ATSDR: Coming Soon to a Power Plant Near You

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ATSDR Coming Soon to a Power Plant Near You?

• Steve Lomax
• Clean Air Strategy Group
• July 19, 2007
• Portland, OR

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What is ATSDR?

• The Agency for Toxic Substances and Disease
  Registry (ATSDR) is a federal agency within the
  U.S. Department of Health and Human Services
  (HHS).
• ATSDR was created by Congress in 1980 under
  CERCLA legislation and its authority was
  broadened under amendments to RCRA and CERCLA.
• ATSDR now has authority to conduct virtually any
  type of exposure or health investigation
  requested by any interested party and to
  recommend interventions to protect public health
  where they are needed.

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Industry Concerns Regarding ATSDR

• ATSDR is substituting its own views of health
  risk from exposure to pollutants that are already
  reviewed and regulated by EPA.
• ATSDRs actions could impact operations at power
  plants and other industries.
• ATSDRs reports could be used as a PR/legal tool
  for environmental and community groups protesting
  new and existing plants.
• Well-intentioned citizens may be misled into
  thinking that power plants pose a health hazard
  when in fact they do not.
• As federal standards are tightened and monitoring
  increases, ATSDR may increasingly determine that
  individual sources adversely impact the public.

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ATSDR ReportsSupport for Toxic Tort Claims?
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ATSDRs Toxicological Profiles

• 1986 Superfund Reauthorization directed ATSDR to
  prepare a list of substances most commonly found
  at facilities on the National Priorities List
  (NPL) and which are determined to pose the most
  significant potential threat to human health due
  to their known or suspected toxicity and
  potential for human exposure at these NPL sites.
• This CERCLA Priority List of Hazardous
  Substances is revised and published on a 2-year
  basis and each substance on the list is a
  candidate to become the subject of a
  toxicological profile prepared by ATSDR.
• In December 1998, ATSDR published a toxicological
  profile for sulfur dioxide (even though it
  appears that sulfur dioxide has never been on the
  list of 275 priority hazardous substances).

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ATSDR SO2 Toxicological Profile (1)

• ATSDR notes that SO2 was identified at 16 of the
  1,467 current of former NPL hazardous waste
  sites.
• ATSDR set a Minimal Risk Level (MRL) of 0.01 ppm
  of SO2 for acute exposure (14 days or less)
• ATSDR states that its MRLs are contaminant
  concentrations in air below which non-cancerous
  harmful effects are unlikely.
• ATSDR set a Lowest Observed Adverse Effect Level
  (LOAEL) of 0.1 ppm.

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ATSDR SO2 Toxicological Profile (2)

• MRL and LOAEL levels based on a single study
  (Sheppard, 1981) of 13 asthmatic volunteers
  exposed to SO2 (100 ppb, 250 ppb, and 500 ppb)
  through a mouthpiece, while exercising on an
  stationary bicycle
• Results
• Two subjects exposed to 0.1ppm SO2 (100 ppb)
  exhibited small but statistically significant
  increases in specific airway resistance, but did
  not exhibit any other adverse or clinically
  significant response
• Study design problems
• No repeat testing to replicate results
• Breathing through a mouthpiece artificially and
  substantially increases SO2 delivery to the lungs

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ATSDR SO2 Toxicological Profile (3)

• Other studies cited by ATSDR in its SO2 profile,
  including more recent studies by Sheppard, do not
  show effects at 100 ppb exposure levels
• Sheppard (1988) later determined that
  concentrations of 400 ppb or greater were needed
  to cause adverse effects.
• Most studies find that SO2 concentrations of 500
  600 ppb are the lowest levels at which adverse
  effects are manifest (in up to 25 of exercising
  asthmatics, and not in others).
• Even at these levels effects are transient,
  similar to effects produced by exercise in clean
  air, did not prevent study subjects from
  completing the exposure protocol, and were
  minimized or prevented by inhaler use

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Federal SO2 Exposure Regulations (1)

• EPA SO2 NAAQS limits
• 0.03 ppm (30 ppb) annual average
• 0.14 ppm (140 ppb) 24-hr average
• 0.5 ppm (500 ppb) 3-hr average (secondary
  standard)
• In 1996 EPA decided not to set a 5-minute
  standard
• Repeated exposures to 5-minute peak SO2 levels
  of 0.60 ppm and above could pose a risk of
  significant health effects for asthmatic
  individuals at elevated ventilation rates in some
  localized situations
• Whether 5-minute peak SO2 concentrations will
  pose a significant public health risk depends
  largely on highly localized factors, (e.g.,
  magnitude of peaks, time of day, activity
  patterns, size of exposed population).
• States are in a far better position than EPA to
  assess the highly localized and site-specific
  factors that determine whether the occurrence of
  such concentrations in a given area poses a
  significant public health risk to the local
  population, and if so, to fashion an appropriate
  remedial response.

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Federal SO2 Exposure Standards (2)

• In 1997 EPA proposed to establish a concern level
  of 0.6 ppm, 5-minute average, and an endangerment
  level of 2.0 ppm, 5-minute average
• Granted States authority to relocate monitors to
  areas of potentially elevated 5-minute
  concentrations and to prevent exceedances of
  concern levels, when appropriate
• EPA is currently reviewing the SO2 NAAQS
• Proposal in Fall 2009 final determination in
  Summer 2010
• For comparison
• OSHA (29 CFR 1910.1000 TABLE Z-1) limits worker
  SO2 exposure to 2 ppm (8-hour average, 5 days per
  week)
• National Institute for Occupational Safety and
  Health (NIOSH), part of the U.S. Department of
  Health and Human Services, recommends that SO2
  exposure levels not exceed 2 ppm (10-hr average)
  and 5 ppm (15-minute average)
• 5 ppm (5000 ppb) is 500 times higher than ATSDR's
  MRL!

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Case 1 City of Austin Plant (1)

• Gas/oil-fired Holly Street Power Plant, Austin,
  TX
• Dec. 3, 1999 Public Health Assessment
• Examined SO2, NO2, particulate matter, EMF,
  cancer risk, noise, fire risk, childrens health
• The information reviewed does not indicate that
  people are currently being exposed to levels of
  contamination that would be expected to cause
  adverse health effects. From analysis of
  available information, we have concluded that the
  Holly Street Power Plant poses no apparent public
  health hazard.
• We estimate that using fuel containing 0.05
  sulfur by weight would result in predicted 1-hour
  and 24-hour SO2 concentrations in the community
  of approximately 200 µg/m3 and 56 µg/m3,
  respectively. These levels are below their
  respective regulatory limits and below the levels
  normally associated with adverse health effects
  in humans. Based on available information, the
  levels of sulfur dioxide produced by the Holly
  Street Power Plant currently poses no apparent
  public health hazard.

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Case 2 AEP Gavin Plant (1)

• EPA Region V requested ATSDR to determine if a
  public health hazard exists for Cheshire, Ohio,
  community members residing near the Gavin Power
  Plant
• EPA provided ATSDR with ambient SO2 and sulfuric
  acid data and community complaints of
  ground-level visible plumes
• ATSDR compared the ambient levels of sulfur
  dioxide and sulfuric acid detected in and around
  Cheshire Village to results from human and animal
  studies to determine if harmful effects might be
  possible for the residents.

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Case 2 AEP Gavin Plant (2)

• ATSDR February 2002 Health Consultation finds
• episodic elevations of sulfur dioxide and
  sulfuric acid levels in and around Cheshire pose
  a public health hazard to some residents,
  particularly residents with asthma.
• Uncertainty exists in deciding whether or not
  people might experience harmful effects
• repeated exposure?
• effects of other pollutants?
• nasal deposition versus lung deposition of
  pollutants?
• sample averaging times?
• meteorology?
• ATSDR recommends
• Reduce ambient peak levels of sulfur dioxide and
  sulfuric acid
• Continue collecting air samples sulfur dioxide
  and sulfuric acid
• Consider conducting air modeling

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Case 3 PSNH Merrimack Station (1)

• In 2001, ATSDR was petitioned by an area resident
  to examine air quality and health effects that
  might be associated with air emissions from the
  coal-fired Merrimack Station Power Plant.
• In 2003, New Hampshire in consultation with ATSDR
  prepared a health consultation that evaluated
  2002-03 air quality data for SO2 and PM10,
  concluding
• Current ambient levels of sulfur dioxide and
  particulate matter are not expected to cause
  adverse health effects, including people with
  asthma and other respiratory conditions.

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Case 3 PSNH Merrimack Station (2)

• A March 2007 public health assessment, of
  2004-2006 air quality data for SO2, ozone, PM2.5,
  cancer incidence and Emergency Department visits
  for respiratory-related diagnoses, concluded
• Ambient air does not present a health hazard to
  the general population.
• Sulfur dioxide levels are not expected to pose a
  public health hazard.
• There are rare occasions when SO2 reaches levels
  at which unusually sensitive asthmatics should
  consider reducing prolonged or heavy exertion
  outdoors in order to avoid possible respiratory
  effects. These SO2 events occur primarily when
  the wind is out of the northwest, the direction
  of Merrimack Station.
• Ozone and PM2.5 events are regional, not expected
  to pose a health hazard.
• Air monitoring data for 15 additional air toxics
  indicate that they do not pose a health hazard to
  any groups.

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Case 3 PSNH Merrimack Station (3)

• Report conclusions (contd)
• Mercury concentrations pose no human health
  hazard through inhalation
• Mercury can be a human health hazard, especially
  to children and pregnant women, through
  consumption of certain species of fish
• No significant elevation in any type of cancer
• Rates of asthma-related emergency department (ED)
  visits for children and the elderly were
  generally lower than expected.
• Report recommendations
• Continue to monitor ambient SO2 data
• Continue inspections and monitoring of Merrimack
  Station
• Continue issuing Air Quality Action Days
• Continue to advise residents to limit their
  exposure to mercury by following the State Fish
  Consumption Advisory

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Case 4 Mirant PRGS (1)

• In January 2006, the City of Alexandria (VA)
  Health Department requested ATSDR to review air
  quality and other environmental data related to
  operations at the Mirant Potomac River Plant.
• April 2006 Mirant begins the use of trona
  injection to reduce emissions of SO2
• January 4, 2007- ATSDR issues letter stating that
  there is significant uncertainty with the
  modeling data and ongoing monitoring for air
  pollutants may show that the air dispersal model
  has overestimated SO2. Because of the
  uncertaintywe cannot determine at this time if a
  public health hazard exists.
• February 13, 2007- City of Alexandria, with ATSDR
  staff approval, issues a press release entitled,
  Federal Health Agency warns of potential health
  hazards from exposure to Mirant power plant.

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Case 4 Mirant PRGS (2)

• Feb. 15, 2007- Mirant issues clarifying press
  release of ATSDR letter.
• Feb-June 2007 - Mirant has numerous discussions
  with ATSDR to attempt to work together to
  understand its Exposure Investigation and related
  protocol and monitoring.
• April 16, 2007 - City of Alexandria submits
  recommendations to ATSDR on placement of monitors
  for ATSDR independent study.
• June 8, 2007 - ATSDR disregards Mirant request to
  monitor during normal operations and after
  planned environmental improvements are made at
  the plant. Without notice, ATSDR begins
  monitoring when the plant is forced to run all
  units under a DOE order. Monitors are placed in
  outdoor and indoor breathing zones to collect
  worst-case samples of 5-min SO2, heavy metals,
  and PM, for 4-6 weeks. Neither the monitoring
  protocol or locations are provided to Mirant.
• June 13, 2007 - After numerous requests, Mirant
  receives a copy of the protocol with the
  monitoring locations excluded.
• Completion of ATDSR monitoring and report are
  pending.

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Some Other ATSDR Utility Industry Investigations

• Bonneville Power Administration Ross Complex,
  hydroelectric distribution station, research
  maintenance facility (September 1994)
• Former NPL site
• Under current conditions poses no apparent
  public health hazard
• In the past, the site might have posed a health
  hazard to workers exposed to surface soils and
  equipment contaminated with PCBs, lead,
  pentachlorophenol, and PAHs. However, there are
  no community-specific health outcome data to
  indicate that the site has had an adverse impact
  on human health.
• Appalachian Power Co. Service Center Glen Lyn
  Plant (May 1994)
• Data are too limited (or are absent) to conclude
  whether improper use or disposal of the
  contaminants PCBs of concern has occurred
• SWEPCO Welsh and Pirkey Power Plants (September
  1998)
• Cooling reservoir discharges from ash ponds
  containing elevated selenium levels, impact on
  fish tissue
• No apparent public health hazard
• Iowa ELP, Fairfield Coal Gasification Plant
  (January 1997)
• Former NPL site
• The Fairfield Coal Gasification site was a
  past public health hazard. People living in the
  area were exposed to site-related contaminants in
  private well water and in the air. Under current
  site conditions, the site poses no apparent
  public health hazard.

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Summary

• Environmental, health and community groups are
  using ATSDR to target individual power plants.
• ATSDR has published reports indicating that some
  plants pose a health hazard to nearby residents,
  even if the plants comply with all federal and
  state environmental regulations.
• ATSDR is examining 5-minute exposures to SO2
  compared to its own level of concern of 0.1 ppm
  (100 ppb) SO2 (6 times lower than EPA's
  short-term concern level), and a minimum risk
  level (MRL) of 0.01 ppm (10 ppb).
• ATSDR reports maintain that adverse health
  effects occur at concentrations as low as 100
  ppb.
• Peak 5-minute concentrations of SO2 near power
  plants may sometimes exceed ATSDR's level of
  concern, and will certainly exceed its MRL.
• ATSDR has misinterpreted the scientific and
  clinical evidence regarding SO2 and has ignored
  EPA's more credible analysis of this substance.