Major Max Toch Page 2 April 10, 1978 XRU-1 is a 2" slotted casing on the rim of the crater at the end of the same roadway containing ARU-3. It is marked with tape; I believe that the remains of a flag are attached or nearby. XRU-2a is about 20 m E. of ARU-3. It has 4" casing sleeves, and is marked with tape and a fiag. I believe it is slightly N.W. of the location indicated on the attached map. XRU-3 in a is the grass southernmost of the northern Runit wells, and vine covered open area lagoonward of the located road. It has 4" sleeve casings and is marked with tape and a flag. It is somewhat W. and siightly S. of the location indicated on the attached RRU-5 with is map, about tape, a 10 m from the flag, S.W. lip of the and has 4" sleeve casings. crater; XRU-6 is on the beach directly lagoonward of XRU-5; (and bent) 2' casing, marked with tape only. it is marked it is a bare All of the wells with flag poles attached are easily visible from anywhere in the vicinity; the unflagged ones should be readily identifiable from this letter, plus the attached map/ description. For the purposes of comparison, none of the miscellaneous pipes or casings protruding from the ground have tape or flag markers, and I believe that none of them have slotted casings. No effort need be made tified, wells. to sreserve these other, unidene- While on Runit I was asked if it would be all right if some of the wells were extended or shortened to conform to anticipated changes in ground elevation. This is certainly acceptable; the only request is that every effort be made to avoid knocking local surface soil into the well, either through or beside the casing. I want to thank you and all of the others involved for your cooperation and assistance, If I can be of any further help, please call on me, either directly or through the PASO representative. RWB:ctk Encl. ce: Frank Lybecker, DOE/PASO YW Harry Brown, DOE/PASO Vic Noshkin, LLL Sincerely yours, Robert W. Associate Buddemeter Professor