Hi Neil,
I would of though the stabilisation might release more CO2 for a period?
Depends on the binder? With regards to releasing all the gas, that
depends on what the potential is for further gas generation and
dependant of the constituents of the made ground.
Maybe ask them to do some post stabilisation gas monitoring prior to
starting to build. If it does what they say it does, then maybe no gas
protection measures are required, if it doesn't then they need to
reconsider their position.
Remember the new CIRIA guidance on ground gas will change the way we
approach gas risk assessment and may have a bearing on low gassing
sites.
Merry Christmas,
John Naylor
Senior Environmental Protection Officer
Bury M.B.C.
*: 0161 253 6392
*: 0161 253 5563
*: [log in to unmask]
* Environmental Services, Textile Hall, Manchester
Road, Bury BL9 0DG
* www.bury.gov.uk
-----Original Message-----
From: Contaminated Land Management Discussion List
[mailto:[log in to unmask]] On Behalf Of Brown,
Neil
Sent: 21 December 2006 11:32
To: [log in to unmask]
Subject: Ground gas remediation
We have a development site overlain by approximately 3m of made
ground. Ground gas investigation has shown that the site is producing
between 0 - 3% methane and 0 - 5% carbon dioxide over 3 rounds of
monitoring.
The made ground requires stabilisation before the development
goes ahead. The stabilisation involves excavating the made ground,
conditioning with a binder agent (including lime) and replacing in
compacted layers.
The developer's engineers are stating that any trapped ground
gas will be released during the excavation and any further carbon
dioxide generated will react with the lime to from an inert compound.
They therefore consider that gas preclusion measures are not required.
Does anyone have any experience of this technique and whether it
actually works? My feeling is that validation would be required once the
made ground has been compacted and the platform is ready for
development.
Any help would be appreciated.
Merry Christmas and Happy New Year to everyone!
Neil
Neil Brown
Contaminated Land Officer
Development Planning
Development and Regulatory Services
West Lothian Council
County Buildings
LINLITHGOW
West Lothian EH49 7EZ
Tel. 01506 775263
Fax. 01506 775265
Email. [log in to unmask]
West Lothian is the UK Council of the Year 2006
________________________________________________________________________
This message, together with any attachments, is sent subject to
the
following statements:
1. It is sent in confidence for the addressee only. It may
contain legally privileged information. The contents are
not to be disclosed to anyone other than the addressee.
Unauthorised recipients are requested to preserve this
confidentiality and to advise the sender immediately.
2. It does not constitute a representation which is legally
binding on the Council or which is capable of constituting
a contract and may not be founded upon in any proceedings
following hereon unless specifically indicated otherwise.
http://www.westlothian.gov.uk
________________________________________________________________________
This email has been scanned for all viruses by the MessageLabs
SkyScan
service on behalf of West Lothian Council.
For more information on a proactive anti-virus service working
around the clock, around the globe, visit
http://www.messagelabs.com
________________________________________________________________________
