Maybe we should thank al-Qaeda for prompting the authorities to carry out this survey. From AP, Sept. 22:

WASHINGTON - Anti-terrorism officials conducted a helicopter survey of New York City's radiation sources in preparation for a so-called “dirty bomb” attack - and discovered a Staten Island park with dangerously high levels of radium, a new report found.

Federal authorities found 80 unexpected “hot spots” around New York City, according to the Government Accountability Office, the investigative arm of Congress.

The GAO report released Thursday details a previously undisclosed aerial anti-terrorism program in New York City, one which may be extended to other cities worried about the possible release of radioactive material by terrorists.

The report does not identify which city park had the contaminated soil, but NYPD officials said it was in Gateway National Park in Staten Island.

The site was closed, and New York has requested federal money to do a citywide aerial survey every year to update the information.

By creating a map of the city's radiation sources, city officials hope to be able to respond more quickly in the event of a dirty bomb attack, know exactly which streets are contaminated and get civilians away.

New York is the first and only U.S. city to conduct a complete aerial radiological survey, having paid the U.S. Department of Energy $800,000 for the 2005 study.

The helicopters picked up sources of low-level radiation from expected places, like granite statues and medical isotopes at hospitals, but it also found dozens of other sources of unexpected radioactivity, the GAO report found.

“NYPD officials indicated that the survey was tremendously valuable because it identified more than 80 locations with radiological sources that required further investigation to determine their risk,” the report said.

At the Staten Island park, sensors detected large quantities of radium in the soil. Long-term exposure to radium increases the risk of developing lymphoma, bone cancer and leukemia.

A spokesman for the National Park Service did not immediately return telephone calls for comment Thursday.

Staten Island's congressman, Rep. Vito Fossella, said the contamination was a surprise to him and residents near the park, and he demanded more information.

“It is essential for the government to act immediately to fully understand the extent of the contamination,” said Fossella, who was trying to arrange a meeting Friday with federal and city officials to discuss further testing and possible removal of the contaminated soil.

The aerial survey is designed to help local officials react more quickly in the event of terrorists detonating a “dirty bomb” that releases radioactive material into the air.

With the survey, police may be able to pinpoint the exact source of radiation by comparing new readings to their pre-existing “radiation map” of the area.

NYPD spokesman Paul Browne said the department wanted a record of the city's naturally occurring and other “radiological signatures” to compare with periodic readings it does to detect for dirty bombs or other nuclear devices.

“It gives us a baseline so we can pick up any anomalies,” he said.

New York City is the only major city to conduct a full-scale Aerial Background Radiation Survey to identify “hot spots,” though such work has been done in the nation's capitol, according to the report.

The GAO found neither the Department of Energy nor the Department of Homeland Security believe they are required to conduct such radiation mapping, though the investigators said there were “significant benefits” to surveys in other urban areas.

Homeland Security officials agreed that they should study the cost and effectiveness of expanded radiation mapping in additional cities.

Sen. Charles Schumer, D-N.Y., called the report further proof the federal government is not doing enough to help cities guard against terrorism.

The hot spot mapping initiative “should also be shared with cities across the country, not mothballed because the Homeland Security Department doesn't want to put up the money,” Schumer said.

The GAO report also found the Department of Energy may need to beef up security at Nellis Air Force Base in Nevada and Andrews Air Force Base in Maryland because those sites hold key national assets for responding to a radiological or nuclear attack.

Specialized quick-response teams and equipment are concentrated at those two sites, and a successful attack against either could leave one section of the country with limited capacity to respond to a subsequent strike with radioactive weapons, the GAO said.

The agency's associate administrator, Michael C. Kane, was adamant the sites are safe.

“We categorically reject the contention that physical security at two of our facilities may not be sufficient for protecting against terrorist attacks,” Kane wrote.

See our last posts on nuclear paranoia and fear in New York City.