OHA Drinking Water Services
OHA Drinking Water Services
Contact Report Details

PWS ID: OR41 90416
PWS Name: GEORGIA-PACIFIC, WAUNA MILL
 
Who Was Contacted and Phone: Jeffery Sorensen (503) 455-3236
Contact Date: 04/26/2013
Contacted By: HOFELD, EVAN (REGION 1)
Contact Method/Location: Office
 
Assistance Type: WATER QUALITY ALERT RESPONSE
Reasons: SWTR
Operations
 
Details: SUMMARY: Operations DETAILS: I received a call from Jeff Sorensen regarding a brief spike in filter effluent turbidity. The spike ocurred at 11:33 AM on 4/26/13 and the turbidity was above 1.49 NTU for about 90 seconds, with a maximum spike of 1.56 NTU. There was no corresponding spike in the influent turbidity prior to the pressure filters, which comes from a sidestream of water that has been fully treated through a rapid rate plant, primarily for use as process water. Turbidity was back down to 0.09 NTU and the 4-hr compliance readings were all within normal ranges. They are still investigating the cause of the incident. Even at a 200 gpm max flow, 90 seconds above 1.49 NTU, would only amount to 300 gallons into a 50,000 gallon clearwell (25,000 gallon at lowest level), which would be about 0.6 - 1.2% of the available storage. Contact time is 132 min at 200 gpm and 42,092 tank volume and 0.63% baffling factor (from tracer study). ACTION NEEDED: Further investigate cause and extent of the treatment implications.
 
Associated Alerts: N/A - -