In relation to the article 'soil stabilisation history lesson' by Jonathan Smith of Geofirma (GE January 05) I would like to clarify some of the points made.
Under the image, showing an old aborted version of the athletics model of the City of Manchester Stadium there is reference to the stadium being built on a former gasworks site, with ground stabilised with lime/cement.
In fact, the stadium was located predominantly on the site of a former iron works and the structure is founded on piles. Lime/cement stabilisation was only used temporarily under the athletics track which was removed during the excavation for the lower seating bowl as part of the conversion for Manchester City Football Club.
The small photograph showing that stabilisation can be used for large car parking areas also features the stadium. This particular car park to the north of the stadium was located on fill which covered the former gasworks site. The larger photograph on the title page shows stabilisation taking place for temporary surfacing of the adjacent media park for the 2002 Commonwealth Games.
What is not referred to in the article, and is possibly the more novel aspect of Geofirma's involvement, is that marginal site-won material was lime stabilised for use as infill for 6m high reinforced walls to the car parking areas to avoid importing granular fill.
Colin Curtis, associate director, Arup Editor's note: The captions for the pictures were written by the GE editorial team and not by Jonathan Smith - apologies for any confusion caused.