RICHFIELD — Another case of mysterious brown droppings, which apparently fall from the sky and plagued the Salt Lake Valley two years ago, has turned up here.
A home was splattered with brown droplets earlier this week, and the Federal Aviation Administration is examining whether the drops could have come from one of the commercial airliners that pass over the city.
But Utah Public Health officer Robert Resendes doubts a commercial airplane is the culprit in the inexplicable droppings.
Resendes, who inspected the home himself, describes the spots as "brownish-green rain drops" that are spaced about 3 to 5 feet apart. The material has tested positive for coliform bacteria, he said, which indicates it may be feces.
"I can't say it absolutely, positively is," Resendes said. "But it looked like feces and smelled like feces. If it walks like a duck and talks like a duck. . . ."
Similar droplets were found with regularity splattered on numerous western Salt Lake Valley homes in 1999. Many police and fire agencies pinned the causes on everything from mischievous neighbors with slingshots to misguided pilots in small single-engine planes.
This latest case is different from those in Salt Lake because the droppings appear to have fallen in a direct vertical path rather than at an angle, Resendes said.
"I'm totally perplexed, stumped," Resendes said. "They could be from a smaller airplane maybe; from that height you could get some type of evenly distributed splatter. But little planes don't have toilets."
FAA regional duty officer Mike O'Connor has a theory — opossums.
"I was up cleaning my roof one year and a found a bunch of little splatter marks and then I realized it was from opossums hanging in the trees."
And that theory may hold as much weight as any.
O'Connor does have a second hypothesis that may be more plausible — blue ice.
The stuff forms when a commercial jet's septic tank leaks and small amounts of the blue cleaning solution airlines use in toilets leak onto a jet's fuselage. Along with that blue solution comes water and some waste, O'Connor said.
At high altitudes the leak immediately freezes. When a plane lowers altitude and the air heats up, or the fuselage heats up significantly, the blue ice detaches from the plane and falls to the ground.
O'Connor has been with the FAA for 14 years and says he has handled some 40 complaints of blue ice during his career.
He said the callers he has dealt with all describe the substance as blue, not brown as has been reported in Utah. But there is a possibility, he said, that the blue solution could melt away, leaving only brown waste behind.
However, Resendes said the droppings have not tested positive for any type of dye.
Both the health department and the FAA will continue to investigate the case and look for possible answers.
Meantime, however, Resendes has his own theory: "liquid pennies from heaven."