Taking Responsibility for Our Historic Impacts
Joined at a grand opening by local officials, community residents and
a dedicated local developer, PG&E celebrated turning a brownfield into a
green building, Villa del Sol.
At PG&E, we continue to take responsibility for cleaning up historic or "legacy" contamination from operations during past eras, in some cases 100 years ago or more. Typically, contamination stems from a substance that was acceptable and widely used in the past but that is now considered hazardous.
For example, from the late 1800s until the early 1900s, utility companies nationwide operated manufactured gas plants that converted coal and oil into gas for lighting, heating and cooking. The gas-making process produced residues, such as tar and other petroleum-related compounds similar to those found in gasoline or diesel fuel. While the plants were operating, some of the residual by-products were used and sold as products, such as briquettes and coal tar. When the plants were shut down, however, consistent with standard practices of the time, many of the by-products were buried onsite. Modern science has since identified some of these by-products as hazardous, and utilities, including PG&E, are working to clean up these sites.
In 2007, our Environmental Remediation group worked on 80 projects, involving the community and neighbors in the process.
For example, in Napa Valley, we worked with the city of St. Helena to develop a plan for converting a cleanup site into a much-needed public parking lot. Historic use of the one-acre parcel as a manufactured gas plant and electrical substation had contaminated the soil. The St. Helena Gas Company built the plant in 1886 and operated it for many years. By 1930, PG&E acquired the site and built a substation which operated until 1989. The site has been vacant since. In partnership with regulators, PG&E removed 9,750 tons of contaminated soil from the property, replacing it with clean fill. We hope to receive regulatory approval shortly to lease the parcel to St. Helena so that the city can begin construction in summer of 2008. The much-anticipated parking lot will help reduce the ongoing problem of congestion in downtown St. Helena and support the local business community.
PG&E's Topock Compressor Station
PG&E’s Topock Compressor Station is located in San Bernardino County, about a half mile from the Colorado River. Consistent with industry practice at the time, hexavalent chromium was used at Topock in the cooling towers in the 1950s and 1960s to prevent corrosion. Beginning in 1951 until 1964, untreated wastewater from the cooling towers was discharged into a nearby dry wash. Over time, the discharged hexavalent chromium reached and contaminated the groundwater aquifer. PG&E is characterizing the magnitude and extent of contamination through an extensive groundwater monitoring network. Additionally, PG&E’s monitoring program continues to show no presence of hexavalent chromium in the Colorado River.
PG&E has been monitoring the groundwater plume for several years and has been working cooperatively with state and federal regulators and other interested parties to evaluate and remedy this groundwater contamination. In early March 2004, state regulators required PG&E to begin operating a groundwater extraction system as an interim protective measure to ensure that the chromium plume is hydraulically controlled so it does not reach the Colorado River. In July 2004, PG&E initiated treatment of the hazardous groundwater prior to offsite disposal and, subsequently, expanded the groundwater extraction and treatment system. That expansion was completed in July 2005 and includes a treatment plant, which cleans the extracted groundwater so it can be reinjected into the groundwater aquifer.
PG&E also continues to work with state and federal regulators to complete the characterization of groundwater and soils at the site.
There are several potential options for a long-term remedy, including expanding the groundwater extraction system and using in-situ treatment to remove hexavalent chromium from groundwater in place. PG&E is working with state and federal regulators and key stakeholders, including Native American tribes, to complete the evaluation of contamination at Topock and develop alternatives for the final remedy in an expedited manner.
We continue with efforts to complete several actions required under the settlement agreement with the Ft. Mojave Tribe, most notably finalizing the language of the sitewide easement and thereafter transferring title to the IM-3 site property to the Tribe. We have also finalized a memorandum of understanding with the Colorado River Indian Tribe and are close to finalizing one with the Hualapai Tribe. These agreements will help ensure that these tribes have the ability to meaningfully participate in the remedy development process.
In another example of working closely with a community, we helped transform a former electrical substation site into a location for new state-of-the-art green housing. Located in Martinez, one of California's first towns, the site originally housed a substation built in the early 1900s. To prepare the site for new development, PG&E removed 1,378 tons of existing soil and replaced it with clean fill. We worked closely with local developers throughout the process to meet stringent city and county requirements for remediating the land to residential-use standards. The site now features Villa del Sol, a complex of eight new LEED™-certified affordable luxury homes. Designed by a local architect, the homes incorporate a variety of sustainable design and construction practices, including ENERGY STAR® appliances, windows and central air and heating.
This project is an example of PG&E's broader support for brownfield development, sustainable communities and policies and initiatives that advance urban infill as a key component of smart growth. In 2007, this support also included hosting a California Center for Land Recycling workshop for agencies, developers and consultants. In the workshop, U.S. EPA, Cal/EPA and private financial firms educated attendees on public and private funding sources available for brownfield redevelopment.