Document 8rrEnwKne6qV2prjkQY6BB6Z

PPG INDUSTRIES, INC. INDUSTRIAL CHEMICAL DIVISION P. 0. BOX 1000 June 25, 1982 LAKE CHARLES. LA 70602 Mr. M. S. Ramesh Enforcement Division U. S. EPA, Region VI 1201 Elm Street Dallas, TX 75270 Dear Mr. Ramesh: Summarized below is the information you requested by telephone on 6/21 concerning the C1HC by-pass of 5/13/82, the lead by-pass of 5/18/82, and the deficiencies noted by t_hp DNR's NPDFS inspprtion of 4/6-7/82. Hopefully, these responses will answer your questions. C1HC As previously reported, the by-pass of process wastewater containing C1HCwas the result of an increase beyond capacity of flow through our wastewater treatment system (steam stripping). This was due to a combination of factors, principally to heavy rainfall and an abnormal water flow from our VCM-II operating unit resulting from a fire in that plant. The wastewater treatment system's surge capacity is provided by a surge pond which is 150' x 210' x 6', or 1.4 million gallons in volume. The system is designed to hold (under normal operating situations) the l-in-25-year maximum 24-hour rainfall of 15.67 inches, or 0.65 inches/hour. The maximum processing rate from the system is 1,000 - 1,100 gpnr, during normal (no rain) operating conditions, the system flowrate is between 700 - 800 gpm. The surge pond level is normally maintained between 1.5 - 2.5 feet which provides an approximate four-foot freeboard. When the rains began on 5/13, the surge pond level was already abnormally high (4'4") due to down time which had been taken on the steam stripping unit for necessary maintenance. Both strippers were out of service for repairs on 5/10, which resulted in the surge pond level rising from r6" to 5'4" on the morning of 5/11. Both strippers were placed back in service on the 11th, operated at full rates, and the pond level decreased to 3'10" by the end of the day 5/12. On the morning of 5/13, one steam stripper was again taken out of service for maintenance. Ordinarily, this maintenance work would have been delayed until the pond level was further reduced. However, due to the impending expiration of PPG's labor contract on 5/15, and the possibility of a strike, there was a need to complete the necessary repairs prior to 5/15. With one stripper down, the pond level began to rise again. The rate of increase was aggravated by an above-normal flow rate into the pond due to other maintenance outages in the organics area on 5/13. At noon, the last reading before heavy thunderstorms erupted 023258 ST- Mr. M. S. Ramesh June 25, 1982 Page 3 NPDES Inspection Concerning your questions on the DNR-conductcd NPDES inspection of 4/6-7/82, the deficiency of the Laboratory in failing to keep records of calibration and maintenance of lab equipment has been corrected. The Laboratory is now recording all calibration and maintenance activity. On the deficiency noted concerning the 10% error in flow on Outfall 010 and MB, we are presently reviewing our flow calculation methods with those cited by the OMR in the ISCO Open Channel Flow Measurement Handbook. We will begin using the ISCO Handbook if the difference between the two methods is significant. The third deficiency noted was inadequate refrigeration of TSS composite samplers on Outfalls 018, 019, and 017. New refrigerators were installed on these outfalls on 4/7/82. The last deficiency was concerning PPG's quality control procedures not being up to the 10% required by EPA. Per our conversation, our Laboratory has made contact with EPA, Region VI Quality Control people in order to work out what quality control is acceptabl If further information is required on any of the above sections, please let me know. Respectful 1 WJP:ap WILLIAM J. PEARD Fianagcr Environmental Control SL 023259