Get Full Government Meeting Transcripts, Videos, & Alerts Forever!
Get email alerts on the Soil Reuse Case Study topic
No spam. Unsubscribe anytime.
South Coast Rail project reused about 93% of excavated materials, MassDEP presenters say
Summary
Presenters described the MBTA South Coast Rail program as a case study in large-scale beneficial soil reuse: about 390,000 cubic yards of material were excavated and roughly 93% (~360,000 cu yd) was reused on the project through early planning, material tracking and MassDEP coordination.
MassDEP advisory committee members heard a case study Tuesday on how the MBTA South Coast Rail program substantially minimized off-site disposal through planned reuse of excavated materials.
Michael Stiller of AECOM, presenting on behalf of MBTA partners and designers, said the program excavated roughly 390,000 cubic yards of soil, ballast and track materials during construction of approximately 35–36 miles of track and six stations. "We did estimate ... 390,000 cubic yards of materials were going to be excavated," Stiller said. He reported the construction program ultimately achieved about 93% actual reuse, keeping roughly 360,000 cubic yards out of landfills.
Stiller credited early planning, integration of reuse into design, contractor incentives, rigorous material tracking (material shipping records and a program-wide master spreadsheet) and MassDEP Southeast Region concurrence for the outcome. He also noted geotechnical constraints and contaminant concentrations (notably arsenic and PAHs) shaped reuse decisions and placement: "Geotechnical properties were also critical ... just as important to consider." The project used DEP concurrence and a special project designation permit to support the reuse strategy.
The presentation included examples of reuse: on-corridor placement where arsenic concentrations were consistent with historic railroad bed values, reuse of granite as artificial reefs, and local wetlands and resiliency benefits from design choices. Stiller said approximately 25,000 cubic yards still went off-site, mostly PCB-contaminated soils required by EPA to be disposed rather than reused.
MassDEP staff and presenters said the program's key lessons were planning, sequencing of transfers, contractor collaboration, staging and geotechnical sorting of material types. The MBTA project's reuse experience was offered in the COM 25 discussion as an example of how large, coordinated projects can achieve high reuse rates when regulatory and design teams coordinate early.
The department did not describe any financial payments made by MassDEP for reuse; it emphasized permitting, technical coordination and contract structure as enabling factors.
