Landfill Solar

Borrego Solar Systems, Inc. Chelmsford Landfill Solar PV Facility

gzadan — Mon, 06 Dec 2021 14:29:05 +0000

Borrego Solar Systems, Inc. Chelmsford Landfill Solar PV Facility gzadan Mon, 12/06/2021 - 09:29

Borrego Solar Systems, Inc. is a solar development company that specializes in ground-mount solar farm and energy storage projects. The Chelmsford project consisted of the development of a solar farm over an existing landfill for the town of Chelmsford’s “Community Shared Solar Project�� making solar energy available to residents unable to construct solar panels on their own property. GZA was contracted to provide geotechnical foundation recommendations for the battery storage and equipment pads, as well as landfill capping recommendations.

Challenge

The proposed equipment and battery storage pad was located adjacent to the landfill cap in an area supposedly outside the landfill area. After the contractor excavated for shallow pad foundations, landfill waste was observed below portions of the proposed pad area. Geotechnical borings then performed at the location of the pad indicated that landfill material extended up to 17 feet below ground surface. Landfill waste would not properly support the pad structures. The loads from the equipment and energy storage modules on the pads required an intermediate/deep foundation system be designed to transfer loads to competent soil below the waste. GZA selected helical pile foundations to support the loads. Once the helical piles were installed, the structural zone directly below the pads needed to be properly sealed and capped over the landfill waste.

Solution

GZA designed a helical pile foundation system to support the equipment and battery storage pads, working closely with the structural engineer. Geotechnical analyses, including the evaluation of pile group effects, were performed by GZA. The pile installation, performed by Conte, was observed by GZA to confirm and document that the installation procedure was in conformance with the contractor’s submittal previously reviewed and approved by GZA. GZA evaluated several capping alternatives and provided landfill capping design and construction sequencing for once the piles were installed.

Benefit

GZA provided services to help our client quickly change from a shallow foundation to a helical pile foundation to support the pad area.

Provided geotechnical design recommendations for equipment pad support on shallow foundations
Excavation during construction identified landfill waste outside the assumed landfill area
Landfill waste would not provide suitable bearing conditions for the equipment pad, requiring GZA design helical piles to carry loads below the waste
Designed new capping to seal the waste below the pile penetrations of the existing landfill cap
Observed and documented pile installation

Energy

Geotechnical Engineering Services

Kearsarge Energy 3.6 MW Solar Energy Project

gzadan — Fri, 05 Nov 2021 19:31:44 +0000

Kearsarge Energy 3.6 MW Solar Energy Project gzadan Fri, 11/05/2021 - 15:31

Challenge

Kearsarge Energy wished to develop a solar array on a portion of the long-vacant, 55-acre landfill on Old Groveland Road. The project included construction of a new access road with a turnaround area at the end and a stone-lined stormwater channel running along the road. A third-party, independent Massachusetts-registered professional engineer knowledgeable in landfill design and construction was needed to supervise the overall construction of the photovoltaic system.

Solution

GZA served as the client’s third-party Construction Manager for services in accordance with the Post-Closure Use Permit’s (PCUP) conditions issued by the Massachusetts Department of Environmental Protection (MADEP) for the site. GZA prepared and submitted a Notice of Construction (NOC) to MADEP including a schedule for completion with major construction milestones of the PV facility notated. The overall construction of the photovoltaic system was performed under the direct supervision of a MA professional engineer as required. After each visit, GZA produced a written field summary documenting the number of on-site personnel present, work performed during the visit, general site housekeeping, conformance to best practices, adherence to construction documents and permit conditions, construction means and methods, and equipment installed. GZA performed a detailed slope stability analysis that demonstrated the ballasted racking system with some ground improvement was stable on slopes up to 30%. At the completion of the solar array installation, GZA performed inspections of both the solar array and landfill cap on a quarterly basis for one year and submitted a report to MADEP summarizing the inspection.

Benefit

GZA fulfilled the MADEP’s requirement for an independent third-party construction manager, which allowed the client to complete its development and installation of a 3.0 MG solar array system on a closed landfill. The City of Haverhill stands to net approximately $3 million in revenue over the next 20 years. The slope stability evaluation was accepted by state regulators and allowed our client to maximize the power output of the system.

Third-party construction management and inspection services
Slope Stability Analysis
8.25-acre/ 3.6 MW (DC) solar array
Post Closure Use Permit Modification
Required construction of new access road with stormwater channel

Energy

Construction Management

Solar Development at Rose Hill, ��Ϸ��st Kingstown, and University of Rhode Island (URI) Superfund Landfills

Anonymous — Thu, 26 Sep 2019 13:51:15 +0000

Solar Development at Rose Hill, ��Ϸ��st Kingstown, and University of Rhode Island (URI) Superfund Landfills Anonymous Thu, 09/26/2019 - 09:51

Challenge

From permitting to construction completion, this solar development program in partnership with Kearsarge Energy �� design and construction of a solar field atop three previously capped landfills �� presented challenges: as the first project of its type in the state, the permitting process was without precedent; protection of the landfill caps was paramount; and as-built vs. design discrepancies were encountered during construction at one site.

Solution

Drawing upon a successful permitting track record in neighboring states, GZA developed and presented a permitting process to the owners, EPA, and RIDEM, who readily adopted the process for this project. GZA’s geotechnical study for Kearsarge and other stakeholders included a bear capacity analysis and design of the ballast block foundations to maximize the number of solar arrays installed at each landfill while maintaining minimal ground pressure, to protect the landfill cap; this resulted in different-sized ballast blocks specialized for each location. To further protect the cap, GZA used low ground pressure equipment to manage construction activities, advised the contractor on weather/ground condition-related scheduling, and provided input on the design of all the wiring and supporting trays for the above-ground installation. During construction, GZA conducted a crane feasibility analysis for the installation of the transformer, and, when design issues at one site resulted from inaccuracies in the as-built drawings provided, GZA completed necessary stormwater analysis and restoration design to address unexpected erosion after the solar array installation.

Benefit

This project tapped a broad range of GZA’s technical capabilities and benefited from GZA’s stellar reputation with federal, state, and local regulatory agencies, helping move this first-of-its-kind Rhode Island project through the regulatory and construction process on time and under budget, while protecting the integrity of the landfill caps at all times.

Insights

Unprecedented permitting process within Rhode Island
Bearing capacity analysis and ballast foundation design
Protection of Superfund landfill cap was paramount during design and construction
Construction oversight

Rhode Island

Energy

Land Use and Environmental Planning

Geotechnical Engineering Services

EHS Regulatory Compliance

Construction Management

Energy and Sustainability Services