from the field
By Linda Mayfield
Mariposa County USD receives award for improving air quality

he Mariposa County Unified School District, a small, single-district county located in the foothills adjacent to Yosemite National Park, recently received a Notable Achievement Award presented by the U.S. Department of Energy and Lawrence Berkeley National Laboratory.

The award from the Efficient and Healthy Schools campaign recognizes schools and school districts that have implemented exemplary solutions involving HVAC upgrades and other approaches to reduce energy costs, and improve energy efficiency and indoor air quality. Improving air quality for the county’s students and staff had been at the forefront of the district’s concerns in recent years due to the increase in unhealthy air quality days at its schools as a result of wildfire smoke in the county. While multiple stopgap measures had been implemented, an ultimate resolution had not yet presented itself.

With the onset of the pandemic, it became clear to district administration that the need to ensure all facilities delivered the best air quality available for students and staff was imperative. Proper ventilation and air filtration were critical components that needed to be addressed immediately and focusing on ventilation made sense for the district. For a small, rural school district with very limited funding, the way was not always clear — it was also important to make sure that available Elementary and Secondary School Emergency Relief funding was spent wisely. District staff began to analyze the flood of information that was suddenly available; companies suggesting their equipment could solve air quality concerns suggested the purchase of air scrubbers, filters, etc.

Science work
Improving air quality for the county’s students and staff had been at the forefront of the district’s concerns in recent years due to the increase in unhealthy air quality days at its schools as a result of wildfire smoke in the county.
This triggered the start of the district’s research journey, working as a team to decide which options best fit Mariposa County USD. Ultimately, the district purchased and changed filters, upgrading where possible to the highest MERV (minimum efficiency reporting value) rating, cleaned registers to eliminate any additional dust that could penetrate the classroom, and installed over 100 Pelican thermostats, which allow the district to regulate a comfortable temperature for students and staff while retaining a focus on energy efficiency. The new thermostats have provided the Mariposa County USD with a user-friendly operation and ventilation management system. In addition, utilizing economizers on facility rooftop units as part of the solution, allowing the cooler morning air in, and adjusting as the temperature warms, provided both savings on utility costs and delivering desired air quality for our region.

The district also elected to pursue several programs, including Assembly Bill 841, which provides grant funding through the California-Schools Healthy Air, Plumbing and Efficiency Program (CalSHAPE). The grant assists with monitoring, filtration, assessments, ventilation rate and general maintenance. Assessment of current equipment is a necessity and provides the foundation for developing a replacement plan for all school sites. The district also participates in the Energy Star program, which assists with tracking usage and identifying buildings in need of improvement. The third program that is being implemented is the Sierra Nevada Energy Watch (SNEW) program. SNEW works with Pacific Gas and Electric (PG&E) assisting with district-wide equipment and energy usage. Energy Star and SNEW are free to any district looking to deliver quality solutions to existing buildings.

Window showing the outdoor sky
In addition to grant funding, the district is also utilizing local bond funding, which will allow for the removal and replacement of more than 75 outdated HVAC units. Two of the district’s elementary schools will receive all new HVAC units beginning in June 2022, a project that has been a long time in the making. During the HVAC audit process the evidence was clear; 80 percent of the districts’ HVAC units had outlived their useful life. Most were well over 25 years old, making it challenging to keep the units running. As a small, rural school district with limited funding, replacing HVAC units was not feasible in prior years and there were multiple other obstacles.

Due to the district’s location, the limited availability of specialized vendors meant that the district relied on its own maintenance team to repair units. Staff training has been a goal of the district’s from day one; however, staff was not always able to repair the 25-year-old units, and during the pandemic, most parts were unavailable. During the shutdown of schools, the maintenance team trained themselves and each other as they continued to improve each school site.

Superintendent Jeff Aranguena and Director of Maintenance Linda Mayfield pinpoint the availability and implementation of available programs, as well as the dedication of the maintenance staff, as factors that led to Mariposa County USD receiving the Notable Achievement Award.

Linda Mayfield is Mariposa County USD’s director of Maintenance. She has worked at the district for four years.