Document x5Lg8RdpYOzKa93xaDNzJEd01

E N - 1027 f r c V - 7 .7 0 mm gaiuttonot E. I. DU Pont de N emours & Company IN CM PO M TO Wilmington, Delaware 19898 en gin eerin g departm ent July 24, 1981 -- AR226-2140 CG: A.R. Behnke -FFD-wasnongton A.C. Huston -PPD-Washington Wks P* Thistleton-PPD-Washington Wks . H. L. Brooks -ESD ; E.N. Helmers ESD I. C. 13-AQ&HE . J. G. L0SCHIA2-- ---. POLMES. PRODUCTS DEPARTMENT WASHINGTON WORKS PPD - WASHINGTON WORKS - TEFLON ALB. POLLUTION GROUND LEVEL C-8 CONCENTRATIONS yt . J-, oa iqoi letter to me you requested determination of eight-hour In your April 24, 1981 letter t from emissions from the TFE Building time weighted C-8 concentrations letter we elected to evaluate (162) and FEP Building (163).. Subsequent ^ ^ atioos using five years of both maximum e^ " ^ p ^ e" g. I examined two cases for the TFE emissions, hourly meteorology for Parkersburg. "After May Shutdown" and Case 1A is Case 1 is found in your April _ stacks are 15 ft lower, representing the same as Case 1 except the two dryer vent stacks are it j. , r the situation before the stacks were extended. srgrLrTM%SL%t t s s ss*.,, , ... TFE drver vents were C-8 emissions from the FEP area. Basic naxlzed In a letter to me from A. - ^ negligible compared to the other letter for this study. Stack and emission data for both eight-hour and annual Period listed in Attachment A lor Srkersburg and from January 1 , 1973 to December 31, 19 ng are computed or each hour and t t S Z Z Z & t t ' A t^MoS-or, - 10 lour Hap 12. 1081 letter to me ep.clflad mean concentrations were b* 15 l o L S o n s over the five-year period of lated C-8 concentrations b r e a c h of these 15 repreSents current stack heights record for Case 1 and Case 1A. To reiterate, Cas P, , - vent stacks on and Case 1A represents stack heights prior ^ p e n s i o n of " the TFE Building. The highest calculated eight-hour value is b-Y jig/ . Butacite Office Building (Case 1A). AJP002900 EID079585 2- - July 24, 1981 J. G. Loschiavo Table 2 is a summary of the highest-one-hour oncentrations for each receptor location for each of the five years-. Although there 'is no established one-hour limit 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. None of the values ex ceeds the AEL of 10 jig/m^. Comparison with Table 1 indicates that maximum eighthour values are less than half the maximum one-hour values. This is due, of course, to th improbability of identical meteorological conditions persisting from hour to hour. Armnai 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. None of the 15 receptors (except possibly No. 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 T.able 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 maximum concentrations, as expected, fall to the northeast of the plant. ,, The highest calculated eight-hour concentrations,.for Case 1 and Case 1A, occur at Butacite Office Building on June 4, 1977 from 8:00 AM to 4:00 PM. I have computed concentration contours for this period and have attached them 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 dsire. ENGINEERING SERVICE DIVISION Air Quality & Hazards Engineering R. I. Wevodau Senior Consultant R I W :cpr Attach. ' AJP002901 EID079586