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Even though we are well into the second year of the “New Permit” (Order 2014-0057-DWQ) in California, there seems to still be a lot of confusion about what major changes were made from the “Old Permit” (Order No. 97-03-DWQ). We would like to set the record straight and give some clarity on the battle of Old vs. New. It may seem harsh to say that you still don’t know, but in at least a quarter of our training sessions on the California Industrial Stormwater Permit (IGP), key members of the stormwater pollution prevention team are operating under an outdated understanding of the permit requirements. So what are the differences from Old to New stormwater permit that we see most facilities and consultants struggle with? I’m glad you asked, below is a table explaining the must-knows for industrial stormwater permit success.
Old Permit                                               vs.                                                New Permit
Discharger must collect the first storm event of the “wet season” Dischargers are not required to sample the first Qualifying Storm Event (QSE)
Dischargers must sample 2 times a year Dischargers must sample 4 times a year, twice from July 1st – December 31st and twice from January 1st – June 30th.
Sample collection must be proceeded by 3 days of no discharge from the facility Sample collection must be proceeded by 48 hours (2 days) with no discharge
Sample collection must be within the first hour of discharge Sample collection must be within the first 4 hours of: a. discharge from each discharge location during facility hours b. the time the facility opens, if discharge began within the previous 12 hours period
 Basic sampling parameters requirements:
  • TSS
  • pH (OK to be analyzed by the lab)
  • TOC or Oil and Grease (choose one)
  • Specific Conductance
Additional parameters:
  • Determined by SIC code
Basic sampling parameters requirements:
    • TSS
    • pH (conducted in field within 15 mins)
    • Oil and Grease
(No more TOC or Specific Conductance) Additional Parameters:
  • Determined by SIC code
  Hope this little snippet gives a clear picture of the New Industrial Stormwater Permit (IGP) requirements. Still have some burning questions? Give us a call, we have the answers.

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