PB99-964401
                              EPA541-R99-034
                              1999
EPA Superfund
      Record of Decision:
      Kennecott South Zone Site
      OUs 1,4, 5,10 & Portions of 11 & 17
      Copperton, UT
      11/3/1998

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     RECORD OF DECISION


KJENNECOTT SOUTH ZONE SITE
  Operable Units 1, 4, 5, 10, portions of 11, and 17
    Bingham Creek and Bingham Canyon Area

             November, 1998
     U. S. Environmental Protection Agency
          999 18th Street, Suite 500
          Denver, Colorado 80202

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                                L THE DECLARATION

  A.     SITE NAME AND LOCATION:

        This decision document covers all or portions of six (6) operable units which are part of
  the Kennecott South Zone Site proposed for inclusion on the National Priorities List  Included
  are Bingham Creek (Operable Unit 1), Large Bingham Reservoir (Operable Unit 4)
  Anaconda/ARCO/Copperton Tailings (Operable Unit 5), Copperton Soils (Operable Unit 10)
  portions of Bingham Canyon Historic Facilities (Operable Unit 11), and Bastian Sink (Operable
  Unit 17). The sites are located in unincorporated Salt Lake County, Utah, the City of West
 Jordan, and the City of South Jordan, Utah.

 B.     STATEMENT OF BASIS AND PURPOSE

        This decision document presents the selected remedial action (no action) for the Bingham
 Creek, Large Bingham Reservoir, Anaconda/ARCO/Copperton Tailings, Copperton Soils
 portions of Bingham Canyon Historic Facilities and Bastian Sink Operable Units of the Kennecott
 South Zone located in Salt Lake County, which was chosen in accordance with CERCLA, as
 amended by SARA, and, to the extent practicable, the National Oil and Hazardous Substances
 Pollution Contingency Plan (NCP). This decision is based on the administrative record for this
 site.

       The State of Utah concurs with the selected remedy.

 C.     DESCRIPTION OF THE RATIONALE FOR NO ACTION

       EPA has determined that no further action is required at these operable units  For
 Bingham Creek, Large Bingham Reservoir, and Anaconda/ARCO Copperton Tailings  previous
 response actions have eliminated the risks at these sites.  For Lower Bingham Creek Copperton
 Soils,  portions of Bingham Canyon Historic Facilities and Bastian Sink, no action is appropriate
 due to lack of risk for current and proposed land uses.

 D.     DECLARATION STATEMENT

       EPA has determined that no further action is required at these operable units in order to
 protect human health and the environment. Several cleanup actions were completed under
Removal authorities and these have eliminated the need to conduct additional remedial actions
Because, at some locations, wastes have been left in place, a five year review will be necessary

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 Max H. Dodson
 Assistant Regional Administrator
 Ecosystems Protection and Remediation
 U. S. Environmental Protection Agency, Region VHI
State Concurrence:
Dianne R. Nielson                                     rjate
Executive Director
Utah Department of Environmental Quality

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                              Q.  DECISION SUMMARY

A.     SITE NAME, LOCATION, AND DESCRIPTION
the Ken    nTT  T"' ^^ "" °f ^      ^ °f SiX (6) °P6rabIe UnitS which «« part of
 he Kenneco t South Zone Site proposed for inclusion on the National Priorities List Each of
these operable units are described individually.

       1 .     Bingham Creek (Operable Unit 1)

             a.      Bingham Creek Channel: The Bingham Creek Channel consists of the
             current and historic channel course of Bingham Creek from the Large Bingham
             Reservoir m the foothills of the Oquirrh Mountains on the west to the Brookside
             Mobile Home Park in the City of West Jordan on the east, a distance of about  13
             miles. The creek course at the Large Bingham Reservoir is located along the
             western side of unincorporated Salt Lake County near the town of Copperton,
             then travels easterly through the Cities of South Jordan and West Jordan.

                   The channel transects an eastward, gently-sloping alluvial plain that extends
            rrom the foot of the Oquirrh Mountains front to the Jordan River  The elevation
            ranges from 5300 feet (ASL) at the Large Bingham Reservoir to 4300 feet at the
            confluence of the creek with the Jordan River.

                   The upper part of the creek channel is located on private land used for
            farming, mining, and industrial purposes. Portions of the lower part of the creek
            channel are located on public lands used for open space and recreation but is
            bounded by suburban residential, commercial and industrial development  Other
            portions of the creek channel are located on privately owned residential property
            In some cases,  the creek has been rerouted in man-made ditches, channels and
            culverts with suburban development occurring on the historic channel.

                   Bingham Creek is an intermittent, losing stream that flows only during peak
            runofFpenods or during major storm events. The channel course  over time has
            meandered and overflowed during flood events that have been caused by natural
            and human-caused events. Historically, the creek has abandoned old channels and
            formed new channels spreading contaminated alluvial and waste materials across
            broad areas.  The principal aquifer under the creek is recharged along the foothills
            ot the Oquirrh Mountains and discharges downgradient at the Jordan River
            Groundwater (Operable Unit 2) is not being addressed in this decision document

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        b.     Bingham Creek Residential Soils

               The Bingham Creek Residential Soils area consists of certain residential
        development areas in the floodplain of Bingham Creek. Located in the cities of
        South Jordan and West Jordan, numerous residences were built on the floodplain
        or over historic channels.  Since most of the historic flow of the creek was diverted
        by early farmers and ranchers, some creek-borne contaminants were also found
        near irrigation ditches.  Neighborhoods affected include Jordan View Estates,
        Meadow Green, Fahnian  Ranchettes, Vista West, Sugar Factory, and Brooks'ide.
        Approximately 125 individual residences were addressed as part of three prior
        removal actions. Most of these residences were located within 2 blocks of the
        creek channel.

        c.     Lower Bingham Creek

              Lower Bingham Creek is the section of the creek between the Brookside
        Mobile Home Park on the west and the creek's confluence with the Jordan River
        on the east a distance of about a mile.  This section is located in the historic Jordan
        River floodplain and is relatively flat. The creek courses through industrial and
        agricultural lands here.  On the west, the creek is buried in a culvert underneath a
        light industrial park with associated parking lots.  From the industrial park on 1300
       W. the creek flows through agricultural and ranch land to an asphalt plant.  The
       land  between the asphalt plant and the Jordan River is used for agriculture
       (currently, alfalfa).  The creek in this section is a man-made ditch.  The nearest
       residences are about 2 blocks away. There is a small flow in the creek through this
       section originating with some springs at the Brookside Mobile Home Park and
       overflows from an irrigation canal near the Jordan River.  There is a Brownfields
       proposal to use a portion of this land as a recreational corridor with bike paths and
       trails.

2.      Large Bingham Reservoir (Operable Unit 4)

              The Large Bingham Reservoir is located just to the south of the town of
       Copperton at the mouth of Bingham Canyon in the Bingham Creek channel  It
       was built in 1965 by Kennecott Utah Copper Corp. (hereinafter referred to as
       Kennecott) to impound Bingham Creek waters and leachate waters from
       Kennecott mining operations for recovery of metals and industrial process water.
       The original reservoir was unlined and, located in the recharge area for the
       principal aquifer, it has been shown to be a major source of groundwater
       contamination.

             The old reservoir was retired and a new one replaced it. The new reservoir
       is lined and is also used for storage of stormwater and process water by Kennecott.

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         The land use is industrial/mining. The nearest residential community is Copperton,
         about K mile to the north. The area is fenced and is not accessible to the general
         public.                            -

  3.      Anaconda Tailings (Operable Unit 5)

         a.     Anaconda Tailings

               The Anaconda Tailings, also known as Anaconda (ARCO) Tailings
        Copperton Tailings, ARCO Copperton Tailings and Utah-Apex Tailings consists
        of approximately 3.5 million tons of lead, arsenic, zinc, and silver-bearing fine-
        grained sediments covering 41 acres along the south side of Bingham Creek in the
        north one-half of Section 16, Township 3 South, Range 2 West It is located
        adjacent to Bingham Creek. Erosion, seepage and tailwaters from the tailings
        created contamination along Bingham Creek, Bastian Ditch, and into Bastian Sink
        and near-by agricultural lands.  The land use is industrial/mining and since
        remediation occurred, is used for open space. The nearest residential
        neighborhood is Copperton, about 3/4 mile away. The site is fenced and is not
        accessible to the general public.

        b.     Bastian Ditch

              The Bastian Ditch had its origins in the 1880's when water was diverted
        from Bingham Creek near the Oquirrh foothills to the Bastian Sink vicinity  The
        ditch earned water as far south as Copper Creek. The Ditch originates in the
        vicinity of the Anaconda Tailings and roughly follows Utah Highway 111
        southward. It was used by farmers to convey water from Bingham Creek and later
        the Anaconda Tailings Impoundment to their fields. A recent study of aerial
        photographs indicates the ditch system continued southward nearly to Butterfield
        Creek. Subsequent sampling showed scattered elevated lead values in the southern
        extension of the ditch system.  The current land use is industrial and agricultural
        The nearest residential neighborhood is Copperton, 3/4 mile away (at northern end
       ot the ditch).  The ditch, where it exists, is not in use.

4.     Copperton Soils (Operable Unit 10)

       The town of Copperton is located at the mouth of Bingham Canyon adjacent to
Bingham Creek on the south side of town. The eastern end of the town was built on  an
historic tailings deposit, particularly the residences along Copperton Circle   The land use
is residential.  Lands just to the east of Copperton Circle are industrial/mining land use

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5.
        Portions of Bingham Canyon Historic Facilities (Operable Unit 1 1)
        Bingham Canyon is located on the east flank of the Oquirrh Mountains. Mining of
 mineral resources in Bingham Canyon and it tributaries began in 1 863.  Open pit mining of
 copper ores began in 1903 on the headwaters of the canyon. Today, Bingham Canyon
 Mine open pit is about 2 Yz miles across and over '/2 mile deep and is surrounded on the
 east, south, and north sides by waste rock dumps.  Older mining and milling facilities
 which have been documented in historic literature have been buried by the waste rock
 dumps or mined away by nearly 100 years of open pit operations.

        The area where most  of the historic mining operations existed is still occupied by
 an active mining operation and is zoned industrial/mining. Activities include mineral
 exploration, blasting in the pit, hauling of ores and waste rock by trucks and rail, and
 maintenance of the facilities.  A visitor center is located near the top edge of the'pit, but
 the access is through the Lark Gate. Kennecott owns all the water rights in the watershed
 (including stormwater runoff, snow melt and leach waters) and uses  them for industrial
 processing. The mine is fenced and is not accessible by the general public. The nearest
 residences to the Bingham Canyon Mine are located in the town of Copperton adjacent to
 the Bingham Canyon Gate. Current operational facilities, including,  but not limited to, the
 Bingham Canyon Mine, the Bingham Canyon Mine Waste Rock Dumps, the Kennecott
 Precipitation Plant, and the Copperton Yards are not included in this decision document.
 The footprint of the former Proler operation is not included. Groundwater issues
 associated with the mine are also not included in this decision document.

 6.     Bastian Sink (Operable Unit 17)

       The Bastian Sink is  located in the south central portion of Section  15 and the north
 central portion of Section 22,  Township 3 South, Range 2 West. It measures 3,000 feet
 by  1,200 feet at its maximum extremities, totaling approximately 60 acres. It is'a
 topographic low just to the south and east of the Trans Jordan Landfill on  State Highway
 111. Bastian Sink  received waters diverted from Bingham Creek and the Anaconda
 Tailings Pond via the Bastian Ditch. The water was used to irrigate farmland in the area.
 The water flowing  in the Ditch contained considerable tailings sediments probably derived
 from flow through  the tailings pond.

       The current land use is agricultural, but has been zoned for industrial land use.
The nearest residence is in Copperton,  approximately 2.5 miles to the west. The area is
fenced and is not accessible to the general public.

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B.     SITE HISTORY AND ENFORCEMENT ACTIVITIES

       1.     Bingham Creek (Operable Unit 1)   —

             The Bingham Creek Channel is located downstream from the West Mountain
      (Bingham) Mining District on the east flank of the Oquirrh Mountains where mining
      activities began in 1863.  Bingham Creek originates in Bingham Canyon within the
      borders of the mining district and trends easterly to the Jordan River. The distance of
      Bingham Creek from the Large Bingham Reservoir, located near the mouth of Bingham
      Canyon, to the Jordan River is about 13 miles. During the early  days of mining wastes
      from mining and mineral processing (mine dumps, mill tailings, and smelter slag) were
      dumped directly into Bingham Creek or stored adjacent to the creek where they were
      subject to erosion and transport to the creek. The mining wastes contained elevated levels
      of lead, arsenic, and other heavy metals. Over the years, especially during flood events
      these mining and processing wastes washed downstream where they were deposited in the
      creek channels and floodpiain. The land through which Bingham Creek trends was
      onginally farm land, but with the growth of the Salt Lake City suburbs, several residential
      neighborhoods were built along the creek, on floodplains, and over historical creek
      channels.

            Three removal actions in accordance with Action Memoranda dated May 1991
      January 1993, and June  1995,  were performed by EPA, ARCO and Kennecott to address
      the problems associated with mining wastes in the channel of Bingham Creek and in the
      neighborhoods built on the Bingham Creek floodpiain.

            a.     Bingham Creek Channel

                  On February 18, 1993, EPA issued a Unilateral Administrative Order
            (UAO) for Bmgham Creek Phase II to ARCO (Atlantic Richfield Company) and
            Kennecott, Docket No. CERCLA-VHI-93-10. This addressed the contaminated
            tailings removal in the Bingham Creek channel as outlined in the Action
            Memorandum dated January 28,  1993. Lead values up to  30 000 mg/kg were
            found. The removal extended from the Kennecott Large Bingham Reservoir dam
            to the downstream side of the Brookside Trailer Park, a channel distance of
            approximately nine miles.  The work was conducted by ARCO and Kennecott
            under the supervision of EPA and UDEQ.  In general, wastes in the creek channel
            containing over 2,000 mg/kg lead were removed down to three feet or deeper any
            remaining contamination was capped, and the creek bed was then recontoured
           The excavated wastes were hauled either to the Kennecott Bluewater Repository
           or to the Anaconda Tailings.

                  In the process of cleaning up the creek channel, a number of road crossings
           and utility corridors were encountered and cleaned up: West Valley Highway

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 Crossing, Kern River Gas Transmission Co Pipeline Crossing (under provisions of
 Administrative Order on Consent, CERCLA VIII 92-01), 3200 West Street
 Crossing, and Salt Lake County Water Conservancy District Water Pipeline
 Crossing.  A number of historic facilities and waste storage locations were also
 encountered and cleaned up: Tailwater Ditches, Bingham Flats, Evaporation Ponds
 Canals, Cemetery Pond, Mixed Tails; Robbe Cells, McGregor Precipitation Plant,

 New York and Utah Mill,  Revere Smelter, Holy Cross Hospital Grounds [now
 Paracelsus Jordan Valley Hospital], and the Redwood Road Pond.

       The Cities of West Jordan and South Jordan have agreed to supervise long
 term management of the site using existing authorities for land use planning,
 zoning, and building permits.

 b.     Bingham Creek Residential Soils:

       During Bingham Creek Phase I, in 1991, surface soils contaminated with
 mining wastes were excavated and removed from 50 residential properties in West
 Jordan which were located within the historic flood  plain of Bingham Creek in
 accordance with the Action  Memorandum dated May 1991. Lead values up to
 12,000 mg/kg were found in the soils. Soils with lead concentrations exceeding
 2,500 mg/kg were removed  and replaced with clean fill.   EPA conducted the
 removal in conjunction with Kennecott.  Kennecott participated by constructing a
 mine waste repository (Bluewater Repository)  and providing hauling services
 from the site to the repository. Their participation was done under the provisions
 of an Administrative Order  On Consent, Docket No. CERCLA-VT.II-91-11, dated
 May 20, 1991. Kennecott also paid EPA a portion of the costs associated with
 this action.

       Bingham Creek Phase III occurred in  1995-1997 and addressed 75
 residential properties in accordance with the Action Memorandum dated June
 1995.  It provided for the removal of soils which had concentrations in the soil
 exceeding 1,100 mg/kg lead and/or 100 mg/kg arsenic.  Removal depths in both
 actions were as much as 18 inches which was then replaced with clean soil. The
 removal took place in areas which were determined to provide a pathway for
 exposure to residents. In Phase III, the work was conducted by ARCO under the
 provisions of Unilateral Order CERCLA VIH-95-19 dated July 21, 1995, and
amended October 31, 1995.   The work was conducted under supervision of EPA
and UDEQ.  The contaminated materials were hauled to the Anaconda Tailings.

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         t^rm       CitiCS °^6St J°rdan and South Jordan have a§reed to perform lone
         term management of the site using existing authorities for land use planning
         zoning, and building permits,       ...                               °'
         c.      Lower Bingham Creek
                              mining wastes washed all the way from Bingham Canyon
                              5EQ  Kennecott, and EPA have all confirmed that elevated
                              nd alon8the creek channel.  This area located in the
         Jordan River floodplain, is used for agriculture, ranching, and industry  There are
         no plans to develop this area for residential use.  Therefore, the data^onceSn"
         he location of rmmng waste contamination were transferred to the City of West
         Jordan who w,ll manage this area in the future through land use planning, zoning
         and budding perrmt authorities. The city has received a Brownfields Grant to
         design a long-term plan for this and nearby areas.                 swam to

  2.     Large Bingham Reservoir (Operable Unit 4)


  the tn JT f9r 5' KenneCOtVconstructed a. reservoir on Bingham Creek just to the south of
  Bin
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        Adjacent to the Large Bingham Reservoir to the north is the Small Bingham
 Reservoir. The original Small Bingham Reservoir was also constructed in 1965 as a mine
 waste treatment facility and a sewage lagoon for the town of Copperton  The original
 reservoir was lined with clay.  In 1990, Kennecott took the reservoir out of service
 excavated some of the materials, and installed a new reservoir equipped with clay  '
 geotextile, and HOPE liners with a leak detection system. The performance of this
 reservoir is monitored through a Utah  Groundwater Permit (UGW 350004).

       EPA and Kennecott entered into Administrative Order on Consent CERCLA VIII
 92-10 on June 23, 1992 under which Kennecott performed the removal action at the Large
Bingham Reservoir.                                                            &


3.      Anaconda Tailings (Operable Unit 5)

       a.     Anaconda Tailings Impoundment

             The Anaconda Tailings is located immediately south of Bingham Creek
      near the Kennecott Large Bingham Reservoir. The Tailings Site was originally a
      tailings pond constructed in  1914 to trap the tailings produced by the Utah Apex
      and,Bingham New Haven Mills upstream in Bingham Canyon. Tailings were
      sluiced to the site via flumes. The pond allowed most of the tailings to settle out
      The water,  containing acids, heavy metals, and residual tailings, was then sent back
      to Bingham Creek or used by farmers for irrigation.

             EPA issued a Unilateral Administrative Order (CERCLA VIII 93-06) with
      an effective date of January 25,  1993, to ARCO requiring  ARCO to conduct an
      Engineering Evaluation/Cost Analysis (EE/CA) and complete a removal action at
      the Anaconda Tailings  Site.

             The Anaconda Tailings Removal Action, which occurred  from  1993 to
      1997, consolidated the  lead tailings from a 96-acre parcel to the western end of the
      site where they were capped  with a HDPE liner, clay, and soils.  Also included in
      the capped area were the soils excavated from ARCO projects along Bingham
      Creek during Phases II  and HI. Run-off and run-on controls were installed to
      prevent water from entering the site, and to prevent erosion of the cap into
      Bingham Creek during storm events. The facility was designed to withstand a
      100-year storm event.

            ARCO has agreed to perform long-term maintenance of the capped
      repository. In addition, Salt Lake County has agreed to use its authorities in land
      use planning, zoning, and building permits to insure that the cap integrity is not
      compromised.
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         b.      Bastian Ditch

                The Bastian Ditch was constructed in the 1880's to convey irrigation
         waters from Bingham Creek to ranch and farm land south of the creek  The ditch
         captured tailings that entered the creek upstream of the diversion.  When Utah
         Apex constructed their tailings impoundment in 1914, the farmers also used the
         tailwaters for .rngation.  Historical records indicate that the tailwaters were not
         free of contamination. Remnants of the ditch could be seen along the south side of
         the Anaconda Tailings and on Kennecott lands south of the Anaconda Tailings.

               The tailings deposited in the Bastian Ditch were removed by Kennecott and
         ARCO on their respective lands. ARCO placed these tailings in the main ARCO
         tailings capped repository.  Kennecott hauled the tailings from their sections of the
         ditch to the Bluewater Repository.

               ARCO performed its cleanup of the Bastian Ditch under the provisions of
        Unilateral Administrative Order CERCLA VIII 93-06.  Kennecott performed its
        cleanup  under the provisions of Administrative Order on Consent  CERCLA VIE
        98-09 under which Kennecott agreed to perform response  actions at several areas
        including a  portion of the Bastian Ditch.

 4.      Copperton Soils (Operable Unit 10)

        Historical photographs reveal that the eastern end of the town of Copperton was
 built on a tailings deposit. The tailings may have come from the experimental Utah
 Copper mill built in 1903, but this is not known for certain. EPA investigated the area in
 1994, and determined that this section of town had, in fact, been built on mine wastes but
 the concentrations of hazardous substances were low and well beneath action levels for
 residential property. EPA determined that no action was required.
 5.
Bingham Canyon Historic Facilities (Operable Unit 11)
       Mineral resources were discovered in Bingham Canyon in 1863.  It was not long
before the canyon and its tributaries were covered with small mining milling  and
processing operations.  The ores near the surface contained gold, silver, lead  zinc  and
copper. A wide variety of mineral processing techniques were used by the mills depending
on the requirements of the specific ore. Typically, wastes were simply dumped directly
into the creek or impounded along the banks of the creek.

       In 1903, Utah Copper began open pit operations in the Canyon and bought the
mining claims as their pit operations grew. Today, most, but not all, of these  historic sites
                                       11

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 have been subsumed by the pit itself or buried under the Bingham Canyon Mine waste
 rock dumps.

        In 1993, EPA began compiling a list of the facilities known to have operated in the
 canyon. In 1995, Kennecott began to characterize the sites by describing the locations
 what was known about the operations there,' and where their wastes were located  If the
 site was accessible (not buried by waste rock or subsumed by the pit), Kennecott collected
 samples to determine what hazardous substances were left by these operations. This
 activity was performed under the provisions of the Kennecott/EPA/UDEQ  Memorandum
 of Understanding signed in September, 1995.  The results of the characterization of
 historic facilities are in three reports called On-Site Environmental Assessments. EPA and
 UDEQ used the results of this study to determine if cleanups were needed.

       EPA and UDEQ concluded that each facility in Bingham Canyon fell into one of
 several broad categories: (1) facilities whose footprints no longer exist because they have
 been mined away by the growing Bingham Pit; (2) facilities whose footprints have been
 buned by waste rock from the Bingham Mine or have been buried underneath a current
 operating facility; (3) facilities which could be characterized but any contamination found
 was consistent with the current land use and did not require cleanup; (4) facilities which
 were characterized and required  cleanup; (5) facilities which were found not to have
 operated and therefore produced no wastes; (6) facilities which were located in areas
 which were cleaned up during CERCLA and non-CERCLA cleanups' and (7) current
 facilities.

       Facilities whose footprints no longer exist because they have been mined away as
the pit grew are:

       Utah Apex Mill
       Rogers Mill #1  and #2
       Boston Consolidated Mill
       Stewart #2 Mill
       Columbia Copper Mill
      Jordan Mill
       Spanish Mill
      Telegraph Mill
      Silver Shield Mill
      Bingham Gold
      Utah Concentrator
      Utah Mill
      Brooks Mill
      Durrant Mill
      Eagan and Bates Mill
      What Cheer Mill
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       Murphy Mill
       Boston Launder (exact location unknown)
       Apex Yard Launder
       Ohio Copper Launder
       Copper Center Gulch Launder
       Main Canyon Launder (exact location unknown)
       A Pit Launder (exact location unknown)
       Drain Tunnel Launder (exact location unknown)
       Ingersoll Gulch Launder
       Starless Launder
       Copper Placer Launder
       Utah Smelter
       Winnamuck Smelter

       Several of the historic sites were buried by the Bingham Mine Waste Rock Dumps
or current facilities.  At these sites, any wastes left by these operations were buried and  no
longer accessible for sampling or remediation:

       Lead Mine Mill
       Utah Copper Mill
       Winnamuck Mill
       Markham Mill
       Walls Mill
       Shawmut Mill
      Highland Boy Mill
      Bingham-New Haven Copper and Gold Mill
      Last Chance Mill
      New England Gold and Copper Mill
      Stewart Mill
      Bemis Mill
      West Mountain Mining Co. Mil!
      Bingham Mining and Milling
      Utah Consolidated Gold Mill
      Heaston Concentrator Jigs
      Massasoit Mill
      Bingham New England Mill
      Tiewaukee Dump Launder
      McGuires Gulch Launder
      Galena Gulch Launder
      Winnamuck Precipitation Plant
     Cuprum Yard Plant
                                     13

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         Watsons Jig
         Darrenugue Jig (mobile facility)
         Verona Uranium                   -

         The footprint of a few sites was available for characterization, but the
 concentrations of hazardous substances were sufficiently low to present little threat at
 their land use. These sites included:

        Copperton Dumps
        Yampa Smelter

        In one case,  a facility was found that needed cleanup. This facility, operated by
 Proier to process cans for use in precipitation plants, has not been fully cleaned up and is
 therefore excluded from this decision document.

        One site, the Zinc Concentrator, was investigated and no wastes were found at the
 site.  It was later learned that the mill facility had been built but never operated.

        Several facilities on the comprehensive facility list were cleaned up as a part of the
 Bingham Creek Channel cleanup or decommissioned by the Utah Division of Radiation
 Control. The facilities required no further action. These facilities were:

       Robbe Cells
       McGregor Plant
       New York and  Utah Mill
       Revere Smelter
       Mixed Tailings
       Yellow Cake Plant
       Although the mining and ore processing facilities which are still currently active
may have hazardous substances at their locations, these were not systematically
characterized and are therefore excluded from this decision document. This category
includes, but is not limited to, the following facilities in Bingham Canyon:

       Bingham Canyon Open Pit Mine
       Bingham Canyon Mine Waste Rock Dumps
       Barneys Canyon Gold Mine
       Copperton Concentrator
       Kennecott Precipitation Plant
       Truck and rail maintenance shops
       Dry Fork Electrowining facility
       East-side Collection  System
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         Dry Fork Collection System
         Bingham Canyon Collection System

         Information about the status of each of these historic facilities has been forwarded
  to Salt Lake County who has  agreed to use its land use planning, zoning, and building
  permit authorities to manage the Bingham Canyon historic sites area in the future.

  6.     Bastian Sink (Operable Unit 17)

        The Bastian Sink contains elevated levels of lead and arsenic due to receiving
  irrigation waters from Bingham Creek and tail waters from the Anaconda Tailings  Water
  was conveyed to the area by the Bastian Ditch. There are estimates of 800,000 cubic
  yards of lead and arsenic contaminated sediments in the Bastian Sink area  This area was
  characterized by ARCO under the provisions of the Unilateral Administrative Order for
  Anaconda Tailings.  Approximately 22% of the area was found to have elevated lead and
  arsenic above residential action levels.

        Because the current land use of this area is agriculture, and the zoning is industrial
 the lead and arsenic do not pose a significant current risk.  There are no future plans to
 develop this site for residential purposes. The City of South Jordan has agreed to provide
 long term management of the site using its land use planning, zoning, and building permit
 authorities.
 C.     HIGHLIGHTS OF COMMUNITY PARTICIPATION

       The Administrative Record original documents are housed in the EPA Region VHI
 Superfund Records Center, and an information repository is available at UDEQ. EPA and
 UDEQ also established and maintained a local information repository. Originally the
 repository was at the West Jordan Library until it exceeded the storage capacity of the
 library. Then it was relocated to West Jordan City Hall.

       A site-wide community relations plan was completed in 1991 by UDEQ.

       Residents were kept informed via public meetings, neighborhood meetings
individual meetings with impacted homeowners, availability sessions where the residents
could receive information concerning blood leads and soil concentrations  letters and fact
sheets. In addition EPA and UDEQ responded to requests for information on real estate
and other related issues via phone, fax, and mail.  The proposed plan indicating EPA's and
UDEQ's preferred approach for this area was mailed to all residents impacted by the
various actions, as well as public officials, and the media.
                                        15

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         EPA and UDEQ worked closely with the Cities of West Jordan and South Jordan
  and Salt Lake County to develop protocols for long-term protection of the remedies using
  existing local ordinances covering land use planning, zoning, and building permits
  Alternative approaches were discussed and documented.

         EPA  and UDEQ established a site wide Risk Assessment Task Force to provide a
  forum by which national and local experts could discuss risk assessment issues and
  propose studies to resolve the issues.  Citizens of Bingham Creek neighborhoods
  contributed home grown vegetables to aid in these studies.  One farmer participated in a
  study of the uptake of lead and arsenic in wheat grains. Prior to setting a final action level
  for residential properties, affected residents were invited to a meeting to discuss several
  issues, including land use and uncertainties in risk calculations.  Several approaches were
  proposed by EPA and UDEQ. The property owners evaluated their options and indicated
  which approach they preferred. The final action level for residential properties
  incorporated their recommendations.

        EPA and UDEQ briefed city, county,  state legislative, and congressional officials
 as requested.

        A public meeting regarding the Proposed Plan with EPA's and UDEQ's preferred
 alternative (No further action) was held on May 13,  1998, at West Jordan City Hall  A
 responsiveness summary to the comments received is provided in Section III.


 D.     SCOPE AND ROLE OF OPERABLE UNIT WITHIN SITE STRATEGY

       The Kennecott South Zone Site, proposed for the National Priorities List is
 composed of  approximately 13 Operable Units which encompass geographical areas or
 med.a-spec.fic issues.  This Record of Decision covers 6 Operable Units (or portions
 thereof) within the Kennecott South Zone Site.

       1.  Bingham Creek (Operable Unit 1) includes surface soil contamination within
 the channel and flood plain of Bingham Creek;

       2. Large Bingham Reservoir (Operable Unit 4) includes the Large Bingham
 Reservoir and  Small Bingham Reservoir located at the mouth of Bingham Canyon;

       3. Anaconda Tailings (Operable Unit 5) includes the surface and near surface
contamination  from an historic tailings impoundment  of Utah Apex Mill, located upstream
in Bingham Canyon and the Bastian Ditch;

      4. Copperton Soils (Operable Unit 10) which includes surface soil contamination
on the east side of the community of Copperton;
                                       16

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        5. Bingham Canyon Historic Facilities (Operable Unit 11) which includes historic
  milling and smelting facilities located in Bingham Canyon; and

        6. Bastian Sink (Operable Unit 17) includes the Bastian Sink  which received
  tailwaters from the Anaconda Tailings Site. ,


        Groundwater underneath these areas (Operable Unit 2) will be addressed in a
  separate action.  Surface contamination, surface impoundments, and other waste piles at
  other geographical locations in the Kennecott South Zone have been addressed in separate
  actions, including, for example, Butterfield Canyon, Lark, and the South Jordan
  Evaporation Ponds.

        Also not addressed in this Record of Decision are current mining facilities
  including, but not limited to, the Bingham Mine, the Bingham Mine Waste Rock Dumps
 (Eastside, Westside, Dry Forks, etc.), Copperton Precipitation Plant, Copperton
 Concentrator, and current truck and rail facilities.

        The Denver and Rio Grande/Southern Pacific/Union Pacific railroad right of way
 between Midvale and Bingham Canyon is specifically excluded from this decision
 document. A separate action may be needed, particularly if this  line  is  abandoned.

        The former Proler facility located to the east of the Copperton Cemetery on  the
 banks of Bingham Creek channel is also excluded from this decision  document. A
 separate action may be needed at this site.

        The selected remedy for the Bingham Creek and Canyon facilities (OUs 1, 4, 5,  10
 11, and 17 or portions thereof) of the overall Kennecott South Zone is "no further'
 action" because the risks to human health and the environment have been eliminated
 through previous removal actions, land use/building permit controls,  and/or the wastes are
 inaccessible and do not pose a risk to human health or the environment.

 E.     SITE CHARACTERISTICS

 1.     Known or suspected sources:

       Bingham Creek originates in the Oquirrh Mountains where mineral resources were
discovered in 1863.  At first, the minerals were retrieved by digging underground shafts
and tunnels.  Later, open pit mining techniques were developed and used. The waste rock
generated from the sinking of the tunnels or open pit excavations was disposed of near the
portal or edge of each mine.  Although some mining companies shipped their ores outside
the canyon for further processing, others built mineral processing facilities near their
mines.  Wastes from the processing, mill tailings and smelter slag were disposed of into
                                        17

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the creek itself where they were washed downstream.  Wastes were also placed in piles or
impoundments along the banks of the creek where they, too, were subject to erosion and
redeposition downstream.  Because of the small particle sizes, mill tailings were
particularly prone to erosion and movement downstream.
       a.
Mills
       The following table gives details about the mills which were known to have
operated in Bingham Canyon or its tributaries:
                   HISTORIC MILLS IN BINGHAM CANYON
Name
Lead Mine
Mill
Utah Copper
Company
Mill
Winnamuck
Mill
Markham
Mill
Walls Mill
Shawmut
Mill
Years of
Operation
1882-1896
1904-1910
1877-1913
1893-1917
1874-1911
1900-1902,
1906-1907
Processes
Used
grinding,
smelting
grinding,
gravity
separation
grinding,
gravity
separation,
cyanide
leaching
Milling
Grinding,
gravity
separation
Grinding,
gravity
separation
Ore
Processed
Pb/Au/Ag
Cu
Pb/Au/Ag
Pb
Pb/Ag/Au
Pb/Ag/Au
Volume of
Wastes
produced*
46,667 tons
1 .4 million
tons
122, 500 tons
76,000 tons
11 6,667 tons
8333 tons
Current
Status
Buried by
current
Kennecott
Precipitation
Plant
Partially
buried by
waste rock
Buried by
waste rock
and rail lines
Buried by
waste rock
Buried by
waste rock
Buried by
waste rock
                                  18

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   Utah Apex
   Mill
                              Grinding,
                              gravity
                              separation,
                              oil flotation
                                                           1.421 million
  Subsumed by
  Rogers Mill
                             Grinding,
                             gravity
                             separation
                                             Pb/Au/Ag/Cu
                                                          42,000 tons
  Subsumed by
  the pit
  Boston        1906-1910
  Consolidated
  Mill
                                                         49,739 tons    Subsumed by
                                                                        the pit
  Stewart #2
  Mill
                             Grinding,
                             amalgam-
                             ation, cyanide
                             leaching
                                                         41,667 tons
 Subsumed by
 the pit
 Highland Boy   1895-1898
 Mill
                                                         20,900 tons

                                                         ^—^——^—^——
                                                         45,000 tons
                                                                       Buried by
                                                                       waste rock
                              cyanide leach
                              Grinding,
                              flotation
                                                                       Buried by
                                                                       waste rock
New Haven
                                                                        Subsumed by
                                                                        the pit
                                                         ore capacity
                                                         = 120
                                                         tons/day
Copper Mill
 Last Chance
                                                         36,000 tons
                                                                       Buned by
                                                                       waste rock
 New England
 Gold and
 Copper Mill
                            Grinding,
                            gravity
                            separation
                                          Ag/Au/Pb/Cu
Subsumed by
the pit or
buried by
waste rock
ore capacity
= 50 tons/day
Jordan Mill     1879-1900
                           Grinding,
                           gravity
                           separation,
                           amalgam-
                           ation, cyanide
                                                         61,364 tons
                                                                      Subsumed by
                                                                      the pit.
Stewart Mill
                            Grinding,
                            amalgam-
                            ation, cyanide
                                                       68,571 tons
                                                                      Subsumed by
                                                                      pit, or buried
                                                                      by dumps
                                        19

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Spanish Mill
Telegraph
Mill
Bemis Mill
West
Mountain
Mining
Concentrator
Silver Shield
Mill
Bingham
Mining and
Milling Co
Utah
Consolidated
Gold Mine
Mill
Bingham
Gold Mining
Co
Utah
concentrator
Heaston
Concentrator
Jigs
Massasoit
Mill
Utah Mill
1874-1901
1876-1914
1898-1905
1890-?
1910-1913
1890-?
1897-1905
1895-1896
1874-1876
1896-1910
1893-1911
1874-1876
Grinding,
gravity
separation,
cyanide
Grinding,
cyanide
Grinding,
gravity
separation



grinding,
cyanide leach
Cyanide
leaching
Milling
Milling

Milling
Pb/Zn/Au/Ag
Pb/Au/Ag
Cu



Au/Ag/Cu
Au
Pb/Au/Ag
Pb/Au/Ag
Pb
Pb/Au/Ag
63,333 tons
9 1,200 tons
ore capacity
= 120
tons/day

ore capacity
= 60 tons/day
ore capacity
= 100
tons/day
ore capacity
= 100
tons/day

600 tons
4 127 tons
ore capacity
= 200
tons/day
600 tons
Subsumed by
the pit
Subsumed by
the pit
Buried by the
6 190 truck
shops
Buried by
waste rock
Subsumed by
the pit
Subsumed by
the pit or
buried by
waste rock
Buried by
waste rock
Subsumed by
the pit
Subsumed by
the pit
Buried by
waste rock
Buried by
waste rock
Subsumed by
the pit
20

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Brooks Mill
Durrani Mill
Eagan and
Bates Mill
Bingham
New England
Mill
What Cheer
Mill
Murphy Mill
CW Watson
Jig
Darrenugue
J'g
NY and Utah
Mill
1899- 1900
1877-1879
1877-1879
1905-1913
1874-1875
1874
1880
1906
1878-1881
Milling
Grinding,
Amalgam-
ation
Grinding
Milling
Grinding
Grinding,
gravity
separation
gravity
separation
gravity
separation
roast, leach
Pb/Au/Ag
Pb'/Au/Ag
Pb/Ag/Au
Pb/Ag/Au
Pb

Au
Au/Cu
Au/Ag
4 167 tons
4 167 tons
16, 667 tons
48,000 tons





Subsumed by
the pit
Subsumed by
the pit
Subsumed by
the pit
Subsumed by
the pit or
buried by
waste rock
Subsumed by
the pit
Subsumed by
the pit
Buried by
waste rock
Mobile
facility,
Buried by
waste rock
Cleaned up
during BC
Phase II
                                                                      tion
b.     Smelters
      The following smelters were known to have operated in or near Bingham Canyon-
Utah Smelter, Winnamuck Smelter, Revere Smelter, and Yampa Smelter.
                                     21

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                               HISTORIC SMELTERS
Site Name
Utah Smelter
Winnamuck
Smelter
Revere Smelter
Yampa Smelter
Years of
Operation
1871-1873
1867-1870
1880-1881
1903- 1910
Ore processed .
Pb/Ag/Au
capacity = 45
tons/day
Pb/Ag capacity
= 30 tons/day
Ag/Pb
Cu capacity =
1 000 tons/day
Process used
smelting, blast
furnaces
smelting,
cupola and
blast furnaces
roasting and
cyanide
leaching
roasting,
reverberatory
and blast
furnaces,
converting
Current status
subsumed by
the Bingham
Pit
Buried by
waste rock
Cleaned up as
part of the
Bingham Creek
Phase II action
Buried by
waste rock
 c.     Precipitation launders

       Precipitation launders also operated in the canyon. Once it was discovered that
 copper in solution from mine wastes could be recovered by reaction with scrap iron, many
 devices were installed in the canyon to precipitate the copper. Most were built and'
 operated during the period 1913 - 1925. Many of the precipitation plants obtained the
 iron needed from Hewletts Cannery in Salt Lake City and later from a source in California.
 There are some uncertainties as to the exact location of many of these sites in the Bingham
 Canyon area. In 1926, the total shipments for wet precipitation  from all sources amounted
 to 3.79 million pounds and the gross copper content amounted to 1.989 million  pounds.

       Waters from acid mine drainage were treated to recover  the copper and the spent
waters were discharged into Bingham Creek. The treatment served only to remove
copper, not other metals.  Two secondary uranium recovery plants took minewaters
previously stripped of their copper to recover uranium.  These spent waters were also
discharged to Bingham Creek.
                                       22

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PRECIPITATION LAUNDERS
Name

Boston Mine


Apex Yard


Ohio Copper
Mine













Ute Copper
Tiewaukee
Dump
McGuires Gulch


Galena Gulch







Years of
Operation
1913 -?


1916-?


1920s- 193 7













1925-1927

1919-1927?


1922- 1927?







Process

Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron












Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron





Product

Cu


Cu


Cu













Cu

Cu


Cu







Current Status

location
unknown

subsumed by pit
J r

The launder was
in the shaft of
the mine, the
discharge was
sent to Mascotte
Tunnel at Lark.
The mine has
been subsumed
by the pit.
(Mascotte
Tunnel
discharges are
not addressed in
this decision
document.)
Buried by waste
rock

Buried by waste
rock

The upper
portion of the
gulch is buried
by waste rock;
the lower
portion has been
subsumed by the
Pit. 	
         23

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Copper Center
Gulch
Main Canyon
A Pit
Drain Tunnel
Ingersoll Gulch
Starless
McGregor Plant
Robbe Cells
Winnamuck
Copper Placer
1921-1927?
1922- 1929?
1923 - 1929?
1923- 1929?
1922- 1929?
?
1933-1936
1936-1958

1892 -?
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
launder using
scrap iron
Precipitation
cells using scrap
iron
Precipitation
cells using scrap
iron
Precipitation
launder using
scrap iron
Treated waters
from the Starless
Mine
Cu
Cu
Cu
Cu
Cu
Cu
Cu
Cu
Cu
Cu
„
Subsumed by the
pit
Location
unknown
subsumed by the
pit
Location
unknown
Subsumed by the
pit
Subsumed by the
pit
Buried by a later
operation called
Robbe Cells,
area was cleaned
up during
Bingham Creek
Phase II.
	 	
Cleaned up
during Bingham
Creek Phase H.
Buried by waste
rock
Subsumed by
Bingham Pit
24

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   Cuprum Yard
   Verona Uranium
   Mill
  Yellow Cake
  Plant
              1927-7
              1969-1973
             1960s- 1989
Precipitation
plant using scrap
iron



Ion exchange,
solvent
extraction



Ion exchange

Cu





Uranium oxide





Uranium oxide

One portion has
been subsumed
by the pit; the
other portion is
buried by waste
rock
Plant
decommissioned
in 1983, site
now mostly
buried by waste
rock
cleaned up in
1995
        d.
        Minor sources
2.
        The pattern of distribution indicates that mining wastes from these upstream
 sources were the prime contributors of lead and arsenic to the channel and floodplairi of
 Bingham Creek. Minor airborne sources could contribute small amounts of these metals
 including use of lead arsenate pesticides, fallout from use of leaded fuels and fallout from
 smelters not located in Bingham Canyon.

 e.      Sources specific to Anaconda Tailings

        The sources of the contamination at Anaconda Tailings, the Bastian Ditch and the
 Bastian Sink are the Utah Apex Mill, the Bingham-New Haven Mill, their successors and
 other mills upstream of the Utah Apex Mill's flume.  The Anaconda Tailings was formerly
 a tailings impoundment designed to contain the tailings from the Utah Apex and Bingham-
 New Haven Mills and coincidentally also the tailings of all of the mills upstream of the
 Utah Apex Mill's flume.  After passing through the impoundment, waters from the mills
 were discharged back to Bingham Creek, or diverted via the Bastian Ditch southward for
 irrigation use purposes. Historic records suggest that the tailwaters, even after passing
 through the impoundment settling basins were still contaminated with tailings  The Bastian
 Sink, a topographic low near Bingham Creek, was apparently used as a catchment basin
tor tailwater overflows.

Groundwater:
       The lead and arsenic present in tailings deposited downstream from Bingham Canyon is
generally not very leachable. Although the principal aquifer underneath this area is contaminated
                                          25

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  with sulfates, acid, and metals, the source of the groundwater contamination is related to leakages
  of acid leachates produced by oxidation of metallic sulfides.  Metal sulfides are still present at
  depth in the Anaconda Tailings.  For this reason, the Anaconda Tailings were capped with HDPE
  clay and soils to prevent water and oxygen from penetrating into the sulfides. Without water and'
  oxygen, the production of acid leachates is prevented and the wastes do not mobilize to
  groundwater.

        The contaminants of concern and principal threats at the Large Bingham Reservoir include
  lead and arsenic, but also highly acidic waters and a variety of other metals. The acidic waters
  were produced through oxidation of pyritic minerals in waste rock dumps. In later years,
  Kennecott collected most of the waters for copper recovery. Excess waters were stored'in the
  Large Bingham Reservoir. These waters leaked through the sides of the Large Bingham
 Reservoir into the groundwater producing an acidic plume of groundwater elevated in acid,
 sulfates and metals.  The original reservoir was taken out of service in 1991 and replaced with a
 lined facility.

        The groundwater contamination is being addressed in a separate action.

 3.      Contaminants of concern

       The contaminants of concern  and principal threats at Bingham Creek, Anaconda Tailings
 Bastian Sink, Copperton Soils, and Bingham Canyon were lead and arsenic, both of which are
 components of mill tailings and smelter emissions.  The majority of contamination was in the
 form of various metallic salts found in soils at varying depths along the Bingham Creek drainage
 as it departs Kennecott property and travels east to the Jordan River that courses north to the
 Great Salt Lake.  These metals have been detected in groundwater along with acid and sulfate
 and surface water and plants have also been shown to contain lesser amounts of the metal
 contaminants. The metals were present in soils at potentially toxic concentrations, were mobile  in
 the surface soils from mostly surface water erosion, but also from minor airborne transport  and
 posed both non-cancer and cancer risks.  The risk-driver was soil-lead, which primarily poses
 adverse risks to normal neurologic development in young children when over-exposure occurs
 Lead and arsenic also have some (quite uncertain) carcinogenic potential, but the risks of these
 adverse cancer effects are relatively low and would be addressed (to less than 10E-4 to 10E-6) by
the remediation of the relatively greater neurologic risks posed by excess exposures to soil-lead'
this confidence is due to repeated findings of statistically significant correlations of arsenic levels
with lead levels, where arsenic was present at about 4% the level of lead in soils
                                           26

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4.     Volumes and concentrations of contaminants, extent of contamination.




Specific details about the site characteristics for each area are given below:
AREA
Bingham Creek
Phase I (OU 1)
(Residential
soils)
Bingham Creek
Phase2(OUl)
(Channel)
Bingham Creek
PhaseS (GUI)
(Residential
soils)
Lower Bingham
Creek (OU1)
Large Bingham
Reservoir (OU4)
Anaconda
Tailings (OU5)
ACTION
Removal of
contaminated
surface soils
Removal or
capping of
contaminated
soils, sediments,
tailings
Removal of
contaminated
surface soils
no action taken
Removal of
contaminated
sludges, tailings,
and subsoil, new
reservoir
constructed with
triple lining with
leak detection
Consolidation of
tailings into a
capped
repository
LAND USE
residential
recreational,
open space,
industrial,
residential
residential
Current land use
is industrial and
agricultural.
Future land use
is the same, also
recreational and
open space.
Industrial/mining
Industrial
ACTION
LEVEL
2500 ppm Pb in
soils (interim)
2000 ppm Pb in
soils (final)
1 1 00 ppm in
soils (final)
No action level
no action level,
1000 ppm lead
was used as
guide
2000 ppm Pb in
tailings
DEPTH OF
EXCAVATION
Maximum 12 -
1 8 inches,
tapering upward
near trees or
buildings
Maximum 3 feet
required. Actual
depths
sometimes
exceeded 20 feet
Maximum 18
inches.
No excavation
20-30 feet
excavated
Height of
tailings in the
repository was
40 feet.
                                          27

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Bastian Ditch
(OU5)
Copperton Soils
(OU 10)
Historic
Bingham
Canyon Facilities
(OU11,
portions)
Bastian Sink
(OU 17)
Removal of
contaminated
ditch sediments
No action taken
No action taken
No action taken
Industrial/open
space
Residential ,
Industrial/mining
Current land use
is agricultural.
Future land use
is agricultural,
open space,
recreation or
municipal waste
disposal
2000 ppm Pb in
sediments
No action level,
1 1 00 ppm lead
used as guide
No action level
No action level
Maximum 3 feet
No excavation
needed, highest
lead value was
less than 300
ppm
No excavation,
historic sites are
largely
inaccessible.
No excavation
       For those areas which required cleanup, site characteristics of the areas prior to the
cleanup are summarized below:
AREA
Bingham Creek
Phase 1 (OU1)
Bingham Creek
Phase2(OUl)
Bingham Creek
Phase3(OUl)
Large Bingham
Reservoir (OU4)
Contaminated
area
52 residences
9 linear miles of
creek channel
84 residences
80 acres
Volumes
removed or
addressed
74,000 cy
1, 048,000 cy
1 00,000 cy
2,660,000 cy
Maximum Pb
17,000 ppm
4 1,600 ppm
16,000 ppm
3, 150 ppm
Maximum As

630 ppm

471 ppm
                                          28

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Anaconda Tails
(OU5)
Bastian Ditch
(Kennecott)
(OU5)
Bastian Ditch
(ARCO) (OU5)
96 acres
1/4 linear mile
1 linear mile
-1, 530,000 cy
5,850 cy
3 9,000 cy
31,800ppm
28,000 ppm
20,307 ppm
2,230 ppm
1,100 ppm

Site characteristics of the areas where no action was needed are given below:
AREA

Lower Bingham
Creek (portion
ofOUl)




Copperton Soils
(OU 10)







Historic
Bingham
Canyon facilities
(OU11)

Contaminated
area
~23 acres





none








original
locations spread
over an 11,000
acre area

Approximate
volume
36,600 cy





none








Original
production
records indicate
in excess of
3, 8 14,000 tons
Lead distribution

Surface:
34% above 2000
ppm lead
median - 1400
ppm
average- 1801
ppm
All lead values
were lower than
253 ppm lead,
significantly
lower than the
Bingham Creek
final action level
of 11 00 ppm
lead
unknown -
original wastes
are inaccessible
for study

Land Use

agricultural and
industrial





residential








industrial/mining



                                   29

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Bastian Sink
(OU 17)







~30 acres







48,400 cy


r




Surface:
22% above 2000
ppm
median = 897
ppm
average =1347
ppm
Depth = 1 foot
or less
agricultural







 5.     Migration pathways.

       At mills, the ore is crushed and ground into small particle sizes and the economic minerals
 are separated out via flotation, leaching, or gravity separation. The non-economic particles are
 typically slurried to the nearest water body or tailings pond.  The particle sizes are of a range
 easily transported by water.  The tailings were washed downstream and then were deposited in
 the flpodplain downstream as the waters receded.  At some locations, the layer of tailings was
 thin; in other locations near the channel, the tailings could be 20 feet thick.  Agricultural practices
 along the creek mixed the tailings into the soils.  Residential neighborhoods were built on the
Bingham Creek floodplain. Because of the small size of the tailings particles, resuspension and
remobilization during flood events or rainstorms was a distinct possibility.  Although the upper
portions of the creek passes through industrial and agricultural land, the channel  in these areas
was cleaned up also because of the possibility that these wastes could move into  downstream
neighborhoods.

F.     SUMMARY OF SITE RISKS

       1.      Data and Studies used for estimating risk.

              Parties involved with this site generated some of the most comprehensive, efficient,
      and cost-beneficial data associated with a Superfund risk evaluation. Risk managers
      recognized the value of early and focused involvement of stakeholders and risk assessors,
      and initial working committees were established that proved quite successful:  (1) the Risk
      Assessment Task Force; and (2)  the Ecological Technical Assistance Group. Members
      had relevant scientific expertise,  avoided excessive legal and policy biases, and fully
      represented science issues for the involved parties. Local, regional,  and national experts
      participated in these committees.

             The Risk Assessment Task Force recommended that the following studies and data
      collection be performed to be used in EPA decisions at these sites:
      (1) nature and extent of contamination; (2) fate and transport of the  contaminants from
      their source areas to where they were ultimately found; (3) geochemical speciation of the
      metal salts; (4) determination of the bioavailability of lead and arsenic using the juvenile

                                              30

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  swine model; (5) garden vegetable uptake of co-located metals (both greenhouse and in-
  situ studies were performed);  (6) an extensive blood lead and urine arsenic study of
  exposed, potentially exposed,  and background children living in the area along with
  appropriate statistics; (7) a study of the soil/household dust relationship in the area- (8)
  statistics involving exposure frequency and duration at the site; and (9) a comparison of
  several model predictions with actual distributions.

         The IEUBK (Integrated Exposure Uptake Biokinetic) Model was used with the
  site specific data to develop a PRO (Preliminary Remediation Goal) of 1100 - 1300 ppm
  lead in soil. The model predicted that this concentration range of lead in soil would yield
  <5% of exposed children with  10 ug/dL or greater blood lead levels. EPA's risk
  management goal dictates that cleanups should result in <5% of exposed children with
  blood lead exceeding 10 ug/dL.  The exact concentration of lead in soils and/or dust at any
  site will vary depending on site specific conditions. In the case of Bingham Creek  the
  soils contained lead species such as lead phosphates which were less bioavailable in the
 juvenile swine studies than assumed by the default value in the model.  RMEs  (Reasonable
 Maximum Exposures) and Central Tendency Analyses were used in the model
 calculations. Model results also revealed that the major exposure pathway for young
 children at the site was soil ingestion,  largely resulting from mouthing behavior  Lead was
 not detectable in the municipal  water supply and ingestion of lead from homegrown
 vegetables was also a minor pathway. For more detail, refer to the Bingham Creek Phase
 III Endangerment Assessment.

        The PRO range of 1100 ppm - 1300 ppm of lead in soils was presented to a
 delegation of Bingham Creek residents.  The reasons for the uncertainties were explained
 (b.oavailabihty uncertainty, soil/dust variability, etc.).  The residents preferred the more
 conservative value given the uncertainty.  Residents were also asked if action levels for
 different land uses should  be developed. They indicated that all of the land be considered
 residential since the vacant and  industrial lands were surrounded by residential  property
 They did not want the residential character of their neighborhoods to change.

       The results of these studies, models, and public input were used to set a final
 action level of 1100 ppm lead in soils for residential land use. Vacant lands within the
 residential neighborhoods  were considered to be residential. Vacant lands outside the
 residential area were evaluated on the basis of their current and future land use  The 2000
 ppm lead level previously used in the removals at open space, recreational, and industrial
 lands at this site was considered to be sufficiently protective for these land uses  A
 preliminary calculation performed recently  with newer information and models confirms
 that this level is protective for these land uses.

       Arsenic was also identified as a contaminant of concern at these sites EPA
 discovered that there was a strong relationship between the lead concentrations and the
arsenic concentrations in the soils with arsenic levels about 4% of the lead concentrations
                                        31

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 A few urine arsenic samples from the juvenile swine study (used primarily for lead
 bioavailability) provided an estimate of arsenic bioavailability. Based on this and other site
 specific conditions, a PRO (Preliminary Remediation Goal) of 100 ppm arsenic was
 calculated. Again, the acceptable risk range for potential carcinogens in the National
 Contingency Plan is 10E-4 to IOE-6. The action level set for arsenic at the Bingham
 Creek residential sites was 100 ppm arsenic which is below the 10E-4 risk level.  The
 actual cleanup achieved levels significantly lower than this because the risk driver was
 lead.  Note that 4% of the lead action level of 1100 ppm Pb is 44 ppm arsenic. Other
 contaminants (e.g. cadmium) were present at low levels below any risk-based
 concentrations in soils.

 2.      Environmental Evaluation

        The majority of this site had land uses that provided relatively little habitat for
 wildlife where meaningful contact with hazardous contaminants would  occur. Thus, a
 qualitative ecological risk evaluation was performed by the EPA Region VTJ3 site
 toxicologist in the Phase III Endangerment Assessment.  Because the Bingham Creek
 Phase I and Phase III areas and land-use were largely residential with limited opportunities
 for exposure to wildlife, there were no specific sampling or monitoring on ecological
 receptors.  Kennecott did conduct a site-wide ecological risk  assessment for those areas of
 the larger Kennecott South Zone and North Zone which had substantial wildlife habitat.
 Although those studies included both phytotoxicity and uptake estimations, the
 information is not relevant to the portion of the site included in this decision document.
 Although wildlife occasionally visit the area, the land is not primarily wildlife habitat.  The
 area is located in suburban cities near Salt Lake City. Bingham Creek is normally dry
 except following storm events.  The creek serves  mainly as a drainage ditch and does not
 support aquatic life.  Aquatic impacts in the Jordan River are  possible following storm
 events or floods. The Jordan River is not covered in this  decision document and impacts
 there were not evaluated. Thus, EPA concludes that there are no actual or threatened
 releases from these OUs that pose a present or potential future threat to the environment
 within the coverage of this document.

 3.     Rationale for the no action decision

       The no action decision for the OUs covered in this decision document is based on
 four considerations: (1) at some OUs, the removal actions were designed to achieve final
 remedial cleanup goals;  (2) at one OU, initial studies revealed that the concentrations of
 contaminants were not high enough to pose a risk to health; (3) in several locations, the
land use was not residential currently or anticipated to be  residential  and there is little
exposure; or (4) at one OU, the waste locations were not  accessible to the public or
workers.
                                        32

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        There were three OUs at which removal actions were designed to accomplish both
 short term and long term remediation goals. This was done primarily to avoid the need for
 remobilization and thus reduce costs.  At Bingham Creek (OU 1), before initiation of the
 last removal action, there were extensive risk assessment and risk management activities to
 determine a final action level of 1100 ppm lead. The work included excavation of
 contaminated soils down to a maximum of 18 inches, replacement with clean soils, and
 revegetation. The purpose of this action was to break the exposure pathway to young
 children playing in their yards. The affected cities agreed voluntarily to use their land use
 and building permit authorities to prevent disturbance of any underlying contamination.  In
 addition, contamination remaining in Bingham Creek channel itself was removed down to
 a depth of at least 3 feet, with remaining material capped under clean fill.  This was done
 not only to protect occasional visitors from direct contact with the wastes, but also
 prevent downstream migration of the materials into residential neighborhoods during
 storm conditions.  A major goal of this project was to prevent any possible
 recontamination of residential soils in the watershed.  A final action level of 2000 ppm lead
 was based on a recreational and open space land use. At Large Bingham Reservoir
 (OU4), all contaminated sludges, tailings, and underlying soils were removed from the
 site.  The reservoir was then reconstructed using a triple lining system with leak detection.
 In addition to the leak detection system, downgradient monitoring wells were also
 installed.  The continued integrity of the reservoir is covered under a state groundwater
 permit which requires any leaks to be repaired.  The primary goal of this project was to
 prevent any future contamination of groundwater associated with this reservoir.  At
 Anaconda Tailings (ARCO Copperton Tailings, OUS), the tailings ponds were capped
 with clay, geotextile liners, and soil to prevent infiltration of meteoric water into the
 tailings.  In addition the exterior of the capped repository was armored with rip rap, with
 runoff and run on controls.  The design of this remedy was to prevent any direct contact
 with the waste by visitors, workers, and wildlife, to prevent any future migration of
 contaminants to groundwater and to prevent any off-site migration associated  with a 100-
 year storm event.  Maintenance of the facility is provided by the property owner, and Salt
 Lake County is using its land use and building controls authorities to prevent disturbance
 of the repository.  At these areas, no further action is needed because the exposure
 pathways and potential future exposure pathways have been virtually eliminated.

       At one operable unit, Copperton Soils (OU 10), a residential area, studies revealed
 that the concentrations of contaminants were not sufficiently elevated to pose a risk to
 children. The highest lead contamination found in soils at this site was 253 ppm lead, well
beneath any level of concern.

       At two locations. Lower Bingham Creek (a small portion of OU 1), and Bastian
 Sink (OU 17), the land use is agricultural. For several reasons (unrelated to
contamination) these two areas are not attractive for future residential development.  No
action was needed  at these locations because exposure is very low and limited to episodic
visits by adults. In addition, average lead values for these areas are beneath 2000 ppm


                                        33

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       lead, the action level used for recreation and open space areas of the Bingham Creek
       channel.

              At one OU, Bingham Canyon Historic Facilities (OU 11), most of the facilities are
       inaccessible to workers and visitors. This is in an area of active mining operations and the
       older historic facilities have either been mined away by the open pit or have been buried by
       waste rock from the newer mining activities.  If wastes still exist in these locations, they
       are not accessible and there are no exposure pathways.  Where wastes remain at
       concentrations of concern, they were specifically excluded from this no action decision
       document.
      4.     Previous actions taken at the site to reduce unacceptable risks.

                    Previous response actions were taken in order to reduce or eliminate risks
      at the site.  No action was taken at certain areas where there was little risk, based on
      present and future anticipated land use. The objectives of the response actions are
      described below:
AREA
NATURE OF RESPONSE
                                                     RATIONALE
Bingham Creek
Phase 1 (OU1)
1. Removal of surface soils in
Bingham Creek residential areas
and neighborhood parks with lead
exceeding 2500 ppm down to a
maximum depth of 18 inches. This
was an interim emergency response.
                 2. Aid the city in development of
                 special conditions for building in
                 this area and provide the city with
                 details of waste locations.
 1. A.  Prevent exposures of children
 to unacceptable levels of lead via
 inadvertent ingestion of soils by
 children sticking dirty toys or hands
 into their mouths.  Note: this interim
 action was taken to remove the most
 contaminated soils while scientific
 studies were launched to determine
 the final action level.

 B. Prevent exposure of children and
 adults to lead via ingestion of
 homegrown produce grown in
 contaminated soils.

2. Prevent recontamination of
surface soils during construction of
new buildings at the site.
                                         34

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 Bingham Creek
 Phase 2 (OU1)
 1.  Removal of surface soils in
 Bingham Creek channel with lead
 exceeding 2000 ppm down to a.
 depth of 3 feet. This was an
 emergency response, but also  :
 designed to be a final action.
                  2.  Erosion controls added to
                  protect the remedy.

                  3.  Aid city in the development of
                  building permit conditions and
                  provide details of waste locations.
 1.  A. Prevent exposures of children
 to unacceptable levels of lead via
 inadvertent ingestion of soils due to
 children putting dirty hands or toys
 into their mouths.  This area has
 some recreational use by people in
 nearby residential neighborhoods.

   B. Prevent mobilization of
 contaminated soils into downstream
 neighborhoods during storm events.

 2. Protect the cap from erosion
 during storm events.

 3. Prevent exposures due to
 additional development along the
 channel.
Bingham Creek
Phase 3 (OU1)
 1. Removal of surface soils in
Bingham Creek residential areas
and neighborhood parks with lead
exceeding 1100 ppm down to a
maximum depth of 18 inches.  This
was a final response.  All
properties originally slated for
Bingham Creek Phase 1 but not
remediated due to access refusal
were also remediated. There were
no access refusals during this final
phase.

2. Aid city in the development of
special conditions for building in
this area to the city and provide
details of waste locations
1. A.  Prevent exposures of children
to unacceptable levels of lead via
inadvertent ingestion of soils by
children sticking dirty toys or hands
into their mouths.

B. Prevent exposure of children and
adults to lead via ingestion of
homegrown produce grown in
contaminated soils.
                                                    2. Prevent recontamination of
                                                    surface soils during construction of
                                                    new buildings at the site.
                                         35

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 Lower Bingham
 Creek (portion
 of OU 1)
 No action taken.  Data on waste
 locations were provided to the city
 for possible use in redevelopment
 planning for the area.
 The location is in the Jordan River
 floodplain and is currently
 agricultural and industrial.  This is a
 Brownfields Site.  There is no
 current risk due to the land use. The
 city is developing a master plan for
 this area to ensure that any future
 development does not increase
 exposure to the waste.
Large Bingham
Reservoir (OU4)
Water drained from reservoir and
sludges, tailings, and contaminated
subsoils were removed.  A new
facility was built using a triple lined
system (clay and two HOPE liners
with a leak detection between the
two HDPE layers).  On-going
monitoring of leaks is required
under provisions of a state
groundwater permit.
 This action was taken to eliminate a
 source of groundwater
 contamination and to prevent a
 recurrence of leaks to groundwater.
Anaconda
Tailings (OU5)
1.  Tailings were consolidated into
one area of the site and capped with
HDPE, clay, and soil.  The action
level was 2000 ppm lead.
                 2. Rip-rap protects the upgradient
                 sides of the cap.
                 3. Run-on and run-off controls
                 were installed surrounding the cap.
 1. A.  Capping of the waste
 prevents direct exposure of the
 wastes to humans and wildlife thus
 minimizing risk.

 B. Capping of the waste with
 impervious liners prevents
 groundwater contamination and
 potential health impacts to
 downgradient well owners.

2. Reduces the potential for
migration of the waste downstream
during flood events.

3. Protects the cap from erosion
during rain events.
                                         36

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 Bastian Ditch
 (portion of OU5)
 1. All of the tailings were removed
 from the ditch on ARCO property
 and on Kennecott property
 downgradient to the Randolph
 Peterson Gate.  The action level
 was 2000 ppm (industrial land use)
 1. A. Prevent direct exposure of the
 wastes to humans and wildlife.

 B.  Prevents recontamination of
 previously cleaned up sites
 downgradient of the ditch.
Copperton Soils
(OU 10)
No action taken
 Although historic tailings were
 located toward the east side of
 Copperton, no action was needed
 because the concentrations of lead
 were well beneath any health
 concern.
Historic
Bingham Canyon
Facilities (OU
11)(except
those specifically
excluded from
this decision)
No action taken
Wastes remaining in Bingham
Canyon by historic facilities are no
longer accessible, and present no
risk to human health or the
environment. The wastes are either
subsumed by the pit (mined away),
buried by the current Kennecott
waste rock dumps, or buried by
current Kennecott support facilities.
The migration potential for wastes at
these sites is low. Note: the total
wastes produced at these historic
facilities is on the order of 3.8
million tons. The current waste rock
dump which buries these sites is
about 3.5 billion tons. Wastes from
historic sites, if buried, represent
0.1% of the total waste  at the site.
                                         37

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Bastian Sink
(OU 17)
      No action was taken.  The data will
      be provided to the owners and the
      county for use if the land use   .
      changes in the future.
There is no current risk at the site
because the land use is agricultural.
Ideas for future land use include
continued agricultural use, expansion
of the nearby Trans Jordan Landfill,
industrial use and open space. There
are no plans to use this area for
residential purposes due to its
location near waste storage and
disposal facilities.  Special conditions
on building permits will prevent
exposures if the land use should
change in the future. Unlike
Bingham Creek, the migration
potential is low.
     5.
Five Year Review Issues:
            Several of the areas covered in this Record of Decision are subject to the 5-year
     review process because there are wastes left in place. The issues for consideration are as
     follows:
AREA
Bingham Creek (OU1)
Anaconda Tailings
(OU5)
Bastian Ditch (portion of
OU5)
5-YEAR REVIEW ISSUES
Wastes are left on a few properties. The wastes exist underneath a
soil cap. Construction activities on these properties with wastes
may require special conditions in building permits administered by
the cities. Is this concept continuing to work? Have residents
installed gardens in inappropriate locations? Are further
institutional controls needed for this? Are erosion controls in the
creek channel working? Has land use changed in lower Bingham
Creek?
Wastes are left in place underneath a cap composed of HDPE, clay
and soil and are protected by runoff and run-on controls. This
property is not suitable for development. Does the cap remain
protective?
Most of the wastes have been removed to repositories. The only
wastes remaining are under State Hwy 1 1 1 under road base and
asphalt. Do these conditions still remain?
                                          38

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  Bastian Sink (OU 17)
Wastes exist at the surface on about 30 acres of the 145 acres
surveyed; most of the wastes are confined to the top foot. Current
land use is agricultural.- Special conditions in building permits
administered by the county are required for any change in land use.
Has the land use changed? Is it compatible with the pattern of
existing contamination?
G.     DESCRIPTION OF NO ACTION ALTERNATIVE

       EPA has determined that no further action is required at these operable units. For
Bingham Creek, Anaconda Tailings, Bastian Ditch and Large Bingham Reservoir, previous
response actions have eliminated the risks at these sites. For Bastian Sink, Copperton Soils,
Lower Bingham Creek and portions of Bingham Canyon Historic Facilities, no action is
appropriate due to lack of risk associated with current land uses.

H. EXPLANATION OF SIGNIFICANT CHANGES

       The selected remedy documented in this Record of Decision is the same as the preferred
alternative presented in the Proposed Plan.  There were no significant changes.
                                          39

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                         ID.  RESPONSIVENESS SUMMARY

 INTRODUCTION:                            -

        The Proposed Plan explaining EPA's and UDEQ's preferred remedy for these portions of
 the Kennecott South Zone was mailed to affected residents, public officials and media on May 1,
 1998. An advertisement concerning the public meeting and the public comment period was
 carried by the Salt Lake Tribune and Deseret News on May 6, 1998.  The public meeting was
 held on May  13, 1998, at West Jordan City Hall. Comments on EPA's and UDEQ's Proposed
 Plan could be given orally at the public meeting or by writing to EPA. The public comment
 period started on May 5, 1998, and closed on June 5, 1998.

 ORAL COMMENTS DURING THE PUBLIC MEETING:

       The public meeting agenda had four parts: (1) Introductions of EPA, BOR, UDEQ, City
 of West Jordan, and Kennecott staff; (2) slide show and summary of cleanup activities and the
 proposed alternative; (3) questions from the audience; and (4)  the formal receipt of oral
 comments.

       There were no oral comments made during the formal comment section of the public
 meeting.

 WRITTEN COMMENTS SUBMITTED TO EPA:

       One written comment was received by EPA during the public comment period.

       COMMENTER:    James L. Warlaumont, Esq.
                         Appel and Warlaumont
                          1100 Boston Building
                         9 Exchange Place
                         S alt Lake City, UT 84111

                         (Attorney for four families in Abeyta, et al. vs. ARCO, et al.
                         Civil Case #960901485CV)

       DATE:            June 5, 1998, received by EPA June 8,  1998


       Mr. Warlaumont submitted some sampling data associated with JV-8 (3065 W 8600 S,
West Jordan), JV-10 (Candido  Abeyta's former property, address not given) and JV-14 (2947 W
8600 S, West Jordan).
Responsiveness Summary

-------
        He pointed out that the results indicate that "there are still many areas on these properties
 where concentrations of minerals exceed the levels described on page 7 of the flyer [Proposed
 Plan]." Page 7 refers to a final cleanup level of 1 lOOmg/kg lead in soil.

        He requested that this information "be considered as part of the final remedy selection
 process".

 EPA RESPONSE:

        The goal of the Bingham Creek residential  Soil cleanup activities was to prevent the
 exposure of residents and their children to unsafe amounts of lead and arsenic. EPA focused on
 the top 6 inches of residential yards as the area where people were most likely to be exposed to
 the contaminants in the soil. In designated garden  areas, EPA focused on the top  18 inches to
 allow for tilling of the soil. The specific goal of this cleanup was to bring the average
 concentration within each exposure unit to beneath the action level of 1100 ppm lead in the
 surface soils.  The use of averages allowed EPA and the individual property owners some
 flexibility in the design of the cleanup protocol for each property.

        A complete removal of surface contamination requires removal of all trees, shrubs,
 flowerbeds, fences and structures. Because the objective was to achieve the average
 concentration within the yard, the homeowner could choose to save trees, shrubbery,  decorative
 walls, and other structures. EPA prepared detailed design drawings of the yards which depicted
 all structures, tress, gardens, etc., in the yard.  No  construction work was begun on any property
 until the homeowner and EPA agreed on which plants and structures would be saved and which
 would be replaced. The drawings were altered to reflect these decision. The final designs were
 approved in writing by each homeowner prior to implementation of the work.

       In order to save the plants and structures designated by the homeowners, EPA often had
 to use hand tools to carefully remove contaminated soils from around these items.  However, it
 was not possible to remove all the contamination without risking either killing the plants or
 undermining the retained structures. Therefore, it was anticipated that some higher levels of
 contamination would exist around those plants and  structures although the average soil
 concentration in the total yard would be at safe levels.

       The new sampling data submitted to EPA indicates several spots where the concentrations
 exceeded EPA's action level.  This is not necessarily inconsistent with the cleanup objectives if
these samples were collected in the areas where the homeowners requested that the trees or walls
be saved.  The maps showing sampling locations submitted  along with the Commenter's data did
not show the location of these trees or walls.  Therefore, EPA requested additional information
from the Commenter concerning the exact location  of the samples relative to these  plants and/or
structures.  On July 24, 1998, the Commenter answered that the locations of these  structures or
plants relative to the sampling locations were not available.

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        The scale of the property maps and sampling locations submitted by the Commenter did
 not permit a precise comparison of EPA's design drawings to these maps, but some rough
 approximations could be made. EPA then evaluated the data submitted to determine whether
 these results were consistent with (1) the goal of the removal action and (2) the specific individual
 designs.

        The goal of the removal action was to cut off the exposure route to the residents.  While
 EPA removed up to 18 inches in some locations, only 6 inches is needed to cut off the exposure
 route, particularly in sodded lawn areas.  The Commenter's data containing sampling results from
 0-6 inches, 6-12 inches, 12-18 inches, and 18-24 inches.  In presenting the statistics for these data,
 the Commenter then presented tables in which the results from all depths were used.  When this
 technique is used, all of the yards had lead values in excess of EPA's final action level of 1100
 ppm lead. However, EPA did not address any soils at the 18-24 inch depth and in some yards did
 not address soils beneath 12 inches.  When the Commenter's data from the crucial top 6 inches
 alone are averaged, the story is different.  In the top 6 inches, JV-8 contained an average of 761
 ppm lead; JV-10 contained an average of 49 ppm lead; and JV-14 contained an average of 1557
 ppm lead. Only in the yard  of JV-14 did the top 6 inches of soil apparently average above the
 1100 final action level. This assumes that representative sampling was conducted by the
 Commenter. Further examination of the sampling map of JV-14 revealed that many of the
 commenter's samples appeared to have been collected at or near plants or structures retained at
 the owner's request. When these samples were deleted from the data set, the average lead level at
 JV-14 dropped to 201 ppm  lead.

       In a more detailed examination, of the  10  sample locations at JV-8, two yielded samples
 above action levels at the surface. Both of these two locations were near or at plants and
 structures retained at the owner's request. Of the 8 sample locations at JV-10, none of the
 samples exceeded action levels at the surface.  Of the 10 sample locations at JV-14, five yielded
 samples above the action levels at the surface.  All five of these locations were near or at plants
 and structures retained at the owner's request. EPA concludes that the overall goal of the
 removal action to prevent exposure of the residents to unsafe levels of lead was achieved.

       Next, EPA examined the Commenter's data to see if the results were consistent with the
 original designs for these properties.  In general, the original design for these properties called for
 removal of the top  12 inches and replacement with clean soils. For JV-8, of the 10 samples, five
 contained lead  levels above the action level.  Two of the five were  near plants retained at the
 owner's request; the other three  were underneath gravel and road base. These results are
 consistent with the design.  For JV-10, of the 8 samples, five contained lead levels above the
 action level.  Of these five, one was near a plant retained at the owner's request; one was
underneath a gravel driveway;  and two were close to or underneath the owner's house.  One
 sample was located, according to the  Commenter's map, in a garden area. This garden is not
shown at all on the original detailed design drawings and must have been installed by the property
owner following the removal action.  Furthermore, the original design drawing shows  a third shed
located on JV-10, and the current drawing from the commenter shows that the shallow samples

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 were collected in the vicinity of the shed that is no longer present. Also, soil from the crawl space
 on JV-10 was removed to allow placement of a thin concrete cover (shot-crete). It is EPA's
 understanding from the discussions with the original owner, that the owner removed some of the
 concrete cover that EPA installed in the crawl space.  For JV-14, of the 10 samples, nine
 contained lead levels above the action level in the top 12 inches.  Of these nine samples, seven
 were collected at or near plants retained at the  owner's request; and the other two were near
 structures also retained at the owner's request.

       EPA concludes that the sampling data submitted by the Commenter are consistent with the
 original designs for these properties. It is clear that the garden at JV-10 was installed sometime
 after the removal action was done because it is not shown on the original design.  Because EPA
 anticipated that in garden areas, the residents might till the ground, EPA excavated these areas
 down to 18 inches and took care to note these areas on the design drawings. The situation is
 complicated by the fact that property ownership has changed since the original remediation and
 that a structure appears to have been removed and may have exposed some soil that could not be
 accessed during the removal action. It is not clear whether the old property owner installed the
 garden with full knowledge or new property owner installed the garden without this knowledge.
 An attempt was made to clarify this situation by a visit to this property.  No garden area could be
 found. No action was taken.

       Although these types of situations are inevitable, it is EPA's view that any disturbance of
 the remedy is the ultimate responsibility of the homeowner.  It may be necessary for a homeowner
 to dig through the clean fill and bring up contaminated soils; however, it is also the responsibility
 of the owner to replace the lead contaminated soil and clean cover or remove the newly exposed
 contaminated soil to the locally permitted solid  waste landfill.  It is also the owners'  responsibility
 to inform any new owner that contamination does exist underneath the fill.  In this case, the
 homeowner should contact EPA or UDEQ to ascertain what he can do to protect his family from
 the contamination caused by the disturbance of the remedy.  In this case, the contamination is
 beneath 6 inches, but root vegetables may penetrate into the contaminated zone and require
 washing before ingestion.

       EPA is making one addition in the decision document based on this comment. EPA will
recommend that during the 5 year review EPA determine if installation of gardens in inappropriate
places is a common occurrence and worthy of development  of additional institutional controls.

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