Commitments and Contingencies . Environmental Matters Due to the nature of our business, certain of our subsidiaries' operations are subject to numerous existing and proposed laws and governmental regulations designed to protect the environment, particularly regarding plant wastes and emissions and solid waste disposal. Our consolidated environmental liabilities were $36 million and $37 million as of March 31, 2019 and December 31, 2018 , respectively, primarily within our Metals and Energy segments and which are included in accrued expenses and other liabilities in our condensed consolidated balance sheets. We do not believe that environmental matters will have a material adverse impact on our consolidated results of operations and financial condition. On August 21, 2018, CVR Refining received a letter from the United States Department of Justice (the DOJ) on behalf of the Environmental Protection Agency (the "EPA") and Kansas Department of Health and Environment (KDHE) alleging violations of the Clean Air Act and a 2012 Consent Decree between CVR Refining, the United States (on behalf of the EPA) and KDHE at CVR Energy's Coffeyville refinery. In September 2018, CVR Refining executed a tolling agreement with the DOJ and KDHE extending time for negotiation regarding the agencies allegations through March 2019, which was extended in March 2019 through November 30, 2019. At this time CVR Energy cannot reasonably estimate the potential penalties, costs, fines or other expenditures that may result from this matter or any subsequent enforcement or litigation relating thereto and, therefore, CVR Energy cannot determine if the ultimate outcome of this matter will have a material impact on its financial position, results of operations or cash flows. Renewable Fuel Standards CVR Refining is subject to the Renewable Fuel Standard ("RFS") of the EPA which requires refiners to either blend "renewable fuels" in with their transportation fuels or purchase renewable fuel credits, known as renewable identification numbers (RINs), in lieu of blending. CVR Refining is not able to blend the substantial majority of its transportation fuels and has to purchase RINs on the open market, as well as waiver credits for cellulosic biofuels from the EPA, in order to comply with the RFS. For the three months ended March 31, 2019 and 2018, our Energy segment recognized expense of $13 million and a benefit of $23 million , respectively, which is included in cost of goods sold in the condensed consolidated statements of operations. Our Energy segment's cost to comply with the RFS includes the purchased cost of RINs, the impact of recognizing CVR Refining's uncommitted biofuel blending obligation at fair value based on market prices at each reporting date and is reduced by the valuation change of RINs purchases in excess of CVR Refining's RFS obligation as of the reporting date. Litigation From time to time, we and our subsidiaries are involved in various lawsuits arising in the normal course of business. We do not believe that such normal routine litigation will have a material effect on our financial condition or results of operations. Energy CVR Energy, CVR Refining and its general partner, Icahn Enterprises and certain other affiliates and individuals have each been named in nine lawsuits filed in the Court of Chancery of the State of Delaware by purported former unitholders of CVR Refining, on behalf of themselves and an alleged class of similarly situated unitholders (the Call Option Lawsuits). The Call Option Lawsuits primarily allege breach of contract, tortious interference and breach of the implied covenant of good faith and fair dealing and seek monetary damages and attorneys fees, among other remedies, relating to CVR Energy's exercise of the call option under the CVR Refining Amended and Restated Agreement of Limited Partnership assigned to it by CVR Refinings general partner. The Call Option Lawsuits are in the earliest stages of litigation. CVR Energy believes the Call Option Lawsuits are without merit and intends to vigorously defend against them. Other Matters Pension Obligations Mr. Icahn, through certain affiliates, owns 100% of Icahn Enterprises GP and approximately 91.7% of Icahn Enterprises' outstanding depositary units as of March 31, 2019 . Applicable pension and tax laws make each member of a controlled group of entities, generally defined as entities in which there is at least an 80% common ownership interest, jointly and severally liable for certain pension plan obligations of any member of the controlled group. These pension obligations include ongoing contributions to fund the plan, as well as liability for any unfunded liabilities that may exist at the time the plan is terminated. In addition, the failure to pay these pension obligations when due may result in the creation of liens in favor of the pension plan or the Pension Benefit Guaranty Corporation (the "PBGC") against the assets of each member of the controlled group. As a result of the more than 80% ownership interest in us by Mr. Icahns affiliates, we and our subsidiaries are subject to the pension liabilities of entities in which Mr. Icahn has a direct or indirect ownership interest of at least 80%, which includes the liabilities of pension plans sponsored by ACF. All the minimum funding requirements of the Internal Revenue Code, as amended, and the Employee Retirement Income Security Act of 1974, as amended, for the ACF plans have been met as of March 31, 2019 . If the plans were voluntarily terminated, they would be underfunded by approximately $61 million as of March 31, 2019 . These results are based on the most recent information provided by the plans actuary. These liabilities could increase or decrease, depending on a number of factors, including future changes in benefits, investment returns, and the assumptions used to calculate the liability. As members of the controlled group, we would be liable for any failure of ACF to make ongoing pension contributions or to pay the unfunded liabilities upon a termination of the ACF pension plans. In addition, other entities now or in the future within the controlled group in which we are included may have pension plan obligations that are, or may become, underfunded and we would be liable for any failure of such entities to make ongoing pension contributions or to pay the unfunded liabilities upon termination of such plans. The current underfunded status of the ACF pension plans requires them to notify the PBGC of certain reportable events, such as if we cease to be a member of the ACF controlled group, or if we make certain extraordinary dividends or stock redemptions. The obligation to report could cause us to seek to delay or reconsider the occurrence of such reportable events. Starfire Holding Corporation ("Starfire"), which is 99.6% owned by Mr. Icahn, has undertaken to indemnify us and our subsidiaries from losses resulting from any imposition of certain pension funding or termination liabilities that may be imposed on us and our subsidiaries or our assets as a result of being a member of the Icahn controlled group, including ACF. The Starfire indemnity provides, among other things, that so long as such contingent liabilities exist and could be imposed on us, Starfire will not make any distributions to its stockholders that would reduce its net worth to below $250 million . Nonetheless, Starfire may not be able to fund its indemnification obligations to us. Other The U.S. Attorneys office for the Southern District of New York contacted Icahn Enterprises L.P. in September 2017 seeking production of information pertaining to our and Mr. Icahns activities relating to the Renewable Fuels Standard and Mr. Icahns former role as an advisor to the President. We cooperated with the request and provided information in response to the subpoena. The U.S. Attorneys office for the Southern District of New York contacted Icahn Enterprises L.P. in June 2018 seeking production of information pertaining to trading in Manitowoc Company, Inc. securities. We cooperated with the request and provided documents in response to the subpoena. The U.S. Attorneys office has not made any claims or allegations against us or Mr. Icahn with respect to either of the foregoing inquiries. We maintain a strong compliance program and, while no assurances can be made, we do not believe these inquiries will have a material impact on our business, financial condition, results of operations or cash flows.