Contaminated land and groundwater at St Leonard’s Court, Sandridge

We know that many of you are aware of contaminated land and groundwater issues
at St Leonard’s Court. We have written this letter to explain the history behind these
issues for any new residents, and to provide an update for all residents on the
current situation.

History: In May 2000, Three Valleys Water (renamed Veolia Water Central in July
2009) identified high levels of bromate in a public water supply borehole in Hatfield.
In high levels, bromate can be harmful to people’s health, so as a precaution Three
Valleys Water stopped using this source of water. As soon as we were aware of this
problem, we worked together with Three Valleys Water, St Albans District Council,
Welwyn Hatfield District Council and Hertsmere Borough Council to carry out water
monitoring in the area. We ensured that any other boreholes with bromate readings
above a safe level were taken out of use.

The results of our monitoring suggested that the source of the contamination was
likely to be in the Sandridge area. As a result, Komex, environmental consultants
working on behalf of St Albans District Council, carried out an investigation. In
November 2000, St Albans District Council announced their findings - their report
identified St Leonard’s Court as the source of groundwater pollution. The pollution
came from a chemical plant which was located at St Leonard’s Court between 1955
and (approximately) 1980. This plant manufactured a number of chemicals, including

In September 2001, Hertfordshire Health Authority advised St Albans District Council
that, as long as the groundwater was monitored on a continuous basis, in case the
amount of contamination fluctuated, and that the ventilation and concrete floors of
houses were checked thoroughly, risks to health would be extremely remote.
History of legal proceedings: In contaminated land incidents, we follow the
principle that, where possible, the polluter pays for any clean-up.


Following an extensive investigation, on 14 November 2005 we served a remediation
notice on the two companies we considered responsible for the pollution, Redland
Minerals Limited (Redland) and Crest Nicholson Residential PLC (Crest). Redland is
the legal descendant of the chemical plant that operated between 1955 and
(approximately) 1980. During this time, waste liquids and spillages leaked into the
ground and caused pollution. Crest, a developer of residential properties, bought the
site from Redland in 1983. They demolished the buildings, and in 1986 carried out
excavations which only removed some of the contamination.

The remediation notice that we served to Crest and Redland required them to
investigate and monitor the contamination, to remove contamination from the aquifer
(water stored in layers of rock underground) by pumping it from Veolia Water
Central’s borehole in Hatfield, and to investigate the potential for similar pumping
closer to St Leonard’s Court. Both companies appealed against the remediation
notice. The notice was suspended while the appeal was determined. The appeal was
heard at a public inquiry between 16 April and 8 May 2007. On 22 July 2009 the
Secretary of State for the Environment decided to uphold the remediation notice we
recommended, but to vary Crest and Redland’s share of the responsibility.

Crest and Redland challenged the Secretary of State’s decision in the High Court by
requesting a judicial review. Their applications were refused at a hearing in February
2010 and as a result, the remediation notice came into force on 4 February.


Current situation: Since 4 February 2010, Crest and Redland have already
complied with seven of the twelve actions in the remediation notice, and are currently
in the process of complying with the remaining five actions. Between 2001 and May
2010 we monitored the extent and concentration of the pollution so we could detect
any significant changes and ensure the risk to human health was still low. Since May
2010 Crest and Redland have taken over responsibility for this monitoring. They
have chosen to use the same contractors to carry out the monitoring as we did, so
the same company will continue to visit St Leonard’s Court. Crest and Redland will
also pay for the pumping of contaminated groundwater at Hatfield. Both of these
actions are part of the remediation notice.


For the foreseeable future, there will be very few changes at the site which will affect
residents. In the longer term (years or even decades), we cannot rule out the
possibility that we may need to carry out a site investigation at St Leonard’s Court.
However, if this is the case we will let you know about any works well in advance of
our start date and will do everything we can to minimise the disturbance to residents.


I hope you have found this information useful. To read previous updates we have
sent out, please visit Beechgrove’s website at If you
have any questions, please contact me.


Yours faithfully


Ally Riley
Technical Officer, Groundwater and Contaminated Land Team
Direct dial 01707 632 585
Direct email This email address is being protected from spambots. You need JavaScript enabled to view it.
External Relations
Apollo Court
2 Bishop Square Business Park
AL10 9EX
Tel 01707 632468