The Environment Agency has served an enforcement notice on Waste4Fuel to stop any further waste being brought into the site.
The means any person depositing waste at Waste4Fuel in St Paul's Cray will be committing an offence and may face action from the Environment Agency.
Several conditions need to be met before further waste can be accepted at the site.
The Environment Agency is waiting for a written decision from the High Court after it dismissed a contempt of court case last week for failure to maintain fire breaks and store new waste separately at the site.
The High Court order required all combustible waste to be cleared from the site by May 1 this year, and the Environment Agency will consider what action it should take once the reasons for the courts' decision has been considered.
Andrew Pearce, Environment Agency area manager for Kent and south London, said: "This enforcement notice is another step towards the Environment Agency bringing the Waste4Fuel site back into compliance.
"The High Court Order we secured last year has not been complied with, and waste on site is slowly increasing.
"We understand the frustration of local residents and are doing everything within our power to bring the site back into compliance as soon as possible."