Document OzpLgLLjE3KkNEbEZk59bV85M

DownloadRandom document
I * EH-1027 ^CV- -' \ E. I. DU FONT DE NEMOURS S COMPANY 1 ifcoiwQAATxa V/1LMINGTON, DELAWARE 19898 ENGINEERING DEPARTMENT July 24, 1981 AR226-2140 CC; A.R. Behnke -PPS-Wasbington Wics A.C. Buston -PPS-Washington Hks P. Thistleton-PTO-Washington Wics H.L. Brooks -BSD E.H. Helmers BSD I.C. 13-AQ&BE J. G. I.OSCHIA2Q------ POL-niEK. PRODUCTS DEPAKniEMT WASHIHGTOH WOKSS PPD - WASHINGTON WOBKS - TCTLON ABB. POU.UTIOB GROUND LEVEL C-8 COMCEHTBAa'IOHS In your April 24, 1981 letter to me you requested determination of eight-hour emissions froia the TFE Building time -weighted (162) PEP C-8 concentrations that result Building (163). Subsequent to from that letter we elected to evaluate both and maximum eight-hour and annual mean I C~8 concentrations using five two cases for the n?E years of emissions. hourly meteorology 1 is found in for Parkersburg. examined your April 24 letter as "After May Shutdown" and Case 1A is . Case the same as Case 1 except the two dryer Vent stacks are 15 ft lower, representing the situation before the stacks were extended. Superimposed on the TPE dryer vents were C-8 emissions .from the baghouse FEP area. vents) are Basic sum data for these two vents (wet finishing and eoagulator Behnke dated Hay 21, 1981. I did not include marized in a letter to me from A. R. the blender pit exhaust because C-8 emission is negligible compared to the other Behnke *s ^ sources.' As you suggested, I used 50X of the emission, rates in A. R. Sg letter for this study. o Stack and emission data for both eight-hour and annual data mean concentrations cover the five-year ate period ^ o listed in Attachment '1973 A (four pages). to December 31, Meteorology 1977. Surface data are for Tarkersburg and o from January 1, mixing heights from Dayton, OH. Concentrations are computed for each hour and periods at each receptor (a point in space tfhoernwahvicehragceodncoevnetrraetiiognht-ihsoucor mapnudteadn).nuaAl ll eight-hour ttoe weighted AEL of averages for 10 g/m3. the entire five-year period are below the Haskell Laboratory Tour May 12. 1981 letter to me specified 15 locations for which eight-hour and annual Table 1 is a sinamary of the highest" calcu mean concentrations were lated C-8 concentrations to be computed. for each of these 15 locations over the five-year period of stack heights record for Case 1 and Case 1A. To reiterate. stack heights prior to Case 1 represents current extension of the dryer vent stacks on and the Case 1A represents TFE Building. The highest calculated eight-hour value is 6.9 ug/m3, at the Butacite Office Building (Case 1A). EID079585 -2- . July 24, 1981 ; J. G. Loschiavo Table 2 is a summary of the highest- one-hour concentrations for each receptor location for each of the five years. Although there 'is no established one-hour Idhnit for C~8, the one-hour values need to be calculated to determine eight-hour and annual -mean concentrations. The highest eight-hour values are summarized in. Table 3. Hone of the values ex ceeds the Alii, of 10 ug/m3. Comparison with Table 1 indicates that maximum eighthour values are less than half the maximum one-hour values. This is due, of course, to the improbability of identical meteorological conditions persisting from hour to hour. Annual mean values for each of the five years are summarized in Table 4. There is no annual mean limit for C-8 but annual values at a given location determine long term exposure to C-8 and, as suggested by Paul Thistleton, may be useful in corre lating with organic fluoride blood analyses done on selected plant employees. Hone of the 15 receptors (except possibly Ho. 15) is downwind of the prevailing (W to SW) wind direction. "For this reason, I have made. additional annual mean . determinations for a receptor grid of 2400 receptor points located 200 ft apart. .Maximum annual values for these, runs are summarized in Table 5. As expected, the maximum values are somewhat higher than those determined from the 15 receptor plant network. Concentration contours for 1976, the year which exhibits the highest annual values, are drawn on figures 1 and 2. The maximTM concentrations, as expected, fall to the northeast of .the plant. The highest calculated eight-hour "concentrations, .for Case 1 and Case 1A, occur ac Butacite Office Building on June 4, 1977 from 8:00 AM to 4:00 TM. I have computed concentration contours for this period and have attached then'as Figures 3 and 4. These contours represent concentrations at a 2400 point receptor grid with the points 50 ft. apart. Meteorological conditions for the critical eight-hour period are listed in Attachment B. Please note that "ground zero" for all of the concentration plots is a point half way between the dryer stacks. I have only plotted "worst case" conditions; other periods can be easily plotted if you so desire. ENGINEEKJKG SERVICE DIVISION Air Quality & Hazards Engineering Kle^. B.. I. Wevodau Senior Consultant RIW:cpr Attach. EID079586