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Wastewater treatment involves several complex processes to transform incoming
wastewater into clean effluent discharged into waters of the state. The
processes include physical, mechanical, biological and chemical methods in a
specific sequence to separate solids from liquid, breakdown organic material and
disinfect the remaining water prior to discharge. Waste materials (Sludge) are
aerobically treated to produce a material that is periodically disposed by land
application. The processes are constantly operating, as wastewater continually
flows into, through and out of the treatment plant.
Wastewater Treatment Flow Diagram
EMD Wastewater Facility
The processes
below summarize those used at the EMD wastewater facility:
- Preliminary
Treatment involves the removal of sand or grit and paper materials. Sandy
material is removed by settling and paper materials are removed by cleanable
racks that trap paper as it floats by. Flow is also measured in this process.
- Primary
Treatment utilizes a settling tank (clarifier) to remove heavy organic material
and a skimmer to remove floating grease.
- Secondary
Treatment is comprised of two processes. In the first step, the organic material
(known as Activated Sludge) is mixed in the Aeration Tank using fine-bubble
diffusers, to provide oxygen for microorganisms that breakdown the material. In
the second step, a Final Clarifier is used to allow solids to separate from the
liquid slurry.
- Sand Filters
(Tertiary Treatment) are used to remove fine particles that do not settle out in
the final clarification process.
- Ultraviolet
(UV) radiation is utilized as a disinfectant method to kill essentially all
pathogenic bacteria. UV radiation kills disease-causing bacteria by
destroying genetic material and preventing cell replication.
- Aerobic
Sludge Digestion is a process used to break down waste organic material
generated from the treatment processes into an inert slurry which can be safely
disposed by a licensed contractor. Sludge (biosolids) is land applied per state
regulations as a beneficial use.
WJCMD Wastewater Facility
The West
Jefferson Metropolitan District Wastewater Treatment Facility utilizes the
following treatment processes:
- Preliminary
- Secondary
- Tertiary
The West Jefferson County Metropolitan District wastewater facility utilizes
identical technologies as the Evergreen facility, with the exception of the
Primary process. The disinfection process is accomplished with ultraviolet
light. Filtered effluent passes through a chamber that houses a bank of
ultraviolet lights. The energy from the lights kills the pathogenic bacteria.
The main advantage to this process is safety. Hazards inherent with ultraviolet
radiation do exist, but personnel do not handle more dangerous chlorinating or
dechlorinating chemicals and the possibility of those toxic chemicals being
discharged into the receiving water is removed. Kittredge Wastewater Facility
The Kittredge Wastewater
Treatment Facility utilizes the following treatment processes:
- Preliminary
- Secondary
- Tertiary
The Kittredge wastewater facility utilizes identical technologies as the
Evergreen facility with the exception of Primary Treatment. Sludge generated by
the treatment processes is aerobically treated, removed by and ultimately
disposed of by a licensed contractor. The Kittredge facility also utilizes a
polishing pond as a final filtering process prior to discharge into Bear Creek. |