The Monroe solar farm is a privately owned 35-acre site which historically operated as a clay mine from the 1950’s until the early 2000’s.  Backfilling of the mine occurred concurrent with mining starting in the 1970’s, with the majority of backfilling operations taking place prior to modern NJDEP clean fill guidance and standards.  RT completed a Preliminary Assessment and Site Investigation, which confirmed the presence of historic fill at the site, and a small, previously closed coal ash landfill.  Following consultation with NJDEP, RT completed a Remedial Investigation to determine whether or not backfill materials constituted an unpermitted solid waste facility.  The investigation evaluated fill materials up to 45 feet below ground surface to the mined elevations.  RT concluded, and NJDEP concurred, that the site was backfilled with historic fill and could proceed with remediation under the Contaminated Site Remediation and Redevelopment Program (formerly the Site Remediation Program).

Remediation of the site included backfilling of the mine with approved alternative fill, installation of a clean soil cap, and installation of stormwater management facilities consisting of piping and a retention basin.  Capping of the site was completed concurrent with the construction of a 15-Megawatt solar array facility.  Development of the solar farm was made possible in part by RT, who on behalf of the solar developer, obtained approval from the NJ Board of Public Utilities to receive payment for solar generation through the state’s Clean Energy Program, which incentivizes solar development on historic fill and landfill sites.  After the project was complete, RT prepared a Remedial Action Permit application, and once approved by NJDEP, the LSRP issued a Response Action Outcome statement.  RT has completed the permit-required biennial certification inspections, and has found the cap remains protective of public and environmental health and safety.  The solar farm is anticipated to be in operation for up to 25 years.