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</LabelSeparator><Level>1</Level><ElementName>us-gaap_AssetRetirementObligationDisclosureAbstract</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText /><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>xbrli:stringItemType</ElementDataType><SimpleDataType>string</SimpleDataType><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Asset Retirement Obligation Disclosure [Abstract]</Label></Row><Row FlagID="0"><Id>2</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

</LabelSeparator><Level>2</Level><ElementName>us-gaap_AssetRetirementObligationDisclosureTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2013-01-01to2013-03-31" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;A reconciliation of the aggregate carrying amount of asset
retirement obligations is as follows:&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

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    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;&lt;b&gt;March 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="text-align: center; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;&lt;b&gt;December 31,&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1pt solid; text-align: center; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;&lt;b&gt;2013&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="border-bottom: black 1pt solid; text-align: center; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;&lt;b&gt;2012&lt;/b&gt;&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom"&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td colspan="2" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="width: 78%; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Balance, beginning of year&lt;/font&gt;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;$&lt;/font&gt;&lt;/td&gt;
    &lt;td style="width: 8%; text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;225,881&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%; text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="width: 1%; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;$&lt;/font&gt;&lt;/td&gt;
    &lt;td style="width: 8%; text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;130,397&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="width: 1%; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Liabilities assumed on acquired properties&lt;/font&gt;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;-&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;75,396&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Liabilities settled&lt;/font&gt;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;(168,582&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;)&lt;/font&gt;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;(3,271&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Accretion expense&lt;/font&gt;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;1,433&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;18,171&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Revision of existing liabilities&lt;/font&gt;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1pt solid; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1pt solid; text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1pt solid; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1pt solid; text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;5,188&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: white"&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="vertical-align: bottom; background-color: #CCEEFF"&gt;
    &lt;td style="line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;Balance at End of Period&lt;/font&gt;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt double; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;$&lt;/font&gt;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt double; text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;58,732&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="text-align: right; line-height: 115%"&gt;&amp;#160;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt double; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;$&lt;/font&gt;&lt;/td&gt;
    &lt;td style="border-bottom: black 1.5pt double; text-align: right; line-height: 115%"&gt;&lt;font style="font: 8pt Times New Roman, Times, Serif"&gt;225,881&lt;/font&gt;&lt;/td&gt;
    &lt;td nowrap="nowrap" style="line-height: 115%"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;
&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;The Company recorded an accretion expense of $1,433 and $
1,176 for the three months ended March 31, 2013 and March 31, 2012, respectively.&lt;/p&gt;</NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>The entire disclosure for an asset retirement obligation and the associated long-lived asset. An asset retirement obligation is a legal obligation associated with the disposal or retirement from service of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 410

 -SubTopic 20

 -Section 50

 -Paragraph 1

 -URI http://asc.fasb.org/extlink&amp;oid=6392692&amp;loc=d3e7535-110849



Reference 2: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Accounting Standards Codification

 -Topic 410

 -SubTopic 20

 -Section 50

 -Paragraph 2

 -URI http://asc.fasb.org/extlink&amp;oid=6392692&amp;loc=d3e7569-110849



Reference 3: http://www.xbrl.org/2003/role/presentationRef

 -Publisher FASB

 -Name Statement of Financial Accounting Standard (FAS)

 -Number 143

 -Paragraph 22

 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



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