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The document details the use of an ejector—a Venturi-style pipe opening—to mitigate methane emissions during the maintenance of compressors and pipelines. By using high-pressure gas to draw low-pressure gas into a medium-pressure stream, the system avoids atmospheric venting. One partner, Marathon Oil Company, reported saving over 8,000 cubic feet of gas over 55 months using this method. The analysis suggests a single ejector used once a year to drain a 2-mile, 18-inch pipeline can reduce emissions by 700,000 cubic feet per year, with a potential return on investment in less than three years.

The document describes the transition from gas-expansion turbine starters to electric starters for internal combustion engines used in compressors, generators, and pumps within the natural gas sector. It highlights that electric starters eliminate methane venting and leakage, potentially reducing emissions by 23,000 to 600,000 cubic feet per year per unit. The analysis suggests the project can achieve a return on investment in less than three years, depending on capital costs and electricity prices.

The document outlines a technical opportunity to mitigate methane emissions by using pressurized storage for condensate instead of atmospheric storage, which prevents the flashing of methane into the air. Based on data from Burlington Resources, the implementation of four pressurized tanks resulted in total savings of 27,992 thousand cubic feet per year, with methane savings specifically accounting for 7,000 thousand cubic feet per year. The capital cost for installation in 1998 was 37,500 USD, with annual operating costs of 2,500 USD, allowing the methane recovery savings to cover costs within two years.

The document outlines a technical opportunity to reduce methane emissions in natural gas production by installing velocity tubing strings. These strings increase gas flow velocity to remove reservoir liquids without venting gas to the atmosphere. One reported case showed a reduction of 4,680 thousand cubic feet of methane emissions per year per well by eliminating bi-weekly venting. The technology is most applicable to wells with relatively small liquid production and higher reservoir pressure, with a potential payback period of less than three years.

The document outlines a method for reducing methane emissions during compressor shutdowns by redirecting purge gas to a fuel gas system. This practice, reported by the Phillips Enron Gas Pipeline Group, can recover approximately 12,000 cubic feet of gas per shutdown event. For a station with six compressors experiencing 42 shutdowns annually, the estimated savings are 500,000 cubic feet of methane per year. Capital costs for necessary piping and valves are estimated between $900 and $1,600 per compressor, with a projected payback period of less than three years based on a gas price of $3 per thousand cubic feet.

The document outlines a practice reported by Western Gas Resources to control gas hydrate formation in low-pressure gas gathering systems (50-400 psi) by replacing glycol dehydration units with solar-powered methanol injection pumps. This transition eliminated volatile organic compound emissions from dehydration units and reduced methane emissions by an average of 800 thousand cubic feet per site annually. The implementation cost is approximately $2,250 per installation, with a payback period of one year, driven by reduced maintenance, lower operating expenses, and the value of saved gas.

The document describes a practice of extending the replacement interval for internal rotating modules in turbine meters from two years to three years. This change reduces the frequency of pipeline venting during maintenance, thereby lowering methane emissions and labor costs. One partner, Columbia Gas Transmission, reported that this adjustment reduced methane emission rates by approximately one-sixth across hundreds of meters. For a system of 500 8-inch turbine meters, the estimated methane savings are 27 million cubic feet per year.

The document outlines a method to mitigate methane leaks by replacing or supplementing single-use burst plates with secondary relief valves that close automatically once pressure returns to safe levels.

The document outlines a method for removing water from natural gas pipelines using conical separators and in-line heaters instead of traditional glycol dehydration. This approach avoids methane emissions associated with glycol dehydrators. One partner reported saving 1,930 thousand cubic feet of methane by replacing 14 dehydrators, with an estimated annual saving of 130 thousand cubic feet for a specific gas flow volume. The technology is noted for having a fast payback period because capital and operating costs are significantly lower than those of glycol dehydrators.

The document outlines a cost-effective practice for identifying and repairing leaking pressure safety valves to mitigate methane emissions. It specifies that proactive testing using organic vapor analyzers, acoustic leak detectors, or large-volume samplers can prevent significant gas leaks caused by worn seals or contamination. The report provides specific emission reduction data, noting an average emission rate of 57.5 thousand cubic feet per year per valve, with one partner reporting a total methane surplus rate of 853 thousand cubic feet per year. Economic analysis suggests that the practice is most cost-effective when applied to large groups of valves, with a specific example of reducing emissions by 170 thousand cubic feet per year for compressors with three safety valves.

The document outlines a practice where a pig is placed in an isolated pipeline section and pushed by an inert gas to displace natural gas. This process prevents the common practice of depressurizing pipelines by venting gas to the atmosphere during operation or maintenance. One partner reported avoiding 538,000 cubic feet of methane over six such purging operations. The primary driver for this practice is safety rather than methane savings, and it requires pig launching/receiving equipment and a mobile nitrogen supply.

The document outlines the technical application and economic impact of installing downhole separator pumps to mitigate methane emissions from produced water storage tanks.

The document outlines a method for reducing methane emissions in gas production wells by injecting foaming agents (soap) to help lift liquids to the surface, thereby reducing the need for atmospheric purging. It highlights a specific case where emissions were reduced by 2,520 Mcf per year for a single well by changing the purging frequency from bi-weekly to monthly. The primary benefit is the extension of the well's productive life, with capital costs typically ranging from under $1,000 to over $10,000 depending on the installation.

The document outlines a practice for the annual inspection and repair of blowdown valves at compressor stations, which are prone to leaks due to pressure and thermal stress. It provides estimated gas savings, economic evaluations, and methane content assumptions across different natural gas industry sectors.

The document outlines how installing smaller-diameter velocity tubing strings increases gas flow velocity to lift liquids from the reservoir, eliminating the need for frequent atmospheric venting. Based on a report from TotalFinaElf, this practice can save 4,680 Mcf of methane per year per well by removing bi-weekly liquid discharges of 180 Mcf. The technology is most applicable to natural gas wells with higher reservoir pressure and relatively small liquid production, offering a potential return on investment in less than three years.

The document outlines a method for reducing methane emissions by optimizing the operation and maintenance of turbine compressors to avoid frequent engine starts, which typically vent unignited gas to the atmosphere. A reported case by PECO Energy Company demonstrated a reduction in compressor restarts from 9.4 to 1 per year, saving 132 Mcf of methane annually.

The document consists of several appendices. Appendix A lists Class I areas not evaluated by the EPA. Appendix B compares SO2 and NOx reductions under CAIR versus the Best Available Retrofit Technology (BART) standard. Appendix C is a detailed scientific critique of the ARIES study, arguing that utility industry claims using ARIES to downplay the health risks of sulfates are not supported by the study's actual data or broader medical literature. Appendix D lists counties remaining in nonattainment for PM2.5 and ozone. Appendix E contains a statement from the Institute of Clean Air Companies on the achievability of NOx and SO2 limits. Appendices F through L provide detailed modeling data, cost summaries, and emission projections for various policy scenarios (CATF11, 18, 19, 21, 22, 23).

The report details how Hispanic Americans are disproportionately exposed to air pollution, with 71 percent living in counties violating federal air quality standards as of 2002. It identifies specific health risks including asthma, stunted lung growth, and low birth weight, exacerbated by poverty and lack of health insurance. The document also notes risks from mercury contamination in fish and the potential for global warming to induce crop failures and famines. Finally, it argues that the EPA has failed to implement Executive Order 12898 because it has not identified impacted populations or developed criteria for determining disproportionate risk.

The report analyzes the potential health impacts of three policy alternatives to the proposed Clear Skies Act—the Clean Air Planning Act (Carper), the Clean Power Act (Jeffords), and the EPA August 2001 Straw Proposal—focusing on avoidable health effects from fine particulate matter (PM2.5) for the years 2010 and 2020. To ensure direct comparability with U.S. Environmental Protection Agency (EPA) estimates, the study employs the same analytical methods, emissions estimates, air quality forecasting, and health assessment models used by the EPA in its 2003 analysis of the Clear Skies Act.

The report documents that fine particle pollution from U.S. power plants causes nearly 24,000 premature deaths annually, including 2,800 from lung cancer, and 38,200 non-fatal heart attacks. It argues that the Bush administration's 'Clear Skies' proposal is insufficient compared to the Clean Air Act or the more stringent Jeffords bill, which could avoid 22,000 deaths per year. The analysis highlights that elderly populations, children, and communities of color—particularly in the Midwest and Southwest—are disproportionately affected.