Out in Front: State and Federal Regulation of Air Pollution Emissions from Oil and Gas Production Activities in the Western United States

As oil and gas development increases in western states, states are responding at different speeds to protect human health and the environment. Colorado and Wyoming are recognized as having taken relatively early action to regulate air pollution emissions from oil and gas development, with Wyoming adopting its first sector-specific requirements in 1999. In contrast, New Mexico and Utah have been relatively slow to act. Furthermore, the U.S. Environmental Protection Agency did not adopt emissions standards for most oil and gas production activities until 2012, when it relied on Colorado and Wyoming as proving grounds for control technology. The regulatory history in these four western states shows that concern about ozone nonattainment was an important driver for control requirements in Colorado and Wyoming. These two states also have a history of relatively stringent pre-construction permitting requirements for small sources. In some areas, National Environmental Policy Act requirements for cumulative impact assessment drove adoption of tighter controls to mitigate impacts of growth. Moving forward, federal emissions standards will even out control requirements for new sources across the western states. However, control efforts that go beyond the 2012 federal standards will likely be needed in ozone nonattainment areas in western Wyoming, northeastern Utah, Colorado’s Front Range, and in Indian Country. Further efforts will also be needed to address greenhouse gas emissions including methane

Assessment of source contributions to seasonal vegetative exposure to ozone in the U.S.

W126 is a cumulative ozone exposure index based on sigmoidally weighted daytime ozone concentrations used to evaluate the impacts of ozone on vegetation. We quantify W126 in the U.S. in the absence of North American anthropogenic emissions (North American background or “NAB”) using three regional or global chemical transport models for May–July 2010. All models overestimate W126 in the eastern U.S. due to a persistent bias in daytime ozone, while the models are relatively unbiased in California and the Intermountain West. Substantial difference in the magnitude and spatial and temporal variability of the estimates of W126 NAB between models supports the need for a multimodel approach. While the average NAB contribution to daytime ozone in the Intermountain West is 64–78%, the average W126 NAB is only 9–27% of current levels, owing to the weight given to high O3 concentrations in W126. Based on a three-model mean, NAB explains ~30% of the daily variability in the W126 daily index in the Intermountain West. Adjoint sensitivity analysis shows that nationwide W126 is influenced most by NOx emissions from anthropogenic (58% of the total sensitivity) and natural (25%) sources followed by nonmethane volatile organic compounds (10%) and CO (7%). Most of the influence of anthropogenic NOx comes from the U.S. (80%), followed by Canada (9%), Mexico (4%), and China (3%). Thus, long-range transport of pollution has a relatively small impact on W126 in the U.S., and domestic emissions control should be effective for reducing W126 levels

The short-term association of selected components of fine particulate matter and mortality in the Denver Aerosol Sources and Health (DASH) study

Background: Associations of short-term exposure to fine particulate matter (PM2.5) with daily mortality may be due to specific PM2.5&nbsp;chemical components. Daily concentrations of PM2.5&nbsp;components were measured over five years in Denver to investigate whether specific PM2.5&nbsp;components are associated with daily mortality. Methods: Daily counts of total and cause-specific deaths were obtained for the 5-county Denver metropolitan region from 2003 through 2007. Daily 24-hour concentrations of PM2.5, elemental carbon (EC), organic carbon (OC), sulfate and nitrate were measured at a central residential monitoring site. Using generalized additive models, we estimated relative risks (RRs) of daily death counts for daily PM2.5&nbsp;and four PM2.5&nbsp;component concentrations at single and distributed lags between the current and three previous days, while controlling for longer-term time trend and meteorology. Results: RR of total non-accidental mortality for an inter-quartile increase of 4.55 &mu;g/m3&nbsp;in PM2.5&nbsp;distributed over 4 days was 1.012 (95 % confidence interval: 0.999, 1.025); RRs for EC and OC were larger (1.024 [1.005, 1.043] and 1.020 [1.000, 1.040] for 0.33 and 1.67 &mu;g/m3 increases, respectively) than those for sulfate and nitrate. We generally did not observe associations with cardiovascular and respiratory mortality except for associations with ischemic heart disease mortality at lags 3 and 0&ndash;3 depending on the component. In addition, there were associations with cancer mortality, particularly for EC and OC, possibly reflecting advanced deaths of a frail population. Conclusions: PM2.5 components possibly from combustion-related sources are more strongly associated with daily mortality than are secondary inorganic aerosols.</p

Climate Change and Western Public Lands: a Survey of U.S. Federal Land Managers on the Status of Adaptation Efforts

Climate change and its associated consequences pose an increasing risk to public lands in the western United States. High-level mandates currently require federal agencies to begin planning for adaptation, but the extent to which these mandates have resulted in policies being implemented that affect on the ground practices is unclear. To examine the status of adaptation efforts, we conducted an original survey and semistructured interviews with land managers from the four major federal land management agencies in the U.S. states of Colorado, Utah, and Wyoming. The survey was designed to examine current planning for adaptation on public lands and how it differs from prior planning, the major challenges facing land managers in this region, the major barriers preventing managers from planning for adaptation, and the major hurdles associated with implementing adaptation plans. Our results show that some adaptation planning is currently taking place, but that few adaptation projects have made it to the implementation phase. Overall, respondents considered lack of information at relevant scales, budget constraints, lack of specific agency direction, and lack of useful information to be the most common barriers to adaption planning. Budget constraints, lack of perceived importance to the public, and lack of public awareness or demand to take action were reported to be the biggest hurdles to implementation of adaptation projects. Agencies showed differing levels of adaptation activity, and reported different barriers to adaptation and hurdles to implementation. Reasons for the differences and implications for future research and policy are discussed