FoE Canada's Carbon Tax Proposal

Friends of the Earth Canada released a carbon tax proposal for Canadian Large Final Emitters on Thursday Jan 25 - an opinion piece they released detailing the proposal ran in the Montreal Gazette on Jan 27.
An interesting point about the proposal - taxes paid by each emitter would go into their own individual trust account. they would then have the chance to spend that money on emissions-reducing initiatives at their own facility, but only have a few years to spend it before losing it.
Link
My comment -
This seems innovative to me and potentially useful - although any comments on drawbacks I've missed would be appreciated. The biggest challenge I see would be the criteria for emissions-reduction initiatives. You would want it criteria-based to encourage innovation, you would need to have strict standards for any offset credits like soil management or forestry initiatives, and you would want to keep the costs of approving and monitoring all of these initiatives minimal. But if I were a company, I think I'd prefer a 'tax' I could then spend on myself to one the government keeps...