EVALUATION OF DUST SUPPRESSION PRODUCTS CONDUCTED FOR THE MARINE CORPS AIR GROUND COMBAT CENTER, TWENTYNINE PALME, CA

NAVAL FACILITIES ENGINEERING SERVICE CENTER Port Hueneme, California 93043-4370

Site Specific ReportSSR-2343-ENV

by G. Anguiano R. Sandoval T. Webb November 1997

Distribution authorized to U.S. Government agencies only; test and evaluation; November 1997. Other requests shall be referred to Naval Facilities Engineering Services Center.

Printed on recycled paper

EXECUTIVE SUMMARY

The Marine Corps Air Ground Combat Center (MCAGCC), located at Twentynine Palms, CA, is implementing measures to control dust generated from vehicular traffic on unpaved roadways and other areas of concern. This is in response to the MCAGCC�s recent classification as a moderate non-attainment area for dust particulates, referred to as Particulate Matter (PM10). PM10 is defined as particles with an aerodynamic diameter less than 10 microns. PM10 poses a health risk to humans because these smaller particles can reach the lower regions of the respiratory tract; can effect performance and life of mechanical equipment and may violate the Clean Air Act when present at high levels. Consequently, the Natural Resources Environmental Affairs directorate (NREA) of MCAGCC tasked Naval Facilities Engineering Service Center (NFESC) with the job of recommending a suitable dust suppressant to be used at MCAGCC. As part of this effort NFESC was responsible for identifying reputable and reliable dust suppressants, developing a dust protocol to evaluate these dust suppressants, executing tests to verify effectiveness, and making recommendations. The main objective is to provide MCAGCC with a dust suppressant that will reduce PM10 to levels in compliance with the Clean Air Act. NFESC conducted a site survey and literature search to acquire information required for dust suppression selection as well as to determine a suitable location for product testing and evaluation. Pertinent information included key soil properties such as soil grain size, distribution, and pH. Subsequently, a �Sources Sought� announcement was placed in the Commerce Business Daily to seek information and assess company interest in applying dust suppressants/soil stabilizers on unpaved areas at MCAGCC. Upon receipt of responses from interested companies, NFESC categorized and ranked the products in terms of material and labor cost, and equipment requirements. Based on this comparative analysis, and direction from a decision meeting with NREA, five top ranking products were selected for further evaluation. These products were: Envirotac II, Soil Sement, Asphotac, Dustrol, and Dewatered Residual Wood Fiber. The test protocol consisted of both bench scale and field-testing. Bench scale testing involved the implementation of six test beds; one for an untreated baseline and the others for the five selected products. The primary components of the test beds were the concrete secondary containment systems, a hydraulically powered test wheel, and a dust recovery system consisting of a large industrial blower, lightweight ducting, rotator assembly a shroud cover and an iso-kinetic sampling system. Six concrete secondary containment systems (12�x13�x12�) were pre-fabricated and installed. Each of them was filled with soil, and then treated and integrated with the hydraulically powered test wheel and the dust recovery system. The test wheel spins about the center of the test bed to simulate a vehicle tire rolling over treated soil. The dust recovery system iso-kinetically collects the dust generated from the tire as it passes over the treated soil using Environmental Protection Agency standard Method 5 for particulate mass determination. Part of the test protocol was to provide the same type silty sand soil, and subject the treated soils to the same compaction, subgrade, slope, environmental exposure and wheel loading. Results of bench scale testing executed from February 1997 to July 1997 indicated that polymer

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products, Envirotac II and Soil Sement, generated the least amount of dust under equalized test conditions. Subsequently, these two top performing products were applied on sections of an unpaved roadway, and after 4 hours of curing, the road was opened for traffic. The sections of roadway were visually monitored over a period of several months. Each product suppressed dust when compared to adjacent non-treated roadways, however, some degree of rutting and lifting occurred with each product. Both Envirotac II and Soil Sement performed reasonable well under actual field conditions and are recommended for use in low traffic unpaved surfaces. This report documents the test protocol, test results from both bench scale and field testing, and economic and toxicity analysis.

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Acknowledgment Appreciation is extended to the various individuals whose assistance has made this effort possible. Lieutenant Colonel Reeder, Director, Natural Resources/Environmental Affairs Directorate, MCAGCC Mr. Leon Bowling, Environmental Affairs Officer, Natural Resources/Environmental Affairs Directorate, MCAGCC Mr. Chris Gonzales, Pollution Prevention Manager, Natural Resources/Environmental Affairs Directorate, MCAGCC Mr. Phil Chambers, Air Quality Specialist, Natural Resources/Environmental Affairs Directorate, MCAGCC Chief Warrant Officer (CWO2) Vito Steele, Aviation Ground Support Element, Expeditionary Airfield, MCAGCC Mr. Rich Rossie, Technical Consultant, Aviation Ground Support Element, Expeditionary Airfield, MCAGCC Master Sergeant Hackson, Aviation Ground Support Element, Expeditionary Airfield, MCAGCC Gunnery Sergeant Elliot, Aviation Ground Support Element, Expeditionary Airfield, MCAGCC Gunnery Sergeant Diebert, Heavy Equipment, Expeditionary Airfield, MCAGCC Staff Sergeant Hodge, Heavy Equipment, Expeditionary Airfield, MCAGCC Mr. James Ingrim, Range Operations Training Director, MCAGCC Mr. John Rule, United States Department of Agriculture, Natural Resources Conservation Service Captain Kimbrough, Facilities Maintenance Officer, Facilities Maintenance Department, MCAGCC Mr. William Sims, Operations Officer, Facilities Management Division, MCAGCC Mr. Rey Cuevez, Facilities Maintenance, MCAGCC Mr. Ray Hunter, Pragma, Inc. Sutter Creek, California Mr. John Vermillion, Environmental Products and Applications Co. Inc., Lake Elsinore, California Mr. Jim Weisenberger, Coast Resource Management, Inc., Cerritos, California Mr. Frank Ellswick, Midwest Industrial Supply, Inc., Canton, Ohio, California Ms. Lois D. Anderson, CEO & Managing Director, Anderson Affiliates, Inc., Sugar Land, Texas Mr. Roger Gose, Gose & Associates, Stillwater, Oklahoma Mr. Jack Gillies, Desert Research Institute, Reno, Nevada Ms. Paulette Peterson, Naval Facilities Engineering Command Contracts (NAVFACCO) Naval Construction Battalion Center, Port Hueneme, California From Naval Facilities Engineering Service Center, Port Hueneme, California-Mr. John Comstock, Mr. Robert Miller, Mr. Dave Cook, Mr. Ray Cappillino, Mr. Manuel Perez, Mr. Daniel Polly, Mr. Carlos Garcia, Mr. John Crahan, Mr. John Cornac, Mr. Tanwir Chuandry

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1. INTRODUCTION The Marine Corps Air Ground Combat Center (MCAGCC), located at Twentynine Palms, CA, is implementing measures to control dust generated from vehicular traffic on unpaved roadways and other areas of concern. This is in response to the MCAGCC�s recent classification as a moderate non-attainment area for dust particulates, referred to as Particulate Matter (PM10). PM10 is defined as particles with an aerodynamic diameter less than 10 microns. PM10 poses a health risk to humans; can effect performance and life of mechanical equipment and may violate the Clean Air Act when present at high levels. Consequently, the Natural Resources Environmental Affairs directorate (NREA) of MCAGCC tasked Naval Facilities Engineering Service Center (NFESC) with the job of recommending a suitable dust suppressant to be used at MCAGCC. As part of this effort NFESC was responsible for identifying reputable and reliable dust suppressants, developing a dust protocol to evaluate these dust suppressants, executing tests to verify effectiveness, and making recommendations. The main objective is to provide MCAGCC with a dust suppressant that will reduce PM10 to levels in compliance with the Clean Air Act. An economic analysis will be included as a guide to determine product feasibility. NREA tasked NFESC to develop an unbiased test protocol so that suitable, commercially available, dust suppression/soil stabilizers could be competitively selected. A suitable product is one that provides adequate dust control for the extreme climate, soil, and traffic conditions found on unpaved areas located at �Mainside� and the Expeditionary Airfield (EAF). This report documents the testing and evaluation of various products conducted at MCAGCC, Twentynine Palms, from January 1997 to July 1997. Recommendations are made to guide further use. 1.1 BACKGROUND MCAGCC is located in the high desert and is characterized by hundreds of miles of unpaved roads, unimproved open ranges, and unpaved lots used by personnel and equipment for Combined Armed Exercises (CAX) and routine base functions. Dust is generated by light and heavy duty wheeled and tracked vehicles, foot traffic, as well as impingement by propeller down wash or jet backwash (See Photograph 1). The dust particulates that remain suspended in the air for extended lengths of time are those with aerodynamic diameters less than or equal to a nominal 10 microns, PM10. PM10 is one of six criteria pollutants addressed in the National Ambient Air Quality Standard, Clean Air Act. Scientific studies indicate that dust particulates, especially those under 2.5 microns, can adversely affect human health by entering into alveoli region of the lungs where they can persist and damage the respiratory system. (Future regulations are currently being developed for PM 2.5). In terms of safety, dust clouds can dramatically reduce visibility and create hazardous conditions for pilots and motorists. From a cost standpoint, dust degrades the performance of vehicles, equipment, and aircraft and also reduces the service life of aircraft engines and propellers due to increased friction wear. Studies have also shown that morale and productivity are diminished when personnel are continuously exposed to dusty conditions.

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There are a variety of solutions available for suppressing dust, ranging from intermittent application of water spray to covering trafficked areas with asphalt or concrete. In the private sector, chemical dust suppressants and soil stabilizers are frequently used for both low and moderate traffic areas. Manufactures claim that these products are highly effective and environmentally safe. In addition to developing an unbiased test protocol, NFESC was tasked by NREA to evaluate these two important claims through bench scale testing, chemical analysis, and actual field demonstrations at MCAGCC. The Marine Corps Air Ground Combat Center is located on 932 square miles in the Morongo Valley south central San Bernardino County. The Morongo Valley is located in the southern Mojave Desert and includes the cities of Twentynine Palms, Joshua Tree and Yucca Valley. MCAGCC�s mission is to train, conduct combat exercises, and assess the fighting readiness of the Marine Corps. Military activities include maneuvers with battle tanks, Highly Mobile Multi-Wheeled Vehicles (HMMWV), Light Armored Vehicles (LAV), Logistic Vehicle Systems (LVS) and other types of assault vehicles (see Photographs 2 and 3). The base also conducts air/ground combat exercises and marksmanship training on designated firing ranges. A number of training areas, including small arms ranges and practice areas for tanks and aircraft, are located in the interior of MCAGCC. These areas include Camp Wilson and the Expeditionary Airfield (see Figure 1). Logistic and tactical vehicles are heavily used in support of training operations within these areas. Most base facilities are situated in an area known as Mainside, which is located near the southern boundary, midway between the east/west limits of the base. Mainside receives a wide variety of rubber tired and tracked vehicle traffic, including civilian light vehicle trucks and passenger cars. Mainside is located five miles north of the City of Twentynine Palms and about thirty miles east of Yucca Valley and sixty miles northeast of Palm Springs, California. 1.2 SCOPE The primary objective of this evaluation was to identify the best dust suppression products for application in the following types of unpaved areas at MCAGCC:

• Roadway/shoulders • Parking lots • Areas near expeditionary airfields • Forward arming and refueling points • Open areas around buildings • Areas of high pedestrian traffic

It is anticipated that the selected dust suppressant and/or soil stabilization product(s) will be applied by assets readily available in the Marine Corps table of allowance, facility maintenance personnel or designated contractors.

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The evaluation effort was limited to areas trafficked by rubber tired vehicles, pedestrian traffic areas and other non-traffic areas. No specific effort was made in this evaluation for the suppression of dust generated from tracked vehicles, propeller down wash, or jet exhaust. If a particular product is determined suitable for heavy rubber tired vehicle loading, then it followed that it could also be suitable for propeller down wash in undisturbed open areas, and areas with light vehicle and pedestrian traffic. Products were limited to: 1) those that are used in the United States, 2) products that are non-hazardous to human health, 3) non-soluble products, and 4) products that will not contaminate ground water or harm plant and wild life as specified in manufacturers Material Safety Data Sheets (MSDS). 1.3 APPROACH The approach taken in this evaluation is listed below. (Details will be addressed in the body of this report)

1. Conduct site survey and literature search to acquire information required for dust suppression selection, and to determine a suitable location for bench scale and field-testing. Acquire specific site information including soil grain size distribution, metrological data, topography, and traffic conditions.

2. Select products for testing. Place a �Sources Sought� announcement in the

Commerce Business Daily to seek out interested companies and gather information on chemical stabilizers/dust suppressants for use on unpaved areas. Categorize and rank all product information in terms of material and labor cost and equipment requirements.

3. Develop and execute and equitable test. Conduct bench scale testing on

selected products. Field demonstrate the most promising products based on bench scale testing.

4. Conduct and economic analysis comparing chemical stabilizer and other dust

control alternatives, and evaluate their application and maintenance costs, and benefits.

5. Provide recommendations of the best dust suppressant for the needs of

MCAGCC. 2. DISCUSSION The following section details some of the important parameters considered in this study such as soil properties, climatology, temperature, wind and rain. These factors are important because they are known to affect product performance, and application process. Applicators of these products should have working knowledge of these parameters to determine the optimum product, application rate, and process. A

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discussion on methods for evaluating dust products and the criterion used to select a study site is also included in this section. 2.1 SOIL PROPERTIES Soil properties are key factors when selecting a suitable dust control product for unpaved roadways. Soil composition, grain size distribution, pH, and moisture content are general characteristics that are requested by the dust suppressant applicator to determine whether a given product will be effective, and to determine optimal application rates and methods. Section 2.1.4 through 2.2.2 provides details on soil properties found at MCAGCC. 2.1.1 Soil Description In general, soils at the Maine Corps Base can be categorized wither as old granitic alluvium or new alluvium or wind blown sand. The older alluvium is generally fine grain sands with some deposits of calcium carbonate and silicate. (Silicate tends to bond the soil particles together to form cemented deposits). The new alluvium is generally coarse grain sand with little or no calcium carbonate and silicate. It consists of debris sediments ranging from cobble-pebble gravel (formed from granitic rock, gneiss, quartzite, and marble basalt on the San Bernardino Mountains) to fine silty sand. The wind blown sand is deposited as a thin cover on the alluvium by prevailing westerly winds The soil existing at the Expeditionary Airfield (EAF) is categorized as Macagce, and lies on shoulders of erosional fan remnants formed during the Pleistocene age approximately 10,000 years ago. The soil name was given by the Natural Resources Conservation Service to distinguish this soil type from other soil types found around the Marine Corps Base. The Macagce consists of very deep, somewhat excessively drained soils forming in granitic alluvium. Macagce soils are on the shoulders of erosional fan remnants in which slopes range from 2 to 5 percent. The mean annual temperature is about 66 to 68 degrees Fahrenheit and the mean annual precipitation is about 2 to 6 inches. The soil is very pale brown, strong medium platy structure, slightly hard, very friable, nonsticky and nonplastic. The soil is excessively drained, is characterized by moderately rapid permeability, and low to medium runoff. 2.1.2 Grain Size Distribution and Plasticity Index Seven soil samples were collected from target areas near Mainside and at the EAF. Specifically, three samples were taken at the EAF, three near Range Range Road, tow on the tank trail, one at a bio-remediation site, and one at Mainside. The sites chosen were representative of high dust generation areas. Grab samples were obtained with an auger that was three inches in diameter by twelve inches long. Grab samples from a depth of twelve inches were assumed to be representative of the surface soils. A grain size analysis was conducted on the samples at NFESC to determine the distribution of soil particles, and to classify the soil in accordance to the Inifies Soil Classification System (USCS) published in ASTM D 2487-85. Refer to Appendix A for detailed analysis information.

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A shake test was conducted on each of the seven samples to distribute the soil into specific grain sizes. For soil particles finer than No. 200 sieve, the finest sieve used with the shake test, a hydrometer analysis (ASTM D 422-63) was conducted to determine the amount of PM10 in the soil sample. The specific gravity for the fines was estimated at 2.55. This was extrapolated from the Soil Conservation Service records of the area and used in the hydrometer analysis for each soil sample. This specific gravity is typical for medium to fine sand having quartz and silica. A test was conducted to acquire the plastic limit for the soil samples in accordance with ASTM D 4318-84. A wet soil sample passing the No. 40 sieve was taken in the hand, then squeezed between the fingers. The sample fell apart easy and formed cracks. A 1/8-inch (3mm) diameter soil thread could not be rolled. Therefore, the plastic limit could not be determined, and the soil was reported as nonplastic (NP). A grain size distribution curve was plotted for each of the seven soil samples retrieved. See Appendix A. Each of the soil samples showed a similar trend. Based upon the USCS, the soil at the EAF can be classified as well graded medium to fine sand with about 5-8 percent non-plastic silts. 2.1.3 pH Soil pH tests show that the sol at MCAGCC increases in alkaline content from pH 7.0 at the ground surface to pH 8.0 at a depth of 22 inches. These finding make it important to select a dust suppression product that will not be broken down by an alkaline soil. 2.1.4 Moisture Content The moisture content of soil has a direct correlation with dust emission after vehicle traffic. In desert climates very little moisture is found in the soil. Moisture to aid dust suppression is generally only present within a small time envelope after a rain event. NFESC engineers performed a series of moisture tests for validation purposes only. In each test, the soil had less than 1% moisture content. 2.2 CLIMATOLOGY The climate at MCAGCC will have a varying influence on the performance of dust suppressant products depending on the product�s chemical and physical properties. For example, products such as lignosulphonates are soluble and will leach out under rain conditions, decreasing their effectiveness as well as posing a threat to contaminate Groundwater. Due to their potential impact on product performance, rain, temperatures, wind, and humidity at MCAGCC are discussed below. 2.2.1 Rain

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Precipitation at MCAGCC, although infrequent, is important to product application and this evaluation for four reasons:

• Rain water acts as a dust suppressant, and can skew test results if one area receives more rain or rain runoff than another.

• Most products will be diluted if rain were to fall during the curing process. This may cause a loss of product strength and durability.

• Rainwater can transport product down slope of the desired site before it has cured. • Rainwater must be removed to prevent surface ponding, which accelerates road

degradation. The annual rainfall accumulation in the Morongo Valley is typically in the range of 2 to 5 inches. In the summer, meteorological conditions are predominately influenced by Pacific subtropical high-pressure systems, which generally are situated over the Pacific Ocean off the California Coast. Typically the majority of rain falls in the summer months. Field demonstration could best be conducted in the summer to monitor product performance under rain conditions. 2.2.2 Temperature Temperature is important to product storage and application because may dust suppressant products are liquid in the stored state and are affected by extreme temperature. Specific issues that temperature may influence are:

• Time of year that product is applied • Transporting and storing dust suppression products • Product curing time • Speed of product application

According to dust suppression/soil stabilizer distributors, some products (such as those based on enzymes) require minimum temperature above 63 degrees Fahrenheit to cure. Cure time is also influenced by temperature as it affects evaporation and chemical reaction. Temperatures at MCAGCC can reach as high as 118 degrees F and as low as 18 degrees F. 2.2.3 Wind The wind conditions at MCAGCC have an influence on the performance evaluation of dust suppressant and soil stabilizers. Wind speed and direction are key elements of importance since any test area evaluated will have some exposure to fugitive dust transported by wind. Field tests will require an evaluation of adjacent land used based on their potential to contaminate sites with fugitive dust. Wind speed is also important from eh standpoint that it affects soil lift and dust generation. These variances occur when wind blows migrate dust into or out of the proposed test bed area, and should be considered when evaluating different test products.

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The predominant wind direction across the base is from the northwest to the southeast, following the canyons between the three mountain ranges that transect the base from the northwest to the southeast. Afternoon winds are typically stronger than the morning winds. Wind speeds were found to reach a magnitude of 17 to 21 knots (24 miles per hour or 39 kilometers per hour) at Twentynine Palms about 1.0 percent of the time, (152 hours of 14,636 total hours). Calm winds (less than 1 knot) were predominant 14.7 percent of the time (2154 hours of 14,636 total hours). This data was for the period 1989 to 1990 as shown in Figure 2. It was determined that the optimum time to run testing would be in the morning and optimum test orientation would be perpendicular to the northwesterly winds. 2.2.4 Humidity Humidity is a final factor that affects dust suppression product performance. Products containing Magnesium Chlorides are hydroscopic, meaning they draw moisture from the air. This is a desirable characteristic since moisture increases the mass of individual soil particles and adds to the surface tension, keeping dust levels down. In general, for hygroscopic products to be considered effective, humidity must exceed 30%. The Joshua Tree National Monument weather station, located just south of MCAGCC, records reading from the Oasis Visitor center at Twentynine Palms. The yearly average humidity is 21.6%, while the month of June has an average humidity of 12.3%. Since the humidity is well below 30% throughout the year, and even lower in summer months, products that rely on humidity are not considered practical. 2.3 SELECTION OF DUST SUPPRESSANT The selection of dust suppression products to evaluate was approached in the same manner as would be required to award a contract. The selection process was initiated by means of open advertisement. The following details the considerations and methodology behind acquiring test candidates for this study. 2.3.1 Dust Suppression Selection Considerations The Government is required to have open competition for large contracts (such as this study), initiated by open announcements such as those provided in the Commerce Business Daily. The main purpose of this policy is to provide any interested party an equal opportunity to compete in the bidding process. In terms of awarding a large contract for dust suppression and soil stabilizers, which is the follow-on goal of this study, several issues arise. First, there are literally hundreds of products functioning on different principles of dust suppression, so there is not one clear choice. Second, it is erroneous to procure any one product based solely on up front cost. Third, no standards presently exist for pre-qualifying products of this nature. Finally, past product comparison demonstrations used to select suitable products have had inherent flaws that have been the subject of contract disputes. Variability of soil and traffic conditions, as well as exposure to fugitive dust and cross contamination on field test strips, are some of

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the issues that have resulted in costly disputes. These issues are addressed further in section 2.5.4 and section 3. 2.3.2 Questionnaire In order to acquire product information and evaluate company interest, a �Sources Sought� announcement was placed in the Commerce Business Daily (See Appendix B). Product information was requested in the form of a questionnaire that each respective company was required to fill out and return to NFESC (See Appendix B). As a result of the announcement, ten companies responded with filled out questionnaires and indicated interest in comparison testing of their product. A list of responders along with phone numbers, point of contacts, and product descriptions was extracted form the questionnaires and is included in Appendix C. 2.3.3 Tradeoff Analysis A tradeoff analysis was performed to evaluate the products. The products were categorized into one of the five following classifications: surface binders, hygroscopic, soil stabilizers, particle adherence, and membrane/cover as shown in Table 1. Each of the products were then ranked on estimated material cost, labor cost, and expected service life from information acquired form the questionnaires. The following criteria were assigned weighting factors:

• Curing time • Projected service life • Projected Cost/Material and labor • Equipment requirements

The products that ranked the highest in each classification were selected for further evaluation. They are marked with an asterisk in Table 1. See Appendix C for comparative analysis. NREA reviewed and concurred with the five selected products. 2.4 SITE SELECTION As mentioned in the approach, two separate phases of testing were to be conducted: bench scale and field demonstration. This evaluation required secure sites: (1) to implement six text beds and (2) an unpaved roadway for follow-on field demonstration. The site selection criteria for each phase are discussed below. 2.4.1 Criteria Parameters such as soil characteristics, security, wind direction, and access to electric power were some of the aspects evaluated to aid in the site selection process for the bench scale testing. The same parameters, except the need for electrical power, were also used for field demonstration site selection. The parameters are discussed below.

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1. Soil Characteristics: Selection should be based on a site whose soil properties are representative of the soils where dust generation is a concern. Grain size distribution, with particular emphasis on the percentage of fines, is important in selecting a site; since the effectiveness of many dust suppressants is directly related to soil fine contents. Another important consideration includes selecting soils/lands that are not contaminated or are not environmentally protected.

2. Security: Security is needed for both sites during the construction and testing

phased of the study. The area under consideration would need to be isolated from pedestrian and military traffic during application and curing of the test products.

3. Wind Direction: For bench and full scale testing it is optimal to orient the test

sections perpendicular to the prevailing wind direction to minimize cross contamination form adjacent treated soils or other adjacent areas of high dust generation. Failure to do so could result in mixed contamination form non test-related dust generation.

4. Electric Power: Access to an adequate power supply is important during bench

scale testing. A system capable of delivering 240 volts to run electrical equipment was required. The test site should be located within 200 feet of an electric power source.

2.4.2 Available Areas A site survey was conducted at the MCAGCC using the parameters discussed above to determine a suitable location for the test beds. Personnel from Natural Resources and Environmental Affairs Directorate, Range Operations and the Air Ground Support Element provided NFESC with a tour of possible test site areas around MCAGCC that are known to generate dust from rubber tires vehicles. Some of the areas observed included:

(1) Range Range Road; (2) Various parking lots on Mainside; (3) Unpaved roads near the base landfill and near the Navy Hospital; (4) Road shoulder along Del Valle Road; (5) Recreational activity parking lots located at Del Valle Field; (6) Area near the Jet fuel Bio-remediation pile; (7) Camp Wilson; (8) Various locations at the Expeditionary Airfield

NREA personnel suggested that the EAF be investigated as a potential site because of its severity of dust generation and impact on personnel. As a result, the EAF was chosen for test bed implementation. (See Appendix D for environmental impact review). See Photograph 4 for view of selected site. For a field demonstration, Range Range Road was selected based on a group decision with Facility Maintenance, NREA and NFESC.

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2.4.3 Description of Selected Site A map showing the location of the selected site for bench testing is represented by Figure 3. The site is located approximately 250 feet from the edge of the runway apron on the northwest side (between runway markers 6 and 7), and falls outside the 200-foot setback requirement established by EAF personnel. The approximate coordinates of the site are 34o 17�56� N longitude and 116o10� 2� W latitude. The soul found in this area is typical of old alluvium found throughout the base. It is well-graded sand with 5-8 percent silts. The area has an adequate electrical power source (3 phase, 209 volts and 120 volts). A topographic map of the site is shown on Figure 4. The site chosen for field demonstration is discussed in section 5 of this report. 2.5 SELECTION OF A METHOD FOR EVALUATING DUST GENERATION Commercial and military activities have employed numerous products in an attempt to control dust generated from vehicles traveling over unpaved roadways. Frequently, dust suppressant products are selected based on one or more of the following criteria: manufacturers� literature review, product�s past performance, bench scale testing, and field evaluation. Numerous tests and evaluations have been performed to quantify dust generated from vehicles traveling over test strips of land. The goal was to find the best product for a given set of soil and climate conditions. These studies used or considered one or more of the following methods: sedimentation, filtration, or photometric. The following is a brief description of the limitations and advantages of the three methods. 2.5.1 Sedimentation Sedimentation, which depends on gravitational forces to settle out lifted dust, is a mass measurement technique using open top collectors such as cans or glass jars to trap dust particles. These containers are positioned at various distances from a treated roadway. After an exposure for a set period of time (30 days), the particulate in each container is weighed and compared to other treated test areas. Variables that skew direct comparison exist in open field studies (and uncontrolled traffic), where different products are laid in parallel or adjacent to one another. In general, these variables have been the cause of dispute. The concern is not so much with the capture collection method, but with the uncontrolled source of dust captured. Influencing factors are cross contamination from adjacent test plots, product carry over from adjacent areas, variation in soil, and unequal exposure to rain water run-off. Other variables such as fugitive dues, traffic flow, braking, variable vehicle speed, weight and shape of vehicles can skew direct comparison. One advantage of sedimentation, however, is its minimal cost. 2.5.2 Filtration One method of measuring dust generation is based on filtration technologies. Filtration basically consists of collecting dust by using a vacuum pump and filter medium. Although filtration techniques have been used in past dust suppression studies, no tests have been done under fully controlled traffic conditions. Filter systems have been placed

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on stationary platforms adjacent to treated areas and on moving vehicles. The main concern with past tests performed using filtration technology is the variability of traffic and wind conditions on sections of treated roadway. Dust capture will vary because ambient wind conditions are not uniform, causing variability at the dust collection capture point. Costs are high; since several vacuum pump systems must be placed at various locations around the test strips so that wind changes can be modeled into dust capture mass determination. To avoid modeling, some activities have mounted a vacuum system close to the tire of a test vehicle. This method had provided some quantitative results. An advantage of filtration is that results can be obtained fairly quickly. 2.5.3 Photometric Method The photometric method is based on measuring light transmission through the dust cloud created by a passing vehicle on an unpaved road. Opacity measurements are taken right after passage of a control vehicle across a select point. Generally speaking, the method is subject to the same inaccuracy as the previous two and is subject to additional uncertainties caused by the equipment�s response to wind speed, wind direction, sunlight intensity and cloud cover. 2.5.4 Selected Method NFESC reviewed the above three methods for quantifying dust generation from wheel traffic on test soil. It was determined that a filtration technique coupled with a controlled test bed (free of suppressant) consisting of a spinning wheel would be optimum for this study. The dust released from spinning wheel would be vacuumed through a duct as a dust laden air stream where a dust sample can be filtered out iso-kinetically using standard EPA Test Method 5. The control test bed would eliminate the variables associated with open field studies, and provide accuracy and repeatability. The test bed is described in detail below. 3. TEST BED This study required the construction of six identical test beds so that each product tested would be exposed to the same conditions. The test beds are configured to simulate the abrasive force of a wheel rolling on treated soil. Soil is placed in a concrete containment structure, leveled and compacted. The soil is treated with a chemical dust suppressant. A test wheel equipped with a dust collection system revolves around the treated soil to wear the surface. Dust is collected and weighed for comparison. The primary components of the test beds are: (1) the secondary containment system, (2) wheel apparatus, and (3) a dust collection system. See Photograph 5. The following subsections discuss each of these components, as well as some of the secondary components. 3.1 SECONDARY CONTAINMENT

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The secondary containment system shown in Figure 4 was fabricated with 4000 psi concrete and was designed to hold up to 11� of soil. Its purpose is to eliminate the risk of contaminating nearby soil or groundwater if the product applied is determined to have exceeded contaminant levels. It also serves as a containment for recollecting leachate for follow-on leach tests and provides an unyielding subgrade to eliminate subgrade failure as a potential cause of product failure. The portable containment system has four lift points found on the sidewalls to facilitate lifting for relocating. It has four bolts located in the center for anchoring the wheel apparatus as discussed below. As shown in Figure 4, two 2� diameter conduits were installed in the pad during fabrication and protrude through the surface near the center. These conduits serve as a means to run hydraulic hose lines to the hydraulic motor and wheel apparatus discussed below. A drainage port is located on the berm to collect leachate and to drain water. 3.2 DUST COLLECTION SYSTEM The purpose of the dust collection system is to provide a method to measure the dust generated from a moving wheel. A drawing of the system is shown in Figure 5. Photograph 6 is a side view of the assembled system. As seen, the system consists of a large industrial blower, lightweight ducting, rotator assembly and a shroud that surrounds a 30� tire. The dust collection system is designed for a flow rate of 700 cubic feet per minute to maintain the 3,565 feet per minute air velocity though the air duct needed to prevent the dust particulates from settling out of the air stream. The shroud is adjustable allowing a 2� to 4� gap between the soil surface and the bottom edge of the shroud. The air velocity through the shroud around the wheel is designed to entrain particles less than 100 microns. Iso-kinetic air sampling for total suspended particulates above 0.6 microns is performed 9 duct-diameters down stream from the blower. The conduit is supported by uni-strut channel anchored to the outside wall of the secondary containment. 3.3 ISO-KINETIC SAMPLER The iso-kinetic sampler used in this study is an air-sampling device that extracts a sample of moving air through a stainless steel probe inserted in the exhaust stream of the system to be analyzed. The sampler draws the exhaust gases through a filter, capturing any particulates in the sample greater than the filter porosity. The exhaust gases then travel into the control unit, where other important air quality measurements can be made. All of this is done iso-kinetically, or at the same velocity the exhaust gas is at in the original air stream. The purpose of using the iso-kinetic sampler in this study is to provide a standard method for mass determination of particulates exiting through the exhaust conduit of the dust collection system. The system used is the Nuteck Iso-kinetic Stack Sampler. It is designed to meet all Environmental Protection Agency (EPA) Standards for iso-kinetic source sampling as outlined in the Office of Air Programs Publication N. APTD-0576. (The EPA method is the most generally accepted of all particulate sampling methods for legal and scientific documentation). The sampler consists of a control console, a sample case containing a heated filter and cyclone, impinger, glassware, and umbilical cord, a nomograph, and a sampling pilot tube assembly consisting of a nozzle, probe, and pilot

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tube. See Photograph 7 through 9. The filter paper used in the sampler is a quartz paper filter, 0.6 micron rated at 99.97%. 3.4 WHEEL APPARATUS The purpose of the wheel apparatus is to provide a means to simulate wheel traffic on treated soil. Two test wheels were fabricated. (One is to serve as a backup in the case the other malfunctions). The system is driven by a hydraulic motor and hydraulic power unit that turns a center sprocket by using a chain. The speed of the wheel is variable, ranging from 0 to 10 mph. A weight attachment is positioned near the wheel to allow for the addition of 50-pound plates to vary the wheel loading, simulating variable vehicle traffic. The lugged wheel is a 30� tall wheel taken from a military utility trailer. The wheel axle is constructed with A36 steel and hinged at the center to allow for vertical motion of the wheel for slight variations in soil surface and rutting. Quick disconnects on the hydraulic motor are provided for easy removal of the hydraulic hose lines. The wheel apparatus can be disassembled into 75-pound sections for transport by two individuals. See Figure 6 for cross section schematic. 3.5 WHEEL COUNTER The wheel counter, used to keep track of wheel passes over the test soil, is a �Countmate� vehicle traffic counter that is triggered by air pulses generated from the impact of a tire passing over a rubber tube. The wheel counter, which is the size of a large writing pen, is battery operated and has a liquid crystal digital display. The rubber counter is anchored to the secondary containment wall. 3.6 SUPPORT STRUCTURE Channel steel was used to fabricate a support structure to hold the dust collection system in place. The structure consists of two vertical and two horizontal members. The vertical channel steel was anchored to the secondary containment wall and supported on top with 1/16� guy wire. 3.7 HYDRAULIC UNIT The hydraulic unit consists of a diesel driven engine, hydraulic pump, filter, hydraulic hoses, disconnects and appurtenances manufactured by Stanley Hydraulics Tools. It is capable of delivering 2000-psi pressure at a flow rate of 8 gallons per minute. The purpose of the hydraulic unit is to power the hydraulic motor located on the wheel apparatus. The system is equipped with a priority valve that adjusts the flow rate. A priority valve setting of four gallons per minute can operate the wheel at 24 revolutions per minute. See Photograph 10 for side view and Figure 6 for hydraulic schematic. 3.8 PROTECTIVE COVER

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A protective cover was placed over each test bed to minimize cross contamination from adjacent test beds and windblown sand. The cover material, known as �Sunbrella,� is a breathable material that allows ultraviolet light to penetrate. It was anchored to the secondary containment with a 2�x4� lumber frame around the test bed perimeter. It was designed to withstand the high wind gusts that are typical of the Twentynine Palms area. See Photograph 11. 3.9 TEST BED SETUP PROCEDURE

1. Check tire pressure prior to each test. Insure the same tire pressure is maintained throughout each test.

2. Clean out each duct, blower, and wheel shroud before each test run. This can be

accomplished by using a portable blower (capable of delivering 90 mph winds) to purge conduit of dust collected on the inside surface. Purge for 1 to 2 minutes in each direction of the ducts. Purging will insure that only dust generated from that test bed will be collected.

3. Install test wheel apparatus on secondary containment pad. This is a two-step

process. First install center gear apparatus, then install test wheel and axle. Align the center gear apparatus plate holes to mate with the 4-1/2� bolts that protrude from the center of the concrete pad. Secure with appropriate nuts and washer. Install test wheel (with shroud attachment) and axles on center gear apparatus. Place 25 lb weights on axle attachment. Maintain constant weights throughout test run.

4. Place the hydraulic power unit near the test pad. Each of the two hoses should be

placed through the two conduits that run through the secondary containment structure. See Figure 6. Connect hose to the hydraulic motor located on the center gear apparatus. Check each of the hose connections for a proper seal.

5. Install dust collection system as shown in Figure 5. Insure the same orientation is

maintained on each test-bed. Insure inlet and outlet ducts fit squarely on blower. After installation, place a 4�x4��3/4� thick plywood sheet under test wheel and operate blower for 10 minutes to remove any remaining dust. Maintain the same wheel configuration when conducting this pre-test setup (Photograph 6). While the blower is operating, adjust throttling valve on blower outlet until the desired static and velocity pressure of 0.8mm is achieved. This is accomplished by inserting the pilot orifice probe inside a pinhole located on the suction side of the blower. See Photograph 12. After achieving the required velocity and static pressures, lock the lever for the throttling plate in place.

6. Install iso-kinetic sampler consisting of the main control unit and pump, umbilical

chords, impinger system, filter box, filter glassware, and stainless steel probe and nozzle as spelled out in Nutech instruction manual. Weigh filters and glass capture components. Conduct leak check testing, as outlined in EPA standard

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Method 5. A leak test is required to insure Iso-kinetic sampling occurs on each run. Essentially, the leak test involves insuring that all connections in the sampling train are free from excessive leakage at a vacuum pressure of 15 inches Hg. Insuring that the vacuum is consistent before and after testing is key to obtaining consistent and accurate results. Use a trained and experienced technician to perform this phase of testing. Other key points to installation are maintaining of consistent orientation of the sampling port within the exhaust port. Insure that ice is maintained in the impinger box throughout testing as required to maintain dry air throughout the iso-kinetic sampler. During actual operation, move nozzle horizontally through the duct such that the nozzle is parallel to the flow of air.

7. Install traffic counter on test pad. Position the rubber hose so that the wheel

passes it at a right angle. Zero the traffic counter at the beginning and take reading after completion of the test run. Confirm by using a time clock and count revolutions per time.

8. Setup portable weather station and log wind speed, direction, temperature,

humidity, and barometric pressure as outlined on data sheets.

9. Operate test wheel at established speed and time. Use all safety precautions established in Appendix E. Verify if wind conditions are optimal for testing. (Wind velocity of 10 mph or more is judged to be the cutoff for testing.) Verify that wind direction is acceptable with the dust collection exhaust orientation. Exhaust must be directed away from the moving wheel to prevent re-introduction of dust into ventilation system. If not, suspend testing.

10. Conduct leak test on iso-kinetic train at the completion of the wheel run. Remove

front end of filter train and filters for weighing of dust captured.

11. Measure surface deflection and baseline deflection using berm wall as fixed set points. Take initial baseline measurements of the soil surface prior to testing. Use T-section aluminum metal gage (12 ft long) on established reference points on the berm wall. Measure four locations along the path of the circular wheel track using depth measurement gauge. Record reading in centimeters. After each test, re-measure to determine the amount of surface wear (deflection) created by the test wheel.

12. Upon completion of the surface deflection measurements, remove the cover from

the next test bed. Remove equipment from the previous test bed and set it up on the next test bed. Cover the previous test bed again to prevent cross contamination.

13. Collect grab soil samples from each test pad after product application and curing.

Obtain at the surface to depth of about 3 inches. Complete Chain-of-Custody

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forms, keep soil samples in cooler at 65 degrees Fahrenheit, and send to laboratory. Analyze for the following:

Total metals, to determine if the California Total Threshold Limit Concentration (TTLC) values are exceeded. Waste extraction test (WET) for metals to determine if the Soluble Threshold Limit Concentration (STLC) values are exceeded. Total Organic Carbon (TOC) to determine if the organics exceed permissible limits. 4. TEST AND EVALUATION Test and evaluation was conducted from January 1997 to July 1997 at the Expeditionary Airfield near the northwest side of the runway (Figure 3). This consisted of evaluating the application process of each product, measuring the dust generated from simulated the application process of each product, and determining surface abrasion resistance in terms of soil water. Other aspects of interest were soil strength after curing (unconfined compression strength), product penetration, and soil performance after exposure to water. Special emphasis was placed on each test bed to insure equal testing conditions. Properties such as soil surface, slope, compaction and exposure were maintained on each test bed so that direct performance comparisons could be accomplished. 4.1 TEST BED PREPARATION Dry silty sand, typical of the soils found at the EAF, was taken from the test site and placed inside each of the secondary containment pads with a front-end loader. The soil surface was then raked and leveled so that the surface was even with the top of secondary containment wall. Rocks larger than 2� in diameter were hand removed while raking to level out the soil. After leveling, the soil was hand compacted using a ten-pound hand compactor (10�x10�). After 4 passes with the hand compactor, the soil surface was approximately 1� below the top of the secondary containment berm. A standard hand held cone penetrometer was used to measure unconfined compressive strength to insure equal compaction on each test bed. The test beds filled with hand compacted soil were exposed to the environment and allowed to settle over a two week period to follow-on product application. 4.2 PRODUCT APPLICATION Product application began January 1997. Product was applied on each of the designated test beds within a two-week window except as noted in Table 1. NFESC engineers monitored and recorded ambient weather conditions and evaluated product application process during soil treatment by each respective company. Data collected includes: equipment used, volume of product applied, time to apply, and support equipment requirements. Table 2 summarizes the evaluation data sheets found in Appendix E. The company names are tabulated in the order in which they applied their product. Photographs 13-23 illustrate product application.

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After product application, the treated soil in each test bed was allowed to cure for 7 days while exposed to ambient conditions without any type of loading. The beds were then covered to prevent any significant contamination from neighboring areas and the adjoining test beds. After 28 days the covers were removed the day before performance testing. 4.3 PRODUCT PERFORMANCE TESTING Performance of each product was evaluated by using the test wheel apparatus to simulate wheel traffic disturbance of the treated soil. Testing began in February 1997. The primary goal of the test was to obtain data from each test bed so that a direct comparison of dust mass collected could be made. The test wheel, dust collection system, integrated and iso-kinetic sampling train were assembled as depicted in Photographs 4 and 12. A test run was conducted on the baseline test bed to establish a boundary for testing. Key parameters determined were optimum run time, wheel speed, and filter capture. Every 30 minutes the filter box was opened to determine the extent of dust buildup inside the filter. At two hours, it was determined that the filter had substantial dust for a good baseline. Based on the initial run, a minimum run time of 2 hours and a speed of 18 to 24 revolutions per minute was set for follow-on testing (2,160 passes.) Testing which consisted of dust capture and wear testing was conducted on each of the test beds over a two-week period. See Photographs 24 and 25. Data collected form the test is summarized in Table 3. Testing was performed in the same order in which products were applied. Mass determination of the collected dust samples were measured in a clean room located at NFESC. Each of the samples showed distinctive color variations when compared to the baseline sample. All of the test beds treated with products generated less dust than the baseline. The test beds that generated the least amount of dust were those that were treated with Envirotac II and Soil Sement as shown in Table 3. The test bed with dewatered residual wood fiber generated less dust than the baseline but was easily dislodged with foot traffic. Asphotac provided only minimal dust suppression capability when compared to the baseline. It was determined that it was not performing as claimed due to the relatively high pH of the existing soil. Dustrol was not tested since the product did not harden (cure) as required. According to the manufacturer the product reconstituted itself during transport or storage. As a result of the first series of tests, it was determined that only Soil Sement and Envirotac II of the 5 products would be further tested. Table 4 outlines the results of the Spring and Summer tests. The Spring test included the testing of Ubix enzyme since the Aviation Ground Support Element (AGSE) of MCAGCC was highly interested in its capability. The last series of test were conducted 3 weeks after simulated rainwater application on test beds as shown in Photographs 26, and 27. During simulated rain test the soil treated with Envirotac II formed some discernible ruts. See Photograph 28. 4.4 UNCONFINED COMPRESSION TEST Sample specimens from each dust suppression product were made immediately after application on the test beds. This consisted of mixing 170 cubic inches of loose silty

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sand soil with 160 ml of product for 5 minutes in a plastic bucket. The soil was then placed in 2 cardboard cylinder canisters (3� diameter by 6� high). Consistency in soil placement was maintained to remove soil voids. The soil was compacted with a wood dowel every third of the distance up to the top. At the top the product soil mix was leveled to provide a smooth surface for follow-on unconfined compression test. The samples were placed on top of their respective test bed and allowed to cure under ambient conditions. After 60 days of exposure to ambient conditions at MCAGCC, the samples were transported to NFESC for unconfined compression test. The cardboard canisters that were used to form the soil samples were removed. During the removal process some of the samples had broken apart. A leather sleeve was placed over the ends of the sample to insure a flush interface with the press. Once in the press the samples were subject to a uniformly applied increasing load until rupture. See Photographs 29 and 30. The results of the data are provided in Table 5. 5. FIELD DEMONSTRATION A field demonstration was conducted along an unpaved section of roadway to substantiate the results of the bench testing. The field demonstration consisted of applying Envirotac II and Soil Sement, the products that generated the least amount of dust, to a test section of unpaved roadway on base. The evaluation process was conducted visually by monitoring dust as random vehicles passed through two treated sections. Below describes the selected site, the application process, and provides an evaluation at 4 hours and at 28 days after product application. 5.1 SELECTED SITE The site selected for field demonstration is an unpaved roadway known as �Range Range Road� located at the intersection of Del Valle Road and tank trail. This unpaved section of road is trafficked primarily by rubber-tired vehicles. For evaluation purposes this area was divided into two 300-foot sections for the application of two products. The sections are separated by a 50-foot section of untreated roadway. See Figure 7 and Photograph 31. The unpaved roadway is approximately 20 ft wide, with a varying cross section throughout its length. It can be characterized as having a cross section of an inverted crown. Rocks and boulders greater than 4� are found throughout the section. The soil at the time of product application had less than 1% moisture content and is classified as a non-plastic silty sand with less than 5% silts typical for many areas throughout MCAGCC. The edges of the roadway on both sides are built up with loose uncompacted wind blown sand. In close proximity and merging into the roadway down road of the test area is a tank trail with non-compacted fine sands. Considerable dust is generated from this tank trail area. 5.2 SITE PREPARATION Site preparation was conducted in May 1997 and involved leveling and crowning an 800-foot section of road to provide and even and well drained base for product topical

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application. A Marine Corps grader/scarifier was used for this purpose as shown in Photograph 32. As a result of the grading, a slight amount of loose soil was carried over form the roadway edges onto the road surface. Also larger boulders were lifted out by the blading process. At the completion of grading, rocks larger than 4� in diameter were removed form the test area, and the road was opened up for traffic. Less than 200 vehicles passed through the prepared surface between the end of site preparation and the time of product application the following day. 5.3 PRODUCT APPLICATION Representatives from Environmental Products (Envirotac II) and Midwest Industrial Supply (Soil Sement) managed the application process. Below describes the steps taken by each in chronological order. Midwest Industrial Supply applied their product on 22 May 1997 starting at approximately 0930 in the morning. The test section was roped off to divert vehicle traffic other than the required application equipment. Midwest used their own computer controlled sprayer/water truck to first apply water on the 300ft section of road closest to Del Valle Road. They then applied their product, Soil Sement in three passes. See Photograph 33 & 34. A 9:1 product to water ratio was applied on the first two passes, while the third was a 4:1 ratio. After each pass the product was allowed to penetrate into the soil until saturation occurred. A steel roller (provided by Facility Maintenance) was driven over the treated soil after the first pass. After the third pass the treated test section was allowed to cure without any vehicular traffic for 4 hours. At that time the roadway was reopened. Environmental Products applied their product on 23 May 1997 starting at 0900. Again, the test section was blocked off to vehicle traffic other than required equipment. An 800-gallon towable tank belonging to the company was used to apply product on their designated 300-foot section of road furthest from Del Valle Road. Initially the product was applied to 50 feet of roadway and rolled with a steel roller a few minutes after product application. However, the application technique was quickly changed since the steel roller picked up sheets of soil and product in areas of low product penetration leaving behind a patchy finish. The applicator roller compacted the remaining 250 ft section without product. After completion of dry rolling they applied product in two coats at 4:1 concentration. The product was allowed to penetrate into the soil between applications. After the second pass the treated section was allowed to cure without any vehicular traffic for 4 hours. At that time the roadway was reopened. 5.4 EVALUATION Engineers from NFESC evaluated the two 300 ft. test sections. Evaluation was based on visual inspection of dust generation behind moving vehicles, and signs of rutting, surface finish, skinning, and separation. The products were visually inspected at 4 hours and 28 days after application. Product performance was ranked from one to ten, ten being best. See Table 6.

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5.4.1 Four Hours after Application Envirotac II and Soil Sement both suppressed dust when compared to the untreated roadway nearby four hours after application. For this reason they were given the same ranking for dust suppression. Rough surface finish occurred in each test section. Envirotac II had ruts and flaking that formed in the first 50 feet, where the steel roller had been used after product application. Minimal rutting occurred on remaining section, where the soil was rolled before product application. The Soil Sement section had several areas where penetration was less than ¼ inch. On the north edge of the Soil Sement section appeared a 1/4-3/8� skin over the surface that was lifted by vehicles with lugged tire patterns as those found on a construction grader. See Photographs 35 and 36. Underneath the skin, the soil appeared wet but not bound together. 5.4.2 Twenty Eight Days After Application Envirotac II and Soil Sement were both suppressing dust twenty-eight days after application when compared to the untreated roadway nearby. However, numerous potholes had developed within the Soil Sement test section. The section had approximately twice as many ruts as the Envirotac II section. Each of the two sections showed areas where product appeared to have penetrated less than 3/8 inches. This was noted due to uplifting of the 1/4� surface skin. Discernible amounts of dust were lifted from vehicles that passed these rutted areas. 6. ECONOMIC ANALYSIS An economic analysis was performed on several dust control alternatives: covering an unpaved roadway wit asphalt, applying a chemical dust suppressant product, soil cement stabilization and water application. Note that the alternatives are not necessarily recommended since paving roadways removes the austerity of training operations necessary to MCAGCC�s training mission, cement stabilization is not generally used as a wear surface and water is a limited resource for this area. The analysis was done to determine feasibility of applying a chemical dust suppressant/stabilizer and a basis for comparison. To conduct this analysis several assumptions were made to simplify the four alternatives. Cost estimates for each alternative were broken down into soil preparation, initial application, material cost and annual maintenance costs as discussed below. For comparison, a project life cycle of eight years and a roadway 24 feet wide by 1 mile long was used to calculate total and square foot cost. Due to the variation of pricing for different geographic and population areas, estimates were generated for MCAGCC Twentynine Palms only. 6.1 ASPHALT

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In general, unpaved roadways are improved with asphalt when average daily traffic exceeds 300 vehicles per day. Asphalt roadways provide an effective dust control alternative to unpaved roadways. Placement of asphalt at MCAGCC is usually performed by contractors. A considerable amount of effort goes into this process, such as leveling, subgrade compaction, applying aggregate base and the actual placement of asphalt. Traffic loading dictates the thickness of the base and the asphalt. For comparison purposes, a 2� thick asphalt layer over four inches of class II base is assumed for this analysis. Asphalt can last for several years with very little maintenance if adequate drainage is provided and the subgrade is well compacted. For this comparison a service life of 8 years with no maintenance is assumed. Asphalt provides good driver visibility, road traction, and dust control. Compared to dust suppression products, asphalt is almost double the cost over an 8-year timeframe. 6.2 CHEMICAL STABILIZERS AND DUST SUPPRESSANTS Chemical dust suppressant methods are considered practical for use on low to medium trafficked roadways. With proper application it is estimated that chemical dust suppressants can provide suitable dust control for a period ranging from 1 to 3 years, depending on traffic volume. The process of application can be either topical or blended in, whereby the topical is the most advantageous from an application and cost standpoint. Application rate for the polymer products tested can vary from 25 square foot to 50 square foot of soil surface per gallon of concentrate. The average cost per square foot value used in this comparison was calculated based on the cost of the two most promising polymer products tested (1 gallon for 45 square feet). The products were assumed to be applied directly over the surface with minimal soil leveling and compaction. Labor costs are not included for site preparation, under the assumption that the Marines have the equipment and manpower to perform leveling and steel roller soil compacting operations. Application of product can also be completed by the Marines but may require a dedicated vehicle. (Note; It would be advantageous to have some experience in application since deviation in soil characteristics may require a modification in application rate and process.) Initial applications included several coats of product, which totaled to approximately $0.08 per square foot. Annual maintenance costs consist of additional applications of the product, typically a single coat. Therefore, maintenance costs are substantially lower than the initial application costs. Some benefits associated with chemical stabilizers are good dust control, increased driver visibility over untreated soil, effect of natural terrain important in troop maneuvers, and minimal soil preparation. 6.3 PORTLAND CEMENT STABILIZATION Portland cement soil stabilization methods have been used extensively to strengthen soils typically under asphalt or concrete roadways and runways. To a lesser extent they are used as a dust control although not generally recommended as a surface for traffic. The process of stabilization is extremely labor intensive requiring the mechanical mixing of

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cement into the soil, leveling, compaction, and watering. Seven percent by volume is a typical ratio of cement to soil used to stabilize under expeditionary runway matting. For this analysis, cost for cement stabilization was estimated using a 7% cement to soil mixture within the top 6 inches of soil. Portland cement can be blended in by equipment, (such as a grader) but will perform better if it is mechanically mixed into the soil (i.e. rototilled). Labor costs are not included in this comparison. It is assumed that Marines will be used to perform the stabilization. If labor and equipment costs were included, the cost shown below could easily double. Failure of a cement-stabilized soil is a function of loading and quality control during initial construction. Useful service life under traffic conditions is variable, but for this analysis is assumed to be 4 years. Cement stabilization is not recommended as a traffic surface. For comparison, the estimate above reflects only material cost, which is based on current cement price of $150 per pallet (35-94 lbs. Bags). Introducing a higher cement to soil ratio would increase service life, but at a significant increase in cost. Capital requirement is quite high and may require network after 4 years when subjected to wheel loading. Compared to dust suppression application the cost of material used in cement stabilization alone is double the cost. 6.4 WATER APPLICATION Dust control by applying water on the soil surface is frequently used for short-term requirements. This method is generally effective up to a few hours, though its effectiveness varies based on traffic and climate conditions. The application of water is simple, requiring only a water truck with a spray boom. Volume of water required for dust control is variable based on existing conditions. For this comparison, an application rate of 5 gallons of water for every 40 square is assumed. Fresh water extracted from a well was used to determine cost. Costs for initial and subsequent applications were estimated assuming no earthwork was needed, and that the soil was watered every two working days. Labor costs are not included, under the assumption that the Marines would apply the product. Water application was the least expensive in terms of initial application cost when compared to the other alternatives evaluated. It requires no soil preparation, is a fair dust suppressant, and needs no curing time. Unfortunately, it must be reapplied frequently to be considered effective. Annual maintenance costs easily exceed that of the other alternatives. Costs were estimated assuming that the military labor was employed, and that existing equipment was used. This option is not recommended at this time due to the high maintenance costs and public awareness of water conservation. 6.5 COMPARATIVE ANALYSIS The results of the economic comparison are depicted in Tables 7-10. The results give an estimate of the four measures of dust suppression, but are only as accurate as their assumptions. In reality, soil conditions can very widely, even within a localized area. Soil preparation costs play a large role in the overall cost of each alternative and can

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escalate quickly when fortifying poorly compacted subgrades. Additionally, labor costs estimates, which included equipment costs and delivery costs of the product, can vary substantially. 7. TOXICITY FINDINGS One objective in this study was to determine whether the dust suppressant products evaluated pose a risk to human health and the environment. Based on evaluation of the Material Safety Data Sheets (MSDS) provided by the manufactures (See Appendix C) and discussions with representatives from the local water boards, it was determined that none of the products would pose any significant threat to human health and the environment if applied with the recommended dosage and application techniques. This section documents three basic chemical analyses conducted on each of the tested products and the untreated soul to expose any hazardous material or pollutants not reported by vendors. The analysis includes the following tests: Total Threshold Limit Concentration (TTLC); Soluble Threshold Limit Concentration Toxicity Leaching Concentration (STLC); and the Total Organic Carbon (TOC). See Appendix F. 7.1 TOTAL THRESHOLD LIMIT CONCENTRATION (TTLC). The results of the analysis for TTLC are shown in Table 11. Findings indicate that some traces of metals exist in the untreated soil sample. These metal traces are arsenic, barium, lead, vanadium, and zinc. These metals and their concentrations are nearly identical to concentrations reported in the treated soil samples consisting of Soil Sement, Asphotac, UBIX 10, Envirotac II. However, none of these metal concentrations exceed the California TTLC limits. A slight trace of chromium appeared in the UBIX 10 material, but the chromium concentration is much lower than the acceptable limit of 2500 ppm. Based upon these TTLC test results, there are no traces of metal elements that exceed the CAM-TTLC permissible concentrations. Therefore, the treated soil does not pose a human health threat nor a threat to the environment. 7.2 SOLUBLE THRESHOLD LIMIT CONCENTRATION (STLC) Similarly, the results of the analysis for Soluble Threshold Limit Concentration (STLC) are shown in Table 12. The analytical results indicate that some traces of metals exist in the untreated sample. These metal traces are barium, lead and zinc. These metals and their concentrations are nearly identical to concentrations reported in the treated soil samples consisting of Soil Sement, Asphotac, UBIC 10, Envirotac II. Each of the samples showed a STLC concentration much less than the acceptable limits. Based upon the STLC results, the treated soil does not pose a human health threat or a threat to the environment. 7.3 TOTAL ORGANIC CARBONS The results of Table 13 show that the Asphotac has a Total Organic Carbons (TOCs) level of 650 ppm. This concentration level is lower than concentration levels of crude oil

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or other oils heavier than diesel fuel. However, the product is most likely non-soluble, non-volatile, and is not likely to migrate. This product is described in the Material Safety Data Sheet as being biodegradable. Because of its low viscosity, it would probably not pos a threat to the environment, however, the California Regional Water Quality Control Board, Region 7, recommended that the product should be set back from water courses, storm drains, and drainage ditches. It was also stressed that the product be applied with as little runoff as possible. A slight concentration of Total Organic Carbons appeared in the UBIX 10 sample of 10 ppm. UBIX 10 is described as not having any organic solvents. This trace of organics may have appeared from the wood fibers that were tested on the same test pad as the UBIX 10 treated soil. This low concentration will not pose a significant threat to the environment. 7.4 MATERIAL SAFETY DATA SHEETS Product components compiled from the Material Safety Data Sheets are summarized in Table 14. According to the provided MSDS, none of the products are classified as restricted by the Department of Transportation and International Air Transport Association. Also, none of the products are classified as having toxic chemicals present in quantities greater than the �de minimus� levels. The following is summarized from the MSDS: 1. All products should be kept out of municipal and open bodies of water 2. Insure adequate ventilation when applying product. 3. Products placed in storage should be kept from freezing at 32 degrees Fahrenheit. Temperatures and below 120 degrees Fahrenheit. 4. Protective equipment should be used when applying product. 5. The polymer products yield trace amounts of individual, residual monomers under thermal decomposition. 8. CONCLUSION Based on the results of testing using simulated wheel loading on soils treated with the dust suppressants and the field application the following conclusions can be made:

• The test wheel apparatus and dust collection system is a quantitative, expedient, and repeatable device that can be used for comparing dust suppressant products. The test wheel can be used as a tool to develop the most appropriate technique and application rate of a specific product on a specific soil.

• Dust measurement data from the test beds indicate that dust suppression products can significantly reduce dust generation.

• Of the six products tested, the polymer products, Envirotac II and Soil Sement were most effective for suppressing dust.

• Envirotac II from Environmental Products was the most effective duct control product, showing a 97% improvement over the untreated baseline.

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• Soil Sement of Midwest Industrial Supply was the second most effective dust control product, showing a 90% improvement over the untreated baseline.

• Asphotac did not provide enough dust suppression in the test bed to warrant further consideration, this poor performance is most likely due to the high pH soil found at MCAGCC. The product representative noted that the product may not work well in soil having a high pH.

• The UBIX 10 was not as effective as the polymer products for controlling dust. Unconfined soil tests demonstrated some soil strengthening characteristics. The volume of product used is approximately 1/10 the volume of the polymer used, but considerable effort is required to apply this product.

• The residual wood fibers were effective in minimizing the amount of dust particles generated during bench scale testing. However, there was a considerable amount of wood fiber released into the surrounding area and collected in the filter. A lack of resistance to rutting, dislodgment, and wood fiber deflation under normal foot traffic would make the product unsatisfactory as a dust control measure at MCAGCC.

• Dustrol material from Canada did not cure in a reasonable amount of time. It was concluded that the product was subject to temperatures less than 32 F. The material did not fully cure until three weeks after application. The product is also 5 times more expensive than the polymers and is more labor intensive to apply.

• The application technique is critical to the dust control performance and appearance of roadways.

• None of the products tested have contaminant levels exceeding the TCLP limits, and none pose a risk to health and the environment, or are considered a hazardous waste if removed.

• The polymer products penetrated the soil at a similar rate under identical soil conditions, type, and compaction.

• Soil Sement and Envirotac II produced the least amount of rutting during bench-scale testing. When comparing Soil Sement and Envirotac II in the field application, Envirotac II did not acquire as much rutting or surface pealing as Soil Sement.

• Envirotac II did not spall or crack as readily as the Soil Sement. • Data shows there is a direct correlation between unconfined soil compaction

strength and product effectiveness for controlling dust. • Economic review indicates that chemical stabilizers including polymers proved to

be cost competitive to more conventional means. 9. RECOMMENDATION Based on this test and evaluation effort, the following recommendations are provided:

• Continue monitoring performance of Envirotac II and Soil Sement on Range Range Road over the course of 1½ years. Apply a maintenance coat yearly.

• For unpaved roadways with rubber tired vehicle traffic, and open areas, use acrylic polymer products such as Envirotac II or Soil Sement.

• Determine optimum techniques for repairing potholes developed in treating soils.

29

• Include specification for insuring minimum product penetration in contracts developed for applying the product.

• Use unconfined compression strength test as an inexpensive method for screening dust control products that function on surface hardening.

• Use test beds to determine the optimum methods and the application rates of product for a given soil type.

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REFERENCES Addo, Jonathan Q. and Thomas G. Sanders, Effectiveness and Environmental Impact of Road Dust Suppressants, Mountain-Plains Consortium, Colorado State Univ., Fort Collins, Colorado, March 1995. Atkinson, John, An Introduction to the Mechanics of Soils and Foundations, McGraw-Hill Book Co., San Francisco, 1993. Cleghorn, H.P., Dust Control and Compaction of Unpaved Roads – Field Trials, Ministry of Transportation, R&D Branch, Report No. MAT-92-02, February 1992. Dibblee, T.W. Jr., 1967 Geologic Map of the Deadman Lake Quadrangle San Bernardino County, California: United States Geological Survey Miscellaneous Geologic Investigations Map I-488, scale 1:62, 500. Gebhart, Dr. Dick L. and Mr. Thomas A. Hale, Dust Control Material Performance on Unsurfaced Roadways and Tank Trails, United States Army Environmental Center and United States Army Environmental Center, Technical Report No. SFIM-AEC-ET-CR-96196, Aberdeen Proving Ground, September 1996. Holtz, Robert D., William D. Kovacs, An Introduction to Geotechnical Engineering, Prentice-Hall, Inc., New Jersey, 1981. Lambe, William T., Soil Testing for Engineers, John Wiley & Sons, New York, 1951. Liu Cheng, Jack B. Evett, Soil Properties Testing, Measurement and Evaluation, 2nd ed., Prentice-Hall, Inc., New Jersey, 1990. California Military Installations Map, 1988: Marine Corps Air Ground Combat Center, Twentynine Palms West: Defense Mapping Agency, Hydrographic/Topographic Center, Washington D.C. Sheet, DMA stock no. V795S29PALMSW, scale 1:50, 000. United States Department of Agriculture, Natural Resources Conservation Service, MCAGCC soil Survey at 29 Palms #699, Exhibit #2, 22-26 July, 1996. Watson, John G., Judith Chow, John A. Gillies, H. Moonsmuller, C. Fred Rogers, David DuBois, Jerry Derby, Effectiveness Demonstration of Fugitive Dust Control Methods for Public Unpaved Roads and Unpaved Shoulders on Paved Roads, Desert Research Institute, Reno, Nevada, December 31, 1996.

31

Table 1. Dust Suppression Test Products Product Name Surface

Binders/hardeners Soil

Stabilizers Particle

Adherence Membrane/Surface

Covers Asphotac* X Dewatered Residual Wood Fiber*

X

Envirotac II* X Penzsuppress X Soil Sement* X Dustrol (Tall Oil)* X

EnviroPolymer (Soil Sement) X

Polymer Enzyme X

Ubix X

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Table 2. Summary of Product Application Product Name

Time to Apply (See Note 1)

Volume of Product Used

Volume of Water Used

Equipment Requirements

Notes

Soil Sement < 5 min. 3.6 gallons 30 gallons Sprayer & Compactor

Several minutes (30-40 min.) required for product to penetrate between coats. (3 coats)

Envirotac II < 5 min. 3.5 gallons 28 gallons Sprayer & Compactor

Several minutes (30-40 min.) required for product to penetrate between coats. (2 coats)

Asphotac > 1.5 hrs 3 gallons 12 gallons Sprayer 3 coats applied with manual sprayer.

Dewater Residual Wood Fiber (DRWF)

15 min. 1/3 cubic yard 5 gallons Rake, roller &

Compactor

Product would normally be applied with a walking floor truck

Dustrol (See Note 2) 30 min. 15 gallons 0 gallons Sprayer

Product separation occurred within containers. Two liquid states; one a milky consistency and other like a thick batter. Dustrol required days to cure.

Ubix 1 hr < 1 pint 30 gallons Sprayer,

Rototiller & Compactor

Water was applied to soil until just below optimum moisture content.

Baseline < 5 min. None 20 gallons Compactor Water was applied below optimum moisture content.

Note 1. With the exception of the dewatered residual wood fiber and Ubix, application time can be considered equal if using the same spray devise. Note 2. Dustrol had not cured after seven days.

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Table 3. Winter Test (28 days after product application) Product Name

Captured Dust Particles (mg)

Average Measured Deflection (cm)

Envirotac II 16.3/4hrs (Note1) 0.04 Soil Sement 514/4hrs (Note 1) 0.31 Dewatered Residual Wood Fiber

1770/2hrs (Note 2) 2.10

Asphotac 3794/2hrs 2.14 Ubix (Note 3) See note 1 Dustrol (Note 4) See note 3 Baseline 4658/2hrs 1.28

Note 1. Since both products had substantially less dust capture than the baseline after a visual inspection of the filter at two hours, their run times were doubled Note 2. DWRF was dislodged under normal foot traffic upon setup of the ventilation system. Once dislodged, winds carried the product from its respective test bed. Note 3. Product was not applied until spring since ambient temperatures were below curing temperature. Note 4. Product did not cure within 2 weeks after application. Performance testing of this product was aborted.

Table 4. Spring and Summer Test Product Name

Captured Dust

Particles (mg)

Average Measured Deflection

(cm)

Captured Dust

Particles (mg)

Average Measured Deflection

(cm) Envirotac II 349/4hrs 0.04 128.8/2hrs 0.04 Soil Sement 563.5/4hrs 0.06 481.7/2hrs 0.045 Ubix 1471.7/2hrs 0.425 Note 1 Note 1

Note 1. Ubix was applied as a courtesy to AGSE to determine if it is comparable to the polymer products. Since dust capture was relatively high compared to the polymers and it was not exposed to the same weathering of the polymers Ubix was excluded from summer testing. However, when compared to the baseline performed in the winter Ubix showed substantial improvement.

Table 5. Unconfined Compression Test Data Product Name Force at

Failure (lb) Force at

Failure (lb) Average

Envirotac II 2246 2110 2178 Soil Sement 1610 1396 1503 Tall Oil 1060 650 855 Ubix 536 * 536 Baseline * * * DWRF ** ** **

* Denotes samples that had broken apart during the canister removal. ** Dewatered residual wood fibers were not tested in compression because the application of the product is not designed to change the compressive strength of the soil.

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Table 6. Product Performance on Field Test Sections Envirotac II Soil Sement 4 Days 28 Days 4 Days 28 Days Dust Suppression 10 9 10 9 Rutting 9 8 9 7 Surface Finish 8 8 7 6 Surface Separation 8 7 7 6

Table 7. Cost Comparison of Dust Control Alternatives Costs (per square foot) Alternatives

Soil Preparation

Initial Application

Annual Maintenance

Asphalt Roadway1

$0.23 (Mat) $0.18 (Lab) $0.41 (Tot)

$0.43 (Mat) $0.15 (Lab) $0.58 (Tot)

$0

Chemical Stabilizers2

$0

$0.06 (Mat) $0.02 (Lab) $0.08 (Tot)

$0.05 (Mat) $0.01 (Lab) $0.06 (Tot)

Cement Stabilization3

$0

$0.29 (Mat) $0.0 (Lab) $0.29 (Tot)

$0

Water Application4

$0

$0.005 (Mat) $0.00 (Lab) $0.005 (Tot)

$0.10 (Mat) $0.00 (Lab) $0.10 (Tot)

1 Values obtained from estimator�s handbook. 2 Values obtained from vendor quotes. 3 Values based solely on material cost. 4 Values derived from fuel, water, and pumping costs.

Table 8. Cost Evaluation of Top Performing Chemical Stabilizers Soil Prep

Initial Application (per sq ft)

Annual Maintenance (per sq ft)

Product

Total Material Labor Total Material Labor Total Envirotac

II $0 $0.05 $0.03 $0.08 $0.02 $0.01 $0.03

Soil Sement $0 $0.053 $0.013 $0.065 $0.026 $0.00 $0.033

Values obtained from vendor quotes

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Table 9. Dust Suppression Alternatives Cost Analysis (per square foot) Year

(Cumulative) Envirotac

II Soil

Sement Asphalt Cement

Stabilization Water

Application 0 $0.08 $0.07 $0.99 $0.29 $0.00 1 $0.11 $0.10 $0.99 $0.29 $0.10 2 $0.14 $0.13 $0.99 $0.29 $0.20 3 $0.17 $0.16 $0.99 $0.29 $0.30 4 $0.20 $0.20 $0.99 $0.58 $0.40 5 $0.23 $0.23 $0.99 $0.58 $0.50 6 $0.26 $0.26 $0.99 $0.58 $0.60 7 $0.29 $0.30 $0.99 $0.58 $0.70

Table 10. Dust Control Alternatives Cost Analysis (per mile of 24ft wide roadway)

Year (Cumulative)

Envirotac II

Soil Sement

Asphalt Cement Stabilization

Water Application

0 $10,138.00 $8,237.00 $125,453.00 $36,749.00 $634.00 1 $13,940.00 $12,419.00 $125,453.00 $36,749.00 $13,306.00 2 $17,742.00 $16,601.00 $125,453.00 $36,749.00 $25,978.00 3 $21,544.00 $20,783.00 $125,453.00 $36,749.00 $38,650.00 4 $25,346.00 $24,965.00 $125,453.00 $73,498.00 $51,322.00 5 $29,148.00 $29,147.00 $125,453.00 $73,498.00 $63,994.00 6 $32,950.00 $33,329.00 $125,453.00 $73,498.00 $76,666.00 7 $36,752.00 $37,511.00 $125,453.00 $73,498.00 $89,338.00

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Table 11. Summary of Analytical Results Test Pads Samples TTLC Metal Analysis Sample

Date Sample Time

Test Pad No.

Product Name

Sample No.

Soil Depth

(in)

Metal Analysis TTLC

(mg/kg)

CAM Limits TTLC

(mg/kg)

4/21/97 1720 1 Soil Sement 1-1 3�

Arsenic, 0.9 Barium, 36 Lead, 1.0 All other, BQL

Arsenic, 500 Barium, 1000 Lead 1000

4/21/97 1745 2 Untreated Soil 2-1 3�

Arsenic, 1.1 Barium, 39 Lead, 2.6 Vanadium, 20 Zinc, 16 All others, BQL

Arsenic, 500 Barium, 1000 Lead 1000 Vanadium, 2400 Zinc, 5000

4/21/97 1730 3 Asphotac 3-1 3�

Arsenic, 1.2 Barium, 39 Lead, 2.0 Vanadium, 22 Zinc, 14 All others, BQL

Arsenic, 500 Barium, 1000 Lead 1000 Vanadium, 2400 Zinc, 5000

4/21/97 1630 4 UBIX 10 4-1 3�

Arsenic, 1.2 Barium, 40 Chromium, 4 Lead, 1.9 Vanadium, 21 Zinc, 19 All others, BQL

Arsenic, 500 Barium, 1000 Lead 1000 Vanadium, 2400 Zinc, 5000

4/21/97 1740 5 Envirotac II 5-1 3�

Arsenic, 0.9 Barium, 38 Lead, 1.2 Vanadium, 22 Zinc, 14 All others, BQL

Arsenic, 500 Barium, 1000 Lead 1000 Vanadium, 2400 Zinc, 5000

Notes: BQL=Below Quantifiable Limits

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Table 12. Summary of Analytical Results Test Pads Samples STLC Metal Analysis Sample

Date Sample Time

Test Pad No.

Product Name

Sample No.

Soil Depth

(in)

Metal Analysis

STLC (mg/kg)

CAM Limits STLC

(mg/kg)

4/21/97 1720 1 Soil Sement 1-1 3�

Barium, 2.2 Lead, 0.09 All other, BQL

Barium, 100 Lead, 5

4/21/97 1745 2 Untreated Soil 2-1 3�

Barium, 3.1 Lead, 0.1 Zinc, 0.67 All others, BQL

Barium, 100 Lead 5 Zinc, 250

4/21/97 1730 3 Asphotac 3-1 3�

Barium, 3.2 Lead, 0.09 Zinc, 0.75 All others, BQL

Barium, 100 Lead 5 Zinc, 250

4/21/97 1630 4 UBIX 10 4-1 3�

Barium, 3.9 Zinc, 0.6 All others, BQL

Barium, 1000 Zinc, 250

4/21/97 1740 5 Envirotac II 5-1 3�

Barium, 2.2 Lead, 0.09 All others, BQL

Barium, 1000 Lead, 5

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Table 13. Summary of Analytical Results Test Pads Samples Total Organic Carbons Sample

Date Sample Time

Test Pad No.

Product Name

Sample No.

Soil Depth

(in)

Total Organic Carbons (mg/kg)

4/21/97 1720 1 Soil Sement 1-1 3� BQL

4/21/97 1745 2 Untreated Soil 2-1 3� BQL

4/21/97 1730 3 Asphotac 3-1 3� 650 4/21/97 1630 4 UBIX 10 4-1 3� 10

4/21/97 1740 5 Envirotac II 5-1 3� BQL

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Table 14. Summary of Product Components Envirotac II Soil

Sement Asphotac Dustrol EX UBIX No.

0010 Dewatered

Wood Fibers

Acrylic Polymer 39-43%

Acrylic & Vinyl

Acetate Polymer 5-50%

Petroleum Asphalt (fumes) <60%

Fatty Acids (e.g. Oleic)

20-25%

Enzymes co-enzymes

Carbon 23.94%

Individual Residual

Monomers <0.1%

Water 95-50%

Additives <4%

Rosin Acids (e.g. Abietic)

15-20% Binders Wood Ash

10.85%

Aqua Ammonia

<1.0%

Water none

established

Unsaponifiables Neutrals

(e.g. β-sitosterol) 8-12%

Catalysts Hydrogen 2.99%

Formaldehyde <0.1% Water

50% Watering Agents

Sodium as Na2O

0.816%

Surfactants Potassium

as K2O 0.5211%

Water Nitrogen 0.13%

Water 43%

Remainder

(Inert Ingredients)

40