(NEW YORK) -- The bottom of the Chukchi Sea, off Alaska's north shore, is one of the most hotly contested places under the sea.
It is here that Shell Oil, Co., is looking for oil and Greenpeace is trying to stop them.
The oil giant has spent years and billions of dollars jockeying to be first to strike and the payoff stands to be enormous. The ocean floor inside the Arctic Circle may hold a quarter of the Earth's undiscovered oil, enough to drastically reduce the United States' dependency on foreign supplies.
Shell has promised to drill safely and responsibly, developing new technologies to reduce drilling noise, and dedicating a fleet of vessels ready to respond to a spill in 60 minutes, 24 hours a day.
But that's not how Greenpeace sees it. The environmental activists made famous for chaining themselves to things are now trying a different approach: going after Shell with science. That's where Greenpeace activist and marine biologist John Hocevar and the organization's Arctic floating research hub, a former Russian Army fireship Greenpeace dubbed the Esperanza, came in.
Life on board is what you might expect: tofu for lunch, a very serious recycling program, and an eclectic crew from all over the world who dedicate their lives to the cause.
Nightline was given the rare opportunity to go on a research dive with Hocevar in a two-person submarine deep below the Chuckchi Sea, one of the most remote oceans on Earth. It is a dive no one outside of the military had attempted before.
About 200 feet down, the world outside of the submarine is murky, so thick with plankton and sea worms, it's difficult to see. Slowly, Arctic life revealed itself and a sea bed covered in thousands of star fish, the occasional crab and other unworldly creatures appeared.
"We are right in the midst of Shell's proposed drill sites," Hocevar said.
While on the dive, Hocevar discovered a tiny coral, just one of the many examples environmentalists say offer insights into what fragile, new life might be at stake.
"We're rushing ahead to allow drilling in the Arctic and we don't even know what's down here," Hocevar said.
While Greenpeace continues its fight, Shell has found other support in some unlikely corners, such as Bob Reiss, an environmental journalist and the author of the The Eskimo and the Oil Man, who supports drilling in the Arctic.
"Are Americans going to buy the same amount of oil whether or not it comes from Russia or if it comes from Alaska? Yeah. So what's the downside of not taking out this oil?" he said.
Reiss said that Shell has more than cooperated to find solutions to environmental concerns.
"Shell bent over backwards over the last five years to compromise here," he said. "Their safety system has been called the gold standard by the Deepwater Horizon Commission. So I think if a company does bend over backwards, they ought to be rewarded for it."
That reward came this summer from the Obama administration, which gave Shell the green light to drill 1,400 feet below the surface of the Chuckchi Sea.
Shell declined Nightline's request for an interview, but said in a statement: "The debate on whether to evaluate Arctic energy resources is over. We are now focused on safe execution."
But Greenpeace refuses to back down, and the threat of a spill in the Arctic's pristine setting fuels their mission to stop oil drilling.
"In this remote, unforgiving environment, we all know it would be impossible to clean up an oil spill," said Greenpeace activist Jackie Dargon. "We can't risk it."
Reiss admitted than an oil spill in this part of the world, or in any part, could be catastrophic.
"The question is legislating perfection," he said. "Do you stop any kind of development because a spill could occur or do you have systems and back-up systems and other back-up systems to deal with a spill, which Shell does, and then allow it to proceed."
Local Eskimo communities whose culture and livelihood depend on a thriving Arctic are torn because for them, this debate is about survival. Steve Omittuk, the mayor of Point Hope, Alaska, located near the most northern part of the state, said the town has concerns for the animals and the ecosystem.
"If [the animals] are gone, our way of life is gone, the people who have been here for thousands of years is gone," Omittuk said. "The Arctic is so delicate, the system so sensitive."
But at the same time, Omittuk acknowledged that the town also needs jobs and drilling would provide them.
"It's hard for the people," he said. "They need money, they need income, they need our economy to come up, but we need our way of life also. It's a tough battle to choose."
Shell has already begun preliminary drilling and next year looks set to be full steam ahead.
Copyright 2012 ABC News Radio