Staff file photo by Jake Daniels / Workers in 2012 gather up the topsoil in the backyard of The Church on Main. Contractors are digging up the inches of soil in the yards of many homes south of Main Street in an effort to rid the area of any possible lead contamination.

History is never just history — especially with environmental issues. And especially with environmental issues that have long memories and long-lasting effects. Like lead.

Ask the people in at least 1,892 homes in eight Chattanooga neighborhoods across the city's Southside — Cowart Place, Jefferson Heights, Southside Gardens, Richmond, Highland Park, Oak Grove, East Lake and Alton Park.

And, no, this has nothing to do with lead-based paint, discovered years ago to be dangerous and since then, well publicized. This lead-poisoning danger — estimated to cost U.S. taxpayers $113.5 million over the coming decade — is about the land on which these homes sit, the yards in which children play and the soils in which residents garden.

The soil in these neighborhoods was contaminated over the past century from residue generated at more than 60 iron, brass and bronze foundries that operated in Chattanooga for nearly a century, until the 1980s. As Chattanooga spread away from the edge of an often-flooding river — pre-TVA, pre-Chickamauga Dam, pre-environmental regulations and EPA — these foundry sands, the wastes of many manufacturing efforts, were used to build up land against further flooding.

This was the case with the heart of the Southside — Read, Mitchell and Carr streets — once part of a huge rail yard. After the city flooded several times around the turn of the 20th century, clay and fill dirt was moved to part of the rail yard and homes were built there.

Now those streets and many of their homes have become the epicenter of our lead contamination discovery.

Chattanooga's misfortune came under investigation by Tennessee environmental regulators and EPA a decade ago when a resident on Read Avenue — a gardener — showed up in an emergency room with lead poisoning and was hospitalized.

At first, in 2011 and early 2012, just over 80 residential yards along Read Avenue, Mitchell Avenue and Underwood Street (formerly Carr Street) were dug up and the soil replaced by EPA because funding wasn't fully available until more yards were tested and until regulators could assign the sites to the EPA's Superfund National Priorities list in September 2018.

But that was just the tip of our lead iceberg.

By November 2012, environmental investigators had taken 230 soil samples in downtown neighborhoods from Missionary Ridge to St. Elmo and found high lead levels in more than 10% of them. That meant, they said, the possibility of dangerous lead levels in our soil was more widespread.

Since that time, nearly 1,900 yards have been sampled and more will be. For now, 280 have been cleaned up, with EPA contractors removing at least 29,967 tons of contaminated soil — the top 12 to 24 inches of yards identified as having lead-contaminated soil — and replacing it with at least 17,978 cubic yards of clean soil, according to EPA spokesman Jason McDonald and documents about the site on EPA's government website.

McDonald told the Times Free Press that the lead contamination in Chattanooga constitutes one of the agency's most expansive cleanup sites resulting from the use of contaminated foundry sand. He said the factories — most of which are long-since out of business — used the soil as fill dirt and spread it as topsoil long before the lead in that waste was discovered and later regulated by EPA. Despite the fact that the polluters can't be made to pay for the cleanup, the work will cost these property owners nothing. That's the purpose of the Superfund program: To foot the bill if the polluters can't be found and made to pay.

The average cost to clean up each property now stands at about $60,000, and the cleanup is projected to take another eight to 10 years to complete, McDonald said.

This is not Chattanooga's first brush with cleanups associated with the EPA's Superfund National Priorities list. But it is the first that has literally landed on residential doorsteps.

The city's 18-acre Amnicola Dump, used for construction debris disposal from 1970 to 1973, was placed on the list in 1983 because of contaminated debris, groundwater and soil. In 1996, following that cleanup paid for by the polluters, the dump was removed from the Superfund list and now is the site of several businesses.

The second was the five-year, $25 million cleanup of Chattanooga Creek — a massive undertaking to pull toxic coal tar from one of the city's major creeks and a tributary to the Tennessee River. In the mid-1990s, just before declaring a two-mile section of the creek a national Superfund site, EPA called it one of the country's most polluted streams.

For decades in the early- to mid-20th century, Tennessee Products burned coal to make coke, a foundry fuel used in the steel industry. Especially during World War II, when the plant operated 24 hours a day, the company literally ditched its waste excess coal tar into the creek — a common practice at the time. In places, the coal tar lined the creek to a depth of more than eight feet.

In all, 46 toxic waste sites were identified in the floodplain, according to Tennessee Department of Environment and Conservation records. Most of the cleanup was completed by late 2010, much of it on the dime of the polluters. But the site was not delisted (for monitoring purposes) until 2019.

Like politics, all environment is local. EPA's Superfund program helped clean up toxic Chattanooga Creek, Amnicola Dump, and now is working on lead-filled yards in our city.

Thankfully for Chattanooga, regulations are not all bad, huh?