Union Pacific's theme this year is "Building America for 150 years," marking President Abraham Lincoln's signing of the Pacific Railway Act and creation of the company in 1862.

Evidence of this iconic company's role in building the nation was on display in Old Sacramento this past weekend – from the last steam locomotive built for Union Pacific (No. 844) to the latest advanced, experimental, low-emissions locomotive (No. 9900).

But part of that legacy involves the UP merger with Southern Pacific and a 130-year history of building and repairing trains in the Central Shops in the downtown railyard – leaving behind oil, fuel, caustic cleaning solutions, paint, gas solvents and thinners, chlorinated solvents, acids and metal alloys.

UP has been the named "responsible party" for cleanup since the 1980s, yet getting agreement on details has remained elusive. Ray Leclerc, deputy director of the California Department of Toxic Substances Control, has said the parties are "90 percent there" on a "remedial action plan" for the Central Shops and South Plume areas.

The bottom line is that UP has to accept responsibility for a level of cleanup that allows people to live in the railyard – with trees and grass and without children eating contaminated dirt.

Leclerc believes a final agreement will be in hand by the end of the year.

We hope he's right. Until details are settled, development plans for the 244-acre Sacramento railyard are stuck in limbo.

In the meantime, federal and state grants have deadlines. The city took a risk and moved ahead with excavation for track relocation, a project completed in August that ended old conflicts between 28 freight trains and 42 passenger trains each day. In the process of digging, a container of soil and a tank turned up – a cleanup cost the city bore upfront and will now have to try to recover from UP.

UP was a direct beneficiary of that project. Where freight trains used to have to slow to 10 miles per hour or stop in Sacramento, now they can zip through at 30-35 mph. Minutes mean big money in the highly competitive freight market.

A remediation plan should make it clear that UP is responsible for surprises that turn up in the future.

In the Central Shops, $16 million in federal and state grants must be spent by 2014-15 to stabilize and renovate the Boiler Shop and Erecting Shop, so private fundraising can proceed for a planned Rail Technology Museum. The land title transfer has been pushed back multiple times because of cleanup issues.

The issues in the buildings are not that complex – nobody's going to be digging up floors. The parties can agree that as leaky windows, doors and roofs get fixed, UP will be responsible for the cost of a vapor mitigation system.

Only with agreement on cleanup can a land transfer take place.

A remaining contentious issue is whether UP should be responsible for a level of cleanup that would allow for ground-floor housing in land surrounding the Central Shops. The city and property owner, Inland American, say yes; UP says no.

The city's 2007 Specific Plan is clear that the area is a Residential/Commercial Mixed Use Zone, emphasizing "commercial uses with a residential component."

Cleanup levels for vapors in residential and commercial areas are the same, so that's not an issue; the parties agree on UP's responsibility for vapor mitigation.

The concern is for children, and their potential exposure in the future to toxic dirt with ground-floor housing. To make housing safe means bringing in clean soil or doing "hardscape" landscaping. Unfortunately, UP's position is to reject ground-floor residential as a change in the "planned use of this property which has been in place for more than 20 years."

This is unacceptable.

No one wants to take on property without a clear path on who will be responsible for cleanup measures, whether it's for the Central Shops buildings or other parcels.

In this 150th anniversary year, UP has much to celebrate, including record profits and record stock prices.

A capstone would be a clear message that UP will shoulder its responsibility to clean up the toxic legacy in Sacramento's downtown railyard – so land transfers and work can begin on a livable community.

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