Potrero Power Plant
Frequently Asked Questions
Where is the Former Potrero MGP Remediation Site?
The Site is located in San Francisco's Central Waterfront area at 1201 Illinois Street. It is approximately 34 acres in size and is bordered by 23rd Street to the south, Illinois Street to the west, the Pier 70 site to the north, and San Francisco Bay to the east.
What is the site's history?
The site and adjacent area have been used for industrial activities since the mid-1800s. Some of the historic uses on and near the site included ship building and repair, foundries, sugar refining, and barrel making. PG&E and its predecessors operated a manufactured gas plant (MGP) in the northeastern portion of the site from the 1870s to the 1930s. A power plant, commonly referred to as the Potrero Power Plant, was built in the 1910s and upgraded and expanded in the 1960s, with the construction of Unit 3. PG&E sold the power plant property to Southern Company (subsequently, Mirant Corp., then GenOn and now NRG, Potrero LLC) in 1999, while retaining portions of the site for such uses as an electrical switchyard and storage. The plant was shut down in March 2011 following the completion of the Trans Bay Cable project, which allowed power generated in Pittsburg to be transferred across the Bay to San Francisco. While PG&E no longer owns the Potrero Power Plant, we are taking responsibility for the impact of our former operations.
What is a manufactured gas plant?
In the mid 1800s and early 1900s, before natural gas was available as an energy source, more than 1,500 manufactured gas plants (MGPs) were located in cities and towns across the country. These plants used coal and oil to produce gas for lighting, heating and cooking. With the arrival of natural gas in the 1930s, most of the manufactured gas plant sites in California were no longer needed and were closed.
What are the environmental impacts at the site?
The site has a long history of industrial use and has environmental impacts associated with this industrial past. The primary impacts at the site are associated with leftover MGP residues. MGPs produced a variety of byproducts, some of which were useful and marketable, such as coal tar and lampblack. The byproducts that could not be sold were removed for disposal or remained at the MGP site. Residue found at some MGP sites is comprised of various chemicals, including polycyclic aromatic hydrocarbons (PAHs) and volatile organic compounds (VOCs).
Heavy metals have also been detected in site soil, along with naturally occurring asbestos, both of which can be associated with fill material or the serpentinite bedrock located beneath the site and surrounding area. Petroleum hydrocarbons have been identified in soil and groundwater.
What is the status of the remediation of the property?
PG&E has made significant progress on the environmental investigation and remediation of the Former Potrero Power Plant Site. The site has been divided into seven work areas to facilitate the remediation process. This allows us to investigate and remediate each area independently, and not delay work toward redevelopment in some areas, while conducting necessary work or studies in other areas. In 2012, we finished remediation work in two of the seven project areas: the Hoe Down Yard and the Switchyard and General Construction Yard Area. PG&E, NRG and the Water Board are continuing efforts to finalize closure documents for the Station A Area, another large area of the site. This leaves work in four remaining areas: the Northeast Area, the Offshore Sediment Area, the Tank Farm, and the Power Generation Facility. Visit the Cleanup Areas and Recent Activities page for an area-by-area overview of recent activities across the site.
After the remediation and cleanup of the site is complete, what will the site be used for? How will future uses of the site be incorporated into the City’s plan to redevelop this area of San Francisco and the adjacent Pier 70 property?
The areas of the site owned by PG&E, such as the Switchyard and General Construction Yard will continue to operate as PG&E facilities. The Hoe Down Yard is also currently being used by PG&E; however, the property may be incorporated into the pending Pier 70 redevelopment plan in the future. PG&E and the Port of San Francisco are currently negotiating this potential. The former Power Plant area of the site is owned by NRG who will decide its final disposition.
Who owns the former Potrero Power Plant property?
PG&E sold the Potrero Power Plant property in April 1999 to Southern Company (subsequently, Mirant Corp., then GenOn and now NRG Potrero, LLC). Other areas near the power plant property, such as the Switchyard and General Construction Yard and Hoe Down Yard, are currently owned by PG&E.
Why is PG&E cleaning up the former Potrero Power Plant property?
While PG&E no longer owns the former Potrero Power Plant, we are taking responsibility for the impact of our operations. Investigations will be conducted subsequent to the former plant's demolition by NRG and a cleanup plan will be formulated based on site data and anticipated future use. It is PG&E’s responsibility to clean up the site so it can continue to be for industrial/commercial uses; any additional remediation required for a different use (such as a park) will be the responsibility of the land owner.
Who is overseeing the remediation?
PG&E is working under the oversight of the San Francisco Bay Regional Water Quality Control Board (Water Board), an organization within the California Environmental Protection Agency, which is the lead agency overseeing the environmental investigations and cleanup. In addition, PG&E is coordinating remediation efforts with the City and Port of San Francisco and several other local, state and federal agencies, including the California Department of Fish and Wildlife.
Are there health risks to the community as a result of impacts to the soil, groundwater, surface water and sediments?
No. All information that we have collected to date indicates that there is no health risk to the public from environmental impacts under current property use.
What is PG&E doing to protect air quality during the cleanup effort?
PG&E will take all necessary precautions to protect the community and site workers during the construction activities associated with cleanup activities. This will include a dust mitigation and air monitoring program that adheres to all federal, state and local guidelines.
What formal procedures has PG&E put in place in order to ensure community members have an opportunity to comment on the remediation and cleanup plans?
We have put together a comprehensive community outreach plan for this site. Our community outreach efforts include regular project newsletters, community planning meetings and stakeholder outreach. Newsletters with progress updates are periodically mailed to approximately 1,400 local residents and key stakeholders. In 2012 we held two community meetings to discuss PG&E's efforts at the site with the community and incorporate input into our cleanup plans for the Northeast Area and in 2013, one community meeting was held to discuss the results of the offshore sediment investigation and provide updates on other areas. Another community open house was recently held to discuss the Pilot Test in the Northeast Area. In addition, the Water Board has a public participation program for the site. This includes invitations to comment on various draft feasibility studies and cleanup plans. The Water Board also invites community members to participate in Public Meetings. For example, in 2012 the Water Board solicited feedback to inform the final cleanup approach for the Northeast Area. All members of the community are encouraged to contact the project team via the contact information listed on the right hand side of this page.