Meet The Team
Cala Sustain is a consultancy formed of trusted, passionate consultants with proven success in delivering responsible, sustainable business solutions. We have long established, successful working approaches and a wealth of experience across complimentary areas and sectors.
We have a fantastic support team that ensure all of our customer projects run smoothly.
Claire Weaving
Claire is our Office Manager. With over 30 years’ experience supporting businesses of all sizes, she takes care of all our admin, finance and social media needs to keep Cala Sustain running smoothly.
At the heart of Claire’s approach is an understanding of how ambitious business owners are hindered by day-to-day administrative demands. This was the inspiration for setting up her own virtual assistant business and she now helps Mark to spend his time where it’s most valuable.
Tom Wycherley
Tom is an environmental consultant with over 15 years of experience, predominantly within the defence sector. In this time, he has supported the sustainable procurement and through-life of MOD equipment (Air, Land & Maritime) and managed complex environmental protection and sustainability projects.
As a trained Lead Environmental Auditor (IEMA & IRCA), Tom has also incorporated Emissions Reduction, Climate Change Resilience and Design For Environment/ Sustainable Engineering requirements into infrastructure design and procurement projects.
Simon Blackburn
Simon is a seasoned strategy and sustainability consultant with 14 years’ experience delivering market-beating strategies for the world’s biggest brands. His approach combines insight-driven strategic thinking with practical, hands-on implementation and has been applied across multiple sectors.
Simon’s extensive expertise encompasses commercial growth strategies, sustainability, revenue management, pricing, and finance. The scope of his experience makes him exceptionally qualified to advise clients wishing to adopt a ‘triple bottom line’ approach to sustainable business growth.
Si Parker
Si is an experienced Systems Lead and Senior Data Engineer. He has applied his data quality assurance expertise across autonomous flight (drones), solar renewables, broadcast TV, genetics, healthcare, GIS (Geographic Information systems), intellectual property, and finance.
As well as being a hands-on software developer, Si is a skilled systems, data and network architect. After adopting Python for a project in 2009, Si has watched it grow into the dominant language in data. As well as writing ETLs to shape and manipulate datasets, Si has used Python in Devops, ML/AI and extensively in modelling.
Paul Stevenson
Paul is an Energy & Environmental (E&E) consultant with over 40 years’ experience. With impressive credentials – from Fellow of the Energy Institute (FEI) and Chartered Engineer (C.Eng) to ESOS lead assessor and accredited GHG assessor – Paul has unrivalled expertise in environmental standards.
Paul has been active in several UK Government climate change and environmental programmes, and has worked with governments and donor organisations across the globe.
Lisa Owen Dobie
With over 20 years’ experience, predominantly in the defence world, Lisa is a highly experienced environmental consultant. She has supported MOD equipment across all domains: from land vehicles and submarines to nuclear decommissioning and waste disposal.
Lisa’s broad technical knowledge and solution-focus has delivered projects covering environmental management, sustainability, climate resilience and reduction, energy management, environmental protection and supporting MOD Delivery Teams. This includes assisting with the production of Defence Standards 00-051 Environmental Management Requirements in Defence.
Caroline Gowing
Caroline is a people-focused change expert working across defence, wider business and the charity sector. With an academic background in psychology and environmental strategy, she specialises in helping organisations and senior leaders to define, embed and deliver complex change.
In order to deliver sustainable transformation, a big part of Caroline’s work is understanding how people will respond to change. She places particular emphasis on values and behaviour: how to really understand the culture of an organisation, how to nurture it, and how to alter it when your vision changes.
Mark Hedges
Mark is Cala Sustain’s Managing Director. Leading projects across the organisation, he draws on over 25 years’ experience of enabling sustainable business. This includes time as the Head of Sustainability at a multinational engineering and as a Technical Committee Member at the British Standards Institute, where Mark helped draft the world’s first standard in sustainable procurement.
As well as an honours degree in environmental science, a post grad in business management and being a lead auditor, Mark is a Chartered Environmentalist (CEnv) and Member of the Institute of Environmental Management and Assessment (MIEMA).
Mark Thurstain
Mark is an experienced commercial data scientist. Over the last 25 years, he has creatively analysed data to help organisations and governments make informed decisions. This includes over 20 years running his own spatial data analysis company, Geofutures, working with the Ministry of Housing, Communities & Local Govt, Office for National Statistics, Grosvenor Estates and The Audit Commission.
After leaving consumer champion Which? as Head of Data in 2018, Mark has consulted on a wide range of projects. Most recently he has supported DE&S, the British MOD’s defence procurement arm, to develop a data infrastructure to track equipment life-cycle carbon.
Shelley van der Pas
Shelley ensures that all aspects of Cala Sustain are managed successfully beyond our technical services. With a background in social sciences and finance, she provides business management that ensures team cohesion and efficient processes.
By ensuring the wider business is running smoothly, Shelley frees up the rest of the team to focus on technical delivery for our clients and helps to maintain a great team spirit and positive culture.