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Insp Rept 50-395/86-22 on 861120-21 & 1216.Violations Noted: Exposure of Extremities of One Individual in Excess of 10CFR20.201(a) Limits & Failure to Have Procedure Addressing Skin Dose Calculation Due to High Levels of Contamination
	ML20207T502
Person / Time
Site:	Summer
Issue date:	01/02/1987
From:	Collins T, Hosey C; NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
To:	;
Shared Package
ML20207T497	List: ML20207T496; ML20207T502;
References
	50-395-86-22, IEIN-86-023, IEIN-86-23, NUDOCS 8703240077
	Download: ML20207T502 (7)
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g4 4004 UNITED STATES

cf , Io,, NUCLEAR RE20LATORY COZZlSSION

$ o REGION il

5 -g 101 MARIETTA STREET, N.W., SUITE 2900

~t ATLANTA. GEORGIA 30323

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Report No.: 50-395/86-22

Licensee: South Carolina Electric and. Gas Company

Columbia, SC. 29218

Docket No.: 50-395 . License No.: NPF-12

Facility Name: Sunvrer

Inspection Conducted: November 20-21, 1986 and December 16, 1986

Inspector:

T. R. Collins

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Date Signed

Approved by: hM, e

C. M. Hoseyf, W ction Chief

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Date Signed

Division of Radiation. Safety and Safeguards

SUMMARY

Scope: This special, unannounced inspection was in the area of followup of an

apparent exposure to the extremities of a licensee employee in excess of

10CFR20.101(a) limits.

Results: Two violations were identified: (1) Exposure to the extremities of one

individual in excess of 10 CFR 20.101(a) limits; and (2) failure to have an

adequate procedure to address skin dose calculation due to high lovels of skin

contamination.

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F703240077 870312

PDR ADOCK 05000395

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REPORT DETAILS

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1.- Persons Contacted

Licensee Employees

D. A Nauman, Vice President, Nuclear Operations .

J. L. Skolds, . Deputy Director, Operations -and Maintenance

J. Connelly, Director, Nuclear Services

W. A.~ Williams, Jr.. .Special Assistant, Nuclear Operations

A. R. Koon, Jr. , Manager, Technical- Support

M. D. Quinton, Manager, Maintenance Services

- *F. J. Leach, Manager, Quality Assurance

J.^ F. Sefic, Manager, Nuclear Security

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W. R. Baehr, Manager, Corporate Health Physics and Environmental Programs-

M. B. Williams, Group Manager, Nuclear Regulatory and Development Services

M. N. Browne, Group Manager, Technical and Support Services

J. Cox, Associate Manager, Health Physics

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W.;R. Higgins, Associate Manager, Regulatory Compliance

E. M. Hollins,. Corporate Health Physics.

R. Bouknight, Nuclear Licensing

J. Knox, Nuclear Technical Instructor

Other-licensee employees contacted included four technicians, one mechanic,

. security force members, and office personnel.

Nuclear Regulatory Commission

P. Hopkins, Senior Resident Inspector

Attended exit interview

-2. Exit Interview

The inspection scope and findings were summarized on November 21, 1986,.with

those persons indicated in Paragraph 1 above. Two violations were discussed

in detail (Paragraph 4): (1) personnel exposure in excess of

10 CFR 20.101(a) limits; and (2) failure to have an adequate procedure to

address skin dose calculations due to high levels of skin contamination.

The licensee acknowledged the -inspection findings and took no exceptions.

The licensee did not identify as proprietary any of the materials provided

to or reviewed by the inspector during this inspection.

3. Licensee Action on Previous Enforcement Matters

This subject was not addressed in the inspection.

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4. PersonnelOverexposureInvestigation(93700)_

On November 19, 1986, the licensee . notified Region II that a licensee

. employee had apparently received an exposure to the skin of his extremities

greater than 75 rems, which is in excess of the quarterly extremity limit of

18.750 rems specified in 10 CFR 20.101(a).. The licensee stated that the

exposure was apparently caused by a single particle that was discovered on

the worker's skin when-he exited the Radiation Controlled Area (RCA).

Through discussions-with licensee representatives, the inspector determined

that on November 7,1986, an electrician worked on a control panel for the

overhead crane in the fuel handling building. The fuel handling building

was a clean area where no protective clothing was required. The individual

~ exited the RCA after performing work on the crane and when he entered the

portal monitor, the alarm was set off. Health Physics personnel determined ,

that the individual was contaminated on the back of his right hand by using

an RM-14 portable frisker with a hand-held probe; however, the Health

-Physics Specialist did not quantify the amount of contamination present with

the RM-14 because the contamination exceeded 10,000 counts per minute (cpm).

A survey was then performed using an Eberline R0-2 beta-gamma survey meter

which indicated that the contamination was 1.0 millirem per_ hour gatma

(window closed), and 2.0 rads per hour beta (window open) using a correction

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factor of 2 for beta activity.

I ' The worker was decontaminated by wiping the contaminated area with warm

water _ and soap. Health physics (HP) personnel did not retain the

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' contaminant for further analysis. The HP Specialist providing assistance

j' during decontamination did not realize that this high level skin

j contamination could result in an apparent exposure to the extremities

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greater than the allowable limits specified in 10 CFR 20.101(a).

i Techn'ical Specification 6.11 requires in part that procedures for personnel

radiation protection shall be prepared consistent with the requirements of

The inspector reviewed the licensee's Administrative

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i 10 CFR 20.

Procedure HPP-405, Personnel Decontamination, and concluded that the

l procedure was inadequate to address skin dose calculations due - to high

! levels of skin contamination. The HP Specialist who provided assistance in

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this event calculated a 70-minute skin exposure of only 10 millirem based on

10,000 counts per minute as was required by Procedure HPP-405, Personnel

Decontamination. Failure to have a procedure which adequately addressed the

proper calculations for skin exposures due to high levels of skin

! contamination and notification of licensee management of significant

L contamination events was identified as an apparent violation of Technical

Specification 6.11(50-395/86-22-01).

In discussions with licensee management, the inspector determined that

, licensee management was not apprised of the exposure until November 19,

j 1986. The reason for the event not being adequately evaluated on the day of

i the occurrence was due to the HP Supervisor not recognizing that the HP

( Specialist, who prepared the Personnel Contamination Report, had made

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several errors in documenting the survey results. Initially "2 mrad" was

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documented on the Personnel Contamination Report, however, the HP Specialist

retrieved the report and struck through the "m" in the "2 mrad" entry. The

supervisor believed that the strike through was for the entire "2 mrad"

entry. . However, _ once licensee management became aware of the exposure,

Region II was notified as required by 10 CFR 20.403. The licensee also

promptly submitted a Licensee Event Report (LER).

The inspector _ reviewed detailed survey results performed by the licensee of

the. area where the individual was working both prior to the event and

afterwards. All survey results revealed that the contamination levels were

within administrative guidelines. The licensee has been unable to detemine

where the contamination that caused the dose originated. Based on the R0-2

survey results of 2 rad /hr beta and 1 mrem /hr gansna it appears that the

contamination may be a beta emitter.

10 CFR ?0.101(a) states that no licensee shall possess, use, or transfer

licensed material in such a manner as to cause any individual in. a

restricted area to receive in any period of one calendar quarter from

radioactive material and other sources of radiation a total occupational

dose in excess of 18.75 rems per calendar quarter to the hands and forearms;

feet and ankles (extremities). During the time of the inspection, licensee

dose calculations revealed that the exposure to the skin of the extremities

was greater than 75 rems. The licensee compiled all available information

and forwarded it to several recognized experts in the field of health

physics to evaluate the dose from the point source contamination and the

resulting biclogical effects. The resultant calculated dose range was

determined by the-licensee's consultants to be 286 to 420 rems. These_ doses

were obtained using guidance of Inspection and Enforcement Notice

(IEN) 86-23, Excessive Skin Exposures Due to Contamination with Hot

Particles, and by calculating the hypothetical absorbed dose to an

infinitely thin ~ planar slab of tissue located at a depth of 7 mg/cm2 and

having a surface area of I cmr. Utilizing the philosphy of ICRP-26, a

consultant estimated the exposure to be approximately 400 rads. The

licensee report of the event (LER 86-18) stated that the individual's dose

record was being updated to reflect dose to the extremity of 42.8 rems.

This value was based on guidance contained in the proposed revision of

10 CFR 20.

NRC regulations are not currently based on ICRP-26 philosphy, but are based

on NBS Handbook 59. Using this methodology and the guidance in Information

Notice 86-23, the apparent dose to the skin would be approximately 420 rems.

Failure to control licensed material in such a manner as to limit the

occupational dose to an individual's extremities to less than 18.75 rems per

~ calendar quarter was identified as an apparent violation of 10 CFR 20.101(a)

(50-395/86-22-02).

5. Enforcement Conference

An Enforcement Conference was held at NRC Region II on December 16, 1986, to

discuss the apparent exposure of a licensee employee in excess of the

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- quarterly exposure limits for the extremeties given in 10 CFR 20.101(a).

The following persons were in attendance:

-a. South Carolina Electric and Gas Company

D. A. Nauman, Vice President, Nuclear Operations

0. - S. Bradham, Director, Nuclear Plant Operations

J. G. Connelly, Director, Nuclear Services

M. N. Browne, Group Manager, Technical Support

4 M. B. Williams, Group Manager, Nuclear Regulatory and Developmental

Services

W. R. Baehr, Manager of Corporate' Health Physics and Environmental

Programs

L. A. Blue, Manager of Support Services

W. A. Williams, Jr., Special Assistant, Nuclear Operations

J. Auxier, Consultant to South Carolina Electric and Gas Company

J. R. Frazier, Consultant to South Carolina Electric and Gas Company

b .' Nuclear Regulatory Commission

M. L. Ernst, Deputy Regional Administrator

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L. A. Reyes, Deputy Director, Division of Reactor Projects (DRP)

J. P.- Stohr, Director, Division of Radiation Safety and Safeguards

(DRSS)

G. R. Jenkins Director, Enforcement and Investigation Coordination

-Staff

D. M. Collins, Chief,- Emergency Preparedness and Radiological

Protection Branch, DRSS

C. M. Hosey, Chief, Facilities Radiation Protection Section, DRSS

T. R.. Collins, Radiation Specialist, DRSS

H. C. Dance Chief, Reactor Projects Section IB, DRP

P. Hopkins, Resident Inspector, Summer

L. P. Modenos, Project Engineer, Reactor Projects Section 18, DRP

B. Uryc, Enforcement Specialist

L. Trocine, Enforcement Specialist

During the meeting, licensee personnel presented discussions of the sequence

of events leading up to the personnel exposure in question and detailed the

corrective steps taken and plans to preclude recurrence of such exposures.

A copy of the slides used. during the presentation is included as

Attachment 1 to this report. Licensee representatives stated that their

skin exposure calculations were based on several very conservative

assumptions and that there are now more technically sound methods of

determining skin dose than those used as the basis of the regulations.

NRC personnel stated that the NRC technical staff would carefully review and

evaluate the information presented by the licensee.

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6. Staff Evaluation of Licensee Position Taken in the Enforcement Conference

In the Enforcement Conference on December 16, 1986, the licensee discussed

issues related to the methods and assumptions for determining the dose to

the employee's extremities.

Licensee representatives discussed the technical basis for the regulations,

focusing on the difference between the bases for 10 CFR 20 and current

recommendations of international radiation protection groups. The bases for

current NRC regulations, NBS Handbook 59, specified that the area of

interest for such exposures is 1 cmr at a depth of 7 mg/100 cm2

Licensee representatives stated that International Commission on

Radiological Protection in ICRP-26 specifies that estimates should be made

of the average dose equivalent over 1 cm2 in the area of highest dose

equivalent and comparisons made with the dose equivalent limit, except when

the dose distribution is extremely non-uniform. Licensee representatives

stated that indications from this event led them to conclude the dose came

from a very small particle. This conclusion was based on the fact that they

could find no evidence of contamination in the areas where the man had

worked, and that they had found one such small particle on equipment :t

their facility previously. Licensee representatives noted that ICRP-26, for

extremely non-uniform dose distributions makes the following recommendation:

"If the dose distribution is extremely non-uniform, as is that from

very small particles in contact with the skin, the local distribution

of absorbed dose should be assessed and used to predict possible local

skin reactions. It is inappropriate, however, to relate such localized

absorbed doses to the absorbed doses corresponding to the dose

equivalent limit."

Licensee representatives stated that there were no indications of skin

reddening at the spot of exposure and that the individual's hand had been

examined by a physician who detected no effects.

Licensee representatives noted that the dose assessment averaged over 10 cmr

as reconnended in the proposed 10 CFR Part 20 revision, would result in a

dose of 42.8 rems. Licensee representatives also noted that the proposed

( revision to 10 CFR Part 20 would, following the recommendation of ICRP-26,

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set the skin dose equivalent limit at 50 rems per year.

Licensee representatives noted that the dose to the very small volume of

tissue irradiated by a small particle of 76.6 uC1, would result in very high

t doses to most of the cells irradiated, causing cell death but very little

probability of damage to cells that could result in the potential for

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long-term effects. Licensee representatives stated that they had considered

recommending the excision of this small portion of the skin, but had

concluded that the risk to the individual from such a minor medical

procedure was in fact higher than the risk from any absorbed radiation dose.

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Licensee representatives also discussed their contamination containment and

reduction program and the actions taken in response to Information

Notice 86-23.

Licensee representatives also discussed corrective actions taken or underway

to prevent recurrence including:

- development of a procedure for identification and evaluation of such

skin exposures

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- comprehensive survey of the area where the worker most likely was

contaminated

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retraining of staff on skin contamination evaluations

NRC representatives noted that current regulations were based on NBS

Handbook 59 and that current policy for determination of skin dose was 1

outlined in IEN 86-23. This practice required dose assessment over 1 cm2 at (

a depth of 7 mg/cmr . Such assessment by the licensee showed 428 rads. NRC t{

representatives noted that the proposed 10 CFR Part 20 was not effective and \

should not be used to evaluate current doses.

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ML20207T502

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