I know it's not quite the same circumstances but when I got a lot of my girlfriends blood soaking through the mattress I rolled her up in it and tied it all together with string. That night I drove her to Epping forest and left her under as much loose leaf material as I could. After I made the tearful appeal for her return on the TV for the police, I went back to burn the mattress and re-bury the body.

Hope this helps.