Activity Report of TENORM Task Group10.

Problems to be Solved
The flow toward the NORM/TENORM solution could be summarized as following steps.

[Step 1]The Conceptual Understanding is Essential for a Stable Solution of NORM/TENORM
Problem
In case of the practice, like radioactive waste disposal, the base is a dose limitation togeneral public as 1mSv/y based on ICRP Publ. 60. As a dose constraint for a practice ofradioactive waste disposal, the recommended value of 0.3 mSv/y is given in the ICRP Publ.
7710). But as a free release value for radio-nuclide contained consumer goods, an exemption
value; 10 µSv/y is used for a measure of safety. Nearly the same situation appears inIAEA-RS-G-1.7 as a clearance level for a big volume, but extremely low level radioactive
waste from a decommissioning of nuclear facilities.
On the other hand, in case of NORM/TENORM discussion, exclusion andintervention concepts are inevitable for making-up guideline of NORM/TENORM. The
exclusion is based on an uncontrollability of sources, and the intervention guidelines(1mSv/y: intervention exception level, 10mSv/y: intervention start line, 100 mSv/y:intervention obligation line) are based on ICRP Publ. 82 for the protection guideline under along term public exposure.
[Step 2]
Fact Finding of NORM/TENORM based on the Scientific Data
Generic information is important for the real understanding of nature and making up aclassification of radioactivity and radiation level for NORM/TENORM. These genericinformation are collected in UNSCEAR report under worldwide surveys. Data collection
based on the documents is also important for the purpose of incorporating an each region andcountry’s situation.
[Step 3]
Measurement of Radioactivity and Radiation
A specific data collection of radioactivity (Bq/g or MBq/t) and radiation（µSv/h ormSv/y）through real measurements is valuable. These on site measurements give us adirection to the next step.

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Activity Report of TENORM Task Group[Step 4]Characterization of NORM/TENORM and Categorization of Levels
Depending on a form of existence, a purpose of use and a level of radiation, acharacterization or a categorization is possible on NORM/TENORM. One side end has a strong
trend of exclusion for the reason of unamenability of control. On the other end has a strong
trend of practice for the reason of usual application as consumer’s goods. To these continuouschanging situations, Japanese radiation council has already given of 6 categories based on theconsideration of practice and intervention as mentioned before for the guideline ofNORM/TENORM.
[Step 5]
Indication of Countermeasures and Setting Regulations if necessary
Several countermeasures are conceivable; a simple shielding of stockyard, a soil
cover of repository site, a preparation of simple mask for the protection of workers. All ofthese are countermeasures for the extreme condition of NORN/TENORM. If necessary, aguideline, a regulation or a law should be prepared depending on the situations based on thecategorization by dose (Sv) or activity (Bq).
[Step 6]
Application to the Real Scene
The application of countermeasures based on the categorization should be easy tounderstand. For an administrative management, a checklist system listing requirements will
be helpful for an on-site application of these countermeasures.

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