Risk Assessment and Management at Deseret Chemical Depot and the Tooele Chemical Agent Disposal Facility (1997) / Chapter Skim
Currently Skimming:
2 DESERET CHEMICAL DEPOT/TOOELE CHEMICAL AGENT DISPOSAL FACILITY SITE-SPECIFIC RISK ASSESSMENTS
2 DESERET CHEMICAL DEPOT/TOOELE CHEMICAL AGENT DISPOSAL FACILITY SITE-SPECIFIC RISK ASSESSMENTS
Pages 14-38
The Chapter Skim interface presents what we've algorithmically identified as the most significant single chunk of text within every page in the chapter.
Select key terms on the right to highlight them within pages of the chapter.
From page 14... ...
External risk-initiating events are events not associated with site operations, such as earthquakes, floods, lightning strikes, and airplane crashes. (Note that there are also external risks to the stockpile from war or sabotage, which are reportedly evaluated and managed by specific government agencies and are not considered in publicly available site-specific risk assessments.
|
From page 15... ...
The transportation of agents from storage to the destruction facility, the unpacking and disassembly of munitions and containment systems, and the actual agent destruction processes provide additional opportunities for agent releases caused by internal or external events. Like the stockpile risk, the predominant operational risks are associated with agent toxicity.
|
From page 16... ...
Because of their proximity to the stockpile and agent processing operations, workers are at risk from the acute lethal (and nonlethal) hazards associated with agent releases, regardless of the initiating event (an at-risk situation)
|
From page 17... ...
The TOCDF QRA estimates the risk to the public and to workers from accidental releases of chemical agent associated with all activities during storage at DCD and throughout the disposal process at the TOCDF. Activities associated with the disposal process include: 17 · munitions storage at DCD prior to disposal · munitions handling at DCD in preparation for transport to the disposal facility · transport of munitions to the disposal facility · the disposal processes The study includes all identified potential causes of release, except for intentional acts, such as sabotage.
|
From page 18... ...
Uncertainty analyses showing the possible range of results, which were presented only for the public risks, incorporate the types of uncertainty discussed in Appendix A All other risks were expressed as expected risk levels.
|
From page 19... ...
These deviations are called "initiators." As suggested by the 1993 NRC letter report (NRC, 1993b) , initiators considered in the DCD/TOCDF QRA include "internal" initiators, such as equipment failures and human errors, and "external" initiators, such as earthquakes, plant fires, floods, tornadoes, and aircraft crashes.
|
From page 20... ...
Army, 1996c. To illustrate the method, the top logic from the DCD/ TOCDF QRA fault tree for "Agent Spill during Shear Operation" is displayed in Figure 2-3, which has been extracted from an appendix of the QRA (U.S.
|
From page 21... ...
Quantifying Moc/e/ Parameters Data on equipment failures and human errors are collected from both industrial and CSDP experience and used as a basis for evaluating the likelihood of initiators as well as the likelihood of subsequent events leading to accidents and potential agent releases. The probability of accident sequences resulting in agent releases are then estimated based on the accident sequence model and the basic event data.
|
From page 22... ...
Consistent with EPA guidelines for screening-level risk assessments, an adult resident, a child resident, a subsistence fisher, and three different subsistence farmers were identified as likely receptors. The adult and child residents were considered to reside at the off-site point of maximum emissions impact.
|
From page 23... ...
ADDITIONAL REVIEW OF THE RISK ASSESSM ENTS In addition to the Stockpile Committee, other organizations have been involved in the review and guidance of the risk assessments. Quantitative Risk Assessment Three principal reviews were used throughout the development of the QRA: intraproject reviews, PMCD and TOCDF reviews, and independent external reviews.
|
From page 24... ...
This not only kept the QRA team analysts well informed of the status of the facilities and of ongoing activities, but also helped the PMCD and TOCDF staff understand the risks associated with the disposal processes and the significance of the risk assessments being done as early as possible in the project. /nc/epenc/ent Externa/ Reviews The PMCD also established the Expert Panel (see Appendix B)
|
From page 25... ...
Overall, earthquake initiated events account for 82 percent of the average public fatality risk associated with continued storage of the stockpile; of the 18 percent nonseismic public fatality risk, leaks of agent GB from ton containers account for 11 percent (Figure 2-4~. An aircraft crash into storage structures and the electromagnetic effects of lightning (which could cause a 25 ~ Lightning 4°/0 A *
|
From page 26... ...
i; I I I 1 11111 1 1 1 1 11111 ~ HI I 1 11111 "t I I I 11~4 1 1 1 1 1111 1 10 100 1,000 10,000 100,000 Public acute fatalities 1 in 1 ,000 1 in 1 0,000 1 in 1 00,000 1 in 1,000,000 1 in 10,000,000 1 in 100,000,000 1 in 1,000,000,000 FIGURE 2-5 Public acute fatality risk of DCD stockpile storage over 7.1 years of disposal processing. Source: Adapted from U.S.
|
From page 27... ...
By the end of the fifth campaign (GB ton containers nearly three years into disposal operations) , both the storage and the processing risk have essentially disappeared.
|
From page 28... ...
Operationa/ Risk to Workers Workers at the TOCDF, including all support and administrative staff located at the facility or in nearby buildings and munition handlers responsible for removing munitions from the stockpile and transporting them to the disposal facility, were included in the risk assessment. The study includes only worker risks associated with accidents involving agent releases.
|
From page 29... ...
With about 100 workers in this category, and assuming that most accidents cause a single fatality, the Continued storage, no processing 1 :GB Rockets and _ TO TOCDF processing risk Stockpile risk at DCD during TOCDF processing o.oo 1.00 2.00 3.00 4.00 5.00 6.00 7.00 8.00 Time from start of processing (years) FIGURE 2-8 Comparison of public risks during processing at DCD and TOCDF.
|
From page 30... ...
\ Overall Risk ~Acute Fatality Risk. The public risk of an acute fatal Seismic events 97.4°/0 FIGURE 2-10 Contributors to the average public fatality risk from processing at DCD and TOCDF.
|
From page 31... ...
The total expected public acute fatalities during the disposal operations is the summation of both the processing risk 1 in 10 1 in 100 1 in 1 ,000 1 in 1 0,000 1 in 1 00,000 1 in 1,000,000 1 in 10,000,000 1 in 100,000,000 1 in 1,000,000,000 FIGURE 2-12 Summary of mean public risk from storage and processing at DCD and TOCDF. Source: Adapted from U.S.
|
From page 32... ...
As anticipated, the risk decreases with distance from the site. Figure 2-14 shows how disposal processing risk profiles vary with distance from the site.
|
From page 33... ...
These are small risks in comparison with the acute fatality risk to the public associated with the facility. Health Risk Assessment To evaluate human health risks, both carcinogenic and noncarcinogenic health effects from chemical agents, metals, volatile and semivolatile products of incomplete combustion, and other combustion products were considered in the HRA screening risk assessment.
|
From page 34... ...
emission rates for each identified organic compound. Total organic carbon data were available for the metal parts furnace, the dunnage incinerator,
|
From page 35... ...
conditioning filter stack operating individually the combined stack (liquid incinerators, metal 35 TABLE 2-1 Summary of the Human Health RiskOverall Risk of Cancer for Combined TOCDF and CAMDS Disposal Operations Period of Operation Receptor 10 years 15 years 30 years Adult Resident Child Resident Fisher Farmer A Farmer B Farmer C < 1 x 10-6 < 3 x 10-6 < 5 x 10-8 < 8 x 10-6 < 1 X 10-7 <9x 10-6 <2x 10-6 < 3 x 10-6 < 5 x 10-8 < 8 x 10-6 < 1 X 10-7 < 1 X 10-5 <4x 10-6 < 3 x 10-6 < 7 x 10-8 < 8 x 10-6 <2x 10-7 < 1 X 10-5 Source: Adapted from Utah DSHW, 1996. parts furnace, and deactivation furnace system operating simultaneously)
|
From page 36... ...
This mean risk level can be interpreted as typical of the individual public fatality risk from an agent release because about half of the people in the RISK ASSESSMENT AND MANAGEMENT AT DCD AND THE TOCDF zone will have a somewhat higher risk and half will have a somewhat lower risk. Note that government property around the TOCDF provides at least a 2-km buffer zone.
|
From page 37... ...
Table 2-3 presents measures of public risk (expressed as the number of fatalities expected as the Processing Period Consequence 7.1 Years of Exposure to DCD Storage during Disposal Processing 7.1 Years of Exposure to Disposal Processing at the TOCDF Fatality from Agent Release Accidents Eventual Chance of Cancer as a Result of Exposure to Stack Emissions Public risk, 1.6 x 10-3 expected fatalities 2.4 x 10-6 risk of latent cancers Worker risk not estimated in QRA Not applicable Public risk, 1.6 x 10~ expected fatalities 2 x 10-8 expected cancers Disposal workers, 1.3 x 10-i expected fatalities Other workers, 6.6 x 10~ expected fatalities Not included in HRA Source: Adapted from U.S.
|
From page 38... ...
The HRA does not address public risk; thus the health risk from normal operations cannot be put into the same framework. The HRA sets a criterion for a "maximally-exposed person" but does not evaluate the number of individuals who might be exposed at that or lower levels.
|
Key Terms
This material may be derived from roughly machine-read images, and so is provided only to facilitate research.
More
information on Chapter Skim is available.