the domes in about twenty minutes, entirely inside a sealed system to prevent dust particles from escaping into the surrounding environment. Water use Water is delivered by an elevated intake flume from the back channel of the St. Johns River to cool the station's condensers, after which the water is returned to the back channel. This cooling water does not mix with other liquid process streams while in contact with the condensers. Because Unit 2 has been out of service since 1983, the actual demand for cooling water by Northside Generating Station at full load since that time has been approximately 620 million U.S. gallons per day (Mgd), or per minute, to operate Units 1 and 3. Operation of the entire 3-unit plant occurred only from about 1978 until 1980. During that time, the demand for cooling water was approximately 827 Mgd ( per minute): 24.5% for Unit 1, 24.5% for Unit 2, and 51% for Unit 3. This amount of surface water supplied to the station was approximately 10% of the average flow passing through the back channel of the St. Johns River. Before passing through the condensers, noncontact cooling water at Northside Generating Station is treated intermittently with a biocide to prevent biological growth on the heat exchanger tubes. Sodium hypochlorite (NaOCl) and occasionally sodium bromide (NaBr) are used. Treatment occurs no more than 2 hours per day per operating unit. The St. Johns River Power Park taps into the discharge side of the Northside Generating Station condensers to obtain cooling tower makeup. The average surface water flow supplied to the Power Park heat rejection system is 50 Mgd ( per minute). Approximately 25% of this surface water evaporates into the atmosphere from the cooling towers. Cooling tower blowdown is routed back into Northside Generating Station's discharge collector basin. The daily average temperature of the cooling tower blowdown is limited to . Emissions Preliminary Emission Tests were conducted on Units 1 and 2 over the summer of 2002. Testing was conducted on both units burning coal and petroleum coke. Results are summarized in the table below. Emissions results from both units met all emission requirements for particulate, SO2, acid gases and heavy metals. Conflicts and controversies Soot coming from the JEA Northside Generating Station has prompted Distribution and Auto Services Inc. to threaten leaving Jacksonville area if the problem persists. Vehicle processing companies such as Auto Services Inc.