The feds want a system installed that allows a computer to reduce a train's speed in a number of situations. The MTA trains are already equipped with a similar system, but it kicks in only when one is in danger of crashing into another.
The money would come from the MTA's 2010 capital program, the budget that funds mega-projects like the Second Avenue Subway and currently has a $10 billion funding gap.
"It's a lot of money," said Bill Henderson of the Permanent Citizens Advisory Committee to the MTA. "And my belief is that the MTA's railroads are substantially safer than many of the similar ones in the rest of the nation."
Metro-North hasn't seen a passenger die from a train crash in its 27-year history. The LIRR hasn't had a fatality since the 1950s. Still, Congress mandated in October 2008 that all commuter railroads in the country install what's known as positive train control after 25 people died in a California crash.
But that California railroad -- like most others in the nation -- was using far less sophisticated equipment than the MTA's, sources and documents say. Now LIRR and Metro-North -- the country's first- and second-largest systems -- have until the end of 2015 to install the safety measures.
In-house MTA lobbyists have already asked the Federal Railroad Administration for an exemption.
The new system would have "marginal benefit" and "introduced significant cost and risk to a rail system which currently has a high degree of safety," MTA Deputy Executive Director Chris Boylan wrote to the feds this month.
But Metro-North and LIRR's current systems "do not have the same capabilities of a fully integrated positive train control system," said Warren Flatau, an FRA spokesman.