title: Design and application of a direct-push vadose zone gravel permeameter.
abstract: A borehole permeameter is well suited for testing saturated hydraulic conductivity (K(sat)) at specific depths in the vadose zone. Most applications of the method involve fine-grained soils that allow hand auguring of test holes and require a small water reservoir to maintain a constant head. In non-cohesive gravels, hand-dug test holes are difficult to excavate, holes are prone to collapse, and large volumes of water are necessary to maintain a constant head for the duration of the test. For coarse alluvial gravels, a direct-push steel permeameter was designed to place a slotted pipe at a specific sampling depth. Measurements can be made at successive depths at the same location. A 3790 L (1000 gallons) trailer-mounted water tank maintained a constant head in the permeameter. Head in the portable tank was measured with a pressure transducer and flow was calculated based on a volumetric rating curve. A U.S. Bureau of Reclamation analytical method was utilized to calculate K(sat). Measurements with the permeameter at a field site were similar to those reported from falling-head tests.
authors.affiliation: Department of Biosystems and Agricultural Engineering, Oklahoma State University, Stillwater, OK 74078, USA.
authors.forename: Ronald B
authors.initials: RB
authors.lastname: Miller
authors.forename: Derek M
authors.initials: DM
authors.lastname: Heeren
authors.forename: Garey A
authors.initials: GA
authors.lastname: Fox
authors.forename: Daniel E
authors.initials: DE
authors.lastname: Storm
authors.forename: Todd
authors.initials: T
authors.lastname: Halihan
mesh_terms: D004784:Environmental Monitoring; D008962:Models, Theoretical; D014872:Water Movements