----------------- --------- ----------------- -------- -------- --------------- ------------- -----------------------------------------------------------------
  **SUMMARY OF                                                                                  
  MEASUREMENT SITES                                                                             
  FOR PARTICULATE                                                                               
  MATTER (PM2.5)                                                                                
  SPECIATION^0^**                                                                               

  **Numbers of                                                                                  
  Measurement Sites                                                                             
  for Each PM                                                                                   
  Species**                                                                                     

  **Network**       **Total   **Major Ions      **OC**   **EC**   **Trace         **Sampling    **Location of Information and/or Data**
                    Number of (SO4,NO3,NH4)**                     Elements^9^**   Frequency**   
                    Sites**                                                                     

  **State / Local /                                                                             
  Federal                                                                                       
  Networks**                                                                                    

  NCore^1^          --        --                --       --       --                            <http://www.epa.gov/ttn/amtic/monstratdoc.html>

  SLAMS -- EPA^2,5^ \~150     207               207      207      207                           <http://www.epa.gov/ttn/airs/airsaqs/aqsweb/aqswebhome.htm>

  STN \--EPA^3,5^   54        54                54       54       54              3-day         <http://www.epa.gov/ttn/airs/airsaqs/aqsweb/aqswebhome.htm>
                                                                                  schedule      
                                                                                  24-hr average 

  IMPROVE \-- Class 110       110               110      110      110                           <http://vista.cira.colostate.edu/improve/>
  I^8^                                                                                          

  IMPROVE \--       67        67                67       67       67                            <http://vista.cira.colostate.edu/improve/>
  Protocol^4,8^                                                                                 

  CASTNet^6^        80+       88                                                  weekly        <http://www.epa.gov/castnet/>
                                                                                  average       

  **Industry                                                                                    
  Networks**                                                                                    

  ARIES/SEARCH^7^   8         8                 8        8        8                             <http://www.atmospheric-research.com/studies/SEARCH/index.html>
  ----------------- --------- ----------------- -------- -------- --------------- ------------- -----------------------------------------------------------------

0\. Methods Discussion (Rich).

1\. NCore is a network proposed to replace NAMS, as a component of
SLAMS; NAMS are designated as national trends sites. To avoid double
counting, the NCore sites are incorporated in STN and SLAMS totals.

2\. Based on EPA samplers; does not include IMPROVE protocol.

3\. Based in National Park Class 1 areas; also includes 2 sites.

4\. Includes \~10 CASTNET located sites, and other RPO and EPA \-- SLAMS
funded sites.

5\. Counts of sites for which selected PM species are measured are based
on a search of air quality measurements in AQS that was made on
04/19/06. Monitor type, pollutant or \"parameter\" code, and the last
sampling date for a given monitoring site were the primary search
factors considered. Last sampling dates encompassed 2004 to the present.
Parameter codes unique to each pollutant were chosen. The following
monitor types were selected for inclusion with the indicated types of
networks:

> SLAMS \-- EPA network includes: SLAMS speciation types
>
> STN \-- EPA network includes: Trends speciation, PAMS, and unofficial
> PAMS monitoring types.

6\. Counts of sites for which selected PM species are measured are based
on a \"Quick Report\" for 2004 from the CASTNet website made on
04/19/06. Measurements at CASTNet sites utilize an open inlet (all
particle sizes) and Filter Pack providing weekly integrated averages for
sulfate and total nitrate (particles and nitric acid).

7\. Counts of sites for which selected PM species are measured are based
on information from the SEARCH website taken on 04/19/06.

8\. IMPROVE does not report NH4 due to concerns regarding NH3 offgases
from filters.

9\. Elements include Na to Pb on the periodic table measured through
typical XRF scans and other analysis techniques. Major differences
between IMPROVE and EPA networks are analysis respectively of 24 versus
48 elements; differences in elements considered are currently being
reassessed since many are rarely detected. A listing of elements is
provided in the following table:

  ------------- ----------------- --------------------- -------------------
  **XRF         **Species Name**  **XRF Species         **XRF Species
  Species**                       Reported in IMPROVE   Reported in STN
                                  Databases**           Databases**

  Na            Sodium            X                     X

  Mg            Magnesium         X                     X

  Al            Aluminum          X                     X

  Si            Silicon           X                     X

  P             Phosphorus        X                     X

  S             Sulfur            X                     X

  Cl            Chlorine          X                     X

  K             Potassium         X                     X

  Ca            Calcium           X                     X

  Sc            Scandium                                X

  Ti            Titanium          X                     X

  V             Vanadium          X                     X

  Cr            Chromium          X                     X

  Mn            Manganese         X                     X

  Fe            Iron              X                     X

  Co            Cobalt                                  X

  Ni            Nickel            X                     X

  Cu            Copper            X                     X

  Zn            Zinc              X                     X

  Ga            Gallium                                 X

  As            Arsenic           X                     X

  Se            Selenium          X                     X

  Br            Bromine           X                     X

  Rb            Rubidium          X                     X

  Sr            Strontium         X                     X

  Y             Yttrium                                 X

  Zr            Zirconium         X                     X

  Nb            Niobium                                 X

  Mo            Molybdenum                              X

  Ag            Silver                                  X

  Cd            Cadmium                                 X

  In            Indium                                  X

  Sn            Tin                                     X

  Sb            Antimony                                X

  Cs            Cesium                                  X

  Ba            Barium                                  X

  La            Lanthanum                               X

  Hf            Hafnium                                 X

  Ta            Tantalum                                X

  W             Tungsten                                X

  Ir            Iridium                                 X

  Au            Gold                                    X

  Hg            Mercury                                 X

  Pb            Lead              X                     X

  Ce            Cerium                                  X

  Sm            Samarium                                X

  Eu            Europium                                X

  Tb            Terbium                                 X
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