Chapter 5: Hazardous Waste Site Clean-Up Technologies IN THIS CHAPTER Treatment technologies for contaminated hazardous waste sites Containment technologies for contaminated sites Innovative technologies for contaminated sites Case studies As discussed in Chapter 1, "Introduction to Hazardous Waste", the Toxic Waste Actalso called Superfundis a federal law of the United States that was created to enforce the investigation and cleanup of deserted hazardous waste sites. The contamination from these deserted sites is often below ground, and the hazardous wastes and other pollutants are not as easily accessible as wastes generated at typical industries. Therefore, the technologies used to treat or otherwise manage these wastes are different from conventional technologies. Some technologies have been developed to treat waste where it is found; other technologies have been developed to treat contaminated media once it is brought to the surface. Additionally, for the sites where neither type of these technologies is available, there are management methods to keep the waste from migrating off site. Several examples of each technology are discussed in this chapter. A number of the descriptions of the technologies discussed in this chapter were adapted from a USEPA Superfund Web site, USEPA Superfund Remediation Technologies, athttp://www.epa.gov/superfund/remedytech/remed.htm. This Web page provides individual links to further information about each of the technologies listed below. 5.1 TREATMENT TECHNOLOGIES FOR CONTAMINATED HAZARDOUS WASTE SITES Although all of the technologies discussed in Chapter 4, "Hazardous Waste Treatment and Disposal", are sometimes used for cleanup or "remediation" of inactive hazardous waste sites, there are several additional, specialized technologies that have been employed or are currently in use almost exclusively at cleanup sites. These specialized technologies are necessary when the contamination is trapped underground in groundwater or rock and soil matrices and cannot be reached for conventional treatment. This chapter is devoted to describing a number of cleanup technologies that are available and are used in the United States today. This is not necessarily a complete list, but most of the popular technologies are represented. The technologies discussed in this chapter are grouped into two general classifications of treatment for hazardous waste cleanup sites: in-situ treatment may be defined as the treatment of contaminants prior to their removal from the soil and groundwater; ex-situ treatment involves removing the contaminant from its existing location and treating it above the surface. In-Situ (On-Site) Treatment of Contaminated Hazardous Waste Sites In-Situ Air Entrainment One method used to treat hazardous contaminants in the soil or groundwater is to pump air into the contaminated zones. The two methods, air stripping and air sparging, are listed below. Air stripping is the forcing of air through contaminated groundwater or surface water to remove harmful chemicals. This technology is most effective when the groundwater is easily accessible and the contaminants are volatile and/or semi-volatile and easily susceptible to treatment by exposure to air molecules. Air stripping is ineffective if the contaminants are bound to the particles of rock and soil. A schematic of air stripping of media in a vessel is depicted in Figure 5.1. Figure 5.1: Air stripper. (Adapted from EPA 542-F-01-016.) Air sparging involves the injection of air or oxygen through a contaminated soil zone. Injected air traverses in channels through the soil column both horizontally and vertically. This creates an underground stripper that removes volatile and semi-volatile organic compounds by volatilizing these contaminants. Air is injected to help flush the contaminants into the vadose (unsaturated) zone. Sometimes oxygen is added to the contaminated soils to optimize biodegradation both above and below the water table. Air sparging in combination with soil vapor extraction is illustrated inFigure 5.2. Soil Vapor Extraction Soil Vapor Extraction (SVE) can be used as an in-situ or ex-situ Note treatment method and can be used in combination with many other types of treatments. SVE is used to remove contaminants from unsaturated (vadose) zone soils. A vacuum is applied to the soil to facilitate the controlled flow of air, removing volatile and some semivolatile organic contaminants from the soil. SVE usually is performed in-situ; however, in some cases, it can be used as an exsitu technology. (Any vapor treated after removal is treated in an exsitu process.) Figure 5.2: Air sparging using SVE. (Adapted from EPA 510-B-95-007.) In-Situ Bioremediation Bioremediation is a broad term that connotes using microbes to clean up harmful chemicals in contaminated media. This technology is possible only if the proper amounts of oxygen and nutrients are available at appropriate temperatures. Bioremediation is most effective when the contaminants are consistent, and the temperature and other environmental factors are steadystate. In-situ bioremediation techniques create and stimulate a favorable environment for microorganisms to grow and use various contaminants as a food and/or energy source. The treatment is effective only when the proper combination of oxygen, nutrients, and moisture are provided, attendant with temperature and pH control. Sometimes, microorganisms that have been adapted for degradation of specific contaminants are applied to enhance the process. Two examples of bioremediation are given below: Bioremediation of chlorinated solvents "uses microorganisms to break down contaminants by using them as a food source or by cometabolizing them with a food source. Aerobic processes require an oxygen source, and the end products typically are carbon dioxide and water. Anaerobic processes are conducted in the absence of oxygen, and the end products can include methane, hydrogen gas, sulfide, elemental sulfur, and dinitrogen (N2) gas" [EPA 11h]. Chemical oxidation involves pumping chemicals called oxidants down into wells to destroy pollution in soil and groundwater. Oxidants react with harmful chemicals to reduce them to harmless ones, like water and carbon dioxide. Chemical oxidation is used to treat many chemicals such as fuels, solvents and chemicals [EPA 11h]. In-Situ Physical Treatment There are a number of physical treatment technologies used for cleanup: Soil excavation is arguably not a treatment; however, digging up polluted soils in order for them to be placed in a permitted landfill is necessary when no other effective or practical form of treatment is available. Pump and treat is a method that uses pumps to bring contaminated liquids up to the surface, where the liquids are either treated and discharged or taken off site for treatment. Fracturing uses a liquid or air to fracture rocks or dense soils in order to enable other types of treatment. As with soil excavation, fracturing is not a treatment in and of itself. In-situ flushing is the process of pumping uncontaminated, harmless liquids into wells to push contaminated liquids underground toward recovery wells. (These liquids can then be pumped to the surface for treatment in an ex-situ process.) Permitting is not usually an issue for hazardous waste cleanups Note because they are not ordinarily required to obtain a hazardous waste permit. Facilities set up to treat wastes generated at hazardous waste clean-up sites are exempt from hazardous waste permitting provided they meet the Applicable or Relevant and Appropriate Requirements (ARARs). These requirements are spelled out in the Superfund Law (CERCLA), which was discussed in Chapter 1, "A Brief History of Hazardous Waste", In-Situ Thermal Treatment This treatment method uses several means of thermal elevation of soils to destroy contaminated soils and liquids or to push them toward collection wells. Often, combinations of thermal treatment that include thermal conduction, electrical resistance, steam, hot air, hot water, or radio frequency, are used. Thermal treatment is very effective on nonaqueous phase liquids (NAPL), which do not migrate or dissolve easily in groundwater. (Materials removed by this process are then treated in an ex-situ process such as wastewater treatment.) Multiphase extraction uses a powerful vacuum system to remove subsurface contaminants such as groundwater, vapors, and petroleum product. This lowers the water table around the well, exposing more of the contamination in the formation. These contaminants in the exposed vadose zone are then more accessible to SVE. Once above ground, the extracted vapors or liquid-phase organics and groundwater are separated and treated ex-situ, usually by wastewater treatment. Phytoremediation uses plants and trees to treat contaminated soils. The roots of the plants take up the contaminated liquids and use them as nutrients. This process converts some of those chemicals into less hazardous ones. The roots of the plants also significantly reduce erosion caused by wind and precipitation. This type of treatment works only in climates appropriate for the plants and on chemicals that are not toxic to the plants. Monitored natural attenuation uses natural conditions and naturally occurring bacteria that are already present to clean up contaminants. Conditions are monitored to make sure they are amenable for the natural treatment to occur. Permeable reactive barriers are underground walls filled with permeable, reactive material, arranged in a long narrow trench. The reactive material treats the contaminated liquids as they migrate through the wall, sometimes pushed through the barrier by pumping nonhazardous liquids into wells that are located along one side of the wall. An illustration of a permeable reactive barrier is shown in Figure 5.3. "Circulating wells (CWs) provide a technique for subsurface remediation by creating a three-dimensional circulation pattern of the ground water. Groundwater is drawn into a well through one screened section and is pumped through the well to a second screened section where it is reintroduced to the aquifer. The flow direction through the well can be specified as either upward or downward to accommodate site-specific conditions. Because groundwater is not pumped above ground, pumping costs and permitting issues are reduced and eliminated, respectively. Also, the problems associated with storage and discharge are removed. In addition to groundwater treatment, CW systems can provide simultaneous vadose zone treatment in the form of bioventing or soil vapor extraction. CW systems can provide treatment inside the well, in the aquifer, or a combination of both. For effective in-well treatment, the contaminants must be adequately soluble and mobile so they can be transported by the circulating ground water. Because CW systems provide a wide range of treatment options, they provide some degree offlexibility to a remediation effort" [EPA 11h]. Figure 5.3: Permeable reactive barrier. (Adapted from EPA/600/R98/125.) "Electrokinetics relies upon application of a low-intensity direct current through the soil between ceramic electrodes that are divided into a cathode array and an anode array. This mobilizes charged species, causing ions and water to move toward the electrodes. Metal ions, ammonium ions, and positively charged organic compounds move toward the cathode. Anions such as chloride, cyanide, fluoride, nitrate, and negatively charged organic compounds move toward the anode. Removal of contaminants at the electrode may be accomplished by several means, among which are: electroplating at the electrode; precipitation or coprecipitation at the electrode; pumping of water near the electrode; or complexing with ion exchange resins" [EPA 11h]. Ex-Situ (Off-Site) Remediation Examples of off-site remediation (contaminants or contaminated media brought to the surface for treatment at the cleanup site or at a facility removed from the site) include: Ex-Situ Bioremediation Slurry-phase bioremediation mixes excavated contaminated soils in water to form a slurry. This slurry keeps solids suspended and microorganisms in contact with the soil contaminants, thus facilitating treatment. Solid-phase bioremediation mixes added water and nutrients with soils, which are then placed in a cell or building. Examples of ex-situ, solidphase bioremediation are land farming and composting. Ex-Situ Physical/Chemical Treatment Each of the methods listed below is used to treat contaminants after they have been brought to the surface of the contaminated site. Ex-situ chemical dehalogenation involves the digging, sifting, and crushing of soils contaminated with halogens (chlorine, bromine, iodine, and fluorine). These soils are then placed in an on-site reactor with heat and specific chemicals to reduce the halogen content or to change the chemicals to less hazardous ones. There are two types of chemical dehalogenation: 1. "Glycolate dehalogenation adds a combination of two chemicals known as alkaline polyethylene glycol (APEG) to soil in a reactor similar to the one described above. During mixing and heating, one chemical combines with the halogens to form a nontoxic salt. The other replaces the halogens to form other nontoxic chemicals. The heat in the reactor can cause some of the chemicals to evaporate. The gases are treated by air pollution control equipment at the site" [EPA 11h]. 2. Base-catalyzed decomposition is a process in which contaminated soil is excavated and "sodium bicarbonate is added to the soil in the reactor. The sodium bicarbonate allows the harmful chemicals in the soil to evaporate at a low temperature. Once the chemicals evaporate, the cleaned soil can be returned to the site" [EPA 11h]. "Solvent extraction uses an organic solvent to separate organic and metal contaminants from soil. First, the organic solvent is mixed with contaminated soil in an extraction unit. The extracted solution then is passed through a separator, where the contaminants and extractant are separated from the soil. Organically bound metals may be extracted along with the target organic contaminants" [EPA 11h]. (Although the extraction is sometimes an in-situ process, any treatment of these extracted materials is classified as ex-situ.) Soil washing is a process where contaminants adsorbed "onto fine soil particles are separated from bulk soil in a water-based system on the basis of particle size. The wash water may be augmented with a basic leaching agent, surfactant, or chelating agent or by adjustment of pH to help remove organics and heavy metals. Soils and wash water are mixed ex-situ in a tank or other treatment unit. The wash water and various soil fractions are usually separated using gravity settling" [EPA 11h]. Bioreactor landfills operate "to rapidly transform and degrade organic waste. The increase in waste degradation and stabilization is accomplished through the addition of liquid and air to enhance microbial processes. This bioreactor concept differs from the traditional 'dry tomb' municipal landfill approach. A bioreactor landfill is not just a single design and will correspond to the operational process invoked. There are three different general types of bioreactor landfill configurations: 1. AerobicLiquid leachate is removed from the bottom layer, piped to liquids storage tanks, and recirculated into the landfill in a controlled manner. Air is injected into the waste mass, using vertical or horizontal wells, to promote aerobic activity and accelerate waste stabilization. 2. AnaerobicMoisture is added to the waste mass in the form of recirculated leachate and other sources to obtain optimal moisture levels. Biodegradation occurs in the absence of oxygen (anaerobically) and produces landfill gas. Landfill gas, primarily methane, can be captured to minimize greenhouse gas emissions and for energy recovery projects. 3. Hybrid (Aerobic-Anaerobic)The hybrid bioreactor landfill accelerates waste degradation by employing a sequential aerobic-anaerobic treatment to rapidly degrade organics in the upper sections of the landfill and collect gas from lower sections" [EPA 11h]. Ex-Situ Thermal Treatment This method "generally involves the destruction or removal of contaminants through exposure to high temperature in treatment cells, combustion chambers, or other means used to contain the contaminated media during the remediation process. The main advantage of ex-situ treatments is that they generally require shorter time periods, and there is more certainty about the uniformity of treatment because of the ability to screen, homogenize, and continuously mix the contaminated media; however, ex-situ processes require excavation of soils, which increases costs and engineering for equipment, permitting, and materials handling worker safety issues" [EPA 11h]. These processes use heat to separate, destroy, or immobilize contaminants. Pyrolysis and conventional incineration destroy the contaminants. "Pyrolysis is defined as chemical decomposition induced in organic materials by heat in the absence of oxygen. Pyrolysis typically occurs under pressure and at operating temperatures above 430C (800F). The pyrolysis gases require further treatment. The target contaminant groups for pyrolysis are semivolatile organic compounds (SVOCs) and pesticides. The process is applicable for the separation of organics from refinery wastes, coal tar wastes, wood-treating wastes, creosote-contaminated soils, hydrocarbon-contaminated soils, mixed (radioactive and hazardous) wastes, synthetic rubber processing wastes, and paint waste" [EPA 11h]. Incineration is an ex-situ, heat-based technology that has been used for many years to burn and destroy contaminated materials. There are several types of incinerators discussed in Chapter 4. Thermal desorption and hot gas decontamination are two processes that separate the contaminants from the media to which they are attached. "Thermal desorption involves the application of heat to excavated wastes to volatilize organic contaminants and water. Typically, a carrier gas or vacuum system transports the volatilized water and organics to a treatment system, such as a thermal oxidation or recovery unit. Based on the operating temperature of the desorber, thermal desorption processes can be categorized as either high-temperature thermal desorption (320 to 560C or 600 to 1,000F) or low-temperature thermal desorption (90 to 320C or 200 to 600F)" [EPA 11h]. A parallel flow (co-current) rotary lowtemperature thermal desorption system is illustrated in Figure 5.4. Figure 5.4: Thermal desorption system. (Adapted from EPA 510-B95-007.) "Hot gas decontamination involves raising the temperature of contaminated solid material or equipment to 260C (500F) for a specified period of time. The gas effluent from the material is treated in an afterburner system to destroy all volatilized contaminants. This method will permit reuse or disposal of scrap as nonhazardous material. Other thermal technologies include: Vitrification technology uses an electric current to melt contaminated soil at elevated temperatures (1,600 to 2,000C or 2,900 to 3,650F). Upon cooling, the vitrification product is a chemically stable, leach-resistant, glass and crystalline material similar to obsidian or basalt rock. The high temperature component of the process destroys or removes organic materials. Radionuclides and most heavy metals are retained within the vitrified product. Vitrification can be conducted in-situ or ex-situ. Thermal off-gas treatment is one of several approaches that can be used to cleanse the off-gases generated from primary treatment technologies, such as air stripping and soil vapor extraction. In addition to the established thermal treatments, organic contaminants in gaseous form can be destroyed using innovative or emerging technologies, such as alkali bed reactors. Plasma high temperature recovery uses a thermal treatment process applied to solids and soils that purges contaminants as metal fumes and organic vapors. The vapors can be burned as fuel, and the metals can be recovered and recycled" [EPA 11h]. 5.2 CONTAINMENT OF CONTAMINANTS IN PLACE Although the methods mentioned below might be considered in-situ, they are really neither in-situ nor ex-situ treatment because they are designed to confine, rather than treat, the contaminants in their current location. Capping: Placing a cover over contaminated materials to keep them from spreading to other areas because of precipitation, wind, or physical contact by humans or animals. Groundwater Cutoff/Containment Wall: This involves digging a trench around the contaminated media to prevent the migration of contaminants from the site. The material used is impermeable, such as concrete, a clay slurry, or a plastic barrier. Solidification/Stabilization: This method is used to stabilize contaminated media that is difficult to treat by other means. Both methods are used to bind the contaminants in the soil to keep them from migrating off site, or to make them safe to dispose as landfill. 5.3 INNOVATIVE CLEAN-UP TECHNOLOGIES The USEPA Web site at http://www.cluin.info/products/nairt/overview.cfm provides access to a report on innovative remediation technologies. The Field-Scale Demonstration Projects in North America, 2nd Edition, Year 2000 Report [EPA 00] is a revision and expansion of the 1996 USEPA publication,Completed North American Innovative Technology Demonstration Projects (http://www.epa.gov/oust/cat/demorept.pdf). The project information in the year 2000 document is now available in an online, searchable database of ongoing and completed field demonstrations of innovative remediation technologies; it is sponsored by government agencies working in partnership with private technology developers to bring new technologies into the hazardous waste remediation marketplace. The Field-Scale Demonstration Projects in North America report Note (2000) is available at http://www.cluin.org/download/remed/nairt_2000.pdf [EPA 00]. This database contains projects through June 2000 only. Current demonstration project information is available in the separate Remediation Technology Demonstration Project Profiles database. [EPA 10] Nanotechnology in Clean-Up Situations Nanotechnology is a physical treatment that is accomplished at an incredibly small scale, and through which the materials can be manipulated to accomplish a particular purposein this case, the treatment of hazardous contaminants. A nanometer is one billionth of a meterabout one ten-thousandth the thickness of a human hair. Because the particles are very small compared to the contaminant particles, nanotechnology allows faster and more complete penetration of the nanoscale materials into the contaminants. Also, because the surface areas of the nanoparticles are very large when compared with their volumes, their reactivity in surface reactions can be much more effective compared with the same material at much larger sizes. One big advantage of nanoscale materials is that they can be manipulated to create novel properties not present in particles of the same material at the microor macro-scale. Nanoscale materials may also exhibit altered reaction rates that cannot be explained by surface-area alone. These properties can provide enhanced contaminant contact, causing rapid reduction of contaminant concentrations. An EPA Web site describes several success stories and an overview of the potential and current uses of nanotechnology [EPA 11i]. Some of the clean-up technologies listed in this chapter require air Note pollution control technologies and/or water pollution control technologies to be applied, because some of these treatment technologies cause the release of contaminants into the air or surface of water. Chapter 6, "Air Pollution Control", describes basic air pollution technologies and their application to hazardous waste streams, and Chapter 7, "Wastewater Management", does the same for wastewater treatment technologies. Although not addressed in detail in this book, federal and state air and water pollution regulations apply to many forms of hazardous waste treatment. For further information, contact the state regulatory authority in the state where the cleanup is located. 5.4 CASE STUDIES The following case study is an example of the problems associated with a company that containerizes and sells compressed gases. Case Study Compressed Gas Facility Going Out of Business A hazardous waste inspector received a notice from the U.S. Food and Drug Administration (USFDA) that a business that supplied medical oxygen was temporarily suspended from selling containerized oxygen because of various health violations. The inspector visited the site to see if there were any waste compressed gases on site that needed to be properly disposed. The business owner was in poor health, and although he clearly wanted to comply with the corrections mandated by the FDA, he was unable to do so, and the oxygen supply business failed. The owner had stated that medical oxygen supply was the mainstay of his compressed gas business, so his inability to keep the oxygen business caused concern about the fate of the remaining compressed gas cylinders on site. In an on-site inventory, the inspector discovered over one thousand compressed gas cylinders, many of which were visibly corroded; some were stored in trailers and other buildings on and off site. As discussed in Chapter 2, "Identification of Hazardous Waste", waste compressed gases with pressure over 1 atmosphere, that are flammable or that will support combustion, are D001 hazardous waste. There were hundreds of oxygen and acetylene cylinders scattered throughout the property, because the facility refilled these cylinders for welders throughout the area. There were cylinders of nonhazardous gases such as nitrogen, argon, and freon, together with some fairly uncommon gases. The most poisonous gas found on site was phosgene, a gas that was used as a nerve agent in World War I, but that is still used as a reagent in the pharmaceutical industry today. Of even greater concern were other types of compressed gases that were unstable or even explosive. One example of these is hydrogen gas, highly explosive at room temperature and pressure. Another potentially unstable and explosive gas is contained in old acetylene containers. If acetylene gas is pressurized in its pure form over 15 PSI, it breaks down or separates into carbon black and hydrogen gas, a highly unstable and explosive mixture. If acetylene gas is placed in a container with a fabric "wick" containing a solvent such as benzene or acetone in the center of the tank, it is stable up to 1500 PSI. A serious problem can arise if the acetylene cylinder is stored for a long period, because the solvent that stabilizes the gas can diffuse out of the wick and container, leaving a very unstable, explosive container. When the business shut down a few weeks later, the facility manager vented all of the dangerous containers on site (except for the poisonous gases). Those empty containers were hauled off site for scrap metal recovery. This incident had a satisfactory ending in that all of the gas cylinders were removed without incident, the building was demolished, and a new business has been built on the same site. The hazardous wastes generated in this case were predominantly D001 (ignitable), but because they were released directly to the environment and they had no measurable weight, after the containers were vented, it was as though the wastes had never been generated. The next case study concerns a company established to recover mercury from hearing aid batteries, switches thermostats, and other mercury-containing equipment, and to sell the recovered mercury for future manufacturing. Case Study Mercury Recovery Facility Creates Federal Clean-Up Site Beginning in 1955, the Mercury Refining Company (MERECO) in upstate New York accepted mercury-containing wastes from batteries, thermometers, dental amalgam, etc., and refined the mercury for resale. The mercury was reclaimed using retort (condensation) furnaces at the facility. This facility was a commercial hazardous waste facility because hazardous waste was received from off site for on-site storage. Before 1980, waste contaminated with mercury was dumped over an embankment of an unnamed tributary to a creek. Contaminated groundwater ran off the site. In 1981, there was a structure fire at the facility, and a large amount of water used for fighting the fire ran off the site. The NYSDEC sampled the area around the tributary and found polychlorinated biphenyls (PCBs) and mercury contamination on the southern edge of the property and the embankment of the tributary. In 1983, the USEPA placed the MERECO site on the National Priorities List of the most contaminated sites in the country. In 1998, MERECO discontinued reclaiming mercury, but continued reclaiming precious metals at the facility. After several interim cleanup and containment actions, in 1999, at the request of the NYSDEC, the USEPA took over as lead agency and initiated and completed a remedial investigation and feasibility study of the site. The final costs for the investigation and cleanup at the site are approximately $11,500,000. Even after the cleanup, residual mercury pollution will remain downstream of MERECO in the Patroon Creek [EPA 11j]. The next case study is about a little-known chemical that becomes highly unstable and explosive when it is stored for a long time. Case Study Picric Acid Found in an Office Building Picric acid [C6H2(NO2)3OH], also known as trinitrophenol, is an unstable acid used primarily as a chemical reagent and as a booster to detonate other, less sensitive explosives, such as TNT (trinitrotoluene). Other uses of picric acid have been as an antiseptic, a yellow dye, and in the synthesis of a powerful insecticide. Picric acid was used in bombs and grenades in World War I. The salts of picric acid can be shock and friction sensitive when this substance becomes crystallized. When a bottle of picric acid is stored for a long time and the acid crystallizes under the cap, an explosion can result from someone simply unscrewing the cover. In one incident, a biological fisheries lab had used the yellow dye property of picric acid to mark the sides of fish during a study. The unused acid was then stored in a one gallon jug in the basement of an office building for several years. When the old bottle was discovered, it was in a shock-sensitive box, supported in all directions by springs. Thankfully, the container was clearly labeled, and the workers inquired about the safety issues before disturbing the container. After inquiring and finding out about the acid's explosive and unstable nature, a specialty waste management company was called in to safely remove the container. This incident ended well; the container was safely removed from the building and was detonated in a safe location. Had the bottle detonated inside the building, the explosive force would have likely caused considerable damage. The hazardous waste generated in this case is D002 (see Table 2.1 in Chapter 2), because picric acid is corrosive, but should also be listed as a (D001) flammable solid. The next study is about a disturbing nationwide trend: the manufacture of methamphetamines (crystal meth) in residences and remote areas. Case Study Methamphetamine Laboratories Hazardous waste inspectors are sometimes asked to visit abandoned methamphetamine (meth) labs to help evaluate the hazardous wastes left behind and to give advice on cleanup. There is a grave danger of explosions and fires occurring at unattended or abandoned meth labs for at least two reasons: Sometimes explosive traps are set by perpetrators running an active lab to prevent intruders from entering the lab. Large amounts of solvent (alcohol and acetone) are used to strip the pseudoephedrine/ephedrine for the formulation of the methamphetamine. Many meth lab explosions are the result of different solvents evaporating, in a poorly ventwilated area, and being exposed to a spark or an open flame. Figure 5.5 displays the types of chemicals found at a methamphetamine lab. Figure 5.5: Chemicals from a methamphetamine lab. (Adapted from EPA-560-F05-232.) The pollution resulting from a meth lab can be very detrimental to the environment, in that when these operations are abandoned, the perpetrators leave behind containers of solvents and other wastes that are often dumped by the owners or otherwise eventually leak into the environment. The hazardous wastes left behind are commonly ignitable (D001) (see Table 2.1) and F-list (see Table 2.2) waste, depending on the exact solvent(s) left behind. The next case study is about a long-abandoned fireworks factory discovered in a wooded area. The cleanup had many tense moments. Case Study Abandoned Fireworks Factory A hazardous waste inspector received an anonymous call that an abandoned fireworks factory had been discovered. When arriving at the site, the inspector discovered a very old concrete building that had once been the fireworks factory, filled with unmarked containers as shown in Figure 5.6. Several old, collapsing sheds, cars, and trucks were scattered around the five-acre property, and the sheds and each vehicle was packed full of old, long-expired fireworks. The abandoned factory was also full of old corroded containers of black gunpowder, wet fireworks, and the materials used to make fireworks. Figure 5.6: Abandoned fireworks factory. (Drawing by author.) The following questions should have been asked for this site: Q: What is the inspector's highest priority? A: Safety. abandoned fireworks are flammable, explosive, and if old or wet, they can be unstable. Q: What types of hazardous wastes might be found on site? A: D001 (Flammable), D003 (reactive), D004-38 (metals) and some F wastes (solvents) Q: What should the inspector do first? A: Stay clear of all fireworks and call the office to tell them what had been found. Q: What should be done next? A: call police or fire department for help in securing the site. Q: Which government agencies would be ultimately responsible for the cleanup? A: Federal emergency Management agency (FEMA), state emergency agency, local police and fire departments, Federal Bureau of alcohol, tobacco and Firearms (ATF), Military Demolition Squad, federal, state and local environmental and health agencies. This situation was real, and the outlined steps were taken. Thankfully, no one was injured during the investigation, removal, transportation, and destruction of the fireworks. After the site was discovered and the environmental agency was contacted, the local fire department and police were called. The federal and state emergency management agencies implemented an emergency management plan, asking for assistance from FEMA, ATF, U.S. Army, USEPA and the state environmental agency. How was it disposed? Under RCRA, these explosive wastes should have been properly packaged and transported to a licensed hazardous waste TSDF and burned. However, given the unstable nature of the waste, and the hazards associated with packaging the wastes, the ATF supervised while the U.S. Army Munitions Unit loaded several dump truck loads of fireworks and materials and transported and burned them in a gravel pit. This case ended without incident, other than the expense to the state for the emergency management measures. Needless to say, it could have ended badly if the abandoned factory had been vandalized, especially by fire. SUMMARY In this chapter, you learned about treatment technologies for contaminated hazardous waste sites, containment technologies for contaminated sites, and a few innovative technologies for contaminated sites. You also read case studies about a compressed gas facility going out of business, a poorly operated mercury recovery facility creating a cleanup site, picric acid in an office building, the dangers of methamphetamine labs, and an abandoned fireworks factory. In the next chapter, you will learn the history of air pollution in the United States, learn about the structure of the atmosphere, study sources of air pollutants, learn classification of air pollutants, study the effects of air pollution, learn air pollution control technologies, read about performance standards for incinerators, study automobile pollution and control technologies, and discover the relationship between air pollution control and hazardous waste. You will also read case studies on complaints by neighbors causing more hazardous waste and air pollution, dry cleaners driven by regulations, and trial burns for hazardous waste combustors. EXERCISES 1. Why do we need specialized remediation or cleanup technologies? 2. What is the difference between in-situ and ex-situ treatment? 3. What is the difference between air stripping and air sparging? 4. What are the requirements for bioremediation to work effectively? 5. Where is soil vapor extraction (SVE) most effective? 6. What conditions are adverse to phytoremediation? 7. Name a few examples of solid-phase bioremediation. 8. What is the main advantage of all bioreactor landfills? 9. What is pyrolysis and how is it used in waste treatment? a. What is one drawback of this technology? 10. Name at least two situations where a containment technology would be necessary at a contaminated hazardous waste site. Answers 1. 2. 3. 4. In-situ treatment is treatment of contaminants without first removing them from the soil, and ex-situ treatment involves removing the contaminants and treating them on the surface. Contaminants of consistent makeup and concentration, steady-state environmental conditions (temperature, soil types, etc.). 5. 6. Harsh climates, chemicals toxic to plants. 7. 8. These landfills rapidly transform and degrade organic waste. 9. 10. Where the contaminants are inaccessible for removal or treatment, or where no know treatment for the waste exists. REFERENCES [EPA 00] USEPA Office of Solid Waste and Emergency Response EPA 542-B-00004 June 2000 (5102G), online at http://www.cluin.org/download/remed/nairt_2000.pdf, (accessed May 20, 2011). [EPA 10] Remediation Technology Demonstration Project Profiles database, last updated June, 2010, online at http://www.cluin.org/products/demos/search/vendor_search.cfm, (accessed May, 20 2011). [EPA 11h] USEPA Superfund Remediation Technologies, available online at http://www.epa.gov/superfund/remedytech/remed.htm, (accessed May, 20 2011). [EPA 11i] USEPA Technology Innovation and Field Services Division, Nanotechnology Applications for Environmental Remediation, online athttp://www.clu-in.org/techfocus/default.focus/sec/Nanotechnology %3A_Applications_for_Environmental_Remediation/cat/Overview/, (accessed May 20, 2011). [EPA 11j] USEPA Region 2 Fact Superfund Facts on Mercury Refining, online at http://www.epa.gov/region2/waste/fsmercur.htm, (accessed May 20,2011). APUS Assignment Graduate Level Rubric EXEMPLARY ACCOMPLISHED DEVELOPING BEGINNNIG LEVEL LEVEL LEVEL LEVEL Student demonstrates proficient command of the subject matter in the assignment. Assignment shows an impressive level of depth of student's ability to relate course content to practical examples and applications. Student provides comprehensive analysis of details, facts, and concepts in a logical sequence. Student exhibits above average usage of subject matter in assignment. Student provides above average ability in relating course content in examples given. Details and facts presented provide an adequate presentation of student's current level of subject matter knowledge. Student tries to explain some concepts, but overlooks critical details. Assignment appears vague or incomplete in various segments. Student presents concepts in isolation, and does not perceive to have a logical sequencing of ideas. 38-40 points 32-37 point The assignment reveals that the student has a general, fundamental understanding of the course material. Whereas, there are areas of some concerning in the linkages provided between facts and supporting statements. Student generally explains concepts, but only meets the minimum requirements in this area. TOTAL POINTS 300-400 CONTENT AND SUBJECT KNOWLEDGE 40/40 24 points and below 25-31 points CRITICAL THINKING SKILLS Student demonstrates a higher-level of critical thinking necessary for 500-600 level work. Learner provides a strategic approach in presenting examples of problem solving or critical thinking, while drawing logical conclusions which are not immediately obvious. Student provides well-supported ideas and reflection with a variety of current and/or world views in the assignment. Student presents a genuine intellectual development of ideas throughout assignment. Student exhibits a good command of critical thinking skills in the presentation of material and supporting statements. Assignment demonstrates the student's above average use of relating concepts by using a variety of factors. Overall, student provides adequate conclusions, with 2 or fewer errors. Student takes a common, conventional approach in guiding the reader through various linkages and connections presented in assignment. However, student presents a limited perspective on key concepts throughout assignment. Student appears to have problems applying information in a problem-solving manner. Student demonstrates beginning understanding of key concepts, but overlooks critical details. Learner is unable to apply information in a problem-solving fashion. Student presents confusing statements and facts in assignment. No evidence or little semblance of critical thinking skills. 30/25refer to the remarks within paper. 14 and under points 21-25 points 20-15 points 26-30 points ORGANIZATIO N OF IDEAS Student thoroughly understands and excels Student explains the majority of points Learner applies some points and concepts Assignment reveals formatting errors and 30/25refer to AND FORMAT/Refere ncing in explaining all major points. An original, unique, and/or imaginative approach to overall ideas, concepts, and findings is presented. Overall format of assignment includes an appropriate introduction (or abstract), welldeveloped paragraphs, and conclusion. Finished assignment demonstrates student's ability to plan and organize research in a logical sequence. Student uses at least of 5-7 references in assignment. 26-30 points TOTAL POINTS and concepts in the assignment. Learner demonstrates a good skill level in formatting and organizing material in assignment. Student presents an above average level of preparedness, with a few formatting errors. Assignment contains less than 5 resources. 21-25 points incorrectly. Student uses a variety of formatting styles, with some inconsistencies throughout the paper. Assignment does not have a continuous pattern of logical sequencing. Student uses less than 3 sources or references. 20-15 points a lack of organization. Student presents an incomplete attempt to provide linkages or explanation of key terms. The lack of appropriate references or source materials demonstrates the student's need for additional help or training in this area. Student needs to review and revise the assignment. 14 and below point the remarks within your paper. Only 2 references