Method under scrutiny is the so-called cyclic steam stimulation, which is the same it was being used at CNRL's Primrose site during a major spill last year.
The massive copper project, owned by Wanbao Mining Ltd, drew international attention in 2012 when police brutally dispersed protesters, injuring more than 100 Buddhist monks.
Steinmetz and three BSGR directors argued that Global Witness had obtained personal information about them without authorization and wanted it to be forced to reveal what specific data it held.
The touted expansion of the world's largest underground copper mine is two to three years behind schedule and will require $2 billion more than initially planned, said the company.
According to the legislators, international mining companies —mainly from Australia, Canada and the U.K— are using the forced labour of Eritreans in their operations.
