Sucking up CO2

Founded: 2021

HQ: Vancouver, BC

Carbon-negative mining

Big Picture

Metals are key to a low-carbon future, but it can take 100-200 tons of rock mined to extract one ton of ore. Churning out megatons of waste each year decimates local ecosystems and pumps out as much CO2. Some of this waste, or “mine tailings,” naturally undergoes a chemical reaction that traps CO2 from the air as solid rock. If sped up, tailings could be one of Earth’s largest permanent carbon sinks hiding in plain sight.

How it Works

Arca’s suite of technologies speeds up the reactivity of mine tailings for permanent carbon removal. Proprietary tailing activation reactors use bursts of energy to accelerate the natural chemical process by 10-50x. Autonomous rovers also churn tailing surfaces, exposing the activated tailings to more air to convert atmospheric CO2 directly into metal carbonates, stably storing the carbon away for millennia. 

Unfair Advantage

Arca enables mining operations to “inset” with CDR, turning liabilities into revenue-generating assets. This unlocks access to hundreds of mines in production and legacy and buried tailings, together representing 40 GTs of potential CO2 storage. With Arca’s accelerated mineralization technology and robust verification systems, tailings present a swift path to gigaton-scale carbon removal.


Gigatons of CO2

storage potential in mine tailings


Paul is a serial entrepreneur with three exits. Prior to Arca, Paul built a solar leasing company in India. He holds an MPhil in Economics from Cambridge.


Greg is a global leader in carbon removal with mine tailings. He is a Professor of Geological Sciences at the University of British Columbia.

A pathway to carbon-negative mining

Canadian Mining Journal

Mining is a polluting business. Can new tech make it cleaner?

National Geographic

Cleantech startup aims to transform mine waste into a ‘climate solution’