More chemical contamination reportedly has been found in a shallow aquifer under a park in Ann Arbor, Mich., but officials say residents face no health threat.
Similar contamination was found in a nearby fishing lake but at lower levels, reports the Ann Arbor News.
The findings were made during an underground water cleanup by Pall Corp. and have left environmental officials both surprised and puzzled, the report said.
The aquifer contamination was detected in a new well drilled recently and the report said that at a depth of about 40 feet, levels of 1.4-dioxane reached 5,178 parts per billion. The state's cleanup level for dioxane, classified as a probable human carcinogen, is 85 parts per billion.
An expert on environmental engineering for Pall said it's not unusual to find small pockets of high-level contamination. He said results from other nearby wells showed much lower levels, suggesting that it was a very small area of contamination.
Copyright 2006 by United Press International
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