Question and Answer Session with Press and Public


Staff member
Responses to questions asked at the August 1 Work Session:

1. Why is there not a separate line item? We agree that the agenda caption could have been clearer. A more descriptive caption was drafted; however, somewhere through the agenda review process it was not the version that was posted.

2. Why is cost of remediation not in packet? The exact cost of remediation is not known. The Voluntary Clean Up Program is a process with the Texas Commission on Environmental Quality (TCEQ) for clearance of environmental issues so the properties may be restored to economically productive use. Each clearance is based upon the conditions found. The initial estimate to achieve clearance was $225,000 which was the amount withheld at the time of purchase. The VCP certificate also provides liability protections, long-term, for the City, once the project is properly completed.

3. Why is cost of the consultant not in packet? Amount paid to Chapman Engineering to date is $124,076. This has been paid from the funds withheld at closing. It includes the cost for the drilling of monitoring wells, soil & water analysis, and handling the TCEQ VCP process.

4. Why hasn’t there been an analysis of the potential of a sinkhole? Sinkholes typically occur for two reasons. The first is due to improperly functioning utilities where soil is carried away, as seen when cars fall into a sink hole in a street. To avoid this type of occurrence the City’s Utility department performs leak detection on water lines, and smoke testing/camera inspections of wastewater mains. Sink holes can also occur in karst terrain where rock below the surface is dissolved by water. When the water is removed support is lost and the surface collapses (Florida is largely underlain by limestone and is highly susceptible to sinkholes.) In 2019 the City contacted a geologist with the Edwards Aquifer Authority on the susceptibility of sinkholes in San Marcos. Their response was the possibility of a sinkhole forming in a natural setting is very slight to non-existent. The karst terrain in this area being very stable due to a deep water table and thin soil layer over rock. We do not have karst terrain at or near ground surface in the South Guadalupe area. The karst area in Florida is very different and the type of sinkholes that have occurred there would not happen here. Texas sinkholes have typically been related to utility line failure or oil & gas exploration.

5. Can City provide an analysis on whether or not more high rises should be built on Navarro clay? The foundation design for any structure requires an analysis of the underlying soil’s ability to support the structure. A design sealed by a professional structural engineer is required for a building permit.

6. What is the remediation for this site? The type of contaminants and their levels (parts per billion) are such that an “active” remediation (removal of soil/groundwater) is not effective for this site. The analogy presented was trying to drill to find the one red ping pong ball within a Council Chamber filled white ping pong balls. The typical remediation process for this site’s condition is the monitoring of contaminants until they degrade to below potable (human consumption) water standards. Monitoring could be needed for many decades because these contaminants degrade very slowly. During this time there would be limited opportunity for use of the property, which is why the state created the Municipal Setting Designation (MSD). The establishment of the MSD removes the risk of potable groundwater use, thereby increasing the allowable level of contaminates being managed over time, and reducing the time for the clearance. It allows for the redevelopment of parcels to occur more quickly while still protecting public health & the environment.