OMAHA, Neb. - Opponents of a proposed pipeline designed to carry crude oil from Canada under the Great Plains filed a lawsuit Wednesday challenging Nebraska's new oil pipeline review law.

The lawsuit was filed directly with the state Supreme Court. In it, several Nebraska landowners along TransCanada's proposed pipeline route claim the law establishing the review process is unconstitutional because it doesn't allow for judicial review and doesn't spell out what criteria should be considered when a proposed pipeline is being evaluated.

The Nebraska Attorney General's office declined to comment on the lawsuit Wednesday because it had not received a copy of it.

The lawsuit also objects to putting the Nebraska Department of Environmental Quality in charge of reviewing the pipeline project instead of the state's Public Service Commission, an independently elected group that regulates utilities.

The landowners who filed the lawsuit say they're concerned about the provisions of the law that could allow a pipeline company to use eminent domain to obtain land for a project.

"I believe very strongly in our rights as Nebraska citizens. All of us take it extremely personally when we are threatened with eminent domain," landowner Suz Luebbe said in a statement.

The lawsuit also argues that the bill is unconstitutional special legislation because it can only be applied to TransCanada's Keystone XL project.

TransCanada's proposed Keystone XL pipeline is designed to carry oil from Canada across Montana, South Dakota, Nebraska, Kansas, Oklahoma and Texas. TransCanada also has proposed connecting it to the Bakken oil field in Montana and North Dakota.

Environmental groups have opposed the project because of concerns that the pipeline could foul underground and surface water supplies, increase air pollution around refineries and harm wildlife.

TransCanada's original application for a federal permit to build the pipeline was rejected in January by President Barack Obama after congressional Republicans imposed a deadline for approval that didn't allow enough time to address questions about the route through Nebraska.

Since then, TransCanada has split the project into two pieces. The company hopes to quickly get approval for the southern section of the pipeline between Oklahoma and the Gulf Coast. And TransCanada has proposed a new route through Nebraska that avoids the environmentally sensitive Sandhills region.

Nebraska officials held public hearings on the new proposed pipeline route earlier this month. The state's review process for the new route is expected to be completed in late summer or fall.