I
~ Collection
jurce Center
l 19107
. United States
Environmental Protection
Agency
Office of
Emergency and
RemedieJ Response
EPA/ROD/R08-87/014
September 1987
3EPA
Superfund
Record of Decision:
~8~-172I7b
Denver Radium/Open Space, CO
U.S. Environmental Protection Agency
Region III Iniormation Resource.
Center (3PM52) o' ~
841 Chestnut Stree~ ./ .,.:.;',~
..,...~J."'~
Philadelphia, PA !910l ."i~~
- .
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TECHNICAL REPORT DATA
(Pftllst ,tlld Instructions on tht ,tvtnt btfCNt com"lttinl)
1. RE'ORT NO. 12. 3. RECIPIENT'S ACCESSION NO.
~A/ROD/R08-87/014
. ITL.E AND SU8TITL.E 5. REPORT DATE
SUPERFUND RECORD OF DECISION September 29, 1987
Denver Radium/Open Space, CO 8. PERFORMING ORGANIZATION CODE
Seventh Remedial Action
7. AUTHORISI 8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS 10. PROGRAM EL.EMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS 13. TYPE OF REPORT AND PERIOD COVERED
U.S. Environmental Protection Agency Final ROD Report
401 M Street, S.W. 1.. SPONSORING AGENCY CODE .
washington, D. C. 20460 800/00
15. SU"L.EMENTARV NOTES
18. ABSTRACT
T~e Denver Radium site, located in Denver, Colorado, consists of more than 40
contaminated properties. These properties have been grouped into eleven operable
units. This operable unit consists of eleven Denver Radium properties in an indust;ria1
'se area, which are known collectively as Open Space properties. Three of the
:operties lie within the designated 100-yea~ flood plain. In 1979 EPA noted a
reference to the National Radium Institute (NRI) in the 1916 Bureau of Mines report.
This reference revealed the presence of 31 radioactive sites in the Denver Metropolitan
area. In 1913 the NRI was established in Denver as a domestic source of radium which
was in high demand as a wonder drug for the treatment of cancer. Su'::>sequent1y, the
Denver radium, vanadium and uranium industry thrived until the early 1920s when rich
deposits of ore were discovered in Africa. Records indicate that one source of
contamination at the Open Space properties results from the radium, vanadium and uraniun
processing conducted by the National Radi~m Corporation, Radium Company of Colorado,
Schlesinger Radium Company and Rocky Mountai~ Radium Products Company. Additionally the
Allied property, a 21.5-acre portion of the Open Space properties site, contains
contaminated fill brought in from an unknown construction site in the early 1960s. The
Brannan property, a 47.5-acre portion of the site, is suspected to contain radiological
hospital waste. Other sources of radioactive materials present at the site have not
(See Attached Sheet)
17. KEV WORDS AND DOCUMENT ANAL.YSIS
.. DESC,.IItTORS b.IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Croup
Record of Decision
Denver Radium/Open Space, CO
Seventh Remedial Action
Contaminated Media: so i1, ai r, debris
Key contaminants: radium and associated
. decay products
OlSTRI8UTION STATEMENT 19. SECURITV CL.ASS IT/lis R~po") 21. NO. OF PAGES
None 51
20. SECURITY CL.ASS IT/lis pagt) 22. PRice
None
e,. "'111 2220-1 (Rn. 4-77)
P"EVIOUI EOITION II OB'OLETE
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EPA/ROD/R08-87/014
Denver Radium/Open Space, CO
Seventh Remedial Action
16.
ABSTRACT (continued)
been determined. Although presently no serious public health risk from radon decay
product/exposure exists, a significant increase in risk could occur if the contaminated
materials were to be misused or inadvertently spread.
The selected remedial action for this site includes: onsite temporary containment
(capping) of approximately 4,320 ft2 (29G yd3) of contaminated material followed by
offsite permanent disposal consisting of cap removal, excavation and offsite
transportation: and removal of approximately 1,020 yd3 of material with plaqement in
containers and offsite disposal at the Card Corporation Property, until an offsite
permanent disposal facility becomes available. At that time, the temporary storage
facility on the Card Corporation property will be decontaminated and, if necessary,
dismantled and disposed of at an offsite solid waste disposal facility. The estimated
present worth cost for this remedial action is $955,400, which includes 5-year O&M.
~ -
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DECLARATION
FOR THE
RECORD OF DECISION
Site Name
Open Space Properties
Operable Units VI, IX, and XI
Denver Radium Site
'Site Location
Various locations throughout metropolitan area
Denver, Colorado
Statement of Pur~05e
This decision document presents the selected-remedial
actions for the properties included in Operable Units VI, IX, and
XI of the Denver Radium Site developed 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 the National Contingency
Plan (40 CFR Part 300). '
The State of Colorado has concurred on the selected
remedies. (See attached letter.)
Statement of Basis
This decision is based upon the administrative record for
the Open Spac~ properties, Operable Units VI, IX, and XI of ' the
Denver Radium Site. The attached index identifies the items
which comprise the administrative record upon which the selection
of the remedial actions was based.
Descriotion of the Selected Remedies
This is the seventh Record of Decision for the Denver Radium
Site. The hazardous substances of primary concern that have been
released and continue to be released into the environment at the
Denver Radium Site properties are radium. and its associated decay
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2
products. Long-term exposure to radium and its decay products
has been shown conclusively to increase the risk of contracting
lung cancer.
This Record of Decision addresses the contamination present
on Operable Units VI, IX, and XI of the Denver Radium Site.
Operable Unit VI is comprised of the following properties:
- Allied Chemical and Dye Corporation (Allied)
- Brannan Sand and Gravel (Brannan) .
- Colorado and Southern Railroad (CSRR)
- Denver Water Department (DWD)
- Public Service Company (PSCo)
- Ruby Hill Park
- Alley between Mariposa and Lipan Streets
Operable Unit IX includes the International House of
Pancakes (IHOP) and Larry's ,Trading Post and East Side ~musement
Center (Larry's). Operable Unit XI consists of the Thomas Real
Estate Company (Thomas Realty) property. These properties are
known collectively as the Open Space properties. EPA's selected
remedy for each of the Open Space properties is described below.
Allied property:
EPA's preferred remedial action alternative for the Allied
property is Offsite Permanent Disposal. However" until a
facility suitaple for permanent disposal of the Open Space
properties material is designated and, if nec~ssary, acquired and
developed, this alternative cannot be implemented. Pursuant to
CERCLA Section 104(c)(3)(C)(ii), it is the responsibility of the
State of Colorado to'assure the availability of a facility for
offsite disposal of the Open Space properties material. Although
both the EPA and State of Colorado are continuing to seek a '
permanent disposal site, the State estimates that this process
could take up to five years. Given the length of time which may
pass before the State assures the availability of an offsite
permanent disposal facility, and in order to prevent or minimize
the threat to public health and the environment, the EPA has.
determined that a remedial action alternative which includes
temporary response actions should be implemented at the Allied
property.
EPA has therefore determined that the appropriate extent of
remedy at the Allied property is Onsite Temporary Containment
(Capping), Offsite Permanent Disposal. This remedial action
alternative will attain a degree of cleanup of the hazardous
substances which will assure both short-term and long-term
protection of human health and the environment. The present-
worth cost of the selected remedy for the Allied property is
$143,600 based upon a ten-percent interest rate, a five-year
discount period, and a perpetual monitoring period. The selected
remedial action alternative for t~e Allied property entails:
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3
placing a cap over the identified areas of
contamination which cover approximately 4,320 square
feet of the Allied property;
maintaining the cap on the Allied property until a
facility suitable for the permanent disposal of Open
Space properties material becomes available; and
excavating the contaminated material from under the cap
and transporting the material to the offsite permanent
disposal facility.
Remedial Design for the Allied property w~ll include the
selected remedy and EPAts preferred remedial action alternative,
Offsite Permanent Disposal. Should the State of Colorado fulfill
its obligation to assure the availability of a suitable disposal
facility for material from the Open Space properties by the time
EPA has concluded Remedial Design for the Alli~d property, the
EPA may implement its preferred alternative, Offsite Permanent
Disposal.
Brannan.property, Ruby Hill Park, and the Alley:
EPA's selected remedy for the Brannan property, Ruby Hill
Park and the alley is No Action. According to the Remedial
Investigation, it does not appear that the radium contamination
in soils on these properties exceeds the target residual levels
established in contaminant-specific ARARs for the Open Space
properties. None of these properties would be eligible for
cleanup under the inclusion criteria developed to implement the
contaminant-specific ARAR, 40 CFR Part 192.
In the case of the alley, EPA makes the following
. recommendations:
1. That the City and County of Denver improve existing
institutional controls so that all routine maintenance,
repair, or construction activities in the alley carried out
by government agencies, utility companies, contracting
companies, private individuals, etc., will be monitored; and
2. That the City and County of Denver consider removing or
requiring the removal of any contaminated material exca~ated
during routine maintenance, repair, or construction
activities in the alley to a facility approved for the
storage or disposal of such contaminated material.
EPA believes these recommendations will more successfully be
carried out if the alley is included in the institutional
controls program for Streets, Operable Unit VII of the Denver
Radium Site. The City and County of Denver is developing these
institutional controls under a cooperative agreement with the
State of Colorado. EPA has already awarded Superfund Cooperative
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4
Agreement funds for this purpose and consistent with CERCLA
Section 104(c)(3), the State of Colorado and the City and County
of Denver will be responsible for assuring the payment of all
future costs of maintaining and operating the institutional
controls, including proper disposal of any contaminated material
excavated during routine maintenance, repair, or construction
activities in the alley.
Data on the Brannan property, Ruby Hill Park, and the alley
will be reviewed during Remedial Design of the Open Space
properties, and if necessary, additional data will be collected
to confirm that the target residual levels are not being
exceeded. If EPA determines that the costs of additional
, sampling for this purpose would exceed the costs of cleanup, or
if the review indicates that target residual levels are exceeded,
a remedial action alternatiye other than No Action may be
implemented at these properties.
In the case of the Brannan property and the alley, Onsite
Temporary Containment (Capping), Offsite Permanent Disposal, will
serve as the backup alternative. If future data evaluation
indi,cates that contaminant-specific ARARs are being exceeded at
Ruby Hill Park, or if the costs of additional sampling to make a
,determination exceed the costs of cleanup, then Temporary
Building Storage at Card Corporation Property (OU X), Offsite
Permanent Disposal, will be implemented at the Park.
The present-worth cost of the selected remedy for 'Ruby Hill
Park , depends upon whether future data evaluation indicates that
contaminant-specific ARARs are exceeded, resulting in the backup
alternative being implemented. If instead of No Action,
Temporary Building Storage at Card Corporation Property (OU X),
Offsite Permanent Disposal, is implemented at Ruby Hill Park, the
present worth cost would be $92,900.
The present worth cost'of the selected remedy for the
Brannan property and the alley depend upon whether future data
evaluation indicates that contaminant-specific ARARs are'
exceeded, resulting in the backup alternatives being implemented.
If instead of No Action, Onsite Temporary Containment (Capping),
Offsite Permanent Disposal, is implemented at the Brannan
property, the present worth cost would be $68,500. If this
remedial action alternative is implemented at the alley, the
present-worth cost would be $41,000.
CSRR, DWD, PSCO, IHOP and Larry's, and Thomas Realty properties:
The EPA preferred alternative for these properties is
Offsite Permanent Disposal. However, as described above, until a
facility suitable for permanent dispo~al of the Open Space
properties material is designated and, if necessary, acquired and
developed by the State of Colorado, this alternative cannot be
implemented. EPA has therefore determined that the appropriate
extent of remedy for these properties is Temporary Building
"
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5
Storage at Card Corporation Property (OU X), Offsite Permanent
Disposal. This remedial action alternative will provide both
short-term and long-term protection of public health and the
environment.
The selected remedial action alternative for the CSRR, DWD,
PSCo, rEOP and Larry's, and Thomas Realty properties entails:
cleanup of these properties and storage of the
contaminated material from these properties in the
temporary storage facility on the Card Corporation
property, Operable Unit X of the Denver Radium Site;
maintaining the temporary storage facility at the Card
Corporation property until a facility suitable for the
permanent disposal of Denver Radium Site wastes becomes
available; and
final removal of the contaminated material from the
Card Corporation property and transport to the offsite
permanent disposal facility.
The present worth cost of the selected remedy for these
properties is as follows:
CSRR
DWD
PSCo
rEOP
Larry's
Thomas
$126,800
150,600
94,000
130,700
93,600
147,600
The costs are based upon a ten-percent interest rate, a
five-year discount period, and a perpetual monitoring period.
Remedial Design for these properties will include the
selected remedy and EPA's preferred remedial action alternative,
Offsite Permanent Disposal. Should the State of Colorado fulfil
its obligation to assure the availability of a suitable disposal
facility for material from the Denver Radium Site by the time EPA
has concluded Remedial Design for these properties, the EPA may
implement its preferred alternative, Offsite Permanent Disposal.
Operation and maintenance activities will be required to
ensure the effectiveness of the temporary response actions
associated with the selected remedies for the Open Space
properties. These activities include site inspections, ongoing
radiological monitoring, and possible minor repairs to the cap on
the Allied property or the temporary storage facility on the Card
Corporation property. Also included as an operation and
maintenance activity for cost estimating purposes is a review of
the properties which, pursuant to SARA Section 121(C), must be
conducted no less than every five years if a remedial action is
selected that results in any hazardous substances remaining'
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6
onsite. Since EPA does not anticipate that any hazardous
substances will remain onsite longer than five years, the
this review is considered a contingency. Operation and
maintenance costs for each property are included with the
worth total alternative costs mentioned above.
cost of
present
Declarations
Consistent 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 the National Contingency Plan (40 CFR Part 300), I have
determined that the selected remedies for the Open Space
properties, Operable Units VI, IX, and XI of the Denver Radium
Site, are protective of human health and the environment, attain
Federal and State public health and environmental requirements
that are applicable or relevant and appropriate, and are cost-
effective. The remedies utilize permanent solutions and
alternative treatment technologies to the maximum extent
practicable. Even though the remedies do not satisfy the
statutory preference for treatment which reduces the toxicity,
mobility, and volume of hazardous substances as its principal
element, the remedies address the principal threat at the
properties. Treatment was determined to be impracticable based
upon effectiveness, technical feasibility,-implementability, and
cost factors.
9-P
J~ J. Scherer
Regional Administrator
EPA Region VIII
,~
. d2. ~ / ~ 1'7
Date
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RECORD OF DECISION
SUMMARY
Site Name
Open Space Properties
Operable Units VI, IX, and XI
Denver Radium Site
.
Site History
Shortly after radium was discovered by Marie Curie" in 1898,
it gained enormous popularity as the miracle remedy for a wide
variety of ailments, especially cancer. Consequently, the demand
for the element increased dramatically through the early 1900s.
Prior to 1914, the processing of radium-bearing ore was
conducted exclusively in Europe. The onset of World War I,
however, caused a growing concern in the United States that
European exportation of radium might be interrupted. This
concern led to the establishment of the National Radium Institute
in 1913. The National Radium Institute successfully developed
and operated a radium processing plant in Denver.
Denver was chosen as the location of the National Radium
Institute facility"due to its proximity to the Colorado Plateau,
which contained rich deposits of the radium-bearing ore,
carnotite. Soon numerous operations opened in Denver to process
ore for radium, vanadium, and uranium. However, during the early
1920s, the availability of less expensive radium from foreign
countries forced most of the Denver producers to abandon their
operations. .
. Much of the radiological contamination present on the Open
Space properties, Operable Units VI, IX, and XI of the Denver
Radium Site, i.s believed to be either the direct result of radium
and uranium processing on the property or the result of
processing wastes being transported to the property from a
processing site.
Response History
In 1979, EPA noted a reference to the National Radium
Institute in a 1916 United States Bureau of Mines report.
Subsequent field research revealed the presence of thirty-one
radioactive sites in the Denver metropolitan area,. several of
which are now part of the Open Space properties of the Denver
Radium Site (Figure 1). Immediately after identifying these
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FIGURE 1
LOCATION MAP
OP:N SPAC; ?ROP:RTIES
OE!'4VER RAOIUM SiTE
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3
properties, the Radiation Control Division of the Colorado
Department of Health officially notified the affected property
owners of the presence of radiological contamination on their
properties. The letters requested that no excavation or soil
movement be undertaken without first contacting the Division.
In August, 1981, the Colorado Department of Health, under a
cooperative agreement with EPA, assumed lead activities and
initiated engineering assessments of the majority of the original
31 properties. In October, 1981, shortly after the cooperative
agreement was awarded to the State, the Denver Radium Site was
placed on the Interim Priorities List. The Site was included on
the Final National Priorities List promulgated on September 8,
1983.
EPA resumed Fund-lead activities in June, 1983, because the
Colorado State Legislature failed to appropriate the state cost
share for remedial planning required by EPA at the time. In
December, 1983, EPA directed its contractor to conduct a Remedial
Investigation (RI) of the Denver Radium Site to determine the
nature and extent of the contamination present 'on those
properties which the State did not previously study plus several
contiguous properties where additional contamination was
suspected. EPA also directed its contractor to conduct a
Feasibility Study (FS) of each operable unit to evaluate proposed
remedies for the contamination present on all of the Denver
Radium Site properties which, with the addition of the contiguous'
properties, totalled over 40 properties.
Because of the enormity and complexity of the Denver Radium
Site, EPA determined that response actions undertaken in operable
units would be cost-effective and consistent with a permanent
remedy for the entire Denver Radium Site. Thus, the original
Denver Radium Site properties plus the contiguous properties
where contamination was discovered subsequent to the initial
listing of the site on the Interim Priorities List were divided
into eleven operable units, the Open Space properties being
Operable Units VI, IX, and XI. The properties were divided based
primarily upon site conditions and proximity to other Denver
Radium Site properties.
In April, 1986, the Denver Radium Site Remedial
Investigation Report, which addresses all eleven operable units,
was released to the public. The draft Open Space Properties FS
was released for public review on August 14, 1987. Responses to
comments received during the public comment period are contained
in the Responsiveness Summary attached to this Record of
Decision. The final Open Space Properties FS is comprised of the
draft Open Space Properties FS incorporating the changes
described in the errata. Pursuant to SARA Section 104(i),
draft Open Space Properties FS was submitted for review by
Agency for Toxic Substances and Disease Registry (ATSDR).
signing of this Record of Decision, ATSDR had not formally
responded. However, preliminary discussions with ATSDR indicated'
that ATSDR'had no major criticisms of the report.
the
the
At the
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4
Site Location and Description
The Denver Radium Site, located in Denver, Colorado,
(population 509,000) consists of more than 40 contaminated
properties. These properties have been grouped into operable
units. Operable 'Unit VI is comprised of the following
properties:
- Allied Chemical and Dye Corporation
- Brannan Sand and Gravel
- Colorado and Southern Railroad
- Denver Water Department
- Public Service Company
- Ruby Hill Park
- Alley between Mariposa and Lipan Streets
Operable Unit IX includes the International House of
Pancakes (IHOP) and Larry's Trading Post and East Side Amusement
Center (Larry's). Larry's is a contiguous property sometimes
referred to as Contiguous Property No.8 (CP No.8). Operable
Unit XI consists of the Thomas Real Estate Company (Thomas
Realty) property. These properties are known collectively as the
Open Space properties.
Since the RI was init~ated, ownership of several of the
properties has changed. The Allied Chemical and Dye Corporation
property is currently owned by General Chemical , the Colo,rado and
Southern Railroad property is presently owned by Burlington
Northern Railroad, and the Thomas Realty property is now owned by
Commercial Investors Realty. For the purpose of this Record of
Decision, however, the original names will be used.
The Allied Chemical and Dye Company (Allied) property covers
an area of 21.5 acres and is located at 1271 West Bayaud Avenue.
The property is bound on the northeast by the South Platte River,
on the southwest by a railroad, and on the south by West Bayaud
Avenue. The north end of the property is leased to Denver Wood
Products (Figure 2). The Allied property is primarily open land
with occasional trees, roadways, railroad tracks, and paved
areas. There are approximately ten structures onsite and
currently nine employees working 40 hours per week on the
property. There are no buried municipal utilities in
contaminated areas of the site, although 13 kilovolt overhead
lines are present along the northern and northwestern perimeters
of the property. The property is zoned I-1 for industrial use.
The Brannan Sand and Gravel (Brannan) property is a 47.5-
acre parcel that lies between Clear Creek and 61st Avenue about
300 feet east of Federal Boulevard (Figure 3). The property
contains approximately 10 acres of open land which became a
municipal dump in the early 1960's. When the dump was closed in
,1982, it contained 10 to 15 feet of refuse and was being covered
with construction debris. The Brannan property is currently
zoned I-1 for industrial use. There are no buried municipal
utilities on the property.
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ALLIED PROPERTY
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8AANNAN PROPERTY
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7
The Colorado and Southern Railroad (CSRR) property is bound
to the northeast and southwest by 16th Street and 15th Street,
respectively, by Platte River Drive to the northwest, and by the
South Platte River to the southeast (Figure 4). A buried
concrete conduit parallels the CSRR right-of-way and is
approximately 50 feet from the river bank. No other buried
municipal utilities have been identified on the property. The
railroad tracks on the property are not currently in use, .
although both the tracks and the right-of way are maintained.
The CSRR property is zoned 1-1 for industrial use.
The Denver Water Department (DWD) owns a 0.1-acre lot near
the corner of Yuma Court and 12th Avenue (Figure 5). This lot is
paved and is presently used as a parking lot for neighboring
businesses. The east end of the lot is bordered by a paved alley
and the west end by Yuma Street. A 54-inch concrete water main
tending roughly east-west bisects the lot. The lot is currently
zoned 1-1 for industrial use.
The Public Service Company of Colorado (PSCo) owns a vacant
lot adjacent to its South Substation at south Pecos Street and
West Arizona Avenue (Figure 6). A residential area lies to the
west of the lot on South Pecos Street. Surface drainage on the
property runs from topographic highs along the north and south
boundaries towards the center of the lot where a large east-west
tending gully is located. The property is zoned 1-1 for
industrial use and several four-inch water mains are buried on
the .property. Several overhead 13 kilovolt transmission lines
cross the western portion of the property.
Rpby Hill Park is an active city park bound by West Jewell
Avenue, South Pecos Street, West Florida Avenue, and South Platte
River Drive (Figure 7). The park covers an area of approximately
90 acres and is bordered by a residential area on the South Pecos
Street side. The park is characterized by rolling, open terrain
with the only significant structure being a one-story maintenance
building. There are four baseball fields on the property as well
as a network of paved roadways and parking areas. There are no
buried utility lines in the park.
The alley between Mariposa and Lipan Streets extends from
5th Avenue to 6th Avenue and underneath the 6th Avenue overpass
(Figure 8). A metal scrap storage yard lies to the east of the
alley, while an automobile salvage operation and a stove products
company are situated to the west. A one-story brick apartment
building is located at the northeast corner of the intersection
of the alley and the 6th Avenue right-of-way. The apartments are
unoccupied except for one unit. There are buried municipal
utilities in the alley.
The 1HOP property is located at 2001 East Colfax Avenue
(Figure 9). The site covers 0.38 acre and consists of a
restaurant and a paved parking. lot. The property is bound on. the
south by East Colfax Avenue, on th~ north by residences, on the
west by Race Street, and on the east by Larry's. The IHOp.
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PROPERTY
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OWD PROPERTY
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FIGURE 6
PSCo PROPERTY
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It lOP AND CP NO.8 PROPERTIES
EXTENT Of CONTAMINATION
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1 4.
restaurant is a two-story building that operates 24 hours a day.
The restaurant employs approximately 15 people who are divided
into three work shifts. Buried water lines are present on the
IHOP property and the property is 'zoned B-4 for general business
use. Larry's, which shares a driveway and parking lot with IHOP,
is a single-story structure which houses an arcade, pool hall,
snack bar, and a used clothing store. The number of occupants of
this building varies.
The Thomas Realty property is a triangular shaped, 1.25-
acre lot located at 1285-1295 South Santa Fe Drive. The property
is bordered by South Platte River Drive on the northwest, by
South Santa Fe Drive on the east, and by Desks, Inc., a
commercial establishment on the south (Figure 10). A two-story,
building is situated on the southern portion of the Thomas
-property. The building is currently occupied by. 13 people for
40 hours per week. A billboard is located on the northern end of
the property. Approximately 30, 30-gallon drums, filled with
radium-contaminated soil excavated from the property by the
previous owner, are stored beneath the billboard. Natural gas
and water lines are buried on the property. .
The majority of the Open Space properties are underlain by
alluvium and the Denver formation sandstone. The approximate
depth to ground water ranges from five feet at the DWD property
to 75 feet at Ruby Hill Park. Three of the properties, Allied,
Brannan, and DWD, lie within the designateQ 100-year flood plain.
Property-specific information on underlying geology, depth to .
ground water and bedrock, and location within. a flood plain is
contained in Table 2-1 of the Open Space Properties FS. The
climate of the Denver area is typified by low annual
precipitation averaging about 14 inches per year.
Current Site Status
Radium and its associated decay products are the primary
contaminants of concern at the Open-Space properties. Since
gamma radiation readings in excess of background may indicate the
presence of radium, a gamma radiation survey was used to outline
the extent of possible radium contamination on the Open Space
properties. (Areas of contamination are noted on Figures 2
through 10.) Gamma radiation readings in excess of background
were found over 16,902 square feet of the Open Space properties.
Average gamma radiation measurements ranged from 7 microroentgen
per hour (pR/hr) to 239 pR/hr above background. The maximum
gamma radiation measurement was 1,900 ~R/hr above background and
was taken at the CSRR property. (A general discussion of
radiation and its associated units of measurement is presented in
Appendix A of the Open Space Properties FS and in the Public
Health and Environmental Assessment, Appendix B of the Open Space
PropertiesFS. )
The presence of radium in the soil was verified by
radiochemical analysis of subsurface soil samples from each of
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16
the Open Space properties except the Brannan property, Ruby Hill
Park, and the alley. The volume-weighted average radium
concentration in the contaminated soils on the Open Space
properties is 101 picocuries per gram (pCi/g). The average
radium concentrations found on the properties ranged from
8.2 pCi/g to 244 pCi/g. The maximum radium concentration was
found on the CSRR property and was 2,775 pCi/g. The maximum
depth of radium contamination found on the properties was
56 inches at IHOP. The estimated total volume of radium
contaminated soil on the Open Space properties is 1,380 cubic
yards. Table 1 and Figures 11 and 12 summarize the volume, area,
and depth of contamination and the gamma radiation and radium
concentration data collected on the Open Space properties.
Only a few structures are present on the Open Space
properties. EPA has no reason to suspect that the majority of
these buildings contain elevated concentrations of radon decay
products, elevated gamma radiation readings, or alpha
radioactivity contamination. EPA or the Colorado Department of
Health conducted tests in IHOP, Larry's, and the building on the
Thomas Realty property and determined these buildings to be free
of contamination. These conclusions are subject to verification
during Remedial Design. The State of Colorado was refused entry
to the building adjacent to the CSRR property. EPA will
determine if this building is contaminated during Remedial
Design. .
On those Open Space properties where samples were taken, the
radium concentration in the soils exceeded the target residual
levels established in the "EPA Standards for Remedial Actions at
Inactive Uranium Processing Sites," 40 CFR Part 192, which EPA
has determined are relevant and appropriate Federal requirements
for the Open Space properties. These standards are discussed
later in this summary in the section entitled "Statutory
Determinations".
Certain Open Space properties, Allied and CSRR, were
investigated for nonradiological contamination because of known
historical industrial uses ot the particular property. Figures
2-3 and 2-5 of the Open Space Properties FS show sampling
locations on the Allied and CSRR properties, respectively, and
Tables 2-4, 2-5, 2-8, and 2-9 of the Open Space Properties FS
present the results. A small number of polynuclear aromatic
hydrocarbons (PAHs) were found on both the Allied and CSRR
properties. There are no standards for PAHs in soil to which
these levels can be compared. One sample collected on the Allied
property exceeded the Extraction Procedure (EP) toxicity limits
for lead and mercury as specified in Table 1, 40 CFR
Section 261.24.
The elevated concentration of radium and the uncontrolled
state of the soils on the Open Space properties pose a health
hazard due to ~hree principal potential exposure pathways. In
order of decreasing significance, they are: (1) inhalation of
radon gas, the immediate decay product of radium, and radon's own
-------
17
Tabl'e 1
St.1U" ACZ A.'II) St.'3St~ ACZ CON':.U'.1..'iA::CN
OP!:.'f S?ACZ i'ROP::''-I''''~, C!.,{VE."~ R..\lm:~1 S:::;:
C-==a ~c~at~on a Est~ted a.di~ CQnce~t~~t~on
Vo~~e Area ('..:."./!'::-) te;:1th (::c!..I~)
LOC3t~on (va") 1!E.:l Ave:'3~e ~"t:..:\:: (~::.) Ave:'3£e :-..a...~:':1..:
All1ea 293 4,320 U9 :is '8 J,l. 34
:0 198 198
22 U6 136
3ra.nnan U 200 60 107 :'S :fA 1\.\
CSM. 207 2,800 231 1,900 2to 2to3.5 2,i7S
t_i:) 309!) 1,;CO 239. seo N.A 5.: 18.7
PSCQ 18 32.5 NA NA O-lS 37 54
Jluby E111 10.b 4 Sl 51 NA NA NA
Alley :fA 115 19 29 NA NA NA
a :;0. 8 (A) l.l 100 7 8 36 ll2.6 . 4.25.5
lEO? (3) 198 1,145 12 62 0-56 17.2 7to.l
~cm.as (A.,) US 1,lSl 31 76 36 w.s 690
..
I:1cm.a.s (A-) ~ 5.:12 15 83 12 79.1 l.:J
'"
:cuI. 1,379 16,902 ~..u: S6
"alues ~nver:ea for purrose of .co=~ar~son. !hese values are less
presented ~ !aole :-2,'as a~su:ptiocs wera :aee in ~onversions.
bzst~ated volu:ej no dep~ value obtaiced !or this area.
acc~ra:e than ~~ose
Notes:
NA . ~ata not available or not recoreed for this area.
~ gamma is ~~ gr~d scan gac:a. C.~ read~gs are co~ec:ed ~eadir.gs
above bacltground. (apprax:i=.ately lS \,I..:t/t1r for the Denver area).
Areas given are based on elevatea ga=:a ~ead.~gs. Volumes are calculated
usi.~1 c1ept.~s f:'olll c::e 196: ea s::J.C17, u.cept for c:.e ~c:::as' ?roper:y, which
used. c1ept:s ::'c: ::8 1985 E:4 s~~y, and.' t:::e ~CP ar.d. a No. 8 p~ope:'~~es,
"'nere ~e area oi c:ontaminat~on was de:~ed usi.~1 ~ot..~ !:he 1982 Cli stuay anc1
the 1985 ~.A. s~ciy. .'bere a range oi c1ept:.s i.s given, the m.a..~U:II c1ep:.'t is
usee to calculate t.."Ie volume. If a volu::e is g1.,en w1c1l depth aoe: available,
l:.:1e volee ~as bee:1 cuen ~~:'ec:ly f=oc c:e C; study. I:1e :atiol".ale for c:e
volu:e for Ruby aill 1.1 pre.sec:aci ~ c:e :ax:.
Lccat~on.s 0: c:ontamL~ation can te found. ~ Fi~=es 2-2 th=ough
2 - !..S_.
-------
18
Figure 11
AUERAGE AND MAHIMUM GAMMA RADIATION MEASUREMENTS
OPEN SPACE PROPERTI ES
DENUER RAD I UM SITE
1'900~~
H~BOO
280
260
240
220
200
180 ~ AUERAGE
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19
Figure 12
AUERRGE AND MRHIMUM RRDIUM CONCENTRRTIONS
OPEN SPACE PROPERTIES
DENUER RAD I UM SITE
2'775~N.
425~ .- 690
R
n
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-------
20
short-+ived decay products, (2) direct gamma radiation exposure
from the decay of radium and its progeny, and (3)" ingestion or
inhalation of radium-contaminated materials. Since radium is in
a form that is relatively insoluble, and since migration of
radiological contaminants into the ground water or surface water,
where it exists, has not been noted, ingestion or contact with
contaminated ground water or surface water are not among the
principal potential exposure pathways. Each of the three
principal exposure routes resulting from the radium contamination
on the Open Space properties will be discussed briefly in terms
of the potential health risks associated with that exposure
route. In addition, the health risks associated with ingestion
of the nonradiologically contaminated soil present on the Allied
and CSRR properties will be discussed.
Inhalation of Radon Decay Products:
Radon gas and its decay products present the greatest health
risk from long-term exposure. Radon gas decays to a series of
short-lived particulates which are typically electrostatically
charged at their formation and often attach themselves to .
airborne particles. If these contaminated particles are inhaled,
then the lungs and other internal organs are exposed to the
highly ionizing sub-atomic particles which the radon decay
products emit. Prolonged inhalation of air with a high
concentration. of radon decay products has been conclusively shown
to cause increased occurrence of lung cancer in uranium miners.
Dispersion quickly dilutes radon emanating from radium-
contaminated ground. This mechanism will minimize the radon
concentration in the air above the Open Space properties to such
an extent that no one working on or living near the properties is
presently at risk from exposure to radon and its associated decay
products from this source. Radon decay products can concentrate
to unacceptable levels in bUildings built over contaminated
ground if those buildings are energy efficient, that is, have
little exchange of indoor air with outdoor air. EPA has no
information that any of the limited number of structures present
on the Open Space properties exhibit elevated concentrations of
radon decay products.
Although there is no known present public health risk from
radon decay product exposure at the Open Space properties,.EPA
has determined that a significant increase in public health risk
would occur if any of the contaminated material on the properties
is spread closer to potential receptors, especially if it is used
as fill or construction material, or if the properties are ever
redeveloped for any use that involves occupancy in enclosed,
energy-efficient structures. The Public Health and Environmental
Assessment for the Open Space properties, summarized below and
contained in Appendix B of the Open Space Properties FS, presents
projected cancer risks if EPA were to take no action at the
properties and the properties were redeveloped in any of these
ways. . .
-------
21
If a building were constructed over the CSRR property, the
most contaminated of the Open Space properties, and several
conservative assumptions are made (such as lifetime exposure),
the estimated radon decay product concentration in such a
building would average 1.46 WL. The radon decay product
concentration in a typical United States home is 0.005 WL and the
relevant and appropriate EPA standard, 40.CFR Part 192, is
0.02 WL. The average projected cancer risk (excluding
background) to individuals working in such a building ranges from
1,400 to 4,200 cancer deaths per 10,000 persons exposed. The
average projected cancer risk to individuals living in such a
building ranges from 4,700 to 7,800 cancer deaths per 10,000
persons exposed.
These risk yalues can be compared to the average projected
cancer risk if the radon decay product concentration in the
building was 0.02 WL, the EPA standard. In this case, the
average projected cancer risk to individuals working in such a
building ranges from 23 to 91 cancer deaths per 10,000 persons
exposed. The average projected cancer risk to individuals living
in such a building ranges from 130 to 500 cancer deaths per
10,000 persons exposed. If the radon decay product concentration
in the building was that of a typical United States home,
0.005 WL, then the average projected cancer risk to individuals
living in the building would range from 33 to 130 cancer deaths
per 10,000 persons exposed. It should be noted that these
projected cancer risk numbers do not include the EPA-estimated
spontaneous risk of lung cancer, that is, the risk not
attributable to either smoking or radon.. Table 2 presents the
information stated above.
Gamma Radiation Exposure:
The radioactive decay of radium and its decay products
results in the emission of highly penetrating gamma radiation.
Gamma radiation is of concern because it can easily penetrate a
few centimeters of soil to give anyone standing over a
contaminated area a reasonably uniform irradiation over the whole
body. The greater the duration or intensity of this exposure,
the larger the dose, and hence the greater the risk of adverse
health effects. In ~he case of the Open Space properties, the
gamma radiation emission is limited to the area immediately above
the contamination.
As discussed previously, EPA has determined that a
significant increase in public health risk would result if any of
the contaminated material on the Open Space properties was
disturbed and misused or if any of the properties were
redeveloped. If a building was constructed over the CSRR
property, the most contaminated of the Open ~pace properties, the
estimated annual dose to a person working in such a building
would average 464 millirem per year (mrem/yr) with an estimated
maximum annual dose of 3,819 mrem/yr. The estimated annual dose
to a person living in such a building built over the CSRR
property would average 1,518 mrem/yr with an estimated maximum
-------
Scenario
Radon Decay Products:
Building constructed
over CSRR
EPA Standard*
Typical U.S. Home
Gamma Radiation:
Building constructed
over CSRR .
EPA Standard*
Bal:k ground
22
Table 2
PROJECTED CANCER RISKS
OPEN SPACE PROPERTIES
DENVER RADIUM SITE
Average
Exposure
Average Cancer Deaths
Per 10,000 Persons Exposed
1. 46 WL Work place 1400 to 4200
Res i den t i a 1 4700 to 7800
0.02 WL Work place 23 to 91
Res i den t i a 1 1 30 to 500
0.005 WL Residential 33 to 130
231 uR/hr Workplace 79**
Residential 330**
20 uR/hr Workplace 31**
Residential 53**
15 uR/hr Residential 27
* 40 CFR Part 192
** In addition to risk from exposure to background gamma radiation levels.
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annual dose of 12,480 mrem/yr. These doses are in addition to
the background dose of 130 mrem/yr incurred by those living in
the Denver area and resulting from cosmic, terrestrial, and
internal sources. The National Council on Radiation Protection
and Measurements (NCRP) and the International Commission on
Radiological Protection (ICRP) recommend a maximum allowable
whole-body gamma radiation dose of 100 mrem/yr for members of the
public in addition to natural background radiation and medical
exposures they receive. .
The projected cancer risk from gamma radiation (including
background) to individuals working in such a building built over
the CSRR property would average 79 cancer deaths per 10,000
persons exposed. The projected cancer risk to individuals living
in the building would average 330 cancer deaths per 10,000
persons exposed. If individuals in any building were to receive
a lifetime gamma radiation dose equivalent to that of the
relevant and appropriate EPA standard, 40 CFR Part 192, then the
projected cancer risk to those working in the building would
average 31 cancer deaths per 10,000 persons exposed and the
projected cancer risk to those living in the building would
average 53 cancer deaths per 10,000 persons exposed. The average
projected cancer risk to individuals receiving a lifetime dose
resulting from the Denver area background would be 27 cancer
deaths per 10,000 persons exposed. It should be noted that
cancer risks resulting from gamma radiation exposure are in
addition to those resulting from inhalation of radon decay
products. Table 2 presents the information stated above.
Inhalation or Ingestion of Radiologically Contaminated Material:
Inhalation of the long-lived radionuclides like uranium,
thorium, and radium is possible for persons living or working on
or near the Open Space properties. Airborne particulate matter
may contain small concentrations of these radionuclides resulting
in a potential human exposure pathway. Inhalation or direct.
ingestion of long-lived radionuclides can result in significant
doses to various internal organs of the body. However, studies
by the United States Department of Energy have shown that the
projected radiation doses from this source are many times smaller
than those estimated for either radon decay product inhalation or
direct gamma radiation exposure using even the most conservative
assumptions. Also, it is unlikely that a person would ingest.
large amounts of the radium-contaminated material on the Open
Space properties and dust control measures ordinarily employed
during excavation have been shown to provide sufficient control
of exposure from this source. For these reasons, EPA
acknowledges the human exposure pathway resulting from inhalation
and ingestion of radionuclides, but no quantitative risk numbers
were developed in the Public Health and Environmental Assessment
for the Open Space properties.
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Ingestion of Nonr~diologically Contaminated Soil:
The Public Health and Environmental Assessment quantifies
risk to human health from ingesting soil containing low-levels of
certain nonradiological carcinogenic contaminants which were
found in discrete locations on the Allied and CSRR properties.
For the Allied property, the average projected cancer risks from
this type of exposure range from 0.034 to 0.10 cancer deaths per
10,000 persons exposed. For the CSRR property, the average
projected cancer risks from this type of exposure range from
0.046 to 0.079 cancer deaths per 10,000 persons exposed. These
risks are several orders of magnitude lower than the estimated
risks resulting from exposure to the radiological contamination
on the property. Nonetheless, the presence of nonradiological
contaminants on the site will be explicitly considered in all
health and safety provisions of the cleanup.
In summary, it is clear that a release or substantial threat
of release of a hazardous substance or pollutant or contaminant
into the environment has occurred at the Open Space properties
and the release or threat of release may present an imminent and
substantial endangerment to public health. It is also clear from
the calculated risks. that remedial action at the majority of the
Open Space properties is justified. .
Enforcement
A detailed responsible party search for the entire Denver
Radium Site has been initiated. Regarding the source of
.contamination on the Open Space properties, records show the
following. The radium-contaminated soil present on the CSRR
property is apparently the result of a radium, vanadium, and
uranium processing operation conducted by the National Radium
Corporation, which occupied the property in 1926 and 1927.
Radiological contamination on the DWD property is believed to be
related to a facility operated by Radium Company of Colorado
which was located on the nearby DuWald Steel property (an
Operable Unit II property). Schlesinger Radium Company, a
predecessor of the Radium Company of Colorado, operated a lab at
2001 East Colfax Avenue, the present day location of IHOP. The
contamination present on Thomas Realty is suspected tQ have
resulted from processing conducted by Rocky Mountain Radium
Products Company. The responsible party search has yet to trace
any of these companies or any associated companies to a viable,
- present-day entity.
Radium-contaminated material on the Allied property is
thought to be contaminated fill that was brought in from an
unknown downtown construction site during the early 1960s. The.
radiological contamination present at. the Brannan property is
suspected to be hospital waste. The sources of the radioactive
materials present on the remaining Open Space properties have not
been determined.
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At this time, the responsible party search has not revealed
that the present owners of the Open Space properties have any
record of having been connected with the activities that caused
their respective properties to be contaminated. EPA does not
feel that response actions should be delayed pending finalization
of the responsible party search. If, upon finalization of the
search, responsible parties are clearly identified for a
property, EPA will formally notify them of the selected remedy
for that property and initiate negotiations for the
implementation of the remedy. If the responsible parties do not
formally commit to performing the remedy in a timely manner, EPA
will proceed with a Fund-financed remedial design and remedial
action and will attempt to recover EPA's response costs from the
responsible parties.
Community Relations History
On August 13, 1987, the Proposed Plan for the Open Space
properties was published in the Denver Post. On August 14, 1987,
the Proposed .Plan was published in the Rocky Mountain News. The
display ads announced the August 14 through September 4, 1987,
public comment period and the August 26 public meeting, gave a
brief description of the remedial action alternatives, and stated
the rationale for the Proposed Plan.
In addition to publishing the Proposed 'Plan, EPA issued a
press release announcing the public comment period. The press
release, along with the Executive Summary of the Open Space
Properties FS, was mailed to the approximately 300 names on the
EPA-compiled Denver Radium Site mailing list.
On August 7, 1987, EPA scheduled a meeting with the owners
and tenants of the Open Space properties to describe and discuss
the cleanup alternatives being considered for the properties.
The owners and tenants who attended the meeting were interested
in the details of remedial action, in particular, how. remedial
action activities would affect their business operations and if
they would be compensated for any loss of business.
On August 26, .1987, EPA held a public meeting concerning the
Open Spa.ce properties. Major concerns raised by those who'
attended the meeting were similar to those raised at the owners
and tenants meeting, that is, how remedial action activities at
the properties would affect the business operations of the owners
and tenants and if they would be compensated for any loss of
business. A second major concern raised at the public meeting
was the liability of owners of contaminated properties. Another
major concern raised during the public meeting was a question of
why remedial action is so costly.
In. general, the public supports the complete excavation and
permanent offsite disposal of all Denver Radium Site material.
including the contaminated material" present on the Open Space
properties. The community has reservations about any temporary
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response action which EPA may take at the Open Space properties
because of concerns that the State of Colorado will not make
available a permanent disposal site for this material and
therefore, no permanent measures will ever be implemented at the
Open Space properties. In addition, certain elected officials
voiced concerns about selecting the No Action Alternative at some
of " the properties, in particular, Ruby Hill Park. The portion of
the community in the vicinity of the Card Corporation property
(See Figure 1) strongly opposes temporary storage of Open Space
property material at the Card Corporation property, Operable Unit
X of the Denver Radium Site, again because of concerns that the
State of Colorado will not make available a permanent disposal
site and that the temporary storage facility on the Card
Corporation property will become permanent, resulting in a
decrease in property values in the area.
The Responsiveness Summary attached to the Record of
Decision contains the official transcript of the public meeting,
describes in more detail the nature and level of the community's
concern, and includes EPA's responses to all comments received
during the public review of the Open Space Properties FS.
Alternatives Evaluation
EPA evaluated potential remedial action alternatives for .the
Open Space properties primarily by progressing through the series
of analyses which are outlined in the National Contingency Plan
(NCP), in particular, 40 CFR Section 300.68; the Interim Guidance
on Superfund Selection of Remedy, December 24, 1986, (OSWER
Directive No. 9355.0-19); and" the Additional Interim Guidance for
FY '87 Records of Decision, July 24, 1987, (OSWER Directive
No. 9355.0-21). This process, in part, enables EPA to address
the SARA Section 121 requirements of selecting a remedial action
that is protective of human health and the environment, that is
cost-effective, that attains Federal and State public health and
environmental requirements that are applicable or relevant and
appropriate, and that utilizes permanent solutions and
alternative- treatment technologies or resource recovery
technologies to the maximum extent practicable. Additionally,
SARA Section 121 and the guidance documents referenced above
"require EPA to give preference to remedies which employ treatment
which permanently and significantly reduces the toxicity,
mobility or volume of hazardous substances as their principal
element.
The selection of remedy process begins by identifying
certain site-specific information to be assessed in determining
the types of response actions that will be considered for the
properties. A general list of site-specific information to be
considered in the process is contained in Section 300.68(e)(2) of
" the NCP. This list was used to identify specific site and waste
characteristics of the Open Space properties. (See Tables 5-1
and 5-2 of the Open Space Properties FS.) Based upon these site
and waste characteristics, EPA was able to scope, .from the
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27
universe of all possible response actions, a set of r~sponse
actions and associated technologies to be considered for the Open
Space properties. An example of this scoping process was the
elimination from further consideration of onsite reprocessing on
certain Open Space properties because these particular properties
do not have sufficient area to construct a reprocessing facility.
Appendix D of the Open Space Properties FS illustrates the
scoping process and Table 5-3 of the Open Space Properties FS
details the results.
Section 121(b)(1) of SARA requires that an assessment of
permanent solutions and alternative treatment technologies or
resource recovery technologies that, in whole or in part, will
result in a permanent and significant decrease in the toxicity,
mobility, or volume of the hazardous substance, pollutant, or
contaminant be conducted. As part of this process, EPA evaluated
permanent solutions to the problems associated with the specific
hazardous substances present on the Open Space properties. The
alternative treatment and resource recovery technologies
considered included, among others, in-situ vitrification and
reprocessing. .
Before the technologies were assembled into remedial action
alternatives, they were categorized as either source control or
management-of~migration measures and then pre screened based on
their suitability to abate the threat at the Open Space
properties. Source control measures are intended to contain the
hazardous substances onsite or eliminate the potential for
contamination altogether by transporting the hazardous substances
to a safer location. Management-of-migration actions are taken
to minimize and mitigate the migration of hazardous substances.
The result of the prescreening of both source control and
management-of-migration measures based on their suitability to
abate the threat at the Open Space properties is presented in
Taple 5-4 of the Open Space Properties FS.
The next step of the selection of remedy process is
assembling the remaining technologies and/or disposal options
into remedial action alternatives. Pursuant to OSWER Directive
No. 9355.0-19, "Interim Guidance on Superfund Selection of
Remedy", remedial action alternatives are to be developed ranging
from those that would eliminate the need for long-term management
(including monitoring) at the site to alternatives involving
treatment that would reduce toxicity, mobility, or volume as
their principal element. Remedial action alternatives developed
in this way will vary mainly in the degree to which they rely on
long-term management of treatment residuals or low-concentration
wastes. Further, a.containment option involving little or no
treatment and a no action alternative are to be developed.
Remedial action alternatives developed in the Open Space
Properties FS were:
1 .
No Action (Allprope~ties)
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28
2 0
Deferred Removal, Offsite Permanent.Dispo$al (All
properties)
3.
Onsite Reprocessing/Treatment, Offsite Permanent
Disposal (Allied and Brannan properties)
In-Situ Vitrification (Allied and Brannan properties)
4.
5.
Onsite Permanent Disposal (Allied, Brannan, and PSCo
properties)
Offsite Permanent Disposal (All properties)
6.
7 .
Onsite Temporary Land Storage, Offsite Permanent
Disposal (Allied, Brannan, PSCo, and Thomas Realty
properties)
8.
Onsite Temporary Building Storage, Offsite Permanent
Disposal (Allied, Brannan, PSCo, and Thomas Realty
properties)
Onsite Temporary Containment (Capping), Offsite
Permanent Disposal (All properties)
9.
Temporary Building Storage at the Card Corporation
Property (OU X), Offsite Permanent Disposal (All
properties)
Alternatives 2, 3, 6, 7, 8, 9, and 10, since they require
the permanent offsite disposal of contaminated material, would
eliminate the need for long-term management (including
monitoring) at the Open Space properties. Alternatives 3 and 4
involve treatment as their principal element, but do not
necessarily reduce the mobility, toxicity, or volume of the
waste. Alternatives 4 and 5 require permanent onsite remedies,
and hence, long-term management and monitoring at the Open Space
properties. Alternatives 5, 7, 8, and 9 are containment options
- Alternative 5 requiring permanent onsite containment and
Alternatives 7, 8, and 9 requiring temporary onsite containment.
Finally, No Action was included as Alternative 1.
Alternative 6, Offsite Permanent Disposal, is not
immediately implementable because the State of Colorado has not
at this time designated a facility for the disposal of the Denver
Radium Site wastes. Pursuant to CERCLA Section 104(c)(3)(C)(ii),
it is the responsibility of the State to assure the availability
of a disposal site. Also, in order to comply with SARA Section
104(k), and.in order to assure that remedial actions within
Colorado continue, the State must provide adequate assurance of
the availability of a hazardous waste treatment or disposal
facility within three years fro~ the effective date of SARA,
October 17, 1986. Although progress is being made to this end,
the Sta~e does not expect to have a fully operational disposal
facility prior to implementation of the remedial a~tiQn and for
up to five years. In the meantime, in its presently uncontrolled
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29
state, the radium-contaminated material at the Open Space
properties could be misused or inadvertently spread, possibly
increasing the risk to present or future public health or the
environment. In addition, ,the cost of final remedial action is
expected to increase due to inflation; the Open Space property
owners and tenants face economic losses associated'with
restricted use of their properties; and EPA may incur further
cost by updating site studies in face of changing site
conditions. For these reasons, EPA determined that, in order to
effectively mitigate or minimize short-term threats to and
provide adequate protection of public health and the environment
at the Open Space properties, developing remedial action
alternatives which include temporary response actions was
appropriate. Thus, Alternatives 7, 8, 9, and 10 were developed
to reduce existing risks by including temporary response measures
followed by permanent offsite disposal of the contaminated
material when a facility for such disposal becomes available.
Initial screening, which is the next step in the selection
of remedy process, narrows the list of potential remedial action
alternatives. Consistent with Section 300.68(g) of the NCP and
the OSWER Directive No. 9355.0-19, the remedial action
alternatives developed for the Open Space properties were
initially screened using the criteria of cost, implementability
(acceptable engineering practices), and effectiveness. Table 7-1
in the Open Space Properties FS summarizes the initial screening
process. Alternatives 1, 2, 7, 8, 9, and 10 passed the initial
screening and were carried forward for detailed analysis while
Alternatives 3, '4, 5, and 6 were screened out primarily for the
reason~ set forth below.
Alternative 3, Onsite Reprocessing, which due to site
conditions was only being considered for the Allied and Brannan
properties, was eliminated from further consideration based on
its lack of effectiveness. The residuals from this process, both
the reprocessed soil and the concentrated precipitate resulting
from the reprocessing ~f the soil, would require disposal in a
facility that meets or exceeds the requirements of 40 CFR
Part 192. These residuals would retain many of the toxicity and
mobility characteristics of the untreated material and, in
addition, the volume would not be significantly affected. This
remedial action alternative would provide no additional benefit
to public health or the environment over other remedial action
alternatives to be considered.
Alternative 4, In-Situ Vitrification, which due to site
conditions was only being considered for the Allied and Brannan
properties, was eliminated during the initial screening because
its implementability and effectiveness for this particular
application is unproven. In-situ vitrification has not been
demonstrated on a large scale or utilized in highly-populated
urban areas like that of the Allied or the Brannan properties.
cap qver the vitrified areas would be necessary to limit the
escape of radon gas and; thus, this alternative does not affect
toxicity or persistence of the contaminated material.
A
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Furthermore, the Allied and Brannan properties would each have to
be permanently dedicated as a disposal site and measures would
have to be taken to prevent human contact with or disturbance of
the vitrified material on both of the properties. Finally, this
remedial action alternative would require long-term government
ownership, licensing, management, and monitoring to protect the
integrity of each cap and vitrified mass. These requisites would
conflict with current and proposed land uses for the properties,
as well as State policies on siting permanent disposal
facilities, (6 CCR 1007-1, Part III, Schedule E, Criterion 1).
The State siting objectives specify, among other things, that
permanent disposal facilities must be located away from populated
areas and that hydrogeologic and other environmental conditions
be conducive to continued immobilization and isolation of
contaminants from usable ground water sources. These criteria
are clearly not met at the Allied and Brannan properties which
are located within a metropolitan area, and where at the Allied
property, for example, the depth to ground water is only
approximately 10 feet.
With the elimination of these two remedial action
alternatives, no remedial action alternative which involves
treatment as a principal element survives the initial screening.
However, EPA has no reasonable belief that either of these
remedial action alternatives are equally protective as other
remedial action alternatives, .or of.fer the potential for better
treatment performance or implementability, lesser adverse
impacts, or lower costs than demonstrated remedial action
alternatives.
Alternative 5, Onsite Permanent Disposal, which due to site
conditions was only being considered for the Allied, Brannan, and
PSCo properties, was eliminated from further consideration
because of implementability and effectiveness factors. Each
property would have to be permanently dedicated as a disposal
site and measures would have to be taken to isolate the
contaminated material from man and the environment for a thousand
years without ongoing active maintenance. This objective would
be difficult to attain in an urban area where there is a high
potential for human disturbance and in an area where the ground
water is fairly close to the surface as it is on these
properties. This remedial action alternative would require' long-
term government ownership, licensing, and management and
monitoring to protect the integrity of each facility. These
requisites would conflict with current and proposed land uses for
the properties, as well as State policies on siting permanent
disposal facilities (6 CCR 1007-1, Part III, Schedule E,
Criterion 1) discussed above.
Alternative 6, Offsite Permanent Disposal, which was being
considered for all properties, is not implementable at this time
because the State of Colorado has yet to designate a facility for
the disposal of Denver Radium Site wastes. This alternative was
therefore eliminated during initial screening.
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The following is.a description of the remedial action
alternatives surviving the initial screening:
1 .
No Action (All properties)
If this remedial action alternative were selected, no
action would be taken at the contaminated Open Space
properties. This alternative serves as a baseline and
was retained for further analysis and consideration as
required by Section 300.68(f)(1 )(v) of the NCP.
2.
Deferred Removal, Offsite Permanent Disposal (All
properties)
If this remedial action alternative were selected,
removal of the contaminated material at the Open Space
properties.would be deferred until an approved offsite
permanent disposal facility is identified and. made
available by the State of Colorado. Once this facility
becomes available the contaminated material on the Open
Space properties would be excavated and transported by
either truck or rail for final disposal at this
facility. The Open Space properties would then be
available for unrestricted use.
7.
Onsite Temporary Land Storage, Off site Permanent
Disposal (Allied, Brannan, PSCo, and Thomas R~alty
properties)
If this remedial action alternative were selected,
contaminated material on the Allied, Brannan, PSCo, and
Thomas Realty properties would be excavated and
temporarily stored on each property, respectively. An
asphalt pad would be constructed on an open area of
each property. Contaminated material from each
property would be placed on the pads and covered with a
suitable material. Security precautions, inspections,
and radiation monitoring of the land-storage facilities
would be instituted. Once a suitable offsite permanent
disposal facility becomes available, the contaminated
material from each property would be transported by
either rail or truck to the facility. The Allied,
Brannan, PSCo, and Thomas Realty properties would then
be available for unrestricted use.
8.
Onsite Temporary Building Storage, Offsite Permanent
Disposal (Allied, Brannan, PSCo, and Thomas Realty
properties)
.If this remedial action alternative were selected,
contaminated material on the Allied, Brannan, PSCo, and
Thomas Realty properties would be excavated and placed
in conta~ners. The containers would be temporarily
stored in a newly constructed building on each'
. property. Security precautions, inspections, and
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32
radiation monitoring of the storage facilities would be
instituted. Once a suitable offsite permanent disposal
facility becomes available, the contaminated material
would be transported by either rail or truck to the
facility. Upon removal of the containers, the
buildings would be decontaminated and either dismantled
or left in place. The Allied, Brannan, PSCo, and
Thomas Realty properties would then be available for
unrestricted use.
9.
Onsite Temporary Containment (Capping), Offsite
Permanent Disposal (All properties)
If this remedial action alternative were selected, the
identified areas of contamination on each Open Space
property would be capped. Some of the Open Space
properties, such as IHOP and the alley, already have
asphalt caps in place. Restrictions on excavation
would be required to limit disturbance of the caps.
Security precautions, inspections, and radiation
.monitoring of the caps would be instituted. Once a
suitable offsite permanent disposal facility becomes
available, the contaminated material from each property
. would be transported by either rail or truck to the
facility. The Open Space properties would then be
available for unrestricted use~
10.
Temporary Building Storage at Card Corporation Property
. (OU X), Offsite Permanent Disposal (All properties)
If this remedial action alternative were selected, the
identified areas of contamination on each Open Space
property would be excavated, the material placed in
containers, and the containers transported to the Card
Corporation Property (OU X) for temporary storage. The
Open Space properties would then be available for
unrestricted use. Security precautions, inspections,
and radiation monitoring of the temporary storage
facility on the Card Corporation property would be
instituted. Once a suitable offsite permanent disposal
facility becomes available, the contaminated material
would be transported by either rail or truck to the
facility. The Card Corporation property would then be
available for unrestricted use.
Consistent with Section 300.68(h) of the NCP, the OSWER
Directive No. 9355.0-19, and the OSWER Directive No. 9355.0-21,
the remedial action alternatives remaining after initial
~creening were further refined and then subjected to detailed
analysis. Detailed analysis of each remedial action alternative
entailed evaluation based on the three broad criteria of
implement~bility, effectiveness, and cost. For each of these
broad criteria, EPA.identified appropriate and more specific
. "component measures" so that the remedial action alternatives
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33
could be compared to each other using a full array of evaluation
factors. The component measures derived for implementability,
effectiveness, and cost were based upon specific requirements and
criteria contained in Section 300~68(h)(2) of the NCP, SARA.
Sections 121(b)(1 )(A through G), SARA Section 121(C), the
discussion on detailed analysis contained in the OSWER Directive
No. 9355.0-19, and the OSWER Directive No. 9355.0-21.
The component measures of implementability are: technical
feasibility, constructability, reliability, administrative
concerns, availability of the technology, and operation and
maintenance. The component measures of effectiveness are
attainment of applicable or relevant and appropriate requirements
(ARARs); effectiveness in significantly and permanently reducing
mobility, toxicity, and volume; persistence, toxicity, mobility,
and propensity to bioaccumulate of the hazardous substances and
their constituents; protectiveness/health effects; environmental
protectiveness/potential for adverse environmental impacts; and
compliance with the Solid Waete Disposal Act. The component
measures of cost are: capital cost, operation and maintenance
costs, and potential future remediation' costs if the alternative
fails. Section 8 of the Open Space Properties FS provides a
comparative review of the remedial action alternatives based upon
each of the component measures listed above.
Implementability Analysis:
Ali of the alternatives vhich were analyzed in detail are
technically feasible and constructable, are relatively easy to
implement since they rely on readily available earth moving and
construction technologies, and are operationally reliable.
Removal of materials from around buried utilities will require
special precautions. Each remedial action alternative except No
Action and Alternative 2, Deferred Removal, Offsite Permanent
Disposal, requires a limited degree of maintenance activities.
No Action and Alternative 2 are administratively the easiest
alternatives to implement. The need to coordinate and obtain
access agreements with the Open Space property owners and the
need to obtain necessary approvals and non-environmental
const~uction permits from other offices and agencies are
administrative implementation constraints common to all of the
remedial action alternatives with the exception of No Action.
Alternative 10, Temporary Building Storage at Card Corporation
Property (OU X), Offsite Permanent Disposal, has an additional
administrative implementation constraint, that is, an agreement
with the Mentor Corporation, current owner of the Card
Corporation property, to allow for storage of other Denver Radium
Site wastes on the property must be finalized.
The necessary equipment and specialists for implementation
of any of the remedial action alternatives are readily available.
Remedial action work similar to that envisioned in the remedial
action alternatives is already being safely conducted in Grand
Junction, Colorado, under the auspices of the Uranium Mill
T~ilings remeaial acti6n Project. The final response actidn
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34
associated with the remedial action alternatives, permanent
offsite disposal, cannot be implemented until the State of
Colorado provides a facility suitable for the disposal of this
material. This implementation constraint is common to. all of the
remedial action alternatives analyzed in detail, except No
Action.
Effectiveness Analysis:
Alternatives 7, 8, and 10 will meet contaminant-specific
ARARs on those properties where target residual levels for radium
in soils are currently being exceeded. 1 In addition, these three
remedial action alternatives will meet all identified action-
specific and location-specific ARARs and other guidance to be
considered. Alternative 10 is more protective, and thus more
effective, than either Alternative 7 or 8 because contaminated
material, instead of being stored on the property, would be
removed from the property entirely. Alternatives 2 and 9 are
both less effective than either Alternative 7, 8, and 10 because
Alternatives 2 and 9 will meet contaminant-specific ARARs only
after the contaminated material -from each property is removed to
the offsite permanent disposal facility. Alternative 9, is in
turn more protective, and thus more effective, than Alternative 2
because the cap will provide some limited short-term protection
to public health and the environment, whereas Alternative 2, will
. prov~de absolutely no short-term protection to the public health.
and the-environment until the material is removed. No Action
'will not meet the contaminant-specific ARARs on tho~a properties
where target residual levels are currently being exceeded and,
therefore, will provide neither short-term or long-term
protection of public health and the environment. The possible
resulting exposure could result in unacceptable risks to public.
health and the environment.
No Action and, in the interim, Alternative 2 will not reduce
the mobility, toxicity, or volume of the contaminated material on
the properties. Although Alternatives 7, 8, 9, and 10 will not
reduce the toxicity or volume of the radioactive waste, the
contaminated material will be transferred from an uncontrolled
status to a controlled facility or state, thereby reducing
mobility. In addition, an increase in volume is often the result
of the material being disturbed. Thus, Alternatives 7, 8, 9, and
10, since they reduce the chances of the material being
1Target residual levels for radium in site soils have been
established through one of the contaminant-specific ARARs for the
Open Space properties, 40 CFR Part 192. This ARAR is discussed
later in this report and in Section 4 of the FS. It does not
appear that target residual levels are currently being exceeded
at the Brannan property, Ruby Hill Park, and the alley, however,
this premise will be confirmed during Remedial Design of the Open
Space properties. See Table 3-1 in the FS for the radiological
standards comparison for all of the Open Space properties.
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35
di~turbed, also may prevent the volume of contamination from
increasing.
EPA conducted a Public Health Evaluation of Remedial
Alternatives to determine short-term potential for adverse health
effects from human exposure associated with the various remedial
action alternatives. This analysis, summarized in Appendix F of
the Open Space Properties FS, revealed that allot the
alternatives considered except No Action would result in nearly
equivalent exposures during implementation of the remedy. In
addition, all estimated exposures would be well below target
levels established in ARARs. EPA also conducted a Public Health
and Environmental Assessment to determine the long-term potential
for adverse health effects associated with the contaminant levels
present on the Open Space properties. This analysis, summarized
earlier in this summary and contained in Appendix B of the Open
Space Properties FS, showed that there would be a significant
increase in public health risk if the No Action alternative was
implemented at the properties where contaminant-specific ARARs
are currently being exceeded.
The potential for adverse environmental impacts at the Open
Space properties is low. However, leaving the material on the
properties in an uncontrolled state provides an opportunity for
potential environmental impacts during a catastrophic event, such
as a flood or water main break, resulting in a substantial'
dispersal of the contaminants.
Cost Analysis:
The cost analysis for the Open Space properties re~ealed
that there is not a wide variation in costs among the remedial
action alternatives for any given property. However, in general,
for any given property the No Action Alternative is the least
costly remedial action alternative followed by Alternative 2.
For those properties where it is proposed, Alternative 8 is the
most expensive remedial action alternative. For most properties,
Alternative 10 is the next most expensive alternative. In
general, Alternatives 7 and 9 have mid-range and similar costs.
Tables 8-3 through 8-12 in the Open Space Properties FS present a
breakdown of each alternative's cost for each property based. upon
the component measures of cost described above. An even more
detailed breakdown of each alternative's cost is provided in
Appendix G of the Open Space Properties FS. Section 8 of the
Open Space Properties FS contains a sensitivity analysis of these
costs.
In summary, the selected remedy for each property was chosen
from the detailed analysis of alternatives. The analysis was
based upon component measures of implementability, effectiveness,
and cost. Table 3 outlines the detailed analysis 9f remedial
action alternatives summarized above. (See also Section 9 of the
.Open Space Properties Fs.1
-------
I:.!!!!!! !!!!L£!!!!.!!!.--
10'" .0.RI.I.IIII,
r.ff.ellvelle..
Table
3
6181AIIY 0" Al.Tt:llIIATIV£ t:VAUIATlOII
01't:1I 5"AI:£ "11111'1:"'''::;. IIUIVF.I! IIAI,II" SITI
& II u..ah. 1
'10 &etloo
f!" ".""ullce'
'"..""1..
'0 en ""2 eoodilloo. for u.IIo...U'
10 ...11. w....ld ....a b. .U.....d 81
Allle.l. a::;IIII. 10lil'. 1'51:0. C" liD. -.
111111'. ...01 1........
11:111'/11:111' J..ld.ne. .., not a.. ..t
.1 11..111..... 11..1., 11111 I'.... ..."' U..
Aile, If cal'''''''. II... ..cud
" 1,,,,". per d.,. no d.,. I'u ,e.r.
II" &ell08 doc. POt ..d..ce ...,1.1111,.
...rlell,. Rr .01.... D' .h. ...110'
.ell.. ..lerh18. Ilowe.... a...
...11....,... C"..."r.... ... e..r"..lly
C."I""I; I""'. 1:1' liD. ., I..", 11111
I'..~. al.. 'Ih,. ...01 11I4f).
",lIo.,'ah. ....rl.a. ... ..an....I,
I,e........a. 11.,110.. I. noa ,...,
...Iolle ..."' .lve. off ...1.... dau,
I),n.luct. tu I". ...o.,.hl:'.. ".11.
..... eulu"l. .fcc, ,e,..uce..lna.
,.,114.. ,. .ul..cr.. '0 ""I)c...1 vi.
........ .cl.-II ,. lIedun dec.,
,llu.'...:I. can 8cc..-ul.l. In I,UIIIln
1"11111 .ud '11: c.,&:I,,"'.cnl.
<uR.alv. 2
Pc'e..ed lIe~..11
Off.lt. re..."c..t 111.1'0..1
(All 1"ul,er!!..'
"... e...14 o..d.r.o .01.111100.1 4.v.lop-
..oa I.. cN...ol...Ud .re... ('..."h.-
I...aed ..auhh cOII,ld ... dhl'U." or
411ua.0I ...d, a".t a"e, would ,,0 lon..r
".,lde...a'I."lo.
I.e.v.a a.... e.""ot proc..d ....all .. 011-
.Ia. oIl.......a f.cl'la, a. ...aa."I..
&..al...I,aa, re~ulr.d 10, ~AII& loe. C.,.
".c,,", h .....e4 nul '0 I.. ...11.1.1.
...111 111.,2.
11,11« rc_v.1 a. 4"'en.". cOll...ln...a-
.I.eellic 'RAil'. .., oot 1.« ..t. AII&II'.
...11.14 ... .et ..pon .e.....I.
Alte."..h« J
CIn.It. Te.,or.., 1.,,4 Stou..'
011.11. te...nent 111.1'0..1
(A II Ie 4, 1'51"0, 11.......
...4 ".n...n r,ol"'!!!!!-
Te.l'0ury .10.... c.. "..e "c"nlcel
pr
-------
[V!!~~f!!~~!!..-
Alln...llvc 1
11o Act I-
(!tL!~~~!!..)
10181 CoIU 'or Al'l'r0l'r18l.
P.ul'~rt I..
Hut Al'l'licabl.
81'11 . 1" uent worth 8t 8 10 I'.rceol dhcou..1 hClor.
bout - O,.cr81Iun. ~nti tt.h,(~n.lU:c.
Table 3
(cout. )
Alur..811v. 2
De'Qrr.~ 1.80.811
OUllt. ter.lo.1I1 Phpo..1
(All tr~flle.)
D"d"l ucavell"... re...dl.1 .ulon
""I~UU wool~ b. eopul~~ 10 ."1'.011-
."101, IS .re.l,r (wI."I. bu~, !Iu.o
£'1,,1"'001). wI.l.h .. bel.... lb.
III CUi 211 .uII~..d 0' sOO ..e./,r.
0...110 "'Ihu wI.o 81. 1101 ...oclar.4
"lib eI..llup ...M.ld b. upond 10 .....r""'
....1.1, 1 .,..I,r. wI.I," .. 10.1.... lb.
~:II"/ICII' .ul~..nca oi 1l1li .re./,r.
T'"UI...."rt"llo.. oa )sO .11", Iu ..a"lIe
"""0181 ,..,11 II, ""..Id III.olvo drlv.r
c1I,o...re 0' '.4 .re./..... Irl... "Inl..1
CII,uI...8 (O.OOJ ..e.) would occor I..
le..eul ..ublle d...llI. 110.11110111"0...
,,"I... ... .eeldeolll "1'111 ""..ned.
"hl.b ""...~ rl:l..11 h. . .I..or locre...
h. ..po....8I. 'Ph..o..1 '..:1111, .......d
b.. ,.....11.01 "lIh uliulell..OI Ib..
...ur- ....ot.cttve..... 01 bu....n health.
c...tUI ",,8--$160.800
O6J1 1'\1-'$)l1li,)00
AII.rn..11v8 J
00.11. Te.........)' I..o~ 510r.../
011011. l'e,.""ool 018""..1
tAl lI.d, PSCo. 11.......
Iml_!! ~~...!!.!!!.!1--
lII.rlol .Ica..llon, re..dl..l 8"a-
"".hfl ..oold b. ..po,"~ 10 ."I'r..'"
."'.1, U ."./'1 C.I...I. bo~, 0....
['101..1.01), wI.I,.. .. ".1"" II..
10 Ctl 10 .I....~..~ 01 SOO .re./,r.
0.,.1&. wo......., ..hu 8.8 pot l'IDclated
..lIh ,1..11..1' .......01 be "1'0ICd 10
I .re./,r, wI.l.h Ie bel- lb. IICIIP/
ICRl' ...Iddili. 01 100 ..../,1.
If ....,port.tlon ,.po'''.c' w&.tu'4 b.
'dellll.:aI 10 Allerll.lh. 2.
CIl'tUI "".'-$)80,100
06." 1'\I--$I1J ,100
w
.......
-------
£V!~!!:!~~!!!rJ.
1.."I".""uhlllt,
Effecllvene.. .
Allern.llv. ..
o.,~". '''111'''..;..., "'lIdl". SIOU../
01 "II.. ""'."".'11 11101,....1
(AI lI.d, rsc.., n.U8..
a"d .!!!!~!!!!~~!.!!!I
5,,,,11., h: ba.a a"d d..."...u could bee a'"
01'." ...d ~"ltI ...Ie.I..1 I" .h" b"lIdlnl.
III-v".., .h" bollldl"l .ho..ld cUl..aln ..n,
.plll"d ...e.lala.
'..puU" ..ou.. at Ih. fo... p.o"enl..
_Id lot: o."d IInlll olf.II. d"..unl
facllll, la .v.ll..bl.. Av..ll..bIIIIY
.""..I."d b, 5AII& IOI,(If.). f.cllll,..
......"d "ul '0 ... av.II.bl" u".11 1'.1'.11.
511. acc.., .nUlcllon. .lId '"p.ov....
"'Mt.d be: nc~dc.1 10 CUIIZltru..:t tile ..to. lie
..1111 .1 II,. fUll. 1',01'",11.... 5.ou...
f..clll.,... would .e...lcl ....." 01
l"ul,,,,II... fo. S. ,un.
8I;Idl_.22' I..v." In .0118 would b. .ct
"I"'" 11,11 b I I "",,,val.
."",,,v.I .nd '..1""." ..0.... viii not
...d..ee lodd., .nd volu.. of.18dlo.cllv.
v...u. n,. ...1.1111, of .h. ..url.I
..,u... bel d~crc..~d '10.... the 6:onlaln.r
b.u~.. I h...."ver, .h.. u.. 01 blilldl".. fo. '
.'u.I"1I .Ia. cunullI..n .....,Id co"..I" .11'
.1.111"11", nu, ...bllll' of ,.dUlI ... cuuld
I.c .leL.".....I, bll' could .11 II p,.c'CII' a
I'.ubl". vllhl" .h.. cu"I.I"er bulldl"l1
u~~d 'or .tur..c.
Table 3
(cont. )
Allerluiliv. '.I
0011.. 'c.puu" l:o"lal"',,"1 (Ca....I"II)/
Olhll. re...,..."1 IlIo"u..I
(&I I trupu!!!!)
'..pu.er, cOllul".ent un Ia.V. ..chulc81
p.uble.., .uch .. f;ollu.. uf .h. "I'-
'eapon., conl.h-nt .t ..ch p.op.rt,
o;ould b. ....d un.1I ofhU. d..pu..1
f.clll., I. "v.ll..bl... Avallabill.,
re",,".d by SAII& lOlob.). f.cl IllY"
au....d IIU, '0 ... .vall.blc unlll I9U.
511. .cc... .unlcllon. a"d app.oval.
-Id hav", 10 be laplc"'"I.d 10 c""-
,UllCI Ih. u". aL lb. ",.o"erllce. n,.
cOlluln...III hclllty _Id ....ulci
"."lIe uf Ih. .1... lu. S y..,.,
C.pp I na wou I d Dot ....1 100 CFa 19 J .nd
HI 1:111 lO .undord. 10' . pc,...".'"
.e...dy. IIc"",v.I .nd le.I""." unoll.
conul"'''"1 viti 1101 red..c. lodclt, .nd
volll"" of ..dlo.c.Iv. VUI... lh.
8Oblllt, 01 II.. .a18."" vIII b.
d~clca.c" fur .ro.lon.t 8.p.Ct8.
A"e.n.,lv. 10
On.II. "".I'uu., .ulldlnll SIOhll" 81
Card Co...u..tlun 100 U/
01"11.. ......n.," 0.........1
I !!!...!!0l'cr II "! I
5YIIIII.llc b... 0' d...p.un coulol 11...1:
0l'~o .od '1'111 .au.bl 10 Ih. ",.11.11011.
"owner, Ih.. bulloll"l .hunld cUlluln .0'
opllle4.8....I"la.
'~.""U., 8Iora.. _u14 b. u..d uOIII off-
.lle 41.pa..1 ',cllll, I. .v.II.bl..
Aval......II, '~'I..I..d II, SUA lOlolU.
F.c II II~ to ...u.ed oul 10 be anll.bl.
ulI.1I l'l'JJ.
A"p,uv.II fo. u.lnl .h. 011 I P'OPUI' fo.
.~d'u.cllv. ......1.1 .10'.11" n".d .0 b.
ubu"",d.
lladl_-JJ6 I.v.I. ID '0111 woul4 b. ioU
ul,on 11111..1 ....,val.
M"",,,v.I and I..po.a., con..ln..laa.lon
will 1101 ..duc. 10&lcll, .nol vol...e of
..oIlu.CltY. wa.... Die "'''1111, ul .11.
..,<11.1 would b. dec...~.d unl... a
coul.lncr b,-u~ci bowcv~f. Ihe u.. of 8
bulldlllil 10' 610.1"11 .h. cOII..I"~n w....ld
cuouln .0'"1'111111.. The ..,blllty of
,.,hUt ... cuul~ ". ..cere...:", IJ"I COU."
..III p.uen. . p.ubl.. wllbln .be
cUlluln.. bullollnl und fo. a,u'.I1'"
w
00
-------
-_!!!!~~!~...f.!-!!..!!18
[lleCllvc..e.. (cont 1.....01)
.ltelll.llv. .
o...n. T..I'"18''' ...lldlnl St""le/
011.11. rc....."..t PI'p....I
(U "col, '5':0, 11.....
8..d_!!:!!!....n rrol'o,"!!!!)
Pt..rln, ..CI..' '00. ..e_edl.' act'un
VO"C"8 "uu'd b. .'ro8cd 10 .1~Ilro.l-
..'d, IS ..e./,I (..10..1. bud, II....
E'I..lulc.,,), ..hlch .. belllw the 10 Cfa
10 I..Iddl.." 01 SilO ..../,.. O".lu
'HU"~'. "hu a..e puI a..uclau:d "I'"
etc.unp .......... bll ..,.08&:" to .1'11(01'-
..u I, I .'../'1, ..lIIeh .. bel.... 110.
111:11"":11' .....01..01 "I 1110 ..e./,I-
TU"SI'''I'.II".. lloh ..ould lie Idc"tlc.I
10 .I'..lIall.c 1.
1"..1 Co... 10. 'l'p.opl18tc
""I,ClII..
C.I'~" I ",. --$~86,'OII
01>1. 1'11--$201,0110
.1'11 . 1'......1 ..olth ., . 10 I.Cleolll dhcou..' I.c,o...
"out . Opc rat 1o... ...01 1...I..tclI.llc..
Table 3
(coot.)
U,...ath. ,
0...1'. Tc....."" c"..t.I"....' (C.ppllll)/
UI hit. h,..n.llt Oh......1
(UI "!!C~HI..I
U..rl... ..ca..lloa. ....edl.t action
WII...". ..011101 bc ........01 to .1'",0.1.1101,
IS ..e./,. ("',01011..01,0.... [q"lnlent).
wI,ld. Ie b.l"w 'he 10 U' 20 .....d..01 01
SilO ..../,.. lIn.h. wo.hra ,,100 ... "0'
..."eI.t.d ..,,10 cI",,"p "",,,101 II. .'PO""
'0 I .1.."1, ....Ieh .. be low the
\101'/11:111' Iliidelill. 01 100 ..../,. ...01
th. ..0 t:'" "0 ..."d8,d 01 2S ....Ir' .,
th. "o;I"t, ..",.......,. 1"".1'0....101'
e.po."I'" ..0..1.. lie Identlcel 10
"tulI.,h. 2.
C.p~'. 1",,8 - -$SU ,0011
Ot.tl 1'\1--$)10,000
Uu.n.t I.. 10
0...1.. 1..,,,,..., 1,,11.11"1 Stnrel. cI
C..d CoII,....tl.... (01' III
Ollolu 1'...."."1 Ohp..ul
(!!L!!~!!!!!!)
IJu.lnl ..ca.ulon. le.edl.t ~cllon WOf..,.
.."..101 b. "PO"" 10 .1'1',0.1..1.1, .
IS ..../,1 ("',01. bud, Pu.. [q"I..tent),
"blch h ".Iow tbe 10 t:tll 211 1..ldl"... O.
SuO .Ic./yr. U".1'8 vO.".f. "ho af. nut
a.lo&:l,ced "llh cle8nup wou.1I .... ..pu8.4
to "!'P,o.I..tel, , CI..lrl, wI,ld. II ".Iow
lb. III:hr/H:1IP 118"dud ul lOll ."."1.
1""'I'0I18tl"" I".' ......1.. II. Id.nllcal
10 ,"un.th. 2. .
t:.II~ 18 I I'll. - -$JIl, SOlI
Ot.1I hI- -$)U ,600
.W
\0
-------
40
Selected Remedy
This Record of Decision addresses the contamination present
on the Open Space properties. This is the seventh Record of
Decision for the Denver Radium Site. EPA's selected remedy for
each of the Open Space properties is described below.
Allied property:
EPA's preferred ~lternative for the Allied property is
Alternative 6, Offsite Permanent Disposal. This alternative,
however, was eliminated during the initial screening of remedial
action alternatives because, until the State of Colorado provides
a permanent disposal facility for material from the Denver Radium
Site, this alternative cannot be implemented. EPA"has therefore
determined that the appropriate extent of remedy at the Allied
property is Alternative 9, Onsite Temporary Containment
(Capping), Offsite Permanent Disposal. The State of Colorado has
been consulted and concurs with the selected remedy.
Remedial Design for the Allied property will include the
selected remedy, Alternative 9, and EPA's preferred remedial
action alternative, Alternative 6, Offsite Permanent Disposal.
Should the State of Colorado fulfill its obligation to assure the
availability of a suitable disposal facility for material from
the Denver Radium Site by the time EPA has concluded Remedial
Design for the Allied property, EPA may implement its preferred
alternative, Offsite Permanent Disposal.
Brannan property, Ruby Hill Park, and the Alley:
EPA's selected remedy for the Brannan property, Ruby Hill
Park and the alley is Alternative 1, No Action. According to the
RI, it does not appear that the radium contamination in soils on
these properties exceeds the target residual levels established
in contaminant-specific ARARs for the Open Space properties.
Additionally, unless extensive exposure periods occur, the
limited amount of contamination on these properties would not
result in exposures to the public exceeding the NCRP or ICRP
guidelines for gamma radiation.
However, in the case of the alley, EPA makes the following
recommendations:
1. That the City and County of Denver improve existing
institutional controls so that all routine maintenance,
repair, or construction activities in the alley carried out
by government agencies, utility companies, contracting
companies, private individuals, etc., will be monitored; and
2. That the City and County of Denver consider removing or
requir.ing the removal of any contaminated material excavated
during routine maintenance, repair, or construction
activities-in the alley to a facility approved for the
storage or disposal of such contaminated material.
-------
41
EPA believes these recommendations will more successfully be
carried out if the alley is included in the institutional
controls program for Streets, Operable Unit VII of the Denver
Radium Site. The City and County of Denver is developing these
institutional controls under a cooperative agreement with the
State of Colorado.
Data on the Brannan property, Ruby Hill Park, and the alley
will be reviewed during" Remedial Design of the Open Space
properties, and if necessary, additional data will be collected
to confirm that the target residual levels are not being
exceeded. If EPA determines that the costs of additional
sampling for this purpose would exceed the costs of cleanup, or
if the review indicates that target residual levels are exceeded,
a remedial action alternative other than No Action may be
implemented at these properties.
In the case of the Brannan property and the alley, "
Alternative 9, Onsite Temporary Containment (Capping), Offsite
Permanent Disposal, will serve as the backup alternative. If
future data evaluation indicates that target residual levels are
being exceeded at Ruby Hill Park, or ~f the costs of additional
sampling to make a determination exceed the costs of cleanup,
then Alternative 10, Temporary Building Storage at Card
Corporation Property (OU X), Offsite Permanent Disposal, will be
implemented at the Park.
. .
The State of Colorado has been consulted and concurs with
the selected remedies and the backup remedies for the Brannan
property, Ruby Hill Park, and the alley.
CSRR, DWD, PSCO, IHOP and Larry's, and Thomas Realty properties:
The EPA preferred alternative for these properties is "
Alternative 6, Offsite Permanent Disposal. This alternative,
however, was eliminated during the initial screening of remedial
action alternatives because, until the State of Colorado provides
a permanent disposal site for material from the Denver Radium
Site, this alternative cannot be implemented. EPA has therefore
determined that the appropriate extent of remedy for these
properties is Alternative 10, Temporary Building Storage at Card
Corporation Property (OU X), Offsite Permanent Disposal.
Remedial Design for these properties will include the
selected remedy, Alternative 10, and EPA's preferred remedial
action alternative, Alternative 6, Offsite Permanent Disposal.
Should the State of Colorado fulfill its obligation to assure the
availability of a suitable disposal facility for material from
the Denver Radium Site by the time EPA has concluded Remedial
Design for these properties, EPA may implement its preferred
alternative, Offsite Permanent Disposal. The State of Colorado
has been consulted and concurs with the selected remedies for
these properties. "
-------
42
Description of the Selected Remedies:
The selected remedy for the Allied property, and the backup
remedies for the Brannan property and the alley, is Onsite
Temporary Containment (Capping), Offsite Permanent Disposal.
This alternative consists of one temporary management-of-
migration response action followed by one final and per.manent .
source control response action. The temporary management-of-
migration response action at the Allied property consists of
placing a cap over the identified areas of contamination which
cover approximately 4,320 square feet of the Allied property and
account for an estimated 290 cubic yards of contaminated
material. The cap at the Allied property (or the Brannan
property or alley if this alternative is implemented as a backup)
will temporarily limit the spread of the contaminated material by
wind and water erosion and human activity. The cap will also
provide temporary protection of human health by reducing direct
exposure to gamma radiation and by reducing the risk of
inhalation or ingestion of contaminated soil. Placement of the
cap could take one to three months. The cap will be routinely
inspected and restrictions on excavation will be instituted to
maintain the integrity of the cap. The cap will remain in place
until a permanent offsite d~sposal facility becomes available.
. The final and permanent source control response action at
the Allied property (or the Brannan property or the. alley if this
alternative is implemented as a backup) will occur once a
per~anent offsite dispos~l facility becomes availabl~ and
consists of removing the cap and excavating the material which
was temporarily placed under the cap. This material and any
portion of the cap which is contaminated would then be
transport~d by either truck or rail to the permanent offsite
disposal facility. Excavation of the contaminated material under
the cap and transportation of the material to the permanent
offsite disposal facility could take three to six months. A more
detailed implementation schedule for this response action and the
one described above will be developed during Remedial Design.
The selected remedy for the CSRR, DWD, PSCo, IHOP and
Larry's, and Thomas Realty properties is Alternative 10,
Temporary Building Storage at Card Corporation Property (OU X),
Offsite Permanent Disposal. This alternative consists of one
temporary source control response action followed by a final and
permanent source control re~ponse action. The temporary source
control response action consists of removing the estimated 1020
cubic yards of contaminated material from these properties,
placing this material in containers, and transporting the
containers to the Card Corporation property, Operable Unit X of
the Denver Radium Site, for temporary storage until an offsite
permanent disposal facility becomes available. Removal of the
contaminated material from these properties could take one to two
months.
The final and permanent source control response action will
occur once a permanent offsite disposal facility becomes
-------
43
available and consists of transporting the material stored at the
Card Corporation property by either truck or rail to the offsite
permanent disposal facility. The temporary storage facility on
the Card Corporation property would then be decontaminated and,
if necessary, dismantled and the material transported to a solid
waste landfill. A detailed implementation schedule for this
response action and the one described above will be developed
during Remedial Design.
The present-worth cost of the selected remedy for the Allied.
property is $143,600 based upon a ten-percent interest rate, a
five-year discount period, and a perpetual monitoring period.
The cost of this alternative includes placement of the cap over
the contaminated area, and maintenance and monitoring of the
Allied property for a period of five years. This cost also
includes removal and transportation of the capped material and
any portion of the cap which may be contaminated to the offsite
permanent disposal facility when one is available.
The present-worth cost of the selected remedy for the
Brannan property and the alley depend upon whether future data
evaluation indicates that target residual. levels are exceeded
resulting in the backup alternatives being implemented. If
instead of No Action, Onsite Temporary Containment (Capping),
Offsite Permanent Disposal, is implemented at the Brannan
. property, the present-worth cost would be $68,500. If this
remedial action alternative is implemented at the alley, the
present-worth cost would be $41,000. The cost of this
alternative includes costs for the activities itemized above for
the Allied property.
If No Action is implemented at the alley, the State of
Colorado and the City and County of Denver may accept EPA's
recommendation of including the alley as part of the
institutional controls program being designed for Streets,
Operable Unit VII'~f the Denver Radium Site. EPA has already
awarded Superfund Cooperative Agreement funds for this purpose
and consistent with CERCLA Section 104(c)(3), the State of
. Colorado and the City and County of Denver will be responsible
for assuring the payment of all future costs of maintaining and
operating the institutional controls, including proper disposal
of any contaminated material excavated during routine
maintenance, repair, or construction activities in the alley.
The present-worth costs of the selected remedy for Ruby Hill
Park depend upon whether future data evaluation indicates that
target residual levels are exceeded resulting in the backup
alternative being implemented. If instead of No Action,
Temporary Building Storage at Card Corporation Property (OU X),
Offsite Permanent Disposal, is implemented at Ruby Hill Park, the
present-worth cost would be $92,900. This cost includes
excavation of the contaminated material from the Park, placement
of the material into containers, transfer of the containers to
the Card Corporation property, placement of the containers within
the temporary st6rage facility, and maintenance and monitoiing of
-------
'44
the containers and temporary storage facility for a period of
five years. The cost of this alternative also includes removal
and transport of the contaminated material from the storage
facility to the offsite permanent disposal facility,
decontaminating and, if necessary, dismantling the temporary
storage facility at the Card Corporation property, and
transporting the decontaminated material to a solid waste
landfill. The costs are based upon a ten-percent interest rate,
a five-year discount period, and a perpetual monitoring period.
The selected remedy for the CSRR, DWD, PSCo, IHOP and
.Larry's, and Thomas Realty properties is Temporary Building
Storage at Card Corporation Property (OU X), Offsite Permanent
Disposal. The pre~ent-worth cost of the selected remedy for each
of the properties is as follows:
CSRR
DWD
PSCo
IHOP
Larry's
Thomas
$126,800
150,600
94,000
130,700
93,600
147,600
These costs include costs for the activities itemized above
for Ruby Hill Park. The costs are based upon a ten-percent
interest rate, a five~year discount period, and a perpetual
monitoring p~riod.
Operation and maintenance activities will be required to
ensure the effectiveness' of the temporary response actions
associated with the selected remedies. These activities include
site inspections, ongoing radiological monitoring, and possible
minor repairs to the cap on the Allied property or the temporary
storage facility on the Card Corporation property. Also included
as an operation and maintenance activity for cost estimating
purposes i$'a review of the properties which, pursuant to SARA
Section 121(c), must be conducted no less than every five years
if a remedial action is selected that results in any hazardous
substances remaining onsite. Since EPA does not anticipate that
any hazardous substances will remain onsite longer than five
years, the cost of this review is considered a contingency.
Operation and maintenance costs are included with the present-
worth total alternative cost mentioned above.
Statutory Determinations:
Protectiveness: The Public Health and Environmental
Assessment for the Open Space properties summarized earlier in
this document clearly shows that there would be a significant
increase in the risk of contracting lung and other cancer~ if
Alternative 1, No Action, was selected for those Open Space
properties where radium concentrations in soils exceed the target
residual. levels, and the properties were eve~ developed in a way
which might reasonably be expected. The only effective way to
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45
reduce this risk on those Open Space properties where target
residual levels are exceeded is excavation to achieve target
residual levels and removal of the contaminated material from the
properties to an offsite permanent disposal facility. Further,
because the offsite permanent disposal facility would be designed
to isolate the contaminated material from man and the environment
for a thousand years, the se~ected remedy for these particular
properties would provide long-term protection of public health
and the environment. The temporary measures envisioned in the
selected remedy will provide the necessary short-term protection
of public health and the environment.
In addition to preparing the Public Health and Environmental
Assessment mentioned above, EPA conducted a Public Health
Evaluation of Remedial Alternatives, summarized in Appendix F of
the Open Space Properties FS. For this evaluation, exposures to
gamma radiation, inhalation of contaminated soils, and inhalation
of radon decay products were estimated for persons who might be
exposed to hazards during implementation of each alternative
undergoing detailed analysis. These persons include onsite
remedial action. workers, individuals not associated with remedial
activities but working in an onsite office, residents of a home
located outside of the property boundary, a transportation
worker, and an onlooker present during truck transportation of
the contaminated materials. Exposures were calculated for each
remedial action alternative undergoing detailed. analysis other
than No Action. The evaluation revealed that none of the
estimated exposures for any scenario of any remedial action
alternative, including the selected remedies, exceeded exposure
limits set by the relevant and appropriate standard or guideline.
Also, for any given scenario, there was no appreciable difference
among the estimated exposures for the remedial action
alternatives. The risks associated with this type of remedial
action work lie not with poss~ble radiological exposure, but with
the inherent dangers associated with general construction work.
Based upon statistics from the construction industry, EPA
estimates that the number of non-fatal injuries to cleanup
workers would range from 0.013 to 0.056 for the type of work to
be conducted during remedial action at the Open Space properties
and the number of fatalities would range from 0.001 to 0.006.
(See report entitled Open Space Properties, Public Health and
Environmental Assessment, Dose Commitments.) These numbers can
be significantly reduced by hiring competent and properly trained
construction contractors and by strict adherence to the site
safety plan.
The OSWER Directive No. 9355.0-19 states, "Remedies must be-
protective of human health and the environment. This means that
the remedy meets or exceeds ARARs..." EPA has determined that
the selected remedies for each property will meet all ARARs
identified for the Open Space properties. For this reason and
from the analyses conducted in the Public Health and
Environmental Assessment and-the Public Health Evaluation of
Remedial Alternatives and because of the permanence associated
with the design of the offsite disposal facility, EPA has
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46
concluded that the selected remedies for each property would be
protective of public health and the environment once the
permanent offsite disposal component of the selected remedies has
been implemented.
Consistency With Other Laws: Pursuant to SARA Section
121(d), remedial ac~ions shall attain a degree of cleanup of
hazardous substances, pollutants, and contaminants released into
the environment and control of further release which at a minimum
assures protection of human health and the environment. In
addition, remedial actions shall, upon their completion, reach a
level or standard of control for such hazardous substances,
pollutants, or contaminants which at least attains legally
applicable or relevant and appropriate Federal standards,
requirements, criteria, or limitations, or any promulgated
standards, requirements, criteria, or limitations under a State
environmental or facility siting law that is more stringent than
any Federal standard (ARARs).
On November 20, 1986, EPA requested that the State of
Colorado identify potentially applicable or relevant and
appropriate State public health and environmental requirements
for the Card Corporation property (OU X). The State responded to
this request on January 21, 1987, with a list of Colorado
requirements which pertained to the entire Denver Radium Site.
EPA classified all Federal and State public health and
environmental requirements applicable or relevant and appropriate
to the Open Space properties into three categories: contaminant-
specific ARARs, action-specific ARARs, and location-specific
ARARs. A description of each of these categories is provided in
both Section 4 and Appendix.C of the Open Space Properties FS.
Other Federal and State criteria, advisories, and guidance were
also considered. Tables C-1 through C-4 in Appendix C of the
Open Space Properties FS contain a brief description of each
potential Federal and State requirement identified and EPA's
analysis of each requirement's applicability or relevance and
appropriateness to the Open Space properties. EPA has determined
that each selected remedy will meet all applicable or relevant
and appropriate public health and environmental requirements of
Federal and State laws and, therefore, no SARA Section 121(d)(4)
waivers need be invoked. A brief discussion of ARARs for the
Open Space properties is provided below.
The EPA Standards for remedial action at Inactive Uranium
Processing Sites, 40 CFR Part 192, are one of two contaminant-
specific ARARs identified for the Open Space properties~ For
properties contaminated with uranium processing residues, these
standards establish limits for the gamma radiation level and
annual average radon decay product concentration in any occupied
or habitable building and for the radium concentration in soil on
open lands. Although not necessarily applicable to the Open
Space properties since the standards apply only to certain
specifically designated sites where uranium was processed, the
standards are relevant and appropriate to the Open Space
. .
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47
properties because (1) it is the radium content of the uranium
mill tailings which is regulated; (2) the waste products
resulting from uranium ore processing are very similar to those
from both radium and vanadium ore processing; (3) the residues
from both processes enter the environment through the same
exposure pathways; and (4) the adverse health concerns resulting
from exposure to the residues from both processes are the same.
The portion of the standards relevant and appropriate to the
contaminated soil on the Open Space properties and the portion
which serves as EPA's target residual level for cleanup is 40 CFR
Section 192.12 which states:
"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 )
( 2 )
5 pCi/g, averaged over the first 15 centimeters of
soil below the surface, and
15 pCi/g, averaged over 15 centimeter-thick layers
of soil more than 15 centimeters below the
surface."
(40 CFR Section 192.12)
The second contaminant-specific ARAR identified for the Open
Space properties is the Nuclear Regulatory Commission Standards
for Protection Against Radiation, 10 CFR Part 20. These
regulations establish standards for protection against radiation
hazards arising out of activities under licenses issued by the
Nuclear Regulatory Commission (NRC). Because these standards
apply to licensed NRC facilities, they are not applicable to the
Open Space properties. However, EPA has determined that portions
of the regulations are relevant and appropriate to individuals
who would be conducting the remedial action on the Open Space
property. In addition, these regulations are incorporated by
reference in the Occupational Safety and Health Administration
Standards, 29 CFR Parts 1910 and 1926, which, due to the mandate
contained in SARA Section 126, now apply to employees involved in
responses covered by CERCLA. .
Of particular importance is Appendix B of 10 CFR Part 20
which provides limits for airborne concentrations of natural
uranium, thorium-230, and radium-226. Gamma radiation dose
standards for individuals in restricted and unrestricted areas
are cited in 10 CFR Sections 20.101 and 20.105, respectively.
These 10 CFR Part 20 standards alo~g with the 40 CFR Part 192
standards are summarized in Table 4.
EPA has identified one, potential location-specific ARAR for
the Open Space properties, the Executive Order on Flood Plain
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Regll1utory Agency
!rpe of ('.ontailinant
FEUEIlAI.
U.S. EPA-"O CFlt 192.
Suhpart II-SUndards
Ra11i1lDl-226
Concentration
Gamma Radl.tlon.
Radon Dec.y Product
Concenlrut Ion
Nuc1 ear Regu 1atory
COJIIlllhslon (NIU:)
10 c~'n 20
Uranium-natural
AI rhorne Concentra-
llona
Thor I 1118- 2 30
Alrhorne Concentra-
tlonll
Radlum-226 Airborne
Concent ra tI ons
GamD.a radlatlona
Table It
POTENTIAl. CON'I'AHINAN'r-SI'ECTFIC ARAR'S
OI'':N SI'ACE l'nm'F.II'I'IES. IlBiVt:R RAIHU~I SITE
Sundard. Requirement.
Criteria. or 1,IUlItotion
('.omment.
5 pCI/g ahove background
within 15 em of the sur-
face ~eosured over a
100-. area
Standards for cleanup of solla. concentration of
radl,~-226 In land. sveraged over aoy area of 100 aquare
lIeters. Point of ~oDlpllunce Is at 8ny conts.lnuted area
greater than 100.. lIowever. during clcunup al1
contuUllnated areas wOllld be remedlated.
15 pCI/g above background
with In suhse(luent 15 CII
layer! measured over a
100-111 area
20 IIR/hr above hackground
0.02 WI. annual average
0.03 WI. Ilaxlmu..
3
5 pCt/1i . 3Unrestrlcted
100 pCI/m . Rcutrlcted
Re levant, snd appropriate to Indoor gamma radlat 100.
of cOOlI,lhncu h Intilde any site building.
Relevant and appropriate to Indoor radon. Point of com-
pliance is Inalde any site building.
b .
area Point of compltance fa any locstlon within site.
c
srea
~
CD
Point
3 b
] pCI/m ~ Unrestricted are! Point of compltance Is any location within alte.
30 pCI/~ . Restricted area
3 b
3 pCI /m ~ Unrestricted are~ Point of coml,ltance h any locstlon within site.
30 pCI/UI. "cutrlcted srea
5 rem/yr. (5.000 mrem/yr)
c
Restl'lcted area b
500 mreUi/yr. Unrest rl cted
area
Point of compltance h any location within site. site
would be unreatrlcted for reDlCdlotlon workeru.
a"elevllnt anll approl1rlate stalulurd hut' not as protective as 'Other ('.lIldance. see Table It-].
bAn unrctitrlcted urea au recanh~11 88 any place orollnll a waste consolldutton/storoge arca faclltty where access 10 not controllell.
cA rCt.;trlcted urea 19 rcgarded 1.111 any place around a wuste con6011
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49
Management, 40 CFR Section 6.302(b), which requires Federal
agencies.to evaluate the potential effects of actions they may
take in a flood plain to avoid, to the maximum extent possible,
the adverse impacts associated with the direct and indirect
development of a flood plain. Remediation of the contamination
on certain Open Space properties which lie in a flood plain, the
Allied and DWD properties, is not likely to have an adverse
. affect in the event of a flood especially since having the
contaminated material in a controlled state will reduce the
chance that contaminated material would be spread dur~ng a flood.
'As mentioned previously, although the Brannan property lies
within a flood plain, it does not appear that target residual
levels are currently being exceeded and, therefore, No Action is
the selected remedy for this property. Currently, there are no
identified State location-specific ARARs for the Open Space
properties.
Action-specific ARARs are technology-based restrictions
triggered by specific types of remedial measures under
consideration. Once the remedial action alternatives were
developed in the Open Space Properties FS, EPA identified
specific action elements which were part of at least one or more
of the alternatives. These action elements are listed in
Section 6 of the Open Space Properties FS. EPA then identified
numerous action-specific ARARs for each of the action elements.
These action~specific ARARs were evaluated in Appendix C of the
Open Space Properties FS and are presented in Table 6-2 of the
Open Space Properties FS.
In addition to the ARARs mentioned above, EPA also
considered other Federal and State criteria, advisories, and
guidance in determining the appropriate degree of cleanup for the
Operi Space properties. In particular, EPA considered the
National Council on Radiation Protection and Measurements (NCRP)
and the International Commission on Radiological Protection
(ICRP) recommendation for maximum gamma radiation dose to'the ,
whole body. This dose, 100 mrem/yr, is for chronic exposure to
the general public, excluding natural background and medical
radiation. This recommended level is more protective than the
level established by the NRC in its regulations (10 CFR Part 20),
and will be used in evaluating exposures to those working on the
site but who are not associated with remedial cleanup of the Open
Space properties.
SARA Section 121(d)(3) codifies EPA's offsite disposal
policy, which requires that offsite disposal of any hazardous
substances, pollutants, or contaminants from a Superfund site
take place only at a facility that is in compliance with
applicable Federal law and all applicable State public health and
environmental, requirements. Furthermore, the unit to which these
wastes are transported must not be releasing any hazardous waste
or constituent to ground water, surface water, or soil, and any
such releases from other units at the facility must be controlled
by an approved corrective action program. It is incumbent upon
the State of Colorado, as part of its CERCLA requirements, to
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50
assure the availability of a disposal facility which is in
compliance with EPA's offsite disposal policy.
Cost-effectiveness and Utilization of Permanent Solutions
and Alternative Treatment Technologies or Resource Recovery
Technologies to the Maximum Extent Practicable: Alternative 10,
Temporary Building Storage at Card Corporation Property (OU X),
Offsite Permanent Disposal, is a cost-effective. remedial action
alternative for the CSRR, DWD, PSCo, IHOP and Larry's, and Thomas
Realty properties. This alternative effectively mitigates and
minimizes threats to and provides adequate protection of public
health and the environment. This remedial action alternative
will result in the removal of contaminants from these properties
to achieve target residual levels and will eliminate the need for
long-term management at these properties, freeing these
properties for unrestricted use. These results cannot be
achieved by the methods envisioned in any of the other remedial
action alternatives considered for these properties.
The selected remedy for the Brannan property, Ruby Hill
Park, and the alley is No Action. Since it does not appear that
the target residual levels of radium in soils are being exceeded
at any of these properties, remedial action is not necessary, and
therefore, No Action is cost-effective. - .
Alternative 9, Onsite Temporary Containment (Capping),
Offsite Permanent Disposal, is a cost-effective remedial action
alternative for the Allied property. This alternative
effectively mitigates and minimizes threats to and provides
adequate protection of public health and the environment.
Although the temporary building- or land-storage facilities
envisioned in Alternatives 7, 8, and 10 may be slightly more
protective than the cap conceived of in Alternative 9, EPA
believes the temporary cap will provide the necessary short-term
protection for the Allied property especially in light of the low
level of activity on the property and the access controls which
already exist on the property.
The selected remedies will address the principal threat at
the Open Space properties. However, the selected remedies do not
satisfy the statutory preference for treatment as a principal
element. As part of the selection of remedy process~ EPA
evaluated permanent solution. to the hazards associated with the
specific substances present on the Open Space properties.
However, since the hazardous substance associated with the Open
Space properties is a radioactive element, the number of
treatment technologies which may successfully reduce the
mobility, toxicity, and volume of the hazardous substance is
extremely limited. The characteristic of spontaneously emitting
energy and subatomic particles is a property inherent to each
atom of a radioactive element and which cannot be altered or
destroyed by any chemical or physical treatment known today.
Most treatment and resource recovery technologies concentrate the
radioactive e~ements present in the waste, increasing toxicity
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51
without sufficiently reducing volume or mobility. These.
treatment and resource recovery technologies will leave a waste
product which is still radioactive. Nonetheless, EPA considered
several treatment and resource recovery technologies in the
technology scoping and screening phase and even the initial
alternative screening stage of the Open Space Properties FS.
However, no technology was found which would result in a
permanent and significant decrease in the toxicity, mobility, and
volume of the hazardous substance, radium, which is present on
the Open Space properties.
Future Actions
The future remedial activities that are required to complete
remedial action at the Open Space properties are:
( 1 )
( 2 )
( 3 )
( 4 )
( 5 )
Design remedial actions including confirmatory sampling
needed to verify whether "No Action" is an appropriate
response at the Brannan property, Ruby Hill Park, and the
alley. .
Enter into State Superfund Contract with State of Colorado.
Conduct temporary remedial actions for contamination present
.on Open Space properties.
Select and, if necessary, design and construct permanent
disposal facility. (This activity is to be conducted by
State of Colorado.)
Remove contaminated material from the Allied property and
the temporary storage facility on the Card Corporation
property and transport to permanent disposal facility.
(~) . Confirm that the Open Space prop~rties have been
decontaminated to conform with the requirements of ARARs and
can be made available for unrestricted use.
Schedule
Dates for completing key milestones leading to remedial
action at the Open Space properties are highlighted below:
( 1 )
( 2 )
( 3 )
Complete design of remedial actions by September 30, 1988.
Finalize State Superfund Contract with State of Colorado by
September 30, 1988.
Initiate remedial actions no later than during first quarter
fiscal year 1989.
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