Humboldt Bay Power Plant Decommissioning

Challenge
TRC was tasked with preparing the Humboldt Bay Power Plant (HBPP) site, a 60-year old electric power plant located in a residential neighborhood, for new power generation. Work included removing a 2.7 million gallon fuel oil storage tank, cleaning, demolition and abatement of structures and removal of underground utilities within the footprint of planned new power generation facilities. TRC also had to remove an underwater 4,200 foot fuel oil pipeline, with no information indicating its precise location or condition.

Solution
TRC was the prime contractor and provided project and construction management, health, safety and environmental services, as well as permitting. We utilized a comprehensive local hiring program and a community friendly diversity supplier participation program. TRC supported HBPP personnel with Nuclear Regulatory Commission (NRC) audits, Storm Water  Pollution Prevention Plans implementation and permitting support. Extricating the fuel oil pipeline from the bay required a multi-disciplinary team of engineers and deep-water divers, experienced in managing complex underwater infrastructure. Seizing advantage of the influence of the tides, the dive team demarcated the severance lines of the pipeline and drilled access points to introduce high density expandable foam into the pipe. The foam assured that residual product would be contained during pipe cutting and removal, as well as enhancing buoyancy, aiding in lifting and extraction. Extracted piping was placed on specially designed cribbage and barged to shore, where it was cleaned, inspected and prepared for shipment as recovered metals for salvage value.

Results

• Relevant ancillary structures and infrastructure were decommissioned and dismantled to support the construction of future generation. This project was performed with zero recordable safety incidents, zero “close call” incidents and no adverse environmental issues.
• The effectiveness of the processes employed for extracting 4,200 linear feet of fuel oil pipeline from Humboldt Bay as well as remediating and decommissioning of the 2.7 million gallon fuel oil storage tank is demonstrated through environmental sampling and analysis which documented no environmental compliance issues.
• Approximately 95% of the materials decommissioned in the performance of this scope of work were reclaimed and recycled, including 920 tons of masonry, 200 tons of asphalt and 12 tons of metals.

Project Location: Humboldt Bay Power Plant, Eureka, CA

Completion Date: 2010