Document 6RdvmkxvBGp0RbV7dxJyJ3xQ3

4r* 226-2047 Roger J Zipfel 07/27/2001 01:30 PM To: John E Crum/SE/DuPont@DuPont cc: Ta-W ei Fu/CL/DuPont@DuPont Subject Re: C-8 sampling Q John, this is very perplexing information. I don't in anyway believe this is coming from any liquid solutions of C -8 in B-124. Ron runs a pretty tight ship and there is minimal C -8 laying around. W hat is happening is that we are not abating the vent from the fine powder scrubbers. This plume of C -8 must be entering the recovery building. W e find high levels of C -8 on the roof areas of B-162, levels above the AEL. ` | believe this situation will disappear when we get our exhaust filters on line. Prior to that we could do an extensive study to verify one source vs. another. Again I don't think this is coming from any aqueous leaks. Thus your concern is not the main concern relative to this issue. Roger. John E Crum John E Crum 07/27/2001 07:54 AM To: Ta-W ei Fu/CL/DuPont@DuPont, Roger J Zipfal/AE/DuPont@DuPont cc: Subject: C-8 sampling Please note the attached. T h e samples seem to be consistantly on the high side. I would like to understand what is causing this? Ta-W ei you inidicated it must be from dry powder over the phone yesterday because of the high vapor pressure of C-8, but somehow I remember in the old days of us saying that C -8 azeotroped with water in the dryer and that we needed w ater in order to help remove the C-8 from the polymer. Otherwise the dryer could not "evaporate" C-8 and it would remain with the polymer. M y concern is the extra exposures that will occur with the new RO unitsll W e will be releasing a lot more dilute C -8 liquids to the floor area in the building and determine if this is coming from vapor concentrations rather than particle concentrations. Dried C-8 particles can be kept to a minimum by hosing down the floor well, but we will have difficulty in keeping vapor concentrations down. And whether this is from the present units or new units, I would assume that having this restriction is going to be a long term problem/concern that we m ay want to deal with. Can we live with having a 15 min exposure limit in the room for the long term? - ----------------- -------------Forwarded by John E Crum/SE/DuPont on 07/27/2001 07:34 A M ---------------------------------------- ( if Donald E McKown ' 07/26/2001 05:03 PM To: John E Crum/SE/DuPont@DuPont, John S Haminond/HO/DuPont@DuPont cc: Subject: C-8 sampling - Forwarded by Donald E McKown/SE/DuPont on 07/26/2001 05:03 P M ------ Jack L Offenberger 07/26/2001 01:21 PM EID339020 To: cc: Subject: James W Hunt/CL/DuPont@DuPont Donald E McKown/SE/DuPont@DuPont, Becky Szakats Dines/CL/DuPont@DuPoni, Nicholas K Raed/AE/DuPont@DuPont, Mark D Cothern/SE/DuPont@DuPont, Anthony J P!aytis/CL/DuPont@DuPont, Fred M Lentz/SE/DuPont@DuPont C-8 sampling W e have had some complaints regarding the posted signs in the C-8 Recovery building requiring Respiratory Protection while working in the building over a 15 minutes tim e frame. W e have done some extra sampling in the building to see if the levels are low enough to remove the signs. Below are the results of the most recent sampling. DATE 7/3 7/20 7/20 7/24 7/24 RESULT 0.31 0.52 0.46 0.48 0.52 % of AEL 55.4 92.9 82.1 85.7 92.9 Sam ple Routine sample Extra Sampling Extra Sampling Extra Sampling Extra Sampling Out of the last 2 5 samples taken in that area, 4 have been over the AEL, another 13 have been well over 1/2 of the AEL and 8 were less than 1/2 the AEL. Should we continue with the extra sampling? Based on these results, l lean towards keeping the respiratory protection requirement. Thanks -J a c k Offenberger, Teflon S &O H Coordinator ext. 4959 EID339021