A limestone quarry in County Durham supplies high quality aggregate to the building sector. The minerals company identified a continuing demand for this material, and this resulted in a proposal to extend the quarry to the east to increase the amount of mineral that could be extracted. The existing rate of aggregate production was in the order of 300,000 tonnes per annum, giving the quarry a life expectancy of approximately 5 years. The proposed quarry extension would extend the operational area of the site by 50%.
BSG was commissioned to undertake an ecological impact assessment of the proposed quarry extension site. This involved an appraisal of the site, stakeholder consultation, scoping of all necessary ecological survey work, completion of those surveys (using appropriate methods and at an appropriate time of the year), evaluation of potential impacts and the development of a robust and realistic mitigation and compensation strategy. We worked closely with the appointed landscape architects to ensure that the final restoration scheme included measures that would adequately compensate for the loss of biodiversity interest within the site, as well as providing some ecological enhancement.
Whilst the baseline ecology surveys found that the proposed extension site was of low botanical importance and with no protected species present, we discovered that the settlement lagoons within the adjacent operational site supported a large population of great crested newts. Our assessment concluded that the newt population was of regional importance, and therefore needed very careful consideration if the proposed development was to proceed without significantly affecting this European protected species.
Working with the appointed hydrological consultants, it became clear that the lagoons supporting the newts were being artificially supported by water pumped from the quarry void. Consequently, without compensation, when the quarry eventually ceases operating the lagoons will dry up, putting the newt population at risk. We worked with the project team to devise a restoration scheme that would provide a series of groundwater-fed ponds within the base of the quarry. These ponds would ensure the long-term viability of the great crested newt population by providing enhanced habitats for them.
The outcome of the ecological impact assessment process, which was summarised in the Environmental Statement, was that all identified ecological impacts were addressed through mitigation and compensation. This contributed to the submission of a successful planning application, and planning permission was granted.