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Nutrients National Synthesis Project

BIBLIOGRAPHY

Updated February 2010

Alexander, Richard B., Boyer, E.W., Smith, R.A., Schwarz, G.E., and Moore, R.B., 2007, The role of headwater streams in downstream water quality: Journal of the American Water Resources Association, v. 43, no. 1, p. 41-59.

Alexander, R.B., Brakebill, J.W., Brew, R.E., and Smith, R.A., 1999, ERF1--Enhanced River Reach File 1.2, U.S. Geological Survey Open-File Report 99-457, Reston, Virginia.

Alexander, Richard B., Elliott, Alexander H., Shankar, Ude, and McBride, Graham B., 2002, Estimating the sources and transport of nutrients in the Waikato River Basin, New Zealand: Water Resources Research, vol. 38, no.12, 1268, doi:10.1029/2001WR000879.

Alexander, Richard B., Johnes, Penny J., Boyer, Elizabeth W., and Smith, Richard A., 2002, A comparison of models for estimating the riverine export of nitrogen from large watersheds: Biogeochemistry, vol. 57, no. 58, p. 295- 339.

Alexander, Richard B., Slack, James R., Fitzgerald, A.S., and Schertz, T.L., 1997, Data from selected U.S. Geological Survey national stream water quality monitoring networks: Water Resources Research, vol. 34, no. 9, p. 2401-2405.

Alexander, R.B., Slack, J.R., Ludtke, A.S., Fitzgerald, K.K., and Schertz, T.L., 1997, Data from selected U.S. Geological Survey national stream water- quality monitoring networks (WQN) on CD-ROM: U.S. Geological Survey Fact Sheet FS-013-97, 2 p.

Alexander, R.B., Smith, R.A., Focazio, M.J., and Horn, M.A., 1999, Source-area characteristics of large public surface-water supplies in the conterminous United States: An information resource for source-water assessment, U.S. Geological Survey Open-File Report 99-248.

Alexander, R.B., Smith, R.A., Focazio, M.J., and Horn, M.A., 1999, Source-Area Characteristics of Large Public Surface-Water Supplies in the Conterminous United States: An Information Resource for Source-Water Assessment, U.S. Geological Survey Fact Sheet 160-99, Reston, Virginia.

Alexander, Richard B., Smith, Richard A., and Schwarz, Gregory E., 2000, Effect of stream channel size on the delivery of nitrogen to the Gulf of Mexico: Nature, vol. 403, February 17, 2000, p. 758-761.

Alexander, Richard B., Smith, Richard A., Schwarz, Gregory E., Boyer, Elizabeth W., Nolan, Jacqueline V., and Brakebill, John W., 2007, Differences in Phosphorus and Nitrogen Delivery to The Gulf of Mexico from the Mississippi River Basin: Environmental Science and Technology, v. 42, no. 3, p. 822-830.

Alexander, Richard B., Smith, Richard A., Schwarz, Gregory E., Preston, Stephen D., Brakebill, John W., Srinivasan, Raghavan, and Pacheco, Percy A., 2000, Atmospheric nitrogen flux from the watersheds of major estuaries of the United States: An application of the SPARROW watershed model: American Geophysical Union, p. 119-170.

Battaglin, W.A., Aulenbach, B.T., Vecchia, A., and Buxton, H.T., 2010, Changes in streamflow and the flux of nutrients in the Mississippi-Atchafalaya River Basin, USA, 1980–2007: U.S. Geological Survey Scientific Investigations Report 2009–5164, Reston, Virginia, 48 p.

Brezonik, P.L., Bierman, V.J., Alexander, R., Anderson, J, Barko, J., Dortch, M., Hatch, L., Keeney, D., Mulla, D., Smith, V., Walker, C., Whitledge, T., and W. Wiseman, W., 1999, Effects of reducing nutrient loads to surface waters within the Mississippi River Basin and the Gulf of Mexico, Report of Task Group 4 to the White House Committee on Environment and Natural Resources, Hypoxia Work Group, Federal Register, 64, 23834-23835.

Burkart, M.R., and Stoner, J.D., 2001, Nitrogen in groundwater associated with agricultural systems in Follett, R.F. and Hatfield, J.L., eds., Nitrogen in the Environment: Elsevier, p. 123-145.

Burow, K.R., Nolan, B.T., Rupert, M.G., and Dubrovsky, N.M., 2010, Nitrate in groundwater of the United States, 1991-2003, Environmental Science and Technology, vol. 44, no. 13, p. 4988-4997, doi: 10.1021/es100546y.

Clark, G.M., Mueller, D.K., Mast, M.A., 2000, Nutrient concentrations and yields in undeveloped basins of the United States: Journal of the American Water Resources Association, vol. 36, no. 4, p. 849-860.

Duff, J.H., Tesoriero, A.J., Richardson, W.B., Strauss, E.A., and Munn, M.D., 2008, Whole-stream response to nitrate loading in three streams draining agricultural landscapes: J. Environ. Qual. 37, doi:10.2134/jeq2007.0187.

Domagalski, J.L.; Ator, S., Coupe, R., McCarthy, K., Lampe, D., Sandstrom, M., Baker, N., 2008, Comparative study of transport processes of nitrogen, phosphorus, and herbicides to streams in five agricultural basins, USA: J.Environ. Qual 37, doi:10.2134/jeq2007.0408.

Foran, J., Brosnan, T., Connor, M., Delfino, J., DePinto, J., Dickson, K., Humphrey, H., Novotny, V., Smith, R., Sobsey, M., and Stehman, S., 2000, A framework for comprehensive, integrated, watershed monitoring in New York City: Environmental Monitoring and Assessment, 62 (2), p. 147-167.

Frederick, K.D. and Schwarz, G.E., 1999, Socioeconomic Impacts of Climate Change on U.S. Water Supplies, Journal of the American Water Resources Association, 35, 6, 1563-1583.

Fuhrer, G.J., Gilliom, R.J., Hamilton, P.A., Morace, J.L., Nowell, L.H., Rinella, J.F., Stoner, J.D. and Wentz, D.A., 1999, The quality of our nation's water: nutrients and pesticides: U.S. Geological Survey Circular 1225, 82 p.

Gilliom, R.J., Mueller, D.K., and Nowell, L.H., 1998, Methods for comparing water-quality conditions among National Water-Quality Assessment Study Units, 1992-1995: U.S. Geological Survey Open-File Report 97-589, 54 p.

Graffy, E.A., Helsel, D.R., and Mueller, D.K., 1996, Nutrients in the Nation's water: Identifying problems and progress: U.S. Geological Survey Fact Sheet FS-218-96, 6 p.

Green, C.T., Fisher, L.H., and Bekins, B.A., 2008, Nitrogen fluxes through unsaturated zones in five agricultural settings across the United States: J. Environ. Qual. 37, doi:10.2134/jeq2007.0010.

Green, C.T., Puckett, L.J., Bohlke, J.K., Bekins, B.A., Phillips, S.P., Kauffman, L.J., Denver, J.M., and Johnson, H.M., 2008, Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States: J. Environ. Qual. 37, doi:10.2134/jeq2006.0419.

Hamilton, Pixie A., and Helsel, Dennis, R., 1994, Effects of agricultural activities on ground-water quality in five regions of the United States, [abs.]: Proceedings AWRA 1994 Annual Summer Symposium of the American Water Resources Association, Effects of human-induced change on hydrologic systems, June 26-29, 1994, Jackson Hole, Wyoming, p. 1163.

Helsel, Dennis R., 1995, Nitrate in the Nation's waters [abs.]: A summary of recent studies: Water Resources Update, no. 101, Autumn 1995, p. 12-17.

Hitt, K.J., 1994, Refining 1970's land-use data with 1990 population data to indicate new residential development: U.S. Geological Survey Water-Resources Investigations Report 94-4250, 15 p.

Hitt, K.J., and Nakagaki, N., 2002, National Water-Quality Assessment study-unit investigations in the conterminous United States 1991-2001.

Hitt, K.J., and Nakagaki, N., 2002, National Water-Quality Assessment study-unit investigations in the conterminous United States 2001-2012.

Hitt, K.J. and Nolan, B.T., 2005, Nitrate in ground water: Using a model to simulate the probability of nitrate contamination of shallow ground water in the conterminous United States: U.S. Geological Survey Scientific Investigations Map 2881.

Hitt, K.J., Ruddy, B.C., and Stoner, J.D., 1999, [abstract] Potential Exposure of the Nation's waters to animal manure: Workshop abstracts-Animal feeding operations: Effects on hydrologic resources and the environment, August 30 - September 1, 1999, Ft. Collins, Colorado, U.S. Geological Survey Open-File Report 00-024, 107 p.

Hughes, W.B., E.J. Reuber, and L.J. Puckett, Fate of nitrogen in ground water in a coastal plain agricultural setting, Orangeburg County, South Carolina, South Carolina Water-Quality Conference, 1999.

Kolpin, Dana, Hallberg, George, Sneck-Fahrer, Debra, and Libra, Robert, 1997, Agricultural chemicals in Iowa's ground water, 1982-95¾What are the trends? U.S. Geological Survey Fact Sheet FS-116-97, 4 p.

Litke, D.W., 1999, Review of phosphorus control measures in the United States and their effects on water quality: U.S. Geological Survey Water-Resources Investigations Report 99-4007, 38 p.

Malone, R.W., Jaynes, D.B., Ma, L., Nolan, B.T., Meek, D.W., and Karlen, D.L., Soil-test N recommendations augmented with PEST-optimized RZWQM simulations, Journal of Environmentl Quality, vol. 39, no. 5, p. 1711-1723, doi: 10.2134/jeq2009.0425.

McMahon, P.B., and Chapelle, F.H., 2007, Redox Processes and Water Quality of Selected Principal Aquifer Systems: Ground Water, Volume 46, Number 2, March-April 2008, pp. 259-271(13), doi: 10.1111/j.1745-6584.2007.00385.x.

McMahon, P. B., Bohlke, J. K., Kauffman, L. J., Kipp, K. L., Landon, M. K., Crandall, C. A., Burow, K. R., and Brown, C. J., 2008, Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States: Water Resoures Research, 44, W04401, doi:10.1029/2007WR006252.

Mueller, D.K., 1998, Quality of nutrient data from streams and ground water sampled during 1993-95¾National Water-Quality Assessment Program: U.S. Geological Survey Open-File Report 98-276, 25 p.

Mueller, D.K., and Helsel, D.R., 1996, Nutrients in the Nation's waters¾Too much of a good thing?: U.S. Geological Survey Circular 1136, 24 p.

Mueller, D.K., and Spahr, N.E., 2005, Water-Quality, Streamflow, and Ancillary Data for Nutrients in Streams and Rivers Across the Nation, 1992-2001: U.S. Geological Survey Data Series 152.

Mueller, D.K. and Spahr, N.E., 2006, Nutrients in streams and rivers across the Nation--1992-2001: U.S. Geological Survey Scientific Investigations Report 2006-5107, 44 p.

Mueller, D.K., and Stoner, J.D., 1998, Identifying the potential for nitrate contamination of streams in agricultural areas of the United States in Proceedings of the National Water-Quality Monitoring Conference, July 7-9, 1998, Reno, Nev., p. III-163 to III-173.

Mueller, David K. and Titus, Cindy J., 2005, Quality of Nutrient Data from Streams and Ground Water Sampled During Water Years 1992-2001: U.S. Geological Survey Scientific Investigations Report 2005.5106, 27 p.

Mueller, D.K., Hamilton, P.A., Helsel, D.R., Hitt, K.J., and Ruddy, B.C., 1995, Nutrients in ground water and surface water of the United States¾Analysis of data through 1992: U.S. Geological Survey Water-Resources Investigations Report 95-4031, 74 p.

Mueller, D.K., Martin, J.D., and Lopes, T.J., 1997, Quality-control design for surface-water sampling in the National Water-Quality Assessment Program: U.S. Geological Survey Open-File Report 7-223, 17 p.

Mueller, D.K., Ruddy, B.C., and Battaglin, W.A., 1993, Relation of nitrate concentrations in surface water to land use in the upper- midwestern United States, 1989-1990, in Goolsby, D.A., Boyer, L.L., and Mallard, G.E., compilers, Selected papers on agricultural chemicals in water resources of the midcontinental United States: U.S. Geological Survey Open-File Report 93-418, p. 41-50.

Mueller, D.K., Ruddy, B.C., and Battaglin, W.A., 1994, Nitrate and atrazine in surface waters of the Upper-Midwestern United States: An example of regional synthesis, [abs.], in Sorenson, Stephen K., ed., 1994, Proceedings abstracts American Water Resources Association's symposium on the National Water-Quality Assessment Program--November 7-9, 1994, Chicago, Illinois: U.S. Geological Survey Open-File Report 94-397, p. 7.

Mueller, D.K., Ruddy, B.C., and Battaglin, W.A., 1997, Logistic model of nitrate in streams of the upper-midwestern United States: Journal of Environmental Quality, v. 26, no. 5, p. 1223-1230.

Munn, Mark D., and Hamilton, Pixie A., 2003, Effects of nutrient enrichment on stream ecosystems--New studies initiated by the U.S. Geological Survey: Briefing materials prepared for the Ecological Society of America Annual Meeting, Savannah, Georgia, August 2003, 4 p.

Munn, Mark D., and Hamilton, Pixie A., 2003, New studies initiated by the U.S. Geological Survey--Effects of nutrient enrichment on stream ecosystems-- U.S. Geological Survey Fact Sheet 03-118

Nolan, B.T., 1998, Modeling approaches for assessing risk of non-point contamination of ground water: U.S. Geological Survey Open-File Report 98-531, 22 p.

Nolan, B.T., 1999, Nitrate behavior in ground waters of the southeastern United States: Journal of Environmental Quality, vol. 28, no. 5, Sep.-Oct. 1999, p. 1518-1527.

Nolan, B.T., 2001, Relating nitrogen sources and aquifer susceptibility to nitrate in shallow ground waters of the United States: Ground Water, vol. 39, no. 2, March-April 2001, p. 290-299.

Nolan, Bernard T., 2005, Moving from monitoring to prediction - national assessment of nitrate in ground water: Handout for a Congressional Briefing in Washington, D.C., March 11, 2005, sponsored by the Water Enviornment Federation, Environmental and Energy Study Institute, and USGS, 4 p.

Nolan, B.T., and Hitt, K.J., 2002, Nutrients in shallow ground waters of beneath relatively undeveloped areas in the conterminous United States: U.S. Geological Survey Water-Resources Investigations Report 02-4289, 17 p.

Nolan, B.T., and Hitt, K.J., 2006, Vulnerability of shallow groundwater and drinking-water wells to nitrate in the United States: Environmental Science and Technology, vol. 40, no. 24, p. 7834-7840.

Nolan, B.T., and Ruddy, B.C., 1996, Nitrate in ground waters of the United States¾Assessing the risk: U.S. Geological Survey Fact Sheet FS-092-96, 4 p.

Nolan, B.T., and Stoner, J.D., 2000, Nutrients in ground waters of the conterminous United States, 1992-1995: Environmental Science and Technology, vol. 34, no. 7, p. 1156-1165.

Nolan, B.T., Baehr, A.L., and Kauffman, L.J., 2003, Spatial Variability of Groundwater Recharge and its Effect on Shallow Groundwater Quality in Southern New Jersey: Vadose Zone Journal, vol. 2, no. 4, p. 677-691.

Nolan, B.T., Bayless, E.R., Green, C.T., Garg, S., Voss, F.D., Lampe, D.C., Barbash, J.E., Capel, P.D., and Bekins, B.A., 2005, Evaluation of Unsaturated-Zone Solute-Transport Models for Studies of Agricultural Chemicals: USGS Open-File Report 2005-1196.

Nolan, B.T., Healy, R.W., Tabera, P.E., Perkins, K., Hitt, K.J., and Wolock, D.M., 2006, Factors influencing ground-water recharge in the eastern United States: Journal of Hydrology, v. 322, p. 187-205.

Nolan, B.T., Hitt, K.J., and Ruddy, B.C., 2002, Probability of nitrate contamination of recently recharged groundwaters in the conterminous United States: Environmental Science and Technology, vol. 36, no. 10, p. 2138-2145.

Nolan, B.T., Puckett, L.J., Ma, Liwang, Green, C.T., Bayless, E.R., and Malone, R.W., Predicting unsaturated zone nitrogen mass balances in agricultural settings of the United States, Journal of Environmental Quality, vol. 39, no. 3, p. 1051-1065, doi: 10.2134/jeq2009.0310.

Nolan, B.T., Ruddy, B.C., Hitt, K.J., and Helsel, D.R., 1997, Risk of nitrate in ground waters of the United States¾A national perspective: Environmental Science and Technology, v. 31, n. 8, p. 2229-2236.

Nolan, B.T., Ruddy, B.C., Hitt, K.J., and Helsel, D.R., 1997, Nitrate contamination of ground waters in the United States¾Evaluating the risk: U.S. Geological Survey poster.

Nolan, B.T., Ruddy, B.C., Hitt, K.J., and Helsel, D.R., 1998, A national look at nitrate contamination of groundwaters: Water Conditioning and Purification, v. 39, no. 12, p. 76-79.

Nolan, B.T., Ruddy, B.C., Hitt, K.J., and Helsel, D.R., 1998, Risk of nitrate contamination in groundwaters of the United States-A national perspective, version 2.0.

Nolan, B.T., Ruddy, B.C., Hitt, K.J., and Helsel, D.R., 1998, Nitrate in ground waters of the United States. in Proceedings of the National Water-Quality Monitoring Conference, July 7-9, 1998, Reno, Nev.

Porter, S.D., Mueller, D.K., Spahr, N.E., Munn, M.D., and Dubrovsky, N.M., 2008, Efficacy of algal metrics for assessing nutrient and organic enrichment in flowing waters (p 1036-1054) Freshwater Biology, v. 53, issue 5, DOI: 10.1111/j.1365-2427.2007.01951.x.

Puckett, L.J., 1994, Estimates of Nonpoint- and point source loadings of nutrients in NAWQA basins: What can they tell us? [abs.], in Sorenson, Stephen K., ed., 1994, Proceedings abstracts American Water Resources Association's symposium on the National Water-Quality Assessment Program- -November 7-9, 1994, Chicago, Illinois: U.S. Geological Survey Open-File Report 94-397, p. 6.

Puckett, L.J., 1994, Nonpoint-and point-source contributions of nitrogen and phosphorus in large watersheds, [abs.]: American Geophysical Union 1994 Fall Meeting, December 5-9, 1994, San Francisco, California, p. 228.

Puckett, L.J., 1994, Nonpoint and point sources of nitrogen in major watersheds of the United States: U.S. Geological Survey Water-Resources Investigations Report 94-4001, 6 p.

Puckett, L.J, 1995, Identifying the major sources of nutrient water pollution: Environmental Science and Technology, v. 29, n. 9, p. 408-414A.

Puckett, L.J., 1999, The effectiveness of riparian buffer zones for removing nitrate from groundwater discharging to Atlantic Coastal Plain streams, Sixth Symposium on Biogeochemistry of Wetlands, 1999.

Puckett, L.J., 2004, Hydrogeologic controls on the transport and fate of nitrate in ground water beneath riparian buffer zones: results from thirteen studies across the United States: Water Science and Technology, vol. 49, no. 3, p. 47-53.

Puckett, L.J., Alexander R.B., and Hitt, K.J., 1998, County-based estimates of nitrogen and phosphorus content of animal manure in the United States for 1982, 1987, and 1992, version 1.0.0.

Puckett, L.J., and Cowdery, T.K., 2002, Transport and fate of nitrate in a glacial outwash aquifer in relation to ground-water age, land use practices and redox processes: Journal of Environmental Quality, vol. 31, no. 3.

Puckett, L.J., Cowdery, T.K., Lorenz, D.L., and Stoner, J.D., 1999, Estimation of nitrate contamination of an agro-ecosystem outwash aquifer using a nitrogen mass-balance budget: Journal of Environmental Quality, volume 28, no. 6, Nov.-Dec. 1999, p. 2015-2025.

Puckett, L.J., Cowdery, T.K., McMahon, P.B., Tornes, L.H., and Stoner, J.D., 2002, Using chemical, hydrologic, and age dating analysis to delineate redox processes and flow paths in the riparian zone of a glacial outwash aquifer-stream system: Water Resources Research, vol. 38, no. 8.

Puckett, L.J., and Hughes, W.B., 2005, Transport and Fate of Nitrate and Pesticides: Hydrogeology and Riparian Zone Processes: Journal of Environmental Quality, vol. 34, no. 6, p. 2278-2292.

Puckett, L.J., Tesoriero, A.J., and Dubrovsky, N.M., 2011, Nitrogen Contamination of Surficial Aquifers--A Growing Legacy: Environmental Science and Technology, vol. 42, no. 3, p. 839-844.

Puckett, L.J., and Triska, F.J., editors, 1996, U.S. Geological Survey nitrogen cycling workshop, Denver, Colo., October 30 - November 2, 1995: U.S. Geological Survey Open-File Report 96-477, 88 p.

Puckett, Larry J., Zamora, C., Essaid, H., Wilson, J.T., Johnson, H.M., Brayton, M.J., and Vogel, J.R., 2008, Transport and fate of nitrate at the ground-water-surface-water interface: J. Environ. Qual. 37, doi:10.2134/jeq2006.0550.

Ruddy, B.C., Lorenz, D. L., and Mueller, D. K., 2006, County-level estimates of nutrient inputs to the land surface of the conterminous United States, 1982-2001: USGS Scientific Investigations Report 2006-5012, 17 p.

Rupert, M.G., 2008, Decadal-scale changes of nitrate in ground water of the United States, 1988-2004: J. Environ. Qual. 37, doi: 10.2134/jeq2007.0055.

Sauer, T.J., Alexander, R.B., Brahana, J.V., and Smith, R.A., 2001, The importance and role of watersheds in the transport of nitrogen in Follett, R.F., and Hatfield, J.L., eds., Chapter 7 Nitrogen in the Environment, p. 147-181.

Smith, R.A. and Alexander, R.B., 2000, Sources of nutrients in the Nation's watersheds, Proceedings of the National Resource, Agriculture, and Engineering Service, A conference for nutrient management consultants, extension educators, and producer advisors, March 28-30, 2000, Camp Hill, Pennsylvania.

Smith, Richard A., Alexander, Richard B., Tasker, Gary D., Price, Curtis V., Robinson, Keith W., White, Dale A., 1993, Statistical modeling of water quality in regional watersheds: Watershed '93, p. 751-754.

Smith, R.A., Schwarz, G.E., and Alexander, R.B., 1997, Regional interpretation of water-quality data: Water resources Research, Vol. 33, No. 12, p. 2781-2798.

Sorenson, S.K., Porter, S.D., Akers, K.K.B, Harris, M.A., Kalkhoff, S.J., Lee, K.E., Roberts, L.R., and Terrio, P.J., 1999, Water quality and habitat conditions in Upper Midwest streams relative to riparian vegetation and soil characteristics, August 1997: Study design, methods and data: U.S. Geological Survey Open-File Report 99-202, 53 p.

Spahr, N.E., Dubrovsky, N.M., Gronberg, J.M., Franke, O.L., and Wolock, D.M., 2010, Nitrate loads and concentrations in surface-water base flow and shallow groundwater for selected basins in the United States, water years 1990-2006: U.S. Geological Survey Scientific Investigations Report 2010-5098, 39 p.

Spahr, N.E., Mueller, D.K., Wolock, D.M., Hitt, K.J., and Gronberg, J.M., 2010, Development and application of regression models for estimating nutrient concentrations in streams of the conterminous United States, 1992-2001: U.S. Geological Survey Scientific Investigations Report 2009-5199, 22 p.

Sprague, L.A., Mueller, D.K., Schwarz, G.E., and Lorenz, D.L., 2009, Nutrient trends in streams and rivers of the United States, 1993-2003: U.S. Geological Survey Scientific Investigations Report 2008-5202, 196 p.

Sprague, L.A., and Lorenz, D.L., 2009, Regional nutrient trends in streams and rivers of the United States, 1993-2003: Environmental Science and Technology, v. 43, p. 3430-3435.

Squillace, Paul J., Scott, Jonathon, Moran, Michael J., Nolan, B.T., and Kolpin, Dana W., 2002, VOCs, pesticides, nitrate, and their mixtures in groundwater used for drinking water in the United States: Environmental Science & Technology, vol. 36, no. 9, p. 1923-1930.

Stoner, J.D., and Goolsby, D.A., 1999, [abstract], Stream nutrients findings from national and regional water-quality assessments: U.S. Department of Agriculture Workshop-"Agricultural and Coastal Resources: Issues in Measuring the Economic Dimensions of Problems and Policies," Washington DC, June 3, 1999.

Tesoriero, A.J., Saad, D.A., Burow, K.R., Frick, E.A., Puckett, L.J., and Barbash, J., 2007, Linking ground water age and chemistry data along flow paths: implications for trends and transformations of nutrients and pesticides: Journal of Contaminant Hydrology, vol. 94, p. 139-155.

Tornes, L.H., Puckett, L.J., Stoner, J.D., and Brigham, M.E., 1994, The effect of riparian wetlands in reducing nitrate-nitrogen from a sand and gravel aquifer to a stream, [abs.] poster: American Geophysical Union 1994 Fall Meeting, December 5-9, 1994, San Francisco, California, p. 261.

Ward, M. H., deKok, T.M., Levallois, P., Brender, J., Gulis, G., Nolan, B.T., and VanDerslice, J., 2005, Drinking-Water Nitrate and Health--Recent Findings and Research Needs: Environmental Health Perspectives, vol. 113, no. 11, p. 1607-1614.

Webb, R.T., Wieczorek, M.E., Nolan, B.T., Hancock, T.C., Sandstrom, M.W., Barbash, J.E., Bayless, E.R., Healy, R.W., and Linard, Joshua, 2008, Variations in pesticide leaching related to land use, pesticide properties, and unsaturated zone thickness: J. Environ. Qual. 37, doi:10.2134/jeq2007.0245.

Wilber, William G., and Davis, Jerri V., 1994, Assessing the quality of the Nation's water¾Point versus nonpoint sources of phosphorus in rivers: U.S. Geological Survey Yearbook, Fiscal Year 1993, p. 48-49.