They've put on retainer the most sensitive nostrils in the Keystone state.

They've consulted with meteorologists to gauge which way the wind blows, when and how strong.

They've hired engineers to adjust this and tweak that.

Now, Cranberry is poised to spend $700,000 to $800,000 in an effort to put a better cap on the odors that have been emanating from the Brush Creek sewage treatment plant since it underwent an overhaul and expansion six years ago.

"The only thing left to do is make a capital expenditure,'' said Cranberry Manager Jerry Andree, following a presentation to supervisors last week that was titled "Odyssey of an Odor Molecule -- Find it; Capture it; Manage it."

"Finding it" has been the easy part. Just ask neighbors who have been complaining on and off about the sewage stench since the $26 million "improvement" of the Freshcorn Road plant was completed.

The idea behind the overhaul was to expand treatment flow capacity; switch from a mechanical to a biological treatment process to reduce the repair rate associated with moving parts in a mechanical process; and, finally, sweeten the usual odors associated with sewage.

The first two goals were accomplished. The third is debatable, Mr. Andree acknowledged. He said the expectations associated with odor control following the plant overhaul were "unrealistic."

As neighbors complained about the smell, the township began its own odyssey of sorts: the search for a fix.

Over the past six years, consultants have been hired, ranging from odor panel experts with trained noses to meteorologists to engineers. Duane McKee, director of public works, said every aspect of the township's sewage treatment process has been evaluated and the odors that emanate from each part of the process have been described and quantified.

Mr. Andree said the information has been used to help engineers make an array of adjustments that resulted in some improvement. But, he said, the stink remains unacceptable.

The number of complaints stood at 142 calls in 2005 -- up from 62 in 2004. Though he's not happy with that, Mr. Andree said the rising number of calls is not necessarily an indication that the problem is worsening.

"It could be part of the awareness we've encouraged,'' he said, noting the township has a 24-hour answering machine for odor calls and an online complaint site. He said neighbors were asked to report any and all odors so that the township could correlate environmental conditions with processes.

Whether it's worse, stable or better, Mr. Andree said, it's still unacceptable.

"Existing assets can't accomplish what we need,'' he said.

The next step is to buy the ones that will, like a large carbon polisher, a device that would attach to one of the plant's five scrubbing towers and act as an odor filter. The air from each of the towers would be piped to the polisher, which would enhance the work of the scrubbers. The scrubbers sort of scrub the odor generated from the treated sludge.

Mr. Andree said he expected the township to spend $700,000 to $800,000.

The township plans to award bids in the first quarter of next year and finish construction, which could take three to six months, by the third quarter.

Despite the investment, he said, neighbors shouldn't expect miracles. A sewage treatment plant is never going to smell like a bed of roses.

"This would help," he said. "But, we've got to have realistic expectations. It's not going to take away every odor."