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<oai_dc:dc xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd">
  <dc:creator>C. D. Farrar</dc:creator>
  <dc:date>1980</dc:date>
  <dc:description>&lt;p&gt;The Hop·; area includes about 3,200 mi&lt;sup&gt;2&lt;/sup&gt; in northeastern Arizona ~nd is mostly in the Navajo and Hopi Indian Reservations; about 400 mi of the area is south of the Navajo Indian Reservation boundary . Ground water occurs in several aquifers that are made up of one or more formations; the composite stratigraphic column indicates the relative position of the formations. The main sources of ground water are the Coconino aquifer, the Chinle Formation. the N and D aquifers, the Toreva and Bidahochi Formations, and the alluvium. The aquifers are separated by fine-grained rock units that inhibit the vertical movement of ground water.&lt;/p&gt;&lt;p&gt;Ground-water development has been slight, and the water is used mainly for public, domestic, and livestock supplies. In 1977 about 425 acre-ft of ground water was withdrawn in the Hopi area. The amount of ground water withdrawn annually is small compared to the potential recharge from precipitation; therefore, water levels generally are not affected by pumping from wells.&lt;/p&gt;&lt;p&gt;Because the ground-water system in the Hopi area has not been changed greatly by development, a large number of water-level measurements and water-quality data collected prior to 1977 are used in this report to show conditions in 1977. A few water-level measurements were made south of the Navajo Indian Reservation boundary in 1977. &lt;/p&gt;&lt;p&gt;The hydrologic data on which these maps are based are available, fo~ the most part, ·in computer-printout form and may be consulted at.the Arizona Water Commission, 222 North Central Avenue, Suite 850, Phoenix, and at U.S. Geological Survey offices in: Federal Building, 301 West Congress Street, Tucson; Valley Center, Suite 1880, Phoenix; and 2255 North Gemini Drive, Building 3, Flagstaff. Material from which copies can be made at private expense is available at the Tucson, Phoenix, and Flagstaff offices of the U.S . Geological Survey. &lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.3133/ofr803</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>U.S. Geological Survey</dc:publisher>
  <dc:title>Maps showing ground-water conditions in the Hopi area, Coconino and Navajo counties, Arizona; 1977</dc:title>
  <dc:type>reports</dc:type>
</oai_dc:dc>