PB97-963130
EPA/541/R-97/094
January 1998
EPA Superfimd
Explanation of Significant Difference
for the Record of Decision:
Bendix Flight Systems Division
South Montrose, PA
11/22/1996
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EXPLANATION OF SIGNIFICANT DIFFERENCES
BENDIX FLIGHT SYSTEMS DIVISION SUPERFUND SITE
SOUTH MONTROSE, SUSQUEHANNA COUNTY, PENNSYLVANIA
A. Introduction
The Environmental Protection Agency, Region III (EPA) is issuing this Explanation of
Significant Differences (ESD), pursuant to its authority in Section 117(c) of the
Comprehensive Environmental Response, Compensation, and Liability Act of 1980, as
amended (CERCLA), 42 U.S.C. § 9617(c), and the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP), at 40 C.F.R. § 300.435(c)(2)(i), for the
September 30,1988, Record of Decision (ROD) (no. 197, Section III, in the Administrative
Record Index for the Site) issued for the Bendix Flight Systems Division Superfund Site
(Site) in South Montrose, Pennsylvania. EPA is the lead agency for the Site and the
Pennsylvania Department of Environmental Protection (PADEP) is the support agency.
EPA has identified an aspect of the Site remedy that is appropriate to change through
this ESD. EPA has determined that this change does not fundamentally alter the remedy
selected in the ROD with respect to scope, performance, or cost. This ESD will become
part of the administrative record file located in EPA Region III and the offices of the
Susquehanna Planning Commission at the addresses listed below in Section F.
B. Summary of Site History. Contamination Problems, and Selected Remedy
The Bendix Superfund Site is an active aircraft instrument manufacturing plant. From
1952 to 1978, solvents used in degreasing operations were disposed into the onsite
wastewater treatment system, into a series of earthen trenches and onto the ground
surrounding the plant. The disposal practices resulted in contamination of the soil and
groundwater, with chemicals including trichloroethylene ("TCE"), perchloroethylene
("PCE"), 1,1,1-trichloroethylene ("TCA"), vinyl chloride, benzene, and xylene (hereinafter
collectively referred to as "VOCs"). The contaminants are "hazardous substances" as
defined in Section 101(14) of CERCLA.
For a more detailed summary of site history, and contamination problems, see Sections
III (page 1) and V (page 2) of the ROD. For a description of the remedy as set forth in
the ROD, see Section XII (page 24).
C. Significant Differences: Rationale
Selected Remedy for the Contaminated Soil Areas.
There are two majors areas of VOC contaminated soils at the Site; the area to the
east of the Bendix plant, and the area to the west of the plant. The selected remedial
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alternative for the soils on the east side of the plant was excavation and mechanical
aeration, and for the soils on the west side of the plant the selected remedy was vacuum
extraction. One of the main reasons vacuum extraction was selected for the west side
of the plant was because there were numerous buried utilities in this area making soils
excavation and aeration (as selected for the east side) both hazardous and
environmentally inefficient. In 1991 a vacuum extraction and soil dewatering pilot study
was performed to assess the effectiveness of this technology and to gather information
for designing the site remedies. This study and other remedial work at the Site found
vacuum extraction to be technically and physically impractical due to the nature of the
soils in this area (glacial till). Furthermore, the impediments to excavation and soil
aeration, i.e. the buried utility lines, were removed by relocating them overhead.
Therefore, the reponsible party requested that the remedy be changed to provide for soil
excavation and aeration on the west side of the plant instead of vacuum extraction. EPA
has decided that it is appropriate to make this change. This BSD modifies the Record
of Decision; however, the attainment levels and levels of protection remain unchanged.
In summary, this ESD allows for the same remedial action (i.e mechanical soils aeration)
to occur for soils on the west side of the plant as was specified in the Record of Decision
for the east side of the plant.
D. Affirmation of Statutory Determinations
Considering the new information tr : has been developed and the changes that have
been made to the selected remedy, EPA believes that the remedy, as modified by this
ESD, remains protective of human health and the environment, complies with Federal
and State requirements that are applicable or relevant and appropriate to this remedial
action, and is cost-effective. In addition, the revised remedy utilizes permanent solutions
and alternative treatment technologies to the maximum extent practicable for this Site.
E. Support Agency Comments
The above changes to the remedy have been coordinated with representatives of
PADEP pursuant to 40 C.F.R. § 300.435(c)(2)(i). PADEP verbally concurred on
November 13, 1995 with changes to the selected remedy as described in this ESD.
F. Public Participation Activities
As required by 40 C.F.R.§ 300.435(c)(2)(i), notice of this ESD will be published in the
local newspaper. This ESD is part of the administrative record file and is available for
review at the two locations identified below:
AR30168I
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E. Support Agency Comments
The above changes to the remedy have been coordinated with
representatives of PADEP pursuant to 40 C.F.R. S300.435(c)(2)(i).
PADEP verbally concurred on November 13, 1995 with changes to the
selected remedy as described in this ESD.
F. Public Participation Activities
As required by 40 C.F.R.S 300.435(c)(2)(i), notice of this
ESD will be published in the local newspaper. This ESD is part
of the administrative record file and is available for review at
the two locations identified below:
United States Environmental Protection Agency
Region III
841 Chestnut Building
Philadelphia, Pennsylvania 19107
(215) 597-3037
Hours: 8:30 a.m. to 5:00 p.m.
Monday through Friday
Susquehanna County Planning Commission
31 Public Avenue
Montrose, PA 18801
(717) 278-4600
Hours: 8:00 a.m. to 5:00 p.m.
Monday through Friday
'i
.e&t-^.
ate Thomas C. Vol/tagcpip, Djj?e'ctor
Hazardous WasxaJlM:ngg^ment Division
AR3GI682
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