PB98-964409
                              EPA 541-R98-177
                              March 1999
EPA Supei fund
      Record of Decision:
      Portland Cement
      (Kiln Dust #2 & 3)
      Salt Lake City, UT
      8/17/1998

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     PORTLAND CEMENT SUPERFUND SITE
          (KILN DUST #2 AND #3)
          SALT LAKE CITY, UTAH
            RECORD OF DECISION
     OPERABLE UNIT THREE - GROUND WATER
UNTTED STATES ENVIRONMENTAL PROTECTION AGENCY
                REGION vm

              AUGUST 17, 1998

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                               RECORD OF DECISION
                                   DECLARATION

Statutory preference for treatment as a principal element is not met and five-year review is
required.

SITE NAME AND LOCATION

Portland Cement Site (Kiln Dust # 2 & 3)
Salt Lake City, UT

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected remedial action for Operable Unit 3 of the Portland
Cement Site in Salt Lake City, Utah (the "Site").  The remedy was chosen in accordance with
CERCLA, as amended by SARA, and the National Contingency Plan. This decision is based on
the administrative record file for the Site.

The Utah Department of Environmental Quality (UDEQ) has jointly worked with the United
States Environmental Protection Agency (EPA) to select a remedy for OU3.

ASSESSMENT op THE SITE

Actual or threatened releases of hazardous substances from the Site, if not addressed by
implementing the response action selected in this record of decision, may present an imminent
and substantial endangerment to public health, welfare, or the environment.

DESCRIPTION OF THE REMEDY

This operable unit is the final action of three operable units for the Site. The first two operable
units addressed cement kiln dust (CKD) and chromium-bearing refractory bricks which were
landfilled at the Site. The remedy for these operable units involved excavation and disposal of
over 500.000 cubic yards of CKD, bricks, and contaminated soil.  This operable unit deals with
residual heavy metal groundwater contamination which occurred as a direct result of the CKD.
The groundwater contamination is the only threat remaining at the Site. The selected remedy is
Monitored Natural Attenuation, which relies on existing conditions and natural processes  to
contain the contamination within Site boundaries and gradually reduce contaminant
concentrations in the groundwater. It is expected that over 100 years will be required to achieve
clean-up goals; EPA considers this .time frame reasonable given the particular circumstances of
the Site.

    The major components of the selected remedy include:

    • Long-term ground and surface water monitoring to ensure the efficacy of the remedy
    and protection of human health and the environment.

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    •  Formal institutional controls in the form of groundwater use restrictions to prevent
    human exposure.

STATUTORY DETFRMINATIONS

The selected remedy is protective of human health and the environment, complies with Federal
and State requirements that are legally applicable or relavent and appropriate to the remedial
action, and is cost-effective. This remedy utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable. However, because treatment of the principal
threat at the Site was not found to be the most appropriate alternative, this remedy does not
satisfy the statutory preference for remedies that employ treatment that reduces toxicity, mobility,
or volume as a principal element.

Because this remedy will result in contaminated ground water remaining on-site above health-
based levels, a review will be conducted within five years after commencement of remedial
action to ensure that the remedy continues to provide adequate protection of human health and
the environment.

EPA has determined  that its future response at this site does not require physical
construction. Therefore, the site now qualifies for inclusion on the construction completion
list
Max Dodson                                             Date
Assistant Regional Administrator
U.S. Environmental Protection Agency
Region VIII
"The UDEQ has worked in partnership with EPA throughout the RI/FS and concurs with the
selected remedy, although it does so on the basis that it is technically impracticable to achieve
MCLs in a reasonable time frame."
       R. Nielson
Executive Director
Utah Department of Environmental Quality

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                                     Table of Contents
Section
1
2
3
4

5
6
7
8

9

10
11
Appendix A

Appendix B
Title
Site Location and Description
Site History and Enforcement Activities
Highlights of Community Participation
Scope and Role of Operable Unit
within Site Strategy
Summary of Site (OU3) Characteristics
Summary of Site (OU3) Risks
Remedial Alternatives
Summary of the Comparison of
Alternatives
Monitored Natural Attenuation -
The Selected Remedy
Statutory Determinations
Explanation of Significant Changes
Detailed Analysis of ARARS
i
Responsiveness Summary
Page
1
4
6

7
8
13
22

44

49
51
54
A-l

B-l
Record of Decision
Portland Cement Supcrfiiad Site
Operable Unit Three
Table of Contents

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                                     List of Figures
Figure Number

1-1

1-2

5-1

5-2


5-3


6-1


7-1



7-2



7-3



7-4



7-5
Description

Site Vicinity Map

Site Map

Geologic Cross Section

Potentiometric Surface Map
of Shallow Aquifer

Potentionmetric Head Difference Map
Shallow and Intermediate Aquifers

Distribution of Arsenic in the Shallow
Aquifer

Predicted Arsenic Distribution in the
Shallow Aquifer After 50 Years
Natural Attenuation

Predicted Arsenic Distribution in the
Shallow Aquifer After 100 Years
Natural Attenuation
Predicted Arsenic Distribution in the
Shallow Aquifer After 50 Years
Pumping Option A
 Predicted Arsenic Distribution in the
 Shallow Aquifer After 100 Years
 Pumping Option A
Page

2

3

9

10


11


14
 Predicted Arsenic Distribution in the
 Shallow Aquifer After 50 Years
 Pumping Option B
30
31
34
35
                                                                           36
 Record of Decision
 Portland Cement Snpcrfund Site
 Operable Unit Three
                                               Ttble of Contents

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Figure Number             Description                                     Page

7-6                        Predicted Arsenic Distribution in the
                           Shallow Aquifer After 100 Years
                           Pumping Option B                               37

7-7                        Predicted Arsenic Distribution in the
                           Shallow Aquifer After 50 Years
                           Pumping Option C                               38

7-8                        Predicted Arsenic Distribution in the
                           Shallow Aquifer After 100 Years
                           Pumping Option C                               39
 Record of Decision                                                           Table of Contents
 Portland Cement Superfwd Site
 Operable Unit Three

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                                   List of Tables
Table Number

6-1

6-2

6-3

6-4

6-5

6-6

7-1


8-1

8-2
Description

Hazard Quotients for COCs

Federal MCLs for COCs

Health-Based Goals for a Resident

Local Background Quality

Cleanup Goals for COCs at OU3

ACLs for Discharges to the City Drain

Remedial Technologies Evaluated by EPA and
UDEQ

Comparative Analysis of Alternatives

Summary of Remedial Alternative Costs
16

18

19

19

20

21

24


47

48
Record of Decision
Portland Cement Supcrfoad Site
Operable Unit Three
                                              Table ofCoateats

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LO SITE LOCATION AND DESCRIPTION

The Portland Cement Superfund  Site (Site ID # 0800690) is located in Salt Lake City, Utah
(Figure 1-1).  The Site is bounded by Redwood Road to the east, Interstate 215 to the west, the
Jordan River overflow  canal (Surplus Canal) to the south, and Indiana Avenue to the north
(Figure 1-2).  It comprises approximately 71 acres and is divided into three smaller areas known
as Site Two,  Site Three, and the West Site (Sites One, Four, and Five are located in different
areas and are not NPL sites). The topography of the area is relatively flat.

The area surrounding  the Site is primarily industrial and borders low-density residential  and
vacant or agricultural land.  The land use to the north, west,  and south is commercial and light
industrial.  Residential areas exist east of the Site and include single-family dwellings, mobile
home parks, and some high-density multi-family residential units. There are currently no buildings
on the Site.   A high  capacity underground sanitary sewer pipe with above ground manholes
traverses the  Site from north to south.  A  chain-link fence was constructed around the Site in
1989 to prevent unauthorized entry.

The risks posed by the Site derive from  cement kiln dust (CKD) and chromium bearing bricks
which were landfilled within the Site boundaries.  CKD contains several heavy metals including
arsenic, cadmium, chromium, lead, manganese, and molybdenum.  These metals are present in
both surface soils and ground water at the Site at concentrations potentially harmful to human
health.  Additional characterization  information is included  in Sections Five  and  Six  of this
document entitled "Summary of Site Characteristics" and "Summary of Site Risks."

The surface soil contamination was addressed beginning in 1992. The remedy, which consisted
primarily of the removal and disposal of  over  500,  000 cubic yards of CKD and contaminated
soil,  was implemented  by the  Utah Department  of Environmental Quality (UDEQ) and was
completed in December 1997.  This decision document is directed at resolving the ground water
contamination problem at the Portland Cement Site, referred to as Operable Unit Three  (OU3).
This is a final record of decision (ROD) and there were no interim RODs. This operable unit is a
combined EPA/State lead.
Record ofDeciaoa                                      .                         PtgcNo. 1
Part/and Cement Supcrfimd Site
Operable Unit Three

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                          Suite 550
                 A Lokewood. CO 80228
         «soavweui.UKTs     (303) 980-6800
PORTLAND CEMENT SUPCRFUND SITE

   SITE VICINITY MAP

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            EXPLANATION


           CKD Boundaries
—-	   Fence  Lines

[        |  Site Areas
                  V


                 I
    4001   200'
                              400-
            SOU: I'  .  
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2.1 SITE HISTORY

Between 1965 and 1983, CKD and chromium-bearing refractory bricks were deposited on the
Site resulting in soil, surface water, and ground water contamination.  All waste CKD was the
result of operations at the Portland Cement plant located at 619 West 700 South in Salt Lake
City, Utah.  The plant was owned and operated by Portland Cement Company of Utah (PCU)
until September 1979, when Lone Star Industries (LSI) purchased the stock of PCU.  The name
of the company was then changed to Utah Portland Quarries, Inc. Although the waste CKD was
placed on the Site by PCU and LSI, neither company owns the land comprising the Site.

In response to complaints from area residents who were concerned about windblown waste CKD,
the EPA initiated a Preliminary Assessment, which indicated a potential for human health risk to
the nearby community. In April 1984, LSI voluntarily began environmental investigations at the
She  that included installing  ground  water monitoring  wells  to determine if ground water
contamination was present.

Sites  Two  and Three (but not the West Site) were proposed for inclusion on the National
Priorities List (NPL) in September 1984. In 1985, the investigation was organized and expanded
as a Remedial Investigation/Feasibility Study (RI/FS) under a Consent Decree issued by the State
of Utah. The entire Site (including the West Site) was formally placed on the NPL on June 10,
1986. For construction management purposes, the Site was originally divided into two operable
units:

   • OU1, which was defined as the "pure" CKD deposited on the Site, and
   • OU2, which was defined as the chromium-bearing bricks and contaminated on-site soils.

LSI completed a Phase I and Phase n Remedial Investigation Report for OU1 and OU2 in 1989
(Dames & Moore, 198 9a)

EPA issued a ROD for OU1 in July 1990.  The selected remedy consisted of excavation and off-
site disposal of the the CKD, as well as  separation and temporary on-site storage of the
chromium-bearing bricks and ground water monitoring.  In March 1992,  the OU2 ROD was
issued.  The OU2 remedy called for excavation of contaminated soil (defined as soil containing
concentrations of lead greater than 500 milligrams per kilogram of soil [mg/kg] or concentrations
of arsenic greater than 70 mg/kg), treatment of contaminated soil and chromium bearing bricks to
enable land disposal,  and off-site disposal.   A 18 inch protective layer of clean fill was to be
installed on the Site.  The  OU2 ROD also called for ground water monitoring to evaluate the
nature and  extent of ground water contamination at the Site.  In May 1992,  OU1 and OU2 were
merged into a  single operable unit through a ROD amendment for the purpose of implementing
Record of Decision                                                              Page No. 4
Portland Cement Superfuad Site
Operable Unit Three

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the selected remedies for both OUs concurrently.    Among other things, this amendment also
eliminated  the soil  treatment requirement of the original  OU2 ROD.  The remedies were
completed in December 1997, resulting in the removal of nearly all CKD, contaminated soil, and
chromium bearing bricks from the Site.

More recently, a third (and final) operable unit was defined (OU3) consisting of contaminated
ground water beneath the Site. A Streamlined Human Health Risk Evaluation (SRE) prepared in
December  1995 concluded that the ground water contamination poses an unacceptable risk to
humans exposed to Site ground water. These risks are discussed further in Section Six (Summary
of Site Risks) of this document.

23 ENFORCEMENT ACTIVITIES

EPA sent a Special Notice Letter to the Potentially Responsible Parties (PRPs) on September 17,
1990 advising them of their potential liability. The PRPs at this Site are:

Lone Star Industries,
Williamsen Investment Co.,
Lawrence D. Williamsen,
Sidney M. & Veoma H Herman,
Herman Family Trust, and
Southwest Investment, Inc.

With the exception of Lone Star Industries, all PRPs are past or present property owners.

Under a  Consent Decree negotiated with the State of Utah in 1985, LSI performed the RI/FS.
LSI filed for bankruptcy in 1990, and as part of the settlement of the claim, a total of 18.5 million
dollars in securities was paid to the EPA, US Department of Interior, and the State of Utah. With
this action, the liability of LSI was fully resolved.

As of this writing, only negotiations with the Williamsen's are ongoing. All other parties have
resolved  their liabilities at the Site.
Record of Decision                                                               Page No. 5
Portland Cement Superfuod Site
Operable Unit Three

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3.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION

Throughout the entire Portland Cement OU1 and OU2 remediation, the public was extensively
involved. Detailed discussion of public participation activities for OU1 and OU2 can be found in
the Record of Decision for those units.  At this late stage, little public interest remains concerning
this operable unit.  However,  concern over the ground water contamination during the OU1 and
OU2 actions was high.  These concerns were largely alleviated once the ground water problem
was properly characterized and source materials were removed.

The Proposed Plan for OU3 was released by UDEQ for public comment on January 20, 1998.
Prior to preparation of this ROD, a public meeting (January 21,  1998) and comment period
(January 20 - February 21,  1998) were conducted which addressed  the Proposed Plan.  Notices
were published in the Salt Lake City Tribune and the Deseret News.  Only one  attendee was
present at the public meeting and indicated agreement with the plan. More information on these
recent community involvement efforts is found in the Responsiveness Summary of this document
(Appendix B).

Information repositories for the Site are located at the Utah Division of Environmental Response
and Remediation in Salt Lake City and the EPA Superfund Records Center in Denver, CO.

This decision document presents the selected remedial action for OU3, chosen in accordance with
CERCLA, as amended by SARA, and  the National Contingency Plan (NCP).  The decision for
this operable unit was based on the administrative record.
Record of Decision                                                             Page No. 6
Portland Cement Supcrfimd Site
Operable Unit Three

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4.0 SCOPE AND ROLE OF OPERABLE UNIT WITHIN SITE STRATEGY

Operable Unit Three is the final operable unit and response action for the Portland Cement Site
and deals exclusively with residual ground water contamination.  All other response actions are
complete.  As discussed in subsequent sections, ground water contamination is contained within
Site boundaries and in the shallowest aquifer.  The source of the ground water contamination,
(overlying CKD and contaminated soil) was removed during remedial actions for OU1 and OU2.
The area was regraded nearly level with clean backfill and seeded.  This source removal was
effectively the first stage of ground water remediation.
Record of Decision                                                             Page No. 7
Portland Cement Superfuad Site
Operable Unit Three

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5.0 SUMMARY OF SITE (OU3) CHARACTERISTICS

The Site is located in the Salt Lake Valley, Utah.   The Salt Lake Valley is bounded on the west
by the Oquirrh Mountains and on the east by the Wasatch Range.

There is one major and several minor aquifers in the Salt Lake Valley.  The deep aquifer, referred
to as  the Principal Aquifer, is confined throughout most of the Valley and serves as the primary
source of ground water for wells in the Salt Lake City area.  Over portions of the Valley, a clay
layer as thick as 360 feet separates the Principal Aquifer from overlying aquifers.

The aquifers investigated at the Site are referred to as the shallow aquifer and the intermediate
aquifer. Both are located above the Principal Aquifer.  The shallow aquifer is unconfined, while
the intermediate aquifer is confined between two laterally continuous clay layers.  The upper clay
layer  separates the shallow and intermediate aquifers and is approximately ten feet thick.  The
lower clay layer separates the  intermediate  aquifer from  underlying aquifers  (including  the
Principal Aquifer) and is of unknown thickness.

Geologically, the shallow aquifer is comprised of silt and fine-grained sand from the water table
down to the upper clay layer at approximately 25 to 30 feet below ground surface.  Hydraulic
conductivity in the shallow zone varies from one foot/day  in Site Three to approximately 50
feet/day near the Surplus  Canal.  Depth to water varies seasonally and across the Site, but is
generally less than ten feet. Total dissolved solids (TDS) concentration in the shallow aquifer is
generally greater than 30, 000 milligrams/liter (mg/L).

The intermediate zone occurs below the upper clay layer as a continuous layer of poorly sorted,
silty,  fine-grained sand to well sorted medium-grained sand.   The intermediate aquifer is typically
five to twelve feet thick, at depths of 40 to 55 feet below ground  surface.  Figure 5-1 shows a
geologic cross section through the Site with the two aquifers noted.  The location of the cross
section in Figure  5-1 is shown on the map in Figure 5-3.  Ground water flow in the intermediate
aquifer is generally to the northwest.
                                  i
Any flow occurring between the intermediate and shallow aquifers appears to be upward from the
intermediate  aquifer  into  the  shallow aquifer.   This  can be  shown  by  the difference in
potentiometric head for adjacent wells- screened in each unit. Figure 5-3 is a map showing the
difference in head between the intermediate and shallow aquifers during  August 1994 and July
1995. As shown in the figure, there was an upward vertical gradient between the two aquifers
everywhere beneath the Site during the August 1994  and July 1995 monitoring events. A review
of available historical water level data reveals that this trend is persistent throughout the year.
Thus, any movement  of ground water between the two aquifers is upward from the intermediate
aquifer to the shallow aquifer. This is important with  respect to the migration of contamination as
Record of Decision                                                                 Page No. 8
Portland Cement Supcrfimd Site
Operable  Unit Three

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it precludes downward migration of shallow contaminants.  To date, sampling of the intermediate
aquifer has revealed no contamination.

Ground water flow in the shallow (contaminated) aquifer is complex due to interaction with local
surface water and underground utility pathways.  Figure 5-2 is a potentiometric surface map for
ground water in the shallow aquifer.  Primary areas of recharge are the unlined Surplus Canal
along the southern boundary of the Site and underflow along the eastern Site boundary. Minor
contributions from infiltrating precipitation occur as well, though this contribution is minimal
because the Salt Lake Valley is relatively arid. All shallow ground water eventually discharges to
the City Drain, an unlined storm water ditch that bisects the Site and flows east to west.  Some
discharge is direct underflow, while some occurs as discharge to the sanitary sewer and an unlined
storm water ditch on the western portion of the Site, both of which empty directly into the City
Drain.

The sanitary sewer is buried at an average depth of 17 feet below grade and bisects the Site from
south to north. From approximately 150 feet south to 500 feet north of the City Drain, the
bedding material of the sewer line appears to be removing ground water from the shallow aquifer
and routing it to the City Drain (Figure 5-2). The effect of the sewer line bedding material is
much more pronounced to the north of City Drain.  The unlined, southwest/northeast trending
storm water ditch empties into the City Drain west of Interstate 215.  The water level in this ditch
is approximately two feet below the water level in the shallow aquifer, providing the other shallow
ground water collection point which empties into City Drain.   Together with direct underflow,
the sanitary sewer and the unlined stormwater ditch ensure all shallow ground water beneath the
Site discharges to the City Drain.

Together, the City Drain, Surplus Canal, sanitary sewer, and the unnamed stormwater ditch on
the west end of the Site serve as ground water 'boundaries" for the contaminated shallow aquifer.
The effect of these  complex ground water interceptions, the upper clay layer, and the upward
vertical gradient across the clay layer is to contain the ground water contamination largely within
the site borders and only in the shallow unit. No elevated  concentrations (relative to naturally
occurring levels) of contaminants have been found in ground  water outside the Site boundaries or
in the intermediate aquifer.   The only contamination leaving the Site exits as surface water via the
City Drain, but is so diluted its presence is not detectable.  The City Drain discharges to the Great
Salt Lake,  specifically the Farmington Bay Waterfowl Management Area.

As stated previously, CKD and contaminated surface soil (OU1 and OU2) overlying the Site were
excavated.  The Site was backfilled with clean soil and regraded nearly level. This effectively
removed the entire  source  of the ground water contamination. However, significant levels of
contaminants still remain in the ground water, both dissolved  and adsorped to the sediments.
 Record of Decision                                                                PtgcNo. 12
 Portland Cement Supcrfiind Site
 Operable Unit Three

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6.0 SUMMARY OF SrrE(OU3) RISKS

6.1 CONTAMINANTS OFCONCERN

Contaminants of concern (COCs)  are  a subset  of all  contaminants that individually present
relatively high human health or environmental risks.  The COCs identified by UDEQ and EPA at
the Site are arsenic, cadmium, chromium, manganese, molybdenum, lead, and pH (a water quality
parameter). Human toxicity information or ARARs are available for all of the COCs except for
pH, which has been retained as a COC due to the high alkalinity of Site ground water (pH > 8)
and the associated potential for irritation to mucous membranes in exposed individuals.

EPA and UDEQ agree that ingestion of contaminated ground water (the only media addressed in
OU3) presents the primary health threatening exposure pathway and presents an immediate and
unacceptable risk to any future residents of the Site.  The number of potential future residents
affected by this pathway is unclear.

Of all the COCs present at the Site, arsenic is the most widespread at concentrations exceeding
the Federal Maximum Contaminant Level (MCL)  established under the Safe Drinking Water Act
(SDWA).  All  COCs  in the ground water roughly mimic the distribution pattern of arsenic,
although with less significant exceedances of their MCLs.  Therefore, arsenic levels were deemed
a 'Worst case" representation of the magnitude and extent of contamination in the shallow ground
water and were used as a basis for all predictive modeling.

63LEVEL ANDEXTENT-orCONTAMINATION

Studies on the extent of ground water contamination indicate that water in the shallow aquifer has
been impacted  over the  entire Site, with the highest  degree of contamination occurring in
locations formerly overlain by CKD deposits. As  discussed previously, surface water channels in
and around the Site create natural barriers to the migration of contaminated ground water and no
impacts have been observed in off-site ground water. Likewise, the clay layer separating the
shallow and intermediate  aquifers - and the associated  upward vertical gradient - prevents
downward  migration of contamination.   No impacts have been observed in the intermediate
aquifer.

Figure 6-1 illustrates the distribution of arsenic in OU3 ground water. Again, the distribution of
arsenic is considered representative of the maximum aerial extent of contamination for all COCs.
Two distinct arsenic plumes are apparent and originate from the former CKD deposits on Sites
Two and Three (the southeast and northeast CKD deposits respectively). A more diffuse arsenic
plume is  located on the West Site and is inferred to have resulted from leachate generation from
CKD deposited on the West Site and also from migration of the plume originating on Site Two.
Record of Decision                                                              Page No. 13
Portland Cement SuperAnd Site
Operable Unit Three

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               \AfeN toalloni, VtMl Mime.
               Anilyte Connntntfon
      IIJ' '1   S Q005 pprn -
             eoneenlMBoo below If -CM
             anoer r
      W*lll Instilled by Roy f. VNtiton, Inc.
      Swnmec 1995. Reported vvlua (used on
      man of three Mmpln collected In July
      md August, 1995. Other vikw biied on
      mMn J'~	"	•
            ~"* ••"••" '     	
            four or Aw quarterly umplct
                     id IJ94.
     -RlikeiHnumbiicdan upper conDaVrioi at
     man ire dlicuiied In tn 'Drift Hunm Health
     BI.L r  •
     	... »....ui QOOS ind i O.OS ppm
             conrantriUon below MCI

             > QOS and S OS ppm

             > Q5 ind  S 5-ppm

             > S ind S 50 ppm
    Mip and irulytlnl ditl prwHrJed by URS. W9J.

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As  discussed  previously,  potentiometric head measurements indicate shallow ground water
discharges  to the City Drain, the  north-south trending  sanitary sewer, and  the unnamed
stormwater  ditch on  the  west side  of the Site.   The  concentration contours support this
interpretation.  The arsenic plume on  Site Three is truncated at  the  north-south sewer line.
Ground water at this location is discharging to the presumed high permeability material in which
the pipe is embedded  or, possibly, to the sewer pipe itself.  The difiuse plume originating from
Site Two and the West Site is truncated at both the City Drain and the unnamed stormwater ditch.
Based on this analysis, under current conditions the shallow contaminant plume appears to be well
contained by discharge  boundaries.  This  containment allows the  classification of the ground
water as a low-level threat  waste (principal threat wastes included the CKD addressed in OU1 and
OU2).

Because the plume is contained, the volume of impacted water can be estimated.  Assuming a
saturated thickness of 30 feet and an areal extent of 61.5 acres, an estimated 461 acre feet of
ground  water is  contaminated with  arsenic at  concentrations  exceeding  the  preliminary
remediation goal of 64 micrograms per liter.

No surface  water  impacts are evident.   The Surplus Canal is a losing stream  at all times and
receives no contribution from contaminated ground water.   Though all contaminated ground
water eventually discharges to the City  Drain, its  impact is minimal The effects of dilution and
the slow rate of ground water discharge  make  the  presence  of additional arsenic  nearly
undetectable.   During  the  Remedial Investigation, measurements taken both upstream and
downstream of the Site showed no difference in arsenic concentrations.  Modeling conducted as
part of the Focused Feasibility Study (FFS) indicates that ground water discharge is slow enough
to preclude  hazardous levels of arsenic from ever being discharged to City Drain. The effects of
dilution are  more pronounced the farther downstream one moves from the Site. No other surface
water features (other  than the stormwater  ditch which empties directly into City Drain) receive
flow from the contaminated ground water.

6.3 CANCER RISKSFKOMCONTAMINATED GROUND WATER

Arsenic is the only COC identified for this she which is known to be carcinogenic when ingested.
Cancer  risk is described as the probability  that an exposed person would develop cancer before
age 70 as result of exposure to site related contamination.  In  this case, if shallow ground water
were used by future residents for drinking, the cancer risk for a reasonably maximally exposed
individual may be greater  than 1 out of 1000 at 16 of 21 on-site wells.  The cancer risk may also
be  greater than 1 out of 10 for 6 of 21 on-site wells.   A complete analysis and discussion of
cancer risk can be found in the Streamlined  Human Health Risk Evaluation (SRE) and FFS.

6A ACITIE (NON-CANCER) RISKS FROM CONTAMINATED GROUND WATER
Record of Decision                                                              PtgcNo. IS
Portland Cement Sopcrfund Site
Operable Unit Three

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The risk of non-cancer health effects (such as decreased liver function)  from a chemical  is
expressed as its Hazard Quotient (HQ).  If the value of the HQ is equal to or less than one, h is
accepted that there is no significant risk of non-cancer health effects.  If the value of the HQ
exceeds one, a risk of non-cancer health effects may exist, with the likelihood increasing as the
HQ increases.   As shown in Table  6-1, all COCs (except lead which is evaluated separately)
exceed an HQ of one in many portions of the Site for reasonably maximally  exposed individuals.
A complete analysis and discussion of non-cancer risk can be found in the SRE.
                                       Table 6-1
CHEMICAL OF
CONCERN
Arsenic
Cadmium
Lead
Chromium
Manganese
Molybdenum
NUMBER OF WELLS
WITH HAZARD
QUOTIENT GREATER
THAN ONE
20/21
1/21
N/A
4/21
3/21
17/21
MAXJMUMHAZAXD
* QU&IIENT
DETECTED
1000
2
N/A
20
100
1000
Lead in the ground water may also be of concern. The potential health risks from lead are posed
primarily to children who may be future residents at the Site.  These risks were evaluated using
EPA's Integrated Exposure, Uptake, and Biokinetic Model  (IEUBK)  with standard  default
values.   At most wellsi the risks  from lead were low, with less than a 5% chance that a child
ingesting ground water from that particular well would have a blood lead value above the EPA's
and the Center for Disease Control's blood level of concern (10 micrograms lead/deciliter blood).
However, five of the on-site wells would pose a risk between 5% and 10%  and one well would
pose a risk of 100%.

There are no methods for quantifying risks associated with the ingestion of water with high pH,
but values greater than 8.5 may cause irritation to the mouth, throat, or stomach. Fifteen of the
wells have pH values greater than 8.5.

6.5 ECOLOGICAL RISK

No ecological risk has been identified  for  OU3.    Surface  features  have been completely
remediated and, as such, there are no natural habitats associated with the Site.   Therefore, no
ecological risk assessment was completed for OU3.  The impacts to City Drain, the only surface
 Record of Decision
 Portland Cement Supcrfimd Site
 Qpenble Unit Three
PtgeNo. 16

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water feature receiving contaminated ground water, are minimal as discussed above and decrease
with distance from the Site. No impacts attributable to the Site are expected in Farmington Bay,
as contain: nant levels discharging to City Drain are far below levels established for protection of
fauna.  However, detailed standards were adopted to ensure protection of the City Drain and its
discharge area and are discussed in Section 6.6 below.

6.6 REMEDIAL ACTION OBJECTIVES

The  risks discussed  above provide the basis for EPA's decision that the contaminated ground
water at the Portland Cement Site presents an imminent and substantial endangerment to public
health and that remedial action is warranted.  The nature of these risks lead to four cleanup goals
or Remedial Action Objectives  (RAOs).  In accordance with the National Contingency Plan
(NCP), EPA and UDEQ have determined that the RAOs at this site are:

       •  Prevent human exposure to Site ground water that would result in an excess
       cancer risk equal to or exceeding 1 x 10"* (one additional cancer per million
       persons) or a hazard quotient exceeding one for a reasonably maximally exposed
       individual.

       •  Prevent off-site migration of contaminants to protect uncontaminated ground
       water.

       •  Restore ground water to its beneficial use to the extent practicable.

       •  Prevent unacceptable impacts to surface water associated with the Site.

To achieve these objectives, it is crucial to define  and  understand the anticipated future land use
on and  near  the Site.  Currently, the Site is undeveloped  and does not have any specific
residential, industrial,  or recreational  use.   The Site is currently  zoned  commercial and is
surrounded by commercial/industrial properties to the north, south, and west.  Commercial and
residential land use exists to the east.
                                   »

Typically, both commercial and residential land use would be considered plausible for the Portland
Cement Site based on current zoning and surrounding land use. Because the surface soils of the
Site  have been remediated to  a  level suitable for  future residential use, the presumed future use
for OU3 is residential and cleanup levels were considered in that regard.

It is  also crucial to determine the media specific cleanup levels which will result in attainment of
the stated RAOs. These remediation goals can be arrived at through consideration of applicable
or relevant  and appropriate regulations (ARARs), through the  use of  health-based goals, or
Record of Deeisioa                                                                Page No. 17
Portland Cement Supcrfund Site
Operable Unit Three

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through consideration of local background water quality.    All were considered for OU3 and
applied on a case-by-case basis for each COC. Each "standard' is described below.
ARARs

With respect to beneficial uses of ground water at the Site, the State classifies the ground water as
Class HB, a potential source of drinking water.   As such, Federal MCLs are potentially relevant
and appropriate.  The MCLs for each COC are shown in Table 6-2 below:
                                       Table 6-2
                               Federal MCLs &r COCs
nrmtAA ' t


Arsenic
Cadmium
Chromium
Lead
Manganese
Molybdenum
PH
.-.^tf&KL^fs
f //l/i Jlt}fjJJiillilir\L>llCr/

50
5
100
15
501
NA2
NA2
                        1. Secondary MCL; not based on health protection.
                        2. No MCL exists.
 Health-Based Goals

 Section 121  of CERCLA mandates that the selected remedy be protective of human health and
 the  environment, therefore  consideration  of health-based goals is  warranted.   For Portland
 Cement, health-based  goals were derived from the maximum allowable concentration  of a
 contaminant  deemed to provide a cancer risk no higher than 1 x 10"* or an HQ no higher than one
 for a reasonably maximally exposed resident;  These goals were based on cancer effects for
 arsenic and non-cancer effects for other COCs.  The methods used to determine health-based
 goals are discussed further in the SRE.  Health-based goals for a resident are shown in Table 6-3
 below:
 Record of Decision
 Portland Cement Superfimd Site
 Operable Unit Three
Page No. 18

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                                       Table 6-3
                          Health-Based Goal fora Resident
Cantammmt


Arsenic
Cadmium
Chromium
Lead
Manganese
Molybdenum
PH
Health-Based Goal
(tnicrograins/Lfter)

.05
18
182
20
182
182
<8.0
Background Water Quality

EPA  Publication 9234.2-01/FS-A,  'General  Policy,  RCRA,  CWA,  SDWA,  Post-ROD
Information and Contingent Waivers," states that if attainment of Federal MCLs is impossible
because the background level of the chemical subject to CERCLA authority is higher than that of
the standard, attainment is not relevant and appropriate.  Thus, it is critical to examine naturally
occurring background levels of contaminants at the Site. Naturally occurring background levels
for each COC are shown in Table 6-4 below:

                                       Table64
                          Local Background Water Quality*
\ftfTttSfttttt3Itt

\
Arsenic
Cadmium
Chromium '
Lead
Manganese
Molybdenum
PH
Background
SlLt * U!_ 1_ 1_ U1J11_ fT .Vjwl
I ..w.,j.n,.—,.,-*j. .iimj

64
6.2
24
1.9
440
63
7.8
                        1. UCLw of the mean of concentration values from wells
                        P3L, P3H, BIS, and P2I assuming a lognormal distribution.
Record of Decision
Portland Cement Supcrfund Site
Operable Unit Three
Page No. 19

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Again, these three 'Standards" (MCLs, health-based goals, and local background water quality)
were  applied on a case-by-case basis for each COC to determine  the  cleanup goal.   For
contaminants where local background concentrations exceed the MCL, the MCL was not deemed
relevant and  appropriate, and the cleanup goal shall only be  the  attainment  of background
concentrations. If local background concentrations are below the MCL, the cleanup goal shall be
the more protective (lower) of the MCL and health-based goal. For pH, the cleanup goal shall be
attainment of water with a pH lower than 8.0, which is below the threshold for potential mucous
membrane irritation.  Using this rationale, the final cleanup goals for each COC are shown below
in Table 6-5:
                                       Table 6-5
       Cleanup Goals for Contaminants of Concern at Portland Cement OU3.
flnnfjtminanf
'. •: '••.'{••.-.•::..- :•'••''•'.. '• '•'

Arsenic
Cadmium
Chromium
Lead
Manganese
Molybdenum
PH
Health-Based
Goaf fora
Resident
MCL
Local
Background
Water Quality1
rUfsnan
Goal
All concentrations in micrograms of contaminant per liter of ground water.
.05
18
182
20
182
182
<8.0
50
5
100
15
503
NA4
NA
64
6.2
24
1.9
440
.63
7.8
64
6.2
100
15
440
182
<8.0
1. Based on cancer effects for arsenic and non-cancer effects for all other chemicals.
2. UCL9S of the mean of concentration values from wells P3L, P3H, BIS, P2I, assuming a lognonnal distribution.
3. Secondary MCL; not based on health protection.
4. No MCL exists.                    >

It is also important that surface water quality in City Drain  be protected.    This is  achieved
through the establishment of alternate concentration limits (ACLs) which are to be enforced  at
the  ground  water  discharge  boundary.    Section   121(d)(2)(B)(ii)  of the Comprehensive
Environmental  Response Compensation and Liability Act (CERCLA)  allows  EPA to  establish
ACLs to those limits otherwise applicable under the following conditions:

    The ground water must have a known or projected point of entry to surface  water with no
    statistically significant increase in contaminant  concentration in the surface water  from
    ground water to the point of entry, or  at any point where there is reason  to  believe
Record of Decision
Part/and Cement Supcrfund Site
Operable Unit Three
ftgcNo. 20

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   accumulation of constituents may occur downstream.  In addition, the remedial action
   must include enforceable measures that will preclude human exposure to the contaminated
   ground water at any point between the facility boundary and a known and projected point
   of entry of such ground water into surface water.

Both  EPA and UDEQ  agree the Portland Cement  She satisfies these criteria  and that the
establishment of ACLs  for the purpose of protection  of water quality in the City Drain  is
appropriate. The City Drain is classified as Class VI surface water by the State and discharges to
the Great Salt Lake (specifically the Farmington Bay Waterfowl Management Area).  Discharge
requirements for Class VI  waters  are determined on a  case-by-case basis.  The performance
standard determined by UDEQ for Portland Cement is that the in-stream concentrations at the
point  of compliance (confluence of City Drain and north-south trending ditch west of 1-215) will
not exceed  125%  of the Class  HID  water  standards.    Class HID is set to be  protective of
waterfowl, shorebirds, and other  water-oriented  wildlife and the associated food chain.  To
establish  numeric standards,  denoted  here  as  ACLs,  UDEQ  calculated  the  individual
concentrations of chemicals (including COCs) in ground water at the Site which, if discharged to
the City Drain, would cause exceedance of the performance standard at the point of compliance.
These site-specific ACLs are shown in Table 6-6.

It is important to understand that for Portland Cement, ACLs are applied only for the protection
of the City Drain and are only appropriate where the ground water discharges to the City Drain.
The she-wide cleanup standards (Table 6-5) are substantially more stringent goals; ACLs in this
case are only safeguards which serve to protect City Drain and are enforced only at or near
ground water discharge points (along the City Drain, at the unlined storm water ditch, and near
the sanitary sewer).   The remediation will be considered complete only when cleanup goals
(Table 6-5) are achieved throughout the Site.

A more detailed explanation of ARARs applied to OU3 is found in Appendix A.

                                       Tablet*
        Alternate Concentration Limits (ACLs) for Discharges to City Drain
Chemical


Aluminum
Arsenic
Cadmium
Chromium HI
Chromium VI
Copper
Iron
ACL -•»•

••(oucfogmns per utcff
4,502.33
9,832.68
139.08
26,339.81
569.26
1,564.5
25,875.48
'•• '•'•- '; ''{^BQIXfG&f
.-.•:•:•:•'':'•'
•••••-••••••
Lead
Mercury
Nickel
Selenium
Silver
Zinc

ACZ*--'"<*-&^:
. , •.'?;*:?:.; :y2y^v::
(nuougnuns per jucfj
666.71
.62
20,667.94
258.75
6.21
13,914.05

Record of Decision
Portland Cement SuperAad Site
Operable Unit Three
PtgcNo. 21

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7.0REMEDIAL ALTERNATIVES

7.1 DESCRIPTION OF ALTERNATIVES

This section describes the alternatives EPA and UDEQ believe are technically implementable and
potentially able to meet the agencies' remedial action objectives at this she.  These alternatives
were arrived at through a systematic screening process beginning with the FFS.  In the FFS, many
remedial alternatives are screened and those that are most reasonable are retained and investigated
in detail.  Using this investigation, the ROD continues the evaluation and documents the decision
making  process.   The numbering  system  for  the alternatives discussed in this  ROD  (i.e.
Alternative One, Alternative Two,  etc.) is taken from the numbering of alternatives explored in
the FFS for OU3.  This allows interested parties to cross reference information between this
decision document and the FFS.

All  of the  remedial  technologies initially considered in the  FFS  are identified in  Table  7-1.
However,  only those technologies which were retained as part of the alternative development
process are described in detail for this document.  The alternatives are:

Alternative One: No Action

It is required by law that the EPA evaluate the consequences of taking no action.  This evaluation is
intended to provide decision makers and the public a basis upon which all of the remedy alternatives may
be compared. In this case, "no action" would include ground water monitoring of the shallow and
intermediate aquifers, but no active ground water treatment or institutional controls to restrict future land
uses. Natural processes such as flushing and dilution will be relied upon to reduce contamination levels.

Alternative Two. Monitored Natural Attenuation

  The "monitored natural attenuation" alternative is similar to the "no action" alternative except that it
  includes formal ground water use restrictions (deed restrictions) as an institutional control to prevent
  human exposure to ground water until OU3 remediation goals are achieved.   This alternative also
  relies on natural processes to contain contamination on-site and gradually reduce contaminant levels
• over time. The institutional controls wduld be implemented and enforced by the Federal Government
  and State of Utah.  Ground water and surface water will be monitored until remediation goals are
  achieved to ensure the efficacy of the remedy.

Alternatives Three A.B, andC.  Ground water Collection, Treatment by Precipitation, and Discharge to
Surface Water at Varying Pumping Rates

  This alternative considers ground water extraction at varying rates (19, 27 and 37 gallons per minute)
  from some or all of the three subsections of the Site. Extracted water would be treated using above-
  ground physical/chemical processes to reduce the pH and dissolved contaminant concentration through
  precipitation of the heavy metals. The treatment system would be constructed on-site and treated water
  would be discharged on-site to the City Drain. Resulting sludge (assumed  to be RCRA hazardous
Record of Decision                                                                  Page No. 22
Portland Cement Supcrfuad Site
Operable Unit Three

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  waste) would be transported directly to a RCRA Subtitle C treatment, storage, and disposal facility
  (TSD) fr- final disposition.  Institutional controls restricting ground water usage and ground water
  monitor: .•  would remain in force until contaminant concentrations meet or exceed the remediation
  goals.  Treatability studies were performed and are discussed in the FFS.

Alternatives Four A, B, and C: Ground water Collection, Treatment by Distillation, and Discharge to
Surface Water at Varying Pumping Rates

  This alternative is identical to Alternative Three except that the above-ground treatment method will be
  distillation.  This technology will permit additional removal of contaminants and IDS beyond that
  achievable  through precipitation and will generate a less hazardous sludge (assumed RCRA non-
  hazardous), though in very high quantities.  Sludge would be tranported to a RCRA Subtitle D storage
  facility.
Record of Decision                                                                      P»gc No. 23
Portland Cement Superfund Site
Operable Unit Three

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                                                Table 7-1.
                       Remedial Technologies Evaluated by EPA and UDEQ
Geaenl RaaeduJ .
Technology
No Action
Natural Attenuation

Containment
Ground water Extraction
•
Ground water Treatment






Treated Water Disposal


Secondary Sludge
Management


: Process Option
Ground water monitoring
Ground water monitoring
Water use restrictions
Slurry Wall
Interception Trench
Extraction
pH adjustment
Sedimentation
Filtration
Reverse osmosis
Strong base anion exchange
Immobilized ligands
Distillation
Surface water discharge
Injection
POTW discharge
On-site stabilization and disposal
(Subtitle D landfill)
Off-site treatment and disposal
On-site evaporation ponds

-
Retained per CERCLA guidance
Retained as representative process option.

Not retained. Hydraulic boundary exists at Site.
Potentially applicable.
Potentially applicable and retained as representative
process option.
Retained as representative process option.
Retained as representative process option.
Retained as representative process option.
Not retained due to probable membrane fouling from high
TDS.
Not retained; non-selective for COCs.
Not retained; non-selective for COCs.
Retained for further evaluation.
Potentially applicable; retained as representative site
option.
Potentially applicable but not retained due to potential
negative impacts on lower aquifer.
Potentially applicable but not retained bffaurf POTW
will not accept TDS concentrations
> JOOOmg/L
Potentially applicable but not retained due to economic
reasons.
Potentially applicable; retained as a representative site
option.
Not retained due to large land requirements.
Alternatives described as "Retained" or "Not Retained" refer to those cleanup approaches which were included (retained) for
consideration in the Focused Feasibility Study (FFS) or not  Only those alternatives described in the preceding discussion of
this section were considered promising enough to be carried forward for discussion in the Record Of Decision. Additional
information on all alternatives is located in the FFS.
Record of Decision
Portland Cement Superfijnd Site
Operable Unit Three
PtgcNo. 24

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7J2 DETAILED ANALYSIS CRITERIA

To  facilitate a complete and systematic screening (Section 7.3), each of the four alternatives
discussed in this Record of Decision is evaluated against nine criteria as set forth in the National
Contingency Plan (NCP).  Of these nine criteria, the first two are considered 'threshold factors"
which must be satisfactorily met in order for a remedy to be considered for implementation. The
next five criteria are considered 'primary balancing factors" and are the primary criteria  upon
which the analysis is based. Finally, the last two criteria (State and Community Acceptance) are
considered "modifying factors."

Threshold Factors

/. Overall Protection of Human Health and Environment

   Evaluation of the overall protectiveness of an alternative focuses  on whether a specific
    alternative achieves adequate protection and how site risks  are eliminated, reduced,  or
    controlled.  This evaluation also allows for consideration of whether an alternative poses
    any unacceptable short-term impacts.

2. Compliance with ARARs

    Laws, regulations, and ordinances from the federal, state, and local governments may  be
    applicable or relevant and appropriate for many matters affecting the implementation of a
    remedy.   These laws,  regulations, and ordinances are generally referred to by EPA  as
    ARARs (Applicable or Relevant and Appropriate Requirements). The chemical, location,
    and  action  specific ARARs are discussed along with  any other appropriate criteria,
    advisories, and guidance as they apply to each alternative.

Prinmw Balancing Factors

3. Long-Term Effectiveness and Permanence
                                   *

    This evaluation criterion involves consideration of potential risks that may remain after the
    site has been remediated and the ability of a remedy to  maintain reliable  protection  of
    human health and the environment over time.

4. Reduction ofToxicity, Mobility, or Volume of Contaminants

    There is a statuatory preference for remedies that permanently or significantly reduce the
    health hazards (toxicify), movement of contaminants (mobility), and quantity (volume)  of
    contaminants.
Record of Decision                                                               Page No. 25
Portland Cement Supcrfimd Site
Operable Unit Three

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5. Short-Term Effectiveness

   The focus of this criterion is the protection of the community, environment, and the
   workers during remediation.

6. Implementability

   This criterion establishes the practical aspect of implementing an alternative.

7. Cost

   The cost (capital, operation, and maintenance) of an alternative is an important, practical
   criterion in evaluating potential remedies.

Modifying Factors

8. and 9. State and Community Acceptance

   Community acceptance is addressed through means of a public meeting, an open public
   comment period, and ongoing community participation activities.  The State may concur,
   oppose, or have no comment regarding the decision. These factors will be discussed only
   in Section Eight, Summary of the Comparison of Alternatives.


73 DETAILED ANALYSIS OF ALTERNATIVES

7.3.1 Alternative One - No Action

Overall Protection of Hun?an Health and the Environment

Ground water contamination presents a health risk if ingested as drinking water.  However, it is
unlikely that local ground water will be used for human consumption without prior treatment due
to naturally occurring contamination (arsenic, total dissolved solids, etc.) at levels above drinking
water standards. Nonetheless, human exposure to ground water at most areas of OU3 should be
avoided, but the No Action alternative has no provision for the prevention of human exposure to
Site ground water and does not offer sufficient protection of human health.

This alternative relies on natural flushing and dilution of the  shallow aquifer and the ongoing,
gradual discharge of contaminated ground water to the City Drain as the principal mechanisms for
achieving ground water restoration. Data generated in the Remedial Investigation (RI) and FFS
indicate that the water quality in the City Drain would not be degraded through implementation of
this alternative.
Record of Decision                                                              Page No. 26
Portland Cement Supcrfuod Site
Operable Unit Three

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Ground water contaminant transport modeling conducted under the FFS indicates that the ground
water discharge rate from the shallow aquifer (within the Site) to the City Drain is approximately
20 gallons per minute (gpm). The flow measured in City Drain during the RI was approximately
449 gpm. A comparison of these flow  rates suggests that impacts to water quality in the City
Drain due to discharge of contaminated ground water are negligible due to dilution.   In feet,
during the RI, flow and arsenic concentration measurements were taken in the City Drain in
locations upstream and downstream of the Site.  The data indicate no discernable difference in
either flow or arsenic concentrations from the upstream to the downstream locations.

As discussed in Section 6.6, ACLs were established for the protection of City Drain. However,
because the  source of contamination has been completely removed (OU1 and OU2) and current
maximum concentrations of contaminants are already below ACLs, the possibility of exceeding
ACLs at any point on the Site is remote.  However, establishment of ACLs provides an extra
measure of protection for the City Drain.

Compliance  with ARARs

Chemical-specific ARARs  (Federal MCLs) exist for select Contaminants  of Concern in ground
water (except pH).  As discussed in Section 6.6, the Federal MCL was deemed relevant and
appropriate  ONLY for contaminants for which the background water quality did not exceed the
MCL.  Under the No Action alternative, it is expected that natural  flushing and dilution of the
ground water will ultimately result in compliance with relevant MCLs.   However, predictive
modeling suggests that attainment of cleanup standards under this alternative will require longer.
than 100 years.

Chemical-specific ACLs were also established to ensure  protectiveness of the City Drain and
Farmington Bay WMA. Because maximum ground water concentrations for all COCs are already
lower than ACLs and the source of contamination has been removed, this alternative will result in
compliance with ACLs.

No location  specific ARARs were applied.

This alternative does not involve active remediation, therefore no action-specific ARARs were
applied.

Appendix A of this document gives a complete description of chemical,  action, and location-
specific ARARs applied to OU3.
Record of Decision                                                              Page No. 27
Portland Cement Supcrfund Site
Operable Unit Three

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Long-Terna Effectiveness and Permanence

Under this alternative, significant risk remains for a long period of time (more than 100 years)
under any potential drinking water scenario.   However, both EPA and UDEQ  agree that site
conditions and natural processes will be fully successful in reducing contaminant concentrations to
cleanup goals  over the long-term.   Flushing and dilution will continue to  decrease the
concentrations  of contaminants,  but  even background  water quality, when achieved, would
require  significant treatment prior to  use as drinking water.    This alternative provides no
institutional controls over the long-term to prevent exposure to ground water, making the long-
term effectiveness of this remedy poor.  It is anticipated that once contaminant  concentrations
reach remediation goals, improvement in ground water quality would be permanent.

             rbxicityT Mobility, or Vc

In this alternative, there is no active remediation process (treatment, containment, or otherwise)
for reducing the toxicity, mobility, or volume of contaminated ground water.  However, natural
processes and existing features serve to contain the contamination on-site and  will ultimately
reduce the toxicity (due to dilution) and volume of contaminants.

Short-Tenn Effectiveness

Workers face minimal physical and chemical hazards during the  installation and sampling of
monitoring wells; however, these hazards are manageable through administrative and engineering
controls.  There is also a risk of contaminating the intermediate aquifer and the deeper, principal
drinking water aquifer by drilling through the contaminated shallow aquifer.  Proper  drilling
techniques and the existence of an upward vertical hydraulic gradient will greatly reduce the risk
of cross-contamination of aquifers.

Implementability

There are no technical or administrative obstacles to implementation of the No Action alternative.
                                   t
Costs

The 100 year present worth cost is estimated at approximately $560,000; most of which  is
operation and  maintenance  cost associated  with  ground water monitoring.     Detailed  cost
comparisons are found in Table 8-2.
Record of Decision                                                                Page No. 28
Portland Cement Superfund Site
Operable Unit Three

-------
      Alternative Two - Monitored Natural Attenuation - The Selected Remedy

            ctign of Hii"inn Health and the Et

This alternative also relies on natural flushing and dilution of the shallow aquifer and the ongoing,
gradual discharge of contaminated ground water to the City Drain as the principal mechanisms for
achieving ground water restoration.  However,  this alternative adds an additional measure of
protection through the use of formal institutional controls to restrict the use of contaminated
ground water for drinking purposes.  This addition, along with the implementation of the ACL,
makes Alternative Two sufficiently protective of human health and the environment.

Compliance with ARARs

As  discussed in  Section 7.3.1,  the Federal MCL was deemed relevant and  appropriate as a
chemical-specific requirement only for contaminants  for which the background  water quality did
not exceed the MCL.  Under the Monitored Natural Attenuation alternative, it is expected that
natural flushing and dilution of the ground water will ultimately result in compliance with relevant
MCLs. However, predictive modeling suggests that attainment of cleanup standards under this
alternative  also will require significantly more than 100 years.   Modeling was conducted to
estimate arsenic concentrations at 50 and 100 years.  Figure 4-2 illustrates the current distribution
of arsenic in ground water. Figures 7-1 and 7-2 illustrate the arsenic concentration expected at SO
and 100 years in the future, respectively.  As seen from the figures, achieving background
concentrations for arsenic (and MCLs or health-based goals for other COCs) will take longer than
100 years.

Chemical-specific ACLs were also established  to  ensure  protection of the City Drain and
Farmington Bay WMA. Because maximum ground water concentrations for all COCs are already
lower than ACLs and the source of contamination has been removed, this alternative will result in
compliance with ACLs.

No location-specific ARARs were applied.
                                   i
This alternative does not involve active remediation, therefore no action-specific ARARs apply.

Appendix A of this document gives  a. complete description of chemical, action, and location-
specific ARARs applied to OU3.

Long-Tenn Effectiveness and Pep™nence

Under this  alternative, significant risk remains for a long period of time (more than  100 years)
under any potential drinking water scenario.   However, both EPA and UDEQ agree that site
conditions and natural processes will be fully successful in reducing contaminant concentrations to
Record of Decision                                                               Page No. 29
Portland Cement Superfimd Site
Operable Unit Three

-------
rsenic Distribution
                                                                                                           CKO Boundaries

                                                                                                           Deadlines

                                                                                                           Fence Llnei
                                                                                                          Mfell LoaHoni. V*ll Nime.
                                                                                                          Aiulyte ConantnHan
 I    '•:  •;SiS>Si|^^®^^^9^Jbi
J  •' :•;;  5.1 '&*$£&%& ••&ttW*^:
                                                                                                          > (1005  QOS ind £ 05 ppm

                                                                                                    f-'M' \  > 05 ind S 5 pom

                                                                                                          > S and A 50 ppin
                                                                                                    Mip (nd inilytkll dlt> fi'cvlded by URS, 1991
                                                                                                    • • V*lli (mailed by Roy F. V*)too, Inc
                                                                                                     Sumnxi; 1995 Reported viluef redeci tfw
                                                                                                     rtjulB of (he conumlnonl triniport model.
                                                                     :^mmm
                                                                                                       Pbrlland Cement Superfund Site
                                                                                                      Predicted Arsenic Distribution
                                                                                                            After 50 Years
                                                                                                          Natural Attenuation

-------
Kjredfcted Arsenic Distribution
                                                                                                                                                 OCD Boundarlo

                                                                                                                                                 Deed line*

                                                                                                                                                 fence llnei
                                                                                                                                                 V*lllocmoni,HM1N»me,
                                                                                                                                                 Amliw Concentration

                                                                                                                                          I    1  > 005 jnd S Oj ppm

                                                                                                                                         I*' '"•• I   > OS and S $ ppm

                                                                                                                                                 > 5 ind S SO ppm
                                                                                                                                        M»p and anilytlcal dia pnvldcd b» UR1 U91
                                                                                                                                        • - VWI. Inibllcd by Roy F. V*.(oo, Inc.
                                                                                                                                          Surnmet IWi.Repe^d wluet refleo di<
                                                                                                                                          nsulb a (h« conumlrunl irintpot model.
                                                                                                                                            Portland Cement Superfund Site
                                                                                                                                          Predicted Arsenic Distribution
                                                                                                                                                  After TOO Years
                                                                                                                                               Natural Attenuation

-------
cleanup goals  over the  long-term.   Flushing  and  dilution  will  continue  to decrease the
concentrations  of contaminants, but  even background  water quality, when achieved,  would
require significant treatment prior to use as drinking water.   However, the implementation of
institutional controls makes this alternative effective over the long-term.  It is anticipated that
once contaminant concentrations reach remediation goals, improvement in ground water quality
would be permanent.   Five  year  ROD  reviews  would  be  required  to ensure that adequate
protection of human health and the environment is maintained.

Reduction of Toxicity,. Mobility, or Volume of Contaminants

In this alternative, there is no active remediation process (treatment, containment, or otherwise)
for reducing the toxicity, mobility,  or volume of contaminated ground water. However, natural
processes and existing features serve to contain  the contamination on-site and will ultimately
reduce the toxicity and volume of contaminants.

Short-Tenn Effectiveness

Workers face minimal physical and chemical hazards during the installation and sampling of
monitoring wells; however, these hazards are manageable through administrative and engineering
controls. There is also a risk of contaminating the intermediate aquifer and the deeper, principal
drinking water aquifer  by drilling through the contaminated shallow aquifer.   Proper drilling
techniques and the existence of an upward vertical hydraulic gradient will greatly reduce the risk
of cross-contamination of aquifers.

Implementabilitv

There are no technical or administrative  obstacles to implementation of the Monitored Natural
Attenuation alternative.

Costs

The 100 year  present worth  cost is, estimated at approximately $630,000; most of which is
operation and  maintenance cost associated with ground water monitoring.    Detailed  cost
comparisons are shown in Table 8-2.

 7.3.3  Alternatives 3a, 3b, and 3c - Ground water Collection, Treatment by Precipitation, and
Discharge to Surface Water
Overall Protection of Htifn^n Health and the Environment
Alternatives 3 a, 3b, and 3c would offer protection of human health and the environment through
active ground water extraction and treatment. Because the rate of cleanup is proportional to the
Record of Decision                                                               P*gcNo.32
Port!and Cement Supcrfiind Site
Operable  Unit Three

-------
rate of ground water extraction, the protectiveness of the remedy increases incrementally from
Alternative 3a (19 gpm) through Alternative 3c (37 gpm).  Figures 7-3 through 7-8 illustrate the
expected arsenic concentrations for the three pumping options at SO and 100 years into the future
based on the results of predictive ground water transport modeling (discussed in more detail in the
EPS). Figure 7-8 indicates that even at maximum sustained pumping rates, arsenic concentrations
will still  exceed the agencies' remedial goals by over 100 times at 100 years into the future.  A
comparison of the predicted concentrations obtained via  this alternative with those predicted
using natural processes reveals only a marginal difference.

In addition to the ACL, this alternative provides an  additional  level  of protection for the City
Drain by capturing and treating ground water.

Compliance with ARARs

Again, the Federal MCL was deemed relevant and appropriate as a chemical-specific requirement
only for contaminants for which the background  water quality did not exceed the MCL.  Under
Alternative Three, active  extraction and treatment of the ground water will ultimately result in
compliance with relevant MCLs.   However,  predictive modeling suggests that attainment of
cleanup  goals with active treatment also  will require significantly more than 100 years.  The
results of this modeling are described in detail in the RI/FFS.

Chemical-specific ACLs  were also established  to ensure protection of the City  Drain  and
Farmington Bay WMA. Because maximum ground water concentrations for all COCs are already
lower than ACLs and the source of contamination has been removed, this alternative will result in
compliance with ACLs.

No location-specific ARARs were applied.

Because active remediation is being  conducted, several action-specific ARARs apply.  Proper
implementation of this alternative will result in  attainment of all action-specific ARARs.  The
remediation system would be constructed in accordance with the substantive requirements of the
.Resource  Conservation and  Recovery Act  (RCRA)  concerning handling of characteristic
hazardous wastes (extracted ground  water and  sludge residuals).  The  City Drain, which win
receive treated  water, is classified as Class Six  surface water by the State.   Though no Utah
Pollution Discharge Elimination System-(UPDES) discharge permit would be required (CERCLA
Section  121(e)(l) states that on-site actions require no permit), the selected remedy should meet
the SUBSTANTIVE requirements of a UPDES permit. For Portland Cement,  in accordance with
Section  121, only the substantive requirements were considered,  and as such,  this is NOT an
ARAR.  Numeric standards for treated  effluent prior  to discharge for Class  Six waters are
determined on a case-by-case basis by the UDEQ.   The performance standard determined by
UDEQ is  that  the in-stream  concentrations  at the confluence of City  Drain and north-south
trending ditch west of 1-215 will not exceed 125% of the Class HID water standards.  Predicted
 Record of Decision                                                               Page No. 33
 Portland Ccmcat Supcrfuad Site
 Operable Unit Three

-------
Predicted Arsenic Distribution
           After 50 Years
        ing Option A (18.5 gpm)
 legend	


  _-  -  CKO BoiimltflM

  	  Deadlines

        Fencellnei


        V*ll Locations, Mfetl Name.
        Anilyle Concentration




Concentrations Key	


  -^~j   > aoOS and S (UK ppm
       concentration below MCI

       > 005 and S OS ppm

       > 0.5 and  s 5 ppm

(gjgS  * * *'"' s 5" PPn)
                                                                                                                                     Map *nd Jnilyllal daa provided by URS. I99S.
                                                                                                                                     • • Wfelli Inttalled hy Rev F. Wttton, Inc.
                                                                                                                                       Summet 1995. Reported valuet rellea lh«
                                                                                                                                       mulb 
-------
                                                                                          legend
?:;Mi0;;-W

                                                                                                 CKO Boundailrt

                                                                                                 Otfdllnrt

                                                                                                 Fence I Inrs
                                                                                            t   W*M lonllonv VWI Njme.
                                                                                                Anjlyte Concmlratfun
                                                                                         CoocentriHent Key
                                                                                          • ~1  > 0005 «nd S DOS ppm
                                                                                                ConcenirtHoii below MCL

                                                                                         I    I  > nOS and S QS ppm

                                                                                                > OS UK) S 5 ppm

                                                                                                > $ 
-------
            CKD Boundirln

            Dwo Llnci

            Fence I Inei
            V»ll l.ocalloni. Wfell Hume.
            Analytc Conrenlnifoo
    I     I   > 0005 and S 005 ppm
           concentration below MCI
           > O.OS and S 0.5 ppm

   I   'I  > 0.5 and S  5 ppm

           > Sand £ 50 ppm
  Map and analytical data provided by UK. (995.
     V*tli Imtalled by Roy f. Wtiton, Inc.
    Summer, 1)95. Reported viluel re/leci Ihe
    reiulu of (he conUmlnint traniport model.
       Portland Cement Superfund Site
     Predicted Arsenic Distribution
             After 50 Years
     Pumping Option B (27 gpm)
FIGURE 7-5

DC* leott-OOMMn

-------

   [    "]  > (1005 »nd S ftOS pon
   ---  oononitiaHan Mow MCI
          > 005 ind fi OS ppm

   ["   |  > 05 and X 5 ppm

          > Sind S SOpptn
  Map tnd inilyllcil dan pmHdad by URS, 19*5.
    VWIi ImUlW by Koy F. Wblon, Inc.
    Summet 1995. 'Repotted wlun reflect (h«
    mults of the contaminant traniport model.
      Portland Cement Superfund Slle
    Predicted Arsenic Dlslribution
            After 100 Vfears
     Pumping Option B (27 gpm)
FIGURE 7-6


00* MMi-eOMMn

-------
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                                     Oeedltnei


                                     fence tlnei


                                     V*ll LoaHant, V*ll Name,
                                     Analyle ConcenlnHon
                                                                                                                     Concrntralloni Key
                                                                                                                                I~] > ttOOS md S 005 ppm
                                                                                                                                    concenlni)an below MCI


                                                                                                                                Z3 > QOS ind S OS ppm


                                                                                                                                  I > O5 «nd S S ppm


                                                                                                                              OSSC  > S «"d S 50 pnm
                                                                                                                    RefBieiitn
                                                                                                                    Mip ind arulytlal dm proHded by URS, IMi

                                                                                                                      Mtlli tmtalled fay Roy F. VMrilwv l»c
                                                                                                                     Summri; 1995. Repor*H xlun reflect (tie
                                                                                                                     mula ofihe conUmlruni tnnipol model.
                                                                                                                  FIGURE 7-7


                                                                                                                  Kit IOOM.007 Mta
                                                                                                                       ftwtland Cement Superfund Site
                                                                                                                     Predicted Arsenic Distribution
                                                                                                                            After 50 Years
                                                                                                                     Pumping Option C (365 gpm)

-------
                                                                                                                      CKO Boundirlei

                                                                                                                      DecdKnn

                                                                                                                      fencellnei
                                                                                                                      VWIlocitlant,vwiNtme,
                                                                                                                      Anilyte Canrvntiation •
                                                                                                                I   1 >OOOSird«Q«ppm
                                                                                                                     CDnoBnlntioo Mow MCI
                                                                                                                     > OOS *nd S OS ppm

                                                                                                                     > W ind S 5 pom

                                                                                                                     > Jind S 50 pom
 mm
Map ind inilyttctl did provided by UKS, t»i

• • V*)li Intuited hy Hoy F. MHlon,
 Summet tWt*epS
^«iiji?3:^^-^--:-. :?--«
:V," ',: .Trf-.;. .•V^^.riCi- i . :* ;.•: •••=•«'.:•' '.' '    '-.
                                                                                                                  Pbrtland Cemenl Superfund Slle
                                                                                                                Predicted Arsenic Distribution
                                                                                                                      After 100 Years
                                                                                                                Pumping Option C (365 gpm)


                                                                                                             FIGURE 7-fl


                                                                                                             OCM IOW100J4IOB,


-------
effluent quality for the precipitation process will likely meet Class TTTD  metals  standards but
would not meet a reasonable standard for reduction of IDS.  However, it should be noted that
Site ground water naturally discharges to City Drain, and any treatment would represent an
improvement (albeit immeasureable) to City Drain water quality.

Appendix A  of this document gives a complete description  of chemical,  action,  and location-
specific ARARs applied to OU3.

Lon-Tenn Effectiveness and
Under this alternative, significant risk remains for a long period of time (more than  100 years)
under any potential drinking water scenario.  Time periods to reach remediation goals under this
alternative would likely be less than those required when relying solely on natural processes;
however, long periods of time would still be required.   Th^s alternative also includes institutional
controls, and thus is also very effective over the long term.  It is anticipated that once contaminant
concentrations  meet  remediation  goals, the improvement in ground water  quality would be
permanent.
Under this alternative,  the mobility and volume of contaminants in ground water would be
reduced through extraction and treatment.   Contaminants would be precipitated, stabilized, and
disposed in a Subtitle C landfill, further reducing the mobility.

Short-Term Effectiveness

Workers would face chemical and physical hazards as a result of the operation and maintenance of
the water treatment and sludge handling facilities. Workers would be exposed to corrosive and
toxic metal fumes, as well as liquids and solids from strong acids and bases associated with
treatment chemicals and sludges.   Although these  risks are significant, they  are  controllable
through administrative and engineering means.

CKD and contaminated soils at the Site were removed.  Therefore, there is little risk of exposure
to contaminated soils or dust during construction or operation. Workers will need to take special
precautions to avoid contact with contaminated ground water during the installation of ground
water collection wells or trenches.

Implementability

Alternative Three construction activities are readily implementable, though extensive effort would
be  required.   The proposed ground  water collection and treatment method uses  common
construction methods  and  the chemicals required for treatment  are readily available in the Salt
Record of Decision                                                               Page No. 40
P&rtland Cement Superfijnd Site
Operable Unit Three

-------
Lake City area. The high IDS present in the ground water could pose fouling problems during
operation of the system.
The 100-year present worth costs for the three options (a, b, and c) are estimated at 9.1, 10.2, and
11.2 million dollars respectively. Detailed cost comparisons are found in Table 8-2.
4.3.4  Alternative 4a, 4bf and 4c - Ground water Collection  Treatment by Distillation, and
Discharge to Surface Water
       Protection of H»™»" Health and the
Alternatives 4a, 4b,  and 4c (similar to Alternatives 3a, 3*b, and 3c with  the exception that
treatment would be by distillation as opposed to precipitation) would offer protection of human
health and the environment through active ground water extraction and treatment.  Because the
rate of cleanup is proportional to the rate of ground water extraction, the protectiveness of the
remedy increases incrementally from Alternative 4a (19 gpm) through Alternative 4c (37 gpm).
The  rate of restoration  and  degree of protection would  be identical  to  that discussed for
Alternative Three, with the added benefit of complete removal of IDS by virtue of the distillation
process.

Compliance with ARARs

Again, the Federal MCL was deemed a relevant and appropriate chemical-specific regulation only
for contaminants for which the background water quality  did not exceed  the MCL.  Under
Alternative 4, active extraction and treatment of the ground water will  ultimately  result in
compliance with relevant MCLs.   However, predictive modeling suggests that attainment  of
cleanup goals with active treatment also will require significantly more than 100 years.  The
results of this modeling are described in detail in the RUFFS.
                                                     •
Chemical-specific ACLs  were also  established to ensure protection  of the City Drain and
Farmington Bay WMA. Because maximum ground water concentrations for all COCs are already
lower than ACLs and the source of contamination has been removed, this alternative will result in
compliance with ACLs.

No location-specific ARARs were applied.

Because active  remediation is being conducted, several action-specific ARARs apply. Proper
implementation of this alternative would result in attainment of all action-specific ARARs.  The
remediation system  would be constructed in accordance with Resource  Conservation and
Record of Decision                                                               Page No. 41
Port/and Cement Supcrfund Site
Operable Unit Three

-------
Recovery Act (RCRA) requirements for handling of characteristic hazardous wastes (extracted
ground water and sludge residuals). City Drain, which will receive treated water, is classified as
Class Six surface water by the State. Though no Utah Pollution Discharge Elimination System
(UPDES) discharge permit would be required (CERCLA Section 121(e)(l) states that on-site
actions require no permit), the selected remedy should meet the SUBSTANTIVE requirements of
a UPDES permit.  For Portland Cement, in accordance with Section 121, only the substantive
requirments were considered, and as such, this is NOT  an ARAR. Numeric standards for treated
effluent prior to discharge for Class Six waters are determined on a case-by-case basis by the
UDEQ. The performance standard determined by UDEQ is that the in-stream concentrations at
the confluence of City Drain and north-south trending ditch west of 1-215 will not exceed 125%
of the Class TTTD water standards.  Predicted effluent quality for the distillation process will meet
both Class HID metals standards and standards for reduction of TDS.

Appendix A of this document gives a complete description of chemical, action, and location-
specific ARARs applied to OU3.

Long-Tenn Effectiveness and Permanence

Under this alternative, significant risk remains for a long  period of time (more than 100 years)
under any potential drinking water scenario.  Time periods to reach remediation goals under this
alternative would likely be less than those required when relying solely  on natural processes;
however, long periods of time would still be required.  This alternative also includes institutional
controls, and thus is also effective over the long term. It is anticipated that once contaminant
concentrations meet remediation  goals, the improvement in ground water  quality would be
permanent.

Reduction in Toxicityr Mobility, or Volume of Con*atn'nants

Under this  alternative,  the  mobility and volume  of  contaminants in ground water would be
reduced through extraction and treatment.   A high degree of reduction  for all dissolved and
suspended solids, including metals, would be achieved in the extracted ground water. This allows
the cleanest water to be discharged to the City Drain.  However, the volume of contaminants in
the subsurface would decline at a similar rate to Alternative Three.  Sludge generated with this
process is not anticipated to be hazardous.

Short-Term Effectiveness

Workers would face physical hazards as a result of the operation and maintenance of the water
treatment and sludge handling facilities. Although these risks are significant, they are controllable
through administrative and engineering means.
Record of Decision                                                               Page No. 42
Portland Cement Superfund Site
Operable Unit Three

-------
CKD and contaminated soils at the Site were removed. Therefore, there is little risk of exposure
to contaminated soils or dust during construction or operation. Workers will need to take special
precautions to avoid contact whin contaminated ground water during the installation of ground
water collection wells or trenches.
Alternative Four construction activities are readily implementable, though extensive effort would
be required. The water treatment equipment is complex but adequate resources exist in the Salt
Lake City area to construct and operate the equipment.  Operation of the distillation equipment
would entail a very large energy demand, either electric or natural gas.  The high TDS present in
the ground water would result in high volumes of generated sludge, estimated at 90 times the
amount in Alternative Three.  However, the sludge is not anticipated to be classified as a RCRA
hazardous waste and could be disposed of at a Subtitle D facility.
                                                        (

Costs

The 100-year present  worth costs for the three options (a, b, and c) are estimated at 34.6, 36.1,
and 47.4 million dollars, respectively. Detailed cost comparisons are found in Table 8-2.
Record of Decision                                                                 Page No. 43
Portland Cement Svperfimd Site
Operable Unit Three

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8.0 SUMMARY OF THE COMPARISON OF ALTERNATIVES

A comparative analysis is conducted to evaluate the relative performance of each alternative in
relation to each specific  evaluation criterion.    This is in contrast to the detailed analysis of
alternatives in the previous section, in which each alternative was analyzed independently without
consideration of other alternatives. The purpose of this comparative analysis is to identify the
advantages and disadvantages of each alternative relative to one another to both decision-makers
and the public. Table 8-1  summarizing the comparison is located at the end of this section.

Overall Protection of HutPan Health and the Environment

Protection of human health  is provided by all four of the alternatives discussed in this document,
although at varying degrees.  Protection is achieved primarily through reliance on the fact that
Site ground water is not a current source of drinking water, nor is it likely to be a future source of
drinking water due to its  non-potable characteristics.   Additional protection is  provided  by
existing hydraulic barriers which effectively prevent the spread of contamination to unimpacted
areas (both off-site and  lower,  uncontaminated aquifers). Monitoring also serves to protect
unimpacted  areas of the  environment.   Protection  of surface  water  is achieved through
establishment of ACLs and monitoring to ensure they are not exceeded.

Alternative One offers the least protectiveness relative to the other alternatives because there are
no  formal institutional  controls to  prevent  future exposure.   This level  of protection  is
unacceptable.

Alternatives Two, Three, and Four offer a higher, and acceptable,  level of protectiveness because
institutional controls would be implemented.

Alternatives Three and Four offer a somewhat shorter remediation time than Alternatives One and
Two,  thereby lessening  duration of risk  and  affording a slightly higher level of protection.
Alternatives Three and Four also offer some containment advantages as a large portion of residual
contaminants would be placed in a secure RCRA landfill.

All alternatives offer similar degrees of protection of the environment.  Modeling indicates that
impacts to the City Drain will be negligible under all alternatives.  Alternatives One and Two rely
on  existing hydraulic barriers and conditions to prevent the spread of contamination to off-site
ground water and lower aquifers, whereas Alternatives Three and Four provide an extra measure
of protection due to active capture from pumping which reduces contaminant loading.
 Record of Decision                                                              Page No. 44
 Portland Cement Supcrfund Site
 Operable Unit Three

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Compliance with ARARs

A detailed description of ARARs applied for OU3  is given in Appendix A.   All  evaluated
alternatives would comply with all chemical, location, and action-specific ARARs.

All alternatives are expected to achieve  chemical-specific ARARS,  both relevant MCLs and
ACLs.

No location-specifc ARARs were applied to any of the alternatives.

Alternatives One and Two do not involve active remediation, and as such, there are no identified
action-specific requirements.   Alternatives Three and Four would be constructed as to comply
with all substantive action-specific requirements.

Lon-Tenn Effectiveness and
Residual risks  under all  alternatives will  remain significant  over the long-term;  however,
somewhat more timely risk reduction is afforded by Alternatives Three and Four. The degree of
improvement is unclear but marginal, at best Alternative One exhibits a lesser, and unacceptable,
degree of effectiveness and reliability relative to the other alternatives because no institutional
controls are provided. Institutional controls, which are components of Alternatives Two, Three,
and Four, will be reliable  if enforced.  Only minor government agency coordination would be
required to implement all alternatives. Once remedial goals are achieved, restoration under all
alternatives is expected to be permanent.
•Reduction in ToxJcJtv. Mobility, or Volume

Alternatives Three and Four provide a higher degree of reduction in  volume of contaminants
compared to Alternatives One and Two.  All alternatives affect the toxicity of the ground water
through dilution as contaminants are removed (essentially a reduction in volume).  Alternatives
Three and Four pose the additional problem of generation of sludge, with Alternative Three
producing a smaller volume of RCRA hazardous waste, and Alternative Four producing a higher
volume of non-hazardous waste.

Short-Tenn Effectiveness

Alternative One provides the least amount of short term effectiveness, as no institutional controls
will be in place while restoration is ongoing.   Short-term risks to workers implementing  the
remedy under Alternatives One and Two are lower than Alternatives Three and Four, though
these risks could be effectively managed through administrative and engineering controls.   No
alternative provides ground water restoration in less than 100 years.
 Record of Decision                                                               PtgeNo. 45
 Portland Cement Superfuod Site
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Implementabilhy

There are no major technical obstacles to the implementation of any of the remedial alternatives.
Alternatives Three and Four present extensively more effort in implementation, though both are
certainly achievable.  The high amount of TDS in the ground water will produce a very large
amount of sludge under Alternative Four.  TDS could also cause operational challenges in both
treatment alternatives.

 Cost

Detailed cost comparisons are found in Table 8-2. Only Alternatives Two, Three, and Four are
sufficiently  protective of human health and the environment and warrant comparisons of cost.
Alternatives Three and Four are not considered cost effective as neither would result in ground
water restoration in a substantially shorter time frame than Alternative Two; nor would they
provide any substantive increase in protection of human Health and the environment.  In other
words, the higher costs for Alternatives Three and Four are not commensurate with small level of
additional risk reduction afforded.  Alterntive Two is the most cost effective.
The UDEQ has worked in partnership with the USEPA throughout the RI/FS and accepts the
proposed remedy on the basis that it is technically impracticable to achieve MCLs in a reasonable
time frame.
The Proposed Plan was issued in January 1998. A public meeting was held on 21 January 1998 at
the UDEQ offices in Salt I-ake City, Utah.  One member of the community attended the meeting
and made  a  brief statement.  No opposition to the Proposed Plan  was expressed.   Written
comments and questions were received prior to the close of the public comment period.  Those
comments  and responses are presented in the Responsiveness Summary (Appendix B) of this
ROD.
Record of Decision                                                              Page No. 46
Portland Cement Superfimd Site
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                                       Table 8-1
                        Comparative Analysis of Alternatives
^•'?*z*f^.

Overall
Protectiveness
Compliance with
ARARs
Long-Term
Effectiveness and
Permanence
Reduction of
Toxicity,
Mobility, or
Volume of
Contaminants
Short-term
Effectiveness
Implementability
Costs
State Acceptance
Community
Acceptance
Alternative One
No Action

Poor
Yes
Poor
Fair
Poor
Easy
Low
Poor
N/A1
Alternative Two
Natural
Attenuation
Good
Yes
Good
Fair
Good
Easy
Low
Good
N/A1
Alternative TJzree
Treatment
Good
Yes
Good
Good
Good
Difficult
High
Fair
N/A1
AltemativcFour
Distillation
Good
Yes
Good
Good
Good
Difficult
Extremely High
Poor
N/A1
1.  As discussed previously, community feedback was limited.  Only one person attended the
public meeting held on the proposed plan. No opposition to the selected remedy was expressed.
Record of Decision
Port/and Cement Supcrfund Site
Operable Uait Three
P»gcNo. 47

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                                     Table 8-2
                      Summary of Remedial Alternative Costs
Treatment A Ittmoftve

1 . No Action
2. Natural Attentuation
3. Pump and Treat with
Co-precipitation
4. Pump and Treat with
Distillation
A
19GPM
B
27GPM
C
37OPM
NA
NA
X
X
X
X
X
X
Total
Capital
Cost
(1997$)
90,000
160,000
1,100,000
1,500,000
1,500,000
5,500,000
6,300,000
7,000,000
Total O&M
Presort Worth
Cost (100 yr,
i=*7X)
470,000
470,000
8,000,000
8,700,000
9,700,000
29,000,000
32,600,000
40,400,000
TotalCost*
(1997$)
560,000
630,000
9,100,000
10,200,000
11,200,000
34,600,000
36,100,000
47,400,000
1.  Costs accurate to within -30 to+50%
2.  No discount rate used to calculate costs
Record of Decision
Portland Cement Superfund Site
Operable Unit Three
Page No. 48

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9.0 MONITORED NATURAL ATTENUATION- THE SELECTED REMEDY

9.1 Designation of the Remedy

Based upon the results of the systematic screening process described above, UDEQ and EPA
agree that Alternative Two, Monitored Natural  Attenuation, most completely  satisfies  the
screening criteria and is designated as the selected remedy for OU3.  While all alternatives have
specific merits, only Alternative Two is both sufficiently protective of human health and the
environment and cost-effective.  Alternative Two has provisions which ensure attainment of all
four remedial action objectives:

   •  Institutional controls will prevent human exposure to Site ground water that would
    result in an excess cancer risk exceeding 1x10"*.
                                                      t
   •  Site  conditions  are adequate to  prevent  off-site  migration of contaminants  to
    uncontaminated  ground water and long-term monitoring will continue to ensure that no
    unacceptable off-site migration is occurring.

   •  Natural attenuation processes will restore the ground water to its natural background
    state and maximize its potential as a drinking water source. Long-term monitoring will
    ensure natural attenuation is achieving the expected results.

        The implementation  and  enforcement of ACLs  at  the ground water  discharge
    boundaries, as well as Site conditions,  will adequately protect surface water associated
    with the Site.

93 Implementation of the Remedy

The remedy will be implemented until such a time that the cleanup goals given in Table 6-5 and
discussed in Section 6.6 of this document are attained and all remedial action objectives are met.
Cleanup goals will be considered achieved when monitoring and statistical analysis indicates with
reasonable confidence that all portions of OU3 are  less than the cleanup goals. EPA expects in
excess of 100 years to be required to achieve these goals.

A suitable long-term monitoring plan will be developed subsequent to this Record of Decision and
will provide for statistically significant evidence as to  the state of contamination in the ground
water  and. the  migration  of contaminants to  unimpacted  areas  (both off-site  and  lower
uncontaminated aquifers), if any.

Numerous  safeguards will be implemented to  ensure  the remedy is continuing to provide
satisfactory protection of public health and the environment.   If monitoring indicates significant
off-site migration  of contamination is likely to occur or has occurred,  a review of the remedy will
Record of Decision                                                               Page No. 49
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be  conducted.   If monitoring at  discharge  boundaries indicates  that  ground water with
contaminants exceeding ACLs established for the protection of the City Drain (Table 6-3) is likely
to discharge or is discharging to  the  City  Drain, a review  of the remedy will  be conducted.
Monitoring will remain in effect until cleanup goals are achieved.  Surface water monitoring will
also be conducted  to ensure water quality standards established for the City  Drain are not
exceeded.  Institutional controls will remain in effect throughout the remediation period and as
appropriate after completion to prevent human exposure to ground water presenting unacceptable
health risks. Five-year reviews will also be conducted.

Because arsenic is the only identified  carcinogen, and its background concentration (64 ppm)
exceeds the health-based  1 x  10"6 cancer risk goal  established for a residential drinking water
scenario, it is recognized  that absent reductions in naturally  occurring background, this health-
based goal will not be met. Based on this and other natural water quality issues, it is understood
that any future use of ground water (even  after attainment  of remediation goals) for drinking
water purposes would require active treatment.
Record of Decision                                                                 Page No. 50
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10.0 STATUTORY DETERMINATIONS

The selected remedy must satisfy requirements of federal regulations set forth in the National
Contingency Plan (NCP), 40 CFR 300.430(f).  In accordance with these regulations the selected
alternative must:
                                                                                       0
   • Provide for the overall protection of human health and the environment and comply with
   ARARs (unless specific ARARs are waived).

   • Be cost effective; i.e., the costs are proportional to the overall effectiveness, where
   overall  effectiveness accounts for long-term effectiveness; reduction in toxicity, mobility,'
   and volume; and short-term effectiveness.
                                                     ?
   • Use to the maximum extent practicable permanent solutions employing treatment and/or
   resource recovery technologies.  The criterion is fulfilled  by selecting an alternative that
   provides the best balance of trade-offs of the five balancing criteria (overall protection of
   human  health and the environment; compliance with ARARs, short-term effectiveness;
   long-term effectiveness and permanence; and reduction in toxicity,  mobility, or volume)
   and considers preference for treatment as a principal element of the remediation with a
   bias against off-site land disposal of untreated waste.

EPA's Ground water Policy listed in the NCP preamble provides guidance on determining when
active remediation is necessary and the appropriate remediation timeframe for a particular ground
water classification:

   • EPA expects to return usable ground waters to their beneficial uses wherever practicable,
   within a time frame  that is reasonable given the particular circumstances of the site. (40
   CFR 300.430(a)(l)(iii)(F)).  For the most highly valued uses, such as drinking water, the
   most rapid remediation will be employed to the extent practicable.  Ground water that is
    naturally unusable because of characteristics such as high salinity may not be  actively
    remediated.

   • The minimum restoration timeframe will  be determined by hydrogeological conditions,
    specific contaminants at a site, and the size of the contaminant plume.  If there are readily
    available drinking water  sources  of sufficient quality  and yield that  may be  used  as
    alternative water supply, the necessity for  rapid restoration of the  contaminated ground
    water may be reduced.

   • More rapid restoration of ground water is favored in situations where future demand for
    drinking water is likely and other potential sources are not sufficient.  Rapid restoration
Record of Decision                                                                Page No. 51
Portland Cement Supcrfund Site
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   may also be appropriate where  the institutional controls to prevent the utilization of
   contaminated  ground  water for  drinking water purposes are not  clearly effective or
   reliable.  Institutional controls will usually be used as supplementary protective measures
   during implementation of ground water remedies.

   •  Natural attenuation is generally recommended when active restoration is not practicable,
   cost-effective,  or warranted because of site-specific conditions  (e.g. Class IIB  or m
   ground water which  is unlikely to be used in the foreseeable future or ground water
   plumes that are not expanding and/or impacting usable ground water and/or surface water
   resources).

Based on this  guidance  and the following key considerations  from the Detailed Analysis of
Alternatives (Section Seven),  both EPA and UDEQ agree that  Monitored Natural Attenuation
meets all statutory requirements in the NCP and CERCLA except  the preference for treatment:
                                                      i

   •   The selected  remedy will satisfy all  ARARs as well as provide a high  level of
   protectiveness for human health and the environment.

       Active  pump and treat  restoration is not cost-effective when compared to other
   alternatives.

   •   OU3  is not a current source of drinking water and, though classified by the State as
   Class HE,  is not likely to be a future drinking water source  due  to poor quality and the
   availability of alternate sources.

   •   Rapid ground water restoration is not mandated and is  not  practicable.  The most
   aggresive remedial alternatives involving extraction and treatment require in excess  of 100
   years to approach remediation goals. Other drinking water sources are readily available in
   sufficient quality and quantity,  and  institutional controls would  be implemented and
   enforced so  as  to  be  reliable  over the  long-term.    EPA  believes the  particular
   circumstances of the Site make  100+ years a reasonable time frame to achieve cleanup
   goals. UDEQ does not agree that 100+ years is a reasonable time frame, but agrees that
   there are no  technically practicable alternatives  that would  achieve cleanup goals in a
   lesser time frame.

       Natural physical processes such as flushing  and dilution will ultimately reduce the
   concentrations of contaminants  in groudwater  to levels that are reflective of natural,
   background conditions present at the Site.  Though background concentrations for some
    contaminants exceed drinking water standards and health-based goals, it is impracticable
    to attempt to remediate beyond these levels.
 Record of Decision                                                                 Page No. 52
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   •   Existing hydraulic barriers effectively contain the ground water contamination within
   Site boundaries and prevent the spread of contamination to unimpacted areas.  Both EPA
   and UDEQ agree that these barriers and conditions will be sufficient over the long-term.

   •   The establishment of ACLs, along with the Site hydraulics, adequately protect surface
   water associated with the Site.
Record of Decision                                                                Page No. S3
Portland Cement Superfoad Site
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/ L 0 EXPLANA TION OF SIGNIFICANT CHANGES

No significant differences exist between the Proposed Plan and this Record of Decision.
Record of Decision                                                             Page No. 54
Portland Cement Superfwd Site
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                APPENDIX A
         DETAILED ARARs ANALYSIS
(Appbcable or Relevant and Appropriate Requirements)

-------
                    POTENTIAL CHEMICAL SPECIFIC ARARS

                                       OU3

The  potential chemical-specific ARARs for the COCs at OU3 were developed using the
following sources:

             Safe Drinking Water Act MCLs (Title 40 CFR, Pan 141)
             Utah Primary and Secondary Drinking Water Standards (R309-103 U.A.Q
             Utah Ground Water Quality Protection Rules (R317-6 U.A.Q
             Utah Classifications of Waters of the State (R317-2 U.A.C)
             Utah Pollutant Discharge Elimination System Rules (R317-8 U.A.Q
             Clean Water Act - Water Quality Criteria (Title 40 CFR, Pan 131) and
             Corrective Action Clean-Up Standards Policy - UST and CERCLA Sites (R311-
             211 U.A.C)

Table 1 provides a summary of the chemical-specific ARARs which have been evaluated as
potential performance standards (or PRGs) for groundwater restoration.

SAFE PRINKING WATER ACT MCLs

The SDWA MCLs are the minimum state and federal standards for underground or aboveground
sources of public drinking water. The Utah Primary and Secondary MCLs axe found in U.A.C.
R309-103 and generally parallel the federal MCLs which are found in Title 40 CFR Pan 141.
The application of MCLs as ARARs for groundwater restoration is addressed in EPA guidance
(EPA,  1991c).  The guidance  states  that MCLs  are generally relevant and appropriate for
groundwater that is or may be used for drinking considering its use, value, and vulnerability.
 Neither EPA nor the  State of Utah has formally classified the Site groundwater; however, a
comparison of the EPA and State of Utah groundwater classification criteria, with the existing
background quality of the shallow HSU groundwater, indicates that the Site groundwater would
be classified as a potential drinking water source. The relationship between the federal and state
groundwater classifications, existing Site groundwater quality, and the application of federal and
state MCLs as ARARs for groundwater cleanup is described further in the following paragraphs.
      Groundwater Classification

 EPA's groundwater classification system establishes three categories for groundwater. Class I
 groundwaters are considered to be resources of unusually high value.  Class n groundwater
 includes all other groundwater which is currently (Class Ha) or potentially (Class Hb) a source
 of drinking water. Groundwaters which are not considered to be a potential source of drinking
 water are classified Class m.  Within EPA's classification system, the two factors considered
 in designating groundwater as Class n are: (1) water quality, and (2) yield. Water is considered
 to be suitable for drinking if it has a total dissolved solids (TDS) concentration  of less than

                                      A-l

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10,000 mg/1, and either can be used without first being treated, or can be rendered drinkable
after being treated by methods  reasonably  employed in.a public water supply system.  The
ground water quantity factor which defines a drinking water source is 150 gallons per day of
sustainable yield (Lavelie, 1997).

With a background IDS concentration of approximately 5,000 mg/1 (Dames & Moore, 1989a),
and a yield exceeding 150 gallons per day, the Site groundwater is consistent with an EPA Class
n classification.  Under EPA's  classification system, the groundwater would meet a Class nb
designation because background  groundwater quality  exceeds SDWA  MCLs  for  arsenic,
cadmium, and manganese, and  would require treatment prior to use as public drinking water.
Utah Groundwater Classification

The Utah Groundwater Quality Protection Rules found in R317-6 U.A.C, list the criteria for
groundwater classifications. Under these rules, Site groundwater would be classified as Class
m, Limited Use Groundwater,  to be protected as a potential source of drinking water, and as
a source of water for industry and agriculture.  Class m groundwater exhibits the following
characteristics:

       •     IDS greater than 3.000 mg/1 and less than 10,000 mg/1 (Site background TDS
             is approximately 5,000 mg/1), or;

       •     One or more contaminants exceed the ground water quality standards listed in
             Table 1 [of R317-6-2 U.A.C].  Table 1 of R317-6-2 U.A.C generally lists the
             SDWA MCLs as  the Groundwater Quality Standard.  In  the case of Site
             groundwater, background concentrations of arsenic and cadmium exceed  these
             standards.

MCLs as ARAR for Groundwater Restoration

The EPA guidance on the application of MCLs as ARAR indicates that "if the attainment of
a non-zero MCLG or MCL is impossible because the background level of the chemical is higher
than that of the MCLG or MCL, attainment of the MCLG or MCL would not be relevant and
appropriate."    Therefore, because background levels of arsenic, cadmium  and manganese
exceed their respective MCLs, the MCL is neither applicable  nor relevant and appropriate.
Conversely, the MCL  has been determined to be  relevant and appropriate for a COC whose
background concentration does not exceed its  respective MCL (as in the case of chromium).
                                          A-2

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                                        Table 1
          Summary of Potential Chemical Specific ARARs Evaluated As PRGs
                                    in Groundwater
                              Portland Cement Site:  OU3
Constituent of
Concern
Arsenic
Cadmium
Chromium
Lp«d
Manganese
Molybdenum
PH-
Federml
MCL
0.05
0.005
0.10
0.015"
None
None
6.5 - 8.5
State of Utah
MCL
0.05
0.005
0.10
0.015"
0.05
None
6.5 - 8.5
State of Utah
GW Quality
Standard
(R3 17-6-2)
0.05
0.005
0.10
0.015
None
None
6.5 - 8.5
State of Utah
Cleanup Standard -
Policy (R3I1-211)
0.064*
0.0062*
0.10
0.015
0.44*
0.182C
<8.0
Note:  Units in mg/f except for pH.
*      Standard is the background concentration (upper 95% confidence limit of the mean).
c
d
       Action level for lead at up.
       Standard is a health-based goal.
       Secondary MCL (SMCL).
UTAH GROUNDWATER QUALITY PROTECTION

The Utah Groundwater Quality Protection Rules are found in R317-6, U.A.C.  According to
section R3 17-6-6. 15 "Corrective Action," the gioundwater class protection levels should be
considered in this  ARARs analysis, but are  not intended  to be ARARs for federal or state
Superfund sites. However, the Utah " groundwater class protection levels" are separate and
distinct from the "groundwater quality standards."  Groundwater Quality Standards, numeric
pollutant limits listed at R3 17-6-2, U.A.C., are relevant and appropriate at this Site by operation
of R3 17-6-6.4,  which provides that discharges may never cause groundwater quality standards
to be exceeded*.  The Groundwater Quality Standards for the OU3 COCs are shown in Table
L
                                      5. UjLC. IM Ou Ua •/ AXAJti /onto Slu. DOUt
               t. km too met ktUfn thftati mtetutrj to toebtiU mi •* AMA* *W* Skt Itcmutt cOurAJUUtt. jy»f^tofly CriMMrf
        Wmtr QuMUrj StvUtrli. m JufUaatu gi»n On tlu^fttifle ctrrvmrumca. AffUeaiom of K31T-4-4.1S wontf Ounfm mm
        rmmlt In mmy 4\fftr*m rtuudltl mtaou er mudiul «<(w« g t*L Tk* 1/-S. EFA 4oa not mgrtt liuu Mt frovuio* to tffliftUt.
                                            A-3

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CORRECTIVE ACTION CLEAN-UP STANDARDS POLICY

Utah rale R3 1 1 -2 1 1 , " Corrective Action Clean-Up Standards Policy - UST and CERCLA Sites, "
establishes the federal MCLs  under the SDWA as the minimum standard for clean-up of
hazardous substances for water-related corrective actions. However, the rule further states **w

       "In the case  of contamination  above the MCL..., if after evaluation of all
       alternatives, it is determined that applicable minimum standards cannot reasonably
       be achieved, clean-up levels above these minimum standards may be established
       on a case-by-case basis  utilizing R31 1-21 1-3 and R3 11-211-4."

R311-211-3 presents the case-by-case evaluation criteria which are:

       •     The impact or potential impact of the contamination on the public health.
       •     The impact or potential impact of the contamination on the environment.
       •     Economic considerations and cost effectiveness of clean-up options.
       •     The technology available for use in clean-up.

R311-211-4 addresses prevention of further degradation of existing contamination levels in
water, soils, or air.   R311-211-5(c) states that:   "in assessing  the evaluation criteria, the
following factors shall be considered:                                .

       1.    Quantity of materials released.

       2.    Mobility, persistence, and toxicity of materials released.

       3.    Exposure pathways.

       4.    Extent of contamination and its relationship to present and potential surface
             and groundwater locations and uses.

       5.     Type and levels of background contamination.

       6.     Other relevant standards and factors as determined appropriate by the Board."

 CLEAN WATER ACT - USE DESIGNATIONS AND WATER QU           IT
 The Clean Water Act (CWA), Section 304, and Title 40 CFR Pan 131 require states to develop
 "Water Quality Criteria" and antidegradation criteria to protect the designated uses of surface
 water in  the state.  CERCLA  121(d) requires that CWA Water Quality Criteria be attained
 where relevant and appropriate.  These criteria and policies must protect aquatic life and human
 health, keeping the  stream's designated use in mind.  Human health standards include those
 established for drinking water and fish consumption as well  as fish consumption alone.

 The State of Utah water use designations and water quality criteria are codified in R3 17-2-6 and


                                           A-4

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2-14  U.A.C, respectively. To determine the appropriate chemical-specific limits for discharge
into a surface water body, it is necessary to determine how Utah has classified the designated
uses of the surface water body.   According  to R317-2-13.10 U.A.C,  drainage canals and
ditches  statewide are classified as "Class 6," unless specifically classified under R317-2-13
U.A.C.  The portion of Surplus Canal running past the Site is specifically listed under R317-2-
13.5 U.A.C and is classified 2B, 3B, 3D, and 4. Use classifications for waters of the state are
listed below:

       Class 1:      Protected for use as a raw water source for domestic water systems

       Class 1C:    Protected for domestic purposes with prior treatment by treatment
                    processes as required by the Utah Department of Health.

       Class 2:      Protected for in-stream recreational, use and aesthetics.

       Class 2A     Protected for primary contact recreation such as swimming.

       Class 2B:    Protected for secondary contact recreation such as boating, wading,  or
                    similar uses.

       Class 3:      Protected for in-stream use by aquatic wildlife.

       Class 3A:    Protected for cold water species of game fish and other cold water
                    aquatic life, including  the necessary  aquatic organisms in their food
                    ehain

       Class 3B:     Protected for warm water species of game  fish and  other warm water
                     aquatic life, including  the necessary  aquatic organisms in their food
                     chain.
                                                       %
       Class 3C:     Protected for nongame fish and other aquatic life, including the
                     necessary aquatic organisms in their food chain.

       Class 3D:     Protected for waterfowl, shore birds and other water-oriented wildlife
                     not included in Classes 3A, 3B, or 3C, including the necessary aquatic
                     organisms in their food chain.

        Class 4:      Protected for agricultural uses including irrigation of crops and stock
                     watering.

        Class 5:      The Great Salt Lake. Protected for primary and secondary contact
                     recreation, aquatic wildlife, and mineral extraction.

        Class 6:      Waters requiring protection when conventional uses as identified in
                     [Class 1 through 5] do not apply. Standards for this class are
                     determined based on environmental  and human health concerns.


                                            A-5

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The City Drain, because it was not specifically listed in R317-2-13.5 is assigned a default  use
designation of "Class 6". However, as discussed below, the Utah Department of Environmental
Quality, Division of Water Quality (UDEQ/DWQ) has established a site-specific classification
and numeric criteria for City Drain based on the environmental and human health concerns
posed by discharge of Site groundwater to City Drain.

Several meetings were held between DERR and the DWQ, both within the UDEQ, to establish
numeric  standards for parameters of concern for City Drain,  and to establish  a point of
compliance (POC).  This analysis is ordinarily conducted by DWQ as part of the water quality
permitting process, but because  this is a CERCLA action, only the substantive,  not the
administrative permit requirements are necessary.  Because the City Drain eventually discharges
to the Great Salt Lake, specifically the Farmington Bay Waterfowl Management Area, the DWQ
and DERR have classified City Drain as 3D.  Numerical levels were calculated for City Drain
based on the following factors:
                                                    *
       •     Protected uses and numeric criteria established for Class 3D;
       •     City Drain background surface water quality;
       •     City Drain flow rates;
       •     Groundwater discharge flow rate to City Drain;
       •     Proxicury, flow rates, and water quality of tributaries to City Drain.

.The performance standard defined by DWQ is that the in-stream concentrations at the POC will
not exceed 125% of the Class 3D water quality standards.  To establish numeric standards,
DWQ calculated the individual concentrations of contaminants in groundwater at the Site that,
if discharged to City Drain, would cause exceedance of the performance standard at the POC.
These numeric criteria are listed in Table 2.

                                       Table 2
     Concentration Limits for Groundwater Discharges from the She to City Drain
CJuitticol

Aluminum

Antmie
Cadmium
Cknmuum lit
Chromium VI
Cofftr
In*
CoHctiumuM (tit/1)

4S02J3

9.U2.U
139.0S
26.339.81
S69J6
1.564.5
25.S75.4t
Chtmical

Ltad

Mtrcury
Nteka
Stumium
SOrer
Zi*e

CtnetunuuM (tttfl)

666 71

0.63
20,667.94
251.75
6M
13.914.05

 The POC is in City Drain immediately downstream of the confluence of the City Drain and the
 north-south trending ditch (engine-block ditch) located on the west side of 1-215 (McNeal &
 MoeUmer, 1995 & 1997).  These site-specific numeric criteria are considered applicable for the
 OU3 remedial action.
                                           A-6

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Utah's antidegradation policy is found in R317-2-3 U.A.C. This rule states that nfi water quality
degradation is allowable which would interfere with or become injurious to existing instrcam
water uses. This section also affords protection to "High Quality Waters," categories 1 and 2.
Site-specific water quality criteria developed for the City Drain will not affect its "existing use."

Utah Pollutant Discharge Elimination System (UPDES) regulations are found in R317-8 U.A.C.
These regulations set standards for discharge of pollutants into surface water bodies in the State
of Utah, and for discharge of wastewater by land application. The regulations specify that for
toxic pollutants such as arsenic; cadmium, chromium, and lead, the Best Available Technology
economically achievable (BAT) must be  used to treat  the wastewater before discharge.  The
actual pollutant limits are developed on a case-by-case basis where there are no applicable
industry category standards.  Therefore, these levels would be negotiated with the State as pan
of the substantive requirements of a UPDES permit.  Effluent limitations for wastewater that is
land applied  are also calculated  (UAC  R317-8-2).    They  are  calculated by using effluent
guidelines, total concentrations in the waste stream,  amount of wastewater to be treated, and
the total wastewater flow.
                                             A-7

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                           LOCATION SPECIFIC ARARS

                                       OU3

Planned remedial activities for OU1 and OU2 involve excavation with off-site disposal of CKD
and underlying contaminated soils.  As a result, all existing surface features will be obliterated
and the post remediation surface will be entirely man-made.  It is expected that the remedy for
OUs 1 and 2 will be implemented before the OU3 remedy.  Because the new land surface will
not have any established animaJ or plant habitats, there will be no sensitive species "location-
specific" ARARs to review.  In addition, the Portland Cement site is not a seismically active
area.  Based on this information, no location-specific ARARs were reviewed for OU 3 activities.
                                           A-8

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                                      Action-Specific ARARj - Portland Cement Site: OUJ
Action
Remediation of
OftNHIOWftlCT
UiKharte of Water
into Suit «c* WilCT
Rodin
Treatment. Storage,
or Disposal in Waite
Pile
RCRA Standards fuf
Owners and
Operator* of
Hazardous Waste
Treatment, Storage M
Ditpoul Facililie*
Generation of
Hazardous Waste
TreatmcmVSlorafe in
Tank*




Rti|uirancflt

AN Mffccc wilcr ^ndivfa mud be in
compliant* with promulfittd UUh Pollutant
Dndiar|« Elimination System raki.

•
Must identify waste (hazardous or nan-
huudotn) Store correctly.
Ttnki cnort hive luffictenl ihetl Mfai(lh
(Ihiduien). and. for doted tanki. pream e
conlroh. to turne that they do not eolltpM
ormpruie.
Wule rmid not be jncomptlible with the
Unk material unfesi the tM* fa protected by

New Unki or component! mull be provideil
ivnh fccoiMttry conuiniiMnl.
Eliding tinki must instill ucondiry
conUimienl by ctrUin data, deptndin| on
ige. ifknown. Mort pipmg lyrtnm mml be
lite J with secondiry cdnlitnmenL
Finkj must be piovidtd with contrail to
prevent overfillmt; ind niffkienl frteboud
niinUined in open UnVi to prevent
overtopping by wave action or precipiUlion.
PrrrrojuiiHc

DiKtiirte orpolhitanti into Utah
lurfice wiler.
RC'R A haiudoui wutc lieiltd.
rimed, or diipotcd hi I wute pile
Oprrilion ol UtiUnenl. (tofagc nr
ditpoiil ftcililia for httirdain
watlei.
OenerilkMi of RCRA haurdout
waste
RCRA hazardoui wute (lilted or
ctunctrriilicX held in a tank for
Ireilment. stonge or dnpoial.
(40 CFR 26110)




CiUtion
«CFFlM.SubpulF
UACRJI3I6
40 CFR 171 and 11)
tlACl|7l
40 UR 164Subpu1 1
OACRJD-I 12
40 CKR Put 264. Subparli A II
HACR 113-1(1 I)
40 CFR 161. 161
UACR3I3-5
40 CFR 264 190
UACRJIM 10
40 CFR 164 191
UACR3I3-SIO
40 CFR 164. 191
UACRJI5-MO

40 CFR 164 194
UACRJI5MO
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR

ARAR
(rOnvncfiu
Requbrmenb are relevant and
appropriate Tor poundwater
monitoring.
Afiplicable
Applicible if wule pile if uied
Applicable fix v*i.

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Action-Specific ARARs-Poland Cement Site: OIJJ (Continued)
Action
Treatment/Slot age in
taiJu
(cool)



Container Slorag*





Requirement
Inspect the following overfilling control.
control equipment, monitoring data, vwle
level (for uncovered tanfci). 1** condition.
•dove-ground portion! oftanks. (to tttas
thtif (tract ural integrity) md the we*
(unuundini *K Unk (lo identify tifn of
leakage)
Repair any conosion. crad. or leak.
Al clonirc, remove all hazardoui wast* and
huwdmis wad* rtddiNt torn InA*,
dbcfurft control equipment *nd dbdiwfc
oonfiiH.Mitiil tfrucluvtt.
Store ignilible tnd reactive t»»Jle M u lo
prevent ttx wule from ifnilint or rrKlmf
IpiiuMe or metive wule* in cavered Unfci
mua con^ly with bufler tone reouirrnMnti
in 'Flunnuklc whl Combtmflrfe 1 jauidi
C>xk- Tiblet 2- 1 ihf ougb 2-6 (Ndiorul
F»e Piotedron AstocMiien. 1976 or 1911)
ConUinen oTKuardou* wule murt be:
• MainKined in good condition
• CompiliMe with huudoui wutc lo be
«orcd;«nd
• Cloicd
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Action-Specific ARARs - Poi.^nd Cemenl Site: OIU (Continued)
Action
Construction
Stale Cleanup Action
and Kiik Rased
Closure Standards fc»
USTsandCERCLA
titfi
Clean Clonirc far
Tanks, ConUinm,
•nd Wute Piles
Emergency Control*
Requirement
Fugitive dust control
• 1 lib requirement* k> be considered in
establishing cleanup standards for
groundwaler, turficc water, soils, «nd air.
• Requires cleanup foil of 1 x 1 0 ' risk

• Risk level of 1 « 10 ' fw carcinogens
tllewcd if *l>o htve iiMinitloMTcanlroli
ruch u monitorifli. deed noUtrwB, tfte
lecurity. He.
For wiler-ieliled coaectjve iction. MCI 4
ttUblitlKd unoW the SDWA tre tfie
minimum ituidcrdi lo be met (f it it
determined «flfr cvtluiliim tfiit tpplic«hle
minimum fltndinJf ctnrwt ft mmiNy be
•chievcd. clean-up levtli ihove tfieie
itandirdi may be erijblithed on a cue-by-
case bain
General closure performance ftandard for
Unkj and containers: mmonintron of need
for further maintenance and control;
minimization or elmmalkm of poit-cloiure
ocape of hajurdoiii waste. huiHoat
condittKiili. leachtle, conUminaled runoff,
or httifdoot wute decomnos rtion praducti
lo pound rutface water or atinoip<>eie.
Diipmal or decontamination of equipment,
Etructurcf and aoib.
Removal or decontamination of all wulc

conUmmaled lubsoilt, and itrvctum and
pojuiprnrnt contamntalco with wtuic and
earhate, and manajement of them u
uzirdoui waste.
Ensure cloiurt ii piotectivc of human health
Spill reporting.
Prerequisite
Generation of fugitive dust emiiiiora
Management of huardous waste or
hatardous conslrluenli thai exist in
environmental media.
RCKA hazardous waste (listed or
characteristic) management anil*.
n the event of • spill of hazardous
waste or material, which when spilled
becomo a hazardous waste.
Citation
IMO07-I2
liACRJII-211
40CFRZ64III;
IIACR1IM-7
IIACR 3131-113
40 CFR Hi III (general)
40 CFR 2641 71 (containers)
40 CFR 264 197 (tank.)
40 CFR 264.231 (waste pile)
UACR3I5I-99
IMCR3I5III J
40 CFR 264 III
UACRJ IS -1-7
DAC3IJ9
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR
ARAR
	 «,
INIVIHIIIa
Applicable
Applicable
Applicihle.
Applicable.
Applicable.
Applicable.

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       APPENDIXB
RESPONSIVENESS SUMMARY

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                                     APPENDIX B
                            RESPONSIVENESS SUMMARY
                    OPERABLE UNIT NUMBER 3: GROUNDWATER
                              PORTLAND CEMENT SITE

The following comments were submitted by Terry Sadler, Director of the Division of Environmental
Health, Salt Lake City & County Health Department in a letter to Mr. Bill Townsend, Project Manager
for the Division of Environmental Response and Remediation (DERR) of the Utah Department of
Environmental Quality (UDEQ) dated 28 January 1998. The letter is attached.

Comment 1:   Considering there is only a ten foot separation between the shallow hydfustialigraphic
unh (HSU) and the intermediate HSU, contaminaticm of this intermediale HSU is Kkdy. Has this been
taken *ntn account in regards to drinking water sources?

       Response:    The DERR and Region VIE EPA feel that contamination of the intermediate
       HSU is unlikely as Jong as the prevailing hydrogeologic conditions are not perturbed through
       natural or wan-induced causes.  The ciirrent site conditions that minimize the likelihood of
       downward migration of the shallow HSU contaminants are: J) a strong upward hydraulic
       gradient  (caused  by  confined conditions in  the intermediate HSU);  and,  2) the
       adsorptive/reactive capacity of the shallow HSU sediments.

       Contamination of the intermediate  HSU would likely occur if the vertical gradient were
       reversed Conditions that would reverse the gradient include a sustained period of flooding or
       high water in  the Surplus  Canal,  or extensive JocaUzed pumping of water from the
       intermediate HSU.  These exigencies were considered during the evaluation of remedial
       alternatives and support the decision by DERR and EPA to retrain  tram pumping
       groundwateraspart of an engineered remedy. Deed restrictions mat preclude future pumping
       of water from we shaUow or mtermediate HSUs are measures to ensure that contaminants
       from the shallow HSU do not migrate downward
Comment 2:  The Department would like more information on the health effects of allowing this
contaminated water to discharge to the surrounding surface water bodies. Has DEQ calre'ifltcd the
rate of discharge and Ekety contaminant levels? Have the effects on wfld&fe been evaluated?

       Response:    The contaminated water is currently discharging to the City Drain and the
       sanitary sewer that bisects the Site.  UDEQ, DERR and the Division of Water Quality (DWQ)
       have evaluated the rate of discharge and contaminant levels and concluded that there is no
       measurable degradation of the City Drain or the sanitary sewage leaving the Site. The details
       of these evaluations are presented in Appendix D of the Final Focused Feasibility Study
       (December 1997).

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       The effects on wildlife were evaluated as part of this process. The State of Utah water use
       designations and water quality criteria are codified in   R3 17-2-6 and 2-14   UJLC,
       respectively. DWQ established a site-specific classification and numeric criteria for City
       Drain based on the environmental and human health  concerns posed by discharge of Site
       groundwater to City Drain. Because the City Drain eventually discharges to the Great Salt
       Lake, specifically the Farmington Bay Waterfowl Management Area, the DWQ andDERR
       have classified City Drain as 3D.  Class 3D is set to protect waterfowl, shore birds and other
       water-oriented wildlife not included in Classes 3 A,  3B, or 3C, including the necessary
       aquatic organisms in' their food chain.

       Numerical levels were calculated for City-Drain based on the following Actors:

                     Protected uses and numeric criteria established for Class 3D;
                     City Drain background surface water quality;
                     City Drain flow rates;
                     Groundwater discharge flow rate to City Drain;
                     Proximity, flow rates, and water quality of tributaries to City Drain.

       The performance standard defined by DWQ is that the in-stream concentrations at the Point-
       of-Comph'ance (POQ will not exceed 125% of the Class 3D water quality standards.  To
       estahh'pfi pi/mppp ffafiffarff^ DWQ CSlcufotff? the individual fftnCfyitrPtfW* nffmntammimls fn
       groundwater at the Site that,  if discharged to City Drain, would cause exceedance of the
       performance standard at the POC. TbePOCis the confluence of City Drain with the drainage
       ditch on the west side of 1-215.
Comment 3 r  ID the preferred alternative, what is the length of tune gruundwBter FiMMMtcuu^g will be
conducted? The common is made that surface water monitoring wffl be **«»»«fc*^*ffd to ensure that City
Drain downstream users are protected. Wffl DEQ be performing this surface water monitoring and at
what frequency? In the event elevated levels are detected in City Dram, what protective measures wffl
betaken?

       Response:     It was intended that groundwater and surface water monitoring be conducted
       until remediation goals for groundwater have been achieved.  This duration is expected to
       exceed 100 years.  The details of the monitoring activities, such as sample location, sample
       frequency, analytes to be monitored, and corrective actions (if necessary), will be documented
       in a Groundwater Restoration Performance and Compliance Monitoring Plan to be completed
       as part of the Superfund Remedial Design and Remedial Action for OU3.  This plan will
       incorporate surface water monitoring as well.
Comment 4:  What is the expected time frame for natural attenuation to restore the site to acceptable
groundwater levels for Alternative 2?
Appendix B                                                                  11 March 1998
Responsiveness Summary                                                            Page B-2
Portland Cement Site OU3

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       Response:     The expected duration for groundwater restoration under Alternative 2 is in
       excess of 100 years.

Comment 5 :   In alternative's 3 and 4, the statement is made that this treatment would not involve
RQt A hamrriQjfg WSfo Later in the rinramvnf
a hazardous waste treatment facility would have to be met

       Response:     Under both Alternatives 3 and 4, the proposed treatment system would be
       treating groundwater that would meet the definition of a characteristic toxic hazardous waste
       as defined under Subtitle C ofRCRA (by virtue of arsenic concentrations exceeding 5mg/I).
       This necessitates that the groundwater treatment system be designed, under both alternatives,
       in accordance with certain RCRA requirements.  The distinction between the two alternatives
       is that treatment residuals (Le. sludges generated as a result of the treatment of groundwater)
       under Alternative 3 are expected to be RCRA hazardous waste, whereas the residuals under
       Alternative 4 are not  Therefore, RCRA locations! design prerequisites are not considered
       necessary for Alternative 4 facilities designed to store the treatment /»*»•*»»/«;

Comment 6:   How do you propose to enforce mstitun'onal cortrols?

       Response: Restrictions on future groundwater use will be noted on property deeds.  This
       notation is expected to be a sufficient deterrent to future development of groundwater
       resources. These restrictions may also be added to the Salt Lake Valley Water Resource
       Master Plan to preclude permitting of drinking water wells for OU3.

Comment 7 :   According to the document, in excess of 100  years vnSL  be required to naturaOy
attenuate groundwater to  acceptable levels. The costs under alternative 2  do not appear to indude
monitoring for such an extended period of time.  Has  the difference in monitoring costs between
alternatives 2,  3  and 4 been projected out over the  length of the  entire  project and factored for
inflation? Also, the costs «.gq»nv^ 00 unacceptable surface water impm'^s
       Response: Long-term monitoring costs have been included in all four alternatives and are
       calculated as the present worth assuming a duration of 100 years and an average rate of return
       of 7% including inflation.  These costs are documented in Appendix E of the Final Focused
       Feasibility Study for OU3, dated December 1997. Costs do not include the remediation of
       unacceptable surface water impacts because this is considered highly unlikely based on a
       rigorous modeling effort and calculations by the DWQ on the numeric criteria for City Drain.
Comment 8:   The statement is made that alternatives 3 and 4 would require over 100 years to
achieve remediation. Were pumping rates the limiting factor in this calculation? O*" pumping rates be
increased to achieve a faster cleanup? We would be interested in seeing the rationale for the choice of
the two pumping rates proposed.
Appendix B                                                                   11 March 1998
Responsiveness Summary                                                              Page B-3
Portland Cement Site OU3

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      Response: Limitations on the pumping rate for the shallow HSU is a major contributing factor
      to the long duration for groundwater restoration; however, the principal Actor affecting the
      duration of restoration is posed by the desorption kinetics for arsenic.  Under current off
      conditions, arsenic is strongly sorted onto shallow HSU sediments due to reaction with
      charged clay particles and adsorption to organic matter. In order to achieve groundwater
      restoration, the arsenic must be desorbed from the sediments.  The rate of desorption under
      current conditions is slow, thus prolonging the duration for restoration.  The modeling effort
      accomplished as part of the FFS incorporates the desorption kinetics for arsenic.

      The maximum pumping rate of 37gallons per minute is not arbitrary. This rate is a function
      of the shallow HSU hydraulic characteristics and represents an upper bound limit of me
      potential yield from wells or drams installed throughout Sites 2 and 3 and the West Site.
      Other lesser pumping rates were included in the FFS to compare to this maximum calculated
      pumping rate.   This comparison allowed  decision makers to evaluate the cost/benefit of
      lowering the remediation pumping rate below the maximum calculated rate.  Based on the
      groundwater modeling it  was determined that there  was no significant  difference in the
      predicted duration of restoration for the various pumping rates.  It was concluded then, that
      the duration of restoration is most sensitive to the desorption kinetics for arsenic.
Appendix B                                                                    11 March 1998
Responsiveness Summary                                                             Page B-4
Portland Cement Site OU3

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