The U.S. EPA is recommending that a portion of downtown Ashland's lakefront be declared a Superfund site.  The Ashland site encompasses Northern States Power Company (NSP) property (including the location of a former manufactured gas plant (MGP) that operated from 1885-1947), a Wisconsin Central Limited Railroad corridor, Kreher Park (formerly the location of City of Ashland's waste water treatment plant), and Chequamegon Bay.

The proposed Superfund designation is based on evidence that benzo(a)pyrene, benzo(a)anthracene, xylenes, ethylbenzene, and other VOCs from former MGP operations have contaminated soils and underlying ground water, and have migrated to Chequamegon Bay.

Chequamegon Bay, in Lake Superior, is a recreational fishery and boating area.  A marina is directly adjacent to the site.  The Common Tern, a state endangered species, nests in Chequamegon Bay.  In addition, the Ashland Water Utility, serving 9,115 people, has a water intake pipe in the bay approximately 1,922 feet offshore of the Kreher Park area.

In 1989, the city of Ashland performed an investigation on the Kreher Park area for possible expansion of its existing wastewater treatment facility.  The discovery of contamination from what was believed to be creosote wastes in the subsoils and ground water at Kreher Park prompted the city to abandon the project.

Subsequently, Wisconsin Department of Natural Resources (WDNR) staff performed an assessment of the contamination in 1998.  Soil borings and ground water samples indicated elevated levels of hazardous substances.  WDNR also discovered that Chequamegon Bay sediments directly offshore of Kreher Park contained VOCs, PAHs, and DNAPL oils and tars.  Disturbance of these sediments releases oils and tars to the water column and surface, causing a slick to form on the water surface.

Industrial activities have dominated the lakefront portion of the site for the past 150 years.  Currently, it consists of a landfilled area in the city-owned Kreher Park.  Sawmills operated on the lakefront from the early 1880s through 1931.  The city-owned parcels of the lakefront were created during the late 1880s to the early 1900s by the placement of wood wastes, soil, sand, and demolition wastes into Chequamegon Bay.

During the six decade operation of the MGP, residual coal tars and oils were produced as a by-product from the manufacture of natural gas from coal.  Records indicate that the residual MGP wastes such as coal tar and oils were discharged with the waste water.  On-site fill soils contaminated with coal tar have been found with free product dense non-aqueous phase liquids (DNAPLs) in the base of a former ravine that extends across the NSP facility, indicating that some of the coal tar was disposed on site.

This disposal ravine also contains cinders ash, boiler slag, and demolition debris.  Just north of the ravine is a seep where water, oils and tar flow to the land surface.  Historic drawings refer to a waste tar dump between the seep area and waste water treatment plant.

In 1995 and 1999, NSP conducted investigations that further defined the area of contamination and confirmed the presence of VOCs associated with coal tar wastes.

For more information from the EPA about this site, click here.