[SRRA]: Updated Dilution-Attenuation Factor, Soil Screening Levels and Leachate Criteria for the Impact to Ground Water Soil Remediation Standards

The default Dilution-Attenuation Factor (DAF) used for calculating Impact to Ground Water Soil Remediation Standards has been updated from its previous value of 13 to a new value of 20. This change results in new default impact to ground water soil screening levels, which are listed in an updated Soil-Water Partition Equation guidance document. The new DAF also affects the default Leachate Criteria, which are used in conjunction with the Synthetic Precipitation Leaching Procedure and the SESOIL simulation model. The new values for the Leachate Criteria are listed in an updated Synthetic Precipitation Leaching Procedure guidance document. An updated Dilution-Attenuation Factor guidance document explains the basis of the new DAF value. The updated guidance documents, along with new versions of the EXCEL spreadsheets for the soil-water partition equation, synthetic precipitation leaching procedure, and the dilution-attenuation factor have been posted on the soil remediation standards website:

https://www.nj.gov/dep/srp/guidance/rs/

The new spreadsheets now include the ability to calculate impact to ground water soil remediation standards for new (unlisted) chemicals.

SRP Site Remediation Reform Act (SRRA) Web site: https://www.nj.gov/dep/srp/srra/