ONE of Scotland s top companies has accused the Scottish Government of threatening its competitiveness by scrapping a scheme that helps firms switch their goods from road to rail.  Highland Spring (HS), the UK s biggest supplier of bottled water, also says ministers  actions are  absolutely inconsistent  with their own environmental policy by ending the ?7 million-a-year Freight Facilities Grant (FFG).  The firm has been working for more than a year on plans for a rail terminal at its Perthshire base, but the closure of FFG this april means the scheme is no longer commercially viable.  It will continue to send 10,000 HGV lorryloads a year on to the roads around auchterarder instead of switching water destined for the English market to rail.  Started in 1974, FFG has paid companies up to 75% of the cost of new rail works.  as part of his draft budget two months ago, Finance Secretary John Swinney closed FFG to new applicants from april. annual Government support for freight will fall from ?10.3m to ?2.9m.  The end of FFG also jeopardises plans for a railhead next to William Grant s Girvan distillery.  In a letter to Holyrood s Transport Committee, HS said there is a clear environmental case for moving to rail, but it is only viable with grant support.  Supermarkets, which are among its biggest customers, want suppliers to be greener,  so not only could the scrapping of the FFG ... compromise the company s environmental performance, but also the future competitiveness of this highly successful Scottish business and important local employer,  it said.  Industry body the Rail Freight Group said it was  particularly concerned  by the end of FFG, which was  counterintuitive  given pledges to cut carbon emissions and to support businesses.  Government agency Transport Scotland said the decision was  regrettable  but it had to cope with a Westminster-imposed ?800m cut to its funding.