The Geokinetics in situ shale oil project is a cooperative venture between Geokinetics and the US Department of Energy. The objective is to develop a true in situ process for recovering shale oil using a fire front moving in a horizontal direction. The project is being conducted at a field site, Kamp Kerogen, located 70 miles south of Vernal, Utah. This fifth annual report covers work completed during the calendar year 1981. During 1981, one full sized retort (Retort No. 26) was blasted and the following three retorts were processed: (1) Retort No. 24 operations were continued until July 23; (2) Retort No. 23 was ignited and processed during the calendar year; (3) Retort No. 25 was ignited and burned for 77 days during 1981.