Groundwater contaminated with hexavalent chromium is flowing north off the Electro-Plating Services site toward I-696, where people first spotted the so-called "green ooze."
Officials had to find out if the contamination was also moving south, toward a residential neighborhood.
Preliminary test results show that is not happening. Test results also suggest the contaminated water moving northward has not contaminated the drinking water of towns that draw water from Lake St. Clair, downstream of the property.
The Michigan Department of Environment, Great Lakes and Energy says tests done by two of those cities (Grosse Pointe Farms and Wyandotte) show hexavalent chromium levels are a thousand times lower than the federal standard.