How do I delete columns that workflows create in a list

I was doing some experimenting with some workflows for a task list.

Now when I go a view the list, I see a couple of work flow columns from workflows I deleted?

I know how to un-check them so I don't see them in the view. But how do I delete them from the list, they don't show up in the column list, but they show up on the modify view settings? Or am I stuck with those from now on?

All your help is appreciated!

See Below edit view list:

Will