Manufactured Gas Plants
Former St. Helena Manufactured Gas Plant
PG&E is working to address environmental impacts at the site of a former manufactured gas plant (MGP) located at 1301 Mitchell Drive in St. Helena, California that operated from 1883 to 1930. PG&E acquired the property in 1930 and used it as an electrical substation until 1989. All work is being conducted voluntarily by PG&E and is being overseen by the California Department of Toxic Substances Control (DTSC).
PG&E completed investigation work at the site and continues to cleanup soil and groundwater. In 2007, PG&E completed Phase One of a large-scale soil excavation and installed a treatment system to remove MGP residues from soil and groundwater at the site. PG&E expanded the system in January 2011 to remediate another portion of the site. PG&E will begin Phase Two of the cleanup in spring 2014 and expects to complete site remediation by fall 2014.
Under an agreement with PG&E, the City of St. Helena is using a portion of the remediated property as a parking lot through April 2014, when PG&E will need the parking area for Phase Two of the cleanup. This interim parking lot provides the City with free all-day parking for about 40 cars. PG&E and the City of St. Helena will discuss post-remediation site uses.
PG&E will continue to keep the community informed about this project through fact sheets, work notices and other outreach, as appropriate.
- City of St. Helena E-newsletter Article – Public Works Featured Project: PG&E Parking Lot - July 2013
- St. Helena: PG&E Shares Parking Lot During Busy Tourist Season – June 2013
- City of St. Helena E-newsletter Article – Downtown Parking Comes to PG&E Lot on Mitchell Drive - June 2013
- City of St. Helena E-newsletter Article – Downtown Parking Ribbon Cutting Event - June 2013
- Soil Sampling Work Notice - April 2013 (PDF, 196 KB)
- Work Notice – December 2010 (PDF, 100 KB)
- DTSC Resources & Contact Information
Site-related documents can also be found at:
St. Helena Public Library – Reference Desk, 1492 Library Lane, St. Helena (707-963-5244)