HBL-08-008, Annual Radioactive Effluent Release Report for 2007

Annual Radioactive Effluent Release Report for 2007

ML081000562
Person / Time
Site:	Humboldt Bay
Issue date:	03/31/2008
From:	Sharp L Pacific Gas & Electric Co
To:	Document Control Desk, NRC/FSME
References
HBL-08-008, OL-DPR-07
Download: ML081000562 (22)

Text

Pacific Gas and Electric Company 1000 King Salmon Avenue Humboldt Bay PowerPlant Eureka, CA 95503 Loren D. Sharp 707/444-0700 Directorand PlantManager Humboldt Bay Nuclear March 31, 2008 9

PG&E Letter HBL-08-008 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Docket No. 50-133, OL-DPR-7 Humboldt Bay Power Plant Unit 3 Annual Radioactive Effluent Release Report for 2007

Dear Commissioners and Staff:

contains the Humboldt Bay Power Plant Unit 3 "Annual Radioactive Effluent Release Report," covering the period January 1 through December 31, 2007. This report is required by Section 5.7.3 of the Humboldt Bay Power Plant Unit 3 Technical Specifications. contains Revision 14 to the "SAFSTOR Offsite Dose Calculation Manual" as required by Part I, Section 4.2 of the "SAFSTOR Offsite, Dose Calculation Manual."

cc: Elmo E. Collins, Jr.

Joe Davis John B. Hickman PG FossilGen HBPP Humboldt Distribution Enclosures

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Enclosure 1 PG&E Letter HBL-08-008 HUMBOLDT BAY POWER PLANT UNIT 3 ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT January 1 through December 31, 2007

PACIFIC GAS AND ELECTRIC COMPANY HUMBOLDT BAY POWER PLANT DOCKET NO. 50-133, LICENSE NO. DPR-7 ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT JANUARY 1, 2007 THROUGH DECEMBER 31, 2007 TABLE OF CONTENTS INT R O D UC T IO N ................................................................................................. . . ... 2

1. SUPPLEM ENTAL INFORMATION ................................................................... 3 II. GASEOUS AND LIQUID EFFLUENTS ............................................................... 7 Table 1 - Gaseous Effluents - Summation of All Releases ................. 8 Table 2A - Gaseous Effluents - Elevated Release.- Nuclides Released ............. 9 Table 2B - Gaseous Effluents - Ground-Level Releases -,Nuclides Released ... 10 Table 3 - Liquid Effluents - Summationof All Releases .................................... 11 Table 4 - Liquid Effluents. - Nuclides Released ............................................... 12 II1. SO LID RADIOACTIVE W ASTE ........................................................................ 13 Table 5 - Solid W aste and Irradiated Fuel Shipments ...................................... 14 IV. RADIOLOGICAL IMPACT ON MAN ................................................................. 15 Table 6 - Radiation Dose for Maximally Exposed Individuals .......................... 17 V. CHANGES TO THE OFFSITE DOSE CALCULATION MANUAL (ODCM) ......... 19 VI. CHANGES TO THE PROCESS CONTROL PROGRAM (PCP) ...................... 20 VII. CHANGES TO RADIOACTIVE WASTE TREATMENT SYSTEMS .................. 20 VIII. INOPERABLE EFFLUENT MONITORING INSTRUMENTATION ................... 20 HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 INTRODUCTION This report summarizes gaseous and liquid radioactive effluent releases from Humboldt Bay Power Plant Unit 3 for the four quarters of 2007. The report includes calculated potential radiation doses from these radioactive effluents and a comparison with the numerical guidelines of 10 CFR 50, Appendix I, as well as a summary of shipments of solid radioactive waste. The concentrations of plant effluent releases during the reporting period were well below Offsite Dose Calculation Manual (ODCM) limits.

The information is reported as required by Section 5.7.3 of the Humboldt Bay Power Plant Unit 3 Technical Specifications and Section 4.2 of the ODCM, and it is presented in the general format of Regulatory Guide 1.21, Appendix B (except for the topics identified below).

Meteorology The meteorological data logging system was removed from service in 1967 so the information specified by Regulatory Guide 1.21, Appendix B, Section F, is not available. Previous Humboldt BayPower Plant Annual Radioactive Effluent Release Reports summarized the cumulative joint frequency distribution of wind speed, direction, and atmospheric stability for the period April 1962 through June 1967, when the meteorological data logging system was in service.

Short-lived Nuclides The Unit was last operated on July 2, 1976. Due to the long decay time since operation, short-lived radionuclides are neither expected nor reported. This includes lodines and noble gases other than Krypton-85.

Air Particulate Filter Composites - Sr-90 Air particulate sample filters are combined for approximately monthly intervals and analyzed off-site for Sr-90.

Air Particulate Filter Composites-- Gross Alpha Each weekly sample filter is individually counted for gross alpha activity, rather than analyzing a monthly composite of the filters, as described in Regulatory Guide 1.21.

Gaseous Effluents - Tritium Tritium releases during plant operation were less than detection levels. Since the plant was permanently shutdown in 1976, current tritium release levels are less than the release levels that occurred during plant operations. Therefore, no tritium samples were collected during this reporting period.

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Liquid Effluents - Sr-90 Batch releases may be analyzed individually, or composited and analyzed monthly, rather than analyzed as a quarterly composite as described in Regulatory Guide 1.21.

Average Enerqy For HBPP, calculations for the average energy of gaseous releases of fission and activation gases are not required to be performed or reported.

I. SUPPLEMENTAL INFORMATION A. Regulatory Limits

1. Gaseous Effluents

a. Noble Gas Release Rate Limit The radioactive noble gas release rate limit is based on concentration limits from 10 CFR 20, divided by an annual average dispersion factor for the sector with the least favorable atmospheric dispersion.

The applicable annual average dispersion factor is 1.0E-5 seconds per cubic meter.

b. Iodine Release Rate Limit Due to the long decay time since the Unit was shutdown, the license does not define an iodine release rate limit.

c. Particulate Release Rate Limit The radioactive particulate release rate limit is based on concentration limits from 10 CFR 20, divided by an annual average dispersion factor for the sector with the least favorable atmospheric dispersion. The applicable annual average dispersion factors for elevated releases and for ground-level releases are 1.OE-5 and 6.59E-3 seconds per cubic meter, respectively. The radionuclide mixture was determined to be 65%

Cs-1 37, 9% Co-60 and 4% Sr-90, 5% Fe-55, 11% Ni-63 and 6% Pu-241.

When both elevated and ground-level releases occur, the "percent of applicable limit" in Table 1 is the sum of the values for "percent of applicable limit" for each of the release paths.

2. Liquid Effluents

a. Concentration Limit Concentration limits for liquid effluent radioactivity released to Humboldt Bay are taken from 10 CFR 20.

B. Maximum Permissible Concentrations

1. Gaseous Effluents Maximum Permissible Concentrations for gaseous effluents are taken from 10 CFR 20, Appendix B, Table 2, Column 1.

2. Liquid Effluents Maximum Permissible Concentrations for liquid effluents are taken from 10 CFR 20, Appendix B, Table 2, Column 2.

C. Measurements and Approximations of Total Radioactivity

1. Gaseous Effluents - Elevated Release

a. Fission and Activation Gases All ventilation and system vents are routed to the Unit 3 stack. A continuous monitor equipped with a beta scintillator, with its response calibrated for Kr-85, monitors the gaseous activity released from the stack.

The "less than" value reported for Kr-85 is based on the estimated sensitivity of the stack Kr-85 monitor.

The estimated sensitivity of the stack Kr-85 monitor permits detection of Kr-85 at approximately 50% of the applicable LLD presented in the ODCM.

b. lodines Due to the long decay time since operation (shutdown July 2, 1976),

no detectable releases of radioactive lodines can be expected.

Therefore, neither the Technical Specifications nor the ODCM require that these radionuclides be monitored.

c. Particulates Radioactive particulates released from the plant stack are monitored by continuous sample collection on particulate filters. Filter papers are removed from the stack sampling system weekly, and are analyzed for the concentration of gamma-emitting nuclides (intrinsic germanium detector). All statistically significant gamma peaks are identified.

After decaying at least 7 days, the filters are analyzed for gross alpha radioactivity (internal proportional counter or scintillation counter).

Filters are composited monthly and analyzed monthly for Strontium-90 (the only radioactive Strontium present) and Americium-241 by alpha spectroscopy. The monthly composite results are averaged together to produce the quarterly composite result.

The estimated error of the reported particulate release values is based on uncertainty in sample flow rate, stack flow rate, detector calibration, and typical sample counting statistics.

The Minimum Detectable Activity (MDA) for all particulate filter samples was less than the applicable LLD presented in the ODCM.

Samples are assigned to calendar quarters as of the termination of the sample period. The amount of activity reported for a calendar quarter is the activity for the combined sample time, multiplied by the ratio of the length of the calendar quarter to the sample period.

2. Gaseous Effluents - Ground-level Release

a. Fission and Activation Gases All ventilation and system vents were routed to the Unit 3 stack during the report period. Refer to the discussion for elevated releases.

b. lodines All ventilation and system vents were routed to the Unit 3 stack during the report period. Refer to the discussion for elevated releases.

c. Particulates All ventilation and system vents were routed to the Unit 3 stack during the report period. Refer to the discussion for elevated releases.

3. Liquid Effluents

a. Batch Releases Water from contaminated plant systems was collected, filtered, treated with Cesium-specific ion-exchange media, and analyzed before discharge (on a batch basis) through the liquid radwaste process monitor. Analysis of weekly composite samples from the plant effluent canal did not detect any additional release of radioactive liquids during the report period.

Samples of liquid waste batches were analyzed for the concentration of gamma-emitting nuclides (intrinsic germanium detector). All statistically important peaks were identified. All batches were f,

analyzed for radioactive strontium (Sr-90), gross alpha, Ni-63 and tritium.

The error of the reported release values is estimated based on uncertainty in sample volume, batch volume, detector calibration, and typical sample counting statistics.

The MDA for all batch samples was less than the applicable LLD presented in the ODCM.

b. Continuous Releases There were no continuous liquid effluent releases during this report period.

D. Batch Release Statistics

1. Liquid

a. Num ber of batch releases ................................................... 6

b. Total time period for batch releases ................. 1.13E3 minutes

c. Maximum time period for a batch release ....... 3.41 E2 minutes

d. Average time period for a batch release ......... 1.89E2 minutes

e. Minimum time period for a batch release ....... 1.40E2 minutes

2. Gaseous

a. Num ber of batch releases .................................................. 0

b. Total time period for batch releases ................................... N/A

c. Maximum time period for a batch release .......................... N/A

d. Average time period for a batch release ............................ N/A

e. Minimum time period for a batch release ........................... N/A E. Abnormal Release Statistics

1. Liquid

a. Number of abnormal releases ...................... 0

b. Total activity released ....................................................... N/A

2. Gaseous

a. Num ber of abnorm al releases ............................................. 0

b. Total activity released ....................................................... N/A I1. GASEOUS AND LIQUID EFFLUENTS A. Gaseous Effluents Table 1 summarizes the total quantities of radioactive gaseous effluents.

Table 2A presents the quantities of each of the nuclides determined to be released from the stack (elevated release point). Table 2B presents the quantities of each of the nuclides determined to be released by other routes (ground level release points).

B. Liquid Effluents Table 3 summarizes the total quantities of radioactive liquid effluents. Table 4 presents the quantities of each of the nuclides determined to be released.

The quantity of radionuclides released in 2007 is similar to 2006, but higher than in previous years. The increase in the activity was due to the breach in the resin transfer line from the spent fuel pool demineralizer to the resin disposal tank. This breach resulted in resin being spilled into the offgas tunnel and rainwater in-leakage to the tunnel transporting the contamination into the liquid radioactive waste system. There was no unmonitored release of radioactivity from this incident.

The higher quantities of radionuclides discharged did not exceed the requirements of the ODCM with regard to effluent concentration limits or offsite doses.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 1 GASEOUS EFFLUENTS - SUMMATION OF ALL RELEASES Units First Second Third Fourth Est. Total Quarter Quarter Quarter Quarter Error, %

A. Fission & Activation Gases

1. Total release Ci <5.83E1 <5.83E1 <5.83E1 <5.83E1 3.20E1

2. Average release rate pCi/sec <7.41E0 <7.41E0 <7.41E0 <7.41E0

3. Percent of applicable limit  % <1.06E-2 <1.06E-2 <1.06E-2 <1.06E-2

4. Applicable limit pCi/cc 7.OOE-7 7.OOE-7 7.OOE-7 7.OOE-7 B. Particulates

11. Total release Ci <3.64E-06 <4.29E-06 <3.53E-06 <3.28E-06 3.60E1

2. Average release rate uCi/sec <4.30E-07 <5.46E-07 <4.48E-07 <4.51E-07

3. Percent of applicable limit  % <3.47E-06 <4.40E-06 <3.62E-06 <3.64E-06

4. Applicable limit pci/cc 1.24E-10 1.24E-10 1.24E-10 1.24E-10

5. Gross alpha radioactivity Ci <9.64E-08 <7.75E-08 <1.08E-07 <1.18-07 Note: The < symbol used in this table means that a majority of the measurements contributing to the result were less than the Minimum Detectable Activity (MDA) for the analyses. *Data for individual nuclides combines detected and non-detected results as if all values were detected. The < symbol is applied if less than 50% of the combined value is made up of detected results. When combining detected and non-detected results for different nuclides (e.g. activity totals of multiple nuclides),

values with the < symbol are ignored (i.e. treated as zero). When combining non-detected results for different nuclides (e.g. activity totals of multiple nuclides, when none were detected), all values with the < symbol are used.

If the total release for a period is determined to be a "less than" value, the limits are based on analytical results obtained in November, 2005, the mixture was determined to be 65% Cs-137, 90 /q Co-60 and 4% Sr-90, 5% Fe-55, 11% Ni-63 and 6% Pu-241.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 2A GASEOUS EFFLUENTS - ELEVATED RELEASE - NUCLIDES RELEASED Continuous Mode Nuclides Released Unit First Second Third Fourth Quarter Quarter Quarter Quarter

1. Fission Gasses Krypton-85 Ci <5.83E1 <5.83E1 <5.83E1 <5.83E1 Total for period Ci <5.83E1 <5.13E1 <5.83E1 <5.83E1

2. Particulates Cobalt-60 Ci <1.02E-06 <1.76-06 <1.02E-06 <9.09E-07 Strontium-90 Ci <1.37E-07 <1.23E-07 <1.75E-07 1.48E-07 Cesium-137 Ci <7.23E-07 6.89E-07 <7.33E-07 <5.69E-07 Am-241 Ci <1.76E-06 <1.72E-06 <1.60E-06 <1.65E-06 Total for period Ci <3.47E-06 <4.29E-06 <3.62E-06 <3.28E-06 Note: The < symbol used in this table means that a majority of the measurements contributing to the result were less than the Minimum Detectable Activity (MDA) for the analyses. Data for individual nuclides combines detected and non-detected results as if all values were detected, but the < symbol is applied if less than 50% of the combined value is made up of detected results. When combining detected and non-detected results for different nuclides (e.g. activity totals of multiple nuclides), values with the < symbol are ignored (i.e. treated as zero). When combining non-detected results for.different nuclides (e.g. activity totals of multiple nuclides, when none were detected), all values with the <

symbol are used.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 2B GASEOUS EFFLUENTS - GROUND-LEVEL RELEASES NUCLIDES RELEASED Continuous Mode, _

Nuclides Released Unit First Quarter Second r

Quarter Third Quarter Fourth Quarter

1. Fission Gasses Krypton-85 Ci N/A N/A N/A N/A Total for period Ci N/A N/A N/A N/A

2. Particulates Cobalt-60 Ci N/A N/A N/A N/A Strontium-90 Ci N/A N/A N/A N/A Cesium-137 Ci N/A N/A N/A N/A Americium-241 Ci N/A N/A N/A N/A Total for period Ci N/A N/A N/A N/A Note: N/A - There were no ground level gaseous effluents during the report period.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 3 LIQUID EFFLUENTS - SUMMATION OF ALL RELEASES First Second Third Fourth Est. Total Units Quarter Quarter Quarter Quarter Error, %

A. Fission & Activation Products

1. Total release (not including tritium, gases, alpha) Ci 2.47E-03 5.75E-04 0 2.63E-04 1.00E1

2. Average diluted ptCi/ml 9.87E-11 3.12E-11 0 1.05E-11 concentration

3. Percent of applicable limit  % 1.71E-02 5.71E-03 0 1.57-03

4. Applicable limit pCi/ml 5.78E-07 5.46E-07 0 6.66E-7 B. Tritium

1. Total release Ci 1.61E-04 7.25E-06 0 5.88E-05 1.50E1

2. Average diluted ptCi/ml 6.42E-12 3.93E-13 0 2.35E-12 concentration

3. Percent of applicable limit  % 6.42E-07 3.93E-08 0 2.35E-07

4. Applicable limit gCi/ml 1.OOE-03 1.OOE-03 0 1.OOE-03 C. Gross Alpha Radioactivity

1. Total release Ci 4.90E-06 5.36E-08 0 8.22E-07 1.OOE1 D. Volume of waste released Liters 9.74E+04 2.59E+04 0 2.54+04 3.OOEO (prior to dilution)

E. Volume of dilution water Liters 2.51E+10 1.84E+10 12.55E+10 2.51 E+1 0 1.50E1 Notes: The < symbol used in this table means that a majority of the measurements contributing to the result were less than the Minimum Detectable Activity (MDA) for the analyses. Data for individual nuclides combines detected and non-detected results as if all values were detected, but the < symbol is applied if less than 50% of the combined value is made up of detected results. When combining detected and non-detected results for different nuclides (e.g. activity totals of multiple nuclides),

values with the < symbol are ignored (i.e. treated as zero).

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 4 LIQUID EFFLUENTS - NUCLIDES RELEASED Batch Mode Nuclides Released Unit First Second Third Fourth Quarter Quarter Quarter Quarter Strontium-90 Ci 1.81 E-03 4.79E-04 0 1.32E-04 Cesium-137 Ci 6.59E-04 9.55E-05 0 1.30E-04 Cobalt-60 Ci 3.27E-06 3.73E-07 0 5.55E-07 Americium-241 Ci <1.44-05 <3.16E-06 0 <3.04E-06 Nickel-63 Ci 1.55E-04 8.52E-05 0 1.54E-05 Tritium Ci 1.61 E-04 7.25E-06 0 5.88E-05 Europium-155 Ci 1.03E-06 0 0 0 Alpha Emitters Ci 4.90E-06 5.36E-08 0 8.22E-07 Total for period Ci 2.79E-03 6.67E-04 0 3.38E-04 Continuous Mode Nuclides Released Unit First Second Third Fourth Quarter Quarter Quarter Quarter Strontium-90 Ci N/A N/A N/A N/A

• Cesium-137 Ci N/A N/A N/A N/A Cobalt-60 Ci N/A N/A N/A N/A Americium-241 Ci N/A N/A N/A N/A Total for period Ci N/A N/A N/A N/A Notes: The < symbol used in this table means that a majority of the measurements contributing to the result were less than the Minimum Detectable Activity (MDA) for the analyses. Data for individual nuclides combines detected and non-detected results as if all values were detected, but the < symbol is applied if less than 50% of the combined value is made up of detected results. When combining detected and non-detected results for different nuclides (e.g. activity totals of multiple nuclides), values with the < symbol are ignored (i.e. treated as zero).

Ill. SOLID RADIOACTIVE WASTE Table 5 summarizes the disposal of solid radioactive waste made during the report period.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 5 SOLID WASTE AND IRRADIATED FUEL SHIPMENTS A. Solid Waste Shipped Offsite For Burial Or Disposal

1. Type of Waste Unit 12 Month Estimated Total Error, Period  %

a. Spent resins, filter sludges, Cubic Meter 0 N/A evaporator bottoms, etc. Ci 0 N/A

b. Dry compressible waste, Cubic Meter 94.4 1.OOE1 contaminated equipment, etc. Ci 1.29 5.60E1

c. Irradiated components, Cubic Meter 11.1 1.0OE1 control rods, etc. Ci 580 5.60E1

d. Other (soils, demolition debris Cubic Meter 348 1.OOE1 etc.)

Ci 0.311 5.60E1

2. Estimate of major nuclide Unit Nuclide 12 Month Period composition (by type of waste)

b. Dry compressible waste,  % H-3 6.83E-2 contaminated equipment, etc.  % C-14 3.49E-2

% Fe-55 5.14E0

%._Co-60 1.83E1

% Ni-59 1.35E-1

% Ni-63 3.45E1

% Sr-90 1.30E0

% Tc-99 2.83E-1

% 1-129 3.78E-2

% Cs-137 3.35E1

% U-234 1.90E-3

% U-238 1.84E-3

% Pu-238 2.78E-1

% Pu-239 3.32E-1

% Pu-241 4.20E0

% Am-241 1.53E-0

% Cm-243 3.19E-1

% Cm-244 1.85E-4

c. Irradiated components,  % H-3 4.51 E-2 control rods, etc.  % C-14 2.05E-1

% Fe-55 1.15E-1

% Co-60 5.71E1

% Ni-59 3.35E-1

% Ni-63 4.19E1

% Sr-90 1.19E-4

% Zr-93 1.23E-1

% Nb-94 6.01 E-3

% Tc-99 3.86E-4

% Sb-125 1.12E-1

% Cs-137 7.83E-4

% Pu-238 2.69E-4

%Pu-239 7.02E-5

% Pu-241 3.58E-3

% Am-241 5.84E-4

% Cm-243 9.81E-4

% Cm-244 2.52E-6

d. Other (Processed Waste) % H-3 4.93E-0

% C-14 1.16E-1

% Fe-55 8.59E-1

% Co-60 8.88E-1

% Ni-59 9.90E-3

% Ni-63 2.31 EQ

% Sr-90 5.43E-1

% Tc-99 6.85E-2

% Cs-137 8.85E1

% U-234 2.39E-1

% U-238 2.30E-1

% Pu-238 4.29E-2

% Pu-239 5.05E-2

% Pu-241 9.52E-1

% Am-241 2.35E-1

% Cm-244 2.26E-2 HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 5 - Continued SOLID WASTE AND IRRADIATED FUEL SHIPMENTS

3. Solid Waste Disposition Number of Mode of Destination Shipments Transportation ___________

22 Truck Energy Solutions, LLC 3 Truck Barnwell Waste

_________________________________ ____________Management Facility IV. RADIOLOGICAL IMPACT ON MAN A comparison of calculated doses from various paths has shown that the offsite doses are primarily due to direct radiation and to the consumption of aquatic foods. Maximum doses to individuals (for the maximally exposed organs and age groups) are summarized in Table 6. These doses comply with 40 CFR 190 as there are no other uranium fuel cycle facilities within 8 km of the Humboldt Bay Power Plant.

A. Doses to the average individual in the population from all receiving-water-related pathways were calculated for detected releases, based on the guidance of Regulatory Guide 1.109. The highest results were less than 0.01 mrem/yr (total body) for the Adult age group, and less than 0.030 mrem/yr for the bone of the Adult age group.

These doses are well below the 10 CFR 50, Appendix I numerical guidelines for limiting effluents as low as is reasonably achievable (ALARA) (3 mrem/yr to the total body and 10 mrem/yr to any organ).

B. Total body doses to the average individual in the population from gaseous effluents to a distance of 50 miles from the site are not calculated, but this dose is less than the total body dose to an average individual present at the maximally exposed location. For an average individual at the maximally exposed location, the total body dose (calculated with the same dispersion and deposition parameters as were used to calculate maximum exposure) was less than 0.001 mrem/yr.

This maximum calculated dose is well below the 10 CFR 50, Appendix I numerical ALARA guidelines (10 mrem/yr for gamma radiation and 20 mrad/yr for beta radiation from noble gases and 15 mrem/yr to any organ from tritium and radionuclides in particulate form).

C. Total body doses (to the average individual in unrestricted areas from direct radiation from the facility) are based on TLD results of,stations at the site boundary, using the shoreline occupancy factors given in Regulatory Guide 1.109 for the highest average potential individual (Teen age group). For this group, direct radiation would result in an exposure of 0.01 mrem/yr.

This maximum potential dose is well below the 10 CFR 20.1302(b)(2)(ii) limit of 50 mrem/yr from external sources necessary to demonstrate compliance with the 10 CFR 20.1301 dose limit for individual members of the public.

HUMBOLDT BAY POWER PLANT ANNUAL RADIOACTIVE EFFLUENT RELEASE REPORT 2007 TABLE 6 RADIATION DOSE FOR MAXIMALLY EXPOSED INDIVIDUALS Dose, milli-rem First Second Third Fourth Annual Dose Source Quarter Quarter Quarter Quarter Total Liquid Effluents Water-related Pathways (1) <0.01 (5) <0.01 (5) <0.01 (5) <0.01 (5) <0.01 (5) 0.02 (6) <0.01 (6) <0.01 (6) <0.01 (6) <0.03 (6)

Airborne Effluents Particulates (2) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7) 0.00 (7)

Noble Gases (3) N/A N/A N/A N/A N/A Direct Radiation (4) <0.01 <0.01 <0.01 <0.01 0.01 Notes

1. Maximum total body and organ doses to individuals in unrestricted areas from receiving-water-related exposure pathways were calculated from the average concentrations of liquid releases detected during the report period, following the applicable portions of Regulatory Guide 1.109 and NUREG-4013.

2. Maximum total body and organ doses to individuals in unrestricted areas from airborne-particulate-related exposure pathways were calculated from the average concentrations of airborne particulate releases detected during the report period, following the applicable portions of Regulatory Guide 1.109 and NUREG-4013.

3. Total body and skin doses to potentially exposed individuals located at the point of maximum offsite ground-level concentrations of radioactive gaseous effluents were not calculated because there were no detected releases of radioactive noble gases, and because the total body doses would be less than 0.005 milli-rem/yr at the level at which the releases could be detected.

4; Total body doses (to the maximum individual in the population) are based on TLD results of stations at the site boundary, using the shoreline occupancy factors of Regulatory Guide 1.109 for the maximum potential individual (Teen age group).

5. Total body (Adult age group).

6. Bone (Adult age group).

7. For stack releases, a majority of the results were "not detected", resulting in a total activity considered "not detected", for which no dose is calculated.

V. CHANGES TO THE OFFSITE DOSE CALCULATION MANUAL (ODCM)

The ODCM was revised two times during the report period. The changes maintained the level of radioactive effluent control and dose commitment required by regulation, and did not adversely affect the accuracy or reliability of effluent, dose or setpoint calculations.

Revision 13 to the ODCM was reviewed by the Plant Staff Review Committee (PSRC) on 3/1/07, approved by the Plant Manager on 3/1/01, and became effective on 3/2/07. The changes in this revision were to reflect the installation of a new Radioactive Liquid Effluent Monitoring System (RLEMS) that replaced the non-repairable existing RLEMS. As a result, the ODCM was revised to:

• Reflect an updated RLEMS calibration factor obtained during the baseline calibration of the new RLEMS.

" Incorporate a new RLEMS setpoint during normal operations, identified during calculations associated with the radiological calibration of the new system.

" Lower the allowable background of the RLEMS to allow meeting the requirements of Specification 2.1.

• Table 1-1 has been modified to better reflect the effect of dilution on the alarm setpoints.

The revision also reflects a change in nomenclature to more closely follow the ODCM. (The RLEMS has been identified in the past as the Process Monitor, Liquid Process Monitor, Liquid Effluent Monitor, Liquid Process Monitoring System, and other similar names).

Revision 14 to the ODCM was reviewed by the Plant Staff Review Committee (PSRC) on 12/15/05, approved by the Plant Manager on 8/23/07, and became effective on 9/6/07. This revision to the ODCM incorporated the following changes:

• Table 2 During a previous revision (REV 12) to the ODCM the Ground Water sample frequency, locations, and number of samples were inadvertently deleted. This information was re-inserted and not edited.

" Table 2 Footnote (b) was deleted. This footnote unclearly explained how each phosphor in a TLD was considered to be a separate dosimeter and also stated that film badges should not be used. The number of phosphors in a TLD has nothing to do with this table. Phosphors are used to calculate TLD dose and phosphors are averaged. This is discussed in the annual reporting of these doses in the Annual Radioactive Effluent Release Report. Since film badges are no. longer used, reference to them warrants removal.

" Table 2 TLD Station number 33 was deleted because changing TLDs in the winter is a safety hazard due to mud and swampy conditions and.

When the new generating plants are installed, more mass will exist between Unit 3 and the TLD, thus shielding the TLD. Additionally, since the Unit 3 unfiltered exhaust stack was replaced with.a HEPA filter exhaust, the TLD is not subject to radiation caused by fallout of plant radionuclides. This station is not an ODCM required TLD station. Trends from 1990 to 2006 for three TLD stations indicated no increase in background with exposure deviations within the 95% confidence levels based on the mean values for the 1990s. These TLD stations are: Station 14, at the South Bay School parking lot, and, T14 and T15, located on the plant south Owner Controlled Area fence between Unit 3 and Station 33.

This station is a HBPP elective station and is not one of the four ODCM required stations.

• Figure 2 The locations of the following stations were deleted since they were not specified in table 2-10: 13, 16, 30, 33, & 35.

• Figure 2 The locations of the following stations were deleted since they were not specified in table 2-10: 20 & 23 Figure 2 The TLD location at station 5 was deleted since it is not specified in Table 2-10 VI. CHANGES TO THE PROCESS CONTROL PROGRAM (PCP)

There were no changes to the Process Control Program during the report period.

VII. CHANGES TO RADIOACTIVE WASTE TREATMENT SYSTEMS There were no changes to the Radioactive Waste Treatment Systems during the report period.

VIII. INOPERABLE EFFLUENT MONITORING INSTRUMENTATION The radioactive liquid waste process monitor was inoperable for a period of 30 days or more during this reporting period.

The radioactive liquid waste process monitor was declared inoperable on February 22, 2006 due to the failure of STP 3.21.4 "Quarterly Liquid Radwaste Process Monitor Source Check and Channel Functional Test". The reason for the failure was the degradation of the electronics which resulted in the inability to properly adjust and maintain the gain of the system.

A notification was written to repair or replace the monitor on March 10, 2006.

After attempts to repair and replace the components of the radioactive liquid waste process monitor were unsuccessful, a new monitoring system was ordered on June 20, 2006. The new monitor was received on .November 2, 2006. The system was tested, installed, calibrated and declared operational on March 2, 2007.

All radioactive liquid discharges performed while the process monitor was inoperable were conducted in accordance with the ODCM requirements for such discharges.