HomeMy WebLinkAboutOWTS Certification LetterSeptember 17, 2007
502 Main Street • Suite A3 • Carbondale, CO 81623 • (970) 704-0311 • Fax (970) 704-0313
S OPRIS E NGINEERING • LLC civil consultants
Jeffrey Sabo
Legacy Homes of Aspen, Inc.
612 Surrey Road
Carbondale, CO 81623
RE: As-Built OWS System, Sabo Property, Lot A, County Road 109, Garfield, CO
SE Job No. 25254.01
Dear Jeffrey:
Pursuant to County Regulations, this letter provides documentation that the new OWS system recently
installed is in general compliance with the permitted design. Sopris Engineering has performed site visits
to measure, inspect, and document the as built conditions of the constructed system. The system was
inspected prior to backfilling and after all installations were completed. The as-built conditions and
installation of the new OWS components is in compliance with the permitted design specifications for the
system.
The septic tanks, transport distribution pipe, and absorption field installations are in accordance with
Garfield County Regulations, the design presented in the Sopris Engineering design drawing, dated April
14, 2006 and revised March 22 2007. A primary 1500-gallon dual compartment concrete septic tank and a
secondary 1000-gallon dual compartment concrete septic dosing tank was installed in series with an
Orenco duplex biotube filter pump assembly. The duplex dosing pump system is installed in the secondary
compartment of the second tank to dose primary treated effluent to the absorption field.
The full pressure dosed absorption field was constructed with a total of 72 Quick-4 Infiltrator leaching
chambers in a trench configuration with (6) 52-long trenches containing 12 chambers each. The
treatment/absorption field system is configured for alternating pressure distribution over 2 pressure
distribution zones (3 trenches per zone) through alternating pumps. The effluent from the secondary tank
is distributed by alternating duplex pump assemblies in the dosing/septic tank (pump vault). Each trench
has a custom perforated pressure distribution pipe running the length of the chamber row. Three trenches
are dosed per each dosing pump cycle by alternating pumps.
The dual 1.25-inch transport lines from each pump is bedded in road base and installed to allow gravity
drainage of effluent back to the tank and to the individual distribution zone manifolds respectively on each
set of trenches located at a high point at the head of the trenches. All distribution piping, valves and pump
assembly components have been installed and are in operation in accordance with the design and
performance specifications.
The chambers were backfilled with native soil and/or screened rock to the top of the chambers, and
backfilled to the finished surface grade with native soil. Each trench was installed level. Inspection ports
were installed on each end chamber. The chambers were installed in the native silty sand and gravel with
cobbles soils over 6” of concrete sand consistent across the field. The field has two sets of trenches with
pressure manifolds and individual split flow tees that connect with the pressurized perforated distribution
laterals at the head of each trench. The minimum setback distances have been maintained. The 6
Jeffrey Sabo
SE Job No. 25254.01
September 17, 2007
Page 2
trenches have a separation distance of approximately 6 feet and are installed approximately 2 to 3.5 feet
deep relative to the existing grades. Additional observations of the soils within the field were performed
during construction indicating that the soils are consistent with the reported descriptions. A minimum 6
inches of sand was placed in the trenches to mitigate the presence of cobbles and enhance treatment of the
effluent. No ground water was encountered in any of the excavations on site.
OWS Operation and Maintenance
The system shall be inspected on a regular basis and be properly maintained. The system and
responsibility for repair and maintenance of the systems will remain with the Owner. The owner shall
employ the services of qualified service providers to inspect the OWS and perform any maintenance
required and periodically pump the septic tank as necessary to ensure that the system is in good operating
condition and performing as designed. The OWS should require minimal maintenance. Several factors
influencing the system’s health, longevity and need for maintenance include: actual wastewater flows
versus design flows, the volume of kitchen/domestic waste (excluding human waste and toilet paper),
excessive use of household chemicals, extra strength laundry detergents and other toxic liquids. The tank,
sanitary tees and effluent filter should be visually inspected bi-annually for clogging debris, damage or
leaks. In general, for a properly utilized system, septic tanks should be pumped and inspected every 2 - 4
years. The effluent filter should be cleaned every six months and at the time of pumping. Absorption
fields should be maintained with suitable vegetative cover and kept free of root invasive plants. Positive
surface drainage away from the absorption field should be maintained.
If you have any question or need any additional information, please call.
Sincerely,
SOPRIS ENGINEERING, LLC
Paul E. Rutledge
Design Engineer
Yancy Nichol, P.E.
Principal