An extra 600 gardaí have also been drafted into Waterford for a three-day meeting of EU environment ministers, scheduled to begin on May 14.
Military sources confirm a battalion strength formation of troops has been quietly undergoing public order training at the Curragh camp and Gormanstown camp over the last month in preparation for the main event at Farmleigh.
Recent threats by radical anti-globalisation group the Wombles, to “storm
Farmleigh House” are being taken “very seriously” by the Government.
The last time troops were put on standby in strength to support gardaí in a public order situation was during the riots outside the British Embassy in the early 1980s.
The troops will be equipped with modern flame-retardant suits, helmets and visors and special public order long batons and shields.
While similar to the garda’s public order uniforms they will have distinctive army identification. But it is unlikely identification numbers will be worn.
A defence force spokesman confirmed that troops would be operating on the day “but only in support of the civil power”, the gardaí.
In effect the gardaí will be responsible for the outer perimeter security of Farmleigh House.
Garda sources say hoardings and barriers similar to those used at concert venues would be put up to assist in security.
Members of the garda tactical school from Templemore Training College will also be deployed to ensure protesters can’t chain themselves to trees.
All members of the tactical school are trained abseilers and proficient in scaling obstacles.
The army battalion deployed at Farmleigh House will be acting as the last line of defence should protesters breach garda lines.
More than 1,000 gardaí across the country have received riot training over the past 18 months.
“The gardaí and army have undergone extensive preparation for May Day with both forces bringing their personnel up to speed in contemporary public order tactical responses,” security sources said.
“Unless there’s trouble on the day however, the general public will never be aware of just how extensive the preparations are.”
In addition to providing the last line of defence at Farmleigh soldiers will also be on standby to assist gardaí in Dublin city.
It is understood garda officers at inspector, superintendent and chief superintendent rank have undergone extensive training in tactical leadership for public order situations over the last two years.
“There’ll be no repeat of Dame Street. We have the training and more importantly, the on the ground leadership in place. If there is trouble caused we are confident of containing it,” a garda source said.
Meanwhile, a major garda operation is being planned in Waterford as security experts fear the city might be a potential flashpoint for demonstrations when as many as 400 EU delegates gather from May 14 to 16.
The strength of the garda presence for the high profile political meeting will be dictated by any fallout on May Day in Dublin.