I have seen values from draft EPA "do not cite, quote ..." docs that list Cs-137 + D at 0.7 pCi/g typical and ranges from 0.1 to 3.5 pCi/g paul charp (pac4@atsdto1.em.cdc.gov) ---------- I give. Will try the easy route. Where does one find typical values of Cs-137 concentration in soil. A little risk adds spice to life. slaback@MICF.NIST.gov