Gerald,
I just got off the phone with River City Environmental. They are still preparing their final reports. However, preliminary results (map and measurements) are attached.
Bottom line: although our Plant Operations staff insist there are no significant biosolids in Lagoon 1 and we should not remove biosolids next year, we appear to be measuring an AVERAGE sludge depth of 7.0’, with the least %solids measured being 7%, and the max 14%.
Given this, it appears lagoon 1 is extremely full, water cap appears minimal, and the temperatures must be close to ambient air temp or above simply due to lack of water depth – prime habitat for algae. This confirms what we were suspecting back in in December when the water was drawn down to 7.5’: we were not looking at water, or a floating algae cap. We were looking directly at sludge. We should definitely sludge judge lagoon 2!
It is my opinion that you are on the right track scheduling an extensive review of the daily operations of the plant by Dyer Partnership. I intend to make it my highest priority in the coming months, as the City (all of us) should think deeply about how we are planning and operating the plant. I’ll begin preparing and RFP for biosolids removal, with the intention of launching a contractor to remove most of this material before September 2018, pending further information from credible folks involved. The full cooperation of the Plant Operators will be a critical factor.
Thank you,
Andy Peters
City of Molalla
Public Works Operations Supervisor
(503) 829-6855 x220
Cell: 503-793-0507
117 N Molalla Ave
Molalla, OR 97038
From: Patrick Dunigan [mailto:patrick.dunigan@rivercityusa.com]
Sent: Wednesday, February 21, 2018 1:58 PM
To: Andy Peters <apeters@cityofmolalla.com>
Subject: FW: WWTP Jar Test
Andy,
This just some of the rough info right now . for Lagoon 1
From: Dane Marcelletti [mailto:Dane@ced.biz]
Sent: Tuesday, February 20, 2018 10:39 AM
To: Patrick Dunigan
Cc: Mark Marcelletti
Subject: WWTP Jar Test
Hey Patrick,
Attached is the spread sheet for the 4 lagoons at the WWTP. I have jury duty today so I will get to the Water Plant samples tomorrow.
Let me know if you have any questions.
Thanks,
Dane
Dane Marcelletti
(805) 660-8345