a bat 3 Ly NOV 15 1973 Department of Energy Nevada Operations Office PO. Box 14100 Las Vegas, NV 89114 s L. Joe Deal, HQ (EV-123) ay: W. Wachhotz ~eF “ LA Office of Environment, HQ (EV~212) TRANSURANICS DATA, ENEWETAK Over the past several weeks, NV (ERSP) has been evaluating a systematic error in the in situ measurement of Americium at Enewetak. This error derives from the improper use of a soil composition which is not representative of the actual. In calculating the attenuation of 60 KEV energy, the error is significant (in the range of 20-25%). Before introducing a wholesale correction in the Enewetak transuranics data base, ERSP is evaluating other uncertainties, both systematic and random. This may require a modest amount of additional fieid work. Assuming that the current 20-25% (low) estimate is verified, all Imp transuranics numbers will require adjustment. At first look, it appears that this will place the certification of the following islands technically in question: Irene, Janet, Kate, Mary, Olive, Sally. On Janet (Engebi) for example, a total of twelve quarter hectare-sized areas cannot now be certified to be below the 40 pCi/gm residential standard. The highest average reading in any such quarter hectare will be somewhere between 40 and 50 pCi/gm. The total affected area (that which may exceed the standard) will be approximately 2.5% of the total island area; the island average, however, will remain well below 25 pCi/gm. This reflects the conservatism wnicn has been built into ERSP application of the 40-80-1600 standards. As it turns out, the technicality of island-by-island certification remains ambiguous enough to accommodate even the current situation. This is because the terms "Residential", "Agricultural" and "Food Gathering", recommended for adoption by the Bair Committee have not been precisely defined. I drafted a definition paper (copy enclosed) which was telecopied to Tom McCraw on Jan 30, 1978. I later (June 12, 1979) telecopied it to you*for comment and/or staffing for approval. It took the form of a “strawman" of a DOE (Liverman) memo to me and to DOI and DNA. Since that strawman has not been acted upon, our certification document remains ambiguous in that it refers in Par III to the K Bul wachkhela seas Poe tee 7 ee iCe ep mere ge - mom, Tee ae