Environmental Protection Agency January 24, 2007 – Federal Register Recent Federal Regulation Documents

EPA is taking direct final action under the Clean Air Act to approve the Miami Sulfur Dioxide Nonattainment Area State Implementation and Maintenance Plan as a revision to the Arizona state implementation plan. The Arizona Department of Environmental Quality developed this plan to maintain the sulfur dioxide national ambient air quality standards in the Miami (Gila County) area. The maintenance plan contains various elements, including contingency provisions that will be implemented if measured ambient concentrations of sulfur dioxide are above certain trigger levels. EPA is also approving the State of Arizona's request for redesignation of the Miami area from nonattainment to attainment for the sulfur dioxide standards. Lastly, EPA is correcting the boundary of the Miami sulfur dioxide nonattainment area to exclude a noncontiguous township that was erroneously included in the description of the area and to fix a transcription error in the listing of one of the other townships. EPA is taking these actions consistent with provisions in the Clean Air Act that obligate the Agency to approve or disapprove submittals of revisions to state implementation plans and requests for redesignation. The intended effect is to redesignate the Miami, Arizona sulfur dioxide nonattainment area to attainment, provide for maintenance of the standard for the ten-year period following redesignation, and correct long-standing errors in the codified description of the area.

This regulation revises a tolerance for combined residues of spiromesifen in or on vegetables, fruiting, group 8 and establishes tolerances for inadvertent or indirect combined residues in or on oat (grain, forage, hay, straw). Interregional Research Project No. 4 (IR- 4) and Bayer CropScience (respectively) requested these tolerances under the Federal Food, Drug, and Cosmetic Act (FFDCA), as amended by the Food Quality Protection Act of 1996 (FQPA).

EPA issued a notice in the Federal Register of November 29, 2006 (71 FR 69112) (FRL-8087-4), concerning the availability of the risk assessments for the fumigant pesticide chloropicrin. This document announces EPA's decision to extend the comment period for 30 days, February 23, 2007.

EPA is announcing a 30-day public comment period for the draft document titled, ``Metabolically-Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates'' (EPA/600/R-06/ 129A). The document was prepared by the National Center for Environmental Assessment (NCEA) within EPA's Office of Research and Development (ORD). In 1997, NCEA published the Exposure Factors Handbook. This comprehensive document provides summaries of available statistical data on various factors that can impact an individual's exposure to environmental contaminants. NCEA maintains the Exposure Factors Handbook and periodically updates the document using current literature and other reliable data made available through research. Many program offices within EPA rely on the data from this handbook to conduct their exposure and risk assessments. One important determinant of a person's exposure to contaminants in air is the ventilation rate, or the volume of air that is inhaled by an individual in a specified time period. Ventilation rates, also known as breathing or inhalation rates, are given in Chapter 5 of the Exposure Factors Handbook. Calculations of the currently recommended ventilation rates were limited by their dependence on a ``ventilatory equivalent,'' which relied on a person's fitness level. This draft report, ``Metabolically-Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates,'' presents a revised approach that calculates ventilation rates directly from an individual's oxygen consumption rate, and applies this method to data provided from more recent sources, such as the 1999-2002 National Health and Nutrition Examination Survey (NHANES) and EPA's Consolidated Human Activity Database (CHAD). In the next edition of the Exposure Factors Handbook, NCEA would like to update the ventilation rate values using this revised approach and the more recently released data. EPA is releasing the draft, ``Metabolically-Derived Human Ventilation Rates: A Revised Approach Based Upon Oxygen Consumption Rates,'' solely for the purpose of pre-dissemination peer review under applicable information quality guidelines. This document has not been formally disseminated by EPA. It does not represent and should not be construed to represent any Agency policy or determination. EPA will consider any public comments submitted in accordance with this notice when revising the document.

In 2001, EPA finalized a new, major program for highway heavy- duty engines. That program, the Clean Diesel Trucks and Buses program, will result in the introduction of advanced emissions control systems such as catalyzed diesel particulate filters (DPF) and catalysts capable of reducing harmful nitrogen oxide (NOX) emissions. This proposal would require that these advanced emissions control systems be monitored for malfunctions via an onboard diagnostic system (OBD), similar to those systems that have been required on passenger cars since the mid-1990s. This proposal would require manufacturers to install OBD systems that monitor the functioning of emission control components and alert the vehicle operator to any detected need for emission related repair. This proposal would also require that manufacturers make available to the service and repair industry information necessary to perform repair and maintenance service on OBD systems and other emission related engine components. Lastly, this proposal would revise certain existing OBD requirements for diesel engines used in heavy-duty vehicles under 14,000 pounds.