A Suction Bailer for Sampling Very Thin Saturated Zones

摘要

A suction bailer is developed for the express purpose of sampling very thin perched water bodies (on the order of 1 cm thick) that may also be ephemeral. This device incorporates a semi-permeable membrane on the bottom of the bailer that allows water entry, while simultaneously blocking air. This design allows unattended sample collection, which is monitored with a simple pressure transducer. Three prototypes were constructed and tested; one is based on a commercial suction lysimeter, while the other two are fabricated from stainless steel. All three prototypes were shown to be capable of sampling thin layers of water on the order of 1 cm thick and operating unattended for extended periods to capture intermittent events. Sample sizes of 100-1,000 mL are possible depending on fluid availability. The design does not place any constraints on the depth of emplacement.