Federal and State Agencies Target Pollution from Cross Border Commercial Trucks
US Environmental Protection Agency and Arizona Department of Environmental Quality Launch Diesel Emissions Inspection Project
(February 28, 2005 – Nogales, Arizona) - The United States Environmental Protection Agency (USEPA) and the Arizona Department of Environmental Quality (ADEQ) will launch a new three-week pilot program on March 11, 2005 to inspect the exhaust emissions of trucks crossing the US-Mexico border at the Mariposa Port of Entry in Nogales, Arizona. Three technologies, including advanced remote sensing devices (RSDs), will be used to monitor pollution coming from commercial vehicles, identify trucks that are polluting the air, and determine the value of an on-going truck inspection program that reduces such pollution. This is the first time remote sensing technology has been used at any border crossing to study truck emissions.
Four million Mexican trucks enter the United States each year through various port crossings in California, Arizona, New Mexico and Texas; 250,000 trucks enter through the Mariposa-Nogales border crossing alone. Scientific studies at congested US-Mexico border crossings conclude that cross-border truck emissions are creating severe air pollution problems in border communities.1 Officials expect the problem to become increasingly severe and widespread when the North American Free Trade Agreement (NAFTA) is fully implemented. Signed in 1992, NAFTA calls for more open trade between the US and Mexico. Legal battles had put NAFTA on hold; but a Supreme Court decision in 2004 cleared the way for full implementation of the international treaty.
Officials will measure heavy duty diesel emissions by using remote sensing devices developed by Environmental Systems Products Inc. (ESP). “RSDs unobtrusively measure exhaust emissions on the road as motor vehicles pass unimpeded through ultraviolet and infrared beams cast across a roadway. Pioneered by ESP in 1992, RSDs are stationed along road shoulders and instantly analyze motor vehicle exhaust by measuring the amount of light absorbed by the emitted pollutants,” said Niranjan Vescio, ESP’s Remote Sensing General Manager. “RSDs provide a significant advancement over previously used, hand-held technology, which only measures visible particulate emissions and no gases. RSD technology measures each of the regulated gases and is more sensitive to the finer particulate emissionsthat are of great health concern today,” Vescio added. Recently, federal officials promulgated rules regulating fine particulates less than 2.5 microns in size. Officials want to ensure that increased trucking and commerce do not endanger public health by increasing air pollution in communities near the US/Mexico border. This pilot project will help verify the heavy duty remote sensing technology and its use to identify high-emitting trucks. The information gathered will ultimately help policymakers develop a plan to safeguard public health and the environment by identifying and repairing trucks that are polluting the air along the US-Mexico border, affecting communities in both countries, while allowing the free flow of commerce to proceed under NAFTA’s terms.
“The instant drive-by emissions test will be able to measure truck exhaust without having to pull the heavy duty vehicles off the road for a more obtrusive physical inspection. RSDs are the only equipment that can measure virtually every one of the nearly 1400 trucks that pass through the border crossing each day during the Spring peak, without interrupting the important flow of commerce,” said Mariposa-Nogales Port Director James Tong.
Officials will also be using Portable Emissions Monitoring Systems (PEMS) and Opacimeters to measure diesel emissions. PEMS is a suitcase size unit that is physically loaded onto a truck and connected to the vehicle’s exhaust system. PEMS log emissions rates continuously as the truck is driven. PEMS provide gaseous emissions data, do not measure particulates and can only measure one truck at a time. Inspectors expect to measure emissions from two or three trucks each day using this method. Opacimeters measure smoke density, or “blackness”, of the exhaust during random roadside inspections. The truck must be stopped, and an opacimeter placed over a vehicle’s tailpipe or smokestack to get an accurate reading. Inspectors can measure 20-30 trucks each day using opacimeters.
Opacimeters measure visible smoke and particles of soot, identifying only a small percentage of extremely high emitters. RSDs detect invisible smoke and particulate matter below the 2.5 micron regulated standard -- one-thirtieth the size of a human hair. RSDs identify a much larger percentage of polluting trucks. With scientific evidence showing that PM is more dangerous at smaller sizes, officials are increasingly concerned about fine particles and how they could harm public health. Fine PM can lodge deep in the lungs, causing heart and lung disease, strokes, birth defects and cancer.
The Mariposa-Nogales border project will help policy makers understand the source of border pollution and shape their efforts to cost-effectively tackle the problem. The program will assess and recommend various strategies to reduce diesel emissions, helping states to meet the EPA’s new standards for fine PM.. Once the three-week project has been completed, the EPA will have the option of continuing a border monitoring program for up to two years.
