Document vVa7mpqDve9916EMg42j7yMoR

Lake Charles VCM Plant CERTIFIED MAIL #8651413 RETURN RECEIPT REQUESTED Conoco Chemicals Company A Division of Conoco Inc. P. O. Box 605 Westlake, Louisiana 70669 (318) 491-5211 May 11, 1982 Myron Knudson Water Management Division Environmental Protection Agency, Region VI First International Building 1201 Elm Street Dallas, TX 75270 Dear Mr. Knudson: In accordance with the conditions of the Conoco Chemicals Company VCM Plant's NPDES Permit No. LA0003476, we are informing your office that a partial by-pass of the waste water secondary treatment system occurred on May 6, 1982, and again on May 7, 1982. The partial by-passes occurred at the flood control box for 35 minutes on May 6 and for eight hours and forty minutes on May 7 after a continuous rainfall of 1.37 inches on May 6 and 0.53 inches on May 7 as recorded by the National Weather Service at Lake Charles Municipal Airport. However, local flooding in Westlake indicated that a much heavier rainfall occurred at the VCM Plant. The partial by-pass on May 6 occurred from 12:30 pm to 1 :10 pm and the by-pass on May 7 occurred from midnight to 8:40 am. As required by our NPDES Permit, a grab sample of the partial by-pass was collected. Only one sample was collected on May 6 since the by-pass lasted less than one hour. Samples were collected every hour for the May 7 by-pass and were combined to form a composite sample. Effluent characteristics of the partial by-passes are as follows: May 6 Flow BOD COD TSS Ammonia Chlorinated Hydrocarbons (As Ethylene Dichloride) PPM MU 61 231 .225 37 Lbs. 9343 (i) .570 2.16 .002 .346 Myron Knudson Page 2 May 7 FI ow Bod COD TSS Ammonia Chlorinated Hydrocarbons (As Ethylene Dichloride) PPM _ (i) 193 697 .135 112 Lbs. 4,087 di 789 2849 .551 458 (1) Five-day BOD analyses are not yet complete. There has been no visible impact to the receiving waters as a result of the by-pass. As can be seen in the description of the non-compliance, the discharge of all parameters except for Total Suspended Solids on the May 7 by-pass was less than the values allowed by our NPDES Permit. We will send the results of the BOD analyses to you when they are completed. Should further information be required, please contact Ron Bryan, Chief Process Engineer at (318) 491-5062. Sincerely, Plant Manager Conoco VCM br cc: J, Dale Givens - DNR CRH^MGH-BIR-RB-PL^-DLi/jWW-ja-SW^ OCR 000067253