Vertical coordinate information is referenced to the North American Vertical Datum of 1988 (NAVD 88). Horizontal coordinate information is referenced to the North American Datum of 1983 (NAD 83). Altitude, as used in this report, refers to distance above the vertical datum.

Plates 1-2. Maps showing: la. Location of wells and surface-water sampling sites. Ib. Nitrite-plus-nitrate nitrogen concentrations and fecal indicator bacteria in samples collected at surface-water sites. 2. Nitrite-plus-nitrate nitrogen concentration in groundwater samples, and wells where fecal indicator bacteria were detected in water samples.

No abstract

No abstract

For more information on the USGS-the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment, visit http://www.usgs.gov or call 1-888-ASK-USGS For an overview of USGS information products, including maps, imagery, and publications, visit http://www.usgs.gov/pubprodTo order this and other USGS information products, visit http://store.usgs.gov Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.Although this report is in the public domain, permission must be secured from the individual copyright owners to reproduce any copyrighted materials contained within this report. Tables Table 1. Simplified geologic units defined in this study and correlation with previous investigations …………………………………………………………………… 7 Table 2. Hydrogeologic units defined in this study and correlation with geologic units defined in this study and previous investigations ………………………………… 9 Well-Numbering SystemWells in Washington State are assigned a local well number that identifies each well based on its location within a township, range, section, and 40-acre tract. For example, local well number 33N/04E-02E01 indicates that the well is in township 33 north of the Willamette Base Line, and range 4 east of the Willamette Meridian. The numbers immediately following the hyphen indicate the section (02) within the township, and the letter following the section (E) gives the 40-acre tract of the section. The two-digit sequence number (01) following the letter is used to distinguish individual wells in the same 40-acre tract. A "D" following the sequence number indicates a well that has been deepened. In the plates of this report, wells are identified using only the section and 40-acre tract, such as 02E01; the township and range are shown on the map borders.