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PROJECT
PROFILES:
Superfund Site Cleanup in
Pennsylvania
Remediation of the first
Superfund site in Pennsylvania was designed and implemented by
RT Environmental Services, Inc. (RT) and considered by the
U.S. Environmental Protection Agency to be a "fine example of
the progress that can be made when government and the business
community work together to clean up the environment."
RT provided a two part solution-
a groundwater recovery and treatment system and remediation of
a landfill operable unit.
The groundwater treatment system
involved hydrogeological investigation work in a semi-karst
limestone aquifer, and design and construction of a 160 gallon
per minute groundwater recovery and treatment plant. Compounds
treated include benzene, toluene, xylene, ethylbenzene,
dichloropro-pane and other industrial solvent-type compounds.
The landfill work consisted of
design and installation of landfill leachate collection and
capping systems. A bentonite clay composite cap was installed
to prevent further migration of contaminants into the
groundwater. In addition, special projects were completed to
remove oil contaminated soils, containers of ether and
drums.
Project Team
Approach
RT assigned a small dedicated team of
project engineers and construction managers to oversee all
phases of the project and insure accountability and a focus on
project success. Project risk was reduced by obtaining
performance guarantees for treatment process equipment from
major equipment vendors.
Solution-oriented
Engineering
For the groundwater system, treatment
equipment was pre-selected at the start of design so that most
engineering efforts concerned installation of the equipment in
a pre-engineered building. Specific features include:
- Programmable controller oversight
instrumentation system to continuously monitor key plant
functions, summon operator assistance, and take action to
avoid spills automatically.
- Continuous treatment process quality
monitoring of toxic gas in pump tanks.
- Volatile extraction system for
control of subsurface toxic gases in subsurface limestone
caverns.
- Pulse groundwater recovery techniques
to avoid treating large quantities of mildly contaminated
groundwater resulting in lower groundwater pumping costs and
maximum treatment removal efficiency.
For the landfill operable unit, use of
bentonite clay material and adding a leachate collection
system minimized groundwater contamination. In addition,
septic systems were closed, sewers were connected, and the
western portion of the site was repaved. Also the water main
was isolated with a liner system thereby avoiding the
necessity of moving the water main and saving $3
million.
Adherence to Budget and
Schedule
The
project spanned a three year period, from mid-1989 to mid-1992
and was completed within budget and ahead of schedule. Ongoing
operation and maintenance costs for the system are a few cents
a gallon, evidence of RT's commitment to cost-effective long
term solutions. In all, the two units were remediated for a
capital cost of $10 million, a modest cost for two Superfund
units at a site with complicated hydrogeology.
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