Surrey Police said Saturday that they have made two further arrests on top of the 16 a day earlier, of whom 12 are facing charges.
The charges range from assault on police to preventing drivers and workers from entering a test-drilling site.
The protesters are campaigning against the extraction of gas by hydraulic fracturing, known as fracking.
They have been gathered for three days in Balcombe, England, where Cuadrilla Resources Ltd. is poised to start test drilling.
Cuadrilla has said it intends to conduct only exploratory drilling in a temporary operation that will not include hydraulic fracturing.