From March 16 - March 20, 2009, a district wide radon survey was conducted by Colorado Vintage Companies (CVC). Business Services is proud to report that this district wide survey was conducted smoothly despite school being in session, and allowed DCSD to sample the air quality for traces of radon gas during normal, occupied hours, providing a time in motion study to truly determine any risks for students and staff.
CVC has completed their report on the findings of this survey, as attached. We are pleased to report that district wide, radon levels are below the EPA’s action guideline of 4.0 pCi/L with the exception of 11 rooms at a total of 4 sites. The sites with elevated levels are listed below:
Additional news provided by this survey is that mitigation efforts of last summer were successful at ZCES, in addition to meeting annual testing requirements as directed by the EPA
As the report provided at the right states, based on the number of rooms tested, the eleven rooms noted above are a relatively small portion needing further assessment. CVC recommends additional testing with a Continuous Radon Monitor to truly determine the need for mitigation efforts. If this additional testing shows continued elevated results, these areas will need to be more thoroughly investigated to determine proper functioning of the HVAC systems for these rooms and other similar factors before the determination for more significant remediation efforts can be ascertained.
Continuing the District-wide Radon Survey begun in March, Colorado Vintage Companies (CVC) returned during the week of April 20, 2009 to further investigate the eleven areas at the four sites suspected to have elevated radon levels.
Continuous Radon Monitors (CRMs) were placed in the eleven locations on April 20, 2009 and left in place until April 22, 2009.
After the CRM results were retrieved on April 22, CVC began diagnosis of the results to determine if adjustments to the HVAC systems would affect the radon levels during occupied hours. Over the weekend of April 25-26, 2009, CVC went back to the four sites with DCSD HVAC technicians and other maintenance personnel, and began making adjustments to the systems as able and necessary. After this work was completed, CVC returned on April 27 to redeploy the CRM monitors in the areas where adjustments to the HVAC had been made, and retrieving the monitors on April 29, 2009 once again.
In most cases, the minor HVAC adjustments had a positive effect on the elevated radon levels – bringing them under the EPA’s action guidelines of 4.0 pCi/L. Improved fresh air flow reduced the amount of radon gas in the rooms. The second set of CRM test results show that there is no need for additional remediation.
The exception to this is George Whittell High School. CVC did not make many adjustments to the existing HVAC system as this system is scheduled to be completely replaced over the summer break with Bond funding. This changeover would negate any HVAC adjustments completed prior to the system replacement. CVC’s recommendation was to install the new HVAC/Boiler system and then re-test radon levels upon completion. Re-testing will be scheduled at an appropriate time in the future.