Document M5bLO04npoKL2jZZBxGrXRqz

ABD00266994 To: JEN Interoffice Communication From: Date: Subject: M. G. McCollum January 5, 1993 RELEASE MODELING - RUPTURED VCM RAILCAR VIS1A Following are the results from the initial rail car modeling case. Assumptions made and methods used are detailed below and in the basis memo dated 12/30/92. Stability Class Cone. (ppm) Isopleth Dimensions (ft) Length Width 1 D 5 14,436 1,312 2 D 1,000 574 66 3 D 18,000 - - 4 F 5 49,212 1,837 5 F 1,000 1,247 66 6 F 18,000 - - DESIGN BASIS Total release of VCM rail car (180 M lbs) over a two hour period. ASSUMPTIONS/METHOD Due to limitations of SPILLS, the release was modeled as an instantaneous release that forms a 100 m2 pool of liquid. The model calculates the evaporation time as 610 minutes. The isopleths are stable only in steady state conditions. The closest approach to steady state should occur immediately before the VCM totally evaporates. The plume dimensions above occur 6 hours after the release. Assume there was no fire. <2<l\ -*TL