sites along the Grand Calumet. Approximately 90% of the flow of the Grand Calumet consists of industrial and municipal effluent. The portion of the Grand Calumet within Indiana has been designated a
Great Lakes Areas of Concern (AoC) under the Great Lakes Water Quality Agreement, one of 43 sites favored with such a designation. The Grand Calumet has been listed as one of the 43 AoCs since 1986. AoCs are designated by having an impairment in at least one of fourteen
beneficial uses. The Grand Calumet is the only AoC to be impaired on all fourteen. These impairments include total fish consumption restrictions, beach closings, fish
tumors or deformities, animal deformities or reproductive problems, and loss or degradation of fish and wildlife habitat,
benthos,
phytoplankton, and
zooplankton populations, among others. As of 2015, a major dredging project was under way to remove several hundred thousand tons of toxic sediment from the bottom of the Grand Calumet. The dredging was expected to be complete in 2016. and
heavy metals, such as
mercury,
cadmium,
chromium and
lead. Additional problems include high
fecal coliform bacteria levels,
biochemical oxygen demand (BOD) and suspended solids, oil and grease. These contaminants originate from both point and
nonpoint sources.
Nonpoint sources • Contaminated sediment: The Grand Calumet River and Indiana Harbor and Canal contain 5 to 10 million cubic yards (3.9 to 7.7 million m3) of contaminated sediment up to deep. Contaminants include toxic compounds (e.g., PAHs, PCBs and heavy metals) and conventional pollutants (e.g., phosphorus, nitrogen, iron, magnesium, volatile solids, oil and grease). • Industrial waste site runoff: Stormwater runoff and
leachate from 11 of 38 waste disposal and storage sites in the AoC, located within of the river, are degrading the water quality. Contaminants include oil, heavy metals, arsenic, PCBs, PAHs and lead. •
Superfund sites: There are 52 sites in the AoC listed in the federal Comprehensive Environmental Response Compensation and Liability Act (CERCLA) System, more commonly known as Superfund. Five of these sites are on the National Priorities List. • Hazardous waste sites under
RCRA: There are 423 hazardous waste sites in the AoC regulated under the Resource Conservation and Recovery Act (RCRA), such as landfills or surface impoundments, where hazardous waste is disposed. Twenty-two of these sites are treatment, storage and disposal facilities. • Underground storage tanks (USTs): There are more than 460 underground storage tanks in the AoC. More than 150 leaking tank reports have been filed for the Lake County section of the AoC since mid-1987. • Atmospheric deposition: Atmospheric deposition of toxic substances from fossil fuel burning, waste incineration and evaporation enter the AoC through direct contact with water, surface water runoff and leaching of accumulated materials deposited on land. Toxins from this source include dioxins, PCBs, insecticides and heavy metals. •
Urban runoff: Rain water passing over paved urban areas washes grease, oil and toxic organics such as PCBs and PAHs into the surface waters. • Contaminated
groundwater: Groundwater contaminated with organic compounds, heavy metals and petroleum products contaminates surface waters. The
U.S. Environmental Protection Agency estimates that at least 16.8 million US gallons (64,000 m3) of oil float on top of groundwater beneath the AoC.
Point sources of contaminants • Industrial and Municipal Wastewater Discharges: Three steel manufacturers contribute 90 percent of industrial
point source discharges to river. One chemical manufacturer also discharges into the river. Permitted discharges include
arsenic, cadmium,
cyanide,
copper, chromium, lead and mercury. Three municipal treatment works (Gary, Hammond and East Chicago Sanitary Districts) discharge treated domestic and industrial wastewater. •
Combined Sewer Overflows (CSOs): Fifteen CSOs contribute untreated municipal waste, including conventional and toxic pollutants, to the river. Annually, CSO outfalls discharge an estimated 11 billion US gallons (42,000,000 m3) of raw wastewater into the harbor and river. Approximately 57% of the annual CSO volume is discharged within of Lake Michigan, resulting in nearshore fecal coliform contamination. ==Watershed==