Illinois
Fertilizer Conference Proceedings
January 28-30, 1991
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James F. Frank1
Andrews Environmental Engineering, Inca (AEEI) has recently completed two projects involving the characterization, excavation, and land application of herbicidecontaminated soils at Illinois Agrichemical Facilities. This paper describes the two projects in terms of goals, materials handling, equipment used, regulatory approvals, and cost.
A retail agrichemical facility that had been in operation for over 25 years was considering selling the business. AEEI was hired to perform an environmental property audit at the site. The results of this audit revealed the presence of several herbicides at elevated levels in the soil and groundwater. A hydrogeological study is in progress that will define the nature and extent of the contaminant plume. Ongoing study and remediation efforts are being conducted under (Illinois Environmental Protection Agency) IEPAIs voluntary cleanup program. The soil spreading was conducted under the approval of Illinois Department of Agriculture (IDOA). Plans are proceeding to clean the groundwater by spray irrigation on cropland. The majority of soil remediation has been completed by spreading on cropland.
Five herbicides were analyzed in all soils, they were alachlor, atrazine, cyanazine, metolachlor, and trifluralin. Each herbicide was detected in at least one sample, with the highest concentration being atrazine at 27 ppm. The excavated areas ranged in depth from 6 inches to 24 inches. The soil consisted of a dark loam topsoil.
Soil was excavated by a track hoe and loaded directly into three tandem axle dump trucks. The trucks hauled the soil four miles to the farm field. The loads were scaled to determine actual tons of soil applied. The loads were dumped at one end of the application field in three separate piles. The piles were segregated by the five areas of excavation; each had different levels of contamination. The soil was then loaded onto two John Deere manure spreaders and spread on a designated area of the field. The field had been in a corn-soybean rotation and was going back to corn the following year.
The amount of soil that could have been applied per acre, per the label rate, ranged from a high of 366 tons per acre to a low of 81 tons per acre. From a practical standpoint, 65 tons per acre is the maximum that can be applied using a single pass with a manure spreader. The single-axle spreader hauled 3 tons per trip and the tandem-axle spreader hauled 5 tons per trip. A round trip with a spreader took 12 minutes. A total of 852 tons of soil was spread on 13 acres of cropland.
Some of the contaminated area that was excavated was covered with limestone rock. Since this material was not suitable 'to be spread on a farm field, it was decided to apply the rock to permanent travel lanes that were located between farm fields. The rock was stockpiled and later spread on the lane with a front end loader, tractor mounted blade and a road grader. The rate of rock application was 51 tons per acre. A 12-foot wide field road, 1.8 miles long was covered with rock. The rock application was designed to apply a land application rate of the most limiting herbicide.
The application rates for soil and rock were determined by selecting the herbicide that was the most limiting in terms of concentration of the herbicide and allowed label rate for the next year's target crop. Following is an example of a calculation for a soil contaminated with Atrazine at 16 ppm.
The most limiting herbicide in soil sampling Area A in the surface is atrazine at 16.0 ppm. The broadcast rate for atrazine is 6 pints per acre for broadleaf and grass weed control in corn. Atrazine contains 4 pounds of active ingredient per gallon. The total amount of soil to be removed is 900 tons. This can be spread on 9.6 acres of land.
The loading and transportation operation was accomplished in 2 1/2 days. The spreading of the soil took 3 1/2 days. Estimated cost for soil and rock excavation, transportation and spreading is $8.50 per ton. Cost of preparing the application to the Illinois Department of Agriculture is $3,000 and cost of on-site supervision of excavation and spreading by the engineering firm is $700 per day. For a 2 1/2 day job, the total cost per ton would be $13.28. This cost does not include engineering and laboratory cost to determine the amount of soil that needs to be removed ($2,500) land use rent, or backfill material. Total cost will vary depending on the number of tons involved in the job. Certain costs are fixed irrespective of the volume of soil. Therefore, as more tons are handled, the unit price per ton decreases.
The total cost per ton will probably fall within a range of $18 to $23 per ton including site assessment, laboratory, engineering, equipment rental, land use, and labor costs. This cost range assumes that the agrichemical dealer utilizes some of his own labor and equipment and charges a fair price for the use.
An agrichemical dealership experienced a warehouse fire. Testing of on site soils subsequent to the fire showed soil contamination in three separate areas of the property: a load out area, a surface water ditch and adjacent to two poly tanks that were destroyed in the fire. The management of the company hired AEEI to assess the site soils and obtain regulatory approvals, as necessary, from the Illinois Department of Agriculture (IDOA) and Illinois Environmental Protection Agency (IEPA) for the implementation of a soil remediation project. Six herbicides were analyzed in all site soils: alachlor, atrazine, cyanazine, metolachlor, pendimethalin, and trifluralin. Pendimethalin was not detected. The highest concentration of all herbicides detected was alachlor at 56 ppm. The total volume of soil removed and spread was 518 tons. The fine-grained sand soil was excavated with a track hoe and loaded directly onto four semi-trailers. The soil was hauled 12 miles one way and stockpiled in three separate areas of the farm field, according to its herbicide concentration.
The soil was loaded by a rubber-tired industrial loader into two high flotation trucks fitted with lime spreader boxes. The application rate ranged from a high of 37.5 tons per acre to a low of 60.5 tons per acre. The 517.5 tons of soil were spread on 49 acres. The lime spreader performed very well in providing a uniform application of the sand. It is doubtful that a lime spreader would work properly on loam or clay soils, especially if they were wet or clumpy.
On July 13, 1990, House Bill 3649 was signed into law. At Chapter 5, paragraph 819, Section 19, the following new provisions were created:
"As part of the consideration of cost effective technologies pursuant to subsection 8 of this Section, the Department may, upon request, provide a written authorization to the owner or operator of an agrichemical facility for land application of pesticide contaminated soils at agronomic rates. Such authorization shall prescribe appropriate operational control practices to protect the site of application and shall identify the site or sites where such land application will take place. No authorizations may be provided by the Department after July 1, 1992. The Department shall periodically advise the Interagency Committee regarding the issuance of such authorization and the status of compliance at the application sites."
AEEI has completed work on the first project authorized under House Bill 3649 and has nearly completed the second project. AEEI is currently preparing several additional applications for IDOA approval. Prior to issuance of a letter of authorization to land apply herbicide-contaminated soil, IDOA requires an application to be filed. The application must contain a signature page including: the identification and signature of the agrichemical facility generating the soil, the owner of the land application area and the company name and individual of the author of the plan.
Additional items to be included in the plan are:
A site map;
Plat map of the site and application fields;
A USGS Quadrangle Map;
A soil map of the land application area
Travel route map for soil hauling;
A sampling plan for the site;
Herbicide concentrations detected in soils and rock;
Laboratory analytical reports;
Mathematical calculations on application rates;
An implementation plan detailing work to be performed; and
Concentration of herbicides in the receiving field.
Once the authorization from IDOA has been received, the project may proceed. IDOA requires that one year after application, a final report be filed detailing the concentration of herbicide remaining in the soil of the application field. In addition, a description of the project as implemented is to be included in the close out report. The authority for land spreading projects terminates on June 30, 1992.
AEEI recommends that sampling of the base of the excavated area occur in order to document the cleanliness of the soil left in the excavation. It is desirable to leave the excavation open until the laboratory results are reported, so that additional soil can be removed if necessary. IDOA does not Set clean up levels for soils. Its responsibility under House Bill 3649 is to "prescribe operational control practices to protect the site of application." The site operator is responsible for determining how much soil to remove.
AEEI recommends that backfill soils be carefully selected and tested for adequacy of compaction. If improper backfill materials are selected or inadequate compaction is performed, secondary containment systems could fail.
The agrichemical industry has a unique, time-limited opportunity to perform low-cost cleanups at facilities. Based on many environmental property audits conducted by AEEI, most agrichemical facilities have some herbicide-contaminated soil present on their facility. The soil needs to be removed prior to construction of new buildings, or prior to sale or mergers of businesses. Removing the contaminated soil reduces the chances that groundwater beneath the facility will become contaminated. If the soil were removed and disposed in a landfill, it would be characterized as a special waste. Costs for excavation, transportation, disposal, and regulatory approvals for special waste, range from $60 to $80 per ton. In addition, the facility assumes long-term liability for that waste in the landfill should the landfill ever leak.
The first two projects implemented by AEEI have gone relatively smoothly. The herbicides will be nearly degraded, as they are designed to be, by next spring's planting season, instead of in a landfill where they will not degrade at all. This technology provides the best approach to reasonable cost remediation that is much needed at Illinois Agrichemical Facilities. At the end of two years, it is hoped that the state will evaluate the projects that have been implemented, and make this technology permanently available to the industry.
