Nobody knows for sure where it came from, but more than 50 homes in Chattanooga are built over a high level of lead in the soil.
A homeowner in the Fort Negley community says it created a serious health problem for her and her husband.
The top 4 feet of soil in Vanessa and Terry Kimbrough's yard is being removed by a Florida contractor.
And it can't happen too soon for them and their family.
VANESSA KIMBROUGH, CALLED IN THE EPA "My husband and I kept getting sick..my husband got sicker than ..I was sick but I was sick over the long-haul. My husband got sick almost immediately."
The Kimbrough's moved into the house in 1993 and eventually discovered years later that there was a high level of lead in the soil.
Ms. Kimbrough says she and her husband stayed in a motel for 5 months two years ago, just to escape the effects of high concentrations of lead.
VANESSA KIMBROUGH "They still don't know for sure where it's coming from. They said it was from industrial plants that were here years ago...but they're not really sure."
The house was built in 1906 , so whatever caused the lead contamination happened before that.
Vanessa called the Tennessee Department of Environment and Conservation in 2011.
They tested and scraped 6 inches of dirt..but the lead level did not go down.
The Federal EPA has been investigating since March, and ordered the dirt removal which started last week.
VANESSA KIMBROUGH "When the Tennessee Lead Action Intervention Program came they gave me all this information ..What should be in the soil...anything over 400 is too much."
The Kimbrough yard has 1200 parts per million of lead.
News 12 has learned that 52 of the 82 properties studied..have enough lead contamination to warrant the same Kind of work being done at the Kimbrough home.
VANESSA KIMBROUGH "I actually tried to start a crusade and let people know when I first found out..cause I couldn't get anybody to listen to me. ..I was going door to door."
Work at the Kimbrough house will be done this week.
A spokesman for the E-P-A did not return our calls for information about the Chattanooga remediation work.
But an E-P-A team has established an office on West Main street.
A local spokesman says the entire lead remediation effort will take about six months.