The earliest mining technique involved digging shallow pits or trenches, though later inclines were dug to follow coal deposits 100 to 200 feet down. Shaft mining was dominant by the mid-1700s, and heavy timber supports or brickwork were used to reinforce the shafts. Coal was raised out of the mines in large boxes on ropes drawn by mule-driven windlasses and later steam engines. Similar techniques were used to pump out water and keep the mines from flooding. Mules also were used to haul coal inside the mines and were housed there as well.
Reports say the animals appeared healthy due to good care and the stable underground environment.
The mines were in operation 24 hours a day, with workers putting in 12-hour shifts Monday through Saturday and turning out 200 tons of coal a day. Most of the workers were slaves who had been hired out to work the mines, though free blacks also were employed. Mining engineers from England and Wales were hired to improve mine operations and safety, and miners from Britain were attracted to Virginia by the promise of jobs with good wages, favorable conditions and limited hours and the opportunity to buy land and build their own homes. But while working the mines in Chesterfield seemed a golden opportunity to some, it was a risky business. Records of the number of miners killed or injured in accidents are incomplete, but at least 30 men and boys lost their lives in cave-ins and explosions or were asphyxiated by coal dust or poisonous gasses.