The U.S. Geological Survey (USGS) gathers data for determining the location, amount, availability, and quality of ground and surface water throughout the United States and its territories. About 75 to 80 percent of the water-quality samples used in this effort are analyzed by the National Water Quality Laboratory (NWQL).
The NWQL determines organic and inorganic constituents in samples of ground and surface water, river and lake sediment, aquatic plant and animal material, and precipitation collected in the United States and its territories by the USGS. In fiscal year 1996-1997, the NWQL produced about 1,440,000 analytical results for approximately 55,000 samples.
Most of the samples analyzed at the NWQL are the result of cooperative projects between the USGS and other Federal, State, and local agencies. In addition to cooperative projects, congressionally mandated programs such as the National Water-Quality Assessment (NAWQA) Program send samples to the Laboratory. The NAWQA Program was established (1) to describe the status of the Nation's water resources, (2) to identify and describe trends in the Nation's water resources, and (3) to develop an understanding of the natural and human factors affecting water quality.
To manage the workload, the NWQL employs approximately 160 full-time employees. A few students are also employed part-time through Federal Stay-In-School and Cooperative Education Programs.
Programs or units within the NWQL must coordinate their efforts to effectively receive, analyze, review, and release sample data. Initially, all samples received by the NWQL must pass through the Log-In Unit, where they are unpacked, labeled, and sent to the analytical areas for analysis. Generally, the samples are sent to either the Organic Chemistry Program or the Inorganic Chemistry Program where the samples are prepared and analyzed according to customer requests.(1) (2) (3)
(1) A physical science technician operates chromatographic cleanup columns during sample preparation. (2) An analyst in the Low Ionic Strength Unit uses a personal computer to operate a graphite furnace. The equipment can be used to start or stop a sample analysis, calibrate standards, and develop methods. (3) View of the Trace Metals Unit showing automated hydride analysis system and atomic absorption instrumentation.
The Organic Chemistry Program receives samples for the determination of insecticides, herbicides, and industrial organic compounds. The program consists of seven units: (1) Carbon, (2) Liquid Chromatography, (3) Gas Chromatography of Water, (4) Gas Chromatography of Sediment and Tissue, (5) Mass Spectrometry of Volatiles, (6) Mass Spectrometry of Semivolatiles, and (7) Solid-Phase Extraction. Samples are prepared for analysis within seven working days of receipt at the NWQL. After the analytical work has been completed, the results are delivered to the Computer Services Unit for computer entry.
The Inorganic Chemistry Program receives samples for the determination of metals, major anions and cations, nutrients, and physical properties. The program consists of five units: (1) Trace Metals, (2) Plasma, (3) Majors, (4) Low Ionic Strength, and (5) Nutrients. Samples submitted are processed by the units, and when completed, most of the inorganic data are transmitted electronically to the Computer Services Unit.
Analytical results for most of the samples received and analyzed at the NWQL are processed by the Computer Services Unit using the Laboratory Information Management System (LIMS). Results of custom analyses are reported to the customer by memorandum. All field and laboratory data related to each sample are entered into the LIMS computer. Once in the LIMS, the completed sample data are automatically run through the data review program, which calculates the ionic balance and sum of constituents, compares field and laboratory values, compares results for dissolved and total constituents, and indicates if a constituent concentration exceeds allowable drinking-water regulations. If a sample fails any one of these data-review checks, it is automatically flagged by the system and reviewed by the Quality Assurance Unit (QAU) of the Quality Management Program.
The Quality Management Program consists of the QAU, Radiochemistry Unit, U.S. Department of Defense Environmental Contamination (DODEC) Hydrology Program, Biological Quality Assurance/Quality Control Unit, and the Publications Office.
The QAU, in addition to other chemical logic checks, performs four basic functions: (1) data review, (2) resolution of customer inquiries, (3) administration of round-robin studies and laboratory certification reviews, and (4) administration, review, and resolution of quality-assurance and quality-control activities. To ensure that the NWQL can consistently provide its customers with reliable data, QAU personnel individually review all results that are rejected by the LIMS data-review program, with reanalysis of samples requested as appropriate. The QAU personnel also process requests for reanalysis and coordinate with NWQL and customers to resolve any problems or questions that may occur in the course of retrieval or interpretation of analytical data.
The Radiochemistry Unit (Radchem) coordinates an extensive network of contract laboratories for the determination of radiochemical and stable isotopes. In addition, Radchem in-house capabilities include determination of gross alpha, gross beta, laser uranium, and radon.
The DODEC Program primarily assesses the potential contamination at military bases at the request of the Department of Defense or the U.S. Environmental Protection Agency. The DODEC work is characterized by rigid quality-assurance requirements and the use of specific analytical methods that have been approved by the U.S. Environmental Protection Agency. The DODEC analytical work typically is sent to contract laboratories, which are carefully monitored and evaluated by the DODEC staff at the NWQL.
The Biological Quality Assurance/Quality Control Unit oversees the use of commercial laboratories to process samples collected by biologists with the NAWQA Program. Bioassessment contributes data on the species composition and relative abundance of aquatic organisms present in the NAWQA study areas. In cooperation with USGS offices, this unit can provide identification and quality-management services to other groups within USGS, and to State and Federal agencies.
The Publications Office processes, edits, and publishes all NWQL reports and journal articles. Reports processing embodies everything related to report production - from the inception of a project through delivery of a published document. The goal of the office is to prepare technically sound, editorially acceptable, error-free reports in a timely manner.
For those customers who are pursuing unique projects needing special or custom methods, the NWQL also maintains an active Methods Research and Development Program (MRDP) that works closely with the other programs to develop new methods or adapt current methods for special needs. The MRDP primarily consists of two units: (1) Organic Methods Development, and (2) Inorganic Methods Development. The MRDP is available for consultation and advice on issues involving project planning, sample collection, preservation, analysis, and interpretation of data.(4) (5) (6)
(4) A physical science technician in the Quality Assurance Unit prepares blind sample reference materials for the Inorganic Chemistry Program.
(5) A new laboratory robotics system in the Methods Research and Development Program has been developed for solid-phase extraction of trace concentrations of a broad range of pesticides from water samples.
(6) A waste control officer in the Safety Unit neutralizes hazardous waste prior to disposal.
The NWQL provides analytical services for water-quality determinations using a large, highly automated laboratory near Denver, as well as various contract laboratories. It serves national programs involved with water chemistry, water-resources issues and species identification of biological samples. Heightened concerns about water quality and about the possible effects of toxic chemicals at trace and ultratrace concentrations have contributed to an ongoing demand for the types of objectively obtained and analyzed data that the NWQL provides. The NWQL is committed to fulfilling USGS analytical requirements by providing high-quality results in a timely, cost-effective manner.
Water-quality laboratories of the U.S. Geological Survey have been associated with the Nation's rich heritage and rapid growth for more than 100 years. The Survey's water-quality activity can be traced to 1879 when the first chemical water-quality information was made available (Durum, 1978, p. 3).*
During 1918-73, the USGS established 22 water-quality laboratories nationwide. These facilities provided the analytical capability and water-quality information for hydrologic investigations and the national baseline inventory of chemical, physical, fluvial sediment, and biological characteristics of surface and ground water in the United States. During 1919-28, total annual production averaged about 750 samples (Durum, 1978, p. 2). Beginning in 1972, the major functions of the 22 laboratories were combined into three centralized laboratories, which in turn were combined into one comprehensive, highly automated facility in Denver in 1986.
The U.S. Geological Survey (USGS), a bureau of the U.S. Department of the Interior, was established by an act of Congress on March 3, 1879, to provide a permanent Federal agency to conduct the systematic and scientific "classification of the public lands and examination of the geologic structure, mineral resources, and the products of the national domain" (U.S. Congress, 1879).**
Since 1879, the research and fact-finding role of the USGS has grown and been modified to meet the changing needs of the Nation it serves. Specific responsibilities and programs carried out by the Geologic, National Mapping, Water Resources, Information Systems, and Administrative Divisions of the USGS serve a diversity of needs and uses that include the following:
assessing the Nation's energy and mineral resources; providing information to enable managers to mitigate the effects of natural hazards such as floods, earthquakes, volcanoes, landslides, and droughts; evaluating and monitoring the quantity, quality, and distribution of surface- and ground-water resources; operating national mapping programs; providing detailed and innovative map products; investigating the resource potential of the ocean floor in search of domestic source of critical and strategic minerals; and developing geologic and hydrologic criteria to aid regulatory agencies in selecting the best sites for the safe disposal of hazardous, radioactive, or other toxic wastes.
* Durum, W.H., 1978, Historical profile of quality of water laboratories and activities, 1879-1973: U.S. Geological Survey Open-File Report 78-432, 110 p.
** U.S. Congress, 1879, Appropriations Act of 1879 [Organic Act]:#43 United States Code 31(a), March 3.
Inquiries regarding NWQL analytical services and programs should be directed as follows:Chief, National Water Quality Laboratory