Decision details

A hole appeared in mid-October in an area of public open space adjacent to No. 30 Highbarns and arrangements made for geotechnical engineers to visit the site.
The collapse has revealed a brick shaft approximately 1.2m in diameter that appears to be a former well.
Land close to this area has had stabilisation works carried out to it over the past decade.
Intrusive ground investigation work was carried out around the collapse feature to ascertain the extent of the sub-surface and loosened ground to enable the design of remedial works.
Initial results of the dynamic probing has identified a void running from the edge of the collapsed feature towards No. 30 East Green, and the rough scope of this void has been identified as being approximately 13.5 m x 4 m.
Cabinet have agreed to the use of the Dacorum Development Reserve to fund the remediation works.
Cabinet have delegated authority to award a contract for the remediation work to the Assistant Director Corporate.

To award a contract to BAM Ritchies to carry out the remediation work.
The remediation contract costs are £295,000, and are based upon the estimated volume of material to fill the void. The volume of material will be remeasured and costed once the compaction grout is mechanically pumped in to the void.
Consultation on the award of this contract has taken place between the Leader of the Council and the Corporate Director of Finance

There does not appear to be any other options other than remediation.
Fencing off the site has been a temporary solution to ensure no one falls in the void but this does not prevent the wider issue of a further collapse if the void is not filled.