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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: | 08/31/2015 | ||
| 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: Follow up to turbidity spike 8/29/15 DETAILS: Phil called at 9:30 am to inform me that filtered turbidity spiked up to 1.78 NTU for a brief (30-60 min.) period between 6:30 am and 8 am on 8/29, due to high (6.5 NTU) Graham Creek water and high demand (PASS-CX feed and filter could not keep up with amount of turbid water sent through plant). Phil responded to the high NTU alarm and by 730 am on 8/29 was manually setting the streaming current detector to feed more PASS-CX and backwashed the filter. By 8 am, filtered NTU down to around 0.16. Given that approximately 5700 gal of high turbid water (95 gpm plant flow for 60 min.) would have likely been flushed due to 80-90,000 gal/day usage over past 2 days, 4-hour reads < 1.49 NTU, and chlorine residuals high enough to meet CTs easily, I decided not to require a boil water notice now. I reminded Phil to contact DWS right away in future for any NTU spike. Phil has DWS after hours #. ACTION NEEDED: Midland to collect September coliform sample(s) this Wed and note on August monthly report if filtered turbidity triggers exceeded (yes/no). Midland to continue to address high NTU spikes by fixing leaks in distribution system to slow plant down and allow flexibility to wait out high storms by using storage in future. Creek intake and raw sedimentation will be getting cleaned out. System will continue to try to address streaming meters ability to handle power outages and raw NTU spikes to feed appropriate chemical for flocculation. 10/22/15 update: IFE trigger exceeded for August (2 consecutive 15 min. readings > 1.0 NTU). System has met requirements by stating reason for exceedence on SWTR form. I requested a filter turbidity backwash profile from operator. 11/16/15: System produced filter NTU profile from 11/15/15. Only optimization goal not met was system returned to service at > 0.10 NTU (0.13 NTU). | ||