United States
Environmental Protection
Agency
Office 01
Emergency and
Remedial Response
PB93-964120
EP AIROD/R05-92/215
September 1992
&EPA
Superfund
Record of Decision:
Torch Lake, MI
u . s. En\flro~mefi1ta~ Pfm~tiM Aa~Y
tB HawdOuS Wa$te
: Information Cent"
SA 1 Cbestnut Street@ 9th Root
~4} PA 19107
. Hazardous Waste Collection
Information Resource Center
US EP A Region 3
Philadelphio. PA 19107
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NOTICE
The appendices listed in the index that are not found in this document have been removed at the request of
the issuing agency. They contain material which supplement, but adds no further applicable information to
the content of the document. All supptemental material is. however. contained In the administrative record
for this site.
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50272.101
REPORT DOCUMENTATION 11. REPORT NO. I ~ 3. R8cIpIenI'. A_on No.
PAGE EPA/ROD/R05-92/215
4. TI1I8 8nd SubIItI8 5. Report II8t8
SUPERFUND RECORD OF DECISION 09/30/92
Torch Lake, MI
6.
First Remedial Action - Subsequent to follow
7. Aulhor(a) 8. Performing Org8llIDtion Rept. No.
I. P8rf0rmlng OrgeJniDtion Name 8nd Add.... 10. PtojectlTulllWork Unll No.
11. Con1r8ct(C) or Grant(G) No.
(C)
(G)
1~ SponeorIng Organlullon Nama and -- 13. Type of Rapor1' Paltod CoveI'IKI
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 14.
15. Supplementary Nota.
PB93-964120
16. Abatrac1 (Umll: 200 _rda)
The 2,700-acre Torch Lake site is a copper milling and smelting facility in Houghton
County, Michigan. The site includes tailings/slag piles and beaches on Torch Lake, the
west shore of Torch Lake, the northern portion of Portage Lake, Portage Lake Canal,
Keweenaw Waterway, the North Entry to Lake Superior, Boston Pond, and Calumet Lake in
Lake Linden, Hubbell/Tamarack City, Mason, Michigan Smelter, ISle-Royale, Lake
Superior, Grosse Point, Quincy Smelter, Hubbell, and other areas associated with the
Keweenaw Basin. Land use in the area is predominantly residential and recreational.
Wetlands are located in proximity of some of the tailing piles. The lake, which was
are pository of milling wastes, served as the waterway for transportation to support
the mining industry. Over 5 million tons of native copper were produced from the
Keweenaw Peninsula, and more than half of this was processed along the shores of Torch
Lake. Between 1868 and 1968, approximately 200 million tons of tailings were dumped
into Torch Lake, filling at least 20 percent of the lake's original volume. In the
late 1960's, copper milling ceased. In 1972, a discharge of 27,000 gallons of cupric
ammonium carbonate leaching liquor occurred into the north end of Torch Lake from the
storage vats at the Lake Linden Leaching Plant. The state investigated the spill and
(See Attached Page)
17. Documanl Analyala .. Daacrlpto..
Record of Decision - Torch Lake, MI
First Remedial Action - Subsequent to follow
Contaminated Media: Soil, debris, tailings
Key Contaminants: Organics (PAHs); metals (arsenic, chromium, coppe r, lead)
b. IdentifieraJOpen-Ended Terma
c. COSA 11 FIaIdIGroup
18. Availablily Sl8I8m8nI II. SeCl8'ity Cia.. (Thla Re-,) 21. No. 01 pagea
None 62
20. SeCl8'ity Cia.. (Thla Page) ~ Price
Nnn",
~ .7)
(See ANSl-Z31.18)
Sea InlJlTUcrionlJ on He e-
(Formetly NTl5-35)
Depa..-nl 01 Commerce
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EPA/ROD/R05-92/215
Torch Lake, MI
First Remedial Action - Subsequent to follow
Abstract (Continued)
found no harmful effects associated with the spill; however, discoloration of several
acres of lake bottom was noted. In the 1970's, high concentrations of heavy metals in
the lake's sediments, toxic discharges into the lakes, and fish abnormalities prompted
many investigations into the impact of mine waste disposal. From 1988 to 1989, EPA
performed a removal action that included removing drums and soils to an offsite hazardous
waste landfill. This ROD addresses removal of debris, surface tailings, and slag
pile/beach, and disposal of drums on the western shore of the site, as OU1, and
remediation of slag pile locations through the mid-Keweenaw Peninsula, as OU3. A
subsequent ROD will address areas of potential contamination in and around Torch Lake,
including ground water, submerged tailings at the bottom of the lake, sediment, and
surface water, as OU2. The primary contaminants of concern affecting the soil, debris,
and slag pile/beach are organics, including PAHs; and metals, including arsenic,
chromium, lead, and copper.
The selected remedial action for this site includes soil covering/onsite disposal, and
removal of debris from OU1 and OU3 for offsite disposal. OU1 includes covering the
442 acres of tailings with soil and vegetation in Lake Linden, Hubbell/Tamarack City, and
Mason, and covering 9 acres with soil and vegetation in Hubbell. OU3 includes covering
229 acres with soil and vegetation over OU3 tailings in Calumet Lake, Boston Pond,
Michigan Smelter, Dollar Bay, and Grosse Point. The following areas in OU3 are excluded:
portions of the Isle-Royale tailings that will be developed as a sewage treatment plant,
a residential area, and as a source material to make cement blocks; the area, designated
by the Houghton County Road Commission, for use as source material for road traction
during the winter; the Quincy Smelter area, based on the assumption that this area will
be developed as part of a National Historic Park; and the North Entry, Redridge, and
Freda tailings. The remedy also includes removing debris such as wood, empty drums, and
other garbage for offsite disposal and seeking deed restrictions to control the use of
tailing piles and slag piles/beach. If the Isle-Royale tailings are not covered and
vegetated within 5 years, then these areas will follow the requirements of this ROD. The
estimated present worth cost for this remedial action is $6,126,000, which includes an
annual O&M cost of $109,000 for a 10-year period.
PERFORMANCE STANDARDS OR GOALS:
remedial action.
Soil clean-up levels are not established for this
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TORCH LAKE SITE, HI
OPERABLE UNITS I AND III
PECLARATION FOR THE RECORD OF DECISION
Site Name and Location
Torch Lake Site, Operable units I and III
Houghton County, Michigan
Statement of Basis and PurDose
This decision document represents the selected remedial action for
the Torch Lake site, in Houghton County, Michigan, Operable Units
I and III, which was chosen in accordance with the Comprehensive
Environmental Response, Compensation and Liability Act of 1980
(CERCLA) , as amended by the Superfund Amendments and
Reauthorization Act of 1986 (SARA) and, to the extent practicable,
the National oil and Hazardous Substances Pollution Contingency
Plan (NCP).
This decision is based on the Administrative Record for the Torch
Lake site.
The State of Michigan concurs with the selected remedy.
Assessment of the-;" site
Actual or threatened releases of hazardous substances from this
site, if not addr~ssed by implementing the response action selected
in this Record of Decision (ROq), may present an imminent and
substantial endangerment to public health, welfare, or the
environment.
DescriDtion of ~edv
These operable uJ'fi ts are the first and third of three operable
units for the site. The selected remedial action for these
operable units addresses the tailings and slag piles/beach at the
site. Operable unit II, which is not a part of this ROD, addresses
the groundwater, surface water, and sediments. '
The major components of the selected remedy include:
*
Deed restrictions to control the use of tailing piles so
that tailings will not be left in a condition which is
contrary to the intent of this ROD;
Removai of debris such as woqd, empty drums, and other
garbage in the tailing pilesw for off-site disposal in
order to effectively implement the soil cover. with
~
*
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2
vegetation;
*
soil cover with vegetation in the following areas:
Operable Unit I tailings in Lake Linden,
Hubbell/Tamarack city, and Mason (approximately 442
acres) ,
Operable unit III tailings in Calumet Lake, Boston
Pond, Michigan Smelter, Dollar Bay, and Grosse-
point (approximately 229 acres}, and
pile/beach
in
Hubbell
*
Operable Unit I slag
(approximately 9 acres);
The Isle-Royale tailings in OU III will be excluded from
the area to be covered with soil and vegetation under
this ROD as follows:
The portion of Isle-Royale 'tai~ings ,in OU III which
is being developed as a seWage treatment plant will
be excluded from the ,'area to be covered with soil
and vegetation under this ROD." The part of this
area to be covered by conventional sewage treatment
tanks is approximately 12 acres. The remaining
part, approximately 48 acres, will be covered with
soil and vegetation by the Portage Lake Water and
Sewage Authority as part of the sewage treatment
facility development plan. However, if this area
is not covered and vegetated within 5 years after
the date that the fina~ Remedial Design is
submitted, then this area shall be subject to the
requirements of this ROD; ,,.,.
The portion' of the Isle-Royale tailings which is
designated to be developed as a residential area
will be excluded from the area to be covered with
soil and vegetation under this ROD. This area
covers approximately 90 acres. However, if this
area is not developed as a residential area within
5 years after the date that the final Remedial
Design is submitted,' then this area shall be
subject to the ~equirements of this RODi
The portion of the Isle-Royale tailings which is
, currently being used as source material to make
cement blocks and as a finished block storage area
for the superior Block company will be excluded
from the area to be covered with soil and
vegetation under this ROD. This area covers
approximately 60 acres. However, if any portion of
the area is no longer to be used as a storage and
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3
source area, soil cover with vegetation must be
implemented pursuant to this ROD. The owner and/or
operator of Superior Block Co. must use dust
control measures such as water spray during the
operation of mining and other activities in' order
to reduce the release of dust into the air;
*
The area designated by the Houghton County Road
Commission as source material to spread on the road
during winter to provide traction for motor vehicles will
be excluded from the area to be covered with soil and
vegetation. This area is located in Grosse-Point in OU
III and is estimated to be 46 acres. While this area is
being utilized, the following procedures must be
. observed:
The area should be covered with enough soil to
prevent the release of tailings to the air and
lake;
Excavation should stop at seven (7) feet above the
water table (defined as the average of seasonal
highs and lows over a two year period). This
portion must subsequently be covered with soil or
soil and vegetation;
Once the entire area is excavated to seven (7) feet
above the water table, it must be covered with soil
and vegetation pursuant to this ROD;
*
Assuming that the slag pile located in the Quincy Smelter
area (approximately 25 acres) will be developed as part
of a National Park, no action will be taken. If this
area is not developed as a National Park in the future,
deed restrictions will be sought to prevent the
development q~ residences in the slag pile area; and
-'
*
The North Entry (location 4), Redridge (location 11) and
Freda (location 12) tailings are excluded from the area
to be covered under this ROD. Locations 4, 11, and 12
are along the Lake Superior shore where pounding waves
and water currents will likely retard or destroy any
remedial actions. As a result, U.S. EPA currently
believes it to be technically impracticable to implement
the chosen remedy at these locations. However, the North
Entry (location 4) and Freda (location 12) tailings,
approximately 46 acres, shall be studied during Remedial
Design. If U. S. EPA determines that any portion of these
areas is sufficiently unaffected by Lake Superior wave
activity such that it can be effectively covered with
soil and vegetated, then the unaffected area or areas
shall be subject to the requirements of this ROD.
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4
STATUTORY DETERMINATIONS
The selected remedy is protective of human health and the
environment, complies with Federal and State environmental
requirements that are legally applicable or relevant and
appropriate to the remedial action, and is cost-effective. This
remedy utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable; however, because
treatment of the principal threats of the Site was not found to be
practicable, this remedy does not satisfy the statutory preference
for treatment as a principal element.
Because this remedy will result in hazardous substances remaining
on-site, a review will be conducted within five years after
commencement of remedial action to ensure that the remedy continues
to provide adequate protection of human health and the environment.
£u/tf..
..- : I. . '/ 1
.- tZr/ 7. ttl&.L'
Valdas v. Adamkus
./L Regional Administrator
9';j~/~2
DAte /
l
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RECORD OF DECISION
DECISION SUMMARY
TORCH LAKE SITE
OPERABLE UNITS I AND III
HOUGHTON COUNTY, MICHIGAN
prepared 'By:
U.S. Environmental protection Aqency
R8qion V
chicaqo, Illinois
september, 1992
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I.
II. .
III.
IV.
V.
VI.
VII.
VIII.
IX.
X.
XI.
ROD SUMMARY
TORCH LAKE SUPERFUND SITE
OPERABLE UNITS I AND III
HOUGHTON COUNTY, MICHIGAN
TABLE OF CONTENTS
SITE NAME, LOCATION, AND DESCRIPTION. .
........
SITE HISTORY AND ENFORCEMENT ACTIVITIES
. . . . .
COMMUNITY RELATIONS HISTORY
. . . . . .
........
SCOPE AND ROLE OF REMEDIAL ACTIVITIES
. . . . . . . . .
SITE CHARACTERISTICS.
..............
SUMMARY OF SITE RISKS
. . . . . .
. . . . . .
. . . . .
DESCRIPTION OF REMEDIAL ALTERNATIVES.
. . . . . .
SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
.JP.'i
THE SELE~~ED REMEDY
,\
.......
.......
. . . .
STATUTORY! I'DETERMINATIONS SUMMARY.
. . . .
. . . .
DOCUMENTATION OF SIGNIFICANT CHANGES.
. . . .
. . . . .
'-'
~-
3
7
11
11
12
21
35
39
44
47
51
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ROD StJHMARy
TORCH LAKE SUPERFUND SITE
OPERABLE UNITS I AND III
HOUGHTON COUNTY, MICHIGAN
I.
SITE NAME. LOCATION. AND DESCRIPTION
The Torch Lake superfund site (the "Site") is located on the
Keweenaw Peninsula in Houghton County, Michigan (See Figure 1).
The site includes Torch Lake, the west shore of Torch Lake, the
northern portion of Portage Lake, the Portage Lake Canal, Keweenaw
Waterway, the North Entry to Lake Superior, Boston Pond, Calumet
Lake, and other areas associated with the .Keweenaw Basin. Tailing
piles and slag piles/beach deposited along the western shore of
Tbrch Lake, Northern portage Lake, Keweenaw Waterway, Lake
Superior, Boston Pond, and Calumet Lake are also included as part
of the site. These tailing piles include tailings in Lake Linden,
Hubbell/Tamarack City, Mason, Calume~ Lake, Boston Pond, Michigan
Smelter, Isle-Royale, Lake superior, and Gross Point. The slag
piles/~each are located in Quincy Smelter and Hubbell (See Figure
2) .
The northeast/southwest trending Keweenaw Peninsula lies within the
superior bedrock controlled uplands province of the Lake Superior
basin. Drainage patterns in the peninsula are controlled largely
by bedrock type, and follow faults and fractures in the Precambrian
bedrock. Soils in the area primarily consist of sandy loams, and
silty loams. They are developed in till, outwash, holocene
alluvium, and red clay. The major surface water bodies in the
region comprise the Keweenaw Waterway including Torch Lake, Portage
Lake, and Lake superior. The Torch Lake is a tributary to the
larger Portage Lake which in turn has outlets to Lake superior via
the Portage Canal 14 miles to the northwest and to Keweenaw Bay via
the Portage River. Streams in the region drain to the Keweenaw
Waterway and Lake Superior. The Torch Lake watershed comprises
about 12 percent of the larger Portage Lake basin. Forest
vegetation in the area is primarily coniferous. spruce, larch,
fir, and pine are the common species. Deciduous vegetation also
occurs in the area although to a lesser degree. Important species
include sugar maple, birch, and aspen.
Several small communities are located on the west shore of Torch
Lake, the largest of which are Lake Linden, Hubbell/Tamarack city,
and Mason. Two large cities, Houghton and Hancock, are located on
the south and north side of Keweenaw Waterway. Calumet city is
located 5 miles north of Torch Lake (See Figure 2).
Torch Lake has a surface area of approximately 2,700 acres,
depth of 56 feet, a maximum depth of 115 feet, and a volume
X 109 cubic feet. The Trap Rock river and several small
discharge into Torch Lake.
a mean
of 5.2
creeks
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figure 1
CANADA
WISCONSIN
Donohue
; MARCH 1988
SITE LOCATION MAP
TORCH LAKE
REMEDIAL INVESTlGATlON/FEASIBIUTY STUCY
HOUGHTON COUNTY, MICHIGAN
~
IV
EnQin..r. . A,drit.ct.. Scl8ftft8ts
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Figure 2
A
. S
u
.
l"
I
f..&
.~
. I
....- ---
LEGIND
-"". --
~I \,88t8 ...... .....
ItOAO ITSnIlS
sTaft T-
-"- -=-
ca8lfT ,,- ~
..-&lIT _T
ern CIII ft.UII&
$TMIT
([)
-
..'~. ~-
POOR QUAU1'l
ORiG\NAL
~"
Donohue
JUNE ,...
TORCH LAKE SITE
TOACH LAKE
REMEDIAL INVESTIGATION / FEASIBILITY STUDY
HOUGHTON COUNTY. MICHIGAN
~
'"
f r\q'",'" . ,,'C"I'.C'. . Sc......,..
c - ~1I3Z
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6
Torch Lake is used for fishing, boating, limited contact recreation
(swimming), non-contact cooling water supply, treated municipal
waste assimilation, and wildlife habitat. The Village of Lake
Linden has been developing a facility. with a bathing beach,
camping, park, and boat ramps at the northeast end of the Torch
Lake.
The municipal well for Lake Linden is located upstream of the Trap
Rock river, 0.7 miles north of Lake Linden. The supply of drinking
water for Hubbell/Tamarack city is piped from wells located on the
shore of Lake superior, 9 miles west of Torch lake. The municipal
well for Mason is located on the tailing pile in Mason, and the
municipal well for Houghton is located on the Isle-Royale tailing
pile. The municipal well for Hancock is located in Adams Township,
5' miles southeast of Hancock. Several homes are located in the
Isle-Royale tailing pile with their own private wells. (See section
v, below) .
Wetlands are located on the east portion of the Lake Linden tailing
pile, on the eastern edge of the Hubbell tailing pile, around
Boston Pond, and the eastern shore of Torch Lake. Two nests of
bald eag les , which are designated as Endangered Species, are
located on the northern side of Portage Lake. The site does not
lie within the 100 year flood-plain. The Quincy Mining Company
Historic District and Calumet Historic District, which were
proposed as a National Historical Park in September 1987, are
located within the site.
While most of the area of the various:tailing piles are barren and
unused, there is some development on the tailing piles. Two sewage
lagoons are located on the Lake Linden tailing pile. Two sewage
lagoons are also located on the Hubbell/Tamarack City tailing pile.
portage Lake Water and Sewage Authority has set aside 12 acres pn
the ISle-Royale tailings to construct a sewage treatment plant.
Construction of the plant is on-going. superior Block Co., located
on the Isle-Royale tailing pile, is currently utilizing 60 acres of
the Isle-Royale tailings for the production and storage of cement
blocks. The residential homes located on Isle-Royale tailing are
estimated to cover 10 acres of surface area. The city of Houghton
indicated that the city has a plan to develop approximately 90
acres of ISle-Royale tailings into a residential area. The plan
includes covering the tailings with two feet of clean soils and is
expected to be implemented within the next five years. The
Houghton County Road commission is currently using tailing
materials, approximately 46 acres at Grosse-Point, to spread on
the roads during winter to provide traction for motor vehicles.
Tailings also had been use.d in the past as a base for road
construction because of good drainage characteristics.
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7
II.
SITE HISTORY AND ENFORCEMENT ACTIVITIES
Torch Lake was the site of copper ~illing and smelting facilities
and operations for over 100 years. The lake was a repository of
milling wastes, and served as the waterway for transportation to
support the mining industry. The first mill opened on Torch Lake
in 1868. At the mills, copper '.'las extracted by crushing or
"stamping" the rock into smaller pieces, grinding the pieces, and
driving them through successively smaller meshes. The copper and
crushed rock were separated by gravimetric sorting in a liquid
medium. The copper was sent to a smelter. The crushed rock
particles, called "tailings," were discarded along with mill
processing water, typically by pumping into the lakes.
Mining outpu~, milling activity, and tailing production peaked in
the Keweenaw Peninsula in the early 1900s to 1920. All of the
mills at Torch Lake were located on the west shore of the lake and
many other mining mills and smelters were located throughout the
peninsula. In about 1916, advances in technology allowed recovery
of copper from tailings previously deposited in Torch Lake.
Dredges were used to collect submerged tailings, which were then
screened, recrushed, and gravity separated. An ammonia leaching
process involving cupric ammonium carbonate was used to recover
copper and other metals from conglomerate tailings. During the
1920s, chemical reagents were used to further increase the
efficiency of reclamation. The chemical reagents included lime,
pyridine oil, coal tar creosotes, 'dood creosote, pine oil, and
xanthates. After reclamation activities were complete, chemically
treated tailings were returned to the lakes. In the 1930s and
1940s, the Torch Lake mills operated mainly to recover tailings in
Torch Lake. In the 1950s, copper mills were still active, but by
the late 1960s, copper milling had ceased.
Over 5 million tons of native copper was produced from the Keweenaw
Peninsula and more than half of this was processed along the shores
of Torch Lake. Between 1868 and 1968, approximately 200 million
tons of tailings were dumped into Torch Lake filling at least 20
percent of the lake's original volume.
In June 1972, a discharge of 27,000 gallons of cupric ammonium
carbonate leaching liquor occurred into the north end of Torch Lake
from the storage vats at the Lake Linden Leaching Plant. The
MiChigan Water Resources Commission (MWRC) investigated the spill.
The 1973 MWRC report discerned no deleterious effects associated
with the spill, but did observe that discoloration of several acres
of lake bottom indicated previous discharges.
In the 1970s, environmental concern developed regarding the
century-long deposition of tailings into Torch Lake. High
concentrations of copper and other heavy metals in Torch Lake
sediments, toxic discharges into the lakes, and fish abnormalities
prompted :many investigations into long-and short-term impacts
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8
attributed to mine waste disposal. The International Joint
Commission Water Quality Board designated Torch Lake as a Great
Lakes Area of Concern in 1983. Also in 1983, the Michigan
Department of Public Health announced an advisory against the
consumption of Torch Lake sauger and walleye. The Torch Lake site
was proposed for inclusion on the National Priorities List (NPL) in
October of 1984. The site was placed on the NPL in June 1986. The
Torch Lake site is also on the Act 307 Michigan Sites of
Environmental Contamination Priority List.
A Draft Remedial Action Plan ("RAP") for Torch Lake was developed
by MDNR in October, 1987 to address the contamination problems and
to recommend the remedial action for Torch Lake. Revegetation of
lakeshore tailings to minimize air-borne particulate matter was one
of the recommended remedial actions in the RAP.
Attempts to establish vegetation on the tailing piles in
Hubbell/Tamarack City. have been conducted since the 1960s to
stabilize the shoreline and to reduce air particulate from
tailings. It has been estimated that 40 to 50 percent of tailings
in this area are vegetated. The portage Lake Water and Sewage
Authority has been spray-irrigating sewage sludge on tailings in
Mason to promote natural vegetation.
On May 9, 1988, Remedial Investigation/Feasibility Study (RI/FS)
Special Notice Letters were issued to Universal oil Products (UOP)
and Quincy Mining Co. UOP is the successor of Calumet Hecla Mining
Company which operated its milling and smelting on the shore of
Lake Linden and disposed the generated tailings in the area.
Quincy Mining Co. conducted smelting operations in the Hubbell area
and disposed of tailings. On June 13, 1988, a Notice Letter was
issued to Quincy Development Company, which was the current owner
of a tailing pile located on the lake shore in Mason. Negotiations
for the RI/FS Consent Order with these potentially Responsible
Parties (PRPs) were not successful due to issues such as the extent
of the Site, and the number of PRPs. subsequently, U.s. EPA
contracted with Donohue & Associates in November 1988 to perform
the RI/FS at the site.
Due to the size and complex nature of the Site, three Operable
Units ("OUs") have been defined for the site. Torch Lake and the
surroundinq shoreline comprise OU I and OU II. OU III consists of
locations outside this area. Figure 3 shows the location of OU I
and OU III. This ROD is being developed for operable Units. I and
III.
OU I includes surface tailings, drums, and slag pile/beach ~n the
western shore of Torch Lake. An estimated 440 acres of ta1lings
are exposed surficially in OU I. A smaller deposit of smelter slag
pile/beach, encompassing approximately 9 acres, is located near
Hubbell, south of the Peninsula Reclamation Plant.
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9
OU II includes groundwater, surface water, submerged tailings and
sediments in Torch Lake, Portage Lake, the Portage Channel, and
other water bodies at the site.
OU III includes tailings and slag deposits loca~ed in the north
entry of Lake superior, Michigan Smelter, Quincy Smelter, calumet
Lake, Isle-Royale, Boston pond, and Grosse-Point. Figure 3 shows
the locations of the OU III sampling locations. Quincy Smelter
(Location 6) is part of the Quincy Mining Historic District which
is proposed as the National Historical Park.
Depending on the boundary of the proposed National Historic Park
for the Calumet Historic District, the Calumet Lake tailings
(Location 1) might be part of the proposed National Historic Park.
The Remedial Investigations (RI) have been completed for all three
operable units. The RI and Baseline Risk Assessment (BRA) reports
for OU I were finalized in July 1991. The RI and BRA reports for
OU III were finalized on February 7, 1992. The RI and BRA reports
for OU II were finalized in April 1992. The Ecological Assessment
for the Site was finalized in May 1992. The Feasibility Study (FS)
and Proposed Plan which contains the u.S. EPA'S recommended remedy
for OU I and III were issued to the public on May 1, 1992. U.S.
EPA is currently evaluating the scope of FS for OU II, and the.FS
and Proposed Plan for OU II are expected to be issued to the public
in late Fall of 1993.
On June 21, 1989, U.S. EPA collected a total of eight samples from
drums located in the old Calumet and Hecla smelting mill site near
Lake Linden, Ahmeek Mill site near Hubbell, and Quincy site near
Mason. On August 1, 1990, nine more samples were collected from
drums located above the Tamarack site near Tamarack city. Based on
the results of these samples, U.S. EPA determined that some of
these drums may have contained hazardous substances. During the
week of May 8, 1989, the U.S. EPA also conducted ground penetrating
radar and a subbottom profile (seismic) survey of the lake bottom.
The area in which this survey was conducted is immediately off-
shore from the old Calumet and Hecla smelting mill site. The
survey located several point targets (possibly drums) on the bottom
of Torch Lake. Based on the drum sampling results and seismic
survey, U.S. EPA executed an Administrative order by consent, dated
July 30, 1991, which required six companies and individuals to
sample and remove drums located on the shore and lake bottom.
Pursuant to the Administrative Order, these entities removed 20
drums with unknown contents from off-shore of Peninsula copper
Inc., and the old Calumet and Hecla smelting mill site in september
1991. 808 empty drums were found in the lake bottom. These empty
drums were not removed from the lake bottom. A total of 82 drums
and minor quantities of underlying soils were removed from the
shore of Torch Lake. The removed drums and soils were sampled,
overpacked, and disposed off-site at a hazardous waste landfill.
-------
Figure 3
Torch Lake Site
Operable Unit III Locanons
we Supenor
~
N
Torch Lake
-.
Lake Superior
NOT TO SCALE.
1 = Calumet LakrJCopperCty
2 = Calumet Poor Rock
3 = Bosmn Pond
4 - Nonh Entry
5 :8 Adamic Saunp MiD/Michigan Smela:r
6 - Quincy Smela:r
7 -Isle Royale Slimp MiD
8 - Cadc Mi&ILake Supc:riar
9 - Omss Poim.(Fmak1in Stamp MiD)
10 -Gross Point (~~lni.1 Stamp MiD)
11 - BalIidAtJamic Stamp MiDs
12 - AdvamJrdI'rlmDumaiDIQampin "Slimp Mills
-------
11
III.
COMMUNITY RELATIONS ACTIVITIES
A Community Relations Plan for the site was finalized in July 1988.
This document lists contacts and interested parties throughout the
local government and community. It also establishes communication
pathways to ensure timely dissemination of pertinent information.
An RI "Kickoff" meeting was held on August 8, 1989 to explain the
RI process for the site. A fact sheet was developed in conjunction
with this meeting. Advertisements were placed in the Daily Mining
Gazette and a press release was sent to all local media.
A public meeting was held on August 27, 1990 to explain the results
of the OU I investigation and the scope of work for the au II and
1.11 investigations. A fact sheet was developed in conjunction with
this meeting. Advertisements were placed to announce the meeting
and a press release was sent to all local media.
A public meeting was held on October 17, 1991 to update the
investigation results for OUs II and III, and the drum removal
activity. A fact sheet was developed in conjunction with this
meeting. Advertisements were placed to announce the meeting and a
press release was sent to all local media.
The RI/FS and the Proposed Plan for OUs I and III were released to
the public in May 1992. All of these documents were made available
in the information repositories maintained at. the Lake Linden-
Hubbell Public Library and portage Lake Dist;ict Library. An
administrative record containing these documents and other site-
related documents was placed at the Portage Lake District Library.
The notice of availability of these documents was published in the
Daily Mining Gazette on April 29, 1992. Press releases were also
sent to all local media. A public comment period was held from May
1, 1992 to June 1, 1992. Requests for an extension of the comment
period were made and the public comment period was extended until
July 13, 1992. In addition, a public meeting was held on May 12,
1992 to present the results of the RI/FS and the recommended
alternatives as presented in the Proposed Plan for the site. All
comments which were received by u.S.. EPA during the public comment
period, including those expressed verbally at the public meeting,
are addressed in the Responsiveness Summary which is the third
section of this ROD.
IV.
SCOPE AND ROLE OF OPERABLE UNIT
As discussed in section III, U.S. EPA has divided the site into
three operable units. Operable Unit I consists of surface tailings
and the slag pile/beach, and disposed drums on the western shore of
Torch Lake. Operable Unit II includes areas of potential
contamination in and around Torch Lake, including groundwater,
submerged tailings at the bottom of the lake, sediment, and surface
water. Operable unit III consists of 12 areas of tailings and slag
-------
12
pile locations throughout the mid-Keweenaw Peninsula. Operable
Units I and III are the subject of this Record of Decision.
U. s. EPA identified contaminated surface tailings and the slag
piles/beach located in Operable units I and III as potential risks
to human' health and the environment. To address these risks, U.s.
EPA developed the following remedial objectives for Operable units
I and III based on the data obtained during the RI:
1.
Reduce or minimize potential risks to human health
associated with the inhalation of airborne contaminants
from the tailings and/or slag located at the Site;
Reduce or minimize potential risks to human health
associated with direct contact with and/or the ingestion
of the tailings and/or the slag located at the Site;
2.
3.
Reduce or minimize the release of contaminants
tailings to the groundwater through leaching; and
in
Reduce. or minimize the release of contaminants in
tailings to the surface water and sediment by soil
erosion and/or air deposition.
This ROD was developed to meet these objectives and it addresses
the contamination problems identified in operable Units I and III.
This response action is being implemented to protect human health
and the environment from risks posed by the contamination problems.
4.
This present response action, by addressing contaminated surface
tailings and slag piles/beach in Operable units I and III, is fully
consistent with all future site investigation and cleanup work,
including the on-going' study in operable unit II-The
contamination problems in and around Torch Lake, including
groundwater, sediments, submerged tailings, surface water, and the
risks posed thereby will be evaluated and addressed during Operable
unit II. .
v.
SITE CHARACTERISTICS
In November 1990 and January 1992, a Remedial Investigation (RI)
report for Operable Unit I and Operable Unit III was completed.
The RI for Operable Units I and III was to determine the nature and
extent of contamination in the surface tailings. and slag
piles/beach deposited on the shore of Torch Lake and other water
bodies at the Site, and evaluate possible exposure pathways. These
reports summarized all sampling of the surface tailings and slag
piles/beach, drums, residential soil, background soil, air
monitoring, and site survey data that had been collected. In
addition, a RI report for Operable Unit II was completed in January
1992. The RI for Operable unit II was to determine the nature and
extent of contamination in the groundwater, surface water,
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..
13
submerged tailings, and sediments of Torch Lake and other water
bodies in the site. This report summarized all groundwater,
surface water, and sediment data that had been collected. u.s. EPA
also conducted long-term leachability tests for tailings, a fish
reproduction study, a bald eagle and' bird study, a bio-assay test
for the sediment and surface water of Torch Lake, fish survey,
wetlands identification study, Toxicity Characteristic Leaching
Procedure (TCLP) test for tailings and the slag piles/beach, and a
treatability study for soil cover with vegetation. These reports
should be consulted for a more thorough description of the site.
Although this ROD does not address the contamination problems for
OU II, the data collected during the RIot OU II are discussed in
orper to determine the nature and extent of contamination problems
'in OU II caused by the contaminants located in Operable unit I and
III.
The following are the results of the RI at the Site:
Based on the site survey activity conducted during the RI, the
following acreage was estimated for each tailing and slag
pile/beach:
Area
(acres)
124
121
197
9
OU I :
Lake Linden tailings
Hubbell/Tamarack city tailings
Mason tailings
Hubbell slag pile/beach
OU III:
Calumet Lake tailings (location 1)
Calumet Poor Rock (location 2)
Boston Pond tailings (location 3)
North Entry tailings (location 4)
Michigan Smelter tailings (location 5)
Quincy Smelter slag (location 6)
Isle-Royale tailings (location 7)
Dollar Bay slag (location 8)
Grosse-Point tailings (location 9)
Grosse-Point tailings (location 10)
Redridge tailings (location 11)
Freda tailings (location 12)
2
65
46
23
25
223
28
63
94
85
4
An archive search was conducted to determine the type and
source of tailings in OUs I and III. Based on this search,
tailings were assigned to sectors which reflect uniqueness of
tailing type and source. The tailings in OUs I and III are
either red conglomerate or black amygdaloid tailings.
Ambient air samples were collected in the Torch Lake area to
determine the type and level of contaminants in the air
released from tailing piles. contaminants such as arsenic
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14
(0.0016 !J.g/mJ), cadmium (0.0276 !J.g/mJ), and copper (0.202
!J.g/m3) were detected in the air. The highest PM\O
concentrations predicted by mOdeling was 42 !J.g/mJ in OU I and
16 !J.g/mJ in OU III. The National Ambient Air Quality standard
for PM!o is 50 /J.g/mJ. It should be noted that cadmium was not
found in OU I tailings, but was found in OU III tailings.
Magnetometry and ground penetrating radar surveys were
conducted on OU I tailings to locate buried drums. A
geophysical survey utilizing a remotely operated vehicle to
locate drums in the lake bottom was also conducted. Based on
ground-surface geophysical survey data, 10 test pits were
excavated in OU I tailings area. No drums were discov~red. .
Drums exposed on the surface were sampled. One overturned and
leaking drum contained 4,000 parts per million (ppm) of
trichloroethylene. . Composite samples from these drums
indicate that these drums contained hazardous substances.. A
total of 82 drums and minor quantities of underlying soils,
along with 28 drums containing unidentified materials from the
bottom of Torch Lake, were removed from the shore of Torch
Lake. The removed drums and soils were sampled, overpacked,
and disposed off-site in a hazardous waste landfill.
Prior to the field sampling, field monitoring was conducted to
detect alpha/beta/gamma radiation using a Monitor 4 detector.
No radiation readings above background were measured for any
tailing sample.
composite samples were collected from tailings and slag
pile/beach in OU I. Two classes of Semi-Volatile Organic
Compounds (SVOCs), phthalates and polycyclic aromatic
hydrocarbons- (PAHs) and inorganic compounds were found in
surface tailings and slag pile/beach in OU I. Bis (2-
Ethylhexyl)phthalate (1.2 mg/kg), naphthalene (0.17 mg/kg),
benzo(k)fluoranthene (0.56 mg/kg), benzo(a)pyrene (0.44
mg/kg), arsenic (8.3 mg/kq), chromium (46.3 mg/kg), copper
(3,020 mg/kg), and lead (104 mg/kg) were found in OU I
tailings. Bis(2-Ethylhexyl)phthalate (0.11 mg/kg), arsenic
(118 mg/kq), chromium (649 mg/kg), copper (12,800 mg/kg), and
lead (113 mg/kg) were found in OU I slag pile/beach. No PCBs
or Pesticides were detected in OU I tailings (See Table 1).
-------
Table 1
Summary or Chemicals of Potential Concern - Tailings and Slag Piles/Beach
Operable Units I and III
Maximum Concentration Detected I
Residence' I
ContaminantS au I (mg/kg) au III (mg/kg) BG (mg/kg) (mgikg) I
Inon/anics Tailinlls1 Sla~ Tailinlls: ~
Aluminum 37.200 32.900 51. 000 63.900 13,200 7,600
Antimony 11.7 10 23.2 164 10.5 ND
Arsenic 8.3 118 55.82 37.8 6.3 7
Barium 135 392 645 323 31.8 101
Beryllium 1.7 1.4 2.2 1.9 0.35 ND
Cadmium ND ND 9.8 13.9 0.69 1.40
ChrolDJum 46.3 649 303 745 23.3 20.1
Cobalt. 52.6 20.4 44.7 67.9 18.0 ND
Copper 4.360 12.800 13.100 13.500 1.670 459
Lead 104 113 63.6 .21.1 52.6 329
Manganese 1.080 561 1,000 1.640 404 357
Mercury 1.1 0.12 0.14 0.21 0.20 0.47
Nickel 57.3 19.4 149 29.9 27.1 33.7
Silver 8.2 3.6 52.3 8.6 ND ND
Thallium ND ND 0.43 ND ND ND
Vanadium 159 115 164 197 40.7 26.3
Ornnics
bis(2-Ethylhex yl)phthalate 1.2 0.11 0.12 ND 925.000 3.8
Butylbenzylphthalate ND ND ND 0.36 ND 0.110
Diethylphtbalate ND ND 2.5 ND ND ND
Naphthalene 0.17 ND ND ND 5.000 0.071
2-Methylnaphthalene 0.24 ND ND ND ND 0.054
Acenaphthylene 0.037 ND ND ND ND 0.130
Phenanthrene 0.27 0.045 ND ND ND 1.9
Fluoranthene 0.4 ' 0.081 ND 0.068 40 2.8
Pyrene 0.39 0.07 0.067 0.081 15 2.6
Chrysene' 0.41 0.058 0.071 ND 5.000 1.6
Benzo(b )f1uoranthene 0.56 0.042 0.07 ND 30 1.5
Benzo(k)f1uoranthene 0.56 ND 0.07 ND 15 0.970
Benzo( a)pyrene 0.27 ND ND ND 8.000 1.6
Indeno( 1.2.3
-------
16
Composite samples were collected from tailings and slag pile
in OU III. No SVOCs were detected above the Contract Required
Quantification Limits (CRQL). Inorganic compounds such as
arsenic (55.8 mg/kg), cadm~um (13.9 mg/kg), chromium (745
mg/kg), copper (15,900 mg/kg), and lead (39.6 mg/kg) were
detected in OU III tailings. Arsenic (150 mg/kg), and lead
(63.6 mg/kg) were detected in OU III Quincy Smelter slag pile
(See Table 1).
Geotechnical analysis was done for tailings, and slag samples
collected in OU I and III to determine moisture content, grain
size distribution, Atterberg Limits, water holding capacity,
volume calculations, and cation exchange capacity. The
results of this analysis indicate that surface tailings in OU
I are predominantly silty sands and poorly graded sand with
silt. The most heavily vegetated tailings exhibit the
greatest moisture content. Water holding capacity ranges from
22 to 43 percent.
Eleven soil samples were collected from nine residential
backyards and a football field in Lake Linden, Hubbell/
Tamarack city, and Mason to determine if contaminants from the
tailings along the Torch Lake have impacted soil adjacent to
or near the tailing sources. PAR compounds such as
benzo(a)pyrene (1.6 mg/kg), pyrene (2.6 mg/kg), and inorganic
compounds such as arsenic (7 mg/kg), chromium (20.1 mg/kg),
copper (459 mg/kg), and lead (329 mg/kg)-were detected in the
residential soil. The U.S. EPA has determined that the level
of these contaminants does not pose a significant threat to
human health (See Table 1).
Four soil background samples were collected from the Torch
Lake area which were not affected by tailing deposition.
Bis (2-ethylhexyl phthalate (925 mg-/kg), naphthalene (5 mg/kg) ,
and benzo(b)fluoranthene (O~03 mg/kg) were detected in the
background soil samples. Inorganic compounds such as arsenic
(6.3 mg/kg), chromium (23.3 mg/kg), copper (1,670 mg/kg), and
lead (52.6 mg/kg) were detected (See Table 1).
TCLP tests were conducted for the tailings and slag pile/beach
in OU I to determine the leachability of the contaminants in
tailings and slag piles/beach. cadmium, copper, and lead were
detected in leachate above the background level.
Eight groundwater monitoring wells were installed in the OU I
tailings to evaluate groundwater flow direction and to
determine if contaminants are leaching from the tailings into
groundwater. Groundwater flow within OU I tailings is to the
south-southeast with groundwater discharge to Torch Lake.
Acetone (14 ~g/l), bis (2-Ethylhexyl) phthalate (36 ~g/l),
arsenic (25.2 ~g/l), chromium (119 ~g/l), copper (6,150 ~g/l),
-------
-------
Table 2
Summary of Chemicals of Potential Concern
Surface Water and Groundwater in Torch Lake
Maximum Concentration Detected -.
- -
- .
Contaminants Surface Water (ug/l) Groundwater (ug/l)
Inorllanics Torch Lake Keweenaw Waterwav BG Torch Lake area BG Residential
Aluminum 958 178 57.6 84.300 76.4 50.2
Antimony 27.8 ND ND 31 ND 3.0
Arsenic 3.4 5.7 2 25.2 ND 4.5
Barium 66.4 18.4 15.8 1.320 U8 145
Beryllium ND ND ND 2.2 ND 1.0
Cadmium 11.1 ND ND 3.7 0.33 0.10
Chromium 8.8 ND ND 119 ND 6.0
Cobalt '4 ND ND 117 ND 8.0
Copper 73.8 44.4 ND 6.150 48.4 154
Lead 7.2 1.2 2.5 39 ND 1.0
Manganese 100 48 14.2 3.730 73.3 137
Mercury 98 ND ND ND ND 0.20
Nickel 26.5 206 ND 131 ND 13.0
Potassium 2.200 ND ND 7.820 NA 3.030
Selenium 3.3 ND ND 10.6 NA 2.0
Silver ND ND ND ND ND 3.0
Sodium 26.600 ND 2.000 104.000 NA 18.900
Thallium ND ND ND ND NA 1.1
Vanadium 4.3 . ND ND 341 ND 7.0
.JJ.;:~
,
Orllanics
1!(\
Acetonc 2S \ ND
i NO ND 14 ND
bis(2-Ethylhcxyl)phthalate 89 .' ND ND 36 9 ND
Butylbenzylphthalate 6.0 ND ND ND ND ND
Diethylphthalate NA ND ND NA ND ND
Naphthalenc ND ND ND ND ND ND
2-Methylnaphthalenc ND...."., ND ND ND ND ND
Accoaphthylenc NA ," ND ND ND ND ND
Acenaphthenc ND .~'" ND ND 7 ND ND
Phcnanthn:Dc ND ND ND ND ND ND
Fluoranthenc ND ND ND ND ND ND
Pyrenc ND NO ND ND ND ND
Bcnzo(a)anthraccnc ND NO ND ND Nt) ND
Chryscoc ND ND ND ND ND ND
Benzo(b )t1uoran&heae ND ND ND ND ND ND
Bcnzo(k)fluonmthcae ND ND ND ND ND ND
Bcnzo(a)pyrenc ND ND ND ND ND ND
Indeno( 1.2.3~)Pyrene ND NO ND ND NO NO
Dibcnzo(a.h)anthraceae NO NO ND ND NO NO
Bcnzo(g ,h,i)perylcnc ND ND ND ND ND ND
".
Benzoic acid ND NO ND ND ND NO
Dibcnzofuran ND ND ND ND NO NO
Phenol NO ND ND ND NO NO
Toluene NO ND ND ND ND NO
BG:Background
ND:Not Detected
NA:Not Analyzed
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Table 3
Summary of Chemicals of Potenual Concern
Sediments in Torch Lake and Keweenaw Waterway
Maximum Concentration Detected (mg/kg)
Contaminants Torch Lake Keweenaw Waterway BG
Ino(llanics All Samples Excluding SD9 and SD 10
Aluminum 45.100 45.100 44.000 11.000
Antimony 28.4 28.4 21.8 ND
Arsenic 4.560 41.2 311 5.6
Barium 227 227 129 95.1
Beryllium 1.6 1.6 0.92 0.29
Cadmium 57.2 0.81 3.1 ND
Chromium 179 83.S 124 .16.8
Cobalt 74.5 74.5 55.0 9.9
Copper 6.890 3.760 4.200 47.6
Iron 72.700 72.700 57.000 22.300
Lead 2.240 187 93.6 27
Manganese 3.310 3.310 1.250 459
Mercury 0.75 0.75 0.54 ND
Nickel 196 130 131 11.7
Silver 41.9 10.2 2.7 ND
Vanadium 199 199 149 42.3
Ornnics
Acetone ND ND 260 0.048
Toluene 0.053 0.053 ND 0.002
bis(2-Ethylhexyl)phthalate 2.0 2.0 280 ND
Naphthalene 1.1 ND ND ND
2-Methylnaphthalene 0.73 ND 79 ND
Acenaphthene 6.7 ND 95 ND
Phenanthrene 53 0.49 1.400 ND
Fluoranthene 58 0.92 1.600 ND
Pyrene 50 1.3 1.600 ND
Benz.o(s )anthracene .42 0.48 810 ND
Chrysene 30 0.6 940 ND
Benzo(b )fluoranthene 17 ND 1.400 ND
Benz.o(k)fluoranthene 13 0.95 1.100 ND
Benm(a)pyrene 33 ND ND ND
Ineleno( 1.2.3-cd)pyrene 12 ND ND ND
Dibenzo( a.h)anthracene 7.2 ND ND ND
Benzo(g.h.i)perylene 8.4 ND ND ND
Benzoic Acid 0.31 0.31 ND ND
Dibenzofuran 4.1 ND ND ND
Phenol 0.47 0.18 ND ND
BG:Baclcground
ND:Not Detected
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20
A bio-assay test was conducted in the surface water samples
from Torch Lake to determine the chronic effect of
contaminants. The results of this test indicate that surface
water of Torch Lake is not toxic .relative to the test control.
A bio-assay test also was conducted in the sediment samples
from Torch Lake to determine both acute and toxic effect
levels in the Torch Lake sediment. Lethal concentrationsos
(LCsos) for copper as the sole contaminant was calculated as
498 parts per million (ppm) with a 95 percent confidence range
of 480 ppm to 520 ppm. Most of sediment samples collected
from Torch Lake and Keweenaw waterway have higher copper
concentration levels than LCsos. The results of this sediment
bio-assay test indicate that the 'vast majority of the
sediments in Torch Lake are toxic and not able to support a
normal benthic community.
A reproduction study was conducted in bald eagles and gulls
nested in the Portage Lake and Torch Lake areas to determine
whether bald eagles and gulls have been impacted by
contaminants in the tailings. The reproduction study includes
observation of food habits, and analysis of feather, egg, and
blood. Based on the analytical chemistry results for copper,
there does not appear to be any adverse reproductive effect on
gulls or eagles that can be associated with exposure to copper
in the tailings. Reproductive anomalies such as bill defects
in two ring-billed gulls are usually attributed to PCB
pollution in the Great Lakes.
Reproduction by yellow perch was studied to determine if
chronic exposure to elevated copper concentrations in Torch
Lake has reduced the reproductive success of yellow perch.
The results of this study indicate that copper concentration
in Torch Lake did not significantly reduce hatching success.
Duration of hatching was significantly longer for Torch Lake
egg masses than was for reference lake egg masses, indicating
that copper may be affecting hatching rates.
In 1988, 458 fish were collected from the Torch Lake and
Portage Lake and analyzed to determine the presence of fish
contaminants and tumors. only four of the 56 fish analyzed
for mercury had concentrations that exceeded the 0.5 mg/kg
consumption advisory action limit and none exceeded 1.0 mq/kq.
No internal or external growth anomalies were observed among
the 458 fish collected. No liver neoplasms (cancerous
growths) were found among the 47 walleyes collected. Saugers
were not collected in 1988 following an extended period of
population decline which began in the 1960's.
A treatability study is currently being conducted by the 50il
Conservation Service to determine the effectiveness of soil
cover with vegetation in the tailings and slag pile/beach.
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21
The preliminary results of this study indicate that 4 to 6
inches of sandy loam soils with a grass/legume mixture would
be necessary in the non-vegetated area to achieve the
remediation objectives. The study also indicates that a good
maintenance program such as mUlching, fertilizing, .and
irrigation would be necessary to increase the effectiveness of
soil cover with vegetation.
A study was conducted to identify the wetlands located at the
site. The study indicates that wetlands are located in the
Boston Pond, Lake Linden, Hubbell and Portage Canal.
It should be noted that one composite sample per 10 acres for OU I
tailing and one composite sample per 20 acres for OU III tailings
were collected. composite samples consisted of 4 subsamples
collected. This small number of samples is based on the assessment
that the tailings would be homogeneous in terms of their origin and
chemical contents. However, based on the finding of hot-spots in
the sediment, the disposal practice of waste in the tailings, and
the detection of cadmium in the air but not in OU I tailings, it is
possible that concentrations in the tailings would be higher if the
sampling size was increased.
VI. SUMMARY OF SITE RISKS
The baseline risi' assessments for OUs I and III were conducted to
characterize the.. current and potential future threat to public
health that may b~ posed by contaminants in the tailings and slag
piles/beach. The ecological assessment for the entire site was
also conducted to determine the current and potential future
effects of contaminants to the environment. Both current and
potential future use conditions were examined in the baseline risk
assessment. Under current conditions, the site was assessed in the
absence of any r~~edial action for tailings and slag piles/beach.
A risk assessmen"t consists of four primary parts: identifying
chemicals of potential concern; assessing pathways through which
humans, plants, and animals could. be exposed to contamination;
assessing the toxicity of the contaminants; and characterizing
cancerous and non-cancerous health effects on humans. .
a.
Human Health Risks
1.
contaminant Identification
The first step of the risk assessment was to select chemicals of
potential concern for detailed evaluation. This was conducted by
summarizing and evaluating RI data, including a consideration of
the presence of chemicals in blank samples. Based on this
evaluation, 31 chemicals of potential concern were selected for
detailed assessment for OU I. These chemicals were considered most
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22
likely to be of concern to human health and environment. The
fOllowing compounds were selected as the chemicals of potential
concern for OU Ii
organic Compounds
Inorganics
bis(2-Ethylhexyl)phthalate
PAHs
Naphthalene
2-Methylnaphthalene
Acenaphthylene
Phenanthrene
Fluoranthene
pyrene
Benzo(a)fluoranthene
Chrysene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
Indeno(l,2,3-cd)pyrene
Dibenzota,h) anthracene
Benzo(g,h,i)perylene
Aluminum
Antimony
Arsenic
Barium
Beryllium
Boron
Chromium
Cobalt
Copper
Lead
Manqanese
Mercury
. Nickel
silver
Titanium
vanadium
The chemicals of concern for OU III includes cadmium and the
inorganic compounds listed above (except for boron, titanium, iron
and thallium) and 6 orqanic compounds (benzo(b)fluoranthene,
benzo(k)fluoranthene, butyl benzyl phthalate, chrysene,
diethylphthalate, fluoranthene, pyrene, and bis(2-
ethylhexyl)phthalate). .
These contaminants were detected in tailings and slag piles/beach
of OUs I and III. Table 1 identifies the maximum concentration of
contaminants in tailinqs .and slag piles/beach.
2.
Expo~ure Assessment
An exposure assessment was conducted to identify potential pathways
of exposure under both current and future site and surrounding land
use conditions.
Excosure Scenarios for OU I
The exposure pathways quantified in the OU I baseline risk
assessment for current and future populations are based on the
following scenarios:
(a)
Current Populations Exposure Pathways
Adult and child residents in off-site dwellings exposed
to tailinqs, slag, and particulate;
occupational populations (laqoon workers and sludge
spreaders) exposed to tailings and particulate from the
.
.
-------
.
(b)
.
.
23
tailings; and
Adult and child campers exposed
particulate from the tailings.
to
tailings
and
Future populations Exposure Pathways
Adult and child residents of on-site dwellings exposed to
tailings and particulate from the tailings; and
Adult and child residents of off-site dwelling exposed to
tailings and particulate from tailings and slag.
For the ingestion of tailings by curren~ and future residents,
adult residents were assumed to weigh 70 kg and ingest 100 mg of
tailings per day, 365 days per year and to live in the same
location for 70 years of their 70-year expected lifetime. For the
inhalation of air-borne contaminan~s by current and future
residents, adult residents were assumed to weigh 70 kg and inhale
0.84 mJ of air per hour. A frequency of exposure of 365 days per
year, and a duration of exposure of 70 years were assumed.
Scenarios involving children consider chil~~n to be between the
ages of 0 and 6 years old. Generally, children above 6 years old
are assumed to ingest and inhale particulate on a per kilogram
bodyweight basis which is similar to adults. The occupational
populations represent workers at four existing sewage lagoons in
Lake Linden and Tamarack city and workers currently spreading
sewage sludge on tailings in Mason.
The upper bound (95% confidence limit) of the arithmetic average of
concentration of contaminants of concern at each assumed exposure
location was used for tailings and slag piles/beach to calculate
the risk. For the inhalation exposures, the exposure point
concentrations were calculated using air emission and transport
models.
Excosure scenarios for OU III
The exposure pathways quantified in the OU III baseline risk
assessment for both current and future populations are based on the
following scenarios:
(a)
current populations Exposure Pathways
Adult residents of on-site dwellings exposed to tailings
and tailing particulate at the Isle-Royale tailings;
. Adults scavenging in areas of OU III exposed to tailings;
Teenagers scavenging in areas of OU III exposed to
tailings and tailing particulate; .
Workers exposed to tailings and tailing particulate; and
Adult and child visitors exposed to tailings and tailing
.
.
.
.
.
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24
particulate.
( b)
Future populations Exposure Pathways
Adult and child residents of on-site dwellings exposed to
tailings and tailings particulate; and
Workers exposed to tailings.
.
.
(c)
Future National Park Scenario
.
visitors and workers exposed to slag.
The human acti vi ty patterns and physical features of each area were
evaluated to. determine the exposure pathways likely to occur at
each location. The OU III Baseline Risk assessment included the
exposure pathway of "Teenage Scavenger". This separate scenario is
predicated on the exposure of teenagers (considered adults .for
other exposure scenarios) to tailings based on their likely
social/leisure activities which may be around tailings and/or slag
piles. The same exposure factor assumptions were made as in OU I.
3.
Toxicity Assessment
The purpose of the toxicity assessment is to evaluate the available
evidence regarding the potential for a chemical to cause adverse
health effects. This evidence, initially derived through, the
research of the potential cancerous and non-cancerous health
effects (i.e. toxicity) of individual chemicals, is subsequently
obtainable and can be employed'in the assessment of site-related
contamination. In the research of a chemical' s toxicity, the
effects of low levels of chemical exposure on people in the
workplace are studied over long periods of time. Also, test
animals are studied in laboratories, where animals are exposed to
varying levels of chemicals over different lengths of time.
Cancer slope factors have been developed by EPA' s ' Carcinogen
Assessment Group for estimating excess lifetime cancer risks
associated with exposure to potentially carcinogenic chemicals.
Slope factors, which are expressed in units of (mg/kg-day) -I, are
multiplied by the estimated intake of a potential carcinogen, in
mg/kg-day, to provide an upper-bound estimate of the excess
lifetime ,cancer risk associated with exposure at that intake level.
The term "upper bound" reflects the conservative estimate of the
risks calculated from the cancer slope factor. Use of this
approach makes underestimation of the actual cancer risk highly
unlikely. Cancer slope factors are derived from the results of .
human epidemiological studies or chronic animal bioassays. Table
4 contains the cancer slope factors for carcinogenic contaminants
of concern at the site. The cancer risks resulting from these
calculations are expressed in terms of the probability that an
individual exposed .for his or her, entire lifetime will develop
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25
cancer (i.e. one chance in one million = 1 x 10~, one chance in one
thousand = 1 X 10.3). Typically, excess cancer risks of 1 x 10~ or
lower are considered acceptable, while higher excess cancer risk
levels may be cause for concern. U.S. EPA has the discretion to
select remedies resulting in upperbound cancer risks that fall
within. a range of 1 x 10-4 to 1 x 10~ based on site-specific
factors. A cancer risk of 1 x 10~ serves as the point of departure
for U.S. EPA's cancer risk goal when selecting a remedy.
Reference doses (RfDs) have been developed by U.S. EPA for
indicating the potential for adverse health effects from exposure
to chemicals exhibiting non-carcinogenic effects. RfDs, which are'
expressed in units of mg/kg-day, are estimates of the daily
exposure to the human population (including sensitive
subpopulations) that is likely to be without an appreciable risk of
deleterious effects during a chronic or subchronic exposure
duration. RfDs are derived from human epidemiological studies or
animal studies; uncertainty factors are applied to help ensure that
the RfDs will not underestimate the potential for adverse
noncarcinogenic effects. The reference doses for contaminants of
concern at this site are specified in Table 4.
4.
Risk Characterization
ou I Cancer Risks
A summary of cancer risks is presented in Table 5. The OU I risk
assessment results showed that cancer risks to all current
residential populations are equal to or below 1 X 10~ except in the
vicinity of the Hubbell slag pile and slag beach. Cancer risks for
these current residents are 9 X 10~ (inhalation and ingestion at
slag beach) and 9 X 10.; (inhalation and ingestion at slag pile) for
a combined excess cancer risk of 1 X 10-4. However, due to the
nature of the slag and snow cover, this area does not present an
unacceptable health risk to humans. Total cancer risks for future
residents at tailings in Lake Linden, Hubbell/Tamarack city, and
Mason range from 8 X 10~ to 3 X 10.;. The risks are attributable
primarily to arsenic, beryllium, and chromium. As indicated in the
table, cancer risks for children are generally less than cancer
risks for adults.
Risks to lagoon workers range from 8 X 10~ to 1 X 10.;.
is attributable primarily to ingestion of tailings
arsenic and beryllium.
This risk
containing
OU I Non-Cancer Risks
A hazard index, determined by summing the hazard quotients (HQs)
for each chemical, greater than one indicates that some possibility
that non-cancer, chronic or subchronic health effects exists.
Chronic hazard indices do not exceed 1.0 for any exposure pathway
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26
evaluated in OU I. Subchronic hazard indices exceed 1.0 for
exposure pathways involving children at the Lake Linden Campground,
at current residences near the slag pile/beach, and future
residences assumed to be built on the ta~lings piles. Chemicals
contributing to these hazard indices include antimony, arsenic,
barium, chromium, copper, manganese and vanadium. However, since
these chemicals impact different systems and organs in the human
body, it is appropriate to evaluate each chemical separately. In
only one instance did any chemical exceed an HQ of 1.0. At the
slag pile and beach, both copper and arsenic had an HQ of
approximately 2.0 for a current child resident. For the other two
exposure pathways involving children, 1 isted above, which have
subchronic hazard indices which exceed 1.0, copper was the dominant
compound contributing to. the hazard indices' calculations for
ingestion of contaminants. For a future child resident at Mason,
a subchronic inhalation risk was driven by manganese and chromium.
A summary of subchronic non-cancer risks is presented in Table 5.
U.S. EPA has determined that, except at the slag pile/beach, OU I
does not present an unacceptable non-cancer health risk to humans.
OU III Cancer Risks
Estimated cancer risks from exposures to the chemicals of potential
concern at Torch Lake OU III for current and future populations are
summarized in Table 6.
Cancer risks which exceeded 1 X 10-6 for OU III are primarily
attributed to the ingestion of tailings by current or future adult
or child residents at all of the OU III locations. Estimated
excess cancer risks for current populations range from 3 X 10~ to
9 X 10~. Cancer risks exceed 1 X 10-6 for current residents at
Isle-Royale, Gross Point, and Lake Superior shore!ihe, for current
workers at Isle-Royale and Quincy Smelter, and vf$ftors (adult and
child) to Boston Pond and North entry of Lake superior. The
estimated risks for future residents range from 1 X 10.5 to 2 X 10~.
Cancer risks exceed 1 X 10-6 for hypothetical future residents
(adults and children) at all areas evaluated, however, only one
location, Michigan Smelter, presents an unacceptable cancer risk (2
X 10~). Chemicals contributing to these risks are mainly arsenic
and beryllium via ingestion of contaminated tailing and slag.
Inhalation of air-borne chromium contaminated materials also
contributes to the risk in those areas where this pathway was
evaluated. .
Estimated cancer risks to workers range from 2 X 10.7 to 1 X 10.5 and
for scavengers and visitors, risks range from 3 X 104 to 8 X 10-6.
OU III Non-Cancer Risks
Ingestion of tailings by current or future child residents poses
most of the potential non-cancer risks. Subchronic hazard indices
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27
calculated for the OU III exposure scenarios are summarized in
Table 6.
Subchronic health hazards (hazard indices greater than 1.0) were
calculated for current child residents at locations 7, 9, 10, 11,
and 12 and for future child residents at all other areas. These
risks are due principally to ingestion of tailings or slag
containing antimony, arsenic, copper and vanadium. Copper is the
most pronounced contaminant contributing to these hazard indices,
with hazard quotients greater than 1.0 for current child residents
at location 12 and for future child residents at locations 1, 3, 4,
5, 6, and 8. Arsenic has an HQ of 2.0 for a future resident child
at location 5 and antimony has an HQ of 5.0 for a future resident
child at location 6.
The only calculated chronic hazard index which exceeds 1.0 is for
future adult residents at location 6. The chemicals contributing
to this hazard index include antimony, copper and chromi~m,
although no single chemical contributed an HQ greater than 1.0.
au III National Park scenario
Because location 6 (Quincy Smelter area) is a part of the Quincy
Mining Company Historic District which is proposed for inclusion in
the National Historical Park, an exposure pathway was formulated to
investigate the potential risks to future populations who might be
exposed to the slag pile deposited at the Quincy smelting area if
this area were developed as a National Historical Park.
The potentially exposed populations at a national historical park
are visitors to the park (adults and children) and workers at the
site, including guides, caretakers and administrative personnel.
Considering the location of the site and the proposed development
of the Quincy smelting works, local residents may visit the park
with their children for picnicking and/or other recreational
activities.
Of the several types of workers at the site, the caretaker is
likely to have the greater exposure.. This individual is assumed to
work outdoors during the five months of the year without snow cover
and indoors during the remaining months. He is assumed to engage
in activities (cleaning, building maintenance, etc.) which involve
direct or indirect contact with tailings.
The estimated cancer risks for visitors to the Quincy Smelting area
are 3 X 10~ for both adults and children and the risk to workers is
2 X 10~. Arsenic is the major contributor to these risks. Hazard
index (HI) values (subchronic an chronic) calculated for all
populations are less than 1.0, indicating that noncarcinogenic
health effects are not of concern.
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28
Depending on the boundary line of the Calumet Historic Dist::ct,
location 1 (Calumet Lake tailings) would be a part of the proposed
National Historic Park. It is estimated that the cancer risk from
the tailings located in Calumet Lake, if developed as a National
Historic Park in the future, is less ~~an 1 X 10~ and non-cancer
risk is less than 1.0. This estimation is based on the
extrapolation from the risk data for a current exposure scenario.
However, the release of tailing materials from this location to the
lake would continue.
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Table 4
Toxicity Values for Contaminants of Potential Concern
Operable Units I and III - Torch Lake
Contaminants Oral Inhalation
Inorllanics RIDs RIDe SF . R!lli RIDe SF
Aluminum NA NA NA NA NA NA
Antimony 4.0 x 1O~ 4.0 x 10~ NA NA NA NA
Arsenic 1.0 x 10') 3,0 x 10~ 1.75 NA NA 15
Barium 5.0 x 10.2 7.0x 10.2 NA 1.0 x 10') 1.0 x 10~ NA
Beryllium 5.0 x 10') 5.0 x 10') 4.3 NA NA 8.4
Boron 9.0 x 10.2 9.0 X 10.2 NA NA NA NA
Chromium 2.0 x 10.2 5.0 X 10') NA 5.7 x 10" 5.7 X 10.7 42
Cobalt NA NA NA NA NA NA
Copper 4.0 x 10.2 4.0 X 10.2 NA NA NA NA
Lead NA NA NA NA NA NA
Manganese 5.0 x 10" 0.2 NA 1.1 x 10~ 1.1 x 10~ NA
Mercury 3,0 x 1O~ 3.0 x 1O~ NA 8.6 x 1O.j 8.6 x 1O.j NA
Nickel 2.0 x 10.2 2.0 X 10.2 NA NA NA 8.4 x 10"
Silver 3.0 x 10') 3.0 x 10') NA NA NA NA
Titanium NA NA NA NA NA NA
Vanadium 7.0 x 10') 7.0 x 10') NA NA NA NA
Qrnnics
Acenaphtbylenel NA NA NA NA NA NA
Benzol. a)pyrene NA NA 11.5 NA NA 6.1
Benzo(g.h.i)perylene NA NA NA NA NA NA
Benzol. a)anthracene" NA NA NA NA NA NA
BenzoI.b )fluoranthene1': NA NA NA NA NA NA
Benzo(k)fluoranthene:': NA NA NA NA NA NA
Chrysenel': NA NA NA NA NA NA
DibeDZD(a.h)anthracene= NA NA NA NA NA NA
bis(2-Ethylhexyl)phthalate 2.0 x 10'2 2.0 X 10.2 1.4 x 10': NA NA NA
Fluoranthe.ne 4.0 x 10.1 4.0 X 10'2 NA NA NA NA
Indeno( 1.2.3-cd)pyrene NA NA NA NA NA NA
2-Methylnaphthalenel NA NA NA NA NA NA
Naphthalene 4.0 x 10,1 4.0 X 10'1 NA NA NA NA
Phenanthrene I NA NA NA NA NA NA
Pyrene 3.0 x 10.1 3.0 X 10'2 NA NA NA NA
Toxicity Values: RIDs-Subcbronic Reference Dose (mglkg-day)
RfDc-chronic.Reference Dose I.mglkg-day)
SF- Slope Factor (mglkg-day).1
NA- No value available
1: Noncarcinogenic effects of this PAH evaluated using the RID for napthalene.
2: Carcinogenic effects of this PAH evaluated Using the SF for benz.o(a)pyrene.
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Table 5
Sumrmu:y of Cancer and Non-Cancer Subchronic ltisk
- Operable Unit I - Torch Lake
Exposure Pathway Cancer Risk Non-Cancer Risk
(Hazard Index)
Current Resident - -
Lake Linden (Inhalation) 3 x 1007 0.03
HubbeUrramaraclc City (Inhalation) 2 x 1007 0.01
Mason «Inhalation) 1 x 1
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Table 6
Summary of Cancer and Non-Cancer Subchronic Risk
Operable Unit III - Torch Lake
Exposure Pathway Cancer Risk Non-Cancer Risk
(Hazard Index)
Current Resident
Isle-Royale (location 7) 6 x 10,5 2.0.
Grosse-Point (location 9) 3 x 10,5 2.0.
Grosse-Point (location 10) 4 x 10,5 2.0.
Redridge (location 11) 9 x 10,5 2.0.
Freda (location 12) 3 x 10.5 3.0
Future Resident
Calumet Lake (location 1) 3 x 10'5 4.0
Calumet Poor Rock (location 2) 6 x 10'.1 2.0'
Boston Pond (location 3) 3 X 10,5 3.0
North Entry (location 4) 1 x 10"" 3.0
Michigan Smelter (location S) 2 x 10-4 5.0
Quincy Smelter (location 6) I x 10"" 10
Dollar Bay (location 8) I x 1~ 7.0
~
Calumet Poor Rock (location 2) 2 x UtI 0.005
Quincy Smelter (location 6) 9 x 10'1 0.9
Isle-Royale (location 7) 1 x 10'.1 NA
Dollar Bay (location 8) 8 x Ht' 0.5
Teenalle Scaven2er
Calumet Lake (location 1) 3 x 10" 0.02
Michigan Smeller (location S) 2 x 10.1 0.03
Quincy Smelter (location 6) 1 x 10" 0.06
Dollar Bay (location 8) 1 x Ut' 0.04
National Parte Scenario
Quincy Smelter (location 6) 2 x 10'.1 0.5
NA: Value Dot Available
. : Although Hazard Index exceeds 1.0. no individual Hazard Quotient ~xceeds 1.0.
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32
5.
Ecological Assessment
As part of the Baseline Risk Assessment, an environmental
evaluation, or ecological assessment, was conducted. The
Ecological Assessment identified terrestrial, wetland and aquatic
environments as potentially affected by the tailings in and around
the lakes.
(a) Adverse Effects in the Terrestrial Environment
Although well established and healthy plant communities exist in
areas surrounding tailing depos.its, most of the tailings remain
barren. pioneer vegetation is conspicuously absent except in
localized, isolated patches where streams flow through tailings,
along wooded edges of deposits, and in depressions where moisture
and organic matter accumulate. Plant survival and growth on
tailings are impaired by a combination of chemical and non-chemical
stresses, including poor water retention, extreme temperature
fluctuation, low organic content, and presence of toxic substances.
Studies have shown that high levels of copper inhibit vascular.
development in some plants (Strieleman 1979).
six species of plants classified as State threatened or of special
concern have been recorded in the vicinity of tailings deposits.
Several are shoreline species or have habitat requirements which
increase the likelihood that the species may be exposed to tailing
deposits. Populations of these species have not been investigated
to determine whether adverse effects from exposure to tailings are
occurring or tailings deposits have destroyed their habitat in the
study area.
Animal populations are likely to avoid tailing deposits for many of
the same reasons that the tailings have not been colonized by
plants. In addition, tai~ings lack food and cover required for
establishment of ecologically or recreationally important wildlife
populations. .
Cb) Adverse Effects in Wetlands
Deposition of tailings in surface waters is likely to have
destroyed existing wetlands in a number of areas, including Boston
Pond and along the western shore of Torch Lake. Wetlands are
generally absent along Torch Lake shores where the most significant
deposition of tailings took place, except where streams flow into
the lake.
Failure of wetlands to develop on tailing deposits in Torch Lake is
a serious problem. Large areas of the Torch Lake shoreline where
water is sufficiently shallow and suitable for growth of wetland
plants are devoid of wetland communities. The reasons for failure
of wetland vegetation to become established along shoreline areas
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33
of Torch Lake have not been investigated, but substrate and surface
water toxicity are likely to be involved. Ionic copper is likely
to be the toxic factor.
The loss of wetland habitat in Torch Lake is likely to
number of migratory and residential animal populations
this type of habitat for resting, feeding, and breeding
locations.
impact a
that use
at other
(c) Adverse Effects in Aquatic Environments
Severe degradation of benthic communities is the most significant
impact associated with tailing deposits and contaminated sediments
in Torch Lake and other surface waters at the site. The benthic
community is an integral part of the base of a complex food web in
lakes. A severely impacted benthic community would impact the
entire food web. Data is available to indicate that most of Torch
Lake, the northern 6 miles of the Portage Lake Shipping Canal and
nearshore areas of Lake superior between Redridge and the North
Entry suffer these adverse effects (Charters 1991, Leddy 1984,
Malueg et ale 1984b). Field and laboratory studies indicate that
toxicity due primarily to elevated copper concentrations in
sediments is responsible for observed environmental degradation.
Very few locations where sediment was sampled in Torch Lake have
sediment copper concentrations that are below laboratory estimates
of the LC,o (400 to 630 mqlJeq) for Hvalella exposed to copper in
contaminated sediment. These include three areas farthest removed
from the tailing deposits: in the mouth of the Trap Rock River;
near the mouth of the Trap Rock River; and in the south-central
area of the lake near the entrance to drainage into Portage Lake.
Extremely high concentrations of arsenic and lead in submerged
tailings near Hubbell are likely to enhance copper toxicity, so
this area represents the greatest risk to aquatic life in Torch
Lake. All other areas of the lake where tailings have been
deposited are likely to be too toxic for development of pollution
intolerant benthic organisms.
All measurements of copper concentrations in samples from tailings
at Boston Pond exceed the LC,o. Therefore, major reduction of
benthic populations is expected at that location".
other metals in tailings and contaminated sediment are likely to
contribute to aquatic impacts in the study area. A series of
benchmark sediment concentrations have been developed for
evaluating biological effects of sediment. contamination by the
National Oceanic and Atmospheric Administration from data collected
for the National Status and Trends Program. One of these, the
Effects Range-Low (ER-L) is the lower ten percentile concentration
of the rancje over" which adverse effects have been observed at
contaminated sites. A comparison of ER-Ls to Torch Lake sediment
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34
concentrations indicates that most other metals are present at
levels that have the potential to contribute to adverse biological
effec~s in the Torch Lake ecosystem. This is not the case in Lake
Gogebic, 60 miles to the southwest.
The extremely limited benthic communities in Torch Lake suggest the
lake is below its full potential for supporting fish production.
Plankton are assumed to provide a food base for a portion of the
fish community in Torch and portage Lakes. Data on plankton
communities is too limited to estimate the productive potential
provided by this portion of the aquatic ecosystem in the study
area.
A major issue. in evaluating adverse effects of contaminants on fish
communi ties is reproduction of fish populations in Torch and
Portage Lakes. Adult fish are likely to migrate extensively
throughout the waterway. Data on fish migration and reproduction
in the waterway are not available, so the relative contributions' of
exogenous and endogenous production cannot be evaluated. Hatching
duration in perch eggs from Torch Lake are significantly longer
than the hatching duration in eggs from a control lake. However,
yellow perch are well represented in recent samples from Torch and
Portage Lakes.
Fish may be reproducing along the eastern and southern shores of
Torch Lake and iniits tributaries. Areas where tailings deposits
occur are unlikely to provide suitable habitat for breeding. Given
the extensive are~ covered by tailings, it appears that Torch Lake
now contains les~'suitable habitat for fish spawning than existed
before tailings were deposited in the lake.
Tumors and accumulation of toxic chemicals are two adverse effects
in fish populations attributed in the past to contamination in the
lakes. Liver tu~rs in fish, once an obvious problem in the study
area, were not observed in the most recent samples from Torch and
Portage Lakes. 'Other types of tumors were not included in the
examinations. Mercury, PCBs and 4-4'-DDE have been observed, at
trace levels in northern pike, smallmouth bass and walleye in
recent samples from Torch Lake. These chemicals are likely to be
associated with sources other than contaminated tailings.
Copper concentrations in surface water in Torch Lake generally
exceed Federal acute and chronic ambient water quality criteria for
protection of aquatic life. Aluminum, cadmium, iron, lead and
mercury also exceed criteria for protection of aquatic life at one
or more sampling lQca.tions. However, fish bioassays using the
fathead minnow do not indicate that surface water in Torch Lake is
toxic to fish. 'This lack of ~oxicity in bioassays may be due to
complexation of metals by dissolved humic substances.
Study results indicate that the short-term reproductive biology of
bald eagles and gulls nesting within the site ecosystem appears
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35
normal. The effect of copper on long term productivity is unclear.
Long-term productivity data on the portage Lake eagle nest
indicated a poor reproductive history. However, poor productivity
in eagles nesting near the Great Lakes has been associated with
organochlorine and PCB contamination, making interpretation of the
effects of other contaminants such as copper more difficult.
Based on the analytical chemistry results for copper, there does
not appear to be an adverse reproductive effect on gulls or eagles
that can be associated with exposure to Torch Lake copper
concentrations.
U. S. EPA has determined that actual or threatened releases of
hazardous substances from this site, if not addressed by
implementing the remedy selected in this ROD, may present an
imminent and substantial endangerment to public health, welfare, or
the environment.
VII.
DESCRIPTION OF REMEDIAL ALTERNATIVES
Based on the results of the Rls and risk assessments for OUs I and
III, a Feasibility Study was conducted to identify and evaluate a
variety of alternatives for protecting human health and the
environment from the contamination associated with tailings and
slag piles/beach at the site. After identifying and screening
potential remedial technologies for the site, two alternatives for
the tailing piles and four alternatives for the slag piles/beach
were selected for further evaluation. The selection of these six
alternatives from various remedial technologies was based on the
screening process considering the remediation goal, state-of art
technology, technical impracticability, cost, volume of tailings to
be addressed, contaminant levels, and the merit of the technology.
Each of the alternatives is evaluated using a set of nine criteria
that reflect the goals of the superfund program and are used by
U.S. EPA to compare the merits of each alternative. These criteria
are explained in section VIII.
Four locations in OU III are not being considered for further
evaluation of alternatives at this time. These locations are
Location 2, Calumet poor Rock; Location 4, the North Entry to Lake
superior; and Locations 11 and 12 along the Lake superior shoreline
of the Keweenaw Peninsula. Location 2 is a site of disturbed but
unprocessed rock piles which present no risk, and do not contain
the properties of tailings or slag materials. Locations 4, 11, and
12 are along the Lake superior shore where pounding waves and water
currents will likely retard or destroy any remedial action. As a
result, U.S. EPA currently believes it to be technically
impracticable .to implement the chosen remedy at these locations.
However, a portion of the tailings at locations 4 and 12 may be
sufficiently unaffected by the lake to effectively implement the
soil cover and vegetation remedy. This possibility will be
explored during Remedial Design. The poor rock and slag materials
located upstream of Trap Rock river are also excluded because these
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36
materials are unprocessed rocks.
Descriptions of the six alternatives considered by u.s. EPA are
provided below, including costs, estimated in terms of capital cost
and annual operation and maintenance cost. Together these two
dollar amounts are converted to net present worth. U.S. EPA I S
evaluation of each remedial alternative using the evaluation
criteria is summarized in Section VIII.
The alternatives considered for tailing piles in OUs I and III are:
Alternative '1'1:
No Action.
Alternative '1'2:
soil cover with Vegetation.
The alternatives considered for slag piles/beach in OUs I and III
are:
Alternative 81:
No Action.
Alternative 82:
Fencing.
Soil cover with vegetation for slag pile/beach
located in Hubbell.
Alternative 83:
Alternative 841
Excavation and Off-site Disposal.
A Description of each of these alternatives follows:
Alternative Tl:
No Action
u.s. EPA requires consideration of a no-action alternative to serve
as a basis against which other remedial alternatives can be
compared. The no action alternative involves no treatment. or
containment of the contaminants present in the tailings.
Therefore, the potential risk to human health at a few of the
tailing piles in OU III through the inhalation and ingestion
pathways will remain the same. The environmental impact from the
tailings will also remain the same.
Alternative T2:
Soil Cover with vegetation
Alternative T2 consists of installing a soil cover over the exposed
tailings, and then vegetating the cover by seeding with appropriate
native plant species. A maintenance program including mulching,
fertilizing, and irrigating would be also implemented. Deed
restrictions would be sought to control the use of tailing piles,so
that tailings will not be left, long term, in a state that w~ll
expose humans and animals to contaminants. Before the soil cover
is installed, debris such as wood, empty drums, and other garbage
in the tailing piles would be removed for off-site disp~sal in
order to effectively implement the soil cover. with vegetat10n.
I!
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37
The total area of tailing piles to be addressed under this
alternative would be approximately 671 acres; 442 acres for OU I
tailings and 229 acres for OU III tailings.
The costs for Alternative T2 for OUs I and III would be:
OU I
OU III
Total
Capital Cost: $3,297,500
operation and Maintenance: $ 50,000
Present Net Worth: $3,146,000
$2,890,000
$ 58,000
$2,868,000
$6,187,500
$ 108,000
$6,014,000
The implementation time for this alternativ~ would be 5 years.
operation and Maintenance includes 10 years of a maintenance
program of planted vegetation such as mulching, fertilizing and
irrigating.
(The total present net worth is lower than the capital cost because
the placement of soil cover is estimated to take 5 years. The
interest accrued over five years would cover the increased cost) .
Alternative SI:
No Action
The no action alternative, SI, for slag piles/beach involves no
treatment or containment of the slag piles/beach. Therefore, the
potential for these contaminants at a few of the slag piles in OU
III to be inges~Q or to be released to air and inhaled by humans
will continue to exist. The environmental impact from the slag
pile should remaih the same.
. ,r
Alternative S2:
Fencing
This alternative consists of a 4-foot high fence around the slag
piles/beach located in OUs I and III, three strands of barbed wire,
and warning sig~to restrict access.
The perimeter of slag material to be fenced would be approximately
7,000 linear feet, 4,000 linear feet for OU I slag and 3,000 linear
feet for OU III slag.
The costs for Alternative 52 are:
'ou I
ou III
Total
capital Cost:
operation and Maintenance:
Present Net Worth:
$ 30,000
$ 300
$ 34,000
$ 22,000
$ 300
$ 26,100
$ 52,000
$ 600
$ 60,100
The implementation time for this alternative would be 1 month.
Alternative S3:
soil Cover with vegetation (Slag pi~e/beach in
HUbbell)
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- 38
Alternative S3 consists of installing a soil cover over the exposed
slag pile/beach in Hubbell (aU I), and then vegetating the cover by
seeding with appropriate native plant species. The maintenance
program including mUlching, fertilizing, and irrigating would be
also implemented. Deed restrictions would be sought to prevent-the
use of slag pile/beach that will expose humans and animals to
contaminants.
This alternative only applies to the slag piles/beach at Hubbell
(aU I), and does not apply to the slag pile at the Quincy Smelter
(Location 6, au III) for the following reasons:
.
The slag pile at Hubbell (aU I) is located in the middle of a
residential area and therefore poses a greater risk of
exposure to the residents living near the slag pile/beach at
Hubbell than the Quincy slag pile which is located in an
industrial area.
.
The Hubbell slag pile (aU I) is amenable to the installation
of soil cover and vegetation.
.
The Quincy slag pile (aU III) is very steep and requires
regrading before an effective soil cover can be installed.
The capital cost for implementing this alternative is $105,000 and
operation and maintenance .cost is anticipated to be $1,000.
Present net worth is $112,400. The implementation time for this
alternative would be 3 months.
Alternative S4:
Excavation for off-site Disposal
This alternative consists of excavation of the slag piles/beach in
aus I and III, transportation of the excavated material, and
disposal of the material in an off-site landfill.
Implementing this alternative should allow for unrestricted future
development of the property on which the slag piles/beach are
presently situated if it is determined that no institutional
controls are required after slag removal.
The volume of slag materials to be addressed under this alternative
would be approximately 236,000 cubic yards, 94,000 cubic yards for
au I slag and 141,000 cubic yards for OU III slag.
The costs for Alternative S4 for aus I and III would be:
au I
au III
Total
capital Cost: $4,463,000
operation and Maintenance: $ 0
Present Net Worth: $4,463,000
$6,685,000
$ 0
$6,685,000
$11,148,000
$ 0
$11,148,000
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39
The implementation time for this aiternative would be 1 year.
VIII.
SUMMARY OF THE COMPARATIVE ANALYSIS OF ALTERNATIVES
A detailed analysis was performed on the six alternatives using the
nine evaluation criteria in order to select control remedies for
tailings and slag piles/beach. The following is a summary of the
comparison of each alternative's strength and weakness with respect
to the nine evaluation criteria. These nine criteria are:
1)
2)
3 )
t1 )'
5)
6)
7)
8)
9)
Overall Protection of Human Health and the
compliance with ApplicaDle or Relevant
Requirements (ARAR's)
Lonq-Term Effectiveness and Permanence
Reduction of Toxicity, MODility, or Volume
Short-Term Effectiveness
ImplementaDility
Cost
state Acceptance
community Acceptance
Environment
and Appropriate
throuqh Treatment
1.
Overall Protection of Human Health and the Environment
Alternative Tl represents the no action alternative for the
tailings. This alternative does not satisfy the requirement for
overall protection of human health and the environment. Non-cancer
risks at OU III Locations 1, 3 through 6, 8, and 12 were higher
than acceptable levels due principally to copper and, at Location
5, arsenic. Alternative Tl will not mitiqate these' risks.
Further, Alternative Tl will not address environmental harm.
Severe deqradation of benthic communities and absence of wetlands
in shallow areas are the most significant impacts associated with
tailing deposits and contaminated sediments in Torch Lake and other
surface waters in the area. Data is available to indicate that
most of Torch Lake and the northern 6 miles of the Portage Lake
Shipping Canal suffer these adverse affects. Reduction of'
productivity in fish populations is a possible secondary result of
these impacts. Under a no-action alternative, degradation of the
lake environment could continue. This may preclude the re-
establishment of a more typical lake environment found in northern
Michigan lakes.
Alternative T2 is protective of human health and the environment in
those few areas where the risk to human health is unacceptable.
Soil cover over exposed tailings will reduce or eliminate the
potential risks due to the inhalation and ingestion pathways.
Vegetation will control erosion of the soil cover. Alternative T2
will also minimize surface water run-off from the tailings and will
reduce potential transport of contaminants into the lake. Thus,'
installing soil cover and vegetation would benefit the aquatic
environment by substantially reducing the potential for contaminant
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40
transport via surf~=e water erosion of and air bc:-ne from tailings
into the lake. The establishment of healthy "egetation will
facilitate potential development of animal habitat by providing
forage and cover for terrestrial animals.
Alternative Sl represents the no action alternative for the slag
piles/beach. This alternative is not protective of human health
for au I slag. contaminants would continue to be transported off-
site by wind dispersion. The au I slag piles/beach do not promote
vegetation and could be detrimental to establishment of habitat in
the future. The risk scenario for au III slag is different as it
is located in an industrial area. Under the National Historic Park
scenario in which a national historic park"will be developed, which
includes Quincy Smelter (aU III, Location 6), in the future, risks
to human health for potential visitors and workers are in the
acceptable range. In addition, because the slag at this location
is in a massive, vitrified form, it is not ':hought to be a
contaminant source to the lake.
Alternative S2 includes fencing the slag piles/beach. Although
fencing does not treat or contain contaminants, it reduces the risk
of exposure to contaminants by limiting the opportunity for
ingestion. currently, unrestricted access permits certain areas of
the slag piles/beach to be used for unauthorized dumping or other
activities. Fencing will deter such activities and reduce
associated exposure scenarios. In this way, Alternative S2 could
be sufficiently protective of human health. However, contaminants
would continue to be carried off-site by wind dispersion and the
slag will not promote vegetation.
Alternative S3 will achieve the established remedial objectives
because exposure to contaminants will be eliminated since the
p~inciple source of threat would be contained.
Alternative S4 will achieve the established remedial objectives and
will protect human health because contaminants will be removed from
the site. Risk associated with exposure to contaminants from the
slag will be eliminated because the source of the threat will be
removed from the site.
2.
ComDliance with ARARs
A detailed evaluation of ARARs pertaining to each tailing and slag
pile/beach alternative is presented in the FS.
Alternative T2 complies with pertinent ARARs specific to this
alternative. The Michigan Environmental Response Act 307 is an
applicable requirement for this site. u.S. EPA has determined that
this alternative complies with an Act 307 Type "c" cleanup. Under
the MDNR's reading of Act 307, this ROD is to be considered an Act
307 interim remedy, as allowed by R 299.5509. U.S. EPA considers
this remedy to be a final remedy for Operable Units I and III.
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41
The Clean Air Act (CAA), 40 CFR Parts 50, 51 and Michigan Air
Pollution Act 348 are relevant and appropriate because air-borne
tailings dust generated during construction of the site cover could
migrate through the air pathway which could affec~ human residents
as well as environmental recipients of the contaminants including
animals (including endangered species) and the lakes. During
implementation, air sampling will be performed to monitor potential
release of contaminants into the air. In addition, dust control
measures will be employed to assure compliance with these ARARs.
The Protection of Wetlands Act and Michigan Act 203 (1974) are
relevant and appropriate because of wetlands in OUs I and III which
may be affected by Alternative T2. To comply with this ARAR, care
w~ll be taken to ensure that wetland areas are clearly delineated
and protected from soil cover installation at all locations within
OU I and OU III.
Alternative T2 will comply with the requirements of Michigan Act
347 (1972), soil Erosion and Sedimen~ation control Act.
Alternative 52 complies with the Federal ARARs. The state of
Michigan has indicated that it believes that Alternative S2 does
not meet Michigan Act 245, Act 348, or. Act 307 Type C cleanup
criteria triggered by this alternative. Fencing cannot prevent
migration of contaminants via wind dispersion, groundwater
movement, and/or surface water runoff. If this alternative were
selected for slag materials, then a waiver of ARARs would
potentially be needed.
Alternative 53 complies with all listed ARARs for Alternative T2.
Alternative S4 complies with all applicable ARARs listed for
Alternative T2 except that the Quincy Smelter historic area could
be impaired.
3.
Lona-Term Effectiveness and Permanence
The evaluation of alternatives under this criterion address the
risk remaining at the Torch Lake site at the conclusion of remedial
activities and the ability of alternatives to maintain reliable
protection of human health and the environment over time.
Alternative Tl provides no long-term protection and would allow the
current conditions to remain at the Torch Lake site. Alternative
T2 on the other hand,. is effective because the contaminants would
be contained, minimizing tailing erosion into the ~ake and
enhancing the development of terrestrial habitat. Residual risk is
minimal as long as the integrity of the soil cover is maintained.
Alternatives 51 provides no long-term effectiveness and would
result in the elevated risk levels that currently exist where the
slag piles/beach are located. Alternative 52 provides some degree
of effectiveness because fencing will reduce the risk of exposure
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42
to contaminants by ingestion. Alternative S3 will provide long-
term effectiveness because it would reduce the risks of
environmental harm and would reduce inhalation and ingestion of
material from a few of the contaminated piles. Alternative S4 will
provide long-term effectiveness because the source of contamination
will be'permanently removed from the site.
4.
Reduction of Toxicitv. Mobilitv and Volume throuqh treatment
This criterion addresses the statutory preference for selecting
remedial actions which use treatment technologies that permanently
and significantly reduce toxicity, mobility or volume of
contaminants. Because of the large area covered by the
contaminants and the volume of material to be treated, potential
remedial actions involving treatment were determined to be
impractical for the Torch Lake site. consequently, none of the
proposed alternatives involve treatment of contaminants.
Alternative T1 does not reduce toxicity, mobility or volume of
contaminants on-site. Alternative T2 also does not reduce toxicity
or volume of the contaminants through treatment. However, this
alternative reduces the release of the contaminants through the
air, groundwater and lakes.
Alternatives 51, S2, 53, and 54 do not reduce toxicity, mobility or
volume of contaminants through treatment. However, Al ternati ve 54
eliminates the toxicity, mobility, or volume of contaminants with
respect to the site via off-site shipment of slag to a landfill.
Alternative 53 reduces the mobility of contaminants by reducing the
potential for redistribution via wind, surface water runoff
(erosion), or by water infiltration.
5.
Short-Term Effectiveness
This criterion addresses the effects of the alternatives on human
health and the environment during. the construction and
implementation phases. The short-term effectiveness period extends
until the remedial response objectives are met. .
This criterion is not applicable to Alternative T1 because no
action will be taken. Alternative T2 will potentially generate
short-term particulate emissions and noise. Dust control measures
and development of health and safety plans are proposed as part of
this alternative to minimize these hazards. Incidental noise
pollution will be minimized by proper scheduling of work hou~s.
Alternative 51 poses no short-term hazards. Alternative 52 would
need to include health and safety measures to protect workers
installing the fence from exposure to contaminants. Alternatives
53 and S4 would need to include a health and safety plan, as well
as dust control measures to control fugitive emissions. For
Alternative S3, the soil cover can be placed within 1 year.
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43
6.
ImDlementabilitv
This criterion addresses the technical and administrative
feasibility of implementing an alternative, and the availability of
various services and materials required for its implementation.
Al ternati ve T1 involves no action and thus, no implementation.
Alternative T2 can be readily implemented, except in those areas
wherein u.s. EPA believes implementation to be technically
impracticable, because installing a 'vegetated soil cover is an
established technology and competitive bids can be obtained from
many commercial vendors.
Alternative Sl requires no implementation'because it represents the
no action alternative. Alternatives 52 and 53 can both be
implemented. Alternatives 53 and 54 are more difficult to
implement than Alternative 52 because they require more detailed
planning. Alternative 53 may be more efficiently implemented and
cost-effective if Alternative T2 is also implemented. Because
large quantities of slag have to be transported off-site for
Alternative 54, landfill cells will have to be prepared in advance
to receive the material.
7.
~
For Alternative T2, a modified approach was adopted for present
worth analysis. This alternative will require 5 years for
implementation. Since contractors performing the remediation will
require payment as services are rendered, :the total capital
expenditure was assumed to be received in five equal installments.
The costs incurred in the second, third, fourth, and fifth years
are adjusted to the base year by applying the appropriate present
worth factor. Because the capital expenditure is distributed over
5 years, this approach for calculating present worth will result in
a slightly lower present worth cost than would be obtained by
assuming that all of the capital cost will be incurred at the end
of 5 years. The O&M costs for Alternative T2 is expected to be
incurred for only 10 years after which a full vegetative cover is
anticipated to be established.
Alternative S4 is the most expensive and Alternative 51 is the
least expensive.
See section VII for detailed cost information of each alternative.
8.
5tate Accectance
The Michigan Department of Natural Resources (MDNR) concurs with
the selected remedy.
9.
communitv AcceDtance
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44
The specific comments received and U.S. EPA's response are outlined
in the attached Responsiveness Summary.
IX.
THE SELECTED REMEDY
As provided in CERCLA and the NCP, and based upon the evaluation of
the RI/FS and the nine criteria, the U.s. EPA, in consultation with
the MDNR, has selected Alternative T2 for tailing piles in OU I and
III, Alternative S3 for the Hubbell slag pile/beach and certain
slag piles in OU I, and Alternative Sl for Quincy Smelter slag pile
in OU III as the remedial action at the Torch Lake site, Operable
Units I and III.
These alternatives were selected for tailings and slag piles/beach
located in OUs I and III of the Site based on the cancer risk to
current and future residents from inhaling and ingesting certain
tailings and slag piles/beach, the non-cancer risk from taili~gs
and slag materials at certain tailing/slag piles in OU III, the
adverse impact of the tailings on Torch Lake and other water
bodies, the adverse impact of the tailing piles on the natural
habitat surrounding Torch Lake, including the loss of wetlands, and
the location of these contaminants in a Great Lake IIArea of
Concernll. In addition, the selected alternatives provide the best
balance of the nine evaluation criteria.
The major components 9f selected remedy include the following:
*
Deed restrictions would be sought to control the use of
tailing piles and slag piles/beach so that tailings and/or
slag will not be left in a condition which will expose humans
and animals to contaminants or increase the potential for run-
off of cantaminants into the lake;
*
Removal of debris such as .wood, empty drums, and other
garbage in the tailing piles for off-site disposal in order
to effectively implement the soil cover with vegetation;
Soil cover with vegetation over OU I tailings in Lake Linden
(124 acres), Hubbell/Tamarack city (121 acres), and Mason (197
acres). OU I tailings was estimated as 442 acres;
*
*
soil cover with vegetation over OU III tailings in Calumet
Lake (location 2, 2 acres), Boston Pond (location 3, 65
acres), Michigan Smelter (location 5, 23 acres), Dollar Bay
slag pile (location 8, 28 acres), and Grosse-Point (location
9 and 10, 157 acres). OU III tailings were estimated as 229
acres;
*
soil cover with vegetation over OU I slag pile/beach in
Hubbell. OU I slag pile/beach was estimated as 9 acres;
., c.
*
The Isle-Royale tailings in OU III will be excluded from the
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45
area to be covered with soil and vegetation under this ROD as
follows:
The portion of Isle-Royale tailings which is being
developed as a sewage treatment plant will be excluded
from the area to be covered with soil and vegetation
under this ROD. The part of this area to be covered by
conventional sewage treatment tanks is approximately 12
acres. The remaining part, approximately 48 acres, will
be covered with soil and vegetation by the Portage Lake
Water and Sewage Authority as part of the sewage
treatment facility development plan. If this area is not
covered and vegetated within 5 years after the date that
the final Remedial Design is submitted, then this area
shall be subject to the requirements of this ROD. The
completed sewage treatment facility will achieve the
remedial objectives by reducing the release of
contaminants into the air;
The portion of the Isle-Royale tailings which is
designated to be developed as a residential area will be
excluded from the area to be covered with soil and
vegetation under this ROD. This area covers
approximately 90 acres. However, if this area is not
developed as a residential area within 5 years after the
date that the final Remedial Design is submitted, then
this area shall be subject to the requirements of this
ROD;
The portion of the ISle-Royale tailings which is
currently being used as source material to make cement
blocks and as a finished block storage area for the
superior Block company will be excluded from the area to
be covered with' soil and vegetation under this ROD. This
area is estimated to be 60 acres. It is determined th~t
the use of tailings as a storage area for cement blocks
would somewhat achieve the remedial objectives by
reducing the release of contaminants into the air.
However, if any portion of the area is no longer to be
used as a storage area, soil cover with vegetation must
be implemented pursuant to this ROD. The owner and/or
operator of superior Block Co. must use dust control
measures such as water spray during the operation of
mining and other activities in order to reduce the
release of dust into the air; ,
*
The area designated by Houghton county Road commission as
source material to spread on the road during winter to provide
traction for motor vehicles will be excluded from the area to
be covered with soil and vegetation. This area is located in
Grosse-Point and is estimated to be 46 acres. The tailing
pile presents no unacceptable risk to human health. While
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46
this area is being utilized, the following procedures must be
observed:
The area should be covered with enough soil to
prevent the release of tailings to the air and
lake;
Excavation should stop at seven (7) feet above the
water table. (defined as the average of seasonal
highs and lows over a two year period). This
portion must subsequently be covered with soil or
soil and vegetation;
Once the entire area is excavated to seven (7) feet
above the water table, it must be covered with soil
and vegetation pursuant to this ROD;
*
No action for the OU III slag pile located in the Quincy
Smelter area (location 6, approximately 25 acres), based on
the assumption that this area will be developed as part of a
National Historic Park. If this area is not developed as a
National Park in the future, deed restrictions will be sought
to prevent the development of residences in the slag pile
area;
The North Entry (location 4), Redridge (location 11) and Freda
( location 12) tailings are excluded from the area to be
covered under this ROD. Locations 4, 11, and 12 are along the
Lake Superior shore where pounding waves and water currents
will likely retard or destroy any remedial 'actions. As a
result, u.s. EPA currently believes it to be technically
impracticable to implement the chosen remedy at these
locations. However, the North Entry (location 4) and Freda
(location 12) tailings, approximately 46 acres, shall be
studied during Remedial Design. If U.S. EPA determines that
any portion of these two areas is sUfficiently unaffected by
Lake Superior wave activity such that it can be effectively
covered with soil and vegetated, then the unaffected area or
areas shall be subject to the requirements of this ROD.
Estimated costs for implementing the selected remedies, based on an
assumption of 442 acres of OU I tailings, 9 acres of OU I slag, and
290 acres of OU III tailings, are as follows:
*
CaDital Costs:
Operable Unit I: $3,402,000
Operable Unit III: $2,890,000
Annual Maintenance Costs:
Operable Unit
I : $51,000
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47
Operable unit III : $58,000
Present Net Horth:
Operable unit I : $3,258,000
Operable Unit III : $2,868,000
Total Present Net Worth:
Operable units I and III: $6,126,000
x.
STATUTORY DETERMINATIONS
The selected remedy must satisfy the requirements of Section 121 of
CERCLA to:
E.
protect human health and environment;
comply with ARARs:
Be cost-effective:
Utilize permanent solutions and alternate treatment or
resource recovery technologies to the maximum extent
practicable: and,
Satisfy the preference for treatment as a principle
element of the remedy or document in the ROD why the
preference for treatment was not satisfied.
A.
B.
C.
D.
The implementation of the selected remedy at the site satisfies the
requirements of CERCLA as detailed below:
A.
Protection of Human Health and the Environment
This selected remedy will provide adequate protection of human
health and the environment through soil cover with vegetation.
Risk posed by contaminants in the tailings and slag piles/beach in
OU I and in the few tailing/slag piles in OU III through direct
contact and air inhalation will be reduced and controlled by soil
cover and vegetation over tailings and slag pile/beach. The North
Entry (location 4) and Freda (location 12) tailings do present a
non-cancer health risk based on current (location 12) and future
(location 4) residential scenarios, however these areas are
excluded from the area to be covered under this ROD. Locations 4
and 12 are situated along the Lake superior shore where pounding
waves and water currents will likely retard or. destroy any remedial
actions. As a result, U. S. EPA currently bel ieves it to be
technically impracticable to implement the chosen remedy at these
locations. However, portions of locations 4 and 12 may be
sufficiently unaffected by wave activity such that soil coverage
and vegetation may be possible. Therefore, during Remedial Design,
location 4 and location 12 will be studied so as to determine
whether the residential scenario, and therefore remedial action
under this ROD, is appropriate for any portion of either area.
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48
Obviously, areas which are subject to violent wave action could not
be justifiably described as residential.
No unacceptable short-term risks will be caused by implementation
of the remedy. Standard safety programs, such as monitoring, 'and
use of pro~ective equipment, should mitigate any short-term risks.
Short-term risks include exposure of site workers and the community
to dust particles, and to noise nuisance during implementation of
the soil cover with vegetation. Ambient air monitoring would be
conducted and appropriate safety measures would be taken if
contaminants were emitted.
B.
ComDliance with ARARs
The selected Remedial Action for Operable units I and III of the
site will comply with all Federal and more stringent state
applicable or relevant and appropriate requirements.
u.s. EPA has determined that alternatives T2 and S3 comply with a
Michigan Environmental Response Act 307 Type "C" cleanup. Under
the MDNR's reading of Act 307, this ROD is to be considered an Act
307 interim remedy, as allowed by R 299.5509. U.S. EPA considers
this remedy to be a final remedy for Operable Units I and III.
During implementation of Alternatives T2 and S3, air sampling will
be performed to monitor potential release of contaminants into the
air and dust control measures will be employed to meet compliance
with ~AA and Mich~gan Air Pollution Act 348.
\
Alternatives T2 and S3 shall be designed and implemented not to
destroy, 10S8 or injure the wetlands located at the Site in order
to comply with Protection of Wetlands and Michigan Act 203.
The State has indicated that it believes the Michigan Solid Waste
Act 641 (1979) to be an ARAR for this ROD. U.S. EPA does not
concur with this assessment. First, U.S. EPA has determined that
Act 641 is not applicable. Secondly, even if Act 641 may be
relevant in that tailings and slag from copper mining may be
considered a solid waste from an industrial process, U.S. EPA has
, determined that Act 641 is not appropriate in that an Act 641 cap
is not well-suited to this site due to the size and situation of
the areas addressed by this ROD.
The following ARARs are associated with the selected remedy for
this site:
Chemical SDecific
.
Clean Air Act (CAA) 40 CFR 50.1-6,8,9,11 and 12.
.
Michigan Environmental Response act 307 (1982), MCL 299.601 R
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49
299.5101
.
Michigan Air Pollution control Act 348 (1965) Part 2,3,9 and
10
Action Specific
.
Clean Air Act (CAA) , 40 CFR Parts 50, 51
.
Federal Protection of Wetlands Act, 40 CFR 6, APP.A
.
MiChigan Act 203 (1974), wetland Protection Act
.
Michigan Shore land Protection and Management Act 245 (1970)
.
Michigan Act 347 (1972), Soil Erosion
Control Act, MCL 282.101 R 323.1701
and
Sedimentation
.
Michigan Act 348 (1965), Parts 2, 3, 9, and 10, Air Pollution
Act
Location Specific
.
Historic
preservation
CFR
Act,
40
.
Archaeological and
6.301(0)/16 USC 469
National Historic Preservation act, 40 CFR 6.301(b)/16 USC 470
.
Historic sites, Buildings and Antiquities Act, 40 CFR
6.301(a)/16 USC 461-467
Fish and Wilq.life Coordination Act, 40 CFR 6.302(g)/16 USC
1531-1566
.
.
Endangered Species Act, 50 CFR Parts 17 and 402/16 USC 1531-
1543
.
Protection of Wetlands, 40 CFR 6 (App. A)
.
Michigan Endangered species Act
R299.1021
203
(1974) ,
MCL 299.221
.
Michigan wetland
R281. 921
Protection Act
203
(1979) ,
MCL 281. 701
.
Michigan Shoreland Protection and Management act 245 (1970),
MCL 281. 641
.
Michigan Soil Erosion. and Sedimentation Control
(1972), MCL 282.101 R323.1701
act
347
The following requlations are identified as to be considered (TBC)
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50
for this ROD:
.
Occupational Safety and Health Act, 29 CFR 120
.
Michigan Act 154, Rule 3301
Safety and Health Act.
(1974),
Michigan Occupational
.
MCLA 257.722, Michigan Vehicle Code
C.
Cost-Effectiveness
Cost-effectiveness compares the effectiveness of an alternative in
- proportion to its cost of providing its environmental benefits.
The selected remedy is cost-effective because it provides a high
degree of overall effectiveness proportional to its costs. The
estimated cost of the selected remedy is comparable with the other
alternatives and assures a high degree of certainty that the remedy
will be effective in the long-term due to the significant reduction
of the risks due to the direct contact and air inhalation and of
the release of contaminants into the environment.
D.
utilization of Permanent Solutions and Alternative Treatment.
Technoloaies or Resource Recoverv Technoloaies to the Maximum
Extent Practicable
./~'~
The selected remedy does not involve treatment technologies because
any form of treatment for the tailings and slag piles/beach is not
practicable or CQst effective at this time. However, U.S. EPA
believes and the State of Michigan concurs that the selected remedy
represents the maximum extent to whtcn permanent solutions can be
utilized in a cost-effective manner:/fol:' the remedial action at the
Site. Soil cover with vegetation over tailings and slag pile/beach
located at the ~te will significantly reduce the risks posed
through direct contact and air inhalation. The selected remedy
would also reduce--the release of tailings into the lakes through
erosion, water infiltration, and air deposition. u.s. EPA has
determined that the selected remedy provides the best balance of
tradeoffs in terms of long-term effectiveness and permanence,
reduction of toxicity, mobility or volume through treatment, short-
term effectiveness, implementability, cost and State and community
acceptance.
E.
Preference for Treatment as a PrinciDal Element
The risks to human health and the environment associated with
Operable Units ,I and III of the site are presented by the
contaminated tailings and slag pile/beach.
Although treatment was not found to be practical, the selected
remedy addresses these risks by installing soil cover with
vegetation over contaminated 'tailings and slag pile/beach. The
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51
groundwater, surface water, sedimen~s, and associated biota at the
site will be addressed in an operable Unit II ROD.
XI.
DOCUMENTATION OF SIGNIFICANT CHANGES
After a careful review of the comments received from the public
during the public comment period and public meeting, U.S. EPA has
determined that the following areas should be excluded from the
area to be covered with soil and vegetation under this ROD:
*
The Isle-Royal tailings in OU III will be excluded as
follows:
The portion of Isle-Royale tailings in OU III which
is being developed as a sewage treatment plant.
The part of this area to be covered by conventional
sewage treatment tanks is approximately 12 acres.
The remaining part, approxima~ely 48 acres, will be
covered with soil and vegetation by the Portage
Lake Water and Sewage Authority as part of the
sewage. treatment facility development plan.
However, if this area is not covered and vegetated
within 5 years after the date that the final
Remedial Design is submitted, then this area shall
be subject to the requirements of this ROD;
The portion of the Isle-Royale tailings which is
designated as an area to be developed as a
residential area. This area covers approximately
90 acres. However, if this area is not developed
as a residential area within 5 years after the date
that the final Remedial Design is submitted, then
this area shall be subject to the requirements of
this ROD; .
The portion of Isle-Royale tailings in OU III which
is currently being used as source material to make
cement blocks and as a finished block storage area
for the superior Block Company. This area covers
approximately 60 acres. However, if any portion of
the area is no longer to be used as a storage and
source area, soil cover with vegetation must be
implemented pursuant to this ROD. The owner and/or
operator of superior Block Co. must use dust
control measures such as water spray during the
operation of mining and other activities in order
to reduce the release of dust into the air; and
*
The portion of the Grosse-Point tailings which is
currently being used by the Houghton County Road
commission as source material to spread on the road
during winter to provide traction for motor vehicles.
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52
This area covers approximately 46 acres. While this area
is being utilized, the following procedures must be
observed:
The area should be' covered with enough soil to
prevent the release of tailings to the air and
lake;
Excavation should stop at seven (7) feet above the
water table (defined as the average of seasonal
highs and lows over a two year period). This
portion must subsequently be covered with soil or
soil and vegetation;
Once the entire area is excavated to seven (7) feet
above the water table, it must be covered with soil
and vegetation pursuant to this ROD
U.S. EPA has determined that the completed sewage treatment
facility would achieve the remedial objectives by covering the
tailings. The use of tailings as a cement block storage area would
also somewhat achieve the remedial objectives by reducing the
release of contaminants into the air. Therefore; U.S. EPA has
determined to exclude the Isle-Royale tailings (as described above)
from the area to be covered with soil and vegetation under this
ROD. However, .~f the area is no longer used as a cement block
storage area, S~il cover with vegetation must be conducted under
this ROD. The ow~er and/or operator of Superior Block Co. must use
dust control measures such as water spray, during the operation of
mining and otheriactivities in order to reduce the release of dust
into. the air.
The city of Houghton has indicated that the city has a plan to
develop. approximately 90 acres of Isle-Royale tailings into a
residential are~. This plan includes covering tailings with 2 feet
of soils. It i~.~. expected to implement this plan within 5 years.
Since this plan is similar to the remedy under this ROD, U.S. EPA
has determined to exclude this 90 acre tract from the area to be
covered with soil and vegetation in order to allow the local
township to implement their plan. However, if this plan is not
implemented within 5 years after the date that the Remedial Design
is submitted, then the soil cover with vegetation under this ROD
must be implemented.
It is also determined that the use of tailings from the Grosse-
Point tailing pile as road-friction material over such a large
area, given the limited time period of exposure involved, would not
cause significant adverse impact to humans and/or the environment.
Tailings spread on a road during the wet conditions of winter are
unlikely to become airborne. Tailings would likely accumulate on
the sides along the roads and become mixed with existing soil. In
the Baseline Risk Assessment for OU III, the estimated cancer risks
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53
in the Isle-Royale area, like the Grosse-Point area, were
approximately 1 X 10~. This risk level is considered acceptable to
humans. At Isle-Royale, tailings are excavated, vehicular traffic
frequently resuspends the tailings, and the bare piles are subject
to wind erosion. This activity results in acceptable risk at Isle-
Royale. The mass of tailings expected to be taken from Grosse-
Point and used in road spreading activities would be many orders of
magnitude less than that from the Isle-Royale area. The risk to
the environment from the tailings spread on the road would not be
significant because the volume per area of tailings on the road
would be small, and most of the tailings would settle near the
road. Therefore, it is not expected that a large volume of
tailings on the road would travel to water bodies and subsequently
cause adverse'effects to the environment. It is estimated that an
additional 15 million dollars would be needed over the next ten
years if the Houghton County Road Commission was required to find
another source for road-friction material. Therefore, it .is
determined that the tailings in Grosse-Point can be used as road-
friction material. However, the tailings area should be covered
with enough soil to prevent the release of tailings into the air
and the lake. Once any portion of the area has been excavated to
a level seven feet above the water table (defined as the average of
seasonal highs and lows over a two year period), excavation should
cease, and that portion should either be covered with soil or
covered with soil and vegetation. After completion of excavation
of this entire area to a level seven feet above the water table,
the area should be covered with soil and vegetation pursuant to
this ROD.
The Proposed Plan excluded the slag/tailing pile located in the
Dollar Bay area (Location 8) of OU III because of the nature of
material and recent commerce activity. However, based on further
assessment, it is determined that the slag/tailing pile is located
outside of the commerce area and should be addressed under this
ROD. Several homes are located around this slag/tailing pile and
the non-cancer risk due to the ingestion of slag/tailing was
considered as unacceptable. Partial regrading of this slag/tailing
pile would be necessary to implement soil cover with vegetation.
This slag/tailing pile covers approximately 28 acres.
The North Entry (location 4), Redridge (location 11) and Freda
(location 12) tailings are excluded from the area to be covered
under this ROD. Locations 4, .11, and 12 are along the Lake
Superior shore where pounding waves and water currents will likely
. retard or destroy any remedial actions. As a result, U. S. EPA
currently believes it to be technically impracticable to implement
the chosen remedy at these locations. However, the North Entry
(location 4) and Freda (location 12) tailings, approximately 46
acres, shall be studied during Remedial Design. If U. S. EPA
determines that any portion of the two areas is sufficiently
unaffected by Lake Superior wave activity such that it can be
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54
effectively covered with soil and vegetated, then the unaffected
area or areas shall be subject to the requirements of this ROD.
Due to the these changes, the total areas in OU III to be addressed
are approximately 229 acres. However, for the purposes of
estimating the capital cost for OU III, this ROD uses 290 acres,
due to the potential inclusion of the North Entry (location 4)
tailings, and in an attempt to compensate for some uncertainty in
acreage designation. The capital cost to implement Alternative T2
for OU III is approximately $2,890,000, and annual maintenance cost
is $58,000. The present worth is approximately $2,868,000.
-------
Index of Guidelines
Torch Lake Superfund site
Operable Units I and III
Houqhton county, Michiqan
1985 Rapid Assessment of Exposure to Particulate Emissions from
Surface contamination Sites, EPA/600/8-85/002, Office of Health
and Environmental Assessment, Washinqton, D.C.
1986
Superfund Public Health Evaluation Manual, NTIS PB87-183125
9/87 Superfund Exposure Assessment Manual, OSWER Directive
#9285.5-1
1988 Guidance for Conductinq Remedial Investiqations and
Feasibility Studies Under CERCLA, Interim Final, Office of
E~erqency and Remedial Response
1/88 Preliminary Assessment Guidance, OSWER 9345 0-01
(OERR/HSCD) Final
1/83 Emerqency Response Procedures for Control of Hazardous
Substance Releases, EPA-600/D-84-023 (Rockwell International)
Final
2/88 Superfund Removal Procedures, Revision # 3 OSWER #9360.0-
038 (OSWER/OERR) Final
10/88 Guidance for Conductinq Remedial Investiqations and
Feasibility Studies Under CERCLA, OSWER #9355.3-01 (OSWER/OERR)
Final
3/87 Data Quality objectives for Remedial Response Activities:
Development Process, OSWER #9355.0-7B (CDM Federal proqrams
corp.) Final
6/84 Geophysical Techniques for Sensinq Buried Wastes and Waste
Miqration, EPA-600/7-84/064 (Technos, Inc.) Final
2/88 Laboratory Data Validation Functional Guidelines for
Evaluatinq orqanic Analyses, (Viar and Co.) Draft
9/85 Practical Guide for Ground-Water Samplinq, EPA/600/2-85/104
(Illinois st. Water survey) Final
10/85 CERCLA Compliance with Other Environmental statutes, OSWER
#9234.0-2, Final
CERCLA Compliance with Other Laws Manual, OSWER #9234.1-01
8/88
Draft
9/86 Guidelines for carcinoqen Risk Assessment Federal ~eqister,
September 24, 1986. p.JJ922 (EPA) Final
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2
9/86 Guidelines for Exposure Assessment Federal Register, .
September 24, 1986, p.34042. Final
Integrated Risk Information system (IRIS), Final
9/88
Public Health Risk Evaluation Database, Final
6/88 Community Relations in Superfund: A Handbook, OSWER
#9230.0-038, Final
11/87 Revised Procedures for Planning and Implementing Off-Site
Response Actions, OSWER # 9834.11 (OWPE), Interim Final
.12/90 Superfund Removal Procedures, Action Memorandum Guidance,
EPA/540/P-90f004
1/90 Handbook on In situ Treatment of hazardous Waste-
Contaminated Soils, EPA/540/2-90/002
12/88 Guidance on Remedial Actions for contaminated Ground Water
at Superfund Sites, EPA/540/G-88/003
12/89 Risk Assessment Guidance for superfund, Volume 1, Human
Health Evaluation Manual, Part A, Interim Final, EPA/504/1-89/002
12/86 Interim Guidance on Superfund Selection of Remedy, OSWER #
9355.0-19
4/91 Role of the Baseline Risk Assessment in Superfund Remedy
Selection Decisions, OSWER Directive 9355.0-30
References specified in Remedial Investigation Reports for
II and III, Risk Assessment Reports for OU I, II and III,
Ecological Assessment Report, and Feasibility Study Report
I/III.
OU I,
for OU
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~DMINISTRATIVE ~ECORD INDEX
TORCH LA.:E SITE. OPERABLE UNITS I AND I I I
ORIGINAL
TORCH LAKE, MICHiGAN
COC' DATE MUTHDP. ~mPIENT
---- ---- ====== :======
00/00/00
OOIOO/c.v iao!!art. Ii..
Profusor
00/0\./00 .eston USEPiI
A (.(\/00/0(;
5 . 00100/00
b 0010(\1(\0
7 00/00/00
a 00/00/00
q (\O/OO!()O USE?"
~o 00/00/00 uS iieoio!!leai Surve¥
11 00/00/00 Buruu aT IIines
12 (\(\/00/0(\
n OO/OO/OC, BlICk. J.. E.ans.
E.! !!t.Il.
14 00/00/00
15 00/00/42 QuinCY lIinin!!
COlaany
16 0(;/00/70 IIDNR
04/29/92
TITLE/DESCRIPTION
=========--=======
Calulet and Hecla lIinin!! COloany Annual
Reoorts: 1907. 1917. 1927, 1937. 1947. 1957.
1967
Exclrot frol .oot Entlt1ed: HanoDool at
IIineral uresSln~
1ncolollte ProJect Plan tor Characterlzatl0n
at 8ani Mnolailes Ino cover pa!!e,
"ao ot Lall Suplrl0r uistrlct
IIaolLaurlUi yuadranl!le
!lall--Rolds. letllnds. Soil
!lODd,'s Industrial IIanual Fal!,s.on Univ,rsal
Oil ~roduct5 tor Years 1969, 1984
NPL Candidate: Narrative SUllary
National PriorIties LIst Site: Taren Lat,
Fa!!IS Fro. IIlneral Resources at the unIted
Statls tar 'ears 1910, 1920. 193v! 1940
Fa!!IS Fro. Vol. 3 at lIinera15 YearDooi tor
'earl 1955. 1960. 1960, 1975
Population ot Placls--ftichi!!an
Revised lIanulcript: EpizDPtic MeDDlis,S In
Fish Fro. a Lail Pollutld by COODy lIinin!!
laltll .
Various H~spaper Articles trol 1963-64
"ssav of laste Sinds
6rouno later. 6eolo!!y of Ke...na. Peninsuia.
'Iiehl!!an
N'
~. .
FASES
==--
146
12
14
5
34
21
:8
16
44
4i
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