New York State Department of Environmental Conservation 

Best Available Retrofit Technology Determination 

Facility Roseton Generating Station 

Location Newburgh, NY 

Orange County 

Permit ID 3-3346-00075 

Source Category Fossil-fuel fired steam electric plant of 

more than 250 mmBtu/hr heat input 

I. Introduction 

The above referenced facility contains at least one emission source that falls under the 

requirements of the federal Best Available Retrofit Technology (BART) rule under 40 CFR Part 

51 and Appendix Y, and the New York State BART regulation as codified under 6 NYCRR Part 

249. These requirements affect an emission source which fulfills the following criteria: 

1. Falls within one of 26 specific source categories, 

2. Was not in operation prior to August 7, 1962 and was in existence on August 7, 1977, or 

underwent reconstruction between August 7, 1962 and August 7, 1977, and 

3. Has a potential to emit (collectively, with other emission sources at the facility which 

fulfill items 1 and 2) of 250 tons per year or more of any visibility-impairing pollutant. 

In accordance with BART requirements, each BART-eligible facility performed a BART 

analysis of controls for sulfur dioxide, nitrogen oxides and particulate matter. This analysis took 

into account such factors as the cost of controls, energy and non-air quality environmental 

impacts of compliance, any existing pollution control technology in use at the source, the 

remaining useful life of the source, and the degree of improvement in visibility which may 

reasonably be anticipated to result from the use of such technology. 

This document summarizes the reasoning behind the Department’s BART determination, 

including the level of controls and emission limits that constitute BART for this facility’s eligible 

emission source(s). Each analysis and BART determination was submitted to the Federal Land 

Managers (FLMs) for their review in accordance with Regional Haze State Implementation Plan 

(SIP) requirements. Comments received from the FLMs on this determination will be included 

with its official submission to the U.S. Environmental Protection Agency (EPA). 

The Department has modified this facility’s Title V permit to include the enforceable BART 

limits. The modifications were noticed in New York State’s Environmental Notice Bulletin on 

August 3, 2011. Upon completion of this public notice period, the modified permit was 

submitted to EPA for review on September 9, 2011. The final modified permit was issued on 

November 2, 2011. This permit is now being submitted to EPA as a revision to the New York 

Regional Haze SIP. 

 

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II. BART Analysis Summary 

Dynegy submitted a BART analysis for the Roseton Generating Station dated September 30, 

2010. A subsequent version, with revisions to the section dealing with the BART-eligible 

Danskammer unit, was submitted on November 2, 2010. The following emission sources had 

been previously identified as BART-eligible and were therefore included in the analysis: 

Boiler No. 1 – Emission Unit U-R0001; Emission Source SR001 

• Roseton Unit 1 is a 600 megawatt oil-fired EGU with a Combustion Engineering 

tangentially fired steam generating boiler. The unit began commercial operation in 

December 1974 and was modified in May 1992 to enable the co-firing or exclusive firing 

of natural gas. The heat input rating is 7,927 mmBtu/hr when burning No. 6 oil and 

7,369 mmBtu/hr when burning natural gas. NOx controls are a combination of fuel oil 

steam atomization, burners out of service and/or wind-box flue gas recirculation (FGR). 

Particulate emissions are controlled with a mechanical collector. 

Boiler No. 2 – Emission Unit U-R0002; Emission Source SR002 

• Roseton Unit 2 is a 600 megawatt oil-fired EGU with a Combustion Engineering 

tangentially fired steam generating boiler, and is essentially identical to Unit 1. One 

difference is the heat input when burning No. 6 oil, which is 7,691 mmBtu/hr for Unit 2. 

Similar to Unit 1, NOx emissions are controlled through a combination of fuel oil steam 

atomization, burners out of service and/or wind-box FGR, while particulate emissions are 

controlled with a mechanical collector. 

A summary of the analysis’ findings for each pollutant follows. Note that because of the 

confidential nature of Dynegy’s BART analysis, some information (e.g., cost estimates, capacity 

projections) have been omitted from this summary. 

Boiler No. 1 

• SO2

Dynegy reviewed engineering studies to identify available BART control options for 

SO2. The table below contains eight options identified; all are noted to be technically 

feasible. The associated control efficiency for each technology is also presented. 

SO2 Control Option Control Efficiency  

Wet Limestone Forced Oxidation FGD 98%

No. 6 Oil Combustion ‐ 1% Sulfur 23%

No. 6 Oil Combustion ‐ 0.7% Sulfur 46%

No. 6 Oil Combustion ‐ 0.5% Sulfur 62%

No. 6 Oil Combustion ‐ 0.3% Sulfur 77%

Gas Co‐Firing (35%) 35%

Gas Co‐Firing (60%) 60%

Gas Firing (100%) 99.96%

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The cost-effectiveness for each option is presented for the base case and for operations 

under the projected capacity factor; these figures are contained in Table 2-11 of Dynegy’s 

report. Dynegy factored in the projected capacity factor for this unit when estimating the 

costs of controls, as a baseline made on the assumption of “potential to emit” (PTE) is not 

indicative of future operations. Only the Wet Limestone Forced Oxidation FGD has 

direct energy impacts and additional fuel requirements. The modeled visibility impacts 

indicate excessive cost-per-deciview values for all options modeled. Although gas cofiring was analyzed in this study and appears to be feasible due to negative annualized 

costs, it was ultimately ruled out due to high price volatility and the potential reliability 

concerns on the state’s electric system due to limited supply, particularly during the 

winter. 

Dynegy submits that a reduction in its permitted fuel sulfur content be considered BART 

for SO2 for Roseton Unit 1. Dynegy proposes a reduction from the current 1.3 percent 

annual weighted average fuel sulfur limit in No. 6 oil, to a 1.0 percent fuel sulfur limit. 

This 23 percent reduction will result in a reduction in allowable SO2 emissions of 10,734 

tons per year. 

• NOx

Dynegy identified a number of potential BART control options for NOx. The table 

below presents the list of options. Controls which were deemed technically infeasible (as 

explained in the analysis) have been crossed out. 

NOx Control Option Control

Efficiency (%)

Separated Overfire Air (SOFA) 15

Fuel Lean Gas Reburning (FLGR) 25

SOFA + FLGR 32

Selective Catalytic Reduction (SCR) 85

Selective Non‐Catalytic Reduction (SNCR) N/A

Amine Enhanced FLGR N/A

SOFA + Amine Enhanced FLGR N/A

Fuel Specification Change 15

Gas Reburn 35

Hybrid SCR/SNCR N/A

SOFA + SCR 92

SOFA + SNCR N/A

SOFA + Hybrid SCR/SNCR N/A

Wind‐box Optimization; NOx emission limit

lowered from 0.25 to 0.20 lb/mmBtu 20

The latter NOx control option (wind-box optimization) comes at no additional cost. 

Dynegy concluded that all other controls are economically infeasible when taking into 

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account the unit’s projected capacity factor; these costs are contained in Table 2-4 of their 

analysis. Dynegy additionally demonstrated through visibility modeling that excessive 

cost-per-deciview values would accompany these control options (Table 2-7). 

Dynegy’s recommended method of BART compliance for NOx is the reduction of the 

current permitted NOx limit from 0.25 lb/mmBtu to 0.20 lb/mmBtu (based on a 24-hour 

average during the ozone season and a 30-day average during the non-ozone season) 

through wind-box optimization. This 20 percent reduction will result in a decrease in 

allowable NOx emission of 1,736 tons per year. 

• PM 

The potential PM control technologies identified by Dynegy for Roseton Unit 1 are 

identified in the table below, along with their associated control efficiencies: 

PM Control Option Control

Efficiency (%)

Electrostatic Precipitator (ESP) 90

Gas Co‐Firing (35%) 32

Gas Co‐Firing (60%) 56

Gas Firing (100%) 92

As mentioned above, the issues with gas firing or co-firing are the volatility of natural gas 

prices and reliability concerns due to the restrictions on wintertime use of natural gas in 

New York State. The ESP option was ruled out due to the high control cost when taking 

into account the projected capacity factor of Unit 1. 

Dynegy recommends that current operations be considered as BART for PM on Roseton 

Unit 1 due to the high costs of an ESP unit and the aforementioned issues associated with 

natural gas firing. Dynegy notes the secondary condensable PM emission reductions that 

will result from its proposed NOx and SO2 BART measures. 

Boiler No. 2 

• SO2

Because of the physical and operational similarities between Units 1 and 2, the SO2

control options analyzed for Unit 2 are the same as those listed for Unit 1 in the table 

above. The control efficiencies are also assumed to be the same as previously noted. 

Cost-effectiveness under the PTE and projected operating rate are presented in Table 3-

11, and costs associated with visibility improvement are in Table 3-14. 

As with Unit 1, Dynegy proposes to limit the sulfur level of No. 6 fuel oil from the 

existing 1.3 percent weight to 1.0 percent. This reduction will result in a decrease in 

annual allowable emissions of 10,734 tons 

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• NOx

The NOx control options analyzed for Unit 2 were again the same as those analyzed for 

Unit 1; see the list in the above section. The costs of controls under the PTE and 

projected operating rate are presented in Table 3-4; visibility costs are contained in Table 

3-7. 

After analyzing the control costs, additional fuel and energy requirements, and the costs 

associated with visibility improvement, Dynegy again selected windbox optimization and 

recommends a reduction of the current permitted NOx limit from 0.25 lb/mmBtu to 0.20 

lb/mmBtu (based on a 24-hour average during the ozone season and a 30-day average 

during the non-ozone season) for compliance with BART for NOx. This reduction will 

result in a decrease of allowable NOx emissions of 1,736 tons annually. 

• PM 

Dynegy again concludes that current operations should be considered as BART for PM. 

Dynegy sites the high cost associated with an ESP, and the reliability concerns of 

switching to gas (part- or full-time) to reduce emissions. The secondary condensable PM 

reductions that will result from the proposed NOx and SO2 BART measures were cited as 

also reducing overall PM emissions. 

III. BART Determination 

The Department finds that the following shall constitute BART for the Roseton Generating 

Station emission sources: 

Boilers No. 1 and No. 2 

• SO2

The Department accepts Dynegy’s BART proposal of lowering its permitted No. 6 fuel 

sulfur limit from 1.5 percent to 1.0 percent by weight. Control options were deemed 

economically infeasible on a cost-per-ton basis under recent/projected capacity factors, as 

well as on a cost-per-deciview basis, and gas firing was ruled out due to reliability 

concerns. This limit is in line with the guidance provided by EPA for sulfur in fuel of 1.0 

percent or less by weight (Appendix Y, Section IV.E.4, “SO2 limits for Utility Boilers”). 

EPA also notes in the BART rule that “the most appropriate control option for oil-fired 

EGUs, regardless of capacity, is to set limits on the sulfur content of the fuel oil burned in 

the unit” (70 FR 39133). 

It should be noted that the Department is pursuing a regulatory revision to 6 NYCRR Part 

225-1 to lower the acceptable fuel sulfur limit to 0.5 percent statewide (not including the 

New York City and lower Hudson Valley areas, which are already subject to more 

stringent limits). This revision is tentatively scheduled to be effective for 2014. The 

Department has made owners aware of this upcoming requirement and indicated it may 

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supersede BART limits such as the 1.0 percent limit recommended by Dynegy for 

Roseton Units 1 and 2. Dynegy has committed to meeting any revisions to the 

Department’s fuel sulfur requirements for No. 6 oil. 

• NOx

The Department accepts Dynegy’s proposal to lower its permitted NOx limit from 0.25 

lb/mmBtu to 0.20 lb/mmBtu through wind-box optimization. Other control options were 

demonstrated to be economically infeasible. Compliance will be measured on a 24-hour 

average during the ozone season and 30-day average during the non-ozone season. 

• PM 

The Department accepts that current operations are BART for PM. Other options were 

ruled out due to economic or technical infeasibility. These units will retain their 0.1 

lb/mmBtu particulate emission limits.