The Clean Air Act First Clean Air Act passed in 1967: 1970 Amendments established current relationship between states and federal government and required air quality plans Significant revisions in 1977 and Amendments developed because many urban areas continue to violate federal air quality standards Increased emphasis on assessment and control of transported pollution

Criteria Pollutants Identified Six compounds were emitted in quantities sufficient to harm human health and welfare Criteria pollutants reviewed every 5 years and revised if needed Criteria Pollutants – CO, PB, NO2, SO2, O3, PM 10 Primary Pollutants – CO, Pb, NO 2, SO 2,PM 10 Secondary Pollutants – O 3, PM 2.5, Regional Haze

A Quick Primer on How Ground Level Ozone is Formed

Existing 1-Hour Ozone Nonattainment Areas *For the 1-hour ozone standard. Includes Washington bump-up Ozone Transport Region Marginal Nonattainment Severe Nonattainment

Baltimore Region Washington Region Cecil County (Phil. Region) EAC Region (Washington County Only) Kent and QA County – tied to Baltimore NAA EPA’s Recent 8-hr Designation for Maryland (Moderate Nonattainment Areas)

Ozone Days Above the 1-hour Standard Source: MARAMA – 2002 Data

Maryland’s Air Quality Ozone levels in Maryland are very high Fine particulate levels are high Air pollution contributes significantly to Bay pollution Regional haze and air toxics are also significant air pollution problems in Maryland

Air Quality Plans Complexity dependent on many factors – Pollutant formation: Primary vs secondary Local vs regional – Emissions: Predominant source vs many sources – Control measures: Technology vs behavioral changes Technology available vs technology forcing Cost effectiveness and who pays (perception)

Background Heavy-duty diesel engines have significantly lagged behind in the use of aftertreatment-based emission control Significant source of emissions for both NOx (ozone) and Particulate Matter (PM) Contrtibutor to respiratory disease

Health Effects 95% of diesel particulate fall into Pm2.5. Particles this size go deep into the lung Worsens preexisting respiratory conditions such as asthma and allergies In 1998 a California study classified 41 elements in diesel exhaust as toxins

Environmental By 2010 California estimates diesel emissions to: – Account for 39% of all NOx emissions – Account for 94% of all PM emissions

EPA 2007 Rule Adopted January 18,2001 Applicable to all diesel vehicles with a GVWR of 8,501 lbs. And greater Reduced exhaust emission standards Low-sulfur diesel fuel

2007 HDDE Rule Emission Reductions NOx from 2.0 to 0.2 g/bhp-hr (90% reduction) – Phase-in: 50% from 2007 to 2009 and 100% in 2010 Non-Methane Hydrocarbons from 0.5 to 0.14 g/bhp-hr (72% reduction) – Phase-in: 50% from 2007 to 2009 and 100% in 2010 PM from 0.1 to 0.01 g/bhp-hr (90% reduction) – Full implementation in 2007

2007 Rule Fuel Requirements Diesel sulfur levels reduced from 500 ppm to 15ppm (97% reduction) Beginning mid 2006 Full implementation 2007