The best place to store a gigaton of carbon might be right where you left a gigaton of waste. That is the simple, almost cheeky premise of Arca, a Vancouver startup that doesn't build carbon removal facilities so much as it hijacks them. The company takes the alkaline mine tailings and industrial waste piles that mining companies spend millions to manage and, using a bit of chemistry and a lot of process engineering, turns them into a permanent sink for atmospheric CO₂. It is a business model built on a geological handshake: miners get a new revenue line and a cleaner legacy, while the world gets durable carbon storage without a fresh footprint.
A process validated by rock, not slides
Arca’s core science is not new. The natural carbon mineralization of certain alkaline rocks,like the waste from nickel, diamond, or platinum mines,is a well-studied process. CO₂ from the air reacts with magnesium or calcium in the rock to form stable carbonate minerals, essentially locking the carbon away as stone. The problem has always been speed; nature works on a geological timescale, not a climate deadline. Arca’s proprietary intervention, developed over two decades of research by co-founder and chief scientist Dr. Greg Dipple at the University of British Columbia, accelerates that reaction. The company is sparse on the exact levers it pulls, citing trade secrets, but the output is validated: its process is ISO-certified for carbon removal and, according to the XPRIZE Foundation, is already deployed and removing CO₂ today [XPRIZE Foundation, c. 2023-2024]. The unit of output is not a software license or a sensor reading, but a verified tonne of carbon permanently converted to rock.
The team: from pay-as-you-go solar to petrology
The founding trio brings together the necessary, and often divergent, worlds of deep science, scaled operations, and storytelling. Dr. Greg Dipple provides the foundational petrology and academic credibility. CEO Paul Needham, who previously co-founded and sold Simpa Networks, a pay-as-you-go solar company in India, to ENGIE, knows how to build and finance distributed infrastructure in partnership with large, incumbent industries [Perplexity Sonar Pro Brief, retrieved 2024]. COO Lydia Firth rounds out the operational core. Needham’s earlier career as a journalist, including a stint at CBS News, might seem an odd fit, but in a market where corporate carbon buyers need a compelling narrative of permanence and impact, it is arguably as relevant as an engineering degree. The team’s composition signals a company built to be a commercial intermediary, not just a research project.
Traction through partnership, not possession
Arca’s commercial strategy is its most distinct feature. Instead of raising billions to acquire land, permit mines, and move rock itself,the model of some direct air capture rivals,Arca partners with existing mining companies. It provides the technology and expertise to transform a liability (tailings management) into an asset (carbon removal credits). This capital-light, asset-partner approach is already bearing fruit. The company is working with Talon Metals, which is in a joint venture with Rio Tinto, on a nickel project aimed at the U.S. battery supply chain [cpecn.com, retrieved 2026]. More significantly, Arca has secured a landmark offtake agreement with Microsoft to deliver nearly 300,000 tonnes of durable carbon removal over the next decade [cantechletter.com, retrieved 2026]. For a seed-stage company, a deal of that scale with a buyer of Microsoft’s caliber is a powerful traction signal, effectively de-risking a significant portion of its future revenue.
| Founder | Role | Key Background |
|---|---|---|
| Dr. Greg Dipple | Co-founder, Chief Scientist | Professor of Geology, UBC; 20+ years researching carbon mineralization in mine tailings. |
| Paul Needham | Co-founder, CEO | Former CEO/Co-founder of Simpa Networks (acquired by ENGIE); ex-CBS News producer. |
| Lydia Firth | Co-founder, COO | Operational lead; background in scaling climate tech ventures. |
Where the wheels could come off
For all its elegant symmetry, Arca’s model faces real and specific pressures. The business is inextricably linked to the mining industry, which brings its own set of challenges.
- Commodity exposure. Arca’s potential host sites are active mines. If nickel prices crash, a mine may curtail operations or close, taking a planned carbon removal project with it. The company’s fate is partially tied to commodity cycles outside its control.
- Logistical complexity. Every mine site is unique. Tailings chemistry, physical layout, water access, and local climate all vary. Deploying a standardized, cost-effective process across a portfolio of global sites is an engineering and project management challenge that looks simple only on a diagram.
- The permanence debate. While mineral carbonation is considered one of the most permanent forms of storage, the carbon accounting and verification around enhanced mineralization in active waste streams is still evolving. Arca’s ISO validation is a strong start, but the company must continually prove additionality,that the carbon stored would not have been mineralized naturally at the same rate,to maintain credit integrity and price.
The company’s answer to these risks is its partnership model itself. By integrating into the mine’s own waste management flow, it becomes a service provider helping the operator meet its own environmental goals and generate revenue, aligning incentives for long-term collaboration. The Microsoft offtake also provides a stable demand anchor to help finance these site-specific deployments.
The next twelve months
Arca is reportedly preparing a Series A fundraise [Axios Pro, Oct 2025]. The proceeds will likely fuel the deployment work for its Microsoft commitment and the pursuit of similar offtakes with other corporate buyers. The key metric to watch will not be tonnes removed,though that matters,but the number of signed partnership agreements with mining majors. Each new partner represents a scalable pipeline of future removal capacity, as every mine produces tailings daily for decades. The company’s ability to move from bespoke pilot projects to repeatable, bankable deployment packages will define its transition from a promising science project to a industrial climate platform.
Back of the envelope, if Arca’s process costs evolve to, say, $150 per tonne, the Microsoft deal represents a $45 million revenue stream over ten years. The real prize is proving that model at one site so it can be replicated across dozens. To reach gigaton scale, Arca must out-compete not just other carbon removal startups, but the incumbent cost of doing nothing: the mining industry’s traditional approach to waste management. Its success hinges on making carbon storage a cheaper, more profitable alternative to simply piling rock and hoping for the best.
Sources
- [arcaclimate.com, retrieved 2024] Arca - An Industrial Mineralization Company | https://arcaclimate.com/
- [XPRIZE Foundation, c. 2023-2024] Arca (Carbon Removal Team profile) | https://www.xprize.org/people/arca
- [Perplexity Sonar Pro Brief, retrieved 2024] Arca company brief | (Source snippet)
- [cpecn.com, retrieved 2026] Arca working with Talon Metals | https://cpecn.com/
- [cantechletter.com, retrieved 2026] Arca secures Microsoft offtake | https://cantechletter.com/
- [Axios Pro, Oct 2025] Mining carbon removal startup Arca readies Series A raise | https://www.axios.com/pro/climate-deals/2025/10/29/arca-series-a-microsoft