From: Jennifer Cline
Sent: Fri Nov 06 12:03:53 2015
To: Gerald Fisher
Subject: RE: Leak Test Info
Importance: Normal
Hi Gerald, Sounds good, and they WILL nit-pic for sure.
We also know that DAF #1 (which is an inflow from Lagoon 2). Based on Jason’s thoughts, he figures the leak was approximately 500 gallon/minute. This was more than I had originally assumed. The flow then cycled back to the Aeration basin and eventually into Lagoon #1.
I think it’s safe to say we will need to repeat the test once repairs are made.
Jennifer Cline, P.E. | Public Works Director
Licensed in OR, WA
117 N Molalla Ave. | PO Box 248 * |Molalla, OR 97038
O: 503.759.0218 | F: 503.829.3676
From: Gerald Fisher [mailto:geraldf@pdgnw.com]
Sent: Friday, November 06, 2015 11:34 AM
To: Jennifer Cline <jcline@cityofmolalla.com>
Subject: RE: Leak Test Info
Hi Jennifer,
Based on the limits of the test requirements included in the report, leakage over ¼” may be a concern to them which is why they are asking for a wastewater engineer’s review.
From the report, “In priority areas, any rate of seepage greater than zero may warrant direct sampling and monitoring of the groundwater. Seepage of 1/8" per day or less is normal. However, this low rate can cause groundwater contamination where lagoon contents are strong and background levels are high quality. Seepage exceeding 1/4" per day indicates a seal failure, or absence of adequate initial seal.”
When I look at the combined data, assuming the lagoons are connected due to a bad valve, The maximum seepage is 2.7 inches per day, minimum is essentially zero, and the average is 1.4 inches per day. The max and average are well above the ¼” and due to some other connections you can actually have a positive value and elevation increase in the ponds. The other hang up they likely have is the measurements of the pond are in 0.1 feet increments and they are looking for 1/8” and 1//16” increments. Not sure you can do that without setting up a very accurate gauge close to the edge of each pond.
In short, the way the test is set up they can nit-pick it to death if they want. I will ask Tasha in our office if she has any lagoon experience. She graduated in environmental engineering and used to work for the City of Salem in their wastewater treatment department. I’ll get back to you.
Regards,
Gerald Fisher, PE | Senior Project Manager
PROJECT DELIVERY GROUP, LLC | 3150 22nd Street SE; Salem, OR 97302
www.PDGNW.com | 503-364-4004 (O) | 503-679-9237 (C)
** 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: Jennifer Cline [mailto:jcline@cityofmolalla.com]
Sent: Friday, November 06, 2015 9:32 AM
To: Gerald Fisher <geraldf@pdgnw.com>
Subject: RE: Leak Test Info
No, not at this time.
Jennifer Cline, P.E. | Public Works Director
Licensed in OR, WA
117 N Molalla Ave. | PO Box 248 * |Molalla, OR 97038
O: 503.759.0218 | F: 503.829.3676
From: Gerald Fisher [mailto:geraldf@pdgnw.com]
Sent: Friday, November 06, 2015 9:29 AM
To: Jennifer Cline <jcline@cityofmolalla.com>
Subject: RE: Leak Test Info
Reading the report. Quick question, do you have monitoring wells outside of the lagoon?
Regards,
Gerald Fisher, PE | Senior Project Manager
PROJECT DELIVERY GROUP, LLC | 3150 22nd Street SE; Salem, OR 97302
www.PDGNW.com | 503-364-4004 (O) | 503-679-9237 (C)
** 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: Jennifer Cline [mailto:jcline@cityofmolalla.com]
Sent: Wednesday, November 04, 2015 5:11 PM
To: Gerald Fisher <geraldf@pdgnw.com>
Subject: Leak Test Info
Jennifer Cline, P.E. | Public Works Director
Licensed in OR, WA
117 N Molalla Ave. | PO Box 248 * |Molalla, OR 97038
O: 503.759.0218 | F: 503.829.3676