At least 18 times in the past three years BNSF Railway freight trains rolled west out of Minneapolis pulling cars filled with hazardous chemicals that were not on the trains' official cargo list, according to train crew complaints.

That's contrary to federal regulation because in case of an accident, local firefighters can be left in the dark, unable to take quick action to protect vulnerable residents.

In one case, a train traveled more than 20 miles through the western suburbs with six carloads of anhydrous ammonia, a toxic corrosive gas used as a farm fertilizer, before the train crew knew the chemical was on the train, a complaint said. In another, a complaint said a train traveled about 90 miles west to Willmar before its cargo list — called a manifest — was corrected to show an extra car of ammonia.

The complaints were filed with the Federal Railroad Administration, the federal agency that regulates railroads, and they provide a snapshot of one rail line across Minnesota, a BNSF Railway line from Minneapolis to Willmar. BNSF is the largest rail operator in Minnesota. Provided to MPR News by railroad union members, they are evidence of a problem the FRA said poses "unreasonable risks to health, safety and property."

Hauling hazardous material without proper documentation is a problem federal officials have been aware of for years. When federal inspectors checked manifests of all rail haulers in Minnesota over a three-year period, one in five contained inaccurate information about cars hauling hazardous materials, according to FRA records obtained through a Freedom of Information Act request.

Khalid (last name withheld), right, and Zakariah Rasheed, 7, play soccer in their backyard near the BNSF rail line in Willmar, Minn. Jackson Forderer / For MPR News

'The bible' for first responders

Nationwide, railroads moved about 2.2 million cars of hazardous chemicals last year. That's about 6 percent of all rail traffic, according to the American Association of Railroads.

Virtually all arrived safely at their destination. Thousands of trains move on the Minneapolis-Willmar line every year without incident.

But the stakes are high because of the large volume of hazardous materials carried in a single rail car.

Sometimes train cars that can be carrying anhydrous ammonia or phosphoric acid, for example, are temporarily lost in the system. Computer glitches or other mistakes can result in cars getting added to the wrong train or in not getting included on the manifest the crew carries.

A good safety record, but accidents happen

Nationally in 2012 and 2013, accidents caused rail cars to release hazardous material 46 times. One of those accidents was near Casselton, N.D., where a BNSF oil train collided with a derailed grain train and burst into flames.

Two of those releases (in orange) were in Minnesota. A Canadian Pacific oil train derailed near Parker's Prairie last year, spilling 15,000 gallons of crude oil. A SOO line car released 28,000 gallons of benzene dicyclopentadiene near Plummer in northwestern Minnesota in 2012.

Minnesota had 45 other rail accidents (in blue) in those two years that involved hazardous materials rail cars but released no chemicals.

If a train derails or is involved in a crash, the first thing firefighters arriving on the scene look for is the train manifest because it tells them which cars carry hazardous material and their position in the train.

•Related: Combined response to a hazardous waste spill in the middle of the night

The hump control tower overlooks the BNSF Northtown Yard in Minneapolis. Jeffrey Thompson / MPR News

Without a correct manifest in the event of an accident, "you're sending fire and rescue in there, and they have no idea what they're getting in to," said a BNSF employee who spoke on condition of anonymity because train crews aren't allowed to speak with reporters. "And they could literally walk into an extremely deadly situation." BNSF declined to make available for in-person interviews Thomas Albanese, general manager of its Twin Cities division; Phil Mullen, director of safety and transportation for the railroad, or other officials.

Minnesota Department of Transportation Senior Rail Planner Dave Christianson calls the train manifest "the bible" for first responders.

If the manifest is inaccurate, "It basically nullifies any preparation that has ever been done to protect the public and to respond to a catastrophic incident," said Christianson, who has experience as a hazmat firefighter. "That document is the key to how emergency responders react to the accident."

The problem of inaccurate manifests starts when trains are assembled. In the case of the BNSF line from Minneapolis to Willmar, many of those are built at the Northtown rail yard, what's known as a hump yard, in northeast Minneapolis.

Hundreds of rail cars pass through the yard every day. Cars from inbound trains or local customers are sorted for their outbound destination based on computer lists. Each rail car has an electronic tag that identifies it.

Workers use "the hump," a slight hill in the yard that allows them to take advantage of gravity, and a series of track switches and braking devices to sort cars onto about 50 tracks, creating new trains.

Some common hazardous chemicals hauled by rail

Identify rail car contents by placard numbers.

1005 -- anhydrous ammonia - widely used source of nitrogen fertilizer, one of the most potentially dangerous chemicals in farming.

1017 - chlorine - greenish, yellow gas used to purify water, bleach wood pump and make other chemicals. Toxic to inhale.

1075 - liquefied petroleum gas - fuel, aerosol propellant, used to make other chemicals. Heat can cause rupture.

1170 - ethanol - alcohol generated from grain and used as fuel for vehicles.

1203 - gasoline - vehicle fuel.

1789 - hydrochloric acid - used in production of fertilizers, dyes and other chemicals and in electroplating. Corrosive to eyes and skin.

1824 - sodium hydroxide - used in textiles, pulp and paper, soaps and detergents and for electroplating. White solid that absorbs moisture and is corrosive.

1830 - sulfuric acid - colorless liquid used in fertilizers and in petroleum refining. Corrosive to metals and tissue.

2448 - molten sulfur - used in sulfuric acid production, petroleum refining and pulp and paper manufacturing. Yellow crystalline, causes burns on contact.

Want to identify chemicals on rail cars or trucks? Download the iPhone or Android app created by the Pipeline and Hazardous Materials Safety Administration (PHMSA).

When the system works properly, the process creates a manifest as cars are added to a train. The manifests are kept in a computer and given to train crews as they leave the yard.

Feds try to get tougher

In 2005, two Canadian National trains collided head-on near a small Mississippi town. The locomotives caught fire, and all four crew members in the trains died. It took more than two hours for the railroad to provide manifests to firefighters, and one manifest failed to properly identify hazardous materials on the train, the National Transportation Safety Board found.

In 2007, the NTSB issued a safety recommendation to "require that railroads immediately provide to emergency responders accurate, real-time information regarding the identity and location of all hazardous materials on a train."

Last year, the FRA and the Pipeline and Hazardous Materials Safety Administration reported that they were working on regulation changes to address the recommendation. They are also testing electronic train manifests to replace the paper copy now used.

In 2006, the FRA conducted a nationwide audit and found 14 percent of trains inspected had inaccurate manifests, showing cars loaded with hazardous materials in the wrong position or failing to show hazardous materials that were on the train. The report said the inaccuracies resulted when trains were assembled or when cars are added or dropped along routes.

Fishermen work the shoreline of Lake Minnetonka as a train passes in downtown Wayzata. Jeffrey Thompson / MPR News

"By far, the presence of undocumented shipments of hazardous materials poses the greatest danger during transportation," the agency concluded.

"Railroads will be advised that compliance is required immediately," the FRA report said. "No grace period for attaining compliance will be provided."

The FRA has done more audits since then but declined to release the results. Records that MPR News obtained from the FRA through a Freedom of Information Act request show that over the three years from 2011 through 2013, when inspectors checked train manifests in Minnesota, 20 percent had inaccurate information about hazardous materials on the train. That's a violation rate slightly higher than was found in the national 2006 FRA audit.

Seth Novak mows his lawn in Benson, Minn., as a BNSF train passes through town. Jackson Forderer / For MPR News

The FRA refused several interview requests for this story, but public affairs specialist Michael England provided a statement by email:

"Inaccurate train documents of extra/undocumented hazmat cars poses (sic) unreasonable risks to health, safety, and property when in a derailment or emergency situation. When FRA observes extra cars missing cars, or an inaccurate wheel report describing hazmat cars in transportation, FRA is very concerned and will usually cite the RR(railroad) for generating an incorrect train document."

BNSF's Northtown yard

BNSF Railway, owned by Warren Buffett's Berkshire Hathaway holding company, is one of the nation's largest railroads and the biggest freight hauler in Minnesota.

In the 2006 national audit, the railroad had a train manifest violation rate of 8 percent, lower than the national average for the nation's largest railroads.

An automatic equipment identification reader documents train car information along the BNSF line in Fridley, Minn. Jeffrey Thompson / MPR News

But records show BNSF has had an ongoing problem with trains leaving the Northtown Yard with undocumented hazardous materials.

FRA inspectors met several times with BNSF about the issue in the past three years. And the FRA confirmed that in June 2012, FRA Region Four Administrator Michael Long met with BNSF officials in Minneapolis to discuss inaccurate manifests and other safety concerns. The agency recommended adding electronic scanners to verify the manifest's accuracy as the cars leave the rail yard.

In an email exchange, BNSF Railway spokeswoman Amy McBeth confirmed there are three scanners at the Minneapolis rail yard, including one that scans every train leaving the yard. BNSF considered installing a fourth scanner but decided it was not necessary. The railroad "implemented process improvements over the past year," in consultation with the FRA, McBeth wrote. "There are checks and balances deployed through the process to ensure the proper train consist, (manifest)."

An internal BNSF document from September 2013 provided by a worker indicated problems with the electronic scanner technology. The memo said scanner programming was being tested and would be installed once accuracy could be verified.

The FRA also recommended a rail yard worker be assigned to check trains as they leave the yard, visually verifying the train manifest.

A placard indicating liquefied petroleum cargo is displayed on a train car in the BNSF Northtown Yard. Jeffrey Thompson / MPR News

McBeth said that suggestion was implemented. But rail yard workers contend the employee assigned to check outbound trains is sometimes given other tasks and often does not receive a list of cars before trains leave the yard.

An FRA inspector raised the same concern in 2012 after spending two days observing operations at the Northtown Yard.

The United Transportation Union, which represents some 125,000 rail, bus and transit workers in the country, provided MPR News with copies of 18 complaints filed on behalf of BNSF employees alleging train manifests didn't properly account for hazardous chemicals. One, from February 2011, said a train was pulling six cars of anhydrous ammonia that were not on the train manifest. The mistake was found and the manifest corrected 24 miles down the track after rolling through Minneapolis and several western suburbs.

In another case, in April 2012, a train left Northtown Yard with an extra car labeled phosphoric acid. The car was added to the manifest as the train passed through Wayzata.

The mistakes are often found when trains pass one of the electronic scanners along the track. If a scanner finds an extra car, the updated information goes to a railroad dispatcher, who then tells the train crew to correct the paper manifest they carry.

"From the time it departs, the train could go from northeast Minneapolis all the way into the suburbs before anyone would realize that the list is incorrect," said a BNSF employee who spoke on condition of anonymity for fear of retaliation.

A BNSF train engine sits near downtown Willmar, Minn., before heading west. Jackson Forderer / For MPR News

"Sometimes you'll get notified right away, sometimes you might be 50 or 60 miles down the road before they get to you."

'You get a target on your back...'

The complaints filed by the union usually provide the FRA with the names of the train crew. Some of the incidents reviewed by MPR News were substantiated by the FRA but in other cases employees wouldn't talk to federal inspectors, and the investigation was stopped.

In January 2014, for example a BNSF train left the Northtown Yard headed toward Willmar, one complaint said.

The manifest showed 56 cars. But later documents show the train had 57 cars. The extra car, loaded with ammonia, was not added to the list until the train arrived in Willmar.

A crew member turned over documents to the union, which filed a complaint with the FRA. Despite the paperwork showing the mistake, the agency, which typically requires an interview with the train crew to verify that a problem occurred while the train was moving, said it was unable to substantiate the claims that the train manifest was wrong. That happened in a number of the cases MPR News learned about because crew members declined to talk to federal investigators on the record.

In interviews, several crew members said they fear if they participate in investigations the railroad will retaliate.

"If you're a safety advocate, you get a target on your back," said one crew member.

There is currently a federal whistleblower lawsuit involving a Minnesota BNSF worker who contends he was fired for raising safety concerns.

Phil Qualy, the United Transportation Union's state legislative director, said fear of retaliation often keeps workers from reporting these safety issues.

"I will always stand as a director to say to our members that if you feel uncomfortable, that you're putting your livelihood on the line, then you don't have to give a statement," said Qualy, who is a former railroad conductor.

Inspectors stretched thin

Inaccurate train manifests are most likely to be found by train crews, because federal inspectors are stretched thin. A 2013 General Accounting Office report said FRA inspectors cover less than 1 percent of regulated railroad activity.

The agency has 400 inspectors assigned to eight regional offices. They inspect track, signals, equipment, operations and hazardous materials.

A BNSF train passes through a train yard in Willmar, Minn., at dusk. Jackson Forderer / For MPR News

Eight hazardous materials inspectors work out of the Chicago office, covering five Midwestern states.

Concerns about the increasing shipment of North Dakota crude oil across the state prompted the 2014 Minnesota Legislature to approve funding for a new state hazardous materials inspector. That inspector should be on the job late this year, helping to enforce federal rail regulations.

MnDOT's Dave Christianson said inaccurate train lists will be a "key target" for the inspector.

Documents

Excerpts from a Federal Railroad Administration inspection report of a BNSF train.

Complaint filed by the United Transportation Union alleging improper documentation for a rail car carrying anhydrous ammonia

The Federal Railroad Administration response saying the complaint could not be substantiated in response to the complaint filed by the United Transportation Union.

BNSF letter to the Federal Railroad Adminsitration documenting improvements the railroad made.