Aluminum Sulfate (Alum) is primarily used as a coagulant to settle out fine particles in the spent backwash water that comes from the gravity filters backwash cycle. Aluminum Sulfate is additionally used at TMWRF to precipitate phosphorous from the Phosphorous Rich Supernatant (PRS) process.  This process reduces phosphorous loading from the dewatering process and returns it to digesters for biosolids disposal. 

If approved, the City of Sparks would be directly purchasing alum from Thatcher Chemical utilizing the contract offered by the National Intergovernmental Purchasing Alliance (NIPA) which is a group purchasing organization similar to others used in the purchase of goods and services in the City of Sparks.  In this case, NIPA is marketing a contract originally bid and awarded by the City of Las Vegas for the provision of various water treatment chemicals, including Alum.  This practice allows the City to purchase the chemicals directly from the supplier without the requirement to go to formal bid, as allowed by NRS 332.115 and NRS 332.195.  The current NIPA contract rate is $375/ton.   The estimated annual cost for this contract is $295,000.00.

1.  The City Council can approve the purchase as outlined above.

2. The City Council can direct the Manager to have staff comptetitively bid the contract for alum.

I move to approve the purchase of aluminum sulfate from Thatcher Chemical Company at a unit price of $375/ton, using the joinder provision of the City of Las Vegas/National IPA contract #150063-SK-A., with an annual estimated cost of $295,000.