Former Vallejo manufactured gas plant

Project Overview: PG&E is beginning the remediation (clean up) of a former manufactured gas plant (MGP) that operated near Curtola Parkway and Sonoma Boulevard. This work will address the contamination of soil and groundwater from historic gas making activities and will be conducted with the approval and oversight of the California Department of Toxic Substances Control (DTSC) and the City of Vallejo. This green approach will protect long-term public health and the environment while minimizing impacts to the local community and supporting future site redevelopment.


Former Vallejo manufactured gas plant in the 1920s


To minimize community impact and allow for greater flexibility for construction teams, the site has been divided into two areas, the 26-acre main site located to the south of Curtola Parkway and two privately owned properties located to the north of Curtola Parkway. The work will be conducted in two phases with work on the smaller privately owned parcel beginning in July 2021 and ending in December 2021. Work at the main 26-acre site will begin in the summer of 2021 and last approximately three years.


Work on both sites includes a combination of excavation and off-site disposal of shallow soil that was impacted by historic gas-making activities and adding a cement mixture to solidify impacts to deeper soil in place. Excavated areas will be backfilled with clean, imported fill and work areas will be restored.



Public Safety and Outreach: Safety is of utmost importance to PG&E. Work is conducted in accordance with a DTSC-approved health and safety plan that includes proven best practices for air and vibration monitoring, dust management and truck traffic control, as well as safety measures to reduce the risks of COVID-19. PG&E will continue to keep the community informed about the project through fact sheets, work notices and other outreach, as appropriate.

Site History: The former MGP operated from the late 1800s to 1930 and provided a constant source of energy for the Vallejo community’s lighting, heating and cooking needs prior to the arrival of natural gas. Some byproducts of the gas making process were left buried on-site as the plant was dismantled – a common practice before environmental regulations – and PG&E is cleaning up the property in accordance with today’s standards.


Site overview about gas making operations