Beginning in the mid 1990’s the school district began receiving complaints about an unpleasant, musty smell. The district hired professional industrial hygienists to investigate the complaints, and in only a few cases was mold found. The mold was removed immediately by professional abatement companies with a result of “clean clearance” of all areas contaminated.

However, the complaints continued, and parents began to grow concerned about the long-term effects on their children’s health.

The high school’s 30-year-old heating, ventilating and air conditioning (HVAC) equipment is undersized and, district officials contend, no longer meets current ASHRAE (American Society of Heating Refrigerating and Air Conditioning Engineers) or School Facilities Board fresh air standards.

According to district officials, at the time of Corona’s design and construction in 1975, the system did meet air quality standards, but those standards have since changed, based on several factors including a dramatically increased enrollment during the 1990’s (from an average of 20 students per classroom to today’s 30-35 students per classroom), and a longer school years in order to meet the minimum number of classroom instruction days established by the Arizona State Legislature.

Combine those with record temperatures and high humidity levels, and the ever-aging equipment—90 percent of which is original—simply can’t do what is asked of it, they point out.

The Arizona School Facilities Board (SFB), created in 1999, was charged with evaluating all existing school buildings, identifying deficiencies and making necessary corrections to meet minimum State standards. One indicator of indoor air quality is based on carbon dioxide (CO2) levels. During initial inspection in 2001, Corona met minimum SFB standards.

From 2002 to present, occupants have periodically complained of stagnant air or a musty smell. Professional industrial hygienists investigated each time a complaint was made and their reports indicated there was inadequate ventilation causing increased relative humidity and accumulated indoor pollutants. A small amount of mold remediation work was completed at Corona del Sol in 2006 as a result of air quality testing.

In September 2006, Health Effects Group (HEG) was hired by the district to conduct a comprehensive indoor air quality assessment. The report indicated that during a normal school day, CO2 build-up in occupied classrooms and common areas exceeded acceptable specified levels according to standards set by the American Society of Heating, Refrigeration & Air Conditioning Engineers and the School Facilities Board. HEG reported that, “There is no evidence of any long-term negative effects for students and staff at Corona del Sol. The only persons who may have concern would be those with already-existing severe respiratory problems.”

In order to address identified concerns, the district formally requested emergency funding from the SFB in May 2007 to correct the HVAC deficiency. The SFB denied two additional requests. The district made a final appeal in February 2008 and was again denied.

But now the state is stepping in, and district officials hope that this independent air quality study will give everyone a clear and comprehensive picture of just what is going on inside Corona’s busy hallways and full classrooms.

Diane Eckles, chief of the Office of Environmental Health, informed district officials that the Department of Health Services anticipates choosing an environmental specialist by mid-July who will conduct a complete and comprehensive visual inspection of each of the buildings, with an emphasis on identifying the source of water leaks and visible mold growth.

In addition, following mold and carpeting removal activities, they will conduct simultaneous indoor and outdoor airborne mold tests to ensure that the major sources of indoor mold have been eliminated. This would entail collecting and analyzing air samples at several locations in school under normal operating conditions. Indoor carbon dioxide (CO2) concentrations will be measured at several locations in all of our buildings under normal operating conditions when school begins in August.  

In the meantime, the district has begun a four-phase construction project to resolve identified issues at Corona del Sol. The estimated cost of the project is more than $14 million.  Phase I consists of replacing an existing chiller with a larger capacity chiller, larger pumps, and the upgrade of electrical services.  These monies were available within the district budget and work was completed in May.

Phase II consists of installing a new supply loop for chilled water to classrooms and installing new exhaust fans to help reduce CO2 levels.  These funds also were available within the district budget and work will be completed when school begins in August.

Phase III consists of electrical upgrades and Phase IV construction consists of air conditioning unit installment in each classroom. Both of these phases require additional funding, which may come from the proposed Maintenance & Operations (M&O) Budget override the district will put forth to voters in the November general elections.

For more detailed information, visit the TUHSD Web site, www.tuhsd.k12.az.us, which is updated regularly.