Campaign Summary

Campaign Objectives

4C's first catalytic grant campaign was anchored in a set of three goals, which have created a template for subsequent campaigns:

1. Enable first-of-a-kind projects

Support groundbreaking demonstrations that embed carbon removal directly into concrete production—accelerating innovation, proving viability, and paving the way for broader deployment.

2. Showcase diverse approaches

Fund a wide range of technologies and strategies—from bio-based additives to mineralization methods—that highlight how carbon removal can be embedded across the concrete value chain.

3. Prioritize replicable projects for the region

Select solutions designed for repeatability in the Four Corners states, emphasizing local materials, climate conditions, and community benefit—so today’s pilot can become tomorrow’s standard.

1. Coalition Formation & Campaign Planning

The four founding members of the 4 Corners Carbon Coalition aligned on concrete as the focus of their first campaign—an ideal starting point for regional impact.

As one of the most widely used materials on Earth, concrete is both universal and hyper-local, produced within the borders of every participating jurisdiction. The Western U.S. is also experiencing rapid growth in construction and real estate, meaning large volumes of concrete will be poured in the years ahead. This made it a strategic and timely platform for advancing carbon removal innovation where it’s most needed.

2. Campaign Launch & Request for Proposals

In late 2022, the campaign launched publicly with a call for proposals focused on innovative ways to combine concrete and carbon removal. The campaign was shaped by extensive community engagement and local input gathered by Boulder County, Flagstaff, Salt Lake City, and Santa Fe. To ensure scientific rigor, Carbon Direct—a leading carbon management firm—partnered with 4CCC to help design the application criteria and evaluation framework.

3. Technical Review & Award Selection

During early 2023, submitted proposals were reviewed through a two-tiered process. Carbon Direct convened a panel of subject matter experts to evaluate technical merit, carbon impact, innovation potential, and community benefits.

Local government representatives from the four partner cities then reviewed finalist projects, integrating community priorities with expert guidance. Four standout projects were selected for funding—each demonstrating a novel approach to carbon removal in concrete.

4. Project Implementation & Monitoring

In spring 2023, the four funded projects officially launched. Each team began implementation and reporting under a shared monitoring framework co-developed by 4CCC and Carbon Direct to track progress, carbon impact, and local co-benefits.

Boulder County coordinated project oversight and funding agreements, while 4CCC continues to support grantees with technical assistance and plans for follow-on funding to help scale successful models across the region.

Awardees

Four awards were selected through the 4 Corners Carbon Coalition Fund, all supporting local startups and organizations based in the Four Corners states and completing projects in the region. These projects represent a range of approaches—including R&D, proof-of-concept demonstrations, pilot systems, and commercial retrofits—focused on removing and storing CO₂ in concrete.

The Boulder Block

Boulder, Colorado

Award: $20,000

Travertine Technologies, a woman-led startup based in Boulder, Colorado, completed a project with support from the 4 Corners Carbon Coalition to explore how carbon-negative calcium carbonate—made by pulling CO₂ from the air—can be used to make lower-emission cement.

The project tested small cement cubes that substituted up to 15% of traditional Portland cement with Travertine’s carbon-sequestering material, helping lay the groundwork for more climate-friendly construction materials.

Air-to-Concrete

Flagstaff, Arizona

Award: $100,000

CarbonBuilt, an XPRIZE-winning company based in California, partnered with Flagstaff’s family-owned Block-Lite to create one of the country’s first ultra-low carbon concrete production sites.

With support from the 4 Corners Carbon Coalition, the project is retrofitting Block-Lite’s facility to use captured CO₂ from the air—rather than steam—for curing concrete, permanently storing carbon while cutting emissions by up to 100%.

Regenerative Quarry

Boulder, Colorado

Award: $100,000

Minus Materials, a Boulder-based, woman- and LGBTQ+-led startup, launched a first-of-its-kind “regenerative quarry” pilot with support from the 4 Corners Carbon Coalition. The project used microalgae to grow carbon-negative limestone by capturing CO₂ directly from the air and turning it into a solid mineral form.

This algae-grown limestone was then used as a climate-friendly filler in a concrete slab, demonstrating a novel pathway to cut emissions from cement without changing how it’s made. The project offered a bold new approach to sustainable building materials—one that could someday help replace conventional quarrying altogether.

Hemp + Biochar Construction

Durango, Arizona

Award: $119,000

The Hemp CO₂llective, a grassroots initiative based in Colorado, carried out a demonstration project with support from the 4 Corners Carbon Coalition to explore the potential of industrial hemp as a tool for carbon removal. The team cultivated hemp at the CSU ARDEC South research farm and produced biochar from the harvested biomass, capturing and storing carbon in a stable form.

This project offered a hands-on proof of concept for how climate-smart agriculture and carbon-smart materials like biochar can work together to remove carbon from the atmosphere while supporting local farmers and regenerative practices.

FAQ

What does concrete have to do with Carbon Removal?

Concrete is one of the most widely used materials in the world—and one of the hardest to decarbonize. Its main ingredient, Portland cement, is responsible for about 8% of global CO₂ emissions. But concrete also offers major potential for carbon removal through methods like CO₂ curing, carbon-storing aggregates, and mineral additives.

Since concrete is produced locally and used everywhere—including across our fast-growing Western communities—it’s an ideal platform for demonstrating climate innovation.

What criteria was used to select awardees?

Projects were selected through an open Request for Proposals (RFP) process and evaluated by a panel of independent technical experts convened by our partner, Carbon Direct.

‍The evaluation focused on five key areas: carbon removal potential, quality and durability of removal, innovation and scalability, community and ecosystem co-benefits, and team qualifications. Final award decisions were made collaboratively by representatives from the four partner jurisdictions.

What was the level of funding awarded to the different projects

In its inaugural round, the 4 Corners Carbon Coalition awarded a total of $389,000 in catalytic grants, provided collectively by the four member governments. Individual project awards ranged in size depending on scope, need, and readiness, with individual grants ranging between $20,000 and $125,000.

These early-stage investments were designed to help first-of-a-kind projects demonstrate their potential for carbon removal, community benefit, and regional replicability.

What were the biggest lessons learned from the campaign?

By focusing on a shared challenge like carbon-intensive concrete, the coalition demonstrated how place-based funding can support highly diverse, technically ambitious projects grounded in regional context.

Partnering with Carbon Direct helped ensure scientific rigor, and coordinating across jurisdictions gave projects the visibility and credibility needed to attract follow-on support. The campaign also highlighted the value of flexible, catalytic funding to de-risk early-stage ideas and the importance of building monitoring and reporting frameworks that balance rigor with accessibility.

Carbon Removal+ Concrete