Phyllis Fitzgerald, Louisville Metro Air Pollution Control District

Phyllis Fitzgerald is a technical coordinator for the Louisville Metro Air Pollution Control District in Kentucky.

Yesterday I was on a real high following a positive presentation experience at the Kentucky Landscape and Turf Workshop. The participants were open to new information that could change their businesses, and a follow-up call produced a very interesting result.

One of the questions at the workshop came from a cemetery manager, who wanted to know about alternatives to the diesel mowers currently used to maintain the property. I was able to refer him to Melissa Howell, director of the Kentucky Clean Fuels Coalition, who gave him information about purchasing biodiesel fuel for diesel mowers. She called today to say that word had traveled fast, and she had been invited to speak at the Kentucky Cemetery Association meeting in June. This is a wonderful opportunity to inform cemetery managers about biodiesel, a much cleaner fuel for diesel lawnmowers.

Today is the day to finish researching the tougher questions raised by workshop participants and get back to the questioners. One person, a Metro Parks employee, asked if the Air Pollution Control District permits controlled burns, even though most other open burning is banned by the district. This employee recalled a burn conducted on a meadow in Iroquois Park last winter; she said that the meadow rejuvenated in a most magical way after the burn, and the parks staff was excited about burning other fields.

I worked with APCD Enforcement Supervisor Terri Phelps on controlled agricultural burns last year, so I knew that properly managed, burns mostly affect dry grass. Information we received in burn training last year indicated that these burns take only a short time and can be a good substitute to mowing. Our agency allows them if conditions are right and the if the burn will not create an ozone problem. Burns can only be used when the temperature, wind speed, and humidity reach optimum levels, and then only when the fire department can have crews nearby, trained burn crews are on site, and all of the neighbors and local authorities have been notified. It is unlikely that these conditions can be met between May 15 and Sept. 15. The parks employee was pleased to learn that there is still time to burn this spring.

As for other types of burning, Phelps confirmed that housing developers or farmers sometimes remove trees when preparing land for building or crops, and then want to burn whole trees and stumps. These may burn for days and create a lot of smoke, and most suburban farmers and developers know that they are not allowed to burn large woody debris. Compliance Officer Beverly Tyler told us a funny story about this: One day she noticed smoke from a large fire and drove up to it to determine what was burning. When she saw a large tree being burned and a stack of trees waiting nearby, she went to the car to get her camera. When she returned, one of the workers arrived with a package of frozen hot dogs on a tray, and invited her to a wiener roast!

This story leads me to the last question that stumped me yesterday: "What kind of pollutants are in wood smoke?" I had told the questioner that particulate matter (PM) was one of the most harmful substances in wood smoke, but I wanted to double-check on the others.

My research showed that wood smoke can also contain carbon monoxide, nitrogen oxides, and volatile organic compounds, including several toxic and/or cancer-causing substances -- but the biggest health problem is the PM. We have been burning wood for hundreds of years, but that doesn't mean it poses no threat to human health. Particulate matter can be so small (for example, PM 2.5 is 2.5 microns in diameter, while a typical human hair is about 75 microns in diameter) that when it is breathed into the lungs, it can be absorbed into the bloodstream. This is especially harmful to people with heart disease, asthma, chronic bronchitis, or emphysema. Our community does not meet the current standard for PM 2.5, so the U.S. EPA could eventually require our agency to find ways to reduce PM 2.5 from various sources. That is one reason that APCD bans open burning.

I relished the opportunity to pass this information on to the landscape worker who asked the question, and he seemed glad to be able to inform fellow workers, who, he confided, had been burning some of their woody debris.

This afternoon I thought about being able to share my own newly acquired understanding of the issues involved with diesel lawnmowers and particulate matter. I contacted some of my friends who teach in the landscaping field and shared this information so they can pass it on to their students and clients. Finding ways to provide information to teachers and industry leaders is enormously satisfying, for this is the way systems change, and (in this case) the way air quality improves.

The opinions expressed in this diary are those of the author and not necessarily those of the Louisville Metro government or Air Pollution Control District.