CHATTANOOGA, TN (WRCB) -- More Southside properties could be affected by dangerous levels of lead. While top soil removal continues at more than 50 residences along Mitchell and Reed Avenues and Carr Street, representatives from the Environmental Protection Agency and the Tennessee Department of Environment Conservation told the Chattanooga City Council, Tuesday, that at least 20 additional problem properties have been identified in other Southside neighborhoods.

Perry Gaughan of the EPA and Troy Keith from TDEC said they still do not know the cause or source of the dangerous levels of lead. They have discovered it is contained in the top 6-10 inches of soil and does not appear to be underneath houses. The tainted topsoil is, however underneath an alley which was paved in the 1960's. Some of the oldest homes were constructed just before 1905. These two dates give them some idea of a span of time when the dirt could have been moved into the area.

The lawns of more then 80 Southside properties were sampled in the current abatement phase. Some 52 were found to contain lead 400 to 900 parts per million with some spiking toward 1,200 PPM. The cut-off for safety in the Southeast is 400 parts per million. Found directly beneath the dark layer of contaminated soil is red clay. Its lead level measures around 60 PPM.

Other areas have been surveyed with at least 20 other problem sites coming to light. Councilwoman Sally Robinson tells Channel 3 the bad soil seems to be confined to a the section of the Southside bordered by Main Street to the ridge and 21st Street to the river. The leaded soil at the additional sites will be taken care of in phase 2 of the Superfund Cleanup lead by the EPA.

Councilwoman Robinson has called a meeting of the Housing and Public Safety Committee for mid-December to keep city leaders and residents fully informed of progress and any potential hazards. The meeting will be set for either 12/11 or 12/18. Stay with for the latest.