Category: Pollutants

Inversions

Under normal atmospheric conditions, air is warmer near the ground and colder at higher altitudes. In a temperature inversion, the situation “inverts,” and cold air at the surface gets trapped under a layer of warmer air. During the winter, snow-covered valley floors reflect rather absorb heat, preventing the normal vertical mixing of warm and cold …

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Particulate Matter 2.5 (PM2.5) Overview

PM2.5 particulates are fine, inhalable particles or droplets with a diameter of 2.5 microns or smaller. These fine particulates, which are about 30 times smaller than the width of a human hair, can travel deeply into the lungs and cause both short-term and long-term health effects. While larger PM10 particulates can compromise respiratory and cardiac …

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PM2.5 Moderate Area State Implementation Plans (SIPs) (2009-2014)

Jump to: Background Nonattainment State Implementation Process Area Designations and SIP Call Moderate SIP Goals and Deadlines Stakeholder Process Subpart 1 Moderate Area SIPs Subpart 1 SIP Control Measures Court Decision Subpart 4 Moderate Area SIPs Logan PM2.5 SIP Salt Lake PM2.5 SIP Provo PM2.5 SIP Emission Limits and Operating Practices for Large Stationary Sources …

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Area Designations:
PM2.5 State Implementation Plan Development

Nonattainment designation is determined by the EPA when an area or areas within a state persistently exceed the National Ambient Air Quality Standards. The EPA has designated "nonattainment areas" for Particulate Matter having an aerodynamic diameter of 2.5 microns (μm) or less (PM2.5). The three EPA designated areas include: Provo, Utah Logan, Utah and Franklin …

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Public Comment:
PM2.5 State Implementation Plan Development

Public comments are a critical part of the decision making process. The Department of Environmental Quality and its divisions and boards are committed to using the public notice and comment process to improve the decisions they make. The most effective comments: Request actions the agency has legal authority to make. Provide new information the agency …

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Area Source Rules:
PM2.5Moderate SIP

The following rules were adopted as part of the overall emissions control strategy for the PM2.5 SIPs. The rules themselves can be accessed online. R307-202 Emission Standard: General Burning R307-204 Emission Standard: Smoke Management R307-208 Outdoor Wood Boilers R307-221 Emission Standard: Emission Controls for Existing Municipal Solid Waste Landfills R307-302 Solid Fuel Burning Devices R307-303 …

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PM2.5 Air Trend Plots

PM2.5 data has been collected at most monitoring stations since 2000. Like PM10, maximum values also tend to occur during wintertime inversions. Also like PM10, trends are somewhat difficult to evaluate because weather plays such a large role in the data collected from year-to-year. This is why the standard is evaluated over a three year …

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Serious Area PM2.5 State Implementation Plan (SIP) Development (2017-2019)

The Serious PM2.5 SIP Development is very much an iterative process. The technical foundation of any SIP involves numerous emissions inventories, air quality modeling assumptions, potential emission controls, and ever-fluctuating design values recorded throughout the air monitoring network. The PM2.5 Implementation Rule is very prescriptive about how these numbers must fit together to comprise an …

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Control Strategies:
Serious Area PM2.5 SIP

Disclaimer The Serious PM2.5 SIP Development is very much an iterative process. The technical foundation of any SIP involves numerous emissions inventories, air quality modeling assumptions, potential emission controls, and ever-fluctuating design values recorded throughout the air monitoring network. The PM2.5 Implementation Rule is very prescriptive about how these numbers must fit together to comprise …

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Public Participation:
Serious Area PM2.5 SIP

Jump to: Public Comment Period (November 1 – November 30, 2018) Public Comment Period (October 1-October 31, 2018) Public Comment Period (July 1 – August 15) Public Comment Period (May 16 – June 16) Menu Current Air Quality Rule and Plan Changes EPA recently reclassified two of Utah’s three PM2.5 Nonattainment areas from Moderate to …

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Technical Analysis:
Serious Area PM2.5 SIP

Jump to: Background Emissions Inventories Posted Inventories Modeling Disclaimer The Serious PM2.5 SIP Development is very much an iterative process. The technical foundation of any SIP involves numerous emissions inventories, air quality modeling assumptions, potential emission controls, and ever-fluctuating design values recorded throughout the air monitoring network. The PM2.5 Implementation Rule is very prescriptive about …

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Particulate Matter 10 (PM10) Overview

Jump to: Air Quality Standards Area Designations Air Trend Plots Particulate matter (PM) is a complex mixture of small, solid particles and liquid droplets in the air. PM10 is particulate matter that is 10 microns (μm) or less in diameter. It is a mixture of materials that can include soot, metals, salt, and dust. Major …

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PM10 State Implementation Plans and Maintenance Plans

Nonattainment Areas In 1987, the EPA set new air-quality standards for PM10 of 150µg/m3 over a 24-hour period and an average of 50 µg/m3 annually. Utah was initially unable to meet the 24-hour standard and was required to prepare State Implementation Plans for Salt Lake and Utah County. Ogden City was designated nonattainment on September …

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Ecological Study:
Nutrients in Utah’s Waters

The Utah Division of Water Quality conducted a study in 2010 to evaluate the ecological impacts of nutrient additions from POTWs on the State’s streams and rivers. The study was conducted on receiving waters above and below the discharges of eight mechanical treatment plants and one lagoon system. The Division studied these waters above and …

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