Document 1QJVyypXa6n5bNR0aqjaj5L9o

Monsanto INDUSTRIAL CfiPWICALS company .oc.,,o, W. M. Mees - -------- . November 9, 1972 u.i.c. PCB's IN JFQ SEWERS MMMNei TO : J. F. Nemeth/A. E. Peterson 1760 ccR. E. Keller - TIB W. B. Papageorge - B2NK E. S. Tucker - T2F The following is a compilation of the PCB levels found in JFQ sewer samples since my memo to you on 2/29/72. These results have been previously reported by phone. Month ppb PCB detected MSD Clean Acid Det Limit March April May June July August September 37 17 2 4 3 6 46 18 9 5 18 3 3 7 8 2 2 1 1 1 1 Comparison of these results with 1971 results indicates the PCB levels in the JFQ sewers have been significantly decreased. The change over of the heat exchange systems to fluids containing no PCB's should lead to further decreases in the PCB levels in the sewers. The 1-10% PCB remaining in these systems could be a significant source of contamination for some time and might explain the variations in recent results. As the PCB levels in the sewers decrease, additional work on improved sampling techniques and analytical methods will be necessary if we wish to detect PCB's at the lower limits of the proposed regulations. W. H. Mees db I'M MV. M-M MQNS 030180