B.A. Hydro Solutions Limited were appointed by G.M. Bailey on behalf of Cheam School in 2010 to investigate the potential to develop a new open loop ground source heating system for a new building at the school.

A Hydrogeological Assessment (HGA) established that an open loop system was feasible. The School chose to proceed and permissions were secured to drill one abstraction and one injection borehole at the school.  Drilling was arranged and managed by B.A. Hydro Solutions Ltd and completed in the summer of 2011.

The geology reported in the HGA was confirmed as correct and the yield and infiltration capacity slightly exceeded expectations.  The system was licensed and commissioned in Autumn 2011.

Cheam School is a private prep-school originally founded in 1645, making it the oldest private school in the United Kingdom. The establishment has in recent times schooled Prince Philip, The Duke of Edinburgh and Charles, Prince of Wales.  The School has been on the present site since 1934 and had a steady building programme.

In 2010 many years of planning and fund raising culminated in the preparation to build one of the most recent buildings on site, the Duke of Edinburgh Building.  B.A. Hydro Solutions Limited were engaged to build up a design for a ground source heating system for the new buildings.  B.A. Hydro Solutions Ltd developed an open loop ground source heating system design and were subsequently successful in winning the contract to drill the abstraction boreholes, supply, install and commission the pumping and injection system, and to secure all necessary regulatory permissions.

The hydrogeological setting beneath the school is slightly challenging due to the dip of the strata and folding in this region being poorly documented and there being few investigations.   B.A. Hydro Solutions Ltd spent time drawing together all available information in order to produce a detailed Hydrogeological Assessment which set out a conceptual understanding of the hydrogeological setting.  This indicated that the Chalk was present at a depth of around 85 metres and should be able to sustain a sufficient abstraction to maintain a 60 kW heat pump.

A drilling and pumping system specification was generated by B.A. Hydro Solutions Ltd; competent contractors were shortlisted and invited to tender, a contract was awarded and drilling began in summer 2011.  The geological sequence, strata thickness and depths were proven to be almost exactly as predicted by B.A. Hydro Solutions Ltd.  The yield from the two holes was found to be slightly higher than calculated.  The abstraction and injection boreholes were chosen based on interaction and performance deduced from test pumping.

The abstraction borehole was equipped with a submersible pump and the injection borehole with a discharge line.  The holes were formally test pumped, data analysed and submitted to the Environment Agency (EA) to support the formal license application.  A license to abstract, and permit to discharge were issued in the autumn of 2011 by the EA allowing the system to be commissioned on time and on budget.