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OAR Box 1778 

Prepped by Ollie Stewart 

Document Number: 

36) ll-B-11 

Docket Number: 

A-90-06 

Printed 10/28/2008 9:50:S3 AM Sheet 36 of 276 
* -

II-B-11 

UNITeD STATc- A„ PROTECTION AGENCY 

JUL 1 OT 

M_r'.cr;,i-xur 

TFilljT^ 

JUN I ? 1991 iljj 

EPA AIR DOCK. 

SUBJECT: Applicability of PSD and VST-S to northern States 

Tower Company 

FRC!' Director 

Division of Stationery Source Enforcement 

Sandra Cardebring, Director 

Enforcement Division, Pegion V 

This is in response to your Kay 29, 19E0 mer.:o concerning 

northern States Fewer Company (KSP). You requested a determination 

aii to whether modifications proposed for' units 1, 2, 3, and 4 at 

Llack Tog generating plant and units 3, 4, -5 and c=. at High Bridge 

remiratiix: plant vculd subject the units to USPS and the generating 

plants to PSD requirements. This response is based cn the 

information presented in the attachment to your letter, and on the 

information obtained during a June 19, 1980 phone conversation 

between P.cbert Myers of my staff and Joseph Pizzano, Jr., of t.sr. 

The original design fuel for these units was 100% high sulfur, 

high Ltu Illinois coal. To comply with the state's sulfur-in-fuel 

requirement, r.SP in the early 1970's shifted to burning a blend of 

70 _ lev sulfur, low Ctu I'ontana coal and 30? Illinois coal, 

necause of the limitations in the capacity of the fuel handling and 

feeding equipment, I.SP has since been unable to burn enough of the 

blended coal to achieve the same level of steem/electricity production ac it enjoyed when it burned 100?, Illinois coal. 

The company is studying a program of rodifications to restore 

the derate the boilers currently are experiencing. The modifications principally involve the enlargement of the fuel handling and 

feeding equipment to each boiler so that the original output of 

s tear./electricity can once again be attained. This will result in 

S_2 emissions increases c£ well above 100 tons per year at each 

plant. MSP reports that particulate emissions will increase as 

veil, hcvevor, there is no indication as to the effect the 

.v.cc.ification will have on t-Px emissions. The issue is whether 

1-.1.T>'• or PSD rocuircment.-- v.culd nnply to this proposed modi f ication. 

CONCURO-MCGS 

T 
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a modification is defined at 40 CFP. 60.2(h) as "any 

physical change in, or change in the method of operation of, an 

existing facility which increases the amount of any air pollutant 

(-.r. v.-hich a standard applies) emitted into the atmosphere by that 

facility or \:hich results in the emission of any air pollutant (tc 

v.hich a standard applies) into the 'atmosphere not previously 

emitted". This is limited somewhat by 40 CFP CO. 14 (e)(2), as 

revised July 1, 1979, which states that an increase in production 

rate cf an existing facility is not considered a medification if 

that increase can be accomplished without a capital expenditure on 

that facility. Capital expenditure is defined at 45 FR „fil7, ^0 

CFR 6C.2(bb) (January 23, _9G0) and. means an expenditure for a 

physical or operational change to an existing facility which 

exceeds the product of the applicable IPS asset guideline and the 

existing facility's basis as defined in the IR code. 

It appears that l-T>P is undergoing an increase in production 

rate. This would be subject to MSFS if it involves a capital 

expenditure on the facility, the individual boiler. It is thus 

essential to determine if the components being enlarged, the fuel 

handling and feeding equipment, are part of the affected facility. 

V7e have been in contact with CACF3 and they have providedgeneral guidance as tc what they consider tc be the components of 

the affected facility. Under EPA's HID for proposed Particulate 

flatter Emission Standards from Electric Utility Steam Generating 

Units (450/2-7P-C06a, July 197B) boiler components include burners 

(pulverizer, crusher, stoker), combustion air system, steam generatier system (firebox, tubes) and draft system. 

Joseph Eizzano mentioned to r.ofcert Myers, that the changes 

being considered include changing the superheater spacing, adding 

scot blowers to the boiler, and increasing pulverizer size. Since 

the superheater and pulverizer are considered part of the affected 

facility, replacement or redesign which would change the physical 

characteristics of these components may be a case where modification provisions apply. A final decision must await a complete 

description by t.SP of the specific chnnges tc be made and equipment 

involved. 

For purposes of PSD applicability "curing the period of the 

••"ehruary 5, 19G0 stay (4_ IT. 7P00) , major modification is 

determined by a source's potential to emit under both the 

forteir.ber 5, 1979 (44 FF. !319_4) proposed TSD regulations and the 

Juno 19, 1978 (43 FP. 2C3f-R) regulations. Major modification 

considers-changes over the entire source, the generating plant, 

rather thnn channes for each boiler. 
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Under the June 19, 197C regulations major modification is 

defined as any physical change in, change in the method of operation of, or addition to a stationary source which increases the 

potential emission rate (regardless of any emissions reduction 

achieved elsewhere in the source) of any air pollutant regulated 

under the .'.ct by ICO tens per year for fossil fuel-fired toilers 

totaling ever 250'mm Etu per hour heat input. Potential to emit 

means the capability at maximum capacity unless otherwise limited 

ty an enforceable permit condition (43 FR 26404), to emit a 

pollutant in the absence of air pollution control equipment. 

Under the September 5, 1979 proposed FSD regulations, potential to emit is the capability at maximum design capacity to emit a 

pollutant after the application of air pollution control equipment, 

i-'ajcr modification is defined as any physical change in or change 

in the method of operation of a major stationary source, or series 

of contemporaneous physical changes in or changes in the method of 

operation of a major stationary source that would result in a 

significant net increase in that source's potential to emit the 

pollutant for which the stationary source is major. For SO2 and 

particulate matter ten tons was proposed to be a significant net 

increase. 

Under the June 19, 197G regulations (43 FR 26404) and the 

September 5, 1979 proposal, (44 FR 51948) potential tc emit 

includes enforceable permit conditions on the type of materials 

combusted or processed. Thus, for the two generating plants in 

c.ua.ticn, potential to emit would include Minnesota's sulfurin-fuel requirement under both definitions. 

Generating potential emissions is limited by the quantity of 

fuel the source is capable of combusting. The ability of the 

generating plants to combust additional fuel subsequent to the 

modification results in increased emissions. Since the generating 

plants were not capable of accommodating this additional fuel 

•without changes to the fuel handling and feeding equipment, this 

would represent an increase in the potential to emit. KSP would be 

subject to PSD review if the changes would result in an increase of 

100 tens per year of uncontrolled SO2 or particulate matter 

omissions and 10 tons per year of controlled emissions. The 

June 18, 1978 regulations would be applied. This determination 

a_sumos that the sources in question are located in attainment or 

unclassified areas and that no additional controls will be added to 

the sources to offset any emission increase. 

The final PSD regulations are expected to be promulgated 

heforo the end of this month. If the proposed modifications of the 

r:ourcos in question taV.e place after promulgation, the new 

regulations will apply (providing the sources cannot he 
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"grandfathered".-. Under the lastest draft of these regulations, a 

source- must tnve an increase of 40 tons of particulate or SC-, 

controlled emissions in order to be subject tc PSD review. These 

r-i-julatic..- also fallow a source's potential to emit to include 

en_crce_tle limitations cn hours of operation or type or amount of 

material combusted or processed. 

This response was prepared in conjunction with the Office of 

Air Quality Planning and Standards and the Office of General 

Counsel, if you have any questions concerning this determination, 

please contcct either Robert Kyers or Janet Littlejc-hn of my staff, 

at FTS 75 5-2564. 

Edward E. Reich 

cc: Peter Kelly 

Peter V.yc>.off 

Larl Salo 

Dave Patrick 

l.alt Stevenson 

Jim. v.'eirold 

Li;: 341 .RKyersmcb: 7/2/80: 3202: 52564