California Steel Industries

California Steel Industries has rolled and finished flat steel at Fontana since 1984, on part of the former Kaiser Steel site in the Inland Empire. The plant covers about 430 acres with roughly 115 acres under roof, and it buys slabs rather than melting its own. Products include hot-rolled, cold-rolled and galvanized sheet plus electric resistance welded pipe for construction, energy and manufacturing customers. Nucor holds majority ownership alongside JFE Steel, which makes CSI Nucor’s West Coast sheet operation; it set hot-rolled coil at $1,200 per short ton in late July 2026 as U.S. sheet prices hit multi-year highs. Nucor has announced a new galvanizing line at the Fontana mill. The company employs roughly 1,000 people.

The Fontana site’s story starts in 1941, when Henry J. Kaiser put a steel mill 50 miles inland from Los Angeles, far enough from the coast to be safe from attack, to roll the plate for Liberty and Victory ships. Kaiser Steel ran it for four decades and closed it in 1983, unable to fund the modernization the industry by then demanded. In August 1984 Japan’s Kawasaki Steel, now JFE Steel, and Brazil’s Companhia Vale do Rio Doce each took 50 percent of a new company built on the old rolling mills. The first slab went through the 86-inch hot strip mill on November 12, 1984, and the first customer shipment left less than a month later. Nucor bought Vale’s half plus another point from JFE on February 1, 2022.

Five product lines rather than one is the operative fact for buyers. Hot rolled comes in gauges from 0.0538 to 0.500 inches and widths from 36 to 72 inches, in low and medium carbon plus high-strength low-alloy grades. Pickled and oiled runs 0.065 to 0.250 inches through a tension-leveling pickle line. Cold rolled runs 0.011 to 0.134 inches. Galvanized runs 0.0098 to 0.138 inches with coating weights from G-30 to G-235, plus galvanneal at A-40 to A-60 and RoHS-compliant chemical treatment across the standard coated range. ERW pipe runs 6-5/8 to 24 inches outside diameter in walls from 0.156 to 0.750 inches, sold mostly to oil and gas transmission companies, with distributors taking the balance for load-bearing and low-pressure applications.

Downstream, the steel becomes framing studs, roofing, decking and metal lath for residential and commercial building, along with culvert, tubing, water and gas pipeline, rack systems, automotive stampings and appliance stock. Much of the volume moves through service distribution centers across the Western and Midwestern United States, with some sold into export markets. The quality management system is certified to ISO 9001:2015 across the full product line.

The company’s own history page puts headcount at nearly 900 and records more than $1 billion reinvested in the plant since operations began, to maintain, modernize and add capacity. CSI operates union-free and pays profit sharing to full-time team members twice a year.