Curt R. Peterson 0000-00-00 00:00:00
Recently, I received a call from the owner of an apartment complex in Arizona. The owner was concerned because one of the 5 year old apartment buildings had settled approximately 4-inches. The settlement had caused significant drywall and stucco cracks and racked the doors so severely that the tenants could not open some of them. Various repairs were performed on the building, but the distress continued to reappear and worsen. The owner had already hired one geotechnical engineer to determine the cause of the settlement, but various soil borings around the perimeter of the building only revealed dense sands, gravels, and cobbles extending to a depth of 10 feet. Most of the borings were terminated at a depth of 5 feet given the presence of this dense material. Despite the best efforts of the owner and the geotechnical engineering firm, it was unclear to all involved as to why the building continued to settle. In order to understand the cause of soil movement at a building, one must first understand the geology of the area and the past history of the site. My office reviewed a series of aerial photographs in order to see if any changes had been made to an adjacent wash or the apartment complex site. In 1949, the wash was approximately 500 feet wide in the area of the apartment complex. A 1969 aerial photograph indicated that the western section of the wash had been modified and filled in with what appeared to be soil. A 2005 aerial photograph showed that the apartment building experiencing settlement had been constructed over the filled in section of the wash. Given this new information, we were able to educate the owner on our findings and potential reasons why his building was settling. We performed additional soil sampling at the site using a large back-hoe to depths of approximately 20 feet. Buried citrus trees, asphalt debris, and leaves were encountered between 14 and 20 feet. Sampling by larger drill rigs discovered that the buried trees and debris extended to a depth of nearly 25 feet below the ground surface. Our evaluation revealed that the apartment building was founded on 10 feet of dense soil; however beneath this dense layer was decomposing debris that was causing the settlement at the surface. The owner was not aware at the time of construction in 2002 that the decaying material had been placed in the wash and filled over sometime between the years of 1949 and 1969. As a result, the current building owner had to spend hundreds of thousands of dollars to relevel the building and stabilize the underlying soils, all of which could have been avoided if the engineers and environmental scientists had spent a few extra minutes performing a simple aerial photograph review as part of their pre-construction studies. Most cases involving soil movement beneath a structure are not as dramatic as the example described above. But whether you are an attorney, geotechnical engineer, general contractor, or owner, understanding the cause of the soil movement is paramount. As an attorney, you need to understand which parties are liable and should participate in resolving the matter. It is very rare that a building exhibiting significant soil movement will only have one cause and one responsible party. If you have a project that you think may have soil related distress, consider the following: Was the foundation design inadequate and did it fall below the standard of care? If yes, then the original designers should be included. Was the soil beneath the structure prepared in accordance with the recommendations contained in the geotechnical report? If not, than the mass grader and possibly the compaction testing company should be included. Was the grading and drainage constructed in accordance with the civil plans? If not, then the rough and fine grader should be named as a defendant. Did the landscaping, which was installed by a landscaper hired by the general contractor, alter drainage and trigger soil movement? If yes, the landscaper should be named in the lawsuit. In conclusion, issues related to soil movement are common occurrences in Arizona. Some soil related issues are relatively easy to identify and correct, while others can be very complex and require unique methods of identifying and addressing the issue. As attorneys, having a basic understanding of soils and the role of the designers, general contractor, and sub-contractors have during the construction process will aid in resolving soil related lawsuits.
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