## Supporting Documentation for BART Analyses " PSNH Correspondence, December 4, 2009 " PSNHCorrespondence, July 9, 2010 " PSNHCorrespondence, August 16, 2010 " PSNHCorrespondence, December 15, 2010'~~~~Ulrr.".,=



### \ Public Service of New Hampshire December 4, 2009 Mr. Robert R

. Scott, Director Air Resources Division Dept . of Environmental Services 29 Hazen Drive, POBox 95 Concord, NH03302-0095 PSNH Energy Park 780 North Commercial Street, Manchester, NH03101 Public Service Companyof New Hampshire P .O . Boa 330 Manchester, NH

03105-0330 (603) 634-2236 Faa(603)634-2213 macdojm@panh.com The Northeast Utilities System John M . MacDonald Vice President - Generation

Public Service Company of New Hampshire Request forAdditional Informationfor Determination of Best Available Retrofit Technology (BART) for the NH Regional Haze SIP Dear Mr. Scott: In response to your request, dated November 17, 2009, for additional information necessary to finalize the NHDepartment of Environmental Services, Air Resources Division's response to comments received fromthe U .S. Environmental Protection Agency and Federal Land Managers specific to DES' Best Available Retrofit Technology (BART) demonstration, Public Service Company of New

Hampshire is submitting the enclosed information . As you know, PSNHdid not submit written comments specific to DES' BART determination presented at the public hearing onJune 24, 2009, because PSNHwas in agreement with that determination. PSNHis interested in understandingthe basis ofany significant changes to the BART determination and would raise objection to overly stringent BART limits that provide minimal environmental benefit yet increase costs and expose PSNH's generating facilities to permit exceedances during the course ofnormal operation ofthe units. Incremental Cost Estimates of S02 Reductions at Newington Unit NTl In order to estimate incremental costs associated with varying grades of oil, PSNH evaluated historical fuel cost data provided by Platts for the period of 2002 through September 2009. Considering the inevitable inaccuracies in trying to predict future fuel prices, PSNH has calculated incremental cost estimates for illustrative purposes using the more recent historical fuel cost data (2005-2009) . As illustrated on the enclosed spreadsheet, PSNH has estimated the incremental costs, on a dollar per ton basis, of sulfur dioxide reductions at Newington Station, Unit NT1 to be as follows: 2% sulfur content by weight to 1 % sulfur content by weight $1,030 per ton S02 reduced 1 % sulfur content by weight to 0 .7% sulfur content by weight $2,949 per ton S02 reduced 0 .7%sulfur content by weight to 0 .5% sulfur content by weight $7,203 per ton S02 reduced 0 .5%sulfur content by weight to 0 .3% sulfur content by weight $12,957 per ton S02 reduced

086529REV

. 1-09Mr . Robert R . Scott, Director December 4, 2009 Page 2 of 3 Assumntions Used to Produce Estimated Incremental Costs The assumptions used to estimate incremental costs include historical fuel prices, maximum gross heat input rate of Unit NT1, S02emission rates in lb/mmBtu and lb/hr for each grade of fuel, and tons of S02 reduced. Capacity factor ofUnit NT1 is not necessary to calculate incremental costs on adollar per ton reduced basis. The S02emission rates were derived from the sulfur content of the fuel, the heatingvalue of the fuel, and the maximum gross heat input rate ofUnit NTl . The tons of S02 reducedwere calculated using the delta in S02emissions between each fuel type on a Ib/hr basis which was calculated using the S021b/mmBtuemission rate for each grade of fuel and the maximum gross heat input rate of Unit NTl as contained in Newington Station's Title VOperating Permit, TV-OP-054 . Additional Costs Associated with Fuel Storage Upgrades. at Newington Station At the present time, PSNH is hopeful that the current fuel storage and delivery system, including configuration and storage capacity, is adequate to handle varyinggrades of oil if required in the future. As a result, PSNHhas not calculated additional costs associated with fuel storage upgrades. MKUnit #2 Boiler and SCRO ations The SCRhas a temperature permissive that must be met in order for the SCR to be put in service or kept in service. During start-ups, shut-downs, and low load operation of Merrimack Unit #2, the temperature is lower than that permissive temperature and the SCRcannot be operated. As an example, Merrimack Unit 2 typically has 10 to 15 outages per year, in addition to approximately 8 low

load operating periods per year . The timing of these conditions is not predictable and this estimate of occurrences provided reflects historical performance. Examples of low load situations include, but are not limited to: forced and planned outage start ups and shutdowns, loss ofone of any equipment pair where both pieces ofequipment are necessary for full load operation and the loss ofone results in half load operation (such as Forced Draft Fans, Condensate Pumps), loss of the Main Boiler Feed Pump, loss of coal feeders, condenser waterbox cleaning, etc. Any condition which requires the unit be at loads below 230 mw net, causing the temperature to be below the SCRpermissive will result in the SCR not able to be put in service. This load point may increase with the new, more efficient HP/IP turbine. In addition to boiler operations and load conditions that affect SCRoperation, malfunctions of the SCRsystemand/or associated equipment can also affect the operation ofthe SCR . , Malfunctions ofthe SCRsystemand/or associated equipment canresult in partial or complete reduction of SCRperformance. As part of normal service, the SCRcatalyst becomes coated with flyash. Blinding ofthe catalyst with flyash can cause the SCRprocess control settings (often referred to as the setpoint) to have to be increased (less NOx conversion), as the reagent distribution becomes less uniformand asMr. Robert R . Scott, Director December 4, 2009 Page 3 of3 less catalyst is exposed to the flue gas. The SCRis cleaned as needed during outages, and sootblowers are used on line. Reagent injection grid nozzles, being in the flue gas path, can become fouled with deposits. This can affect reagent distribution, compounding the effect ofa fouled catalyst, for example. The reagent injection grid is cleaned, as needed, during outages. Also, reagent delivery disruption canoccur and on-site storage is limited . Also as a catalyst ages, it becomes less reactive. This causes a reduction in abilityfor NOx conversion to take place. This in itself does not typically result in higher NOx emission because the SCR has four layers ofcatalyst, staggered in age. However, it will compound the effect ofa fouled catalyst, for example. The uncontrolled NOx rate at reduced load andduring start ups and shut-downs is typically 1 .0 - 1 .51b NOx/mmBTU

. The uncontrolled NOx rate at normal full load is as high as 2.661b NOx/nunBTU, with an average of 2 .4 1b NOx/mmBTU

. The SCRis unable to performcontinually at its maximum capability due to these concerns. As'a result, PSNHneeds flexibility to operate the SCRbased on current operating conditions. In closing, PSNHwould like to reiterate its opinion that changes to DES' BART determination that result in more stringent emissions limitations create concerns relative to increased costs and decreased operational flexibility . Please contact Laurel L. Brown, Senior Environmental Analyst - Generation, at 634-2331 ifyou would like additional information or would like to meet to discuss the enclosed information further.

John M . MacDonald Vice President-Generation Enclosure73

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### Public $et-hee of New

Hampshire

duly 9, 2010 NH Department ofEnvironmental Services, Air Resourm- Division 29 Ham Drive P©Box 95 Concord, NH p3302-01D95 . r- -+ y {~ ~s ; N tr f! . Michele Roberge Administrator, Permitting and Environmental Health Bureau



### CONFIDENTIAL BUS

Dear Ms. Roberge: 

### S7NFORMATTUN - er 

### A 1?- z4 -T v ~a1^ "t 

# RECEIVED NEW HAMPSHIRE 

## 'JUL 16 2010 Public Service of New

Hampshire AIR RESQUR.tES iJiVt$10N Best Available Retrofit Technolagy {'BART}. Response to Request for Additional lnfortnatitin

As requested, PSNH provides thefollowing information to support the Merrimack Unit #2 (M1C2) NOx limits and the Newington (N71) fuel oil sulfur content for New Hampshire's Regional Haze , SIP. We are providingthis information as confidential business information since it contains various operating scenarios and financial cws which arecompetitively sensitive in nature and could be harmful if disolosed. Merrimack Station Unit #2 : Merrirnack Station was the first investor owned utility in the nation to install an SCR to achieve NOx reductions. Given the operation of the SCR, it is PSNH's - position that maintaining operational flexibility is a critical priority in order to enaure continued and cost-effective compliance while simultaneously achieving significant reductions in NOx emissions. The following information summarizes the primary drivers and the associated costs that would be incurred in ensuring attainment of NOx emissions rates lower than the currerrt NOx emission limits set in the NH Ft4ional Haze SIP I . OperatingTemperatur6 of SCR As previously provided, the SCR has a temperature . perrnussive that must be met in order for the SCR to be put in service or kept in service. -During start-ups, shut-downs, and row load operation of Merrimack Unit #2, the temperature is lower than that permissive temperature and the SCR cannot be operated. For example, Irrlerrimack Unit 2typically has 10to 15 outages per year and approximately $ low

load operations per year . During these events, SCR operating temperatures are less than the permissive tempeirature rendering the SCR inoperable. The timing of these events is not predictable; the estimate of occurrences provided reflects historical performance. Examples o£low

load situations include, but are not linitted to, the following: + Forced and planuyed outags start ups and shutdowns; 

### PsNHEnergy Pw* 700 North CornmerciaT Snr.ci, Manchester, M-1 08909 PubLP

Se7YtC4 Company of Now fkmp4him P .C . Box 33a hiame-batcr . NE 03105-W30 (603) 689-4000 nrovw .psn}s,oaars The N+n't1hease UtWties System

1786561 REV

. 11 .09Ms. Michele Itoberge, Admitlistratcir

July 7, 2010 

### Page 2 of 7 Loss of one of any equipment 

### the loss ofone results in half I~a~erat;on (suc~ pumps) ; e Loss of the main boiler feed PUMP" necessary for full load operation and forced drafl fans, condensate " Loss of coal feeders, condenser waterbvx cleaning, cstc. ; and " Anycondition which results in the flue gas temperatures to be below the SCRpercnissivs temperaturewill result in the SCPL not able to be put in service. 2 . Malfunction and Fouling ofthe SCR and/or Associated Equipment in addition to boiler operations and load conditions that affect SCRoperation, rrta.lfunctions of the SCRsystemand/or associated. equipment can also affect the operation of the SCR . Malfunctions of the SCRsystemand/or assaciated equipment can result in partial or complete reduction of SCRperformance

. Also as part of normal service, the SCRperformance deg,rades overtime. One reason this occurs is dueto blinding of thecatalyst with fly ash, This condition will cause the SCRprocess control settings to compensate by increasing SCRloadingto maintain the set point . This is necessary because the reagent distrlbution becomes less uniformas less surface area ofthe catalyst is exposed to theflue gas. To matnage this condition fromdeveloping to the point that a maintenance outage is ncce,ssary, the SCR is cleaned on-line utilizing soot blowers and cleaned during outages, as needed. Increased SCR loadingwill lead to more frequent maintenance outages. Reagent injection grid nozzles aredirectly exposed to the flue. gas and become fouled overtime. This can aff+ect reagent distribution, oompottndittg theeffect ofafouled catalyst. The rea,gent in3ec0oa grid is cleaned, as needed, during outages. Alsoas catalyst ages, it becornes less reactive. This causes a reduction inability for NOx conversion to take place . Thus ite itself does not typically result in higher NChx emissions because the SCRhas four layers ofcatalyst, intentionally staggered in age .- However, it will compound the~efhct ofafbuled catalyst and am result in the SCRbeing unable to perform . continually at its maximum capability. As a resuli, PSNH needs flexibility to operate the SCR based on current operating conditions. Cu=tly the SCEL avezages greater than 86% efficiency. Theuncontrolled NOx rate at normal full load ,is us high. ~ 2,66 l~, NOx}mm'3"1'CJ, with an average of 2.4 Ib hdOxltt~mBT(J . The uncontrolled t+l{3x rate at reduced load and during start ups and shut-downs is typically 1 .©-1 .5 lb NClxfmmBTCJ . With:these short-termchallenging operational conditions, PSN1=I's~grestest ooneexn is ensuring consistent compliance. We have reviewed historical daf* andconcluded that start-ups and shut downs can significantly impact both a calendar month and a rolling 30-day average-emission rntwe bj+ up to 0

.04 lb NOx1aYrnBTlI . -If there is more than 1 outage during the averaging period, the irtipsyot to the average emission rats could be as high as D .#t$ lb N(7adrnmBTU

. To allowfor this potential operating occutreneo, Merrimack Station would need to operate to maintain u much lower average NOx rate. Reviewing the historical monthly averages, this leaves little margin for typical operating fluctuations in NOxcontrols. For example, ifa unit is offfor a longerperiod of time, thereare less valid operating days available to he included in average rate. 'I'bis analysis is particularly int~eresting, because in this specific scxnario, the total tons ofemissions are less than full load operation for tlmsame averaging period, but could have a~high eznission rate. An extremeexample ofthis soenario was observed in August 2009 when the monthly average emission raw

was 4.813 ib NOzclmmB'i'U and yet total emissions for that month were

### Ms. Michele Roberge, Administrator

July 7, 2010 Page 3 of ? approximately 1 ton. This was primarily duethe unit operating only a short amount oftime in that Month. 3 : Potential Costs Associated with Proposed Reduction in NNemission rata Merrimack Station will need to consider a number of additional compliance efforts if not provided the necessary flexibility to deal with short-termevents as described above and the operational restrictions of the SCR . Each has an additional cost as outlined below . Therewill be increased mail3tenasxee costs to maintain peak NC3x reduction capability. For example, air heater-cleanings will be required more frequently because ofincreased loading of the SCR . This scenario results in additional maintenance costs and replacement power costs associated with the required outages. Maintenance (Cleaning) Costs: $30,000to $100,000per cleaning Replacement Power Costa: Thetable below uses an assumption of - $3Ulmwhr difference between thecosk of Merrimack Station andthe market cost. This number can vary grWlydepending on energy market prices. Duration Of TUpliteement Power Number of outages TOW Cost per Year C1sanEn IUuta e Cost per Ontalte p er year 

### Short Qdwl $720,000 1 MD,0ao

, 2 S1,44Q,QQ4 3 $2.1bf1>t}4[} 4 $2 8 0W Mid (4.5 

### days) $1,100,000 i _ - ----- 

### -si,loo,aoa ' $2,200,000 3 S3,34Q,44(} Long (6days) 1 $1,400,000 

### s28o0,oaQ Ifair heater washings were rouitnely necessary to comply with dstep change 'in the NOx rate, the c,ost parton ofNQx reduction would be extremely costly, as illustrated below . This cost can increase greatly ifan air heater cleaning was compleW during a high priced market, tmission Rate 1VOx tow emitted per Lb N{)xlEnm$T!1 ear Incramental tens peryaar Incremental tons per day 0 .37 56204 0 .34 5171 .99 456 .35 1 .25 Duration of Cleanio 0uta e Replaeement Power Cusf p er Outa Incremental tars per year Cost per Ton Short (3days) $720,000 456 .35 $4578 Mid (4 .5daprs) $1,14D,©00 456,35 $2,430 Long (6days) $1,400.40D 456 .35 $3,06$Ms . Michele Roberge, Administrator

July 7, 2010 

### Page 4 of 7 Examples of other compliance measures that would be necessary include accelerating the catalyst replacement in the SCRmanagement plan. Currently, one layer 4f catalyst is exchanged every 2 years, To revise this plan by exchanging one layer every year would result in a project expelue of approximately $1 million every other year. lricreasing the frequency of catalyst repl .acestnent would result in approximately $12 million over the period 2013 thru 2425. This revised replacement plan would not likely result in additional total reduced tons ofNOx for the year, but rather hedp manage the brief periodic increased emission rates associated with the events described above

. 

### It should be reiterated that these compliance cneasures-are focused solely on the shortasr duration events that typically occur at lower loads with less beat input and for a discreet period of tirne.- and thus do not resal# in the emission n#'a significant amount NOx emissions. For example, the flexibility of partial load operation during high demand paiods is important to theelectrical reliability of thegrid and can significantly protect customers fromhigh energy costs during these peak events. It would not be in the public interest to require the unit to come off line since such action would be extremely, costly to both reliability and to customers. Ahalf day ofnn operation when energy prices areover $l0Unawh will be $25(l,000, $35t},004 or greater; acost that would yield a NOx reduction of only approximately 10 -15tans. , This discussion demonstrates that the implementation of a caLender month and roiling 34 day tblmmbtu NOx emission rate can mutt in significant cost to our customers with little environmental benefit . To avoid permit exaeedancess due to a short-termNOx rate excursion, would require runningthe SCRharder, more frequent ttir heater cleaning, extended outages, and forced outages.' . it 1a.cement wercost associated with outages

, Cost deltawith the

Market Total cost bfOutage

--forcustomers Cost pet' Ton

_ 1 day $30 $239,U40 $15,936 $0 $318,720 $21,249 S50- $398, 400 $26 , 560 

### 2 days $30 $478,080 $15,936 S40 S637,440 $21,248 

### 1$50 $796,840 $26,550 *assurnes saving of L5.tons per day .- As you are aware, Merrimack Station has aggressively reduced NOxernisslons for the past 15 years, Mw

total annual emissions reflect that laucla.ble esffart . Goingforward, Merc'ima4ic Station anticipabes continuing that ef'fort, while maximizing customer value and providing reliable, affordabte power, but to do that sucoessfuily, we do requ'srn operational flexibility. It is critical to understand that such operational flexibility will ensure consistent compliance with the monthly avezage emission rate while not significatttly increasing total NOx emissions. Xe,_ winmvn Station- additional fuel oil i.nforrnetion In your June 15, 2010e,may"l, you also.requested information regarding Newington Station's current oil stacks, storage capacity, fuel usage rates, and operational considerations and costsMs. Michele Rc}berge, AdrriinistratDr

July 7, 2010 

### Page 5 of '7 associated with switching to lower sulfur fuels required by the NHRegional Haze SIP . That information is provided below . Please describe the current oil stocks (type andquantity) andstoragecapabilities. Newington Station has the capacity to store approximately 732,504 barrels t31 million gallons) of fuel oil in four separate Aboveground storage tanks (identified as NT-1, TNT-2, ''~2, SR-2, and SR-3) . Curt+ently, these four tanks contairj approximately 485,000barrels (20 million gallons) of No. 6 fuel oil with an average sulfur concentration of approximately 1°fa. ' How many hours ofoperation wouldthis supply at`'current usage rates? What are the ,rates 1hal this ostimate is basedon? Due to various economic conditions, including the rising cost 4ftdo. b fuel oil, lower natural gas~ prioes and electric derrxautd, Newingbotn Station has burmd only a limited volume of oil in the past couple years. Current conditions are not expeoted to change considerably in the short, term, therefore, Newington does not anticipate consuming a significantvolume ofoil in the next couple ofyears . , . It is difficult to assess how long it would take to deplete this fuel oil inventory since fuel oil usage is dependent on market conditions and the demand fbr electricity. Newington 8tation will choose the fuel or blend-oi`fuel-(~ozly nattaral-gas ;~ar-natrna[~as-arrd-oi-l-rbased oct°tlte~d+esired-elecirical--- .. output and the cost offuel . As youare e.ware, Newington Station will use the most cost effective fuel .to maintain its electric costs for the customer. - In an effort to understand how this inventory relates to future operating conditions, PSNI-1 has looked at different operating scenarios to estimate the length of time it maytake to deplete this inventory. The gcenaitios include-dil :'ferent~raperating loads, a fuel mix of 75% natural gas and 25% fuel oil, and an opeeating capacity factor of 5°l0 (see table below) . Although, PSNJi can not reliably predictwith anycertainty how Newington Station twill operate in the next couple years, for purposes of this eualuatiott, PSN1a has assumed an average, output level of 15(l MW with a heat rate of 11,750 Btu/kWh, 75°fo natural gasl25°l0 oil blend} and acapacity factor of 5% . Based on current fuel oil inventory levels, and the scenario presented abovc, Newington Station would -deplete its existing fuel supply in 16years: ~ .. ~ . . . . . , , . MW BtadklNh t3tuPgaT OH Capactty Factor 9~ . Bsrlyr 7596 gaelT6iL all smyf R ~ 9 9tt411

of current tmrsnto rs 400 10,793 153,848 5 292 .046 5 73161 T

. " ' ~r ~ .~~,-i .~ .qi p 9X C rl 777777. _ h 104 1 196p 153846 5 93,85') 2S488 21 _ 60 16,56t! t53 46 5 67,352 18,SSB 29 Nae! Rasumhg answougs output levsl of 780 MW wKh a heal telsof 11,76D BUM, a 745XhZ~Y+~aslal aie~ra, snda capsdlyrectarof s1i, the lwtrsnl hrvenloty+waulC be 4eplelwa.ln 16yaure

. Tlwls seealatlok Mem"ton SIsUcu'e best ssllmais tosss8an aKrendopera8na~ 18slary

. What tire the specific operational considerations in switching to (1.3°o S oil that do or do not make itfeasible andcostly?

### Ms. Michele Robcrge, Administrator

July 7, 2010 Page 6 of7 pSN14 understands that tha Regional Ham SIP will rcquire *Newington Station tu burn 0 .5%or 0.3 lo sulfur oil as part of its compliance aatrategy as earJyas 20 13. In order~to prepare for this requirement, Newington Station would need to have the available capacity to store the lower sulfur nil . Due to a variety of factors that affect theavailability and cost of natural gas, l'SNH believes it would be necessary to empty one ofthe larger bulk fuel oil storage tanks, at a rninirnum, to provide the storage capacity ofthe lower sulfur fuel . Our largest tanks (N1'1 and NT-2) currently contain approximately 160,000 barrels each of fuel oil . fiased an the likely operating scenario presented above, it -will take more than S years to empty one of die larger taitics. In this scenario, Newington would either need to operate and utilize the on'-hand fuel or sell some of its current inventory ifan acceptable pmcess could be identified. !t is difficult to estimate what thecost to PSNH would be if this were re+quired, since tlie value of this oil in 3 years is unknown. 

### 1'SNHcurrently knows af no way other than consuming oil in the unit to disposeldeplete our curre .nt inventory. Although offloading oil frorn the tanks to a barge or ship is beirig oonsiEtlened, 1\iewington's oil terminal was designed to aocelat deliveries of oil fromfuel vessels and was not designed to load vessels fromthe oil tanks. lwlewington Station also does not have the capability for loading trucks frotn the oil tanks . Any risk to.personnel safrty or the environment would need to be fully eliminated to consider a trausfet' of oil to a vessel or truck_ Theraefore,, at this point, it is assumed thstWewiWn Station would be required to burn . the oil in the unit at a potential incremental cost to NH eustomers. Consistent with the numbers above, to burn 160,000 barrels of oil toempty one ofthe larger tanks, the unit would have to operate an equivalent of 24 hours/day for approximately 10 days at 400MWs. Also, as stated above, due to coonomic conditions, hfewington Station has been reserved to protect customers fromhigh priced market excursions. Ifwe assume consumption of the inventory ofoil is required, then it will be necessary forH'ewangton to operate at rates higher dian market rates. In this case, based on-an increrrt®ntal cost of $8{1 per MWH, the total cost tocustomers will- be approximately $8 million. This is a significant cost to customers which has no associated environmental benefit. 81mdiag, this higher sulfur fuel with lower sulfur fuel or natural gas over time is a more cost effective option and will not result is greater emissions as compared to a targeted depletion effort described in theabove scenario . Although it is possible to consider the depletion of current fuel oil inventories by blendingwith natural gas, natural gas is not always wailable and- Could not be relied upon as a sole compliance option. W%at arethe estimated casts ofmaking theswitak- both capitai andoperating costs? As presented in our car]ier Deoernber 4, .20491etter, the cost to FSNN in going froma 1 °o sulfur oil to a Q .5°Yo sulfur oil could be as higi as $42/bbl (based on fiuel oil prioes from 2005-20t19) . Similarly, the cost to PSNH in going fromY4/ sutfur oil to 0 .3°lo sulfur oil could be as high as $51Ibb1 . Using the same operating scenario presented above, t'his equates to an additional cost to PSNH customers of $1 .2 miYlkonfy~ for the use 0 .59r' o sulfur fuel and $1 .5 million/year for the use 0.3%

.

### Ms. Michele Roberge, Administrator

July 7, 2010 Page 7.of 7 . PSNHwould be happy to meet with you and your staffto discu&s the information provided above. If you -have questions or require additional information, please contact me at 63A--244U or Sheila Burke at 634-2512, . 

### Sincerely, Elizabeth H

. Till&son Teohnr+cal Business Manager - Generation 

### c+c: ' Sheila Burke, Generation Staff Tara Otscm, Newau.gton StationAugust 16,2010

¢1c CONFIDE SINEI SS INFORMATION 0 (,~f'y~ public Service ofTdewHampshire

13est Available Retrofit Technology (BART) J' Response to Request . for Additional Information

SUPPLEMENTAL INFORMATIONto PS1N1-I's July 16 Lotter. Response to Request for Additional Information re: BART As requested, PSNH provides the fQllowing information to support the Merrimaclc Unit #2 (MK2) Ndx limits for New

fSamgshire's Regional Haze SIP. We are providing this inforniation as ooni " identiaE business information since it contains various operating scenarios and financial costs whiah arecompetitively sensitive in nature and could bs harmful ifdiselosed. 1vlereimack Station Unit #2: Merritnack Station was the first investor ownod utility in the nation to install an SCRto achieve . NChc reductions . Given the operation ofthe SCR, it is PSWs position that maintaining operational flexibility is a critical priority in order to ensure continued and costeffective compliance while simultaneously achieving significant reductions in NOac emissions. The following infosmation summarizes the primary drivers behind the increased costs that would be incurred in ensuring attainment ofNOx emissions rates lower than the currentNOx emission lirnits set in the NH Regional Haze SIP . I- Operational Impacti ; Based on historical data R+iK2typically has 10 to 15 outages peryear andapproximately $ low load operations per year . During these events, SCRoperating temperatures are roduced and in some instances below

the SCRpermissive ternperature limit. The SCRtemperature permissive must be met in orderfor the SCRto be put in service or kept in service . During start-ups, shutdowns, and partial load operation thetemperature, could be lower than the parmissive temperature and the SCRcannot be operated. In most cases the timing offhese events is not predictable . Exampies oflow

load situations include, but are not limited to, the following: " Forced and planned outage start ups and shutdowns; " Loss of one ofany equipment pair. Both pieces are neoesaary for full load operation and the loss of one results in half load operation (such as forced draftfins, condensate pumps) ; . " Loss ofthe main boiler feed pump; - + Loss of coal feeders, condsnser waterbox cleaning, eta. ; and " Anycondition whicii results in the flue gas temperatures to be below the SCRpermissive t+smparalure will result in the-SCR not able to be put in sarvioe . A mom stringent limit could.result in the unnecessary shutdown of the unit rather than Operating at partial load, An example ofthis scenario has occurred in the past when a critical pump failed which nostricted full toad operation. While the pump was repaired the unit remained operating

### Supplemental Information to July 16 Response to R+eqt:iest far Additional Information

August 16, 2010 Page 2 of 7 but at a reduced capacity, the duration of this event was approximately 240hours. 1'SNH's custarners received significant benefit from-this Partial load Operation. Replacement power casts assaeiatod with this type of event areshown in theTable 1 . . Replacement Power Costs: The table below uses, an assumption of$3fl/mwhr difference between the cost-of MKZ and the market oost . This number can vary greatly depending on energy market pricos.

Table la. Cost Associated with De-rate F10 ' ility at 0 .37 lbJMMBtu I Assumes 4.64tans r hr ' Duration of De-Rate 0e-rate

. capacity Remaining Avoided

Capacity Replacement Onlitis PowerCost Cast Per eon 

## 240 hr 132 MW 200MW S1 ,440,000 10e hr 1,2 MW 20a Mw $ 600 ,000 1 so 50 hr 132 MW 200 Mw S 300,000 $0 Table ia. CostAssociated with limited De-rate Flexibility at 0.34 IbNMBtu Assumes 0.59tan er hr Duradon of DoRsta . De-rate Capadty ----

Remaining capacity Online Un-avataiect

Replacement PowerCost Cost per ton 244hr 132 MW 2{7OMtiN $1,440 QOD 310169 100hr 232 MW 200 MW $ !00 OOa St 169 50hr 132 MW 200, MW~_ T 300 , 000 1 Aia.169 I TL}e opportunity fur partial load oporation during high. demand periods would be even more costly to both reliability and to customers. The example mentioned above resultod in a long duration of partial load operation but it is important to mote that during periods of high ettergy prices a . much shor6er event couldalso have significant cost. For example ; assurning $$100per MWh market price, operating at 2atlMVlr partial load far a period of 12-hours would avoid $240,000 of replacement power cost During this period a NC3x reduction of approximately T tons would be realized which equates to $34,004 per ton NCIx. Undersome of these scenarios "le,l load operation would be eliminated to ensure ~catmistent compliance with the proposed NOx limit reduction . 2 -- Maiate_rrance Impaats PS1wTH's highest priority is ensuring carnplzs.nce-with all emission limits. PSNHhas reviewed historical data and 'concluded that start-ups, shut downs pattial load aperatittg conditions and upsets can significantly impact a calendar month averageemission rate, To account for tluwe evemis FSN'f3operates I~TC7x control equipment to maintain aht4x emission rate of approximately 0 .25 Whwl$tu ca.leardar month average . In order to ensure complimce with the 15.4 tonlday limit or the equivalent 0

.371bA4MBtuemissiatti rate, pSNHtargets a{}.15 lb{%CM8tu difference between the average N4x emission rate andthe specific limit. Further limitations would impact operation and increase incremental maintenanceandcapital -cost. in addition to boiler operation and load conditions that affect SCRoperation, malfunctions of the SCRsystemand/or associated equipment canalso affect the operation ofthe SCR . MaMrncticrns

### Supplemental Information to July 16 Response to Request for Additional Information

August 16, 2l}10 

### Page 3 of 7 of the SCRsystemand/or associated equipment can result in partial or complete reduction of SCR performance . Also, as part ofnormal service, the SCR performance degrades overtime. One reason this occurs is due to blinding of the catalyst with fly ash. This condition will cause the SCRprocess control settings to compensate by increasing SCR loading to maintain the set point This is necessary because the reagent distribution becomes less, uniformas less -surface arM of the catalyst is exposed to the flue gas. To manage this condition fromdeveloping to the point that a maintenance outage is necessary, the SCRis cleaned on-line utilizing soot blowers and oleaned during r,utagcs, as -needed. Increased SCR loading could leadjo more frequent maintenance outages. It is anticipated that a minimum of three additional SCRcleanings and sir beater washes would be necessary to maintain compliance with the +4.34 Ib1MMHtu proposed NOx limit. Cleanings are expected cost between $30,(?ofi and $10f?,OOC? as noted belowin item3, Replacement power costs associated with the necessary maintenance outages are also described in item3 be14w

. Additionally, reagent iqjection grid nozzles amdirectly exposed to 3he flue gas and become fbuled over time. This can affect reagcnt distribution, compounding the effect ofblinded c .axatyst. The reag=t injection grid is cl=iod, as needed, during outages. Alsoas catalyst ages, it becomes less reactive. This causes a reducdon in ability for NOx conversion to take place. This in itself does not typically result in higlter N(7x ernissuans because the SCR has four layers ofcatalyst, inmentionslly staggered in age. However, increased loading ofthe SCRcatalyst would be necessary to maintain compliance with the proposed reduction in NOx limit and accelerate catalyst degradation . For examplc, the SCR is unuble to performcontinually at its maximum capability. As a rasult; PSNK needs flexibility to operate the SCR based on current operating conditions. Currently the SCRaverages greater than 86~fa effrciency. Each catalyst layer hes an anticipated functional In of 8 years- and each layer is staggecod in age to accommodate replacing one layer every 24 --months, Further T+1C}x limitation would increase loading ofthe SCRand could result in accelerated caftlyst degradation requiring premature repiar,ernent. This would result in a lass of investment. Even if minor catalyst degradation occurred reducing the catalyst useful life -from8 years to 7.5 years the replacement schedule would need to be adjusted. The change in replacement schedule is neoassary because cataJyst replacement projects must coincide with MK2's overhaul schedule which is on a.12-month cyale. PSNHwould incur a loss of investment of approximately $143,000 annually due to the early replacement. It is also irnportent to note that the revised replacement plan would result in minimal reductions to the total reduced tons of Nt}x for the year, but rather be put in place tea avoid the periodic increased emission rates at the end of the catalyst life. As shown below in Table 2, PBNHbelieves minirnal catalyst replacenzent and maintenance cost are associated with the 0.371btNIIvtBtu rates provided certain exceptions for start-up and sbutdown and malfunctions.

### Suplalemeu.t" atl Information to July 16 Response to Request for Additional Enformation August 16, 2014 Page 4of 7 Table 2. laerem ettal Maintenance and Capital Cost Emimion Calendar Annual Increase Predicted Limit Month Loea of Maintenanm Incremental 

### (IbtNXMBtut) GWtral Investment {Cost ofAir cost

Target ofSCR heater and (lb(NiN48tu} Catalyst SCR 

## 0 .37 0

.22 $0 034 0

.19 s)43,000 I $195,000 1 $338*000----~ 3 -Replacement Pov~rer Ccu;tg associated with the roposeid Rednctifltt ,~ .n NOx Emission Rate Merritnack Station will need to consider a number ofadditional complisuce O :Ffotts if not provided the necessary flexibility to deal with short-termevents as described above and the operational, restrictions ofthe SCR . Each has an additional coat as outlined below . 'There will be incraand maintenance oosts to maintain peak NUx redwticm oambility. For example, air heam

and SCRclo$nings will be required more frequently became of increased loading ofthe SCR

. This results in additional maintenance costs and replacement power costs associated with the required outages. It is anticipated that at least one additional-4.5 day (mid) maiaiastxance outage would be necessary to maintain compliance wlth the 0 .34 lbMMBtu proposed limit . In addition to the maintenance outage additional oleaning will be completed as a proactivo measure during ;forced outages resulting in delayed start-ups. Outage duration is from time, offline until the unit is phand. ifair heater washing were aompleftd #a comply with a. step change in the NOc rate as shown below, the coat pea ton of MOx reduction would be ex#re=ly costly. Again this number can increase greatly ifan air heator cleaning was completed during a higb priced market. Table a. ratakiul am

ialan s 8760 hrs Emission Rate Lb NOxIrnsmBTU 1hIQx tons em[tftd per year Inc,retnental raduction in ,j ;gibeittlAl .ernlssions tons

ear 0,37 5628.34 0 0 .34 3171 .99 ~ +456_ 

### Maintenance (Cle*Wng) Goafrs .: $3t?,0{t0 to $100,000 per cleaning Replacement Power Costs: The table belowuses an assumption of$30trnwhr , difference between the cost of )1M and the market cost: This number can Vary greatly depending on energy market prices. . . . "

### Supplemental Infornaation to July 16 Response to Request for Additional 111forination

August 16, 2010 Page 5 of 7

Table S. [ of 0,34 UVMMBtu Limit Duratlan of aeanin __.Replecemant Power Cosi p er o e Short 3 sL 572040Q Mid 4 .3 da ~I l+b(~ 000 L O d $16 ,02201. 0-00 

### It shvuId be reiterated that these compliance measures are fccused solely on the shorter duration events that typically occur at lower toads with less hod input and for a discreet period oftime thus do not result in the emission of s significant amount of Nflx emissions. To meet the proposed rates of0.34 lb N1QxlJti+IMBtu, under the conditions re6renced above, PSNhi may be forced to shutdown for air heatarlSCIt cleaning and also may be frmoed to shutdown rather than operate at partial load, Each ofthesc aforementioned s=narios has significant cost as described above. Also, with out exceptions for short termoperational conditions additional incrmnental costs may be incurred when considering a calendar month averaging period. PSNH may be forced to delay start-up to maintain a 4.34 IbJMMBtu calendar month average_ It is importaut to note that st=- up shutdowns, and partial load apersting scenarios may bias a lbJIvIM8tu rate but typfcal result in lowtonnage ernission total . To rnandge for this situation it may be necessary for PSl`IH to adjust the current operating strategy by delaying statt-ups or to prevent a short operating periods during the calendar montb, Table 6., Wow illustrates the potential cost with delaying aai outage start-up. oost assmieted with !~d start-up . Table b. Replacement power_

Cost cleft with the 

### Total cost of Outage _Cost per Market for customers- Ton * I day $3{3 -- $239,444 $15,936 $40 $318,720 $21,248 $5ta $399, 00 $2,6560 2 days $30 $478,084. $31,872 $40 $637,440 $42,496 

### $50 $796,00 $53 , 120 *assumes saving of XS tons per dayo,` n GJ

en o M

. ;~ ~r~ 4 ~ r~+ 4o

.~ p, 79 h a 

## c° ;

~(yy 

### 8

Q yl~ [~ . ~I ti~ ~ ~ (] f~~{ ~I

VJ j3 :3 -~

" ,~y V1 H " ~J ,`y ~

`- -q ~ T Q ~r ~ [ .j ~I . " ~

~ ; _ '~ ~y S'! O_4 tiw . $ ~ rr . "+' ~ S? 4

Q N b W

### This analysis demonstrates that the implementation of a 0.34 16lIv'IMBtu or more sfiriiaMt mte

will result in signifieant cost to our customers with little environmental benefit. Uis is true because a lbIMMBtu rate oould result in running the SCR harder, more frequent air heater cleaning,, extended outages, and forced outages, and limit partial load operation . FSNHwould be happy to meet with you and your staffto discuss the information provided above. Ifyou [lave questions orirequire additional ickrmation, please contact Lynn Tillotson at b34-2440or Sheila Burke at 634-2512. cc: Elizabeth H

. Tillotson, TBt,rI, Generation Staff Sheila Bucke, Gencratioin Staff Tara Olson, Afewington Station1'`~S,SMu,3

A S

- F` : pli~ltC ~ePV~Ce of New lliamqahire l+a

December 15, 2410 Robert Scott Director NH Department of Environmental Services, Air Resources Division 29 Hazen Drive POBox 95 Concord, NH03302-0095 P5Jti"H Energy Park 7$0 North Commercial Street . Manchester, N7-1 03101 Public Service Company of NewHampshire P.O . Box 330 Manchester, NH 03105-0330 (603)6b9-4000 www, psnh.com The Northeast UtilidesSystem

Public Service of New Hampshire Best Available Retrofit Technology (BART) Response to Request for Additional Information Dear Mr . Scott : As requested in your December 8, 2010 letter, PSNH provides the following additional information to support the Merrimack Unit #2 (MK2) NOx limits for New Hampshire's Regional Haze SIP . Merrimack Station Unit #2: Merrimack Station was the first investor owned utility in the nation to install an SCRto achieve NOx reductions. Given the operation ofthe SCR, it is PSNH's position that maintaining operational flexibility is a critical priority in order to ensure continued and cost-effective compliance while simultaneously achieving significant reductions in NOx emissions. The following information summarizes the primary drivers behind the increased costs that would be incurred in ensuring attainment of NOx emissions rates lower than the current NOx emission limits set in the NH Regional Haze SIP. This submittal will analyze the 0.30 lb1MMBtu emission rate averaged on a 3{l-day rolling basis as well as the impact of a more stringent limit. A 30-day rolling average is defined as the arithmetic average ofall hourly rates for the current boiler operating day and the previous 29 boiler operating day' . This definition is consistent with November 22, 2410comments provided by EPA pertaining to the draft rule.

~ Badleroperatri3g dayfor units constructed, reconstructed, or modified on or before February 28, 2005, means a 24-hour period during which fossil fuel is combusted in a steam-generating unit for the entire 24 hours. (40CFR 60Subpart De)

066161 REV. 11-09

### Mr . Robert Scott, Director

December 15, 21110 Page 2 of 7 The summary of theanalysis is provided in the following table, all supporting calculations and basis for this determination are detailed in the items below . 

### Summary of Analysis i Emission Limit IblARMBtu Incremental reduction

in Potential tons per ear, Predicted Incremental

Cost Increase $! Cost per ton ~ 0 .37 0 $O s0 0 .30 1,065 $880 , 000 $826 0,25-0 .30 380 $2,888,400 S7 , 600 

### 1--O pemdonal Impacts Based on historical data NM typically has 14 to 15 outages per year and approximately 8 low load operations per year . During these events, SCRoperating temperatures are reduced and in some instances below

the SCRpermissive temperature limit. The SCRtemperature permissive must be met in order far the SCRto be put in service or kept in servioe. During start-ups, shutdawns, and partial load operation the temperature could be lower than the permissive temperature and the SCRcannot be operated. Examples of low

load situations include, but are not limited to, the following: " Forced and planned outage start ups and shutdowns; " Loss of one of any equipment pair . Both pieces are necessary forfull load operation and the loss ofoneresults in half load operation (suchas forced draft fans, condensate pumps) ; " Loss of the main boiler feed pump ; " Loss of coal feeders, condenser waterbox cleaning, etc . ; and " Anycondition which results in the flue gas temperatures to be below the SCRpermissive temperature will result in the SCRnot able to be put in service. The ability to manage these events is beneficial to ourcustomers. Adequate flexibility allows the high cost ofreplacement power to be minimized. Limiting operational flexibility could result in the unnecessary shutdown of the unit rather than operating at partial load. Tables I a . and 1 b. below demonstrate the replacement power cast associated with a 0 .30 lbIMMBtu, 30-day rolling average emission rate. The opportunity for partial load operation during high demand periods would be even morevaluable to both reliability and to customers.

2 Incremental reduction ofPotential emissions is the calculated mean ofthe 0.25-0.3t? range.

### Mr. Robert Scott, Director

December 15, 2010 Page 3 of? Replacement Power Costs: The table belowuses an assumption of $301rnwhr difference between the cost of M 22and the market cost. Table la. Cast Associated with De-rate Fiexibility at 0 .37 lb1MMl3tu Assum es 0 .64 tons r hr '- T Duratjoln of De*-R= De-rate Remaining Avoided 7 7 capacity Capacity Replacement Online Power Cost 240hr 132 MW 200 MW $1,440,000 I i 00hr 132 Mw 200 MW $600,000 50hr ~ 132 Mw ~ 200 Mw $300,000

__ Table 1b. Cost Associated with limited De-rate Flexibility at O . -TO-7 IblMMBtu Assumes 0

.51 ton per hr -

. ,. .x , Duration of De- De-rate Remaining Un-avoided Rate Capacity Capacity Replacement Online Power Cost 240hr _ 132 Mw 204 Mw s1,44(} 000

, , ;, . . .f

. . .

7

. _ ,J Duration of De- De-rate Remaining Avoided Rate Capacity Capacity Replacement Online Power Cost 100 hr 132MW 200 MW $600,000 50 Fir 132MW 2W MW $300,000 Thetable is based on a steady state NOx emission rate of d?.22 lb/NIMBtu and a N4x emission rate of0 .81bJ1v1MBtu during partial load operation. The maximumnumber of days MK2can operate in a partial load is 4 .2 days (1©0 hrs) when considering a 0 .3016J1NMBtu 30-day rolling emission limit. It should be noted previous submittals did not consider the rolling averaging method, because the existing Data Acquisition and Handling System(DAHS) is not configured for this averaging period. Based on EPAcomments ofthe proposed Env-A 2300 Rule, PSNH has consulted the software vendor which supplies the DAHS and is reviewing the best available option to manage this averaging period. Current method ofachieving this is through a new "Smart Reporting" software trial program

. PSNHis confident in working with the vendor that the rolling average period will be achievable. Preliminary information suggests that implementing the new software has an estimated cost of$10,000and an annual recurring cost of $2,017(1 . 2 - Mwatensinm

Impacts Calendar Month Analysis Previously Submitted),' pSNH's highest priority is ensuring compliance with all emission limits. PSNH has reviewed historical data and concluded that start-ups, shut downs partial load operating conditions and upsets can significantly impact average emission rates. PSNI-1's current method of operation to account for these events is to operate NOx control equipment to maintain an emission rate of

### Mr . Robert Scott, Director

December 15,2010 Page 4 of 7 approximately t) .25 lb1MMBtu calendar month average to ensure compliance with the 15.4 ton/day limit or the equivalent 0.371b/MMBtu emission rate. This method of operation results in approximately a 0. t S lWMBtu difference between the average NOx emission rate and the limit, this allows for operational flexibility as described above (i .e. start-up, shutdown, partial load operation etc) . Further limitations based on a calendar month would impact operation and increase incremental maintenance and capital cost. For complete breakdown of the costs represented in Table 2a. and a calendar month analysis reference PSNH's August 16, 2010, submittal . Table 2a. Incremental Maintenance and Capital Cost

Errmissitan Calendar Annual Increase Predicted Limit Month Loss of Maintenance Incremental (IblNXmBtu) control Investment (Cost ofAir Cost



### Target ofSCR heater and {lbJMMBtu) Catalyst SCR

. Maintenance) 0.37 U

.22 so $O S{? ' 0 .34 0

.19 $143,000 $195,004 ~33$ OOQ 

### 3t}-Da~r Rolling Averas~e analysis: In addition to the above analysis and based on EPA comments to the draft rule and DES's request for additional information, PShtHfurther analyzed the impact of changing its current method which is based on a calendar month average and reviewed a 30-day rolling emission limit, as well as the incremental cost associated with this limit. PSNH agrees with EPA that the 30-day rolling average method addresses flexibility for start-up, shutdown, emergency and malfunction. However, additional flexibility is necessary to maintain short termpartial load capability. PSNH has determined that a 0.30 lblMMBtu emission rate on a 30-day rolling average will accommodate reasonably anticipated operating scenarios while achieving approximately 24°fo reduction in potential emissions. The maintenance costs that will be incurred by complying with this limit is estimated to be $3{1,004 per year, and can be attributed to additional cleaning and inspection of the SCR and air heater. PSNHalso analyzed more stringent limits and determined costs similar tothose represented in Table 2a above would be incurred, The increase cost associated with a more stringent limit can be attributed to the cascading effect of increased loading of the SCR

. Increased loading of the SCRresults in the following conditions each more irnpactful as loading increases. More detail associated with these conditions can be found in the August 16, 2010, PSriHsubmittal . 

### 1) Blinding ofCatalyst;

2) More Frequent Maintenance Outages; 3) Fouled reagent distribution nozzles; 4) Accelerated catalyst derogation; and S) Loss ofinvestment of catalyst.

### Mr. Robert Scott, Director

December 15, 2010 

### Page 5 of 7 Table 2b Incremental MaintenanceandCaDital C based on Rolli ng Average Emission Annual Increase Limit Loss of Maintenance (1blt+lIMBtu) I Investment (Cost ofAir 0.37 4.3{I 

### o.2s-o.3o As noted in condition 2 above therewill likely be additional maintenanceoutages to ensure optimumSCR performance. Replacement powercosts that customers would incur froman additional maintenanceoutage are described in Item 3 . 3 - Replacement Power Costs associated with more stringent limit than Q .301hrI4iNIBtu NOx Em ission Rate Merrima,ck Station will need to consider a number of additional compliance efforts ifnot provided the necessary flexibility to deal with events as described above. Increased maintenance costs to maintain peak NQx reduction capability could be signifc,ant. For example, air heater and SCRcleanings wilJ be required more frequently because of increased loading ofthe SCR

. This results in additional maintenance costs and replacement power costs associated with the required outages. In addition to the maintenanceoutages additional cleaning will be completed as a proactive measure during forced outages resulting in delayed start-ups . Outage duration is fromtime offline until the unit is phased. Of SCR heater and Catalyst SCR

Maintenance) Predicted

Incremental Cost $U s(} so $o $30,000 1 x30,000 1 990 _$195,000 $338,000

If air heater washing were completed to comply with a step change in the NUx rate as shown below, the cost per ton of NQx reduction would be extremely costly. Again this number can increase greatly if an air heater cleaning was completed during a high priced market . Table mpact of more stri ngent Lim it F Replacem~nt Power Cost ~e Per putaae Short (3 days) __ IM A ,pvkp Mid_(4 .5 days) ~

.y . $1 ,100

, 000 Long (6day

s) __$1,4A(#,040 Replacement Power Costs : Thetable uses an assumption of $3tllmwhr difference between the cost of MK2and the market cost . This number can vary greatly depending on energy market prices. It should be reiterated to meet more stringent emission rate than t} .30 1b NQxIMM'.Btu, under the conditions referenced above, PSNH may be forced to shutdown for air heater/SCRcleaning and also may be forced to shutdown rather than operate at partial load. Each ofthese aforementioned scenarios has significant cost as described above in Table S.v ~ o °

4M g oo

° ° ° ~ ~ ~ .. ~ wr~ w~



### a °' ° w°~ 6°n °o °~ ~ 0~, a

.~ a 10

~ "r s~r rr~ _a F rn . . . cti ~' o °c C ; C ;

: ~ 64

~ © , .~ ~ . -r ^_ " M M ~ V! v c v 0

F

M

### Mr. Robert Scott, Director

December 15, 2010 

## Page 7of7 PSNHunderstand the cost per ton ofcomplying with the {1 .34 thfMMBtu calculated on a 34-day rolling average is under the BART threshold and is willing to accept this limit, which results in approximately 20%reduction of MI+C2's potential Nt?ar emissions. This analysis demonstrates that the implementation ofa more stringent limit than t?.301611vINIBtu will result in significant cost to our customers -with little cnvironmwrntal benefit . With running the SCR hander, more frequent air heater cleaning, extended outages, and forced outages, and limit partial load operation. 

### Ifyou have questions or require additional information, pleasecontact me at 634-2440or Sheila Bttrkc at 6342512

. Sincerely, Elizabeth H

. Tiltotson 

### Technical Business Manager--Generation cc: Sheila Burke, Generation Staff David Cribbie, Generation Staff