CLIENT NAME - Sarasota.WaterAtlas.org

via a 0.5-hp chemical metering pump. The chlorine discharge location is at thenorthern base of the ground storage tank. Chlorine doses vary throughout the year,as higher doses tend to be applied in the low-demand, hotter summer months thanduring the high-demand, cooler winter months.• Ammonia - Liquid ammonia is added for the formation of chloramines for residualdisinfection. Liquid ammonia (~18% solution) is stored in three 300-gallon tanks andis transferred to a 100-gallon day tank prior to dosing. Ammonia is fed through the topof the west side of the ground storage tank via a 0.5-hp chemical metering pump. Thetypical chlorine to ammonia ratio target is 5 to1, although facility staff stated that theactual ratio typically produced is 4 to 1. The target residual chlorine concentration is3.0 mg/L, and facility staff state that actual residuals in the reservoir range from 2.5 to3.5 mg/L, depending on season. County staff have expressed some concern of shortcircuitingand inadequate mixing in the tank due to the chemical feed injection points.Additionally, the tank is not equipped with recirculation piping or a mixing device.Further investigation should be initiated to confirm that primary disinfectionrequirements are being met and that optimum mixing and chloramine formation istaking place.It should be noted that the chemical delivery area at the University WTF is difficult fordelivery trucks to maneuver. The trucks must enter via a narrow driveway and have noparking lot or other space to turnaround on the property grounds. Therefore, delivery trucksmust back into the facility from University Parkway. University Parkway is a major citystreet, and trucks stopping and backing into the driveway creates dangerous conditions.County staff have stated their concern of the dangerous conditions for chemical delivery,and a larger chemical delivery area is desired. The facility’s septic tank drainfield is locatednext to the existing driveway preventing the construction of a turnaround area. If the facilitywere connected to the County’s sewer system, the septic tank and drainfield could bedecommissioned and a turnaround area could be constructed in this area.2.3.3.2 Treated Water Storage and DeliveryTreated water is stored in the onsite ground storage tank prior to delivery to the distributionsystem by Pump Station No. 1, which is also located at the University WTF site. Waterdischarged from the degasification system is blended in the tank with some of the waterreceived from Manatee County prior to being discharged to the tank. The typical blend ratiois 1 to 1, and normal flows are 1.2 mgd of both well water and Manatee County water. Theremaining Manatee County water flows through the bypass pipe to obtain the 5 to 1 blendratio discussed in Section 2.3.3.County staff stated that the tank is kept at an almost constant, full level in order to minimizeshort-circuiting and to maximize mixing in the tank. The tank is not equipped with mixers,FINAL - August 31, 2005 39H:\Client\SAR Co_SAR\6873C00 WATER SUPPLY MASTER PLAN UPDATE\Deliverables\TM 2 - Water System Assets\Final\TM2 Final.doc