SNM holdup assessment of Los Alamos exhaust ducts. Final report
Fissile material holdup in glovebox and fume hood exhaust ducting has been quantified for all Los Alamos duct systems. Gamma-based, nondestructive measurements were used to quantify holdup. The measurements were performed during three measurement campaigns. The first campaign, Phase I, provided foot-by-foot, semiquantitative measurement data on all ducting. These data were used to identify ducting that required more accurate (quantitative) measurement. Of the 280 duct systems receiving Phase I measurements, 262 indicated less than 50 g of fissile holdup and 19 indicated fissile holdup of 50 or more grams. Seven duct systems were measured in a second campaign, called Series 1, Phase II. Holdup estimates on these ducts ranged from 421 g of {sup 235}U in a duct servicing a shut-down uranium-machining facility to 39 g of {sup 239}Pu in a duct servicing an active plutonium-processing facility. Measurements performed in the second campaign proved excessively laborious, so a third campaign was initiated that used more efficient instrumentation at some sacrifice in measurement quality. Holdup estimates for the 12 duct systems measured during this third campaign ranged from 70 g of {sup 235}U in a duct servicing analytical laboratories to 1 g of {sup 235}U and 1 g of {sup 239}Pu in a duct carrying exhaust air to a remote filter building. These quantitative holdup estimates support the conclusion made at the completion of the Phase I measurements that only ducts servicing shut-down uranium operations contain about 400 g of fissile holdup. No ventilation ducts at Los Alamos contain sufficient fissile material holdup to present a criticality safety concern.
- Research Organization:
- Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- W-7405-ENG-36
- OSTI ID:
- 10126202
- Report Number(s):
- LA-12700; ON: DE94007116; TRN: 94:004585
- Resource Relation:
- Other Information: PBD: Feb 1994
- Country of Publication:
- United States
- Language:
- English
Similar Records
SNM holdup measurements for Los Alamos exhaust ducts, Interim Phase 2 report
SNM holdup measurements for Los Alamos exhaust ducts, Phase 1 report
Related Subjects
FISSILE MATERIALS
NONDESTRUCTIVE ANALYSIS
DEPOSITION
GLOVEBOXES
EXHAUST SYSTEMS
FUME HOODS
DUCTS
SURFACE CONTAMINATION
LANL
NUCLEAR FACILITIES
SAFETY ANALYSIS
PROGRESS REPORT
URANIUM 235
PLUTONIUM 239
CRITICALITY
EXPERIMENTAL DATA
RADIATION DETECTORS
STATISTICS
054000
HEALTH AND SAFETY