Income Taxes	9 Months Ended
Feb. 28, 2014
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Income Taxes	Income Taxes Income taxes for the interim periods ended February 28, 2014 and 2013 have been included in the accompanying financial statements on the basis of an estimated annual rate. The tax rate differs from the 35% federal statutory corporate rate primarily due to percentage depletion that is tax deductible, state income taxes and valuation allowances against deferred tax assets. The estimated annualized rate is 5.4% for fiscal year 2014 compared to 7.9% for fiscal year 2013. We received income tax refunds of $0.4 million in the nine-month period ended February 28, 2014 and none in the nine-month period ended February 28, 2013. We made no income tax payments in the nine-month periods ended February 28, 2014 and 2013. Net deferred tax assets totaled $5.0 million at February 28, 2014 and $6.7 million at May 31, 2013. Net deferred tax assets classified as current were $14.2 million at February 28, 2014 and $18.8 million at May 31, 2013. Management reviews our deferred tax position and in particular our deferred tax assets whenever circumstances indicate that the assets may not be realized in the future and records a valuation allowance unless such deferred tax assets are deemed more likely than not to be recoverable. The ultimate realization of these deferred tax assets depends upon various factors including the generation of taxable income during future periods. The Company’s deferred tax assets exceeded deferred tax liabilities as of February 28, 2014 and May 31, 2013 primarily as a result of recent losses. Management has concluded that the sources of taxable income we are permitted to consider do not assure the realization of the entire amount of our net deferred tax assets. Accordingly, a valuation allowance is required due to the uncertainty of realizing the deferred tax assets. We will continue to record additional valuation allowance against additions to our net deferred tax assets for fiscal year 2014 until management believes it is more likely than not the deferred tax assets will be realized. The amount of income tax we pay is subject to ongoing audits by federal and state authorities which may result in proposed assessments. We adjust reserves for our uncertain tax positions due to changing facts and circumstances, such as the closing of a tax audit, judicial rulings, refinement of estimates, or realization of earnings or deductions that differ from our estimates. To the extent that the final outcome of a matter differs from the amount recorded, such difference generally will impact our provision for income taxes in the period that includes its final resolution. Reserves for uncertain tax positions including related interest and penalties were not material at February 28, 2014 or May 31, 2013. In addition to our federal income tax return, we file income tax returns in various state jurisdictions. We are no longer subject to income tax examinations by federal and state tax authorities for years prior to 2009. The Internal Revenue Service completed their review in fiscal year 2013 of our federal income tax returns for 2007 through 2010 resulting in no adjustments.

Income Taxes

Income taxes for the interim periods ended February 28, 2014 and 2013 have been included in the accompanying financial statements on the basis of an estimated annual rate. The tax rate differs from the 35% federal statutory corporate rate primarily due to percentage depletion that is tax deductible, state income taxes and valuation allowances against deferred tax assets. The estimated annualized rate is 5.4% for fiscal year 2014 compared to 7.9% for fiscal year 2013. We received income tax refunds of $0.4 million in the nine-month period ended February 28, 2014 and none in the nine-month period ended February 28, 2013. We made no income tax payments in the nine-month periods ended February 28, 2014 and 2013.

Net deferred tax assets totaled $5.0 million at February 28, 2014 and $6.7 million at May 31, 2013. Net deferred tax assets classified as current were $14.2 million at February 28, 2014 and $18.8 million at May 31, 2013. Management reviews our deferred tax position and in particular our deferred tax assets whenever circumstances indicate that the assets may not be realized in the future and records a valuation allowance unless such deferred tax assets are deemed more likely than not to be recoverable. The ultimate realization of these deferred tax assets depends upon various factors including the generation of taxable income during future periods. The Company’s deferred tax assets exceeded deferred tax liabilities as of February 28, 2014 and May 31, 2013 primarily as a result of recent losses. Management has concluded that the sources of taxable income we are permitted to consider do not assure the realization of the entire amount of our net deferred tax assets. Accordingly, a valuation allowance is required due to the uncertainty of realizing the deferred tax assets. We will continue to record additional valuation allowance against additions to our net deferred tax assets for fiscal year 2014 until management believes it is more likely than not the deferred tax assets will be realized.

The amount of income tax we pay is subject to ongoing audits by federal and state authorities which may result in proposed assessments. We adjust reserves for our uncertain tax positions due to changing facts and circumstances, such as the closing of a tax audit, judicial rulings, refinement of estimates, or realization of earnings or deductions that differ from our estimates. To the extent that the final outcome of a matter differs from the amount recorded, such difference generally will impact our provision for income taxes in the period that includes its final resolution. Reserves for uncertain tax positions including related interest and penalties were not material at February 28, 2014 or May 31, 2013.

In addition to our federal income tax return, we file income tax returns in various state jurisdictions. We are no longer subject to income tax examinations by federal and state tax authorities for years prior to 2009. The Internal Revenue Service completed their review in fiscal year 2013 of our federal income tax returns for 2007 through 2010 resulting in no adjustments.