The decommissioning of two telescopes on University of Hawaiʻi-managed lands on Maunakea is tentatively scheduled to be completed by 2023. This is according to an update provided by the university to the UH Board of Regents (BOR) at the board’s February 20 meeting at UH West Oʻahu. The California Institute of Technology (Caltech) Submillimeter Observatory and the UH Hilo Hōkū Keʻa teaching telescope are both making progress in the extensive decommissioning process, according to UH Executive Director of Maunakea Stewardship Greg Chun, who provided the update to the regents.

The BOR adopted a resolution in November 2019 directing UH leadership to strengthen its stewardship of Maunakea and report back regularly on the progress of 11 action items. The first action item in the resolution is the decommissioning of Caltech Submillimeter Observatory (CSO) and Hōkū Keʻa.

Telescope decommissioning process

The 2010 Decommissioning Plan for the Maunakea Observatories, a sub-plan of the Maunakea Comprehensive Management Plan, describes the four-step decommissioning process for the removal of an observatory followed by a site restoration to its original state, to the greatest extent possible.

UH’s Office of Maunakea Management (OMKM) is responsible for coordinating the overall process and coordinating with the State of Hawaiʻi and the Department of Land and Natural Resources. The respective observatory is responsible for preparing the Site Decommissioning Plan along with compliance and permit documents and implementing decommissioning.

CSO decommissioning update

The California Institute of Technology Submillimeter Observatory
The California Institute of Technology Submillimeter Observatory

CSO is the first telescope/observatory to undertake the decommissioning process after it announced it would cease operations. The deconstruction and site restoration work is tentatively scheduled to begin in 2021 and be completed by mid-to-late 2022. The financial responsibility of the removal and site restoration rests fully with Caltech. The decommissioning will include the removal of the dome, outbuildings and related infrastructure along with the restoration of the site. The astronomical instruments inside the observatory have already been removed.

CSO is now finalizing the draft Environmental Assessment (EA) after completing the required technical surveys, including an Environmental Site Assessment and a Hazardous Materials Assessment. Caltech commissioned a number of studies for the process including an archeological assessment, a cultural setting analysis, a hydrogeological evaluation, a biological inventory, a biological setting analysis, a traffic analysis and an asbestos/lead paint/mold survey.

Along with completing the draft EA, which describes the site as well as the potential impacts of the decommissioning process, CSO is also in the process of completing the historic preservation review, Draft Mitigation/Monitoring Plan and Decommissioning Funding Plan.

As part of the process laid out in the 2010 Decommissioning Plan for the Maunakea Observatories, CSO is also required to complete a Site Deconstruction and Removal Plan and a Site Restoration Plan, all of which are subject to approval by OMKM and the appropriate agencies (along with the necessary permits) before deconstruction can begin.

Hōkū Keʻa decommissioning update

telescope on Maunakea
The UH Hilo 24″ Educational Telescope, Hōkū Keʻa (foreground)

The deconstruction and site restoration of Hōkū Keʻa is tentatively scheduled to begin in early 2023 and take about six months. The project will follow the detailed process in the Decommissioning Plan for the Maunakea Observatories.

On February 18, 2020, the Maunakea Management Board approved UH Hilo’s Notice of Intent to decommission the Hōkū Keʻa telescope on the condition that the university simultaneously proceed with the planning and permitting for a new teaching telescope for UH Hilo students and the Hawaiʻi Island community. The process includes identifying a new location, possibly the Hale Pōhaku mid-level facilities on Maunakea. The university is financially responsible for the decommissioning of Hōkū Keʻa and establishing the new UH Hilo teaching telescope.

The university selected a construction project management firm in February 2020 to handle the planning and permitting for the telescope decommissioning that includes preparing the Environmental Assessment, hazardous material assessments, State Historic Preservation Division clearances, Conservation District use application, design/bid construction package and the archeological plan along with the community consultation, the Kahu Kū Mauna (Native Hawaiian volunteer community-based advisory council) review and acquiring the necessary permits.

The university is in the process of awarding a contract to identify a new location and begin the planning process for the UH Hilo teaching telescope, which would be considerably smaller than the current telescopes on Maunakea.