Kenneth Fletcher
WC Monitor
3/13/2015
The Defense Nuclear Facilities Safety Board is calling on improvements for controlling safety risks at Hanford after completing a review of decommissioning safety systems at the site’s Plutonium Finishing Plant, according to a letter sent to the Department of Energy late last week. An attached DNFSB staff report highlighted numerous potential safety issues at the PFP project. “Collectively, these issues illustrate a need to improve [the Department of Energy’s] processes for evaluating, controlling, and accepting the safety risks inherent in hazardous cleanup activities at Hanford. While decommissioning activities at PFP are approaching completion, DOE is confronting other hazardous cleanup missions at Hanford,” states a March 6 letter from acting DNFSB Chair Jessie Roberson to acting Assistant Secretary of Energy for Environmental Management Mark Whitney.
The PFP produced plutonium metal during the Cold War and was shut down in 1996. Hanford cleanup contractor CH2M HILL Plateau Remediation Co. aims to completely demolish the facility to “slab on grade” by the September 2016 date in the Tri-Party agreement between DOE, the state of Washington, and the Environmental Protection Agency. CHPRC is currently undertaking corrective actions after a DOE Inspector General report found issues with CHPRC’s ability to plan, manage and execute work at PFP, which have contributed to significant delays and cost increases at the project.
The recent DNFSB review looked at various safety aspects of the project, including safety system classifications and ventilation system and exhaust fan reliability. “The specific examples cited in this report highlight decisions by the PFP contractor, CH2M HILL Plateau Remediation Company (CHPRC), and the Department of Energy’s Richland Operations Office (DOE-RL) that led to inadequate controls for high risk scenarios, unfiltered release pathways from the facility, and safety systems that may not perform their safety functions due to improper control of their support systems,” the DNFSB report states. “Additionally, the review team identified the potential for bypass leakage around the safety-significant high-efficiency particulate air (HEPA) filters during certain accident scenarios.” CHPRC and DOE Richland did not respond to request for comment by press time this week.
DNFSB Considered ‘System Back Out Plan’
For example, DNFSB staff looked at CHPRC’s “system back out plan,” which identifies actions for securing and downgrading safety systems over the life of the project as work is completed and hazards are reduced. “The review team observed that the back out plan does not yet contain step-out criteria for major safety systems,” the report states. “A conclusion regarding their adequacy can therefore not be reached at this time. CHPRC personnel will develop the step-out criteria in a future revision of the DSA.”
Ventilation System a Concern
The DNFSB also looked at the ventilation system, which is crucial to risk reduction in the case of an accident, noting that in 2011 one of the exhaust fans “failed catastrophically.” The report notes: “In response, CHPRC personnel undertook an extensive campaign to refurbish fan components and improve fan reliability.” It adds: “The review team concluded that CHPRC and DOE-RL personnel have made significant improvements to limit the risk of a future failure such as replacing aging fan components and enhancing predictive and preventive maintenance activities. However, in evaluating the back out plan and the ventilation system, the review team identified a number of safety issues concerning CHPRC’s and DOE-RL’s evaluation and acceptance of risk on the project.”
