By Brad Segall
SKIPPACK, Pa. (CBS) — Montgomery County officials say they have identified the substance that caused a stench in a number of homes in a Skippack Township housing developement on Sunday, forcing widespread evacuations (see previous story).READ MORE: Philadelphia Mother Pleading To Find Driver Who Struck Son In Hit-And-Run, 'Guardian Angel' Who Found Him
The source of the substance in the basements — now known to be gasoline — remains a mystery.
County officials say the gasoline somehow got into the groundwater of the neighborhood just off Route 113, creating high readings in three of the homes when the water seeped into basements.
Investigators expanded their evaluation to 171 homes and got positive readings in some of them, but most were found to be free of fumes.
Most of the residents are now back in their homes. Fire officials say once they ventilate the basements and flush out their sump pumps of the three homes with the highest readings, those residents will also be allowed to return home.
Officials stress that there was nothing particularly life-threatening about the fumes and their concentrations were below the level of combustibility.READ MORE: Philadelphia's Evil Genius Beer Company Giving Out Free Beers To Those Getting Vaccinated In May
Fire officials say they don’t know — and may never know — how the gasoline got into the groundwater.
“We’ve done some thorough investigations around back, and we do not see anything out of the ordinary,” says Skippack fire chief Haydn Marriott. “There’s nothing to lead us to a source of it at this point.”
There were no reports of anyone getting sick.
Authorities say they plan to return to the neighborhood over the next couple of days to continue testing, to make sure there’s no reoccurrence of the noxious fumes that chased many residents from their homes over the weekend.
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