Roanoke Times
Copyright (c) 1995, Landmark Communications, Inc.
DATE: SUNDAY, August 1, 1993 TAG: 9308010104
SECTION: VIRGINIA PAGE: D1 EDITION: METRO
SOURCE: CATHRYN McCUE STAFF WRITER
DATELINE: LENGTH: Long
You can't see it from the street, but if you could it might conjure up a Spielberg movie or jetsam from a passing spaceship.
It's been up there for about five years. Mostly it just sits there, shiny and silent.
But every six days it jumps to life, sucking air out of the Roanoke skies like a hungry vacuum cleaner. Once a week, Jerry Ford visits the machine, named PM-10.
PM-10 is an air pollution monitor, one of about half a dozen scattered throughout the Roanoke and New River valleys.
The monitors, owned by the state Department of Environmental Quality, keep tabs on the quality of the air we breathe.
And Ford, an environmental specialist with the department's air division in Roanoke, keeps tabs on the monitors.
There are different kinds of monitors that test for different pollutants, but all gauge the quality of ambient air, as opposed to measuring stack emissions from specific industries.
"That's not loaded very bad," Ford said, after a quick glance at the charcoal gray filter taken from PM-10 recently. The filters are made of fine quartz fibers and look like heavy paper. They're white when new.
The machine is an updated version of the early monitors used in the 1970s, when black smoke spewing from smokestacks grabbed the public's attention and resulted in the first nationwide air pollution standards.
"Now you've got to worry about the stuff you can't see rather than the stuff you can see," Ford said.
Every six days, PM-10 kicks on automatically and takes in air for the next 24 hours. The air is pulled through the machine where larger particles are trapped by a series of filters.
The PM-10 monitor checks for the tiniest particulate matter, hence the "PM" portion of its name, measuring 10 microns or less, hence the "10." The width of a strand of hair is between 30 and 80 microns.
Ford said particles smaller than 10 microns can slip past our nose hairs and other biological barriers and into our lungs, where they can cause lung disease.
After taking some other measurements at PM-10, Ford will send the filter and his information for analysis at the state's lab in Richmond. There, technicians will measure and record the size of each particle.
These monitors are placed according to federal guidelines, usually in urban centers, where the majority of people live and work. There are 34 other PM-10s in Virginia, and about 1,500 in the country. All PM-10s suck in air on the same six-day rotation to establish a uniform databank on particulates.
In Western Virginia, there are PM-10s in Marion, Galax, Bristol, Covington, Martinsville, Lynchburg and Altavista. There used to be a second one in Roanoke, on Cherry Hill Circle near Roanoke Electric Steel Corp.
But in January, someone pried the aluminum top of the monitor off and fled, Ford said. "I felt like a cop, taking this picture of it around to the salvage yards and asking: `Have you seen this monitor?' " he said.
They don't come cheap. They cost about $3,600 apiece, and that doesn't include extra costs for fencing or additional power sources if necessary, Ford said.
Microscopic dust is one of six pollutants measured according to federal regulations established in the Clean Air Act. The others are sulfur dioxide, nitrogen dioxide, carbon monoxide, lead and ozone.
Measuring these compounds is a bit trickier and requires more sophisticated machines - namely, computers.
In Vinton, there's a shed surrounded by a chain-link fence behind the East Vinton Elementary school. Inside it's air-conditioned. But the pleasant chill is for the equipment, not for the operator, Ford noted.
To the untrained eye, the three machines on the shelves look like a stereo. These are continuous monitors, drawing in a steady stream of air through a tube that runs from the back of each one to outside.
Every minute or so they display a number that shows the concentration of ozone, sulfur dioxide or nitrous compounds - measured in parts per million. The information is sent via computer to Richmond, and eventually on to the federal Environmental Protection Agency.
The equipment costs about $40,000 to $50,000, Ford said, not counting staff time and $2,400 in annual maintenance costs.
In November, the state set up a carbon monoxide monitor on the corner of Williamson Road and Orange Avenue, figuring that if the auto emission pollutant would show up anywhere, it would be there.
The concentrations have been well below the standard, somewhat to the surprise of Don Shepherd, director of the air division in Roanoke. But he said there's not enough data yet to really determine the amount of carbon monoxide in our air.
Roanoke does not monitor for lead. The federal government requires only urban areas above a certain population to measure the pollutant, since the primary source for airborne lead is automobile emissions.
The federal standards for these six pollutants define acceptable limits for protecting public health and the environment. The state has a total of 92 monitors, concentrated mostly in Northern Virginia and in the Richmond area.
The region from Pulaski and Floyd counties to Frederick County met the federal standards for the five pollutants monitored in 1992.
The third type of monitor is sort of the clunker of the bunch, harkening back to the early days of measuring air pollution. It's called TSP for total suspended particles, and acts as a catch-all.
"Basically it's a vacuum cleaner, and when it kicks on it sucks in everything," Ford said.
On the federal level, the EPA dropped TSP measurements some years ago, although Virginia retains it as a legal standard.
When citizens complain of dust or grit from a nearby industry, or coal dust from passing trains, for example, the TSP is called into action. They are set up to monitor for specific problems, Shepherd said.
He and his staff often get inquiries from citizens, asking for a monitor to be put up because they suspect a nearby industry is sending air pollution over their home or business.
Although TSPs are relatively small and easy to move around, the cost to set one up can be as high as $5,000, Shepherd said. His office has only four TSPs for an area that extends from Pulaski County north to Winchester in a corridor about two counties wide. They are located in:
Giles County, near two lime extraction plants.
Covington, home of Westvaco Corp.
Radford, to monitor air quality around Lynchburg Foundry Co. and New River Castings.
Roanoke, on Shenandoah Avenue near Howard Bros. Inc., which processes and recycles slag from Roanoke Electric Steel.
Because they are somewhat crude in today's world of complex regulations and stew of airborne toxins, the TSPs have their drawbacks.
When folks began complaining a few years back about coal dust from passing trains blackening their lawns and homes, Shepherd figured he would need four stations along the entire train route - from the coalfields to the eastern shore port - with TSPs, PM-10s and weather gauges to get accurate information. Total cost: about $100,000.
Instead, the air division installed a TSP in Ironto near the Norfolk Southern Corp. track. Over the next 2 1/2 years, they found six violations of federal standards. However, there are no laws covering fugitive coal dust from passing trains.
"All we could do was tell [the railroad] what we found and hope they would do something," Shepherd said. His agency, the General Assembly and the railroad are still working to correct the problem.
Another problem with TSPs, Ford said, is that they're a hit-or-miss proposition when trying to determine the exact source of dust and other pollution.
Because they suck air once every six days (on the same rotation as other particle monitors), they may not be recording air quality at the same time the targeted industry is creating pollution. The weather is another variable - the temperature, wind direction, time of day, time of the year, and so on, Ford said.
"It's hard to prove. It's a 24-hour standard. You can't pick and choose your 24 hours," he said.
For instance, the air division installed the Shenandoah Avenue monitor about 16 months ago after homeowners and business owners in Northwest Roanoke complained of dust coming from Howard Bros.
"We've seen the dust clouds go into the air and seen it come down on the neighborhood," said Bob Saunders, head of enforcement in the air division's Roanoke office.
Dust billows into the air when trucks dump hot slag into piles along railroad tracks. The so-called fugitive dust is harder to control than emissions from a stack, Shepherd said. The state has been working with Howard Bros. for years to try to solve the problem, but so far there's been little progress.
But Shepherd's office has not issued fines or taken significant enforcement action because Howard Bros. is not breaking any rules, Shepherd said.
So far, the TSP filters have not exceeded state standards nor has the company exceeded visibility standards.
Shepherd said his office is continuing to work with Howard Bros. to try to find ways to control the dust. In the meantime, Ford will keep checking the filters once a week.
by CNB