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35~)8 7 .' Above the layers which confine the artesian aquifer, the sallds and gravels also bear water. This "unconfined" aquifer can be conc€'ived of as a 13.rge sponge on the surface of the Valley. The "sponge" is kept moist by sprinp, runoff fron the mountain slopes, irrigation diversions, and to a small degree by upward leakage from the artesian aqui fer. Like a dry sponge le[t on a wet kitchen counter, capillary action slowly di5tributes water through the who Ie system. The sponge becOl:les evenly dilr~p. In the sump area of the Closed Basin) the effect of the sun on the surface of the land is like a heat lar.lp being focused on our "sponp,e." The top surfa.ce feels dry but, in fact, water moves through it all the time and evaporates into the atmosphere. The Project is, quite simply, designed to capture SOr:1E' of this water before it evaporates. , A pipe appropriately slotted below the water table, wtlich is insert~d into the unconfined aquifer, will fill \IP with water to about the level of the water table. If the water is to reach the surface, it ffilltit be pu:nped. The Pr0ject wells are designed to work this way. Project effects to the uncon- fined aquifer are limited to the area within the Project boundries. This is the second way that the Project will mini~ize local economic effect. By law, the operation of the Project cannot lower tIle water table more than 2 feet outside the Project boundaries. Observation wells have heen established around the periphery of the Project area. Except for about 30 minl\tes a year to clear out sedi~ent~, these wells are not pumped at all. They are strictly there for allmving monthly mE'a5Urements of the water tRhle to be made. These measurements are a public record. The Project salvage wells inside the boundaries work by creating a drawdown in th~ water tahle (see fi~ure B-1). The design calls for them to be spaced and pumped at a rate .so that over the whole 130,00U-acr..:' Project area the water table will oe lowered by an average of 4 to 8 feet while not droppil1p, more than 2 feet at or beyonrl the boundaries. The water below and the ve~eta- tian on top or all land outside of the Project bondaries will not be signi- ficantly affected by the operation of the Project. Some people find the scale of SOT:'!e of the Project's stati!itics to be alarming (150 to ISO "ells, 130,000 acres of Project area, 104,000 acre-feet of y~arly salvaged water). In facti these statistics Sllould be reassuring. The Project design calls [or an average of less than one well per section. Virtually no place else in the Valley are wells 10 "idely spaced. The Project's planned 104,UOO acre-feet annual yield is tiny when cOr.lpared to tIle water produced by orlly the new center pivot systems introduced in the Valey for anyone year in the 1970's (see section VI, question 2). rhe reason that there are so Qany wells is because they will 6e widely spaced and each one will recover only relatively small amounts of water. This is the aspect of the Project's design \"hich allo\"9 only the amount of water to be salvaged which would evaporate naturally. The third aspect of the Project which relates to minimizing local economic effects has to do with the character of the land which is within the 130,000-acre Project boundaries. Water has continuously evaporated from the surface of the Closed Basin sump for centuries. The minerals dissolved in