The Interstate Technology & Regulatory Council (ITRC) In Situ Bioremediation (ISB) team is finalizing a technical guidance document that presents information necessary to evaluate a systematic approach to ISB for chlorinated ethane DNAPLs. ISB systems usually involve modifications of the natural subsurface environment, to accelerate biodegradation. ISB technologies for the remediation of chlorinated ethane DNAPLs are in the developmental stage. Few applications have been completed. A primary purpose of this presentation is to provide sufficient technical and regulatory information to make informed decisions on whether to proceed with ISB systems. Understanding the fate and transport, properties, and limitations are essential to implement ISB systems addressing chlorinated ethane DNAPLs. Knowing a site's history and general information on the pervasiveness and properties of chlorinated ethane DNAPLs in addition to the hydro geologic environment and geochemistry are essential quantities to evaluate a systematic approach to ISB in groundwater. This document also provides explanation and insight into the types of information that will likely be required by regulators.