HomeMy WebLinkAboutApp F System Narrative NTI ENGINEERING & LAND SURVEYING
717 South Peabody Street, Port Angeles, WA 98362
360-452-8491 info@nti4u.com
April 22, 2016
Isaac Wedam
Blair, Church & Flynn Consulting Engineers
451 Clovis Avenue, Suite 200
Clovis, CA 93612
Subject: Kalaloch Cabins Septic System
Dear Isaac,
This letter is meant to summarize the proposed septic system at the cabins in Kalaloch.
There are 24 new cabins proposed, each of which will contribute 130 gallons per day (GPD) of
sewage. This results in a total of 3,120 GPD of sewage, which is below the threshold of 3,500
GPD to consider this system a Large On-Site System which would require permitting through
the Washington State Department of Health. The Jefferson County Environmental Health
department will have jurisdiction over permitting of this system.
NTI has gone to the site and investigated th e soils. The most suitable system to put in
place on the site would be a subsurface drip system. This is due to the high water table in the
area which would restrict a conventional system from being used. The area of the drainfield is
proposed to be placed had soils type 5 and type 6 soils to a depth of approximately 6’ deep. At
6’ deep there was a type 1 gravelly sand layer. We are proposing to remove the soil in the
drainfield area to a depth of approximately 6’ to reach the permeable sand layer. C-33 sand
would then fill the area to grade replacing the less permeable soil. This will reduce the footprint
needed for the drainfield area by almost 5 times what would be necessary if the type 6 soil was
left in place. This type of drainfield is similar to the existing drainfield on site.
Collection of sewage from the cabins will be done with gravity sewer lines which will
flow to septic tanks throughout the development. The septic tanks will connect to pump
chambers which will pump the sewage to the main setic tanks near the drainfield. The gravity
and pressure lines will occupy the same trench approximately running beneath the walking
path proposed between the cabins. This should reduce the need for clearing and disturbing
existing vegetation as much as possible as well as meeting minimum setback from the water
well. We feel this system design will have the least impact as opposed to other design
concepts.
If you have any questions please let us know.
_________________________
Zach Slota
Project Manager
NTI Engineering and Surveying