New EPA Guidance Cuts Prior Residential Soil Lead Levels in Half

The US Environmental Protection Agency (EPA) recently lowered the recommended regional screening level (RSL) and regional removal management level (RML) for lead-contaminated soil in areas where children live and play from 400 parts per million (ppm) to 200 ppm. EPA recommends using an even lower RSL of 100 ppm in areas with other sources of lead exposure, including lead water service lines and lead-based paint, and areas identified as non-attainment areas for lead emissions under the Clean Air Act.

The guidance applies to sites addressed under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA or Superfund) and Resource Conservation and Recovery Act (RCRA) Corrective Action facilities.

Key Takeaways

• Parties conducting CERCLA or RCRA Corrective Action responses at lead sites in residential areas should anticipate requirements to undertake additional investigations to determine whether further remedial action is necessary.
• The new guidance can trigger a reopener for Superfund and RCRA Corrective Action sites where lead remedies have already been completed or are underway.
• EPA has set aggressive goals to address sites where lead is a contaminant.
• Tools such as EPA’s EJScreen and available lead exposure data sets will be important factors in determining what screening level applies.
• The screening levels are not cleanup standards and are not considered in Hazard Ranking System (HRS) scoring used to identify and rank sites for the National Priorities List (NPL).

Background

EPA released the new guidance—Updated Residential Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action Facilities—on January 17. The guidance updates the two screening levels—RSLs and RMLs—used to determine whether further investigation or removal action is needed at a site to protect the health of individuals and nearby communities.

RSLs are conservative values used to identify contaminated media (i.e., air, water, or soil) that may require further study. RMLs are generic levels used to define areas, contaminants, and conditions that may warrant a removal action under CERCLA, such as providing alternative drinking water or hot-spot remediation.

EPA’s new screening levels update those established in two prior guidance documents that had been applied for more than three decades: Revised Interim Soil Lead Guidance for CERCLA Sites and RCRA Corrective Action Facilities (1994) and Clarification to the 1994 Revised Interim Soil Lead Guidance for CERCLA and RCRA Corrective Action Facilities (1998).

These prior guidance documents recommended screening levels based on 10 μg/dL as the 95th percentile target blood lead level, while the screening levels in the new guidance are based on 5 µg/dL or 3.5 µg/dL for the 95th percentile target blood lead level.

A key driver for the lower screening levels is the Centers for Disease Control and Prevention’s (CDC’s) new blood lead reference value used to identify children with high levels of exposure. The CDC lowered its reference value from 5 ug/dl to 3.5 ug/dl in 2021 to reflect the 97.5th percentile of blood lead level distribution in US children between one and five years old.

The new guidance reflects the first time EPA has applied these lower CDC values. EPA also explains in the new guidance that its application of these lower screening levels is warranted based on updated information that “demonstrates additional adverse health effects of lead exposure and at lower levels than previously known.”

Implications for Responsible Parties

The new guidance takes immediate effect and applies to all residential lead sites subject to CERCLA response and RCRA Corrective Action, including sites that have been previously addressed and/or removed from the NPL.

“Residential” sites include all areas where children have unrestricted access, including properties where children may live but also vacant lots in residential areas, schools, daycare facilities, community centers, playgrounds, parks, and other recreational areas.

As EPA acknowledges in the new guidance, a “significant number of residential properties could undergo evaluation and cleanup because of this guidance.” EPA regions will use the existing prioritization process to determine which sites should be evaluated and remediated.

The guidance has been released as a follow-up to EPA’s Final Strategy to Reduce Lead Exposures and Disparities in US Communities and its Federal Action Plan to Reduce Childhood Lead Exposures and Associated Health Impacts, which were emphasized in part of the Biden administration’s Executive Order on Advancing Racial Equity and Support for Underserved Communities Through the Federal Government.

The guidance was specifically listed as a milestone in EPA’s October 2022 strategy document for fiscal year 2023 as Goal 1, Objective C: Reduce Exposure to Lead in Soils. EPA has also stated that it would focus its cleanup efforts on communities with environmental justice concerns first, as these communities are typically exposed to lead from multiple sources, thereby underscoring the importance of environmental justice screening tools in cleanups going forward.

Site-Specific Considerations

It is important to note that the lower screening levels are not de facto cleanup standards, nor are they considered in HRS scoring to identify and rank sites for the NPL. As such, the impact of the lower screening levels on cleanup requirements will depend in large part on how the guidance is applied at specific sites.

As EPA notes in the guidance, “While this update will help EPA site teams make site-specific cleanup decisions to protect nearby communities, EPA makes cleanup decisions specific to each site, using site-specific factors, including risk factors and community input that can vary from site to site.”

Further, EPA is clear in the new guidance that cleanup levels should not be set at values below natural or anthropogenic background, consistent with its longstanding guidance, the Role of Background in the CERCLA Cleanup Program. Background levels of lead in many areas are well above the revised screening levels of 100 and 200 ppm, further emphasizing that the impact of the new guidance at a particular site will be influenced by site-specific factors.

While the new guidance goes into effect immediately, EPA welcomes feedback from the public through March 17, 2024. Feedback may be considered in any future updates to the guidance.