Superfund Site Cleanup in Pennsylvania

PROJECT PROFILES:

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.