A RAILWAY organisation has written to Cambridgeshire county councillors in a final attempt to get the guided bus scheme abandoned. CAST.IRON presented the biggest objectors' case at the public inquiry in 2004 and has consistently claimed the scheme would cost more than \u00A3100million. Mark Ranger, one of the CAST.IRON executives, said: "We were ridiculed for making this claim, but it turns out we were spot on. "We also presented evidence that there would be capital and running cost overruns, leading to charges on taxpayers - this was also dismissed. "The public must keep a very close eye on the scheme as it develops." CAST.IRON's letter states that as long ago as 2000, a Government select committee had recommended the establishment of a number of demonstration projects to see if a guided bus scheme could provide a cheaper alternative to trams. Chairman of CAST.IRON Tim Phillips said: "We hope that councillors who voted for the scheme will now search their souls and realise the massive damage they are about to about inflict upon the county for no real transport gain or relief on the A14.