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USD ($)

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MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;13.&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;td&gt;&lt;div align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Commitments and Contingencies&lt;/font&gt;&lt;/div&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&amp;#160;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Lease and Other Commitments&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In connection with the acquisition of the El Dorado Refinery, the Company entered into an operating sublease agreement with Shell for the use of the cogeneration facility at the El Dorado Refinery.&amp;#160;&amp;#160;The non-cancelable operating sublease, which has both a fixed and a variable component, expires in 2016, although the Company has the option to renew the sublease for an additional eight years.&amp;#160;&amp;#160;At the end of the renewal period, the Company has the option to purchase the cogeneration facility for the greater of fair value or $22.3 million.&amp;#160;&amp;#160;The Company also has building, equipment, aircraft and vehicle operating leases that expire from 2011 through 2017.&amp;#160;&amp;#160;Operating lease rental expense was approximately $14.0 million, $13.1 million, and $13.2 million for the years ended December 31, 2010, 2009 and 2008, respectively. The approximate future minimum lease payments for operating leases as of December 31, 2010 were $11.1 million for 2011, $7.6 million for 2012, $7.2 million for 2013, $6.5 million for 2014, $6.1 million for 2015 and $5.1 million thereafter.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;On December 2, 2009, the Company entered into a guaranteed throughput agreement with Rocky Mountain Pipeline System Inc. for the operation of its refined products pipeline from the Cheyenne Refinery to Sidney, Nebraska through December 31, 2012 with an annual tariff commitment of $1.6 million.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The approximate future commitments based on current crude oil pricing related to forward crude contracts with a fixed differential and a term of more than one year are $26.1 million in 2011, $51.8 million in 2012 and $38.2 million in 2013.&amp;#160;&amp;#160;The Company has crude oil terminalling and storage commitments for approximately $9.3 million in 2011, $9.9 million in 2012, $9.4 million each in 2013 and 2014, $8.6 million each in 2015 and 2016 and $7.8 million in 2017.&amp;#160;&amp;#160;The Company has commitments for crude oil pipeline capacity on four pipelines (see below) totaling approximately $38.2 million in 2011, $31.8 million in 2012, an average of $28.6 million for each of the years 2013 through 2015 and an average of $10.5 million for each of the years 2016 and 2017.&amp;#160;&amp;#160;The Company incurred expenses under these commitments of $48.2 million, $44.6 million and $41.1 million for the years ended December 31, 2010, 2009 and 2008, respectively.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company has two contracts for crude oil pipeline capacity on the Express Pipeline.&amp;#160;&amp;#160;The first contract, which began in 1997, is for 15 years and for an average of 13,800 barrels per day ("bpd") over that 15-year period.&amp;#160;&amp;#160;In December 2003, the Company entered into an expansion capacity agreement on the Express Pipeline for an additional 10,000 bpd from April 2005 through 2015.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company has a Transportation Services Agreement ("Agreement") to transport 38,000 bpd of crude oil based on filed tariffs on the Spearhead Pipeline from Flanagan, Illinois to Cushing, Oklahoma ("Cushing").&amp;#160;&amp;#160;This pipeline enables the Company to transport Canadian crude oil to the El Dorado Refinery.&amp;#160;&amp;#160;The initial term of this Agreement is until 2016, although the Company has the right to extend the Agreement for an additional ten-year term and increase the volume transported.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company entered into a definitive agreement with Rocky Mountain Pipeline System LLC, now owned by Plains All American Pipeline, L.P. ("Plains All American"), on March 31, 2006 to support construction of a new crude pipeline from Guernsey, Wyoming to Rocky Mountain's Fort Laramie, Wyoming tank farm and then&amp;#160;&amp;#160;to the Cheyenne Refinery.&amp;#160;&amp;#160;The Company made a ten-year commitment to ship 35,000 bpd based on a filed tariff on the new pipeline and will concurrently lease approximately 300,000 barrels of dedicated storage capacity in the Plains All American tank farm. The pipeline, which is designed to transport 55,000 bpd of heavy crude and is expandable to 90,000 bpd, first transported crude oil in October 2007.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company entered into an agreement with Osage Pipeline in 2007 to ship additional crude oil volumes from Cushing, Oklahoma to its El Dorado Refinery.&amp;#160;&amp;#160;The annual average increased commitment of 7,500 bpd commenced in July 2008 with a term of five years.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;On November 1, 2010, the Company's subsidiary, Frontier Oil and Refining Company ("FORC"), entered into a Master Crude Oil Purchase and Sale Contract ("Contract") with BNP Paribas Energy Trading GP and BNP Paribas Energy Trading Canada Corp. (collectively, "BNP").&amp;#160;&amp;#160;The maximum value of crude oil to be purchased under this Contract is $300.0 million.&amp;#160;&amp;#160;Under this Contract, BNP purchases, transports and subsequently sells crude oil to FORC at a location near Cushing, Oklahoma or other locations as agreed.&amp;#160;&amp;#160;Under this agreement, BNP is the owner of record of the crude oil as it is transported from the point of injection, typically Hardisty, Alberta, Canada, to the point of ultimate sale to FORC.&amp;#160;&amp;#160;The Company has provided a guarantee of FORC's obligations under this Contract, primarily to receive crude oil and make payment for crude oil purchases arranged under this Contract.&amp;#160;&amp;#160;The Company accounts for the transactions under this Contract as a financing arrangement, whereby the inventory and the associated liability are recorded in the Company's financial statements when the crude oil is injected into the pipeline in Canada.&amp;#160;&amp;#160;As of December 31, 2010, FORC and BNP had entered into certain commitments to purchase and sell crude oil in the first quarter of 2011 under this Contract; however, neither party has a continuing commitment to purchase or sell crude oil in the future.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;This Contract replaces the Company's crude oil purchase and sale contract with Utexam, a wholly-owned subsidiary of BNP Paribas Ireland ("Utexam Contract") which was terminated effective November 1, 2010.&amp;#160;&amp;#160;However, in accordance with the Utexam Contract, the rights and obligations of both Utexam and the Company arising from transactions entered into prior to the termination date will be completed.&amp;#160;&amp;#160;The Company anticipates any such transactions will be completed no later than the end of the first quarter of 2011.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Litigation&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold"&gt;Other.&lt;/font&gt;&amp;#160;&amp;#160;The Company is involved in various lawsuits and regulatory actions which are incidental to its business.&amp;#160;&amp;#160;In management's opinion, the adverse determination of such lawsuits would not have a material adverse effect on the Company's liquidity, financial position or results of operations.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Concentration of Credit Risk&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company has concentrations of credit risk with respect to sales within the same or related industries and within limited geographic areas.&amp;#160;&amp;#160;The Company sells its Cheyenne Refinery products, principally to independent retailers and major oil companies located primarily in the Denver, Colorado, western Nebraska and eastern Wyoming regions.&amp;#160;&amp;#160;The Company sells a majority of its El Dorado Refinery gasoline, diesel and jet fuel to Shell at market-based prices under a 15-year offtake agreement executed in conjunction with the purchase of the El Dorado Refinery in 1999.&amp;#160;&amp;#160;In 2010, Frontier retained and marketed 60,000 bpd of the El Dorado Refinery's gasoline and diesel production.&amp;#160;&amp;#160;Shell has also agreed to purchase all jet fuel production from the El Dorado Refinery through the offtake agreement term.&amp;#160;&amp;#160;The Company retains and markets all by-products produced from the El Dorado Refinery.&amp;#160;&amp;#160;The Company made sales to Shell of approximately $2.3 billion, $1.6 billion and $2.3 billion in the years 2010, 2009 and 2008, respectively, which accounted for 39%, 38% and 37% of consolidated refined products revenues in 2010, 2009 and 2008, respectively.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company extends credit to its customers based on ongoing credit evaluations.&amp;#160;&amp;#160;An allowance for doubtful accounts is provided based on the current evaluation of each customer's credit risk, past experience and other factors.&amp;#160;&amp;#160;The Company recorded a bad debt loss of $198,000 and a net increase in the allowance for doubtful accounts of $500,000 during the year ended December 31, 2009.&amp;#160;&amp;#160;No bad debts were recorded in the years ended December 31, 2010 and 2008.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block"&gt;&lt;br /&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt; FONT-WEIGHT: bold"&gt;Environmental&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company's operations and many of its manufactured products are specifically subject to certain requirements of the Clean Air Act ("CAA") and related state and local regulations.&amp;#160;&amp;#160;The 1990 amendments to the CAA contain provisions that will require capital expenditures for the production of cleaner transportation fuels and the installation of certain air pollution control devices at the Refineries during the next several years as discussed below.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Environmental Protection Agency ("EPA") has promulgated regulations requiring the phase-in of gasoline sulfur standards, which began January 1, 2004 and continued through 2008, with special provisions for small business refiners such as Frontier.&amp;#160;&amp;#160;As allowed by subsequent regulation, Frontier elected to extend its small refinery interim gasoline sulfur standard at each of the Refineries until January 1, 2011 by complying with the highway ultra low sulfur diesel standard by June 2006.&amp;#160;&amp;#160;The Company has reevaluated its initial strategy of capital investment at its Cheyenne Refinery to meet the new gasoline sulfur standard and is now planning to comply with these requirements starting January 1, 2011 for approximately five years through the redemption of gasoline sulfur credits.&amp;#160;&amp;#160;For long-term compliance, the Company expects to utilize internally generated credits and purchased credits and spend approximately $40.0 million ($18.4 million incurred as of December 31, 2010) for the FCCU gasoline hydrotreater project comprised of new process unit capacity and intermediate inventory handling equipment.&amp;#160;&amp;#160;In addition, new federal benzene regulations and anticipated state requirements for reduction in gasoline Reid Vapor Pressure ("RVP") suggest that additional capital expenditures may be required for environmental compliance projects.&amp;#160;&amp;#160;The Company is presently evaluating projects and the total potential cost in connection with an overall compliance strategy for the Cheyenne Refinery.&amp;#160;&amp;#160;Total capital expenditures as of December 31, 2010 for the El Dorado Refinery to comply with the final gasoline sulfur standard were approximately $95.0 million, including capitalized interest, and were completed in the fourth quarter of 2010.&amp;#160;&amp;#160;The $95.0 million of expenditures primarily related to the El Dorado Refinery's gasoil hydrotreater revamp project.&amp;#160;&amp;#160;The gasoil hydrotreater revamp project addressed most of the El Dorado Refinery's modifications needed to achieve gasoline sulfur compliance.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company is a holder of gasoline sulfur credits retained from prior generation years at both the Cheyenne and the El Dorado Refineries.&amp;#160;&amp;#160;There were no sulfur credit sales during the year ended December 31, 2010.&amp;#160;&amp;#160;During the year ended December 31, 2009 and 2008, Frontier sold sulfur credits for total proceeds of $1.9 million and $4.6 million, respectively, which are recorded in "Other revenues" on the Consolidated Statements of Operations.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In March 2009, settlement agreements associated with the EPA's National Petroleum Refining Enforcement Initiative were finalized and are now in effect.&amp;#160;&amp;#160;The Company currently estimates that, in addition to the flare gas recovery systems previously installed at each facility, capital expenditures totaling approximately $37.0 million ($662,000 incurred as of December 31, 2010) at the Cheyenne Refinery and $6.0 million ($1.5 million incurred as of December 31, 2010) at the El Dorado Refinery will need to be incurred prior to 2017.&amp;#160;&amp;#160;The Company may also choose to incur additional costs at the Cheyenne Refinery and at the El Dorado Refinery to comply with certain requirements of the agreement if such projects are determined to be the most cost effective compliance strategy.&amp;#160;&amp;#160;Notwithstanding these settlements, many of these same expenditures are required for the Company to comply with preexisting regulatory requirements or to implement its planned facility expansions.&amp;#160;&amp;#160;Consequently, the costs associated with these other projects are not included in the totals above.&amp;#160;&amp;#160;In addition, the settlement agreement provides for stipulated penalties for violations, which are periodically reported by the Company.&amp;#160;&amp;#160;Stipulated penalties under the decree are not automatic but must be requested by one of the agency signatories.&amp;#160;&amp;#160;As stipulated penalties are requested, the Company will separately report that matter and the amount of the proposed penalty, if material.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The EPA has promulgated regulations to enact the provisions of the Energy Policy Act of 2005 regarding mandated blending of renewable fuels in gasoline.&amp;#160;&amp;#160;The Energy Independence and Security Act of 2007 significantly increased the amount of renewable fuels that had been required by the 2005 legislation.&amp;#160;&amp;#160;The Company, as a small refiner, was exempt until January 1, 2011 from these requirements at which time it began incurring additional costs in order to meet the new requirements.&amp;#160;&amp;#160;The Company has renewable fuels blending facilities and purchases ethanol with Renewable Identification Numbers (RINs) credits attached.&amp;#160;&amp;#160;Ethanol RINs were created to assist in tracking compliance with these EPA regulations for the blending of renewable fuels.&amp;#160;&amp;#160;During the years ended December 31, 2010, 2009 and 2008, the Company sold RIN credits for $648,000, $4.6 million and $4.5 million, respectively, which were recorded in "Other revenues" on the Consolidated Statements of Operations.&amp;#160;&amp;#160;While not yet proposed or promulgated, other pending regulation regarding the mandated use of alternative or renewable fuels and/or the reduction of greenhouse gas emissions from either transportation fuels or manufacturing processes is under consideration by the EPA.&amp;#160;&amp;#160;In addition, the EPA has recently determined that greenhouse gases, including carbon dioxide, present a danger to human health and the environment, which may result in future regulation of such gases.&amp;#160;&amp;#160;If greenhouse gas control regulations are promulgated, these requirements could materially impact the operations and financial position of the Company (see "Other Future Environmental Considerations" below).&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;On February 26, 2007, the EPA promulgated regulations limiting the amount of benzene in gasoline.&amp;#160;&amp;#160;These regulations take effect for large refiners on January 1, 2011 and for small refiners, such as Frontier, on January 1, 2015.&amp;#160;&amp;#160;While not yet estimated, the Company anticipates that potentially material capital expenditures may be necessary to achieve compliance with the new regulation at its Cheyenne Refinery.&amp;#160;&amp;#160;Gasoline manufactured at the El Dorado Refinery typically contains benzene concentrations near the new standard.&amp;#160;&amp;#160;The Company therefore believes that necessary benzene compliance expenditures at the El Dorado Refinery will be substantially less than those at its Cheyenne Refinery.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company owns terminals and pipelines in which various groundwater remediation and monitoring activities are underway and as of December 31, 2010, the Company had a total accrual of $558,000.&amp;#160;&amp;#160;As is the case with companies engaged in similar industries, the Company faces potential exposure from future claims and lawsuits involving environmental matters, including soil and water contamination, air pollution, personal injury and property damage allegedly caused by substances that the Company may have manufactured, handled, used, released or disposed.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&amp;#160;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold"&gt;Cheyenne Refinery.&lt;/font&gt;&amp;#160;&amp;#160;The Company is party to an agreement with the State of Wyoming requiring investigation and interim remediation actions at the Cheyenne Refinery's property that may have been impacted by past operational activities.&amp;#160;&amp;#160;As a result of past and ongoing investigative efforts, capital expenditures and remediation of conditions found to exist have already taken place, including the completion of surface impoundment closures, waste stabilization activities and other site remediation projects.&amp;#160;&amp;#160;As of December 31, 2010 and 2009, the Company had a $4.8 million and $4.6 million accrual, respectively, included on the Consolidated Balance Sheets related to the remediation program.&amp;#160;&amp;#160;The accrual at December 31, 2010 reflects the estimated present value of a $705,000 cost in 2011 and $690,000 in annual costs for 2012 through 2020, assuming a 3% inflation rate, ten more years of the ongoing groundwater remediation program, and discounted at a rate of 7.9%.&amp;#160;&amp;#160;The Company estimates a total cost of $7.8 million for the cleanup and on-going monitoring activities of a waste water treatment pond located on land adjacent to the Cheyenne Refinery which the Company had historically leased from the landowner.&amp;#160;&amp;#160;Cleanup of the waste water pond pursuant to the aforementioned agreement with the State of Wyoming was completed in 2010 with various on-going monitoring for approximately two years.&amp;#160;&amp;#160;As of December 31, 2010, the Company had remaining accruals of $551,000 related to the on-going monitoring activities.&amp;#160;&amp;#160;At December 31, 2009 the Company had a remaining accrual of $5.7 million for this cleanup.&amp;#160;&amp;#160;Depending upon information collected during the on-going monitoring, or by a subsequent administrative order or permit, additional remedial action and costs could be required.&amp;#160;&amp;#160;Pursuant to this agreement, in the fourth quarter of 2009, the Company completed an $11.3 million capital project for the installation of a groundwater boundary control system and associated groundwater recovery wells.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;In October 2009, Frontier Refining Inc. (which owns the Cheyenne Refinery) was served with a Complaint from Region 8 of the EPA alleging unlawful storage of untreated or partially treated refinery wastewater in an on-site surface impoundment and proposing a penalty of $6.8 million in addition to a requirement to clean and close the impoundment at issue.&amp;#160;&amp;#160;Although not admitting violation, the Company has entered into a negotiated settlement agreement with the EPA.&amp;#160;&amp;#160;Based on this agreement, the total estimated settlement expense is $2.7 million.&amp;#160;&amp;#160;This is comprised of a $900,000 penalty (paid in June 2010) and approximately $910,000 for the first phase of the pond cleaning expenses related to injunctive relief with the remaining costs being for legal expenses.&amp;#160;&amp;#160;The $6.8 million accrual, originally recorded in the third quarter of 2009, was adjusted downward in 2010 on the Consolidated Balance Sheets to reflect the new estimate of $2.7 million, and as of December 31, 2010, the Company's remaining accrual was $42,000.&amp;#160;&amp;#160;Initially, the Company expected capital costs for injunctive relief related to the removal and repair of the liner would have been incurred after June 1, 2011 and were estimated at approximately $800,000.&amp;#160;&amp;#160;However, after further analysis and review, the Company has decided to close the on-site surface impoundment by third quarter 2011 for an estimated cost of $1.0 million, which was accrued at December 31, 2010.&amp;#160;&amp;#160;An alternative capital project related to storm water overflow is currently under development.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company completed in 2007 the negotiation of a settlement of a Notice of Violation ("NOV") from the Wyoming Department of Environmental Quality ("WDEQ") alleging non-compliance with certain refinery waste management requirements.&amp;#160;&amp;#160;The Company has estimated that the minimum capital cost for required corrective measures will be approximately $4.2 million and is estimated to be completed in early 2011.&amp;#160;&amp;#160;In addition, the Company accrued a total of $2.3 million for additional work related to the corrective measures, which was substantially completed in 2010, with remaining accruals of $23,000 and $1.2 million at December 31, 2010 and 2009, respectively.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;The Company has received a draft wastewater discharge permit from the WDEQ designed to renew the existing permit.&amp;#160;&amp;#160;This draft includes new discharge limits for selenium and chloride in addition to a requirement for more rigorous toxicity testing of the wastewater discharge.&amp;#160;&amp;#160;Costs for compliance with the new limits, which are currently drafted to become effective on January 1, 2013, are currently not estimable.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&amp;#160;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold"&gt;El Dorado Refinery.&lt;/font&gt;&amp;#160;&amp;#160;The El Dorado Refinery is subject to a 1988 consent order with the Kansas Department of Health and Environment ("KDHE").&amp;#160;&amp;#160;Subject to the terms of the purchase and sale agreement for the El Dorado Refinery entered into between the Company and Shell Oil Products US ("Shell"), Shell is responsible for the costs of continued compliance with this order.&amp;#160;&amp;#160;This order, including various subsequent modifications, requires the El Dorado Refinery to continue the implementation of a groundwater management program with oversight provided by the KDHE Bureau of Environmental Remediation.&amp;#160;&amp;#160;More specifically, the El Dorado Refinery must continue to operate the hydrocarbon recovery well systems and containment barriers at the site and conduct sampling from monitoring wells and surface water stations.&amp;#160;&amp;#160;Quarterly and annual reports must also be submitted to the KDHE.&amp;#160;&amp;#160;The order requires that remediation activities continue until KDHE-established groundwater criteria or other criteria agreed to by the KDHE and the Refinery are met.&lt;/font&gt;&lt;/div&gt;&lt;div style="TEXT-INDENT: 0pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="justify"&gt;&amp;#160;&lt;/div&gt;&lt;div style="TEXT-INDENT: 18pt; DISPLAY: block; MARGIN-LEFT: 0pt; MARGIN-RIGHT: 0pt" align="left"&gt;&lt;font style="DISPLAY: inline; FONT-FAMILY: Times New Roman; FONT-SIZE: 10pt"&gt;&lt;font style="DISPLAY: inline; FONT-WEIGHT: bold"&gt;Other Future Environmental Considerations.&amp;#160;&amp;#160;&lt;/font&gt;Recent scientific studies have suggested that emissions of certain gases commonly referred to as "greenhouse gases" and including carbon dioxide and methane, may be contributing to warming of the earth's atmosphere.&amp;#160;&amp;#160;On April 2, 2007, in Massachusetts, et al. v. EPA, the U.S. Supreme Court held that carbon dioxide may be regulated as an "air pollutant" under the federal Clean Air Act and that the EPA must consider whether it is required to regulate greenhouse gas emissions from mobile sources such as cars and trucks.&amp;#160;&amp;#160;On April 17, 2009, the EPA proposed that certain greenhouse gases, including carbon dioxide, present a danger to public health or welfare.&amp;#160;&amp;#160;The proposed "endangerment finding" was promulgated on December 7, 2009, opening the door to direct regulation of such greenhouse gases under the provisions and programs of the existing Clean Air Act.&amp;#160;&amp;#160;Thus, the EPA can impose restrictions on the emission of greenhouse gases even if the U.S. Congress does not adopt new legislation specifically addressing emissions of greenhouse gases.&amp;#160;&amp;#160;In October 2009, the EPA published a final rule requiring large emitters of greenhouse gases and certain industrial sectors to monitor and report their greenhouse gas emissions to the EPA beginning in 2011 for emissions in 2010.&amp;#160;&amp;#160;On November 30, 2010, the EPA published a final rule expanding its existing GHG emission reporting rule to include onshore oil and natural gas production facilities beginning for 2012 for emissions occurring after January 1, 2011.&amp;#160;&amp;#160;In May 2010, the EPA issued a final rule that determines which stationary sources of greenhouse gas emissions need to obtain a construction or operating permit and install the best available control technology for greenhouse gas emissions.&amp;#160;&amp;#160;The regulation did not identify such technologies.&amp;#160;&amp;#160;In response to the endangerment finding, the EPA adopted regulations that require a reduction in emissions of GHGs from motor vehicles and also could trigger permit review for GHG emission from certain stationary sources.&amp;#160;&amp;#160;The EPA has determined that the motor vehicle GHG emission standards triggered Clean Air Act construction and operating permit requirements for stationary sources beginning on January 2, 2011 when the motor vehicle standards took effect.&amp;#160;&amp;#160;Legislation to prohibit or delay EPA regulation of greenhouse gases may be considered by the U. S. Congress later this year.&amp;#160;&amp;#160;In addition, the EPA has stated its intent to propose regulations in 2011 that would require utilities and refineries to limit incremental greenhouse gas emissions resulting from future facility expansions.&amp;#160;&amp;#160;&amp;#160;The Agency further stated their intent to promulgate such regulations in 2012.&amp;#160;&amp;#160;Although it is not possible at this time to predict how legislation or new regulations that may be adopted to address greenhouse gas emissions would impact the Company's business, any such future laws and regulations will most likely result in increased compliance costs or additional operating restrictions, and could have a material adverse effect on the Company's business, financial condition and results of operations, including demand for the refined petroleum products that it produces.&lt;/font&gt;&lt;/div&gt;</NonNumbericText><NonNumericTextHeader>13.Commitments and Contingencies&amp;#160;Lease and Other CommitmentsIn connection with the acquisition of the El Dorado Refinery, the Company entered into an</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>Includes disclosure of commitments and contingencies. 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