FIELD GUIDE FOR COLLECTING AND PROCESSING STREAM-WATER SAMPLES FOR THE NATIONAL WATER-QUALITY ASSESSMENT PROGRAM

摘要: The U.S. Geological Survey's National Water-Quality Assessment program includes extensive data-collection efforts to assess the quality of Nation's streams. These studies require analyses stream samples for major ions, nutrients, sediments, and organic contaminants. For information be comparable among in different parts Nation, consistent procedures specifically designed produce uncontaminated trace analysis laboratory are critical. This field guide describes standard collecting processing contaminants, sediment, conductivity, pH, alkalinity, dissolved oxygen. Samples collected processed using modified newly equipment made Teflon avoid contamination, including nonmetallic samplers (D-77 DH-81) a sample splitter. Field solid-phase extraction developed process constituent an extracted with stabilized compounds more accurate results. Improvements operational include use chambers capsule filtering systems. A procedure carbon is contamination from cleaned methanol. Quality assurance maintained by strict procedures, replicate sampling, blank samples, rigid cleaning detergent, hydrochloric acid,