Table of Contents may be subject to certain future claims under environmental laws and regulations as a former owner of Four Corners. The extent of such claims, if any, cannot be predicted with certainty. Climate Change.  There has been a wide-ranging policy debate, at the local, state, national and international levels regarding the impact of GHG and possible means for their regulation. Efforts continue to be made in the international community toward the adoption of international treaties or protocols that would address global climate change issues. In April 2016, the U.S. signed the Paris Agreement, which requires countries to review and "represent a progression" in their intended nationally determined contributions, which set GHG emission reduction goals every five years beginning in 2020. In August 2017, the U.S. formally documented to the United Nations its intent to withdraw from the Paris Agreement. The earliest possible effective withdrawal date from the Paris Agreement is November 2020. However, there is no guarantee that the U.S. will not reenter the Paris Agreement or other similar agreements in the future. At the state level, several states have already adopted measures requiring GHG emissions to be reduced within state boundaries. For example, the governor of New Mexico signed an executive order in January 2019 that supports the Paris Agreement and includes a goal of reducing statewide GHG emissions by at least 45% by 2030. The executive order also creates a Climate Change Task Force to evaluate and develop regulatory strategies to reach the 45% reduction goal. The Task Force issued an initial recommendation and status update detailing policy and regulatory strategies in November 2019, and anticipates issuing a second report in the fall of 2020. Although the Company cannot currently determine the effect of potential regulatory strategies that may be suggested by the New Mexico Climate Change Task Force, if implemented, they could be material to the Company's business, reputation, financial condition or results of operations. The federal government has considered, proposed and/or finalized legislation or regulations limiting GHG emissions, including carbon dioxide. In particular, the U.S. Congress has considered legislation to restrict or regulate GHG emissions. In October 2015, the EPA published a rule establishing guidelines for states to regulate carbon dioxide emissions from existing power plants, known as the Clean Power Plan ("CPP"). On August 31, 2018, the EPA published a proposal to replace the CPP called the Affordable Clean Energy ("ACE") rule. The ACE rule was finalized in July 2019. Remaining legal challenges to the CPP were mooted in September 2019, but legal challenges to the ACE rule are ongoing. As adopted, the ACE rule is focused on coal-fired generation and would not impose requirements on our operations. However, at this time the Company cannot determine the impact that the ACE rule and related proposals and legal challenges may have on the Company's financial position, results of operations or cash flows. In addition to legislation and regulations regarding GHGs, there have also been efforts in recent years aimed at the investment community, including investment advisors, sovereign wealth funds, public pension funds, universities and other groups, promoting the divestment of fossil fuel equities as well as to pressure lenders and other financial services companies to limit or curtail activities with companies engaged in the extraction of fossil fuel reserves. If these efforts are successful, our ability to access capital markets may be limited and our stock price may be negatively impacted. Members of the investment community have recently increased their focus on sustainability practices, including practices related to GHGs and climate change, in the natural gas and other industries. Some of our customers have begun to screen their service providers for compliance with sustainability metrics. Additionally, members of the investment community have begun to screen companies such as ours for sustainability performance before investing. Although a significant portion of the Company's generation assets are nuclear or gas-fired, and as a result, the Company believes that its GHG emissions are low relative to electric power companies who rely more on coal-fired generation, current and future legislation and regulation of GHGs; any future related litigation; or pressure from members of the investment community or customers to further improve our sustainability practices could impose significant costs and/or operating restrictions on the Company, reduce demand for the power the Company generates, and/or require the Company to purchase rights to emit GHG, any of which could be material to the Company's business, reputation, financial condition or results of operations. Climate change also has potential physical effects that could be relevant to the Company's business. Climate change could affect the Company's service area by causing higher temperatures, less winter precipitation and less spring runoff, as well as by causing more extreme weather events. Such developments could change the demand for power in the region and could also impact the price or ready availability of water supplies or affect maintenance needs and the reliability of Company equipment. The Company believes that material effects on the Company's business or results of operations may result from the physical consequences of climate change, the regulatory approach to climate change ultimately selected and implemented by governmental authorities, or both. Given the significant uncertainties regarding whether and how these issues will be regulated, as well as the timing and severity of any physical effects of climate change, the Company believes it is not possible to meaningfully quantify the costs of these potential impacts at present. Environmental Litigation and Investigations . Since July 2011, the U.S. Department of Justice, on behalf of the EPA, and APS have been engaged in substantive settlement negotiations in an effort to resolve certain pending matters. The allegations being 6