The news comes as the militant Joint Sites Committee, which has also been campaigning against Tarmac and its subsidiary Schal, announced that it would be seeking an alliance with environmentalists to co-ordinate action against the company.
Members of the Joint Sites Committee met a group of environmental activists before last week's Carnival Against Capitalism in London's Square Mile, which ended in mayhem after protesters and police clashed.
The environmentalists distributed hundreds of leaflets during Friday's demonstration calling on other activists to take part in what the leaflet described as The Big Day Out against Tarmac.
The leaflet listed a telephone number that activists could use to find out more.
A Joint Sites Committee insider said that a number of members would attend the day of action.
The insider said: "Building unions could learn a lot from what happened in London last Friday. There is no point in winning pay increases if construction workers keep building houses that only a small percentage of the population can afford to live in, or end up choking to death on car fumes."
A member of the militant environmental group Earth First said: "Tarmac is going to be targeted because it is destroying Bestwood County Park. We also don't like the fact that it is involved in building private finance initiative prisons or the construction of GCHQ, which monitors [environmental] groups and activists."
The activist refused to say what form the action would take, but said it would involve a number of environmental groups, which intended to join forces with local activists.
Tarmac has had planning approval to quarry a site next to Bestwood County Park in Nottingham for 30 years, but has only recently taken steps to start work.
A spokesman for Tarmac said the company was unaware of any specific threats, but said it was always vigilant.
The spokesman said Tarmac had told Nottingham County Council that it would donate the Bestwood site to the local community if it was given permission to extend other quarry sites.
He said Tarmac chairman Sir John Banham had held talks with people living beside the site. "We believe we have a good dialogue with the local community," the spokesman said.
The Joint Sites Committee had singled out Tarmac and its construction management subsidiary Schal because it claims they are opposed to union-recognised safety representatives.
However, Schal denies this and said that it enforces safety rigorously.
Tarmac says it has one of the best environmental records in construction, and has an external committee of advisers that audits businesses within the Tarmac Group.
Senior executives now believe that the firm would not bid for projects similar to its notorious M5 extension through Twyford Down. It was this project more than any other that earned Tarmac a reputation for being environmentally unsound.
