A person pacing off the length of the salt mountains at the Atlantic Salt Incorporated docks, not far from the ferry terminal on Staten Island, walks a third of a mile before getting to the end of them. Their sides are sloped, about four stories high, and mostly covered with heavy vinyl tarps held down at regular intervals by sandbags filled with salt. Workers walk on a narrow path on top, and look small up there. Next to the salt mountains are the dove-gray waters of the Kill Van Kull, traversed by towering container ships, tugboats, and local industrial vessels. Gulls creak and wheel overhead, as do the clouds and winds and helicopters and flags and everything. After a while, if you lick your lips, you taste Chilean salt.

A front loader digs its bucket into the salt at an end where it is uncovered and dumps load after load into trucks, which then drive to road-salt sheds throughout the city and beyond. The woman in the office trailer at the dock refers all inquiries to a phone number at the company headquarters, in Massachusetts. Dan Adams, a facilities architect and salt expert at the company, explains that this particular salt comes from Chile’s Atacama Desert, known as the driest place on earth. In some parts of the Atacama, decades go by without a drop of rain. Even the roads there are made of salt. Mining machines dig into deposits four hundred and fifty feet thick—an ancient trapped sea—and then other machines crush the salt and sift it and treat it with anticaking agents. At a nearby port, it is loaded onto cargo ships about eight hundred feet long and a hundred feet wide, with drafts of forty feet. Each ship can carry fifty thousand tons of salt or more. A ton of salt costs the city fifty-nine dollars. The Staten Island mountains contain perhaps two hundred thousand tons of salt.

“That will all go in a couple of big snowstorms,” Dan Adams says. “The company has a public-safety responsibility never to run out, so right now it has more salt ships on the ocean and headed for New York. It usually takes about three weeks for the voyage from Chile. The ocean is unpredictable, and there can be backups at the Panama Canal, so we have to plan ahead. The way you can tell Chilean salt, it’s kind of pink. That’s from the desert’s reddish-tan sands. Other main sources of salt are Egypt, which has a gray salt, and Northern Ireland, where the salt is brownish, because of the peaty soil. In Baja, Mexico, Mitsubishi has huge evaporator plants making salt from seawater. The Mexican salt is a pure, dazzling white.”

Almost all the road salt used in New York City arrives by sea. Upstate New York has huge underground deposits of salt, but moving it hundreds of miles by train is much more expensive than transporting the same amount thousands of miles by ship. What keeps New Yorkers from skidding on icy streets is almost entirely imported salt. More salt mountains may be found at the ship-container terminal in Red Hook, Brooklyn, just across from downtown Manhattan. Viewed from a certain angle, the shining towers of Wall Street seem to rise from a pedestal of tarp-covered heaps of salt. In the past, the city was less careful about keeping them covered, and blowing salt drove local residents crazy.

Luis Rivera, who used to drive the limousine of Cardinal Edward Egan, the former Archbishop of New York, and is now retired, owns a small apartment building at 113 Columbia Street, across from the Red Hook salt mountains. “It used to be terrible,” Rivera says. “All the time was like you have a spoon of salt in your mouth. My front steps was always corroded—I had to replace them, keep them painted with sealant. We complained to the city, but at first they didn’t do nothing. The windshield of my car was leaking around the edges from salt corrosion. My friend took out the whole windshield, sanded the metal of the frame, resealed it. It cost me four hundred-some dollars—maybe four-sixty, with the tip.

“Finally, they put heavy tarps on the salt, like they have now. Then, last year, the hurricane came. We was scared, thought it would wash us away. My brother-in-law went up in the fourth floor of my building, and he saw the waves come in. They was headed for here, but when they hit the piles of salt they split! The water flooded all around us—President Street, Carroll Street—but we didn’t get one drop in our basement. Under the tarps I think the salt was O.K., too. That surface is like solid rock under there, and it stayed the same. I never complain about the salt no more. It saved us.”