The Lawrence water supply complies with Environmental Protection Agency standards regarding the level of atrazine, according to a report released by the Lawrence city manager's office.
The report came in response to a letter from Linda Bailey, Lawrence, who said she was concerned that a high level of the herbicide was contaminating the city's drinking water. Bailey wrote to Bob Schumm, city commissioner, requesting that the city study the problem and consider purchasing equipment to filter atrazine out of the water.
The report includes information about EPA regulations, testing for atrazine in the Lawrence water supply, treatment for atrazine and regulation of atrazine use.
According to the report, the EPA set the maximum contaminant level of atrazine in drinking water at three parts per billion (ppb) based on lifetime exposure. The level is based on the average of four quarterly samples.
The Kansas Department of Health and Environment monitors atrazine levels once every three years. The Lawrence utilities department won't test for atrazine until January 1993, but a Kansas University professor and his class recently tested water samples from the Kaw River and Clinton Lake water processing plants between November 1990 and December 1991, the report said.
Based on the data they collected, the report said, "Water treated at the Clinton plant has extremely low levels of atrazine, even in untreated water. Atrazine is a bit more prevalent in the Kansas River.
``During June and July, the level of atrazine in treated water from the Kaw River was 5.66 and 4.10 respectively. However the average atrazine level at the point of distribution from the Kaw Plant was 1.94 ppb over the thirteen month period ..."
The report said higher levels of atrazine are expected in late spring and early summer because of farming practices upstream. However, it stressed that the KDHE and EPA consider the average level of atrazine when measuring against the maximum contamination level.