Caulmert Ltd has been commissioned to produce an Environmental Impact Assessment of a proposed housing development, located close to a spring which supplies a Private Water Supply (PWS). The assessment was required to remove a condition specified in outline planning permission from the Local Planning Authority. The factors which define the vulnerability of groundwater resources to a given pollutant or activity, are the presence and nature of the overlying soil, drift deposits, nature of the solid geological strata, depth to groundwater, and nature of contaminant. All these factors were assessed to demonstrate the low risk arising from the development and where necessary low cost mitigation measures were prescribed. Consultation with the Local Planning Authority was undertaken throughout the assessment to guarantee a good outcome.