Remediation of Former Shell Station
Client Name: Remediation of Former Shell Station
- Use of a slide rail shoring system
- Business remained open during remediation
- Removal of all site utilites for remediation
- Restoration of utilities during backfilling
- Excavation and management of 700 tons of contaminated soil
This site was a former Shell Service Station located in Watertown, NY, and required removal of petroleum impacts associated with the site's former use as a fuel services station. Located on the site is one 1,100 square foot structure that currently operates as a Trailways bus station. The subsurface impacts were isolated to the front part of the property between the building and the sidewalk. The proposed excavation area contained water and sewer subsurface utilities, several unidentified pipes, and had an overhead electric line that crossed the area. As part of the pre-excavation project investigation, the subsurface utilities were surveyed and identified utilizing ground penetrating radar (GPR). The subsurface pipes identified during the GPR survey were located utilizing soft dig excavation methods to confirm location and depth. Once the locations of the subsurface utilities were confirmed, 20 subsurface soil boring were advanced at the site to a depth of 15 feet below grade. All soil boring locations were pre-cleared using soft dig methods to a depth of 4 feet below grade.
Prior to the start of the intrusive excavation activities, SES replaced the existing water, sewer, and electric services to the building with temporary facilities. The temporary services that provided to the Trailways business were a portable generator, sanitary toilet trailer, and portable water cooler. SES then had the overhead electric service removed and capped the subsurface utilities at the limits of the excavation area The excavation was conducted in cells utilizing a slide rail shoring system. The excavation depth ranged from 10 feet below grade to 12 feet below grade. Impacted soils were excavated, live loaded into trucks, and transported off-site for disposal via waste manifests at a Shell approved facility. ORC pellets were spread across the excavation bottom and clean crushed stone was placed into the excavation in one-foot lifts that were compacted with a remote vibratory roller. Once the cell was backfilled the excavation moved to the next cell. When the backfilling activities were complete, the subsurface and overhead utilities were restored to the Trailways building and the temporary services were removed. The parking lot impacted by the construction activities was paved, and the parking spaces were repainted.