Federal officials were most concerned about the easy penetration of security at the nation's potentially deadliest plants. At the mammoth Sony Technology Center in Westmoreland County, an unsecured gate, distracted guards and unconcerned employees let a reporter reach 200,000 pounds of chlorine gas. No one stopped him as he touched train derailing levers, waved to security cameras, and photographed chlorine tankers and a nitric acid vat. If ruptured, one Sony railcar could spew gas 13 miles, endangering 190,000 people. Two other plants penetrated by the Trib and "60 Minutes" -- Univar and Millennium Chemical in Baltimore -- each put more than 1 million neighbors at risk of chlorine poisoning.

In February, Homeland Security Secretary Tom Ridge issued a bulletin warning that "al-Qaida operatives may attempt to launch conventional attacks against U.S. nuclear/chemical-industrial infrastructure to cause contamination, disruption and terror." When told how the Trib and "60 Minutes" easily punctured plant security in several states, he was concerned but expressed optimism that long-term federal reforms will protect Americans from toxic catastrophes.

"I think what we need to understand is that this enormously complex and diverse economy, worth trillions of dollars, has many potential targets," Ridge said. "And we have to begin to understand that we can't eliminate the risk. We have to manage the risk. And the way we manage the risk is by starting to take a look at those that are most vulnerable, whose use or destruction could result in a catastrophic loss of life or economic damage."

Ridge said federal teams recently began scrutinizing security deficiencies at "nearly two dozen" facilities the agency considers most tantalizing to terrorists. On Friday, Homeland Security announced that National Guard troops had visited about 150 sensitive sites, of which "more than half" were chemical facilities. Details of the visits were not disclosed.

But the plants' neighbors want tighter security and more openness about potential dangers sooner, not later.

"They've never told us anything about the chlorine there. I've never even heard they had all of that there," said Nancie Bluebaugh, of East Huntingdon, who lives a few blocks from Sony. "I have a child here. We see the trains coming and going, but we had no clue what was in them.

"I'll do a lot of praying now."

Yvette Leto, who lives a few blocks downwind from Neville Chemical's boron trifluoride, believes federal agencies should outlaw catastrophic chemical storage near cities. According to Neville's filings with emergency planners, the plant also could unleash deadly hydrogen fluoride, anhydrous ammonia, benzene, styrene, phosphoric acid and 10 other toxins that burn flesh, blind eyes, flood lungs with blood or cause cancer.

"The big shots who run the corporations aren't worried about us," Leto said. "They're fine because they don't live here. Are they willing to come down and live next to these plants, like we do? I bet they wouldn't do it. But they'll put the chemicals here."

Neville Chemical officials would not comment.

Frank Leto, Yvette's father-in-law and next-door neighbor, believes federal regulations should balance the risk of disaster with the need for well-paying manufacturing jobs. A retired Aristech and Pittsburgh Coke and Chemical employee, he said the chemical industry keeps the Neville Island economy afloat.

"I worked there for 50 years, so I know how dangerous chemicals can be," he said. "But you can't have it both ways. People complain about the dangers and the smells and all that, but they'd complain even more if the companies packed up and left town."

Reforms fail

When told of the latest incursions by the Trib and "60 Minutes," most plant officials immediately pledged for the second year in a row to investigate security snafus.

AK Steel authorities said they always work to improve security, citing a $25 million upgrade that recently reduced use of nitric acid at two Butler plants. AK also installed dikes to significantly reduce hydrofluoric acid dangers.

Giant Eagle immediately repaired a broken fence and assured the Trib no one else would reach its chemicals.

After a reporter spent more than 20 minutes probing sensitive purification rooms, Oakmont Water Authority officials vowed to add gates to block access to their Hulton Water Treatment Plant. In Beaver, a township supervisor and the Chippewa Township Sanitary Authority have discussed placing the water-treatment plant under tighter vigilance.

Several Pennsylvania facilities failed the Trib's latest test even after major security upgrades since 9/11.

After last year's incursion by a Trib reporter, the Wilkinsburg Penn authority spent more than $100,000 scripting a security plan and adding electric gates, camera detectors and worker identification badges at both the Tyler Road treatment plant and a pump station along the Allegheny River.

But a Trib reporter twice scooted through a fence hole and an unlocked door that led to 20 tons of chlorine gas. The treatment plant and its Nadine Road pump station suffer from century-old layouts that are perfect for saving money on utility operations but difficult to secure from intruders.

"I've been here 23 years," said Wilkinsburg Penn director Mark Lerch. "Back then, security was never an issue. The water treatment was out of sight, out of mind. But 9/11 showed our vulnerability to terrorists. They can hit our natural gas or our electricity and we will survive. But you can't go without water."

Lerch lectured workers on lax security and tightened plant perimeters.

After a Trib reporter penetrated Univar's security last year, the company erected high fences at its Bunola yard, instituted round-the-clock guards, installed cameras and even fortified its river dock, making the works impregnable from nearly every direction -- except the railroad.

Managers asked the rail line to let them fence off track where a chlorine tanker parks daily. But federal safety laws wouldn't allow it. So the Trib and "60 Minutes" were able to make four undetected trips up the rails to 90 tons of chlorine gas.

"We really have done everything we can to make our facility secure," said Univar manager Cliff Moll. "I really think we went the extra mile and did everything anyone could do. But we can't do anything about the railroad."

The extra mile?

At other plants, workers and neighbors questioned whether management had done anything to stiffen security since the Trib's visits last year.

A reporter easily canvassed the sprawling Allegheny Ludlum mill in Brackenridge three days in a row, following a path down a bluff, across the railroad, behind a guard shack and up to 100,000 pounds of hydrogen fluoride, a lethal toxin used to "pickle" stainless steel.

Longtime Brackenridge employees blamed lax security on recent guard cutbacks and indifference. If released, the mill's acid could waft nearly a mile and threaten more than 16,000 residents with blindness, severe burns and death. A spill also would jeopardize water supplies drawn from the Allegheny and Ohio rivers.

Allegheny Ludlum officials declined to comment.

"I know they put in surveillance cameras, but we don't know if anyone is really watching," said Gerard Magoc, a Brackenridge steelworker for 31 years. "They put on a big show about searching cars, though. They're big on theft. ... They care more about protecting their toilet paper than they do about their hazardous materials."

James Austin Co. managers also didn't discuss breaches.

On Oct. 28, EPA officials asked Austin to resubmit disaster plans, citing inaccurate estimates of the population endangered by its railcars. The bleach manufacturer claimed a chlorine plume could reach 12 miles, affecting only 5,500 people in the North Hills and Butler County. Trib research of U.S. Census figures, however, shows that the gas endangers 260,000 neighbors, making Austin one of the 700 potentially deadliest plants nationwide.

Sony officials said they would have "locked down" the East Huntingdon yard had the FBI warned them a terrorist or reporter was coming. Because Sony is in a rural area, corporate authorities believe it isn't a likely sabotage target.

"We respond to a threat if it's reported to us," said Sony security director Tim Pratt. "We can close the place down if something happens."

Since the Trib's surprise visit last year, Sony officials have added a concrete bulwark, metal fences and a video camera to aid security at their chlorine railcars, where a rupture would endanger 190,000 people.

Counterterrorism experts say that's not good enough. They increasingly advocate the use of barbed wire, heavily armed guards or technologies that reduce or eliminate the threat of toxic releases -- security standards common to the nuclear industry because of federal regulations.

"We might as well face the fact that security at a 7-Eleven after midnight is better than that at a plant with a 90-ton vessel of chlorine," said John DePasquale, a former Georgia-Pacific Corp. security chief who now consults with industry. "A guy with a suitcase full of explosives can kill tens of thousands of people, and we're not doing anything about it."