- 18 FRC, ICRP, and NCRP have all taken the position that there can be different guides with different numerical values for different circum- stances. This is one reason why it is difficult for standards agencies to develop standards applicable to a broad range of circumstances. This is also why such guidance is often developed on an Ad Hoc basis. The Task Group 40-400 pCi/g and the 1 pCi/g cited by Dr. Martell are both examples of Ad Hoc guides for plutonium in soil developed for a completely different purpose and for very different conditions. in both guides are considerations of what may be feasible. both is the assumption that neither is absolutely safe. Inherent Inherent in Neither of the guides should be considered as standards, It is not feasible to plan operations such as Enewetak cleanup on the basis of what may be learned in the future that would warrant changing standards. Likewise, application of current Federal Regulations containing basic radiation protection philosophy, practice, and standards cannot be too much influenced by a contrary State Health Department "interim standard" devised for a unique set of circumstances. Assuming that basic standards can be met, it is reasonable to assume ~ that the guide selected for each set of circumstances involving pro- tection of people from radiation exposure would be the lowest level within the standard that is feasible, a level that is attainable without inordinate difficulties. This is the idea behind the "lowest practicable" concept. From a radiation exposure consideration, there is in fact little choice in the level of procection that can be provided the Enewetak people, The choices for cleanup degree at Enewetak are limited in one