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DISINFECTION BYPRODUCTS HISTORY SUMMARY - MARTINSVILLE WTP <br /> <br />11/3/03 Rec'd notice from VDH that because of a high analysis for haloacetic <br />acids (HAA5s) for samples collected in late September, the four quarter rolling average <br />through the third quarter of'03 would be 0.072 mg/L, above the limit of 0.060 mg/L. <br />Historically, second and third quarter results have been higher than fourth and first <br />quarter, presumably because of higher water temperatures. <br /> <br />All prior testing for HAA5 had been within compliance levels since a compliance limit <br />became effective in December 2001. The September test result for Total Trihalomethans <br />(TTHMs) was also higher than normal, but the four-quarter rolling average remained <br />within compliance levels. <br /> <br />11/25/03 Reported to Council that VDH required public notices would be mailed to <br />all water customers within a week, and that a consukant (Dewberry in Danville) had been <br />hired to perform studies and make corrective recommendations at a cost of approximately <br />$17,000. <br /> <br />3/3/04 Rec'd notice that even though the HAA5 result for fourth quarter (results <br />late because of a lab problem) was 0.060 mg/L, the rolling average was 0.076, requiring <br />another public notice. <br /> <br />3/15/04 Switched from conventional Alum to Acidized Alum in an attempt to alter <br />process pH and improve removal of offending organics. <br /> <br />3/23/04 Again reported to Council that VDH required public notices would be <br />mailed within a week. Also noted that preliminary recommendations had been received <br />fi:om consukants. <br /> <br />3/30/04 Rec'd final report from Dewberry, including three basic <br />recommendations: (1) Install a Permanganate feed system at the Reservoir pump station; <br />(2) Relocate the chlorine injection point at the WTP; (3) Convert coagulant from Alum to <br />Ferric Sulfate. <br /> <br />3/31/04 Met in Danville with VDH and consultants to review report <br />recommendations. <br /> <br />5/19/04 Rec'd notice that HAA5 test results for first and second quarter of '04 <br />were still above limit (0.071 and 0.074 mg/L respectively) leaving the rolling average at <br />0.080 rog/L, requiring another public notice. In addition, the rolling average for TTHM <br />was also above limit, primarily because of the high level reported last September. <br /> <br />6/01/04 Submitted Plans & Specifications to VDH for approval for a Sodium <br />Permanganate feed system to be installed at the Reservoir Pump Station. <br /> <br /> <br />