The new Indian Point emergency notification system was scheduled to go on line Thursday after passing two tests, but the Federal Emergency Management Agency is not ready to sign off on the project.

A petition by the group Riverkeeper began the process of replacing all of Indian Point's emergency sirens following the blackout in August 2003, which brought into view the lack of back-up power.

That prompted Sen. Hilary Clinton (D-NY) to sponsor legislation requiring the installation of a second power source for all of Indian Point's sirens. Instead, the owner of the power plant, Entergy, decided to completely replace the old system with a new one, which was to include text messaging and reverse 911.

But from the outset, the process of activating the siren system has been plagued with problems and setbacks.

Phillip Musegaas, of Riverkeeper, says his organization and other groups are frustrated by the delays, and he suggests Entergy should have put back-up power on the old sirens, since they've been working almost flawlessly in recent years.

?They picked an extremely complicated system, complicated software, perhaps over ambitiously, and now we?re stuck with this mess,? he says.

According to Diane Screnci, of the Nuclear Regulatory Commission, the fact that the new sirens are not yet on line does not mean the deadline had been missed.

Screnci adds, however, that once the new system is finally approved, the NRC will see whether additional enforcement action is needed.

This week, the new system was tested to allow residents living in the emergency planning zone around the nuclear power plant to become familiar with the new sirens, which have a different sound.

Click here for more on siren system test.