SEGH Articles

Environmental Public Health Tracking Proof of Concept Study: hazard tracking in private drinking water supplies

01 October 2011
The Health Protection Agency undertook a proof of concept study to appraise the chemical quality of private drinking water supplies in East Cornwall and map their metal and mineral content relative to geological formation.

 

The HPA's Centre for Radiation, Chemicals and Environmental hazards (CRCE) has embarked on one of the first studies of its kind in the UK - to map the levels of metals and minerals present in geological formations and their potential effect on the quality of private drinking water supplies.

The team, working in collaboration with colleagues from Cornwall Council and the British Geological Survey (BGS), identified, collected and analysed samples from approximately 250 homes with private drinking water supplies in East Cornwall.

The study aimed to improve the knowledge of the quality of private drinking water supplies in the area and increase the understanding of where high levels of naturally occurring metal and minerals are present in the ground. The data collected will be used to map levels and their potential distribution.

Prior to the ground work, BGS identified key geological formations in the sampling area to identify areas with the potential for high yields of metals and minerals in underground water supplies.  The study will help identify where levels of metals and minerals are highest in specific geological formations, this will inform where future water tests would be most appropriate and where resources could be targeted most effectively.  If any private water supplies are found to have levels above the statutory limits, special treatment at the source will be advised to reduce the levels and make the water safe to drink.  If successful, the study could be rolled out to help other local councils meet their duty under the Private Water Supply Regulations across the country.

The study consists of several stages through design, scoping and delivery and involved four weeks of intensive logistical planning and contact with residents to arrange appointments and to gain access to their private water supply for sampling.  Sampling int he Spring involved a 17 day programme with BGS visiting over 250 homes and taking around 300 water samples from borehole supplies across East Cornwall. Samples were analysed for around 60 specific metals and minerals, the outcomes will be reviewed and results fed back.

When the results of the analyses are available (September 2011) they will be used to inform environmental and public health assessments and form the basis for modelling population risk.

Becky Close: Environmental Public Health Scientist, Centre for Radiation, Chemical and Environmental Hazards,

Health Protection Agency.  Rebecca.Close@hpa.org.uk

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