West Penwith Moors and Downs Site of Special Scientific Interest (SSSI) was notified in 2022 and covers an area of approximately 3,044 ha. Within the SSSI are eleven valley fen (mire) features, fed largely, but not exclusively, by groundwater from the shallow granite aquifer.
This project aims to develop a groundwater monitoring strategy to assess the spatial and temporal variations in groundwater quality across the valley fen features.
A desk study focused on the identification of existing potential groundwater monitoring points such as springs, wells and boreholes using Ordnance Survey Mapping, British Geological Survey Records, Defra records on boreholes and water wells, and data held by the local council on private water supplies.
A total of 41 possible monitoring locations were identified across the 11 valley fens for further investigation by site walkovers. Discussions with landowners by Natural England and the visual identification of unmapped features during the walkover, led to a final total of 60 potential locations being visited.
Walkover visits were undertaken between 17 June 2024 and 17 July 2024. Sampling locations were ‘scored’ based on accessibility, infrastructure and year-round sampling viability. Locations given the highest score were considered most suitable for use as monitoring locations. The locations were further assessed based on their proximity to one another, their spatial distribution and representation of surrounding land uses.
Primary (21) and secondary (10) (backup) sampling locations were then selected and are presented for each mire along with justification for their determination.