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everything it can through the water quality management program to improve the water quality for everyone in the region. This is why Zone 7 is encouraging the individual retailer to make the same changes that Zone 7 is in order to improve the water quality for everybody in the valley Ms. Ayala asked if he concurred that growth was paying for itself. Is there a decrease in quality because of growth? Mr. Marchand said he did absolutely concurred. It is a stated policy for Zone 7 for almost as long as he has been on the Board. He said there has been no decrease in water quality because of growth because Zone 7 did change the amount of water taken from the groundwater basin. In a gallon of water, there is approximately 1.2 grams of hardness. Every gallon that is pumped out of the basin has this hardness removed. What is recharged into the basin is State project water which has a hardness of approximately 280 milligrams per gallon or approximately one quarter. For every gallon pumped out, Zone 7 is charging the basin with less hard water. A decision was made as part of an early implementation of the salt management plan to increase the pumping of the groundwater basin to remove more salt to allow for greater recharge with softer State project water and remove the salts from the basin. It is called conjunctive use. Ms. Ayala asked about the quality of the water. Mr. Marchand said Water Factory 21 found after 30 years of recharging waste water it was were creating NDMA, N-Nitroso Dimethylamine, a known carcogenics going into the groundwater basin as 60 times the action level for the State of California. It grossly contaminated the groundwater basin. They were not looking for it and now that they are looking for it, they are using UV to remove it in its formation. Zone 7 does not have NDMA at 135 parts per billion in the water. He was at a Cai Poly water conference recently and spoke about this program. There were groups of engineers talking about potable and non-potable use and they agreed that RO is a technology that works. There is no problem with the technology if it works. Mr. Cusenza clarified that the City of Pleasanton wells now match the chlorine levels in those of Zone 7. That information was not included in the staff report. Mr. Marchand said this has been a cooperative process over the last two years, taking comments and working together and solving these problems. Ms. Hosterman said she felt it important to tackle the earthy, musty, chlorine tasting water and she is concerned about the health and safety of the water. She knows that trying to measure for different contaminants is not easy. She asked about cryptosporidium and target reduction of contaminant levels. One way of meeting this is to maintain the filtered water effluent turbidity below a specified low level and to assure a greater removal with a second process, such as ultraviolet disinfection, which is recommended to provide multi-barrier protection. How much does this cost and are we doing it? Pleasanton City Council 15 03/04/03 Minutes