**Page 1 of 16**


### NSR ENGINEERING EVALUATION

**Connecticut Department of Environmental Date Recv'd: 05/11/2009 Protection PAMS No.: 200901310**  **Bureau of Air Management EPE No.: 22584 Permit No.: 107-0056**  **Prepared by: J. Grillo Date Prepared: Dec 2009** 
**Firm Name:Montville Power LLC Address:74 Lathrop Road, Uncasville, CT 06382**  **Contact Person (title & phone no.):Cynthia Karlic Equipment Location:74 Lathrop Road, Uncasville, CT 06382**  **Equipment Description:Major Modification to Unit 5 – Converting to Stoker fired 42 MW biomass baseload boiler with 82 MW of peaking**  **firing natural gas or ultra low sulfur (15 ppm) distillate oil**

**PART I. - Annual Emission Review: Tons Per Year**

Pollutant Premises PTE P ermit PTE New Premises

PTE ***** ***** PM-10/2.5 227.1 33.1 (filt.)

36.3 ***** (cond.)

67.3 ***** (total) 256.8 (filt)

256.8 (total)

SOx 7706.8 60.4 6420.3

NOx 5032.9 161.9 4355.9

VOC 289.5 25.6 285.3

CO 1077.8 265 1204.8

***Note: Condensable PM-2.5 and total PM-2.5, including condensable PM, are estimated**
**based on EPA AP-42 emission factor for condensable PM from wood residue, Table 1.6- 1, Fifth Edition, September 2003.**  **Initially, testing for filterable PM-2.5 shall be required. Within one year following the US EPA’s promulgation of a condensable PM** 
**2.5 reference test method, the Permittee shall test for both filterable and**

**condensable PM-2.5.**

 Note: Includes the reduction offset PTE of No. 6 fuel oil to No. 2 ULS distillate**  **fuel oil and the increases from biomass firing.**

### Montville Power LLC **Page 2 of 16**



### PART II. - Emissions Summary (TPY) for Major Modification **Determination** (see Attachment C)

Pollutant Actual Emissions (2 yr avg)* PTE

As limited by permit Actual Emissions Increase/

Decrease* Net Emissions

Change Significance
Levels Table 3a(k)-1 Increase equal
to or greater

than Table

3a(k)-1? (Yes or NO)

PM 0.09 33.1 2.1 35.2 25 Yes

PM-10 0.09 33.1 2.1 35.2 15 Yes

PM-2.5 0.09 67.3 2.1 69.4

SO 2 31.6 60.4 28.8 40 No

NOx

(ozone) 24.2 161.9 137.7 25 Yes

NOx

(NAAQS) 24.2 161.9 137.7 40 Yes

VOC 1.05 25.6 24.55 25 No

CO 4.6 265 260.4 100 Yes

Pb 0.001 0.6



### *Note: Ash and fuel handling equipment.

**PART III. - Emission Standards Review and Regulatory Authority:**

a. **Reg Standard Allowable Rate Basis**

PM: Opacity

20% six minute average

27% one 6-minute period/hr

40 CFR Part 60.43b(f) & (g) 10% six minute average

(Steady state only)

See Note below 1

PM10/2.5:

0.10 lbs/MMBtu (all fuels)

RCSA §22a-174-18(e)(1) 0.012 lbs/MMBtu (biomass)

0.024 lbs/MMBtu (oil)

0.0076 lb/MMBtu (gas) 1

SO
x :

RCSA 22a-174-19(a)(2)(i):

1% by weight dry basis;

1.1 lbs/MMBtu

CGS §16a-21a:

0.3% S by weight 0.025 lbs/MMBtu (biomass)

0.006 lbs/MMBtu (ULSD)

0.0017 lbs/MMBtu (gas) 3

2

2

### Montville Power LLC **Page 3 of 16**



### PART III. - Emission Standards Review and Regulatory Authority, cont.

**Reg Standard Allowable Rate Basis**

NO
x :

0.2 lbs/MMBtu (gas/distillate)

0.3 lbs/MMBtu (biomass)

RCSA §22a-174-22(e)(1)

RCSA §22a-174-22(e)(2)(A) 0.06 lbs/MMBtu

For all fuels 1

VOC:

RCSA §22a-174-20 0.01 lbs/MMBtu (biomass)

0.0014 lbs/MMBtu (ULSD)

0.055 lbs/MMBtu (gas) 1

3

3

CO:

RCSA §22a-174-21 0.1 lbs/MMBtu (biomass)

0.036 lbs/MMBtu (ULSD)

0.084 lbs/MMBtu (gas) 1

3

3

MASC:

Ammonia Slip: 257,383 ppm

RCSA §22a-174-29 18 ppm 1

**NOTE: RCSA 22a-174-18(j)(2) requires compliance with the visible emissions standard set forth in the applicable NSPS. This unit will be subject to Subpart Db after the**  **modification to biomass firing.**

**Opacity standards apply at all times, except during periods of startup, shutdown, or malfunction [40 CFR 60.43b(g)].** 

**During periods other than startup, shutdown and malfunction (i.e. fuel switching, soot blowing, load changes) opacity shall not exceed one 6-minute period per hour of**  **not more than 27 percent opacity [40 CFR 60.43b(f)].**

The basis for these emission rate calculations are:

1. Manufacturer’s Data

2. Calculated from 0.0015% S or less in ULS distillate oil.

3. AP-42, Table 1.6-2 (9/03); Table 1.3-1 (9/98); Table 1.3-3 (9/98) Table 1.4-1 (7/98); Table 1.4-2(7/98)

b. Source subject to: NSPS, Part 60 , Subpart A, Subpart Db ;

c. Hazardous Air Pollutant compliance (RCSA 22a-174-29) yes no N/A (see Attachment A)

### Montville Power LLC **Page 4 of 16**



### PART IV. - Ambient Impact Analysis:

Source is subject to Ambient Impact Analysis yes no If no, check applicable box: PM-10/SO

x < 3 tpy NO
x /CO < 5 tpy

a. SSSHG analysis

3 < PM-10 < l5 tpy 3 < SO

x < l5 tpy

Date SSSHG completed/approved: (see attachment B1)

b. Screening

“Screening” is required when the allowable emissions for all equipment being permitted contemporaneously exceed any of the limits below.

5 < CO < l00 TPY 5 < NOx < 40 TPY

Date screening completed/approved: (see Attachment B2)

Screening analysis not required since SSSHG was completed/approved.

c. Refined Modeling

“Refined Modeling” is required when the allowable emissions for all equipment being permitted contemporaneously exceed any of the limits

below.

PM-10 > l5 tpy SO
x > l5 tpy CO > l00 tpy NO
x > 40 tpy Pb > 0.6 tpy

Date refined modeling completed/approved: 12/04/09 (see Attachment B)



### PART V. - PSD Review:

Source is subject to PSD Review yes no (see Attachment B)

Source netted out of PSD Review yes no (If yes, see Attachment C1)

a. Source has significant impact (per RCSA 22a-l74-3a(i)) for:

PM-10 SO 2 CO NO
x Dioxin Pb

b. PM SO
x NO
x Increment Consumption analysis completed.

c. Pre-construction monitoring required for ; waived

d. Visibility, soils, and vegetation impact analysis approved

### Montville Power LLC **Page 5 of 16**



### PART V. - PSD Review, continued:

e. General commercial, residential, industrial and other associated growth analysis approved

f. Ambient air quality impact projection analysis approved



### PART VI. - Non-attainment Review:

Source is subject to non-attainment review yes no

a. Pollutant(s): NOx

b. Emissions Increase over the last 5 years (tons): None

c. Offset Ratio: 1.2

d. Offsets Required: (1.2 x 161.9) = 195 tons Internal Offsets: 24.2 (Average of actual emissions from 2007/2007) **Offsets to be acquired: 195 – 24.2 = 171**



### PART VII. - Control Technology Analysis:

a. BACT/LAER/MACT Compliance yes N/A

b. BACT/LAER/MACT Utilized: (See Attachment D)

Pollutant BACT/LAER/MACT PM 0.026 lb/MMBtu (condensable and filterable); Dry ESP
CO 0.1 lbs/MMBtu; Oxidation Catalyst and good combustion.
VOC 0.01 lb/MMBtu; Oxidation Catalyst and good combustion.

NOx 0.06 lb/MMBtu; RSCR: LAER

SOx 0.025 lbs/MMBtu; Low sulfur fuels
Ammonia Ammonia slip < 18 ppm.



### PART VIII. Emission Testing Requirements:

a. Stack emission testing shall be required for the following pollutant(s):

None at this time
PM-10 SO
x NO
x CO VOC Pb Opacity Other (HAPS): Hydrogen Chloride (HCL) ; Ammonia

b. Testing schedule included in permit: yes no N/A

c. AE 405 Stack Test Referral Form Completed: yes no N/A

d. Recurring Tests required? yes no (If yes, notify Stack Test Group) Frequency: Every 5 years

e. CEMS requirements : None at this time

SO
x NO
x CO VOC

Opacity Other: Ammonia, RSCR Temperature, Oxidation Catalyst Temperature

### Montville Power LLC **Page 6 of 16**



### PART IX. - Administrative Criteria Review:

a. Air quality status

ozone: severe non-attainment serious non-attainment

PM2.5: attainment non-attainment

b. Premises size: <l5 tpy; > l5 <l00 tpy; > l00 tpy

c. Source size: <l5 tpy; > l5 <l00 tpy; > l00 tpy

d. The source is an **existing** fossil fuel fired unit that serves a generator with a nameplate capacity of 15 MW or greater or is a new fossil fuel fired boiler or indirect heat exchanger with a maximum heat input capacity of 250 MMBTU or more: yes no (If yes, notify P&S NOx Budget Program )

e. Fee: $15,000 ( See Attachment D )



### f

**.** Signatory Responsibilities authorized yes no n/a (See Attachment E)

g. Source entered in SIMS P&E Tracking System yes no

h. Source entered in SAS Permit Tracking System yes no

i. Source is in the Coastal Boundary yes no Source is in the Coastal Area yes no (No impact, see memo from Kristal Dorismond, dated 09/23/09)

j. Source is on federally recognized Indian lands yes no

k. Source is in a Natural Diversity Data Base Area yes no

l. Source is subject to conservation/preservation restrictions yes no



## See attached map

t S O Mi ft P i t d

### Montville Power LLC **Page 7 of 16**



### PART IX. - Administrative Criteria Review, continued:

m. The source to be permitted combusts coal, waste oil, tires, recycled materials, construction/demolition debris, wood products, biological waste or any other non-fossil fuel that may contain or emit toxic air pollutants yes no Gary Ginsberg & Brian Toal notified by e-mail on
08/26/09

The source to be permitted is major for federal HAPs yes no

n. The applicable facility is located in a municipality on the Connecticut Department of Economic and Community Development (DECD) list of distressed municipalities or in the defined census block to be considered under Public Act 08-94 and the Environmental Justice Policy.

yes no



### PART X. - CGS 22a-6 and 22a-186a Compliance:

-6g yes no n/a Certified Notice of Application

-6 Ρ yes no n/a Posting of Notice Certification

-6m yes no n/a Compliance Information (See Attachment G)

-186a yes no n/a Conformance Certification



### PART XI. - Special Requirements:

Based on modeling: The Permittee shall not operate the existing 2.5 MW diesel generators, R107-0021 and R107-0022, for more than 30 hours/day combined when firing Unit 5 on biomass.



### PART XII. - Summary:

On May 11, 2009 Montville Power, LLC submitted an application to convert their 82 MW natural gas and No. 6 oil fired boiler (Unit 5) to a stoker fired 42 MW biomass (wood) boiler with 82 MW peaking capability firing either natural gas or ultra low sulfur distillate oil. The fossil fuel/peaking firing capability will be limited to a 7% annual capacity factor. This boiler currently operates under registration R107-0017, Trading Agreement & Order No. 8216A (NOx), Consent Order No. 1887 (Opacity) and utilizes an ESP for particulate control. Once the project is complete the NOx trading order and Opacity Consent Order will no longer be required as the addition of state-of-the-art NOx and particulate controls will reduce these pollutant emission rates to below all state and federal limits. The expected start of commercial biomass operation of this unit is June 2011.

The applicant was required to apply for a NSR permit pursuant to 22a–174- 3a(a)(1)(B) since this plant will be a major modification to an existing major source, [RCSA 22a-174-1(55)] where there is a significant net increase in emissions for PM/PM-10, NOx and CO emissions pursuant to RCSA 22a-174- 3a(k)(2)(B). This premises is located in a non-attainment area for ozone pursuant to RCSA 22a-174-1(98).

This premises is located at an existing electrical generating facility and major source of air pollution. Currently there is one other No. 6 oil utility boiler on the premises along with two (2) auxiliary boilers, two (2) 2.75 MW diesel generators and two (2) other diesel engines. The premises operates under Title V permit number 107-0043-TV.

### Montville Power LLC **Page 8 of 16**



### PART XII. – Summary, continued:

This project is subject to PSD review for PM-10, NOx and CO pursuant to Sec. 22a-174-3a(k). In addition, this source is subject to non-attainment/LAER review for NOx pursuant to Sec. 22a-174-3a(l). The boiler will be subject to the New Source Performance Standard (NSPS) 40 CFR Part 60 Subpart Db once the conversion to fire biomass is complete. This determination was made based on consultation with EPA Region 1 and analysis of the NSPS rules concerning “modification”. The applicant will be required to submit an application for a non-minor Title V permit within one (1) year after becoming subject to the Title V provisions pursuant to Sec. 22a-174- 33(f)(2)

**.** The applicant initially indicated that the potential to emit for a federal HAP, hydrogen chloride (HCL) would be greater than (10) ten tons/year, making this source a new major source of HAPs and would be subject to RCSA Sec. 22a-174-3a(m), otherwise known as a Sec. 112(g) MACT determination. This determination was based on using AP-42 emissions factors for HCL. However, on September 9, 2009 the applicant submitted additional updated emission data that shows that this source should not be considered a major source of HAP for HCL based on actual stack test data from similar plants in New England and revised engineering estimates. The applicant has agreed to accept a limitation for HAP emissions that will restrict the boiler to less than 10 tpy for any individual HAP and less than 25 tpy for all HAP in aggregate. The permit has requirements to stack test for HCL to ensure that this source will not emit more than the major source threshold of ten tons per year. All other HAP emissions estimates have been based on AP-42 factors for wood burning.

The proposed modification to the plant consists of converting the plant to astoker grate firing clean biomass as defined in RCSA 22a-208a-1 and CGS 22a209a along with the addition of new low NOx burners and the conversion from No. 6 oil to ultra-low-sulfur distillate fuel oil, 15 ppmvd sulfur content. There will be no construction and demolition (C&D) or regulated wood fuel combusted in this boiler. When firing biomass the plant will have a nominal electrical output of 42 MW and when firing natural gas or distillate oil the plant will operate at 82 MW for up to a 7% annual capacity factor. There will be no co-firing of biomass and fossil fuel except during the transitional period from biomass to fossil fuels. The existing steam turbine will not be modified and no increase in maximum rated capacity is planned for the boiler/steam turbine. The modification to the plant will use state-of-the-art emissions controls consisting of the following: a newelectro-static precipitator (ESP) to control particulate emissions; multiclones to collect fly ash from the exhaust stream; a new regenerative selective catalytic reduction (RSCR) unit to control NOx emissions; and oxidation catalyst to control CO and VOC emissions along with some organic
HAPs emissions.

Biomass fuel will be delivered to the site by local roadways via tractor trailers and screened for oversized material. Any oversized material will be hogged to appropriate fuel size specification and then transferred by conveyor to a storage pile and fed to the boiler by an enclosed conveyor system. Fly ash will be collected at the multi-clone and ESP hoppers, collected and trucked off site for disposal. No single fugitive particulate point sources have a potential to emit (PTE) greater than 15 tpy and the fuel/ash handling system will not require an individual NSR permit. All fugitive dust particulate emissions from the fuel/ash handling have been included in the permit and PSD review for particulate matter.

### Montville Power LLC **Page 9 of 16**



### PART XII. – Summary, continued:

**NSPS Requirements:** This boiler is not currently subject to any New Source Performance Standard as it was constructed prior to the applicability date of the boiler standards. After the modification the boiler will be subject 40 CFR Part 60 Subpart Db: Industrial-Commercial-Institutional Steam Generating Units pursuant to 40 CFR 60.2 where there will be a change the method of operation which increase the amount of any air pollutant. In this case there currently is no NOx control and the NOx emissions rate before the RSCR is installed increases from 170 lbs/hr to 578 lbs/hr subjecting the boiler to Subpart Db because of the modification. Subpart Db contains emission standards for PM, NOx, and SO 2 . Subpart Db [60.43b(h)(1)] limits the boiler PM emission rate to 0.03 lb/MMBtu and there are no specific emission
standards for NOx and SO 2 for firing biomass. The applicant has proposed a PM emission rate of 0.012 lbs/MMBtu. The proposed natural gas and
distillate emissions rates for NOx and SO 2 are below the NSPS standards and will be verified with stack testing and/or CEM data. Based on the proposed emission rates and method of operation the boiler will easily comply with the applicable emissions standards required by the NSPS. All required monitoring, record keeping and reporting will be complied with for Subpart Db. Subpart Db requires that either a stack test or a particulate CEM can be used as a method of compliance for particulate matter. The proposed plant will be required to stack test to comply with the permit particulate
emissions rate.

RCSA 22a-174-18(j)(2) defers compliance of the State opacity standards to the NSPS if a standard applies. Pursuant to 40 CFR 60.43b(f) the visible emissions (opacity) are to be less than 20% for (6-minute average) and less than 27% for one 6-minute period/hour. The permit will limit the steady state opacity to 10% (six-minute block) and will use the NSPS 27% limitation as the maximum opacity limitation. The NSPS and permit opacity requirementis significantly more restrictive than the RCSA standard of 20% in any sixminute block average; or 40% reduced to a one-minute block average.

**Control of NOx:** The boiler is subject to Sec. 22a-174-22(b)(1)(A)(ii) since it is a major stationary source of NOx and has a heat input greater than 5 MMBtu/hr. Pursuant to Sec. –22(e)(2), this boiler must meet an emission limit of 0.3 lbs/MMBtu when burning biomass and 0.2 lbs/MMBtu when firing fossil fuels. The applicant has proposed an emission rate of 0.06 lbs/MMBtu for all fuels.

This source is currently an existing unit subject to RCSA 22a-174-22c Clean Air Interstate Rule (CAIR). After the modification the unit will be
considered a new source under CAIR and additional NOx allowances will be assigned as there will be an increase in NOx emissions over the recent historical average.

This unit is subject to the provisions of Sec. 22a-174-22(k), Emission testing and monitoring, and 22a-174-22(l) Reporting and record keeping.

**Control of PM-10:** Pursuant to RCSA 22a-174-18(e)(1), the boiler shall not exceed 0.1 lbs/MMBtu for all fuels. The permittee has proposed an emissions rate of 0.012 lbs/MMBtu for biomass with lower rates for gas and distillate firing.

### Montville Power LLC **Page 10 of 16**



### PART XII. – Summary, continued:

**Control of SOx:** Pursuant to RCSA 22a-174-19(a)(2)(i) the boiler shall not exceed 1.1 lbs/MMBtu for biomass firing. The applicant has proposed an emissions limit of 0.025 lbs/MMBtu. Pursuant to CGS §16a-21a the sulfur content for liquid fuels shall not exceed 0.3% by weight. The applicant has proposed using
ultra low sulfur distillate fuel oil with a sulfur content of 0.0015%.

**Non-attainment/LAER NOx Offsets** : This source is subject to non-attainment/LAER review for NOx pursuant to Sec. 22a-174-3a(l)(1)(A). Pursuant to Sec. 22a-174-3a(l)(4)(B)(x) the applicant must demonstrate that either internal NOx offsets or certified external emission reduction credits (ERCs) are used to offset actual NOx emissions at a ratio of 1.2:1. Actual NOx emissions for this project are calculated to be 161.9 tons/year.

The actual NOx emissions from this boiler prior to the modification for calendar years 2007/2008 have been reviewed and the average has been determined to be 24.2 tons/year. Using the equation below, it has been determined that the applicant will be required to obtain 171 tons/year of external NOx ERCs to comply with the LEAR requirements of Section 22a-174- 3a(l)(4).

The required NOx ERCs has been calculated as follows:

Total Offsets Required = (Actual emissions x offset ratio) = (161.9 TPY x 1.2) = 195 TPY

External ERC Offset = (Total Offsets)-(internal offsets) External ERC Offset = (161.9 TPY x 1.2) – 24.2 = **171 Tons/year**

The applicant will be required to obtain 171 tons of certified external
emissions reductions NOx credits from either a severe or serious NOx nonattainment area. The acquisition and transfer of the emissions reductions must be approved by the Bureau of Air Management prior to the final construction/operating permit being issued.

Pursuant to Section 22a-174-3a(l)(2), the applicant is required to submit an ‘Analysis of Alternatives’. This review has been submitted and has been part of the review process. The applicant has demonstrated that the proposed project’s benefits outweigh the adverse environmental impacts based on the following:

• This premises is currently an electrical utility plant and is an ideal location for additional utility development compared to developing a green field location.

• The State of Connecticut has mandated that renewable energy generation is part of the makeup of the overall generating portfolio.

• This boiler will be base loaded with renewable biomass fuel and will be retrofitted with state-of-the-art controls that are currently not
utilized on this unit.

• The boiler is currently used to supply 82 MW during peak demand using residual oil. After the conversion to biomass the plant will provide 42 MW of reliable base load electricity and up to 82 MW for peaking purposes firing either ULS distillate oil or natural gas along with using state-of-the-art controls.

### Montville Power LLC **Page 11 of 16**



### PART XII. – Summary, continued:

• The boiler currently fires No. 6 residual oil and will be converted to fire ULS distillate fuel oil which will have a significant reduction in SOx and particulate matter emissions. In addition biomass and natural gas have inherently low SOx emissions when compared to
residual oil.

LAER for NOx has been determined to be RSCR, an emissions rate of 0.06 lbs/MMBtu and the requirement to obtain 171 tons of external NOx ERC offsets, in combination with the 24.2 tons of internal emissions reduction offsets, prior to issuance of final permit to construct/operate.

**BACT/LAER Requirements:** BACT applies to the following pollutants: PM, NOx, SOx, VOC, CO, and ammonia pursuant to Sec. 22a-174-3a(j)(1)(D) where potential emissions are greater than 15 tons/yr from a modification to an existing source.

As stated previously, LAER also applies to the NOx emissions pursuant to 22a-174-3a(l)(1)(A).

The determination of BACT for the above pollutants was based on the information provided in the application of similar biomass energy projects throughout the country and the following:

• Review of the potential emissions and minimum regulatory requirements.

• Review of the EPA RACT/BACT/LAER Clearinghouse to identify various
control methods.

• Review of the technical feasibility of each control method.

• Rank the control technologies using a “top-down” approach, where energy, economic and environmental impacts are used to determine the best control technology for the project.

Although there are alternate methods of control technologies identified in the permit application, the proposed methods have been shown by the applicant to comply with the BACT requirements pursuant to Sec. 22a-174- 3a(j). Some of the other control technologies considered provide no additional reduction in emissions, are technically infeasible, or have not been successfully demonstrated in practice. The permit will require the applicant to resubmit for review and approval an updated BACT analysis if
construction has not commenced within 18 months of the final construction/operating permit.

The BACT determination for the pollutants identified above was determined based on following:

**PM/PM-10:** The applicant identified the following control technologies: Fabric Filter Baghouse, Wet Electrostatic Precipitators and Dry Electrostatic Precipitators. Wet ESP’s have been shown to be technically infeasible because they would cool the exhaust gas to below the operational temperature of the RSCR control device, affecting NOx control.

Additionally, the PM loading would exceed the design specification for effective control. The fabric filter would also not be technically feasible for stoker fired wood boilers as there would be a threat of baghouse fires from embers not removed in the exhaust stream. The only technically feasible option is the use of a dry ESP. The boiler currently utilizes an ESP, but it will be replaced by a new and larger unit to handle the PM loading when firing biomass.

### Montville Power LLC **Page 12 of 16**



### PART XII. – Summary, continued:

**NOx:** The applicant identified the top level of controls for NOx as regenerative selective catalytic reduction (RSCR) and selective catalytic reduction (SCR). For biomass firing RSCR has been shown to be the top level of control at 0.06 lbs/MMBtu. For firing natural gas SCR has been shown to be the top level of control at 0.035 lbs/MMbtu on gas only boilers, not firing biomass. There has not been any distillate firing boilers identified with an emissions rate of less than 0.06 lbs/MMBtu. Since the firing of fossil fuel will have an annual capacity factor of 7%, there is no technical reason to require the use of SCR to control NOx emissions during fossil fuel firing. BACT/LAER for NOx has been recommended to be the use of RSCR with an emissions rate of 0.06 lbs/MMBtu for all fuels.

**SOx:** The applicant identified that has been no stoker biomass or fossil fuel fired boiler that has been required to install an acid gas control to meet BACT. The inherently low sulfur content of clean wood along with the ultra low sulfur distillate oil and natural gas use represents BACT for SOx
emissions.

**CO and VOC:** The applicant identified that catalytic oxidation is the only
current method to reduce CO and VOC emissions available at this time. There are technical issues with using oxidation catalysts such as catalyst fouling from ash and low excess oxygen in exhaust gas. The analysis has shown that while there are some units that have been permitted to use oxidation catalysts, none have been constructed. The applicant has proposed to use a catalyst to control CO and VOC as BACT. Emission rates will be verified by
an initial stack test and with a CEM for CO which can also serve as a surrogate for VOC emissions.

**Ammonia:** The ammonia emissions are a direct result of the RSCR NOx control system. Ammonia is injected into the RSCR to react with NOx in the flue gas. The reaction produces nitrogen and water which is emitted through the stack. There is some un-reacted ammonia that passes through the RSCR and is commonly called “ammonia slip”. The applicant will optimize the RSCR to get the greatest NOx reduction along with the least amount of ammonia slip.
These emissions limits will be verified with the use of CEMs recorders.

**BACT/LAER recommendations:**

**Pollutant BACT/LAER Compliance Demonstration** PM/PM-10 Dry ESP 0.026 lb/MMBtu Stack test; COMS(10% 1 hour-block)

NOx 0.06 lbs/MMBtu all fuels **(LAER)**
171 tons of emission reduction
credits **(LAER)** RSCR (BACT) Stack test; CEMS(24 hour-block)

SOx Use of inherently low sulfur
fuels 0.025 lbs/MMBtu Stack test; CEMS(3 hour-block)

CO Oxidation catalyst and good combustion practices 0.1 lbs/MMBtu Stack test; CEMS(8 hour-block)

VOC Oxidation catalyst and good combustion practices 0.01 lbs/MMBtu Stack test; CO CEMS as surrogate

NH 3 Slip Complying with emission limit of 18 ppmvd, and optimization of RSCR system Stack test; CEMS (24 hour-block)

### Montville Power LLC **Page 13 of 16**



### PART XII. – Summary, continued:

**Prevention of Significant Deterioration (PSD) Requirements:** Pursuant to 22a-174-3a(k)(2)(B) major modifications are subject to PSD review if the source has the potential to emit above the net emissions increase above the significant emission rate thresholds listed in Table, 3a(k)-1 of the RCSA. The potential net emissions for the attainment pollutant PM-10 is above the significant threshold listed in Table 3a(k)-1. The other pollutants that have a significant net increase are NOx and CO.

Refined modeling/PSD review was performed for PM10/2.5, CO, SO 2 , and NOx. The modeling report, see memo from Jude Catalano dated 12/04/09, determined that the facility would not cause or contribute significantly to a violation of the State AAQS, federal NAAQS or federal PSD increments.

The PSD modeling also requires that additional analysis for impacts to visibility, soil, vegetation and growth analysis be conducted.

• The visibility impact was not required since the nearest federal Class I Area is farther than 200km away.

• Compliance with the SO 2 and NOx NAAQS ensures adequate protection of soils and vegetation.

• The growth analysis shows that this project would not have a significant effect on local air quality.

Pursuant to Sec. –3a(k)(8)(iv), the owner /operator of a PSD source must include “a schedule for the construction of the subject source or modification.” Montville Power, LLC estimates that construction would begin in March 2010 and startup/commissioning would begin in June 2011.

**Acid Rain:** The applicant currently has an Acid Rain permit covering the two existing utility boilers. The Permittee shall comply with all applicable requirements of the Federal Acid Rain Program codified in Title 40 CFR Parts 72-78, inclusive, for this boiler.

**Sec. –29 MASC:** This source complies with Sec. 22a-174-29 maximum allowable stack
concentrations for all identified HAPs at this time. An initial stack test will be required for ammonia and HCL. Stack testing for HCL will be repeated every five years from the last test.

The proposed permit has requirements that will limit all individual and any combination of HAPs listed in Section 112(b) of the Clean Air Act Amendments of 1990 to less than 10 tons and 25 tons/year respectively. The applicant will show compliance with these limitations with stack test, AP-42 emission factors and/or fuel sampling.

The applicant currently has an active application for two peaking GE LM6000 turbines for the premises. On April 15, 2009 the applicant requested that these applications be withdrawn. Pursuant to RCSA 22a-174-26(m)(1), the commissioner shall retain 50% of any application fee if the Commissioner has not published the tentative determination on the application. Since these applications were never acted on by the Department, the applicant is due 50% ($750.00) of the two application fees which will be transferred to this application by CPPU. The refund is included in the calculation of the permit

fee.

### Montville Power LLC **Page 14 of 16**



### PART XII. – Summary, continued:

**Compliance History Review:** The compliance record was reviewed in accordance with the Environmental Compliance History Policy. The applicant’s submitted compliance information form was reviewed along with agency records, including the SIMS Enforcement database, for information to evaluate the applicant’s compliance history and the relevance of such history to the activity for which authorization is being sought. Additionally, a review of air program compliance was requested from the Enforcement Section and that response forms a part of this record.

There are currently no enforcement actions that prevent this permitting process from moving forward.

Based on the information submitted by the applicant, this engineering evaluation and the compliance history review, the granting of a permit to construct and operate a 42 MW biomass/82 MW gas/distillate power plant is recommended for Montville Power, LLC.

/s/ James Grillo 1/14/10 James A. Grillo, APCE Date

**Approvals:**

**/s/ Kiernan Wholean 1/14/10**
**Kiernan Wholean Supervising APCE** 

**/s/ Richard Pirolli**
**Richard A. Pirolli**
**Assistant Director**

/jad

### Montville Power LLC **Page 15 of 16**



### NSR Engineering Evaluation Attachment Coversheet **Connecticut Department of Environmental Protection Bureau of Air Management** 

For Attachment:

A Hazardous Air Pollutant (HAP) Review

B Ambient Impact Analysis Refined Modeling Increment Consumption Analysis Additional Analysis (soils, visibility, growth, etc.)

C Premises Non-attainment Pollutant Summary C1 Netting analysis (See Part V) C2 5 yr aggregation (Deminimis Rule) (See Part VI)

D Best Available Control Technology (BACT) Review; Lowest Achievable Emission Rate Review; Maximum Achievable Control Technology (MACT) Review (See Part VII)

E Premises Emissions/Fee Calculations

F Signatory Responsibility Certification

G CGS 22a-6m: Compliance History

Findings:

Attachment Findings

A All HAPs are in compliance with Section 29.

B Modeling report shows that the facility will not cause or contribute significantly to a violation of any State AAQS, federal NAAQS or federal PSD increment.

C Applicant is required to obtain 171 tons of NOx offsets prior to final CP/OP being issued.

### Montville Power LLC **Page 16 of 16**



### NSR Engineering Evaluation Attachment Coversheet **Connecticut Department of Environmental Protection Bureau of Air Management** 

Findings, continued:

Attachment Findings

D BACT has been determined to be the following:

**Pollutant BACT/LAER Compliance Demonstration** PM/PM-10 Dry ESP 0.026 lb/MMBtu Stack test; COMS(10% 1 hour-block)

NOx 0.06 lbs/MMBtu all fuels **(LAER)**
171 tons of emission reduction
credits **(LAER)** RSCR (BACT) Stack test; CEMS(24 hour-block)

SOx Use of inherently low sulfur
fuels 0.025 lbs/MMBtu Stack test; CEMS(3 hour-block)

CO Oxidation catalyst and good combustion practices 0.1 lbs/MMBtu Stack test; CEMS(8 hour-block)

VOC Oxidation catalyst and good combustion practices 0.01 lbs/MMBtu Stack test; CO CEMS as surrogate

NH 3 Slip Complying with emission limit of 18 ppmvd, and optimization of RSCR system Stack test; CEMS (24 hour-block)

E Based on the analysis of alternatives provided by the applicant it has been determined that this project is a suitable method of power generation for this site.

F The permit fee is $15,000.00.

H No past or present violations prevent this permit from being
issued.

### Ms Cynthia Karlic NRG Energy – Montville Power, LLC

P.O. Box 1001 Middletown, CT 06457

Dear Ms Karlic:

This letter is to inform you that the Department of Environmental Protection Bureau of Air Management has completed the evaluation of your application and has made a tentative determination to approve the permit to construct and operate the conversion of Unit 5 located at 74 Lathrop Road, Uncasville, CT to allow 42 MW of biomass firing and retain the peaking ability of 82 MW for up to a 7% capacity factor using either natural gas or ultra low sulfur distillate subject to the following:

(1) Submission of the appropriate permit fee (invoice enclosed) under Section 22a-174-26 of the Regulations of Connecticut State Agencies (RCSA) . Remit payment as directed on the enclosed invoice. The following is a description of the permit fee:

Application No. 200901310 Permit No. 107-0056

Permit to Construct & Operate (per RCSA 22a-174-3a) Premises size: Major

Total Permit Fee: $15,000.00 Minus application fee received: - 750.00 Minus transfer of 2 withdrawn application fees (50%) - 750.00 Amount Owed $13,500.00

(2) Pursuant to RCSA section 22a-174-2a(b) and Sec tion 22a-6h of the Connecticut General Statutes (CGS), publication of the enclosed notice of tent ative determination is required to provide the opportunity for public comment. Within five (5) days of the date of this letter, the notice will be published in the following newspaper:

The Day 47 Eugene O’Neill Drive
New London 06320

### -2-

Cynthia Karlic Gary S. Rose Montville Power, LLC

Under CGS Section 22a-6h the notice is to be published at the applicants' expense. Further processing of the permit is contingent on receipt of the permit f ee and reimbursement for the cost of public notice. In order to avoid delays in the processing of your permit, it is in your best interest to submit this payment promptly.

A tentative determination is not a final permit to construct and operate. The tentative determination starts a 30-day public comment period and affords the public an opportunity to request a public hearing.Construction activities allowed prior to permit issuance are specifically addressed in RCSA Section 22a174-3a(b). You may enter into legally binding contracts and may begin site clearing activities. You are not allowed to begin actual construction specific to your project. This includes excavation, blasting and removal of rock and soil, installing footings, foundations, retaining walls, or permanent storage
structures. To do so would be a violation of the Connecticut Air Regulations and the Federal Clean Air
Act.

Please read the enclosed tentative determination carefully. If you have any comments or questions, please contact Mr. James Grillo by calling (860) 424-4152.

Date Gary S. Rose
Director Engineering and Enforcement Division Bureau of Air Management

GSR:JAG:jad

Enclosure

Certified Mail

### The Honorable Joseph W. Jaskiewicz Mayor Montville Town Hall, 2nd Floor 310 Norwich-New London Tpke. Uncasville, CT 06382

Subject: Connecticut General Statutes (CGS) Section 22a-6h Notice Montville Power, LLC, 74 Lathrop Road, Montville, CT Application No. : 200901310

Dear Mayor Jaskiewicz:

Section 22a-6h of the Connecticut General Statutes requires the Commissioner of the Department of Environmental Protection, pr ior to approving or denying certain permit applications, to publish or cause to be published notice of tentative determination regarding such applications. This Section also requires that “The commissioner shall further give notice of such determination to the chief elected official of the municipality in which the regulated activity is proposed.”

In accordance with this requirement, we are providing to you a copy of the tentative determination notice regarding the above-referenced application.

If you have any questions, please feel free to contact Mr. James Grillo at (860) 424-4152.

Sincerely,

Gary S. Rose
Director Engineering and Enforcement Division Bureau of Air Management

GSR:JAG:jad

Enclosure

# Department of Environmental Protection Bureau of Air Management Request for Publication

Date:
VIA ELECTRONIC MAIL

Laurie Taylor Graystone Group Advertising 2710 North Avenue, Suite 105 Bridgeport, CT 06604 ads@graystoneadv.com
1-800-544-0005

cc: Dennise Goulbourne, DEP

Contact Name: James Grillo Phone: 424-3570 E-mail: james.grillo@ct.gov

Publication Requested Publication Date:

Please make a one-time insertion of the attached pub lic notice in a single column space set solid under Legal Notices in the following newspaper(s):

Connecticut Post Waterbury Republican The Hour
Bristol Press The Middletown Press Norwich Bulletin
The Chronicle The Record-Journal Register Citizen The Day Naugatuck Daily News The Advocate
Greenwich Time The Herald Waterbury American
The Hartford Courant The New Haven Register Journal Inquirer The News-Times

Billing
Purchase Order Number: DEPM1-0000023888

Please note that the Department will not remit paymen t for publication of the attached public notice until copies of the public notice and certifications of the publications are forwarded to the Department. Please address such mailings as follows:

Attn: Dennise Goulbourne, (JAG-4152) Department of Environmental Protection Bureau of Air Management
79 Elm Street Hartford, CT 06106-5127

Payment will occur through Dennise Goulbourne, Fiscal Administrative Officer, Bureau of Air Management, at (860) 424-3026. Please contact he r for further information regarding billing.

### LEGAL NOTICE DEPARTMENT

Dear Sir:

Please make one (1) insertion in a single column space, set solid, under Legal Notices, in the issue of your next paper following the receipt of this letter, of the notice provided below.

Kindly render the invoice in duplicate with two clippings showing the insertion.

_____________________________________________________________________________

MONTVILLE POWER, LLC MONTVILLE, CT

NOTICE OF TENTATIVE DETERMINATION REGARDING A POINT SOURCE

PERMIT

The Department of Environmental Protection hereby gives notice it has made a tentative determination to approve an application submitted by Montville Power, LLC ("the applicant") under section 22a-174 of the Connecticut General Statutes for permit to construct, install, enlarge or establish an air contaminant source or to operate a source regulated under the Clean Air Act Amendments of 1990. Specifically, the applicant proposed a major modification to add biomass firing to their existing 82 MW (Unit 5) boiler to combust biomass at 42 MW and retain the peaking ability of 82 MW for up to a 7% annual capacity factor using either natural gas or
ultra low sulfur distillate oil.

The DEP has tentatively determined that the Lo west Achievable Emission Rate (LAER) for NO
x 

### control shall be 0.06 lbs/MMBtu (heat input) for all fuels. The total emissions reduction offsetrequired is 195 tpy. The applicant is required to purchase 171 tons of approved serious “nonattainment” NO
x 

### emission reduction credits after all internal reduction offsets are considered, to offset the potential 161.9 annual tons of NO
x 

### that may be emitted from Unit 5. The internal reduction offsets, 24.2 tons/year, used in this calculation are the average annual NOx emissions for calendar years 2007 and 2008 for the boiler prior to this modification.

According to the ambient air impact analysis, the proposed facility will not cause or contribute significantly to any violation of a National Am bient Air Quality Standard or Prevention of Significant Deterioration (PSD) increment. The predicted PSD multi-source ambient impacts for nitrogen dioxide (NO 2 

### ), sulfur dioxide (SO 2 

### ), and PM-10 are presented in the table below:

**PARAMETER PSD INCREMENT (**  μ **g/m 3**  **) MAXIMUM IMPACT (** μ **g/m 3**  **)**

**SO 2**  **annual** 20 <1*

**SO 2**  **24-hr average** 91 <5*

**SO 2**  **3-hr average** 512 <25*

**NO 2**  **annual** 25 <1*

**PM-10 annual** 17 1

**PM-10 24-hr** 30 11 

### * NRG Boiler 5 maximum impact below the significant impact level (SIL). No further PSD

modeling required.

### -2-

Legal Notice, continued

The name and address of the permit applicant are: Montville Power, LLC, 74 Lathrop Road, Montville, CT. The proposed activity will take place at: 74 Lathrop Road, Montville, CT. The proposed activity will affect air resources. The application has been assigned SIMS number

200901310 by the Department of Environmental Pr otection Bureau of Air Management. Interested persons may obtain copies of the application and proposed permit from Ms. Cynthia Karlic, NRG Energy, P.O. Box 1001 Middletown, CT 06457; Tel: 860-343-6962. The application, engineering evaluation and proposed permit are available for inspection at the office of the Department of Environmental Protection Bureau of Air Management, 79 Elm Street, 5th floor, Hartford, Connecticut, 06106-5127 fr om 8:30 - 4:30 Monday through Friday.

Interested persons will have thirty (30) days from publication of such notice to submit comments in writing to the Department of Environmental Pr otection, Bureau of Air Management or request a public hearing concerning the Commissioner’s tentative determination to approve the permit application, in accordance with section 22a-3a-5(b) and section 22a-174-2a(c) of the Regulations of Connecticut State Agencies. Comments should be directed to Mr. James Grillo, Bureau of Air Management, Department of Environmental Protection, 79 Elm Street, Hartford, CT 06106-

5127.

### Ms Cynthia Karlic NRG Energy – Montville Power LLC

P.O. Box 1001 Middletown, CT 06457

Dear Ms Karlic:

Enclosed is a certified copy of your original permit to construct and operate the conversion of Unit 5 to allow 42 MW of biomass firing and retain the peaking ability of 82 MW for up to a 7% capacity factor using either natural gas or ultra low sulfur distillate oil at the above location at 74 Lathrop Road, Montville,

CT.

This letter does not relieve you of the responsibility to comply with the requirements of other appropriate Federal, State, and municipal agencies. The permit is not transferable from one permittee to another (without prior written notification), from one location to another, or from one piece of equipment to another. The permit must be posted for easy access at the site of operation.

Permit renewal applications must be filed at least one hundred twenty (120) days prior to the permit expiration date, if applicable. Pursuant to Secti on 22a-174-3a of the Regulations of Connecticut State Agencies, Montville Power LLC must apply for a permit modification/revision in writing if it plans any physical change, change in method of operation, or a ddition to this source which constitutes a modification or revision pursuant to Section 22a-174-1 and 22a-174-2a , respectively. Any such changes should first be
discussed with Mr. James Grillo of the Bureau of Air Management, by calling (860) 424-4152. Such changes shall not commence prior to the issuance of a permit modification.

Sincerely,

Gary S. Rose
Director Engineering & Enforcement Division Bureau of Air Management

GSR:JAG:jad

Enclosure

### Ms. Ida McDonnell Unit Manager Air Permits Program (CAP) U.S. Environmental Protection Agency Region 1 – New England 5 Post Office Square, Suite 100
Mail Code OEP05-2 Boston, Massachusetts 02109-3912

Dear Ms. McDonnell:

Please find enclosed materials related to a new source review permit. The source is identified as:

A. Name of Facility: Montville Power LLC

B. Location: 74 Lathrop Road, Montville, CT

C. Brief Description of Project: Conversion of thei r 82 MW (natural gas or No. 6 oil) Unit 5 boiler to allow 42 MW of biomass firing and retain the peaking ability up to 82 MW for up to a 7% capacity factor using natural gas or ultra low sulfur distillate oil.

D. Source/Premises Size: Major Modification/Major Source

E. Nature of Material Enclosed: application, engineering evaluation and proposed permit.

We understand that EPA requires thirty (30) calendar days to review this package. Should you have any questions, please contact Mr. James Grillo the case engineer at (860) 424-4152.

Sincerely,

Gary S. Rose
Director Engineering and Enforcement Division Bureau of Air Management

GSR:JAG:jad cc: Donald Dahl, EPA Region I

Enclosures

# MEMO

TO: CPPU

FROM: James Grillo, APCE Kiernan Wholean, SAPCE

SUBJECT: Transfer of application fees for Montville Power

On January 17, 2008 Montville Power LLC submitted applications for two LM6000 combustion turbines, 200800125 and 200800126. On 04/15/09 the applicant requested that those applications be withdrawn since they changed their plans for the site which included a major modification to Unit 5, application no.

200901310.

Please transfer 50% of the application fees ($750.00) from the above referenced applications to the current application, 200901310, as part of the permit process fee.

James Grillo, APCE

Kiernan Wholean, SAPCE

JAG:jad

## Montville Power Major Modification, Unit 5

• Currently Unit 5 is a registered 82 MW electrical generating boiler firing No. 6 fuel oil that operates under an RMR (Reliability Must Run) contract with ISO-New England until June 1, 2010 as a peaking unit. After that time it will operate in the Forward Capacity Market.

• Major modification consists of converting to a stoker fired 42 MW biomass (no construction debris or regulated wood fuel) base load boiler with 82 MW peaking capability firing either natural gas or ultra low sulfur distillate oil. The fossil fuel/peaking firing capability will be limited to a 7% annual capacity factor.

• The modification to the plant will use state-of-the-art emissions controls consisting of the following: a new electro-static precipitator (ESP) to control particulate emissions; multi-clones to collect fly ash from the exhaust stream; a new regenerative selective catalytic reduction (RSCR) unit to control NOx emissions; and oxidation catalyst to control CO and VOC emissions along with some organic HAPs emissions.

• The boiler will be subject to the New Source Performance Standard (NSPS) 40 CFR Part 60 Subpart Db once the conversion to fire biomass is complete. Currently this boiler is exempt from NSPS regulation due to its original construction date.

• There will be no co-firing of biomass and fossil fuel except during the transitional period from biomass to fossil fuels. The existing steam turbine will not be modified and no increase in maximum rated capacity is planned for the boiler/steam turbine.

• Biomass fuel will be delivered to the site by local roadways via tractor trailers and screened for oversized material. Any oversized material will be hogged to appropriate fuel size specification and then transferred by conveyor to a storage pile and fed to the boiler by an enclosed conveyor system. No single fugitive particulate point sources require an individual NSR permit.

• All fugitive dust particulate emissions from the fuel/ash handling have been included in the permit.

• Refined modeling/PSD review was performed for PM10/2.5, CO, SO 2 , and NOx. The modeling report determined that the facility would not cause or contribute significantly to a violation of all state and federal ambient air quality regulations.

• Plant will meet all state and federal emissions limitations which will be verified through the use of continuous emissions monitoring and recurring stack testing.

• There has been no public interest concerning the air permit for this source. There was some concern over traffic during the Siting Council hearing. The Siting Council directed the town and applicant to submit another traffic plan that was agreeable to both parties.