A 10,000+ ton university district cooling loop had known underground piping leaks, continuous nitrite top-up to ground, weekly manual handling of a skin-sensitizing biocide, and a deteriorating microbiological and corrosion profile. A capital pipe-replacement project was on the table — along with EPA discharge exposure of $103,445–$293,445 per day, per incident.
Continuous nitrite addition was required to replace inhibitor inventory lost to underground piping leaks — meaning nitrite-laden water was being discharged continuously to soil and groundwater, representing a potential EPA reportable incident at $103,445–$293,445 per day, per incident.
Weekly manual top-up of an Isothiazolin biocide — a known skin sensitizer — was creating splash exposure risk for maintenance staff, with inadequate engineering controls in place.
Baseline water chemistry data was trending in the wrong direction: corrosion rate 2.5 mpy (well above acceptable limits for a closed system), ATP 560 RLU indicating active microbiological growth, and nitrite inhibitor residual degrading approximately 50% over 20 days rather than holding stable.
A capital piping replacement project estimated at $500,000+ was under active consideration as the only path forward.
Designed a two-phase program rehabilitation inside the plant's hard constraints — no system drain, no flush, no shutdown of the cooling loop, no disruption to campus cooling service.
Phase 1: Applied a non-foaming biodispersant to progressively mobilize biofilm and corrosion deposits from pipe walls, paired with a graduated filtration step-down by pore size to capture and remove mobilized material without plugging system components.
Phase 2: Replaced the nitrite/Isothiazolin program with a non-nitrite, non-phosphate organic corrosion inhibitor — selected specifically for compatibility with the campus stormwater discharge profile and significantly safer for routine maintenance handling.
Independent program rehabilitation design for closed chilled water, district cooling, and campus loops. No chemistry sold. No shutdown required in most cases.