Operators
for. CONSTELLATI

ON

Balrersfiekl,
CA 93380 Operating Se,vices

661 792-3048 661 792-2812 Fax Delivery Address 11258 Porterville Hwy BaFerstield,

Ca 93308 October 27, 2010 RECEIVED NOV

2 2010 Mr. Omer Shalev

PerrntS Otlice Air- Environmental Engineer

U S. EPA, RegiOn

9 Air Permits Office (Air-3) Environmental Protection Agency Region IX 75 Hawthorne Street San Francisco, CA 94105 Subject: PSD Permit ModUlcations Applications
for Rio Bravo Poso and Rio Bravo Jasmin Dear Omer:- Below are the responses

to your additional requests for information: The previous correspondence submitted included

a comparison

of the concentration levels of criteria pollutants from Rio Bravo Poso (Poso) and Rio Bravo Jasmin (Jasmin) current operations (for coal and

/ or petroleum coke) versus the concentration levels of the same criteria pollutants from biomass firing (at Rio Bravo Rocklin (Rocklin) and Rio Bravo Fresno (Fresno)). The concentration levels from biomass firing
at Poso and Jasmin were assumed

to be similar
to existing data from two circulating fluidized bed (CFB) boilers
at Rocklin and Fresno that are currently firing 100% biomass. That existing data is from source tests and CEMS units. Since the boilers on which these emission levels were measured were manufactured

by the same CFI3 boiler company (Combustion Engineering— Lurgi) and the basic operating parameters
are similar (temperature, residence time),

it is reasonable

to compare emission levels on
a concentration (ppm) basis. The criteria pollutant emission concentrations from the biomass boilers were less than or equal to the criteria pollutant emission concentrations from

a boiler fired on coal! petroleum coke (based on source test and CEMS data). For the sake of comparison, even though the plants (Poso and Jasmin) could take credit for some emission reductions,
the assumption

is that the emission concentrations from biomass and coal/coke are equal. Thus the future actual emissions would be equal to actual emissions. The Poso and Jasmin plants are, by utility contract, baseloaded. This type ol l)hrnl runs at full load (not ramping
up and down to meet daily load demand)
24 hours per day,

7 days per week, and 50 weeks per year. The boilers are identical and both will continue

to operate base loadedMr. Omer Shalev October 19, 2010 Page

2 as described above, when biomass

is added in to the permit. Thus, maximum projected heat inputs (MMBtu) and estimated operating hours per year will not change for future years. No change
in fuel handling will be made; fuel will continue

to be handled and fed to the boiler in the same manner
as the coal andlor petroleum coke. As you requested and to determine modification significance,
the emissions need to be compared on a mass basis, per the Code of Federal Regulations (CFR) of representative actual emissions vs. projected actual emissions

in tons per year in the tables below. The following

is a comparison

of the emissions
on a mass basis (tons per year) The actual 2005 & 2006 emissions
are used as representative actual emissions. The representative actual emissions
are based on source test data at Jasmin and Poso. These years were chosen
as representative actual emissions because the criteria pollutant emissions
are similar
to the average emissions during the years 2000— 2008. The VOC emissions during these years represent one very high year and one just below the average emission rate during that same time period. Because the concentrations

of the criteria pollutants
are expected

to be the same if the boiler fires biomass, the mass emissions
are expected

to be the same for actual and future actual emissions. The emission estimates are presented

in the following table. Rio Bravo Poso

Future

Net Actual Actual Pollutant

Avg (tpy) Actual Delta (tpy) Increase 2005 (tpy) 2006 (tpy)

(tpy)

(ipy) NOx 142.38 140.82 141.60 141.60

0

0 CO 74.77 85.08 79,93 79.93

0

0 ROG 18.89 0.77 9.83 9.83

0

0 (VOC) PM1O
9.02
8.51 8.77 8.77

0

0 S02 50.96 50.43 50.70 50.70

0

0 Rio Bravo Jasmin

F Future

I Net Actual Actual Pollutant

Avg (tpy) Actual Delta (tpy) Increase 2005 (tpy) 2006 (tpy)

(tpy)

(tpy) NOx 145.56 134.98 140.27 140.27

0

0 CO 83.78 80.74 82.26 82.26

0

0 ROG
19.73 0.77 10.25 10.25

0

0 (VOC) PMIO
7.54 8.76 8.15 8.15

0

0 S02 52.04 46.99 49.51 49.51

0

0Mr.OmerShalevOctober19,2010Page3Aspreviouslystated,Rocklinisacirculatingfluidizedbed(CFI3)boilerthatbums100%biomass.RecentRocklinsourcetestsresultswerereviewedandthelowCOemissionslevelsduringthecitedsourcetestonbiomassfuelwereconfirmed.TwoadditionalannualsourcetestsshowCOemissionsofwellbelow1ppm.LowconcentrationlevelsofVOCswerealsomeasuredattheRocklinbiornass-firedfacility.Thisresultisnotunexpectedduetotheextendedresidencetimeofthefuelinthecombustionzoneofthecirculatingfluidizedbedboiler.Thisdatawasconfirmedatanidenticalbiornass-fired(Fresno)plant.COconcentrationsfromtherecentsourcetestwerelessthan1ppm,consistentwiththeRocklindata.Thus,itisreasonabletoexpectthatRioBravoPosoandRioBravoJasminhaveusedjustifiableemissionsconcentrationsinprojectingfutureactualemissions.Ibelievethissatisfiesyourrequestforadditionalinformation.Pleaseletusknowifanythingwasnotclearorifadditionalinformationisdesired.Sincerely,l3illRossiterResponsibleOfficialVice-President,CDJasminIandCDPosoIcc:MaggieEstrada,ConstellationEnergyDr.TedGuthFacilityfilesr4