Water-Quality Field Methods?phaseout of US D-77 and frame-type samplers In Reply Refer To: Mail Stop 412 January 25, 2002 Office of Water Quality Technical Memorandum 2002.09 Subject: Water-Quality Field Methods phaseout of US D-77 and frame-type samplers The purpose of this memo is to begin the phaseout of the use of the US D-77 rigid-bottle and collapsible-bag samplers and the frame-type bag sampler for collection of water-quality and sediment samples. The US D-77 rigid-bottle sampler has been used for many years, although it is known to be difficult to use correctly because of the very small range in which it samples isokinetically and because it becomes unstable at relatively low velocities. The US D-77 bag and frame-type bag samplers have also been in use for a number of years; these samplers require field calibration each time they are used. The US DH-95, US D-95, and US D-96 isokinetic samplers were developed by the Federal Interagency Sedimentation Project (FISP) and subsequently approvedby the Interagency Technical Committee of the Subcommittee on Sedimentation. These samplers are currently for sale and provide the field with a well-tested and documented set of samplers that work in most sampling conditions. In addition to these samplers, the US XD-99 (275 lb) is in the testing phase and a lightweight bag sampler is in the design phase. The US DH-95 and US D-95 are rigid-bottle samplers with a maximum sampling depth of 15 feet. The US D-96 and US XD-99 are collapsible-bag samplers that have maximum sampling depths of 110 feet and 165 feet, respectively. Information about available samplers and ordering samplers can be found at http://fisp.wes.army.mil/. The Office of Water Quality, in concurrence with the Office of Surface Water, is recommending that the US D-77 rigid-bottle and bag samplers and the frame-type bag sampler be phased out for collection of water-quality and sediment samples. As funding permits, these samplers should be replaced with the newer samplers. The goal is to replace the discontinued samplers by the 2003 sampling season. If the US D-77 is currently being used, its limitations must be noted. See Office of Water Quality (Technical Memorandum 99.02) and the National Field Manual for Collection of Water-Quality Data (TWRI Book 9, Chapter 4.1)) for details on using isokinetic samplers. Instructions for the use of selected samplers can be found at http://fisp.wes.army.mil/Reports.htm. Questions about ordering samplers or the operation of samplers can be emailed to Wayne O'Neal [woneal@usgs.gov] at the FISP. Stephen K. Sorenson /s/ Acting Chief, Office of Water Quality This memorandum supersedes Office of Water Quality Technical Memoranda 81.02 and 90.07. Distribution: All WRD Employees (See attached file: OWQ.0209-D-77.phaseout.doc) ******************************** Stephen K. Sorenson Acting Chief, Office of Water Quality U.S. Geological Survey 412 National Center Reston, VA 20192 703/648-6864 sorenson@usgs.go