ALTERNATIVE COMPLIANCE MEASURES – ARE THEY REALLY EFFECTIVE?

POTWs want to reduce silver loadings to their headworks for a variety of reasons. Some are facing—or may soon face—stricter effluent limits for silver. The Code of Management Practices for Silver Dischargers, the CMP, was developed to cover a large number of users with limited POTW resources. The three-year study was conducted specifically to determine whether the CMP would be effective in reducing the amounts of silver loads discharged to POTWs by causing silver users to increase the level of pretreatment. The results of the study show that compliance with the CMP can costeffectively reduce silver loads to POTWs. Four POTWs have documented loading reductions of 20 percent to 52 percent over historical baselines after implementation of the CMP. Two POTWs documented average loading reductions of 37 percent and 63 percent respectively, using alternative approaches.