|HSD’s Compliance with EPA’s Nine Minimum
Controls Nine Minimum Controls HSD Compliance
Proper operation and regular maintenance programs for the sewer system and
operation is managed by HSD staff using SCADA and data collection programs.
HSD maintains CSO outfalls and pump stations continuously, using state of the
art Reliability-Centered Maintenance (RCM) procedures. Sewer Maintenance
Dept. staff inspects sewers on a specified schedule and perform corrective
actions when deficiencies are found.
|2. Maximize use of collection system for storage.
emphasizes storage projects for CSO control. SCADA monitors outlying stations
to maximize flows to the WWTP, and to store excess flows to the maximum
|3. Review and modification of pretreatment requirements to
ensure that CSO impacts are minimized.
Pretreatment Program issues permits that set limits on the chemical contents
of industrial discharges. The program includes monitoring and permit
enforcement, education, and technical assistance to businesses on appropriate
waste pretreatment and disposal techniques.
|4. Maximization of flow to wastewater treatment plant for
is used to monitor flow to the HSD main treatment plant. Analyses for CSO
control project alternatives include storage, and transfer to the wastewater
|5. Elimination of CSO’s during dry weather.
and maintenance programs, as described for the first control, focus on
preventing dry-weather overflows. The conveyance system is monitored through
SCADA and direct observation; corrective action is taken immediately if a
problem occurs. Equipment problems are immediately reviewed, with problem
resolution aggressively pursued.
|6. Control of solid and floatable materials in CSO’s.
of solids and floatable material is accomplished using screen rakes at
outlying station intakes. HSD’s screen rake maintenance program limits the
introduction of solids and floatable materials to sewers. Also, the majority
of floatables in the HSD system are captured in the large volume of
wastewater transferred to the treatment plant before overflows occur. Unusual
observations of the quantity of solids and floatables are acknowledged,
investigated, and resolved.
|7. Pollution prevention programs to reduce contaminants in
Pretreatment Program and has a major presence with local industries. Of the
many program goals, reducing discharge to sewers that adversely impact the
environment and the wastewater treatment processes is given priority.
Educational materials on controlling trash disposal to sewers are a part of
the larger public information program.
|8. Public notification program to ensure that public receives
adequate notice of CSO events and impacts.
operates a CSO Notification Program. This program includes the posting of
signs at publicly accessible CSO locations, automated email notifications, a
Web site, a brochure, and other public outreach activities.
|9. Monitoring to effectively characterize CSO impacts and the
efficiency of CSO controls.
monitors and records all CSO discharge volumes, precipitation data, and
submits monthly reports to the Indiana Dept. of Environmental Management.