Chesapeake Bay Program Atmospheric Deposition and by myf10644

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									 Chesapeake Bay Program:
Atmospheric Deposition and
   It’s Impacts on Loads

          Jeffrey S. Sweeney
         University of Maryland
    Chesapeake Bay Program Office
     jsweeney@chesapeakebay.net
             410-267-9844


           January 4, 2007
                         Atmospheric Deposition and the
                       Role of the Chesapeake Bay Program
•       Need to use best-available science to support environmental decisions
        regarding emission controls.
•       Need involvement of jurisdictions, federal stakeholders, scientific
        community to direct emission-deposition-load assessments.
    o      Need to better engage the air and water communities.
    o      Complexity of the assessments is related to complexity of the ecosystem.
•       Need to portray cause-and-effect relationships among emissions,
        deposition, land, and loads to highlight issues – so management decisions
        are better informed.
•       May need to track the status and expectations of individual jurisdictional
        air programs – to inform and, possibly, coordinate efforts.
•       Need peer-review body to oversee work.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
QUESTION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       Historic
    o       Projected
•       More important question to inform management decisions – than “How
        much of the load is attributable to deposition?”
                                             Historic and Projected Atmospheric Deposition to the
                                                          Chesapeake Bay Watershed
                               396                   394              391
                         400


                         350
                                              Monitored                                            Modeled
                                                                                               CAIR+CAMR+BART
                         300
                                                                                                      275
(million lbs. TN/year)




                         250
                                                                                                                                         229


                         200


                         150


                         100


                          50


                           0
                               1990

                                      1992

                                              1994

                                                     1996

                                                            1998

                                                                   2000

                                                                          2002

                                                                                 2004

                                                                                        2006

                                                                                               2008

                                                                                                      2010

                                                                                                             2012

                                                                                                                    2014

                                                                                                                           2016

                                                                                                                                  2018

                                                                                                                                         2020
                                             Historic and Projected Atmospheric Deposition to the
                                                          Chesapeake Bay Watershed
                               396                   394              391
                         400


                         350
                                              Monitored                                            Modeled
                                                                                               CAIR+CAMR+BART
                         300
                                                                                                      275
(million lbs. TN/year)




                         250
                                                                                                                                         229


                         200
                                                                                      Models-3/Community Multi-scale Air Quality
                                                                                               (CMAQ) Modeling System)
                         150                                                     • Provides estimates of N deposition resulting from
                                                                                 changes in precursor emissions from utility, mobile,
                                                                                 and industrial sources due to management actions
                         100                                                                            or growth.
                                                                                      • Adjusts deposition determined by wet-fall
                                                                                    concentration model and precipitation volumes
                          50
                                                                                   • Predicts the influence of source loads from one
                                 NADP/NTN + Atmospheric Integrated                       region on deposition in other regions.
                                Research Monitoring Network (AirMoN)              • Provides estimates of wet:dry for NO3- and NH4-.
                           0
                               1990

                                      1992

                                              1994

                                                     1996

                                                            1998

                                                                   2000

                                                                          2002

                                                                                 2004

                                                                                        2006

                                                                                               2008

                                                                                                      2010

                                                                                                             2012

                                                                                                                    2014

                                                                                                                           2016

                                                                                                                                  2018

                                                                                                                                         2020
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
QUESTION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       Historic
    o       Projected
                                                            Historic Atmospheric Deposition to the
                                                                 Chesapeake Bay Watershed
                               396                      394                391
                         400


                         350
                                                  Monitored


                         300
                                                                                                              275
                                                                                              Nitrate ion wet deposition, 2004
(million lbs. TN/year)




                         250
                                                                                                                                                      229


                         200


                         150

                                              Mean annual (1985-2001)
                         100


                          50    Apply daily NH4+ and NO3- concentration model
                               results to daily precipitation from a high resolution
                               hourly precipitation model developed by the USGS
                           0    for river modeling segment in the CB watershed.
                               1990

                                       1992

                                                 1994

                                                         1996

                                                                 1998

                                                                        2000

                                                                               2002

                                                                                       2004

                                                                                              2006

                                                                                                      2008

                                                                                                              2010

                                                                                                                      2012

                                                                                                                                 2014

                                                                                                                                        2016

                                                                                                                                               2018

                                                                                                                                                      2020
             Before and After Implementation of
     Title IV of the Clean Air Act Amendments of 1990

          Mean Annual Wet Deposition of Nitrate

Before: 1983-1994                        After: 1995-2004
1999 NOx Facility Emissions




                     • Range: 0 to 1135 tons/yr
                     • Resolution: 1km
                     • From EPA AirData facility criteria
                     emissions reports
  Allocation of 1999 NOx Emissions
from Transportation-Related Sources




                         • Range: 0 to 1425 tons/yr
                         • Resolution: 1km
                         • Derived from EPA AirData county-
                         specific criteria emissions reports
                         and NLCD classifications
Allocation of 1999 Ammonia Emissions
       from Agricultural Sources




                         • Range: 0 to 925 tons/yr
                         • Resolution: 1km
                         • Derived from EPA AirData county-
                         specific criteria emissions reports
                         and NLCD classifications
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
QUESTION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       Historic
    o       Projected
                                                        Projected Atmospheric Deposition to the
                                                              Chesapeake Bay Watershed
                               396                    394               391
                         400


                         350                                                                         Modeled
                                                     CMAQ Scenarios                              CAIR+CAMR+BART
                                  2010 and 2020 Clean Air Interstate Rule (CAIR) +
                         300       Clean Air Mercury Rule (CAMR) + Best Available
                                      Retrofit Technology (BART) Partial Listing:                       275
(million lbs. TN/year)




                                    • Projected EGU emissions under emissions caps
                         250                    • NOx SIP Call as remanded                                                                 229
                                                 • Tier 2 tailpipe standards
                                  • Heavy Duty Diesel Engines (HDDE) rule standards
                         200          • Land-based Non-road Diesel Engines (LNDE)
                                • Large Spark Ignition and Recreational Vehicle rules
                                • Reasonably Available Control Techniques (RACT) for
                         150                NOx in ozone non-attainment areas
                                          • Air-bourn particulate matter (PM2.5)

                                         2020 Allocation of State Responsibility
                         100          Each watershed state & states as a single set

                                               2020 Sector Responsibility
                                                    EGU & industry
                          50                            Mobile

                                              2030 Long-Range Projection
                                               2020 Limit Of Technology
                           0
                               1990

                                       1992

                                              1994

                                                       1996

                                                              1998

                                                                     2000

                                                                            2002

                                                                                   2004

                                                                                          2006

                                                                                                 2008

                                                                                                        2010

                                                                                                               2012

                                                                                                                      2014

                                                                                                                             2016

                                                                                                                                    2018

                                                                                                                                           2020
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
QUESTION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       Historic
    o       Projected
                                         Historic and Projected Atmospheric Deposition to the
                                        Chesapeake Bay Watershed and the Response in Loads

                                         Atmospheric Deposition                                  Chesapeake Bay Loads
                         450                                                               Goal is nitrogen load reduction from all
                               395.8
                                                                                           air programs from 1996 = 15 million lbs.
                                                     393.9                 390.8
                         400                                                              NOx SIP call, etc. = 7 million lb. reduction
                                                                                         Other air programs, i.e., CAIR = 8 million lbs.
                         350
(million lbs. TN/year)




                         300
                                                                                                 274.7

                         250                                                                                           229.4

                         200              189.9                 189.7                 189.3
                                                                                                            175.3                 169.9

                         150

                         100

                          50

                           0
                               Cap Load Allocation   Cap Load Allocation   Cap Load Allocation   Cap Load Allocation   Cap Load Allocation
                               w/ 1990 Deposition    w/ 1996 Deposition    w/ 2001 Deposition    w/ Projected 2010     w/ Projected 2020
                                                                                                     Deposition            Deposition
                     The Impacts of Emission Controls on
                Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       7 million lb. load reduction goal is built into jurisdictional Tributary
            Strategies.
               Comparison is made between baseline and 1990 Clean Air Act projected
                benefits – as assessed during the time of allocating the nutrient cap loads.
                  Primarily Tier II tail pipe standards on light duty vehicles.
                  Utility emissions with Title IV (Acid Rain Program) fully implemented.
                  20-state NOx SIP call reductions at 0.15 lbs/MMbtu during the May to
                   September ozone season only.
    o       8 million lb. load reduction goal is EPA’s commitment beyond what’s
            built into jurisdictional Tributary Strategies.
               Comparison is made between 1990 Clean Air Act projected benefits and
                projection from CAIR + CAMR + BART.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       The benefits in load reductions to the Chesapeake Bay – from
            reductions in emissions and deposition – are dependent on the land
            cover the air flux falls on.
    o       For most Bay Program air impact assessments, this land condition is
            held constant so only changes in loads to the Bay due to changes in
            deposition are quantified.
              Scenarios are run with the same watershed conditions for landuses,
               manure and chemical fertilizer applications, nonpoint source BMPs, point
               sources, septic, etc.
                  The baseline watershed condition is a scenario where each jurisdictional portion
                   of the major tributaries hits their cap load allocations for nutrients and sediment
                   exactly.
              The baseline landuse is not the strategies’ condition exactly.
                  Strategies were developed at different times over several years.
                  It is not prudent to do the entire suite of air impact scenarios every time a
                   jurisdictional plan is finalized or revised.
                  There would be confusion among stakeholders and decision-makers working
                   with air programs if the deposition-to-load cause-and-effect relationship changed
                   constantly because of landuse changes.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       The benefits in load reductions to the Chesapeake Bay – from
            reductions in emissions and deposition – are dependent on the land
            cover the air flux falls on.
              Forests, on average, retain more than 85% of the nitrogen deposited on
               them from the air.
                  “If all of the 5.5 million acres of the forest that both maximizes water
                   quality but is vulnerable to development is lost, an additional 29
                   million lbs. of nitrogen annually will reach the Bay.” (Forest Sector
                   Issue Paper, Expansion and Retention of Forested Area, Chesapeake
                   Bay Program Implementation Committee, 10/19/06)
              Impervious surfaces don’t retain nutrients but channel the load directly to
               adjacent land or water.
               Sources of Nitrogen Inputs to the Watershed and
                        Loads to the Chesapeake Bay
QUESTION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Source perspective
    o      Less important question to inform management decisions – than “How
           do emission controls impact deposition to the watershed and loads to
           the Chesapeake Bay?”
                                     Sources of Nitrogen Inputs to the Watershed and
                                              Loads to the Chesapeake Bay
                               Atmospheric Deposition                   Chemical Fertilizers
                               Manure                                   Municipal & Industrial Wastewater
                               Septic
        1,500
                                      15
                                      63


        1,200
                                     461
                                                           Nitrogen Attenuation
(million lbs. TN/year)




                                                             Uptake by vegetation
                         900                                     • Soil storage
                                                               • Denitrification

                                     489                           28% of nitrogen load from atmospheric deposition
                         600                                            Rooted in relative proportion of inputs
                                                                      Does not include deposition to tidal water

                                                                15
                         300                                    63                              12
                                                                68                              57
                                     394                                                        51
                                                                91
                                                                                                74
                                                                103                             76
                           0
                                    Inputs              Load to Local Waters          Load Delivered to Bay
                                                    Sources of Nitrogen Inputs
                                                to the Chesapeake Bay Watershed
                                 Atmospheric Deposition                            Chemical Fertilizers
                                 Manure                                            Municipal & Industrial Wastewater
                                 Septic
                         900
                                              93.7
                                            lbs/acre        • Based on year 2004 estimates from the CBP Phase 4.3 Watershed Model.
                         800                                  • Contributions exclude atmospheric deposition directly to tidal waters.
                                                              • Point source loads reflect measured discharges while nonpoint source
                                                                           loads are based on an average-hydrology year.
                         700

                                               461
(million lbs. TN/year)




                         600

                         500

                         400
                                                                                  32.0
                         300     9.7                                            lbs/acre
                               lbs/acre        307
                         200
                                                                                   182
                                 227                           10.7
                         100
                                                             lbs/acre
                                               86               5                  76                  63                  15
                           0
                                Forest      Agriculture   Non-Tidal Water   Urban/Suburban         Municipal &           Septic
                                                                                                    Industrial
                                                                                                   Wastewater
                                                          Sources of Nitrogen Loads
                                                           to the Chesapeake Bay
                                 Atmospheric Deposition                                Chemical Fertilizers
                                 Manure                                                Municipal & Industrial Wastewater
                                 Septic
                         900
                                                               • Based on year 2004 estimates from the CBP Phase 4.3 Watershed Model.
                         800                                     • Sources of nitrogen loads are rooted in the relative inputs of sources.
                                                                 • Contributions exclude atmospheric deposition directly to tidal waters.
                                                                 • Point source loads reflect measured discharges while nonpoint source
                         700
                                                                              loads are based on an average-hydrology year.
(million lbs. TN/year)




                         600

                         500

                         400                                                                          14.8
                                                                                                    lbs/acre
                         300                                                                     Developed Land


                         200                  11.7
                                 1.7        lbs/acre             8.4                 6.1
                         100
                               lbs/acre        51              lbs/acre            lbs/acre
                                 41            44                  4                  29                   57                 12
                           0                   11                                     20
                                Forest      Agriculture      Non-Tidal Water    Urban/Suburban        Municipal &            Septic
                                                                                                       Industrial
                                                                                                      Wastewater
                                              Sources of Nitrogen Loads
                                               to the Chesapeake Bay

          Sources by Watershed Model                                        Sources with the Break-out for
           Major “Landuse” Category                                            Atmospheric Deposition

                            Septic                                                                Septic
                             5%                                                                    5%
      Municipal &                                                                                          Agriculture - manure
                                                                                                                   19%
       Industrial                                                  Municipal & Industrial
      Wastewater                                                       Wastewater
         21%                                                               21%
                                               Agriculture
                                                  40%


                                                                                                                    Agriculture - chemical
                                                                                                                           fertilizer
                                                                   Urban & Suburban                                          16%
                                                                   Runoff - chemical
Urban & Suburban                                                       fertilizer
                                                                         11%
     Runoff
      18%                                                            Natural - lightning +
                                                                         forest soils                              Agriculture -
         Atmospheric                                                          1%                             Atmospheric Deposition -
       Deposition to Non-                                                                                    livestock & fertilized soil
                                     Forest                                   Atmospheric Deposition -
                                                                                                                     emissions
          Tidal Water                 15%                                      mobile (on-road + non-
                                                                                                                        6%
              1%                                                                 road) + utilities +
                                                                                     industries
                                                                                        21%




                • Based on year 2004 estimates from the Chesapeake Bay Program Phase 4.3 Watershed Model.
    • Sources of nitrogen loads in the break-out chart are rooted in the relative inputs of natural and anthropogenic sources.
                  • Contributions exclude atmospheric deposition directly to tidal waters of the Chesapeake Bay.
     • Point source loads reflect measured discharges while nonpoint source loads are based on an average-hydrology year.
                               Sources of Nitrogen Emissions and Loads
                                        to the Chesapeake Bay
                                                                   Septic
                                                                    5%
                                                                            Agriculture - manure
                                                                                    19%
                                   Municipal & Industrial
                                       Wastewater
                                           21%




                                                                                     Agriculture - chemical
                                                                                            fertilizer
                                Urban & Suburban                                              16%
                                Runoff - chemical
                                    fertilizer
                                      11%
                                    Natural - lightning +
                                        forest soils                                Agriculture -
                                             1%                               Atmospheric Deposition -
                                                                              livestock & fertilized soil
                                               Atmospheric Deposition -
                                                                                      emissions
                                                mobile (on-road + non-
       NOx Emission from Sources                                                         6%                    NH3 Emission from Sources
                                                  road) + utilities +
           in 14 States in the                        industries                                                   in 14 States in the
        Chesapeake Bay Airshed                           21%                                                    Chesapeake Bay Airshed

                                                                                                                                                   area (non-
  mobile (non-                                                                                                                                  agricultural) +
                      area                                                                                                                   utilities + industries
    road)
                      6%                                                                                    mobile (on-road)                 + mobile (non-road)
     16%                                                                                                         10%                                  10%



                                   utilities
                                    27%




mobile (on-
  road)                      industries
  39%                           12%                                                                                            agriculture
                                                                                                                                  80%
                              Sources of Nitrogen Loads
                               to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Loads from All Land Types
              Loads to the Bay, with deposition break-out, are rooted in relative inputs of
               sources to the watershed.
                  Manure
                  Chemical fertilizer
                  Atmospheric deposition of NOx and NH3
    o      Is proportioning method valid – to inform management decisions?
                              Sources of Nitrogen Loads
                               to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      In the Phase 4.3 Watershed Model, it’s assumed there’s a balance of
           organic nitrogen fluxes to/from the land.
              Deposition of organic N = emissions of organic N from the land.
              Assumption yields lower portion attributable to deposition.
              Is this assumption valid?
                               Sources of Nitrogen Loads
                                to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Deposition to All Land Types
              Deposition to all land types is often rooted in the relative emissions of
               sources.
    o      National air models provide sense of how much of NOx and NH3
           emissions can be attributed to various general sources in watershed
           states or states in entire airshed.
              Utilities
              Industry
              On-road mobile
              Non-road mobile
              Area
    o      Assessments at more-detailed source break-outs cannot yet be done
           in-house.
              Specific relations among emissions, deposition, and loads.
              Use of the sophisticated national air models are costly for the Bay
               Program.
                              Sources of Nitrogen Loads
                               to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Sources of nitrogen loads to the Bay by typically-reported “landuse”
           categories versus break-outs for atmospheric deposition, manure, and
           chemical fertilizers.
              Agriculture
                  Cannot simply divide agricultural component into portions attributable
                   to fertilizers (organic and inorganic) and atmospheric deposition.
                  Agriculture is also a source of nitrogen emissions in the airshed and
                   deposition that falls on all watershed lands.
                  Employing a “break-out” of the atmospheric deposition component of
                   loads slightly increases the portion attributable to agriculture.
                       80-85% of the ammonia emissions in states in the Chesapeake Bay airshed
                        are attributable to the agriculture sector – primarily from livestock in
                        houses and holding facilities, but including fertilizers applied to the land.
                       Ammonia deposition represents 1/4 to 1/3 of the total nitrogen deposition
                        to the Chesapeake Bay watershed.
                       Currently, ammonia emission controls in the agricultural sector are part of
                        PA and MD Tributary Strategies.
                               Sources of Nitrogen Loads
                                to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Sources of nitrogen loads to the Bay by typically-reported “landuse”
           categories versus break-outs for atmospheric deposition, manure, and
           chemical fertilizers.
              Urban & Suburban Runoff
                  Contribution is smaller with the deposition break-out.
                  Includes what can be managed at a more-local level, i.e., fertilizer
                   inputs, imperviousness, etc.
                       Could be local controls on mobile, utility, and/or industrial emissions.
                       Runoff is heightened because of imperviousness.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
QUESTION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o       Historic
    o       Projected
Chesapeake Bay Program Reducing Pollution Indicators:
                    Air Pollution




                        Answer two questions:
                  • How is the Bay/Watershed doing?
• What’s being done and are we on track in our efforts to restore the Bay?

                         Provide accountability
                    • Connecting efforts with results

                  Provide guidance for future efforts
 • Intended audience is “interested public” and environmental managers
                                                 Reducing Pollution Environmental Indicator:
                                                                 Air Pollution
                                                                                                                         Modeled
                                                                    Controlling Nitrogen                                Projection
                   100%

                           90%      Goal is nitrogen load reduction from all air programs from 1996 = 15 million lbs.
                                             Projected reduction primarily from NOx SIP Call = 7 million lbs.
                           80%           Projected reduction from other air programs, i.e., CAIR = 8 million lbs.

                           70%
Percent of Goal Achieved




                           60%

                           50%

                           40%

                           30%

                                                                           Monitored/              Monitored/
                           20%
                                                                            Modeled                 Modeled
                                                             Interpolation           Interpolation
                           10%

                           0%
                                 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10
                                             Accounting Begins
                                               Reducing Pollution Environmental Indicator:
                                                               Air Pollution
                                                               Controlling Nitrogen
                   100%

                           90%

                           80%

                           70%
Percent of Goal Achieved




                           60%

                           50%

                           40%

                           30%

                           20%                                            5% of Goal Achieved
                           10%

                           0%
                                 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10
                                           Accounting Begins
                               Reducing Pollution Environmental Indicators:
                             Air Pollution, Agriculture, Urban/Suburban Lands
                           100%



                                                                           Air Nitrogen Pollution                                                     5% of Goal
                           90%

                           80%

                           70%                                                                                                           For reporting purposes, it’s
                                                                                                                                       necessary to account for the air
                           60%

                           50%

                           40%                                                                                                          piece, but is method correct?
                           30%

                           20%

                           10%

                            0%
                                   85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10
                           100%
Percent of Goal Achieved




                                                                 Agriculture Nitrogen Pollution                                                        44% of Goal
                           90%

                           80%

                           70%                                                                                                               Should 2005 include impact
                                                                                                                                               of reduced deposition?
                           60%

                           50%

                           40%

                           30%

                           20%

                           10%

                            0%
                                   85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 00 01 02 03 04 05 06 07 08 09 10

                             0%
                                   85   86   87   88   89   90   91   92   93   94   95   96   97   98   99   00   01   02   03   04   05   06   07   08   09   10
                           -10%



                                                  Urban/Suburban Lands Nitrogen Pollution
                           -20%

                           -30%

                           -40%

                           -50%

                           -60%
                                                                                                                                                      -88% of Goal
                           -70%                                                                                                              Should 2005 include impact
                           -80%
                                                                                                                                               of reduced deposition?
                           -90%

                           -100%
                       Reducing Pollution Environmental Indicators:
                           Current (2004) Restoration Efforts

        How important is urban versus agriculture versus wastewater versus air?


                      Individual Sources                         All Sources
                           Nitrogen                               Nitrogen
100%                                                      100%

 80%                                                      90%

 60%                                                      80%

 40%                                                      70%
            61%
 20%                         44%                          60%

  0%                                                      50%

-20%
         Wastewater       Agriculture   Developed Lands   40%

-40%                                                      30%
                                            -88%
-60%                                                      20%        41%

-80%                                                      10%

-100%                                                      0%
                 The Impacts of Emission Controls on
            Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•   Is it necessary to isolate the air piece from agriculture and
    urban/suburban land and, if so, how?
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       Is it necessary to isolate the air piece from agriculture and
        urban/suburban land and, if so, how?
    o        Keep the air component as part of agricultural and urban/suburban
             lands?
              CAA reductions were built in during the development of Tributary
               Strategies.
              Typically report loads by model landuses – rather than as the more-
               fundamental manure, chemical fertilizers, and atmospheric deposition.
                  Model is calibrated by model landuse “source”, not the more-fundamental
                   sources.
                  “Lands” are managed by states and localities while air emissions are typically,
                   but not entirely, regulated at the federal level (CAA, CAIR, etc.).
                  Emission controls from as distant as Texas, Canada, and the Bahamas can
                   impact the Bay watershed’s deposition.
              But an indicator specifically for air is necessary.
                     The Impacts of Emission Controls on
                Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       Is it necessary to isolate the air piece from agriculture and
        urban/suburban land and, if so, how?
    o        Up until this point, the agriculture and developed sectors are not
             moving closer to their goals much because of reductions in
             atmospheric deposition since deposition is largely unchanged.
              Regulated reductions mostly from the EGUs have been offset by increases
               in emissions from the mobile sector (primarily) and increases in ammonia
               emissions from the agricultural sector (secondarily).
    o      As net reductions in deposition increase through CAIR, as projected,
           need to determine how to best account for this in reporting.
                     The Impacts of Emission Controls on
                Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       Is it necessary to isolate the air piece from agriculture and
        urban/suburban land and, if so, how?
    o        EPA's commitment to an 8 million lb. TN/year load reduction will
             continue, in the near future, to be separated through model analyses
             until, perhaps, a reallocation of the caps.
              EPA goal was agreed to by Bay Program partners to address an “orphan”
               load reduction needed to reach the 175 million lb. TN/year Bay-wide cap.
              Progress toward the EPA air commitment is tracked just as progress
               toward jurisdictional-specific goals.
    o      The ability to do this becomes more difficult as time passes since the
           air programs are considered more part of a comprehensive package
           in, at least, CBP modeling work.
              It will become difficult to definitively separate CAIR from the 1990 Clean
               Air Act as air models (and the national scenarios they assess) are
               upgraded and updated.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       Is it necessary to isolate the air piece from agriculture and
        urban/suburban land and, if so, how?
    o        Completely isolate the air component from agriculture and developed
             lands?
              Issue, in itself, is complicated and goes far beyond a new need to look at
               Tributary Strategies in a different manner with the air component
               separated.
                    The Impacts of Emission Controls on
               Chesapeake Bay Watershed Deposition and Loads
DISCUSSION
•       Is it necessary to isolate the air piece from agriculture and
        urban/suburban land and, if so, how?
    o        Completely isolate the air component from agriculture and developed
             lands?
              Some jurisdiction’s interest in getting “credit” for state emission controls
               that go beyond, for example, ozone-season NOx SIP or Tier II tail pipe
               standards.
                  Reductions in deposition are determined through monitoring program
                   information coming from sites throughout and just beyond the watershed.
                  The root cause and location of the emission controls that yield deposition
                   reductions to the watershed are difficult to ascertain accurately.
                  How do you “credit” emission controls in one watershed state that also benefit
                   other states’ deposition?
                  Who gets “credit” for emission controls outside the Bay watershed boundary that
                   yield deposition reductions to the watershed?
                  Bay Program partners have been considering – and working at answering –
                   these questions for a few years through the development of more-local tools
                   relating emissions, deposition, and loads.
                            Sources of Nitrogen Loads
                             to the Chesapeake Bay
QUESTION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources within the watershed; within the airshed; outside the
        airshed?
    o       Geographic perspective
       Principle Area of NOx Emissions That Contribute
Nitrogen Deposition to the Chesapeake Bay and its Watershed




                                                                  Estimated geographic area
                                                                   where emission sources
                                                                       have the greatest
                                                                    potential in depositing
                                                                   nitrogen to a watershed:
                                                                         MD, VA, PA, NY, WV, DE
                                                                     OH, IN, MI, KY, NC, TN, NJ, SC




                           Watershed boundary
                          NOx Airshed boundary
              Source: Envirocast Weather & Watershed Newsletter
                                          Sources of NOx Emissions
                                           to the Chesapeake Bay

                   NOx Emissions by States in the Chesapeake Bay Airshed

                                                                      PA
                                                                     11%

                                                                                NY
                                                                                9%

                                                                                    VA
                                                                                    6%
                                                                                      MD
               OH, IN, MI, KY,                                                        5%
               NC, TN, NJ, SC                                                      WV
                    63%                                                            5%
                                                                                 DE
                                                                                 1%
                                   • Based on EPA data from the 1999 NEI grown to 2001.
• WV, OH, IN, and KY emissions are dominated by electric power industry while all other states' emissions are dominated by
                                         mobile (on-road and non-road) emissions.
               • Contributions exclude emissions from other states outside the Chesapeake Bay NOx airshed.
                              Sources of Nitrogen Loads
                               to the Chesapeake Bay
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources within the watershed; within the airshed; outside the
        airshed?
    o       National air models provide sense of how much of emissions can be
            attributed geographically to watershed states; states in the entire
            airshed; states outside the airshed – from all sources.
    o       Assessments at finer spatial scales cannot yet be done in-house.
              Specific relations among emissions, deposition, and loads.
              Use of the sophisticated national air models are costly for the Bay
               Program.
                         Atmospheric Deposition and the
                       Role of the Chesapeake Bay Program
•       Need to use best-available science to support environmental decisions
        regarding emission controls.
•       Need involvement of jurisdictions, federal stakeholders, scientific
        community to direct emission-deposition-load assessments.
    o      Need to better engage the air and water communities.
    o      Complexity of the assessments is related to complexity of the ecosystem.
•       Need to portray cause-and-effect relationships among emissions,
        deposition, land, and loads to highlight issues – so management decisions
        are better informed.
•       May need to track the status and expectations of individual jurisdictional
        air programs – to inform and, possibly, coordinate efforts.
    o      Year-round NOx SIP call – not just ozone season
    o      More aggressive light- and heavy-duty tail pipe and diesel standards
    o      “California-type” air quality mandates
    o      “Clean Power” regulations
    o      Etc.
•       Need peer-review body to oversee work.
                         Atmospheric Deposition and the
                       Role of the Chesapeake Bay Program
DISCUSSION
•       How do emission controls impact deposition to the watershed and loads
        to the Chesapeake Bay?
    o      Is the approach for deriving the cause-and-effect relationship between changes
           in deposition and loads reasonable? Can it/should it be improved? How?
    o      How often should updated atmospheric inputs (regression model and CMAQ)
           be provided to the CBPO?
    o      What are the data gaps? What if anything can/should be done about the
           gaps?
    o      How significant are the data uncertainties? Should these uncertainties be
           documented and tracked? Should they guide future deposition research
           priorities?
                         Atmospheric Deposition and the
                       Role of the Chesapeake Bay Program
DISCUSSION
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources?
    o      Is the approach for deriving the atmospheric portion of the load reasonable?
           Can it/should it be improved? How?
    o      Is it necessary to isolate the air piece from agriculture and urban/suburban
           land and, if so, how?
•       How much of the nitrogen load delivered to the Chesapeake Bay is from
        atmospheric sources within the watershed; within the airshed; outside the
        airshed?
                         Atmospheric Deposition and the
                       Role of the Chesapeake Bay Program
DISCUSSION
•       Is the current information communicated well? What could be improved?
•       Do the states/should the states feel confident that they can use this
        information?
•       Should there be documentation by the CBP describing the methodology
        and the uncertainties? Would it help?
•       Should there be a team of experts formed to assist the CBP Office with
        regular reviews?
    o       Nutrient Subcommittee workgroup in CBP structure?
    o       STAC?
    o       Air experts in ad-hoc framework?
              Robin Dennis (NOAA/EPA), John Sherwell (MD DNR), Mark Garrison (ERM),
               Jeff Stehr (UMD), Jeff Grimm (ZedX, Inc., Penn State), Jim Lynch (Penn
               State), Richard Artz (NOAA), Winston Luke (NOAA), Ariel Stein (NOAA),
               Dan Salkovitz (VA DEQ), Mike Kiss (VA DEQ), Kenn Pattison (PA DEP), Ron
               Entringer (NY DEC), Kevin Civerolo (NY DEC), Fred Durham (WV DEP), etc.

								
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