BFF project activities are being conducted in accordance with the Resource Conservation and Recovery Act (RCRA), a federal regulation outlining the control of hazardous waste from “cradle-to-grave,” including the generation, transportation, treatment, storage, and disposal of hazardous waste. Oversight authority has been delegated from the Environmental Protection Agency, a federal agency, to the New Mexico Environment Department, a state agency.
In general, the RCRA regulatory framework being followed for this project includes the traditional corrective action components: initial site assessment, site characterization, interim actions, evaluation of remedial alternatives, and remedy implementation.
Initial Site Assessment: This step involves collecting information about site conditions, releases, potential releases, and exposure pathways to determine if a cleanup is needed and to identify areas of potential concern. Initial site assessment for this project began with identifying the fuel leak and conducting investigation activities from 1999 through 2007.
Site Characterization: Characterization to determine the nature and extent of contamination at a site and to collect the information needed to support selection and implementation of appropriate remedies needs to be done.
For this project, this refers to completing the characterization of contamination in the groundwater and Vadose zone to determine its nature and extent. The document summarizing these activities and conclusions is called a RCRA Facility Investigation Report and is submitted to the NMED for approval. For this project, a RCRA Facility Investigation Report will be submitted for both the groundwater and Vadose zone.
Interim actions allow for early treatment and remediation of ongoing risks to human health and the environment while completing the RCRA Facility Investigation Report and Corrective Measure Evaluation. Interim actions to date include:
- Contaminated soil (4,822 tons) above screening levels, was excavated in phases beginning in 1999 with the last excavation in 2015.
- In 2003, the Air Force installed the first soil vapor extraction (SVE) system on-base - between 2003 and 2015, SVE has removed 550,000 gallons of fuel.
- An additional 200,000 gallons of fuel and associated components have been removed through biodegradation (a process where naturally occurring bacteria breakdown contaminants into non-toxic products such as carbon dioxide, water, and ammonia).
- The interim measure pump and treat system installed in 2015 is designed to capture and treat the EDB in groundwater that has migrated off-base.
- As of 27 January 2016, approximately 19.4 million gallons of groundwater have been pumped from the off-base groundwater contaminant plume and treated to remove 8,590 milligrams (mg) of EDB.
Results from interim measures (e.g. system operation) are used in the evaluation of remediation technologies for identification of a final remedy. It is important to remember that the interim measures are not end points of remediation but are used to determine the final remedy approach.
Remedy Implementation: This phase involves detailed remedy design, construction, implementation and completion. It is during this phase the “final” remedy is put in place and is operational so as to address the contamination. There are regular evaluations to ensure the remediation approach is still meeting remediation objectives.