Stormwater Administrative Order on Consent and Toxicity Monitoring Assistance

Prior to the current MS4 NPDES permit, an EPA audit of the Port of Stockton’s whole effluent toxicity monitoring activities in conjunction with MS4 NPDES permit program highlighted a comprehensive list of deficiencies in toxicity monitoring resulting in issuance of an Administrative Order of Consent (AOC) that contained stringent requirements for the Port. RBI reviewed the draft AOC, prepared written comments and proposed changes that put forth more reasonable and attainable requirements, and negotiated stormwater toxicity monitoring requirements for the AOC. In support of maintaining compliance with the AOC and directing toxicity identification evaluations, RBI performed an ongoing technical review of bioassay laboratory reports, as well as, a detailed review and comments for the renewed MS4 NPDES permit issued by the Central Valley Regional Water Board. RBI also prepared documentation of the Port’s stormwater control activities and rationale/findings of compliance with state and federal antidegradation policies for the Regional Water Board’s use in the permit renewal.