1 65 South Unio n Boulevard Unio n Tower, Suit e 1000 Lakewood, CO 80228

FINA L STOCKPILED FIN E SLA G FEASIBILIT Y STUD Y

Submitted to U.S. EPA Region VIII

999 18th Street Denver, Colorado 80203

375419

Terranext Project No. 06104809

Prepared For:

Denver & Rio Grande Western Railroad

May 13, 1996

Telephone: 303 914-1700 Facsimile: 303 914-1709 www.terranext.com
TABLE OF CONTENTS

1.0 INTRODUCTION ..................................... . 1-1

1.1 Purpose and Organization of Report ...................... . 1-1

1.2 Organization of Report .............................. . 1-3

1 .3 Site Description ................................... . 1-3

1.3.1 Site History ................................. . 1-3

1.3.2 Climatology ................................ . 1-4

1.3.3 Geology ................................... . 1-5

1.3.4 Ground Water ............................... . 1-6

1.3.5 Surface Water ................................ 1-7

1.3.6 Soil s ..................................... . 1-8

1.3.7 Description of Lead Slag ......................... . 1-8

1.3.8 Description of Individual Slag Piles .................. . 1-9

1.3.8.1 The Arkansas Valley (AV) Slag Pile ......... . 1-9

1.4 Remedial Investigations ............................. . 1-14

1.4.1 Summary of Slag Investigations ................... . 1-14

1.4.1.1 State of Colorado RI - 1986 ............. . 1-15

1.4.1.2 EPA Phase II RI 1989 ................ . 1-15

1.4.1.3 James P. Walsh and Associates Soil s Investigation - (Walsh, 1988) ............ . 1-16

1.4.1.4 Jacobs Engineering Slag Samplin g -(EPA,

1990a) .......................... . 1-17

1.4.1.5 D&RGW Slag Pile Remedial Investigation Activities ........................ . 1-19

1.4.2 Ground Water .............................. . 1-25

1.4.3 Surface Water .............................. . 1-26

1.4.4 Soil s .................................... . 1-26

1.5 Fate and Transport ................................ . 1-26

1.5.1 Release Mechanism 1 - Wind .............................. . 1-27

1.5.2 Release Mechanism 2 - Leaching ................... . 1-29

1.5.3 Release Mechanism 3 - Mixing by Human Activities ....... . 1-30

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TABL E OF CONTENT S (continued )

1.5.4 Release Mechanism 4 - Runof f of Slag .............. . 1-30

1.5.5 Release Mechanism 5 - Direct Contact .............. . 1-31

1.6 Risk Assessment ................................... . 1-31

1.6.1 Commercial/Industrial Risk Assessment ............... 1-31

1 .7 Cultural Resources Survey AV Smelter and Slag Site ........... . 1-32

1.7.1 Site Documentation ............................ . 1-33

1.7.2 Recommendations ............................. . 1-34

1 .8 Applicabl e or Relevant and Appropriate Requirements (ARARs) Evaluatio n ........................................ . 1-36

1.8.1 Overview of ARARs ............................ . 1-36

1.8.2 Summary of ARARs for the Stockpiled Fine Slag ........ 1-38

2 .0 IDENTIFICATION AN D SCREENIN G O F TECHNOLOGIE S ........... 2-

2.1 Remedial Action Objective ............................. . 2-1

2.2 General Response Action s ............................. . 2-1

3 .0 DEVELOPMEN T AN D SCREENIN G O F PRELIMINAR Y REMEDIA L ACTION ALTERNATIVES FOR AL L SLA G PILES (EPA , 1993) ......... 3-1

4 .0 DETAILED ANALYSIS OF ALTERNATIVES FOR D&RGW STOCKPILE D FIN E SLA G .................................. . 4-1

4.1 Introductio n ......................................... 4-1

4.2 Evaluatio n Criteria ................................... . 4-1

4.2.1 Overall Protection of Huma n Health and the Environment ... 4-2

4.2.2 Attainmen t of ARARs ............................ . 4-2

4.2.3 Long-Term Effectivenes s and Permanence ............ . 4-2

4.2.4 Reduction of Toxicity , Mobilit y or Volume .............. . 4-3

4.2.5 Short-Term Effectivenes s ......................... . 4-4

4.2.6 Implementabilit y ................................ . 4-5

4.2.7 Cost ........................................ . 4-5

4.2.8 State Acceptance ............................... . 4-6

4.2.9 Communit y Acceptance .......................... . 4-6

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TABLE OF CONTENTS (continued)

4.3 Individual Analysi s of Alternatives ....................... . 4-6

4.3.1 Alternative 1 - No Action ........................ . 4-6

4.3.1.1 Description ........................ . 4-6

4.3.1.2 Assessment ........................ . 4-6

4.3.2 Alternative 2 - Institutional Controls .................. . 4-9

4.3.2.1 Description ........................ . 4-9

4.3.2.2 Assessment ........................ . 4-9

4.3.3 Alternative 3 - Resource Utilizatio n ................. . 4-11

4.3.3.1 Description ....................... . 4-11

4.3.3.2 Assessment ....................... . 4-12

5 .0 COMPARATIVE ANALYSIS OF ALTERNATIVES ................ . 5-1

6.0 BIBLIOGRAPHY ...................................... . 6-1

APPENDICES

Appendix A Cost Summaries for Alternatives Evaluated Appendix B ARARS Evaluation for Stockpiled Fin e Slag Appendix C Responsiveness Summary

FIGURES

Figure 1-1 Slag Pile Location Map Figure 1-2 Location of Stockpiled Fine Slag Figure 1-3 Human Health and Environment Conceptual Site Model

TABLES

Table 1-1 Potential Chemical Specifi c ARARs for the Stockpiled Fin e Slag Table 3-1 Development and Screening of Preliminary Remedial Alternatives Table 5-1 Grid Comparison Method for Alternatives Analysi s
1 .0 INTRODUCTION

1.1 Purpose and Organization of Report

On December 3, 1991, EPA and the Denver and Rio Grande Western Railroad

(D&RGW) entered into an administrative order on consent (AOC) for the performance

of a Remedial Investigation/Feasibilit y Stud y (RI/FS) on lead slag pile s and

performance of specified studies on one zinc slag pile at the California Gulch

Superfun d Site, Leadville , Colorado. EPA studied the slag pile s as part of other

various investigation s at the Site prior to the AOC. D&RGW performed a Remedial

Investigatio n (Rl) for seven lead slag pile s an d on e zinc slag pil e in 1992 (MK, 1992).

Subsequen t to the Rl , a Site-wide Screenin g Feasibilit y Stud y (SFS) was undertaken

as a join t effort between the potentiall y responsible parties (PRPs) and the U.S. EPA,

a nd was completed in March 1993 (EPA, 1993). The SFS screened a number of

alternatives for all types of slag located within the site based on relative cost,

implementabilit y an d effectiveness . The SFS narrowed the evaluated alternatives

from six to three: no action, institutional controls and resource utilization .

On December 15, 1993, D&RGW and EPA entered into a Consent Decree to perform

t he remainder of the work at the site relative to D&RGW's responsibilities . As a

result of the consent decree, D&RGW is to perform a feasibilit y study for stockpiled

fin e slag. EPA determined that the primary concern was with the stockpiled fin e slag

a nd released the greater than 1/4 inch slag for D&RGW's use. The consent decree

states "EPA's primary concern is the fin e fraction of stockpiled slag, i.e., less than 1/4

inch particle size, as a human health exposure pathway. Remedial alternatives

retained in the SFS and evaluation will involve the results of EPA's baseline risk

assessments. If desired, D&RGW may commence ballas t operations within the site

prior to completion of the feasibilit y study. D&RGW is required to submit to EPA an

operations pla n which wil l be subject to EPA approval prior to initiation of operations."

10 CIR, 1993. In July of 1995, D&RGW submitted to EPA a ballas t operations pla n

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which EPA subsequently approved. D&RGW commenced ballas t operations in

Augus t of 1995 and continued until weather conditions prohibited further work.

Durin g the early part of 1995 a commercial/industrial risk assessment was undertaken

by EPA which resulted in a proposed plan . The risk assessment concluded that an

action level for the one element of concern (lead ) in soils would be approximatel y

7,000 mg/kg. The proposed pla n was sent out for public comment with a closin g date

f or comments of September, 1995. The proposed pla n indicates that a large area of

t he commercial industrial zoned area within the Superfun d Site would carry a noaction designation . Five areas, includin g the soils surroundin g the three D&RGW -

owned slag piles , would not carry a no-action designatio n at thi s time, subject to

further evaluation for health protection of current and future workers.

Thi s Stockpiled Fin e Slag Feasibilit y Stud y (SFSFS) , i s being submitted b y D&RGW

pursuan t to the Consent Decree entered on December 15, 1993. Pursuant to the

Consent Decree, the SFSFS addresses the alternatives evaluation for the stockpiled

fin e slag at the Arkansas Valle y (AV) slag pile within the California Gulch Site in

Leadville , Colorado. Stockpiled fin e slag exists only at the AV slag pile . As part of

a ny future ballas t operation s for slag other than that currently at the AV pile , the

coarse material would be transported to the AV pile prior to sorting. Thus , any future

fin e slag that would be generated in the course of ballas t operation s would be

generated at the AV area where the stockpiled fin e slag currently resides. In

summary, stockpiled fin e slag currently exists only at the AV pile and any future

generation of fin e slag would -also occur at the AV pile. No fin e slag exists or would

be generated at any location other than the AV pile . The total volume of stockpiled,

sorted fin e slag and water-quenched fin e slag is approximatel y 190,000 cubic yards. Thi s SFSFS performs a detailed analysi s of alternatives usin g the retained

alternatives from EPA' s SF S applied to stockpiled fin e slag.

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1.2 Organizatio n of Report

Sectio n 1.0 provides an overview of the purposes of thi s report as well as site history . Section s 2.0 and 3.0 provide a reiteration of the findings of the SFS which narrowed

t he alternatives for all slag from six to three. Section 4.0 provides a detailed analysis

of alternatives for the three retained option s for the stockpiled fin e slag only. Sectio n

5 .0 presents a comparative analysi s of alternatives. Section 6.0 is the Bibliography . Appendix A provides costs for the retained alternatives while Appendi x B provides the

analysi s of applicabl e or relevant and appropriate requirements. Appendi x C provides

a responsiveness summary to comments provided on the Draf t SFSFS.

1 .3 Site Descriptio n

T he followin g descriptio n of the California Gulch Superfun d Site includes a brief

history of the Leadvill e minin g district , a general descriptio n of the physiologi c and

hydrologic properties of the Site , and summary description of stockpiled fin e slag at

t he AV slag pile .

1.3.1 Site Histor y

T he California Gulch Superfun d Site is the result of over 130 years of minin g and

mineral processing activity. It encompasses the town of Leadville , Colorado and

surroundin g areas, and is approximatel y 110 miles southwest of Denver at an

elevatio n of approximatel y 10,000 feet above mean sea level . Silver , gold , copper,

lead, and zinc were mined by undergroun d and placer methods from multipl e

sulfide/carbonat e ore deposit s within the Site . Approximatel y 17 smelter facilitie s are

reported to have operated within the Site. Only a few smal l to moderate-sized minin g

operations now exist and no smelters currently operate within the Site .

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T he principal present day mining-related features in the Leadville area include the

following:

• Tailing s impoundment s

• Slag pile s

• More than two thousand waste rock dumps

• Abandoned mining, milling, and smeltin g facilitie s

• A few active minin g and reprocessing operations

• Min e water drainage tunnel s

T he Yak Tunnel , which drain s into the surface water body known as the California

Gulch , is the main point-source discharge of acidic metal-lade n water in the drainage. Thi s tunnel drain s undergroun d minin g areas with relativel y high concentrations of

sulfid e minerals . In 1983, the California Gulch Superfun d Site was placed on the

EPA' s Nationa l Priorities Lis t because of heavy metals loadin g to the Arkansas River.

Recently , ground-water and surface-water monitorin g programs have been

implemented over the length of the California Gulch. Remedial actions have

commenced at the Oregon Gulch Tailings pil e and associated drainage. Also , the

Y ak Tunne l treatment system has been installed to treat surface water from the

Uppe r California Gulch drainage.

Recently EPA and other PRPs have undertaken restoration activities in Malta Gulch , Starr Ditch area an d alon g the lower California Gulch. Additionally , tailings from the

Colorado Zinc Lead minin g area have been removed and consolidated at the Oregon

Gulch impoundment .

1.3.2 Climatolog y

T he climate of the Leadville area is typical of mountainous areas in central Colorado. T he area has extreme temperature changes from summer to winter and in any TerraNext

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season can have rapid changes of weather caused by storms travellin g primaril y from

west to east through the region. The local topographic features strongl y influenc e

climatic variations .

Average annual precipitatio n i s 12.67 inches (Res-ASARCO , 1991) . July an d Augus t

have the most precipitation , and December and Januar y have the least . Summer

precipitatio n is usuall y associated with convective showers. Annual snowfal l depths

f or mountain s in the area range between 200 and 300 inches. Durin g winter months ,

t he depth of snow on the ground in Leadvill e is commonly six inches. Precipitatio n

occurs sporadically , causing occasional flash floods . The precipitation and weather

cycle give rise to an annual peak runoff , usuall y occurring durin g June .

T he temperature extremes range from 86 F to -30 F, with the average minimum

dail y temperature being 21.9°F. The average frost-free season i s 79 days. Win d i s

predominatel y from the northwest (CDL, 1986a).

1.3.3 Geolog y

T he geolog y of the Leadvill e Minin g district is complex. Bedrock consists of the

Precambrian crystallin e rocks overlain by quartzites , shales , limestones , dolomites ,

and sandstones of the Paleozoic era. Numerous fault s exist at the eastern edge of

t he site, rangin g in width from several feet to hundreds of feet . Thi s faultin g was

importan t to igneous intrusio n and subsequent mineralization . Post-mineralizatio n

faultin g has also been documented (EPA, 1989a).

T he primary mineral s deposited by hydrothermal solution s which intruded quartzite

a nd limestone sediments, were predominantl y sulfide s of iron, zinc, and lead, but also

included copper, silver an d gold. Late-Tertiar y tectonic activity faulted the

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mineralized zones into blocks and exposed them to oxygenated ground waters.

Sulfide mineral s were oxidized, formed sulfuri c acid, an d released metal s into

solution . These solution s were transported to carbonate zones, where precipitatio n

reactions occurred between the mineralized sulfuric acid solution s and the carbonate

rock. This depositio n zone of secondary, or remobilized, metal ores is termed the

oxidized zone. These carbonate ores were the dominan t ore zones in many of the

area' s mines (ERA, 1989a).

T he change in geolog y i s significan t downstream from the Pendery Fault , which i s

often used to demarcate the upper from the lower California Gulch drainage and is

located at the eastern edge of Leadville . Above the Pendery Fault, Precambrian

crystallin e rocks are an upthrus t relative to stratigraphic units of sediment s or

alluvium. Below the Fault, three identifiable geologic units are noted: bedrock, lake

b ed sediments , and high terrace gravels. The thickness of the upper and middl e

stratigraphi c units (gravel s and the lake bed sediments) increases from east to west.

T he upper unit varies in thickness from approximatel y 50 feet near the Pendery Fault

to several hundred feet near the Arkansas River. Placer operation s and mine waste

disposal probabl y altered the surface and near-surface features of the high terrace

gravel s stratigraphi c unit (EPA, 1989a).

1.3.4 Groun d Water

T he complex geolog y in the area has a significan t impact on ground water

movement. Ground water occurs in both bedrock and alluvial systems, and recharge

i s principall y from infiltration of snowmelt an d rainfall . Groun d water migratin g

through the bedrock system east and southeast of Leadvill e discharges directl y to

California Gulch surface waters, into mine workings and the Yak Tunnel , or into

downgradien t bedrock or alluvia l ground water systems (EPA, 1989a). In the lower

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streambed of California Gulch, there is an active interchange between the shallo w

ground-water system and the surface water.

1.3.5 Surfac e Water

T he California Gulch Superfun d Site area encompasses about 15 square miles of

surface water drainage upstream from the confluence of the streambed of California

Gulch with the Arkansas River. The main stem of the California Gulch flow s east to

west, jus t south of Leadville , and drain s water from several smal l tributarie s to the

north and south. The Stra y Horse Gulch/Star r Ditch watershed is the larges t subbasin an d drain s lands extensively affected by minin g operations. Al l tributaries to

t he California Gulch, as well as the upper Gulch drainage itself, are ephemeral

drainages . California Gulch drainage receives flow s from two continuous pointsource discharges: 1) the Yak Tunne l at 1 to 2 cubic feet per second (cfs) and; 2) the

Leadvill e wastewater treatment plan t at approximatel y 1 cfs (ERA, 1989a).

Annual flow s in both the Arkansas River and the California Gulch are normall y

highest in the sprin g durin g snowmelt and lowest in the fall and winter. Local

summer thunderstorms are, however, potentiall y capable of producin g high-intensity ,

short-duration flow s in the gulch. Floodin g potential is high because of the lack of

vegetative cover. Maximum flood condition s in the area are expected in the May- Jun e snowmelt period (EPA, 1989a).

D&RGW has performed work near the California Gulch to minimize the direct contact

of surface-water with the slag piles . In the vicinit y of the Arkansas Valley slag pile ,

clean fill has been bermed alon g the toe of the slag to prevent direct surface water

from contactin g the slag.

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1.3.6 Soil s

T he native soil s of the Leadvill e area occur in the Troutville-Leadvill e association . The y are primaril y deep and well-drained, formed in stony and cobbly glacial

outwash. Soil samples collected durin g a 1986 soil survey were foun d to be sandy

loam and Pierian gravell y sandy loam, (Walsh 1988). The samples became

progressively more cobbly and gravell y with depth. Permeabilit y and water capacity

were estimated as moderate. Values reported for pH were moderately acidic to

neutral in surface layers.

1.3.7 Descriptio n of Lead Slag

Lead slag is a mineralized by-product of smelting, resultin g from the primar y

processin g of lead ore by blas t or reverberatory furnaces for the productio n of metal .

Slag is a hard, dark, relativel y dense vitreous material that generall y exists in a

layered or biocky an d angular state. Withi n the California Gulch Superfun d Site , the

slag is generall y foun d very near the former smelter sites.

T he lead slag at the Site is an iron-rich slag that contains approximatel y 25% iron,

substantial amounts of the element s magnesium, calcium and silicon , as wel l as

traces of residual base metals. In geological terms, the slag at the Site is similar in

appearance to extrusive igneous rock, black to grey in color, very dense, hard (>7 on

Mohs scale) and vitreous, generall y with a metalli c luster.

T he major constituent s of lead slag are iron, silico n and calcium, which sum to over

4 5% of the slag by weight . Of the contaminant s of concern at the California Gulch

Superfun d Site , lead and zinc occur at approximatel y 1% and 4%, respectively , while

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arsenic and cadmium occur at values less than 1000 part s per millio n (ppm) and 20

ppm , respectively .

1.3.8 Descriptio n of Individual Slag Pile s

Figur e 1-1 depict s the known historic location s of lead slag pile s at the California

Gulch Superfun d Site in Leadville , Colorado. The slag pile s were selected for

samplin g based on previous identificatio n by ERA, conformance with the definitio n for

lead slag, and volumes greater than 1,000 cubic yards. Detailed maps and data for

the individua l slag pile s are presented in the Final Report for Lead Slag Remedial

Investigation at the California Gulch Site, Leadville, Colorado (Rl) (MK, 1992). Stockpiled fin e slag currently exists only at the Arkansas Valle y (AV) slag pile .

1.3.8.1 The Arkansas Valle y (AV ) Slag Pile

T he AV pil e is the larges t and westernmost of the three slag pile s owned by D&RGW

in the Leadvill e area. Thi s pil e was generated from slag produced primaril y by the

AV smelter facility, which operated from 1882 to 1960. The AV Smelter operated

longer than the other smelters in the Leadvill e area. It was situated in lower

California Gulch drainage , west of the city limits . Slag pile s were initiall y developed

at the lowest level of the plan t toward the base of the slope . Sometime durin g the

1940s, the molte n slag was discharged with cold water, producin g a fine-grained,

water-quenched slag. Unti l thi s time, the molten slag was poured directl y from

crucibles onto the slag pile , where it was allowed to cool, formin g a welded slag. Reliabl e estimates of slag generated by the AV smelter have not been made. Based

upon aerial photography , the pil e volume in the late 1950s was approximatel y 1.2

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Color Map(s)

T he followin g maps contain color that

does not appear in the scanned images. To view the actual images please

contact the Superfun d Record Center

at (303) 312-6473.
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FIGUR E 1-1 SLA G PIL E LOCATION MA P

DENVE R & RI O GRAND E WESTERN RAILROA D
millio n cubic yards. Today , approximately 423,000 cubic yards of slag remain on the

site. The slag pil e was purchased by D&RGW from ASARCO in 1961 for use as

ballast .

Thi s pile is bounded by Leadville Sewage Treatment Plant property and State

Highwa y 24 to the south, old smelter works to the north, wooded propert y to the west,

a nd other smelter-related wastes and Stringtow n to the east. California Gulch runs

adjacen t to the slag pil e vicinity for approximatel y 1/5 it s length. Through thi s reach,

a berm composed of clean fill has been placed at the toe of the slag pile to prevent

t he slag from coming into direct contact with California Gulch. To construct the berm,

t he slag was excavated away from the drainage. Observations taken after

construction of the berm indicate that surface water contact with the slag pile is no

longer occurring. The berm has relevance to the final remedy in that it prevents

stormwater runof f from the Smelter/slag pile area to the California Gulch. Thi s

remedy is expected to remain in place for the duration of the ballas t sorting activities

at the AV.

The AV pile is actuall y composed of a number of sub-piles. These sub-piles can be

divided into two major types: sorted and unsorted. Unsorted slag refers to that slag

which has not been processed for ballas t purposes. Sorted slag is slag that has

been physicall y separated into size fraction s for the purpose of railroad ballas t

production . Fine slag is sorted slag which is less than 3/8 inch. Furthermore , the

slag can be divided into piles that were cooled by two techniques: air-cooling and, in

later years, water-quenching. The water-quenched slag is a granular material with

particle sizes generall y less than 1/4-inch. The air-cooled slag is a more blocky ,

welded material . The AV pile covers an area of approximatel y 200,000 square yards. T he maximum depth of the pile is approximately 50 feet , but in some areas the depth

is less than one foot.

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In the past , the AV pile has been sorted for productio n of railroad ballast . Railroad

ballas t is a potential future use for the large, blocky AV slag. Ballast-sized slag is

defined as that greater than 3/8 inches and less than 2-1/2 inches in diameter. Material smaller or larger than this size is separated into oversize and fines piles . Therefore , the subpile s of the AV site include sorted fines , water-quenched fines ,

ballast-sized material, oversized material, and unsorted air-cooled slag. The existing

fine s pile s an d fine s potentiall y generated from future ballas t productio n are the focus

of this SFSFS. Figure 1-2 depict s the location of stockpiled fin e slag at the AV Slag Pile . Thi s i s the only location within the California Gulch Superfun d Site with

stockpiled fin e slag. The volume of stockpiled fin e slag is approximately 190,000

cubic yards.

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FIGUR E 1-2 ARKANSA S VALLE Y SLA G PIL E LOCATION O F STOCKPILE D FIN E SLA G

DENVER & RI O GRAND E WESTERN RAILROAD
1.4 Remedial Investigation s

1.4.1 Summary of Slag Investigation s

Several previous investigations within the California Gulch Superfun d Site have

addressed the slag at the three D&RGW-owned piles. Thi s section summarizes the

relevant data and discussions presented in those investigation reports. The notable

conclusions include:

Slag is very dense and hard (>7 on Mohs scale)

T he pH of pulverized slag is slightl y basic and has a high bufferin g

capacity. Therefore , the acid generating potential of the slag is far less

than the neutralization potential of the excess carbonate

Slag leaches to a very limited extent under EPA's Method 1312, the

Synthetic Precipitation Leaching Procedure, and metals concentrations

in the leachate are two to four orders of magnitude lower than the

Toxicity Characteristic thresholds

Concentrations of metals in soils beneath slag piles are below the

concentrations of metals in the slag indicatin g minimal leaching potential

within the range of literature values for naturally occurring soils

Fine-grained slag does not become airborne

T he slag does not present major geotechnical stability concerns

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T he followin g sections summarize the various reports generated by both the EPA and

D&RGW concerning slag pile investigation s at the Site .

1.4.1.1 State of Colorado Rl - 1986

Slag was not considered to be a significan t source of contamination and, therefore,

w as not studied durin g the State Rl (CDL , 1986b). Page 3-18 of the State Rl report

notes that:

"Much of the metal in slag has been oxidized in the smelting process

and is in a relatively stable oxide mineral form. In addition, smelting

results in the encapsulation of much of the metal in refractory sites and

in the formation of silicate minerals. Therefore, although numerous

slag piles occur throughout the study area, they are not expected to be

a major source of hazardous metal contamination."

1.4.1.2 EP A Phase I I RM989

In 1986, the EPA' s contractor, CH2M Hill , sampled surface water, ground water, an d

numerous mine waste piles , and three D&RGW slag pile s (EPA , 1989a). The

objective of the mine waste and slag samplin g was to better characterize the

material s in the California Gulch Superfun d Site . Thi s was the firs t time that the EPA

h ad sampled slag at the site. These data are considered useable only for limited

qualitative purposes because the design and implementation of the study did not

result in collectio n of representative data.

Composite samples were collected from locations on each of the three slag pile s

based upon a grid system or upon a visual approximatio n of the center and

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equidistan t perimeter points . The depth interval which samples were to be collected

w as specified in CH2M Hill's work pla n as zero to six inches below the surface of the

material .

Sample s were analyzed in the field for the metals of concern using a portable X-ray

fluorescence (XRF) analyzer, and analyzed by Contract Laboratory Program (CLP)

(EPA, 1990b) protocol s for metals composition , extraction procedure (EP) toxicity

leaching characteristics, ASTM-modified acid shake extractable metals, and ASTM

water shake extractable metals. The report stated that while mine waste piles

typicall y contain the highest concentrations of arsenic, cadmium, copper, manganese,

a nd lead, slag typicall y contains the highest levels of iron and zinc. Slag was also

shown to contain metals such as manganese, lead, copper, and arsenic. The report

noted that because the slags were generally a solid mass with a low surface area to

volume ratio, they would have more limited solubilit y than other mine wastes.

1.4.1.3 James P. Walsh and Associates Soil s Investigatio n - (Walsh, 1988)

T he stated objectives of this study were to defin e potential action levels for soil, to

determine background metal s content of soils , to delineate the extent of soil

contamination, and to determine sources of soil contamination. Three samples of

slag were collected as part of thi s study: one from the Harriso n Street pile , one from

the La Plata pile , and one from an area west of Leadville. A small and

unrepresentative sample of the less than 2 mm fractio n was extracted with a nitric

acid/perchloric acid solution and analyzed for total lead, cadmium, arsenic, and zinc.

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1.4.1.4 Jacobs Engineering Slag Samplin g -(EPA, 1990a)

In May 1989, Jacobs Engineerin g performed the second samplin g of slag for the

EPA. The purpose of the study was to determine the concentrations of metals in the

three D&RGW slag piles and to evaluate the potential for migration of these metals to

soil, water, or air. Potential hazards to the environment and public health from the

slag in Leadville were evaluated. Most of the data from this study were of good

qualit y and considered useable for the intended purposes. Exception s include: 1) five

samples that were analyzed for EP toxicity that, for reasons discussed below, were

unrepresentative and of questionable quality ; 2) acid-base accounting data that was

conservative and not substantiated by spli t sample results; 3) and some particle size

data that was inadequate to evaluate the percent of respirable-sized slag.

In order to obtain a preliminary evaluation of the variability within the slag piles , four

location s were sampled at each of the followin g piles:

Harrison Street pile

La Plata pile

AV oversized and unprocessed subpile s

AV sorted fines subpile

AV ballast-sized subpile

AV water-quenched fines subpiles

Sample s were collected from the center of individual piles or pile quadrants using

shovels, a backhoe, or a ripper blade and a backhoe. Surface samples (zero to six

inches) were collected at all locations . Subsurfac e samples (from a depth of

approximatel y three feet) were also collected for each pil e except the AV sorted fine s

and ballast-sized subpiles , which were assumed to be homogeneous after sorting.

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Sampl e size was determined according to ASTM D-75 (ASTM, 1987) weight

recommendations, which are based on particle size of the material to be sampled.

Sample s were analyzed for 23 target analyte lis t (TAL) metals according to CLP

(EPA, 1990b) procedures. Total sulfur and neutralization potential were determined

using EPA Methods 3.2.4 and 3.2.3, respectively. Particle size distribution was

determined by both the sieve and hydrometer tests, and adjustin g the hydrometer

readings for the specific gravity of slag, teachability was evaluated with the same

three tests used previously by the EPA:

EP toxicity ASTM-modified acid shake extraction

ASTM water shake extraction

Leachin g tests were performed only on the ballast-sized and the sorted fine s

samples . Sampl e preparatio n deviated from standard procedures in an effort to make

the testing more representative: slag was not ground or pulverized prior to leaching

test extractions.

T he most significan t results for the particle size analysis are the percentages of fin e

material (passin g the 200 mesh sieve) in each pile. For the Harrison Street pile , La

Plata pile , and AV ballast-sized, oversized, and unprocessed subpiles , fines were

present at approximatel y 0.5 weight percent. The AV sorted fine s and the waterquenched fine s subpiles showed 5 and 1.5 weight percent less than 200 mesh

fraction , respectively.

T he result s of the three leachin g tests show that none of the RCRA metal s leached

from slag in concentrations exceeding the RCRA criteria of 100 times the drinkin g

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water standards. Five additional EP toxicity tests were performed by the ERA that

were not specified in the samplin g plan . The tests were run on material passin g the

10-mesh sieve from samples with the highest total metals concentrations from each

pile or subpile that had not been previously tested for teachability . Lead was the only

metal that exceeded the RCRA criteria and this occurred in three of the five samples.

It should be noted that the percent passin g a 10-mesh sieve ranges from <0.5 to 6.0

weight percent for these three samples. Therefore, the 10-mesh fraction tested for

EP toxicity constitutes only a very small portion of the slag and is not representative

of the piles .

These five sample results are considered unrepresentative. In addition , the EP

toxicity test conducted is also very aggressive and unrepresentative of condition s in

t he California Gulch drainage. The EP toxicity test was designed to simulate

situations in which a waste is co-disposed in a municipal landfill and saturated with

organic acid.

Statistical evaluation of the data shows that the slag piles differ in composition, with

the exception of some of the AV subpiles (EPA 1990a). Chemical and particle-size

variabilit y within pile s were not significant , nor were the difference s between surface

a nd subsurface chemistry. Thus , the chemical composition within a pile is similar,

however, the pile s appear to be differen t from each other with the exception of the

subpile s at the AV area.

1.4.1.5 D&RGW Slag Pile Remedial Investigation Activities

T he purpose of the Rl was to characterize the major lead slag pile s as well as the

High School zinc slag pile in sufficien t detail such that their chemical and physical

properties could be evaluated for potential impacts on human health and the

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environment. Rl data were used to assess the viabilit y of five potential release

mechanisms identified in the site conceptual model. These five release mechanisms

included wind, leaching, mixin g by human activities, runof f of particulates , and direct

contact. Direct contact had previously been eliminated by ERA in the Preliminary Health Risk Assessment, Leadvilie , Colorado (ASARCO, 1991) leavin g the four

remaining mechanisms to be evaluated as part of the Rl.

T he investigation consisted of several major tasks, includin g literature and document

review, field investigation and sampling, laboratory testin g and analysis , and data

evaluation and summary. Available literature was reviewed to summarize the

histories of smelter operation s and slag pile developmen t and to assist in identifyin g

potential pile locations and slag usage within the site. Aerial photographs were also

examined to help locate slag pile s and determin e gross changes in volume over time.

Informatio n developed durin g this historical review task was then used to focus the

site reconnaissance task.

Durin g site reconnaissance, former smelter sites were investigated for evidence of

lead slag, other smelter debris or byproducts, general physical properties , and visual

indication s of impact to the surroundin g environment. A field geologis t mapped

structural features of the piles to input for geotechnical stability determinations and

-professiona1~sanrey"crews surveyed thepites to accurately calculate current pile

volumes.

Result s of the historical review and site reconnaissance tasks showed that there are

seven major lead slag pile s and the High School zinc slag pile within the site, many

of which have significantl y decreased in volume due to use of the slag. Several of

the lead pile s have been used for railroad ballast , however, the use of the reason for

t he decrease in the High School zinc slag pile is unknown. Thi s decrease in volume

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is primarily due to the use of slag as railroad ballas t over an approximate 40-year

period. Indication s of environmental impacts from slag, particulate movement from

precipitation runoff , and major stability concerns were not observed.

A ll seven major lead slag piles as well as the High School zinc pile within California

and Evans Gulches were then sampled using either hand tools or heavy equipment.

Sampl e locations and volumes were selected to be representative of the individual

piles . A total of 42 slag samples were collected, which included bulk samples from

t he surface to a depth of 3 feet and bulk samples from older areas of the piles . Thi s

approach was taken in an effort to determine if variability existed within a pile due to

poorly refined early smelting techniques. At the welded La Plata pile , two

undisturbed core samples were also collected. A total of ten subslag samples from

beneath the Harrison Street , La Plata, and Arkansas Valle y pile s were collected. The

purpose of these ten samples was to determine the nature of material beneath the

pile s and whether metals from the piles had impacted the subslag material.

Appropriate quality assurance procedures were adhered to durin g the samplin g

phases, as well as the analytical phase of the work. Each of the samples was

submitted for laboratory compositional and teachability analyses. Material from the

finer grained slag pile and subslag material was also submitted for particle size

testing. A portion of each sample was sent to the Resurrection field laboratory for

incorporation in the Resurrection/ASARCO metals speciation program. Compositional

analyses included total metals, water-soluble anions, and acid-base accounting.

Leachability testing included Synthetic Precipitation Leaching Procedure (EPA Method

1312) and column leach tests, which were intended to simulate, as closely as

possible, in situ conditions.

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Compositional results showed that the slag is an iron magnesium silicate, with

residual base metals. Concentration ranges and means for the four primary metals of

concern collected from fin e slag sample locations at the site are as follows:

Arsenic mean 435 mg/kg-sorted fines , 909 mg/kg water quenched fine s

Cadmium mean 11.9 mg/kg-sorted fines , 16.6 mg/kg water-quenched

fine s

Lead mean 10,800 mg/kg-sorted fines , 9,650 mg/kg water-quenched

fines

Zin c mean 44,000 mg/kg-sorted fines , 73,000 mg/kg water-quenched

fines

T he dominant form of sulfur is non-extractable, and acid generation potential (defined

by the presence of pyritic sulfur) is more than compensated for by the neutralization

potential of excess carbonate.

Based upon a statistical analysi s of total metals composition , all lead slag pile s at the

California Gulch Superfun d Site are similar in composition, except for the AV waterquenched fine s and the La Plata piles .

T wo subslag samples (AVB103 and AVB104) were collected from directly underneath

t he water-quenched fines at the AV pile. Compositional results for the subslag

material showed concentrations of metals of concern to be significantl y lower than

those for the slag material and within the range of literature values for metals

occurring naturall y in soil (MK, 1992-Table 4-15). Subslag samples collected from

under the AV water-quenched fin e slag showed the lowest value for arsenic (5.7

mg/kg) , lead (84.8 mg/kg ) and for zinc(188 mg/kg ) from all subslag samples

collected. As for the slag, the subslag samples collected from beneath the water

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quenched fin e slag at AV exhibited a negative acid-formin g potential . Site specific

background has not yet to be established, however, ranges for metals of concern in

Colorado soils are as follow s arsenic (1.2-24 mg/kg) , lead 15-150 mg/kg ) and zinc

(16-300 mg/kg) , Conner and Shacklette , 1975.

Leachin g analysis , which included both SPLP and column leach studies, showed

minimal leachin g of metals of concern. SPLP results for all elements tested in slag

were below the toxicity characteristic criteria, listed in 40 CFR 261.24. Mean values

for the contaminants of concern were generally two orders of magnitude lower than

these regulatory thresholds . Column leach tests showed similar low level s of

leaching. The column leach tests were conducted for two hundred alternate wet and

d ry cycles of precipitation , simulatin g over eight years of rainfall . It should be noted

that several test design factors make the leachin g results more conservative than

what is expected under normal site conditions. These factors include the following:

T he sulfuric acid/nitric acid lixivian t used contained none of the

carbonates typicall y foun d in natural rainwater and was, therefore, a

more aggressive solution.

The leaching test used equal periods of wet and dry conditions

simulatin g an eight year period of precipitation . In situ condition s would

indicate that the pile s are generally dry the majorit y of the time, although

the testing protocol included equal periods of wet and dry cycles.

Particle size data and site-specific meteorological data were used to determine

whether slag in the fine-grained piles has the ability to become airborne. Threshold

frictio n velocities (the wind speed above which the surface material becomes

airborne) were calculated using the mode of the aggregate size distribution . Win d

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data and the height of the pile s were used to calculate the frictio n velocity. Result s

f or the two fines piles are:

Threshold Friction Velocit y

sorted fines 1.0 m/sec

water-quenched fine s 0.58 m/sec

Friction Velocity 0.55 m/sec

A friction velocity lower than the threshold friction velocity demonstrates that

sustained wind gusts (0.55 m/sec, MK 1992) in Leadville are not fas t enough to

cause wind erosion of the slag piles . As with the leachin g tests, several factors in the

calculation s make the results more conservative than what would be expected at the

Site. These factors include the following:

If values more representative of air flow over rough terrain were used in

the calculations, the friction velocity would have been lower than

estimated. Therefore , there would be a greater margin that would exist

between friction velocity and the threshold friction velocity of both the

sorted and water-quenched fines .

Slag has a greater density than the sand and gravel used to develop the

model EPA emission factors which were used by defaul t in the

calculations.

A ir density, and therefore the lifting force of the wind at the same speed,

is lower in Leadville . Because the EPA model test (EPA, 1988) was

conducted in Illinois at an elevation of approximatel y 1,000 feet above

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sea level , the air density would be greater than in Leadville with an

elevation of 10,000 feet .

Periods of high moisture, snow cover, and frozen ground wil l limi t the

potential for dust emissions.

1.4.2 Groun d Water

A site-wide monitorin g program is in effec t for surface and ground water at the

California Gulch Superfun d Site. Groun d water in the vicinity of the stockpiled fin e

slag has not been fully characterized. As noted above, the subslag material showed

concentrations of metals of concern to be significantl y lower than those for the slag

material and within the range of literature values for metals occurring naturally in

soils. These results suggest that surface water infiltration through the slag pile s does

n ot significantl y impact ground water nor does it impact the soils beneath the slag

piles as evidenced by the results of the soil analyses.

As noted earlier, there is active interchange between ground water and surface water

in lower California Gulch. For that reason, a contaminant transport pathway to

ground water does exist for metal contaminants from any upstream source that

contributes metals loadin g to surface water. Site ground water quality is strongly

influenced by depth, with poorer quality foun d at the shallower depths . Generally , the

highest metal concentrations in ground water are within 25 to 50 feet of the surface

(EPA, 1989a).

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1.4.3 Surface Water

In general, "water quality in the upper Arkansas River is degraded below the

discharge from the Leadvill e Drainage Tunnel , markedl y degraded below California

Gulch drainage, and improved by the clean-water inflow from creeks further

downstream (EPA, 1989a)." The highest metal concentrations occur in the sprin g

durin g snowmelt. Durin g the 1984, 1985, and 1987 investigation s by EPA, primary

drinkin g water standards for cadmium and lead were commonly exceeded, as were

t he Aquatic Water Qualit y Criteria (AWQC) for cadmium, copper, lead, an d zinc (EPA,

1989a). No discreet conveyances of surface water runof f from the AV area have

been noted, additionally , the berm placed along the California Gulch is designed to

eliminate surface water runof f from directl y entering the California Gulch.

1.4.4 Soil s

A significan t portion of the soils in the Leadville/Stringtow n area has elevated heavy

metal concentrations. These concentrations declin e from west to northwest, with

soils closest to tailings , waste rock piles , and former smelter sites containing the

highest concentrations of lead, arsenic, and cadmium (CDL , 1986a). Analysi s of soils

from beneath the fin e slag pile s show the lowest concentration for lead, arsenic and

zinc of any of the subslag samples collected.

1.5 Fate and Transport

T he site conceptual model used in the Slag Pile Rl was developed by EPA and the

Risk Assessment Technical Assistance Committee and presented in the work pla n for

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t he Slag Pile Rl (MK 1991). The human health conceptual site model for slag piles ,

presented in Figur e 1-3, include five potential release mechanisms:

wind

leaching

mixin g by human activities

runof f of slag

direct contact

T he Rl conclusions were applied to each of the primary release mechanisms with the

followin g results:

1.5.1 Release Mechanism 1 - Wind

T he air pathway analysis results indicate that wind erosion is not a significan t release

mechanism in Leadville . Hourly average wind speed data multiplied by the

appropriate factor to determine the maximum sustained wind gust (0.55m/sec) does

n ot meet or exceed the velocity necessary to lift particles off the stationary pile (0.58

m/sec). From this , it may be concluded that wind erosion is not a viable release

mechanism for the lead slag piles , includin g the AV water-quenched and sorted fines

piles .

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HUMAN HEALTH CONCHTTUAL 61T1 MODEL- UBADVlU J

EXPOSURE POTENITAL RELATIVELY LOW

EXPOSURE POTENTIAL RELATIVELY HIGH

PROJ.f 06104809

SCALE : AS SHOWN

FIL E NO . 4809F1-3 DESIGNED BY :

DATE : 1/22/96

PAGE f

DRAWN BY: GSL

APPROVED BY: TerraNext

FIGUR E 1-3 ARKANSA S VALLE Y SLA G PIL E HUMAN HEALTH CONCEPTUA L SIT E MODEL

DENVER & RI O GRAND E WESTERN RAILROA D
1.5.2 Release Mechanism 2 - Leaching

Testin g in subslag material does not indicate that leachate from slag contributes to

elevated metals concentrations in the vadose zone beneath the slag piles . This

conclusion is supported by the lack of acid generating potential and the neutral to

basic pH of the slag and subslag materials. In fact the lowest concentrations for

three metals of concern arsenic, lead and zinc were detected in subslag samples

collected from beneath the AV water-quenched slag.

Leachin g of metals of concern was analyzed durin g two differen t leachin g procedures

(SPLP and column leach). The results indicated that each of the differen t slags

tested had the potential to leach small quantities of metals. Additional considerations

such as soil sorption , evaporation, dilutio n by ground and surface water, and sheet

runof f require further evaluation to fully understand the potential impacts. At the

conclusion of the Rl, leachin g as a potential release mechanism was retained.

Additiona l data collection activities are currently being undertaken under other PRP

work plan s to better defin e the hydrologic system in the vicinity of the major slag pile s

a nd alon g the California Gulch drainage. Key additional data to be evaluated include

t he identification of those portions of the California Gulch stream that are gainin g and

losin g streams; water qualit y data from piezometers, monitor wells , and surface water

sampling; and flow rates durin g the course of the year. Another key consideration is

t he calculatio n of the residual sediment load and the contribution from other sources

(i.e. tailings and soils) to the stream channel.

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1.5.3 Release Mechanism 3 - Mixin g by Huma n Activities

Transport by human activities has occurred, as slag was historicall y used for road

maintenance within the Site by Lake County and the Colorado Department of Transportation . Characteristics of slag on the railroad tracks are represented by the

results for the AV ballast-sized subpile samples. The ballast-sized sample results

show a low potential for leaching (well below toxicity characteristic criteria).

Based upon data collected for the metal speciation program, ERA 1995a, "the

occurrence of slag is significantl y increased in the vicinity of major streets. Thi s is

consistent with the documented historical use of slag for road sanding." Although in

some areas of Leadville , the relative frequency of slag in residential soils

approximates 15% of the lead bearing phases, less than 2% of the relative lead mass

is attributable to slag. "Within residential soils , slag is concentrated most heavily near

the shoulders of major roads and rail lines, it does not contribute significantl y to the

site's lead mass". ERA 1995a.

1.5.4 Release Mechanism 4 - Runof f of Slag

No evidence of transport of slag fines by surface runof f was observed at any of the

pile s examined. Slag does not appear to be transported from pile s onto adjacent

soil s in rivulets or channels. Pile integrity , especiall y for fine s pile s where this is most

critical , appears intact. Thi s potential release mechanism for slag is not a concern at

t he Site.

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1.5.5 Release Mechanism 5 - Direct Contact

Direct contact with the slag piles was considered insignifican t in EPA's Preliminary Baseline Huma n Health Risk Assessment (EPA 1991b). Therefore , it was eliminated

as a release mechanism.

1.6 Risk Assessment

In 1995, EPA completed two parts of the Risk Assessment for the California Gulch

Superfun d Site . These are Part C Evaluation of Recreational, Worker Scenarios

(EPA 1995b), and Part A Risks to Residents from Lead (EPA 1995c).

1.6.1 Commercial/Industrial Risk Assessment

Risk assessments for Recreational and Worker Scenarios from Lead and Arsenic

exposure have been completed (EPA 1995b). The proposed action level for lead in a

commercial/industrial applicatio n is approximatel y 7,000 mg/kg lead. EPA determined

that there are no identified areas within the Superfun d Site which contain arsenic

levels of concern under this scenario. The result of the risk assessment work was a

proposed pla n leadin g to a no-action ROD for areas within the Superfun d Site

currently zoned Commercial/Industrial . The proposed pla n was released for public

comment on Augus t 9, 1995 and public comments were due no later than September

1 2, 1995. The no action proposed pla n specificall y excluded five

commercial/industrial areas because they may have extensive level s of lead that are

a concern for workers. These areas include D&RGW s Harrison , La Plata, and AV

Slag piles .

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T he significanc e of thi s risk assessment and subsequent no-action proposed pla n for

the slag pile areas are important because it sets action levels for remediation of soils

in and around the slag piles . Based upon the results of subslag samplin g conducted

durin g the Rl (MK 1992), the maximum concentrations of lead in all subslag samples

was 794 mg/kg, approximately one order of magnitude below the proposed action

level. Cost estimates for remedial alternatives related to the slag pile s are extremely

sensitive to the finalizatio n of a remedial-action level for soils under and in the vicinity

of the stockpiled fin e slag pile.

1 .7 Cultural Resources Survey AV Smelter and Slag Site

T he objective of the cultural resources survey for the AV smelter and slag site was to

survey all areas that may be impacted visuall y and/or by potential ground disturbin g

activities , an d to compl y with al l applicabl e Federal legislatio n concerning cultural

resources. Federal agencies, includin g the U.S . ERA, are mandated by a number of Federal regulations , statutes and executive orders to inventory, evaluate and assess

cultural resources located on Federal lands , or on private lands that may be impacted

by land-alterin g project s involving Federal fundin g or action. This legislatio n includes

t he National Historic Preservation Act of 1966 (as amended 1980 and 1992). All of

t he cultural resources investigation s conducted for ASARCO and D&RGW for the

Arkansas Valle y Smelter (AV) site, OU3 and 5, meet or exceed the requirements of

t he above-cited legislation .

T wo documents govern the cultural resources requirements to meet Section 106 of

t he National Historic Preservation Act for this project. The firs t document is the

Programmatic Agreement (PA) between the EPA, Colorado State Historic

Preservation Officer (SHPO) an the National Advisory Counci l on Historic

Preservation (amended 7/94). Thi s agreement provides guideline s for an

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identificatio n and evaluation process, assessing the effect s on management of

historic properties , discovery of historic properties durin g actions, involvement of

interested parties, adherence to standards and guidance, and professional

qualifications . In addition , the PA allowed for developmen t of the second document,

an Identificatio n an d Evaluatio n Pla n (ID&E Plan). Thi s document was finalized in

M ay 1994 (Martaran o et al. 1994) and all work for this project was undertaken in

accordance with the ID&E guidelines .

Recently, the SHPO has determined that the AV smelter is individuall y eligible as a

cultural resource and the followin g recommendations regardin g mitigation .

1.7.1 Site Documentation

As part of the cultural resources summary for all former smelter sites, the Arkansas

Valle y smelter and slag pile s were recorded. The Harriso n and La Plata slag pile s

were not surveyed or recorded because no smelter ruins remain from the past

operations .

T he Arkansas Valle y Smelter site consists of two separate Operable Unit s (OU); OU3

contains the AV slag pile , and OU5 contains the smelter remains. For purposes of

cultural resources assessment, it is necessary to examine and evaluate aJH features of

a site. Prior to recording, a site visit was conducted with several local residents

formerly associated with and/or knowledgeable about the site, includin g Mr. Dan

McEckern, Mr. Joe Polagar, and Mr. Orin Deitrich. The purpose of the site visit was

to help identif y the features and technolog y represented at the site by the present

physical remains. In addition , Sanborn Insurance Maps of the site were examined

prior to field documentation. The AV site was surveyed and recorded by FEC

personnel in September, 1995. Two archaeologist s from FEC conducted an intensive

1-33 TerraNext
pedestrian survey of the site and documented the structures and features remaining

on site. Thi s included the completio n of the appropriate Colorado State Historic

Preservation Offic e (SHPO) resource forms , preparation of a site map based on an

existin g CADD map, and photo documentation of existing features and materials. T he slag pil e was photographed and assigned Feature #11. At the completio n of

fieldwork, the permanent Smithsonia n number of 5LK892 was assigned to the AV

Smelter site by SHPO. A complete and detailed cultural resource survey report

documentin g the site recordation is currently in preparation .

1.7.2 Recommendations

To be eligible for listin g in the National Register of Historic Places , a historic property

must be significan t in American history, architecture, archaeology , engineering, or

culture, and must possess integrity evidenced in location, design , materials,

workmanship, feeling, and association and must meet one of the four National

Register criteria:

A. be associated with events that have made a significan t contribution to

the broad patterns of our history; or

B. be associated with the lives of persons significan t in our past; or

C. embody the distinctive characteristics of a type, period, or method of

construction, or that represent the work of a master, or that possess

high artistic values, or that represent a significan t and distinguishabl e

entity whose components may lack individual distinction ; or

1-34 TerraNext
D. have yielded, or may be likely to yield, information importan t in

prehistory or history.

Site 5LK892, the Arkansas Valle y Smelter, is recommended as individuall y eligible for

t he National Register of Historic Places (NRHP) under criteria B and C. Criterion B

requires that a site "be associated with the lives of persons significan t in our past."

T he AV smelter meets criterion B because the successful developmen t of the AV

Smelter was strongly associated with the Guggenheim family , important persons in

Colorado and U.S. History . The AV smelter meets criterion C because it is a site that

"embodies the distinctive characteristics of a type, period or method of construction"

and/or "represents a significan t and distinguishable entity whose components may

lack individual distinction." The AV Smelter was the largest and longes t operatin g

smelter in the Leadville district (1879 to 1961), processed more minerals than any

other smelter, and was a cornerstone of the ASARCO corporation. Although much of

the machinery, equipment and structures have been removed, the site retains

sufficien t integrity overall to convey the importance and magnitude of the site.

Overall, the smeltin g industry in Leadville played an important role in the development

of the region and of the minin g industry in Colorado, and the AV site is the best

remainin g example in the Leadville minin g district . The slag pile , Feature 11, i s

recommended as a contributing feature. Thi s AV smelter is recommended as a

contributin g component of the Leadvill e Histori c Minin g District , 5LK856. A final

determination of the NRHP eligibilit y will be made by EPA in consultation with SHPO. No further work is recommended at this time. The site has been adequately mapped,

photographed and recorded. Assumin g that the AV smelter will be determined

eligible for the NRHP, and a remedial action(s) is selected for the site, an

assessment of effec t is required to consider the result of such action on those

characteristics that make the site eligible . If a remedial action is required for the slag

1-35 TerraNext
pile , that effec t must be assessed as well . Whil e the pil e is not the primary significan t

characteristic of the site, it does contribute to the overall feelin g of the magnitude and

importance of the site. No additional work would be required for a findin g of no

adverse effect . A findin g of an adverse effec t may require some form of mitigation . Mitigatio n requirements would be determined by ERA in consultation with SHPO and

t he Advisory Counci l on Historic Preservation. Mitigatio n of effec t could include the

production of archival quality photographs documenting the existing conditions prior to

remediation , or the placement of interpretive signage for the public.

1 .8 Applicabl e or Relevant and Appropriate Requirements (ARARs)

Evaluation

1.8.1 Overview of ARARs

Section 121(d ) of CERCLA, as amended by SARA, states that any remedial action

selected for a site must, at a minimum, attain a degree of cleanup and control of

releases of hazardous substances which assures protection of human health and the

environment. In addition , at the completion of the remedial action, a level or standard

of control which meets ARARs must be attained for any hazardous substance,

contaminant, or pollutan t that remains onsite.

T he National Contingency Plan (NCP) (see 40 CFR Part 300), establishes the

framework for the identificatio n and applicatio n of federal and state requirements for

remedial actions at CERCLA sites. CERCLA and the NCP also specif y that only

those state cleanup requirements or standards that are both more stringent than the

Federal counterpart and are identified in a timely manner may be "applicable" or

"relevant and appropriate" to the remediation of a CERCLA site.

1-36 Terranext
ARARs are identified as either "applicable" or "relevant and appropriate". The NCP

gives the followin g definition s of "applicable" and "relevant and appropriate"

requirements:

Applicabl e requirements means those cleanup standards ,

standards of control , and other substantive requirements, criteria,

or limitation s promulgated under federal environmental or state

environmental or facilit y sitin g laws that specificall y address a

hazardous substance, pollutan t or contaminant , remedial action,

location, or other circumstance foun d at a CERCLA site.

Relevant and appropriate requirements means those cleanup

standards , standards of control , and other substantive

requirements, criteria, or limitations promulgated under federal

environmental or state environmental or facility sitin g laws that,

while not "applicable" to a hazardous substance, pollutant ,

contaminant, remedial action, location , or other circumstance at a

CERCLA site, address problems or situations sufficientl y similar

to those encountered at the CERCLA site that their use is well

suited to the particular site (see 40 CFR 300.5).

T he relevance and appropriatenes s of a requirement is judged by evaluatin g several

factors, includin g the characteristics of the hazardous substances foun d at the site,

a nd the physical settin g of the site. Only portion s of requirements may be relevant

a nd appropriate for a remedial action; however, any requirement or portion thereof

that is determined to be relevant and appropriate must be complied with to the same

degree as if it were applicable .

1-37 TerraNext
There are three types of ARARs . Chemical-specific ARARs establish health or riskbased concentration limit s for contaminants found in the various environmental media

at the site. Action- specific ARARs establish controls on the remedial activities which

are a part of the remedial solution. Location-specific ARARs set limitation s on

remedial activities as a result of the location of the contamination or the location of

t he activities being considered. Location- specific ARARs can include restrictions for

activities performed in wetlands , flood plains , and historical sites. Guidanc e and

criteria which are not ARARs at the site, but may be useful in developin g CERCLA

remedies are also identified, as appropriate , and evaluated as to-be-considered

(TBC) criteria or guidance.

1.8.2 Summary of ARARs for the Stockpiled Fin e Slag

An ARARs analysi s for the Stockpiled Fine Slag is presented in Appendix B. Tabl e

1-1 presents a summary of the ARARs to be used for performance of the remedial

action from the discussion s presented in Appendi x B. Where necessary, additional

discussion of location- and action-specific ARARs is provided in conjunction with each

of the three retained alternatives.

T he ARARs evaluation concluded that consideration of Best Managemen t Practices

(BMPs) is indicated by the Nonpoin t Source Control Program for all of the retained

alternatives . In addition , BMP-based Best Available Technolog y (BAT) for stormwater

control may be applicabl e to future reuse of the stockpiled fin e slag. Stormwater

control s will be required if the stockpiled fin e slag reuse or reworking results in a

poin t source discharge. At this time there is no evidence of a discernable

conveyance or point-source discharge from the stockpiled fin e slag piles .

1-38 Terranext
Standards , Requirements,

Criteria. Limitation s

Colorado Ground Water Standards

Surface Water:

Colorado Water Quality Standards

TABL E 1-1 POTENTIA L CHEMICA L SPECIFI C ARARs FOR TH E STOCKPILED FINE SLA G

Citatio n

State: 5 CCR 1002-8 §§

3.11.0-3.11.8

State: 5 CCR 1002-8, §§

3.1.0-3.1.17

Description

Establishes a scheme for

identifyin g groundwater

specified areas, for

classificatio n of Colorado

groundwater and provides

numeric standards.

Establishes standards and

classifications for Colorado

surface waters.

Potentially Applicable / Relevant and Appropriate

No/Ye s

Yes/N o

Comment

S ee Appendix B Section 3.2.

S ee Appendix B Section 3.1.1.
TABL E 1-1 (cent.) CHEMICA L SPECIFI C CRITERIA TO-BE-CONSIDERED (TBC ) FOR TH E STOCKPILED FIN E SLA G

Advisories to be Considered and Guidance

Interim Guidance on

Establishin g Soi l Lead Cleanup Levels at Superfun d Site s

Revised Interium Soil Lead Guidance for CERCLA Site s

a nd RCRA Corrective Facilitie s

Citation

EPA Directive #9355.4-02, September 1989.

OSWER Directive #9355.4-12 July 1994.

Description

Establishes guidance cleanup

levels for lead contaminated

soils.

Establishes guidance cleanup

levels for lead contaminated

soils.

To Be Considered

Considered

Considered

Comment

S ee Appendix B Section 3.3.

S ee Appendix B, Section 3.3.
Potentially Applicable or Relevant and Appropriat e

Clean Water Act

National Pollutan t Discharge

Elimination System

TABL E 1-1 (cont.) POTENTIAL ACTION SPECIFI C ARARs FOR THE STOCKPILED FINE SLAG

Citation

40 C.F.R . Parts 122, 125

pursuant to 33 U.S.C . § 1342

State: 5 CCR 1002-2, §§6.1.0

to 6.18.0, pursuant to C.R.S.

25-8-501

Description

Requires permits for the

discharge of pollutant s from

any point source into waters of

t he United State s includin g

stormwater.

Potentially Applicable / Relevant and Appropriate

Yes/N o

Comment

S ee Appendix B Section s 4.1,

4.2 and 4.3.

Clean Air Act

Colorado Air Pollutio n Control Regulation s Fugitive Paniculate

Emissions

State: 5 CCR 1001, Regulation N o. 1, Section lll. DRequires all sources of

particulate emissions to appl y

technically feasible and

economically reasonable

control measures.

Yes/N o Technicall y feasible and

economically reasonable

control measures will be

applied to reuse of the

stockpiled fine slag.
TABL E l-l (cont.) ACTION SPECIFI C CRITERIA TO-BE-CONSIDERED (TBC ) FO R STOCKPILE D FIN E SLA G RETAINE D ALTERNATIVES

Advisories to he Considered and Guidance Citatio n

Clean Water Act Nonpoin t Source Management

E PA Requirements for Water Quality Planning and Management, Nonpoin t Source Management and Control .40 CFR Parts 130, § 130.6(c)(4)

Description

Establishes Best Management Practices as an acceptable CWA section 208 and 303(e) Water Quality Management Plan element for achieving

water quality goals.

To Be Considered

Considered

Comment

T he nonpoint source

management program, with the

regulatory and nonregulatory

applicatio n of Best Management Practices is an

approach states may use in

developing acceptable CWA Section 208 Water Quality Management Plans. BMPs

would only be ARAR for

nonpoint source management

where a state has adopted BMPs as part of a duly

promulgated regulatory

program. Colorado has not

promulgated BMP-based

nonpoint source control

requirements.
TABLE 1-1 (cont.) POTENTIAL LOCATION SPECIFI C ARARs FOR STOCKPILED FINE SLAG

Potentially Applicable or Relevant and Appropriat e Citation Description

Potentially Applicable / To Be Considered Comment

National Historic Preservation Act, Executive Order 11593

16 U.S.C . §470

40 C.F.R . § 6.301(b)

36 C.F.R . Part 800

State: C.R.S. 24-80-101-108

Fish an d Wildlife Coordination Act

16 U.S.C . §§ 661-666

40 C.F.R. § 6.302(g)

E PA must account for the Yes/No

affect s of any action on any

property with historic,

architectural, archeological or

cultural value that is listed or

eligible for listin g on the National Register of Historic Places, or the Colorado Register of Historic Places.

Requires consultation when Yes/No

federal department or agency

proposes or authorizes any

modificatio n of any stream or

other water body to provide for

adequate provision for

protection of fish and wildlif e

resources.

Effect s of the alternatives

retained for consideration on

listed properties wil l be

considered.

Prior to modificatio n of water

bodies appropriate agencies

wil l be considered.
Selected implementatio n of BMPs wil l also ensure attainment of the applicabl e

Colorado Water Quality Basic Standard which requires that "state waters shal l be free

from substances attributable to ... non-point source discharges in amounts,

concentrations or combinations...(a) which can settle to form bottom deposit s

detrimental to the beneficial uses". (See §3.1.11).

Regulatio n 1 of the Colorado Air Pollutio n Control Regulation s requires all sources of

particulate emissions to utilize technicall y feasible and economically reasonable

control measures. Thi s requirement is applicabl e to fugitive emissions, if any,

resultin g from the reuse or reworking of the stockpiled fin e slag.

T he Colorado Stream Standards were foun d applicabl e as the long-term goal for

water qualit y in Segmen t 2b of the Arkansas River.

I n summary:

BMP-based BAT for stormwater control will be applicabl e if future reuse of the

stockpiled fin e slag results in a point source discharge.

Cost effective BMPs pursuant to the non-point source program are to-beconsidered criteria.

Technicall y feasible an d economically reasonable fugitive particulate emission

control measures are applicabl e to future reuse of the stockpiled fin e slag.

Colorado Stream Standards represent the lon g term goal for water quality in

Segment 2b of the Arkansas River.

1-40 Terranext
2 .0 IDENTIFICATION AND SCREENING OF TECHNOLOGIES

2 .1 Remedial Actio n Objective

Based upon the SFS and Consent Decree, the remedial action objective for the

stockpiled fin e slag is to:

Prevent leachin g of metal s of concern in concentrations that would have

an adverse impact on soils , surface or ground water in the vicinity of

t he slag piles .

2.2 General Response Action s

In the SFS, the six General Response Action s (GRAs) identified for the Site as a

whole, were employed to identif y technologies and process options applicable to the

slag:

No Action leaves sources in their existin g condition with no

control or cleanup planned. Thi s general response action serves

as a baseline for comparison but may also be a selected remedial

action for resources that pose no risk to human health or the

environment.

Institutional Control s are legal and physical restrictions to control or

prevent present and future use and access to hazardous substances

remaining on site.

2-1 Terrawext
Containment involves physical measures to prevent and control the

release of or direct exposure to hazardous substances, pollutant s or

contaminants of concern.

Removal, Transport , and Disposal involves a complete or partial

removal of source material followed by transportation and disposal at a

differen t location.

Treatmen t involves physical or chemical measures applied to the source

material s that reduce toxicity , mobility , and/or volume of the

contaminants present.

Resource Utilization involves use or reuse of the source material as a

commercial product which removes the source partiall y or totall y from

t he Site.

2-2 TerraNext
3 .0 DEVELOPMENT AND SCREENING OF PRELIMINAR Y REMEDIAL ACTION

ALTERNATIVES FOR AL L SLAG PILES (EPA, 1993)

T he technologies an d process option s retained in the SFS for al l slag pile s were then

assembled into six preliminar y remedial action alternatives:

Alternative 1 - No Action

Alternative 2 - Institutional Control s

Alternative 3 - Containment

(Surfac e Water Controls/Sourc e Surface Controls/Surfac e Barrier) Alternative 4 - Removal/Transport/Disposal

Alternative 5 - Treatment

Alternative 6 - Resource Utilizatio n

Followin g development , each of the six preliminar y remedial action alternatives were

screened for effectiveness , implementability , and cost, again usin g the criteria defined

in the Screenin g Feasibilit y Stud y The results of that evaluation is presented in Tabl e

3-1. The alternatives retained by the SFS for detailed analysis include:

Alternative 1 - No Action

Alternative 2 - Institutional Control s

Alternative 6 - Resource Utilizatio n (incorporates physical separation from

Alternative 5 - Treatment .

3-1 TerrdNext
Table 3-1. DEVELOPMEN T AN D SCREENIN G O F PRELIMINAR Y REMEDIA L ALTERNATIVE S

REMEDIA L ALTERNATIVES & PRIMAR Y

COMPONENT S

DESCRIPTION OF

PROCESS FINA L DISPOSITIO N EFFECTIVENES S IMPLEMENTABILIT Y COST

1) No action

2) Institutional Control s

No action • Unknown

Combination of one Unknown

or more of the

following: Fencing, Deed Restrictions ,

a nd Use Restrictions , Monitoring, Management Practices

Implementabl e Non e

Conventional procedures Low to moderate,

dependin g on material s

and O&M costs

Retained

Retained

3) Surfac e Water Controls/Sourc e Surface Controls/Surfac e Barrier

4)Removal/Transport/ Disposal

atment

i

Cover pile s with

soil/cla y mixture,

revegetate

Diversion Ditches

Marginal reduction in infiltratio n

Removal of pile s for

consolidation on-site

or on-site repository

Physical separation

of slag

Neutralizatio n

Surfac e water run-on only

importan t at certain piles ,

effectivenes s unknown

Dependin g upon characteristics of

repository and engineering

controls leachin g may not be

minimized

Effectiv e in sizin g particle s

Additio n of lime would not be

effective at neutralizin g slag

because of high intrinsic

neutralizatio n capacity . Increases

volume of material .

Medium, Pile non-uniformity ,

would lead to large quantities

of soil/cla y cover material, Steep slopes would be difficul t

to cover.

Medium, Conventional

technology , diversion ditches

may be difficult due to

surface/groun d water

interaction s

Medium, permittin g land use,

transportation are all problems

associated with

implementabilit y

High , conventional technology

f or sorting slag

Medium cost N ot Retained

Low implementatio n and O&M cost

High Cost

N ot Retained

N ot Retained

Medium Capital and O&M Incorporated into Alternative 6

High Capital an d Medium O &M N ot Retained
Table 3-1. DEVELOPMEN T AN D SCREENIN G O F PRELIMINAR Y REMEDIA L ALTERNATIVE S

REMEDIA L ALTERNATIVES & PRIMAR Y

COMPONENT S

DESCRIPTION OF

PROCESS FINA L DISPOSITIO N EFFECTIVENES S IMPLEMENTABILIT Y COST

6) Resource Utilizatio n -Railroad Ballas t -Additive

material for

construction Undersized material

as additive material in

construction

Sort slag, obtain

greater than 3/8" but

less than 2 1/2" for

rail road ballast .

Source Removal off-sit e or usage

within the site

High , conventional technology

f or ballas t operations for large

blocky slag, and fin e material

used for aggregate in

concrete/asphalt or stand alone

material as road fill, etc.

Low Cost Retained

I
4 .0 DETAILED ANALYSIS OF ALTERNATIVES FOR D&RGW STOCKPILED

FIN E SLA G

4.1 Introductio n

T he three retained alternatives from the SFS have been evaluated in detai l for

stockpiled fin e slag at the AV slag pile. The detailed analysis of alternatives was

conducted using the nine evaluation criteria from the National Contingency Plan

(NCR) :

• Overall protection of human health and the environment

• Compliance with ARARs

• Long-term effectivenes s and permanence

• Reduction of toxicity, mobility or volume

• Short-term effectivenes s

• Implementabilit y

• Cost

• State acceptance

• Community acceptance

4.2 Evaluation Criteria

Each of the three retained alternatives is evaluated against the nine NCR evaluation

criteria described below.

4-1 Terranext
4.2.1 Overall Protection of Huma n Health and the Environment

This threshold evaluation criterion assesses the abilit y of each alternative to

adequatel y protect human health and the environment. The overall assessment of

protection draws on the other evaluation criteria, especiall y long-term effectivenes s

a nd permanence, short-term effectiveness , and compliance with ARARS.

Evaluatio n of overall protectiveness focuses on the manner that site risks are

eliminated, reduced or controlled through treatment, engineering or institutional

controls. This evaluation also considers whether an alternative poses any

unacceptable short-term or cross-media impacts.

4.2.2 Attainmen t of ARARs

T he second threshold criterion evaluates the attainment of applicabl e or relevant and

appropriate requirements (ARARs). As discussed earlier, CERCLA Section 121(d )

requires attainment of Federal and State requirements or justificatio n of waiver. The

evaluation include s chemical, action and location-specific ARARs .

4.2.3 Long-Term Effectivenes s and Permanence

T he three alternatives wil l be assessed for the long-term effectivenes s and

permanence that are afforded by each, alon g with the degree of certainty that the

alternative will prove successful . Factors that are considered include the following :

T he magnitude of residual risk remaining from untreated waste or

treatment residual s remaining at the conclusion of the remedial

activities. The characteristics of the residual s should be

4-2 Terranext
considered to the degree that they remain hazardous, takin g into

account their volume, toxicity , mobilit y and propensit y to

bioaccumulate.

T he adequacy and reliabilit y of controls (i.e., containment

systems and institutional controls) necessary to manage

treatment residuals and untreated waste. Thi s factor focuses in

particular on the uncertainties associated with the assessment of

the potential need to replace the technical components of the

alternative and the potential exposure pathways and risks posed

should the remedial action need replacement.

4.2.4 Reduction of Toxicitv. Mobility or Volume

T he degree to which alternatives emplo y recycling or treatment that reduces toxicity ,

mobilit y or volume of hazardous substances shal l be assessed, includin g how

treatment is used to address the principal threats posed by the Site. Factors that will

be considered include the following, as appropriate:

T he treatment or recycling processes that the alternative employs and

materials they wil l treat.

T he amount of hazardous substances, pollutants , or contaminants that

will be destroyed, treated or recycled.

T he degree of expected reduction in toxicity , mobility , or volume of the

hazardous substance due to treatment or recyclin g and the

identification s of which reductions are occurring.

4-3 TerraNext
T he degree to which the treatment is permanent.

T he type and quantity of residual s that will remain followin g treatment,

considerin g the persistence, toxicity , mobilit y and propensit y for

bioaccumulation of the hazardous substances.

T he degree to which treatment reduces the inherent hazards posed by

a ny principal threats at the Site.

4.2.5 Short-Term Effectivenes s

T he short-term effectivenes s of the alternatives will be assessed considering the

following:

Short-term risks that might be posed to the community durin g

implementatio n of an alternative.

Potential impacts on workers during remedial action and the

effectivenes s and reliabilit y of protective measures.

Potential environmental impacts of the remedial action and the

effectivenes s and reliability of mitigative measures durin g

implementation .

Time until protection is achieved.

4-4 TerraNext
4.2.6 Implementabilit y

T he ease or difficulty of implementin g the alternatives will be assessed by considering

t he followin g types of factors:

Technical feasibility , includin g technical difficulties an d unknowns

associated with the construction and operation of a technology , the

reliability of the technology, the ease of undertaking additional remedial

action, and the ability to monitor the effectivenes s of the remedy.

Administrative feasibility , includin g activities needed to coordinate with

other office s and agencies and the ability and time required to obtain

a ny necessary approval s from other agencies.

Availabilit y of services and materials, including: adequate storage

capacity and services; necessary equipment and specialists; and

prospective technologies .

4.2.7 Cost

T he types of costs that shal l be assessed include the following:

capital costs, includin g both direct and indirect costs;

annual operation and maintenance costs; and

n et present value of capital and O&M costs.

4-5 Terranext
4.2.8 State Acceptance

CDPHE comments, as provided durin g the RI/FS process, shal l be assessed an d

addressed durin g the alternatives analysis.

4.2.9 Community Acceptance

This assessment determines which components of the alternatives interested persons

in the community support , have reservations about, or oppose. Thi s criterion cannot

be evaluated unti l the comments on this FS are received.

4 .3 Individua l Analysi s of Alternatives

4.3.1 Alternative 1 - No Action

4.3.1.1 Description

This alternative leaves the stockpiled fin e slag in place with no remediation ,

engineerin g or institutional controls. There wil l not be any long-term maintenance. However, a site-wide surface and ground water monitoring program will continue until

E RA determines such monitorin g is no longer necessary to ensure that human health

and the environment are protected.

4.3.1.2 Assessment

Protection of human health and environment - No complete human exposure

pathways have been identified. Based upon the chemical compositio n of the slag

a nd soil samplin g conducted beneath the slag, the potential for release of metals in

4-6 TerraNext
leachate from the stockpiled fin e slag is minimal . The stockpiled fin e slag has, at

most, insignifican t non-point source impact on water quality .

T he physical features of the slag pile s have remained relativel y unchanged for many

decades. That fact , combined with the determination that the only potential release

pathway is through leachate, suggest s that the status of the slag is not likel y to

change in the near or lon g term. No action is protective of human health and the

environment.

Attainmen t of ARARs - No Action at the stockpiled fin e slag does not impact

attainmen t of ARARs . Ground water qualit y is a functio n of the active interchange

with surface water degraded by the release of more mobile metal species from the

multitude of other contaminant sources in the vicinity. Similarly, the potential for

minimal non-point source metals loadin g from stockpiled fin e slag leachate would at

most represent an insignifican t loadin g to surface water.

Non-poin t source, BMP to-be-considered criteria have been implemented alon g the

slag piles contacting California Gulch.

Long-term effectivenes s - No Action is an effective long-term alternative. The

only identified release pathway determined to have any potential to contribute to

human or environmental risks is the potential for metal s to leach from the stockpiled

fin e slag. Based upon subslag sampling, metals have not leached and wil l not leach

from the stockpiled fin e slag in concentrations that wil l have an adverse impact on

soils , on surface water or on ground water in the vicinity . Based upon the hardness

of the slag, the lack of acid generating potential and the absence of significan t metals

4-7 Terranext
in soil s beneath the slag, the potential for exposure to metals of concern foun d in the

slag is unlikel y to change in the lon g term. For that reason, no action represents a

reliable alternative.

Reduction of Toxicity , Mobility or Volume - No Action does not further reduce

t he very limited toxicity or mobilit y of metals of concern in the stockpiled fin e slag. In

t he absence of complete exposure pathways , there is no indicatio n that toxicity and

mobilit y of hazardous substances in the slag pose a human health risk. From a land

use perspective, the slag volume is not an issue as tourists come specificall y to

observe historic mining practices. Implementatio n of the No Action alternative,

however, will not reduce the volume of the fin e slag foun d at the site.

Short-term effectivenes s - No Action does not create additional risk to the

Leadvill e community durin g implementation . No workers are involved and no short

term measures require evaluation for reliability .

Implementabilit y - No Action is technicall y feasible as it does not rely on any

technology . As the status quo, no action is implementable .

Cost - No Action is cost effective . There are no costs associated with this

remediation option .

State Acceptance - CDPHE comments, as provided durin g the RI/FS process,

shal l be assessed and addressed durin g thi s alternatives analysis .

Communit y Acceptance - Communit y acceptance will be incorporated at the

close of publi c comment period.

4-8 TerraNext
4.3.2 Alternative 2 - Institutional Control s

4.3.2.1 Description

Institutiona l controls involve restrictin g access or activities that could increase the

potential for leachin g from stockpiled fin e slag. Control s include fencing, land-use

restrictions, and deed restrictions. Additionally, community awareness programs

could be implemented to alert the community to any physical hazards associated with

t he fin e slag. Control s could be implemented separately or in combination.

Coordinatio n with state and local agencies would be required. Periodic monitorin g

may be required to ensure that any restrictions remain in force.

4.3.2.2 Assessment

Protection of human health and environment - Implementatio n of institutional

controls would be protective of human health and the environment. No complete

human exposure pathways have been identified. Based upon the chemical

compositio n of the slag and soil samplin g conducted beneath the stockpiled fin e slag,

t he potential for release of metals in leachate from the stockpiled fin e slag is very

minimal. Relative to the other sources present in the vicinity, the stockpiled fin e slag

has, at most, an insignifican t non-point source impact on water quality .

That fact , combined with the determination that the only potential release pathway is

through leachate, suggests that the status of the slag is not likely to change in the

near or lon g term.

Fencin g would eliminate the smal l potential for direct contact with the stockpiled fin e

slag, but direct contact is not an exposure pathway of concern (EPA, 1991b) .

TerraNext 4-9
Fencin g does not minimize or reduce any potential for the stockpiled fin e slag to

produce leachate.

Attainmen t of ARARs - Implementatio n of institutional controls does not impact

attainment of ARARs . The potential for non-point source metals loadin g to surface

water from stockpiled fin e slag leachate is minimal to nonexistent. The use of

institutional controls on the stockpiled fin e slag will not have any effec t on ground

water quality . Non-poin t source, BMP to-be-considered criteria have been

implemented alon g the slag pile s contacting California Gulch.

Long-Term effectivenes s - Institutional controls can be effective in the lon g

term, but are not permanent. Fencin g requires inspections , maintenance and

community awareness and must be renewed or replaced periodically .

Reduction of Toxicity , Mobility or Volume - Although institutional control s do

n ot further reduce the very limited toxicity or mobilit y of the stockpiled fin e slag, in the

absence of complete exposure pathways, there is no indication that toxicity and

mobility of hazardous substances in the slag pose a human health risk. From a land

use perspective, the slag volume is not an issue as tourists come specificall y to

observe historic minin g practices. Implementatio n of institutional controls will not

reduce the volume of the fin e slag foun d at the Site.

• Short-Term effectivenes s - Institutional controls can be implemented with no

additional risk to the Leadvill e community. Workers and the community can be

adequately and reliabl y protected if fencin g were to be installed.

Implementabilit y - Institutional controls are technicall y feasibl e as reliable

fencin g can be procured and installed readily by available local contractors. Deed

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restrictions have alread y been recorded for the stockpiled fin e slag. Land use

restrictions would require action by either the Lake County Commissioners or the

Leadvill e Town Council . Therefore , because further action is needed by a 3rd party ,

t he potential of implementabilit y of land use restrictions cannot be predicted.

Cost - Most of the cost associated with the institutional controls relates to

fencin g and fence maintenance with some cost attributable to transporting,

consolidating, and fencin g the stockpiled fin e slag material s in a single area.

T he optio n that is considered is to fence and maintain the stockpiled fin e slag located

at the Arkansas Valle y (AV) slag pile .

Fencin g the AV pile would have present value capital and labor costs of $161,000

and inspection and maintenance costs of $8,500 to inspect and maintain over a 30-

year period indicated in the summary in Appendix A.

State Acceptance - CDPHE comments, as provided durin g the RI/FS process,

shal l be assessed and addressed durin g the alternatives analysis .

Community Acceptance - Community acceptance wil l be incorporated at the

close of the publi c comment period.

4.3.3 Alternative 3 - Resource Utilizatio n

4.3.3.1 Description

T he utilizatio n of stockpiled fin e slag as a resource could involve a number of

activities and/or processes. At present, several option s have been identified,

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although it is not possible to ascertain if or when the entire volume of stockpiled fin e

slag would be reused. Options now include: the use of fin e slag as aggregate for

asphalt , aggregate for concrete construction fill, roadbase material, pipe bedding, or

manufacture of concrete block. One of the most features of resource utilizatio n is the

requirement for general widespread acceptance that the material does not and will

not create an environmental concern. To this end, if resource utilizatio n is to be

implementable , the ERA needs to determine which uses of fin e slag are unacceptable

a nd more importantl y which uses are acceptable. The release of thi s material by

E RA for certain specified uses is crucial to both buyer and seller prior to resource

utilization being a viable alternative.

4.3.3.2 Assessment

Protection of human health and environment - As with No Action , human health

and the environment would be protected if stockpiled fin e slag is used as a resource

with appropriate environmental controls. No complete human exposure pathways

have been identified for stockpiled fin e slag in its current condition. Based upon the

chemical composition of the slag and soil samplin g conducted beneath the stockpiled

fin e slag, the potential for release of metals in leachate from the stockpiled fin e slag

is very minimal . Relative to the other sources present in the vicinity , the stockpiled

fin e slag has, at most, an insignifican t non-point source impact on water quality . Over time, any potential impact would be further decreased as the stockpiled fin e

slag is utilized.

Attainmen t of ARARs - As with No Action, resource utilization does not impact

attainment of ARARs. Ground-water quality is a function of the active interchange

with surface water degraded by the release of more mobile metal species from the

multitude of contaminant sources in the vicinity. Similarly, the potential for minimal

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non-point source metals loadin g from stockpiled fin e slag leachate presently

represents at most an insignifican t impact to surface water quality .

T he requirement that fugitive particulate emissions be controlled using technicall y

feasibl e and economicall y reasonable controls can be achieved. Similarly, BMPbased BAT for stormwater control will be applicabl e and attainable if future use of the

stockpiled fin e slag

results in a poin t source discharge. Non-poin t source BMP to-be-considered criteria

have been implemented alon g slag pile s contacting California Gulch stream.

Long-Term effectivenes s - Resource utilizatio n represents a reliable alternative

which uses known technologies , limited only by the regional market demand for the

feedstock. Resource utilization will not have dramatic effec t on the residual risk as

t he pre-resource utilizatio n risks are very limited.

Reduction of Toxicity , Mobilit y or Volume - Over time, reuse could reduce the

very limited potential toxicit y an d potential mobility of the stockpiled fin e slag. In the

absence of complete exposure pathways , there is no indicatio n that toxicity and

mobilit y pose a human health concern. From a land use perspective, the change in

t he total volume of all types of slag will not be significan t if only the stockpiled fin e

slag is utilized.

Short-term effectivenes s - Resource utilizatio n can be implemented with no

additional risk to the Leadville community. Workers and the community can be

adequatel y and reliabl y protected from fugitive particulates and changes in storm

water drainage when the stockpiled fin e slag is utilized.

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Implementabilit y - Resource utilizatio n is technicall y feasible but there are

unknowns as to the marketability of the resource. Demand for the stockpiled fin e

slag wil l be dependant on a number of factors, includin g but not limited to, the level of

construction activity in the vicinity of Leadville.

Cost - Efforts conducted to identif y markets have been unsuccessful to date. Resource utilizatio n does not presentl y appear to be a cost-effective option even if

market demands for the material are identified.

T he option s considered are 1) to process slag for use as a concrete or asphal t

aggregate in construction, and 2) to utilize slag materials for a stand-alone material in

construction, such as a backfil l or pipe bedding.

T he cost effectivenes s of these option s is hindered by the distance the slag material

is located from a major market and the cost associated with sorting the slag. Cost

estimates and a cost summary are included in Appendi x A. Estimates have been

provided for use of the fin e slag for aggregate ($1,120,000 loss after resale) and for

u se in fill material ($244,625 loss after resale).

State Acceptance - CDPHE comments, as provided durin g the RI/FS process,

have been assessed and addressed durin g this alternatives analysis.

Community Acceptance - Community acceptance will be incorporated at the

close of the publi c comment period.

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5 .0 COMPARATIV E ANALYSI S OF ALTERNATIVES

After the alternatives have been described and individuall y assessed against the

criteria, the comparative analysis is used to evaluate the performance of each

alternative in relation to each specific evaluation criterion. Thi s analysi s is performed

qualitatively , in contrast to the precedin g analysis , which analyzed each alternative

independentl y without a consideration of the other alternatives . The purpose of thi s

comparative analysi s is to identify the advantages and disadvantage s of each

alternative relative to one another so that the key tradeoff s can be identified. Tabl e

5-1 provides a grid comparison method to rank the alternatives and their attainment

relative to the followin g criteria.

Protection of Huma n Health and the Environment - All three alternatives are

protective of human health and the environment.

Attainmen t of ARARs - All three alternatives attain ARARs . There is minimal

potential metals loadin g from stockpiled fin e slag and its leachate has an insignifican t

impact on water quality. Resource utilization may marginall y decrease the minimal

metals concentrations in the stockpiled fin e slag leachate because of volume

reduction.

BMP-based BAT for stormwater control will be applicabl e and attainable if the

stockpiled fin e slag utilizatio n results in a poin t source discharge. Similarly ,

technicall y feasible and economicall y reasonable particulate emission controls would

be required for resource utilization .

T he non-point source BMP to-be-considered criterion has been implemented along

slag pile s contactin g California Gulch stream. The need for stormwater controls will

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TABLE 5-1 GRID COMPARISON METHOD FOR ALTERNATIVES ANALYSI S

Criterion

1) Protection of Human Health and Environment

2) Attainment of ARARs

3) Long term

Effectivenes s

4) Reduction of Toxicity , Mobility

or Volume

5) Short term

Effectivenes s

6) Implementability

7) Cost

8) State Acceptance

9) Community Acceptance

Total

Alternative 1 No Action

41

Alternative 2 Institutional Controls

39

Alternative 3 Resource Utilization

5

4

2

5

4

2

5

5

2

5

5

5

5

5

4

5

5

3

3

5

5

36

Notes: Scale of 1-5, where 5 = Highest Attainment

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• Long-Term Effectivenes s - All three alternatives have similar long-term effectiveness. Reuse of the stockpiled fine slag would marginally reduce the residual risk because of volume

reduction. Non e of the alternatives are subject to technology failure from age or wear and tear.

• Reduction of Toxicity , Mobility or Volume - None of the three alternatives reduce the

toxicity and mobility of metals of concern found in the fine slag. However, the toxicity and

mobility of metals in the fines do not pose human health concerns. If reused, the volume of

stockpiled fine slag located in Leadville would be reduced over time.

• Short-Term Effectivenes s - All three alternatives can be implemented in a manner which

protects the Leadville community and the workers implementing the remedy. The No Action

alternative eliminates disturbances of the fine grain slag and requires no workers. Conversely,

resource utilization will create noise, the types of hazards associated with earth-moving

activities, and the potential for fugitive paniculate emissions.

• Implementability - All three alternatives are implementable. Deed restrictions are in

effect . Land use restrictions may not be implementable from an administrative perspective as

they require approval by the Lake County Commissioners. Reuse requires that there be a

commercial market or internal need for the stockpiled fine slag which, at this time, is uncertain.

• Cost - No Action is the most cost-effective approach to meeting the remedial action

objectives and attaining ARARs. There are essentially no costs associated with this remedial

option. The principal cost associated with institutional controls is for fencing materials and

labor. However, the benefits associated with fencing are not directed at the remedial action

objectives. Currently, a no-cost or low-cost use of the stockpiled slag has not been identified

in the vicinity of Leadville. Further work regarding use of fine slag in construction materials

is warranted if this option is to be pursued. Costs for the three options are as follows:

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No Action- Costs $0

Institutional Control s $161,000

Resource Utilization $l,120,000-aggregate; $245,000 fill material

• State Acceptance - CDPHE comments, as provided during the RI/FS process, have been

assessed and addressed during this alternative analysis.

• Community Acceptance - Community acceptance will be incorporated at the close of the

public comment period.

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6 .0 BIBLIOGRAPHY

U.S. District Court for the District of Colorado, 10th CIR, December 1993. State of

Colorado vs. ASARCO, Inc., et.al., Consent Decree with Denver and Rio Grande

Western Railroad.

ASARCO, 1991. Preliminary Health Risk Assessment, Leadville, Colorado, Prepared

by Woodward/Clyde , December 1991.

ASTM, 1987. Standard Practice for Sampling Aggregates, Designatio n D-75-87, Annual Book of ASTM Standards , December 1987.

CDL , 1986a. Leadville/Stringtown Soils Investigation, State of Colorado Department

of Law, Prepared by Engineerin g Science, December 1986.

CDL, 1986b. Yak Tunnel/California Gulch Remedial Investigation, State of Colorado

Department of Law, Prepared by Engineerin g Science, 1986.

EPA, 1995a. Draf t Final Findings of Metal Speciatio n Investigation s at the California

Gulch NPL Site, Prepared by Joh n W. Drexler an d Roy F. Weston , Inc. October 1995.

E PA 1995b. Baseline Huma n Health Risk Assessment for the California Gulch

Superfun d Site - Part C - Evaluation of Recreational and Worker Scenarios prepared

by Roy F. Weston April 17, 1995.

E PA 1995c. Baselin e Huma n Health Risk Assessment for the California Gulch

Superfun d Site - Part A - Risks to Residents from lead prepared by Roy F. Weston , Draf t fina l November 6, 1995.

6-1 TerraNext
ERA, 1993. Sitewide Screenin g Feasibilit y Study , U S ERA Region VII I 1993.

ERA, 1991 a. Administrative Order on Consent for Remedial Investigation/Feasibility

Study (Operable Unit for Slag), CERCLA-92-06, December 1991.

ERA, 1991b. Preliminar y Huma n Health Baseline Risk Assessment for the California

Gulch NPL Site , Leadville , Colorado. Prepared b y Ro y F. Weston , Inc . for U.S. ERA, December 1991.

ERA, 1990a. Data Tabulation Report for Sampling and Analysis of Major Slag Piles -

California Gulch, Leadville, Colorado, U.S. ERA, Prepared by Jacobs Engineerin g Group, Inc. , Februar y 1990.

ERA, 1990b. Contract Laboratory Program Statement of Work for Inorganics Analysis, SOW-4/90.

ERA, 1990c. Interpretive Report for the Sampling and Analysis of the Major Slag Piles - California Gulch, Leadville, Colorado, U.S. ERA, Prepared by Jacobs

Engineerin g Group, Inc. , September, 1990.

ERA, 1989a. Draft Phase II Remedial Investigation Technical Memorandum, 1986-

1987, California Gulch Site, Leadville, Colorado, U.S. EPA, Prepared by CH2M Hill, M ay 1989.

EPA, 1989b. CERCLA Complianc e with other Laws Manual , OSWER Directive

9234.1-01

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ERA, 1988. Compilatio n of Air Pollutan t Emission Factors , Volume 1: Stationar y Point and Area Sources, fourth edition . AP-42. U.S . Environmental Protection

Agency , Research Triangl e Park, North Carolina, 27711. Updat e of Fugitive Dust

Emission Factors in AP-42 Section 11.2 - Win d Erosion, MRI No. 8985-K, Midwes t

Research Institute, Kansas City , Missouri , 1988.

Martorano et. al. 1994. Identificatio n and Evaluation Work Plan , Foothill s Engineering

Consultants , 1994.

Medine, 1994. Conceptual Model and the Development of a Contaminant Transport Model for Metals in California Gulch, Prepared by A.J. Medine , 1994.

MK, 1992. Final Report for Lead Slag Pile Remedial Investigation at the California Gulch Site, Leadville , Colorado, prepared by Morrison Knudse n Corporation for

Denver and Rio Grande Western Railroad Company , December 1992.

MK, 1991 a. Work Plan for Slag Pile Remedial Investigation at California Gulch Site,

Leadville, Colorado, Prepared by Morrison Knudsen Corporation for Denver and Rio

Grande Western Railroad Company , October 1991.

M K, 1991b, Samplin g an d Analysi s Plan for Slag Pile for Slag Pile Remedial

Investigatio n at California Gulck Site , Leadville , Colorado, Prepared by Morrison

Knudse n Corporation Environmental Services Division for Denver & Rio Grand

Western Railroad Company , November 1991.

Res-ASARCO, 1991. Draft Remedial Investigation Scoping Document California Gulch Site, Leadville, Colorado, Prepared by Woodward-Clyde Consultants , April

1991.

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Resurrection, 1992. Final Work Plan - Metal s Speciation and Sources

Characterization at California Gulch CERCLA Site, Leadville , Colorado, Prepared by

Camp, Dresser and McKee , Inc. for Resurrection Minin g Corporation , Januar y 20,

1992.

Walsh, 1988. Draft Soil Investigations in the Leadville Study Area, Lake County,

Colorado. Prepared by James P. Walsh and Associates for Bradley, Campbel l and

Carney, March,

1988.

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APPENDIX A

COST

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ESTIMATES OP COSTS FOR REMEDIAL ALTERNATIVES

OPTION 1

CALIFORNIA GULCH ARKANSAS VALLEY SLAG PILE LEADVILLE, COLORADO

ALTERATIVE:

ITEM:

INSTITUTIONALCONTROLS (I)

FENCE THE AV FINE SLAG PILE

DIRECT CAPITAL COSTS: (Includes Labor, Equipment and Materials, Unless Otherwise Noted)

COSTS COMPONENT

1. Mobilize Materials

2. Office/Storage trailer (8'x30')

3. Earthwork (450 hp bulldozer)

4. Utilities Electric Phone Sanitary Station

5. Fence Materials Fencing Corner Posts Braces Double Swing Gates Locks

TOTAL DIRECT COSTS

UNIT

Lump Lump Cubic Yards

Month Month Month

Lineal Feet Each Each Opening Each

INDIRECT CAPITAL COSTS (% of Direct Capital Costs)

1. Engineering and Design (10% of Capital Costs)

2. Contingency Allowance (20% of Capital Cost)

3. Other Indirects Regulatory License/Permits (5% of Direct Capital Costs)

TOTAL INDIRECT COSTS

PRESENT VALUE OF OPERATION AND MAINTENANCE COSTS Annual inspection and maintenance Year

TOTAL COSTS

ASSUMPTIONS/COMMENTS:

QUANTITY

I

1

5,000

1

1

1

5,300SO

106

3

3

30

UNIT COSTS

$2,700.00

$1,800.00

$2.50

$1,300.00

$600.00

$90.00

$16.00

$95.00

$35.00

$970.00

$15.00

TOTAL CAPITAL COSTS

$2,700

$1,800

$12,500

$1,300

$600

$90

$84,800

$4,750

$3,710

$2,910

$45

$750.00

$115,205

$11,521

$23,041

$5,760

$46,082

$8,443

$163,970

1. Eight (8) loads of fencing materials will be hauled using flatbed trailers.

2. Includes mob & demob, set-up and leveling, tear-down and monthly leasing charge.

3. Earthwork consists of consolidating sorted and water-quenched fine slags before fencing; no mob or demob, onsite contractor

utilized.

4. Fencing is 6 ga. Galvanized wire, 6' high, no barbed wire.

5. Gates are 20' wide and include posts and hardware.
ESTIMATES OP COSTS FOR REMEDIAL ALTERNATIVES

PROJECT: SLAG PILE OPERABLE UNIT LEADVILLE, COLORADO

ALTERATIVE:

ITEM:

RESOURCE UTILIZATION (I)

FINE SLAG ADDITIVE MATERIAL IN CONSTRUCTION (Aggregate for concrete or asphalt, additive to building materials, additive to

grout, concrete and slurry formulations)

DIRECT CAPITAL COSTS: (Includes Labor, Equipment and Materials, Unless Otherwise Noted)

COMPONENT

1. Rescreen material

2. Load and haul

TOTAL DIRECT COSTS

UNIT

Cubic Yards Cubic Yards

INDIRECT CAPITAL COSTS (% of Direct Capital Costs)

1. Engineering and Design (10% of Capital Costs)

2. Contingency Allowance (20% of Capital Cost)

3. Other In directs Regulatory License/Permits (5% of Direct Capital Costs)

TOTAL INDIRECT COSTS

TOTAL COSTS(Direct plus Indirect)

CREDITS FROM SALE OF PRODUCT MATERIAL:

Cubic Yard Cubic Yard

QUANTITY

190,000

190,000

171,000

19,000

COSTS

$5.68

$3.25

TOTAL COSTS

$1,079,200

$617,500

$6.50

$3.10

1. Additive

2. Backfill Material

TOTAL CREDIT

TOTAL COST$/PROFIT($)

ASSUMPTIONS/COMMENTS:

1. AVfute slag pile volumes are used to compute costs.

2. 90% of material \vul be suitable for use as additive.

3. 10% of material used as backfill material.

4. No operations and maintenance costs are necessary over an extended period.

5. Credits from sale of product material have been reduced to reflect transportation costs to a major market.

$1,696,700

$169,670

$339,340

$84,835

$593,845

$2,290,545

$(1,111,500) $(58,900)

$(1,170,400)

$1,120,145
ESTIMATES OP COSTS FOR REMEDIAL ALTERNATIVES

PROJECT: SLAG PILE OPERABLE UNIT LEADVILLE, COLORADO

ALTERATIVE:

ITEM:

RESOURCE UTILIZATION (2)

USED AS STAND ALONE MATERIAL IN CONSTRUCTION (Fill material)

DIRECT CAPITAL COSTS: (Includes Labor, Equipment and Materials, Unless Otherwise Noted)

COMPONENT

1. Load and Haul

UNIT

Cubic Yards

QUANTITY

190,000

CAPITAL COSTS

$3.25

TOTAL DIRECT COSTS

INDIRECT CAPITAL COSTS (% of Direct Capital Costs)

1. Engineering and Design (10% of Capital Costs)

2. Contingency Allowance (20% of Capital Cost)

3. Other Indirect! Regulatory License/Permits (5% of Direct Capital Costs)

TOTAL INDIRECT COSTS

TOTAL COSTS(Direct plus Indirect)

CREDITS FROM SALE OF PRODUCT MATERIAL:

1. Backfill Material Cubic Yard 190,000 $3.10

TOTAL CREDIT TOTAL COST$/PROF1T($)

ASSUMPTIONS/COMMENTS:

1. AV Fine slag volumes are used to compute costs.

2. 100% of material will be suitable for use as backfill.

3. Load and haul is for conveyance to suitable rail loading dock.

4. Credits from sale of product material have been reduced due to transportation costs to a major market.

5. Annual Operations and Maintenance costs are not included in estimate.

TOTAL COSTS

5617,500

$617,500

$61,750

$123,500

$30,875

$216,125

$833,625

($589,000)

($589,000)

$244,625
APPENDIX B

ARARS EVALUATION FOR STOCKPILED FINE SLAG

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TABLE OF CONTENTS

APPENDIX B

1 .0 IDENTIFICATION OF ARARS ............................. . B-l

2 .0 DEFINITION AND CRITERIA FOR EVALUATION OF APPLICABILITY OR RELEVANCE AND APPROPRIATENESS .................... B-2

2.1 Definition of ARARs ............................... . B-2

2.2 Categories of ARARs ............................... . B-4

2.3 Waiver of ARARs ................................. . B-5

3 .0 CHEMICAL-SPECIFIC ARARS AND TBCS ..................... . B-6

3.1 Chemical-Specific ARARs and Guidance to be Considered for Surface Water ......................................... . B-6

3.1.1 Colorado Water Quality Standards (CWQS) ............. . B-6

3.1.1.1 Basic Standards ..................... . B-7

3.1.1.2 Criteria for Stream Classificatio n ........... . B-8

3.1.1.3 Use Attainability Analysi s .............. . B-10

3.1.1.4 Classificatio n of Surface Waters at the California Gulch Site ........................ . B-l l

3.1.1.5 Numeric Water Quality Standards ......... . B-12

3.1.1.6 Antidegradation .................... . B-13

3.1.2 Federal Water Quality Criteria .................... . B-14

3.1.3 Chemical Specifi c Surface Water ARARs for Segment 2b of the Arkansas River .............................. . B-14

3.2 Chemical-Specific ARARs and Guidance To Be Considered for Ground Water ........................................ . B-14

3.2.1 Colorado Groundwater Standards - Identificatio n of Specified Areas and Groundwater Classification s ............... . B-l6

3.2.1.1 Ground Water Specified Areas ........... . B-17

3.2.1.2 Chemical-Specific ARARs for Alluvial Ground Water .......................... . B-19

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TABLE OF CONTENT S (continued)

3.3 Chemical Specific ARARs and Guidance To Be Considered for Soi l . . . B-20

3.4 Chemical-Specific ARARs and Guidance To Be Considered for Air ... B-20

4 .0 ACTION-SPECIFIC ARARS AND TBCS ...................... . B-21

4 .1 National Pollutant Discharge Elimination System, Direct Discharge Requirements ................................... . B-21

4.1.1 Point Source Discharges Related to Stockpiled Slag ........ . B-22

4.1.2 BMPs for Ancillary Industrial Activities Associated with Direct Discharges ................................ . B-23

4.2 NPDES Stormwater Permitting Requirements ................ . B-24

4.3 Colorado Discharge Permit System Regulations .............. . B-26

4.4 Clean Water Act Nonpoint Source Control ................. . B-26

4.5 Clean Water Act Section 404 Dredge and Fill Requirements ........ B-27

4 .6 Colorado Air Pollution Control Regulations for Fugitive Particulate

Emissions ..................................... . B-27

4.7 Colorado Mined Land Reclamation ...................... . B-27

5.0 LOCATION-SPECIFIC AND TO BE CONSIDERED ARARs ........... B-29

5 .1 Fish and Wildlif e Coordination Act ...................... . B-29

5.2 Historic and Cultural Preservation ...................... . B-29

5.3 Endangered Species ............................... . B-30

5.4 Species of Special Concern and Undetermined Status ............ B-30

5.5 Colorado Natural Area Program ........................ . B-31

5.6 Protection of Floodplain s and Wetlands ................... . B-31

5.7 Cultural Resources ................................ . B-31

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APPENDIX B

ARARS EVALUATION FOR STOCKPILED FINE SLAG

1.0 IDENTIFICATION OF ARARS

Section 121(d) of the Comprehensive Environmental Response, Compensation and Liabilit y Act (CERCLA) as amended by the Superfun d Amendments and Reauthorization Act of 1986

(SARA) requires that CERCLA remedial actions comply with federal requirements and those

state requirements that are more stringent than their federal counterparts. The federal or

more stringent state requirements must be either legally applicable or relevant and

appropriate under the circumstances of the release for any hazardous substance or pollutant

that wil l remain onsite at the completion of the remedial activities.

Thi s ARARs evaluation was conducted consistent with the National Contingency Plan (NCP)

and additional interpretive discussions present in the preamble to the proposed rule and the

preamble to the final rule. (See 40 CFR Part 300, Sections 300.400(g), and 300.430(g); 53

FR 51394; and 55 FR 8666 respectively). In addition, the ARARs evaluation employed the

identification methodology provided in the CERCLA Compliance with Other Laws Manual,

Part I, August 8, 1988 and the CERCLA Compliance with Other Laws Manual, Part II, August 9, 1989.

T he scope of this evaluation includes ground water, surface water, air and soil ARARs.

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2 .0 DEFINITION AND CRITERIA FOR EVALUATION OF APPLICABILITY OR

RELEVANCE AND APPROPRIATENES S

2 J. Definition of ARARs

T he NCP defines applicable requirements as:

Those cleanup standards, standards of control, and other substantive

requirements, criteria, or limitations promulgated under federal environmental

or state environmental or facility siting laws that specificall y address a

hazardous substance, pollutant , contaminant, remedial action location or other

circumstance found at a CERCLA site. (See 40 CFR Section 300.5).

T he preamble to the proposed NCP further explains the import of applicability as:

Basically , in determining applicability , the question is whether a regulation

would be legall y enforceable at the site (or for the contaminant or action) if a

private party were remediating the site apart from any CERCLA authority.

(See 53 FR 51436, left column, center).

T he NCP also defines relevant and appropriate as:

Those cleanup standards, standards of control, and other substantive

requirements, criteria, or limitations promulgated under federal environmental

or state environmental or facilit y siting laws that, while not "applicable" to a

hazardous substance, pollutant, contaminant, remedial action, location, or

other circumstance at a CERCLA site, address problems or situations

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sufficientl y similar to those encountered at the CERCLA site that their use is well

suited to the particular site. (See 40 CFR Section 300.5).

The NCP provides eight factors that must be considered, where pertinent, in evaluating

whether a requirement is both sufficientl y similar and well suited. Each of the factors is

more or less pertinent depending on whether the requirement addresses a chemical, location,

or action. The factors include:

• the purpose of the requirement and the purpose of the CERCLA action;

• the medium regulated or affected by the requirement and the medium

contaminated or affected at the CERCLA site;

• the substances regulated by the requirement and the substances found at the

CERCLA site;

• the actions or activities regulated by the requirement and the remedial action

contemplated at the CERCLA site;

• any variances, waivers, or exemptions of the requirements and their

availability for the circumstances at the CERCLA site;

• the type of place regulated and the type of place affected by the release or

CERCLA action;

• the type or size of facility regulated by the requirement;

• any consideration of use or potential use of affected resources in the

requirement and the use or potential use of the affected resource at the

CERCLA site. (See 40 CFR 300.400(g)).

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2.2 Categories of ARARs

ARARs are divided into three categories:

• Chemical Specifi c

• Action Specifi c

• Location Specific

In addition , the NCP has identified a fourth category of information "to be considered",

known as TBCs .

Chemical-specific ARARs include health- or risk-based narrative standards, numerical values,

or methodologies that, when applied to site-specific conditions, establish the acceptable

amount or concentration of a chemical that may remain or can be released to the

environment.

Action specific ARARs are technology or activity-based requirements or limitations on

actions taken with respect to hazardous materials found at CERCLA sites. For example,

RCRA land disposal restrictions may require application of best demonstrated available

technology, or fillin g of wetlands could invoke Clean Water Act requirements.

Location specific ARARs are restrictions placed on the concentration of hazardous substances

or the conduct of activities solely because they occur in specific locations. Examples of

special locations include floodplains , wetlands, historic places , and sensitive ecosystems or

habitats.

TBCs represent Federal and State advisories, criteria or guidance that are not ARARs, but

a re useful in developin g CERCLA remedies. (See 40 CFR 300.430(g)(3)).

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2,3 Waiver of ARARs

Section 121(d ) of SARA and §300.430(f)(l)(C ) of the NCP allow waiver of ARARs where

specific conditions are met:

• the alternative is an interim measure;

• compliance will result in greater risk to human health and the environment;

• compliance is technically impracticable from an engineering perspective;

• the alternative will attain a standard of performance equivalent to that required

by the ARAR;

• the ARAR is a state ARAR which has not been consistently applied; or

• at Superfun d fund-financed sites, attainment of the ARAR does not strike a

balance between protectiveness and the availability of fund monies.

If required, the appropriateness of applyin g a waiver or waivers in relation to the stockpiled

fine slag wil l be full y assessed during remedy selection.

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3 .0 CHEMICAL-SPECIFIC ARARS AND TBCS

T he chemical-specific ARARs and TBCs presented below are grouped on a media specific

basis. The media considered include:

• surface water

• ground water

• surface soils

• air

The universe of chemical-specific ARARs and TBCs reviewed are presented in Appendix B, Tables 1 and 2. Only those standards determined to be potentially applicable or relevant and

appropriate to the alternatives retained for consideration are discussed below.

3.1 Chemical-Specific ARARs and Guidance to be Considered for Surfac e Water

T he followin g potential chemical-specific surface water ARARs were identified and

considered:

• Colorado Water Quality Standards , Classification s and Numeric Standards , Arkansas River Basin, Upper Arkansas River, Region 13

• Federal Water Quality Criteria (FWQC){Primar y and Secondary drinking

water standards and maximum contaminant level goals}

3.1.1 Colorado Water Quality Standards (CWOS)

T he Colorado Water Quality Standards (CWQS) establish basic standards applicable to all

state surface waters; a system for classifyin g state surface waters; procedures and criteria for

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u se attainability analysis; procedures for establishing of numeric water quality standards; and

an antidegradation rule and implementation process. (See 5 CCR 1002-8, Sections 3.1.0

through 3.1.17).

The CWQS are structured to provide broad discretion to the Colorado Water Quality Control

Commission (WQCC ) to craft appropriate numeric standards that reflect naturally impacted

and both reversible and irreversible human-induced impacts to Colorado surface water

quality.

3.1.1.1 Basic Standards

T he basic standards apply to all surface waters in the State of Colorado. The basic standards

mandate that "state waters shall be free from substances attributable to human-caused point

source or non-point source discharges in amounts, concentrations or combinations:

( a) which can settle to form bottom deposit s detrimental to the beneficial

uses.... which include ... mine slurry or tailings, silt , or mud...; or

(b) which form floatin g debris, scum, or other surface material...; or

(c) which produce color, odor, or conditions in such a degree as to create a

nuisance or harm existing beneficial uses...; or

(d) which are harmful to the beneficial uses or toxic to humans, animals,

plant s or aquatic life; or ...

( f) which cause a film on the surface or produce a deposit on shorelines."

(See §3.1.11).

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T he limitations imposed by the basic standards are applicable to the California Gulch stream.

T he basic standards also include limit s on allowable radiation and organic pollutants . Because radioactive constituents or organic pollutant s are not associated with the stockpiled

fin e slag, they wil l not be considered further.

3.1.1.2 Criteria for Stream Classificatio n

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. (See §3.1.6).

For each watershed, the WQCC has the responsibility to assign use classifications and to

review the previously assigned use classification s once every three years as part of a

"triennial review". The numeric water quality standards are subsequently promulgated based

upon the use classification.

To that end, the CWQS employ four broad types of beneficial use to frame the classification

process. The four types of use include:

• recreational

• aquatic life

• agriculture

• domestic water suppl y

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• Recreational Use - The recreational uses are divided into two classifications: 1)

Recreational Use, Clas s 1 - Primary Contact, addresses surface water quality concerns where

ingestion of small quantities of water during the use is likel y to occur; 2) Recreational Use,

Class 2 - Secondary Contact, focuses on streamside activities where ingestion of water is

unlikely to occur. The effec t of the recreation classification on numeric water quality criteria

is limited, the primary consideration being the concentration of fecal coliform bacteria. The

stockpiled fine slag is unlikely to contribute bacterial contamination to the watershed. For

that reason, the recreational use classifications will not be considered further.

• Aquatic Life - Class 1 cold water aquatic life is defined as:

...waters that (1) currently are capable of sustaining a wide variety of cold

water biota, including sensitive species, or (2) could sustain such biota but for

correctable water quality conditions. Waters shall be considered capable of

sustaining such biota where physical habitat, water flow s or levels, and water

quality conditions result in no substantial impairment of the abundance and

diversity of species. (See §3.1.13(l)(c)(i)) .

• Domestic Water Suppl y - Domestic water supply is defined as:

...suitable or intended to become suitable for potable water supplies . After

receiving standard treatment ... these waters will meet Colorado drinking

water regulations... (See §3.1.13(l)(d)) .

• Agricultural Use - Agricultural use is defined as:

...suitable or intended to become suitable for irrigation of crops usually grown

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in Colorado and which are not hazardous as drinking water for livestock... (See

3.1.1.3 Use Attainabilit y Analysi s

The CWQS require that the classification must not jeopardize downstream classifications or

actual uses, and the classifications must be for the highest water quality available. (See

§3.1.6((l)(c ) and (e)). To that end, once evidence has been provided to the Commission and

t he Commission assigns that these surface waters are suitable for aquatic life and full contact

recreation then a required "use attainability analysis" would be conducted whenever the

stream segment in question will not carry either the aquatic life or the full contact recreation

classifications as beneficial uses. (See §3.1.6(3)(a)(ii)) .

Two principal concerns are evaluated as part of a use attainability analysis.

1) (a)ttainability is to be judged by whether or not the use classification can be

attained in approximately twenty (20) years by any recognized control

technique that is environmentally, economically, and socially acceptable as

determined by the Commission after public hearings. (See §3.1.6(l)(e)) .

2) ... uses are deemed attainable if they can be achieved by the imposition of

effluen t limit s under the Federal Act for point sources and cost-effective and

reasonable best management practices for nonpoint source control. (See

In other words, an aquatic life classification is deemed attainable if the use can be achieved,

when the Best Available Technology (BAT) is applied to point source discharges and costeffective Best Management Practices (BMPs) are applied for nonpoint source control. Thi s

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provision will be discussed further in conjunction with the evaluation of nonpoint source

control requirements.

In effect , a findin g of nonattainability acts as a variance, and allows the WQCC to decline to

adopt Table Value Standards (TVS) or ambient-based numeric standards. Instead, a findin g

of nonattainability allows the WQCC to adopt Site-Specific-Criteria-Based numeric standards,

or to not adopt numeric standards for the stream segment in question. Additional discussion

of the types of numeric standards is provided below in section 3.1.1.5.

3.1.1.4 Classificatio n of Surface Waters at the California Gulch Site

T wo principal surface waters are impacted by California Gulch drainage. Segment 6, the

"Mainstream of California Gulch from the source to the confluence with the Arkansas

River", and Segment 2b, the "Mainstem of the Arkansas River from a point immediately

above California Gulch stream to a point immediately above the confluence with Lake

Creek". (See Figure 3-1.)

At the present time, Segment 6, California Gulch stream, is classified for agricultural use,

and recreation class 2, but does not carry either an aquatic life classification or a drinking

water suppl y classification . (See Classificatio n and Numeric Standards for Arkansas River

Basin, 3.2.0, as amended through October 30, 1993).

T he WQCC has declined to assign an aquatic life classification to Segment 6, despite the fact

that the WQCC has not performed a formal use attainability analysis. It should be noted that

the WQCC has used the "equivalent of a use attainability analysis" as the substantive and

procedural basis for not assigning aquatic life classification to other Colorado streams

impacted by mining activities. (See Classificatio n and Numeric Standards for Rio Grande

Basin, 3.6.0, as amended through March 30, 1994, page 40). Regardless, the WQCC

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expressly acknowledged the existing uncontrolled non-point sources of pollutio n when

declining to adopt an aquatic life classification in Segment 6. (See Classificatio n and

Numeric Standards for Arkansas River Basin. 3.2.0, as amended through October 30, 1993,

page 24).

Segment 2b is that reach of the Arkansas River immediately below the confluence with

California Gulch stream. Although Segment 2b is heavily impacted by metals loading from

California Gulch stream, it is classified for Aquatic Life Cold 1 and for Agriculture uses.

The Aquatic Life Cold 1 classification was established as a goal, as evidenced by the

temporary modifications to the TVS. Specifically :

(w)here 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 the use classification may require a temporary modification to the

underlying numeric standard... (See §3.1.6).

Segment 2b was not classified for drinking water supply due to the presence of manganese at

concentrations rendering the water not palatable and the absence of existing use as a domestic

water supply . (See Classification and Numeric Standards for Arkansas River Basin, Section

3.2.0, Statement of Basis and Purpose, Page 10.57).

3.1.1.5 Numeric Water Quality Standards

T he CWQS provides a three-tiered structure for establishing numeric water quality standards.

For unimpacted high quality waters, the WQCC has adopted numeric levels known as the

"Table Value Standards" (TVS) which are presumed to be protective of aquatic life . For

impacted waters where pollutant concentrations exceed TVS values but the beneficial uses are

adequately protected, the WQCC may adopt Ambient Quality-Based Standards. Where

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classified uses are not being protected and a use attainability analysis has found

nonattainability , Site-Specific-Criteria-Based Standards may be developed. Finally,

temporary modification s to numeric standards may also be adopted.

T he TVS are effectivel y equivalent to, and are based upon the Federal Water Quality Criteria

and have been adjusted to protect the beneficial uses of Colorado waters. (See §3.1.7(b)(i)) . It is important to note that many of the TVS promulgated to protect aquatic life from metal

pollutant s are hardness dependent. The TVS are the basis for the promulgated surface water

standards in Segment 2b of the Arkansas River, below California Gulch. The WQCC has

declined to adopt ambient-based standards for Segment 2b.

Temporary modification s to the underlying TVS have been adopted for metal constituents in

Segment 2b. These temporary modifications expire on December 31, 1998. The CWQS s

state a preference for temporary modifications of numerical standards over permanent

downgrading of a classification where the conditions causing the degraded water quality

"may be temporary" in a twenty year time frame. (See §3.1.7(3)) . The TVS in Segment 2b

remain the long term goals for Arkansas River water quality.

T he WQCC has declined to adopt numeric water quality standards (with the exception of

fecal coliform limits) for Segment 6, California Gulch.

3.1.1.6 Antidegrad ati on

The provisions relating to antidegradation are not relevant to current remedial responses

given the presently degraded water quality. All of the stream segments impacted by the

California Gulch Superfun d Site carry a Use-Protected designation and as such are not

governed by the antidegradation review procedures. (See §3.1.8)

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3.1.2 Federal Water Quality Criteria

T he preamble to the proposed NCP states:

( a) State numerical WQS are essentially a site-specific adaptation of a FWQC ,

subject to EPA 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 FWQ C would only be relevant and appropriate in the absence of

current, segment-specific CWQSs . In this circumstance, current, segment specific CWQS s

are available and will be applied as the surface water quality ARARs for the site.

3.1.3 Chemical Specific Surface Water ARARs for Segment 2b of the Arkansas River

T he TVS-based chemical specific ARARs, applicable to Segment 2b of the Arkansas River

for contaminants of concern, are presented in Table 3-1.

3.2 Chemical-Specific ARARs and Guidance To Be Considered for Ground Water

In the preamble to the proposed NCP the EPA recognized that State ground water

classifications may be relevant and appropriate at Superfun d sites:

(t)he classificatio n scheme described above may be superseded by other

classification schemes which may have been promulgated by a State and are

applicable or relevant and appropriate to the CERCLA response. (53 FR

51433 center column, middle , emphasis added).

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TABL E 3-1 CHEMICAL-SPECIFIC ARARS FOR SEGMENT 2b OF THE ARKANSAS RIVER

META L Agriculture

Arsenic, acute

Cadmium, acute

Cadmium, chronic

Copper, acute

Copper, chronic

Iron , chronic

Lead, acute

Lead, chronic

Manganese, chronic

Zinc, acute

Zinc, chronic

N /A

N /A

N /A

N /A

N /A

N /A

N /A

N /A

N/A 3 N /A

N /A

Domestic Water Suppl y

50 ug/l, (1-day) 1

N /A

N /A

N /A

N /A

N /A

N /A

N /A

N /A

N /A

N /A

Cold Water Aquatic Life Clas s 1 (TVS)

N /A

3.9ug/ l dissolved @ 100mg/l hardness2

1 .1 ug/l dissolved @ 100mg/l hardness2

18ug/ l dissolved @ 100mg/ l hardness2

12ug/ l dissolved @ 100mg/l hardness2

1,000ug/l , total recoverable

96ug/ l dissolved @ 100mg/l hardness2

3.9ug/ l dissolved @ 100mg/ l hardness2

1000ug/l , (30-day)

117ug/ l dissolved @ 100mg/ l hardness2

106ug/ l dissolved @ 100mg/l hardness2

'This segment does not carry the Domestic Water Supply Classification . Regardless , when promulgated, the

regulations included this domestic water supply value.

2Based upon an estimate of 100mg/l hardness. (See Final Screening Feasibility Study for Remediation Alternative at the California Gulch NPL Site, Leadville , Colorado, USEPA, September 1993).

'Although this segment does carry an Agricultural classification , and the chronic agricultural manganese

standard is more stringent than the aquatic life standard, the WQCC did not adopt the more stringent

agricultural value.

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T he Colorado Ground Water Standards (CGWS) provide for classificatio n of ground waters

and the adoption of water quality standards to protect existing and potential beneficial uses of

ground waters, the Colorado Interim Narratives Standard (INS) (5 CCR 1002-8, §3.11.2) . Because Colorado has promulgated a scheme for classifyin g groundwater and for assigning

ground water quality standards , both the classificatio n approach and associated ground water

quality standards are relevant and appropriate to ground waters present at the California

Gulch Site.

3.2.1 Colorado Groundwater Standards - Identification of Specified Areas and Groundwater

Classification s

§3.11.4 of the CGWS identifies five classes of groundwaters:

1) Domestic Use - Quality

2) Agricultural Use - Quality

3) Surface Water Protection

4) Potentially Usable - Quality

5) Limited Use and Quality.

These classifications are applied to "specified areas" a concept identified in the definitions at

§3.11.3, and full y developed in §3.11.4(C)(1) :

(w)hen an activity exists or is proposed, the shape, depth, boundaries and

extent of a specified area shall be determined by considering:

a. the presence, extent and nature of existing uses of ground water that

may be affected by the activity , and the reasonably expected future uses

of ground water that may be affected by the activity ; and

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b. the nature and location of the activity and of its discharge; and

c. existing ground-water quality that may be affected by the activity ; and

d. relevant geologic and hydrogeologic conditions, including but not

limited to the presence of ground water hydrologicall y connected to

surface waters and recharge areas.

In addition to §3.11.4(C)(l)(d) , the CGWS further acknowledge the potential for

interconnection between ground water and surface water by providing an the option to

classif y ground water for "Surface Water Protection". The Surface Water Protection

classification is defined as:

A proposed or existing activity does or will impact ground waters such that the

water quality standards of classified surface water bodies within the specified

area will be exceeded. (See §3.11.4(B)(3)).

3.2.1.1 Ground Water Specified Areas

The ground water in the vicinity of the California Gulch stream and its tributaries is complex

and has not been full y characterized. Overall, the geology in the vicinity of the Stockpiled

Fine Slag can be characterized as well drained, cobbled, glacial alluvial deposits . The

uppermost alluvial aquifer is interconnected to a limited extent with ground water contained

within the underlying fractured bedrock, and to a great extent with surface waters in

the area.

It is very common in Colorado for streams and rivers to gain water from ground water

during dry seasons and to lose water to ground water (recharge the groundwater) during

spring runoff and wetter seasons. Because of this, there exists a seasonal zone in the ground

water that extends outward beyond the river banks where the groundwater quality is

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influenced or perhaps controlled by California Gulch stream water quality. The breadth and

seasonal characteristics of that zone of influence is unknown.

There is clear potential for California Gulch surface waters to negatively impact alluvial

groundwater during the various periods and in the various locations where California Gulch

may be a losing stream. (See Conceptual Model and the Development of a Contaminant

Transport Model for Metal s in California Gulch, A.J. Medine, 1/94). Likewise, impacted

alluvial groundwater has the potential to contribute metals loadin g during the periods and at

those locations where California Gulch is a gaining stream.

Based upon the above facts, it is relevant and appropriate to classify ground water in the

vicinity of California Gulch for Surface Water Protection. First, ground water in the vicinity

of the stockpiled fine slag is not used as a source of domestic water and is not likely to serve

as source of domestic water in the future. Domestic water is supplied by the Parkville Water

District. (See §3.11.4(C)(l)(a)) .

Second, the alluvial ground water is hydraulically connected to surface waters and recharge

areas. It is difficul t to distinguish what are the sources of contamination and which media

are receiving the contamination. In fact , the sources and the receiving media may reverse

roles dependent upon the season, weather and other poorly defined attributes of the

hydrologic regime. (See §3.11.4(C)(l)(d ) and Medine, 1/94).

Additionally , the nature and location of the stockpiled fine slag is such that if groundwater

contamination is attributable to leachate, the contaminant contribution from the stockpiled

fin e slag is insignificant in comparison to the influx of metals contamination associated with

surface waters and recharge from other nonpoint sources. (See §3.11.4(C)(l)(b)) .

Also, the existing ground water quality in the vicinity is degraded and unlikely to improve

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significantly given the multitude of other point and nonpoint sources in the vicinity. The

availabilit y of metals from other sources is dramatically higher than the availability of

vitrified metals associated with the slag. (See §3.11.4(C)(l)(c)) .

3.2.1.2 Chemical-Specific ARARs for Alluvial Ground Water

As noted above, it is relevant and appropriate to classify the alluvial groundwater specified

area, located in the vicinity of the Stockpiled Fine Slag, for surface water protection. The

alluvial groundwater impacts, and is impacted by California Gulch and its tributaries.

The WQCC did not believe it was appropriate to classify the surface water in Segment 6 as a

drinking water supply , and did not classify Segment 6 for aquatic life . Although Segment 6

is classified for agricultural use, the WQCC declined to adopt numeric standards for drinking

water use, for aquatic life , or for agricultural use. Absent a significant change in the

contaminant distribution in Stray Horse and California Gulches, there are no facts to

contravene the current classification of Segment 6, or the WQCC's decision to decline to

promulgate numeric standards.

Consistent with the WQCC's surface water classifications, the enormous uncertainties as to

the contribution of various point and nonpoint sources to both groundwater and surface water

contamination make it inappropriate to establish groundwater ARARs derived from

downstream water quality standards. Similarly the inability to attribute contamination

appropriately also dictates against establishment of numerical groundwater ARARs. T he WQCC has acknowledged that much of the contamination in California Gulch is

nonpoint. (See Classificatio n and Numeric Standards for Arkansas River Basin, 3.2.0, as

amended through October 30, 1993, page 24). The Federal and Colorado policies are to

employ BMPs to address nonpoint sources. Further, EPA's findin g that BMPs are BAT for

stormwater permitting strongly suggest that BMPs would be more appropriate than poorly

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understood and poorly justified groundwater or surface water numeric standards. The use of BMPs as ARARs and TBCs will be fully evaluated in Section 4.0.

3.3 Chemical Specific ARARs and Guidance To Be Considered for Soil

Neither federal nor Colorado chemical specific ARARs for soil contamination were identified

f or contaminants of concern for the stockpiled fine slag. A TBC criterion was identified for

soil lead contamination. Specifically , the "Revised Interim Soil Lead Guidance for CERCLA

Sites and RCRA Corrective Action Facilities," July 14, 1994 (Directive #9355.4-12) will be

considered.

3.4 Chemical-Specific ARARs and Guidance To Be Considered for Air

Federal and state ARARs were identified for construction and generation of particulate matter

(PM10) at the site. An emission permit will be required if temporary construction activities

exceed more than two years (See 5 CCR 1001, §3(I)(B)(3)(e)). Control measures to

minimize dust and air monitoring will be implemented, if necessary, during remedial

construction activities.

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4 .0 ACTION-SPECIFIC ARARS AND TBCS

As noted above, action specific ARARs are triggered by specific activities or the application

of specific technologies to site conditions. Those action specific ARARs reviewed and

determined neither applicable nor relevant and appropriate are presented in Appendix B,

Table 3.

T he potentially applicable or relevant and appropriate action-specific requirements identified

f or the retained alternatives for the stockpiled fine slag include:

• Clean Water Act, National Pollution Discharge Elimination System (NPDES), Direct Discharge Requirements

• NPDES Stormwater Permitting Requirements

• Colorado Discharge Permit System Regulations

• Clean Water Act Nonpoint Source Management and Control

• Clean Water Act Section 404 Dredge and Fill Requirements

• Colorado Air Pollution Control Regulations for Fugitive Paniculate Emissions

4.1 National Pollutant Discharge Elimination System, Direct Discharge Requirements

T he Clean Water Act National Pollutant Discharge Elimination System (NPDES) governs the

discharge of pollutants , from any point source, into the waters of the United States . (See 40

C FR §122.1(b)). Application of Best Available Technology Economically Achievable (BAT)

to the point source discharge of toxic pollutant s is required. BAT criteria, also known as

categorical standards, have been developed for direct discharges from specific industrial

categories. Where categorical standards have not been established, case-by-case technology

determinations are based upon best professional judgment (BPJ). (See 40 CFR §125.3). In

addition to categorical standards, best management practices can be required on a case by

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case basis for ancillary industrial activities at facilities with direct discharge NPDES permits.

(See40CF R §125.103(b)).

4.1.1 Point Source Discharges Related to Stockpiled Slag

Categorical standards have not been promulgated for slag reuse. In addition, the

applicability or relevance of technology-based BAT or BPJ criteria requires, at a minimum, a

polluted discharge from a point source. Without polluted water from a point source, BAT

water treatment technologies could not be found applicable. Similarly , BAT water treatment

technologies cannot be found relevant in the absence of a point source discharge, especially

in light of the clear Nonpoint Source Control dictate for application of BMPs to nonpoint

source control. (See the discussion of Nonpoint Source Control at section 4.4).

"Point source" is defined as:

... any discernible, confined and discrete conveyance, including but not limited

to, any pipe, ditch, channel, tunnel, conduit, well, discrete fissure, container,

rolling stock..... (See 40 CFR §122.2)).

Court cases have further interpreted the term point source. In the preamble to the NPDES

Applicatio n Regulations for Storm Water Discharges, 55 FR 47990, November 16, 1990,

E PA cited language from a decision to clarify it's position:

"Simple erosion over the material surface, resulting in the discharge of water

and other materials into navigable waters, does not constitute a point source

discharge, absent some effort to change the surface, to direct the water flo w or

otherwise impede its progress.... Gravity flow , resulting in a discharge into a

navigable body of water, may be part of a point source discharge if the

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(discharger) at least initially collect or channeled the water and other materials. A point source of pollutio n may also be present where (dischargers) design

spoil pile s from discarded overburden such that during periods of precipitation ,

erosion of spoil pile walls results in discharges into a navigable body of water

by means of ditches, gullies and similar conveyances. (Emphasis added).

Discernible, confined, and discrete conveyances that result in discharges to water of the

United States are not found in association with the slag piles . First, the slag piles have

enormous porosity and the slag itsel f has an extremely high density. As a result precipitation

quickly infiltrates and does not obtain sufficient force or momentum to create discrete

conveyances.

Second, the underlying cobbled, glacial alluvial deposit s are porous and any infiltration to the

slag piles is quickly exchanged into the underlying glacial alluvium.

Third, the current location where sorting and reuse occurs is high on a relatively flat hilltop. The location and construction of the access roads and railroad tracks at that location are

configured without discernable conveyances. It is conceivable that future locations for slag

sorting and reuse could result in discernible conveyances and point source discharges.

Regardless, point source discharges are not currently occurring.

4.1.2 BMPs for Ancillar y Industrial Activities Associated with Direct Discharges

T he direct discharge BMPs for ancillary industrial activities are similar to the Stormwater

Permit Requirements in their purpose, their coverage, and their imposition of BMPs. Regardless , the optional direct discharge BMPs could not be applicable in the absence of a

point source discharge and are not relevant and appropriate to the slag piles for the same

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reasons that EPA determined it is inappropriate to include stormwater infiltration in the

definitio n of storm water. (See the discussion of Stormwater Permit Requirements, below).

4.2 NPDES Stormwater Permitting Requirements

Section 405 of the Water Quality Act of 1987 requires that storm water discharges associated

with industrial activity be controlled with using the Best Available Control Technology

(BAT) .

Storm water is defined in the NPDES program as "storm water runoff , surface runoff , snow

melt runoff , and surface runoff and drainage". (See 40 CFR §122.26(b)(13)). Industrial

activity is also broadly defined and includes materials handling and processing areas and rail

lines and access roads used or traveled by carriers of raw materials, manufactured products,

waste material or by-products used or created by the facility. (See 40 CFR §122.26(b)(14)).

T he stormwater requirements only appl y to point source discharges:

"EPA need clarify in this rule making only that a storm water discharge

subject to NPDES regulation does not include storm water that enters the

waters of the United States via means other than a point source". (See 55 FR

47996).

EPA has specificall y concluded that it is inappropriate to address groundwater infiltration

caused by stormwater through the point source, BAT-technology based requirements:

" In today's rule, the definition of storm water excludes infiltration since

pollutants in these flow s will depend on a large number of factors, including

interactions with soil and past land use practices at a given site". (Se e 55 FR 47996).

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As discussed earlier, point discharges have not been identified in association with the slag or

current slag reuse activities. The complex, ill defined interaction of nonpoint sources,

surface waters, and stormwater infiltration associated with the slag piles are the factors that

convinced EPA to remove infiltration from the stormwater permitting program.

If the reuse activities are relocated in the future, it is possible that point source discharges

could occur. In that circumstance, the stormwater permit requirements would be applicable

to the newly created point sources created by relocating the reuse activities. In that instance,

the rules require application of BAT to that discharge. EPA has enumerated its rationale and

approach to stormwater permitting the preamble to the Fact Sheet For Multi-Sector

Stormwater General Permits, at 58 FR 61146:

"For other discharges covered by the permit, the proposed permit conditions

reflect EPA's decision to select a number of best management practices and

traditional storm water management practices which prevent pollution in storm

water discharges as the BAT/BCT level of control for the majority of storm

water discharges covered by this permit. The proposed permit conditions

applicable to these discharges are not numeric effluen t limitations, but rather

a re flexible requirements for developing and implementing site specific plans

to minimize and control pollutant s in storm water discharges associated with

industrial activity. Thi s approach is consistent with the approach used in the

baseline general permits.... (See 58 FR 61146).

B-25 Terranext
4.3 Colorado Discharge Permit System Regulations

T he Colorado Discharge Permit System Regulations (CDPSR) are by definition , "designed to

be in conformity, with that act and the Federal Clean Water Act". (See Code of Colorado

Regulations, Title 5, Article 2, Section 6.2.0, as amended). Because the CDPSR are not

more stringent that their Federal counterpart, the CDPSR will not be considered further.

4.4 Clean Water Act Nonpoint Source Control

The impact of nonpoint source pollution in California Gulch stream is widely recognized.

When assigning use classifications to California Gulch stream the WQCC acknowledged the

existence of non-point sources. Similarly Medine, 1994, also recognized the widespread

existence of non-point sources (called "diffuse sources") in California Gulch stream.

EPA has required, as a pan of its nonpoint source management and control program, that

state Water Quality Management Plans include regulatory and nonregulatory programs and

BMPs. (See 40 CFR §130.6(b)(4)(i)) . Because the program and application of BMPs are

elective to the states, the nonpoint program is not a potential ARAR. Regardless, as a matter

of EPA policy, consideration of BMPs as a means to control nonpoint sources in California

Gulch stream is indicated.

There are two promulgated Colorado regulations the address nonpoint sources of pollution. First , the Colorado Basic Standard require that "state waters shall be free from substances

attributable to ... non-point source discharges in amounts, concentrations or

combinations...(a) which can settle to form bottom deposits detrimental to the beneficial

uses...." (See §3.1.11) . Thi s general prohibition is an applicable requirement, mandating

measures to prevent the nonpoint deposition of deleterious substances in streams.

B-26 Terranext
Second, as noted earlier, the WQCC may not perform a use attainability analysis and find

nonattainability unless BAT is applied to all point source discharges, and unless BMPs are

implemented for all nonpoint source discharges. Although this provision can function as a

variance from the Colorado TVS, it is not an ARAR.

4.5 Clean Water Act Section 404 Dredge and Fill Requirements

Section 404 of the Clean Water Act regulates the discharge of dredged or fill material to the

waters of the United States. It states that no discharge of dredged or fill material shall be

permitted if there is a practicable alternative to the proposed discharge that does not have

other significant adverse environmental effects . "Practicable" is defined by the regulation to

mean available and capable of being done after taking into consideration cost, existing

technology, and logistics in light of overall project purposes. The clean water act is not

retained as an ARAR because no dredge or fillin g of the waters of the United States is

considered for the retained alternatives.

4 .6 Colorado Air Pollution Control Regulations for Fugitive Particulate Emissions

Regulation 1 of the Colorado Air Pollution Control Regulations requires all sources of

paniculate emissions to utilize technically feasible and economically reasonable control

measures. The requirement to utilize technically feasible and economically reasonable

control measures is applicable to future reuse of the stockpiled fine slag.

4.7 Colorado Mined Land Reclamation

The Colorado Mined Land Reclamation (MLR) regulations at 2CCR 407-1 require the

reclamation of mined areas. The MLR details requirements for reclamation measures and

reclamation performance standards in §3.1.5 (Remediation Measures-Materials Handling) ,

B-27 TerrciNext
3.1.9 (Top soiling) and 3.1.10 (Revegatation). The MLR is not considered applicable

because no mining and related reclamation activities wil l occur at the site.

B-28 TerrdNext
5.0 LOCATION-SPECIFIC AND TO BE CONSIDERED ARARs

Location-specific ARARs are restrictions placed on the conduct of activities solely because

they occur in specific locations. The potentially applicable or relevant and appropriate

location specific requirements identified for stockpiled fine slag included:

• Fish and Wildlife Coordination Act

• Historic and Cultural Preservation

• Threatened and Endangered Species

• Species of Special Concern and Undetermined Status

• Colorado Natural Areas Program

• Protection of Floodplain s and Wetlands

5 .1 Fish and Wildlife Coordination Act

T he Fish and Wildlif e Coordination Act serves to protect fish and wildlife when federal

actions result in the control or structural modification to natural streams or water bodies.

Federal agencies must develop measures to prevent, mitigate or compensate for projectrelated losses of fish and wildlife . Specificall y included are project s involving stream

relocation and water diversion structures. If appropriate, prior to modification of water

bodies, the appropriate agencies will be consulted.

5.2 Historic and Cultural Preservation

T he National Historic Preservation Act (NHPA) requires federal agencies to account for the

effect s of any federally assisted undertaking on districts, sites, buildings, structures or objects

that are included on the National Register of Historic Places. Executive Order 11593 also

requires consideration of the cultural environment. Similarly , the Colorado Register of

B-29 TerraNext
Historic Places establishes requirements for protection of properties of state historical

interest. In addition, the Historic and Archeological Data Preservation Act of 1974

establishes procedures to preserve historical and archeological data which might be destroyed

through alteration of terrain as a result of federal construction projects. Impacts on historic,

cultural and archeological resources will be considered.

5.3 Endangered Species

T he 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. Potential impacts to threatened or endangered species and critical habitat will be

considered. The alternatives retained for consideration will not jeopardize the continued

existence of any threatened or endangered species or destroying or adversely modif y critical

habitat.

5.4 Species of Special Concern and Undetermined Status

Under Colorado Law (or policy), the Colorado Department of Natural Resources (CDNR)

has established two designations to protect wildlife species. These two designations are

"species of special concern" and "species of undetermined status". Species of special

concern are defined as native species or subspecies which have been threatened or

endangered or could become threatened or endangered due to low population levels. Species

of undetermined status are species about which too little is known to accurately determine

their status in the state. Colorado's Division of Wildlife maintains a list of species which

have been determined to fit these categories. If species of special concern or of

undetermined status are found at the site and removal activities could potentially impact those

species (or their habitats), the Division of Wildlife's Directive E-l, 1985 (modified) , should

be taken into consideration and coordination with the Division implemented. These internal

B-30 Terranext
designations would be potential To Be Considered (TBCs) for this removal action only if

species in either category are found near the AV slag pile.

5.5 Colorado Natural Area Program

T he Colorado Natural Areas Program maintains a list of Plant Species of Special Concern to

the State of Colorado. It is not authorized by statute and is considered a planning and

management tool. If removal activities impact plant species maintained on the list , the

program is a To Be Considered (TBC) and coordination with the Colorado Division of Parks

and Outdoor Recreation may be required.

5.6 Protection of Floodplain s and Wetlands

Executive Order No. 11988 and Executive Order No. 11990 require federal agencies to

evaluate the potential adverse effect s of proposed actions on Floodplain s and Wetlands ,

respectively. The potential adverse effect s of the proposed action on Floodplain s and

Wetlands must considered. The alternatives retained for consideration will not impact any

identified wetlands in the vicinity of the stockpile fine slag pile.

5.7 Cultural Resources

Section 106 of the National Historic Preservation Act (NHPA) is a potential ARAR for any

potential removal action because: 1) all response actions at a Superfun d site are considered

federal actions of the NHPA; and 2) it has been determined that the AV Smelter (and slag

pile) may be individually eligible. Section 110(f) of the NHPA, which establishes procedures

to minimize harm to National Historic Landmarks, is not applicable to the AV slag pile

because it does not lie within the Leadville National Historic Landmark District.

B-31 Terranext
Executive Order 11593 on the Protection and Enhancement of the Cultural Environment is a

potential ARAR and requires consultation with the Council on the preservation and

enhancement of historic resources if removal activities should threaten them. If historical

and/or archeological data are impacted by removal activities, the Historical and

Archeological Data Preservation Act would also be a potential ARAR. The Archeological

Resources Protection Act of 1979 provides for the protection of cultural resources on public

or Indian land and may be a potential ARAR with respect to removal actions impacting such

properties. The AV slag pile lies entirely within private property.

The State Historical, Prehistorical, and Archeological Resources Act addresses the loaning of

archeological resources on state-owned land to scientific or educational institutions. Should

any potential removal action endanger an archeological site that may necessitate removal of

the resource, the procedures outlined by the Act would be a potential ARAR. In addition ,

should potential removal actions uncover any human remains that are of archeological

interest, the procedures for excavation of remains under the act would also be applicable or

relevant and appropriate. Finally , the State's Register of Historic Places is a potential ARAR

if removal activities may impact an area listed on the Register.

B-32 TerraNext
APPENDIX B, TABL E I POTENTIA L CHEMICA L SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Standards , Requirements,

Criteria, Limitation s

Groundwater:

National Primary Drinkin g Water Standards

National Secondary Drinking Water Standards

Maximum Contaminant Level Goal s

Colorado Ground Water Standards

3

\

Citatio n

40C.F.R . Part 141, Subpart B pursuant to 42 U.S.C . §§

300g-i ancl300j-9.

State: 5 CCR 1003-1

pursuant to C.R.S.

25-l-107(l)(x )

40 C.F.R . Part 143, pursuant

to 42 U.S.C . §§300g-l(c )

and 300J-9

40 C.F.R . Part 141, Subpart F, pursuant to 42 U.S.C . §

300g-l

State: 5 CCR 1002-8 §§

3.11.0-3.11.8

Description

Establishes numeric standards

f or public water systems. Maximum contaminant levels

(MCLs) are established to

protect human life-tim e

drinkin g water exposure.

Establishes aesthetics-related

standards for public water

systems (secondary maximum

contaminant level) .

Establishes drinkin g water

quality goals set at levels of no

known or anticipated adverse

health effects , with an adequate

margin of safety .

Establishes a scheme for

identifyin g groundwater

specified areas, for

classificatio n of Colorado

groundwater and provides

numeric standards.

Potentially Applicable / Relevant and Appropriat e

No/N o

No/N o

No/N o

No/Ye s

Comment

T he shallow alluvial aquifer

at the site is not used as a

drinkin g water source and the State of Colorado has a

comprehensive ground water

classificatio n system and

promulgated numeric

standards equivalent to

(MCLs) . Protects aesthetic character,

n ot relevant to protectio n of

human health or environment.

No non-zero MCLG s set at

level s less than MCL s were

identified for contaminants of

concern.

See section 3.2.

Table 11-1
APPENDIX B, TABL E 1, continued

POTENTIA L CHEMICA L SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Standards , Requirements, Potentially Applicable / Criteria. Limitation s Citatio n Description Relevant and Appropriate Comment

RCRA Groundwatcr Protection 40 CFR §§ 264.92 - 264.101 Establishes standards for No/No The State of Colorado has a Standard (RCRA GPS) groundwater quality related to comprehensive ground water State: 6 CCR 1007-3 RCRA hazardous waste classificatio n system

facilities . includin g numeric standards

equivalent to MCL s and RCRA GPS .

3

I

Table 1 1-2
Standards , Requirements, Criteria. Limitation s

Surfac e Water;

Colorado Water Quality Standards

Federal Water Qualit y Criteria

Air:

National Primary and Secondary Ambien t Air Qualit y Standards

National Emission Standards for Hazardous Air Pollutant s

Q

i

APPENDIX B, TABL E 1, continued

POTENTIA L CHEMICA L SPECIFI C ARAK s FO R TH E STOCKPILE D FIN E SLA G

Citation

State: 5 CCR 1002-8, §§

3.1.0 - 3.1.17

Description

Establishes standards and

classification s for Colorado

surface waters.

40 C.F.R . Part 131, pursuant Set s criteria for surface water

to 33 U.S.C. § 1314 quality based on toxicity to

aquatic organisms and human

health.

40 C.F.R . Part 50, pursuant

to 42 U.S.C . § 7409.

State: C.R.S . 25-7-108, 5 C CR 1001-14.

40 C.F.R . Part 61, Subpart s

N, O, P pursuant to 42 U.S.C . § 7412.

State: C.R.S . 25-7-108, 5 CCR 1001-10

Establishes standards for

ambient air quality to protect

public health and welfare

(includin g standards for

paniculate matter and lead).

Set s emission standards for

designated hazardous

pollutants .

Potentiall y Applicable / Relevant and Appropriat e

Yes/No

No/N o

No/N o

No/N o

Comment

S ee section 3.1.1.

T he State of Colorado has a

comprehensive regulatory

framework for stream

classificatio n and assignment

of ambient water qualit y

criteria addressin g the

contaminants of concern.

Atmospheric emissions of

particulates was not a

contaminant transport

pathway retained for

consideration. Atmospheric emissions was

not a contaminant transport

pathway retained for

consideration.

Table 1 1-3
APPENDIX B, TABLE 2

CHEMICAL SPECIFI C CRITERIA TO-BE-CONSIDERED (TBC) FOR THE STOCKPILED FINE SLAG

Advisories to be Considered and Guidance

Soils:

Toxic Substances Control Act , P CB Spil l Cleanup Policy

Interim Guidance on Establishin g Soi l Lead Cleanup Levels at Superfun d Site s

Revised Interim Soil Lead Guidance for CERCLA Site s and RCRA Corrective Facilitie s

Citation

52 FR 10688 April 2, 1987

E PA Directive #9355.4-02, September 1989.

OSWER Directive #9355.4-

12 July, 1994

Description

Establishes guidance cleanup

levels for PCB contaminated

soils.

Established guidance cleanup

levels for lead contaminated

soils.

Establishes guidance cleanup

levels for lead contaminated

soils.

To Be Considered

N ot considered

Considered

Considered

Comment

There is no evidence that PCB

spill s have occurred.

See section 3.3

See section 3.3

3?

3

I

Table 2 2-1
APPENDIX B, TABL E 3 POTENTIA L ACTION SPECIFI C ARARs FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Relevant and Appropriat e

Solid Waste Disposal Act

Guideline s for the Thermal Processing of Solid Wastes

Guidelines for the Land Disposal

of Solid Wastes

Colorado Regulations Pertaining

to Solid Waste Disposal Site s and Facilities

Guideline s for the Storage and Collectio n of Residential , Commercial, and Institutional Solid Waste

Source Separatio n for Material s Recovery Guidelines

Citatio n

40 C.F.R . Part 240, pursuant

to 42 U.S.G . § 6901, et seq.

40 C.F.R . Part 241, pursuant

to 42 U.S.C . §6901, et seq.

State: 6 CCR 1007-2 pursuant

toC.R.S . 30-20-101 et seq.

40 C.F.R . Part 243, pursuant

to 42 U.S.C . §6901. etseq.

40 C.F.R . Part 246, pursuant

to 42 U.S.C . §6901, et seq.

Description

Prescribes guidelines for

thermal processing of

municipal solid wastes.

Establishes requirements and

procedures for land disposal of

solid wastes at federal

facilities .

Establishes requirements and

procedures 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 residential,

commercial, and institutional

solid wastes.

Potentiall y Applicable / Relevant and Appropriate

No/N o

No/N o

No/N o

No/N o

No/N o

Comment

Thermal processin g is not

among the alternatives

retained for consideration.

The site is not a federal

facility .

T he land disposal of solid

wastes is not among the

alternatives retained for

consideration. N ot relevant.

N ot relevant. Creates no

substantive cleanup

requirements.

QZ

&

Table 3 3-1
Potentiall y Applicabl e or Relevant and Appropriat e

Guideline s for Developmen t and Implementatio n of State Solid Waste Management Plans

Criteria for Classificatio n of Solid Waste Disposal Facilitie s

and Practices

Hazardous Waste Management System: General

Identificatio n and Listin g of Hazardous Waste

Standards Applicabl e to Generators of Hazardous Waste

(V

3

\

Citatio n

40 C.F.R . Part 256, pursuant

to 42 U.S.C . §6901, et seq.

40 C.F.R . Part 257, pursuant

to 42 U.S.C . § 6901. et seq.

40 C.F.R . Part 260, pursuant

to 42 U.S.C . §6921

State: 6 CCR 1007-3 Part

260

40 C.F.R . Part 261, pursuant

to 42 U.S.C . § 6921

State: 6 CCR 1007-3 Part

261, pursuant to C.R.S.

25-15-302

40 C.F.R . Part 262, pursuant

to 42 U.S.C . § 6922

State: 6 CCR 1007-3 Part

262, pursuant to C.R.S .

25-15-302

Description

Establishes requirements for

federal approval of state

programs to regulate open

dumps .

Establishes criteria for solid

waste disposal facilitie s and

practices.

Establishes procedures and

criteria for modification or

revocation of any provision in

part s 260-265.

Defines those solid wastes

which are subject to regulation

as hazardous wastes under 40

C.F.R . Parts 262-265 and Parts

124, 270, 271.

Establishes standards for

generators of hazardous waste.

Potentiall y Applicable / Relevant and Appropriate

No/N o

No/N o

No/N o

No/N o

No/N o

Comment

Creates no substantive

cleanup requirements.

T he land disposal of solid

wastes is not among the

alternatives retained for

consideration.

Creates no substantive

cleanup requirements.

T he fin e slag is not a solid

waste.

T he alternatives retained for

consideration wil l not resul t

in the generation of

hazardous waste.

Table 33-2
Potentiall y Applicabl e or Relevant and Appropriate Citation

Standards Applicabl e to 40 C.F.R . Part 263, pursuant Transporters of Hazardous Waste to 42 U.S.C . § 6923

State: 6 CCR 1007-3 Part

263, pursuant to C.R.S.

25-15-302, 4 CCR 723-18

Standards for Owners and Operators of hazardous Waste Treatment , Storage, and Disposal Facilitie s

Interim Standards for Owners an Operators of Hazardous Waste Treatment , Storage, and Disposal Facilitie s

Standards for the management of Specifi c hazardous Wastes and Specifi c Type s of Hazardous Waste Management Facilitie s

IntelHi Standards for Owners

andaperators of New Hazardous W aQ Land Disposal Facilitie s

40 C.F.R . Part 264, pursuant

to 42 U.S.C. § 6924, 6925

State: 6 CCR 1007-3 Part

264, subparts B, C, D, E, F, G, K, L, and N, pursuant to C.R.S. 25-15-302

40 C.F.R . Part 265

State: 6 CCR 1007-3, Part

265

40 C.F.R . Part 266

State: 6 CCR 1007-3, Part

267

40 C.F.R . Part 267

State: 6 CCR 1007-3, Part

267

Description

Establishes standards which

appl y to persons transportin g

hazardous waste within the U.S. if the transportation

requires a manifest under 40

C.F.R . Part 262.

Establishes standards which

defin e the acceptable

management of hazardous

waste for owners ajnd operators

of facilitie s which treat, store,

or dispose of hazardous waste.

Establishes standards for

management of hazardous

waste during interim status.

Establishes requirements which

appl y to recyclable materials

that are reclaimed to recover

economically significan t

amounts of precious metals ,

including gold and silver.

Establishes minimum national

standards that defin e acceptable

management of hazardous

waste for new land disposal

facilities .

Potentiall y Applicable / Relevant and Appropriate

No/N o

No/N o

No/N o

No/N o

No/N o

Comment

T he alternatives retained for

consideration wil l not result

in transport of hazardous

wastes offsite .

T he alternatives retained for

consideration wil l not involve

the treatment, storage or

disposal of hazardous waste.

T he alternatives retained for

consideration wil l not involve

t he management of hazardous

wastes.

Recovery of precious metal s

was not retained for

consideration.

Part 267 regulation s are no

longer effective after February 13, 1983.

Table 3 3-3
APPENDIX B, TABLE 3, continued

POTENTIA L ACTIO N SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Relevant and Appropriat e

Hazardous Waste Permit Program

Underground Storage Tanks

Safe Drinkin g Water Act

Undergroun d Injectio n Control Regulation s

Citation

40 C.F.R . Part 270

State: 6 CCR 1007-3, Part

100

40 C.F.R. Part 280

Description

Establishes provisions covering

basic EPA permittin g

requirements.

Establishes regulations related

to underground storage tanks.

40 C.F.R . §§ 144.12, Establishes requirements for

144.24, and 144.25, pursuant injection of waste water into

to 42 U.S.C . § 121 (e)(l) well s and aquifers .

Potentiall y Applicable / Relevant and Appropriate

No/N o

No/N o

No/N o

Comment

A permi t is not required for

onsite CERCLA response

actions.

The use of or remediation of

underground storage tanks is

not anticipated.

Undergroun d injectio n is not

anticipated.

I

Table 3 3-4
APPENDIX B, TABLE 3, continued

POTENTIA L ACTION SPECIFI C ARARs FO R TH E STOCKPILE D FIN E SLA G

Potentially Applicable or Relevant and Appropriate Citation Description

Potentially Applicable / Relevant and Appropriate Comment

Clean Water Act

National Pollutan t Discharge

Elimination System

Effluen t Limitation s

Dredge or Fill Requirements

(Sectio n 404)

40 C.F.R . Parts 122, 125

pursuant to 33 U.S.C . § 1342

State: 5 CCR 1002-2, §§

6.1.0 to 6.18.0, pursuant to

C.R.S. 25-8-501

40 C.F.R. Part 440, pursuant

to 33 U.S.C. § 1311

State: 5 CCR 1002-3, §§

10.1 to 10.1.7, pursuant to C.R.S. 25-8-503

40 C.F.R . Parts 230, 231; 33 CFR § § 320-330 and 33 C.F.R . Part 323, Pursuant to

33 U.S.C § 1344

Requires permits for the Yes/No

discharge of pollutant s from

any point source into waters of

t he United States includin g

stormwater.

Set s technology-based effluen t No/No

limitations for categories of

industrial point source

discharges.

Requires permits for discharge No/No

of dredged or filled material

into navigable waters.

See section 4.1, 4.2 and 4.3.

There is no discernible

discharge and categorical

standards have not been

established for slag reuse.

T he alternatives retained for

consideration do not involve

t he dredge or fill of material s

in waters of United States .

3

I

Table 3 3-5
APPENDIX B, TABLE 3, continued

POTENTIA L ACTION SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Relevant and Appropriate

National Pretreatinent Standards

Toxic Pollutan t Effluen t Standards

Clean Air Act

Colorado Air Pollutio n Control Regulations Fugitive Paniculate Emissions

Marine Protection, Research & Sanctuary Act

PC Substances Control Actequirements

I

Citation

40 C.F.R . Part 403, pursuant

to 33 U.S.C . § 1317

40 C.F.R . Part 129, pursuant

to 33 U.S.C . § 1317

State: 5 CCR 1001, Regulation No. 1, Section III. D

13 U.S.C . §§ 1401-1445

15 U.S.C . § 2605(e)

40 C.F.R . Part 761

Description

Set s standards to control

pollutant s which pass through

or interfere with treatment

processes in publicl y owned

treatment works or which may

contaminate sewage sludge.

Establishes effluen t standards

or prohibition s for certain toxic

pollutants: aldrin / dieldrin , DDT , endrin, toxaphene,

benzidine, PCBs.

Requires all sources of

paniculate emissions to apply

technicall y feasible and

economically reasonable

control measures.

Regulates ocean dumping.

Establishes disposal

requirements for PCBs

Potentiall y Applicable / Relevant and Appropriate

No/N o

No/N o

Yes/N o

No/N o

No/N o

Comment

No discharge to a publicl y

owned treatment works is

anticipated.

T he discharge of specified

pollutant s is not anticipated.

Technicall y feasible and

economically reasonable

control measures wil l be

applied to reuse of the

stockpiled fin e slag.

Ocean dumpin g wil l not

occur.

At thi s time it is not

anticipated that remedial

activities wil l involve the

disposal of PCBs.

Table 3 3-6
APPENDIX B, TABLE 3, continued

POTENTIA L ACTION SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Relevant and Appropriat e Citatio n Description

Potentiall y Applicable / Relevant and Appropriate

Uranium Mill Tailing s Radiatio n 42 U.S.C . §§ 7901-7942

Control Act 42 U.S.C. § 2022

Surfac e Minin g Control and Reclamation Act

Occupational Safety an d Health A ct

30 U.S.C . §§ 1201-1328

29 U.S.C . §§ 651-678

Federal Mine Safety and Health 30 U.S.C . §§ 801-962 A ct

Hazardous Material s Transportatio n Act , D.O.T. Hazardous Material s Transportation Regulations

Colaijdo Noise Abatement Stat f

49 U.S.C . §§ 1801-1813,

49C.F.R . Parts 107, 171-

177

State: C.R.S. 25-12-101,

et seq.

Q

I

Establishes requirements No/No

related to uranium mill tailings.

Establishes provisions designed No/No

to protect the environment

from the effect s of surface coal

mining operations.

Regulates worker health and No/No

safety .

Regulates working conditions No/No

in underground mines to assure

safety and health of workers.

Regulates transportation of No/No

hazardous materials

Establishes standards for No/No

controllin g noise.

Comment

Uranium mil l tailings are not

present at the site. N ot relevant. Creates no

substantive cleanup

requirements.

Whil e not an ARAR, these

requirements wil l appl y

during implementation of

remedies at the site.

Whil e not an ARAR, the

requirements wil l be met if it

becomes necessary to access

underground mine workings.

T he offsit e transport of

hazardous material is not

anticipated.

While not an ARAR,

applicable standards will be

met durin g activitie s at the

site.

Table 3 3-7
APPENDIX B, TABLE 3, continued

POTENTIA L ACTION SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Potentiall y Applicable / Relevant and Appropriate Citatio n Description Relevant and Appropriate Comment

Colorado Mined Land State: C.R.S . 34-32-101 Regulates al l aspects of mining, No/No Minin g an d related Reclamation Act et seq. 2 CCR 407-1 including location of reclamation activities wil l not

operations, reclamation, and occur at the site.

other environmental and

socioeconomic impacts.

3

I

Table 3 3-8
APPENDIX B, TABLE 3, continued

POTENTIA L ACTIO N SPECIFI C ARAR s FO R TH E STOCKPILE D FIN E SLA G

Advisories to be

Considered and Guidance Citatio n

Clean Water Act Nonpoint Source Management

E PA Requirements for Water Quality Planning and Management, Nonpoin t Source Management and Control40 CFR Part 130,

§130.6(c)(4)

Description

Establishes Best Management Practices as an acceptable CWA section 208 and 303(e) Water Quality Management Plan element for achieving

water quality goals.

To Be Considered

Considered

Comment

T he nonpoint source

management program, with the

regulatory and nonregulatory

applicatio n of Best Management Practices is an

approach states may use in

developin g acceptable CWA Section 208 Water Qualit y Management Plans. BMPs

would only be an ARAR for

nonpoint source management

where a state has adopted BMPs as part of a dul y

promulgated regulatory

program. Colorado lias not

promulgated BMP-based

nonpoint source control

requirements.

Table 3 3-9
APPENDIX B, TABL E 5

POTENTIA L LOCATION SPECIFI C ARARs FOR TH E STOCKPILED FINE SLA G

Potentiall y Applicabl e or Relevant and Appropriate

National Histori c Preservation Act, Executive Order 11593

Citation

16 U.S.C .

40C.F.R .

36C.F.R .

§470

§ 6.301(b) Part 800

State: C.R.S. 24-80-101-108

Archeological and Historic Preservation Act of 1974

16 U.S.C . § 469

40C.F.R. §6.301(c)

Historic Site s Act of 1935, 16 U.S.C . §§ 461 ct seq

40 C.F.R . § 6.301(a)

3

i

Description

E PA must account for the

effect s of any action on any

property with historic,

architectural , archeological or

cultural value that is listed or

eligible for listin g on the National Register of Historic Places, or the Colorado Register of Historic Places.

Establishes procedures to

preserve historical and

archeological data which might

be destroyed through alteration

of terrain as a result of a

federal construction project or

a federall y licensed activity or

program.

Requires federal agencies to

consider the existence and

location of landmarks on the National Registry of Natural Landmarks to avoid undesirable

impacts on such landmarks.

Potentiall y Applicable / Relevant and Appropriate

Yes/N o

No/N o

No/N o

Comment

Effect s of the alternatives

retained for consideration on

listed properties wil l be

considered.

T he alternatives retained for

consideration wil l not destroy

archeological data as a result of

alteration s in terrain.

Natural landmarks will not be

impacted by the alternatives

retained for consideration.

Table 5 5-1
APPENDIX B, TABL E 5 continued

POTENTIA L LOCATION SPECIFI C ARARs FO R TH E STOCKPILE D FIN E SLA G

Potentially Applicabl e or Relevant and Appropriat e Citatio n

Colorado Wildlife Enforcement Stale: C.R.S . 33-1-101,

and Penalties et sen.

Wildlife Commission Regulation s

Fish an d Wildlife Coordination A ct

State: 2 CCR 405-0

16 U.S.C . §§661-666

40 C.F.R . § 6.302(g)

Endangered Species Act

!I

16 U.S.C . §§ 1531-1543

50 C.F.R . Parts 17, 402

40 C.F.R . § 6.302(h)

State: C.R.S. 33-2-101,

et seq.

Description

Potentially Applicable / Relevant and Appropriate

Prohibit s actions detrimental to No/No

wildlife .

Establishes specific No/No

requirements for protection of

wildlife . Requires consultation when Yes/No

federal department or agency

proposes or authorizes any

modificatio n of any stream or

other water body to provide for

adequate provision for

protection of fish and wildlif e

resources.

Requires that federal agencies No/No

insure that any action

authorized, funded, or carried

out by the agency is not likel y

to jeopardize the continued

existence of any threatened or

endangered species or destroy

or adversely modif y critical

habitat.

Comment

Wildlife wil l not be impacted

by the remedies retained for

consideration.

Wildlife will not be impacted

by the remedies retained for

consideration.

Prior to* modificatio n of water

bodies appropriate agencies

wil l be consulted.

T he alternatives retained for

consideration wil l not

jeopardize the continued

existence of any threatened or

endangered species or destroy

or adversely modif y critical

habitat .

Table 5 5-2
APPENDIX B, TABL E 5 continued

POTENTIAL LOCATION SPECIFI C ARARs FOR THE STOCKPILED FINE SLAG

Potentiall y Applicabl e or Relevant and Appropriate

Coastal Zone Management Act

Citation

16 U.S.C . §§ 1451-1464

Wild and Scenic Rivers Act

Wildernes s Act

Executive Order on Protection

of Wetlands , Executive Order N o. 11990

16 U.S.C . §§ 1271-1287

40 C.F.R. § 6.302(e)

36 C.F.R . Part 297

16 U.S.C . §1311 , 16 U.S.C . §668

50 CFR Part 53, 50 CFR Part

27

40 C.F.R . § 6.302(b) and Appendix A

Description

Prohibits federal agencies from

undertaking any activity that is

n ot consistent with a state's

approved coastal zone

management program.

Establishes requirements

applicable to water resource

development project s affectin g wild, scenic, or recreational

rivers within or studied for

inclusion in the National Wild

a nd Scenic Rivers System.

Limit s activities within areas

designated as wilderness or

within National Wildlif e Refuges .

Requires federal agencies to

evaluate the potential effect s of

actions they may take in

wetlands to minimize adverse

impact s to the wetlands.

Potentiall y Applicable / Relevant and Appropriat e

No/N o

No/N o

No/N o

No/N o

Comment

T he site is not in the vicinit y of

a coastal zone.

T he site is not a wild, scenic,

or recreational river in the National"Wild and Scenic River Systems.

T he fin e slag stockpile are not

located in either a wildernes s

area or a National Wildlife Refuge. Wetlan d are not present and

will not be impacted by the

remedies retained for

consideration.

Table 5 5-3
APPENDIX B, TABL E 5 continued

POTENTIA L LOCATION SPECIFI C ARARs FO R TH E STOCKPILE D FIN E SLA G

Potentiall y Applicabl e or Relevant and Appropriate

Executive Order on Floodplai n Management, Executive Order N o. 11,988

Citation

40 C.F.R . § 6.302(b) and Appendix A

Rivers and Harbors Act of

1899, Section 10 Permit

33 U.S.C . § 403

33 C.F.R . Parts 320-330

Description

Requires federal agencies to

evaluate the potential effect s of

actions they may take in a

floodplai n to avoid, to the

maximum extent possible, the

adverse impacts associated with

direct and indirect development

of a floodplain . Requires permit for structures

or work in or affectin g

navigable waters.

Potentiall y Applicable / Relevant and Appropriate

No/N o

Comment

Floodplain s wil l not be

impacted by the alternatives

retained for consideration.

No/N o Surfac e waters at California Gulch are not navigable within

the meaning of the Rivers and Harbors Act of 1899.

Q

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Table 5 5-4