(BIVN) – The hydrology of Mauna Kea was the subject of a presentation by Dr. Don Thomas in Hilo on Friday.

Thomas, a geochemist and noted groundwater expert on Hawaiʻi Island, shared his work studying the aquifer with the Mauna Kea Management Board.

Thomas explained how a complicated dike complex beneath the summit intercepts infiltrating rainfall recharge and greatly slows its transport toward sea level.

Thomas talked about the high level water in the flanks of Mauna Kea that was confirmed by two recent research holes drilled in the Humuʻula Saddle.

The Mauna Kea Management Board spent a portion of Friday meeting talking about the decommissioning of the Caltech Submillimeter Observatory, and how a hydraulic spill back in 2009 was complicating the environmental due diligence of the process.

Thomas downplayed concerns of aquifer contamination, as he explained how the rainfall recharge can take over 2,000 years to filter down to the aquifer.

“If water is taking that length of time, essentially, the likelihood of contaminants surviving that trip is pretty close to zero,” said Thomas. “There is an active, biological community within the geologic formation that even looks at diesel fuel and hydraulic oil as a food source and will break that material down.”