Efforts to Understand and Reduce Regional Haze

In order to reduce regional haze it is necessary to reduce emissions of fine particles (sulfates, nitrates and organic compounds) and those gases that react to form them (e.g. sulfur dioxides, nitrogen dioxides, elemental carbon, organic carbon and dust). It is the fine particles that are so efficient at scattering light and reducing visibility.

In 1999, the U.S. EPA issued the Regional Haze Rule to address poor visibility in federally protected parks and wilderness areas known as Class I areas (see below for more information).This rule requires each state to submit a State Implementation Plan (SIP) for Regional Haze by 2008 and set a target date of 2064 for achieving natural visibility conditions.

In the Regional Haze SIP, states are required to assess key contributors to regional haze formation, develop plans to reduce sources of haze-forming pollutants and submit these plans to EPA. MANE-VU is actively working to reduce regional haze within the region. As part of that process, NESCAUM is working on monitoring networks, data analysis and computer modeling of regional haze. Additionally, MARAMA is working with state agencies on the emissions inventory necessary for the modeling effort and OTC is coordinating the various processes within and among these regional organizations. Use the links provided within this paragraph for updates on work being done by each organization.

Other federal regulations specific to emissions from fossil fuel combustion at power plants and industrial boilers and set National Ambient Air Quality Standards (NAAQS) have and will in the future reduce fine particle pollution, the primary cause of regional haze. These regulations, which must be implemented throughout the country, will help improve visibility and reduce health impacts from fine particles in areas beyond the national parks and wilderness areas. Using the VIEWS trends generator for Acadia National Park we can see a downward trend in regional haze. This graph is the annual five year average of light extinction measurements at Acadia through 2002.

The U.S. EPA and Federal Land Managers at the U.S. Fish and Wildlife Service, U.S. Forest Service and the National Park Service work together to collect air quality data and strive to reduce haze and improve visibility in Class I areas. To further advance the scientific understanding of regional haze and fine particle pollution in the region, states, tribes and other organizations maintain regular permanent monitors measuring various pollution parameters, including fine particles at numerous locations in each state. The DEP runs a number of monitors around the State of Maine which monitor fine and coarse particle levels in the atmosphere.

Information on various monitoring networks which monitor specific compounds within fine particles is provided below. The VIEWS web site contains a wealth of information related to regional haze including monitoring networks. The text below came from web based descriptions of these networks.

IMPROVE -- The Interagency Monitoring of Protected Visual Environments (IMPROVE) program is a cooperative measurement effort governed by a steering committee composed of representatives from Federal and regional-state organizations. The IMPROVE monitoring program was established in 1985 to aid the creation of Federal and State implementation plans for the protection of visibility in Class I areas as stipulated in the 1977 amendments to the Clean Air Act. The objectives of IMPROVE are:

(1) to establish current visibility and aerosol conditions in mandatory class I areas;

(2) to identify chemical species and emission sources responsible for existing man-made visibility impairment;

(3) to document long-term trends for assessing progress towards the national visibility goal;

(4) and with the enactment of the Regional Haze Rule, to provided regional haze monitoring representing all visibility-protected federal class I areas where practical.

IMPROVE has also been a key participant in visibility-related research, including the advancement of monitoring instrumentation, analysis techniques, visibility modeling, policy formulation and source attribution field studies.

IMPROVE sites in Maine are run by various agencies. The are located in: Presque Isle run by the Aroostook Band of MicMacs, Old Town run by The Penobscot tribe, Acadia National Park run by the National Park Service, Moosehorn run by the U.S. Fish & Wildlife Service and the MEDEP runs two sites, one in Bridgeton and the other in Casco Bay.

RAIN -- Regional haze in the MANE-VU domain is driven by a combination of transported aerosols from sources within and outside of the 12-state region. Determining the relative contribution of source regions to visibility degradation is a key task under the haze rule. A new network of sites was deployed in the spring of 2004 to assess this issue. The Rural Aerosol Intensive Network (RAIN) is coordinated by Northeast States Coordinated Air Use Management (NESCAUM), but is a cooperative effort of MANE-VU member state air agencies. RAIN covers the region from western MD (near large sulfur sources in the Ohio river valley) through northwest CT (a “swing” site expected to have impact from a wide range of source locations and types) to Acadia National Park on the Maine coast -- the proverbial “end of the tailpipe” transport receptor site. The initial network consists of these three rural moderate elevation (700 to 2500 feet) sites with detailed PM and visibility-related measurements. The network design includes highly time-resolved (1-2 h) aerosol mass, composition, and optical property measurements to provide enhanced insight into regional aerosol generation and source characterization, factors that drive short-term visibility, and aerosol model performance and evaluation.

A longer term goal of RAIN is to enhance the network with other measurements and sites in future years. A National Weather Service (NWS) ASOS visibility sensor at a RAIN site would allow the large network of existing ASOS data to be “tethered” to visibility measurements we understand well. Strong aerosol acidity, nitric acid, and ammonia are measurements that would be desirable on either an integrated or real-time basis. There are no continuous nitrate measurements in RAIN at this time, since available methods are not yet sufficiently robust, and nitrate is not (yet) a major factor at these sites. Measurements similar to those in RAIN done to the west and south of the MANE-VU domain (Ohio and Virginia for example) would greatly enhance our understanding of the impact of the large sulfur source region in and around the Ohio river valley on regional visibility. It is expected that data from RAIN will be available in real-time to web data resources like VIEWS, FASTNET and AIRNow. RAIN would not be possible without the ongoing support of the participating state air agencies in MD, CT, and ME, as well as the National Park Service and MANE-VU.

STN -- In meeting the requirements to monitor and gather data on the chemical makeup of fine particles, EPA established a Speciation Trends Network (STN). These STN samplers were placed at various national air monitoring stations (NAMS) and State and local air monitoring stations (SLAMS) across the Nation. In 2001 it was anticipated that 54 of these chemical speciation sites would be used to determine, over a period of several years, trends in concentration levels of selected ions, metals, carbon species, and organic compounds in PM2.5. Further breakdown on the location or placement of the trends sites meant that approximately 20 of the monitoring sites were placed at existing Photochemical Assessment Monitoring Stations (PAMS). The placement of the remaining trends sites was coordinated by EPA, the Regional Offices, and the state and local agencies. Locations were primarily in or near larger Metropolitan Statistical Areas (MSAs). The remaining chemical speciation sites were used to enhance the required trends network and to provide information for developing effective State Implementation Plans (SIPs). A quality management plan was drafted to assure data of adequate quality are produced by the 54 trends network sites.

The programmatic objectives of the STN network are:

Annual and seasonal spatial characterization of aerosols;
Air quality trends analysis and tracking the progress of control programs;
Integration of chemical speciation data set with the data collected from the IMPROVE network; and
Development of emission control strategies.

There are no STN sites in Maine. STN and IMPROVE serve essentially the same purpose with IMPROVE being a more rural network and STN being a more urban network.

Class I Areas

Class I areas are national parks exceeding 6,000 acres and wilderness areas and national memorial parks exceeding 5,000 acres and all international parks that were in existence on August 7, 1977. There are 156 Class I areas.

Acadia National Park and Moosehorn National Wildlife Refuge contain Class I areas located within Maine. Class I areas in close proximity to Maine are the Roosevelt Campobello International Park in Canada and the Presidential Dry River Range and the Great Gulf Wilderness Area in New Hampshire.

Acadia National Park

Moosehorn National Wildlife Refuge

Roosevelt Campobello International Park

Presidential Dry River Range and Great Gulf Wilderness Areas

regional Haze

Efforts to Understand and Reduce Regional Haze

Class I Areas