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Soil Remediation
EnviroGroup Limited engineers and scientists have been
developing cost-effective approaches to soil remediation for over two decades. Our
evaluations of background concentrations, source identification skills, statistical
sampling plans, and use of institutional controls have, in many cases, eliminated or
reduced the need for soil remediation. When necessary, we have designed passive, low
cost solutions to soil remediation at hundreds of industrial, commercial, and
residential properties.
Source Identification
- We establish natural and anthropogenic background levels to limit cleanup;
- Fingerprint other sources of metals in soil to allocate responsibility; and
- Establish geographic boundaries for cleanup by air dispersion and deposition modeling
of emissions.
Realistic Action Levels
- EnviroGroup develops site-specific action levels for soil cleanup, based on
realistic exposure assumptions.
- Our leaching models have resulted in soil-to-groundwater pathway action levels
over 1000 times higher than EPA soil screening levels.
- We have successfully used institutional controls and multi-tiered lead
action levels to avoid over-conservative lead cleanup levels.
Low Cost Remediation
- EnviroGroup is experimenting with indigenous microbes to reduce solubility and
bioavailability of metals in soil.
- EnviroGroup uses phosphate amendments, deep-tilling, and a variety of caps to
eliminate the need for soil removal.
- When necessary, we provide stream-lined designs for soil removal, minimizing
quantities and costs.
Soil Remediation Project Descriptions
Globe Smelter, Colorado
EnviroGroup is prime consultant for the $38 million cleanup of an historic lead
smelter, arsenic refinery, cadmium refinery, and specialty metals facility in
Denver, Colorado. One operable unit included sampling and soil remediation at hundreds
of residential and commercial properties. Our forensic studies identified other
sources of lead and arsenic in off-site soils, limiting the extent to residential
soil cleanup. We are experimenting with natural microorganisms to reduce the
bioavailability of metals in sediments and increase action levels. Modeling of
vertical migration of metals allowed us to establish soil action levels orders of
magnitude greater than conservative soil screening levels.
Grant Smelter, Colorado
EnviroGroup is conducting an RI/FS at a former lead smelter site in Colorado, including
evaluation of impacts to soils, groundwater, surface water, and sediment. Under a
separate operable unit, EnviroGroup is representing Asarco at EPA work group meetings,
reviewing and commenting on soil investigation cleanup activities. EnviroGroup
persuaded EPA that elevated arsenic was due to historic pesticide application at
hundreds of residential properties, and not smelter emissions.
Lead Refinery, Nebraska
EnviroGroup is evaluating sources of lead throughout the City of Omaha, based on
the results of EPA removal action sampling and testing of lead paint distributions
around houses by EnviroGroup. Although EPA is attempting to point to lead refinery
emissions as the primary source of lead in soils across the city, our evaluations
are showing that emission impacts are limited and that lead paint is the primary
source. Studies are on going.
Copper Refinery, Washington
EnviroGroup is evaluating sources of arsenic in soils on Vashon-Maury Island near
the former Ruston copper refinery in Tacoma. The forensic study is evaluating extent
of smelter impacts and the contributions of pesticides and other anthropogenic
sources. |
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Services |
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- Background Evaluations
- Source Identification
- Sampling Plans
- Removal & Cap Designs
- Phytoremediation
- Construction QAQC
- Risk Assessment
- Community Relations
- Expert Testimony
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