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The following HTML text is provided to enhance online readability. Many aspects of typography translate only awkwardly to HTML. Please use the page image as the authoritative form to ensure accuracy. scale operations of about 200 people drinking from a system, to a large scale where thousands to tens of thousands of people are being exposed. Environmental Management System for Local Municipal Government EntitiesDan Askenaizer, of Montgomery Watson and Harza Engineering Company, asked whether EPA regional offices or headquarters are involved in the effort to encourage the use of an environmental management system for local municipal government entities. Dr. Macler answered that the programs are not really on the drinking water side. There are plans for hazardous materials. He thinks some of the utilities were looking to the effort to be relieved of regulatory burden. The federal level in Washington, D.C., has not really embraced the drinking water program. Therefore, he is unsure what the likelihood of persistence for the program will be. Research FundingMark Matsumoto, of the University of California at Riverside, acknowledged the discussions about the amount of dollars available for R&D going down in drinking water areas as well as the fact that few impacted agencies are able to provide the funds or have the funding to do the R&D necessary for their own research needs. He asked Dr. Macler what he sees as the near-term and long-term funding picture for government research. Dr. Macler affirmed the interesting situation in R&D. Looking at just EPA’s budget and the money that goes to the laboratories in Cincinnati for drinking water R&D, he said it goes down. At the same time, there are congressional line items where a congressman in Glendale provides $900,000 to the city for R&D, $750,000 for more R&D, and $2 million for still more R&D; it becomes evident where a lot of R&D is getting done. Dr. Macler said that the Metropolitan Water District has received a federal line item of $3.5 million for desalination research that he is overseeing. The district has to match it. EPA has about $6 million in desalination membranes, brine disposal, and pretreatment. There is money in other places, but no one is trying to bring the pieces together to make sure everyone is trying to reach one main goal. Money is available. In looking at the congressional line item, three or four years ago it was a few million dollars and now it is hundreds of millions. He added that there are a lot of $0.5 million to $2 million R&D projects that are supposed to go out for bid. PerchloratesMr. Matsumoto next mentioned the perchlorate debate as an example of the role of science with regard to setting limits. Dr. Macler referred to the Safe Drinking Water Act in which Congress said that water should essentially be without risk. This essentially means that if the risk is unknown, the worst case should be assumed. Often the data being used come from both human and animal studies. For example, for perchlorate, the studies are at the 200- to 300-ppb exposure level. That is the lowest observed adverse effect level. He said the study on humans was very short term in adults. The study on rats used multiple generations of rats and looked at the pups, fetuses, and pregnant mice. The data then have to be extrapolated to make some judgment for humans. A sensitive subpopulation for humans is pregnant women and infants, but studies cannot be done on these populations. Therefore, a conservative extrapolation must be made. For cancer, a linear approach is used to extrapolate downwards. For noncancer end points, uncertainty factors are used. Dr. Macler continued that if the limit is moved up an order of magnitude, the unknown risk is greater. The level might be legitimate, but the comfort level is reduced. He said that science can only go so far, and the risk assessment world has to make a determination. Risk assessors must be willing to take uncertainties into account. Eventually there is a management decision that takes into account the social aspect of the situation. Dr. Macler said that a possible reason for a perchlorate drinking water regulation is the Colorado River and the 34 million people that drink its water. If the risk is one in a million, this is equivalent to 34 people, which is unacceptable from the Safe Drinking Water Act standpoint. It would have been best if cleanup of the Colorado River had started five years ago. He said that some methodologies are being developed for cleanup of such sites that are not too expensive. Different Levels of Treatment for Different UsesDebbie Elcock, of Argonne National Laboratory, raised questions about having different levels of treatment for different uses. Based on the statutes and legislation, we know what the level should be for drinking water. Do we know what the level would be for different industrial uses or for agriculture? Water for these purposes would not have to be as treated. It might be economical to actually treat for the different levels for different uses. Is there the legislative authority to do that? Dr. Macler replied that treatment for industrial use would depend on the process and on whether the regulations were for environmental or occupational safety and health purposes. For agricultural purposes in California there are different watering requirements depending on the vegetation. Median strips along freeways are watered with different water than golf courses. If human exposure is more likely, the water quality must be better. Another consideration is whether plants can tolerate the water.
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