By Rusty Bradshaw

Independent Newsmedia

Air quality is important for residents in age-restricted retirement communities, and Sun Cities residents have mixed feelings about the air they breathe.

While some residents have concerns about air quality in the West Valley, having seen rapid growth from mostly farmland to urban sprawl over the years, others are less worried. Sun City resident Pat Woods, in an effort to become more informed, asked several questions about Northwest Valley air quality compared to metro Phoenix.

“Every day TV newscasters warn about poor air quality in the Phoenix metro area,” she said. “What about Sun Cities air quality? Is it better, worse or the same as central Phoenix?”

She also wondered who monitored the air quality.

Maricopa County has an Air Quality Department tasked with monitoring and regulating air quality countywide. The department maintains 24 computerized monitoring stations throughout the county, including two in the Northwest Valley — Zuni Hills, 109th Avenue and Deer Valley Road; and Dysart, Bell and Dysart roads.

Since it is physically and fiscally impossible to monitor the air in every location, representative samples must be obtained, according to Bob Huhn, MCAQD communications supervisor. These samples are determined by using the monitoring objectives and the spatial measurement scales. The network must be dynamic enough to maintain a current representative sample of the air quality.

Mr. Huhn said on average, the air quality in the Sun Cities is better than in Central Phoenix.

“One reason for this is that the density of population, traffic and pollution sources is less in the Northwest Valley than in central or south Phoenix,” he explained. “Also, typical daily wind patterns tend to go from west to east transporting pollutants with it, and at night a cooling atmosphere will tend to sink and transport pollutants to lower elevations, i.e. toward the Salt River.”

That may provide some relief to residents concerned about Northwest Valley air quality. But some believe mining in the Agua Fria riverbed create additional air pollutants that affect breathing.

“The primary concern about air quality that I have is the riverbed mining in Youngtown,” resident Mary Goitia stated in an email. “I am opposed to mining going on right next to peoples’ backyards. I am sure glad that I do not live in that situation.”

She also worries about Valley Fever.

“I don’t know if it is more prevalent near this mining or not, but would think that maybe it is,” she stated.

Sun City West resident Ed Allen believes any discussion of air quality should come after measurements are taken by a reputable laboratory comparing air quality in Central Phoenix with the Bell Road/Loop 101 intersection and with the center of Sun City West.

“I will say that we are always amazed at how little dust collects on surfaces in our home the five months we are up north,” he stated in an email.

Sun City resident Ken Gegg has lived in the area 22 years and he has no complaints.

Air quality concerns for Sun City resident Jim Green revolve around global warming.

“I do have concerns that the air quality in Sun City will worsen with global warming and disinterest in the residents and industries being proactive about our environment,” he stated in an email. “There have been more and more ‘air pollution’ days in Phoenix as the years progress. We need to do more about allergens, too.”

He believes SCHOA should pick up the leadership for residents regarding air quality.

“Many (Sun City residents) are frail and susceptible to pollution, (they) must know more about our air quality and what they can do about keeping it tolerable,” he stated.

SCHOA used to have an Environmental Committee, but it was dropped several years ago. SCHOA officials did not return a text by press time about why the committee was dropped and if it will be considered for reinstatement.

“I do not know if PORA ever had an Environmental Committee, but we do not have one now,” Rob Robbins, PORA of Sun City West board president, stated in an email. “We would start one if issues were brought up that needed our attention.”

Air quality issues, such as eight-hour ozone non-attainment boundaries and permits for new sources, are diverse and controversial subjects for Maricopa County residents, according to information on the MCAQD website, www.maricopa.gov/1244/Air-Quality. With its robust air monitoring network and mobile monitoring tools, the department strives to provide the most reliable and relevant air monitoring data to the public.

Mr. Huhn explained the county’s particulate monitors are sited in such a way as to capture an ambient air sample, which means the monitors should not be influenced by nearby objects like buildings or trees. In some cases the air sampler inlet is sited on the roof of a building with no other higher objects to interfere with the sample.

“But more often it is situated by itself on a platform away from all other objects,” he stated. “We try to make sure that the surrounding environment will not bias the ambient sample; for example, we would not place a particulate monitoring platform on a dirt surface.”

County particulate monitors sample for PM10 (particulate matter less than 10 microns) and PM2.5 (particulate matter less than 2.5 microns), including all particulates suspended in the air.

“We often run PM10 and PM2.5 monitors next to each other and here we can subtract the PM2.5 concentration from the PM10 concentration to get PM10-2.5, usually known as ‘PM Coarse,’” Mr. Huhn explained. “PM Coarse often comes from disturbed crustal material (i.e. dust), so dust-generating activities are a major source.”

PM2.5 is often thought of as smoke or combustion by-products, but can also come as mists or fumes, according to Mr. Huhn. Besides coming from combustion, PM2.5 can form secondarily from reactions where chemical vapors condense or sublimate into liquid or solid microscopic particles.

PM10 often comes from dust-generating activities where crustal material is pulverized and then suspended in the air. Major man-made sources include activities such as construction, agriculture, mining, dirt roads or other unpaved surfaces or the re-entrainment of road dust from vehicle traffic on paved surfaces, Mr. Huhn explained. Natural sources include dust storms, though dust storms can be intensified if they pick up dust that’s been pulverized from man-made activities, he added.

PM2.5 is often a product of combustion, so smoke from wood-burning fires, forest fires, diesel engines or other industrial combustion processes are common sources, Mr. Huhn stated. PM2.5 can also form secondarily from chemical reactions between other gases, such as ammonia, nitrogen oxides or sulfur oxides.

He added fireworks could single-handily put the county in excess for PM 2.5.

“We wish they were not legal but where they are we have no jurisdiction over them,” he stated. “Any legislation that would help keep our air clean and residents healthy we would be in favor of and restricting fireworks would help.”

Mr. Green had other “clean air” suggestions, many of which he believes people will view as restrictive.

“One example: Sun Cities area drivers should maintain their vehicles on a regular basis. Many older people do not do this,” he stated. “Trucks should be allowed (only) on certain streets in the residential areas. Many of our landscapers have old trucks that spew smoke. They should be stopped and given citations to end the smoke. Also, I am not certain that our emissions for licenses is forceful enough.”