GEI Consultants provided integrated assessment, environmental, and geotechnical services for One First Street, a dramatic redevelopment of nearly an entire city block in East Cambridge.
The property, which was most recently owned and operated by the Necco Candy Company, is being redeveloped into nearly 200 residential condominium units with additional commercial and retail units at street level. Distinctive residential buildings have been carved out of this historic city block and surround a magnificent private courtyard. There is underground parking under almost the entire 72,000-square-foot property. Phase I of the project was completed in 2006, and Phase II will be completed in 2007, both on schedule.
The transformation of this property included the demolition of several buildings, the gut-rehabilitation of others, and the construction of two completely new structures and underground parking. The original structures retained were built between 1866 and 1929 and represent several styles of American Industrial Architecture. Saving these historic structures was important to the Cambridge Historical Commission and to the redevelopment concept. As part of the redevelopment, GEI designed new foundations, monitored construction of the new building foundations and underground utilities, and managed the off-site disposal of excavated materials, including contaminated soil. GEI also performed vibration and settlement monitoring at surrounding properties and performed odor and air monitoring for hydrogen sulfide during excavation of peaty material.
Challenges included integrating the historic buildings with the new construction, repairing timber piles that supported the historic structures, removing an underground storage tank, performing construction dewatering discharge in accordance with a Remediation General Permit (RGP), and removing nearly 20,000 cubic yards of oil, lead, and polyaromatic hydrocarbon contaminated soil. Coordinating the disposal of uncontaminated peat that had a high salt content (associated with ancient tidal marshes) proved to be an interesting twist to the more standard soil management. All this work was performed as a Release Abatement Measure (RAM) under the Massachusetts Contingency Plan (MCP), and the site is scheduled to achieve regulatory closure in 2007.