MPC
Research Projects (1999-00)

Identifying Number

MPC-176

Project Title

Road Dust Suppression: Effect on Maintenance, Stability, Safety and the Environment

University

Colorado State University

Project Investigator

Dr. Thomas G. Sanders
Department of Civil Engineering
Colorado State University
(970)491-5448 or Fax (970)491-7727
tgs@engr.colostate.edu

External Project Contact

Dale Miller
Larimer County

Project Objective

The objectives are to continue research started several years ago establishing the cost effectiveness of using chemical dust suppressants to increase the time between routine road maintenance on low-volume dirt roads, determine the effect of road dust suppressants on the stability of a road base before and after chip and sealing and to assess the environmental and safety impacts of using road dust suppressants.

Project Abstract

This research project will be a joint cooperative effort with the Larimer County Road and Bridge division and Roadbind America Inc.. Several one mile sections of dirt roads in Larimer County will be used as test and control sections of the research. One or more test sections will be treated with chemical road dust suppressants and the other will remain untreated. More than one road dust suppressant beside Roadbind America Inc.'s lignosulfanate suppressant may be tested if other venders are found who are willing to participate in the research. The county will provide all the labor and equipment for the preparation of the test sections and Roadbind American Inc. will provide the dust suppressant. The Colorado State University Dustometer, developed in previous research supported by the Mountain-Plains Consortium, will be used to quantify the amounts of dust released into the air from all the test and control sections. Measurements of drivability will be defined and measured (examples of drivability are breaking distance and vibrations). A record of all accidents on the roads will be kept during the research duration. In addition, Larimer County records will be investigated to see if there is relationship of the number of accidents (and fatalities) and the type of road treatment (or lack thereof) on the dirt roads. More than one county in the State may be investigated if better records are available.

Task Descriptions

• Task 1 – Find and prepare a dirt road in Larimer County which will be chipped and sealed in the next few years to be used in the tests. This will be done in the spring so that tests can be made during the summer. (Larimer County & T. Sanders, March 2000).
• Task 2 – Apply the road dust suppressants to the one mile test sections and prepare the untreated control section exactly the same way except no chemical treatment. Measure at least 5 cross sections of each of the test sections. Install vehicle counters. (Larimer County - April 2000).
• Task 3 – Make four dust measurements per section per day once a week until a second treatment of the suppressants using the Colorado State University Dustometer. In addition drivability measures will be made on each test section. (T. Sanders - May-November 2000)
• Task 4 – Re-grade the test sections without additional material and measure the same cross sections measured prior to the start of the tests. Apply the second treatment of suppressants. (Larimer County - Summer 2000).
• Task 5 – Keep records of all road accidents during the duration of the tests and investigate county records for a relationship of road accidents and road treatments.(T. Sanders - Project beginning -completion).
• Task 6 – Chip and seal test sections and the control section. (Larimer County - Fall 2000)
• Task 7 – Measure periodically the particulate emanation from all the road sections using the Colorado State University Dustometer. This will require additional support beyond the first year. (T. Sanders - Fall 2000)
• Task 8 – After a review and analysis of the data generated in the research thus far an interim letter report will be prepared and made available to all interested parties and with the permission of the Mountain-Plains Consortium it will be made available on the World Wide Web. (T. Sanders - December 2000).

Milestones, Dates

• Starting Date: November 1, 1999
• Project Milestones: See above Action Items and time table
• Interim Letter Report: December 2000
• Ending Date: December 2000

A continuation proposal will be submitted in the next MPC annual proposal process at about the same funding level indicated in this proposal. A thesis and a MPC report are planned in year 2 if the project is continued.

Yearly and Total Budget

First year: $29,594
Expected Second year: $29,000

Student Involvement (e.g. Thesis, Assistantships, Paid Employment)

Funds are included for support of a graduate research assistant and for an hourly student. An M.S. Thesis or a PhD Dissertation will result from this research.

Relationship to Other Research Projects

This research project is the continuation of a previously funded project in 1993 and 1994 by the Mountain-Plains Consortium assessing the effectiveness of various road dust suppressants. In addition, the Colorado State University Dustometer, an inexpensive dust-measuring device was developed in the project as well. This research will also complement the past MPC supported research conducted by Birst and Hough on chemical additive usage on unpaved roads in the mountain plains states. Since this work summarized a survey regarding the use of chemical dust control/soil stabilizers by county engineers in the six Mountain-Plain states, the results will be very helpful in the selection of suppressants to be used in this project and as source for qualitative assessments of the effectiveness of the different chemicals.

Technology Transfer Activities

The most likely beneficiaries are all the county road departments in the USA responsible for the maintenance of dirt roads.

Potential Benefits of the Project

Potential benefits of the research may change the way the majority of the low-volume dirt roads in the United States as well around the world are maintained. Previous research at CSU has shown that it is cost effective to use dust suppressants on roads having ADTs greater that 100-120 in Colorado. It is expected that a road treated with road dust suppressants for several years prior to chip and sealing will last longer than those without treatment. If proven true, this may cause a paradigm shift in low-volume dirt road maintenance. In addition the impact to safety and the environment may be sufficient to use dust suppressants on all dirt roads regardless of ADTs. The decrease of the fines in the air will reduce air pollution significantly in the rural and nearby urban environments. Visibility and road stability are improved with the use of dust suppressants, which will decrease road accidents and improve safety. The results of the research will be submitted for publication in major peer review, transportation journals such as the ASCE Journal of Transportation Engineering.

TRB Keywords

Dust suppressants, environment, safety, deferred maintenance, drivability, chip & seal