51
Standard Operating Procedure for:
A.6
IDDE: Tracing Illicit Discharges
Purpose of SOP: | To provide a quick reference list of items to keep in mind during tracing activities to
efficiently and systematically identify the source of an illicit discharge.
Always:
é
Review / consider information collected when illicit discharge was initially identified (Incident
Tracking Sheet or Dry Weather Outfall Inspection Form).
@ Survey the general area / surrounding properties to identify potential sources of the illicit
discharge as a first step.
@ Trace illicit discharges using visual inspections of upstream points as a second step.
@ Document tracing results for future reference.
Whenever Possible:
@ Use weirs, sandbags, dams, or optical brightener monitoring traps to collect or pool
intermittent discharges during dry weather.
@ Smoke test or televise the storm drain system to trace high priority, difficult to detect illicit
discharges.
@ Dye test individual discharge points within suspected buildings.
@ Ifthe source cannot be found, add the location to a future inspection program.
@ Collect bacterial samples of flowing discharges to confirm/refute illicit discharge.
Never:
@ Never enter private property without permission.
@ Never put yourself in danger.
A-10
Hic it Discharge Detection and Himination Plan 51
