The Thirty Meter Telescope has run into another legal obstacle, only this time it’s in the Canary Islands, the project’s alternative site.

A Spanish judge has overturned the concession agreement that allows the proposed cutting-edge instrument to be built on public land near the summit of La Palma’s highest summit.

In doing so, the judge agreed with a lawsuit brought by the Canary Islands chapter of an environmental group known as Ben Magec, Ecologists in Action.

The ecologists argued, among other things, that the concession agreement between the La Palma government, the Institute of Astrophysics of the Canary Islands and the TMT International Observatory is invalid because the TMT hasn’t taken control of the land as required by the law.

“This ruling puts the TMT back to square one, since, as the public land concession is prerequisite, everything that has been approved subsequently based on the annulled concession would be equally invalid,” the group said in a news release.

In a statement, TMT spokesman Scott Ishikawa said the ruling would be appealed.

“While we respect the court’s ruling in La Palma, we will pursue the legal process to retain La Palma as our alternative site,” he said.

Ishikawa added that Hawaii remains the top choice for the TMT, with La Palma being the backup site.

In a statement posted on its website, the Institute of Astrophysics of the Canary Islands said it would appeal as well.

The institute said that in 2019 the La Palma government, following approval by the Town Council of Puntagorda and a detailed environmental study, assigned the land to the institute. The concession was made conditional on a decision by the TMT within a few years, and the condition has not yet expired.

The statement went on to say that it will argue, in part, that the concession is valid under a 1979 international science treaty that was ratified by the Spanish Parliament.

Meanwhile, in Hawaii, the preferred site of the $2.4 billion TMT, the project remains on hold while officials await the recommendations of the Astronomy and Astrophysics Decadal Survey (Astro 2020), sponsored by NASA, the National Science Foundation and the Department of Energy, which will prioritize projects for future major U.S. funding. A report is expected later this year.

If the TMT figures prominently in the report, it could mean a sizable influx of cash from the National Science Foundation — as much as $850 million — but it might also trigger additional regulations that will add further delay.

Beyond the money issue, there remains the other problem of the opposition by many Native Hawaiians who hold Mauna Kea sacred and view the massive telescope as a symbol of Native Hawaiian oppression.

After preventing work vehicles from reaching the construction site near the mountain’s summit on at least two occasions in 2015, the movement seemed to gain momentum during the 2019 Mauna Kea Access Road clash that prevented yet another construction launch.

In its release, Ben Magec said, “We believe that the five years (TMT) has lost in La Palma should make them reflect on the arrogant and disrespectful strategy they have had, both in Hawaii and in the Canary Islands, emboldened with institutional supports and despising the reasons of the opposition to the TMT.”

The group went on to accuse TMT of colluding with local Canary Island officials to modify the laws allowing it to build in “a priority conservation area of the Natura 2000 Network and peripheral protection area of the Caldera de Taburiente National Park.”

Vicente Rodriguez, mayor of Puntagorda, told the Canary Islands newspaper El Dia that the TMT is so important to the island that “if we have to start the administrative process again, we will do it.”