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Public Information

Although most of the information on this wiki is aimed at professional observers, the following material may interest a broader audience.

Decommissioning information

Caltech has decommissioned the CSO and restored the site. The telescope ceased scientific operations in late 2015, after which all astronomical instruments were removed from the facility. Decommissioning of the CSO was carried out according to the Conservation District Use Permit (CDUP) issued by the State of Hawaiʻi's Department of Land and Natural Resources (DLNR) in January 2022. CSO is the first observatory to be removed under the 2010 Decommissioning Plan for Maunakea Observatories.

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Facility Deconstruction and Removal

The CSO dome and other buildings have been deconstructed and removed from Maunakea. Removal of foundations and underground structures is complete. Active site restoration is complete. This page chronicles some notable steps in the process, with photos:

Facility Deconstruction and Removal

Telescope Disassembly and Removal

The Leighton Telescope of the CSO has been disassembled and removed from Maunakea. It was transported to the Kawaihae Harbor and will be shipped to Chile for reuse. This page chronicles some notable steps in the process, with photos:

Telescope Disassembly and Removal

Consultants and Contractors

A partial list of consultants, contractors, and subcontractors decommissioning the CSO on behalf of Caltech.
Decomissioning Consultants and Contractors

Documents

Phase II Environmental Site Assessment

pdf. This report is very similar to the Soil Sampling and Remediation reporting (below), but the Phase II ESA was a requirement that emerged from the Phase I ESA (Appendix B of Appendix A (Site Decommissioning Plan) of the Final Environmental assessment, below) and thus this additional document was prepared.
- The above report was submitted to HDOH. Submission confirmation: pdf
- When the report is accepted by HDOH, the acceptance letter will be posted here.

Decommissioning Reporting

Provided below are the decommissioning reports listed in the Final Environmental Assessmentʻs Appendix I (Best Management Practices Plan) Section 5.2 (Reporting Plan) (pdf).

Archeological Monitoring Summary Report:
- Report accepted by SHPD (November, 2024): pdf
- SHPD acceptance letter, 11/22/2024: pdf
Cultural Monitoring Summary Report: pdf
Invasive Species Summary Report: pdf
- Also addresses the reporting item “A log of work conducted by and incidents and observations made by the invasive species monitor (Section 2.4), including vehicle inspections and site inspections.”
- Yearly reports on restoration monitoring in 2025, 2026, and 2027 will be posted here when available.
Independent Decommissioning Project Manager (IDPM) Summary Report, including Log of Incidents: pdf. Addresses the reporting items:
- “A log of incidents and observations occurring within the CSO Site and staging areas”
- “A log of incidents and observations occurring outside the CSO Site and staging areas”
- “A log of emergency situations (i.e., health emergencies, accidents, and fire) and maintain records summarizing response actions, timeliness, and lessons learned” [sic]
- “At completion of the project…A short summary of lessons learned.”
Hazardous Materials Monitoring. Not explicitly listed in Reporting Plan but an appropriate supplement to above summary reports, these reports summarize results of monitoring for airborne hazardous materials during lead-based-paint mitigation during observatory deconstruction.
1. Monitoring during pre-deconstruction internal removal of lead-based paint: pdf
2. Monitoring during observatory enclosure deconstruction: pdf
Soil Sampling and Remediation Reporting. This reporting details the previously planned soil sampling under the cesspool and foundation as well as added sampling in response to an equipment hydraulic fluid leak incident noted in the IDPM Summary Report.
- Initial soil sampling report: pdf.
  - No contamination was found in cesspool and foundation samples (DU-1, DU-2, DU-3).
  - Contamination was found under the asphalt where the hydraulic fluid leak occurred (DU-4).
- Removal Action Report: pdf. Includes summary of original measurements of DU-4 identifying contamination, soil removal to address the contamination, summary of measurements of removed soil and area from which soil had been removed, and summary of haul-off of removed soil.
  - The above report was submitted to HDOH. Submission confirmation: pdf
  - HDOH accepted the above report and found that no further action was required: pdf
Materials Storage and Waste Management Memo: pdf
- Addresses the bullet “A log and any data related to the Materials Storage and Waste Management Plan inspections or issues.”
Log of Materials Removed
- Addresses the bullet “A log (and copies of manifests) of all materials removed from the UH Management Areas from the CSO Site for recycling and/or disposal.”
- Summary: pdf
- Logs referenced in the above two reports:
  - Log of HELCO removal of HELCO Transformer: pdf
  - Northwest Demolition and Dismantling Materials Removed Log (above-ground structures; open using Acrobat for proper formatting): pdf
  - Goodfellow Brothers Materials Removed Log (foundations and below-ground structures): pdf
“A log of all vehicles (contractor, subcontractor, vendor, etc.) with each ingress and egress from the UH Management Area logged (vehicles equipped with radio- frequency identification (RFID) tags, if any, need not be logged).” – all vehicles had RFID tags.
IDPM Weekly Summaries including Daily Reports: zip of pdf files. Addresses the items:
- “A daily log of weather conditions recorded on the CSO Site.”
- “Documentation of the CSO Site weekly with photographs taken from roughly the four ordinates (e.g., north, south, east, and west).”
- “Copies, in electronic format, of the logs listed above” for all but the Materials Removed Logs, which were already provided above.

Final Post-Restoration Site Topographical Survey

pdf format
dwg.zip CAD format
topographical data in csv.zip format

Final Grading Drawings

National Pollutant Discharge Elimination System (NPDES) Permit

Received from Hawaii Department of Health on May 4, 2022:

Permit: pdf

Conservation District Use Permit

Approved by BLNR January 14, 2022; issued by DLNR, January 18, 2022; returned by Caltech January 24, 2022.

CDUP (pdf)

Final Environmental Assessment

Published December 8, 2021:

Body: pdf (16MB)
Appendices A, B, and C of the EA: pdf (51MB)
Appendices D through J of the EA: pdf (24MB)

Draft Environmental Assessment

The Draft EA was open for public comment September 8, 2021 - November 4, 2021:

Body: pdf (19MB)
Appendices A, B, and C of the EA: pdf (47MB)
Appendices D through J of the EA: pdf (24MB)

The public comment period has closed.
~~Comments should be submitted to~~
~~Planning Solutions, Inc. Attn: Mākena White, AICP 711 Kapiʻolani Boulevard, Suite 950 Honolulu, Hawaiʻi 96813 cso-decom@caltech.edu~~

There were three public workshops, conducted via zoom, presenting the Draft EA with Q&A. Recordings of each meeting can be found below:

Tuesday, September 28th, at 11:30 a.m. recording (mp4)
Wednesday, September 29th, at 4:30 p.m. recording (mp4)
Thursday, September 30th, at 6:00 p.m. recording (mp4)

Background Information

Archive of CSO construction and site plans: link to zip file (111 MB)
Historical photos related to Maunakea summit and CSO site: link to zip file (748 MB)

Submitted Documents

The Final Environmental Assessment is available above and from the Environmental Review Program
The Draft Environmental Assessment is available above and from the Environmental Review Program
The Center for Maunakea Stewardship (CMS) maintains a page with other public decommissioning documents: Link
- Direct link to CSO's Site Decommissioning Plan: pdf
- Direct link to CSO's Notice of Intent to Decommission on DLNR website: pdf