Historical Impacts
PG&E’s environmental remediation program addresses contamination resulting from the historical operations of Pacific Gas and Electric Company and its predecessor companies dating as far back as the mid- to late-1800s. Our overarching goal is to clean up historical impacts by using leading-edge technical approaches and best practices for engaging local stakeholders and suppliers.
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(Skip to main navigation)Our Approach
PG&E remains committed to safely incorporating sustainable remediation practices and technologies into site cleanups. Since 2010, we have partnered with the California Department of Toxic Substances Control (DTSC) to implement our sustainable remediation approaches.
Involving the community early is a vital component of our remediation efforts. Locally, we communicate with city leaders, local businesses, community groups, and residents to promote awareness, solicit feedback and identify core issues of interest in our remediation projects. We partner on initiatives to address these issues, including hiring local unemployed residents, developing property disposition strategies that align with remediation efforts and sourcing local goods and services.
In addition, PG&E continues to deliver economic, social and environmental benefits through its environmental remediation work. Our work includes soil and groundwater cleanups, and field testing cutting-edge cleanup technologies to lower greenhouse gas emissions and minimize community impacts. In 2019, these activities contributed $5.5 million to the local economies near our project sites.
2019 Milestones
Natural Gas Compressor Stations
PG&E’s natural gas system includes eight compressor stations that receive and move natural gas throughout our service area. During the 1950s and 1960s, long before recognition of the environmental standards to which we adhere today, Pacific Gas and Electric Company used hexavalent chromium to prevent rust in cooling towers at the Topock and Hinkley compressor stations—a common industry practice at the time. These operations resulted in groundwater contamination, and PG&E continues to work diligently under the oversight of state and federal agencies and in coordination with local Native American tribal governments to address these legacy impacts.
At the Topock Compressor Station, we completed the design and permitting process and are constructing the long term groundwater remedy. The DTSC and the U.S. Department of the Interior approved the remedy design in April 2018 and DTSC also certified the Subsequent Environmental Impact Report. Construction of the first phase of remedy facilities started in October 2018 and will continue for approximately two years.
We also conducted soil investigation work in and around the compressor station property after years of planning and review with regulators and tribes. The data collected were used to develop a risk assessment that will help determine soil cleanup work that might be needed in the future. PG&E continues to work with agencies and stakeholders as the risk assessment is approved and an Engineering Evaluation/Cost Assessment (EE/CA) is developed for the U.S. Department of Interior. An approved EE/CA will allow expedited remediation of contaminated soil.
While the long-term groundwater remedy is being finalized, we continued operations of interim groundwater measures, which operate around the clock to help ensure that the Colorado River is protected from impacts. Built in 2005, the system has successfully controlled groundwater contamination, treating almost 960 million gallons of groundwater and removing more than 7,850 pounds of chromium.
PG&E also remains committed to protecting public health and safety while remediating the environment and responding to community concerns at the Hinkley Compressor Station. Through 2019, we estimate that at least two-thirds of the chromium present in the groundwater has been removed.
We also continue to work with community stakeholders to improve our local presence in the Hinkley community and support community investment priorities focusing on youth, health and wellness, education and workforce development.
Manufactured Gas Plant Sites
We continue to make progress as we voluntarily address over 40 Manufactured Gas Plant (MGP) sites previously owned or operated by Pacific Gas and Electric Company or its predecessor companies. MGPs were located throughout PG&E’s service area and across the country and used coal and oil to produce gas for lighting, heating and cooking in the mid- to late-1800s and early 1900s, until natural gas arrived in the 1930s.
In 2019, cleanup was completed at the offshore portion of the former Potrero Power Plant and MGP site in San Francisco, and we are working on documenting our cleanup activities and developing any necessary site maintenance plans.
Highlights include:
- Prepared properties for future uses. Cleanup work at the Potrero site in 2019 focused on the offshore sediments area. This work, combined with earlier work along the waterfront, will position the Potrero Power Plant site and Pier 70 properties for productive reuse.
- Hired local workers as part of the Topock, Hinkley and Potrero projects. PG&E has adopted a local-hiring strategy that has benefitted unemployed and homeless residents, often leading to future full-time jobs.
Measuring Progress
Sustainable Remediation
In 2019, we reduced cumulative greenhouse gas emissions by 485 metric tons and liquid wastes by 6.4 million gallons. We achieved these results by incorporating sustainable practices on our remediation sites:
- Using heavy construction and remediation equipment meeting Tier 3 and Tier 4 federal emission standards, reflecting the cleanest standards in the industry;
- Using alternative fuels and renewable sources of energy for equipment and vehicles; and
- Maximizing recycling, on-site reuse of materials and reductions in liquid and soil wastes generated during remediation.
We also aim to source our equipment and vendors from the local community. In 2019, we added about $5.5 million to the local economies near our project sites.
At our Marina project in San Francisco, we continued to use the e240 Electric Mini Excavator, the first in the world to match the performance metrics of a diesel-powered unit with a lithium-ion battery. The advantages of using this innovative equipment include using clean energy, less noise and fewer emissions.