Bury his body in the old sinkhole

This rundown of various “green burial” methods is truly fantastic. The winning method, in my view, involves being turned into a flushable soup:

Alkaline hydrolysis, also known as Resomation (which is a trademarked term) is a process that liquefies rather than burns body tissues. It uses about a sixth of the energy of cremation and has a much smaller carbon footprint, according to Sandy Sullivan, the managing director of Resomation, a company in Scotland that has designed a machine called “the Resomator”. The corpse is placed in a pressurized chamber. The vessel is then filled with water and potassium hydroxide, creating a highly alkaline solution, and heated to 330 degrees. After about three hours, all that’s left are a soft, white calcium phosphate from bone and teeth and a light brown primordial soup of amino acids and peptides. Bodies buried underground decompose in the same way, albeit over many years and aided by microorganisms. Unlike cremation, Resomation doesn’t vaporize the toxic mercury of dental fillings and doesn’t char joint implants, leaving them clean, shiny and potentially recyclable. The bone and tooth material can be ground into a fine ash, as with traditional cremains. The brown liquid, because it’s sterile, can go down the drain.