Field Office Compliance - Assistance

Assistance ID - 105975
Des Moines Water Works - 310338211
9966 Maffitt Lake Dr Cumming, IA 50061
Dallas County

FO 5

Report
File Name File Type File Date Note
Comments
3/22/2019 Experienced a low LRV of 1.7 Sunday March 10, 2019, that shut UF#1 down. Kept it off till maintenance could look at and when they air it up they didn't see anything to "fix." Eventually they discovered problems with two valves. One was a large 16 inch valve that had to be replaced. It is responsible for pressurizing the unit to do the DIT. The other was smaller air inlet valve that was stuck partially open; it was repaired. Everything was started back up on the 13th and LRV was 5.9; the next day the LRV from the DIT was back to 4.2. Kyle had questions about reporting this on the MOR, so we discussed it. Turbidity was all good before, during, and after the shutdown and the LRV the day before, 3/9, was 4.3. Regulation says if the direct integrity test exceeds the control limit, the system must remove the membrane unit from service, which DMWW did. A DIT must be done to verify any repairs. A DIT is performed daily. 43.11(12) JANET GASTINEAU
State of Iowa DNR Home Site Policy
Leading Iowans in caring for our natural resources
Version: 2.3.1.23706
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