Gov. Linda Lingle accepted the University of Hawaii at Hilo's final environmental impact statement for the proposed Thirty Meter Telescope project.

The document was released Friday, noting a few remaining issues as the university moves toward signing a sublease with TMT officials for the $1 billion project. The university and state officials still need to determine how scientists and staff will access the site and complete a sublease between TMT officials and the university. Construction is expected to begin next year and take seven years to complete.

"There are two broad opinions concerning the project's potential impact on cultural practices and beliefs," the report said. "(One) that Hawaiian culture and astronomy can coexist on Mauna Kea and impacts can be -mitigated and (two) any development on Mauna Kea would result in a significant adverse impact that could not be mitigated."

Other potential impacts, listed as less than significant, include displacement of "nonsensitive lava flow habitat and not unique geologic resources," visual impacts because of the observatory, use of energy to power the project, increase in trips to the summit area and temporary effects during construction.

Benefits, the statement said, include employment opportunities, direct contributions to the economy and astronomical pursuits. The observatory will have the telescope, an adaptive optics system and instruments in a dome, a support building and a parking area on a 5-acre site. The dome housing the telescope will be a calotte-type enclosure 180 feet high, will appear rounded and smooth and will have an aluminum-like exterior coating, the report said. An attached support building will be about 18,000 square feet. A visitor viewing platform and visitor rest room are included in the design.

Mitigation efforts are to include a design intended to limit visual and other impacts, a zero-discharge wastewater system at the observatory, cultural and natural resources training programs, an invasive species prevention and control program and other waste minimization and management programs.

Those efforts may not overcome some objections to the project; the final environmental impact statement acknowledged officials do not know how much impact ongoing work on Mauna Kea may have.

"From a cumulative perspective, the impact on cultural resources has been and would continue to be substantial, adverse and significant," the statement said. "The cumulative impact to geological resources in the Astronomy Precinct has been substantial, adverse and significant."

The observatory's headquarters will be located on the UH-Hilo campus, in the University Park of Science and Technology development.