How to Incorporate Risks of Extreme Weather Events and Natural Hazards in an ABCA

Incorporating Risks of Extreme Weather Events and Natural Hazards in an Analysis of Brownfield Cleanup Alternatives (ABCA) to Support Grant-funded activities

An Analysis of Brownfield Cleanup Alternatives (ABCA) is a report that compares site cleanup options based on site-specific conditions, effectiveness, feasibility and cost. Typically, an ABCA includes descriptions of the background and current conditions of the site (i.e., maps, previous uses, assessment findings, reuse goals, etc.), applicable regulations and cleanup standards, an evaluation of cleanup alternatives and a recommended remedial action. The evaluation of cleanup alternatives outlined in the ABCA is based on the effectiveness, ease of implementation and cost of each remedial action.

EPA Brownfields Cleanup Grant applicants must submit a draft ABCA to meet site eligibility requirements. A publicly reviewed and finalized ABCA or equivalent state Brownfields program document must be in place before EPA funded on-site cleanup activities can begin. Preparing and updating an ABCA, or equivalent state Brownfields program document, is an eligible expense under all Brownfields Multipurpose, Assessment, RLF and Cleanup Grants.

Why do risks of extreme weather events and natural hazards need to be included in the ABCA?

Current and forecasted changes in the frequency and intensity of extreme weather events and natural hazards may create risks to the long-term effectiveness of a site remedy and how the site can be safely reused over time. Evaluating these conditions before and during site cleanup and reuse planning is important to protect human health and the environment.

An ABCA, or the equivalent alternative analysis document required by a state voluntary cleanup program, is the best opportunity to efficiently document whether each cleanup approach under consideration will withstand anticipated conditions over the long term to remain protective.

To ensure that brownfield site cleanups remain effective, EPA requires that when grant recipients prepare an ABCA, or equivalent state Brownfield program document, the ABCA must consider “the resilience of the remedial options to address potential adverse impacts caused by extreme weather events and natural hazards (e.g., sea level rise, drought, increased frequency and intensity of flooding, etc.).”

Brownfield Grant recipients can follow the two steps below to assist with accounting for extreme weather and natural hazards in the ABCA report. This guidance is optional and its use is not required.

Risks of extreme weather events

Examples of risks include, but are not limited to:

Increased/decreased temperatures
Sea level rise
Increased salt-water intrusion
Increased storm surge
Increased risk of wildfire
Coastal subsidence of land
Changing dates for ground thaw/freezing
Changing environmental/ecological zones
Changing flood zones
Heat island impacts
Higher/lower groundwater tables
Extreme weather events (e.g., storms of unusual intensity, increased frequency and intensity of localized flooding events)
Increased/decreased precipitation (resulting in flooding and/or drought)

Step 1: Identify Current and Forecasted Risks of Extreme Weather and Natural Hazards

Review authoritative resource(s) to identify observed and potential risk conditions and any existing resiliency or hazard mitigation planning that covers the same area. Examples of federal resources:
Determine site-specific risk factors based on known site conditions and natural hazard risks identified above. Some examples of known site conditions include proximity to the ocean, property affected by a revised FEMA flood plain map, infrastructure vulnerabilities, vulnerability of soil type due to moisture and hydraulic changes, ground and surface drinking water vulnerabilities, potential exposure of contaminated sediments during drought conditions, etc.

Local data and resources may be obtained from regional planning or county governments, municipalities, or EPA Regional Offices.

Step 2: Incorporate identified risks of extreme weather and natural hazards into the ABCA

Evaluate and document the extent to which current and forecasted conditions pose a risk to the effectiveness of each site cleanup alternative. These risk factors need to be considered in the effectiveness portion of the ABCA.
- Include in your effectiveness evaluation how well each alternative can accommodate the identified risk factors. Remember to consider all stages of the cleanup and long-term reuse of the site. For example:
  - Will increased flooding events compromise a site with an engineered cap?
  - Will sea level rise or salt-water intrusion reduce the ability of vegetation to control erosion?
  - Will a suggested phytotechnology approach remain protective during periods of drought?
- Consider how to optimize the preferred cleanup alternative with best practices from resilient and green remediation standards, vulnerability assessments and any resilient and sustainable site reuse planning or regulations that may be in place. See the best practice guidance linked below in the Learn more box.

Note: EPA does not expect grant recipients to generate new site-specific data to complete this analysis. Through the ABCA, grant recipients must demonstrate they have reviewed available current and authoritative information for the assessment and cleanup analysis. The level of analysis expected depends on the proposed reuse and site location, the complexity of the project and the degree of risk involved given the feasible remedial options and targeted reuse of the site.