Auditor (also The Auditor; before 1986 – November 19, 2003[1]) was a feral dog who lived on Montana Resources properties surrounding the Berkeley Pit, an open pit copper mine and Superfund site in Butte, Montana.
Auditor appeared to be a Puli due to his long, corded coat resembling dreadlocks, typical of that breed.
After he began to show signs of arthritis, aspirin was added to his food.
[2][3][4] Holly Peterson, an environmental engineer at Montana Tech, analyzed hair samples taken from Auditor near the end of his life and found elevated levels of "nearly every element imaginable," with a level of arsenic 128 times that normally found in pet dog hair.
Peterson's study was published in the Intermountain Journal of Sciences in June 2006.