ROD(s) for the Site when additional background and load reduction infonnation
is collected. .
.
Comment 14: . .
Cleveland-Cliffs Iron Co. and Union Pacific Resources ComIJany. Submitted information
regarding their (or their predecessor-in-interest's) operations at the Site, their analysis of
the current state of.CERCLA case law related t9 liability and legal arguments evaluating.
their lability at the Site. . These commenten also requested that EP A refer to the area
adjacent to the Beaver Mud Dump, which EP A has referred to as the Cleveland-Cliffs
Tailings Pond, as the Summitville Dam Impoundment or some similar appellation. .
..
Re5J'onse:
While EPA appreciates infonDation regarding parties' prior activities at.the Site,
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~
particularly if this information supplements EP A's CERCLA 104{ e) information requests
or helps EP A to characteriZe the .wastes at the Site, EP A believes a submission that
. purports to provide comments on an FFS and Proposed Plan is an inappropriate foIUIn to .
state one's view of its liability at the Site. Such comments are more appropriately
submitted as part of a party's response to EPA's CERCLA Section l04(e) request, EPA's
Notice Letter or in confidential settlement correspond~ce between EP ~ and the
submitting party. A specific response to Cleveland-C1iff7UPRC's legal arguments will be
forwarded under separate cover.
.
.
Without any qualitative jUdgment on the merits of Cleveland-C1ifi7UpRC's lc:gal
arguments, EP A nonetheless agrees to hereafter refer to the area below the Beaver Mud .
Dump as the Summitville Dam Impoundment Conesponding changes to this
nomenclature will be made in all :futureEP A documents.
RESPONSIVENESS SUMMARY: GENERAL WJUIIEN CO~cEIVED FROM
CmZENS AT LARGE OF 1.:.HE..SAH.Lms VALLEY
These written comments represent the universe of comments received through the end 'of the public
. comment period.
Com~nt 15:. '.
To whom it InaY concern: My name is Roger Gallegos I have lived in the San Luis Valley just .
. about all my life. Before the Summitville Mine came to exist, life was good. After they
. exploited the government and us, life became. much more difficult. Take for instance, when
we woUld water our fields, we could catch fish in our ditches. Another thing I have noticed is
the crop yield. 'Before the mine came in my meadow would yield 3000 to 3200 bales o(hay.
When the mine had there spills -I -yielded.f642 bales~'My ~esry~hile 'tile .w~~er .q1;l~~
improved was about 2853 bales. Now this may not sound important, but it is. I used to sell
hay for a Jiving, and now I feed it to my cows. The mine has hurt my family in the pocketbook.
. We have'all been hurt'by the mine in this community. The government should never have let
. them start to begin with. Galactic Mining should be made responsible for. the clean up. then
the Government for allowing them to do this. Since the mining company has gotten away with
'this, we should not be made to suffer for other peoples mistakes. I say Summitville should be
cleaned up and restored, and our water be put back to normal My Great Grandfather made
a Iivmg with my ranch, as did my Grandfather and Dad. I want my kids and their kids to
continue making a living on what is theirs. They have that right, and not be forced to suffer
for what someone else was allowed to do. I myself believe the plan to filter the water down
below where the creeks meet, is the best idea. That system for 8 million, could save money and
work. Thank you for listening. The GaIiegos Family. (Letter; undated; no. other data given]
.
4
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Comment 16: . . ... . .'
Dear Ms. Williams: As a farmland oWner With land .irrigated from the Al8mosa River I am
deeply concern.ed and worried what' the continued use of the contaminated water wili
eventually do, not only to the land, drinking water from the wells, but also to the livestock and
products which are ultimately consumed by the general public. There are those who say it has
no ill effects on crops or livestock - but for how long. I do know it has played havoc with the
steel structures in the irrigation system. I'm under the Capulin Ditch and we have had to
spend over $40,000.00 replacing aD steel structures. I may say that I was Water Commissioner
for this district and know the Alamosa River quite welL In this time I never saw when so many
irrigation structures aD deteriorated ~ such short time. As for those who say there never were
any fish in the Alamosa River - it is not true. Why else would the Game and Fish. Department. .
consider it a fishing stream. People.would ice fish all winter in the Terrace Reservoir up to the
time the mine started to dump the mess into the stream. I have lived here all my life and can
remember when we were little Dad would take us fishing there. As for the different options
to solve the problem it seems to me one that would treat aU the water before it got into the
Alamosa River would be the one - probably in just one pond. Thank you Sincerely, Leo B.
Gonzales [Letter; dated Oct. 19, 1994; address and phone number given]
. .
. . "'..
.. . '.-- .
Comment 17: .
Dear Ms. .Williams & EP A Summitvi1Ie Team: Although I may be Writing too late for the case
record, perhaps your comment period's been extended; in any case, the information leading
me' to voice iny concerns reached me after the original deadline. Y our. recommended plans
generally seem to stress reliance on systems that won't need t~o much up-keep once set in .
place. The biotreatment aspect sounds favorable. However, it has come to my attention that
"caps" or "plugs" contributed to poorer water q~~ty late.in.this YeaJl"S irrigation season,
. since. the' caps rechanneled containinated -wat~r-intO'-other-drainage-chtDDeb..that"weren't .
. serviced by your water treatment facilities. This indicates two planning facton to me: 1. you'll
want to assess where water will eventually seep out before you stai1filling the mine pits with
waste materials that are likely to displace ground water,. and 2. it woD;ld make most sense to
. locate your water treatment unit(s) as far downgradient as possible, even if this entails
. relocati~n of the existing facilities. I was also surprised that the recbUnatioD pian ~mentioDS
no reseeding or tree transplanting details. Although it mayor may not meaD anything
. scientifica1ly, I notice tha~ ~e Alamosa creekbed'srocks have a much leSs "rusty" surface
coloration near my house than they ever did during SMC's ~t four years. Thanks for your
efforts. Sincerely, Paul Sinder [Letter; dated 9/27/94; address given] .
.
.
Comment 18:
To Laura Williams: I am writing to voice my concern on the clean-up efforts being taken at
the Summitville mine site. . Mainly, I would like to state that I fully support the alternatives
researched and proposed to you by the T .A.G. committee. I hope the E.P.A. sYstem is tlexible
115
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and the T .A.G. proposals not only be reviewed, but also implemented. I thought the public
meeting on October 12th, was very informative and positive. It I~ me to believe that, although
you have plans made and on paper, you are open to suggestions, criticism and change. 'The
, T .A.G. proposal on water treatment is to my opinion a priority. ,It will make an immediate
difference in the water quality coming downstream and into our valley. I do hope this will be
rea1ized as soon as possible, it seems common sense. Looking at the T .A.G. proposals, I think
they have found several solutions which promise more lasting and better results (and in some
cases a smaller price tag). A question I have too, is whether the E.C.C has the experience to
tackle the job up there. How many other experts and companies have been approached for
their expertise and advice? I am optimistic that you wiD find a way of working together with
the T.A.G. team in finding the right solutions. I appreciate the work you are doing and am
keeping my fingers crossed ~t all goes well I realize it's a tough and very complicated job.
Sincerely Lisa ter Kuile A rural resident surrounded by Terrace irrigated land. (Letter;
undated; no other data given]
.
Comment 19:
Dear Ms. Williams: We want to support the recommendations made by the TAG' for the
Summi~e Mine Site. We are concerned here in Conejos County about water quality and
the long term effects oftheSummitville Mine Site. We want the agricultural community in our
county to remain stable so our role as County Commissioners must look toward the future and
address the long term consequences connected with this site." Please take the TAG
recommendations seriously, the quality of our land aDd water will determine the future of our
communitY. Sincerely, Le Roy Velasquez, Chairman Conejos County Commissioners
(Letter; dated October 18,1994; typed on Conejos County'Government letterhead]
Comment 20:
Dear Ms. Williams: ,We, aBoard of-Directon-.of.th&¥eUe-,del&I-.(2ommunity Center iD
. . .' .' .' ... -. ..'., . '7"" . ~.. .'
Capulin, 'are extremely concerned about the SuinmitviDe Mine Site and its continuation clean-
up efforts. We' are very interested in the quality of our water for our homes as' wen as for our
farms. We support the enclosure made by the Technical Assistance Grant Committee. We
have showed our interest by lIJalring our community center available for meetings so that the
community wiD continue to be informed and to participate in the prqcess. If there is anything'
else we can be doing, please let us know. ' We are fully aware that the results of the SummitviDe
Mine Site on the quaIityof our water will determine our livelihood in Capulin; Sincerely,
Vane del Sol Community Center Board of Directors. (Letter; dated-October 18,1994; five
signatures, spelling approximate: Rev. Randy Brennig, Delma, Ramirez, james A. Quintana,
Cindy Medina, Julia Gomez-Nuanes; typed on Valle del Sol Community Center letterhead]
..
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.
Comment21: .
. Dear Ms. Williams, After reading the TAG newsletter and, listening to Maya ter Kuile, I have
. some misgivings about the E.P.A. plans for Summitville. The TAG suggestions surely seem
much more reasonable and straight forward than the EP A's approach. Their cost effectiveness .
seems much more desirable also. As a new resident to the area I.urge you to look again at
what has occurred to the Alamosa River; consider all of us who drink and irrigate in this area
and rethink your approach. to what you (Le. EP A) are doing at Summitville. Thank you
[Letter; dated 21 Oct 94; unreadable signature; address given] ..
.
. Comment22: -,' "'.. " .
Dear Ms. William'~, I am writing yoJi to voice my support for the Technical ASsistance Grant
Committee's response to the EPA's action plan for clean-up of the Summitville Mine Site. I
-encourage your department to work with the TAG Committee for a thorough clean-up
. operation with SL ycitizen input. Thank you for your consideration - Sincerely, Susan Sawyer
. [Letter; undated; address given] .
.
Comment 23: ..' . . .. '.
Dear Ms. Laura William~, I am writing concerning the SUDIIIIitville miiae clean-up. I attended. .
and appreciated the m'eeting on Oct. 12, where the EP A presented their progress and future
for clean-up, and the TAG presented their answer and their suggestions on how to improve
the current trend. I have heard and read both sides of the issue. I, as do the residents of this
community, appreciate the work and the concern that the EPA has shown to clean up this
mess. Receiving Superfund status at such a fast rate was excellent. We are really grateful to
the organization. My concern, as most of the community's, is the'form in which the clean-up
is being performed. Some ~gs were done in obvious haste due to the situation and the
consequences are now being observed .le.: the.Reynolcls.adit.plUg .and.the .chandlel'.adit leak.... .
The .best thing to do, I believe, is to sit back and really assess the situanon before any more .
miStakes are made. The TAG has gone up there, researched the situation, consulted with .
experts and presented a cfifferent point of view. I listened to both sides (EP A versus TAG) 'and
came to the conclusion that the TAG had much better and faster resllLlts than the current
. method. I was much more cOmfortable with the rese2n:h done by the TAG group, seeing.that
it was done more in depth and with well experienced experts. The cost, being of great .concern
to many, would also be less if you reviewed the TAG group's point of view.. There are many
that say that this river has always been polluted. Most of these people do not reside close to
this river or even in the vicinity. Many live in other counties. I, as many other people in this
community did, fished, not only in this river but also on Terrace Reservoir, not too long ago
(1984-85). This river has not always been polluted. Maybe it's had it's ups and downs, but
it has never been dead. . Not only do fish not exist any more but algae can't even grow any .
longer. I ~ stating this because I have heard of people wanting the EP A to pull out, saying
.that this river has always been polluted. These people do ~ot know the facts and magnitude
of the damage that can occur and won't see into the future at what will happen to this valley
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. .
if nothing is done~ I really hope that you really take careful consideration OD aU OUi' I~tters,
and take the TAG group's suggestions seriously and implement their ideas. TJuuik you for
your time and hope you will have another update meeting soon. Sincerely, Nitschka ter Kuile .
and Steven Miller Home and Land Owners, 1/4 mile from Alamosa River.' [Letter; dated Oct
20,1994; other data not given] . .
.
Comment 24: . .
Dear Ms. Williams: I have reviewed the TAG committee's recent newsletter and have
discussed the feasibility studies that were done and submitted to the E.P.A. with a TAG
committee member. I would like to comment. First, I would like to tell you that our farm .has
been in our family for five generations. It is irrigated with water from the AJamosa river'
which flows through our farm. My husband and I worked for over forty years' to purchase
various parcels of land to make up what is now. the present 435 acres. It would be a severe
financial loss to my family and to the other farm families here to be forced to abandon our
farms should the. water quality of the Alamosa become incompatible with safe crop and
livestock production. I feel the TAG committee has «Jone an excellent job in their feasibility
. stUdy and in the suggestions they have made. I urge the E.P.A.. to consider water treatment
to become a top priority and to take the TAG committee's suggestion to build a water
treatment plant at the bottom of the mine site, rather than to continue with the current
treatment plan, which is not only more costly, but would delay the treatment of the water in
time to prevent damage to thousands of acres offarmland. Sincerely yours, Leola T. Miller
. (Letter; dated October 20, 1994; addi-ess given] .
EP A RESPONSE TO WRa:rm:f C0MMF.Nl:S..RECEIVED FROM
CITIZENS AT LARGE OF THE SAN .LIDS VALLEY
. . ,'. '''-, '., :' .. .' ',~: .;.
EP A will address citizen written comments' inone'rCspODSe~" An . but one 'of the citizen ~mm~ts
expressed direct concern with water quality issues as related to water quality conditions in the
Aiamosa River resulting from mini~g activities at the SUminitville Mine. Many citizen
co~ents received expressed support for the TAG committees' recommendations, particularly
regarding the location of the ~g on:"si~ Water Treatment Plant'and associated costs.
. .
. .
EP A appreciates the fact that citizens have t&cen the' time to attend the public meetings 'and"
review the proposed plans and recommendations. EP A feels that citizen input is a 'component of
the decision makine process and the concerns raised regarding water quality are valid and .
deserve consideration. EPA further recognizes the time and effort expended by the TAG to
evaluate the proposed plans and develop constructive recommendations. As with citizen
involvement, EP A realizes that impartial technical assistance provides value in the decision
making process. .
.
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EP A is also cOgTIi7.ant of water quality issues which are central to human health, agricultural
. ~pacts, and activities related to fishing, reCreational or otherwise. EP A agrees with citizen
concerns especially as they relate to water quality. .
-- .
It is the intent ofEPA to integrate recommendations made by the TAG into the final
consideration of alternatives. These may be especially pertinent to specific elements of the Site
Reclamation oPtions. In a letter from the Forest Supervisor of~e San Juan/Rio Grande National
Forest dated October 17, 1994, the Forest Service expressed agreement-in-principle with the
preferred alternative #4 for site reclamation, stating that "it certainly seems to be the most
reasonable and cost effective in terms of restoring the area to a productiv~ capacity".
The letter also stipulates' that, pursuant t~ the current Master MOU (Memorandum of
Understanding) between EP A and the USDAForest Service, the Forest Service agreed to
!'provide expertise related to natural resource tn~n~gement and protection... ". In response to the
proposed plan for site reclamation, the Forest Service has offered expertise, "particularly in the
area of soil/surface reclamation," based upon its "considerable experience in conducting high
elevation reclamation." EP A feels that recommendations made by the Forest Service are
valuable and will be carefully considered in final selection of specific elements of the .
reclamation plan, particularly those relevant to revegetation.
!{egarding the alternatives for water treatment, EP A recognizes TAG concerns in discriminating
between Alternative 5 and Alternative 6 and TAG suggested modifications to Alternative 6. .-
EP A further recognizes similarities between the two alternatives. EP A acknowledges TAG
efforts in acquiring coSt estimates from potential vendors. Relevant to costs for constructing a .
. new water treatment facility, EP A is COgTIi'7ant of potential difficulties associated with acquiring .
broad-based cost estimates from potential vendors who mayor may not be as familiar With site-
specific conditions. Site specific conditions can dramatically affect proposed costs regardless of
the experience arid intentions of potential cODstnictors..~Howe.ver,:EPA will take-IAG - . . "", , '
recommendations under advisement and continue to seek comment from TAG members.
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2.4
Summary and Response to ARARs Comments .
Comment 1:
Commenters noted that Section 3.2 of the Water Treatment FFS - Applicable or Relevant.
and Appropriate Requirements - states that the NCP allows waiver of Applicable or
Relevant and Appropriate Requirements (ARARs) for inte~ remedial measures that do
not exacerbate site problems ~d do not interfere with the final remedy. The WTFFS
implies in Section 5.0 - Detained Analysis of Alternatives - that interim remedial measures
that do not fully meet interim water quality numerical standards may be acceptable
provided the waiver provision is applied. The waiver provision or its use in this instance is
not adequately addressed relative to its potential impact on the selection of a preferred
alternative and the.final remedy. .
ReSJ)onse:
EP A agrees that the inclusion of the waiver discussion in the WTFFS is confusing.
Accordingly, EPAhas made it clear in Section 1.5.3.1 of the Water Treatment IROD that
the cumulative effect of the interim remedial actions should allow EP A to attain surface
water quality ARARs. No surface water quality ARARs are being waived in these
IRODs.' .
Comment 2:
Another commenter questioned the elimination of. biomass and ultrafiltration alternatives
from further elevation in the WTFFS and IROD. The commenter argued that these
alternatives should ~ot be eliminated from consideration because, without establishing.
ARARs, EP A cannot be certain that "further contaminant removal may not be
warranted." Similarly, electroplating is elimiDated for detailed alternative analysis since
the "~urrendY.1ISed technology does not produce a concentrated liquid waste stream." The
commenter argues that the .WTFFS.should,have.co~ider.ed. the..possibilityofmodif>in.g.~' ~ '" . .
current treatment processes so there would be'a concentrated waste stream acceptable for
electroplating and metals recovery.
ReSJ)Onse: .
EP A established the sitewide ARARs that must be met in the ARARs Addendum to. the .
HLP FFS. EP A mcorporated these ARARs by reference to the WTFFS as well. While
EP A agrees that this approach may have confused the commenters on the federal and
. state law requirements and regulations (or portions thereot) that were applicable or
relevant and appropriate to the various IRODs, each IROD now contains a separate and
complete discussion of the ARARs that must be met by the interim remedial action
selected. .
Since the sitewide ARARs had already been identified in the "ARARs Addendum to the
HLP Focused Feasibility Study Report", this further refinement of ARARs as they relate
.120
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to each of the IRODs represents only a minor change to each FFS and Proposed Plan.
Consistent with its "Interim F~ Guidance on Preparing Superfund Decision
Documents", OSWER Directive 9355.3-02 (June 1989), EP A has determined that this
minor change will have little or no impact on the overall scope, performance, or cost of
each alternative as originally presented in each FFS or Proposed Plan.
The commenter should also note that EP A may elimin::!~ interim alternatives on the basis
of cost if other interim action alternatives are effective and satisfy the interim objectives
and goals. EP A elimin::ttP.d the biomass, ultrafiltration, and electroplating alternatives on
.: the basis that the cost were grossly excessive when compared to their overall.. .
'.-. effectiveness. See 40 C.F.R. s 430(e)(7)(iii) and "Guidance on Feasibility Studies Under
CERCLA," EP A 540/G-85/003 (June 1985). . .
Comment 3: : - -.
A number of commenters Doted that the ground water ARARs are also )poorly defined,
causing EP A difficulty in determining whether groundwater ARARs can be met by EP A
remedial activities. These commenters challenged EP A's adoption of surface water quality
standards for ground water resources, citing a lack of data. Commenters noted the fact
that surface water consists of snow melt and storm water runoff, plus baseOow .
contributions from ground water sources. The commenter argued the Site has historically
exhibited high total dissolved solids (TDS) in the ground water and' that EP A has not
adequately characterized other background water quality conditions. Water quality data
from surface water sources typically shows less TDS than from groun~ water tributary
sources. The commenter believes EP A has failed to account for this data in selecting
ground water quality standards. . . .
.
ReS1)onse: .. " : . .- ... . ..' .
EP A has determined that the classification system prescribed by the Colorado Ground
W ~ Stan~ is applicable or relevant and appropriate to assignment of standards to
groundwater at Superfund sites within Colorado. Since the Colorado Water Quality
Commi~ion has yet to classify the Sitewide groundwater, numeric ground water for
COPC standards are not currently applicable or relevant and appropriate to ground water
quality at the Site.- The interim ground water ~ve standard adopted by the Colorado
Water Quality Control Commi~on on July 29, 1994, however, is 'applicable to the Site.
This standard, which became effective on August 30, 1994, requires that the ambient
water quality as of January 31,1994, continues to be met. This ARAR will be met by
compliance with EP A's interim action levels and with all surface water quality ARARs,
as discussed in each of the !RODs. .
. EP A, like the commenter, moreover, recognizes the hydrological interconnection between
the surface and ground water flows at the Site, particularly during baseflow periods. EP A
.expects, therefore, that once the CWQC completes its use attainability study and .
121
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classifies Site ground water, this classification will be applicable to the Site. This ARAR
will be attained by the final remedial action( s) for the Site.
Comment 4: .
Commenters question EP A's use of the most stringent stream classification - that of
Segment 3b of the Alamosa River - as the controlling surface water and ground water
quality ARAR. They state EP A has adequately explained why it has selected this stream
classification as the "controlli1ig" standard. Further, commenters argue that the numeric
criteria based on the most stringent stream classification does not account for the lower
classifications of other stream segments or for high background levels of copper, zinc and
other hazardous substances in the Wightman Fork -..d Alamosa River which are the result
of naturally occurring oxidation and transport processes acting upon highly mineralized,
nnmined and unprocessed rock in the area. EP A, they opine, cannot remediate water
quality below natorally-occuning background levels. Lastly, commenters argue that the .
State erred in designating Segment 3b of the Alamosa River as Class 1 Cold Water Aquatic
Life, and that this standard can never be attained because of background levels of metals.
They suggest t4at EP A waive this flawed classification based on the technical .
impracticability of achieving tJlese water quality standards and the State's failu,re to
consistently apply them, as evidenced by the creation ofNCLs in the permit and 1991 .
Settlement Agreement. . . . .
Re~onse:
. .
First, the commenters should understand that despite a Class 2 designation in Terrace
Reservoir (Segment 8), Segment 8 carries hardness-based TVS as the ambient standards. .
Because the hardness in the AIamosa River decreases with increasing distance. from the
water treatment plant at the Summitville Site, the ambient water quality standards in
Terrace Reservoir (Class 2) are more stringent than those assigned to Segment 3b (Class
I). . .
The commenters should also .note that the CWQCC originally proposed to upgrade
Terrace Reservoir to Cold Water Aquatic Life Class 1 but declined because of limited
data. In tact, review of Exhibit 12 to November 1,1993 hearing held by the CWQCC in
Alamosa, reveals the intention to collect needed data and review suitability for upgnu;ie to
a Class ~ designation. .As stated in the HLPFFS, at this time EP A believes that .
employing the Segment 3b standards will contribute to attaining Class -1 uses in Terrace
Reservoir and should contribute to attaining the existing, more stringent, hardness-based
TVS assigned to Terrace Reservoir. .
As the commenter is aware, the re-evaluation of water quality standards in Colorado
streams, rivers and reservoirs is an ongoing process controlled by the Colorado Water
Quality Control Commi~ion (CWQCC). In its discussion, EP A specifically. recognized
~e inconsistencies and concluded that the Colorado W~ Quality Standards (CWQs) for'
122
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Segment 3b of the Alamosa River, as the applicable ARARs, will serve as the nUmeric
interim remedial action goals for the Site.
..
At this time EPA does not have a basis for usurping the CWQCC authority to determine'
appropriate classification and water quality standards for the Alamosa River and its
tributaries. As additional data is gathered and the effects of the interim actions are
quantified, it is within the CWQCC's authority to address all of the issues identified in
these comments. Until that time, EP A will use the existing standards as numerical goals
for the remediation. '
In the HLPFFS, EP A made its intention to attain surface and grOund water quality
, ~ ARARs at Segment 3b of the Alamosa River clear. The attainment of the ARAR for
Segment 3b will be monitored using a "bubble" approach at the downgradient boundary
of the Site, monitoring point 5.5 in the Wightman Fork (WF 5.5). In this way, no single
interim remedial action alone is expected to bear the burden of ARARs attainment.
Where the action-specific ARARs associated with interim remedial actions at the
Summitville Site require identification of an ambient-water-quality-based-end point ~
NPDES point source permitting), the applicable CWQSs for Segment 3b are established
using a model to back calculate compliance at WF 5.5. This modeling resUlted in EPA's
establishment of interim action levels (IAL).
.~ . . -
As noted in the HLPFF~, given the active interchange typical of alluvial ground water
and surface water in high mountain valleys,EP A has determined ~ attaining ,
compliance with surface water quality ARARs and the ground water interim narrative
standard will protect bot!1 surface and ground waters. This interchange will only compel
ground water cleanup to the extent required, in combjnation with other actions, to attain
ARARs at the'point ofcomp~<;e (WF':$.~~) ~c;iJhe~bYJ~~t the standards established
for Segment 3b.
The commenter should also be aware that the background concentrations of metals and
, acids have been considered. At the triennial review of the Rio Grande Basin the
Colorado Water Quality Control Commission{CWQCC) did recognize that background
metals concentrations in Segment 3a can be attributed to natural acid mine drainage from .
Iron, Alum and Bitter Creeks. Consistent with those findings, the CWQCC promUlgated
standards in Segment 3b which reflect the elevated background concentrations and the
wider pH range documented in Segment 3a. EP A believes it has made its reliance on the
CWQCC's work very apparent in the table on page 3-6 ofHLPFFS (see the values for
chronic copper and chronic iron).
EP A did not participate in the development of the NCLs. These negotiated numbers are
not duly promulgated and they are not the result of applying site specific data to duly
promulgated NPDES requirements (i&.. mass balance, low flow, etc.) to establish a .
123
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.'
discharge ~t. The NCLs may indicate the appropriateness of a waiver at some tim~ in
the futme, but at the present EP A will reserve judgement on the Use of and scope of
waivers.
The EP A believes that, as an objective, the p~tection of the Alamosa River as habitat for
a diverse range of cold water aquatic life is appropriate until the combined effects of the
interim actions come into effect. Although it is impossible to preciselyquanti.fy, EPA
believes that when the combined, beneficial effects of the IRODs are realized, ARARs
. will be attained in Segment 3b of the Alamosa River.
At that time, EP A will be able to better quantify the results and determine if additional.
action or waiver is required. Likewise, the CWQCC will have another opportunity in
three years to evaluate the results of the interim RODs 8n.d use itS own use attainability
authorities and ground water site-specific classifications to adjust standards accordingly.
- . ." ,.
124
,
.-
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. ".,..,
. .... .
.- """ ...,..
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"
2.5
Summary and Response to Reynolds and Chandler Adit Quesdol1lS
"
. -
Although the Reynolds and Chandler Adit system is not a part of the current focUsed feasibility
$dies, EP A recognizes the actual and potential contribution that this syStem may provide to
overall A1vID cont:.mination at the Site. Of the fom FFSs, the Adit system is of most importance
to the Cropsy action since it is known that precipitation - approximately 72 million gallons per
, year - and ground water were funneled by the Mine Pits into the historic underground workings.
The Adits previously drained this water (now ground water) from the mine workings which are
interspersed throughout the sulfide ore body. Contact with the sulfide ore, resulted'in the'
transformation of the natural precipitation/ground water into, AMD. This A1vID then exited the
Reynolds Adit and flowed into the Wightman Fork stream.
As part of ongoing emergency activities, it was determined that the continua! generation of A1vID
from the Reynolds Adit could be substanttally reduced by plugging the Adit system. (See
Attachment F to Summitville Action Memorandum #2 dated January 28, 1993.) This would
result in the re-establishment of the historic ground water table, thereby el1minatiJ1g oxygen from
the mine workings! Adits. Concurrent evaluation of alternatives to address the Cropsy Waste Pile
included moving the CWP to the Mine Pits from which it was 'originally excavated. Overall
evaluation of the two ~ons (Reynolds and CWP) strongly favored the filling and capping of the
Mine Pits to prevent water infiltration through the sulfide ore body. .
If the evaluation of the two actions had been unfavorable, it is likely that the Mine Pits would
have needed to be regraded and a drainage notch constructed to reclaim the area. The movement
of the waste piles to ,the Mine fits, therefore, has actually resulted in a cost savings overall since
. the CWP remedy meets the needs of both portions of the Site. In addition, the reduction in
volume of AMD generated by CWP and the Adits system will result in the decrease of Water
Treatment required at the Si~e and, therefore, costs for this third action. Evaluation of the Adit
plugs and the re~liShirient ofthegrourid:watei.iableJS.angomg.and'llie information:', ".,.:..
developed will be incorpoI:ated iD,to RIlFS documents to support a separate Reynolds Adit/South, .
. Mountain ground water ROD:
The evaluation of the two actions was discussed in Attachment F of Action Memorandum #2 and
section 5.0 of the EEICA for the Cropsy Waste Pile, et al. An interim project report on the
Reynolds and Chandler Adit plugs was released on 'October 12, 1994. Each of these documents
is included as part of the Summitville AdmiDistrativeRecord and is available to the public. '
"
Comment 1:
The discussion in all the FFSs regarding AMD concentrations! volumes attributed to
various sources should have provided a detailed analysis of the c:hemic:al mass balances
associated with water quality in and adjacent to the property [Summitville Site]. .
125
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.-....".. ...
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.,
Re~onse: .
As Tables 1-4 of the FFSs plainly demonstrate, there is not a steady release of chemicals
over time with which to develop chemical mass balances. The bulk of the contaminants .
. are ,released during periods of high surface water flow such as spring snoWmelt or large '
storm eyents. As discussed. in section 1.3.2.3 of the FFSs, such an attempt i:S further
complicated by the varying nature of the geologic features encountered at the Site. To
attempt to develop a chemical mass balance for each chemical and geologic feature for
the various time frames does not add any greater understanding of the risks presented by
the Site. .
.
Comment 2: .
There is. concern associated with backfilling of the Mine.Pits (with CWP, SDI, and BMD
waste ~aterials) since the data suggest that the Mine Pits and th~ Reynolds Adit are
hydraulically int~rconnected. . Because of this hydrogeologic:aI connection, a greater
understanding regarding the geoc:hemic:al interrelationship should have been undertaken
prior to commencing backfilling activities.
The combined impa(;ts of implementing these two actions is still ~addressed, despite the
fact that the combined efforts could weD be the reason that another or other alternatives
wouldbepreurre~ .
Re~nse:
EPA agrees that the hydraulic interconnection between the Mine Pits and the Reynolds
Adit is an area which bears special attention. If the ground water table - as a result of the
Adit plugging - were to rise above the level of the Mine Pits, then the relocated waste
piles could be subjected to a ~ saturated condition. . Because of this concern, EP A
placed a continuous three-foot (finished thickness), highly-impermeable clay liner on the
bottom and all sides of the Mine P.its....P.Iacement and.Subsoquent~m~
-------
." - --- . " ~ . ." -"
. -."- - .-
~
1993 and 1994 will also be neutralized. '
.
Should the waste piles become saturated despite the design and construction safeguards
described above, any AMD generation within the Mine Pits would take place under
saturated conditions in ,~ high pH environment (high pH as a result of dissolving the lime
kiln dust). As with the ore body, this saturation would result in the elimination of oxygen
from the waste piles. This lack of oxygen would prevent the generation of AMD. While
a more detailed g~chemical discussion may be useful for actual design considerations, it
can generally be understood that the sulfide ore body below the Mine Pits presents the
highest AMD generating potential for the entire Site. If saturated conditions can
minimi7.e the AMD reaction for the sulfide ore body, then the same conditions will also
minimi7.e AMD reaction within the lesser sulfide-containing waste materials.
Comment 3:
This section [1.4.1.3 ofthe'CWP FFS] indicated that the Reynolds and ChandierAdits have
been plugged, but that the long term effects of plugging the Reynolds Adit and Chandler
Adit, and the consequent rise in the South Mountain water table have Dot been, determined.
" '
EP A indicated in its response to comments on the EEICA that a state-of-the-art
groundwater flow model that accounts for flow in fractures is being developed in order to
perform such evaluations. However, the Reynolds Adit was plugged prior to completion of
such a groundwater flow model evaluation and any publication of resuMts of such
evaluations. '
Re~nse:
The intent of the "long term effects" statement was to convey that EPA does not
definitively know the' actual1ong-term' effects-which the plug~gyyill'achi~ve ~ce
plugging was only recently completed in March 1994. However, the referenced model
~ been able to provide an approximation of the resultant ground water table. At this
time, a report ~n the findings of this model is in the final stages of review prior to its
release to the public. ' '
The development of the model was never eXpected to be completed prior to commencing
plugging activities. Instead, it WaS anticipated tbatthe model would be Used to study the
- effects of changes in site conditions (Le., removal/remedial actions) on the ground water
and Adit system. The model has only recently achieved a relative level of accuracy and is
now being evaluated based upon actual field conditions. Because the Adit pluggings ,
were conducted as a time-critica1, removal action, no formal public review process was
required, though the alternatives analysis for the Reynolds Adit has been a part of the
public record since January 28,1993.
127
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"
Comment 4: .
Plugging of the Reynolds Adit should have beenevalu2;lted as a long-term solution at the
Site rather than an Interim Remedial Action (IRA). Plugging of the Reynolds'Adit could
cause the following: (I) increase of the water table into the Mine Pits, (2) groundwater to .
exit the mountain via another shaft or adit (as was the case with the Chandler Adit), and/or
(3) the creation of additional point sources of Acid Rock Drainage (ARD) through seeps.
.
Re81)onse: ,
As discussed previously, the Reynolds and Chandler Adits were plugged as a time-
critical, emergency removal action. However, this does not imply that the plugging of the
Adits is considered to be interim in nature.. After initial consideration by EP A of the
three po~tial effects as listed by the commenter,' EP A felt it best to evaluate the impacts
to the ground water table and the actual performance of the plugs as a whole system. As
more about the South Mountain grotmd water regime is known, then a final decision
regarding the regime can be developed for long-term considerations.
Comment 5: .
EP A apparently has not performed adequate groundwater investigations to evaluate the
, short- and long-term effects of the Reynolds Adit plugging. Becaus~ of the complexity of
the groundwater flow syste~ at the Site, as rela~ed to u.cture flow and the hydrogeologic'
significance of the mine workings and adits, a groundwater flow model is necessary to
evaluate rises in the groundwater table and the potential for significant groundwater
discharges through existing adits a,nd shafts. Such modeling efforts must take into account
the effects of fractures on groundwater flow characteristics, groundwater recharge'
primarily through the Mine Pits before and after filling and capping, groundwater
discharge seeps, and other significant. hydrogeologic boundary conditions such as the
underground workiDgs. . '
. . ...~. ... ....
. ... --."' '. . .. .
Re~nse: ,
EP A agrees that the South Mountain ground water regime is complex in nature and can ,
have significant impacts upon the various actions discussed for the Site. As a result, EP A
has directed the development of a state-of-the-art, three-dimensional model with
assistance from the Office of Surface Mining. Each of the parameters identified by the
commenter and other considerations have been incorporated into development of the '
model. The model has only recentIyachieved. a relative level of accuracy and is now
being evaluated based upon actual field conditioDs. It is anticipated that the model can be
developed into a predictive tOol for evaluating future 8c,tions to be taken at the site.
Comment 6:
As anticipated by individuals commenting on the EElCA, plugging of the Reynolds Adit in
February 1994 apparently caused discharge of groundwater through the existing Chandler
128
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'-..."
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..
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.----_u .--..
fl.
.
Adit thus providing another source of ARD. As a result, EP A plugged the Chandler Adit
in March 1994. Shortly thereafter, the plug began leaking low pH metals-laden waters. An
e~planation for the failure of the Chandler Adit plug is not discussed in the FFS. . Failure of
the plug could be primarily a result of one or both of the following flaws in establishing the .
plug design parameters: 1) failure to use conservative hydraulic parameters, such as using
the maximum possible hydrostatic head expected at the plug that would result from
plugging of the Reynolds Adit; and 2) failure to select suitable competent rock for keying
the plug. This section also mentions that corrective measures are planned .for the Chandler
Adit, however, no specific discussion. of the nature' of the contemplated corrective measures
is provided.
Res:ponse: . . -.' 0 . .
Concerns regarding potential discharge from the Chandler Adit once the Reynolds Adit
was plugged did re~t in EP A including plugging of the Chandler Adit as part of the
removal action. However, the work for both Adits was conducted in a concurrent fashion
and was not based upon actual discharge observed from the Chandler. . 'J11e Chandler did
not fail until May 23, 1994, which is a sufficient amount of time after construction for the
plug to have .b~n fully effective. .
EP A agrees that the subsequent failure of the Chandler plug is likely to be associated with .
the plug design or the SUITOunding rock conditions. The corrective measures for the
Chandler are not discussed primarily because the plug failure was still being evaluated.
This assessment effort was initiated in November 1994 and it is anticipated that work to
repair or replace the Chandler Adit will be completed by Spring 1995.
Comment 7: .
EP A should not repeat the same mistake. of~rep.i1gmng~e~~~ancller ~dit.'wi~o~*.. 0" .
performing the appropriate hydrogeologic investigatio~ and evaluatiou. Replugging the
Chandler Adit may cause, as was the case in the Reynolds Adit plug, water exiting out of
another adit or shaft or significant hydrostatic pressures in the mountain that would cause
the development of multiple point sources via seeps at the base of the mountain. As
indicated above, the Chandler Adit is presentlY discharging low pH me1tals-rich waters
directly into Wightman Fork. It is not known why EP A did not open the valve in the
Reynolds Adit to reduce or preclude flow from exiting the ChandlerOAdit and treat this in
the PITS facility prior to discharge to Wightman Fork. This demonstrates a failure on
EP A's part to develop an overall environmental strategy at the Site, as opposed to a
number of disconnected and uncoordinated individual actions.
From an emergency response standpoint, it may have been appropriate to keep the
Reynolds Adit open since water from the Reynolds Adit could be readily treated.
129
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. ".
Re~onse: . . .
Based upon the short" success during the time that the Chandler Adit was functioIial, it is
unlikely that ieplugging of the Adit will result in discharges from other aditslshafts. The
. ground water model being developed tends to support this conclusion. However, it is
known that historic seeps did exist on South Mountain and it is reasonable to expect that
these seeps would redevelop. Even so, the rationale for plugging the Adit system was to
flood the mine workings and thereby eIiminl'lte oxygen from the reaction which generates
AMD. This will result in the gradual improvement of the South Mountain ground water
and, therefore, the water quality of the seeps.
.
The design for the Reynolds Adit included two separate plugs with piping betWeen the
. plugs. A valve which would allow EP A to drain the water behind the two plugs was to be
. installed once the second plug was completed. After observing the better-than-expected
performance from the first plug, EP A determined that a second plug would be a .
redundant expenditure and it was eIiminl'lted from construction. As a result, the
capability to open the valve - as originally considered - did not exist at the time that the
Chandler began to discharge to the Wigh1Jnan Fork. This valving capability has since
been inStalled and EP A has been treating the Chandler discharge at the PITS facility.
Rather than a lack of an overall environmental strategy for the Site, this incident is more
representative of the extreme physical and riming realities presented by the Site. Overall,
discharge from the Chandler Adit produced less flow and less copper concentrations than
experienced from the Reynolds Adit during the same time ftam~.of.the previous year.
Comment 8:
Plugging the Reynolds Adit may not, in the loug term, reduce acid mine drainage flows and
may turn out to be a very expensive experiment. Also, this interim action may actually
exacerbate site problems and, thus conflict with the National Contingency Plan. .
Re~nse: . - .. .
Base upon current data: gathering efforts and the reCent predictive capability of the ground
water model, EP A has determined that plUgging of the Reynolds Adit will result in a
reduction of contan,.inl'lnt ~rt from the Site. Therefore, these actions will not
exacerbate Site problems or interfere with the final overall site remedy. However, should
monitoring of the. South Mountain ground water indicate that the plugging is actually .
exacerbating Site conditions, the (now installed) valve within the Reynolds Adit can be
opened and treatment of the water initiated in the PITS. .
',,' . ." . . . ,. . '.., .. .., . . . . . ..;. ...., ,. .~.. ". .; '.
. .
. .
. ' ','. '- "
. . ",,'
Comment 9:
It is stated that "In 1993 and 1994, Emergency Response Removal Actions (ERRA) were
. taken to reduce contaminant load in untreated Site water. This was achieved in part .
. hy._prevention of AMD Oow from undei-ground workings-" Plugging the Reynolds Adit
130
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.'.._"- - ._---
,
probably did not reduce the' contaminant load in untreated Site water.
..
,H no immediate reduction of contaminated water flows was expected, what waS the
rationale for the precipitous action in 1993 and 1994 regarding plugging of the Reynolds
Adit? Alternative actions and consequences of combined actions could have been evaluated
on sound scientific bases thus'providing for recommended alternatives with higher
expectations of achievements for interim remedies and final overall site remedies.
Res.ponse: . , ,.'
In the spring of 1993, discharge from the Reynolds ~dit reached a peak flow of 763
gallons per minute with supersaturated concentrations of copper. Due to trea,tment
capacity limitations at the PITS facility, approximately 600 gallons per minute of the
discharge 9vert1owed the holding pond and escaped untreated into the ground or
" overflowed,into the nearby creeks. While this occurred over a limited 3-4 week period,
plugging of the Adits eliminated this highly contaminatP.d discharge to the Alamosa
drainage during the 1994 spring season. '
In general, each of the remedies disc,ussed in the FFSs are anticipated to have a gradual
impact upon water quality and cannot be guaranteed to dramaticaIiy improve conditions
over a short time'frame. Also, because of on-going water treatment, implementation of
the remedies is expected to allow EP A to discont;inue water treatment while maintaining
co~pliance with current water quality standards.
'Comment 10: '
This section [1.4.4.2 of the CWPFFS] ' does not provide an adequate description of the
groundwater flow conditions at the Site. A disc1l$sion of the prevailing groundwater flow
systems should be provided, iD:cluding the groundwater flow direction; permeabilities, and :',
storage coefficients. Also, there is no discussion provided on the regi0llal and'iocal
, hydrogeologic boundary co~ditions at the Site. It is unclear where the recharge and
discharge (seep) areas occur, and'the hydrogeologic effect of the underground workiligs
and their significance as a hydrogeologic boundary conditions ,are unknown. The text does
not discuss how plugging of the Reynolds Adit will effect the groundwater table conditions.
at the Site. If these conditions are unknown, at least a qualitative description is necessary.
.
The FFS does not include a description of the promised state-of-the-art groundwater flow
model that was supposedly developed to make these necessary evaluations. The model, as
well as information on model assumptions, model hydrogeologic boundary conditions,
should be included in an adequate FFS. The results of such modeling evaluations may
significantly alter the conclusions of the FFS with regard to replugging the Chandler Adit.
Such simulation would have pr~vided insight into the water table levels which could affect
, conclusions regarding the effectiveness of the selected alternative.
-------
"
In addition, EP A does not provide in the FFS a description of the proposed monitoring to
determine the effectiveness of the plugging in the short- and long-term. Evaluating the
effectiveness of the Reynolds Adit Plug will require monitoring of: '(1) fluctuations in the
water table; (2) existing seeps; (3) changes in flow quantity; and (4) changes in water'
. quality through these seeps. Also, monitoring the development of additional. seeps is
. critical Information regarding what EP A is currently considering as baseline for
monitoring and what methods will be used to evaluate the effectiveness of plugging is .
necessary to determine the impact of plugging these two adits, particularly with regard to
final site remediation. Further, information on the monitoring efforts currently being
performed by EP A to monitor the potential development of additional seeps.as a result of
the Reynolds Adit plug, and the results of such monitoring, are critical to evaluate the
effectiveness of the remedy. . ..
.
. R~nse: .
EP A agr~s that inclusion of the ground water model in an FS is essen$1 to evaluating
the effectiveness of a selected alternative for the South Mountain ground water regime.
. EP A also agrees that the results of monitoring for the various considerations outlined by
the commenter are essential in assesSing the impact of the Adit system plugging, .
particularly ~th regard to final Site remediation. However, the plugging of the Reynolds
and Chandler Adits and their impact on the ground water are not the focus of any of the
four FFSs provided for public review and inclusion of the . suggested information in these
FFSs is therefore inappropriate. Nonetheless, the modeling an4..monitoring 'efforts are
actively being pursued and EP A anticipates that this infon;nation will be incorporated into
future iUlFs documents to support a separate Reynolds AditlSouth Mountain ground
water ROD. These documents will be provided for public review and comment prior to
remedy selection:.
~
. .
.
132
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"
3.0
REFERENCES
'ALL REFERENCE MATERIAL AVAILABLE IN THE EPA ADMINISTRATIVE RECORD
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'1
1993/1994 ENVIRONMENTAL ANAL YSIS.SUMMITVILLE SUPERFUND SITE
COPPE" IlBSI /1884
'1883
JULY TO JUNE PERCENT OF 'ERCENT 0,
IAMPlE MAY JUN JULY AUG IEPT OCT NOV PEe JAN FEB MAR A'R MAY JUH COPPER LOAD CURllENT POTENTIAL
LOCATION IL8~ LOADING LOADING
FRENCH DRAIN lUMP
STREAM A 1163 1.121 831 1522 1.888 1183 "14 417 483 409 381 364 608 2.160 8.818
VAUEY CENTER DRAIN
FOS.' 1.138 1.418 282 181 188 120 147 122 104 83 60 31 632 1,801 3.434
DIkE I SUP
FOS.l 12 384 .ii:::;~!I\;~i~;::: 18 36 38 22 18 ,(.GIrt.:: '!~i:ff,ij~:;; ';i.~!~~~j::t :~t~:i:~~~ii;: 84 302 483
LPD.I . ROAD SEE'S
FOS.' 821 314 81 34 48 31 28 28 23 17 18 138 288 18 1&1
L'D.4 . 8 COMBINED
FRENCH DRAIN SUMP 3.181 3,840 1.823 1,813 889 829 4B1 492 438 314 391 492 2,238 2.410 12.289 2.12"
TOTAL FLOW
HEAP LEACH PAD
STREAM 8 8.348 4.031 181 333 34,9 148 78 28 4 I ':;!~;~!;~j:fi :,£~f.i::~;t~: 1.191 1.484 4.318 0.81%
CWP DVERFLDW..lIIIIO,OOI
CROPSY WA TER jj;:;::':\'; :;::,::;f::!:i,:;:;::;:::' i)M1;::~!'::. .:~;~t.~f:Jf;!f{ ::;::::~::~~fK }li~if~i~!;~r.: ';ji~:f~;~!i~~1 . ~i;i~~~1~;£1~~' '~:~:i~i!i~~;i;~!~:i.: 2.843 1.840 1.411 8,833 18.921 4.20%
TREATMENT PLANTI
HLP LEACHA TE 39.384 31.888 33.182 24,888 22.?D8 21.802 19,036 18.082 13.813 8.334 9,041 1.836 8.103 9.019 192.488 42.711%
UNfLUENT TO CO" : !
UNDERGROUND WORKINGS :
STREAM C 83.242 11 0.139 34.432 20.212 19.~1~ 12,3112 8.883 6.319 2.883 142 112 86 1.128 102.818 12.18% 22.80"
REYNOLDS ADIT-1AD.OI ~ i
PITS 12.110 1&.661 19.180 18.412 19.U~ 12.362 8,983 6.318 2.882 04 140 164 0 0 8&.118
IREYNOLDS ADIT TREATMENn ,
CHANDLER PORrA! '~:'::i:;{:::~~:::).;'. ~ ~~r:;il::;i}t :;:::;;ti~m~;t .:~:~~{:~~;::::~l ',:kh\)': .r~::~t:~~n:::" ;.~:??~:(::.} .'::,::::,:;::,',~:,: .=;:.:::::.;.:.:.;.:'::' t~:tf:f:;~ft: 11.164 83.188 88.642 89.13% 21.22"
: :'." ".::,,:..~:. .",':,:"",:,;':.:.,",
CRONY CREEK : ,
LPO.l 281 188 31 69 .31 28 1 0 .::;t1¥~I~){: ':;:if*:i.~it 't=f.;i'~j~:~~;t .;1~;~1~1:~:' 194 288 821
lEAST OF F. D. SU"." ':'f~}~;~t~ir:.
STREAM H 3.824 860 121 III ~~ &2 28 21 21 III 26 188 642 611 1.731 I.2J% 0.38.%
CRONY CREEIC
POND 4
S1REAM F 0 781 408 128 3~~ 18 81.)t:i;:i,;:;: ";~':.-:. :.:,:;,;:.:::,,::',' ,/:::\/;( ;i:;~:!j~:~:;;: 1,002 1,886 4.1108 3.29% 1.00%
....,... .
POND 4 DISCHARGE " ';"'";:.":.-
IOWA AOIT "...';"',' .:.' ';-::..';...:.:...;. :;:;':::::~;~;:::-;::.: :::};:;:~;:~~~ ~ "'::::.;:;.:~:.;::*'::- ;::;i:::~:;:;:~.;:~:': ::}l./;~.:'~-~. ::'~-;:lt/.::- ;.~::r:r:~~: :}ft}{f :{::t~:t~~f{ 31 223 NIM
.. . -.:.'.'-.-.-.." ':"':""':.:'::;:'C :..-:.:.:.:.-:.': ,;.";"",,,,-''''-':''-
OTHER CONTRI8UTOR8 TO WIGHTMAN FORK
STREAM 0 .. 4.436 3.804 1.281 1,1B8 1.1126 813 809 844 i];!,!;!!l,:iili:t ,;';:;:~:::;,~,'r :i;1,j~!:j~;~::" ::f:;!i!i~::' 4118 8.110 12.294 8.88" 2.13"
CLEVElAND CUFfS \
S1REAM E 3.389 3.486 888 97 31 .. '.:;:~;::::':.~::'::::.:': :!iiiffi::;lfi''',' ~~f~J.l?l 'i;::;i~'~~!rf:;' '!l~:;:I:f!: .,:11:~1Ir~ 1.1113 1.810 4.321 3.111% 0.88"
NORTH DUMP DRAINAGE : :t~~~lff:~~t : .~?:;:;:~ ~:~~:i:: ;-.
STREAM a 2.306 1.028 "-::.-:-:'.:.'...::.; :~:;'f:'::f=~;r .':fJi;!=:il~J: ,:fi,:!~;~;i.~ ::;:~~;;;:;:::,':'};, :~\:~1~f,r:!~} }~j1,;;~~::::!: x'~:r::';,:.:. :;r:!;j:r:::1'. ::::':~:~-~;;'::~,,: 818 231 1.113 0.81% 0.28%
CLAY ORE STDCKPILEISEEP li i~;~{f:1~}j~. .\t,tfF: {:!}irlf[~~r!.
TREA TMENT OISCIIARGE 23 411 31 22 28 32 21 13 11 0 0 0 8 24 189 0.14" 0.04 %
TO WIGItTMAN FORK
MONTlIL Y TOTAL OF 64.248 106.231 11.399 4.488 1.814 1.038 882 810 33 83 .3 82 18.161 84.830 131.204 100.00%
CURRENT CONTRIBUTORS
MONTHLY TOTAL OF All 111.89) 168.6BO 12.994 48,470 "6.113 36.836 21.196 2UJ4 18.788 8.866 12.411 10."12 33.088 114.332 460.266 100"
POTENTIAL CONTRIBUTORS ..-. ~~
...
WF.I.6 WIOIITMAN FORIt '41.438 11.181 20.1148 8.424 3.882 838 180 010 470 314 300 000 20.424 81.460 14' M7
-- ..---
Table 1 Copper Content - 81te Contaminated Water, 1993-1994 Record
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199311894 ENVIRONMENTAL ANAL YSIS.SUMMITVllLE SUPERFUND SITE
CYANIDE 11181 11814
-,'UoAI"" n.....,.. ur ':::::.::
IAWlI MAY JUN JUly AUG IUT OCT NOY DEC .IAN fEI MAli AI'ft MAY JUN CYANIDE LOAD CURIWIT
LOCATION 11111 LOADING. LOADING
'RiNCH DRAIN lUMP
URlAM A 440 142 .11 413 .41 392 114 899 841 122 4.0 109 III 399 '.411
VAUEY CEHTER DRAIN
FD'.' 48 38 18 7 7 7 14 8 3 . I 0 1 14 81
DIU I SEE'
FD'.' 8 "' ~;1\1~!f]~ill~~~;~ .0 8 21 12 17 :.,;.;.:.:.;.:.:.:.:-:-:.:.:. ~~lf.~j~~ifti~~ j';11I!tf1?:f::: j:j:;f1;iilr!:i 1 12 102
LPO.I . ROAD SEEPS ;tl~~l~i~~~t~i
FD'.J 0 ° 0 . 0 0 0 0 0 0 0 0 0 0 2
lPO.4 . 1 COMBIEO
FRENCH DRAlH SUMP U4' I.' liS '.017 '.11' .16 476 4'5 IIf f" 429 464 IUD 699 488 7.148 4.4'~
IEffLUENTI
IIiAP LIACH 'AD . III
srRlAM 8 0 0 0 ° 0 0 0 0 0 :,":':~~::::::~::~:::': :\!ijj~IIi~;;ii' 0 0 0
CWP OVERfLOW IIIO.OOI .~ :\~~;ir~~\~f;~i~:
:::;:;:;jt::( [.t::::\tt:: '::~:':;: :::~:::::'::::::::::::', ;:S:::,:,:;:::j::j;::.: .:.:.:.:-:..,;.:.:.:.:...;',' :;~j~~~~[~~~ltl:~: '~~lti\tI
CR.t:PSY WArER ;":.:':':':':':':':'.'.:' :~;~]~~l~tt~:~* ~:}:EW%: ::~.:::::::~~.:;;:;;:::.;. 0 0 0 0 0
, III ATMENTl'LAHn ::~*;k?~~~~r )1,'1!:;H.:.
:;:::::~:{::::;~:.::;:::: '::".,,"::::J:.'.::::::':'
H.I'.fACHArl Jf. fl5 11.09' 21U17 17.114 fI.592 'I.'" 15.779 'f.655 ".382 8.812 8.137 7.2/1f 5.221 1.121 118.717 11.14-
pNfLUENT TO COft
UNDEROROUND WORIIINO'
SrRlAM C 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 O.OO~ 0.0010
REYNOtOS ADIT 1A0.01 '
,ns 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0.0010
,IREYNOIOS ADIT TREATMENTI
CiIAND.ER POIIrAt ...'.::.::.,0:'" .?:::::;':::::;:.::':::::::::. ::~::;::::::;:~;:~':::::~:' ::: ::::::Z:~:::~~::::~:~;:~ ::~~~:;:;:::~:~::1~::. '::~'%,;W:,,:::,,:: ;::::::::::::::::~;::::y: :'j~:~~::~:~:::~:?::::::' ::::~'::h~}':~::::: '::::~:r:::~::::::::::~;' ,-:r:~~:::~:~::::~?;:: 0 0 0 0.00- 0.00-
CROPlY CRlEII
.1'D-2 0 0 0 0 0 0 0 0 ;i~t;~jij;~~(~~t:~~~ '~~~f,t\fr.t~ .t~@}~ft? '~~1~~0~1;~;; '~~1~i:y:~i.~~~!j~~' 0 0
lEAST Of .. O. IUYPI ::;::::;::::::~;~::t.:~;:;
SrREAM H 26 'Of , 17 ~ 0 16 0 0 , 0 I . 7 14 1.88- 0.03-
CROPSY CRUll
POND 4 . .. III .
SrREAM F .::: ',::';C,:::: I":::::?'?:(=:,:.:: 1.::\:~:,::;:t:::;:::1 \:::t::!:::::::!::I:::::::::i::\~:!::'::::t: I :'~~;\:::::::{:':I>:;:g::::::,:?: I"!':~!!;::~~'!\:~ .:::::::::,;:;:::,:::;:::.; ,'::/i:\::;;['.;!!\.:::! I';!!::~!!!:!'!!!~;:!::I ':::!.:#Nt1:: .:::'::'::::::i:!!:::::: I 0 8 t.02~ O.OO~
POND 4 OtSCHARGE
IDIVA ADlr 0 NIM
OTIIIR CONTRlIUTORS TO WlGIITMAN fORII
srREAM 0 I 0 0 0 II 0 0 .0 :~~!j;1ljj~~~tjij~r )f::~frr~r '.~~~lilij~l~f~jj~~t fii;:;1~;r-j;if~; 0 0 0 O.OO~ O.OO~
CLEVELAND CliffS .:?~:$:~:~::::::~:::
UREAMI 0 0 0 0 0 0 ,:~~~~j~~~j~~;tj{f.~~~~;; :t;j*ili;t~~~\r :r\~t~~;~~~frf ~~r~~j~f~~~1*~~; .....'.:,:.:.:.;.:-:.:,:.:.:,. ::':-:-:';';':':':0:';":':' ':':';0:':0:"':0;':':0:'.: 0 0 O.OO~ O.OO~
i::;MMiW: .~::.:;:.::~:::-::;:~:..: ~~!;~[t~~\~j~~~ti
NORT" DUIU' DRAINAGE ,ir:~~~~nr~:
SrREAM 0 0 0 r~~ij~~~1~~~~t.~~~;: '~~~~~i~~~jf.;~ffr~~~ :1~i[~;~~~f~~~r~~ ~rt~tl~r~~\~[j~I~: :::!ii\;:~\:Ii)i.1;::: ::~:;:~:;:;::~~:::;:;~:::: ~~~;~:~~~g~t~~~t:~ \;J;~*~l~~iji:f;~: ~:'fi!i\i:~!fj:: ~f~f~~lf~~J.;f:~~j 0 0 ° 0.01~ O.OO~
CLAY ORE STOCKPILIISEE. LI '~:~~(?~r:t~
'REA rAflNr DI'CIIARGI 113 184 .00 74 13 S9 14 43 18 0 0 0 31 I 17 722 12.08~ 0.43~
TO WIOIIT MAIL fORK
MONTH! Y TOTAL O. 180 288 .01 II II 107 70 43 18 I I 1 41 124 784 100.00~
CURRINT CONTRlIUTORI
MoNTH! Y TOTAL Of ALL 11.417 30.411 21.191 11.128 17.210 17.'41 11.'88 11.189 11.871 '.'41 '.101 7.7114 1.838 ... III 118.127 1oo~
POTENTIAL CONTRIBUTORI
Wf.8.. WIGIIrWIN FORK 1.118 1.128 228 401 117 12 184 III 81 0 0 .2 .80 2.888 4.118
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Table 3a Site Surface Water and Treatment Plant Flow Rates, 1993-1994 Record
1993/1994 ENVIRONMENTAL ANAlYSIS-SUMMITVlllE SUPERfUND SITE
flOW RATE IGPMI
.,
11883
IAMPLe
LOCATION
'RENCH DRAIN lUMP
srREAMA
VAUEY CENTER DRAIN
FOS.'
DIKE 1 SEEP
FDS.2
LPD.1 . ROAD SEEPS
FDS.!
LPD.4 . & COM8INEO
FRENCH DRAIN SUMP
IEffLUENTI
HEAP LEACH PAD
STREAM B
CWP OVERFLOW '1110.00'
CROPSI' WATER
TREATMENT PLANT!
HLP LEACIIA rE
INFLUENT TO CO"
UNDERGROUND WORKINGS
srREAM C
REYNOLDS ADIT 1A0'O'
Plrs
IREYNOLDS ADIT TREATMENT!
CHANOLER PORTAL
CROPSY CREEK
LPO-2
IIEAST OF F. D. SUMP!
STREAMH
CROPSY CRUK
POND 4
srREAM F
POND 4 DISCHARGE
IOWAAOIr "'..' ..,...,...
OTHER CONTRI8UTORS TO WIGHTMAN fORK
srREAM 0 202
CLEVELANO CUfFS
STREAM E
NORTII DUMP DRAIt/AGE
srREAM G
CLAY ORE STOCICPIU 'SEEP LI
":)/'::':':';:::\;';:,':,:.: '.<: ,'.::
MAY
,.
JUN
11884
DEC JAN fEI MAR APR
74 73 70 70 78
3 1 1 1 I
2.805
JULY
AUG 8£" OCT NDY
68 82 71 70
& & 3 4
3 3 3 3
12 12 13 11
103 8& 70 70
70
&8
&7
12
40
28
8
1
18 :f~!]!:i::1:ill:~i:ii:,
2IB...
10 7 8 &. &
2&
2&
14
1111
180
124
70
70
70
384
181
47 18 111 8 4 2 ..
'::
"11TI3RT""","""-"W"'''-''~ "-"'V-""".'.... ~,"'''''''''"''w- '0
~ii:;:W:;:!;::1;::;t;~ ;:;;}:W!'!::;;::::::.7:;:::,;:;:;;,:::;;:.::.{f:f ,-: 18 74
877 888.. 847 774 874 839 880 1121 848 8111
::,,':'::.':::-;.'::";:' :
884 723
4811
783
388
272
229
180
118
.:~.: .
I'>'{;'::;:?:';:
97
48
8
7
74
113
182
218
231
180
118
87
88
87
72
" .:;: ::~~~: '.: :\",' ::~:;;=r{::,::;::::.:::. :.:#:;~::::~:::if::?:
:':~'::':::::::;",:::::;::::::,
'0";':"""';':"'""'';
.:{:~;':::::;~;~::{i".. ..::; ':~~:>::":.':.>;-. ..:)):{::~~:}.
J ;:\::::r:};~::::-~::::
';:;';:{::;:;::';:';;=:';
':; :~:~:;:~;;:~':::fri:
::(:::;'::i:j::g':;:.
I ;
28
28 2 & \ 2
2.&08 843 327 ' ; 239
7118 11& 318 138
2 i-!i::;;\i:'!1..!i:i:f:;:::ti!;~:;f!i;\:.it ';i:ii;::i;;ii::!!r i;:;:~J:;::~:~i:i;:
,:.'::!:*::1;~:!;i;i:'~:;:;:;:\:;;'r;f!i~l;::
104
8S
112
52
38
41
w"",: '."..'..,, £l~;f!!~\11 E
':1 ,TiS:' x,,:_~==
",,,,",..""',"
';.;;..:;.::::",,:
'.~::::::}:;:;':;:::~:}p:
".'.'..",',",',',".'.' ',',",",
::;.::~.;::..:'.:::'::::::;::::;
,:':: ;:;:;::~t:~:::~t:~r,
1118
112
83
88
284
282
87
13
4
49
IIII.j:~;i~,;~~:;~j6 Y&J.:i;i~i::g;
-. -,..,..,... .."...." ..7-... W, .M. ...-. . '::;;Wj~~::*::':I:i;:;' '::i;;J.:~;iii~:;;;
=~ti~==_ur~¥
':!:Ji~E~;::~:::I;~'..
~t.:;:)%:;;~;!i;:'
:::':,:.:<;,.' : 'hi';?::::,:,:
.':J!i~~:;:t;M;; :,;'1!,f;:'::iij:::::i, .:;11~t;r~i!:~:.r
','0:"',',,"";':;";;"
{?f;f~:1;t~~iij:;;~~~;
MONTHLY TOTAL 0' 3.762 4.440 1.093 186 440
CURRINT CONTRI8UTORS
MONTlILY TOTAL 0' ALL 4.83& &.8&7 2,123 1.700 1.428
POTENTIAL CONTRIIIUTORS
IVF.I.& wIGHrAfANFOR/C 1&.8118 13.823 3.3113 2.328 1.131
182
1011 8S U 38 41 88
1173 807 818 738 874 817
.-.
708 483 344 233 2811 1.278
1.214
1196
MAY
87
e
811
88
1.348
";:{t:tJ::i;:):.
3.08:1
3.8811
10.483
132
HIGH flOW lOVV flOW
JUN . IGPM, 'OPM)
17183 TO 81841 17/83 TO 81841
118 132 &8
38 38 1
20 20 2
13 14 &
181 18& 70
44 47 ,0
1112 1711 74
7110 774 834
88 388 8
0 237 0
&11 &11 388
28 28 2
2.450 2.480 38
786 848 4
134 HIM HIM
188 188 33
314 314 2
41 41 37 :
!
..;'.'::;i:.:',";':; ':;"::;::;;/.::,!:;';:;/:;:,'};:;::::', "';:1::::ir'i;':U;!};;:::;,fi.:;'
4.3G6 4.3G1I 3G
8.484 &.484 730
12.&20 12.1120 233
14
4
10
1811
28
1711
&34
o
388
13
848
20
109
264
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1883/1884 ENVIRONMENTAL ANALYSIS.SUMMITVIlLE SUPERfUND BITE
flOW IGALLONSI
OCT 'II A;R '14 tAGH,fLOW LOW fLOW
IAIIPLI MAY 'II JUN 'n JULY 'II AUG 'II IIPT 'II NOY 'II OIC 'II .IAN'M fll '14 MAR '14 MAY 'I' JUN 'I' IGALLONI. IGALLONI,
LOCATION IJ;III TO 1114' IJIII TO 11M'
fRiNCH 01lAlN IUM'
STRIAM... 2.1".120 I."MOO 1.114.080 1.113. JlO 1.8J8.400 U",440 3.014.000 3.103.110 UIUIO 1,811.400 UI4.800 3.118.100 1."'.410 1.141.440 8.811.480 U3UIO
YALLlY CINTIR DRAIN
IDS., un.loo 1.211.800 387,110 113,100 ~11.000 133.120 nuoo 133.120 44.840 40,320 44.840 '3.100 12UIO I.8n .110 1.83),210 40.120
DIU' 8(1'
IDS.' 44.140 820.100 113,120 128,800 133.120 12UOO 88.280 - nl.810 841. no 848. no 88.280
LPD." ROAD IIiPS ~, . '::,
IPH I. \18.000 1.010.000 12',110 113.110 ~18,4oo 880.120 478.200 448.400 312.480 241,920 113.100 111.000 448.400 140.000 12UIO 2\8.000
IPD'4 . I COM8INID
IRINCHDllAIN SV'" U40.140 1.201.000 1,131.380 4.19J .920 '.104.000 U14.100 3.024.000 3.124.800 1.124.100 1.822.400 3.124.800 3.188.400 8.288.400 1.811.100 8.218.400 1.821,400
.lffLUfNn
HrA' LIACH 'AD _.'H'_~
UREAM. '.248.820 '.818.080 1.088.080 0
CVIP OVIRfLOW/IIIO DOl '. " ~~ '.( ''',,'
CROl'Sr WA rlR ;, 18.811.110:;" ::io2:::.~~ - ~ 2.~~LI.~~0 2J.~IO.400 ;:'34::I~'.'IO 28.\18.800 21.81U80 1~8:0:1.:. 28.0IU20 2::::::::: 2:::::::: J.III.140 1.888.400 J.III.140 3.188.100
TRlAT"'I"T ....ANn
H,,,rACHAJI U.UJ.JlO 32.400.000 34.111.180 lun.JIO
!NfIUlNT TO COP!
UNDIROROUND WORKINOI !
SlRlAM C 11.881.040 12.811.100 n.JII.720 12.141.010 8.~8I.loo 1.011.200 1,140.100 4.130.080 1.011.884 111.110 101,021 244.010 1.481.880 n.JII.no 244.010
REVHOL08 AD'T IAD'OI
PI" 3.103.110 4.111.100 I.IJO.IIO UI\.120 10.U8.4oo 8.038.200 1.140.800 4.130.010 1.010.110 2.JOI.440 3.114.010 UII.200 0 0 10.211.400 0
RIYHOID, ADII TRlAIMlNT'
CHANDlrR_rA .~.:::~m,:x..A::i;::x:: ~::::"' ~' ..?..~:::. x '. '":..'.£::~' :.,' " .:'," .::::;. ~:(.:. ,, : m:~}.\~ ,M ;::"::.:. >:ff:'!!': -:~m:«'~. ',~ ~~~~.ro:~~~ t .: :~J':):':(~~ 11.412 180 24.114.240 24.114 240 11.4n.110
'. ,....
CROPlY CRUK
11'0.' 1.110.140 1.208.100 ".280 223.100 ',88.400 H'~- 880.320 1,211.800 1.212.800 11.400
.IAIIT 0' ,. O. iUMPI
STRIAM H 121.211.200 101.1'1.600 28.703,820 IU9UIO :10.,124.100 4.142.880 2.810.800 2,71J.810 2.121.280 1,411.120 1.820.240 1.848.800 80.011.440 105.831.310 105,831.310 1.481.820
CROPlY CRiEIt
POND 4
5 fREA..' ;tiij~tt.~itt 11.081.200 1.111.100 14.18"'20 1.~11.8oo 1.4n.120 112.100- 4UI8,720 11.069.600 42,318.120 nuoo
POND 4 DISCHARGE "
, '
IOWA ADlr :~::~::~$~~::~~*:;~~:::;~(~~{: :: :- J'. '...', J'. "" ~ .:' .. ~... ,.::~ :~~.» . ,''i-.':~ :-:.;-:: :::~" .-:'. ..,~~ :" ..' ... .', .:...':: ~.:::: t .:..:~:. ..:..~ :", ,)." " , :' ~:i " :'" ;::::.:: t:. '~...;?::J' ',:. ' 882.1001 I J1I 6201 HIAI H/A
OflllR CONT".IUTORI TO WlOIITMAN ,0Rl
STREAM D 9.0n.210 UIJ.800 2.321.210 UOI.120 2.141.800 I.81U20 "'28.800 1.&1"'10 4.188,710 :7.241.104 7,248.804 1.425.600
I~UVILANO CLIffS ~~~Mf!WM
SJRlAM r 12.8n.JIO 12.112.400 2.810.880 880.320 112.800 18.810 11.11"'80 13.114.800 13.164.800 16.8&0
HORfH DUMP ORAI/IAOI ~~
SJRIAM 0 2.187.160 2.811.200 r "";;0:".;",',.:-:..;.:' 1.111.180 1.761.870 1.761.820 /.651.680
OM TOCIPILI PI
MONTIILY TOTAL Of 187.4".210 111.108.000 ".341.120 11.481.100 11.008.000 8.102.180 4.118.200 4.411.180 2.321,210 1.411.120 1.820.240 3.844.100 118.J32.320 188.118;384 181.111.384 1.411.620
CUMlHT CO"'Rl8U'DRI
MONTHLY IDTAL Of ALL 220.281.400 244.182.400 84. no. 120 71.881.000 II .103.200 14.1J0.140 42.011..100 40.488.480 38.48J.114 28.171.120 38.001.412 11.188.280 nJ.8I1.040 231.188.084 218.111.084 28.8J8.620
"".", WHJHrMAN'DRIl "4.101.120 "8.11'.100 141.ln.120 101.121.820 ".1".200 11.002.410 10.881.100 22.ooJ.620 18.188 110 1.114.880 11.118.100 18.112.800 411.111.120 141.101.120 141,101.820 1.184.810
Table 3b Site Surface Water and Treatment Plant Water Volume
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Table 4
Contaminaat Coateat at High and Low Flows -
£deatified AMD Streams
..
Slre8m:. i ~~.;; ."
Stnam B
Stram A
Rcco~Da~".:~"
.... -
High Flow
UI08I93
Sf'..4I93
Low Flow
9108193
1:M6I93
. C1"M~~".--':.:,~Ff¥~~;:"~:'
... .'
..
" "
'.
High
14.4
m.5
Low
62.1
1
Scn:am C
6/10193
S/13J93
.. '.'
: ,.,
910
14
. Stram D
" Stram E:
'Stream F
.
,'.
6101193 6108193 611r'..I93
lUGS193 912tJ93 &110193
"," - .~.;..;. ."
..'.::", -.
~~7:1';:
348
19
m
1
~~~ :~~,';:;<~~~~ ~;:~~~.,~J~i::~ }:~r~;~f~~
Wach
56.6
iZ
Low
~1
63.54
35.Z
15.4
:Ira~~~~~~~~:;.~ ~~t\?::<~~,~~ '~t,:t{?:,: .,:,',:-:, ~~:~;~,:~~,
High
:97.6
1:140
Low
.uB..l
793
'Toaatf~e;t:ffi~:::w::':,,<- ;';:},:';'~'"";''' ~<::..'!' ~<:"-
High Flow
:S.:5
NR
Low Flow
10.95
~
1738
368.4
-.,;--
'.
".:: ~
~
NR
:::}:-~~/?;:'~ ~~~...
72
40
16.6
66.09
";":::..' - "
105
24
--_.__..'
- ----
S~~
, ":--
'::_"~,
r.::.".
611SJ93
11/11193
:.:-.'~~
,,'-..~~
1116
0.5
~;7_"::.,-::.;:>::::" ~.,...
~\:.::~"~' '.:"'.'" ,"'''....'
'.~.. ~~":~.::~!.~. ...~~. "~
2151.1
800
=;..:.: :~;::~~:: .. .:-:
..
..
<.tH
<.01
10
65.53
:.:..,~ ;i:/. :;:>.:;t ~t.
,. "":~;'';:,;;',,-::~'. ''':'~~II;.'
...'$'~, \0-"", ..~'C"'~" -~..
-::, 'J":"':'-::-:' : :-.": ~ "~''':''':''.:.. -'
1109.:5
55.5
54.75
:6':1
..;.~~:.:.~~
<.01
<.01
Stre2m:~ .:,~~~::.~:' ::.: StnaDA,: :StreamC' StiaaD Streallll'£ StraarE'~, StraaGi:"; StreallJ H , FI);~
Reconfi~atc=:-"~$"~, ... ,- ';~:-:", .. " ,, " MY""" '. .,~~
~ .. :-',.. ' . .~..~ ~
. '.. "
H~b Flow 612:194 6120194 No lafOl'lll8cioa Available 6I21J94
Low Flow ~-5194 5/01194 5103194
Zinc. digested' - ,: :.' ' ,",' "' .. o:;~~i
'--.'
Higb 101 9.73 105
Low 15.98 &4.1 4.99
Aluminuar..dig. -.,
Hil:h l&.u 154.5 992.1
Low I .u 96-. 60.13
1..:1
636
44'7.5
310.8
16.88
..
.... :
-'.:.:;..r~' __0
-. ... .~~o~~~~~,~.
I 0.017
I <.01
NR
~
Aluminum aad Zinc Conteat at High and Low Flows ~
IdeauCed AJ.~,StreaJDS""~'
.
All cODcearr:uiollS. ~
-------
.~ . ..
35
... 30
ID
5 25
-
f '20
.: IS
ID
8: 10
o
o S
o
24-
May-
93
.'
.,
-+-t-t-+
8- 29- 13-
. Jun- Jun- Jul-
93 : 93 . 93
.
. ,
Table 6
. .
COPPER CONCENTRATIONS AT WF-6.6
29- 11- 23- . 7-
.
Jul- Aug- Aug- ~~p-
93 93 93 : ~3
I
. .
I-f-I-I-H-i-f-I-+-
29- 14- s- 16-
Sep- Ocl- Nov- Nov-
93 93 . 93 93 .
Date
..
.,
j.
j .
I I I l-++-t-t-t-
2- 21- 4-
Mar- Mar-. Apr-
94 94 94
I I I I
2- 23-. 20-
May- May- Jim-
94 94 94
"
-------
)
.
3
Ii
;a 2.S,
en
E 2,
oj
'a LS
'c
.~ I
u
! .0.5
o
...
,Table 6
TOTAL CYANIDE CONCENTRATIONS AT WF-6.6
.'. .
o. I' I I H-t-
24- 8- 29- 13-
May- Jun- Jam- Jul-
'93 93 93 93
, I , I I", 'II .+=
29-. 11- .23-' 7~ i 29- 14-
Jul- Aug~ Aug- Sep~ Sep-. Oct-
93 93 93 93' 93 93
+- t-:H-
S- ,16- 16-
Nov- Nov- Dec-
93 93 93
. D~te
+-t-
6- 24-
Jan- Jan-
94 94
IS- 2- 21-
Feb- Mnr- Mnr-
9494 94
.
"
-H-t
4- 2- 23- 20-
. Apr- May- May- Jun-
-------
; .
,,'
: ~: .: ~'
;.i j" .
'I:,
;'1
"
-j .
I,'
Standards. Requirements.
Criteria. 1.lmltations
OROUNDW A TER:
Nalional Primary Drinking Waler
Siandards
Nallonal Secondary Drinking
Waler Siandards
Maximum Conlamlnanl level
Ooals
Colorado around Water
Siandards
..
..,
Table 7
Potential Chcmlcal Specific ARARs
Citation
40 C.F.R. Part 141, Subpart 0
pursuant to 42 U.S.C. if 300g-1
and 300j-9.
State: 5 CCR 1003-1 pursuant to
C.R.S. A 25-I-l07(1)(x) "
40 C.F.R. Part 143, pursuant to '
42 U.S.C. n 300g-l(c)nnd 300j-
9 '
40 C.F.R. Part 141, SubpPrt F,
pursuan~ to 42 U.S.C. 1,300g-1
State: 5 CCR 1002-8 n 3.11.0-
3.11.8 '
Description
BSlablishes numeric standards
for public water systems.
Maximum conlaminant levels
(MCls) are established to
pr~tect human life-time drinking
water exposure.
Bstablishes aeslhel,lcs-relaled
standards for public waler
syslems (secondary maximum
conlamlnanllevel).
BSlablishes drinking waler
qualily goals set at levels of no
known or anticlpaled adverse
heallh effecls, wilh an adequRle
margin ohafel)'.
Establishes a scheme for
Identifying groundwater
specified areps, for classificalion
of Colorado ground water and
provides numeric standards.
Also, establishes an interim
narrative slandard for all
unclassified ground water,
supplementing stalewlde
standards.
Potentially Applicable or
Relevant and Appropriate
No
No
No
Applicable
,
Comment'
No public water supplies
are present, Ihe Siale of
Colorado has
, comprehensive ground-
water classification system.
including numeric standards
equivalent to (MCls). See
secllon 3.2.1.
. Protects aeslhetlc character,
not relevant to protection of
human heallh or
environment.
No non-zero MClOs set at
levels less than MCls were
'identified for contaminants
of concern.
See section 3.2.1.
-------
.
.
Tobie 7 (continued)
Chemical Specific Criteria To-Dc-Considered (TDC)
,
Standards, Requirements, Potentially Applicable or
Crflerla. UIIIUalions Cltatloq DescrlptiOlI . Rclevant anti Appropriate Comment
RCRA Groundwater Protection 40 CFR ffi 264.92 - 264.101 Establishes standards for ground No The State of Colorado has
Standard (RCRA GPS) water quality related to RCRA comprehensive ground-
State: 6 CCR 1007-3 hazardous waste facilities. water classification system.
Including numeric standards.
equivalent to MCLs and
RCRA GPS.
SURFACE WATER:
Colorado Water Quality State: 5 CCR 1002-8, ffi 3.1.0 - Establishes standards and Applicable See section 3.1.1.
Standards 3.1.17 classifications for Colorado
surface waters.
Federal Water Quality Criteria 40 C.F.R. Part 131 Sets criteria for surface water Relevant and Appropriate See section 3.1.2.
quality based on toxicity to
Quality Criteria for Water, 1986, . aquatic organisms and human
pursuantto 33 U.S.C. g 1314 : health.
J.
Allt
National Primary and Secondary 40 C.F.R. Part 50, pursuant t~ 4~ Establishes standards for Applicable See section 3.4.
Ambient Air Quality Standards U.S.C. f ~409. I ainbient air quality to protect
public health and welfare
State:. C.R.S..~ 2~-7-108, 5 CC~ (Including standards for "
,.
1001-14. particulate matter and lead). I
40 C.F.R. Part 61, Subparts N, 0, Sets emission standards for '
National Emission Standards for No Air emissions are not.
Hazardous Air Pollutants 1) pursuant to 42 U.S.C. f 7412. designated hazardous pollutants. anticipated after
State: C.R.S.g25-7-108, 5 CCR construe lion activities are
1001-10 complete. See section 3.4.
! '
" '
(;
-------
.q.
..; .
'.
):~ ~ :
~ '
:1 ~'
: (.~ .
\0'.:
,I
.'
f;;'
Advisories 10 be
'Considered and Guidance
SOilS:
Toxic Substances Control Act, PCB
, Spill Cleanup Policy'
Interim Ouldance on Establishing
Soil lead Cleanup levels at
Superfund Sites .
..A
..
,
, Table 7 (continued)
Chemical Specific 'Criteria To-De-Consldered (TDC)
Citation
Description
52 FR 10688 April 2, 1987
'Establishes guidance cleanup
levels for PCB contaminant
solis.
. Established guidance cleanup.
levels for lead contol1.1lnated
soils.
EPA Directive 119355.4-02,
September 1989. . .
. .
To De Considered
CommeQI
Not considered
There is no evidence that
PCB spills have occurred.
Considered
See secllon 3.3.
-------
Potentially Applicable or
. Relevant and Appropriate
Table 7 (continued) .
Potent~al Action Specific ARARs
Citation
SOI.l[) WASTE DlSPOSA I. ACT ("SWDA ")
Guidelines for the Thermal 40 C.F.R. Pari 240, pursuant to
Processing of Solid Wastes 42 U.S.G.1690I, GlsQ...
Guidelines for the Land Disposal of 40 C.R.S. Pari 241, pursu'ant to
Solid Wastes 42 U..S.C.16901, GlsQ.;
Colorado Regulntions Pertaining to
Solid Waste Disposal Sites and
Facilities.
Guidelines for the Storage and
, Collection of Residential,
Commercial, and Institutional Solid
Waste
Source Sep~ration for Materials
Rec~very Guidelines
, .
.\
State: 6 CCR 1007-2, pursuant
to C.R.S.130-20-101 anti
C.R.S; IjO-20-102,~
40 C.F.R. Part 243, pUrSl!antto
42 U.S.C.1690I,~.' .
~O C.F.R. Pari 246, purs~ant to
42 U.S.C.1690I, ~
Descriptio..
Prescribes guidelines for
thermal processing of municipal
solid wastes.
Establishes requirements and
procedures for land disposal of
solid wastes.
Establishes requirements and
procedm'es for land disposal of
. solid wastes and the siting of
disposal facilities. .
Establishes guidelines for
collection of residential,
commercial, and Institutional
solid wastes.
Establishes requirements and
recommended procedures for
source separation by federal
agencies of resldentinl,
coinm'erclal, and Institutional
solid wastes.
. .
Potentially Applicable or
Relevant and Appropriate
No
No
No
No
No
...
i
,.
Comment
,
Thermal processing'will not.
occur. .
Disposal of mine wastes
and closure of mines aro
specifically addressed by
the Colorado Mined Land
Regulations. See section
4.2.
Disposal of mine wastes
and closure of mines are
specincally addressed by
the Colorado Mined Land
Regulations. See section'
4.2
Not relevant.
Not relevant. Creates no
substantive cleanup
-------
Potentially Applicable or
"elevont 'and Appropriate
Guidelines for Development and
Implementation of State Solid
Waste Management Plans
':",
Criteria for Classification of Solid
Waste Disposal Facilities and
Practices
Table 7 (continued)
Potential Action Specific ARARs
Citation
40 C.F.R. Part 256, pursuant to
42 U.S.C. 1 6901, ~
4~ C.F.R. Part 257, pursuant to
42 U.S.C. . 6901, ~,
,
"
Oeserilltion .
Bstabllshes reqilirements for
federal approval of state
programs to regulate open
dumps. '.
Potentially Apllllcable or
Relevant and Appropriate
No
Establishes crUel'la for solid
. waste disposal facilities and
practices. ;
No
Hazardous Waste Management 40 C.F.R. Part 260 : Establishes procedures and No
System: General criteria for modification or
; S.tate: 6 CCR 1007-~ Part 260 revocation of any provision In
parts 260-265.
Identification and listing of 40 C.F.R. Part 26i, pursuant to Defines those solid wastes' Applicable
Hazardous Waste 42 U.S.C. 16921. f , which are subject to regulation
as hazardous wastes under 40
State: 6 CCR 1007~3 Part. 26 I , C.F.R. Parts 262-265 and Parts
. pursuant to C.R.S. ,125-15-302 124,270,271.
" .
Standards Applicable to Generators ..40 C.F.R. Part 262, pursu~nt to Bstabllshes standards for Applicable
of Hazardous Waste 42 U.S.C. f 6~22 ' : generators of hazardous waste.
State: 6 CCR 1001-3 Part 262,
pursuant to C.R.S.t 25-15-302
...
"
Comment
Creates no substantive
cleanup requirements.
Disposal of mine wastes
and closure of mines are
specifically addressed by
the Colorado Mined Land
Regulations. See section
4.2. .
Creates no substantive
cleanup requirements.
Provides for the
Identification of hazardous
Wastes; ~sed to determine.
disposal criteria for sludges
&. spent process che~lcals
generated from water
treatment.
If hazardous waste are
generated onslte amt
managed offslte the
requirements are applicable. .
. Used 10 handle process
chemicals and sludge
management f~r water
treatment.
-------
,
"
Tobie 7 (continued) ,
Pote~tial Action Specific ARARs
Potentially Applicable or Potentially Applicable or
Relevant and Appropriate Citation Description Relevant nnel Appropriate Comment
Standllrds Applicable to 40 C.f.R. Part 263, pursuant to Establishes standards which Applicable I f hazardous wastes are
Transporters of Uazardolls Waste 42 U.S.C. ~ 6923 apply to persons transporting transported offsite the
haiardous waste within the U.S. requirements are applicable.
State: 6 CCR 1001-3 Part 263, If the transportation requires a
pursuanllo C.R.S. fi 25-15-302, mpnifesl under 40 C.F.R. Part
4 CCR 123-18 I 262.
Standards for Owners and 40 C.f.R.Part 264, pursuant to Establishes standurds which Yes See section 4.1.
Operators of hazardous Waste 42 U.S.C. fi 6924, 692S' define the acceptable
Treatment, Storage, and Disposal management of hazardous waste
Facilities State: 6 CCR 1007-3 Port 264, for owners and operators of
subparts D, C, D, B, F, 0, K, L, facilities which treat, store, or
and N, pursuant to C.R;S. fi dispose of hazardous w.aste.
2S-IS-j02
Interim Stahdards for Owners an 40 C.F.R. Part 26S Establishes standards for Relevant and Appropriate Establishes no substantive
Operators of Ilazardous Waste management of hazardous waste standards applicable or
Treatment, Storage, and Disposal State: 6 CCR 1007-3, PQrt 26S dnrlng interim stntus. relevant and appropriate to
. Facilities the IILP.
'. Standards for the management of 40 C.F.R. Part 266 Establishes requirements which No Not relevant to activities at
Specific hazardous Wastes and apply to recyclable materials the site.
Specific Types of Hazardous Waste State: 6 CCR 1007-3, Part 267 that are reclaimed to recover
Management Facilities economically significant
amounts of precious metals,
including gold and silver.
Interim Standards for Owners and 40 C.F.R. Plirt 267 Bstablishes minimum national No Part 267 regulations are no
Operators of New Hazardous Waste standards that define acceptable longer effective after
Land Disposal Facilities State: 6 CCR 1007-3, Part 267' management of hazardous waste February 11, 1983.
-------
"
r
,1."
'i"
I'
f\ ' "
"
'~" .
\
, \.
. "
. \
"
'i~ .
! ~. .
.,!'
~ :
:.:
Potentially Applicable or
Relevan. and ApprQprlo'e
Hazardous Waste Penni' Program
Undergroun~ Storage Tanks
. '
.
Cllatloq
40 C.F.R. Part 270
Tuble 7 (continued)
P~tentiQI Action Specific ARARs
D~scrlptlon
Establishes provisions covering
basic EPA permitting
. requirements.
State: 6 CCR 1007-3;Part 100
40 C.P.R. Part 280
, ,
Estabilshes regulations related to No
, underground storage tanks.
Potentially Applicable or
Itelevant and ApprQprla,c
No
..
.! '
Com men.
A penn It Is not required for
onslle CERCLA response
actions.
The use of or remediation
, of underground storage
tanks is not anticipated.
-------
..
.
Potentially Applicable or
Relevant and Appropriate
SAFE ORINKING WATER ACT
Underground Injection Control
Regulations
CLEAN WATER ACT
National Pollutant Discharge
Elimination System
Amendmenl to Ihe SeUlemenl of
July I. 1991 .
Effluenl Limilations
.,
..
Table 7 (contblued)
Potential Action Specific ARARs
Citation
40 C.F.R. II .144.12. 144.24.
and 144.2S. pursuant to 42
U.S.C. i 121 (e)(I)
, 40 C.~.R. Paris 122. 12S:
pursuant to 33 U.S.C. i 1342
! .
S CCR 1002-2. fit 6~1.0 t~
6.18.0. pursuant to C.R.S.;' 25-
8-501 '
July 21. 1992 agreement.
belween Co. Mined Recla~atlon
Board. Co. Mined Recla'matlon
Division. CO. Water Quality
Control Division. the E~ecutlve
. I
Director orthe CDPHE.a.,d the
SCMCI ':.
40 C.F.R. Part 440. pursuant to
33 U.S.C.' 1311' ':
. 5 CCR 1002-3. II 10.1 to
10.1.7. pursuant to C.R.S; f 2S-
8-S03 . .
Description
Establishes requirements for
injection of waste water inlo
wells and aquifers.
Requires permits for Ihe .
discharge of pollutants from any
point source into waters of the
United States including
stormwater.
ESlablishes Numerical Criteria
Limits for walerquolily for
outfall 004 (WF5.S) an a
compliance plan
f,
Sets technology-based effluent
limitations for point source
discharges in the Ore Mining
and Dressing Point Source
category. Also provides
exemption for release of storm
. waleI' where defined BMP
criteria are implemented.
Potentially Applicable or
Relevant and Appropriate
No
Applicable
Considered
Relevant and Appropriate
..
'It,
. I
I
Comment'
~
I
I
\
I
Underground injection is
not anticipated.
See secllons 4.3 and 4.4.
-------
Table 7 (continued)
Potential Action Specific ARARs
,
" . Potellllolly Apl)lIcable or Potentially Applicable or
Relevant and ApprQprlHte Citation Description Relevant and Approprlntc Commenl
National Pretreatment Standards 40 C.F.R. Part 403, pursuant to Sets standards to control No No discharge to a publicly
33 U.S.C. f 1317 pollutants which pass through or owned treatment works is
interfere with treatment anticipated.
processes in publicly oWlled
treatment works or which may .'
. contaminate sewage sludge.
(I' . Toxic Pollutant Emuent Standards 40 C.P.R. Part 129, pursuant to Establishes effluent standards or No The discharge' of specified
33 U.S.C. f 1317 I prohibitions for certain toxic pollutants is not anticipated.
pollutants: aldrin! dieldrin,
!... DDT, endrin, toxaphene,
. benzidine, PCDs.
Drcdgc or Fill Requirements 40 C.P.R. Parts 230, 231 Requires permits for discharge No No construction activities
(Section 404) ' of dredged or fill material into are applicable involving
33 C.F.R. Part 323, pursuant to navigable waters. dredging in water treatment.
33 U.S.C. f 1344' :
Marine Protection, Research &. 13 U.S;C.U 1401-1445 Regulates ocean dumping. No Ocean dumping will not
Sanctuary Act occur.
'
I
Toxic Substances Control Act PCD IS U.S.C. f 260S(e) . Establishes disposal No At this time It Is not
Requirements 40 C.F.R. Part 761 : requirements for PCBs anticipated that remedial
acllvilies will involve the
.' disposal of PCDs.
I.- . Uranium Mill Tailings Radiation 42 U.S.C. if 1901-1~42 Establishes requirements related No Uranium 10111 tailings are
Control Act to uranium milt tailings. not present at the slle.
42 U.S.C. f 2022
Surface Mining Controt and 30 U.S.C. U 120t-1328 'Establ!shes provisions designed No Not relevant. Creates 00
:.' Reclamation' Act to protect the environment from substantive cleanup
the effects of surface coal requirements.
mining operations.
,
. ..
,.'
.
.
-------
.
.
oJ
Table 7 (continucd)
Potential Action Specific ARARa .
,
Potelltlully Appllca61e or Potentially Applicable or
Ih:h:Vllllt ami Appropriate Citation Description Relevant and Appropriate Comment
Occupational Safety and Heallh Act 29 U.S.C. if 651-678 Regulates worker heallh and No While not an ARAR,these
safety. requirements will apply.
during Implementation of
remedies at the sile.
Federal Mine Safety and lIeallh Act 30 U.S.C. U 801-962 Regulates working condilions In No While not an ARAR, Ihe
underground mines to assure requirements will be met If
safety and health of workers. it becomes necessary to
access underground "tine
workings.
Hazardous Materials Transportation 49 U.S.C. U 1801-1813, Regulates trllnsporlalion of Applicable If hazardous materials are
Act, D.O.T. Hazardous Materials 49 C.F.R. Parts 107, 171-171 hazardous materials transported offslte these
Transportation Regulations regulations will be aUained.
Will apply to sludges or
spent or process chemicals
if determined hazardous.
,
Colorado Noise Abatement Stalute State: C.R.S. U2S-12-IPI, ESlablishes standards for No While not an ARAR, .
~ controlling noise. applicable standards will be
met during construction
activities at the Summltville .
site.
Colorado Mined Land Reclamation State: C.R.S. g 34-32-101 Regulates all aspecls of mining, Yes See section 4.6.
Act ~ and regulations, 2 (:CR. including location of operations,
407-1 reclamation, and other
environmental and
-------
..
Table 7 (continued)
. Potential Action Specific ARARs
Potentially AplJllcable or PotenUally Applicable or
Relevant and 'Appropriate CUallnn Description Itelevant and Appropriate Comment
Nlliionallllsioric Preservallon Acl 16 U.S.C. f 470 EPA musl accoul1t fQr Ihe Applicable A survey will. be performed
affecls of any acllon on any so thallhe Colorado Siale
40 C.F.R. f 6.301(b) properly with hlsloric. Hlslorlc Preservalion
archileclural. archeological or Officer may delermine If
3~ C.F.R. Pari 800 cullural value Ihut is lisled or pariS of the sile are eligible
' eligible for lisling on Ihe , for inclusion on Ihe Siale or
: State: C.R.S. U 24-80-101-108 Nalional Register of Historic National regislers. (See
Places. or Ihe Colorado Regisler section 5.2).
of Historic Places.
Archeological and Historic 16 U.S.C.f 469 ESlablishes procedures 10 Applicable A survey will be performed
Preservalion Acl of 1974 preserve hislorical and 10 identify data Ihal requires.
40 C.F.R. f 6.30I(f), archeological dala which mighl proteclion during remedial
be destroyed through alteralion activities.
of lerrain as a result of a federal
" , constrUction projeci or a
fede,rally licensed activity or
program.
llistoric Siles Act of 1935. 16 U.S.C. II 461 ~ Requires federal agencies 10 Applicable A s,irvey will be performed
Execulive Order 11593 . consider the exlslence and to idenllfy polenllal n~lural
40 C.F.R. f 6.30 I (a) location of landmarks on Ihe landmarks.
., . National Registry of Nalural
i .
Landmarks 10 avoid undesirable
Impacls on such landmarks.
Colorado Wildlife Enforcemeni and Slate: 'C.R.S. U 3~-1-101. Prohibils acllons detrimental 10 Applicable. During Ihe design phase of
Penallies " ',nWL wildlife. the remedy. consideration
" will be given to. 1,110
protecllon of wildlife.
4''''
'i
.
-
-------
.
Potentially Applicable or
Itelevant and Appropriate
Wildlife Commission Regulations
Fish and Wildlife Coordination Act
. Endangered Species Act
Coastal Zone Management Act
Table 7 (continucd)
Potential Action SI)ccific ARARs
. Citation
Siale: 2 CCR 40S-0
16 U.S.C. U 661-666
40 C.F.R. 1 6.302(g)
. ,
16 U.S.C. U IS]I-1S4~ : .
50 C.F.R. Paris 17.402
40 C.F.R. 16.302(h)
State: C.R.S. U 33-2-101,
I
. n.wJ.
~6 U.S.C. u 1451-1461
. Description
Establ'shes specific
r~qulrements for prolectlon of
wildlife.
Requires consultation when
federal department or agency
proposes or authorizes any
modification of any stream or
. other water body to provide for
adequate provision for
protection of fish and wildlife
resources.
Requires that federal agencies
Insure that a.,y action
authorized, funded, or curried
out by the agency Is not likely to
Jeopardize ihe continued
existence of any threatened or
.endangered species or destroy or
adversely ~odify critical
habitat.. .
Prohibits federal agencies from
underlaklng any activity that Is
not consistent with a state's
approved coastal :zone
management program.
Potentially Apl)lIcable or
Relevant and Appropriate
Applicable
Applicable
Applicable
No
.
.
..
Comment
During the design phase of
the remedy, requirements
for the protection of
wildlife will be met in the
Summitville Mine area.
Prior to modification of
water bodies appropriate
agencies. will be consulted.
See section 5.1.
A survey of threatened and
endangered species Is
underway. Prior to any.
action that would jeopardize
the continued existence of
any threatened or
endangered species or .
destroy or adversely modifY
critical habitat, appropriate
State and Federal agencies
will be consulted. See
section 5.3..
The site Is not In the
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"
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Potentially Applicable or
Releva"t and Approprlat4'
Wild and Scenic Rivers Act
,Executive Order on Protection of
Wetlands
Executive Order 011 Floodplnll1
Management
Rivers and Harbors Act of 1899.
Section 10 Pem1it
.
.
Table 7 (continued)
Potential Action Specific ARARs
Citation
16 U.S.C. II 1271-1287
40 C.P.R. f 6.302(e~
36 C.P.R. Part 297 :
Exec. Order No. II. 990
40 C.P.R. f 6.302(b) and
. Appendix A ; ;
Exec; Order No. 11.:988 ,
~ :
40 C.P.R. f 6.302(~) and
Appendix A : ! .
33 U.S:C. f 403 ~ \
33 C.P.R. Parts 32~-330
DmrIntiJm
Establishes requirements
applicable to water resource
development projec'ts affecting
wild. scenic. or recreational,
rivers within or studied for
, Inclusion In the National Wild
and Scenic Rivers System.
Requires federal agencies to
evaluate the potential effects of
actions they may take in
wellands to minimize adverse
Impacts to the wetlands.
Requires federal ngencles 10
evalnate Ihe potential effects of
actions they may take In a
floodplain 10 avoid. to the
maximum extent possible. the
adverse Impacts associated with
direct and indirect development
'of a n~odplain.
Requires permit for structures or
work In or affecting navigable
waters.
Potentially Applicable or
Relevant and Appropriate
Applicable
Applicable
Applicable
No
"
Commen,
The slle is nol a wild.
scenic. or recreational river'
In Ihe National Wild and
Scenic River Systems. It
will be delermlned If any
\ part orahe site Is Included'
in the Inventory of rivers
under consideration.
Wetlands will be
Inventoried and considered. '
Floodplains potentially
Impacted will be ,
inventoried and considered.
Surface water of the
Summltville Mine Slte'are
riot n"vlgable within the
meaning of Section 10 of
the Rivers and Harbors Act
of 1899.
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.
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i
Table 8
- Numeric Surface Water Quality Goals and ARARs
Alamosa River - Monitoring Station AR-4S.4
METAl,. SURFACE WATER. QUAUI'Y GOALS
Class 1 (1VS)
pH 6.5-9.0
AlumiDum. c:bro1Iic 87us1l dissolved, May 1 duough Septr.mbcoz 30 cmiy. For baI8DI:e of
year ChroIIic - Acute 1VS - 7SOugf\ dissahed
Arsenic, acuIe . SOug/\. total rcccm:rabIc, loday
Cadmium. c:bnmic 2.3ug1\ dissahed @ 2SOmgIl banIDcss
OIrome VL c:IInmic II ugI\ dissoIwd
Copper. c:bro1Iic . , 30ugf\ dissolved, based upon SSm pen:emi1e IIIIIbiem cIIIIa from segmcm
'" 3a
Cylmide SugIl. l-day
Inm. c:hroDic 12.0CI01IWL total recovenble. based upoa SSm pen:emile ambiem claD. ,
.' 14ug/l dissalwd@ 2SOmgIl bardDeSs
Lead. chnmic
~""!P'''- chnmic . lOOOug1l. dissoMd
Mercury. c:bnmic O.Olugll.lDlal recovenble
Nic:b:l. chronic 192ug1\ dissahed @ 2SOm!Vl1IIIrdaI:ss
Silver. duoDic, !rOUt O.36ugl\ dissahed@ 2SOm!Vl banIDcss
ZiDc. chnmic 230ugf1 dissahed @ 2S0mWl bardDess
Note: Based upon WQCDfinding of 2S0mgIl bardness.Reservoir.
.:. .- . ... ~ .'
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Table 9
"
EV ALVA TION OF ALTERNATIVES
CrUerla Alternative No. . Alternative No.2 Alternative No. J Alternative No.4 Alternative No.5
NO AcrlON CONTINUI TREATaIENT-NO CONTINUI TREUMENT.WITII CONTINUE TlU:ATIIIENT.WITIl CONTINUE THEA TIIIENT.WITIl
AMD CONVERSION , AIIID CONVERSION ; AIIID CONVERSION AND NEW 'LAN
CONTAINMENT
Overall Protection of Does not provide any Protection of human Treatment of additional Containment of surface Containment of surface
Human Health and the measure of protection. health and the AMD Improves overall water assures the water assures the
Environment environment would protection of human maximum possible maximum possible
continue at the current health and the protection for human protection during
level. environment. health and the interim remedial
Activation oftheMRP environment during actions.
preserves this Interim remedial
protection during peak actions.
flows. :
Compliance with Does not meet It Is anticipated that It is anticipated that It Is anticipated that It is anticipated that
ARAR's ARARs. ARARs will be met ARARs,will be met this alternative meets this alternative meets
after source control after source control. ARARs. ARARs.
Q~ions are complete. actions are complete.
Long-term effectiveness None Properly designed Properly designed Effects of interim Effects of Interim
and permanence. ,~i~posal ..rea can ; disposal area can remedial measures in remedial measures In
prpvlde adequate provide adequate reducing containment reducing containment
<;Optainment of residual containment of residual load In downstream load In downstream
sludges mcludlng sludges Including waters is unknown~ waters Is unknown.
~applng as fin~1 action capping as final action
to .prevent to prevent
re~obilizatlon. remobilization.
Reduction oftoxicity. No .reduction of Transported Transported. This alternative This alternative
mobility, or volume toxicity, mobility, or contaminant volume is contaminant volume is encompasses treatment encompasses treatment
volume reduced. Metals reduced. Metals of all contaminated of all contaminated
mobility In residual mobility In residual point source. point source
materials Is low. This materials is low. Peak discharges. discharges.
Alternative Is not flow in excess of 1000
effective at reducing GPM would discharge
total contaminant into Wightman Fork.
toxicity, mobility, or
volume.
-
..
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...
.
.
Table 9 (CONTINUED)
EVALUATION OF ALTERNATIVES
"
. 'i
Criteria Alternallve No. I Alternative No.2 Alternative No. J Alternative No.4 Alternative No.5
NO AcrlON CONTINUE TREATMEN"-NO CONTINUE TRUTMENT-WITII CONnNU! 'rREA TIII£NT-WITII CONTINUE TREATMENT-Wil'li
AMD CONVEItSION AMD CONVERSION A~ID CONVERSION AND NEW PLAN
CONTAINIIIENT
Short-tenn effectiveness None No significant No significant, Short-tenn benefit of Short-tenn benefit of
additional impact to additional impact to this alternative is this alternative is
: human'health or the human health or the containment and containment and
. environment during the environment during the treatment of all point treatment of all point
short tenn. short tenn. sources of AMD- sources of AMD-
: metals removed would metals removed would
not degrade not degrade
downstream waters. downstream waters.
Implementability Shut-down and Easily implemented All materials and Implementation This alternative is
mothballing of the becaus~ all the required services required are involves only on-Site implementable.
Site required periodic faciliti~s are currenlly available on Site. activities. Materials Construction ofnew
assessment and in use.; Conversion of CDP and and services exist or AMD treatment plant
inspection required. ' : MRP to treat AMD is are available. required.'
; required.
Cost Capital $892.300 $9.9:46;900 $9.79S.500 $9.785,500 $15,024.S00
.- .;
Capital Cost \ ; $1.610.000
Construction
Treatment and $S5.600 $S5,6~0 $9.488.500 $8.724,100 $5.834.500
Assessment (1995-1996)
. ,
Present Worth of Annual $240.900 $18t9.00 $24.411.700 $IS,469,200 $17.136.700
Treatment and
Assessment
Total Capital and $1.131.200 $10.123.800 $32,207.200 $26.874.700 $32.161,200
Present Value Treatment !
and Assessment
:!.
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~.
Table 10:
Cost Estimate for Alternative #1
.
Cost Estimate Spreadsheet
Cost Basis: Dismantle, Mothball and Shutdown of all three
water'treattnentplants CDP, MRP and CWTP.
Weekly T~ent and Assessment of Compliance Point AR 45.4
.,
Total Capital Costs
Demobilization Costs Unit Number Unit Cost . Cost
Shutdown of CDP and Pumphouse (4 weeks) LS 1 $208,578 $208,576
Shutdown ofMRP (3 weeks) LS .. 1 $148,277 $148,277
Shutdown ofCWIP (2 weeks) LS 1 $55,606 $56,606
Vehicles Demobilization LS 1 $25,000 $25,000
ICP Demobilization LS 1 . $6,000 $6,000
Stationary Filter Press - Demob LS 1 $2'5,000 $25,000
Mobile Filter Press - Demob LS 1 $6,000 $6,000
Site Support (4 weeks) LS 1 S41t838 S416,838
Subtotal $892.297
TOTAL Treatment and Assessment eOS'FS. "'. ..,. '..', . ,'..". .," r. ,'" ,- ........ ..'. ".: ..,. . " "
.. ." .. '...," .' .~ .' -" ...'
Weekly Trea1ment and Assessment of.AR - 45.4 . Unit Number Unit Cost Cost
Technicians . Hours .416 S40 $16,640
,Laboratory Analyses Each 260 $150 $39.000
Subtotal $55,640 "
Present Value (@ 5% for 5 yean) $240,892
Total Present Value Cost (Treatment and Assessment) 51,133,189 .
-
--..."". ..."'"
" .
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....' '-...~"-"
., .
. .'" .
~'I(...,... -
...~.-."';-
.- -. -- ..
.. .....- ...
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Table 11
.
Cost Estimate for Alternative #2
Cost Estimate Spreadsheet
..
Cost Basis:
. Treat HLP Lear.hate and drain Heap by August 1995
- Dismantle, mothball and shutdown COP and MRP .
Treaanent and Assessment of compliance point AR 45.4 weekly after
September 1995 for four years. .
Total Capital Costs
Unit Number Unit Cost Cost
HLP Leachate Treaanent 1000 Gal. 170,000 $32.18 $5,470,600
Shutdown ofCDP and Pumphouse (4 weeks) LS 1 $208,576 $206,576
Shutdown ofMRP (3 weeks) LS 1 $148,277 $148,277 .
V chicles DemobiliDtion LS 1 $10,000 $10,000
Site Support (51 weeks) LS 1 $80,362 $4,098,462
Subtotal $9,935,915
Total Treatment and Assessment Costs
Weekly Treaanent and-Assessment ofAR....4SA. ~J92S.onw.ards.. .-.,- ~ .'
. Unit Number--
Unit'cost -..- ... Cost...
TecbniciaDs
Hours
416
$40 .
$16,640
$39,000
Laboratory Analyses
Each
260
$150'
. Subtotal
. SS5,640
Present Value (@5% for 4 yean. 1995-1999)
'$187,902 . .
Total Present. Value Cost (Treatment and Assessment)
$10,123,811
,)
.
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Table 12
Cost Estimate for Alternative #3
Cost Estimate Spn:adsheet
Cost Basis:
Treat HLP LeaclJ~ and drain Heap by August 1995
Treat with CDP and Mothball MRP for seasonal use
MRP Treatment only May through July
. Lower Flows from 1996 onwards
.
..
Total Capital Costs
Unit Number Unit Cost Cost
HLP Lear.hatP. Treatment 1000 Gal. 170,000 S32.18 S5,470,600.
Site Support (51.weeks) Week 51 S80,362 $4,09~,462
Shutdown Pumphouse (1 week) LS 1 S52,144 'S52,144
Shutdown ofMRP (3 weeks) LS 1 S148,277 5148,277
Reroute CDP Effluent to Wightman Fork LS 1 $21,000 $21,000
Vebicles DemobilizatioD LS . 1 S5,000 S5,OOO
Subtotal S9,795,~
. Total Treatment and Assessment Costs
Unit Number Unit Cost Cost
CDP Operation @SOD GPM
MRP Operation during May, Jnne and July
1995-96 .
CDP Treatment cost per week
Site Support .
Startup/Shutdown ofMRP
Treatment Cost per Week'"'
.....
Week
Week
Week
. Week"
52 .
52
. 2.
. 13''''
S108,562
S63,056
.S37,621
.. 537.621-'
. Total Year 2
S5,645,224
53,278,912
S7S,24~
5489,073.. ....
S9,488,451
1996-90 (Cost per year)
CDP Treatment cost per week
Site Support
Startup/Shutdown ofMRP
Treatment Cost per Week
Week
Week
. Week
.. Week
52
52
2
13
579,934
S32.;267
$37~621 .
$37,621
Total Year 3/4/5
$4,156,568
SI,677,884
575,242
$489,073
56,398,767
Net Present Value (@S% for 4 years, 1995-1999)
524,411,683
532,207,166
Total Present Value Cost (Treatment and Assessment)
.
.
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"
Table 13
.
Cost Estimate for Alternative #4
Cost Estimate Spreadsheet
Treat HLP Leachate and drain Heap by' August 1995
Treat with CDP and Shutdown MRP
. Construct or Create Storage Capacity
., Reduced Operation after 1996
Cost Basis:
'"
Total Capital Costs
Unit
.. ". - .-'
HLP Leachate Treatment (48 weeks)
Site Suppon (51 weeks)
Shutdown Pumphouse
~~C~Em~mw~~~~F~
Vehicles Demobilizarion
1000 Gal
Week
LS
LS
LS
Total Treatment and Assessment Costs
Unit
CDP Operation @ 500 GPM
Number
170,000
51
1
1
1
Number
Unit Cost
Cost
S32.18
S80,362
SI48,277
S52,144
$5,000
S5,470,600
$4,098,462
- -, SI48,277
S52,144
$5,000
Subtotal
59,795,483
Unit Cost
Cost
1995-96
Treatment cost per week
Site Suppol1
Week
Week
52
52
$108,562
$63,056
Total Year 1
$5,645,224
53,278,912
$8,924,136
1996-97
Treatment cost per week
Site Suppan '
Week
Week"
35
. 35'"
$79,934
, ,S32,267:"~"
Total Year 2
$2,197,690
$1,129~S
$3,927,035,
1997-98
Treatment cost per week
Site Suppon
Week
Week'
26
,26
$79,934
$32,267
Total Year 3
$2,078,284
S2,917J26
':,', $2,917,226
1998-99
Treatment cost per week' - --, - -.,
Site Suppon
Week
Week
18
18
S79,934
, S32,267
Total Year 4
$1,438,812
S580,806
$2,019,618
)
Net Present Worth (@ 5% 1995-99 Treatment and Assessment Costs)
Subtotal Present Worth Cost (Treatment and Assessment + Capital)
STORAGE CONSTRUcnON
COnstnlcted Storaee at CC\BMD LS 1
Total Present Worth Cost (Treatment and Assessment + CapitaJ) .
.
$1.610.000
$25,614,691
51.610.000
S26,52~691
" ,
.... .
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"
Table 14
. ,
. Cost Estimate for Alternative #5
Cost Estimate Spreadsheet
Cost Basis:
Treat HLP Leachate and drain Heap by August 1995
Shutdown CDP, MRP and CWI'P
Construct a New Water Treamient Plant
Plant sized to treat all AMD Sources
Total Capital Costs -
Unit
Number
Unit Cost
.. -
Cost
HLP Leachate Treatment 1000 Gal. 170,000 S32.18
Site Support (51 weeks) Week 51 S80,362
Shutdown CDP and Pumphouse (4 weeks) LS 1 $208,576
Shutdown;MR.P (3 weeks) LS 1 S148,277
Shutdown CWTP (2 weeks) LS 1 S56,606
ICP Demobilization, LS 1 S6,000
StationarY Filter Press - Demob LS 1 $25,000
Mobile Filter Press - Demob LS 1 $6,000
Vehicles Demobilization LS .1 S5,000
CONSTRUcr NEW WATER TREATMENT PLANT (S3.5 TO 5.0 ~ON)
Construction Costs 'LS 1 S5,000,000
Subtotal
Total Treatment and Assessment Costs
Unit
Number
Unit Cost
Cost
New Treatment Plant Operation Year Around.
. Plant Treatment Rate: High During Spring Runoff, Low ia Wiater
1995-96 - ... . . .
Trealment cost per week Week 52
Site Support Week 52
579,934 ,
$32,267
Total Year 1
.
...
S5,470,600
$4,098,462
$208,576
5148,277
556,606
S6,000
$25,000
56,000
$5,000
S5,000,000
515,024,521
$4,156,568 .
SI,677,884
55,834,452
1996-99 (Cost per year)
Treatment cost per week
Site Support .
..Week ..
Week
.52
52
$59,950 S3,117,400
S32,267 SI,677,884
Total Year 2\3\4 $4,795,284
Net Present Value (@S% (or 4 yean, 1995-1999)
517,136,689 .
. S32,161,210
Total Present Value Cost (Treatment and Assessment)
...... ..... . .'.
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