MnDOT: Highway 53 re-route on the Iron Range needs more time
Roberta Dwyer says she gets criticized for using “unique” far too often to describe the proposed U.S. Highway 53 re-route in Virginia, but she just can’t come up with a better word.
The project engineer for the Minnesota Department of Transportation says there’s never been anything like the plan to build a four-lane expressway across an abandoned open-pit mine, either by filling in part of the pit to build a road or by building a 2,800-foot-long, 325-foot-high bridge across the chasm.
Engineers have called it the most geologically challenging highway project they have ever worked on.
The exact re-route of the highway still hasn’t been picked and will in large part be determined by a $4 million project this summer to drill test borings and build test foundations for the possible bridge across the water-filled Rouchleau Pit on the southeast side of Virginia.
“We aren’t going to get a route until we get these tests completed and analyzed,” Dwyer told the News Tribune. “These tests are going to go a long way in determine the future of this project.”
And MnDOT officials announced Wednesday that, even if a preferred route is picked later this year, they almost certainly won’t meet the May 2017 deadline to have the new highway completed.
Once a final route is picked the state still must conduct a full-scale environmental impact statement. And construction itself probably will take much longer than a year.
“It’s a very, very complicated project from an engineering standpoint … and we’re saying it’s going to be very difficult now to meet that deadline,’’ said Kevin Gutknecht, MnDOT communications director.
The highway has to be re-routed because of a codicil in the 1960 deal between owners of the mineral rights under the highway and the state. The deal allowed the state to build the highway, but also gave the owners the right to kick the highway off with seven years’ advance notice.
They did just that in 2010, with Cliffs Natural Resources and holders of the mineral rights saying it wants to expand the Thunderbird Mine that provides taconite iron ore for Cliffs’ United Taconite operations. If the taconite plant is to remain open, Cliffs says, it needs access to the ore that now lies beneath the highway. That notice set the clock running to May 1, 2017.
Cliffs spokeswoman Sandy Karnowski said news of the possible delay was disappointing.
“We are disappointed in the delay and are hopeful that MnDOT can address any challenges associated with this project in the near term so the highway realignment timeline can remain on track,” Karnowski said. “Timely completion of the realignment is needed to prevent undue interference with mining activity or traffic through the highway corridor.”
EXTENSIVE, EXPENSIVE TESTING
Dwyer said tests this summer will tell engineers what options are possible and affordable, and eliminate some that are not. Then the environmental impact statement must be completed on the preferred route choice for the region’s most important north-south commerce corridor that carries up to 23,500 vehicles per day.
The problem is that the bottom of the pit, under the water, is neither uniform nor stable, Dwyer said. Tests have shown that the bottom was back-filled with mine waste — rocks that vary from “the size of Volkswagens to small pebbles.” That rubble ranges from 40 to 140 feet thick, Dwyer said.
It may be the most expensive pre-construction testing ever done in the region. And it’s strong indication that the actual highway project is likely to cost far more than the $90 million currently earmarked. Exactly how much more “depends on what we find out this summer,” Dwyer said.
One of the options calls for a bridge over the Rouchleau Pit that is as far off the bottom of the mine pit as the Blatnik Bridge in Duluth is above St. Louis Bay. The pit walls are up to 325 feet high in places; the pit lake that has formed with groundwater seepage and rainfall is 250 feet deep in some spots.
MnDOT officials updated local residents and officials at Wednesday’s meeting of MnDOT’s Highway 53 Relocation Public Advisory Committee held at the Mountain Iron Community Center. Another public update is set for 10 a.m. today at the Virginia MnDOT building.
Officially, only one option has been discarded — to re-route the highway west of Eveleth and Virginia and back to its current alignment in Mountain Iron. Business owners along the existing highway protested loudly, and politicians were successful in getting the option killed early in the process.
Several other options remain:
* No build. Essentially close the highway; that’s not likely to happen.
* No new building. Instead, the state would try to “buy out” the rights to the iron ore below the highway, a prospect that could cost hundreds of millions of dollars and which mining officials say could close the entire United Taconite operation when it runs out of ore, putting hundreds of people out of work.
“If United Taconite does not mine the ore body under the current highway, it would reduce the life of mine, which would also limit the positive, long-term employment and economic benefits of the operation for the surrounding communities,” said Sandi Karnowski, Cliffs spokeswoman in Duluth.
* The so-called M1 option to build the new road just west of the current alignment, right through the heart of the existing Thunderbird Mine operation’s Auburn Pit. Cliffs has said it won’t allow that option because of too many technical and regulatory hurdles and because it may hinder mine access. MnDOT still is studying the option, however, and conducting tests.
The most likely options include:
* The E1A bridge option, the most direct but potentially challenging route over the Rouchleau Pit and linking back with the existing highway alignment at about the Virginia Target store.
* The E1A fill option, which would fill in part of the open-pit mine, following along an old road used to move ore out of the mine and routing the new highway on fill rather than a bridge. A sub-option has the fill encased in concrete, looking much like a dam.
* The E2 option to cross the same mine pit but much farther north, taking a longer loop to meet back up with the existing highway alignment, still near the Target store.
The E1A options appear to be the most appealing, and acceptable to Cliffs, local businesses and local officials. But MnDOT engineers need to know if the rubble at the bottom of the mine pit is stable enough to hold massive bridge foundations, as big as eight feet in diameter, Dwyer said.
Idea Drilling has had a barge on the lake that now fills the Rouchleau Pit, with crews testing core samples inside the pit. Another barge and drill rig will be on the lake next week. The state contract for the test bridge foundation will be let July 26 and work is scheduled to start Aug. 11.
Dwyer said she expects results by September, followed by some sort of paring-down of options if not an actual preferred route picked by MnDOT.
State officials say that funding for the final route picked is not likely to be an issue, even if the final project is a budget-buster. State lawmakers this year approved an extra $19.5 million from the state’s construction bonding bill to pay for the re-routing of utilities — sewer, water and electric lines — that follow Highway 53, costs that otherwise may have been covered by local residents’ property taxes. That money will also pay to move the Mesabi Trail recreation trail.