Jeff Rauh and Wayne Woldt reached out to very different audiences Tuesday with their thoughts on the proposed Keystone XL pipeline.

Rauh, spokesman for pipeline builder TransCanada, promoted the project to about 175 members of the Downtown Rotary Club in Lincoln and suggested that many of its critics want to do more than move it away from the Nebraska Sandhills and the Ogallala Aquifer.

"These groups are working to stop the project," Rauh said.

Meanwhile, Woldt, a groundwater engineer at the University of Nebraska-Lincoln, elaborated on a letter he and fellow UNL faculty member and hydro-geologist John Gates sent earlier this month to the U.S. State Department calling for a more thorough investigation of the potential for groundwater contamination.

"I'm not really commenting on the route selected, that determination," Woldt said in an interview, "but rather more from a scientific point of view of how do we prepare for the eventuality (of a spill) should it occur."

The proposed $7 billion pipeline connection between the oil sands of Alberta and refineries along the U.S. Gulf Coast remains under review by the State Department. Separate actions on an environmental impact statement and in determining if the project is in the national interest are expected by the end of the year.

It remains controversial with landowners along the route and with Bold Nebraska and other in-state groups worried about soil erosion and spills in areas of porous soil and high water tables.

But if Rauh was concerned about tough questions in front of an attentive audience, that possibility disappeared with program preliminaries and with him wrapping up just in time for the prompt 1 p.m. adjournment of the civic group.

Up to that point, he was able to call attention to Canada's status as the second leading repository for untapped petroleum resources in an insecure energy world and to downplay a series of what he described as "releases" at pump stations on TransCanada's first Keystone pipeline that required clean-up action.

The first pipe passes west of Seward. Easily the biggest spill, of some several hundred barrels, was in south-central North Dakota.

"Nothing about these events causes any questions about the integrity of the pipeline itself," Rauh said.

Furthermore, "the fact of the matter is that the U.S. is filled with aquifers ... so we can't avoid them all."

The letter UNL faculty members Woldt and Gates sent to the State Department carried a different tone and came at the end of the latest public comment period on the environmental impact of Keystone XL.

Much of the letter's emphasis was on the dearth of public research of the effects of an oil spill in an aquifer setting and especially in a setting where "lakes and streams in the Sandhills are fed almost exclusively by groundwater."

A study detailed enough and specific enough to determine the risk of an oil spill in the Sandhills would take some time, Gates said in a follow-up interview.

"I don't think that it would be years, (but it) depends on a lot of factors having to do with personnel, also data availability."

TransCanada officials have pointed out repeatedly the project already has been immersed in the review and permitting process for three years.

As the public comment period closed June 6, the Environmental Protection Agency raised its own concerns about what its scientists saw as insufficiencies in the State Department approach.

"I have not read the EPA's comments thoroughly," Gates said. "My understanding is that there was general disapproval of the degree of specificity, and we would tend to agree with that."

Woldt cited "some degree of synergy between what they're saying (at EPA) and what John and I are saying in relation to science, what we know about the potential for this type of contamination event and what we don't know."

A study in Nebraska could better match research to the Keystone XL situation.

"We understand risk in a general sense," Gates said, "but a project of this magnitude -- we're advocating that we quantify risks in a much more specific way."

That could put more facts in State Department hands before the pipeline is built.

"I think it puts them in a much better position. It also puts Nebraskans in better position to assess their risk."

If the project goes forward, a Sandhills-based analysis also could "better inform remedial strategies and clean-up plans."

Reach Art Hovey at 402-473-7223 or at ahovey@journalstar.com