Webinar: common industrial stormwater pitfalls—examples and practical fixes

At a City of Oklahoma City webinar, Nathan Collier of WSP illustrated common compliance failures and practical fixes with three case studies: a concrete recycling facility with metal discharges, a construction site bacterial incident from a tipped portable toilet, and planning for a new food facility in a PCB-impaired watershed.

In the metals example Collier described a permitted, long-established concrete recycler that detected elevated zinc, aluminum and iron because rebar was stored in damaged, open-top rolloffs that allowed stormwater contact. The facility's remedy included procuring new tarped rolloffs, sheltering materials prior to forecasted precipitation, scheduling more frequent vendor pickup, and installing a metals filter sock around the outfall; the SWIP was revised to document those BMPs and detections declined afterward.

For bacterial risk during construction Collier described a case where a portable toilet blew over and discharged into a drainage feature. Corrective steps included relocating toilets at least 100 feet from drains, adding containment trays and anchoring, documenting service intervals, instituting daily observations, and removing portable toilets when permanent restroom facilities were available.

For new facilities Collier urged early assessment of receiving-water status: if a receiving water is PCB-impaired, a developer should specify non‑PCB dielectric fluids (for example, modern transformer fluids based on vegetable oil) and document that choice in the SWIP to support a claim that the pollutant of impairment is not present on site.

Across examples Collier emphasized three practical points: implement BMPs appropriate to the pollutant and site, monitor for the pollutant of concern or an agreed surrogate, and document inspections, maintenance and corrective actions in the SWIP. "Documentation is extremely important," he said, noting that missing records often undermine defenses during inspections.