Site. The location of an observation, structure, object, or other thing, whether actual, virtual, abandoned, extant, or planned. SITE_##/SITEFILE_## Site identifier. A unique, two component string assigned to a site to identify it. Site name. SITEFILE_##.station_nm Absolute location. The exact spot on Earth where something exists. Water science center (WSC). A USGS office engaged in collecting and analyzing water information. Water science centers were formerly known as "districts". SITEFILE_##.district_cd Public land survey system (PLSS) area. A method used in the United States to survey and identify land parcels, particularly for titles and deeds of rural, wild or undeveloped land. SITEFILE_##.land_net_ds Map. A USGS topographical map. SITEFILE_##.map_nm Country. A political entity as defined by FIPS 10-4. COUNTRY Principal Administrative Division. FIPS 10-4 Principal Administrative Division: " For purposes of this standard, a principal administrative division is defined as an administrative area directly subordinate to the pertinent governing authority. Even though all principal administrative divisions within an entity may not be of equal rank, this Standard considers them as 'principal.' " STATE County. A United States county as defined by FIPS 6-4. COUNTY Hydrologic unit. Hydrologic unit. A hydrologic unit for which aggregate water-use data are stored. SITEFILE_##.huc_cd Agency site use. The site's data collection status. SITEFILE_##.agency_use_cd Basin. The drainage basin a site is located in. SITEFILE_##.basin_cd Site type. The type of feature at which a site is installed. SITEFILE_##.station_type_cd Topographic setting. The geomorphic features in the vicinity of the site. SITEFILE_##.topo_cd Data type. The type of data collected at a site. Instrument. A measurement instrument installed at a site. SITEFILE_##.instruments_cd Text. A string of characters and white space, comprising human readable text. SITEFILE_##.site_rmks_tx SITEFILE_##.inventory_dt Site time zone. The time zone a site is located in. SITEFILE_##.local_time_fg SITEFILE_##.construction_dt Data reliability. The reliability of the data available for a site. SITEFILE_##.reliability_cd Aquifer. The primary aquifer unit from which water is obtained from a ground water site. SITEFILE_##.aqfr_cd Site use. The use of the site or purpose for which the site was constructed (the former always holds precedence over the latter). SITEFILE_##.site_use_1_cd/SITEFILE_##.site_use_2_cd/SITEFILE_##.site_use_3_cd National aquifer. The primary national aquifer unit from which water is obtained from a ground water site. SITEFILE_##.nat_aqfr_cd Water Use site use. The type of water use at a site. SITEFILE_##.water_use_1_cd/SITEFILE_##.water_use_2_cd/SITEFILE_##.water_use_3_cd National water use category. A nationally designated category of functional water use at a site. SITEFILE_##.nat_water_use_cd Project number. The project that established a site. Record history. The points at which a database record was created and last modified, and the user names of the creators and modifiers. SITEFILE_##.site_cn/SITEFILE_##.site_cr/SITEFILE_##.site_mn/SITEFILE_##.site_md