ML20235F111
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. DISCUSSION AND CONCLUSIONS OF ENVIRONMENTAL IXPACI BY THE
- d. S. ATOMIC ENERGY C0K41SSION
. DIRECTORATE OF LICENSING CONCERNING THE PROPOSED ISSUANCE OF LICENSES TO THE
_ COMMONWEALTH EDIEON COMPAh7 A'*D THE .
IOWA-ILLINOIS CAS AND ELECTRIC COMPANY s
FOR EMERGENCY OPERATION OF QUAD-CITIES NUCLEAR POWER STATION UNITS 1 AhT 2 DOCKET NOS. 50-254, 50-265 Issued May 4, 1972 e
B709290418 B70921' .
PDp
Table of Contents Page No. !
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Introduction .............. ................................
2 Conclusions ................................................
5 l Statement of Environmenda1' Considerations ..................
5 l A. Biological Effects ..............*.................. ,
Heat removal system effects ................... 5 L 1. ;
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- 2. Chlorination effects ..........................
1 B. Radiological Effects .............................. 10 I
- 1. Normal Operation .............................. 10
- 2. Accidents ..................................... 10 Additional Construction Effects ................... 10 C. .
1 10 D. Other Effects .....................................
Redress of Impacts ................................ 11 E.
F. Foreclosure of Alternatives ....................... 11 G. Verification of Environmental Impacts ............. 11 11 Facility Operating Considerations...........................
Effect of Delay ............................................ 12 i
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-INTRODUCTION On April 12, 1972 the. Commonwealth Edison Company and the Iowa-Illinois Cas and Electric Company (Applicants), in. a letter. from Mr. .Bryon' Lee, Jr.
to Br.1 Peter A. Morris , requested,; pursuant to Paragraph ~ D(3) of Appendix'
' D of 10f Code of Federal Regulations Part 50, authority to, complete all-L
. but to do so
'necessary testing' of each unit up to. its full power rat ng.i witt out at.any time operating the two units at an aggregate power level. in ~
excess of one-half of their~ combined-capacity. The Applicants also requested , 1 authorization to operate the station af ter testing is . completed until ..
September 15,1972 (the anticipated end of the summer peak electrical load period) in the following manner
- a. Upon completion of the power test program, to operate at power levels up to'200 MWe for each unit. This. minimum level is required to avoid damage to the turbine from operation for extended periods at levels below 200 MWe;
- b. To operate above 200 MWe, but not more than 500LMWe for each unit, only on those days in which, in the judgment of the system load ,
dispatchers, total demand is likely to exceed available capacity unless. ,
the Quad-Cities Station capacity is greater than 400 MWe even if all available . emergency power were purchased. Such operation can be expected; on days when the air temperature exceeds 90*F or unusual outages are l
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- c. To operate at power. levels above 500 MWe only when in the judgment of the system load dispatchers, capacity in excess of that. amount will be required to meet demands. Operation above 500 MWe is not. expected to occur for more than eight hours in any 24-hour period.
The application of The Commonwealth Edison Company and The Iowa-Illino'is Gas and Electric Company (Applicants) for licenses to operate the Quad-
- Cities Nuclear Power Station Units 1 and 2 (Station) is presently under ,
l consideration by the Atomic Energy, Commission (Commission) regulatory staff (AEC staff). Appendix D of 10 CFR Part 50 to the Commission's ]
Regulations, which implements the National Environmental Policy Act of
,.1969 (NEPA), establishes procedures for an environmental review of such
- facilities. On March 6, 1972, the Draft Detailed Statement on the Environ- j mental Considerations required by Appendix D was issued and circulated for .j comment. .l J
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Appendix D provides a procedure in.Section D.3'for issuance of an interim operating license authorizing the loading' of fuel in the reactor core and limited operation of the facility. This procedure.may be ' applied to
' applications = for an operating license for a: nuclear facility. for_ which the commission published a . notice of opportunity for, hearing prior to-r October 31,.1971,fand no hearing was requested., The limi ted license may be issued by the Commission, pending theicompletion of an ongoing NEPA environmental review'of a full-power license application upon a showing that such ' licensing action will not have a significant adverse impact on f
the quality of the environment, or af ter. considering and balancing the
- factors described in'Section D.2 of Appendix D, and upon the Commission's making appropriate findings on the matters specified.in 10 CFR Part 50.57(a); , !
provided, however, that operation beyond 20 percent (20%) of . full power will not be authorized . except in emergency situations or other situations where ~ the public interest so requires.- Any license so issued will be without prejudice to subsequent licensing action'which may be taken by
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the Commission with regard to the environmental aspects of the facility, >
and any license. issued will be conditioned to that effect. ,
This Discussion and conclusions. is based primarily on the Draf t Detailed Statement on the Environmental Considerations issued on March 6.1972.
It'is noted that on March 27, 1972 the Applicants have entered into an agreement with the plaintif fs to the litigation in the U. S. District Court.
for the District of Columbia, The Isaac Walton Learue of America et al.
vs. James Schlesinter et al.; People of the State of Illinois _ et al vs.
2207-71 and
,U. S. Atomic Enerev Commission et al.; Civil Action Nos.
2208-71. On April 4,1972 the Iowa Conservation Commission granted a permit to construct the dif fuser-pipe. .
I-On April 25, 1972 the Illinois Pollution Control Board issued an opinion
. and supplemental order that permitted a variatica from the state water quality standards on an emergency basis until the diffuser is installed and : operating but no .later than August 15, 1972. It is further noted that on March 31,1972, 7acility Operating License No. DPR-29 was amended and No. DPR-30 was issued to Units 1 and 2 respectively to permit operation of each unit at power levels up to.502 MWe, 20 percent of rated power.
- These licenses are in effect until June 1,1972.
CONCLUSIONS
- The Regulatory S.taff is required to review the proposed operation of
- Units 1 and 2 as indicated above in the framework of the following factors specified in 10 C7R Part 50, Appendix D Section D.2:
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- These conclusions are pursuant to 10 CFR Part 50, Appendix D. Findings required by the provisions of 10 C7R Part 50.57(a) have been set forth
in the Safety Evaluation dated August 25, 1971.
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"(a) Whether it 4s likely that. limited operation during the pro-spective revicu period will give rise to 'a significant, adverse; impact on the environment;.the' nature and extent of.such impact, if- .1
- any;.and whether redress oflany such adverse environmental impact can reasonably be effected should modification or termination of:the M limited license result from, the.' ongoing NEPA review.
"(b) Whether limited operation.during the prospective review period.
would foreclose subsequent adoption'of alternatives.in facility design or operation of the type that could result from the ongoing NEPA ~
environmental review.
"(c) ' The ef fect of delay in f acility operation upon the public interest ;
.0f primary importance under this' criterion are the power needs to be served. by . the facility; the availability of alternative sources, if any, to meet those' needs on a timely basis; and delay costs to the licensee and t'o consumers."
The Reg'ulatory Staff has reviewed the Applicants' request and, based on
,eval ua tions' set forth in-the March 6, 1972,--Draft Detailed Statement of the Environmental Considerations and herein, has reached the following conclusions: ,
- s. Operation .of both units at power levels up to 25 percent of .
rated power each, during the period ending April 1,1973, will likely give rise to only a minimal impact on the environment. As' discussed below, this. potential impact is due to chemicals, particularly chlorine and chlorine derivatives.: and heat added to the condenser cooling water.
This impact would be localized and is not likely to have a' measurable
'effect on the:overall aquatic population:of Pool 14.* Furthermore, should
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this proposed operation be terminated, recovery of the aquatic biota in Pool 14 would be good and probably complete.
Operation of both units at power levels from 25 to 100 percent of full power.on an intermittent basis will result in an adverse impact-
- on the aquatic environment.. This impact will be localized to the island
-area below the-station, the slough area downstream and across the channel
'*The section of .che Mississippi River between Lock and Dan 13 and Lock and Dam 14 on which the Station is located.
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from the Station', and the east bank' of. the river; possibly 'as faf as .
- Cordova. : This impact 'is due to the heated water and possibly Lthe chlorine' and chlorine derivatives., This impact :is not .likely to affect the upper half l of Pool 14. ~ Should this operation be . terminated by changing from the side-jet ' discharge to the diffuser-pipe discharge, the recovery .of-
- the_ aquatic' environment in thel affected; areas would be good but take longer
- than the. recovery from steady state 25 percent operation.
j b., Operation of :the station under the lir.ited license would not
' foreclose subsequent adoption. of alternatives in the -f acility design or.
- ' in the operation of the Station of the type. that' could- be required as a
- result'of the ongoing supplemental NEPA environmental l review.-
- c. There will be an adverse effect upon the public; interest as a result of. delay.in facility operation. The Federal Power Commission (FPC),
in its December 20,-1971 letter, has stated that it is' essential that these units be 'available for power generation by this summer. This has been
' reaf firnied in the March 22, 1972 FPC comments on the Draft Detailed State-ment on the Environmental Con:.iderations. The FPC letter and supporting data confirm the Applicants! statements to the effect that an emergency situation exists with regard to the public need for power.
After considering and balancing of the foregoing factors and making
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appropriate findings on the matters specified in 10 CFR Part 50.57(a),
we therefore conclude that granting of the application for the interim operation of the Station would be consistent'vith the emergency require-ments of Section D.3 of Appendix D of 10 CFR Part 50. .
The foregoing operation is. contingent up'on the Applicants' establishing -
-and maintaining a monitoring program as delineated in the. Technical Speci-fications. Furthermore, the Technical Specifications require a report on the operations to be submitted af ter the limited operation is concluded identifying observed environmental effects and means to assist recovery of the environmental damage.
Any license for limited operation of the Station will be without prej-
'udice 'to subsequent licensing action which may be taken by the Commission.
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) . jj STATEMENT OF ENVIRONMENTAL CONSIDERATIONS.
. 'A. Biolottical Effects ,,
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- 1. . Heat Removal System Effects
' ' a'. Condenser Cooling Water Intake:
p, legardless .of the power level 'of' operation or mode of once-through cooling discharge- (side-jet "or diffuser-pipe),J the ecological = considerations of-
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1 the water. intake system discussed in the Biaft Environmental Statement
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(V.C.2.a-1, p. 75)' are applicable to this propesed license, . assuming that all six intake pumps operatW at fdll, capacity (2270 cfs). Any reduced level of pumping would tend to. riduce. the impact 'of the water, intake :
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system. The staff concludes that the' mechanical' screening devices - (float-ing barrier, trash' racks, and, traveling screens) will not prevent motile' aquatic organisms from entering the intake canal and establishing
'" residence" in the canal, or protect some of the less-motile species D from potential destruction due to impingement on travelling screens or condenser entrainment. These problems will occur to some extent which
'is not readily quantifiable, and determination of the ' degree of occur-l rence and the need 'for remedial action' will be. required by the Commission-as' part of the Applicant's environmental surveillance program. .
- b. Condenser Passage:
In passing through the condensers and ~ the discharge system (side-jet or diffuser), entrained organisms will be' subjected to mechanical, thermal
- '(up to 23'F temperature increase) and chlorine damage (intermittent).
These. effects are not readily separable from each other under routine operation.
4 When intake temperatures are relatively high (June, July, Aug. , Sept.), ~
J maximum thermal damage to entrained organisms is expected and the potential I exists for > 20 percent mortality of river plankton (based on low river flows and maximum intake flow).- Ec,vever, studies conducted by Bio-Test Labs at the Riverside Generating Station (Pool 15)I showed that during May, June-and July 1971, a AT of up to 8'c (15'F) resulted in less than 10 percent r
2 Beer, L.P. , and Pipes , W.O. , A Practical Approach to the Preservation of the Aquatic Environment: the Effects of Discharge of Condenser Water into the Mississippi River, Commonwealth Edison Company, Chicago, Illinois 1968, 210 pp.
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- ' . mortality of entrained zooplankton. Other studies discussed in the Draft d Environmental Statement indicate that although significant plankton i mortality may occur at higher AT's (100 percent for fish larvae and >20 -
percent for zooplankton), no quantifiable adverse effects were observed on the aquatic system. ' 4 Based on the above considerations and the discussion in the Draft Environ-mental Statement (V.C.2.a-2, p. 76), the staff concludes that even if 100 percent of the condenser entrained plankton are lost (maximum of 20 percent of river plankton during low flow periods), a reduction in the
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number. of species or individuals immediately downstream may occur, but the overall community structure of Pool 14 will not be adversly affected.
However, the Applicant will be required to determine the effects (immediate and long-term) of conden'ser entrainment on river biota and the community structure of Pool 14.
- c. Condenser Cooling Water Discharge (1) Side-Jet:
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.lThe side-jet discharge will most likely attract a variety of fish species during various seasons, creating the potential for both thermal and chlorine -
effects on fish. Although many studies have shown that acclimation tem-perature determines upper and lower lethal temperatures, field studies have not absolutely determined temperature changes to be the cause of fish kills. A study shows 2 that many warm water species of fish (largemouth bass and sunfishes) can tolerate rapid temperature increases and decreases of up to 20*F; morta11 ties which resulted from temperature changes of this magnitude varied with species and generally were restricted to diseased or otherwise stressed individuals.
In sunemry, the degree of fish congregation in the discharge canal and
- in the immediate plume area cannot be predic'ted at this time. It is ex-pected that at any level of Station operation there will be some attraction of fish to these areas, and that the species composition and size of this
" resident" population will change on a seasonal basis. When fish are in 7Nickum,,J. ~
G., "Some Effects of Sudden Temperature Changes Upon Selected Species of Freshwater Fishes," 1966 Pd.D. Thesis, Southern Ill. Univ.
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the canal and immediate discharge area, they are subject to the potential damage caused by temperature changes and chlorination. According to the above discussion, such fish are not likely to be adversely af fected except possibly in the case of a rapid shutdown during periods of 100 percent '
Station power output (6T 23*F). This leads to the need to avoid unplanned shutdown whenever practical. If shutdowns are planned, rapid shutdown should be avoided.
l The heated discharge from the side-jet may affect the benthic communities near the outfall to the river, as discussed in the Draf t Environmental Statement (V.C.2. a-3, p. 78) . However, based on the available field data, it is not likely that any major changes will occur in the benthic
. communities of Pool 14.
The staff concludes that in the immediate discharge area (i.e., the mixing l zone), there may be a seasonal change in organism diversity, abundance and productivity different than that prior to Plant operation. The mag-nitude of these changes will be greatest at full Station power and pro-portionately less at 50 and 25 percent operation. Less temperature tolerant motile species will evacuate the area and may be renlaced by species that prefer the warmer discharge water. The less temperature tolerant benthic species will not survive in this area and may be replaced by more temperature tolerant species. The Applicant will be required to monitor the nature and magnitude of effects on benthic communities in and near the of = h4rges.
Downstream areas that vill experience temperature rises consist primarily
- d4 ch r~ .1, channel border, littoral regions along the banks and a EAali k:ea of island (Illinois shore), as discussed in the Draft Environ-mental Statement (V.C.2.a-2, p. 81). Although the island area has been shown to be frequented by many of the sport and commercial species of I interest in Pool 14,3 it appears that upstream island areas are utilized to a greater extent by these species. It is certain that the small down-stream island area is utilized for spawning during the spring by some of these species (such as sunfishes, bass, and catfish). However, it is doubtful that significant spawning occurs during other seasons (June-Feb.).
Modeling studies predicting the thermal plume behavior indicate that these
- islands will be contacted by warm discharge water during periods of river flow above 20,000 cfs (85-90 percent of the year). At full Station power, j temperature. increases ranging from 10 to 16*F (surface) and 4 to 12*F i
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Bio Test Labs, Fish Population Study, May-Dec.1971, Pool 14, Mississippi
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River (Project XIII). -
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(near-bottom) will be superimposed on the natural. temperature cycle in the island area. It is highly likely that the effects mentioned previously in the. discussion of the immediate discharge area vill also occur here.
Again, . the magnitude of this impact cannot be quantified. Less temperature l tolerant fish and motile invertebrates will retreat from the region and !
probably seek comparable habitats lower in the pool or above tha Station N resulting in a change in species diversity and abundance of organisas in
[ the' island ' area. At lower power levels (25 and 50 percent), the down-4
( ' stream thermal plume effects will be proportionally less, but some changes in diversity .and ' abundance of organisus may still occur in the island
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area. However, it is unlikely that a discharge of warm water that is ,
11.5'F or less above ambient (i.e. , for power levels 50 percent or'less) .
will adversely affect the overall ecological balance of Pool 14.
Downstream of the island area, the thermal pluce will be primarily a surf ace phenomenon (less than 6 f t depth) during the warmer months. At
. 50 percent Station power and river ' flow equal to 30,000 efs (a condition illustrated by the Applicants' monitoring studies), it is estimated that the three degree Fahrenheit isotherm will extend less 'than 10 miles down-stream; at 100 percent power, less than 17 miles downstream. No adverse biological effects are expected in the far downstream areas of Pool 14 l
'as a result of the thermal plume.
In summary, the biotic community of the downstream island area will be l altered as a result of Station operation. Changes in the number and kinds I of species, and the productivity of the area are expected to occur. The magnitude of these changes is expected to be a function of the Station power level. The Applicants will be required, as indicated in the Technical Specifications, to determine the nature an,d extent of changes induced by dae thermal plume, especially in the island area below the Station. Effort should be concentrated on changes in species diversity, of fish, benthos, and periphyton.
(2) Diffusgr-Fipe:
The discharge of condenser cooling water from the diffuser-pipe will result
, in nearly complete mixing within 600 feet downstream. The resulting temperature increase af ter complete mixing will never exceed 5*F and will be only 1 to 2*F above ambient most of the time. This is based on the modeling studies as discussed in the Draf t Environmental Statement (III.D.1.c-2, p. 44).
Organisms drifting downstream past the diffuser will be subjected to rather sudden increases in temperature (up to 23*F at full Station power) and turbulence. Fish attracted to the warmed diffuser discharge area O.
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will potentially be subjected to cold shock should the Station undergo a rapid shut down although this potential cold shock is not as likely to be as severe during the summer months as it would La during the winter months.
In addition, such fish may be exposed to water supersaturated with gases, resulting in the development of gas-bubble disease. The possibilities j of such damage will be taken into account by the Applicants' monitoring program as indicated in the Technical Specifications. ,
The staff coneludes that the diffuser-pipe condenser cooling water dis-charge has a smaller environmental impact on the aquatic biota because it !
disperses the heat more rapidly throughout the river and has a smaller
. high-temperature-zone than the side-jet. Since the high temperature zone is likely to be the zone of maximum biological effect, the diffuser minimizes the above effects more than any other once-through cooling system. However, the diffuser-pipe, or any once-through cooling system ,
af ter complete mixing, raises the temperature of the river. This temper- !
ature increase may tend to change the temperature character of the lower l half of Pool.14 to the downstream pools of corresponding temperatures. I The Applicants will be required. as indicated in the Technical Specifications, to determine the dimensions of the thermal plumes resulting from operation of the diffuser. In addition, the effects of discharged diffuser water on plankton and fish will be evaluated by the Applicants.
- 2. Chlorination Effects Sodium hypochlorite solution is added intermittently (40-minute periods, three times / day) to the condenser cooling water to reduce the growth of microorganisms in the system. Chlorine is known to be toxic to aquatic life. We have reviewed the literature as indicated in the Draf t Detailed Statement and observed measurements of. chlorine residual at the Station.
The foregoing indicate to us that well-controlled chlorination, involving the mixing of chlorinated streams with larger volumes of unchlorinated water in the discharge system, can lead to little or no chlorine discharge to the rivers and lakes.' However, there are no known published data which definitely establish this position. Because of the uncertainty involved and to assure that the environment is adequately protected, the Applicant will be required to monitor for residual chlorine and its effects on the aquatic biota so that remedial action may be taken if necessary. The Applicant will establish a test program to relate the total residual chlorine at the point of discharge to the sodium hypochlorite input and the monitored condenser concentration. The sodium hypochlorite input will be controlled such that the monitored condenser cooling water discharge level of free residual chlorine does not exceed 0.5 ppm for a cumulative period of time, j not to exceed two hours per day. . l
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No adverse effects are expected to result from the chlorination procedures
,to be utilized. However, the staff concludes that chlorine levels must be regulated as indicated in the Technical Specifications.
Ei. RADIOLOGICAL EFFECTS
- 1. Normal Operation As discussed in the Draft Detailed Statement (section V.D. , p. 87) 'the staff has concluded that the releases of radioactive materials during full power operation of the Station will. contribute only an extremely small increment to the dose that area residents receive from natural background radiation. Since . fluctuations in this background exceed this small incre-ment, the dose will be immeasurable itself and constitute no meaningful risk. The staff has further concluded that there will be no adverse effects on species other than man due to radiation exposure caused by operation of the Station. Operation under the proposed interim license would result in lower average power, the fuel would be newer and less subject to failure, the fissipn product inventory would be lower, and consequently there would be a lesser environmental impact than at steady ttate full power operation.
- 2. Accidents. 1 I
As discussed in the Draf t Detailed Statement (section VI. A. p. 98), the staf f has concluded that the environmental risks due to postulated radio-logical accidents are exceedingly small at fell power operation. Operation under the proposed license will be with new fuel at a lower average power .
and consequently a lesser potential environmental impact. ,
C. ADDITIONAL CONSTRUCTION EFFECTS ..
All construction needed for the requested testing and emergency op'eration has been completed as confirmed by onsite review by AEC inspectors. There-fore, there will be no further impact on the environment from construction I associated with this operation.
D. OTHER EFFECTS .
No new or spent fuel will be shipped for the requested operation, so there will be no environmental impact related to transportation, Similarly, no additional transmission lines are needed for this operation, so this will not lead to further environmental impact. The only other potential effect ident'fied is that related to transportation of solid wastes. The Draf t l Detailed Statement (Section V.E., p. 91 and VI.B. , p.104) discusses this
[ possibility for normal fuel power operation and finds that the risks to the general public would not result in a significant exposure to radiation.
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, au E. , REDRESS OF U{ PACTS As indicated in the Draft Environmental Statement (section V.C.2., p. 73) the environmental impacts f rom the proposed operation are expected to involve mainly aquatic life and to be recoverable. The nature of these impacts, though not readily quantifiable, are such that full redress can be expected. That is, fish may relocate or benthic organisms be replaced by other types, but resumption of normal temperatures will permit the reversal of these impacts. The staff has concluded that redress from the above effects can be expected.
F. FORECI.05URE OF ALTERNATIVES The Station is completed and already in the process of being tested up to 20 percent of. f ull power under licenses DPR-29 and 30. No additional changes are proposed in connection with the requested amendment of the license which would lead to foreclosure of subsequent adoption of alter-natives in facility design or operation of the types that could result from the ongoing NEPA review. The principal alternatives still practicable for the Station appear to be those associated with the condenser cooling water systes, and the ongoing development of the alternate cooling systems is not contingent upon the activities in the requested amendment. These alternatives are still being evaluated by the staff in the ongoing NEPA review.!
G. VERIFICATION OF ENVIRODIENTAL IMPACTS Any amended license issued to the Applicants will include requirements for I monitoring and evaluati'on programs to insure the necessary operating limitations to protect the environment are met. The Applicants will be i required to report the results of this program at the end of the period of l operation under this amended license.
, FACILITY OPERATING CONSIDERATIONS The application is being considered for limited emergency operation of Units 1 and 2 at a steady state level up to 25 percent of rated power (200 MWe, 620 MWt), up to 62 percent of rated power (500 MWe,1550 MWt) to meet load demands when other power sources are not available, and up to 90 percent of rated power (728 MWe, 2260 MWc) during emergency load demands provided that all other reasonable means to meet the
. emergency have been exhausted.
Operating below 25 pc.rcent of rated power has been demonstrated to result in unstable power generation system operation. Under this condition, the feedwater system is supplied insufficient steam flow from the turbine, to assure stable operation of the feedwater heaters.
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Thus, 25 percent of rated power is considered the lowest practicable steady state power level for each facility. At 62 percent of rated power, the power level can be increased by primary coolant flow control without moving the control rods from an established pattern. This mode of operatica provides a rapid means for incra.asing power to meet emer-gency load demands and minimizes the detrimental effects on the fuel that may result from the power redistribution induced by control rod
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motion.
The assesstent of environmental f cpacts on aquatic communities cannot be determined as precisely as would be desired due to uncertainties in the knowledge of the behavior of these aquatic communities. As a consequence, variations of 5 cr 10 percent in temperature change cannot be quantita-tively evaluated other than to indicate the direction of the effect.
Thus, the evaluation of operation of the Station at 25 percent of rated power, compared with the 20 percent of rated power assessed in the Draf t Detailed Statement on Environmental Considerations, is characterized as a slightly greater inpact. Similarly, the impact on the aquatic com-munity due to operation of th'e Station at 62 percent of rated power, as compared with the 50 percent in the Draf t Detailed Statement on Environmental Considerations, is somewhat greater.
EFFECT OF DELAY The Staf f discussion in the Draf t Detailed Statement (I.A., p.1) points out the need for power. On the basis of the review of the data submitted by the Applicants and the support of this data by the FPC, the staff has concluded that the effect of the delay of placing the Quad-Cities Station in service would lead to a serious power shortage in the area served by the Station in the summer of 1972. FPC comments on the Draft Environmental Statement (March 22, 1972) reaffirm the urgency of getting the Station j on line and indicate that the Commonwealth Edison Company has a reserve margin of only 5.4 percent without Quad-Cities units or the Zion unit. ]
The Commonwealth Edison Company's reserve margin had been projected to l
be 23.5 percent. The Iowa Gas and Electric Company would have a deficic without the Quad-Cities power. However, these effects are spread over a {
much larger area through the Applicants' participation in the MAIN power l i
planning group and the Iowa Power pool, thus the effects of delay are also spread over a larger area than that served by the Applicants. f The Applicants have further pointed out the schedule of operation (letter, l
Mr. Byron Lee, Jr. to Dr. Peter Morris dated April 12, 1972 Exhibit 1) which would permit the testing of the. reactors. This schedule indicates j that in order to be ready for the summer peak requirements the amended l licenses are needed as soon as possible, in order to be available during d
the summer peak demand for power. I t
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