ExCAL were commissioned by O'Rourke Civil Engineering Limited to provide environmental support during the development of a retail park at Hall Street, Blackwood, in Gwent. The development includes an ASDA superstore, six non-food retail units and a fast food restaurant as well as an access road and associated car parking.

Part of the access road and all of the ASDA superstore car park was to be constructed on a closed landfill site which was adjacent to the River Sirhowy. ExCAL carried out monitoring of the river and any leachate breakouts (including on-site chemical testing) in order to ensure that the construction work (in particular dynamic compaction of the landfill) did not cause an adverse effect on the river.

ExCAL are currently monitoring the condition of the site following completion of the construction phase.

Prior to the site development ExCAL carried out a bat survey of the site.