In Situ Stabilization & Solidification
	Team Leader Wilmer Reyes 302-395-2630 wilmer.reyes@state.de.us

Stabilization and solidification involve the mixing of specialized additives or reagents with waste materials to physically or chemically reduce the solubility or mobility of contaminants in the environmental matrix. The term "stabilization" is used to describe techniques that chemically modify the contaminant to form a less soluble, mobile, or toxic form without necessarily changing the physical characteristics of the waste. The term "solidification" refers to a technique for changing the physical form of the waste to produce a solid structure in which the contaminant is mechanically trapped.

Although in situ stabilization and solidification (ISS) technologies offer promise as a cost-effective means to remediate highly contaminated sites, their use is hampered by several barriers:

• Performance measures to assess ISS remediation technologies are not readily available.
• Regulatory approval processes vary from one EPA region to another, from state to state, and even within the same state.
• Inconsistencies and lack of standard approaches result in case-by-case development of acceptable criteria, which is very costly and time-consuming.

Therefore, the goal of the ISS Team is to develop a technical and regulatory document and training to address the use of ISS technologies. Guidance will provide a more consistent approach to evaluating the applicability and effectiveness of ISS technologies. Additionally, the team’s work will provide parties conducting cleanups with assurance that the assessment measures undertaken for ISS follow an approach recognized by regulators nationwide. The availability of this guidance and training will save regulatory agencies and responsible parties time and cost in the evaluation and implementation of ISS technologies.