One Maunakea telescope has been partially removed, but the building that housed it will remain standing until next year.
The Caltech Submillimeter Observatory is the first of five summit telescopes slated for decommissioning in exchange for the eventual planned construction of the Thirty Meter Telescope.
After months of delays, workers began taking apart CSO’s telescope in June, and more work will be done in September, but the removal of the facility and its subsurface infrastructure will have to wait until after the winter to avoid inclement weather.
CSO Director Sunil Golwala said crews have been working since June to begin dismantling the telescope, removing the panels that make up the reflective surfaces of the telescope’s primary and secondary mirrors. The secondary mirror, measuring about three-quarters of a meter across, was removed last week.
Next month, a 120-ton crane will be brought to the summit to remove the telescope’s larger components, including its 34-foot-diameter primary mirror — although Golwala said that without the fragile reflective components, the mirror is now just “a frame of steel tubes.”
The dismantling of the primary mirror is expected to take a few months, Golwala said, and will take place at the CSO parking lot on the summit. However, he said specific dates for the beginning of the process have not yet been determined.
An initial plan to remove the mirror would have extracted it from the observatory and transported it to Kawaihae Harbor in a single piece, but that plan was dropped in favor of the current plan, which will break apart the mirror frame into four pieces small enough to fit into standard shipping containers.
Golwala said that, with the reflective panels removed, the mirror frame can be safely exposed to the elements during the dismantling process.
Eventually, all components of the telescope, including both mirrors, will be sent to an observatory in Chile.
The CSO building, Golwala said, will not be preserved, but he added that much of the materials making up the facility can be recycled.
Although the demolition of the observatory won’t begin until the spring, general contractor Goodfellow Bros. will conduct interior demolition in the fall, and also will pump out the facility’s cesspool. Further underground infrastructure — which includes a six-foot-deep concrete foundation and underground electrical and communication conduits — will also remain until next year.
The full process, including the eventual restoration of the site, is expected to cost more than $4 million.
Email Michael Brestovansky at mbrestovansky@hawaiitribune-herald.com.
