Control Measure Selection Criteria
A number of specific control measures for copper and nickel wastes have been developed for each of the metal finishing sites in the Palo Alto service area. From detailed studies of each site, the project team proposed several copper discharge control measures as being reasonable for adoption by all circuit board and metal finishing firms in the Palo Alto RWQCP service area. These measures apply to plating, cleaning, or etching baths, as well as to rinses, and treatment units.
Criteria used to select the reasonable control measures are:
- Economical - Are both low-cost (defined as being affordable from the company's current operating profits supplemented by project financing) and cost-effective (defined as having a simple payback equal to or less than the operating life of the process in which the measure is used - typically 3 to 5 years);
- Effective - Directly reduce copper discharges themselves, or significantly improve effectiveness of other "primary" measures that do reduce metals discharges;
- Easy To Use - Work without requiring significant operator interaction (in contrast to active measures that would depend solely upon operator attention);
- Widely Applicable - Are applicable to more than one firm;
- Proven - Are already in use in similar applications at other firms in the Palo Alto RWQCP service area or elsewhere;
- Low Impact - Have the least impact upon current shop operations (e.g., in terms of added floor space, additional workers needed, training required, new chemicals, and utilities);
- Safe - Introduce no additional safety issues beyond those shop personnel are already accustomed to dealing with; and
- Environmentally Sound - To the extent possible, avoid shifting waste streams to another medium (e.g., improving sewer discharges while increasing contaminant levels in treatment plant sludges).