OHA Drinking Water Services
Contact Report Details |
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PWS ID: | OR41 01139 | ||
PWS Name: | MIDLAND WATER ASSOCIATION | ||
Who Was Contacted and Phone: | Phil White (360) 560-0248 | ||
Contact Date: | 01/16/2015 | ||
Contacted By: | NUSRALA, JAMES (REGION 1) | ||
Contact Method/Location: | Office | ||
Assistance Type: | OTHER REGULATORY - REGULATORY ASSISTANCE | ||
Reasons: | SWTR Operations |
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Details: | SUMMARY: Disinfection interruption DETAILS: During a site visit on 1/14, it was determined that the chlorine feed pump was not injecting any chlorine in the feed line, due to a feed pump malfuction. Operator was unsure how long feed pump was not working. Feed pump repaired on 1/14 with solution being injected. Phil indicated that first user residuals had not dropped below the 0.6 mg/L alarm during this time, and that at least 8 feet of water was kept in the reservoir to ensure adequate contact time. During the visit the CL-17 chlorine analyzer began to malfuction. Grab samples taken by both Phil and DWS on portable instruments indicated at least a 1.0 mg/L first user residual. Phil collected grab samples at least twice a day on 1/14, 1/15, and 1/16, to document at least a 0.8 mg/L chlorine residual. It was decided that since adequate disinfection was occuring, that there was not a slug of undisinfected water that could be sent to the users, and the storage tank volume did not need to be drained. ACTION NEEDED: Phil to use the lowest value of grab samples of the day for CT calculations. Phil to order new photo cell for chlorine analyzer. |