Tag Archives: Positive Train Control

Benicia City Council to consider rail safety letter to Feds

Repost from The Benicia Herald
[Editor:  Original documents on the City of Benicia’s website:
      – Staff’s Agenda Report
      – Mayor Patterson’s draft letter of support
      – League of Cities letter requesting letters of support & sample letter]

City Council to mull rail safety missive

By Donna Beth Weilenman, April 2, 2015

Mayor Patterson seeks endorsement of letter calling for action to update federal policy on crude oil transport; no conflict seen with pending Valero request

Benicia, California

Mayor Elizabeth Patterson will ask the City Council on Tuesday to endorse a letter supporting the League of California Cities’ call for increased crude-by-rail safety measures.

Christopher McKenzie, the LCC’s executive director, already has sent a letter March 6 on behalf of its board of directors to U.S. Secretary of Transportation Anthony R. Foxx, asking that his department make LCC’s recommendations part of federal policy in governing rail safety.

“The continued increase in the transport of crude oil by rail, combined with recent rail rail accidents involving oil spills and resulting fires, have served to heighten concerns about rail safety among many of our member cities,” McKenzie wrote.

Rail safety, particularly in transport of crude oil from North Dakota’s Bakken fields, has become a growing concern nationwide and elsewhere.

The California Environmental Protection Agency has been presenting a series of forums on the matter, one of which took place March 26 in Crockett, a meeting attended by several Benicia residents who oppose delivery of oil by train.

In another development this week, WesPac Midstream has dropped the crude-by-rail component of its intent to transform a Pacific Gas and Electric tank farm into a regional oil storage site.

In explaining the move Project Manager Art Diefenbach cited uncertainties about prospective changes in regulations of oil shipping by rail, a series of protests and falling crude prices that have made shipping by train less attractive. Should the project be completed, oil would arrive either by ship or pipeline, which Pittsburg Mayor Pete Longmire suggested would make the operation safer and less controversial.

League-of-CA-Cities-LogoIn his letter, McKenzie cited incidents that prompted the LCC to express its own safety concerns and to offer recommendations that might reduce the potential for accidents.

“Specifically, two derailments accompanied by fires involving unit trains (100 or more tank cars) carrying crude oil in West Virginia and in Ontario, Canada, earlier this month have greatly increased public anxiety about what steps the relevant federal regulatory agencies are taking to improve rail safety and on what timetable,” he wrote.

He said the LCC wanted to make three points: First, that improvements that are required of participating industries should be mandates, not recommendations; second, that the mandates should have a hard deadline for implementation; and third, that the Department of Transportation should include the LCC’s recommendations in the final rule for Safe Transportation of Crude Oil and Flammable Materials.

McKenzie wrote that the LCC wants all federal agencies involved in regulating crude-by-rail shipments to require electronically controlled braking systems on trains carrying the sweeter crude from the North Dakota Bakken oil fields, and to set a sooner date for phasing out or retrofitting the older DOT-111 tanks.

More federal money should be directed toward training and equipment for first responders who are sent to hazardous materials accidents, he wrote, and how the funding is to be distributed needs to be defined. In addition, trains should have maximum speed limits in all areas.

His letter said the LCC wants the number of tank cars that trigger a California Energy Commission and State Emergency Response Commission report lowered to 20 from 33, which in turn would lower the trigger point from shipments of 1.1 million gallons or more to those of 690,000 gallons or more.

Priority routes for positive train control, a technology that incorporates geopositioning tracking to slow or halt trains automatically to reduce collisions, should be identified, McKenzie wrote, and parking and storage of tank cards need regulating, too.

He further wrote that railroads should be forced to comply with their Individual Voluntary Agreements with the US-DOT, because currently there is no requirement for them to do so. Those pacts involve reducing speed limits for oil trains that use older tank cars and travel through urban areas; determining the safest rail route; increased track inspection; adding enhanced braking systems; improving emergency response plans and training; increasing track inspections; and working with cities and communities to address their concerns about oil transport by train.

“The League of California Cities understands that this area of regulation is largely preempted by federal law,” McKenzie wrote. “That is why we are urging specific and timely action by the federal agencies charged with regulatory oversight in this area. We do not expect that derailments and accidents will cease altogether, but we anticipate that stricter safety standards will reduce their numbers over time.”

The LCC also has supplied member cities with a sample letter patterned after McKenzie’s message, to customize before sending to Foxx.

In a report to Benicia City Council, City Manager Brad Kilger wrote, “The League Executive Director has requested that cities send letters to the appropriate federal rail safety rulemaking authority requesting that these measures be implemented.”

Since the preparation of the letter template, he wrote, the LCC has learned that any decisions on improved safety regulations would be made in the Office of Management and Budget.

“The mayor is requesting that the city send a letter on behalf of the Benicia City Council,” Kilger wrote.

Consideration of the letter won’t conflict with future consideration of a request by Valero Benicia Refinery to extend Union Pacific Railroad tracks onto its property and make other modifications so it can substitute rail delivery for tanker ship delivery of crude oil, a highly contentious proposition that is currently undergoing environmental review.

“In that the city is currently processing the use permit and EIR (environmental Impact Report) for the Valero Crude-by-Rail Project, I asked the city attorney to determine whether sending a letter requesting rail safety improvements would in any way create a due process issue for the city,” Kilger wrote.

He said City Attorney Heather McLaughlin informed him there would be no conflict because the letter doesn’t take any position on the Valero project or the adequacy of the ongoing environmental review.

“The letter simply urges the adoption of more stringent federal standards for the transportation of crude by rail,” Kilger wrote.

If the Council agrees the letter should be sent to Foxx, it would be signed by Patterson as mayor, and copies would be sent to California’s two U.S. senators, Dianne Feinstein and Barbara Boxer, all members of California’s delegation in the U.S. House of Representatives, the Federal Railroad Administration, the National Transportation Safety Board, the Solano County Board of Supervisors, the Solano Transportation Authority, Kilger, McLaughlin and members of the Council.

The Council will meet at 7 p.m. Tuesday in the Council Chamber of City Hall, 250 East L St.

Western Cities Magazine: A Growing Risk – Oil Trains Raise Safety and Environmental Concerns

Repost from Western City Magazine

A Growing Risk: Oil Trains Raise Safety and Environmental Concerns

By Cory Golden, in the February 2015 issue of Western City
George Spade/Shutterstock.com
George Spade/Shutterstock.com

More and more often, trains snake down through California from its northern borders, with locomotives leading long lines of tank cars brimming with volatile crude oil.

Rail remains among the safest modes of transport, but the growing volume of crude being hauled to California refineries — coupled with televised images of fiery oil train accidents elsewhere — have ratcheted up the safety and environmental concerns of city officials and the residents they serve.

Local and state lawmakers have found that their hands are largely tied by federal laws and court rulings pre-empting new state and local regulation of rail traffic.

Growing Volume and an Increasing Number of Accidents

Until recently, California’s refineries were served almost entirely through ports. An oil boom in North Dakota and Canada from the Bakken shale formation and a lack of pipeline infrastructure have led to a dramatic increase in oil-by-rail shipments nationwide.

Oil imports to California by rail shot up 506 percent to 6.3 million barrels in 2013 (one barrel equals 42 gallons). That number will climb to 150 million barrels by 2016, according to the California Energy Commission.

The surge represents an “unanticipated, unacceptable risk posed to California,” said Paul King, deputy director for the California Public Utilities Commission’s Office of Oil Rail Safety, during a Senate hearing last year.

As the volume of oil being transported by rail has swelled, derailments in the United States and Canada have also increased. Despite $5 billion in industry spending on infrastructure and safety measures — with half of that for maintenance — railroads spilled more crude in the United States during 2013 than in the previous four decades combined, according to an analysis of federal data by McClatchy DC News.

Railroads continue to boast a better than 99 percent safety record, and most spills have been small, but with each tank car holding more than 25,000 gallons of oil, the exceptions — including eight mishaps in 2013 and early 2014 — have been dramatic and devastating, none more so than an accident in July 2013. That’s when 63 cars from a runaway train exploded, leveling much of Lac-Mégantic, Quebec, and killing 47 people.

So far, California has been spared a major crude oil accident, but the number of spills here is climbing: from 98 in 2010 to 182 in 2013, according to the California Office of Emergency Services (OES).

Trains carrying Bakken crude travel south through Northern California, turning from the western slope of the Sierra Nevada and rumbling through the hearts of cities large and small. The trains pass within blocks of the state Capitol, hospitals and schools and through sensitive ecological areas such as the Feather River Canyon and Suisun Marsh.

Lethal Accidents Spur a Push for Increased Safety Measures

The Lac-Mégantic accident and others that have followed have led to a push for change at the federal level. Two agencies of the U.S. Department of Transportation (DOT), the Federal Railroad Administration and Pipeline and Hazardous Materials Safety Administration, shoulder responsibility for writing and enforcing railroad safety regulations.

In early 2014, the DOT and railroad industry announced a series of voluntary steps to increase safety. The DOT released a comprehensive rule-making proposal in July 2014, calling for structurally stronger tank cars, new operating requirements, speed restrictions, enhanced braking controls and route risk assessments, and a classification and testing program for mined gases and liquids.

The DOT proposal calls for phasing out within two years older model tank cars, called DOT-111s, long known to be vulnerable to rupturing in a crash. The National Transportation Safety Board, which investigates accidents, first urged replacing or retrofitting them in 1991.

In September 2014, the American Petroleum Institute and Association of American Railroads jointly asked the DOT for more time — up to seven years to retrofit tank cars.

Another safety measure, called positive train control (PTC), makes use of global positioning systems. It is intended to prevent collisions, derailments due to high speeds and other movements that could cause accidents, like a train using track where maintenance is under way. PTC can alert train crews to danger and even stop a train remotely.

Following a 2008 Metrolink crash in Los Angeles that killed 25 people — caused when an engineer missed a stop signal and collided with a Union Pacific freight train — Congress mandated PTC implementation on 60,000 miles of track nationwide. Large railroads have spent $4.5 billion to implement the technology, but the industry says it cannot meet its 2015 deadline.

Among the members of California’s congressional delegation demanding stricter regulations are Senators Dianne Feinstein and Barbara Boxer, who have called for more information to be released to first responders on train movements.

Sen. Feinstein also wrote a letter that urged the DOT to include pneumatic brakes, which can greatly reduce stopping distances, in its planned review of tank car design, and to extend the PTC requirement to any route used by trains carrying flammable liquids near population centers or sensitive habitat.

Meanwhile, Industry Continues to Grow

The growth in domestic crude oil is reflected in projects that include seven proposed, completed or under-construction expansions that together would have a maximum oil-by-rail capacity of 561,000 barrels per day at Bakersfield, Benicia, Pittsburg, Santa Maria, Stockton and Desert Hot Springs (see “Increasing Refinery Capacity” below).

As of December 2014, the Kinder Morgan Inc. facility in Richmond was the only refinery that could receive unit trains, which are trains with 100 or more tank cars carrying a single commodity and bound for the same destination.

InterState Oil Co. had its permit to offload crude at McClellan Park, in Sacramento County, revoked in November 2014 by the Sacramento Metropolitan Air Quality Management District. The district said it had issued the permit in error and that it required a full review under the California Environmental Quality Act.

Refineries in Bakersfield, Vernon, Carson and Long Beach were receiving crude deliveries from manifest trains, which carry a mix of cargo.

Safety Efforts Focus on Planning, Preparedness and Response

The Federal Rail Safety Act of 1970 authorized the U.S. secretary of transportation to create uniform national safety regulations. States are allowed to adopt additional, compatible rules if they do not hinder interstate commerce and address a local safety hazard. Courts have consistently ruled against almost all attempts by states to use the local safety hazard exception, however.

Thus, unable to regulate train movements, California lawmakers and agencies have pursued three main courses of action: planning, preparedness and response.

In the Golden State, the California Public Utilities Commission (CPUC) shares authority with the federal government to enforce federal safety requirements, and OES and local agencies lead emergency response. In 2014, Gov. Jerry Brown expanded the Department of Fish and Wildlife’s Office of Spill Prevention and Response to include inland areas.

The Legislature approved a Senate Joint Resolution, SJR 27 (Padilla), urging the DOT to safeguard communities and habitat, strengthen the tank car fleet, mandate the earlier voluntary safety agreement with railroads and prioritize safety over cost effectiveness.

Recent legislation includes AB 380 (Dickinson, Chapter 533, Statutes of 2014), which calls for increased spill-response planning for state and local agencies and requires carriers to submit commodity flow data to OES, and SB 1064 (Hill, Chapter 557, Statutes of 2014), which seeks to improve accountability and transparency regarding CPUC’s responses to federal safety recommendations.

The FY 2014–15 state budget also allocated $10 million to the CPUC, which planned to add seven more track inspectors, and authorized the state oil spill prevention fund to be used for spills in inland areas. In addition, the budget expanded the 6.5 cent per-barrel fee to include all crude oil entering the state.

The 10 state agencies that have some hand in rail safety and accident response have formed the Interagency Rail Safety Working Group. It issued a report last June that called for, among other things, older tank cars to be removed from service, stronger cars, improved braking, PTC and better markings on cars so that firefighters know how to proceed in an accident.

Speaking to Richmond residents in December 2014, Gordon Schremp, senior fuels specialist for the California Energy Commission, welcomed the moves to increase safety at the federal level. All indications were that railroads were complying with new measures like lower speed limits, he said.

“Does it mean there will be zero derailments? No, but the goal is to get there,” said Schremp.

Local government officials face a daunting challenge when it comes to disaster response.

The Interagency Rail Safety Working Group also found that, as of June 2014, there were no hazardous materials response teams in rural areas of Northern California and units in other areas of the state lacked the training and equipment needed to take a lead role. Forty percent of the state’s firefighters are volunteers.

“Training is of the utmost importance,” said Deputy Chief Thomas Campbell, who oversees the Cal OES Hazardous Materials Programs. “We understand that local governments are limited in finances and that it’s difficult to get firefighters out of rural communities to train because they are volunteers.”

Some Local Communities Oppose Expansion

At the local level the proposed expansion of California refineries sometimes has run into heated opposition.

After news reports revealed that Bakken crude was being transported into the City of Richmond, City Manager Bill Lindsay wrote a letter to the Bay Area Air Quality Management District in November 2014 calling for it to revoke energy company Kinder Morgan’s permit to offload the crude there. That followed a lawsuit filed by environmental groups to revoke the permit — a suit tossed out by the judge because it was filed too late.

Elsewhere, a proposal by Valero Energy Corp. would bring 1.4 million gallons of crude daily to its Benicia refinery. The proposal has been met with letters questioning the city’s environmental and safety analysis from senders that have included the CPUC, Office of Spill Prevention and Response, the Sacramento Area Council of Governments, the Capitol Corridor Joint Powers Authority and cities along the rail line, including Davis and Sacramento. The Union Pacific Railroad has responded by stressing federal pre-emption of rail traffic.

Even as those proposals played out, a pair of derailments in Northern California underscored the importance of the debate. While neither spill involved crude oil or hazardous materials, both served as a warning of the need for California to improve its emergency response capability. Eleven cars carrying freight derailed and spilled into the Feather River Canyon near Belden on Nov. 25, 2014. Three days later, one car tumbled off the tracks near Richmond. The cars were loaded with corn in the first instance and refrigerated pork in the second.

What’s Ahead

The League continues to closely monitor developments in oil by rail. In September 2014 the League made recommendations to the DOT on the federal rule-making governing rail safety. The recommendations included providing more information and training to first responders, mandating speed limits and stronger tank cars, and using all available data to assess the risks and consequences of crude oil transport. Two months later, the National League of Cities passed a resolution stressing many of the same safety measures.

League of California Cities staff conducted a series of webinars during fall 2014 to better acquaint members with the oil-by-rail issue, and its Public Safety and Transportation policy committees took up the subject in January 2015 meetings.


Increasing Refinery Capacity

The California Energy Commission is tracking the following projects, which would dramatically increase the oil-by-rail capacity of refineries:

  • Plains All American Pipeline LP in Bakersfield, which took its first delivery in November 2014, has a capacity of 65,000 barrels per day (bpd);
  • Alon USA Energy Inc. in Bakersfield, under construction, will be able to receive 150,000 bpd;
  • Valero Energy Corp. in Benicia, which is presently undergoing permit review, would have a 70,000 bpd capacity;
  • WesPac Energy-Pittsburg LLC in Pittsburg, undergoing permit review, could receive up 50,000 bpd by rail and 192,000 bpd through its marine terminal; and
  • Phillips 66 in Santa Maria, undergoing permit review, could accept 41,000 bpd.

In addition, Targa Resources Corp. at the Port of Stockton is planning an expansion that would enable it to receive 65,000 bpd. And Questar Gas Corp. is planning a project that could see it offload 120,000 bpd near Desert Hot Springs, then send it through a repurposed 96-mile pipeline to Los Angeles.


Photo credits: Ksb/Shutterstock.com; Steven Frame/Shutterstock.com.

 

BENICIA HERALD LETTER TO THE EDITOR: Dr. James Egan: Deny Valero’s application

From The Benicia Herald (Benicia Herald letters appear only in the print edition)
[Editor:  Dr. Egan’s letter is a welcome contribution, expressing the growing conviction of many throughout North America, that crude-by-rail is simply unsafe under current conditions, and should be not be permitted at this time.  See also Dr. Egan’s 9/14/14 comments addressing the Valero Crude By Rail Draft EIR.  – RS]

Timely decision on crude by rail warranted: Deny Valero’s application

By James Egan, M.D., Benicia, March 10, 2015

The headline in the Feb. 5, 2015 edition of The Herald, “Another delay as crude-by-rail project debate enters 3rd year,” signals sympathy toward the Valero Benicia Refinery as regards its Crude by Rail (CBR) Use Permit Application, currently before the Planning Commission.  While it is difficult working up crocodile tears for a multi-billion-dollar international oil corporation, the energy and expense invested in forwarding this project bear acknowledgement, and a timely decision on the application should be made out of fairness to the applicant.  To that end, I would like to suggest that the Planning Commission and the City Council have enough information available to take action at any time.  The application should be denied on the basis of rail safety.

On Feb. 17 of this year a crude oil train derailed and exploded in Mount Carbon, W.Va.  Three million gallons of Bakken crude spilled from 26 ruptured tank cars, forcing the evacuation of two nearby towns.  Two days prior, another oil train derailed and caught fire in Ontario, Canada.  Last Thursday, March 5, 21 cars carrying Bakken crude derailed, split and exploded near Galena, Ill.  Another of the dozens of oil- or ethanol-train accidents involving a fire, derailment or significant fuel spill reported in the U.S. or Canada since 2006 was the Lynchburg, Va. derailment and fire in April 2014.

The significance of this particular series of railway disasters to the citizens of Benicia is that they all involved CPC-1232 tank cars, the same cars that Valero would use for the transportation of crude to its facility in Benicia, according to the Draft Environmental Impact Report.

In a Feb. 23 editorial titled, “Get rid of exploding tank cars,” the San Francisco Chronicle states that “Valero Energy Co. has agreed to haul Bakken crude to its Benicia bayside refinery in the newer CPC-1232 cars as part of its city permit application to revamp its facilities to receive crude by rail rather than by oceangoing tanker.  But that promise now appears inadequate to protect the safety of those in Benicia as well as in other communities – Roseville, Sacramento, Davis – along the line.”

The same edition of the Chronicle details a report from the Department of Transportation predicting that trains hauling crude oil or ethanol will derail 15 times in 2015 and average 10 times yearly over the next two decades, causing $4.5 billion in damage with potential fatalities of more than 200 people in a given accident.  This may actually be an underestimate based on recent major derailment rates.

Friends and foes of CBR alike agree that the transportation of crude oil by rail involves inherent risk.  Can’t we also agree that the risk should be reduced to the greatest extent possible before inviting these potentially explosive trains to Benicia?  Lowering the risk of tank car derailment, rupture and explosion now should translate into saved human lives and prevention of environmental disasters in the future.

The danger can, in fact, be mitigated.  The crude can be stabilized prior to its transportation by extraction of its most volatile components.  North Dakota has implemented standards making this mandatory for Bakken crude, but many feel that their new guidelines are overly lax.  New federal regulations due to be released in May could further address this, as would rail safety measures such as Positive Train Control and electronically controlled pneumatic brakes.  New, safer tank cars designed specifically to carry this type of crude have been designed and are in production.

Unfortunately, the new federal guidelines will likely require years for full enforcement, and complete phaseout of the existing, unreliable tank car fleet by newer, stronger cars, such as the Greenbrier HM-251, will also require years of effort.

Accordingly, if we agree that the risks of transportation of crude by rail should be absolutely minimized prior to approving the CRB project, we have to acknowledge that this is currently beyond Valero’s reach and the Use Permit Application should be denied.

Those who would roll the dice and approve the current application should consider how comfortable they will feel with that decision once they find themselves in a front row seat at the Park/Bayshore railroad crossing watching fifty tank cars containing 1,470,000 gallons of potentially explosive crude rumble by on the same spur line that has seen derailment of five train cars since Nov. 4, 2013 (in addition to the two locomotives that derailed on Sept. 7, 2014 near the port).

Kudos to Planning Commission members for the time and energy spent on fairly evaluating this project.  It would seem that as time has passed the correct path forward has become much clearer.  At this point, the ongoing health and well-being of all Benicians should hold foremost importance in the decision-making process.  Their protection is the least we can expect from our city government.

James Egan, M.D.

U.S. oil train rule changes would have side effects on passenger, freight traffic

Repost from The Democrat & Chronicle, Rochester, NY

U.S. oil train rule changes would have side effects

By Brian Tumulty, January 13, 2015
Railroad oil tanker cars parked at the Port of Albany. Each week between 20 and 35 freight trains pulling such tankers roll through Monroe Coundy. (Photo: Mike Groll / AP file photo 2014)

WASHINGTON – Long-distance passenger and freight rail service could be headed for gridlock later this year if trains hauling crude oil and ethanol are limited to 40 miles per hour.

And it could get worse. If the controversial Keystone XL pipeline doesn’t win approval, the American Petroleum Institute estimates “an additional 700,000 barrels per day” will need to be shipped by freight rail. That would require an additional 1,000 rail tank cars every day to transport the tar sands oil the pipeline was intended to carry from Canada to the U.S.

Passengers in the tens of thousands per year travel on trains that stop in Rochester and could potentially be affected by the decisions that will soon be made.

The speed limit, proposed by federal regulators, would cause “severe disruption of freight and passenger rail service across the U.S.,” according to the National Shippers Strategic Transportation Council, a trade group.

The result of the debate will affect both local passengers who use Amtrak — 145,000 people boarded or got off at the Rochester Amtrak station in 2013 — and local activists worried about potential safety issues involving the oil tanker trains that run through Monroe County. Between 20 and 35 oil trains roll across upstate each week, passing through Monroe County on their way to Albany.

The Association of American Railroad says the 40 mph speed limit, and a related proposal requiring freight trains carrying crude oil or ethanol to have electronically controlled pneumatic brakes, “would have a devastating impact on the railroads’ ability to provide their customers with efficient rail transportation.”

Amtrak, which carried 31 million passengers overall in 2013, runs most of its trains on tracks owned by the nation’s major freight railroads. Trains on the Albany-Syracuse-Rochester-Buffalo corridor use a pair of tracks owned by Florida-based CSX Transportation.

Under federal law, freight railroads are required to give priority to Amtrak as they dispatch trains on their systems. But the system has always been imperfect, and scheduling conflicts with freight trains, along with numerous other problems, have made delays a fact of life on most Amtrak routes.

Amtrak supports imposing the 40 mph speed limit only in federally defined “high-threat urban areas” where the risk of a catastrophe is considered greatest. There are just over 50 around the country, including the New York City metro area and Buffalo.

“Anything more restrictive, if it affected network fluidity, could have adverse effects on Amtrak,” the railroad wrote.

The challenge for the oil and gas industry is continuing to safely transport crude oil from new oil fields to refineries.

About 70 percent of crude oil produced in the Bakken Shale Formation of North Dakota and Montana is shipped by rail, according to the oil refineries trade organization.

And production is continuing to increase, from less than 200,000 barrels per day in 2008 to nearly 1.2 million barrels per day in 2014, according to the American Petroleum Institute. Freight railroads predict production eventually will reach 2 million barrels a day.

About 70 percent of ethanol also is transported by rail.

Meanwhile, the nation’s rail network is operating at near capacity. Last year, its choke points resulted in a dramatic drop in the on-time performance of many long-distance Amtrak passenger trains.

Amtrak’s Capitol Limited route between Chicago and Washington had an on-time performance of less than 3 percent in the three months ending Sept. 30. Amtrak provided bus service between Chicago and Toledo, Ohio, for six days in October because some trains were running 10 hours late.

Freight rail shipments from grain elevators faced delays of up to three months a year ago. Freight railroads weren’t prepared for harsh winter weather on top of increased crude oil shipments.

Freight railroads say they’re spending billions of dollars to improve capacity — they largely avoided delays in shipping farm commodities following this year’s harvest — but a 40 mph speed limit for oil trains could undermine that.

“The impact on railroad capacity can be compared to traveling on a two-lane highway,” the Association of American Railroads said. “Slowing down one car or truck affects trailing vehicles. Similarly, slowing down one train affects trailing movements, except that the impact on railroad traffic is much worse because the opportunities to pass are much more constrained than on a highway.”

Trains can pass only at widely spaced locations on a railroad, whether single or double-tracked. Research on rail capacity has shown, and rail operators have long understood, that reducing speeds reduces network capacity.”

At issue is safety in the wake of several derailments of oil trains. The most notable, in the Quebec community of Lac-Mégantic in July 2013, killed 47 people.

Many rail industry groups and shippers say federal efforts to improve the safety of “unit” trains carrying at least 100 tankers loaded with crude oil should focus on fixing faulty tracks. New speed reductions, they say, should be limited to the most densely populated areas.

The National Transportation Safety Board lists improvements in rail tanker car safety as one of its 10 most wanted safety improvements for 2015. It also lists installation of “positive train controls,” which automatically slow trains going into a curve if the operator doesn’t.

“The NTSB does not have a specific position on any specific speed limits but what we do want to make sure first of all is, does the train stay on the track,” said Robert Sumwalt, a member of the NTSB board. “And PTC (positive train controls) is one good way of ensuring that the trains stay on the track. We want to make sure if they do derail, there’s adequate protection in the tank cars. And finally if the tank cars breach, we want to make sure there’s adequate emergency response.”

Federal officials late last year received more than 3,400 public comments on an array of proposals aimed at safer transportation of crude oil by rail. They include a new design for tank cars, retrofitting existing tank cars, installing new braking systems and speed restrictions.

Three possible speed-limit scenarios been proposed — one would limit oil trains to 40 mph at all times. Another would impose the 40 mph limit only when trains pass through regions of at least 100,000 people, and another would impose it only in cities defined as high-threat urban areas.

Trains using a new generation of safer tank cars would be allowed to travel at 50 mph.

The proposed speed limit would apply to “high-hazard flammable trains,” which federal transportation officials would define as any train carrying at least 20 tankers loaded with crude oil or ethanol.

Railroads say 20 cars is too few because freight trains add and subtract cars as they move along the nation’s vast rail network.

The average unit train has 94 tank cars, according to the American Fuel & Petrochemical Manufacturers association, which represents the owners of 120 refineries.