Landfill study indicates extended lifespan


According to a Feb. 26 memorandum by county engineering firm Short Elliott Hendrickson (SEH), the lifespan of the county landfill may extend to 2061, significantly longer than previously predicted.

The memorandum concerns an airspace survey of the landfill conducted by SEH on Nov. 27, 2023, and compares the survey results to a previous survey performed on Oct. 12, 2022.

“The objective of the airspace survey is to monitor airspace utilization, evaluate waste compaction/density using available tonnage data, and projecting remaining site life for future solid waste planning,” the memorandum states.

The study indicates that 26,370 cubic yards (CY) of airspace at the landfill were consumed between the two surveys, at a rate of about 1,925 CY per month or 23,098 CY per year.

It notes that this is a reduction in the rate of airspace consumption compared to a previous analysis in 2020, which estimated an airspace consumption rate of 3,174 CY per month or 38,039 CY per year.

The study indicates that, comparing the survey to the remaining constructed airspace, the landfill is 69,205 CY over the remaining constructed airspace available, although the report later adds that the volume calculations could be inaccurately high due to incorporating soil stockpiles, intermediate cover and other stored materials that could potentially be excluded.

It states that, comparing the November 2023 survey to the total ultimate airspace surface in the landfill, including the unconstructed cell 4B, the remaining airspace in the landfill is 868,289 CY and the landfill is 44 percent full by volume.

The study then discusses waste compaction at the landfill, stating that, based on tonnage data provided by the county, the approximate waste density between February and November 2023 was 1,337 lbs/CY, which it notes is below the 1,500 lbs/CY industry standard for municipal solid waste landfills.

However, it also comments that liner repair efforts on landfill cell 4A occurring during this period could have negatively impacted compaction rates due to the need to relocate waste.

The study also highlights that the county acquired a new compactor for the landfill in April 2023.

It then indicates, based on current waste filling and compaction rates, that the landfill will reach capacity in June of 2061, although it adds that this projected capacity could change as filling and compaction rates fluctuate.

The study adds that an average of the current airspace consumption rates and the consumption rates for the previous year would project the landfill’s lifespan to 2052.

It concludes by noting that a longer-term historical average of airspace consumption does not exist due to a landfill airspace analysis only being conducted once prior to the current study.

County Manager Derek Woodman commented in an interview that he was surprised and pleased by the conclusions of the study, which he highlighted contrast with the five- to 10-year life expectancy that was previously assumed for the current landfill.

He stated that the county’s improved approach to providing daily cover at the site, which has reduced the amount of space consumed by cover daily, and the new compactor are likely factors in the increased lifespan. 

Cell 4B also can be made far bigger than expected, Woodman commented, helping provide more space for storing waste, and thus a longer lifespan for the landfill.

Woodman stated that the county acquiring a scale to measure waste coming into the landfill was also a key element in the changing projection, noting that, according to data he had reviewed, the county was consistently overestimating the amount of waste coming into the landfill prior to its installation.

He concluded by highlighting that the increased lifespan of the landfill is good news for the county and will make efforts to replace or obtain additional land for the landfill less urgent.

“It really takes the urgency out of it, and now it’s just we gotta figure this out,” he said.

Landfill updates and

At the April 9 Archuleta County Board of County Commissioners (BoCC) work session, the board heard an update from Public Works Director Michael Torres on activities at the landfill.

Torres stated that the Solid Waste Department is still waiting for approval of the repaired cell 4A at the landfill from the Colorado Department of Public Health and Environment (CDPHE).

He indicated that the county submitted a report on the repair to the CDPHE, but received feedback from the CDPHE about questions and concerns, which SEH has since answered.

Torres commented that he hopes to have a response from the CDPHE in the next few weeks, adding, “That’s really what we’re waiting on to get things moving ... down there.”

He explained that, during the winter, a leachate pump at the landfill failed and that county staff are working to install its replacement.

He stated that the department is also looking at going out to bid on the construction of cell 4B and is performing survey verification of property lines and other steps to prepare for this.

Torres added that the county previously put the project out to bid last year but did not move forward with the project at that point.

He commented that he hopes the county can move forward with the project this year, although he was not sure if it would be fully completed since a significant amount of dirt and trash would have to be relocated for the project.

He stated that staff are beginning work on taking dirt out of the cell 4B area and are planning to use this dirt as cover dirt once cell 4A is approved by the CDPHE to help alleviate issues with cover shortages.

Torres concluded that staff are also working on moving scrap metal at the landfill and preparing for this year’s Big Spring Clean event.

Commissioner Warren Brown asked if Torres had made any progress on obtaining a message board at the landfill office area.

Woodman explained that this board could be located at the landfill and potentially others could be located on roads leading to the landfill to provide updates on its status.

He added that such message boards would also have to comply with the Americans with Disabilities Act.

Brown stated that a sign at the landfill could help communicate upcoming closures and other events to help keep landfill users, particularly waste haulers, informed.

Commissioner Ronnie Maez commented that he would like to know how much such signs would cost.

“If we don’t have it, we don’t have to put it, either,” he said.

“The cost of not communicating is pretty high, as well,” Brown replied.

“I think they do a pretty good job of it now,” Maez said.

Brown stated that he agreed that landfill staff try to communicate “very diligently,” but that he had spoken with citizens requesting better communication at the landfill.

Torres stated that he would look into the issue.

Commissioner Veronica Medina asked where the county is on relocating its recycling facility.

Torres stated that the county is in the “preliminary design” phase for such a relocation and is moving forward with having a design for a new recycling facility completed.

Medina then asked if there has been any progress on looking at other properties near the landfill for potential expansion.

She added that such plans might not be moving forward due to the SEH report stating the life of the landfill is longer than previously expected.

Torres stated that there are no current plans on this due to the number of other issues that the department is dealing with but that it could be something to pursue in the future.

Medina then asked if conversations are still ongoing with companies that were potentially interested in taking over landfill operations.

Woodman stated that these conversations have “kind of stalled” due to mergers, although there is still interest in the possibility.

He added that this project would have to go out for a request for proposals and that further conversations cannot occur without this since they could prejudice the process.

At the April 16 BoCC  meeting, the board approved two supplemental letter agreements with SEH for landfill consulting services for 2024 and for engineering services for cell 4B.

The consulting services were approved at a cost not to exceed $148,700, while the engineering services for cell 4B were approved at a cost not to exceed $164,000.

At a BoCC work session earlier in the day, Torres explained that the landfill consulting services involve assisting the county with monitoring and reporting at the site and with staying in compliance with the CDPHE.

He also stated that the engineering services will help the county start the bid process for the construction of cell 4B.

Torres indicated that the county has $1.7 million budgeted for cell 4B and that the costs of the project would likely be around $2 million.

He added that the cell would be “huge” (about four to five acres) and would likely need to be completed over multiple years.

Brown stated and Torres confirmed that the higher cost is due to a “misunderstanding” by the county of the size of the cell, with the final cell being larger than expected.

Woodman commented that he is hopeful that putting the project out to bid again may encourage lower bids and that staff doing pre-excavation work might reduce the cost of the project.