The Environment Agency has objected to controversial plans for up to 80 homes on green belt land in Flackwell Heath, warning that the development could pose an “unacceptable risk” to groundwater.

Berkeley Strategic Land Ltd has submitted an outline application seeking permission to demolish existing buildings and construct up to 80 homes on land north of Heath End Road.

Plans include 50 per cent affordable housing, a new primary access onto Heath End Road, and an emergency and agricultural access via Spring Lane.

The 13-acre site, currently known as Heath End Farm, comprises agricultural land, equestrian use, a farmhouse and a number of barns.

Although the land is designated as part of the Buckinghamshire Green Belt, Berkeley argues in its application that it should be considered “grey belt” and therefore suitable for development.

However, the Environment Agency has recommended that planning permission be refused unless further information is provided addressing the potential risks to groundwater.

Its objection states: “The applicant has not supplied adequate information to demonstrate that the risks posed to groundwater can be satisfactorily managed.”

It also raised concerns about the proposed use of deep borehole soakaways, dewatering, infiltration and piling through part of the site identified as a historic landfill.

The Environment Agency said it would maintain its objection until it received a satisfactory hydrogeological and piling risk assessment demonstrating that the risks could be managed.

The Chiltern Society has also objected, arguing that the development would erode the green belt, worsen congestion and result in the permanent loss of agricultural land.

In an objection submitted on behalf of the society, Richard Lewis claimed the site contributed strongly to three purposes of the green belt: preventing urban sprawl, stopping neighbouring settlements from merging and protecting the countryside from encroachment.

He argued that the scheme would extend Flackwell Heath towards development around Abbey Barn Lane and the outskirts of High Wycombe.

Mr Lewis also raised concerns about congestion on Heath End Road and Spring Lane, claiming the road network had reached capacity.

He said: “Traffic from both of these housing sites would feed into Spring Lane. This will create impossible gridlock on the steep hill part of Spring Lane as multiple vehicles try to pass each other on this single track road with limited space in the passing places.”

The objection also argues that the scheme would increase pressure on medical services and that homes close to the M40 could be affected by traffic noise.