Response Action Outcome Statements (RAO) Statements are the endpoint of the site assessment and remediation process under the Massachusetts Contingency Plan (MCP).  It’s the point at which you say “there’s no risk – I’m done”.  As part of their proposed MCP revisions, the MassDEP is proposing to eliminate RAO Statements.  They’re not actually eliminating the endpoints.  They’re just considering changing the names and categories since RAO is not intuitive for many people (we agree).

The proposed new terms/categories are:

  • Permanent Solution with No Conditions
  • Temporary Solution
  • Permanent Solution with Conditions

Permanent Solutions with No Conditions will include sites where remaining contamination does not pose a risk to human health or the environment without limitation. That is, there is no risk to human health in the future regardless of what the property is used for (like a residence, school or day care) or how accessible the contamination becomes (for example if pavement overlying contamination is removed).

Temporary Solutions will include sites where a Permanent Solution is not currently feasible because contamination can’t be readily cleaned up or it can’t be cleaned up in a reasonably timely manner to allow a Permanent Solution to be achieved.  This may include sites where the contamination poses a risk but it isn’t accessible (for example beneath a building) or the type and extent of the release precludes achieving a Permanent Solution any time soon (for example a large chlorinated solvent release).

Permanent Solution with Conditions will include sites where remaining contamination does not pose a risk to human health or the environment but… (you guessed it) there are some conditions that apply to the closure.  This category includes closures with Activity and Use Limitations (deed restrictions or “AULs”), as well as other specific site conditions for which AULs are not required but the site conditions warrant consideration of the information in the closure documentation to ensure there is no risk to human health in the future.  These conditions include:

  • residual groundwater contamination at undeveloped sites that may pose a potential risk of vapor intrusion into buildings constructed in the future;
  • the presence of soils at the site with contamination attributable to “historic fill;”
  • elevated contamination remaining under roadways; and
  • “best management practices” to be taken for gardening at a site with residual contamination.

This is a new concept wherein the category of closure and the associated documentation is deemed sufficiently protective of public health without the added notice provided by an  AUL.  The thinking is that parties involved with the property in the future will see the category of closure, understand there are conditions related to the closure and educate themselves about what those conditions are and how to protect human health.

The MassDEP is accepting public comments on these proposed changes to the Massachusetts Contingency Plan through Friday May 17, 2013.

If you’re wondering how the proposed changes may affect you, please contact Omni Environmental Group’s Licensed Site Professional (LSP) at 978-256-6766 or  Read more about our LSP services and a summary of the proposed MCP revisions.

“An LSP Opinion” is an occasional feature here in the Omni Environmental Group blog.  We’ll talk about the Massachusetts Contingency Plan along with the roles and responsibilities of Licensed Site Professionals.