A Toolkit for Evaluating Climate Change Impacts to Chapter 21E Sites Under the Amendments to the Massachusetts Contingency Plan

On September 1, 2023, MassDEP issued final amendments to the Massachusetts Contingency Plan (“MCP”), the regulations governing the cleanup of releases of hazardous material and oil spills at contaminated properties. The MCP amendments, which will take effect on March 1, 2024, will now require the consideration of foreseeable climate change impacts and how they may affect the status of completed remediation actions.

The changes to the regulatory text are minor but they will significantly affect the performance of response actions under the MCP. For example, the amendments revise the definition of a Conceptual Site Model (“CSM”) in 310 CMR 40.0006(12) so that licensed site professionals (“LSPs”) must begin “assessing current and foreseeable future site characteristics and risk” when developing the CSM framework (new language in bold). Also, the amendments add new language to the Response Action Performance Standard in 310 CMR 40.0191 to require the “use of accurate and up-to-date methods, models, standards and practices, equipment and technologies” in conducting response actions and to expressly include the consideration of “response actions that incorporate climate change resilience to the extent practicable and consistent with response action requirements” when performing cleanups under the MCP. Finally, the amendments expressly incorporate climate change considerations into the definition of a “foreseeable period of time” in the context of a Permanent Solution in 310 CMR 40.1005(1):

A Permanent Solution shall ensure a level of control of each identified substance of concern at a site or in the surrounding environment such that no such substance of concern shall present a significant risk of harm to health, safety, public welfare or the environment during any foreseeable period of time, considering existing site conditions and reasonably foreseeable future changes in site conditions, including anticipated impacts associated with climate change.

Far from a major overhaul of the MCP, the amendments are a targeted integration of climate change considerations into the existing structure of the regulations.

The Licensed Site Professional Association (“LSPA”), the trade association of the scientists, engineers, and public health specialists licensed by the Commonwealth to oversee the assessment and cleanup under the MCP, has been spearheading the effort to ensure a smooth implementation of the new climate change amendments. The LSPA has developed a toolkit for LSPs to assess the vulnerability of a contaminated site, evaluate potential impacts to contaminants of concern, and consider site-specific options to mitigate any impacts.

Vulnerability is a function of a site’s exposure to climate change impacts—in particular, changes in precipitation, temperature, sea level rise, and extreme weather events, the major impacts associated with climate change as defined in the Commonwealth’s 2018 State Hazard Mitigation and Climate Adaptation Plan (“SHMCAP”)—and the risks to contaminated sites associated with these impacts. The LSPA toolkit includes a climate change risk evaluation flow chart, a vulnerability assessment checklist, case studies, and technical resources for LSPs to use in determining whether a particular contaminated site requires further response actions after having achieved a Permanent Solution and site closure. It should prove to be an invaluable resource to LSPs as they navigate the future concerns of property owners, site operators, and other parties involved with contaminated sites.