Probably a TDS meeting; individuals identified on picture back and accompanying labeled image, including Moeller, Lamp(?), Laise, Allen, Noon, Biersach (Sr and Jr), Ohlinger, Kumler, Mooers(?), Gilliard, Lewis, Matson, W Balderston(?), Disckson
Photo caption lists Morrison Rutherford DS35, Randolph Newman DS35, Robert Morris DS36, Y.T. (probably Yours Truly), Mersman[?] unknown, Richard Hewitt DS35, Kelly unknown, dog Annie. From the skyline, this looks like someplace up Birch Creek, Cedar…
Jack Aoki DS32. Also a file containing a memoir or life story from his wife Barbara, with a cover letter from his daughter Sarah Eppenbach, and a second picture of Aoki on horseback, prior to Deep Springs and part of his Deep Springs application