KERSEY, Pa. (AP) — The federal Occupational Safety and Health Administration says it's finished its investigation into a deadly landslide at a Pennsylvania landfill.

But OSHA isn't saying what it found yet because it has sent citations to the owners of the Greentree Landfill in Elk County, but the citations haven't been received yet.

The Pennsylvania Department of Environmental Protection is also investigating the Feb. 8 incident when a mound of compressed garbage gave way and collapse onto five workers. Four escaped but 49-year-old William Pierce was buried under 40 feet of trash and found smothered two days later.

The company that owns the landfill, Advanced Disposal, of Ponte Vedra, Florida, says it's making DEP-requested improvements at the landfill and has hired an engineer to assess the accident.