He requested that his ashes be spread on Taylor Mountain Forest, because he had “so many good times and happy memories there” (paraphrased, but fairly accurate is memory serves)

Many of his victims remains were found in that area, so you can imagine what his happy memories were.

It’s difficult to know what exactly happened to his ashes, I can’t imagine the Police or victims families being happy if they were spread in the same area he committed many of his crimes, but a google search shows sources differ on whether the request was granted.

I am sure I read somewhere that his ashes remain in the prison he was executed in, buried somewhere that lifers get buried.