The ore body is a complex, sediment-hosted, sedimentary exhalative deposit consisting primarily of zinc, lead, and iron sulphides.

[1] The deposit lies within the lower part of the Purcell Supergroup and mineralization occurred about 1470 million years ago during the late Precambrian (Mesoproterozoic).

The Sullivan ore body is a complex sedimentary exhalative (SedEx) deposit that consists primarily of zinc, lead, and iron sulphides.

The rocks were deposited on the sea floor in an intracontinental rift basin above a thermal anomaly that drove the circulation of brines.

The ore was then shipped via an extensive 3 ft (914 mm) narrow gauge underground rail system which led to the surface and then on to the Marysville concentrator.

There was also a rail man-carrier that brought men in and out of the mine, descending on a sled full of chairs at a 60 degree bank.

These impressive chambers were belt driven and had well-lit stations where men would monitor and maintain the process and machinery.

"Hot Muck", a rare occurrence of ore with high concentrations of sulfur, would glow red and white and release amazing amounts of heat and gas when exposed to air.

There was a small open pit facility at the top of the mine that was used for the extraction of iron that was shipped to Vancouver.

Conventional mining created huge pillars as miners extracted ore and left massive supports to hold up the ceilings of the drifts.

Two days later, after being reported missing, he was found by Teck Cominco employee Robert Newcombe, who was able to dial 9-1-1 before also succumbing to the oxygen depleted atmosphere.

The two paramedics that responded, Kim Weitzel and Shawn Currier, also died in the oxygen-deprived atmosphere of the shed.