Field work is expected to begin at the former manufactured gas plant in Colusa next week.
The California Department of Toxic Substances Control (DTSC) has been overseeing a clean-up of PG&E’s former manufactured gas plant, located at 105 Second Street in Colusa, for several years.
The property was once a manufactured gas plant from about 1886 to 1940, according to a release issued by DTSC, with the gas used for the lighting, heating and cooking needs of the Colusa community until PG&E built natural gas transmission lines.
PG&E has since retained the land for a substation and work yard, and has made the voluntary effort to remediate soils at former manufactured gas plants including the location on Second Street. Soil on part of the Colusa property was removed in 2013 during the first phase of remediation but the utility has more plans in the works for the site as they move into phase two.
“PG&E plans to replace electrical equipment on the western side of the substation which provides the opportunity to cleanup soil contaminated with polycyclic aromatic hydrocarbons (PAHs), total petroleum hydrocarbons (TPH), arsenic and lead from past MGP operations,” said Kerry Rasmussen, public participation specialist for DTSC.
PG&E will de-energize and remove electrical equipment from the site before excavating approximately 1,870 cubic yards – roughly 140 truckloads – of soil to ten feet below the ground surface from the southeast side of the site, according to the release. The soil will be transported to a licensed disposal facility and backfill excavations with clean fill will be added before the area is graded to prepare for the replacement of electrical work.
Project documents, including the Health and Safety Plan, can be viewed online at https://tinyurl.com/x4e728td.
Work is scheduled to begin Aug. 3 and will last approximately three month, according to the release.
Work will be conducted within the hours of 7 a.m. and 7 p.m. Monday through Friday. If weekend work is required, the hours will be limited to 8 a.m. to 7 p.m. in accordance with City permits.
According to the release, the work will cause some noise and vibrations in the area but all work will be performed in accordance with a site-specific Health and Safety plan that includes a dust and odor control plan, a noise control plan and a traffic control plan.
“In order to allow for work activities to occur safely, the alleyway south of the substation and a section of First Street between Main Street and the alleyway will be closed to vehicle and pedestrian traffic,” it was stated in the release. “If needed, the southbound lane of First Street may also be closed from the alleyway to Market Street. The sidewalk and parking lane on the south side of Main Street between First and Second Streets will also be closed. Detour signs will be posted.”
During the height of cleanup – from August to October – an estimated eight to 20 roundtrip truck trips may occur daily to remove soil and bring fill material to the substation and flaggers may be on-site to safely manage truck, car and pedestrian traffic.
“Trucks would follow a City-approved truck route traveling south on First Street, turning right onto Market Street and then either turning left onto 10th Street/Hwy 20 or turning right onto
Second Street, right onto Main Street and right onto Hwy 45,” according to the release.
To reduce the risks for COVID-19, state and local measures will be followed while the project is conducted, such as physical distancing, personal protective equipment including face coverings, and sanitary hand washing stations.
For more information, contact Project Manager Karri Peters at 916-255-3614 or email Karri.Peters@dtsc.ca.gov.