Investigation of Methodologies to Control Dust on County Roads in Western North Dakota (TPD1204023)

BACKGROUND

Due to the increased traffic volumes related to oil development in western North Dakota, dust along the many unpaved roads is causing many complaints to local road superintendents and County Commissioners.  Residents are concerned about poor visibility, damage to vegetation and adverse health effects. County road crews cannot adequately maintain all roads that are impacted as existing treatments can be short lived or require repeated applications. Cost for maintaining roads are increasing and the sources of good aggregate for road surfacing are becoming scarce or are often poorly distributed within each county.

This project proposes to evaluate and compare several different products and construction techniques. Magnesium chloride, flake calcium chloride, acrylic copolymers, synthetic organic oil, petroleum emulsions, crude oil and oil field brine will be used in road test strips of one half to one mile in length. Candidate roads for testing will be selected within Dunn and Mckenzie Counties by county personnel. Roads will be selected based on traffic volumes, road base materials and available aggregate quality.

Where suitable aggregate is not available, aggregate may need to be treated with clay binder to improve its quality.

CURRENT STATUS

An advisory committee was established and met in December to provide advice on project development and assist in the development of the evaluation criteria and review of the test segments.  The committee members are:

Sandy Clark – ND Farm Bureau

Scott Ressler – ND Stockmen’s Assoc.

Dan Wogsland – ND Grain Growers Assoc.

Terry Kovacevich – Marathon Oil

Dale Enerson – ND Farmers Union

Tom Desutter – NDSU Extension Service

Scott Radig – ND Department of Health

Darcy Rosendahl – ND Local Technical Assistance Program (LTAP)

Criteria to evaluate the effectiveness of the dust control products and techniques have been proposed and further work needs to be done to refine the evaluation criteria. County Personnel will be responsible for conducting the evaluations and recording their observations and recommendations.

Attached is a list of the products that were considered for evaluation. Most are commercial products but the list includes products from the oil field as well. The County Engineers and Road Superintendents met in January and reduced the list of products for further consideration to six to eight products to keep the test to a reasonable scope. Some products were not considered for further testing because of prior use, cost or the application process was too time consuming for normal operations. Counties were particularly concerned with the performance of soil stabilization products as they may impede future maintenance by breaking up in large chunks that do not disintegrate with normal maintenance of the road. Final decisions on products to test and test segment locations will be made in April and May.

In conjunction with the ND Department of Transportation Materials Testing Laboratory, several design mixes of crude oil and aggregate from both Dunn and Mckenzie Counties were tested and evaluated. Bakken, Red River and Tyler crude oil samples were provided by the Oil and Gas Division and aggregate from the Nupen and Knutson pits in Dunn County and Lass, Mckenzie North and Mckenzie South pits in Mckenzie County were provided by the Counties. A scoria sample from Dunn County was also provided. The results indicated that a 1% to 2% crude oil by weight mixed with the gravel aggregate controlled visible dust in the laboratory samples. In the scoria, a 3% to 4% crude oil by weight mix was required to achieve the same level of control. The Bakken crude oil was considered less desirable for use because it appears to contain more volatile fractions that quickly evaporate from the aggregate surface. Heavier crude, such as the Tyler, appeared to better coat the aggregate particles but needed to be mixed into the aggregate as it would not penetrate when surface applied.

The samples were then evaluated by the ND Department of Health Laboratory to determine the potential for runoff contamination. The samples were tested using a simulated leaching event and analyzed for diesel range organics. Results indicated that there was less than one milligram per liter of diesel range organics in all samples including the 4% crude oil mixed with the scoria. Field testing will be done this spring to verify the design mixes and application techniques and to check for potential runoff contamination.

Oil field brine water will be applied in mid April to a five mile section of Dunn County road north of Killdeer to evaluate application rates and techniques. Environmental samples will be collected and analyzed by the North Dakota Department of Health Laboratory to evaluate any environmental impacts from the use of this material. Results from the research may be used to modify the Department of Health’s guidelines for the use of oil field brines for dust and ice control.

FUTURE ACTIONS

Current plans are to begin application of the commercial dust control products in May or June. Initially, the Counties wanted to wait until June when the weather is more settled and the spring rush of road maintenance is completed. Because of the mild and dry weather, that schedule is being reevaluated to determine if the tests can begin in May. The crude oil and oil field brine tests will be conducted as soon as locations and materials can be arranged. Tests on the crude oil and oilfield brines may need to be repeated to refine the application techniques and improve the results.

EXPENDITURES

Because contracts were just recently signed, no expenditures have been reimbursed although some expenses have been incurred. It is expected the pace of expenditures will increase significantly over the next several months as the field testing begins.