SEDIMENT CHEMISTRY--Contamination from D-77 Samplers Equipped with Solenoid-Actuated Valves In Reply Refer To: February 2, 1990 WGS-Mail Stop 412 OFFICE OF WATER QUALITY TECHNICAL MEMORANDUM 90.07 Subject: SEDIMENT CHEMISTRY--Contamination from D-77 Samplers Equipped with Solenoid-Actuated Valves The Office of Water Quality currently is sponsoring a study of possible trace-metal contamination associated with various water and suspended sediment samplers used by Water Resources Division personnel. The study shows that the D-77 sampler equipped with a solenoid-actuated valve contaminates samples with metals, including iron, lead, copper, zinc, and cadmium. Therefore, anyone requiring analyses of trace metals, either dissolved or associated with suspended sediments, should not use a D-77 sampler equipped with a solenoid-actuated valve. John Skinner of the St. Anthony Falls (Minnesota) Hydraulic Lab has developed a modified sampler to obviate this problem, but it has not yet been tested and evaluated under field conditions. Arthur Horowitz of the Georgia District will evaluate the efficacy of the modified sampler with respect to avoidance of trace-metal contamination. As soon as the results are available, they will be reported in a subsequent Office of Water Quality Technical Memorandum. The standard D-77 sampler without the solenoid-actuated valve still may be used for all applications. The few D-77 samplers with the solenoid-actuated valve still may be used for those applications that do not call for trace-metal analyses. Any questions about D-77 sampler contamination should be directed to Sidney Johnson, Office of Water Quality, FTS 959-6808. David A. Rickert Chief, Office of Water Quality This memorandum does not supersede any OWQ Technical Memorandum. Key Words: Contamination, Trace Metals, Samplers, Water Quality Distribution: A, B, PO, FO John Skinner Arthur Horowitz Project Office, Vancouver, Washington