If you've never attended a public meeting in Montgomery County, you might be well-advised to bring a dictionary, a slide rule and maybe a computer.

All of these items would have helped Maryland health officials last week as they tried to decide whether to grant Montgomery County a permit for a permanent sludge composting facility east of Rte. 29 near Calverton. A decision is not expected for at least 60 days officials said.

In the best tradition of Montgomery County public hearings, the state representatives heard a battery of local officials PhDs and "experts" expound on topics ranging from "dispersion rates of biological contaminants" to "the detrimental effects of aspergillus fumigatus on the respiratory system" - all intended to prove that a sludge composting plan will threaten health and produce a foul odor.

Reams of technical and complex testimony poured out during the two-hour meeting at Galway Elementary School in the Calverton area of Silver Spring.

"We make it our business to stay informed," one speaker said proudly.

The first inkling of the way the meeting would go occurred when Washington Suburban Sanitary Commission members set up a slide projector and screen for a presentation explaining how the sludge plan would operate.

When Ronald Nelson, state administrator of community health projects, asked the crowd of nearly 200 for a show of hands as to whether they needed to see the slides to discuss the issue, not a single hand was raised.

Instead, the Calverton Citizens Association Committee on Sludge began an orchestrated and documented "presentation" of their opposition to a composting facility one-half mile from their town.

Aaron Handleman, an attorney and legal counsel for the Calverton Citizens Association, led the attack. Citing legal cases the reference numbers, Handleman challenged the legality of the meeting, the absence of a hearing examiner, the decision to place the plant near populated areas and the fact that he could not contest federal funding of the compost facility.

When Handleman finished, Prof. Bruce Donaldson began. He said, "We are told that we are technically naive." But he said his group believed it had legitimate concerns about the evidence provided by the county's "experts."

He acknowledged that "the composting method is the most cost-efficient method of disposing of waste," but said that it represents a possible hazard to populated areas.

Dr. James Vaugh, who also spoke for the Calverton Association, read a "treatise" on aspergillus fumigatus. After explaining that this "biological contaminant" was a "secondary opportunistic invader of the lungs" and functions in temperatures between "X and Y degrees centigrade," he went on to say that 11.4 percent of the population is susceptible to this fungus.

"It's even worse in institutions," according to Vaugh, who said residents of the Great Oaks Mental Health facility in Silver Spring who already have respiratory problems would be threatened by the composting facility less than a mile away.

John David, an engineer representing the civic association, recited equations from the "Workbook of Atmospheric Dispersion Estimates" by D. B. Turner, an official of the Environmental Protection Agency (EPA).

Midway through his presentation, Nelson suggested that David put his speech in laymen's terms and "boil it down to the important facts," so both he and the audience might understand what David was talking about.

"It could mean 400 million spores," responded David, who quickly explained that he was talking about the possibility of determining "dispersion estimates of aspergillus fumigatus because there was no way to determine the continuous generation or time release or travel time to the point of interest."

Montgomery County residents weren't the only ones concerned with the proposed sludge facility, which would be located near the Montgomery Industrial park, close to the Prince George's County line. Prince George's County officials said the proposal smells-in more ways than one.

Rep. GladY's Noon Spellman (D-Md) said she considered herself an expert in the matter of sludge. She explained that her frequent trips up and down the Baltimore-Washington Parkway near the experimental composting plant in Beltsville have prompted her to become an expert on the "vile stench" that eminates from the temporary facility.

"To place a composting facility 12 times the size of the Beltsville plant near Calverton would be devastating....You may think devastating is a strong word, but it is not as strong as the odor near my residence," said Spellman, who noted that her Montepelier home is near the Beltsville experimental sludge composting site.

"The only thing we have discovered that the smell is good for is threatening the grandchildren. When they misbehave we tell them we will stop along the parkway and let them smell the stench," Spellman said.

The debate over the proposed composting facility has been going on since the Montgomery County Council recommended the site in 1977. It is located off Rte. 29, southwest of Tech Road in the Maryland Industrial Park.

Use of the 116-acre site was mandated in July 10 ruling by United States District Court Judge Lewis Smith Jr. He ruled in a civil suit brought by the Commonwealth of Virginia. Fairfax County and the District of Columbia against both Montgomery and Prince George's counties that both counties had to develop a means of disposing the sludge from the Blue Plains Sewage Treatment plant.

WSSC spokesman Art Brigham said the facility is scheduled to be in "limited" operation by August and full operation six to eight months later.

One objection raised by the local citizen's group is that the "limited" facility, which would process 400 wet-tons of sludge daily from the Blue Plains facility, would not be required to have the enviromenttal protections that are mandated for the permanent facility that will process 600 wet-tons a day.

The Calverton facility, which will have a smaller counterpart in Prince George's County east of Upper Malboro, according to the WSSC spokesman, will accept digested waste from the Blue Plains facility by truck. The sludge will be mixed with wood chips and turned into humus material suitable for use as fertilizer.

Brigham said the project will be the first public use of the technology developed at the Beltsville experimental composting site.