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MEMORANDUM
To: Mr. Roger Peitso, Building Official City of Orono, MN
From: Paul Brandt PSS Soil Investigation & Design, Inc.
Date: October 8, 2018
Subject: 2300 Fox Street, Orono, MN
We have reviewed the information you provided today. We understand that this is a
unique location with significant limitations. We reviewed the revised design under the
following assumptions:
1. The area must be of adequate size to absorb the design flow from the site’s residence
which is 750 gallons per day.
2. The average contour loading rate must not exceed 12 gallons per day.
3. The dispersal area must meet code requirements for orifice size and spacing.
4. The dispersal lines must be installed to allow the operator to service the lines and adjust
the flow to each line.
We have reviewed the submitted revisions; we have found that:
1. The area of the dispersal bed is 1,268 square feet which exceeds the minimum bed size of 1,250
square feet. The bed size is adequate.
2. The average contour loading rate must not exceed 12 gallons per day. The average
contour loading rate calculates to less than 12 gallons per day. The contour loading rate
is adequate.
3. The dispersal area must meet code requirements for orifice size and spacing. According
to the Septic Resources work sheet if the orifice is 7/32 inch with spacing of 3 feet then
the distribution is adequate. (Note: other combinations may work but they must be
specified.)
4. The dispersal lines must be installed to allow the operator to service the lines and adjust
the flow to each line. It is unclear if the distribution is center feed or end feed. The
distribution appears to be center feed which is acceptable. Due to the layout (uneven
lateral length) end feed will not meet code. Further, also unclear the (but because of the
unequal number of lateral) a squirt test must be completed. Therefore, each lateral must
have valves installed to regulate the flow and pressure in each lateral.
With these provisions this design is approvable by the City of Orono and the permit can
therefore be issued by the City of Orono. Thank you for your time.
I hereby certify that I am an advanced designer and am qualified to design/review this
work in accordance with all applicable ordinances, rules and laws.
Paul Brandt, Lic. # 5182; Soil Investigation & Design, Inc. Lic. #3263