Description of Work:
This project consisted of constructing a HDPE Curtain Wall and Underdrain system. The purpose for the HDPE Curtain Wall is to eliminate the off-site migration of NAPL from the Sun Company Philadelphia Refinery into the Schuykill River.
A 2,100-foot HDPE Curtain Wall was installed along the river boundary, tying into an existing sheet pile wall on both ends. The wall varies from approximately 15 feet deep at the northern end to about 23 feet deep at the southern end, running approximately 10 to 12 feet inland of an existing wooden bulkhead. The curtain wall was successfully installed through a slurry-supported trench.
A 3,050 foot interception/collection trench was installed parallel to the HDPE Curtain Wall, continuing beyond the curtain wall on the southern end. The depth of the trench varies from approximately 10 to 13 feet deep. An 8-inch diameter perforated HDPE Header pipe was placed in the trench to convey groundwater and product to two sumps. The trench is 21 inches wide and contains aggregate to approximately 3 feet below ground surface. This work was accomplished using the Bio-Polymer slurry drainage trench (BP Drain) technique.
Upon completion of the original contract work, Geo-Solutions was retained to install an additional collection trench in the PGW area of the refinery. The collection trench was approximately 800 foot long, ranging in depth from 20 to 24 feet deep. A 6-inch diameter perforated HDPE pipe was placed in the trench to convey groundwater and product to a single sump. The trench is 21 inches wide, with the lower half of the trench being backfilled with aggregate. This work was also accomplished using the Bio-Polymer slurry drainage trench (BP Drain) technique.