NASA’s plan to deorbit the International Space Station into the remote South Pacific Ocean is drawing sharp criticism from ocean conservation groups, who argue the agency is preparing to dump 460 tons of debris into the sea with no environmental impact assessment.
The ISS, which has been continuously occupied since November 2000, is approaching the end of its operational life. Under current plans, a specially built SpaceX U.S. Deorbit Vehicle (USDV) will guide the station on a controlled reentry into the waters off Point Nemo, the most remote point in the world’s oceans, by early 2031.
The USDV contract, valued at up to $843 million, calls for a redesigned Dragon spacecraft carrying six times the propellant of a standard Dragon. The sequence will begin in early to mid-2028 with initial descent maneuvers, followed by the USDV attachment in mid-2029 and the final reentry burn at the end of 2030 or early 2031.
Legal vacuum on the high seas
The Ocean Foundation, a Washington D.C.-based nonprofit, has published four specific demands: a full environmental impact assessment of both the seafloor debris field and atmospheric effects, public disclosure of all materials that will survive reentry, legal analysis under international maritime law, and closure of what it calls a legal gap.
“We believe this gap in international law needs to be closed, and the ISS deorbit is a vivid illustration of why,” Mark Spalding, president of The Ocean Foundation, told Space.com.
The problem stems from a peculiarity in space law. The 1972 Space Liability Convention requires compensation if debris damages another nation’s territory, but no equivalent exists for the high seas, which belong to no single country. Agencies that dispose of spacecraft in the ocean incur zero legal cleanup obligation.
The Ocean Foundation argues that the United Nations BBNJ Agreement (Biodiversity Beyond National Jurisdiction), which entered into force on January 17, 2026, requires environmental impact assessments for poorly understood activities in areas beyond national jurisdiction. The ISS deorbit, in their view, should trigger these requirements.
What will survive reentry?
Most of the station will burn up during atmospheric reentry at temperatures exceeding 1,400 degrees Celsius. But dense components such as truss sections, titanium fuel tanks, and heat-resistant hardware are expected to survive, scattering debris across the seafloor.
“The honest answer is, we don’t fully know. That is deeply troubling for a structure the size of a football field,” Spalding said.
Previous experience supports these concerns. When the Russian Mir station was deorbited over Point Nemo in March 2001, some 20 to 25 tons of debris survived reentry. Skylab’s uncontrolled reentry in July 1979 scattered pieces across Western Australia, and the town of Esperance famously fined NASA $400 for littering.
More troubling still, space debris already accumulates on the seafloor. The Apollo 13 Saturn V upper stage’s radioisotope thermoelectric generator (RTG) survived reentry and remains radioactive at the bottom of the Pacific Ocean, where it will stay for roughly 2,000 more years.
Cumulative atmospheric effects
The concerns are not limited to the seafloor. NOAA research published in 2023 found that approximately 10 percent of stratospheric aerosols now contain metals from burned-up satellites, including aluminum, lithium, and copper, with potential effects on ozone chemistry and atmospheric radiation balance.
Edmund Maser, a molecular biologist at the University Medical School Schleswig-Holstein in Germany, drew a parallel to historical ocean dumping practices. “Ocean dumping has historically been a short-sighted solution comparable to 80 years ago when it was considered a good idea to dump unused ammunition from World War II in the oceans,” he said. “Our future generations will hold us responsible for this.”
The ISS, at 460 tons, will be by far the largest object ever deliberately deorbited. Mir, the previous record holder, weighed 130 tons.
Alternatives considered and rejected
NASA evaluated multiple disposal options before settling on the Point Nemo plan. Disassembly and return to Earth was deemed impractical, requiring an enormous number of spacewalks and a new propulsive vehicle for each module. Boosting the ISS to a higher orbit was rejected because debris collision risk increases dramatically above 415 kilometers, reducing the mean time between impacts from approximately 51 years to fewer than 4 years. Uncontrolled reentry cannot meet the 1-in-10,000 public casualty risk standard.
Ewan Wright, a PhD candidate at the University of British Columbia and Junior Fellow at the Outer Space Institute, acknowledged the complexity. “We don’t know exactly what materials are on the ISS, and the surviving debris may be a hazard to marine life. But dumping it into the ocean is the least worst option.”
What comes next
The EPA is evaluating how the deorbit will be regulated under U.S. law but has no timeline for a decision. NASA’s own environmental impact statement concludes that “no substantial long-term impacts would be expected” from the controlled ocean disposal.
The Ocean Foundation disputes this conclusion and intends to push for a formal environmental review under the newly ratified BBNJ Agreement. George Leonard, chief scientist at the Ocean Conservancy, summed up the broader issue: “The debate over the disposal of the International Space Station underlies the fact that humans often fail to plan for the end-of-life of the stuff we produce and the ISS and a plastic fork aren’t so different.”