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<br />') <br /> <br />) <br /> <br />Each NAWC generator will only emit 6 grams of <br />silver iodide per hour. This minute amount of <br />material is spread over a large area such that <br />the seeding material becomes undetectable by even <br />the most sensitive chemical analysis techniques a <br />few tens of miles downwind (Warburton, et al., <br />1979) . <br /> <br />The question of the potential for a reduction in <br />precipitation downwind of the target area is often <br />raised regarding weather modification programs. <br />The National Science Foundation funded a workshop <br />in 1977 to examine this question. Quoting from a <br />summary of this workshop (Brown, et al., 1978)... <br /> <br />"The "better quality" evidence available from <br />mostly a posteriori analyses of past <br />randomized seeding programs suggests that <br />precipitation changes in extended areas tend <br />to be of the same sign (increases or <br />decreases) and roughly the same magnitude as <br />the primary "target area" effects. <br /> <br />There is currently little evidence available <br />to support the "Robbing Peter to pay Paul" <br />hypothesis that seeding to increase rain in <br />one area will deprive some other area of its <br />normal rainfall. However, the data base is <br />inadequate to rule out the possibility that <br />such a combination might occur." <br /> <br />The objective as stated in question a is to <br />beneficially increase precipitation in the target <br />area. If snowpack accumulation reaches a level <br />where additional precipitation would be considered <br />to be no longer beneficial, then seeding <br />operations would be either suspended or <br />terminated. The proposed suspension criteria are <br />when the percent of normal snowpack reaches the <br />following values on the dates given: <br /> <br />0 200% on or about December 31 <br />0 175% on or about January 31 <br />0 150% on or about February 28 <br />0 140% on or about March 13 <br />0 135% on or about April 30 <br /> <br />Normal snowpack will be calculated by averaging <br />the actual Soil Conservation Service snowpack <br />readings for water content form representative <br />snow sites in the target area <br />