IGP Case Studies on Treatment and Treatment Avoidance
« All Publications

According to the Storm Water Multiple Application Reporting and Tracking System (SMARTS), there are approximately 2,800 facilities covered by the Industrial General Permit (IGP) that have been elevated to Level 1 or Level 2, thus requiring additional control measures or technical demonstrations to comply with the IGP exceedance response action (ERA) process.

Many of these facilities are faced with compliance costs that could impact their ability to continue operating and are carefully evaluating the decision to pursue potential offramps, risk non-compliance or third-party lawsuits, or pay for potentially costly structural treatment. Through working with many clients facing these decisions, in addition to negotiating settlements with citizen suit plaintiffs, we have established an ERA compliance framework to avoid treatment where justified (e.g., non-industrial or natural background source demonstrations) or minimize long-term structural BMP costs where this last resort option is unavoidable.

This presentation will provide an overview of multi-region, multi-facility, and multi-constituent case studies outlining different compliance approaches based on site-specific conditions and priorities to offer lessons learned relevant to a wide audience facing their own unique compliance challenges. The step-wise framework will include:

  • Non-industrial source demonstrations to avoid treatment: Three case studies will be presented including an aerospace manufacturing facility, a refinery, and a lumber yard. We will cover the constituents of concern (magnesium, copper, and zinc), hypothesized sources, hypothesis-driven sampling design, sampling results, and outcomes, including removal of TMDL NEL-sampling parameters.
  • Optimization of existing treatment controls: Two landfill case studies will be presented where, through retention time optimization of existing basins and improved skimmer operation, iron and TSS NALs were met.
  • Sanitary Sewer Diversion: One waste transfer station case study will be discussed where limits were met for a wide range of pollutants (metals, COD, nutrients, and bacteria) through storage and discharge to sewer; the terms of the final permit, comparison of volume storage between the default IGP design storm and the onsite alternative compliance option, and bypass sampling results will be discussed.
  • Active treatment: Three case studies will be presented including two transfer stations and a landfill where active treatment was necessary to achieve the NALs, NELs, and Water Quality Standards. Treatment train unit processes included settling tanks, media filtration, ion exchange, chemical addition, and ultraviolet disinfection. We will discuss optimization modeling to reduce system cost and pilot testing to improve confidence in final treatment system performance.

This presentation will finish with a discussion of cost savings realized by each case study strategy. We believe this presentation will be relevant to a wide audience as the diverse set of case studies offers lessons learned and best practices covering a variety of pollutants and compliance strategies, providing an opportunity for the audience to glean relevant recommendations for their facilities with site-specific goals and constraints. This presentation ties directly into the 2020 theme of "envisioning the future" by outlining a sustainable pathway for industrial dischargers to meet IGP requirements and continue operating their businesses, thus providing local and regional economic benefits, in addition to the water quality benefits associated with permit compliance.

Publication Summary

  • Geosyntec Authors: Adam Questad, Brandon Steets
  • All Authors: Adam Questad, Brandon Steets
  • Title: California Stormwater Quality Association (CASQA) 2020 Virtual Conference
  • Event or Publication: Event
  • Practice Areas: Urban Stormwater Management Planning and Design, Water and Natural Resources
  • Citation: Several Geosyntec staff members will present at the California Stormwater Quality Association (CASQA) 2020 Virtual Conference on September 15 and 16, 2020.
  • Date: September 16, 2020
  • Location: Online
  • Publication Type: Platform Presentation