# --·**-~** STATE OF CONNECTIC U T DEPARTl\1ENT OF ENVIRO N l\1ENTAL PROTECTION

STA

### IE OF COl\TNECTICUT VS

. 

### ORDER NO
. 1 4 94 

### MOD IFI CAT ION NO.2 T HE C Ol\TNEC Tl CUT LI GHT AND POWER COMPANY CONSENT ORDER l n the matter of a co nsent o rder between the Commissioner of Em·ironmental Protection ("Commissioner' ' ) and The Coru1ecticut Light and Power Company ("Respo ndent "). WHEREAS. the Commiss io n er and Respondent. havi ng ag r eed t o 

### th e terms and co nditions s et forth in Consent Order No
. J 494 

### iss ued 

### on October I 5, 1996, 

### and the Consent Order No. 1494 

### Modification issued on 

### May 14, 1997. 

### do now. by mutual agreement. mo dify sai d Consent Order as follows: J
. 

### Exhi bit 2 

### to Co n sent Order No. i 494 

### is deleted in its entirety and the attached docl.Jr p em titled ''C redit Tradingfor Sources wi1h Irregula r NOx Emissions", 

### revised November 5. 1997. 

### is substituted in li eu thereof. 2. 

### Parasraph B.l.c. i s de leted and the followi ng is subs tit uted as a new paragraph B. J. c:

R

e sp on dent's Initials: ln accordance with the Departmem o f Envi ronmental Protecti on's Cr edit . Tradingfor Sou rces w ith Irregular NOx Emissio n s 

### po l icy, d ated July 

### 18,
. 1 995 , 

### prior to th e beg innin g of the 19 9 7 

### ozone s e aso n , fo r use during the 1997 

### ozone season, Respondent shall have in its possession 783 tons of ERCs. l f 

### such ERCs are not in Respondent's p o ss ess ion prior to u se, the number of ERCs re. qu i red shall doub le. Duri ng the 1 997 

### ozo ne seaso n , the Cos Cob and So uth Meadow Internal Combu stio n Units (JCUs) will be restricted in use t o no more than 16 

### hours of operation per day, and the Branford , Devon, Frankli.r. Drive, Middletown, Montville, Torri ngto n Terminal , Tunnel and Norwalk ICUs will b e re stri cted in use to no more than 1 

### 2 h ours per day. l n accordance with Exhibit 2, prior to the beginning of the 

### 1998 ozone season, for use during the 1998 

### ozone s e ason , Re spo ndent shall hav e in its possession the greater of: 1) 

### the to tal anticip ated ex cess N Ox em issio n s in 

# C. D ate : 

# f/!{)/7tf I (Print e d on Recycled Paper ) 79 E lm St r eet • Hu tf ord, CT 06 1 0 6 · 5 127 hu p ://d cp . s tate. c l. U£ A n Equa l Oppo r1un iry E m ploye r

### THE COJ\TNECTlCUT LJGHT AND PO\VER 

### COMPANY 2 

### CONSENT ORDER NO. 1494 MODIFICATION tons for the entire ozone season (mass basis); or 2) the maximum estimated excess NOx in pow1ds per day divided by 3 divi
. ded by 13 pounds per day per ton (peak (daily rate) basis). The**W1de~ ying**  

### emission rates, units, and hours of operation set forth in Exhibit I may be modified only after the consent of the Commissioner by wrinen modification of this Order. 3. Paragraph B.2.a. is added as follows: On January 7, 1998. February I 

### 0, 1998 , and March 6, 1998, Respondent submitted documents to the Commissioner, for his review and approval, representing the creation of 234 tons ofER Cs. excluding th e ERCs su it able for conversion to allowances for use under the proposed
. lOx Budget Program, from its Norv-.'alk Harbor, Montville, and Middletown Stations during the 1997 ozone season(" I997 ERCs"). Ten (1 0) 

### percent of th e 1997 ERCs have been retired and permanent ly rem o v ed to assure a benefit to the environment. If the Commissioner does not accept for use any, or a portion of the 234 tons of 1997 ERCs, Respondent shall provide and retire the balance ofERCs needed within fifteen (15) days ofwrinen notification from the Commissioner, such that the total of 1997 ERCs plus approved ozone season ERCs is equivalent to the ERCs required for the 1998 OZ0 }1e season as calculated in paragraph 2 above. If ERCs are not in Respondent's possession prior to use, the number ofERCs required shall double. All other terms and conditions of Consent Order no. 1494 issued by the Commissioner acting under Chapter 446c. Sections 22a-6, 22a-1 71, 22a

- J74, 22a-176, 22a

- 177 and 22a-178 of the Connecticut General Statutes shall remain in effect.

Respondent's Initials: Date:/ 

### THE CONNECTICUT LIGHT AND 

### PO\VER COMPAN'l'' '"' ,) 

### CONSENT ORDER NO. 1494 MODIFICATION

-·· 

### The COimecticut Ligh t and Power Company hereby consents to the entry of**thi~..modification** 

### to tbe 

### Consent Order without further notice.

TypeName: R. G. 

### Chev alier Type Title: Vice Pres ident

Entered as a modification**~.fr:!n** 

### Order of the 

### Com numbered 1494 

### thi s (; day of _:....__:=l-.::r---1


### Anhur J. 

### Rocque, Comm i ssioner TO\VNS/CITIES OF Branford, Greenwich. Torrington, Milford , Middleto · wn, Montville. Hartford, Preston. No rwal k LAND RECORDS MAILED CERTIFIED 

### MAIL

RETURN RECEIPT REQUESTED Certified Documem No. 0 6 2 6 54 4 9 

### 6NO
. 2



### REVISED 111519 7 

### Credit Trading for Sources with Irregular NOx Emissions The following outlines the Department's concerns and methodology for dealing with NOx compliance pursuant to §22a-17 4-2 2(j), Regulations of Connecticut State Agencies ("Regulations"), emission trading for "peakers" and other somces that ha.ve peak emissions that are substantially higher tl1an their average daily emissions. For pw-poses of this protocol, peaking units are defined as sources ·with peak daily NOx emissions greater than three times their average dail y emiss ions during the ozone season. The basic concept of the trading program is that somces with excess NOx emissions (a rate that exceeds the rate limits in the Regulations) may obtain NOx emission reduction credits ("ERCs") from sources that have " over-comrolled" their NOx emissions. Although typical somces can obtain credits on a mass basis (one ton ofERCs to offset one ton of excess emissions) with an acceptable environmental omcome , sources with large variations in emissions from day to day pose an additional problem for ozone attainment planning. The most co mmon peaking uni ts or "peakers" are electricity generating units that run during times ofhigh electricity consumption. Electricity demand is often the highest during hot , humid days of the swnmer when the potential for ozone formation is also high
. Peakers frequently have high emission**rates ~**  

### To the extent that these units produce emissions at exactly the time when emissions need to be reduced to limit ozone formation, allowing peakers to continue to comply with new rate limits through the use of ERCs on a ton-for-ton basis will exacerbate this effect. On the other hand, 

### if it can be demonstrated that the ERCs being used by peakers were generated on a comparable basis (i.e., during days of high ozone potential), then ton-for-ton use by peakers would be appropriate. The full impact of the NOx emission s from these t y pes o f faciljries during summer operati on must consider temporal variability as well as mass o f excess emissions. Any ERC trade must consider equivalency to the NOx reductions that control equipment would produce on an ozone day on both a temporal and a mass basis. The protocol below places appropriate requirements on peaking units to reflect the greater impact ofNOx emitted under this type of usage pattern. Attaclunent 1 provides a detailed example ofthis issue. 

### NOx Emissions Reduction Credit Use Co mputation For Peak.ers

• Peaking units are on ly considered to be a temporal issue for the ozone season months. • All excess NOx emissions during the winter (non-ozone season) need only be offset by ERCs on a mass basis. • Prior to each ozone season there will be a prospective calculatio n to determine how many tons of ERCs must be "on hand" during the ozone season. A retrospective calculation will determine how many ERCs were actually "used" during the ozone season.

(Printed on Recycled Ptpcr ) 79 Elm Street • Htrtford, CT 06106 · 5127 

### ('i'\ f'lu.o)._ Opportunity Employer 1494.'**~ONNECTlCUT** LIGHT .; POWER COHPANY



### For ERC use during rhe 

### o:;one season: EXHIBIT 2 2 MODIFICAT ION NO
. 

### 2

1. Prospective calculation determines the number of ERCs that must be provided for the ozone season. (Beginning 

### in 1996 , the ERCs must be in place no later than June 1.)

,· ERCs required for the ozone season shall be calculated based on : . (a) a mas s basis (total anticipated excess NOx emissions over the ozone season) and 

### (b) a peak-day basis (maximum excess emissions for any day during the ozone season). Sources ·will be required to provide credits equal to the g r eater of the amount calculated on a mass or p eak-day basis. The timing of actual credit provision ·will be governed by the terms of the specific trading order issued for that source. (a) Mass basis : ERCs required will be equal to the total number of t ons of an t ic ipated excess NOx emissions over the entire ozone season, calculated in the same manner used for other sources using ERCs (i.e., including any discounts)
. (b) Peak (da ily rate) basis: ERCs (in tons) required v-.rill be calculated by dividing one-third of the rnaxirrnun dai ly excess emissions* (in pounds) by 13 pounds/day/ton: ERCs required. (tons)= [(Maximum Estimated Excess NOx 

### in lbs.) + 3] + [13 lbs ./day/ton] *Where maximum daily excess NOx emissions are the difference between the m.aximum estimated hours of operation per day at the full- l oad-emission-rate and 95% oftbe allowable NOx emissions under Section 22a-174-22(e) ofthe Regulations. 2. Retrospective calcul ation ·will determine the actual credit use and the ERC surplus, if any. At the end ofthe ozone season, th e calculations required in item 1 above v-1).11 be repeated

. using (a) the actual total excess emissions for the ozone season, and 

### (b) the maximum

actual excess NOx emiss i ons on any of the days projected by the Corrunissioner to be "moderate t o unhealthful", "unhealthful", or "very unhealthful". The actual "ERCs required" will be the g r eater of the ERCs calculated on the basis of t otal mass or maximum (peak) 

### day. To the extent that the number of ERCs u sed to offset peak day emissions exceed the total mass of excess NOx emissions for the ozone season, the remaining mass value of such ERCs may be carried forward for use i n the winter (no n ozone season). 

### Any unused ERCs may be carr i ed forward until May 1, 1999, except as may be limited by the tradin g agreement and order, or by regulation
. Respondent ' s Initials '

# ~ Date :"---- er· nrtec - ·r 11 >M ·o t td'**ONNECTICUT** 

### LIGHT .t ' 

### POV.TER COMPANY 8**«lr?C r:m--.w~**  ncr= 

### EXHIBIT 2

A ttaclz m e nt 1 ERC Calculationfor Peaking Units 

### CONSE NT ORDER NO. 1494 MODIFICATION NO. 2

· ' Unless it can be demonstrated otherv.rise, ERCs are assumed to be created by relatively small daily reductions in NOx emissions over the course of an entire ozone season (153 days). The average daily NOx emissions reduction represented by one ton of credit i
. s 13 poW1ds/day calculated as follows: (1 ton) x 

### (2000 pounds/ton) -:- 1 53 days= 13 pounds/day/ton Thus, an ERC (ton) would be equivalent to a reduction in NOx emissions of 13 pounds/day. EXAMPLE. If a "peaking" source were to emit one ton of excess NOx per day when operating, but only operates for five days during the ozone season, the ov.'Iler / operator of the source would nominally need to obtain five tons ofERCs. However, those ERCs are likely to have been created by relatively small daily reductions in NOx emissions over the course of an entire ozone season (153 days). In this example, assuming a purchase offive tons ofERCs, that calculates out to a dailv NOx reduction of approx imate ly 65 pounds. (5 tons x 

### 2000 pounds/ton)-:- 1 53 days= 65 pol,lD.ds/day Clearly, on any day ·that the "peaking" unit operates, there is much more excess NOx emissions that will not have been offset , on the order of 1,935 pounds: (1 ton x 

### 2000·pounds/ton)- ( 65 pounds credit) = 1,935 pounds excess NOx emissions While the total amount ofNOx emitted would be contro ll ed on a seasonal avera ge basis, on the "peaking" day there would be a potentially significant increase 

### in NOx emitted, and thus an increase 

### in potential ozone creati on. In order to achieve a commensurate redu c tion in ozone creation potential for peakers, an adjustment in the calculation ofrequired ERCs is needed. One approach would be to require ERCs 

### in a quantity that would ensure that the daily average reduction represented by those ERCs would equal the maximum daily excess NOx emissions from the peakin g source on any day that it ran. On this basis, a peaking source with a maximum 24-hour excess NOx emiss i on of one ton would be required to purchase 153 tons ofERCs. 1 (ton)/d.ay X 1 53 days/season= 153 tons This 153 tons ofERCs would be adequate to "offset" excess emi ssions of one ton per day for as many days as the source operated during a particular ozone season. This has been deemed to be unduly stringent, given some diversity in operation of these sources. In light of the foregoing, this requirement is adjusted do'V.'Ilward by two-thirds
. NovemberS, 1997 " 0:\PITBLADO\R.EPORTIPEAK.ERS Respondent's Initials'

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