Proposal to undertake ecological assessment of emissions for Local Plan

Tender description

Natural England has raised a question about the potential impacts of the Local Plan upon inland Sites of Special Scientific Interest. AECOM - who have already produced the Local Plan Air Quality Study 2021 propose to undertake detailed dispersion modelling of road traffic emissions of nitrogen oxides (NOx) and ammonia on roads within 200m of the identified SSSIs – Thurstaston Common SSSI, Heswall Dales SSSI and Dibbinsdale SSSI. The methodology will be comparable to the dispersion modelling already undertaken for selected areas in the Local Plan air quality assessment. Ammonia emissions will also be included as their contribution to deposited nitrogen is of increasing concern. Traffic data already provided to AECOM will be used in the dispersion modelling. Four model scenarios will be run. A report will be provided, to be included as an Annex to the Local Plan Air Quality report. It will include both air quality methodology / results, and ecological interpretation.