HomeMy WebLinkAboutEngineer's Report.pdfPO Box 2844
tIC Glenwood Springs, (0 81602
Ph 970.618.5033
Fax 303.216.2796
April 20, 2011 Project No. 1834
Owen Minney
1416 County Road 132
Glenwood Springs, CO 81601
Subsurface Investigation and Onsite Wastewater System Design, 2 -Bedroom Structure
1416 County Road 132
Garfield County, Colorado
Owen,
ALL SERVICE septic, LLC performed a subsurface investigation and an onsite wastewater system
(OWS) design for the subject residence. The property is located outside of Glenwood Springs, next to
the Fish Hatchery, in an area where OWS are necessary.
SITE CONDITIONS
A 2 -bedroom residence exists, which utilizes an OWS which is experiencing problem and must be
replaced. There is a garage and shed on the subject property. The proposed drain field area lays
downslope of the residence in a grassy area. Water is provided to the residence via a spring located
100+ feet away from the proposed drain field.
SUBSURFACE
The subsurface was investigated by digging one profile pit, as indicated. The materials encountered in
the profile pit consisted of a thin layer of topsoil, underlain by sandy clay to 7 feet, the maximum depth
explored. Groundwater was encountered at 6.5 feet. An LTAR of 0.95 will be used to design the
OWS.
DESIGN SPECIFICATIONS
The OWS design is based on 2 -bedrooms and an average sewage load of 300 GPD. The installation
must include a 1000 -gallon, two-compartment, precast concrete septic tank, with an effluent filter on
the outlet, followed by three gravelless chamber trenches. Each trench must have 8 Low Profile
`Quick -4' chambers or 7 Low Profile 'Arc 36' chambers, for a minimum total area of 237 SF. Six
inches of sand must be placed beneath each row of chambers. A distribution box must be used to
distribute effluent.
Onsite Wastewater System
Project No 1834
April 20, 2011
Page 2
Construction must be according to the county ISDS regulations, the septic permit provided by Pitkin
County Environmental Health Department, and this design. This design for the subject property, noted
above, is valid only in conjunction with the approved County Health Department permit.
OPERATION INFORMATION AND MAINTENANCE
The surface of the drain field should be seeded upon completion. Vegetation is an important factor in
drain field performance. Erosion control should be practiced prior to and during re -vegetation. Geo -
fabrics or plastics should not be used over the drain field. No heavy equipment, machinery, or
materials should be placed on backfilled drain field. Livestock should not graze on the drain field.
Plumbing fixtures should be checked to ensure that no additional water is being discharged to OWS.
For Example, a running toilet or leaky faucet can discharge hundreds of gallons of water a day and
harm a drain field.
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 OWS. Grease should not be placed in household drains. Loading from a water softener
should not be discharged into the OWS. No hazardous wastes should be directed into the OWS.
Mechanical room drains should not discharge into the OWS. The OWS 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 in excavation of drain
field due to the potential to compact soil. Extensions should be placed on all septic tank 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, and the county must view the OWS during construction. The OWS
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.
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 OWS 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
Timothy R. Petz
3 copies
Reviewed By:
Onsite Wastewater System
Project No 1834
April 20, 2011
Page 3