Engineering Services Best Practices and Blog

AUL at Environmental Emergency Response Companies

Posted by Rebecca McDaniel

By Jeremy Brandl, Engineering Technician

Activity and Use Limitations (AULs) are legal restrictions used in the context of the Massachusetts Contingency Plan (MCP) to limit future exposure to contaminants remaining in soil at a disposal site. An AUL on a property will alert future property owners that the property they will be occupying has potential risk for exposure.

“The purpose of an Activity and Use Limitation is to narrow the scope of exposure assumptions used to characterize risks to human health from a release pursuant to 310 CMR 40.0900, by specifying activities and uses that are prohibited and allowed at the disposal site in the future.”

A way to determine risk is by completing the risk characterization process. In Massachusetts, the guidelines in the MCP determines when an AUL is needed to eliminate potential exposure pathways. The AUL is necessary for the continued validity of a Response Action Outcome Statement (RAO) to ensure that the disposal site presents No Significant Risk to human health or the environment over time.

Elements of an AUL:

• written restriction, providing notice

• imposed by the land owner (DEP approval not required, but DEP can enforce)

• recorded at the Registry of Deeds (or Land Court)

• restricts future uses and allows permitted uses

• to prevent exposure to remaining oil or hazardous materials (OHM)

• largely used for soil contamination (for groundwater: to eliminate an existing private well, O + M of venting system or vapor barrier)

• goal/benefit: to reduce response actions (and costs) while maintaining protection (e.g., Brownfields redevelopment)

A detailed AUL guidance document may be found on the Mass DEP website ( If you should have any questions or require more information on this topic, please contact Triumvirate's Site Assessment and Remediation Division for more information. We have experienced Licensed Site Professionals and Environmental Engineers ready to answer your questions.

Tags: Massachusetts Contingency Plan, MCP, disposal of contaminated soil, Environmental Engineers, AULs, Activity and Use Limitations, RAO, AUL, What is an AUL?, What are AULs?, contaminants, soil disposal, disposal of soil, contaminated soil disposal, 310 CMR 40.0900, AUL guidance document, Mass DEP, Triumvirate's Site Assessment and Remediation