A bid by railroad titan Union Pacific Corp. to double the capacity of its main rail yard near the ports is running into resistance from environmental and health groups, and the community.

The Natural Resources Defense Council along with Communities for Clean Ports, the American Lung Association and 10 other groups is demanding a major cut in diesel emissions at the yard before the project is started.

The face-off is threatening to become a repeat of the TraPac controversy in which the NRDC and its allies halted the expansion of a Los Angeles port terminal. The impasse was broken when the port agreed to spend $50 million to reduce the environmental impact of future expansions within the port.

The railroad wants to expand the cargo-handling capacity of its 233-acre Intermodal Container Transfer Facility where containers trucked from the ports are transferred to trains for distribution across the nation.

Currently, the yard is capable of handling 725,000 containers annually. The railroad wants to increase the capacity to 1.5 million containers, citing estimates that port import and export traffic will likely triple in the coming decades.

The two ports’ Joint Powers Authority recently gave Union Pacific a green light to prepare initial documents for the project. The company hopes to begin construction within another year or two.

The ports said at a recent meeting that they could give roughly $8 million to help fund a clean up of the rail yard before expansion work begins, but the opponents say the figure is too small. And the railroad has yet to say whether it will match the funds, as the groups contend is necessary.

However, the opponents say that the railroad should first make a variety of improvements over the next 18 months to reduce diesel pollution before any expansion. Among the requests are a switch to hybrid locomotives and the installation of particulate filters on switching locomotives that do much of the work at the yard.

Moreover, the groups are suggesting that the railroad help develop and deploy zero emission, all-electric drayage trucks which carry the containers from the ports to the yard. That move would go a step beyond the ports’ recently passed $2.2 billion clean truck program, which over several years will replace all 16,000 short haul diesel trucks with clean diesel, electric and other alternative powered trucks.

“UP should work to clean up existing rail yard pollution in the South Coast before expanding operations within the basin,” the group said in a letter that was sent to the railroad, ports and state and regional air quality regulators last week.

So far, Union Pacific has rebuffed the groups and is working to assemble the preliminary documents necessary to move forward with its expansion project at the yard, which opened in 1986.

Zoe Richmond, a Union Pacific spokeswoman, said the company acknowledges that much of its equipment is outdated, but maintains that some of the requests are unrealistic, such as its request to help develop and deploy electric trucks.

“The electric truck issue is something that is beyond our control,” said Richmond. “We are looking at some of the concerns and seeing where we can find some common ground. When it comes to green technology, we are trying to adopt it as soon as possible.”

David Pettit, a senior attorney with the NRDC, said the group will be closely watching the railroad’s formal response to its demands, and doesn’t plan to walk away if they are not met.

“There’s a huge amount of community opposition to the ICTF expansion,” said Pettit. “It’s in UP’s interest to appear to be a good corporate citizen if it wants to get this project through. There’s a number of legal hooks (to challenge the project.)”

The NRDC was able to slow up the expansion of the terminal operated by TraPac Inc. by appealing the Port of Los Angeles’ approval of the project to the City Council, where it lobbied hard against the project.

Ultimately in exchange for the $50 million environmental remediation fund TraPac was given approval to pursue its $1.5 billion project, which will triple the capacity of its terminal.

To support its latest effort, the NRDC enlisted Andrea Hricko of the University of Southern California’s Keck School of Medicine to assess the environmental impact of operations at the transfer facility.

In a report Hricko released recently she stated that the rail yard already poses a health risk to the surrounding community and that it only would get worse after an expansion.

“Exposure to diesel (particulate matter) emissions related to current operation of the (rail yard) creates a serious public health risk to nearby residents and school children,” Hricko said in the report. “Mitigation measures to reduce the risk should be undertaken immediately to protect the health of nearby populations.”