From: Gerald Fisher
Sent: Mon Jul 31 17:41:18 2017
To: Jason Clifford
Subject: RE: July turbidity
Importance: Normal
Thanks Jason. It keeps coming back to Class A is hurting us bad and will be hard to get out of it.
Regards,
Gerald Fisher, P.E. | Public Works Director
City of Molalla
117 N Molalla Ave. | PO Box 248 |Molalla, OR 97038
Office: 503.829.6855 | Direct: 503.759.0218
CONFIDENTIALITY NOTICE: The information contained in this email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient and have received this communication in error, please contact the sender by reply email and destroy all copies of the original message. Thank you.
From: Jason Clifford [mailto:jclifford@cityofmolalla.com]
Sent: Monday, July 31, 2017 5:30 PM
To: Gerald Fisher <gfisher@cityofmolalla.com>
Subject: RE: July turbidity
Hello Gerald,
The bad thing is, everything is working. They’re just really bad filters. When the temps go up in the lagoons, currently 80+ degree F (at the bottom of the lagoon), the ACH doesn’t react as well as winter temps. The DAF’s are running 7-8 TSS; well below design specs. The filters aren’t doing well. All flow is going through the filters. I shut down DAF #1 to see if that helped and it didn’t. There is media and the backwash pump is below the 2100 gpm max for the filters. Lagoon levels are at 9.5’ and we’re pulling from the middle of the lagoon depth. Lagoons are notorious for high solids content, which is why Class A is not going to work here. The CCB isn’t constructed like a traditional CCB, which would help with solids settling. The pool vacuum works for about 45 minutes and then the filter bag is plugged up with algae. If you look at past DMR’s, the turbidimeter was messed with. Those low numbers are inaccurate, even when I was here year 1. It was caught last year, repaired and now those are real numbers. We won’t see good NTU’s until mid September, maybe. You’re not gonna find a similar system as here running consistent Class A. In my research, I haven’t found a lagoon system required to produce that high a quality effluent.
Thanks,
Jason
From: Gerald Fisher [mailto:gfisher@cityofmolalla.com]
Sent: Monday, July 31, 2017 4:44 PM
To: Jason Clifford <jclifford@cityofmolalla.com>
Cc: Dan Huff (Molalla) <dhuff@cityofmolalla.com>
Subject: July turbidity
Hi Jason,
We went over turbidity limits on the 7th and 8th and have exceeded turbidity limits since the 13th according to the DMR sheet if I am reading this right. Can you let me know the detailed cause and how we can address this problem so I can inform the attorneys. I understood the turbidity was a function of the filters. Are they working correctly? Are we having problems with the filters. I need more info from you on this. Tomorrow is fine. Have a good evening. Thanks Jason.
Regards,
Gerald Fisher, P.E. | Public Works Director
City of Molalla
117 N Molalla Ave. | PO Box 248 |Molalla, OR 97038
Office: 503.829.6855 | Direct: 503.759.0218
CONFIDENTIALITY NOTICE: The information contained in this email message, including any attachments, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. Any unauthorized review, use, disclosure or distribution is prohibited. If you are not the intended recipient and have received this communication in error, please contact the sender by reply email and destroy all copies of the original message. Thank you.