Document n9jx2o8mVNpXD6Y7gRRYbbQvX
AR226-2155
C atherine A Barton
j j 08/27/2001 03:24 PM
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To: Debbie J MuIrooney/AE/DuPont@ DuPont, Robert F Pinehot/DEV/AE/DuPont DuPont cc: Catherine A Bartan/AE/DuPorrt@ DuPont Subject: Recap of our meeting
Just s o w e're on the sam e p age (and so l can rem em ber w hat w e sa id we'd do a w eek from now), I've sum m arized som e notes from our meeting today. If any of this looks incorrect to either o f you, please holler.
A ir R isk
Debbie will run an additional air dispersion m odeling c a se ("C a se 5 ") to represent the follow ing
conditions:
Release rate = 0.03 g/s
-
Stack flow rate = 10,000 scfm
Stack Velocity = 1 0 0 ft/s 2o,S
Stack Height = 85 ft
Building Height = 5 5 ft
Temperature = 298 K
W e will com pare the C a se 5 concentration results to the C E G for air of 0.3 ug/m3 to ensure these
d esign conditions meet our guidelines with a "reasonable level of comfort".
D rin k in g W ater R isk Debbie will p a ss along the input fife to Cathie to be run in risk m ode at 1 g/s to provide revised input
for deposition calculations. Cathie will explore the ulitmate fate of all the e m issio n s leaving the stack (ie, 0.03 g/sec for a year
w hich equals 2 08 6 Ibs/yr by m y calculations). Specifically, w e would like to be able to create a m ass balance of all the com pound leaving the stack. Cathie will validate her assum ptions about the appropriate annual deposition rates and w atershed surface area and finalize her calculations. W e will com pare the new water concentration results to the C E G for water of either 1 ug/I o r 3 ug/l, depending on results from the air exposure to ensure the d e sign conditions meet ou r drinking water guidelines with a "reasonable level of comfort".
F ish R isk U sing the water concentration calculated above, a B C F of 10, and fish consum ption rates
recom m ended b y the Environm ental Factors handbook, Cathie will com pare expected d o se s from fish
consum ption with our guideline of 7 3 0 ug/yr.
F in a l Fayetteville A n sw e r W e will provide final verbal answ ers for air and water risk by Ju ly 11, with the report following.
W ash in gto n W o rk s W e will provide a rough scope and estimate for the new w ork that w as d iscu sse d by July 9.
DJM 000275 EX D 502517