1. WRAP Stationary Sources Forum Meeting November 14-15, 2006
BART Update
WRAP Stationary Sources Forum Meeting
November 14-15, 2006

2. BART update Q & A document BART Q & A – Oct. 2005
August 24, 2006 – has additional BART information
Future Q & A’s

3. Exemptions from BART Modeled impact < contribution threshold (∆ dv)
“Model Plant”
SO2 + NOx < 500 TPY (PTE); facility > 50 km from Class I area
SO2 + NOx < 1000 TPY (PTE); facility > 100 km from Class I area
PM can be included with appropriate justification
Permit limits
< 250 TPY of visibility impairing pollutant
Model plant
Modeled impact less than threshold
Limits must be made enforceable
Install latest, greatest controls available

4. IMPROVE Equation Old Equation New Equation
bext = 3((f(rh))[SO4] + 3((f(rh))[NO3] + 4(f’(rh))[OC] + 10[EC] + 1[IP] + 0.6[CM] + brayleigh
New Equation
[bext = 2.2 x fs(RH) x [Small Sulfate] x fL(RH) x [Large Sulfate]
+ 2.4 x fs(RH) x [Small Nitrate] x fL(RH) x [Large Nitrate]
+ 2.8 x {Small Organic Mass] x [Large Organic Mass]
+ 10 x [Elemental Carbon]
+ 1 x [Fine Soil]
+ 1.7 x fss(RH) x [Sea Salt]
+ 0.6 x [Coarse Mass]
+ Rayleigh Scattering (site specific)
x [NO2 (ppb)]
Use either; be consistent calculating natural, current, and future impacts
BART and RP – changing equations & reconciling results
Postprocessing with CALPUFF/CALPOST

5. UARG Settlement Letter and memo of July 19, 2006
International emissions
Do not add to natural background or subtract from current conditions
Explaining and assessing if implementation strategies are achieving RPGs
Nonair quality impacts – no requirement to include collateral benefits of emission reductions in BART determinations
Use 20% best days or annual average natural background

6. Deciview threshold
State establishes the contribution threshold - should be no higher than 0.5 ∆ dv (e.g. ≥ 0.5 => subject to BART, < 0.5 => exempt) per the guidelines
consideration for establishing the threshold should include the number of emission sources affecting the Class I areas at issue, the magnitude of the sources’ impacts, and the location of the sources. (See 70 FR , July 6, 2005.)
Provide explanation in SIP

7. BART determination (five factors)
BART analysis considers:
Cost of compliance (BART and RP)
$/ton; $/dv in addition to but not in place of
Energy and nonair quality impacts (BART and RP)
Existing controls in use at the source
Remaining useful life (BART and RP)
Degree of visibility improvement
No prescription given to weighting

8. Intra-source trading (bubbling)
BART-eligible units - “You should consider allowing sources to ‘‘average’’ emissions across any set of BART-eligible emission units within a fenceline, so long as the emission reductions from each pollutant being controlled for BART would be equal to those reductions that would be obtained by simply controlling each of the BART-eligible units that constitute the BART-eligible source”. (70 FR 39172)
B-E and non-B-E units – permitted under the Trading Rule
Emissions reductions are greater than case-by-case BART
Geographic distribution of emissions is the same