HomeMy WebLinkAboutEngineer's ReportPO Box 2844
SJ e p t I G Glenwood Springs, CO 81602
S [IIY f WIC Fax 303-216-2796
May 17, 2012
Bridger Smith
381 Isabel Hay Road
Aspen, CO 81611
Onsite Wastewater Treatment System Design
3 -Bedroom Main Residence + Y2 bath in Agricultural Storage Building
4110 County Road 243
Garfield County, Colorado
Bridger,
Project No. C1001
ALL SERVICE septic, LLC has designed an onsite wastewater treatment system (OWTS) for the
subject residence. The property is located outside of New Castle, in an area where OWTSs and wells
are necessary.
SITE CONDITIONS
A 3 -bedroom, single-family residence and detached agricultural storage building with %2 bath (toilet
and sink) is proposed. The proposed barn will not have plumbing needing an OWTS. Floor drains in
should be routed to a drywell separate from the OWTS. All existing buildings will be razed the
existing OWTS will be abandoned.
SUBSURFACE
The subsurface investigation was performed by HP Geotech, Job # 112 088A, dated April 30, 2102. One
profile boring and three percolation pits were dug, as indicated on Figure 1 of the HP Geotech report.
Subsurface soils consist of loam to extremely gravelly sand. Percolation rates were variable with an
overall average percolation rate of 30 minutes per inch (MPI).
DESIGN SPECIFICATIONS
The OWTS design is based on 3 -bedrooms and a detached agricultural storage building with E/2 bath
(toilet and sink). An average daily wastewater flow of 490 GPD will be used. The installation must
include a 1000 -gallon, two-compartment septic tank at the main residence. An additional 1000 -
gallon, two-compartment septic tank is recommended near the agricultural storage building. Effluent
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will gravity flow to a minimum 4 -outlet, baffled distribution box which must be accessible from
grade. Effluent will be evenly distributed to four shallow beds, with each bed consisting of 2 rows of
8 Quick 4 chambers, for a total of 64 Quick 4 chambers. Prior to construction, the field area must
be staked out to confirm proper setback distances from the well and Main Elk Creek to the
absorption area.
Construction must be according to Garfield County Sewage Disposal Regulations, the Individual
Sewage Disposal (ISDS) Permit provided by Garfield County Building Department, and this design.
OPERATION INFORMATION AND MAINTENANCE
The surface of the absorption area should be seeded upon completion. Vegetation is an important
factor in absorption area performance. Erosion control should be practiced prior to and during re -
vegetation. Geo -fabrics or plastics should not be used over the absorption area. No heavy equipment,
machinery, or materials should be placed on backfilled absorption area. Livestock should not graze
on the absorption area. Plumbing fixtures should be checked to ensure that no additional water is
being discharged to OWTS. For example, a running toilet or leaky faucet can discharge hundreds of
gallons of water a day and harm an absorption area.
The homeowner should pump the septic tank every two years and clean the effluent filter as needed.
Garbage disposal use should be minimized, and non -biodegradable materials should not be placed
into the OWTS. Grease should not be placed in household drains. Loading from a water softener
should not be discharged into the OWTS. No hazardous wastes should be directed into the OWTS.
Mechanical room drains should not discharge into the OWTS. The OWTS is engineered for
domestic waste only.
ADDITIONAL CONSTRUCTION NOTES
If design includes a pump, air release valves and weep holes should be installed to allow pump lines
to drain to minimize risk of freezing. Excavation equipment must not drive on absorption area due to
the potential to compact soils. Extensions should be placed on all OWTS components to allow access
to them from existing grade. Precast concrete tanks and distribution boxes should be used, unless
plastic or fiberglass is required. Access to all tank compartments and distribution devices is optimal.
INSTALLATION OBSERVATIONS
ALL SERVICE septic, LLC must view the OWTS during construction. The OWTS observation
should be performed before backfill, after placement of chambers and distribution pipes. Septic tanks,
distribution devices, pumps, dosing siphons, and other plumbing, as applicable, must also be
observed. ALL SERVICE septic, LLC should be notified 48 hours in advance to observe the
installation.
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LIMITS:
The design is based on information submitted. If soil conditions encountered are different from
conditions described in report, ALL SERVICE septic, LLC should be notified. All OWTS
construction must be according to the county regulations. Requirements not specified in this report
must follow county regulations. The installer should have documented and demonstrated knowledge
of the requirements and regulations of the county in which they are working.
Please call with questions.
Sincerely,
ALL SERVICE septic, LLC
Ow, Ca, Dv-6cAg
Carla Ostberg, MPH, REHS
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