UNDO

UNDO is tackling the greatest challenge of our time: climate change. We are a fast-growing for-profit business that is already one of the biggest carbon removal companies in the world. But this is only the start - we have ambitious plans aligned with great funding, excellent people and an inclusive team.

UNDO has recently been named one of four global winners of the $100M XPRIZE Carbon Removal competition, further giving recognition and credibility to enhanced rock weathering (ERW) as a carbon removal pathway, and UNDO as a scientific world leader in this field.

In addition to our successful ERW operations, we’re now leveraging our expertise and underlying technology to deliver a platform that will enable a global network of project developers to scale ERW to the gigaton level - essential in the fight against climate change.

Homepage: https://www.un-do.com

UNDO is tackling the greatest challenge of our time: climate change. We are a fast-growing for-profit business that is already one of the biggest carbon removal companies in the world. But this is only the start - we have ambitious plans aligned with great funding, excellent people and an inclusive team.

UNDO has recently been named one of four global winners of the $100M XPRIZE Carbon Removal competition, further giving recognition and credibility to enhanced rock weathering (ERW) as a carbon removal pathway, and UNDO as a scientific world leader in this field.

In addition to our successful ERW operations, we’re now leveraging our expertise and underlying technology to deliver a platform that will enable a global network of project developers to scale ERW to the gigaton level - essential in the fight against climate change.

Role overview

Our geochemical modelling framework assists our MRV approach and supports our science team to interpret the data we're collecting. It simulates how silicate and carbonate rocks weather in soils, tracks carbon fluxes, and helps quantify durable CO₂ removal.

As our Geochemical Modeller Lead, you’ll own, lead, and develop this modelling capability – a research-grade system that couples geochemistry, kinetics, and reactive transport with real-world climate and soil data. This role is crucial for turning cutting-edge science into an operational methodology that can be trusted for carbon crediting at scale.

This role can be based in the UK, or Europe.

Where you’ll spend your time

• Lead the development, validation, and deployment of our Python–PHREEQC based geochemical modelling framework
• Drive improvements in how the model represents hydrological, seasonal, and geochemical processes in soils under ERW
• Manage model calibration, verification, and benchmarking against literature, lab, and field datasets
• Oversee technical architecture: modular Python codebase, dynamic PHREEQC script generation, batch simulations, and cloud deployment
• Guide the integration of climate datasets, soil databases, and rock mineralogical inputs into the model pipeline
• Collaborate with geochemists, field scientists, and data engineers to ensure model outputs align with operational measurements and MRV requirements
• Shape the scientific roadmap for modelling at the company – identifying research priorities, new features, and scaling requirements
• Represent the modelling work externally, through peer-reviewed publications, conferences, and collaborations with academic/industry partners
• Provide leadership within the modelling team: setting priorities, mentoring team members, and delivering against objectives and key results.

We’d love to see from you

You combine deep geochemical knowledge with strong computational modelling skills. You’re as comfortable discussing mineral dissolution kinetics as you are debugging code. You enjoy building systems that are scientifically rigorous, computationally efficient, and usable by others. You are collaborative and thrive in multidisciplinary teams that bring together geochemists, scientists, and engineers.

Essential

• PhD or equivalent experience in surficial carbonate geochemistry, environmental chemistry, chemical engineering, earth sciences, or related field
• Demonstrated experience with geochemical or reactive transport modelling (e.g. PHREEQC, PHAST, CrunchFlow, GWB, VS2DRTI)
• Strong grasp of geochemical processes in soils and non-marine carbonate systems including: soil chemistry, kinetic rate laws, unified rate models, chemical speciation, equilibrium, sorption, cation exchange
• Strong analytical and problem solving skills
• Excellent communicator who can confidently explain technical concepts to a non-specialist audience
• Advanced proficiency in Python for scientific computing (pandas, NumPy, visualization).
• Experience designing and maintaining codebases
• Proven ability to validate and calibrate models against experimental or field data
• Ability to set direction, lead projects, and work effectively in a collaborative, cross-functional team.

Desirable

• Proficiency in PHREEQC scripting and PhreeqPy integration
• Familiarity with the determination and estimation of mineral reactive surface area and application to predicting reactivity (e.g., particle size, reactive surface area, surface morphology effects on dissolution kinetics)
• Experience with climate and soil datasets, GIS/geospatial filtering, or API integration
• Track record of scientific publications or equivalent technical reports
• Knowledge of agricultural systems, soil biogeochemistry, or Earth system modelling
• Experience mentoring or leading small scientific/software teams
• Passion for climate tech, sustainability, and science-driven innovation

Working environment

• We have a hybrid working model - we’re remote-friendly but also have an amazing office in County Hall in Waterloo, under the London Eye and overlooking the river. There is no requirement for you to visit this office each week.

What you'll get when you join us

• The opportunity to pioneer carbon removal, impacting the planet for the better
  • Play a pivotal role in building one of the world’s most advanced ERW geochemical modelling frameworks
  • Contribute directly to scaling a billion-tonne CDR pathway and shaping how it is quantified and verified
• Opportunities for publication, conference presentations, and global scientific impact
• A truly committed and collaborative team of passionate field and lab techs, scientists, commercial and operational specialists
• Stock options
• 25 days annual leave (plus bank hols!) and other paid leave such as volunteer, company sick and dependent leave
• Enhanced Family Policies
• Industry leading pension contributions of up to 17%

We're an equal opportunity employer. We are looking for the best candidate based on the value they can add. Our culture is hugely important to us and we welcome applicants of all race, colour, religion, sex, sexual orientation, gender identity, national origin, veteran or disability status. We encourage all candidates who believe they have the required skills and experience for any of our roles to apply. We also welcome applications from candidates who have a keen interest and passion for fighting climate change.

Please visit https://un-do.careers.hibob.com/jobs to apply.