Specifications include, but are not limited to: Work on this project includes the purchase of chemicals to be used in the drinking water treatment process. 1. Prospective bidders proposing to supply any product other than those already approved for use in the Evanston Water Treatment Plant must run jar tests in Evanston’s lab on at least two separate occasions under the supervision of the Water Treatment Plant Chemist. Arrangements shall be made with, and at the convenience of, the Chemist. 2. Each occasion of testing shall be separated in time by change in season, to allow raw water conditions to change (e.g. temperature and turbidity). 3. Jar tests performed at each occasion shall include but not be limited to one control jar which has raw water only, nothing added, and one jar of raw water with the current dosage of alum and polymer presently being used in the plant. The other four jars shall be used to test the proposed product but changing only one variable per test run. 4. Test procedure and results must be clearly outlined and recorded and copies of this data must be submitted to the Chemist on the day of the test, even if a formal report with conclusions is to be submitted at a later date. 5. Minimum data required: mixer speeds, mix times, settling times, chemical dosage in mg/l, indicate whether chemical is fed neat or diluted. The foregoing are all variables to be tested separately as outlined in item 3. Alkalinity, Ph, turbidity, temperature and the time when the sample was taken shall also be recorded. 6. Observations of the presence of the first floc, relative size and its ability to settle shall be recorded. Turbidity of settled water shall also be recorded for all samples including control. 7. The laboratory jar test area and equipment shall be cleaned and returned to the condition it was found in by the person(s) conducting the test. 8. A sample of at least 500ml of each product tested shall be left for independent testing if the city desires.