Task 3: HAPs Emission Inventory

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Task 3 HAPs Emission Inventory

• Step 1 Compile screening-level inventory from
  existing databases.
• Area Visit
• Salt River PM10 SIP Inventory
• Maricopa County Point Source Files
• Maricopa Association of Governments Ozone
  Precursors Inventory (?)
• Speciation Profiles based on EPA or Equivalent
  Standards or Engineering Judgment
• Step 2 Evaluate the screening-level inventory
  for information gaps.

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Task 3 HAPs Emission Inventory

• Step 3 Address information gaps.
• Compile available information and estimate
  emissions.
• Prepare recommendations for further research.

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Summary of PM10 Emissions

• Source Salt River PM10 Inventory
• Needed Revisions
• Estimate annual emissions for some source
  categories ().
• Address missing source categories that are
  important for toxics (e.g., lawn/garden, off-road
  diesel, charbroiling, etc.).

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Summary of VOC Emissions

• Source Maricopa Countys records of major point
  source emissions of VOCs
• Additional information needs to be acquired or
  developed, including gridded emissions for area,
  non-road mobile, and on-road mobile sources.

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Emissions Estimates for HAPs
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Example Plot for Chromium
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Example Plot for Chromium

• Map features
• Emissions for the southern half of the domain
  will be addressed during the later stages of the
  inventory development project, when we begin
  addressing information gaps.
• Point source emissions range up to 103 grams per
  day. The most significant point source plotted
  is National Gypsum Company.
• Non-point source emissions range up to 6 grams
  per day per grid cell.
• Wind erosion from alluvial channels and disturbed
  lands appears to be the largest non-point source.
  However, it is important to note that the map
  represents a windy day, or worst-case conditions
  for this source.

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Next Steps

• Identify and list source categories in need of
  more attention.
• Review aerial photography for expanded domain
  (when it becomes available).
• Use EPA Guidance to identify important sources of
  Priority HAPs, highly toxic HAPs, and/or urban
  HAPs.
• Cross-reference lists of source types with
  existing or anticipated emissions sources.
• Identify and evaluate techniques to estimate and
  spatially allocate emissions.
• Recommend prioritization scheme.

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Tentative Recommendations

• More detail and specific proposals will be
  included with the interim memorandum.
• Recommendations for significant sources
• Furniture finishing plant
• Review facility methods for estimating VOC
  emissions.
• Develop facility-specific VOC and HAPs profiles.
• On-road mobile sources
• Develop toxics inventory by applying MOBILE6 and
  local inputs. (Much of this work is already
  done.)
• Fugitive dust
• Reprise earlier methods for the purpose of
  estimating annual emissions rather than
  day-specific emissions.

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Tentative Recommendations

• Determine how best to address non-point sources
  of ozone precursors.
• Two options
• Acquire the MAGs model-ready inventory.
• Prepare a model-ready inventory from scratch.
• Address sources that are unlikely to be included
  in screening-level inventories, but are likely to
  be important sources of HAPs (e.g., lawn/garden,
  off-road diesel, charbroiling, etc.).
• Investigate potential sources of HAPs observed
  through the air monitoring program.