WROTHAM QUARRY – 2014 – Pope Plant Limited

Upper Erosion bench works, Stream diversion, Mineral exposure & Restoration

Early 2014, Pope Plant Ltd was asked to view the upper north bench in the North quarry at Wrotham.

Over the course of a record breaking wet winter large surface water erosion gulley’s had formed, jeopardising the integrity of the above restoration and engineered stream.

We were asked to advise by GWP consultants whether there was a safe working method to carry out the necessary repair works. Stability issues were raised and plant size agreed before detailed RAMS were submitted by Craig Pope and viewed by the Hanson H&S team.

The works comprised of

re-shaping the upper bench to camber towards restored area rather than allowing water to shed off the quarry face. The excess sand was utilised to progressively fill in the erosion gulley’s.
Small bunds were constructed at regular intervals, the whole area was covered with 200mm of top soil.
The purpose was to allow the excess water to soak downwards into the upper sand face rather than cascade over quarry face.

The works were carried out with regular daily monitoring by Pope Plant supervisor and the there were zero H&S issues to report. The erosion has not re-appeared some 12 months later, the works were deemed successful.

Due to the bad weather, it was found that tree’s had come down along the stream banks within the South Quarry.

This had allowed the stream to cut a new route through the bank and into the South Quarry. The whole quarry floor was now submerged under approximately 8 metres of water. Pope plant were utilised to clear vegetation, level surrounding area and construct a lined stream diversion to link the water course back to the original destination. The water within the quarry was allowed to drain down into the water table over the summer months with excess water pumped back into the local sewage system. There are still on- going intermittent works and the temporary diversion still in place awaiting the specification to repair old stream bed.