AN APPROACH TO HYDROGEOLOGICAL
ASSESSMENT OF QUATERNARY DEPOSITS IN THE UK
Project funders/partners: SNIFFER, Environment Agency, Scottish
Environment Protection Agency, Environment & Heritage
Background to research
Superficial deposits are an important moderator of potential recharge
to a bedrock aquifer and they form a key component of the vulnerability
of that aquifer to pollution. Understanding the
processes by which superficial deposits transmit recharging water to
the water table and how the deposits attenuate pollutants as the water
passes through them is a vital component of the characterisation of
groundwater bodies as required by the Water Framework Directive.
Superficial deposits may modify both storage and vertical transport of
recharge. In particular:
Objectives of research
- the quantity of recharge
(and/or its spatial distribution) to the underlying aquifer;
- the vulnerability of the
aquifer to pollution (absorption potential of the deposits,
i.e. presence of clay minerals and/or organic material such
- the characteristics of the
groundwater system (especially aquifer storativity);
- groundwater quality
(infiltration moving downwards through these deposits to the underlying
aquifer may mobilise solutes).
The project aims to improve the understanding and analysis of the
hydrogeological processes pertaining to recharge and attenuation that
occur in the Quaternary superficial deposits in the UK. The
This report (Part 1) presents a background to the issues and a summary
of current knowledge, and includes:
- to develop a fit-for-purpose method for improving the
current hydrogeological understanding of Quaternary deposits;
- to provide a longer-term strategy to develop this method to
satisfy the increased hydrogeological understanding of superficial
deposits that will be required for many elements of the Water Framework
Directive, including further characterisation, monitoring site
selection, and programme of measures.
The main components of the developed project methodology, future
application and development opportunities are described in the
accompanying Part 2 report.
- a review of approaches taken to Quaternary hydrogeological
interpretation within the UK and elsewhere; and
- identification and description of the key factors for
Quaternary hydrogeological assessment of water bodies as required by
the Water Framework Directive.
Key findings and
The scale-independent methodology has been trialled for the whole of
the UK and compared against existing assessments of groundwater
recharge and groundwater vulnerability. These comparisons
show that the methodology produces broadly similar results to existing
assessments. However, the methodology follows a rigid and
defensible protocol and as such is an attractive alternative to
existing schemes. It is recommended that the methodology be
used to populate a new database, derived from 1: 50 000 scale input
data, in order to develop a useable vulnerability assessment to assist
in the further characterization of groundwater bodies.
Quaternary, recharge potential, absorption potential, groundwater
vulnerability, hydrogeological domains.
Copies of this report are available from the Foundation, in electronic
format on CDRom at £20.00 + VAT or hard copy at
£40.00, less 20% to FWR members.
The report is available for download from the SNIFFER Website