(WBIR-Knox County) A dozen homeowners filed a lawsuit against developers, demanding answers about a possible sinkhole in their upscale West Knox County neighborhood.

The Glen at Hardin Valley features brick homes valued at roughly a half million dollars, but many who live there said they would not have purchased their homes had they known they were built near a possible sinkhole, which is currently a pond under construction.

"Is there a cavern underneath? Is it dirt? What's going on? And once we know what's going on, we will hold the developer accountable," said Sage Kohler, who lives in the affluent neighborhood.

Kohler and 11 other homeowners paid a geotechnical engineering firm to drill Thursday to find out the possible danger of a sinkhole opening in their backyards.

"This is one of the things we've been asking for for some time. And we had to go to court and spend four days with a judge to get the injunction to allow us to just to be able to do this," said Kohler.

"We have been concerned because there has been a lot of heavy equipment maneuvering around the sinkhole," said Jeff Gilbert, a homeowner. "We don't know that the sinkhole represents that danger that we saw unfold at the Kentucky Corvette museum, or in Florida where someone died, but that's our issue."

Gilbert, along with all of the residents listed in the lawsuit, posted "For Sale By Owner: Lawsuit Pending" signs in their yards Wednesday.

"Based on the data and documents that we have available, the developer, Ben Testerman Construction Company, appears to have been clearly aware of a sinkhole," claimed Gilbert. "This is the original survey of our neighborhood, clearly delineating that there is a sinkhole present within this detention pond, but yet you see nothing about a sinkhole on the original construction plans that were singed off on just a few months later."

The homeowners filed a public records request to build their case against Ben Testerman Construction Company, Ben Testerman, Knox TL Lot Acquisition, LLC, TTBS Development, LLC, and The Glen at Hardin Valley Homeowners Association.

"You know what, the truth is I'm in the insurance business, we live in Tennessee, there are sinkholes everywhere. You may not realize this, but when you know about one, there is a certain responsibility that the developer has to notify people," said Kohler, who is a local insurance agent. "Thankfully, I have sinkhole coverage. But it's frustrating, it's scary, and truth be told, we would really love to get to the bottom of it."

10News contacted the neighborhood's home owner's association, which said "there is no sinkhole," and asked us to contact their lawyer, who did not return our call.

10News also reached out to Ben Testerman Construction Company, where the receptionist refused to reach out to Testerman since he was "out of town."

"He sold us our homes. And our family believes he knew about the sinkhole and didn't tell us," said Gilbert. "We are extremely frustrated."

Just feet from where drillers were performing the boring stands a playground set in Gilbert's backyard.

"We expect to have data in the next few days from the geotech firm," said Gilbert. "And if anyone would like to purchase our home, it's for sale," he laughed.

Kohler said she doesn't expect anyone to be interested in buying the homes.

"If you want to buy, by all means," laughed Kohler. "But seriously, it's been a really frustrating thing for us as homeowners. With large investments in these homes and for the safety of our families, this is important. We need to be heard."