The EA has published an updated manual for the production of groundwater source protection zones, as well as a new webpage on gov.uk where anyone can find out where SPZs are, what defines the different zones and why the Environment Agency must protect groundwater from pollution.
The methodology in the updated manual is very similar to that in the previous report from 2009. However the report itself is set out differently, with a main report containing an introduction to SPZs, followed by the process for producing SPZs. This is followed by appendices describing the technical background of SPZs, and the technical process, such as modelling, of producing SPZs. Finally, unlike previous versions of the manual, this update includes a number of case studies.
The guidance and background to SPZS, including links to maps and the manual are on this page:
https://www.gov.uk/guidance/