Stomping the Dust in the Antelope Valley
The following is a draft version of Stomping the Dust in the Antelope Valley (Paper #O5-A-523-AWMA)
ABSTRACT
The arid desert of the southwestern United States experiences frequent dust problems which can lead to PM10 violations. Blowing dust is one of the major air quality problems of the arid desert. From 1992 through the present, a group of research scientists have been investigating a variety of techniques for mitigating the windblown dust in the Mojave Desert and more specifically the Antelope Valley near Palmdale and Lancaster, CA. This paper summarizes the progress made toward dust suppression in the Antelope Valley during the Calendar year 2004, which corresponds to the seventh and final year of Phase III of this program.
In this ongoing program, the objectives have been broadened to include mitigating dust from all types of disturbed lands, not only abandoned farmlands. Techniques include new approaches to revegetation using plant seedlings, varying water treatments and soil amendments. In 2002-2003, we began a program to use specific cover crops to suppress fugitive dust and soil borne pathogens on irrigated fallow cropland. An array of environmentally friendly chemical and physical suppressants is also being evaluated for cost-effectiveness as a function of longevity. We concluded the field evaluation in late 2003. During 2004, we evaluated our 5-year field evaluation program. Wind fences have been erected in blow sand areas and are being evaluated for longevity and overall effectiveness in reducing dust. Recognizing that barren blow sand areas have the potential to create a domino-like effect of large-scale erosion, during 2002-2003 we initiated a 2-3 year study to quantify the amount of sand eroding from these areas during saltating windstorms. We have also begun a study to identify these potential blow sand areas using continuously updated satellite photos in combination with sophisticated GIS mapping programs.
This paper provides a progress report of our current activities during 2004. This current phase of this research program will conclude at the end of 2004. The end product of this decade-long research will be a practical how-to "cookbook" of dust mitigation solutions for a variety of problem areas. This publication will be geared for various users including regulatory agencies, the USDA NRCS, farmers, construction interests and industry. Already, dust mitigation measures resulting from this 10-year program are being successfully implemented in the Antelope Valley and elsewhere.
INTRODUCTION
During the prolonged CA drought from 1985 to 1992, the metropolitan area of Lancaster and Palmdale and the unincorporated area of Antelope Acres were inundated with wind-blown fugitive dust and fine particulate matter emitted from disturbed upwind areas of the western Antelope Valley. The blowing dust worsened each year with one of the worst episodes occurring in 1991 with a 24-hour recorded PM10 concentration of 780 μg/m3. In response to the increasing severity of wind-blown dust and persistent particulate air quality violations, a locally based multi-agency working group, the DustBusters Taskforce, was organized and convened to formulate strategies.
The taskforce consists of local farmers as well as city and county government representatives. A technical steering committee was formed to address the research issues of dust mitigation in the Antelope Valley. This committee consists of representatives from academia, the California Air Resources Board, the South Coast Air Quality Management District, the Mojave Desert AQMD, the Antelope Valley AQMD, the USDA Natural Resources Conservation Service, the Antelope Valley Resource Conservation District, the City of Los Angeles Department of World Airports, the University of California cooperative extension farm advisor and the Southern California Edison Company.
Beginning in 1998, we began a new phase of dust mitigation research in the Antelope Valley, and expanded the scope to include the stabilization of a variety of disturbed soils. For example, one of the worst culprits is barren land created by summer brush fires. In this paper, we discuss the various approaches we are using to stabilize these disturbed and eroding lands. Topics covered include:
1) evaluation of native seedlings transplanted beginning in January 1999.
2) final evaluation of approximately 20 chemical suppressant plots.
3) identifying, instrumenting and evaluating blow sand sites.
4) meteorological measurements in support of these field activities.
REFERENCES
1. Farber, R.J.; Kim, B.M.; Zink, T.; Janssen, J.; Pietsch, J.; Cowherd, C.; Grelinger, M.A.; Campbell, R.; Nguyen, P.; Lofreso, C.; Almaraz, R.; Lee, J.; DeSalvio, A.; Grantz, D.A.; VanCuren, A.; Huang, A.; Roberts, E.; Poole, G. “Stomping the Dust in the Antelope Valley,” In 97th Annual Meeting of the Air and Waste Management Association, Indianapolis, IN., June 2004 Paper #04-A-386-AWMA. A&WMA, Pittsburgh, PA.