Specifications include, but are not limited to: 1. The polymer must perform equal to or better than the below minimum requirements, and any other requirements specified in this Scope of Services, when the centrifuge is operating at a throughput of approximately 150 gpm and an overall 2 to 5% total solids (TS) feed solids with a target range of approximately 2.5-3.8% TS. Products exhibiting “medium to high molecular weight” and “high charge” have usually been able to achieve that standard. • Maximum polymer dosage: 20 lbs bone dry active polymer per bone dry ton of solids dewatered. • Minimum sludge cake solids: 30%, with volatile solids content of approximately 60 to 70%. • Minimum Solids Recovery: 95%. • Polymer shall be non-toxic to the process biomass and receiving stream and shall not contain any PCBs. • Concentrations of heavy metals and other metals in the polymer makeup must be equal to or below those for polymer used in drinking water treatment as described in NSF/ANSI 61. • The polymer batches shall be made with Plant Effluent Water (PEW). • Polymer shall be readily biodegradable. The County can, at its option, perform a biodegradability test with the biomass that is currently utilized at the plant. The test will require at least 95% cBOD5 degradation within 1.5 hours. The approximate F/M (food to mass) ratio will be 0.6 at the beginning of the test.