Industrial pollutants beneath the East Isthmus have been blamed for the contamination of the city's Well No. 3, which the Madison Water Utility plans to abandon. Now, a consultant hired by the utility to site a new well has warned that the history of contamination on the Isthmus will make finding a clean source of water in the area very difficult.
Getting rid of these contaminants is difficult, even with the most modern technologies, both because the pollutants are so pervasive and because the plumes of chemicals, especially old industrial chemicals, are hard to find.
About all the city can do with its closed landfills, for example, is monitor pollutants and wait for time to pass.
Cleanup and monitoring of closed city landfills has been expensive and the landfills are likely to need monitoring for years to come. The city has spent more than $35 million since 1999 to clean up the six major landfills it has operated.
As more urban sites are developed into condominiums and commercial property, developers are often faced with cleaning up extensive contamination from old factories that previously occupied the land.
Before McGrath Associates could proceed with development of its Union Corners project on East Washington Avenue, for example, a total of 60,368 tons of contaminated soil was removed from the former site of a Rayovac battery factory, according to records from the state Department of Natural Resources.
Other sources of underground pollution include old buried gasoline and petroleum tanks and the former sites of dry cleaning businesses.
The extent of the threats from such contamination sources is extensive; the DNR in its database of contaminated sites lists 2,250 such sites in Madison, including 783 that are cited as being "open" or still being cleaned up.
It was a dump
Many cities are dealing with underground contamination but in Madison the problems left us by old landfills have been magnified because of the city's geography.
Even such a glittering landmark as the Monona Terrace sits atop garbage. Between 1946 and 1951, the lakeshore from which Monona Terrace now rises, part of Law Park, was a dump where trash from Downtown was simply shoved into the lake.
The building rests on 1,750 steel pilings that were driven down through the compacted trash to the gravel and rock lake bed.
Throughout Madison's history, and especially before the onset of environmental awareness and laws in the 1970s, residents dumped waste in just about every corner of the city, from the mouth of Wingra Creek in Olin Park to the banks of the Yahara River, the river itself and lakeshores such as University Bay.
"The history of this," said city engineer and waste expert Dave Benzschawel, "was that whatever it is, it goes in the closest hole."
The city has operated six licensed landfills over the years. The last, Greentree Landfill on the West Side, closed in the 1980s.
Larry Nelson, Madison's city engineer, said the belief then was that you could simply cover up the landfills and build parks on top of them.
That all changed in November 1983 when methane gas, generated by the compressed and decomposing garbage in the closed Greentree Landfill, leaked into the basement of an adjacent apartment building.
When one of the residents lit a pipe, the gas exploded, severely burning two people, destroying the building and rattling windows for blocks.
In the months and years after that explosion, according to Nelson, the city embarked on an effort to study and control not only the methane gas but also the groundwater pollutants being produced by the chemical reactions inside the buried landfills.
Vented into the air
In the late 1980s, studies showed the landfills were already generating pollutants that were showing up in the groundwater.
Levels of contaminants exceeded health standards in numerous instances, according to city documents from the time, meaning that the city was required by new state landfill laws to conduct a more complete cleanup of the landfills.
That cleanup continues today.
Each of the six landfills is outfitted with gas extraction systems as well as leachate collection systems that capture polluted runoff.
Landfill gases are vented into the air and the contaminated water is drained into the city's sanitary sewers and treated at the sewage treatment plant.
A monitoring and alarm station in the city's public works building on Emil Street, linked by a wireless communication system to the landfills, alerts city workers if machinery malfunctions or gas levels become too high.
The cost of this continuing vigilance is high.
Nelson said cleaning up and monitoring the landfills has so far cost more than $35.2 million. Of that amount, about $25.2 million has been raised through fees collected on water utility bills.
Also, negotiations with companies that disposed of wastes in the landfills resulted in payments from at least two - $430,000 from Madison Gas & Electric and $300,000 from Giddings and Lewis.
City attorney Jim Voss said the law allows the city to pursue claims from private companies that used the landfills to help offset the costs of cleanup. Such companies are considered "potentially responsible parties," Voss said.
Modern waste
While the pollution controls appear to be keeping most contamination from spreading, the landfills still produce high levels of potentially dangerous toxins.
Levels of numerous pollutants have exceeded both state and federal standards at all of the landfills.
At the Sycamore Landfill, 4601 Sycamore Road, the groundwater levels of several carcinogenic chemicals, such as tetrachloroethylene and trichloroethylene, exceed the enforcement standards set by the state and federal Environmental Protection Agency.
Levels beyond the enforcement standard require the city to take actions that reduce the pollutants.
Joe DeMorett, a hydrogeologist for the city, said the pollutants at Sycamore reflect the more modern waste that went into the site - plastics and household cleaning solutions, for example.
So far, the landfills have not been directly implicated in the pollution of any nearby public drinking water wells, though they are often high on the list of suspected sources when problems arise.
And pollutants similar to those found in landfills have been detected in some wells.
Demetral Field Landfill, now the site of a park and athletic fields on Packers Avenue, for example, was suspected as at least one of the potential sources for contaminants that forced Oscar Mayer to abandon a couple of its private wells in recent years. The connection was never firmly made.
There are other problems.
The city has had to buy four homes near the Mineral Point landfill because the homes were damaged when the landfill settled beneath them.
Negotiations are under way to purchase another home that is sinking.
"The landfill is going down and pulling everything with it," Nelson said.
Hard to predict
Buried pollutants plaguing the city aren't likely to go away any time soon. In fact, taking care of the closed landfills is probably going to be a job long into the future.
It is difficult for experts with the city or the DNR to predict how long it will take for pollutants from the landfills to diminish.
Both Nelson and the DNR's Pat McCutcheon, who regulates the city's landfills, said we have reached the limits of the pollution cleanup technologies.
Now, it is just a matter of waiting for the natural decomposition processes inside the landfills to run their course. That can take years, as can the movement of resulting pollutants through the ground.
"I don't see too many opportunities to redevelop the landfills," Nelson said. "Instead, I see the need for continued watchfulness and maintenance. And that's really, really unfortunate. We're stuck."
Only one source
But the landfills are just one source of underground pollution in Madison.
Demolished or abandoned factories, underground gasoline storage tanks from long-gone service stations and the sites of closed dry-cleaning businesses all contribute to a potentially dangerous mix of chemicals that lace the soil beneath the city and sometimes work their way into our drinking water supplies.
One of the most frustrating aspects of this history and the resulting pollution is that it is frequently hidden until a contaminant shows up in a well.
In fact, in its proposal to help the Madison Water Utility find a site for a well to replace the contaminated Well No. 3, consultant Montgomery Associates warned that the biggest problems may be posed by contamination sources that are not identified in any database.
"This is coming back to haunt everybody," said the firm's Robert Montgomery of the long history of careless waste disposal. "And groundwater moves very slowly so we may not see some impacts for decades."
17 contaminants
In 2003, high levels of carbon tetrachloride, an industrial carcinogen, in Well No. 3 on the East Isthmus prompted the DNR to begin an investigation of the pollution and its source.
Within just a quarter mile of the well, McCutcheon - whose job includes investigating sources of contamination - found nearly a dozen sites that had a history of contamination including a railroad yard, a city of Madison garage and waste oil recovery site, a couple of auto repair shops and paint and machine shops. Leaking underground storage tanks were found on at least six of these sites.
In his investigation, McCutcheon zeroed in on the site of an old paint factory, Lindsay Finishes. There had been previous detections of carbon tetrachloride on the property at 1902 E. Johnson St.
McCutcheon sampled the soil and found 17 different industrial contaminants, including carbon tetrachloride.
As he frequently does when he is tracking pollution through time, McCutcheon found a former employee of the now-closed paint factory, a 77-year- old man who had worked at the factory for about 18 years, starting in 1946.
The employee recalled that coal and coal ash were dumped by wheelbarrow on the ground behind the plant and that liquids from the factory were dumped directly on top of the ash piles. The worker recalled that the factory used both carbon tetrachloride and trichloroethylene as degreasers on equipment.
In the end, McCutcheon concluded that the industrial contaminants found at the site of the old paint factory may indeed have been the source of pollutants found in both the deep and shallow aquifer from which the nearby city well pumped drinking water. But the findings, he added, were not conclusive.
The widespread presence of underground pollutants in so many locations on the Isthmus are indications, McCutcheon said, that the legacy of buried contaminants will be with us for many years.
"When I retire," McCutcheon said, "there is going to be plenty of work for those who come after me."
Much of the Isthmus was once low-lying marsh and it has been filled in piecemeal over the years with everything from foundry sand to coal ash and cinders to trash. In more recent years the trash has included plastics, solvents and other modern-day compounds that break down into cancer-causing chemicals.
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