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For hazardous materials that did not have TPQ or TQ values but did have RQ values and
the quantity of material in the facility exceeded the RQ value, qualitative arguments dealing with
dispersibility and programmatic controls associated with the hazard were used to complete the
hazard evaluation. These types of hazardous materials, in general, only pose threats to the IW
andlor the environment and not to the CW or the public.
For hazardous materials with facility quantities in excess of specified TPQ or TQ values,
a quantitative evaluation of accidental releases of the material was performed. Determinations
were made of chemical concentrations at the CW and MOI receptor locations using
Site-accepted chemical dispersion modeling tools as identified in the SARAH (Ref. 9). There
were no hazardous materials in the Building 991 Complex exceeding specified TPQ or TQ
values.
For immediate worker consequences, a qualitative judgment of acute toxicological
effects was made. Scenario related effects (e.g., burns from fires, injuries from energetic events)
were discussed in the accident scenario summaries but were not included in the determination of
the scenario risk class.
Toxicological consequences corresponding to the High, Moderate, and Low consequence
bins identified in Table4-1 are defmed by the comparison criteria developed in
DOE-STD-3011-94 and shown in Table 4-3. Toxicological consequence bin thresholds for the
MOI and CW are defined in terms of Emergency Response Planning GuideZine (ERPG) values,
published by the American Industrial Hygiene Association (Ref 18). These guidelines include a set
of thr& numbers (ERPG-1, ERPG-2, and ERPG-3) that qt,anW the air concentrations for each
chemical, corresponding to low, moderate, and severe health effects in humans exposed to the
chemical concentration up to one hour. The “up to one hour” guideline in the defmition of ERPGs is
interpreted to mean “peak 15-minute average” by the Energy Facility Contractors Group (EFCOG)
Non-radiological Hazardous Materials Safety Analysis Subgroup. Concentrations of the various
chemicals are calculated at the receptor locations and compared to the assigned ERPG values (or
alternative values) in order to determine a consequence bin assignment in accordance with Table 4-3
The Toxc Chemical Hazard CIm@ztion and Risk Accep-e Guidelines for Use in DOE
Facilties (Ref. 19) discusses alternative standards for cases where no ERPG value has been assigned
As stated above, toxicological consequences for the IW are determined qualitatively; therefore,
the toxicologkal consequence bin thresholds for the lW are defmed qualitatively.
Revision
September 1999
4-10
Building 991 Complex FSAR
I