ML19308D611

LER 78-024/04L-0:on 780911,during Spring,Summer & Fall Quarters of 1977,difference in Std Deviation Discovered in Aquatic Sys Metabolic Functions Preoperational Study.Caused by Variations in Sys

ML19308D611
Person / Time
Site:	Crystal River
Issue date:	09/19/1978
From:	FLORIDA POWER CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
LER-78-024-04L, LER-78-24-4L, NUDOCS 8003050777
Download: ML19308D611 (3)

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!.UPPLEMENTARY INFORMATION

1. Report No. : 50-302/78-024/04L-0 "x

2. Facility: Crystal River Unit #3

3. Report Date: September 19, 1978 ,

4. Occurrence Date: Spring, Summer, and Fall quarters of 1977 (discovered 11 September 1978) (determined at plant 19 September 1978)

5. Identification of Occurrence:

A difference of more than two standard deviations (>2c) existed between the preoperational study in the metabolic functions of the following aquatic systems adjacent to Crystal River Unit #3:

a) Inner Discharge Bay for Gross Productivity, Net Productivity, and Res-piration during the Fall quarter.

b) Discharge Salt Marshes (Soartina) for respiration during the Summer )

quarter and dead biomass during the Summer and Fall quarters. J

c) Discharge Salt Marshes (Juncus) for live biomass during the Spring, ,

Summer and Fall quarters. l 1

6. Conditions Prior to Occurrence: l l

I The site generation capacity factor for the first (Spring), second (Summer), and third (Fall) quarters of 1977 was 45%, 53%, and 67%,

. respectively.

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7. Description of Occurrence: l In Table 1 is the description of the preoperational mean, the preopera-tional two standard deviation (2r), the operational mean, and the determi-nation whether the operational mean was greater than (>) or less than (<)

the preoperational mean + two standard deviations for each of the items of Section 5 above.

8. Designation of Apparent Cause:

The apparent causes of the greater than two standard deviation change of i the metabolic functions in the Inner Discharge Bay and the Salt Marshes could be natural or seasonal variations or these variations in conjunction with the increased thermal output from the site due to Crystal River Unit i

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9. Analysis of Occurrence:

In the Inner Discharge 3ay and the Salt Marshes, the possible natural or seasonal variations in conjunction with the possible effect of the Crystal River Unit 13 addition to the site thermal discharge say have caused the change in the netabolic functions observed in the operational study as ecm-pared to the preoperational study. However, these changes say be temporary

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as the ecosystem reorganizes itself to the new conditions. The suggestion s_- of cause and effect by Crystal River Unit #3 can only be corroborated by the continuance of this study since greater than two standard deviation dif f erence did not exist between preoperational and the operational data in the remaining quarters.

8 0 0 3 0 5 0 ~/ ') ~/ f

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9. Analysis of Occurrence: (Continued)

A period of adjust:nent of the ecosystem was expected concurrent with Crystal River Unit #3's initial operation. nerefore, changes in the operation of the unit are not required, and the present program to monitor the environment will be continued.

10. Corrective Action:

ne change in tastabolic functions in the Inner Discharge 3asin and the Discharge Salt Marshes cannot, at this time, be attributed to either natural phenomenon or a specific man-made cause. Derefore, the present study will be continued to verify, if possible, the cause. Until such ti:ne, no corrective action can be defined.

11. Failure Data:

Ris is the second report for this type occurrence. Refer to:

78-022/04L-0, dated 31 July 1978.

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)RMa/idd v M02(9/05) l

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1E 1 Preoperational Opera t ional Operational Hean

> or < Preoperational Aquatic System Metabolic Function Quarter Hean 2 Hean Mean:L 2 g-

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Inner Discharge Bay Net Productivity Fall 1.20 0.32 0.27 <

(g 02 /m 2 -d)

Cross Productivity Fall 3.27 0.94 0.56 <

i (g 02/m -d)

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Respiration Fall 2.07 0.78 0.30 <

(g 02/*2-d)

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Discharge Salt Respiration Summer 2.03 0.70 1.25 <

Harshes (Spartina) (g C/m2 -d)

Dead Biomass Summer 447.1 149.0 282.4 <

(g/m2 ) .

Fall 462.7 258.8 180.4 <

'

Discharge Salt 1.tve Biomass Spring 500.0 218.8 1000.0 >

Harshes (Juncus) (g/m2 )

Summe r 531.3 312.5 1343.75 >

Fall 500.0 312.5 1484.4 >

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