Design Review Finds Vulnerabilities At a Number of Facility Systems
Mike Nartker
WC Monitor
9/12/2014
In a significant step forward toward completing one of the main portions of the Hanford Waste Treatment Plant, Bechtel National has received approval to resume “full production engineering” at the vit plant’s High-Level Waste Facility. As a result, Bechtel National can now move forward with “all engineering work necessary to finalize the design” of the HLW Facility, as well as to proceed with “limited procurement and construction,” according to an Aug. 19 letter from the Department of Energy obtained by WC Monitor this week. Questions persist, however, as to when the facility will be completed, or when DOE will be able to determine the schedule for completion. The resumption of full production engineering “allows us to do the work to get to the resolution point. … It’s at that point we can begin to inform what the path forward is for HLW,” Bechtel National Project Director Peggy McCullough told WC Monitor late this week.
DOE moved to largely suspend work at the Hanford vit plant’s HLW Facility in the summer of 2012 because of the need to fully resolve long-standing technical concerns such as ensuring adequate waste mixing and preventing erosion and corrosion. In the interim, the only work performed at the facility has focused on civil construction activities, such as placement of concrete and structural steel, while Bechtel National has performed additional engineering studies to help address the remaining areas of technical concern. This spring, the Department gave Bechtel National approval to resume “limited production engineering” activities at the HLW Facility, which allowed the contractor to move forward with some design activities for facility systems, but not to proceed with related procurements or construction work.
Technical Issues ‘Substantially Resolved,’ DOE Says
Among the reasons for DOE allowing full production engineering to resume, according to the Aug. 19 letter, is Bechtel National having “substantially resolved” technical issues at the HLW facility. For example, to resolve concerns over waste mixing, Bechtel National completed an engineering study for the four HLW Facility vessels in question and determined they would be able to meet their mixing function, Bechtel National Technical Director and Design Authority Russell Daniel told WC Monitor late this week. To resolve erosion and corrosion concerns, Bechtel National completed risk assessment of all piping and vessels in black cells and identified less than a dozen that posed potential risks, Daniel said, adding that the contractor has identified design or operational changes to mitigate such risks.
Other factors in DOE’s decision to allow full production engineering to resume, according to the Aug. 19 letter, include Bechtel National having submitted corrective action plans to address nine technical- and quality-related Priority Level 1 findings. A new Safety Design Strategy for the HLW Facility has also been developed and approved, and Bechtel National has “revised its design and nuclear safety processes, aligned roles and responsibilities and developed plans and procedures to implement the HLW SDS,” the letter says.
Review Finds Issues That Could Impact Facility Operability, Functionality
DOE’s decision to allow full production engineering to resume was also based on the completion of a review by independent experts to examine design and operability issues at the HLW Facility, as well as Bechtel National’s subsequent efforts to develop responses to the review’s findings. The review examined 12 out of 24 facility systems and found “project issues that, unless resolved in a timely manner, may result in unacceptable risk to the over project mission,” according to a report of the review’s findings that DOE released late this week. “The review teams identified significant vulnerabilities that could limit HLW Facility functionality and operability. Concomitant fundamental weaknesses and breakdowns in design process implementation, which may be a root or contributory cause of many of the identified vulnerabilities, also were revealed,” the report says.
The design and operability review examined systems in four areas of the HLW Facility—canister systems, mechanical handling systems, process support systems and ventilation systems—and identified vulnerabilities as posing “high,” “medium” or “low” significance. For example, the review identified nine “high” significance vulnerabilities, 11 “medium” and one “low” in the HLW Facility’s Melter Offgas Treatment Process system and Process Vessel Vent system, which are intended to help protect human health and the environment by treating emissions from the facility’s melter before discharge. “The primary consequence of the vulnerabilities identified is anticipated failure of this system that will cause frequent and persistent outages resulting in significant facility production impacts,” the report says.
The review team attributed the identified design concerns to several factors, including “inadequate design execution and control”; “inadequate” control system design; “inadequate implementation of ALARA principles”; and “inadequate consideration of maintenance and waste management requirements.” Other identified deficiencies, according to the report, include transfer of scope and risk to the commissioning phase of the facility and “throughput not adequately underpinned.” The report notes that many of the design issues had been identified in previous DOE and Bechtel National assessments. DOE Federal Project Director William Hamel told WC Monitor this week that approximately 15 percent of the issues identified in the design and operability review are considered to be new. DOE is also examining how to implement a recommendation from the review team to examine the remaining systems in the HLW Facility, Hamel said.
Bechtel Has Plans to Address Review’s Findings
Bechtel National is working to address the issues identified in the design and operability review. According to an action plan Bechtel National has developed, also released by DOE late this week, the contractor plans to take steps such as developing new engineering studies to “quantify additional requirements and operational demands on various WTP systems” and to conduct a throughput study to “assess maintenance requirements in the decontamination system in order to meet potentially increased demands.” Bechtel National also plans to “re-evaluate operability models to ensure that interfacing systems can manage the volume and configuration of the waste to be treated” and to “consider the need for additional equipment in some areas and assess the removal of unnecessary components,” the action plans says.
With the resumption of full production engineering, Bechtel National can move forward with design work to address the issues identified in the design and operability review. The action plans Bechtel National has developed for the vulnerabilities identified in the review allows the contractor to “to focus our effort, whether it be on the development of additional models to support the design or the review of the existing design for potential enhancements to support operation,” Daniel said. “Coming out of the design and operability review, we’ve identified the issues. We’ve identified the path forward for those issues. We have the agreement on the path forward, and we’re laying that into the schedule for when that activity will be completed.” He added, “As part of our enhancements and what we’re moving forward with, we’re actually looking at a system engineering approach. So we’re going to be evaluating the design in a system by system aspect. We’re currently laying out that schedule and putting information together for what activities will be done for each system and when those will be completed.”
Review, Action Plan Will Help Develop Facility Schedule, DOE Says
DOE’s Hamel said the action plans Bechtel National has developed will aid in the preparation of a schedule for completing work at the HLW Facility. When asked when such a schedule is expected to be completed, though, Hamel said, “The design and operability review and they key results from it and the actions we’re taking are all critical to informing the schedule and the path forward. … We have to perform all of those activities before I answer that with a date. Those are key activities that are needed to inform the schedule and the path forward and they tie into some of the technical issue resolution.”
When asked how long it will take Bechtel National to complete the actions in its plan, Hamel said, “The actions vary in length depending on the complexity of the actions. Some of the actions we expect to be taken in the near-term. Some of those are going to be long-term. And as we get further into those actions, we’ll be able to define the durations better.”
Does DOE Need an ‘Owner’s Rep’ at WTP?
The design and operability review also recommended that DOE look to establish an independent owner’s representative that would report directly to the Department and have the authority to “challenge the facility design when operability and facility life-cycle risks are evident.” The report says, “A fundamental concern is the lack of focus on the long-term operability and sustainability of the facility. There is currently no organization, independent of the project, reporting directly to DOE with the necessary technical skills, experience, responsibility, accountability, and authority to impact these generally longer term issues.”
DOE is considering “the best way” to implement the recommendation, Hamel said. “Quite frankly, we’ve actually implemented that in a way—this design and operability review was done by independent experts that we brought in. So that is an application of the same concept. We don’t necessarily call it the owner’s rep, but the application and the principal are the same—having an independent look during the design review process,” he said. “One of the values of having multiple ways of doing it is you bring in different types of expertise when you’re doing different activities. If I were to do a design review as the owner’s rep in another system or another area, I might want a different cadre of folks because they bring different expertise. So if I have a dedicated team, I may limit my options.”
When asked about the owner’s representative proposal, Bechtel National’s McCullough said, “They [DOE] have to assure themselves, as we have assure ourselves, that the design is meeting the requirements of the contract. On any project, not just WTP but on any project, you do get to a point where a better idea not placed at the right point in time, is not really a better idea. So as we conduct these reviews with off-site personnel, you have to be careful that we’re not revisiting something that is going to work.” She added, “The bottom line is we’re trying to remove vulnerabilities that might cause a problem in operations. But even in the simplest of jobs, the closer you get to completion, you have to be very careful about what you introduce as new ideas.”
