Masada Custom Builders: 1500 South Front Street, Philadelphia

The Site is located at 1500 South Front Street at the southwest corner of S. Front Street and Dickinson Street. The site had been developed for various commercial uses, including a lumber yard, during the 20th century, but by the 1980s had become vacant and unused.
Investigations at the site in March 2004 had identified exceedences of the PADEP health standards in soil and groundwater. REPSG reviewed the findings of the earlier investigation and hypothesized that the presence of low levels of lead, zinc and arsenic in the subsurface, as well as low levels of lead in the groundwater may be indicative of the presence of “historic fill” located at the Site, and not as the result of direct releases to the subsurface of these compounds.

Utilizing the approved statistical methodologies of Act 2, REPSG conducted a “randomized sequential sampling” of the soil to characterize conditions in the subsurface and determine the true environmental risk at the site. The fill characterization data was evaluated to determine if the ‘true’ site median concentrations of lead, arsenic, and zinc were below the applicable SHS. This evaluation was made by applying the statistical test known as the 75%/10x rule. Specifically, the rule requires 75% of the samples collected for demonstration of attainment be below SHS and no single sample result exceeds the risk-based standard by more than ten times.

It was verified that at least 75% of samples tested were below SHS and no single sample exhibited a concentration more than twice the cleanup standard. Based on the application of the 75%/10x rule, the true site median concentration of lead, arsenic, and zinc was verified to be below the applicable SHS. Attainment of Statewide Health Standard for these analytes in the on-site fill material had been demonstrated.

Current Status

Following submission of a Final Report by REPSG to the PADEP in October 2004, the Site received approval from the PADEP in November 2004 for remediation at the site to the provisions of the Statewide Health Standard (SHS) under Act 2. The site has since been redeveloped with 16 new residential units.