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.
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Independent program rehabilitation design for closed chilled water, district cooling, and campus loops. No chemistry sold. No shutdown required in most cases.