<?xml version='1.0' encoding='utf-8'?>
<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:contributor>A. L. Ishii</dc:contributor>
  <dc:creator>Robert G. Striegl</dc:creator>
  <dc:date>1989</dc:date>
  <dc:description>&lt;p&gt;&lt;span&gt;The distribution of CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;in unsaturated glacial and eolian deposits adjacent to buried low-level radioactive waste was measured, and movement of the gas from the waste source was simulated using a two-dimensional finite-difference model for gas diffusion in the unsaturated zone. Mean&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;was greatest (1.56 Pa) in a pebbly-sand deposit 11.6 m below the land surface and 12 m from the waste, and generally decreased with increased horizontal distance from the waste. Mean&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;was least (0.07 Pa) at depth of 1.8 m below land surface, regardless of distance from the waste.&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;at the land surface averaged 0.17 Pa. Depth versus&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;profiles suggest consumption of both waste-produced and atmospheric CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;in the upper unsaturated zone, presumably by methanotrophic microorganisms. Numerical simulations of methane movement support the consumption observation; inclusion of a term in the model for consumption of CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;in the upper 2 m of the unsaturated zone resulted in simulated&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;within 30% of mean&amp;nbsp;&lt;/span&gt;&lt;i&gt;P&lt;/i&gt;&lt;span&gt;CH&lt;/span&gt;&lt;sub&gt;4&lt;/sub&gt;&lt;span&gt;&amp;nbsp;at eleven of thirteen sampling locations. A similar fit of the data was obtained for only four locations when consumption was not considered.&lt;/span&gt;&lt;/p&gt;</dc:description>
  <dc:format>application/pdf</dc:format>
  <dc:identifier>10.1016/0022-1694(89)90256-4</dc:identifier>
  <dc:language>en</dc:language>
  <dc:publisher>Elsevier</dc:publisher>
  <dc:title>Diffusion and consumption of methane in an unsaturated zone in north-central Illinois, U.S.A.</dc:title>
  <dc:type>article</dc:type>
</oai_dc:dc>