2
Technical Risk Assessment Issues

The Bechtel Parsons Blue Grass Team recognized the technological challenges involved in designing and integrating a new process. To address them, an integrated product team (IPT) was organized to define the set of unit operations that would best meet requirements for the Blue Grass Chemical Agent Destruction Pilot Plant (BGCAPP). This proposed design is described in the Design-Build Plan (DBP) for BGCAPP (Bechtel Parsons, 2003). Although the selection process was subjective, it drew on lessons learned from the chemical agent disposal facilities at Johnston Island; Tooele, Utah; Aberdeen, Maryland; and Newport, Indiana, and on expertise from the earlier Assembled Chemical Weapons Assessment program.

As the proposed BGCAPP design was being refined, the IPT recognized that there were technical risks and thus performed a technical risk assessment (TRA) of the proposed design concept. The stated purpose of the TRA was “to mitigate the technical risks associated with operations that have not yet been demonstrated at full scale” (Bechtel Parsons, 2003, p. 8-9). Also, it was noted in the DBP, Section 8.2, that “although these risks are intimately connected with safety, they are primarily schedule and cost oriented” (Bechtel Parsons, 2003, p. 8-8).

In accordance with AR-385-61 and DA PAM 385-61, the Bechtel Parsons Blue Grass Team prepared and implemented a system safety management program (SSMP) at the start of design. Detailed safety analyses of all areas of the process are being conducted as the initial designs are developed, and the findings of these analyses are fed back to the designers and tracked to a resolution that satisfies worker and public safety. This program will continue to exist throughout the entire design, construction, operation, and closure of BGCAPP. The SSMP is separate from the technical risk assessment, which is focused on obtaining the best possible design using the selected technologies. Members of the safety analysis team responsible for the SSMP take part in the technical risk assessment to assure that safety issues are being addressed as solutions to risk issues are considered.

The IPT TRA team consisted of permanent core members and ad hoc members selected for their expertise on specific subject matter. The membership was drawn from Bechtel and Parsons personnel having expertise in all aspects of the operation of chemical plants and, particularly, chemical agent destruction facilities. Additionally, Assembled Chemical Weapons Alternatives (ACWA) program staff and supporting contractors participated. However, the Bechtel Parsons team chose not to invite the public to participate in the IPT because it believed that the IPT was an internal contractor activity and the public did not have the technical expertise to understand the issues.

The TRA process is intended to be continued and refined throughout the life of the BGCAPP project, at each stage of the project life cycle. To prioritize the risks, the IPT adopted a semiquantitative approach, assigning individual weighting factors to “probability of occurrence” and “technical, schedule, and cost consequence of occurrence.” The probability and consequence weighting factors are summarized in Table 2-1. As shown in the table, the weight for each technical



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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant 2 Technical Risk Assessment Issues The Bechtel Parsons Blue Grass Team recognized the technological challenges involved in designing and integrating a new process. To address them, an integrated product team (IPT) was organized to define the set of unit operations that would best meet requirements for the Blue Grass Chemical Agent Destruction Pilot Plant (BGCAPP). This proposed design is described in the Design-Build Plan (DBP) for BGCAPP (Bechtel Parsons, 2003). Although the selection process was subjective, it drew on lessons learned from the chemical agent disposal facilities at Johnston Island; Tooele, Utah; Aberdeen, Maryland; and Newport, Indiana, and on expertise from the earlier Assembled Chemical Weapons Assessment program. As the proposed BGCAPP design was being refined, the IPT recognized that there were technical risks and thus performed a technical risk assessment (TRA) of the proposed design concept. The stated purpose of the TRA was “to mitigate the technical risks associated with operations that have not yet been demonstrated at full scale” (Bechtel Parsons, 2003, p. 8-9). Also, it was noted in the DBP, Section 8.2, that “although these risks are intimately connected with safety, they are primarily schedule and cost oriented” (Bechtel Parsons, 2003, p. 8-8). In accordance with AR-385-61 and DA PAM 385-61, the Bechtel Parsons Blue Grass Team prepared and implemented a system safety management program (SSMP) at the start of design. Detailed safety analyses of all areas of the process are being conducted as the initial designs are developed, and the findings of these analyses are fed back to the designers and tracked to a resolution that satisfies worker and public safety. This program will continue to exist throughout the entire design, construction, operation, and closure of BGCAPP. The SSMP is separate from the technical risk assessment, which is focused on obtaining the best possible design using the selected technologies. Members of the safety analysis team responsible for the SSMP take part in the technical risk assessment to assure that safety issues are being addressed as solutions to risk issues are considered. The IPT TRA team consisted of permanent core members and ad hoc members selected for their expertise on specific subject matter. The membership was drawn from Bechtel and Parsons personnel having expertise in all aspects of the operation of chemical plants and, particularly, chemical agent destruction facilities. Additionally, Assembled Chemical Weapons Alternatives (ACWA) program staff and supporting contractors participated. However, the Bechtel Parsons team chose not to invite the public to participate in the IPT because it believed that the IPT was an internal contractor activity and the public did not have the technical expertise to understand the issues. The TRA process is intended to be continued and refined throughout the life of the BGCAPP project, at each stage of the project life cycle. To prioritize the risks, the IPT adopted a semiquantitative approach, assigning individual weighting factors to “probability of occurrence” and “technical, schedule, and cost consequence of occurrence.” The probability and consequence weighting factors are summarized in Table 2-1. As shown in the table, the weight for each technical

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant TABLE 2-1 Probability, Consequence, and Risk Weighting Factors for BGCAPP Design-Build Plan Technical Risk Assessment Probability of Occurrence Consequence of Occurrence Probability Description Weight of Probability Technical Schedule Cost Impact (%) Aggregated Weight of Consequence Remote 1 Minimal or no impact Minimal or no impact Minimal or no impact 0.2 Unlikely 2 Acceptable with some reduction in margin Additional resources required to be able to meet need dates <5 0.4 Likely 3 Acceptable with significant reduction in margin Minor slip in key milestones, not able to meet need dates 5-7 0.6 Highly likely 4 Acceptable with no margin Major slip in key milestones or critical path impacted 7-10 0.8 Nearly certain 5 Unacceptable Cannot achieve key team or major program milestone >10 1.0 NOTE: Risk ranking or weight = weight of probability × aggregated weight of consequence. SOURCE: Adapted from Bechtel Parsons, 2003. risk was calculated by multiplying the two weighting factors. For example, a probability weighting of 3 (the occurrence is likely) times an aggregated consequence weighting of 0.4 (technical, schedule, and cost consequences as described in Table 2-1) gives an overall risk weight of 1.2. Each of the risk weights was then assigned to one of three overall risk weight categories: low (overall weight less than 1.0), medium (overall weight between 1.0 and 3.0), and high (overall risk weight above 3.0). The committee believes that the basic approach has merit as a screening tool based on expert judgment (Bechtel Parsons, 2003). The IPT identified 89 technical risks relating to major unit operations. All risks were ranked on the basis of the risk weight expected after implementing proposed mitigation activities, because the IPT believed that this approach “would allow assessment of compound risks as well as monitoring of implementation of the proposed risk mitigation measures” (Bechtel Parsons, 2003, p. 8-7). No risks were identified with an overall weight of 3.0 or greater. Twenty-nine risks were identified with an overall risk weight between 1.0 and 3.0. The 89 identified risks are listed in Appendix P, Table P-1, of the BGCAPP DBP ((Bechtel Parsons, 2003) and in Appendix F of the BGCAPP TRA IPT Quarterly Reports). On the basis of the preliminary TRA, the design for construction, operation, and closure was modified, as appropriate. Also, several trade studies and prototype test programs were selected to be carried out during the design phase to reduce overall technical risk. These studies and test programs were designated as technical risk reduction projects (TRRPs) and have become the focus of major risk mitigation activities for BGCAPP.1 Subsequently, periodic reviews by the IPT TRA team during design had identified 24 additional items by July 2004.2 Some of these risks were designated to be addressed by TRRPs. The status of ongoing and completed TRRPs as of February 15, 2005, is shown in Table 2-2.3 1   The acronym TRRP has been used in various contexts to refer to either the overall technical risk reduction program that resulted from the technical risk assessment results, or (with a designation number, e.g., TRRP 7) to individual projects for mitigating specific identified risks. This report refers to the latter. 2   Technical Risk Assessment Integrated Product Team Quarterly Report, July 2004, prepared for the PMACWA. 3   February 15, 2005, represents the last time documented information on the design status was briefed to the committee by the PMACWA staff and the Bechtel Parsons Blue Grass Team. It therefore serves as a nominal cut-off date for information gathering on the status of TRRP projects for this report.

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant TABLE 2-2 Summary of Technical Risk Reduction Projects for BGCAPP as of February 15, 2005 TRRP No. Short Title Scope Status/Results 1 LPMD Machine (trade study) Redesign PMD machine to remove nose closure and burster in a linear series of stations (the baseline PMD used a series of stations set in a circle). Projectiles are to be disassembled in a vertical rather than horizontal position. Reduce congestion in ECR and possibly permit installation of redesigned PMD machine into the ECR after completion of VX campaign. Build on results of the PCAPP study. This TRRP activity has been completed and the results are being implemented. 2a GB Neutralization Analytical Methods (bench-scale test) Verify process design assumptions and validate the method detection limit (MDL). Analytical methods are being developed for measuring agent in the hydrolysate. The methods must be both reliable and fast enough to support throughput rate targets. This has not been demonstrated to date. If analysis turnaround times are too slow, additional storage capacity must be provided.     Evaluate hydrolysis of GB with caustic with a focus on verifying reaction stability at planned operating temperature of 194­°F with caustic solution (11.34 wt%).   The Test Protocol, Rev. 1, was reviewed by the TRRP IPT, and the test plan was being finalized. 2b H vs. HD Neutralization Analytical Methods (bench-scale test) Verify process design assumptions and validate analytical method for H. Compare with HD analytical method for PCAPP. This TRRP has been successfully completed. 3 Air Monitoring (bench-scale test) Conduct testing to demonstrate efficacy of air monitoring systems. Reduce potential for interferences, particularly with GB and VX hydrolysates. Build on experience from the Newport Chemical Agent Disposal Facility. Evaluate multiagent monitoring systems. This TRRP activity was in progress. 4 Energetic Hydrolysis Analytical Methods (bench-scale test) Confirm reaction conditions for energetics hydrolysis (heat, kinetics, duration of hydrolysis, product characterization, etc.) by lab/pilot tests. Provide data to support, design, and develop an analytical method to measure agent in hydrolysates during operations. The test program has been initiated. The test runs will commence when Battelle receives the necessary aluminum material and propellant material. Methods development was still in progress.

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant TRRP No. Short Title Scope Status/Results 5a Prototype MWS Testing (prototype test) Design and fabricate full-scale MWS line for GB/VX/H projectiles. Conduct a testing project to demonstrate the efficacy of the cavity access machine for 155-mm H and VX projectiles and 8-inch GB projectiles, all of which have operational requirements different from those of the projectiles that will be processed at PCAPP. During validation testing, a total of five trays (40 projectiles/tray) were processed at a throughput rate of 29 rounds/hr. Later off-line component tests conducted with the VX 155-mm projectiles showed that the burster wells of the test hardware used for the test were manufactured with seams. During the punch operation, the burster wells were observed to split along the seams, which could cause complications with the MWS punch/ washout operation. PMACWA has determined that the stockpile at Blue Grass Army Depot may have both seamed and unseamed burster wells, so the BGCAPP MWS needs to be designed to handle both types of burster wells. The Bechtel Parsons Blue Grass Team is currently evaluating some equipment modifications that may correct the problems observed. Systemization tests for the VX 155-mm projectiles have been completed.   Testing for heavier 8-inch projectiles was in progress. 5b-1 Prototype EBH/HDC Testing (prototype test) Perform tests of the prototype HDC to define final design parameters. HDC testing was in progress, and design changes were being investigated. 5b-1a Aluminum Filtration Tests (prototype test) Using hydrolysate from prior Tooele Army Depot tests of the ERH/EBH, perform tests to confirm the method for filtering aluminum hydroxide precipitate from the hydrolysate feed to SCWO units. General Atomics performed aluminum filtration tests with a belt filter press at a vendor’s facility using hydrolysate produced during the TRRP 5b-1. Early hydrolysis tests conducted for the prototype EBH with hydrolysate at pH values of 5.5 and 7.3 resulted in aluminum concentrations in the filtrate greater than 400 ppm (the maximum acceptable value to avoid SCWO reactor plugging as observed during previous PMACWA SCWO tests). Four additional aluminum filtration tests were performed at pH values of 7 or 8 and with different acids and additives to see if lower aluminum concentrations in the filtrate can be achieved. General Atomics was waiting for lab analyses of samples taken from these most recent filtration tests. 5b-2a EBH Full-Scale Testing (prototype test) Simulate full-scale EBH operation. Verify key mechanical features and interfaces of the EBH drum, including liquid fill, solids feed and discharge, spray bars for rinsing, chute design and jam-free operation, and liquid discharge at rates consistent with peak RSM operating rates. Also, demonstrate interface of EBH with feed hopper and discharge conveyor. Full-scale mock-up tests of the material handling and mechanical characteristics of the EBH have been completed. The tests employed simulated warhead and rocket segments and burster tubes and small parts such as those found in the fuze. The tests were conducted at ambient temperature with water rather than at operating temperature with caustic. 5b-2b EBH Material Handling Testing (prototype testing) Test material handling associated with handling solids remaining after treatment in the EBH operation. Includes solids conveyor and solids metering to the HDC. Mock-up tests were in progress.

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant TRRP No. Short Title Scope Status/Results 5c Prototype MPT Testing (prototype test) Evaluate the design of the full-scale MPT for PCAPP and complete testing. The PCAPP MPTs are 6 ft and 10 ft in diameter. Only the 6 ft diameter unit is being tested. Same sizes to be used at BGCAPP. Testing to verify the design parameters for projectiles has been performed, but problems were encountered and resolutions were not available at the time this report was prepared. Additional MPT testing by outside contractor on characterizing the thermal treatment and offgases from secondary and closure wastes has been scheduled. 5d Prototype RSM Washout Testing (prototype test) Evaluate various washout parameters using a transparent warhead filled with a gelled agent simulant. Demonstrate the punch, drain, and washout of the simulated gelled agent using a modified baseline system RSM punch-and-drain station. Tests have provided information to improve the design of the punch-and-drain probes and to minimize the occurrence of aluminum in propellant batches to the EBH. No determination of the amount of aluminum in the washout water was performed. Using 400-psi hot water introduced through two punch nozzles, the modified RSM successfully washed out the simulated crystallized agent material. This TRRP activity has been completed. 6 Reactor Material and Corrosion Study Select materials to be used for neutralization reactors. Hastelloy C-276 has been selected as the material for neutralization reactors even though H hydrolysis in water could result in 2 wt% HCl formation and corrosion rates >50 mils per year. Since the H campaign has the shortest processing schedule (3 months), the Bechtel Parsons Blue Grass Team considers such high corrosion rates tolerable, and vessels can be fabricated with appropriate corrosion allowance. Teflon-lined stainless steel vessels were considered and were the most cost effective but were dismissed as they would generate fluorinated hydrocarbons when heated in the MPT during closure. This TRRP activity suggests additional testing be done to determine the actual corrosion rates expected during neutralization. 7 SCWO Maintenance (trade study) Perform SCWO system predictive/preventive maintenance study to guide development of preventive maintenance schedule and improve plant availability. This TRRP activity has been completed and the results are being implemented. 8 Blended SCWO Feeds (prototype test) Blend agent hydrolysates with energetics hydrolysate for feed to SCWO. Reduces phosphate content of GB hydrolysates, mitigates corrosion problems, reduces liner replacements, and improves availability. This TRRP activity has been completed and the results are being implemented. 9 SCWO Pilot Test Conduct SCWO pilot testing. Validate scale-up factors and fill data gaps. This TRRP activity has been completed and the results are being implemented. 10 EBH Containment Room Design (trade study) Establish a conceptual design for the EBH rooms based on the expected explosive and propellant contents of the room under peak operating conditions and assumptions about the maximum credible event. Results from this TRRP trade study have been incorporated into the EBH room design.

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant TRRP No. Short Title Scope Status/Results 11 VX Hydrolysis Analytical Methods Test (bench-scale test) Develop and perform tests to establish VX hydrolysis process parameters, and establish an analytical methodology. This TRRP activity was initiated after the analytical methods developed for use at the Newport facility were no longer applicable for BGCAPP due to reductions in the initial VX feed concentrations (to 8 wt%) for VX hydrolysis at Newport. Although the feed concentration now in use at the Newport site, 16 wt%, is similar to that planned for BGCAPP, the Newport site must attain a 20 ppb level of VX in the hydrolysate, whereas BGCAPP, which will have secondary treatment of the hydrolysate, must attain a 160 ppb level for which the analytical method used has fewer steps and needs to be completed as quickly as possible to minimize hydrolysate storage requirements. At the time this report was prepared, the test protocol for an analytical method suitable for BGCAPP had been prepared for TRRP IPT review. 12 RSM Cutting Accuracy Testing (prototype test) Perform testing to provide recommendations to the design team regarding an improved rocket positioning system. The ability of the baseline RSM to accurately index a rocket within its shipping and firing tube has been estimated to be accurate within ±0.25 inch, provided the equipment has been properly systemized and maintained. Over time and use, this accuracy will drift and will require adjustments. Telescoping and shifting of the rocket during shearing does occur and has been noted in videos of shearing operations. In addition to shifting during shearing at the shear station, shifting of the rocket within its shipping firing tube has been observed during TRRP 5d testing of punch-and-drain operations. While at the RSM punch-and-drain station, the warhead within its shipping firing tube is clamped by both the front and back clamps of the station. Despite this clamping, the warhead has been consistently observed to shift 0.5 inch in either direction within the shipping firing tube if the drain punches are alternately cycled. To prevent this shifting during the punch-and-drain operation, the drain punches are extended to simultaneously create drain holes and to peg the warhead in place until after the vent punches have been extended. Test Plan, Rev. B, was being prepared, and a magnetic detector for finding the interface between the steel rocket motor case and the aluminum warhead was being developed as part of this TRRP activity. NOTE: EBH, energetics batch hydrolyzer; ECR, explosion containment room; ERH, energetics rotary hydrolyzer; HDC, heated discharge conveyor; LPMD, linear projectile/mortar disassembly (machine); MDL, method destruction limit; MPT, metal parts treater; MWS, munitions washout system; PCAPP, Pueblo Chemical Agent Destruction Pilot Plant; PMACWA, Program Manager, Assembled Chemical Weapons Alternatives; PMD, projectile/mortar disassembly; RSM, rocket shear machine; and SCWO, supercritical water oxidation.

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Interim Design Assessment for the Blue Grass Chemical Agent Destruction Pilot Plant Finding 2-1a. The implementation of the risk assessment methodology in the preliminary TRA for BGCAPP depends strongly on engineering judgment, even with the weighting system described in Table 2-1. Finding 2-1b. The IPT membership included only government personnel and persons selected by the BGCAPP contractor from among experts in chemical demilitarization. Members were selected to ensure that process efficacy, safety, and environmental concerns would be addressed. There was no participation by representatives of the general public in the vicinity of the Blue Grass site. Recommendation 2-1. The Bechtel Parsons Blue Grass Team should consider asking the Kentucky Citizens’ Advisory Commission if members of the general public would be interested in participating or observing any future evaluations, not necessarily to identify the risks but to provide independent perspectives on the assessment of risk after mitigation and to demonstrate the transparency of the BGCAPP design process to the public. The lay public often perceives risks differently than technical analysts. For example, the activist public preferred neutralization because they perceived that baseline incineration technology was riskier. The public perceives as important mainly those risks that relate to worker and public safety, whereas the Bechtel Parsons Blue Grass Team may see those risks as manageable and less of a challenge than other technical risks with greater probability of large cost and schedule impacts. Finding 2-2. Despite the qualitative nature of the TRA process, the committee believes that of the issues identified to date, the Bechtel Parsons Blue Grass Team has appropriately determined the main technical road-blocks requiring further study as technical risk reduction projects (TRRPs). TRRPs are under way to acquire design data for unit operations identified as having insufficient prior testing or operating experience, and studies have been undertaken to evaluate promising alternatives or to resolve design decisions for areas not requiring testing. The committee believes that other issues requiring study as TRRPs will probably be identified before the design is completed. Recommendation 2-2. The Bechtel Parsons Blue Grass team should continue the technical risk assessment process as a mechanism to uncover issues that require further testing or studies.