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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;(12)&amp;#160;Other Non-current Liabilities&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt; text-indent: 4%"&gt;&lt;i&gt;Other non-current liabilities &lt;/i&gt;consisted of the following:
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       &lt;td nowrap="nowrap" align="center" colspan="6" style="border-bottom: 1px solid #000000"&gt;&lt;b&gt;December 31,&lt;/b&gt;&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Self insured workers&amp;#8217; compensation obligations
   &lt;/div&gt;&lt;/td&gt;
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       &lt;td align="left"&gt;$&lt;/td&gt;
       &lt;td align="right"&gt;32,989&lt;/td&gt;
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       &lt;td&gt;&amp;#160;&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Black lung obligations
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       &lt;td align="right"&gt;30,334&lt;/td&gt;
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       &lt;td align="right"&gt;1,732&lt;/td&gt;
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       &lt;td&gt;
   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Acquired coal supply agreements, net
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       &lt;td align="right"&gt;20,202&lt;/td&gt;
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       &lt;td align="right"&gt;&amp;#8212;&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Derivative financial instruments
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       &lt;td align="right"&gt;28,366&lt;/td&gt;
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       &lt;td align="right"&gt;44,741&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Income taxes
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       &lt;td align="right"&gt;13,960&lt;/td&gt;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Deferred production tax
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Other
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;&amp;#160;
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;Total other non-current liabilities
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   &lt;div style="margin-left:15px; text-indent:-15px"&gt;&amp;#160;
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