HomeMy WebLinkAboutCorrespondence APPLICANT 4/29/2008
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380 Q Street, Suite 200
Springfield, Oregon 97477
(541) 302-9790
(541) 485-3253 Fax
scott@olsonandmorris.com
Olson & Morris
A subsidiary of L.B. Olson & Associate, inc.
Consulting Engineers & Surveyors
Urban Planners .
Memorandum
To:
Eric Walter, Civil Engineer
Date Received:__~j/lJ ~,
Planner: SH
From: Scott Morris
Date: 4/23/2008
Re: Aramark Sanitary. Outflow Analysis
Eric,
I have reviewed the Aramark plan to determine the average and peak outflow from the site to the
sanitary system in 40th Street. The plan is to have a Jensen 800 OP washer, that uses 653 gallons per
load. The loads take 30 minutes, so twice per hour there will be 653 gallons dumped into the surge
tank. The surge tank is made up of (2) chambers that are 1500 gallons each, which then is pumped at
a rate of 27 gallons per minute (gpm) to the shaker screen, then to the public system.
So, the analysis was to determine if, the tanks were adequate size to accommodate these needs.
Below is a spreadsheet showing the inflow and outflow from the tank at 30 minute increments. As you
can see, at 27 gpm outflow, the tank drains prior to the next load, therefore there is not a problem.
The other flow from the site is from the sinks, bathrooms, etc. from the building. It is hard to tell what
the average flow would be. However, we estimate the peak flow will be a maximum of 4 gpm, which
will be in addition to the 27 gpm from the washer.
653 gallons / 30 minutes 27 gpm
Minutes Inflow Outflow Remainder
30 653 -810 -157
60 653 -810 -314
90 653 -810 -471
120 653 -810 -628
150 653 -810 -785
180 653 -810 -942
210 653 -810 -1099
240 653 -810 -1256
270 653 -810 -1413
300 653 . -810 -1570
330 653 -810 c1727
360 653 -810 -1884
390 653 -810 -2041
420 653 -810 -2198
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Conclusion
;.
450
480
653
653
-2355
-2512
-810
-810
The average flow from the development to the public system should be in the neighborhood of 28 gpm,
with the peak flow topping out at 31 gpm. If you have any questions about this analysis, don't hesitate
to call.
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