Whenever an insured files a claim for Florida sinkhole activity, the cost of the claim investigation is born by the insurance company. First, upon notice of the sinkhole development, the insurance company is obligated to make an inspection of the premises to determine if there has been physical damage to the structure, which may be the result of sinkhole activity. This may seem elementary, but this would mean that a vacant lot, for example, may not draw an investigation as there is no physical damage to the insured property.
It's a Sinkhole ... Now What?
Once the inspection finds damage consistent with sinkhole activity, the insurance company must engage a professional engineer or professional geologist to conduct testing to determine the cause of the loss within a reasonable professional probability. Thus, the insurance company must essentially do two separate things, before it would be entitled to deny an insurance claim: (1) determine whether sinkhole activity is present at the site, which has caused damage to the structure; and (2) if sinkhole activity is not present, an independent alternate cause of the damage must be determined. Many insurance companies fail to assure this second step, and instead deny claims without ever determining a reasonable explanation for the damage. In so doing, insurance companies may expose themselves to claims of breach of contract.
How to Test for Sinkhole Activity and Identification
Sinkhole investigations would ordinarily include two broad categories of testing. These include remote sensing techniques, most of which integrate geophysics. These include ground penetrating radar or electrical resistivity. Some engineers use a method known as multichannel analysis of surface waves, which relies upon seismic waves to identify unusual conditions in soils. These methods, while complicated, will rarely serve as an independent basis for concluding whether sinkhole activity is present at a particular location. This is because they are subject to considerable interpretation and can be impacted by other conditions at a site. Instead, regardless of the results, more "hands on" testing must be relied upon in completing an investigation.
The most common tests used in the second category of testing, referred to as geotechnical testing, include a wide variety of methods to determine the density of and types of soil present at a particular location. These test methods include hand-augured sampling of shallow soils, to determine the composition of the surface materials beneath a property. Engineering firms should also conduct some form of shallow cone penetrometer testing, to determine the relative density of the soil across the site.
Most importantly, standard penetration testing, or "SPT," should be done nearest the area of damage on the property. These tests may be at varying depths, depending on the depth of the limestone at the location. These tests are often driven to depths of 40, 50, 75 and sometimes more than 100 feet, depending on how deep the tests must go until competent limestone is identified. As with most test methods used for identifying sinkhole activity, the interpretation of the data collected can vary according to the expert retained, and is often the source of great conflict between the insured and the insurer.