Refineries process crude oil into petroleum products through a combination of distillation and other processes. A single barrel of crude oil produces a varying amount of gasoline, diesel, jet fuel, and other petroleum products depending on the configuration—or complexity—of the refinery and the type of crude oil being refined. This report focuses on the production of finished gasoline. Finished gasoline is primarily defined by three characteristics: blendstock, vapor pressure, and oxygenate content. Blendstock is the designation for the base gasoline produced so that other materials can be blended in to meet various air quality or other local specifications. Vapor pressure, also known as Reid Vapor Pressure (RVP), measures the gasoline’s evaporation characteristics or volatility. Oxygenates are fuel additives, particularly alcohols and ethers, which increase gasoline octane levels and reduce carbon monoxide pollution associated with automobile emissions. The most widely used oxygenate in the United States is ethanol, which may be added to gasoline in varying percentages. Federal regulations specify that no more than 10 percent ethanol can be blended into gasoline. Ethanol is generally blended with gasoline at the terminal or wholesale “rack”—the distribution center between refineries and retail fueling stations. For the purposes of this report, conventional gasoline does not contain special federal, state, or local blendstock, RVP, or oxygenate requirements unless otherwise noted, while “special fuel blends” refer to blends of gasoline that are designed to be cleaner burning and generally contain either a certain blendstock, RVP, or oxygenate requirement to meet federal, state, or local fuel specifications. An example of a gasoline used to meet a state fuel specification is California Air Resources Board (CARB) gasoline, which is designed to reduce harmful exhaust emissions that cause smog and is used exclusively in California. Petroleum product markets are evolving in part as a result of the increasing use of biofuels—fuels derived from plant or animal products— throughout the country. The Energy Policy Act of 2005 generally required that at least 7.5 billion gallons of biofuels be blended into motor vehicle fuels in the United States by 2012. These targets were later amended under the Energy Independence and Security Act of 2007, which increased the volume of biofuels to be blended with gasoline from 9 billion gallons in 2008 to 36 billion gallons in 2022. EPA was charged with implementing the Renewable Fuel Standard (RFS) program and issuing regulations to ensure that the annual volumes of biofuels specified by the legislation are being blended into motor vehicle fuels. In addition, some states require the use of biofuels. For example, in Minnesota all fuel must contain 10 percent ethanol, while a number of other states offer consumers incentives—such as tax credits and rebates—for purchasing ethanol or other biofuels. The steadily increasing use of biofuels in the United States has complicated the production and distribution of gasoline. Biofuels such as ethanol are produced at dedicated biofuel production facilities—not at refineries—and currently cannot be transported by most petroleum product pipelines. Therefore in order for ethanol to be blended with gasoline, it must be shipped to the terminal by truck or rail, where it is then mechanically mixed with gasoline as it is delivered into trucks for shipping to retail. Gasoline with or without biofuels is typically sold as either branded or unbranded. Branded gasoline is that supplied from major refiners and sold at retail stations under these refiner’s trademarks, and often contains special additives. Contracts for branded gasoline tend to be less flexible than contracts for unbranded gasoline but guarantee a more secure supply. Conversely, unbranded gasoline may be supplied by major or independent refiners, but is not sold under a refining company’s trademark. Buyers of unbranded gasoline may or may not have a binding contractual arrangement with a refiner. The supply infrastructure—which includes pipelines and terminals that hold supply inventories—is a critical component of the nation’s petroleum product market in that it facilitates the flow of crude oil and petroleum products from one geographic region to another. Crude oil pipelines connect several large refining centers to crude oil sources, and petroleum product pipelines connect these refineries to population centers all over the country. Thus, a disruption in one geographic region can affect the supply and prices in another geographic region. To help mitigate the effects of potential supply disruptions caused by refinery outages or sudden increases in demand and to facilitate smooth supply operations, refiners, distributors, and marketers of petroleum products maintain inventories of crude oil and petroleum products. Inventories represent the most accessible and readily available source of supply in the event of a production shortfall, such as one caused by a refinery outage, or increase in demand. In October 2008, we reported that unplanned and planned refinery outages across the United States did not show discernible trends in the frequency or location of outages from 2002 through 2007, with the exception of impacts beginning in 2005 related to Hurricanes Katrina and Rita. During that study, however, we found that EIA does not collect information on refinery outages directly and thus the information it collects on its monthly refinery survey and uses to indirectly estimate outages has a number of limitations. Specifically, EIA’s method of using EIA-810 data to estimate outages cannot distinguish between planned and unplanned outages, which could have different impacts on petroleum product prices for consumers. Also, as we reported, because the monthly refinery survey data are monthly aggregate data, major outages that straddle the end of one month and the beginning of the next may be difficult to identify and the observable effects of those outages could be diluted. We further reported that the exact date and length of an outage may be difficult to determine from EIA’s monthly refinery survey data, making it difficult to use the data to determine whether a specific outage had a significant effect on the production capacity for some petroleum products as well as market prices. Several U.S. agencies have jurisdiction over and monitor the U.S. refining and supply infrastructure industries and petroleum product markets. Within the Department of Energy (DOE), the Energy Information Administration (EIA) collects and analyzes data, including supply, consumption, and prices of crude oil and petroleum products; inventory levels; refining capacity and utilization rates; and some petroleum product movements into and within the United States. Much of the data that the agency collects is obtained by surveys under EIA’s Petroleum Supply Reporting System (PSRS). The PSRS is comprised of 16 data collection surveys and includes, among others, weekly and monthly surveys of refiners, terminals, and pipelines. The purpose of the PSRS is to collect and disseminate basic and detailed data to meet EIA’s responsibilities and energy data users’ needs for credible, reliable, and timely information on U.S. petroleum product supply. EIA generally updates its PSRS surveys every 3 years and has issued such updates in 2003, 2006, and 2009. EIA also conducts analyses in support of DOE’s mission and in response to Congressional inquiries. For example, EIA recently conducted its semiannual forecast of planned refinery outage effects. EIA evaluates a wide range of trends and issues that could have implications for U.S. petroleum product trends and markets, and each year issues a publication known as the Annual Energy Outlook. The Environmental Protection Agency (EPA), among other things, develops and enforces regulations that implement environmental laws that aim to control the discharge of pollutants into the environment by refiners and other industries. The EPA, with the concurrence of DOE, can grant waivers on fuel requirements that allow petroleum product markets to be more easily re-supplied should an “extreme and unusual” situation—such as a problem with distribution of supply to a particular region, a natural disaster, or refinery equipment failure—occur. In addition, EPA oversees the Reformulated Gasoline (RFG) program. This program was developed in response to a requirement in the Clean Air Act that cities with the most severe smog pollution use reformulated gasoline—gasoline blended to burn cleaner and reduce smog-forming and toxic pollutants in the air—to reduce emissions. EPA is also responsible for implementing and issuing regulations to ensure that gasoline sold in the United States contains a minimum volume of biofuels, such as ethanol or biodiesel, and its reports, according to EPA officials, are geared toward collecting data on fuel quality which is enforced at the refinery. Under EPA’s Renewable Fuel Standard (RFS) program, refiners, importers, and blenders are required to use a minimum volume of biofuels each year, determined as a percentage of the total volume of fuel the company produces, blends, or imports. Entities that are unwilling or unable to meet this percentage standard may purchase biofuel credits from other obligated parties in order to satisfy the requirement. EPA monitors RFS program compliance and has the authority to waive the standard if it determines that specified biofuel volumes would cause severe harm to the economy or the environment in a particular region, state, or the country or that there is an inadequate domestic supply. The Department of Transportation’s (DOT) Pipeline and Hazardous Materials Safety Administration focuses on pipeline safety and establishes standards for transmission and distribution systems for crude oil and petroleum product pipeline. Among other things, it oversees pipelines’ design, maintenance, and operating procedures to maintain the safe, efficient, and reliable delivery of petroleum products. The Federal Energy Regulatory Commission (FERC) monitors energy markets and regulates rates and practices of oil pipeline companies engaged in interstate transportation of natural gas, oil and electricity. It establishes and enforces the rates, known as “tariffs,” for transporting petroleum and petroleum products by pipeline.