Community Air Quality Monitoring in Seward, AK
Heidi Zimmer, M.S., Alaska Community Action on Toxics
Mark Chernaik, Science for Citizens
Denny Larson, Global Community Monitor
Russ Maddox, Resurrection Bay Conservation Alliance
Pamela Miller, Alaska Community Action on Toxics
Steven G. Gilbert, PhD, DABT, Institute of Neurotoxicology and Neurological Disorders
Bretwood Higman, PhD, Ground Truth Trekking
Alan H. Lockwood, MD, FAAN., Physicians for Social Responsibility
Michael Riordan, PhD, Physicist and Author
Additional assistance from:
Volunteers in Seward, AK from Resurrection Bay Conservation Alliance
Staff of Alaska Community Action on Toxics and Global Community Monitor
This project was supported by the Alaska Conservation Foundation and the Alaska Chapter of the Sierra Club.
Residents of Seward, Alaska, have expressed concern for years about possible adverse health outcomes from coal dust blowing from the local coal export facility. These residents are concerned that the airborne particulate matter may pose a health threat, particularly to the elderly, children, and people with asthma and other chronic illnesses. The Alaska Railroad and Usibelli Coal Mine (the coal facility operators) have consistently dismissed these complaints and asserted that facility upgrades in 2007 resolved any past issues with fugitive coal dust. The facility operators also point to other potential sources of airborne particulate matter, such as glacier silt, and claim that coal is an insignificant contributor to the particulates in the air.
To address these concerns, citizen volunteers in Seward, Alaska conducted a year-long air quality monitoring project with assistance and training from Global Community Monitor (GCM), Alaska Community Action on Toxics (ACAT), and Resurrection Bay Conservation Alliance (RBCA). The goal of the project was to measure how much of the dust blowing around town is coal from the stockpiles and coal loading facility, and to analyze the potential toxicity of this coal dust. Monitoring consisted of placing two portable particulate monitors developed by the Lane County Air Pollution District and the US EPA at selected locations around Seward and Lowell Point. These devices collected all particulate matter in the air for a 24-hour period, and the filters were then analyzed for PM10, PM2.5, metals, crystalline silica, or carbon content.
The data indicate that coal makes up the majority of the dust captured in the air monitors, which demonstrates that the Seward Coal Loading Facility is a major contributor to airborne dust in Seward. Photos document coal dust coating a boat harbor utility meter and used oil collection center in the Small Boat Harbor. Concentrations of PM10 on some days exceeded the World Health Organization’s recommended thresholds for impairing respiratory and cardiovascular health. Crystalline silica and elemental carbon exceeded levels associated with health risks on a few occasions as well. We recommend further monitoring of the populated areas adjacent to and downwind of the coal loading facility to obtain a more robust data set that would inform mitigation measures. These measures should include the best available technology to limit coal dust emissions from the facility and protect the health of Seward residents and visitors to the community.
Numerous studies link exposure to airborne particulates (particularly PM2.5, particulate matter smaller than 2.5 μm in diameter) with diabetes, asthma, pulmonary disease, cancer, stroke, heart disease, and cognitive disorders such as dementia.1,2 Recent science shows that particulate matter can cause significant harm even at doses below regulatory standards. Researchers comparing the effects of air pollution on lung cancer and cardiovascular mortality reported that cardiovascular risk was evident starting at the lowest dose measured.3 Children are particularly vulnerable to airborne particulate matter due to their smaller size, greater activity, and because their lungs and immune systems are still developing.1,2 Exacerbated asthma is a common complaint in communities suffering from air pollution, and has been a particular concern of Seward parents.
In Seward, where Alaska coal is loaded onto ships bound for Japan, South Korea, and Chile, the coal loading facility has been emitting coal dust, directly affecting the quality of life and health for some in the Seward community. Residents observe that coal dust is blowing from storage piles and the export facility into nearby neighborhoods, schools, homes and boats. These residents are concerned that the airborne particulate matter may pose a health threat, particularly to the elderly, children, and people with asthma.4 The Alaska Railroad and Usibelli Coal Mine (the coal facility operators) dismiss these complaints and assert that facility upgrades in 2007 resolved past issues with fugitive coal dust.5 The facility operators also point to other potential sources of airborne particulate matter, such as glacial silt, and claim that coal is an insignificant contributor to the grit in the air.
Seward Coal Loading Facility
The Seward Coal Loading Facility (SCLF) is the southern terminus of the Alaska Railroad. It is located adjacent to the cruise ship terminal, the Seward Small Boat Harbor, and a number of homes and businesses. The facility receives up to five trains per week of coal from the Usibelli Coal Mine near Healy and unloads this coal onto stockpiles. The uncovered coal stockpiles contain up to 95,000 tons of coal. The facility also loads coal from the stockpile onto large coal ships (with capacities of 45,000 to 75,000 tons) bound for Asian coal markets.6 In 2007 and 2008, the Alaska Department of Environmental Conservation (DEC) cited the Alaska Railroad for air quality violations after numerous complaints from Seward residents about blowing coal dust. Three consultants hired by the Alaska Railroad recommended extensive dust control measures such as limiting the stockpile height to 20 feet, ceasing operations in winds over 20 mph, installing mist or water spray systems, and suspending operations during winter months when temperatures are too cold to operate water-based systems. One consultant measured significant coal dust accumulation inside a nearby Alaska Vocational Technical College (AVTEC) campus building and recommended installing HEPA filters in the building to protect the building users.7 Another key recommendation was to upgrade and put to use the existing baghouse systems that had been installed in 1983 and never used.8,9 These recommendations were largely ignored by the SCLF and the Alaska Railroad which made minimal upgrades to the equipment only partially mitigating the fugitive dust problem. Complaints from residents have continued.10
A History of Community Concern
This is not the first air quality monitoring effort to address the SCLF coal dust issue in the 25 years that the facility has operated. At the request of concerned citizens and the City of Seward, the DEC conducted ambient air quality monitoring for PM10 from January 2011 through May 2012. (PM10 refers to particulate matter (PM) consisting of particles that are less than 10 micrometers in diameter—thinner than a human hair.) The DEC protocol included measurements of PM10 concentration in the air every six days, regardless of wind or other weather conditions. The average of these measurements is assumed to represent the conditions on all other days. The DEC found PM10 concentrations averaging 11µg/m3 (11 micrograms of PM10 per cubic meter of air), with the highest single-day measurement of 54 µg/m3. These measurements are well below the Environmental Protection Agency (EPA) National Ambient Air Quality Standard (NAAQS) of 150 µg/m3, so DEC concluded that Seward has good air quality11 and declined to investigate further into the source or the composition of the dust in the air.
The DEC’s conclusion failed to reassure some Seward residents.12 They pointed out the variable and extreme weather patterns and wanted to know what they are exposed to on windy days when they could see, smell, taste and feel clouds of dark-colored particles. Ambient air quality measurements assess the overall long-term air quality of a region, but are not designed to identify spikes in pollution levels such as variable output from point sources or changes in wind speed. The DEC study measured only PM10, and not PM2.5 (particles smaller than 2.5 micrometers in diameter), and not the elemental composition of the particles. Smaller particulates, the PM2.5, pose more of a health hazard than the PM10 size, because the smaller particles penetrate deeper into the lungs, and some can even be small enough to move directly into the blood stream from the lungs, or pass from the nasal passages into the brain via the olfactory nerve.13 Coal is known to contain toxic heavy metals, such as arsenic, mercury and selenium that are linked to cancer and neurological disorders.1, 14 Silica is another naturally-occurring component of coal; some coals contain a crystalline silica (quartz) content of greater than 5% w/w.15 Inhalation exposure to relatively low concentrations of crystalline silica significantly increases the likelihood of serious pulmonary diseases.16
Citizen Air Quality Monitoring Project
Ongoing community concern about coal dust spurred a citizen air quality monitoring project that collected air quality samples from February 2012 through April 2013. Volunteers from the community carried out the sampling, with assistance and training from Global Community Monitor (GCM), Alaska Community Action on Toxics (ACAT), and Resurrection Bay Conservation Alliance (RBCA). The goal of this project was to measure how much of the dust in the air of the community of Seward is coal dust from the stockpiles and loading facility, and to analyze the dust’s potential toxicity. This study complements the information provided by the DEC ambient PM10 monitoring by measuring smaller particles (PM2.5), and analyzing the particles for carbon content (to indicate coal), toxic metals, and silica.
The aim of the study was to answer these questions:
1) Is the particulate matter in the air a health hazard, particularly on windy days?
2) What proportion of the particulate matter is attributable to the coal loading facility?