BioCycle October 2004, Vol. 45, No. 10, p. 59
Methods for recycling materials and remediating contaminated soils in the Balkans are applicable to other military operations as well as the civilian community. Preferred methods now emphasize recovery and composting operations.
Major Robert E. Tucker, Major James F. Lee, and Major William R. Gatewood
THE OVERALL OPERATIONS in the Balkans have matured from an initial entry of troops into a war-torn country to the current peaceful, steady state phase of operations. The multinational forces work from established bases that rely on stabilized civilian infrastructure and the host country work force. In this respect, the Army’s approach to solid waste management also has matured. In the initial stage, processes such as burning and/or dumping all types of waste have transitioned into wastewater treatment plants, recycling programs, and composting operations as the preferred methods of waste management practices.
The Deputy Chief of Staff, Engineer (ODCSENGR) environmental program is unlike many other military environmental programs because the entire focus is on supporting the Army mission in a deployed area of operation. The primary components of the ODCSENGR environmental program include waste management, waste reduction, drinking water, pollution prevention, facility baseline studies, and base closure documentation. The Army has been proactive in the environmental field, providing guidance in environmental protection, training and sponsoring research. The Bosnia mission was originally planned to last at most one year when our troops went into the country in December 1995. Thus, a high cost of waste hauling and disposal was not expected to be a significant factor over the time span of the mission. When the mission became more open ended, it was evident that hauling solid waste across international borders would require obtaining Basel Agreements permission with the various countries, which requires time. All the while, wastes accumulated in our base camps.
An additional factor affecting the success of the original waste management plan was that peace has broken out across the Balkans. Citizens have become more concerned about obnoxious smoke from garbage burning operations, heavy trucks on the roads, and environmental issues in general. The need for change was apparent. The ODCSENGR goal is to find more fully evolved techniques and technologies for waste management that are sustainable over time, supportive of current challenges and easily transferable to other U.S. military operations worldwide.
Understanding the waste management challenges of a military base camp requires an understanding of the people who populate the camp. The population is not equitable to a similar sized civilian community. A base population is predominantly young and male, consumes a large amount of food daily, uses approximately 100 gal/day/ person of water (two showers a day), and uses a large amount of consumer goods. All this consumption requires a robust supply system and generates considerable quantities of solid and liquid waste. As an average, about 3,000 personnel were in the Bosnia area of operations and about 5,000 in the Kosovo area.
Several significant issues cropped up with disposing of solid waste. When U.S. forces began initial operations in Bosnia, garbage was dumped in open, unlined pits approved by the local governments. When the Kosovo mission began, the same practices were used. After a Bosnian national was accidentally killed at a dump site trying to retrieve materials from a U.S. operated garbage truck, burning operations began in both Bosnia and Kosovo. The decision was made to secure two small capacity air curtain destructors (dunnage burners) for Bosnia and two slightly larger ones for Kosovo and to operate them inside a controlled access site. These burners would reduce the amount of garbage being dumped by 65 to 75 percent and destroy any value of materials coming from the posts. The amount of wet material, paper, and plastics being burned required significant quantities of accelerants and wood to provide the amount of heat to maintain a hot fire. And of course, the smoke was not the cleanest product, causing complaints from residents and soldiers alike in both operational burning yards.
At the same time, petroleum contaminated soil (PCS) also was becoming a problem. Disposing of this material was expensive, reaching a cost just over $400/cubic meter for one spill. A soil incineration project tried in about 2001was not successful. All the while, PCS was accumulating at the Camp Bondsteel (CBS) base camp in Kosovo. By spring 2003, some 2,000 cubic meters of PCS needed disposal.
Finally, a management solution was needed for the wastewater solids. Initially, most of the biosolids effluent at two percent solids was land applied on berms and off limit areas at Camp Bondsteel. Eventually, the solids were dewatered in a filter press and stored in one cubic meter wooden boxes. For nearly a year, it was stored this way as there was no place to dispose of it, leading to the recognition that a more sustainable management system was needed.
The initial waste management plan to meet these challenges took on a three-prong approach: Focus on the solid waste; Develop a method to remediate PCS; and Determine the best method to manage sewage sludge. The task was to examine different technologies, look at innovative solutions, save money, and complete the process quickly.
SOLID WASTE SURVEY
The premise for solid waste reduction focused first on identifying materials in the stream that could be easily removed, recycled, or reused with minimal effort to show the greatest initial benefit with least cost. The second step was to identify where a particular commodity could be most easily intercepted. The survey was conducted at Eagle Base in Bosnia on three randomly selected days in June 2003. The entire waste stream on those three days was separated into 14 different waste categories. Daily totals for each component were averaged; monthly and yearly amounts were estimated. The yearly estimate also contains the estimated increase in all materials due to the transfer of authority function that occurs twice a year. During these functions, the camps have increased populations for up to one month. A qualitative survey was conducted in Kosovo aimed at finding the sources of the various components that feed into the solid waste stream. Based on these examinations, the waste stream at Kosovo is nearly the same as in Bosnia.
The analysis showed that nearly 90 percent of some commodities were generated and picked up from typically three or four locations. For example, cardboard and wood are concentrated at the Army, Air Force Exchange Service (AAFES), Kellogg, Brown and Root Services (KBRS), and the Supply Support Activity (SSA). Food waste was concentrated at the Dining Facility (DFAC) and AAFES retail fast food outlets; however, commodities such as aluminum cans were slightly concentrated at the DFAC but found throughout the waste stream.
The results indicated that 75 percent of the solid waste burned in Bosnia was scrap wood derived from shipping dunnage and pallets. Twenty percent of the garbage was empty water bottles, and undoubtedly a significant contributor to the noxious fumes. Thus, plastic water bottle reduction became a high value target. The study indicates there are many components that can be recycled, removed, or reused. In September 2003, a plastics recycling vendor was found and as of July 2004, over 85,000 kg of plastic bottles have been recycled. Once the plastic bottles came out of the waste stream, wood, and cardboard were removed for reuse and recycling because their heat energy is no longer required. To date, over 38,000 kg of cardboard has been recycled and 30,000 kg of wood a month is being recycled. The other organics identified in the waste stream will soon be removed as well when the composting operation gets underway this summer.
The waste stream survey results show that the Bosnian base population (including both military and civilian personnel) produces just over 500 kg/year/person of solid waste (0.55 tons/ year/person). When figuring in all the wood that is burned, the figure jumps to 2.5 tons/ year/ person, which is about twice the national average cited in the BioCycle “State of Garbage In America” report in January 2004. The total amount of burned garbage will decline dramatically next year when the full impact of the recycling and composting programs are realized.
BIOREMEDIATION AND BIOSOLIDS MANAGEMENT
Another component of the solid waste strategy was finding a process to bioremediate the 2,000 cubic meters of PCS stockpiled on Camp Bondsteel. The soils had been there for up to two years and had grasses and early plant colonizers growing on the piles. This was a good sign that some naturally occurring bioremediation was taking place. The bioremediation of petroleum products is an aerobic process and the addition of a nitrogen source provides the nutrients that the bacteria need. A healthy microbial community expedites the breakdown process of the petroleum. With a thousand boxes of sewage sludge on hand, the choice of nitrogen source was simple. Mixing the two waste streams seemed to be logical because the sludge is a good source of N, P, and K and trace nutrients. A good bulking agent mixed in would keep the process aerobic. The remediated soil could be used in many environmental projects already identified on post.
At CBS, sewage is treated in a sequencing batch reactor (SBR). The resulting biosolids – at one to three percent solids – are concentrated in a filter press to approximately 3 cubic meters (m3)/day of dewatered, 20 percent sewage cake. The pilot project, which ran from June to December 2003, was conducted to determine the best way to combine the two waste products to promote the bacterial bioremediation of the PCS. Two flat land farming plots (15-feet wide by 65-feet long by 13 to 15-inches high), and two windrow piles (15-feet wide by 65- feet long and about 6 feet high), were established. The piles were made by layering 2- to 4-inches of PCS on the bottom, followed by 3 to 4-inches of sludge, then 6 to 8-inches of straw and topped by 6 to 8-inches of PCS. The windrow pile was set up with the same layering methodology. The piles were mixed initially with a track hoe, then mixed about every day for the first two weeks. Temperature and CO2 content were measured daily in the windrow piles. Longer turning periods were used for subsequent weeks depending on weather and temperature. The moisture of all plots was kept at about 45 to 55 percent.
The results of the Total Petroleum Hydrocarbon (TPH) tests are given in Table 1. Petroleum concentration in the land farming flat plots declined below our 300 ppm contamination limit. That material can be used anywhere on Post with no restrictions. The windrow piles did not do as well in removing the petroleum. We interpret the data as reflecting a less than optimal environment for the petroleum metabolizing bacteria for two reasons. First, the high temperatures reached in the two windrow piles undoubtedly inhibited the mesophilic petroleum-consuming bacteria. Second, the turning method did not achieve the maximum mixing of the components, and did not provide the best aerobic environment for the bacteria.
Taking these lessons learned into account, we designed a larger scale PCS bioremediation plot. This plot was partially constructed before winter and wet conditions precluded further construction. Currently there are three acres of PCS being bioremediated.
The bioremediation program will save in excess of $700,000 in disposal costs for the two waste products. We now have a nutrient rich soil for use as a soil conditioner or fill on erosion projects. The soils will continue the bioremediation process, dropping the concentration of petroleum products to even lower levels. The number of bacteria that are of concern to human health also will drop. All the sludge falls well within a Class B material classification for E.coli.
RESOURCE MANAGEMENT AND RECOVERY
The Balkans solid waste management strategy is maturing from a primitive program based on initial entry conditions into one based on resource management and recovery. This has been possible due to the growing stability within the region, which is opening up markets for the recyclable and reusable materials. With the solid waste survey results, we were able to approach vendors with quantifiable data on the amount of product that would be available. We also knew how to go about setting up programs to get certain products concentrated on post for ease of collection and which products we may need to remove or reduce from the supply channels to make the waste management process more effective. Removing plastic water bottles was our first priority, which involved replacing the old distribution system, conducting an information campaign, and implementing recycling programs with available vendors. These programs have been extremely successful.
The bioremediation of PCS with sewage sludge using the land farming technique was another great success. The windrow technique was not as effective and is not recommended as a method for bioremediation of PCS. The drawback to the windrow system is keeping the pile aerated and the temperature in the mesophilic range. The density of the PCS hinders effective aeration, requiring considerable bulking agent and/ or constant turning. A track hoe is not the best piece of equipment for turning and aerating the land farming plots or the windrows. For small land farming plots, a rotary tiller would be best. For larger plots, a tractor-pulled set of small discs or small tines are recommended. Despite all the learning trials, the land farming remediation process reduced the TPH concentration to less than 300 ppm in about 90 days. The costs for the remediation will be approximately $25/m3.
The current programs outlined in this report are the latest efforts by DCSENG to further environmental stewardship in the ongoing Balkan contingency operations. The program successes stem from innovative approaches to solving problems and dogged persistence by the environmental managers at all levels. The recycling and bioremediation processes explored in this study are applicable to other military operations and the civilian community. We are aggressively expanding our knowledge into other ways to save the Army’s (and the nation’s) resources while providing leadership within the exciting field of environmental stewardship.
The authors are environmental officers with the U.S. Engineer Support Operations in the Balkans. In an email communication sent by Major James Lee in late June, 2004, he writes: “We just started full-scale composting operations at Camp Bondsteel this month. Currently, we are composting stockpiled sewage sludge cake in outdoor windrows. Next month, we will begin a small three-month technology evaluation project using a mobile aerated static heap process that uses a Gore-Tex membrane cover. We will be evaluating the cost and performance of these two approaches at the end of the summer. We shall plan to report our findings in a future issue of BioCycle.”
October 22, 2004 | General
The Balkans — Bosnia Mission Includes Waste Management And Bioremediation
BioCycle October 2004, Vol. 45, No. 10, p. 59