2018-11-05_PERMIT FILE - C1981044 ‎(12)‎

• Permit No: C1981044
• IBM Index Class Name: Permit File
• Doc Date: 11/5/2018
• Section_Exhibit Name: EXHIBIT 02 OTHER REQUIRED PERMITS
• Media Type: D
• Archive: No

• COLORADO DEPARTMENT OF HEALTH
Water Quality Control Division
Rationale - Page 3
Permit No. CO -0034142
Outfall 023
This outfall is the discharge point from the domestic wastewater treatment
facility (WWTF). Sources of wastewater are the bath houses, the maintenance
shop, the laboratory and several offices. Washdown from the maintenance
shop's bay and service areas is the major contributor.
The estimated daily influent flow is 0.0088 MGD, 0.0027 MGD of which is
derived from industrial sources such as washdowns.
Collection and conveyance of the generated wastewater is by 6 and 8 inch PVC
pipe. One lift station, located approximately 200 feet west of the treatment
facility, is employed within the system.
Pumping -is accomplished with duplex grinder type submersible sewage pumps
having a peak capacity of 90 gallons per minute.
A gravity oil and grit separator is used for pretreatment of the wastewater
• generated from the washdowa bay and service areas of the maintenance shop
building. No other pretreatment processes are presently used.
The wastewater treatment facility is a three cell plastic lined aerated
lagoon. Figure 2 in the permit gives the relative sizes of each lagoon cell.
All of cell A and the first two-thirds of cell B are aerated. Cell C is used
as a polishing pond. Capacity for the lagoon is approximately 334,000 gallons
for cell A, 262,000 gallons for cell B and 91,000 gallons for cell C for a
total capacity of 687,000 gallons. The detention time for this lagoon system
is 57 days at the design flow of 0.012 MGD. Organic loading capacity is 25
lb/day of BOD.
Chlorination is performed following cell B before the flow enters the
polishing pond. A solid tablet type chlorinator is housed and located on the
dividing wall between cells B and C.
Approximately once every 5 to 10 years, the lagoon system will require
dredging of accumulated sludge. This will be handled by a licensed contractor
and the material will be disposed of in an approved landfill. The oily waste
and grit separator will require more frequent cleaning. The material from
this structure will also be removed and disposed of by a licensed contractor.
Effluent from this facility is measured with a 1200 V -notch weir located at
the polishing pond outfall. The discharge is conveyed to discharge point 023
at the Williams Fork River via a 6 inch outfall pipe. Samples are to be
collected from the polishing pond effluent at the weir location.
. After discussion and review of this facility's plans and specifications, it
was determined that the facility is designed in accordance with the
Department's Design Criteria for Wastewater Treatment Works.