Dear Sir,
I am Iulian Seba, an exploration geologist with a large experience, included field works in Congo RC and Mali,
Also, desks studies (compiling old data, Remote Sensing, GIS, planning exploration works etc) for countries like Nigeria, Cameroon, Togo.
Perhaps you have some documentation in Russian; if the quality it is good, a text can be scaned, placed in an OCR software then translated.
With maps, blue prints, etc, it is more easy