Ci Davis, activist for Extinction Rebellion Sheffield and REACH (Rebuilding Environment And Community in Hoyland), says the coal should remain in the ground, and not be burnt.
Mr Davies says Barnsley Council should explain why coal is being transported from the borough, when the authority declared a climate emergency in September 2019.
He added: “We are asking Barnsley Council to tell us what was known about the coal seam at the planning stage and what information has been provided to the public.
“We also call upon them to explain allowing coal to be transferred from the Borough given they have declared a climate emergency.
“We also call upon the constructors, the developers and the client to stop the transfer of coal, until such time that the community can be assured that the coal will not be converted to coke or burnt.”
Campaign groups say that on February 5, 44 ton lorries were seen entering the Hermes construction site to collect coal, which was being extracted from the ground.
The new Hermes “Colossus” hub – the largest of its kind in Europe – was met with strong opposition before it was rubber-stamped by Barnsley Council last October.
Resident Mark Goodison, whose petition against the plans reached almost 2,000 signatures, said that the area is not suitable for such a large development, and has concerns about infrastructure, wildlife and safety.
However, the council said that the warehouse would provide up to 2,000 jobs, and that a six-week consultation period was held for residents to have their say.
Councillor Tim Cheetham, cabinet spokesperson for regeneration and culture, said: “Across Barnsley, it is common to come across small and shallow coal seams during the earthworks phase of construction projects. Where this is the case, such coal workings have to be removed to avoid land stability issues.
“Given that quantities are usually modest, local planning authorities are not involved in the incidental coal agreement process, but in this case, we can confirm the coal being removed is to be mixed with other materials and used within the cement and concrete industry.”