ML20066C763
| ML20066C763 | |
| Person / Time | |
|---|---|
| Site: | Prairie Island  |
| Issue date: | 01/04/1991 |
| From: | Parker T NORTHERN STATES POWER CO. |
| To: | NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM) |
| References | |
| NUDOCS 9101110133 | |
| Download: ML20066C763 (2) | |
Text
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f Northem States Power Company 414 Nicollet Mall Minneaoolis Minnesota $54011927 Telephone (612) 330 5500 January 4, 1991 U S Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 PRAIRIE ISLAND NUCLEAR GENERATING PLANT Docket Nos. 50-282 License Nos. DPR 42 50-306 DPR-60 Response to Open Item Inspection Reports No. 50 282/89007(DRSS) and 50 306/89007(DRSS)
In response to your letter of March 30, 1989, which transmitted Inspection Reports No. 282/89007 and 306/89007, the following information is offered.
Open Item The inspectors toured the air sampling stations around the plant and observed the licensee representative check the systems for operability (vacuum) and demonstrate the procedure for adjusting J
the constant flow regulators with a calibrated Rotameter. The inspectors noted a concern that, although each of the parts of the collection train was tested for cir in leakage, the train as a whole was not so tested by some procedure, such as blocking the face of the filter hold In addition, they noted that-the flow-rates drifted over the calibration period by as much as 25%, but that no corrections were made to the total volume sampled, or on the acceptable level of change. The licensee representative agreed to consider these concerns and to submit a letter to Region III on their resolution. This will be followed under Open Items No. (50-282/89007-04; 50-306/89007 04).
Response
Sampling Procedures for the Radiological Environmental Monitoring Program, 8 O which were prepared and controlled by Toledyne Isotopes Midwest Laboratory, j
were substantially revised on January 23, 1990 with many inputs from Northern States Power Environmental Regulatory Affairs Department field personnel.
An equation for calculating air volume and methods for leak test were included.
Theac procedures are now controlled by the Nuclear Radiological Services Department.
9101110133 910104 PDR ADOCK 05000282 1
0 PDR
Northem States Fower Company USNRC January 4, 1991 Page 2 The responsibility for sample collection was transferred from the l
Environmental Regulatory Affairs Department to the Nuclear Radiological Services Department on January 1,1990.
All the Radiological Environmental Monitoring Program responsibilities were consolidated within the Nuclear Radiological Services Department. A former Radiation Protection Specialist from the Prairie Island Nuclear Generating Plant, was added to the Nuclear Radiological Services Department on March 1: 1990 to fulfill this new responsibility.
Since assuming the responsibility for sample collection, the Nuclear Radiological Services Department has made significant improvements to the air sampling stations and how they are tested.
Old clam shell sample holders were replaced with new in line sample holders.
Every sample change, a portable flow-rate meter is connected via a quick connector located in the sampling trafn upstream of the in line holder.
The flow rate is then recorded.
The inlet of the sampling train is blocked off to check for any leakage on the system. The system is also checked by verifying that the vacuum is drawn down to the vacuum breaker setting.
This method is similar to the monthly calibration procedure with the exception that during the monthly calibration the vacuum is drawn to the maxir*um obtainable level.
The problem of drifting flow rates was resolved by taking a flow-rato reading at the time of installation of the sample holder assembly and another at the time of its removal, the average of these two flow rate readings is used to l
calculate the total volume.
I The improvements in the admfnistration of the air sampling program and the modifications to the air sampler hardware and test methods should a~ddress all of the concerns expressed in the subject open item.
Picase contact us if you have any questions related to this response.
1 l
1 lThomasMParker)16f+ Manager Nuclear Support Services c: L. Robert Greger, NRC Region III Regional Administrator III, NRC Senior Resident inspector, NRC NRR Project Manager, NRC J E Silberg}}