Kenny and Ardith Lindquist’s Rockrimmon residence showed initial signs of trouble with their porch requiring multiple rounds of stabilizing cement truck deliveries, which was quite astonishing for them and the contractor. However, their concerns escalated as they noticed increasingly significant structural issues, raising fears that their home might be sinking into a collapsed abandoned coal mine.
The couple observed cracks in the walls, floor tiles, and the detachment of baseboards from the floor. They recounted distressing incidents, including a sewage-filled basement due to a damaged gray water pipe, sunken basement floors, and visible concrete beneath the stucco, suggesting a backward shift in the house’s position.
Their neighbor, Austin Rivenburg, faced similar challenges with the back of his house sinking, resulting in numerous foundation, wall, and ceiling cracks—damage that emerged after he purchased the property in 2018.
Suspecting a collapse in the Pike View Coal mine beneath their homes as the root cause, both households sought aid from the State Mine Subsidence Protection Program. The program, established with a $4.9 million fund, aims to cover repairs for such issues.
Colorado Springs has seen a significant number of claims related to mine subsidence, especially in Rockrimmon, totaling 44 claims filed between 2017 and 2022. The state indicated that the region’s geological conditions, particularly expansive soils and slab-on-grade foundations prevalent in houses built in the 1970s and 1980s, contribute to these problems.
However, determining the precise cause of the damage has been a slow process for the Lindquists and Rivenburg. Investigative drilling by state-hired contractors, conducted twice, aimed to identify whether the structural issues stemmed from mine-related subsidence or expansive soils.
Delays in the investigation have occurred due to supply chain disruptions, impacting the availability of drilling equipment. As a result, final reports on the cause of the problems are expected by the end of the year.
To discern whether the issues are due to mines or expansive soils, soil samples are collected and analyzed. Highly fractured bedrock with unusual patterns or voids in drilling results could indicate a mine collapse. The prevalence of claims in Colorado Springs suggests a combination of expansive soils and the presence of mines as contributing factors.
Chadwick Miller, an expert, explained that differential settlement, wherein sections of a house sink unevenly, doesn’t self-correct and may worsen over time. He described techniques involving steel piers and carbon-fiber straps used to stabilize homes affected by mine subsidence or foundation issues, which can cost from thousands to hundreds of thousands of dollars.
The State Mine Subsidence Protection Program may cover repair costs up to $100,000 or the fair-market value of the property before mine-related damage, solely for houses built before 1989. Notably, standard homeowner insurance policies do not cover mine subsidence, leaving homeowners reliant on programs like this for financial assistance.
Although the Colorado government has a protection plan, Rivenburg and others have criticized its functionality, suggesting that the initial intent for the fund was to establish insurance programs, as highlighted in a 1991 Government Accountability Office report.
The ongoing investigation aims to determine the extent of mine-related damage, potentially offering financial aid to affected homeowners.