Early on Monday morning, Shell announced that it would no longer pursue oil-drilling activities in the Chukchi Sea off the northwest coast of Alaska. Shell’s announcement has been a long time coming, and marks a major victory for all those who have opposed Arctic drilling as too risky and too much of a threat to the Arctic ecosystem and the planet’s climate.

Shell purchased its Chukchi Sea leases in 2008, but was precluded from drilling on its leases for many years. Among other things, legal challenges exposed flaws in the government’s environmental analyses and the BP Deepwater Horizon disaster resulted in a temporary restriction on Arctic drilling. In 2012, Shell finally received the green light to drill in the Chukchi Sea, but the company was woefully unprepared for the challenge: vessels were not ready, spill response equipment failed under testing, equipment spewed air pollution in violation of standards and one of its drill rigs was swept ashore in a storm on the way back to Seattle. In the end, Shell failed to complete a single well in 2012.

This year, when Shell finally returned to the Arctic, it did so under intense scrutiny. Government regulators ensured that Shell conformed to rules designed to protect vulnerable species like Pacific walrus. This meant that Shell could only operate one of its two Arctic drilling rigs and could only drill for a short window of time during the ice-free summer season. Activists protested the presence of Shell’s Arctic vessels in in Seattle and Portland, highlighting the risk of an oil spill in icy and remote waters—and the risk to the planet’s climate if Shell found and developed a massive oil reservoir in the Arctic Ocean. And Shell encountered at least one problem reminiscent of its failed 2012 season when one of its ice-breaking vessels struck an uncharted object, opening a gash in its hull.

Despite these challenges, Shell persisted with its efforts to complete an exploration well in the Chukchi Sea. But when the company final did so earlier this summer, it found that there was not enough oil to justify additional exploration at the prospect. In a press release, Shell announced that it would “cease further exploration activity in offshore Alaska for the foreseeable future.” In addition to the sub-optimal results from the exploration well, Shell cited high costs and challenging regulations as reasons for giving up.

Shell’s decision to retreat from the Arctic Ocean is great news for the bowhead whales, walruses, ice-dependent seals and other wildlife species that could have been devastated by an oil spill in this remote region. Local communities depend on marine mammals like these to support a subsistence way of life that stretches back for thousands of years.

Shell’s decision to leave the Arctic Ocean should be viewed as an affirmation of all those who joined together in opposition to Shell’s risky drilling schemes. Now that the immediate threat of oil drilling has ended, we can focus on crafting sustainable solutions for long-term health in this rapidly changing region.