PB99-963102
                              EPA 541-R99-002
                              1999
EPA Superfund
      Explanation of Significant Difference
      for the Record of Decision:
      NL Industries Site
      Pedricktown, NJ
      6/21/99

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               EXPLANATION OF SIGNIFICANT DIFFERENCE

                   NL Industries Superfund Site
               Pedricktown,  Salem County,  New Jersey
 INTRODUCTION
 The purpose of this document,  called an Explanation of
 Significant Difference (ESD),  is  to provide an explanation of a
 change the  United States  Environmental  Protection Agency (EPA)
 has made  to a portion of  the  remedy selected in the July 8,  1994
 Record of Decision (ROD)  for  the  NL Industries,  Inc.  Superfund
 Site (Site).   This ESD is issued  pursuant  to Section 117(c)  of
 the Comprehensive Environmental Response,  Compensation,  and
 Liability Act of  1980,  as amended (CERCLA)  42 U.S.C.  §9617(c)  and
 by Section  300.435 (c) (2) (i) of the  National Oil and Hazardous
 Substances  Pollution Contingency  Plan (NCP)  40 C.F.R.
 §300.435(c) (2) (i) .

 The Site  is located on Pennsgrove-Pedricktown Road  in
 Pedricktown,  Salem County, New Jersey.   EPA is the  lead  agency
 for the remediation of the Site,  with the-New Jersey Department
 of Environmental  Protection  (NJDEP)  supporting EPA  in the
 remediation.

 The ROD,  which was issued by EPA, addresses the cleanup  of
 contaminated  soil,  stream sediment  and  groundwater  at the  Site.
 This ESD  pertains only to that portion  of  the remedy contained in
 the ROD that  addresses  contaminated soil and sediment.

 The ROD-specified remedy  calls for  the  excavation of  soil  and
 sediment  containing lead  at levels  exceeding 500 parts per
 million (ppm),  on-site  solidification/stabilization of those
 soils determined  to be  hazardous, and disposal  of all excavated
 soil in a landfill  to be  constructed at the Site.   However, as  a
 result  of newly obtained  information, EPA  believes  an alternative
 involving the  disposal  of the  excavated soil  and sediment  in  a
 landfill  located  off-site to be cost-effective, equally
 protective,  and more quickly implemented than disposal on-site.
 Therefore,  this ESD revises the ROD to provide  for  the off-site
 disposal of all excavated soil and  sediment.

 Summary of  Site History.  Pont-amination Problems, and  Selected
 Remedy

 The NL  Industries,  Inc. (NL)  Superfund Site  is an abandoned,
 secondary lead smelting facility, situated  on 44 acres of  land  on
 Pennsgrove-Pedricktown Road,  in Pedricktown,  Oldmans  Township,
New Jersey.   The  Delaware River,  abandoned  and active industrial
 facilities,  woodlands and residential areas are located  in the
vicinity of the Site.

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 In 1972, the facility began the operation of recycling lead from
 spent automotive batteries and other lead-bearing materials   The
 batteries were drained of sulfuric acid,  crushed and then
 processed for lead recovery at the smelting facility.   The
 plastic arid rubber waste materials resulting from the  battery
 crushing operation and waste from the smelting process were
 disposed of in an on-site landfill.

 NL ceased smelting operations at the Site in 1982.   In October
 1982, NL entered into an Administrative Consent Order  (AGO)  with
 NJDEP to conduct a remedial program to address the  Site soil,
 paved areas,  surface water runoff,  the landfill and groundwater
 In December 1982,  the Site was proposed for inclusion  on the
 National Priorities List.

 In February 1983,  the facility was sold to National Smelting of
 New Jersey (NSNJ)  and lead smelting operations recommenced.
 NJDEP entered into an amended AGO with NSNJ,  National  Smelting
 and Refining Company,  Inc.  (NSR),  which was NSNJ's  parent
 company,  and NL.   The amended AGO clarified the environmental
 responsibilities  of NSNJ and NL.   NSNJ ceased operations at  the
 site in January 1984,  and filed for  bankruptcy along with NSR  in
 March 1984.

 In April 1986,  NL entered into an Administrative Order on Consent
 (AOC)   with EPA,  whereby NL assumed  responsibility  for conducting
 a  Remedial  Investigation and Feasibility  Study (RI/FS)  for the
 Site,  which EPA designated as Operable Unit One (OU1),  with  EPA
 oversight.  Recognizing  the size  and complexity of  the Site, EPA
 is addressing its  remediation in  phases,  or operable units.  OU1
 addresses site-related contamination in various media  such as
 soil,  stream  sediment, surface water and  groundwater.   The OU1
 RI/FS  was completed in July 1993.  Operable Unit Two (OU2)
 addresses the on-site  slag  and lead  oxide piles as  well  as
 contaminated  debris and  surfaces.  The OU2  Focused  Feasibility
 Study  was completed in July 1991.

 In September  1991,  EPA issued the Operable  Unit  Two  Record of
 Decision  (OU2 ROD),  which selected a remedy for cleanup  of on-
 site slag and lead oxide piles  as well  as  contaminated debris  and
 surfaces.  In March 1992, EPA issued an BSD to permit  additional
 alternatives  for remediation  of the  slag.   These  alternatives
 included; off-site treatment  with off-site  disposal; and on-site
 treatment with off-site disposal.  At  the  same  time, EPA ordered
 a  group of 31 Potentially Responsible  Parties  (PRPs) to  perform
 the remedy selected in the OU2 ROD.  The OU2 remedy was  completed
 in September  1995  and included: on-site stabilization  and  off-
 site disposal of slag piles;  off-site recycling  of lead  oxide
piles and other lead-bearing  waste;  decontamination of buildings,
paved surfaces, equipment and debris; dismantling of buildings
with recycling of  scrap metal; and off-site treatment  and
disposal of standing water and wash water.    •

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 EPA also conducted a multi-phased Removal Action at the Site to
 address several conditions that presented an imminent risk to
 public health and the environment.   EPA conducted Phase I of the
 Removal Action in March and April 1989.  Phase I consisted of
 construction of a chain-link fence to enclose the former smelting
 plant and spraying or encapsulation of the on-site slag piles
 Encapsulation of the piles provided temporary protection from"
 wind and rain erosion and contaminant migration.   In November
 1989, EPA began Phase II of the Removal Action.   This phase
 consisted of additional encapsulation of the slag piles,  securing
 the entrances of the contaminated buildings,  and removal of over
 40,000 pounds of the most toxic and reactive materials.

 During March of 1991,  EPA performed Phase III of the Removal
 Action.   Damages to the perimeter fence were repaired,  a new
 entrance gate was installed,  and all on-site containers stored  in
 open areas were emptied and staged  under existing covered areas
 Sand/gravel berms were installed around these materials to deter
 their release.   During July of  1992,  Phase IV of  the Removal
 Action reinforced the  slag bin  retaining walls which were in
 danger of collapsing.

 Phase V of the  Removal Action,  which began in the Fall  of 1993,
 resulted in. the removal of the  most highly contaminated stream
 sediment from the West Stream,  which is located  adjacent  to the
 Site and is believed to have  been contaminated by runoff  from the
 Site.   Excavated sediment has been  disposed of off-site.

 The  OU1  RI was  a comprehensive  study which determined the nature
 and  extent of Site-related contamination.   The RI revealed the
 presence of contaminants,  primarily lead and  cadmium, in  various
 media  at the Site.   Lead was  detected in Site  soil at
 concentrations  as  high as 12,700  parts  per million (ppm).   In
 addition,  lead  was detected in  sediment from  the  West Stream at
 concentrations  up  to 23,700 ppm.

 The  OU1  RI  also concluded that  the  Site is  underlain by three
 hydrogeologic units: the  unconfined (water table)  aquifer;  the
 first  confined  aquifer;  and the second  confined aquifer.
 Groundwater sampling results  indicated  the presence of a
 contaminant  plume  in the  unconfined aquifer below  the Site.
 Groundwater from the unconfined aquifer  contained  lead and"
 cadmium  at  concentrations  as high as 4,400 part per billion  (ppb)
 and  997  ppb, respectively.  These concentrations exceed the
 applicable  drinking water  standards of  10 ppb and  4 ppb for  lead
 and  cadmium, respectively.  Furthermore, a localized area of
 elevated volatile organic  compounds  (VOCs) was found in the
vicinity of  two monitoring wells.  VOCs detected include 1,1,1-
 trichloroethane, 1,1-dichloroethane, 1,1- dichloroethylene,
 tetrachloroethene and vinyl chloride.

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 Lead,  the primary contaminant of concern at  the  Site,  is
 classified as a probable human carcinogen.   Furthermore,  exposure
 to lead can cause noncarcinogenic effects including  alterations
 in red blood cell production and the central nervous system.
 High concentrations of lead in the blood can cause severe,  '
 irreversible brain damage and possible  death.  The Quantitative
 Risk Assessment conducted for OU1 indicated  that the hypothetical
 long-term use of contaminated groundwater for potable purposes
 would result in unacceptable carcinogenic and noncarcinogenic
 risk to the receptors.   Furthermore,  a  child living  on-site would
 be exposed to unacceptable risks due to ingestion of and  dermal
 contact with contaminated soil.

 Potential risks to environmental receptors associated with the
 Site were identified in an Ecological Risk Assessment.  The
 results of the Ecological Risk Assessment indicated  that
 significant risk at the Site existed for various species
 including the robin,  woodcock nestlings,  red fox and mink, due to
 exposure to sediment and soil containing lead at concentrations
 greater than 500 ppm.   Based upon these findings, EPA concluded
 that a remedial action  objective for lead in soil and stream
 sediment of 500 ppm is  adequately protective of  ecological
 receptors.   Furthermore,  the 500 ppm remedial action objective is
 consistent with EPA OSWER Directive  #9355.4-02 which recommends a
 soil cleanup level  of 500 to 1000  ppm for protection of human
 health at residential sites.

 On July 8,  1994,  EPA issued the  Operable  Unit One Record of
 Decision (OU1  ROD).  The  OU1 ROD called for:  excavation of all
 soil contaminated with  lead above  the remedial action  objective
 of_500 ppm,  on-site  treatment  via  solidification/stabilization of
 soil classified as  hazardous under the  Resource  Conservation and
 Recovery Act,  and disposal  of  the  treated soil along with non-
 hazardous  soil  in a  landfill to  be constructed on the  Site;
 removal  of  contaminated stream sediments  above 500 ppm of lead
 from the East  Stream and  drainage  channel north  of Route 130 and
 treatment/disposal of the sediment in a manner similar to that
 described  for  soil; and extraction and  treatment of contaminated
 groundwater with  direct discharge of the  treated groundwater to
 the  Delaware River.

 On June  10, 1996, EPA entered  into an AOC with five PRPs that
provided for the  design of  the OU1 remedy.  On January 13, 1997,
 the  above AOC was modified  to provide for the PRPs'  maintenance,
with repair or  replacement  if necessary, of silt fencing
 installed along the West  Stream.  The' silt fencing has been
installed to minimize further migration of Site-related
contamination until the OU1  remedy is implemented.

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 Upon entering into  the AOC,  the  PRPs initiated OU1 remedial
 design  activities.   These  activities have included soil and
 groundwater  sampling to better define the extent of
 contamination.   In  addition, groundwater capture zone modeling
 will be conducted in order to ensure that the remedy will provide
 for  the complete capture of  Site-related groundwater
 contamination.

 On January 28,  1998,  EPA initiated negotiations with NL and four
 PRPs who sent lead-bearing material to the Site for
 implementation of the OU1  remedy and completion of Phase V of the
 Removal Action initiated by  EPA  in the West Stream.  Ultimately,
 in June 1998,  six PRPs signed a Consent Decree which memorialized
 their agreement  to  undertake these actions.  The Consent Decree
 was  entered  as  an order of the United States District Court for
 the  District of  New Jersey on April 1, 1999.

 Description  of  the  Significant Difference Between the July 1994
 ROD  and the  Modified Remedy

 The  selected remedy,  as presented in the OU1 ROD, addresses
 contaminated soil,  stream  sediment and groundwater at the Site.
 This BSD describes  a change  in the remedial approach for soil and
 sediment  only.   The  cleanup of contaminated groundwater will be
 conducted as described in  the July 1994 OU1 ROD.

 Based upon the evaluation  of alternatives conducted as part of
 the  OU1  FS prior to  issuance of the OU1 ROD, EPA determined that
 disposal  of  soil and sediment off-site was not as feasible as on-
 site  disposal.   At  that time, EPA concluded that off-site
 disposal  of  the  soil  and sediment would not be cost-effective.
 Cost  estimates provided in the OU1 ROD for remedial alternatives
 involving on-site and off-site treatment and disposal of soil and
 sediment  indicated  that it would cost $9,359,850 more for off-
 site  treatment and disposal of soil and sediment.  However, an
 evaluation of disposal options conducted by the PRPs during
performance  of the OU1 remedial design indicated that,  due to the
 elimination  of solid  waste flow control restrictions in New
Jersey,  and  the  resulting  increase in competition between Solid
Waste Disposal Facilities,  the excavated soil and sediment can be
disposed of  off-site  at a  cost that is competitive with on-site
disposal.  On-site treatment with off-site disposal of the site-
related soil and sediment  is currently estimated to cost $789,800
more  than on-site treatment with on-site disposal,  which
represents only a 4.2% increase in the estimated cost of the OU1
remedy.   Furthermore, off-site disposal of the soil and sediment
can be implemented more quickly than on-site disposal.   The time
to effectuate the off-site disposal remedy is estimated to be
between six  to twelve months, while the on-site remedy may take
up to 18 months  longer to  implement,  due to the requirement to
obtain all required state approvals for construction of the
landfill and the additional time necessary to construct the

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 landfill.   In addition,  local ordinances  concerning  the  setback
 of the landfill from the property line may further complicate  the
 design of  the on-site landfill.   Finally,  removing the soil  and
 sediment from the Site precludes  the need for  long-term
 monitoring of an on-site landfill,  which  would be required for
 the on-site disposal option.

 Although the remedy selected  in the OU1 ROD involving the on-site
 disposal of excavated soil  and sediment continues to be  a
 protective,  cost-effective  and implementable method  of addressing
 this media,  EPA is issuing  this BSD to notify  the public that,
 based upon information recently obtained  by EPA, the excavation
 of contaminated soil and sediment,  on-site treatment through
 solidification/stabilization  of hazardous soil and sediment, and
 off-site disposal of all excavated  material is more  appropriate
 based upon comparable protectiveness and  cost, and a shorter
 implementation time.

 SUPPORT AGENCY COMMENTS

 NJDEP did  not concur with the remedy selected  in the GUI ROD.
 NJDEP determined that, pursuant to  State  law,  environmental  use
 restrictions would be required for  the Site, unless  soil was
 cleaned up to the State  of  New Jersey's 100 ppm residential  soil
 cleanup criterion for lead.   In addition,  NJDEP believed that  the
 OU1  remedy did not address  off-site soil  appropriately,  because
 it did not provide for the  cleanup  of these soils to the 100 ppm
 residential  soil cleanup criterion.

 Subsequent to issuance of the OU1 ROD,  the  State of  New  Jersey's
 residential  soil cleanup criterion  for lead was revised  from 100
 ppm  to 400 ppm.   NJDEP has  informed EPA that a Deed  Notice is
 required for the Site pursuant to the Brownfield and Contaminated
 Site  Remediation Act,  N.J.S.A. 58:10B-1 (formerly the Hazardous
 Site  Discharge  Contamination  Act),  if soil  is  not remediated to
 the 400  ppm  residential  soil  cleanup  criterion for lead.

 PUBLIC PARTICIPATION ACTIVITIES

 In accordance with the NCP, a formal  public comment period is not
 required when issuing an BSD.  However, as  required by CERCLA,
 EPA published a  notice of this BSD  in Today's  Sunbeam,  a local
 newspaper.

 This BSD will be  incorporated into  the Administrative Record
maintained for the Site  in accordance with  Section 300.825(a)(2)
of the NCP.  The Administrative Record  is.available  for  review
 during business  hours  at  the  Penns  Grove Carney's Point  Public
Library, 222 South Broad Street,  Penns Grove, New Jersey 08069
 and at EPA Region  II,  Superfund Record  Center,  290 Broadway,  18th
 Floor, New York, New  York 10007-1866.

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        AFFIRMATION OF  STATUTORY DETERMINATIONS




                    fcth ?h?hgS  that ha^ been.made to  the  selected
*       ob-iP<-i--iro fn-r-~~-\~~x	  "~"•""""*'  J-ilv-J-u"J-"a "is 500 ppm cleanut
\       elective for lead  remains protective of human health and

                  it. «««„„,, „„  „+*—  residential or industrial future use
        appropriate to

        signed,  and is
       Jeanne

       Regionai^dministf^ator

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