Chris Schneidmiller
WC Monitor
8/7/2015
The contractor building the Waste Treatment and Immobilization Plant (WTP) at the Hanford Site in Washington state has prepared a comprehensive but not complete analysis of possible hazards to one of the plant’s facilities, the Department of Energy’s Office of Enterprise Assessments said in a review made public on Tuesday.
The DOE report focuses on Bechtel National’s December 2014 hazards analysis covering the ammonia reagent system (AMR) and carbon dioxide gas system (CDG) at the low-activity waste (LAW) facility, one of four key components of the still-under-construction WTP. The plant ultimately is intended to process millions of gallons of radioactive and chemical waste now stored at Hanford. The LAW facility, which is more than 70% complete, will process liquid low-activity waste into glass form for disposal.
The DOE branch said its report is part of continuing oversight to ensure nuclear safety is incorporated into the design of the WTP. It highlighted the AMR and CDG due to the “potentially high consequences from accidents involving those systems.”
“The Bechtel National, Inc. hazards analysis team used a thorough hazard identification process to identify the hazards requiring analysis. Overall, the hazards analysis team analyzed event types appropriate to the systems and developed a comprehensive set of events,” according to the DOE report. “This hazards analysis report focuses on completing unmitigated event analyses and, for the most part, includes conservative estimates of the material at risk and unmitigated consequences. The identified candidate controls, along with the specified safety functions and attributes, provide a mostly complete set to support control selection.”
DOE, though, also cited a number of areas in need of improvement. Specifically, the “hazards analysis report does not adequately describe the relationship between the candidate design basis accidents and the underlying bounded hazard events for these systems,” the report says. Auditors also “identified some weakness in the areas of hazard identification, hazards analysis, and candidate hazard control documentation.”
While Bechtel appeared to have comprehensively identified possible dangerous substances and energy sources at the facility, DOE found that a “number of events associated with AMR failures could result in unanalyzed hazards with significant consequences” for segments of the WTP through releases of gases and what the department called unmitigated system effects.
Bechtel’s hazards analysis encompassed 77 potential events at AMR and 78 at CDG, including fires, explosions, dangers originating outside the facilities, and natural events, many of which could lead to a “boiling liquid expanding vapor explosion” (BLEVE) If not controlled. DOE, though, identified wildland fires as one area needing greater attention, and said more detail was needed in some analyses of the sequence of events leading to a release of ammonia or carbon gas.
The department emphasized in the report that it prefers facilities to incorporate measures to prevent a hazardous event over those to lessen the impact of such an event. But Bechtel has appeared to lean on mitigative controls for hazards at the AMR, DOE said, and there were “missing, inappropriate, or misclassified candidate hazard controls” for certain events, which could lead the company to employ “an inadequate set” of hazard countermeasures.
The DOE report offers eight recommendations to Bechtel, which the department cautioned “are not intended to be prescriptive or mandatory.” Suggestions included listing wildfires among the potential hazards considered for the AMR system and updating event descriptions in design basis accidents – those events the facility must be built to withstand – “to ensure the sequence of events is sufficiently described to support identification of the causes and potential controls of the event.”
Bechtel spokeswoman Suzanne Heaston said the company received the DOE report this week. “We recently completed a two-month effort working closely with the DOE Office of River Protection to revise our internal processes and procedures aimed at improving the consistency and completeness of our hazards analyses,” she said in an email statement to Weapons Complex Monitor. “Our initial review of the report indicates that the single finding and eight suggestions for improvement are consistent with opportunities for improvement previously identified by DOE-ORP and BNI that led to the recent process changes. We will be working with DOE to formulate any follow-up actions.”
East Tennessee Technology Park Emergency Plan Needs Update, DOE Says
The Office of Enterprise Assessments this week released a separate evaluation of management planning for hazardous materials releases, natural disasters, or other emergencies at the East Tennessee Technology Park, the site of former DOE uranium enrichment operations now undergoing environmental rehabilitation, decontamination, facility decommissioning, and legacy waste management while being reindustrialized for private use.
“Overall, the technical planning basis for ETTP, which forms the foundation of the emergency management program, is sound. Onsite protective actions and offsite protective action recommendations are adequate to protect the health and safety of the onsite and offsite populations,” the report found. “Emergency plan implementing procedures provide necessary details for effectively executing the response to an Operational Emergency.”
However, DOE also cited three key areas “of emergency management weakness” by site contract operator URS-CH2M Oak Ridge (UCOR) and the DOE Oak Ridge Office of Environmental Management (OREM).
UCOR has not updated the plan since assuming management of the facility in August 2011, though a revised document is expected by the end of September. In the interim, the existing plan does not accurately represent the status of some facilities and fails to include “severe event considerations,” among other issues, DOE said.
The report also notes that emergency drills have not been expanded to encompass additional crisis situations, hazards, and facilities. With UCOR not rotating “the basis for the annual site exercise between all of the facilities with emergency planning assessments … emergency response organization personnel do not practice responding to emergencies at all facilities that could have hazardous material releases with significant consequences.”
Finally, it is not always clear in UCOR or DOE assessments that staffers at ETTP are sufficiently carrying out actions mandated during UCOR updates to its emergency planning at the site, the report says. In some cases, measures intended to address problems cited in those assessments either failed to do so or would not ensure the problems did not occur again.
UCOR spokeswoman Anne Smith said by email Thursday that the contractor has “taken aggressive steps to review and strengthen its emergency response procedures, bringing our response capability to the highest standards required by our company and DOE. Many of the steps addressed issues identified in the latest DOE Emergency Management Evaluation report.”
The company this year updated the emergency plan covering all of ETTP to “reflect the current reconfiguration of the site, which includes the reindustrialization efforts,” she stated. “That emergency plan was approved by DOE in June.” UCOR and OREM that month also conducted a large emergency drill at the site, and facility-specific exercises are ongoing, Smith added.
