[Federal Register Volume 75, Number 174 (Thursday, September 9, 2010)]
[Rules and Regulations]
[Pages 54779-54789]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 2010-22489]
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ENVIRONMENTAL PROTECTION AGENCY
40 CFR Part 300
[EPA-HQ-SFUND-1983-0002; FRL-9198-6]
National Oil and Hazardous Substance Pollution Contingency Plan;
National Priorities List; Partial Deletion of the Denver Radium
Superfund Site
AGENCY: Environmental Protection Agency.
ACTION: Direct final rule.
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SUMMARY: The Environmental Protection Agency (EPA) Region 8 is
publishing a direct final Notice of Partial Deletion of
[[Page 54780]]
the Denver Radium Superfund Site (Site). Specifically, EPA intends to
delete from the National Priorities List (NPL) each of the 11 operable
units at the Denver Radium Site, located in the City and County of
Denver, Colorado. Groundwater contamination associated with Operable
Unit 8 will remain on the NPL. The NPL, promulgated pursuant to section
105 of the Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA) of 1980, as amended, is an appendix of the
National Oil and Hazardous Substances Pollution Contingency Plan (NCP).
This direct final partial deletion is being published by EPA with the
concurrence of the State of Colorado, through the Colorado Department
of Public Health and Environment, because EPA has determined that all
appropriate response actions at these identified parcels under CERCLA,
other than operation, maintenance, and five-year reviews, have been
completed. However, this partial deletion does not preclude future
actions under Superfund.
This partial deletion pertains to each of the 11 operable units of
the Denver Radium Superfund Site. Groundwater contamination associated
with Operable Unit 8 will remain on the NPL and is not being considered
for deletion as part of this action.
DATES: This direct final rule is effective November 8, 2010 unless EPA
receives adverse comments by October 12, 2010. If adverse comments are
received, EPA will publish a timely withdrawal of the direct final
partial deletion in the Federal Register informing the public that the
partial deletion will not take effect.
ADDRESSES: Submit your comments, identified by Docket ID no. EPA-HQ-
SFUND-1983-0002, by one of the following methods:
http://www.regulations.gov. Follow on-line instructions
for submitting comments.
E-mail: [email protected].
Fax: (303) 312-7110 (Attention: John Dalton, Public
Affairs and Involvement)
Mail: John Dalton, Public Affairs and Involvement (8OCPI),
U.S. EPA Region 8, 1595 Wynkoop Street, Denver, CO 80202-1129, (303)
312-6633.
Hand Delivery: U.S. EPA Region 8, 1595 Wynkoop Street,
Denver, CO. Such deliveries are only accepted during the Docket's
normal hours of operation, and special arrangements should be made for
deliveries of boxed information.
Instructions: Direct your comments to Docket ID no. EPA-HQ-SFUND-
1983-0002. EPA's policy is that all comments received will be included
in the public docket without change and may be made available online at
http://www.regulations.gov, including any personal information
provided, unless the comment includes information claimed to be
Confidential Business Information (CBI) or other information whose
disclosure is restricted by statute. Do not submit information that you
consider to be CBI or otherwise protected through http://www.regulations.gov or e-mail. The http://www.regulations.gov Web site
is an ``anonymous access'' system, which means EPA will not know your
identity or contact information unless you provide it in the body of
your comment. If you send an e-mail comment directly to EPA without
going through http://www.regulations.gov, your e-mail address will be
automatically captured and included as part of the comment that is
placed in the public docket and made available on the Internet. If you
submit an electronic comment, EPA recommends that you include your name
and other contact information in the body of your comment and with any
disk or CD-ROM you submit. If EPA cannot read your comment due to
technical difficulties and cannot contact you for clarification, EPA
may not be able to consider your comment. Electronic files should avoid
the use of special characters, any form of encryption, and be free of
any defects or viruses.
Docket
All documents in the docket are listed in the http://www.regulations.gov index. Although listed in the index, some
information is not publicly available, e.g., CBI or other information
whose disclosure is restricted by statute. Certain other material, such
as copyrighted material, will be publicly available only in the hard
copy. Publicly available docket materials are available either
electronically in http://www.regulations.gov or in hard copy at:
U.S. Environmental Protection Agency Region 8 Records Center, 1595
Wynkoop Street, Denver, CO 80202, Hours: M-F, 8 a.m. to 4 p.m.
Colorado Department of Public Health and Environment, 4300 Cherry Creek
Drive South, Denver, CO 80246, Hours: M-F, 8 a.m. to 5 p.m.
FOR FURTHER INFORMATION CONTACT: Rebecca Thomas, Project Manager (8EPR-
SR), U.S. Environmental Protection Agency Region 8, EPR-SR, 1595
Wynkoop Street, Denver, CO 80202-1129, (303) 312-6552,
[email protected].
SUPPLEMENTARY INFORMATION:
Table of Contents
I. Introduction
II. NPL Deletion Criteria
III. Partial Deletion Procedures
IV. Basis for Site Partial Deletion
V. Partial Deletion Action
I. Introduction
EPA Region 8 is publishing this direct final Notice of Partial
Deletion for the Denver Radium Superfund Site (Site) from the National
Priorities List (NPL). This partial deletion pertains to each of the 11
operable units of the Denver Radium Superfund Site, with the exception
of groundwater contamination associated with Operable Unit 8. The NPL
constitutes Appendix B of 40 CFR part 300, which is the Oil and
Hazardous Substances Pollution Contingency Plan (NCP), which EPA
promulgated pursuant to Section 105 of the Comprehensive Environmental
Response, Compensation and Liability Act (CERCLA) of 1980, as amended.
EPA maintains the NPL as the list of sites that appear to present a
significant risk to public health, welfare, or the environment. Sites
on the NPL may be the subject of remedial actions financed by the
Hazardous Substance Superfund (Fund). This partial deletion of the
Denver Radium Superfund Site is proposed in accordance with 40 CFR
300.425(e) and is consistent with the Notice of Policy Change: Partial
Deletion of Sites Listed on the National Priorities List, 60 FR 55466
(Nov. 1, 1995). As described in Section 300.425 (e)(3) of the NCP, a
portion of a site deleted from the NPL remains eligible for Fund-
financed remedial action if future conditions warrant such actions.
Because EPA considers this action to be non-controversial and
routine, this action will be effective November 8, 2010 unless EPA
receives adverse comments by October 12, 2010. Along with this direct
final Notice of Partial Deletion, EPA is co-publishing a Notice of
Intent for Partial Deletion in the ``Proposed Rules'' section of the
Federal Register. If adverse comments are received within the 30-day
public comment period on this partial deletion action, EPA will publish
a timely withdrawal of this direct final Notice of Partial Deletion
before the effective date of the partial deletion, and the partial
deletion will not take effect. EPA will, as appropriate, prepare a
response to comments and continue with the deletion process on the
basis of the Notice of Intent for Partial Deletion and the comments
already received. There will be no additional opportunity to comment.
[[Page 54781]]
Section II of this document explains the criteria for deleting
sites from the NPL. Section III discusses procedures that EPA is using
for this action. Section IV discusses the Denver Radium Superfund Site
and demonstrates how portions of the Site proposed for deletion meet
the deletion criteria. Section V discusses EPA's action to partially
delete the Site from the NPL unless adverse comments are received
during the public comment period.
II. NPL Deletion Criteria
The NCP establishes the criteria that EPA uses to delete sites from
the NPL. In accordance with 40 CFR 300.425(e), sites may be deleted
from the NPL where no further response is appropriate. In making such a
determination pursuant to 40 CFR 300.425(e), EPA will consider, in
consultation with the state, whether any of the following criteria have
been met:
i. Responsible parties or other persons have implemented all
appropriate response actions required;
ii. All appropriate Fund-financed response under CERCLA has been
implemented, and no further response action by responsible parties is
appropriate; or
iii. The remedial investigation has shown that the release poses no
significant threat to public health or the environment and, therefore,
the taking of remedial measures is not appropriate.
Pursuant to CERCLA section 121(c) and the NCP, EPA conducts five-
year reviews to ensure the continued protectiveness of remedial actions
where hazardous substances, pollutants, or contaminants remain at a
site above levels that allow for unlimited use and unrestricted
exposure. EPA conducts such five-year reviews even if a site is deleted
from the NPL. EPA may initiate further action to ensure continued
protectiveness at a deleted site if new information becomes available
that indicates it is appropriate. Whenever there is a significant
release from a site deleted from the NPL, the deleted site may be
restored to the NPL without application of the hazard ranking system.
III. Partial Deletion Procedures
The following procedures apply to partial deletion of the 11
operable units of the Site:
(1) EPA consulted with the State of Colorado prior to developing
this direct final Notice of Partial Deletion and the Notice of Intent
for Partial Deletion co-published in the ``Proposed Rules'' section of
the Federal Register.
(2) EPA has provided the State 30 working days for review of this
notice and the parallel Notice of Intent for Partial Deletion prior to
their publication today, and the State, through the Colorado Department
of Public Health and Environment, has concurred on the partial deletion
of the Site from the NPL.
(3) Concurrently with the publication of this direct final Notice
of Partial Deletion, a notice of the availability of the parallel
Notice of Intent for Partial Delete is being published in a major local
newspaper, The Denver Post. The newspaper notice announces the 30-day
public comment period concerning the Notice of Intent for Partial
Deletion of the Site from the NPL.
(4) The EPA placed copies of documents supporting the partial
deletion in the deletion docket and made these items available for
public inspection and copying at the Site information repositories
identified above.
(5) If adverse comments are received within the 30-day public
comment period on this partial deletion action, EPA will publish a
timely notice of withdrawal of this direct final Notice of Partial
Deletion before its effective date and will prepare a response to
comments and continue with the deletion process on the basis of the
Notice of Intent for Partial Deletion and the comments already
received.
Deletion of a portion of a site from the NPL does not itself
create, alter, or revoke any individual's rights or obligations.
Deletion of a portion of a site from the NPL does not in any way alter
EPA's right to take enforcement actions, as appropriate. The NPL is
designed primarily for informational purposes and to assist EPA
management. Section 300.425(e)(3) of the NCP states that the deletion
of a site from the NPL does not preclude eligibility for future
response actions, should future conditions warrant such actions.
IV. Basis for Partial Site Deletion
The following information provides EPA's rationale for deleting
from the NPL each of the 11 operable units of the Denver Radium Site,
with the exception of groundwater contamination associated with
Operable Unit 8:
Site Location
The Denver Radium Superfund Site (EPA ID: COD980716955), located in
Denver, Colorado, consists of more than 40 contaminated properties.
These properties have been grouped into 11 operable units which, except
for groundwater contamination associated with OU 8, are proposed for
deletion from the NPL. At certain locations, marked with an asterisk,
waste has been left in place. These locations will require continued
operation and maintenance to inspect the integrity of the cap and
ensure institutional controls (ICs) are functioning properly. The Site
was added to the Superfund NPL in 1983 (48 FR 40658, September 8,
1983).
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OU Property name Address
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OU1.................... B & C Metals (now 1623-1625 West 12th
Martin Shea Millworks). Ave.
OU1.................... Erickson Monuments..... 1241-1245 Quivas St.
OU1.................... Materials Handling, Inc 1740 West 13th Ave.
OU1.................... Rudd................... 1223-1229 Quivas St.
OU1.................... City/County of Denver East of B & C Metals,
Alley/Driveway. between 12th Ave. and
Erickson Monuments.
OU2*................... DuWald Steel (now Atlas 1100 Umatilla Street.
Metals & Iron).
OU2.................... Rocky Mountain Research 1020-1030 Yuma Street.
Corporation (now A1
Transmission and
Nationwide Courier).
OU2.................... G&K Services........... 999 Vallejo Street.
OU2.................... Jenkins Property....... 2191 West 10th Street.
OU2.................... Staab Property......... 2121 West 10th Street.
OU2.................... Air Conditioning, Inc.. 1001 South Tejon
Street.
OU2*................... Burlington Northern Between 10th & 11th
Railroad. Avenues.
OU2.................... Colorado DOT--Jerome 2300 West 11th Avenue.
Maintenance Yard.
OU2.................... Flame Spray, Inc....... 1900 West 12th Avenue.
OU2.................... Alpha Omega Electronics 1010 Yuma Street.
OU2.................... Capital Management 1050 Yuma Street.
Realty (now Royal
Textile).
OU2.................... Denver Water Board..... 1600 West 12th Avenue.
[[Page 54782]]
OU3.................... Creative Illumination, 1298 South Kalamath
Inc. Street.
OU3*................... Packaging Corporation 1377 South Jason
of America (PCA) (now Street.
Caraustar Custom
Packaging).
OU3.................... GT Car Shop/Aspen 1235 South Jason
Design and Street.
Manufacturing.
OU3*................... Denver right-of-way.... 1377 S. Jason Street.
OU3.................... Kwan Sang Noodle 1140 West Louisiana.
Company, formerly
Titan Labels.
OU3.................... Various tenants........ 1300 South Jason
Street.
OU3*................... Central & Sierra Between W. Louisiana &
Railroad. W. Florida Streets.
OU4*................... Robinson Brick and Tile 500 South Santa Fe
Company (ROBCO) (now Drive.
Home Depot).
OU5.................... Denver and Rio Grande Immediately East of
Western Railroad ROW. OU4.
OU6.................... Alley in City and Between Mariposa and
County of Denver right- Lipan Streets and
of-way. between 5th and 6th
Avenues.
OU6.................... Allied (General 1271 West Bayaud
Chemical). Avenue.
OU6.................... Brannan Sand and Gravel 61st Ave. and Clear
Creek.
OU6.................... Central and Sierra 2301 15th Street.
Railroad right-of-way/
Centennial Tire.
OU6.................... Denver Water Department 1190 Yuma Street.
OU6.................... Public Service Company. South Pecos St. & West
Arizona Ave.
OU6.................... Ruby Hill Park......... Jewell St. and S.
Platte River Drive.
OU6.................... Environmental Metals, 1155 West 5th Avenue.
Inc. (bldg has been
razed).
OU7.................... 9th Ave.: Ogden St. to N/A.
Cheesman Pk.
OU7.................... 11th Ave.: Josephine N/A.
St. to Cheesman Pk.
OU7.................... 23rd St.: California N/A.
St. to Lawrence St.
OU7.................... Corona: 7th Ave. to N/A.
10th Ave.
OU7.................... Downing St .: 7th Ave. N/A.
to 10th Ave.
OU7.................... Humboldt St.: 7th Ave. N/A.
to 9th Ave.
OU7.................... Lafayette St.: 1st Ave. N/A.
to 10th Ave.
OU7.................... Marion St.: 6th Ave. to N/A.
10th Ave.
OU7.................... York St.: 6th Ave. to N/A.
13th Ave.
OU8.................... S.W. Shattuck Chemical 1805 South Bannock
Company (soil). Street.
OU8*................... S.W. Shattuck Chemical 1805 South Bannock
Company (groundwater). Street.
OU9A................... International House of 2001, 2015, and 2017
Pancakes and Larry's East Colfax Avenue.
Trading Post (now
Mama's Caf[eacute],
Herbs and Art, and
Purple Haze).
OU9B*.................. Robinson Brick and Tile 500 South Santa Fe
Company (ROBCO) Metals Drive.
(now Home Depot).
OU10................... Card Corp.............. 1314 West Evans
Avenue.
OU11................... Commercial Investors 1285-1295 South Santa
Realty (formerly owned Fe Drive.
by Thomas Real Estate
Corp.) (now Murphy
Beds and a Starbucks).
------------------------------------------------------------------------
Site History
OU1
Contamination at OU1 resulted from a radium, vanadium, and uranium
processing facility at 1201 Quivas Street owned by the Pittsburgh
Radium Company (PRC) from 1925 until 1926. The Radium Ores Company,
which was associated with PRC, operated the facility until
approximately 1927. Approximately 120 tons of carnotite and 500 tons of
vanadium were processed monthly.
OU2
The contamination at Operable Unit 2 is believed to be from
activities of the Schlesinger Radium Company which began operations in
1914 where Atlas Metals & Iron (formerly DuWald Steel Corporation)
currently is located (1100 Umatilla Street). In 1917, Schlesinger
Radium Company became Radium Company of Colorado. Radium Company of
Colorado ceased operations at OU2 in 1924. Complex Ore Recovery Company
occupied the 1100 Umatilla property until 1928. It is not known whether
that company also processed radium ore.
Since 1914, at least 38 companies have operated within the operable
unit. OU2, as originally designated, included only the 1100 Umatilla
and 1020 and 1030 Yuma Street properties. The other properties were
included as subsequent investigations revealed additional
contamination.
OU3
It is believed that the vacant lot, located at 1000 South Louisiana
and owned by Packaging Corporation of America, may have been the site
of a smelter that operated in the late 19th century. This smelter may
have been turned into a radium-processing facility in the early 20th
century. The Chemical Products Company, which occupied portions of OU3
between 1918 and 1921, separated radium and vanadium from uranium ores
for the National Radium Institute. Most of the buildings associated
with radium processing were demolished prior to 1970. The exception was
a brick building located at 1298 South Kalamath Street, which was
purchased by Creative Illumination, Inc. and used for light-fixture
fabrication. The Creative Illumination, Inc. building was demolished
during remediation activities.
OU4/5
OU4 (ROBCO) was the site of a radium processing facility
established by the National Radium Institute (NRI) in 1913. The NRI
facility was created for the purpose of developing and demonstrating
the commercial feasibility of radium extraction techniques. This
facility operated on the site for approximately four years and then
closed after producing 7.5 grams of radium and successfully
demonstrating commercially feasible extraction processes. ROBCO
acquired the property in the 1940s and used it as a brick and tile-
manufacturing site until the 1980s. The radium-contaminated area of OU5
(D&RGW right-of-way) covers 1.6 acres. This property is crossed by
several rail lines and contains a network of electronic controls to
operate railway lights and switches. OU5 has been in use as a railroad
right-of-way throughout the
[[Page 54783]]
industrial and commercial use of the adjacent ROBCO property.
OU6, OU9A, OU11
Much of the radiological contamination present at OU6, OU9A and
OU11 is believed to be either the direct result of radium and uranium
processing on the property or the result of deposition of residual
wastes from other processing sites.
OU7
These properties comprise a number of city streets which were
underlain by radium-contaminated soil. Radium production from about
1914 to the mid-1920s generated large quantities of radioactive
residues in the Denver area. Radium-contaminated tailing and other
wastes were discarded or left on site when the facilities were closed.
Due to changes in ownership and use of the properties, the residues
were used as cover, fill, foundation material, and as aggregate in
concrete and asphalt mixtures.
OU8
The Shattuck property has been the location of several mineral-
processing operations since the early 1900s. The operations included
the extraction of molybdenum and vanadium from ores, processing of
``radium slimes'' for the production of radium salts and uranium
compounds, recovery of rhenium as a by-product of molybdenum
production, and for a short period of time processing of depleted
uranium. The primary site contaminants were radium, thorium, uranium,
molybdenum, arsenic, selenium, and several volatile and semi-volatile
organics. Shattuck's operations ceased in 1984.
OU9B
OU 9B-ROBCO Metals was designated to distinguish response actions
addressing metals contamination from response actions addressing the
OUs 4/5 radium contamination. In May 1988, excavation of the
radiologically contaminated soil began at OUs 4/5. In September 1988,
during the course of the radium cleanup, metals contamination was
discovered on the ROBCO property. Contaminants of concern included
arsenic, lead, and zinc. An investigation to characterize the nature
and extent of metals contamination was conducted in 1989 and 1990. This
metal contamination is believed to be from the operation of the Tabor
Smelter on this property in the 1880s and 1890s.
OU10
Contamination at OU10 was from PRC processing of vanadium between
1920 and 1924. During 1924, PRC is believed to have processed as much
as 10 tons of vanadium daily. OU1-OU11, with the exception of OU8
groundwater, are proposed for partial deletion.
Characterization of Risk
Radium and its associated decay products were the primary
contaminants of concern at the Denver Radium Site. Other contaminants
at the site were thorium, uranium, arsenic, zinc, and lead.
The elevated concentration of radium and the uncontrolled state of
contaminants at the Denver Radium Site posed a health hazard due to
three potential exposure pathways: Inhalation of radon gas and its
decay products, direct gamma radiation exposure from the decay of
radium and ingestion or inhalation of radium-contaminated materials.
Ingestion or contact with contaminated groundwater is not a principal
exposure pathway. There is no surface water on site.
Inhalation of radon decay products presents the greatest health
risk from long-term exposure. Prolonged inhalation of air with a high
concentration of radon decay products has been conclusively shown to
increase the risk of lung cancer. Dispersion quickly dilutes radon
emanating from radium-contaminated ground. The greatest risk from radon
is when it builds up in well-sealed buildings. Radon decay product
contamination in buildings (where applicable) was as much as 0.30
working levels (WL) above the EPA standard of 0.02.
Remedial Investigation and Feasibility Study
The Remedial Investigation (RI) report for the Denver Radium
Superfund Site was issued in April 1986. The Feasibility Study (FS) was
issued in September 1987. The site-wide RI focused on radium and
uranium processing residues discarded in the early 1900s. These
residues contain uranium, radium, and thorium.
A number of Remedial Action alternatives were evaluated in the
site-wide FS including: No Action; On-Site Processing with Permanent
Disposal; In-Situ Vitrification; On-Site Permanent Disposal; Off-Site
Permanent Disposal, and On-Site Temporary Containment with Off-Site
Permanent Disposal. These site-wide RI and FS reports provided the
basis for selecting remedies in most of the Records of Decision.
Separate RI/FS reports were generated for the metals contamination at
OU4 (ROBCO) and the contamination at OU8 (Shattuck).
Remedial Action Objectives
The following objectives were identified for soil across the site:
Remedial actions shall be conducted so as to provide reasonable
assurance that, as a result of residual radioactive materials from any
designated processing site:
(a) The concentration of radium-226 in land averaged over any area
of 100 square meters shall not exceed the background level by more
than--
(1) 5 pCi/g, averaged over the first 15 centimeters of soil below
the surface, and
(2) 15 pCi/g, averaged over 15-centimeter thick layers of soil more
than 15 centimeters below the surface.
Supplemental Standards: (OUs 2, 3, 4, 9B)
40 CFR Part 192 provides that under certain circumstances the
agency performing the cleanup may choose a remedial action that does
not achieve complete removal of radium contamination to the levels
described in 40 CFR Section 192.12(a). Under 40 CFR Section 192.21(c),
``supplemental standards'' can be applied when:
``The estimated cost of remedial action to satisfy 40 CFR
Section 192.12(a) at a * * * site * * * is unreasonably high
relative to the long-term benefits, and the residual radioactive
materials do not pose a clear present or future hazard. The
likelihood that buildings will be erected or that people will spend
long periods of time at such a vicinity site should be considered in
evaluating this hazard. Remedial action will generally not be
necessary where residual radioactive materials have been placed
semi-permanently in a location where site-specific factors limit
their hazard and from which they are costly or difficult to remove,
or where only minor quantities of residual radioactive materials are
involved. Examples are residual radioactive materials under hard
surface public roads and sidewalks, around public sewer lines, or in
fence post foundations.''
The following objectives were identified for buildings across the
site:
(b) In any occupied or habitable building--
(1) The objective of remedial action shall be, and reasonable
effort shall be made to achieve, an annual average (or equivalent)
radon decay product concentration (including background) not to exceed
0.02 WL. In any case, the radon decay product concentration (including
background) shall not exceed 0.03 WL, and
(2) The level of gamma radiation shall not exceed the background
level by more than 20 microroentgens per hour.
[[Page 54784]]
The following objectives were identified for groundwater:
OU8--Restoration of groundwater quality to Safe Drinking Water Act
maximum contaminant levels through monitored natural attenuation.
OU9B--No remedial action objectives were identified for groundwater
because the alluvial aquifer is not presently used as a drinking water
source and is unlikely to be used as a drinking water source due to
poor natural quality (i.e., high total dissolved solids), low yield,
and its location (i.e., in an industrial area between a major rail
corridor and an interstate highway). Groundwater protection is achieved
by controlling the source of contamination and periodic monitoring to
verify that contamination does not reach the South Platte River in
detrimental concentrations. Deed restrictions include a prohibition on
placement of any wells on the Site for the purpose of supplying
drinking water.
Selected Remedies
The RODs for OUs 1, 2, 3, 4/5, 6/9/11, and 10 each selected
excavation and off-site permanent disposal as the remedy. At the time
the RODs were signed, there were no disposal facilities in the nation
that accepted radioactive waste. For this reason, the RODs included
temporary on-site land storage of the contaminated materials with
subsequent off-site permanent disposal. Plans for on-site temporary
land storage were abandoned for all operable units, with the exception
of OU 4/5, when a permanent disposal facility opened before excavation
began. Excavated material was shipped by rail to Envirocare of Utah,
Inc., a disposal facility in Tooele County, Utah. For OU 4/5,
contaminated soil was stockpiled on the ROBCO property until the
permanent disposal facility became available and a transportation
contract was negotiated.
OU1
In the Record of Decision (ROD), dated September 1987, EPA selected
excavation and off-site disposal as the remedy for OU1. The objectives
of this remedy were to prevent: Radiation exposure due to inhalation of
radon gas and its daughter products; radiation exposure due to
inhalation and ingestion of long-lived radionuclides; and direct
exposure to gamma radiation.
OU2
In the ROD, dated September 1987, EPA selected excavation and off-
site permanent disposal as the remedy for OU2. The objectives of this
remedy were to prevent: Radiation exposure due to inhalation of radon
gas and its daughter products; radiation exposure due to inhalation and
ingestion of long-lived radionuclides; and direct exposure to gamma
radiation.
The scope of Remedial Action detailed in the ROD included:
Decontaminating the roof of the Rocky Mountain Research
Corporation building and excavating the majority of the approximately
15,400 cubic yards of contaminated material located under buildings and
in open areas on the properties, and placing the material in a
temporary on-site land storage facility,
Maintaining the 6-inch-thick concrete pad, covering
contaminated soil on the northeast part of the Atlas Metals & Iron
(formerly DuWald Steel Corporation) property,
Removing the contaminated material from the temporary
storage and containment locations to the permanent disposal facility
when such a facility became available.
In September 1993, EPA issued an Explanation of Significant
Differences (ESD) to address on-site conditions that became apparent
after the ROD was signed. The changes made to the remedy selected for
OU2 in the ROD were:
A greater volume of radium-contaminated soil was excavated
and removed.
Relatively small amounts of radium contamination were left
on the 1100 Umatilla Street property. Radium contaminated soil was left
in place in the following locations: (a) Under structures on the Du-
Wald property, (b) near the underground power line, (c) within a four
foot buffer zone around water and sewer lines, (d) below the ground
water level, and (e) on the Burlington Northern Railroad (BNRR) right-
of-way.
Institutional controls (ICs) were required where waste was
left in place.
There was no temporary on-site storage.
Soil containing commingled radium and lead was solidified
in a cement matrix prior to shipment to a permanent, off-site disposal
facility.
OU3
In the ROD, dated September 1987, EPA selected excavation and off-
site disposal as the remedy for OU3. The objectives of this remedy were
to prevent: Radiation exposure due to inhalation of radon gas and its
daughter products; radiation exposure due to inhalation and ingestion
of long-lived radionuclides; and direct exposure to gamma radiation.
In December 1993, EPA issued an ESD to address on-site conditions
that became apparent after the ROD was signed. The ESD presents the
changes that were made to the remedy selected for OU3; briefly, the
differences were:
No temporary storage prior to removal and shipment of
contaminated material to the permanent off-site disposal facility.
Over 52,000 cubic yards of contaminated soil were
excavated and the area of contamination was extended east of South
Jason Street.
As part of the remediation, the Creative Illumination
building was demolished, contaminated material was removed, and the
contaminated materials were shipped to the off-site repository.
There was no excavation of contaminated soil below
groundwater, near water lines, or under South Jason Street, Platte
River Drive and the Packaging Corporation of America building.
ICs were required where waste was left in place.
OU4/5
EPA selected excavation and off-site disposal as the remedy for
this OU in a ROD dated September 30, 1986. The objectives of this
remedy were to prevent: Radiation exposure due to inhalation of radon
gas and its daughter products; radiation exposure due to inhalation and
ingestion of long-lived radionuclides; and direct exposure to gamma
radiation. The ROD determined that the shallow alluvial aquifer is not
a drinking water source.
In December 1994, EPA issued an ESD to address on-site conditions
that became apparent after the ROD was signed. The ESD describes in
more detail the changes that were made to the remedy selected for OU4
and OU5. The remedy, as implemented, differed in two respects from the
remedy chosen in the 1986 ROD. Those differences were:
The volume of contaminated soil increased; and
Relatively small volumes of contaminated soil were left in
place below the groundwater level.
ICs were required on the OU4 property where wastes were
left in place.
OU6, OU9A, OU11
EPA selected excavation and off-site disposal as the remedy for
OU6, OU9A, and OU11 in a ROD dated September 29, 1987. The objectives
of this remedy were to prevent: Radiation exposure due to inhalation of
radon gas and its daughter products; radiation exposure due to
inhalation and ingestion of long-lived radionuclides; and direct
exposure to gamma radiation.
[[Page 54785]]
Remedial design at these operable units focused on excavation and
direct off-site disposal of radiologic waste materials.
In January 1995, EPA issued an ESD to address on-site conditions
that became apparent after the ROD was signed. The ESD describes the
changes that were made to the remedy selected for OU6, OU9A, and OU11.
Briefly, these differences include:
A relatively small volume of radium-contaminated soil was
left in place at the following locations in OU6: a) near a concrete box
culvert on the Confluence Park property; and b) under the Environmental
Materials (EMI) Building.
ICs were required on the OU6 property where wastes were
left in place. Note: Even though the 1995 ESD describes waste left in
place, all contamination was subsequently removed. ICs are not
required.
Additional properties were found to be contaminated and a
greater volume of radium-contaminated soil was excavated and placed in
a permanent off-site repository.
Soil commingled with metals contamination was shipped to
the permanent off-site disposal facility.
OU7
EPA issued a ROD for OU7 on March 24, 1986 that combined features
of the Excavation and Off-site Disposal alternative with a no action
alternative. The ROD called for leaving the contaminated material in-
place and required ICs to monitor all maintenance, repair, or
construction activities in the affected streets. Any contaminated
material excavated during these activities would be shipped off site
for disposal.
The objectives of this remedy were to prevent: Radiation exposure
due to inhalation of radon gas and its daughter products; radiation
exposure due to inhalation and ingestion of long-lived radionuclides;
and direct exposure to gamma radiation.
In September 1992, EPA issued an ESD to address on-site conditions
that became apparent after the ROD was signed. This ESD amended the
existing ROD to allow for reburial of excavated materials. The
significant difference from the original remedy allows on-site
retention and reburial of radium-contaminated material excavated during
all maintenance, repair or other construction activities. Should
maintenance, repair or other construction activities be required,
excavated radium-contaminated materials will be retained and reburied
on site if feasible, provided that the area to be excavated is not
greater than 20% of the total area of the roadway in one city block.
Special variance to the 20% limit may be granted by the CDPHE should an
unusual circumstance require such a variance. Reburied materials will
be covered with a new, hard surface, such as asphalt or concrete having
a minimum depth of 6 inches to ensure no direct exposure. If retention
and reburial are not feasible, the materials will be disposed at a
licensed, off-site disposal facility, consistent with the ROD.
OU8
The original ROD for Shattuck was signed on January 28, 1992. EPA
selected on-site soil stabilization and solidification to prevent
further degradation of groundwater and allow for natural attenuation
with monitoring for groundwater. Groundwater monitoring will be
performed to (1) monitor the effectiveness of source control measures,
and (2) monitor attenuation of the plume until it meets maximum
contaminant levels for contaminants of concern. An IC program was an
integral part of the remedy and required restrictions against
excavating into the cover and stabilized materials, prohibition of the
construction of enclosed structures on the disposal site, restrictions
against the use of groundwater, and restrictions to prevent
agricultural use of the site. In 1999, EPA conducted a discretionary
five-year-review of the Shattuck OU and found deficiencies in aspects
of the design and integrity of the on-site disposal cell. Based on
these findings, EPA could not be assured of the long-term protection of
the original remedy. In addition to the technical concerns raised by
the 1999 five-year review, the State, Denver, elected officials, and
the local community requested that EPA consider other alternatives to
the on-site remedy to allow for unrestricted use of the site.
In June 2000, after developing a proposed plan and receiving public
input, EPA selected off-site removal in a ROD Amendment. Off-site
disposal benefits included the following:
Long-term protection of human health and the environment;
Removal of potential source material for future
groundwater contamination;
Disposal of material in a permitted facility;
Unrestricted future land use; and
Monitored attenuation of the plume until it meets maximum
contaminant levels for contaminants of concern for groundwater use
remain as required in the 1992 Record of Decision.
An ESD was issued for the Shattuck Site in February 2007. The ESD was
required due to the elevated costs from the original estimate based on
the 2000 ROD. The 2000 estimate cost for the off-site removal was $29
million with a final cost of $57 million. Reasons for the increased
costs are described in the ESD.
OU9B
As discussed above, OU9B was designated when substantial metals-
contaminated soil, not commingled with radium wastes, was discovered
during implementation of the OU 4/5 remedy. At this OU, EPA selected a
remedy leaving the metals-contaminated soil on site under a protective
soil cover and implemented ICs. The objectives of the remedy were to:
Prevent direct contact with or ingestion of metals-
contaminated soil that exceeds the health-based action levels and
monitor migration of the contaminants of concern in groundwater that
could result in degradation of water quality in the South Platte River.
Cap the metals-contaminated soil, conduct environmental
monitoring to ensure the effectiveness of the Remedial Action, and
implement ICs to limit use of groundwater at the site and maintain the
integrity of the cap.
OU10
In the ROD, dated June 30, 1987, EPA selected excavation and off-
site disposal as the remedy for OU10. The objectives of this remedy
were to prevent: Radiation exposure due to inhalation of radon gas and
its daughter products; radiation exposure due to inhalation and
ingestion of long-lived radionuclides; and direct exposure to gamma
radiation.
Response Actions
OU1
Remediation activities at OU1 were conducted in three phases to
facilitate construction and to accommodate the various business
activities in the unit. Construction began on October 2, 1989 and
concluded on July 18, 1991. The quantity of material removed during
remediation was 32,665 tons.
OU2
Remedial Actions at OU2 began in August 1990 and, except for ICs,
were completed in August 1993. Activities included:
Excavation of radium-contaminated soil in open areas.
Analysis of the contaminated materials for disposal to
ensure compliance with transportation and disposal regulations.
[[Page 54786]]
Shipment of contaminated materials to the permanent off-
site disposal facility.
Confirmation sampling of excavated area.
A total of 14,211 tons of radiologic and commingled material was
excavated and shipped off site. The commingled material was stabilized
by solidification prior to off-site disposal. A Supplemental Standards
Report was prepared in May 1994 to document that 11,060 cubic yards of
radiological contaminated soil were left in place on the Burlington
Northern Railroad property and the 1100 Umatilla Street property (Atlas
Metals and Iron) at OU2.
Pursuant to the terms of an administrative settlement agreement
(November 22, 2005), the current owner of the former DuWald property,
Atlas Umatilla, LLC, has prepared and is implementing an O&M Plan and
signed and executed an environmental covenant on June 25, 2006. The
environmental covenant restricts disturbance of the concrete cap and
subsurface soil. In addition, Denver's zoning ordinance and its radium
fee ordinance provide ICs generally at properties in OU2 where radium-
contaminated soil remains in place under supplemental standards.
OU3
Remedial Actions at OU3 began in August 1989 and were completed in
September 1991. A phased approach to the cleanup allowed on-site
businesses to maintain operations throughout the excavation and
shipment of 63,672 tons of contaminated material from OU3. Activities
included:
Excavation of radium-contaminated soil in open areas;
Demolition of certain radium-contaminated buildings;
Analysis of the contaminated materials to be disposed to
ensure compliance with transportation and disposal regulations;
Shipment of contaminated materials to the permanent off-
site disposal facility; and
Confirmation sampling of excavated area.
The Creative Illumination building was demolished and 3,657 tons of
radium-contaminated materials were excavated and removed from this
location. A total of 32,389 tons of radium-contaminated soil was
excavated and removed from the Packaging Corporation of America (PCA)
property and a vacant lot owned by PCA located at 1000 West Louisiana.
Other activities included the excavation and off-site disposal of
27,626 tons of radiologically contaminated soil. Remediation of OU3 was
completed when 50 tons of radiologically contaminated soil were
excavated from the GT Car Shop and Aspen Design and Manufacturing
properties for off-site disposal.
OU4/5
Remedial Action at OU4 and OU5 included the following:
Excavation of radium-contaminated soil;
Demolition of certain radium-contaminated buildings;
Analysis of the contaminated materials to ensure
compliance with transportation and disposal regulations;
Shipment of contaminated materials to the permanent off-
site facility; and
Confirmation sampling of excavated area.
Remedial Action at OU4/5 was conducted in phases, beginning in
April 1988 and, except for ICs, completed in March 1991. A total of
57,586 tons of radiologically contaminated material was excavated
during the initial phase of the cleanup. This material was stockpiled
on site temporarily until it could be transported to the off-site
disposal facility. Approximately 1,290 tons of soil, contaminated with
elevated levels of Thorium-230, were removed during a later phase of
the project. The stockpiled material, as well as an additional 9,677
tons of contaminated material situated immediately below the stockpile,
were shipped during a later phase of the cleanup. Finally, 29,721 tons
of radiologically contaminated soil were excavated and transported by
rail in covered gondola cars to a permanent off-site disposal facility
operated by Envirocare of Utah, Inc., in Tooele County, Utah. Of this
total, 2,100 tons were contaminated with metals as well as radioactive
material. A Supplemental Standards Report, prepared in March 1994,
documented radiological contamination that remained on site at OU4.
Materials left in place are located at 500 South Santa Fe Drive
(ROBCO); and the Burlington Northern Railroad ROW immediately east of
ROBCO (OU4).
Pursuant to the terms of the Agreement and Covenant Not To Sue
(July, 1995; also called the Prospective Purchaser Agreement (Home
Depot PPA), Home Depot USA (Home Depot) placed a restrictive covenant
on OU4. The restrictive covenant restricts future use of the areas
where radiological contamination was left in place under supplemental
standards. In addition, Denver's zoning ordinance and its radium fee
ordinance provide ICs generally at properties in OU 4/5 where radium-
contaminated soil remains in place under supplemental standards. Also,
the PPA provides additional ICs for this operable unit.
OU6, OU9A, OU11
Remedial Action operations at OU6, OU9A, and OU11 included the
following:
Excavation of radium-contaminated soil;
The analysis of the contaminated materials to ensure
compliance with transportation and disposal regulations;
Shipment of contaminated materials to the permanent off-
site disposal facility; and
Confirmation sampling of excavated area.
Remediation was conducted in phases to facilitate the cleanup and
to accommodate the various business activities within these operable
units. Remediation began in March 1989 and was completed in December
1993. During the Remedial Action for OU6, OU9A, and OU11, 8,336 tons of
contaminated soil were excavated and disposed off site.
118 tons of contaminated soil were excavated from a property at
South Pecos Street and West Arizona Avenue and disposed off site. The
excavated area was backfilled with clean soil and re-vegetated. Various
properties within OU6, OU9A and OU11 also were remediated and a total
of 5,365 tons of material were excavated for off-site disposal. A total
of 2,403 tons of contaminated soil was excavated from the Environmental
Materials, Inc. (EMI) and Regional Transportation District properties.
This soil was transported by rail to the permanent disposal facility in
Utah. In 1993, during the final phase, 450 tons of contaminated soil
were excavated from the EMI property and transported by rail to the
permanent disposal facility in Utah. Even though the 1995 ESD spoke
about supplemental standards applying to OU6, all contamination was
subsequently removed, thus, institutional controls are not required.
OU7
The EPA selected remedy combines features of excavation and
disposal with the modified no action alternative. This remedy entails:
Leaving the contaminated material in place;
Improving ICs so that all routine maintenance, repair and
construction activities in the affected streets by government agencies,
utility companies, contracting companies, and private individuals will
be monitored; and
[[Page 54787]]
Removing any contaminated material excavated during
routine maintenance, repair, or construction activities in the affected
streets to a facility approved for storage or disposal of contaminated
material.
Due to the location, nature, and volume of radioactive
contamination at OU7, the modified no action alternative was
implemented at this operable unit. The potential routes of human
exposure to the radioactivity are limited since the contaminated
material is bound in the asphalt and is not free to move in any
direction. None of the streets are near surface water or groundwater
resources and the material has little potential for erosion or leaching
because the contaminated aggregate is bound in the asphalt matrix
within the pavement cap. Thus, the contamination in the asphalt matrix
does not pose a threat to human health or the environment if left
undisturbed.
The City and County of Denver has been actively managing the radium
materials for many years. This active management served as the ICs for
this operable unit. Due to the effort, requiring annual training for
city and utility workers and the financial commitment, the City and
County of Denver opted to ensure long-term public health and safety by
removing the contaminated material from these streets in OU7. This
action included the removal of asphalt and any contaminated road base
and fill material.
As part of the Denver Radium Streets Program, between 2003 and 2007
Denver removed contamination from the following properties: South
Bannock Street; 11th Avenue from Race Street to Josephine; Marion
Street from 6th Avenue to 10th Avenue; Humboldt Street from 7th to 9th
Avenue; Lafayette Street from 1st Avenue to 10th Avenue; Downing Street
from 7th to 10th Avenue; 9th Avenue from Ogden to Franklin Street;
Corona Street from 7th to 10 Avenue; Park Avenue West from Arapahoe to
California Street; York from 6th to 13th Avenue. In addition, the
Denver Streets portion of OU3, Jason Street, was remediated in 2007. As
a result of these actions, there is no waste left in place within
Operable Unit 7, and ICs are not required.
OU8
The initial Remedial Action at OU8 was substantially completed in
September 1998. Remedial Action at OU8 included the following:
Demolition of radium-contaminated buildings;
Excavation of radium-contaminated soil from vicinity
properties, Bannock Street, the storm sewer located east of Santa Fe
Drive, and the Shattuck Chemical property;
On-site stabilization/solidification of the radium-
contaminated soil into a disposal cell;
Capping of the stabilized material; and
Installation of monitoring wells to evaluate the
effectiveness of the remedy.
The Remedial Action at OU8 was conducted in two phases, beginning
September 1992, and was substantially complete in September 1998.
During Phase I approximately 67,345 tons of building debris were
disposed off site and 8,700 cubic yards of soil were excavated from the
vicinity properties. During this phase, approximately 200 cubic yards
of asbestos containing material were removed and disposed under
appropriate regulations. Approximately 400 cubic yards of
radiologically contaminated material were excavated from beneath
Bannock Street. Stabilization/solidification of the radiologically
contaminated material began in July 1996 and was completed in November
1997.
Approximately 65,000 loose cubic yards of radiologically
contaminated soil excavated from Shattuck Chemical and the vicinity
properties were stabilized/solidified on site in a disposal cell.
Capping of the stabilized material was completed in June 1998. ICs were
implemented through a Declaration of Covenants and Restrictions, filed
with the City and County of Denver on March 25, 1999, that restricted
surface and groundwater use.
During the excavation of radiologically contaminated soil, oil-
impacted soil also was found on site. The materials were below the
action levels established in the ROD. Approximately 2,000 cubic yards
of oil-impacted soil were excavated from the Shattuck Chemical Property
located at 1805 South Bannock Street during Phase 2 activities. This
material was covered and transported by truck to Conservation Services,
Inc. in Thornton, Colorado. Bioremediation was used for oil-impacted
soil that extended beneath the completed portion of the monolith. A
plan addressing the remaining oil-contaminated soil at OU8 was
submitted in August 1998. The bio-venting system was approved by EPA
and was installed in September 1998.
In 1997, the storm sewer along Santa Fe Boulevard west of the site
was remediated. During the remediation, an in-situ form liner was
installed into the original pipe to isolate storm water discharges to
the South Platte River from the influx of contaminated groundwater.
This liner system, while in place, did not remedy the problem. In 1998,
the sewer remediation was investigated by EPA and the City of Denver
and determined to be incomplete. The City and County of Denver
installed a new sewer cutoff that has significantly limited the amount
of potential infiltration into the sewer line along Bannock Street. A
management plan for OU8 Bannock Street was developed and adopted in
March 1999 by the City and County of Denver to govern all maintenance,
repair, or other construction activities at OU8 Bannock Street.
In 1999, the EPA conducted a discretionary five-year review of the
monolith and found deficiencies in the cover design and the structural
and chemical integrity of the structure. EPA concluded that it could
not assure the long-term protectiveness of this remedy. The June 2000
amended ROD required removal of 100,000 cubic yards of the material and
full cleanup of the site. Groundwater quality will continue to be
monitored until performance standards are met; therefore, the
groundwater is not part of this partial deletion.
EPA began to remove the contaminated soil and monolith in March
2003 to U.S. Ecology, a permitted facility in Grandview, Idaho. Waste
shipments began on March 9, 2003. A total of 243,872 tons of
contaminated soil and materials was removed by the fall of 2006. The
site has been verified to be clean and restored. Clean excavation and
fill material was backfilled into all open areas where the
contamination was removed and has been returned to grade. The covenant
restricting surface and groundwater use was later modified to remove
the surface use restrictions.
The Amended Declaration of Covenants and Restrictions was filed in
2007. However, there are still elevated levels of contaminants in
groundwater including uranium, arsenic, cadmium, selenium, molybdenum,
and gross alpha and gross beta radioactivity. In addition to the
restrictive covenant, a restriction notifying each well permit
applicant about the potential for contamination in the groundwater was
placed July 17, 2006 on OU8 through the Colorado Office of the State
Engineer.
OU9B
The Remedial Action at OU9B (ROBCO Metals) was completed in three
phases, beginning in October 1995 and completed in April 1996. During
Phase 1 activities, the ROBCO Site was prepared for the excavation,
movement and consolidation of heavy metal contaminated soil. During
Phase 2 activities, the existing ROBCO Building/
[[Page 54788]]
Plant foundation was demolished and the area of contamination outside
the Area of Consolidation was excavated. Approximately 62,062 cubic
yards of material were excavated and/or moved during Phase 2 of the
Remedial Action. During Phase 3 activities, the Area of Consolidation
cap was constructed, the identification barrier was installed, and
structural fill was placed and compacted to final design grade and
contour.
In accordance with the Home Depot PPA, Home Depot, USEPA, and CDPHE
performed closure of the Robinson Brick Company in a defined ``shared''
and ``phased'' manner. Home Depot submitted a Draft O&M Plan on May 30,
1997. CDPHE and EPA approved the O&M Plan on March 17, 1998. Based on
the O&M Plan, EPA and CDPHE will perform biannual, off-site groundwater
monitoring and Home Depot will perform biannual inspections of store
facilities and site utilities.
The restrictive covenant that Home Depot recorded for OU 4/5 waste
also covers the OU 9B heavy metal contamination. The restrictive
covenant prohibits disturbance of the Area of Consolidation and
prohibits use of groundwater.
The Home Depot PPA requires that any breaches of the soil cap
system over the Post-Consolidation Area of Contamination will be
reported to EPA and CDPHE with the requirement that new construction,
remodeling and site repair generally will not be conducted in this
area.
OU10
Remediation activities at OU10 began in September 1988 and ended
September 22, 1989. A total of 15,021 tons of materials with depths
raging from 0 to 80 inches was removed and was disposed off site at
Envirocare of Utah.
No extensive changes were made to the major structures on the
property, although several small structures were removed and not
replaced at the request of the owner. Some un-assessed contamination
required removal, but the volumes were not large.
Cleanup Standards
For radiological contamination, EPA calculates risk based on area
averaging of several measurements over 100 square meters. When these
calculations are below the EPA surface standard of less than 5 pCi/g
above background and below the subsurface standard of 15 pCi/g above
background, the area is considered safe for unlimited use and
unrestricted exposure as long as soil at depth with 15 pCi/g above
background remains at depth.
Operation and Maintenance
The City and County of Denver have agreed to implement a management
plan for radium-contaminated soil remaining in place in Denver's
rights-of-way and to continue to enforce Denver's zoning ordinance and
its radium fee ordinance as ICs at private properties where radium-
contaminated soil remains in place under supplemental standards. The
management plan and ordinances provide ICs wherever supplemental
standards apply across the Site. Specifically, these institutional
controls apply to waste left in place at Operable Units 2, 3, and 4.
In addition to the Denver management plan and ordinances, EPA has
agreements in place with owners of other operable units whereby those
owners have agreed to manage waste left in place and provide
institutional controls. These additional controls include limitations
on the use of groundwater at OUs 8 and 9B. Those operable units are
described below.
OU2
Pursuant to the terms of a settlement agreement, the current owner
of the Umatilla property, formerly DuWald property, Atlas Umatilla,
LLC, has prepared an O&M Plan and signed and executed an environmental
covenant on June 25, 2006. The environmental covenant restricts
disturbance of the concrete cap and subsurface soil. In addition,
indoor air quality will be monitored.
OU4/5 & 9B
Pursuant to the terms of the Home Depot PPA, Home Depot prepared an
O&M Plan and placed a restrictive covenant on OU4. The restrictive
covenant restricts future use of the areas where wastes were left in
place, including the area of consolidation of metal wastes and the
radioactive waste left in place under supplemental standards. Home
Depot has an amended O&M Plan as of August 18, 2003.
Five-Year Reviews
Remedial actions which result in any hazardous substances,
pollutants, or contaminants remaining on site will be subject to
statutory five-year reviews. The purpose of a five-year review is to
evaluate the implementation and performance of a remedy to ensure that
the remedy is and remains protective of public health and the
environment.
The first five-year review was completed in September of 1993,
triggered by remedial actions at OU 4/5. The first five-year review
addressed OU 4/5 only. The following year, a site-wide review was
completed on September 12, 1994. No modifications or improvements to
the remedy were suggested in these first two reviews.
A discretionary five-year review, conducted in 1999 for OU8 only,
identified concerns with the long-term effectiveness of the on-site
remedy. The remedy was modified in 2000, and remediation was completed
in 2006.
Another site-wide five-year review was completed in 2003. This
review identified (1) deficiencies in ICs at three OUs and (2) new
requirements for risk assessments where waste was left in place under
supplemental standards. ICs have since been implemented and the risk
assessments were revised. No modifications to the selected remedies
were required.
The 2008 Five-Year Review identified a few issues, however none of
them affected current or future protectiveness. The review found that
because the remedial actions at all OUs are protective, the Site is
protective of human health and the environment.
Since waste is left in place, five-year reviews will continue
indefinitely to ensure continued protectiveness of the remedies. The
next statutory five-year review is scheduled September 2013.
Community Involvement
EPA's Community Relations Plan involved the community in the
decision process for selecting all remedies for the Denver Radium Site
and promoted communications among interested parties throughout the
duration of the project.
Community relation's activities included:
Briefing State and local officials, public interest
groups, neighborhood associations, interested citizens, and media
representatives on the status of the various phases of the project,
Conducting public meetings to keep citizens informed of
the progress of the Denver Radium Site project and to solicit comments,
Establishing information centers at the Denver Public
Library and the EPA's Denver Superfund Records Center to make available
for public review the study reports, site air-monitoring data,
supplemental assessments, and other Denver Radium Site information,
Maintaining a mailing list of interested parties and
distributing information updates to those parties during the Remedial
Action phases,
Organizing a committee of representatives from citizen
groups, State and local governments, EPA, DOE, USBR, and the
transportation contractor
[[Page 54789]]
to provide input to the transportation and disposal activities
associated with the Denver Radium Site,
Informing communities along the transportation route,
through meetings and mailings, of health and safety issues associated
with waste transportation,
Distributing news releases to the major news media in
affected areas.
Public participation activities have been satisfied as required in
CERCLA section 113(k), 42 U.S.C. 9613(k), and CERCLA section 117, 42
U.S.C. 9617. Documents in the deletion docket which EPA relied on for
recommendation of the deletion from the NPL are available to the public
in the information repositories.
Determination That the Criteria for Partial Deletion Have Been Met
In accordance with 40 CFR 300.425(e), Region 8 of the EPA finds
that the Denver Radium Superfund Site meets the substantive criteria
for partial NPL deletions, with the exception of groundwater at OU8.
Groundwater contamination associated with OU8 will remain on the NPL.
EPA has consulted with and has the concurrence of the State of
Colorado. All responsible parties or other persons have implemented all
appropriate response actions required. All appropriate Fund-financed
response under CERCLA has been implemented, and no further response
action by responsible parties is appropriate.
V. Partial Deletion Action
The EPA, with concurrence of the State of Colorado, through the
Colorado Department of Public Health and Environment, (in a letter
dated January 2, 2008) has determined that all appropriate response
actions under CERCLA, other than operation, maintenance, monitoring and
five-year reviews, have been completed. Therefore, EPA intends to
delete from the NPL each of the 11 OUs at the Denver Radium Site.
Groundwater contamination associated with OU8 will remain on the NPL.
These remedies ensure protection of human health and the
environment by minimizing exposure to any radium-contaminated or heavy
metals contaminated soil that remain within the Denver Radium Superfund
Site. Therefore, EPA is deleting the above properties from the NPL.
Because EPA considers this action to be noncontroversial and
routine, EPA is taking it without prior publication. This action will
be effective November 8, 2010 unless EPA receives adverse comments by
October 12, 2010. If adverse comments are received within the 30-day
public comment period, EPA will publish a timely withdrawal of this
direct final Notice of Partial Deletion before the effective date of
the partial deletion, and it will not take effect. EPA will prepare a
response to comments and continue with the deletion process on the
basis of the Notice of Intent for Partial Deletion and the comments
already received. There will be no additional opportunity to comment.
List of Subjects in 40 CFR Part 300
Environmental protection, Air pollution control, Chemicals,
Hazardous waste, Hazardous substances, Intergovernmental relations,
Penalties, Reporting and recordkeeping requirements, Superfund, Water
pollution control, Water supply.
Dated: August 31, 2010.
James B. Martin,
Regional Administrator, Region 8.
0
For the reasons set out in this document, 40 CFR part 300 is amended as
follows:
PART 300--[AMENDED]
0
1. The authority citation for part 300 continues to read as follows:
Authority: 33 U.S.C. 1321(c)(2); 42 U.S.C. 9601-9657; E.O.
12777, 56 FR 54757, 3 CFR 1991 Comp., p.351; E.O. 12580, 52 FR 2923,
3 CFR 1987 Comp., p.193.
Appendix B--[Amended]
0
2. Table 1 of Appendix B to part 300 is amended by revising the entry
under Colorado for ``Denver Radium Site'', ``Denver'' to read as
follows:
Appendix B to Part 300--National Priorities List
Table 1--General Superfund Section
----------------------------------------------------------------------------------------------------------------
State Site name City/county Notes (a)
----------------------------------------------------------------------------------------------------------------
* * * * * * *
Colorado............................... Denver Radium Site........ Denver.................... P
* * * * * * *
----------------------------------------------------------------------------------------------------------------
(a) A = Based on issuance of health advisor by Agency for Toxic Substances and Disease Registry (if scored, HRS
score need not be > 28.50).
* * * * * * *
* P = Sites with partial deletion(s).
* * * * *
[FR Doc. 2010-22489 Filed 9-8-10; 8:45 am]
BILLING CODE 6560-50-P