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The vacuum within the Sampler causes the water to move froth the oil, through the pores of the porous ceramic cup, and into the San ler. The rate at which the soil solution will collect within the Sa ler depends on the capillary conductivity of the soil, the soil suct on value within the soil (as measured with tensiometers), and the mount of vacuum within the Saingler. In moist soils of good con ctivity, at field capacity (10 to 30 cb of sail suction as read on ate siometer) substantial soil water samples can be collected wit n a few hours. Under more difficult conditions it may require seve al days to collect an adequate sample. Recovering a Sample from In g neral, a vacuum of 50 to 85 cb is normally applied to the Soil the Soil Water Sampler Wat r Sampler. In very sandy soils, however, it has been noted that ery high vacuums applied to the Soil Water Sampler seem to resu t in a lower rate of collection of the sample than a lower vacu m. It is our opinion that in these coarse, sandy soils, the high vacu m within the Sampler may deplete the moisture in the im- medi to vicinity of the porous ceramic cup reducing the capillary cond ctivity, which creates a barrier to the flow of water to the cup, n loams and gravelly clay loams, users have reported collec- tion f 300 to 500 ml of solution over a period of a day with an appli d vacuum of 50 cb, when soils are at field capacity. At waste Ovate disposal sites, users have obtained 1500 ml of sample solu- tion i 24 hours following cessation of irrigation with 1 to 2 inches of w to water on sandy or clay loam soil. To re from the (see Feg~re ever a soil water sample, remove the Pressure-Vacuum tube he vacuum port of the pump, and attach the tube to the re port. Place the discharge access tube in a small collection and remove both clamping rings. Apply a few strokes on the rump to develop enough pressure within the Sampler to force lected water out of the Sampler and into the collection bottle g. 11). 1900N~ uent samples are collected by again creating a vacuum the Sampler and following the steps as outlined above. SOILMOISTURE EQUIPMENT CORP. 14 / \® PO. Box 30025, Sonto 8orboro, Colifornio 93105 USA II / \ Phone:(8051964-3525~Foa: (8051683-2189 SoLLM\ olsro2e e-moil: solesQsoilmoisture.mm ~ Web: http://wwwsoilmo sture.<om ~/