EPA/540/MR-99/502

July 1999

United States

Technology Description: EnvirobondTM is a proprietary

process that binds with metals in contaminated soils and

other wastes. Rocky Mountain Remediation Services, L.L.C.

(RMRS), claims that the treatment process effectively

prevents metals leaching and can be used with mechanical

compaction to reduce the overall volume of contaminated

media by 30 to 50 percent. The process is designed to treat

soils in situ, thereby reducing handling, transportation, and

disposal costs associated with secondary wastes generated

by many conventional technologies.

EnvirobondTM consists of a mixture of additives containing

oxygen, sulfur, nitrogen, and phosphorous; each additive has

an affinity for a specific class of metals. RMRS claims that the

EnvirobondTM process converts each metal contaminant

from its leachable form to an insoluble, stable, nonhazardous

metallic complex. RMRS claims that, by effectively binding

the metals, the process reduces the waste stream’s

Resource Conservation and Recovery Act (RCRA) Toxicity

Characteristic Leaching Procedure (TCLP) test results to

less than the RCRA-regulated levels, subsequently reducing

the risks posed to human health and the environment.

Waste Applicability: RMRS claims metals that can be

stabilized with EnvirobondTM include arsenic, barium,

cadmium, chromium, lead, mercury, nickel, selenium, silver,

and zinc. However, the process is less effective in media

containing more than 30 percent by weight of metals such as

aluminum, magnesium, calcium, and manganese. These

metals may reduce the number of chelating sites available by

preferentially binding with the EnvirobondTM agent.

Evaluation Approach: The Ohio Environmental Protection

Agency (Ohio EPA) and U.S. EPA, through a cooperative

agreement, evaluated the EnvirobondTM process at the

Crooksville/Roseville Pottery Area of Concern (CRPAC) in

Roseville, Ohio. The EnvirobondTM process was evaluated

at CRPAC to determine its ability to reduce the amount of

leachable lead in industrial soils and in residential soils,

as determined by the TCLP. EnvirobondTM was concurrently

evaluated for its ability to reduce the relative percent of

bioavailable lead in residential soils by a minimum of 25

percent, as determined by a Physiological-based Extraction

Test (PBET).

The evaluation consisted of treating 10 experimental units in

a residential area, and one experimental unit in an industrial

area. The experimental units in the residential area

measured 5 feet long by 5 feet wide. The experimental unit at

the industrial site measured 6 feet long by 3 feet wide. After

the sod was removed from all of the experimental units, the

contaminated soil was mechanically mixed to a depth of 6

inches. Soil samples were collected before the treatment

process was applied. The experimental units were treated

with EnvirobondTM by applying the proprietary mixture to the

surface of the tilled soil using a fertilizer spreader. The soil pH

was adjusted to approximately 7.0 after the application of

EnvirobondTM, and the experimental unit was tilled.

Some of the experimental units were resampled 24 hours

after application of the EnvirobondTM process for TCLP lead.

The original sod cover was returned to nine of the

experimental units; one residential unit was seeded with

fescue to evaluate whether plant uptake of contaminants

occurs following treatment. Lysimeters were installed to a

depth of 6 inches in one unit at the residential site and in the

unit at the industrial site. The water collected in the lysimeters

will be analyzed on a quarterly basis for lead to evaluate the

long-term effectiveness of the treatment.

Preliminary Results: Results of the pre- and posttreatment TCLP lead analysis from the industrial soils are

presented in Table 1. Results of the TCLP lead analyses for

the residential soils are presented in Table 2. Key findings

from the demonstration, including complete analytical results

and a cost analysis, will be published in a Technology

Capsule and an Innovative Technology Evaluation Report.

Environmental Protection

Agency

Demonstration Bulletin

EnvirobondTM Process

Rocky Mountain Remediation Services
BULK RATE

POSTAGE & FEES PAID

EPA

PERMIT No. G-35

United States

Environmental Protection Agency

Center for Environmental Research Information

Cincinnati, Ohio 45268

Official Business

Penalty for Private Use

$300

EPA/540/MR-99/502

Table 1. TCLP Lead Results in Industrial Soils Table 2. TCLP Lead Results in Residential Soils

For Further Information:

EPA SITE Program:

Ed Barth, Project Manager

U.S. Environmental Protection Agency

Office of Research and Development

National Risk Management Research Laboratory

26 Martin Luther King Drive

Cincinnati, OH 45268

(513) 569-7669; FAX: (513) 569-7571

E-mail: barth.ed@epamail.epa.gov