M&A staff not only provided oversight for the latter stages of this remedial investigation, but we helped develop the technical and regulatory requirements for selecting the final regional groundwater remedy. M&A staff members were responsible for:

• Strategic remedial planning
• Preparation of a site-wide feasibility study (FS) and remedial action plan (RAP)
• Preparation of interim FS’s and RAPs for individual operable units
• Frequent interaction and negotiation with the regulatory community and other stakeholders

Recent evaluations and modeling showed that the regional remedy effectively controls plume migration and protects the threatened water supply wells.

Starting in 2008, we began pilot-testing an in-situ bioremediation system to treat perchlorate in the primary source area. This work had several components: we designed and tested the extraction and injection wells, conducted tracer testing, modeled groundwater flow and contaminant transport, and implemented compliance monitoring and reporting programs.

After more than 2 years of operation, the system has proven effective at economically controlling the source area. Additional evaluations are ongoing to explore the cost-benefit of expanding system operations to reduce lifetime remedy costs.

As part of the FS, M&A developed a three-dimensional flow-and-transport model using MODFLOW / MT3D. We also conducted vadose-zone modeling to assess source areas.

M&A oversees the site-wide monitoring program. We also coordinate with a diverse group of stakeholders and interface with regulatory personnel from the State of California’s Department of Toxic Substances Control and Regional Water Quality Control Board. In addition, we have secured waste-discharge permits and ensured compliance with these permits.

M&A provides technical support for mediation between our client and other stakeholders.