North East Area Magnesian Limestone Conceptual Model and Source Protection Zone Updates

Descriptions

We are looking for one contractor to complete work for the following two, overlapping projects: 1.NE Area Magnesian Limestone Conceptual Model (MLCM) Report update The MLCM report was originally produced by ESI Ltd consultants in 2009 and comprises of a main document, numerous appendices and a number of GIS shapefiles. The report focuses on the Permian Magnesian Limestone aquifer located in the Environment Agency's North East (NE) Area. The aquifer extends from South Shields in the North to Hartlepool in east and Darlington in the west. Since 2019 much work has been carried out by the Agency and partners, with improved knowledge of the aquifer gained therefore an updated conceptual model is required in order to consolidate and synthesise this updated understanding. Work to update the document commenced in 2020 however there was insufficient resource to complete the work in house therefore only a few sections were updated, focussing mainly on the hydrology of the aquifer and water company abstractions. Further work is required to complete an update to the conceptual model, consolidating and summarising recent understanding and ensuring all sections of the report are up to date. 2.NE Area Groundwater Source Projection Zones (SPZs) update Groundwater Source Protection Zones (SPZs) are areas of groundwater where there is a particular sensitivity to pollution risks due to the closeness of a drinking water source and how the groundwater flows. They are used to protect abstractions used for public water supply and other forms of distribution to the public such as mineral and bottled water plants, breweries and food production plants. Existing SPZs are designated across the Magnesian Limestone, Fell Sandstone and Millstone Grit/Coal Measures (Morpeth) aquifers within with the EA's NE Area. The majority of the existing SPZs were hand drawn in the 1990s, with only the Morpeth zones being completed at a later date in 2005. The conceptual understanding of the areas aquifers has changed and improved vastly over the past 20-30 years and the water environment is very different. As such, the existing zones may be significantly out of date and need reviewing and updating, where necessary. The EA is looking to procure an external contractor to deliver the work required to review and update both the MLCM report and all SPZs within NE Area. The outputs of the work will aid internal EA staff carry out various regulatory functions and help internal and external understanding of North East aquifers. The objectives of the work are: -To review, update and finalise the Magnesian Limestone Conceptual Model Report for North East Area - bringing the existing conceptual model up to date with current and updated data, literature and understanding. -To review and amend and create new groundwater Source Protection Zones for potable supplies in North East Area, across all aquifers.