EPA WATCH Eight-hour ozone standards proposed To provide greater protection for atrisk individuals, the Office of Air Quality Planning and Standards proposed in a staff paper that EPA, in its review of National Ambient Air Quality Standards for ozone levels, set a new standard of an average of 0.07-0.09 parts per million (ppm) measured over an eight-hour period with one instance exceeding that standard allowed per year. This would be a significantly more stringent standard than the current 0.12 ppm measured over an hour, says David McKee of the Air Quality Standards and Strategies Division, though at this stage it is only a recommendation. Based on a review of all information EPA has gathered to date, the current standard is inadequate to meet the human health concerns of those groups that are at greatest risk, the staff paper suggests. McKee listed these groups as primarily moderately active children who play outdoors and outdoor workers in summer. EPA must decide whether to propose the new level as the NAAQS standard by mid-1996, with a final decision expected about a year later. The proposed standard appears to be slightly more stringent, though the 0.09 ppm average at the upper end would not meet the criteria for at-risk populations, says Ron White of the American Lung Association. "EPA needs to be looking at the bottom end of the range." He said his association was heartened by EPA's belief that the current standard needs to be strengthened. Depending on what is officially proposed as the NAAQS standard, the American Petroleum Institute (API) may prefer die new eight-hour standard, according to an API spokesperson, who added that there have been "difficulties" in the current hourly measurement system. He said the organization has not had the opportunity to review the staff paper, but using an eight-hour averaging method would likely overcome a "lack of ro-
bustness" in the current standard. Because meteorology affects the ozone levels, the one-hour standard makes the possibility of a meteorological effect "bumping you into non-attainment" more likely, he said.
Banking in wetlands EPA, spearheading a five-agency effort with the Army Corps of Engineers, published proposed guidance that would further govern the practice of wedands mitigation banking {Federal Register, March 6). Mitigation banking entails restoring disrupted wetlands or creating new ones of equal or greater area to compensate for wetlands losses elsewhere. The guidance would allow for restoring or creating—restoration is preferred—wetlands in advance as credit for future development that would have a negative impact on an existing wedands, according to Thomas Kelsh of the Office of Wedands, Oceans, and Watersheds. Establishing mitigation banking enables EPA to ensure that the wetlands restoration is successful before the credit is given and that wedands are restored prior to the disruption of other wedands, he said. The guidance will open mitigation banking to public and private organizations and will allow credits to be sold to other developers. Already about a dozen "private entrepreneurial banks" are in operation, Kelsh said. Regulators would prefer to confine mitigation banking to within a watershed mainly as compensation for habitat and flood controls, he added. The guidance will establish the methods and instruments required for setting up and operating a bank as well as criteria for using it. The guidance also clarifies what type of wetlands can be used in a mitigation, so that numerous pond habitats are not too frequently used to mitigate for a loss to a forested swamp. Also, the guidance discusses mitigation ratios, especially compensation for temporal losses that occur during the long time needed to re-
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store a wetlands. The other agencies involved in drafting the guidance are the Department of Agriculture's Natural Resources Conservation Service, the Interior Department's Fish and Wildlife Service, and the National Oceanic and Atmospheric Administration. With the comment period ending in mid-April, EPA hopes to be able produce a final version by this summer.
EPA methods and ion trap mass spectrometry Can ion trap mass spectrometers be used for all EPA methods? Speaking in March at the Pittcon meeting in New Orleans, William Budde, director of the Chemistry Research Division of the Environmental Monitoring Systems Laboratory in Cincinnati, OH, said that his survey of all officially promulgated EPA mass spectrometry (MS) methods found that "there is no restriction on the design of the mass spectrometer." The ion trap is a newer mass spectrometer design that leads to more compact, lighter instruments; several manufacturers are promoting these systems for environmental measurements. Instead of mass spectrometer design, Budde cited performance requirements such as scan speed, gas chromatography (GC) interface, and the use of either decafluorotriphenylphosphine (DFTPP) or 4-bromofluorobenzene (BFB) as standards as the key issues for EPA's MS methods. DFTPP and BFB ensure that the GC/MS system is measuring correct masses and natural U C isotope ratios, and the standards check the spectrometer's resolution. Adding a practical note, Budde said that currently problems develop when ion traps are used for environmental analyses of dioxins. These analyses require mass resolutions of 10,000 or greater for selective ion monitoring. "In principle ion traps can do it, but in reality no commercial manufacturer is ready to offer an instrument with that resolution," Budde pointed out.
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