Cash deposit by a senior citizen

Hi all, 

My grandfather is aged 85 years now and was into agriculture for almost 60+ years in his life. He has never filed ITR as all his income is agruicultural income from rural areas, and always below taxable limits. Now he has a savings of 10 lacs(cash) with him which he wants to deposit in SB a/c. Will there be any tax impliations on this deposit?

Note: He has no property or any other asset registered on his name. Earlier he had few rural agricultural lands which he had sold few years back which is also the major source of his savings. Waiting for reply...