- About 2,778 homes will need soil excavated over nearly 15 years at a federal cost of almost $113 million, according to a report on the Matthiessen and Hegeler zinc factory Superfund site in La Salle.
The U.S. Environmental Protection Agency’s 399-page report outlines selected plans to clean up contamination in and around the 227-acre Superfund site.
Since at least 2015, when the EPA scheduled public meetings about the cleanup, nearby residents have been concerned about threats to their health, future use of their yards and effects on property values.
To remove high levels or arsenic, lead and cadmium in residential yards, the EPA plans to excavate 200,000 cubic yards of soil.
This would fill about 18,000 dump trucks. The removed soil would be replaced with clean soil and yards would be left looking as they were.
The former zinc smelting grounds east of Sterling and Zinc streets, and the next-door grounds at Carus Chemical Co., including land sloping eastward to the Little Vermilion River, also are targeted for cleanup.
Not even a heads-up?
La Salle officials said they had not been notified of the latest EPA report, which was issued in April.
“I’m not aware of the decision,” said La Salle’s attorney, Jim McPhedran. “To my knowledge, the city was not forwarded a copy.”
La Salle Mayor Jeff Grove, when he heard the estimated number of homes requiring cleanup, said, “Wow, that many?”
Grove said investigation and cleanup is the right direction.
“Whatever we need to do or can do with the EPA, we’re willing to work with them and the Carus family to rectify this. I think it’s a positive that we’re moving in this direction and getting a solution.”
Regulatory agencies have investigated the site for at least 26 years. The latest EPA report does not outline dates and sequences of cleanup but said this will be determined in the next step, the cleanup design phase.
The EPA is considering using phases for residential cleanup, giving higher priority to properties with the highest concentrations of contaminants and posing the greatest health threat.
How many yards will be tested?
The EPA’s current estimate of 2,778 properties comprises about three-fourths of all residences in La Salle, based on the number of homes in the latest city water billing cycle, according to the city of La Salle.
The number of properties that will be cleaned up, and the depth of soil excavation, will be determined in the design phase.
“Since only a small percentage of the residential properties were tested during the remedial investigation, many additional properties remain to be tested,” the EPA report said.
A few Peru residents might get caught up in this. Earlier investigations tested about 200, or 4 percent, of properties over an area that contained about 5,000 residences to the north, south and west of the factory site, stretching roughly to Pulaski Street on the east side of Peru.
The report lists 185 residential addresses that were previously tested, and provides risk and hazard assessments based on test results. To reach the estimate of 2,778, the EPA divided neighborhoods into four zones, based on earlier test results and distances from the former factory site, and extrapolated results to the entire zone.
The cost estimate of $112,925,000 was based on excavating a maximum depth of 24 inches.
“However, the required excavation depth at any given property may be less, based on that property’s sample results,” the report said.
Leave yards as found
After removing contaminated soils and adding cleaning soil, the EPA plans to lay sod, and water and mow yards for 30 days.
“At each residential property, excavated areas will be backfilled with clean soil, including 6 inches of topsoil, to maintain the original grade,” according to the report. “Each yard will be restored as closely as practicable to its pre-remedial action condition. The cost estimate assumed that excavated yards at residential properties would be sodded and that non-residential properties such as schools, parks, commercial/industrial properties, etc., would be seeded. Once the properties are sodded or seeded, maintenance of the sod/seed, including watering, fertilizing, and cutting, will be conducted for 30 days. After the initial 30-day period, property owners will be responsible for the maintenance of their yards.”
How bad are the contaminants?
The contaminants include metals and metalloids such as arsenic, zinc, antimony, cadmium, manganese and lead. In some cases, these are at concentrations that could cause cancer in people exposed continuously over many years and decades, according to the EPA.
The zinc factory area contains the highest levels. Arsenic measured 810 and 528 parts per million. A pile zinc plant waste dumped near the Little Vermilion River has arsenic as high as 251 and 117 parts per million. In residential areas, the highest arsenic concentration was 51.2. The goal is to reduce arsenic to 18 or less in residential areas, according to the report.
The former zinc factory area had lead concentration as high as 209,000 and 62,600 parts per million. Other high measurements of lead include 38,700 in the slag pile, 3,660 on the Carus plant grounds and 3,220 in the residential area. The EPA plans to reduce lead to 400 parts per million or less in neighborhoods, but this goal is being reevaluated and could change, according to the report.
The highest level of cadmium measured in residential areas was 120 parts per million. The goal is to reduce this to 6.4. On the main zinc smelting grounds, cadmium measured 1,020.
Contaminants of concern on the Carus grounds include arsenic, manganese, lead and benzo(a)pyrene.
Scrubbing the industrial footprint
The EPA plans to excavate contaminated soils and consolidate them on the former zinc smelting grounds, although the cleanup design phase will determine if soil needs to be disposed off-site. Excavated soil in this project is considered hazardous waste.
The 180-acre Matthiessen and Hegeler Zinc Co. site was home to zinc smelting and milling from 1858 to 1978, as well as sulfuric acid production, ammonium sulfate fertilizer manufacturing and coal mining. Some earlier emergency cleanups were done. Runoff washes into the Little Vermilion River and river samples indicate elevated levels of metals.
Responsible parties for the zinc factory area include La Salle Acres Inc., which owns about 110 acres, and Fred and Cynthia Carus, who own 17 acres, according to the EPA.
Zinc smelting waste, known as sinter and slag, were dumped on land later purchased by Carus Chemical Co. The largest pile is 80 to 90 feet tall and covers 18 acres.
To the immediate south of the zinc site, Carus Chemical Co. was founded in 1915 by Edward Hegeler Carus, grandson of M&H zinc magnate, Edward Hegeler. A primary product of the company to this day is potassium permanganate. Over time, Carus added production of phosphate corrosion inhibitors, manganese dioxide, sodium permanganate, 2,3-pyridine dicarboxylic acid, manganese-based catalysts, hydroquinone, manganese sulfate and cesium compounds.
Under a 2006 order, Carus Chemical Co agreed to study and clean up its property. Kegan Pakula, Carus Chemical Co. spokeswoman, issued a statement this week regarding the latest EPA report.
“Carus remains committed to working with the EPA throughout this process. The selected remedy is very similar to the proposed remedies already discussed in public forums and in our ongoing communication with the EPA, so there were no surprises when the record of decision was released earlier this year.”
Groundwater
The EPA believes groundwater does not warrant cleanup now or in the future, according to the report.
The zinc smelting did not impact deep bedrock, and shallow groundwater at the site does not connect with the deeper aquifer, and the city obtains its drinking water from four wells about three-fourth of a mile south of the site.
The state classifies groundwater beneath the Superfund site as general resource, not to be used for drinking, and there are no groundwater wells there. Further, a city of La Salle ordinance approved in 2002, in conjunction with the Illinois EPA, prohibits drilling of water wells there, according to the report.
Source: 2,775 homes, $113 million: EPA selects remedy for Superfund cleanup in La Salle. lead contamination epa environmental protection agency