New York State Department of Environmental Conservation 

Best Available Retrofit Technology Determination 

Facility Con Ed – 59th Street Station 

Location Manhattan, NY 

New York County 

Permit ID 2-6202-00032 

Source Category Fossil-fuel boilers 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 

December 28, 2011. Upon completion of this public notice period, the modified permit was 

submitted to EPA for review on January 31, 2012. The final modified permit was issued on 

March 20, 2012. 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 

Consolidated Edison (Con Ed) submitted its BART analysis for the 59th Street Station, dated 

September, 2010. The following emission sources had previously been identified as BARTeligible and were therefore included in the analysis: 

Steam Boiler #114 – Emission Unit 5-90020; Emission Source 00114 

Steam Boiler #115 – Emission Unit 5-90020; Emission Source 00115 

• Each of these units is a Combustion Engineering fixed-tangential boiler with a design 

maximum heat input capacity of 805 mmBtu/hr. Both units burn low sulfur No. 6 fuel oil 

(0.3 percent sulfur by weight) as the primary fuel, with natural gas being used for 

ignition. They were installed in 1966. These are steam-only boilers that do not produce 

electricity and follow steam load, which results in limited operation and significant 

unused capacity. Because of the similarity in the technical and operational aspects of 

these boilers, this BART analysis combines the analyses for Boilers 114 and 115. 

A summary of the analysis’ findings for each pollutant are as follows: 

• SO2

For compliance with the low-sulfur fuel oil standards contained in 6 NYCRR Part 225-1, 

the 59th Street Station has a permit condition which limits the maximum sulfur content of 

the fuel oil to 0.3 percent by weight for Boilers 114 and 115. This low-sulfur fuel is well 

below the 1.0 percent sulfur limit in oil referenced by the Appendix Y guidance. Con Ed 

therefore requests that the current use of low-sulfur fuel be considered BART for SO2. 

• NOx

Con Ed identified seven potential control technologies as BART for Boilers 114 and 115. 

The following table lists the options identified, with technically infeasible options crossed 

out. For the options that remain feasible, the expected control efficiency has been 

provided along with the cost-effectiveness values under full operation and expected 

operation. 

NOx Control Option

Control

Efficiency

(%)

Cost Effectiveness,

8,760 hr/yr ($/ton)

Cost Effectiveness,

Expected

Operation ($/ton)

Low NOx Burners N/A N/A N/A

Ultra Low NOx Burners N/A N/A N/A

Water Injection 10 $3,368 $8,717

Flue Gas Recirculation (FGR) 10 $12,296 $31,825

Selective Catalytic Reduction (SCR) 47 $8,788 $22,747

Selective Non‐Catalytic Reduction (SNCR) 20 $9,633 $24,934

Overfire Air (OFA) 20 $6,625 $17,147

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The water injection option remains feasible under full load when considering the 

$5,500/ton threshold established by the Department for BART. When taking into 

account actual operations of these units, as directed by the Appendix Y guidance, the 

reduced capacity drives the cost-effectiveness to over $8,500/ton. 

Tables 3-1 and 3-2 of the Con Ed analysis demonstrate the visibility impacts of 

implementing the water injection control. A conservative 20 percent NOx reduction was 

utilized for this step. Visibility impact modeling indicated minimal improvement in 

downwind areas: At the maximally impacted Class I area, visibility improvement was 

0.04 deciviews (dv), or 4 percent, using the Vermont meteorological data and 0.02 dv, or 

2.6 percent, using AECOM data. Ninety-eighth percentile results were approximately 

0.01 dv (1.8 percent) and 0.01 dv (2.6 percent) with Vermont and AECOM 

meteorological data, respectively. 

Based on these results, Con Ed recommends that no additional control is needed to satisfy 

BART for NOx for Boilers 114 and 115. 

• PM 

Con Ed identified three potential add-on control technologies for PM at 59th Street 

Station: an electrostatic precipitator (ESP), a fabric filter/baghouse, and a cyclone. In 

each case, Con Ed notes that the control technology does not appear to be demonstrated 

in practice for a utility boiler that burns oil as the primary fuel. Con Ed therefore deems 

each as technically infeasible. 

Con Ed requests that current operations be accepted as BART for PM. Good combustion 

practices and the use of low sulfur fuel serve to minimize PM emissions from 59th Street 

Station Boilers 114 and 115. 

III. BART Determination 

The Department finds that the following shall constitute BART for Con Ed 59th Street Station 

Boilers 114 and 115: 

• SO2

The Department accepts the current fuel sulfur limit of 0.3 percent by weight as BART 

for SO2. This 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). 

 

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• NOx

The Department accepts the finding that no further control is required as BART for NOx. 

Although the water injection control option was within the Department’s $5,500/ton 

BART threshold under full, 24/7 operation, it exceeds $8,500/ton when taking into 

account actual operating conditions. In addition, Con Ed adequately demonstrated the 

minimal visibility improvement that would result from this type of controls, even when 

using a conservative control effectiveness estimate. All other NOx control options were 

found to be technically or economically infeasible. A NOx limit of 0.32 lb/mmBtu, based 

on a rolling 30-day average, has been established for both boilers. 

• PM 

The Department accepts the finding that no further control is required as BART for PM. 

Potential controls were found to be technically infeasible due to the operational 

characteristics of these boilers. These boilers will continue to operate with a 0.1 

lb/mmBtu particulate emission limit.