Over the last two decades, there has been a dizzying amount of proceedings on the fate of the Waimanalo Gulch Sanitary Landfill, including multiple hearings by the state Land Use Commission and the city Planning Commission, with stops before the City Council and the state Judiciary along the way.

September 1989: The landfill opens on a 200-acre Kahe Valley site, next to Hawaiian Electric Co.’s Kahe Power Plant with about 64.5 acres to be used for landfilling and support operations. Waste Management of Hawaii is given a 15-year operating contract.

May 1999: The city, under Mayor Jeremy Harris, seeks to double the landfill’s capacity, and keep it open until 2017; and signs a new contract with Waste Management to continue operating it for 15 more years.

Sept. 16, 2002: The state Department of Health grants the city a modified permit application to raise the height of the landfill by 30 feet (to 430 feet), but requires it to stop operating by Dec. 31, 2005. In a press release, Environmental Services Director Tim Steinberger said: “We continue to move forward on our plan to close Waimanalo Gulch Landfill in five years.”

March 27, 2003: The LUC votes 7-1 to OK a 21-acre expansion and allows the landfill to stay open until May 1, 2008, but requires a new site to be named by June 1, 2004. It also calls for Mayor Jeremy Harris’ task force to present recommendations to the City Council by Dec. 1. Acting Environmental Services Director Frank Doyle calls the conditions “reasonable.”

Dec. 1, 2003: After five months of meetings, the Mayor’s Committee on Landfill Siting recommends to the City Council 4 sites — Ameron Quarry in Kailua, Makaiwa Valley, Maili and Nanakuli — without indicating a preference. The vote is unanimous, but only after four of the 15 members resign under protest after Waimanalo Gulch is left off the list. A month earlier, Ko Olina Resort developer Jeff Stone threatened to sue the city if the panel did not remove Waimanalo Gulch from consideration.

Nov. 23, 2004: After his committee was criticized for ignoring the five sites recommended by the Landfill Siting group and selected a landfill location in Campbell Industrial Park, Councilman Rod Tam proposes the dump go in East Honolulu’s Koko Crater.

Feb. 2, 2006: DOH fines the city $2.8 million for 18 violations over two years following a six-month investigation. Among the violations are exceeding the height limit and allowing excessive liquid buildup.

March 31, 2006: The City Council allows Hannemann’s veto of its bill requiring closure of the landfill by mid-2008. Several Councilmembers say while they voted with a 7-2 majority for the bill less than a month earlier, they no longer supported it.

April 22, 2006: The Hannemann administration announces it wants to use the landfill 15 years beyond its May 1, 2008, closing, until 2023. The plan includes expanding the facility by 92.5 acres.

July 10, 2006: A new Oversight Advisory Committee begins meeting on a monthly basis.

Feb. 21, 2008: DOH approves raising the height limit for the project. City officials say they need it open until 2010 while they consider waste disposal alternatives. Two days later, Senate President Colleen Hanabusa and the Ko Olina Community Association file a request to intervene in the upcoming LUC proceedings. Mayor Mufi Hannemann calls Hanabusa “out of her mind” to seek a shutdown and said it would take five to seven years “just to permit a new landfill.”

March 7, 2008: Less than two months before a May 1 deadline for the landfill to shut down, the LUC gives the city 15 months, until Nov. 1, 2009, to seek alternative site.

July 30, 2009: The Planning Commission votes 6-2 to recommend the landfill remain open until it is full (thus avoiding a Nov. 1 shutdown deadline), but requires the city to start identifying and developing at least one new landfill site by November 2010.

Sept. 24, 2009: The LUC votes 5-3 to allow the landfill to stay open for general solid waste 3 more years, through July 31, 2012, thus going against the Planning Commission’s earlier recommendation. It is allowed to be open beyond 2012 but only for ash and residue. (The matter is appealed to state Circuit Court, and then the Hawaii Supreme Court.)

Dec. 1, 2009: The LUC denies the city’s request to reconsider the July 31, 2012 deadline.

May 2010: Implementation of an islandwide curbside recycling program is completed. In fiscal year 2011, 71,000 tons is diverted from the landfill, an estimated 6 percent of the island’s solid waste.

January 2011: Ko Olina and other West Oahu beaches are closed after heavy rains caused wastewater to spill out of an active cell at the landfill, and make its way to the ocean. Among the items found are medical syringes at Ko Olina Resort.

August 2010: A plan to ship up to 36,000 tons of city rubbish in one year to Washington state is scrapped when Hawaiian Waste Systems fails to get necessary federal permits. The following January, a two-alarm fire burns bales of trash at Hawaiian Waste Systems’ storage facility in Campbell Industrial Park where about 10,000 tons had been stored there since the contract was nullified.

Jan. 20, 2011: An Advisory Landfill Site Selection Committee convened by Mayor Peter Carlisle begins meeting hoping to identify a site that will accept municipal solid waste, ash and residue from H-POWER, as well as construction and demolition debris waste. ENV instructs the task force not to consider Waimanalo Gulch Sanitary Landfill because it could not replace or supplement itself.

June 28, 2011: The city files an application to modify its 2009 special use permit, specifically to delete the provision asking for municipal solid waste to stop being accepted by July 31, 2012.

Nov. 29, 2011: The EPA orders the city and Waste Management to address storm water violations at the landfill that caused the January wastewater overflow and beach contamination following heavy storms. The parties argue that at the time of the storms, Waste Management was just months away from completing a drainage system intended to divert stormwater from the landfill.

April 20, 2012: The advisory landfill selection committee recommends 11 possible replacement sites, the top four of which are in Upland Kahuku and Upland Pupukea. “The next steps are for the city administration to further evaluate the sites, submit recommendations to the City Council for review and approval, and develop Environmental Impact Statement(s) (Committee exec summary) specific to the selected sites.” On the advice of a consultant, the committee later adds two additional sites to the top four: the Kahe Point Power Generating System (next to the existing landfill) and the Makaiwa Hills next to Makakilo.

May 4, 2012: The Hawaii Supreme Court sides with the city and overturns a requirement that the landfill stop accepting municipal solid waste by July 31, describing the LUC deadline as arbitrary, “inconsistent with evidence in the record and not supported by substantial evidence.” It remands the matter back to the LUC.

Sept. 14, 2012: The LUC remands the special use permit issue back to the Planning Commission to consolidate two pending applications filed in 2008 and 2012, respectively, update the record, and make a recommendation.

Oct. 9, 2012: Mayor Peter Carlisle dedicates a $302M third boiler at HPOWER, the city’s waste-to-energy waste facility. The new boiler is capable of burning 300,000 tons of mass annually.

April 23, 2015: Mayor Kirk Caldwell dedicates a long-awaited, $10.6M sludge-receiving station at HPOWER, has the capacity to take in 90 tons of wastewater sludge a day, 26,000 tons annually. Previously, up to 20,000 tons have been going into the landfill annually.

July 8, 2015: The Council unanimously OKs Resolution 15-167 calling on Caldwell to expedite landfill closure. Environmental Services Director Lori Kahikina testifies that while the city has taken great steps to divert sewage sludge, bulky items and shredded automotive residue to H-POWER, a landfill is necessary to deal with emergency situations

July 11, 2015: Waste Management and two top officials plead guilty to misdemeanor charges and accept responsibility for the January 2011 wastewater overflow and beach contamination. WMI agrees to pay $600,000 in fines and restitution.

May 18, 2016: The city informs the LUC it has reached agreement with all parties except Hanabusa to settle the case.

Aug. 17, 2016: After delays caused, in part, by the city and Ko Olina to settle the matter themselves, the Planning Commission holds its first hearing on the matter in nearly four years.

March 1, 2017: The Planning Commission votes to recommend to the LUC that the landfill be extended until it reaches capacity, provided the city select an alternate site by Dec. 31, 2022.

May 24, 2017: The LUC votes unanimously to send the case back to the Planning Commission after agreeing with the parties involved that the Planning Commission erred by, among other things, not providing commissioners and the parties a written copy of its recommendation, thus denying the parties a chance to challenge the recommendation.