In December, the Nebraska DEQ issued a map showing the regions that the pipeline must avoid. It used the same Sandhills boundaries as a 2001 map called Ecoregions of Nebraska and Kansas.

"I think if you're protecting the ecological aspects of the Sandhills, the boundary we have is probably better than any of the other [available maps]," James Omernik, a retired EPA scientist and a principal author of the ecoregions map, told InsideClimate News last month. "If you are more concerned about the water table or sandy [soil] or any other characteristic, then you might want to build a buffer around the Sandhills that would include the characteristic you're trying to protect."

Goeke said the landowners have some valid concerns. The new route still crosses "areas with high water tables, but [it's] a lot less than the original route," he said.

Citing TransCanada's route-proposal document, Goeke said the preferred corridor would cross 10.5 miles where the groundwater lies 5 to 10 feet below the land surface, equal to "a little over six percent of the entire route through Nebraska."

Another 12.4 miles would cross where depth to water is 10 to 15 feet. The same document says the new route would not cross any regions where depth to water is between zero and five feet.

That calculation seems to ignore numerous river and stream crossings where the water lies close to the ground. Goeke speculated that TransCanada might have excluded the rivers because the company plans to bury the pipeline beneath rivers at the crossings.

InsideClimate News contacted TransCanada for comment, but the company didn't respond before deadline.

DEQ to Review Route

Now that TransCanada has chosen its preferred corridor, it's up to the DEQ to analyze the route for environmental impacts. DEQ spokesman Brian McManus said the agency will schedule informational meetings and distribute detailed maps that identify properties that could be impacted by the proposed route.

"And at that point, after we have our initial discussions with the public, and do some initial review, we're going to provide some feedback to TransCanada," McManus said. "Then is when it really gets into the detailed review process. TransCanada would finalize the route and submit it to the state for evaluation."

McManus said he could not comment on the technical aspects of the environmental review. He directed InsideClimate News to DEQ director Mike Linder, but Linder was not available to comment before deadline.

Pipeline opponents are wary of the DEQ process because they say it is less rigorous and less transparent than the review guidelines being drafted by the Public Service Commission. A bill that passed in November placed the PSC in charge of the Keystone XL review, but another bill called LB 1161, signed into law last week, gave DEQ control of the project.

Any route approved by the DEQ will be given to the governor for evaluation. Gov. Heineman has repeatedly expressed his support for the pipeline. While signing LB 1161 into law, he issued a statement that "Nebraska will move forward on the review process of the proposed Keystone XL pipeline and any future pipelines that will create jobs and reduce U.S. dependence on Middle Eastern oil."