“…This study is intended to inform and guide changes to this policy. Willoughby, T.C., See, R.B., and Schroder, L.J., 1989, Stability of nitrate-ion concentrations in simulated deposition samples used for quality-assurance activities by the U.S. Geological Survey: U.S. Geological Survey Water-Resources Investigations Report 89-4042, 15 p. Yang, D., Goodison, B.E., and Metcalfe, J.R., 1998, Accuracy of NWS 8" standard nonrecording precipitation gauge-Results and application of WMO intercomparison: Journal of Atmospheric and Oceanic Technology, v. 15, p. 54-68. Yang, D., Goodison, B.E., Metcalfe, J.R., Louie, P., Leavesley, G.L., Emerson, D., Hanson, C.L., Golubev, E.E., Gunther, T., Pangburn, T., Kang, E., and Milkovic, J., 1999, Quantification of precipitation measurement discontinuity induced by wind shields on national gauges: Water Resources Research, v. 35, no.…”