The University of Hawaii is investigating two fluid leaks from the chilling system of one of its observatories on Mauna Kea.

The university today said it notified the state Department of Health about the fluid leaks at the UH 88 inch observatory, which is operated by the Institute for Astronomy.

The fluid, which is estimated to consist of 70% water and 30% ethylene glycol, is commonly used as an antifreeze in cooling systems. An independent laboratory is being contracted to determine the exact mixture of the leaked fluid.

Ethylene glycol is classified by the Environmental Protection Agency as a hazardous substance and the state requires reporting of any spill of one pound or more. The federal government’s threshold is 5,000 pounds.

The two leaks were detected on Jan. 10 when telescope staff were unable to restart the system after it was turned off ahead of a winter storm in December, UH said. The leaks were located in a drain valve and a pump inlet tube and have been stopped and contained.

It’s unclear how much of the fluid has been leaked or if the leak was contained within the facility, the university said. The coolant system is estimated to hold about 480 gallons. The remaining fluid will be drained so an accurate estimate of leaked fluid can be made.

The chilling system will remain off until the investigation into the leaks is complete. The system reportedly had been working properly prior to the shutdown and had been restarted before without issue.