The sheriff's study comes as four former cemetery workers await trial for allegedly digging up graves and reselling the plots.
Sheriff Dart says records show that well over 140,000 people are buried at Burr Oak. Dart says that is a very conservative number because it does include the records that were destroyed or not kept.
While burials continue at Burr Oak, Dart is urging people to think twice about burying loved ones there.
Robert Andrews' mother died unexpectedly in December. Several members of the Andrews family are buried at Burr Oak Cemetery. The plan was to have Lizzie Kate Andrews buried in a family plot previously purchased by the Andrews. The family finalized those arrangements and additional costs with Burr Oak.
"We paid the money, and after we left the office, we actually drove out to the gravesite location where my brother is, and his headstone was fine...everything was fine," said Robert Andrews.
Everything was fine until Andrews received a phone call from a Burr Oak administrator just a couple hours before his mother's funeral was set to begin.
"He said that they could not bury my mother...choose another location," said Andrews said.
Andrews was told there were remains already in his mother's paid-for-plot. This does not come as a surprise to Cook County Sheriff Tom Dart.
"Every third or fourth burial, they're finding in a plot where no one is supposed to be, there's someone there," said Dart.
After studying Burr Oak's poorly kept records, Dart concludes in a new report that there is not enough room to bury anymore people there. Dart says stacking caskets or discarding remains may have been more widespread because his study shows that there may be thousands more people buried than there is space.
"With a very, very conservative estimate, there is room for about 138,000 people there," Dart said.
Dart says Burr Oak records show well over 140,000 are buried in the Alsip cemetery.
Yet burials continue.
Leak and Sons Funeral Home says many of their customers still insist on Burr Oak and they can't stop them.
"We as a funeral home directors are not supposed to give advice on certain cemeteries," said Spencer Leak Jr., funeral director.
Burr Oak did not comment. The cemetery is in bankruptcy. So, by judge's orders, it must continue to operate.
Meantime, a week after Lizzie Kate Andrews' funeral, Burr Oak moved her and another family member's remains to a different section of the cemetery.