From the emission trading system of EU https://ec.europa.eu/clima/policies/ets_en: the price of 1 ton of CO2 has reached 50 EURO. Not sure if similar system has been  adopted here is the US, but would Thacker Pass consume CO2 within the process, than it could create another interesting revenue stream with very high margin, assuming of course that those indian bones will not kill the project prior that.