SERGEANT BLUFF | Two dozen cranes tower over the juxtaposition of steel and concrete rising out of the ground.
The largest crane, nicknamed "Big Boy," can lift as much as 1,000 tons, with a boom that extends up to 350 feet into the air.
Such power and reach have been put to the test as a legion of workers erect CF Industries' sprawling new fertilizer plant at Port Neal.
As the mega project enters its second full year, a series of structures with mind-boggling dimensions are in various stages of construction, such as:
-- A 93-foot-tall primary reformer with a base measuring 61-by-48 feet. The primary reformer and its neighbor, a secondary reformer at a height of 44 feet, are among the pieces of equipment that will be used to make anhydrous ammonia, a building block for nitrogen-based fertilizer.
-- Twin storage tanks that are each 155 feet in diameter and 106 feet to the top of the roof. When finished, each tank will hold about 30,000 tons of ammonia.
-- A warehouse that's 210 feet wide and 1,702 feet long, or nearly a third of a mile. One of the largest in North America, it will store up to 154,000 tons of granular urea, a solid nitrogen fertilizer that has not been produced at Port Neal in two decades.
The massive project includes construction of a 3,850 tons-per-day urea synthesis and granulation plant, and a 2,420-tons-per-day ammonia plant. The latter will triple the Port Neal complex's daily production of the chemical to about 3,500 tons.
Nearly everything about the expansion is enormous, starting with the price tag, which recently hit $2 billion, about $300 million more than originally budgeted.
When the expansion was announced in November 2012, it was the largest economic development investment in Iowa history.
After the design was finalized, costs for labor, materials and winterizing the plant against the often harsh conditions in Northwest Iowa, came in higher than anticipated, said the publicly-traded company headquartered in Deerfield, Ill.
The project remains on schedule, with completion expected by mid-2016.
"We're making great progress," said Nick DeRoos, general manager for the Port Neal complex and project director for the expansion.
Snow, ice and subzero wind chills this winter impacted productivity, he acknowledged. "At times, we were working 30 minutes on, 30 minutes off, letting people warm up," he said.
High winds also played havoc with the work schedule. While DeRoos led a Journal reporter and photographer on a tour, winds gusted up to 50 miles per hour, causing the light soil at the site to swirl furiously, much like a sandstorm.
About 1,700 workers are currently on site, and another 500 are expected to join them over the next few weeks and months, bringing peak employment to about 2,200. CF originally estimated that number at 1,500 and later revised it upward to 2,000.
The peak construction period is expected to last until early 2016, somewhat longer than originally anticipated.
While many of the workers are from the tri-state region, the majority were recruited from around the country, with 43 states currently represented.
At daybreak, vehicles back up for miles along the gravel road that provides the only way in and out of the secured construction area. After clocking in before 6:45 a.m., workers scan their IDs before passing through stadium-like turnstiles. After the workday is finished in the late afternoon, it can take 45 minutes or longer for the sprawling parking lot to empty out.
At noon, the workers break for lunch in a massive tent-like structure that is heated in the winter and air-conditioned during the summer months. A giant American flag hangs on one wall of the temporary building, made with aluminum tubes and steel, with a white canvas tarp roof. It holds about 1,800 people. An identical structure next door is now being used to store parts and materials, but also will be converted to a lunch area as the number of workers grows.
With their lunch pails in hand, the hard hat-clad workers quickly find a seat at one of the dozens of picnic tables set up in long rows. Some heat up their food in microwaves or purchase beverages or snacks from vending machines.
Because the 350-acre construction site is so spread out, former school buses are sent out to pick up scores of workers and bring them to the lunch tent. Without that lift, they would spend most if not all of their 30-minute break walking back and forth.
With the steel and concrete structures in place, the installation of a series of large, specialized vessels soon will begin, DeRoos said. Scaffolding currently surrounds some of the components, allowing workers to add insulation before placement.
During the recent tour, DeRoos pointed out an absorber that will be erected in the ammonia plant. Imported from Shanghai, China, it is 164 feet long, more than 20 feet in diameter, and weighs more than 1 million pounds.
Like the absorber, other vessels are so heavy or bulky that they had to arrive on Missouri River barges. It had been more than a decade since the last time barges navigated the river upstream to Sioux City.
Scores of other materials and supplies have arrived via truck and rail.
In excess of 725,00 tons of stone, sand and gravel -- or 394,825 cubic feet -- are being brought in for foundations, new roads and the temporary parking lot.
By project's end, more than 165,000 cubic yards of concrete will have been poured.
In May, the largest continuous pour in Iowa history was executed with the installation of 5,283 cubic yards to form the pile cap for the urea synthesis plant. The 16-hour job took three batch plants, 85 concrete trucks, 900,000 pounds of rebar and a crew of about 200.
Smaller pours will continue as the construction progresses.
Nearly 18,000 tons of structural steel also will be used to build the plants, the equivalent of the combined weight of 5,997 Ford F-250 pickups.
This spring, the next phases of work, such as electrical wiring and piping, will ramp up. The number of welders on site, for example, will more than quadruple, from about 30 currently to at least 150, DeRoos said.
A labyrinth of 468,000 linear feet of pipe will be laid. If lined up end to end, it would extend 79 miles, from Port Neal to the Interstate 29 junction with Interstate 680 in Omaha.
A total of 758 miles of wiring will be installed, the distance from Port Neal to Little Rock, Ark.
Beyond the main construction zone, other work is ongoing or scheduled to begin this year.
A new well that will supply water both for the manufacturing process and to cool the plant is being built on the banks of the Missouri River. A new bridge was constructed to provide access to the lateral direction well, which will have the capacity to pump up to 9,000 gallons per minute.
A new entrance road, administrative building and rail spur also are scheduled to be built to the east of the primary construction site.
The expansion, when finished, will add 125 new full-time jobs, more than doubling CF's Port Neal workforce. Most of the new workers have already been hired and have gone through training.
Another 700 indirect jobs also are forecast to be generated locally, through the additional economic activity required to support the larger plant.
Editor's note: An earlier version of this story incorrectly identified the number of indirect jobs expected to be created by the project.