12-2 Hazard Analysis

Principal unique hazards associated with landfarming include:

a. Physical Hazards

(1) Description: During soil excavation and landfarm construction, workers may be seriously injured or killed by heavy equipment such as front-end loaders and scrapers. Landfarm construction may include the preparation of berms which may be steep and become slippery in wet or rainy conditions.

Control: Heavy equipment should be equipped with a backup alarm that alerts workers. When approaching operating equipment, the approach should be made from the front and within view of the operator, preferably making eye contact. Workers should refrain from walking on or near the berms, especially during or after periods of heavy rainfall. CONTROL POINT: Construction, Operations, Maintenance

(2) Description: Installation of landfarm liners/covers in high winds may pose hazards to workers as blowing liners may trip or knock down workers holding or standing on or beside unsecured liners.

Control: Controls include installing liners on calm days, or placing soil or sand bags onto the liner to anchor it. The installer should determine the anchoring needs at the time of installation, and should ensure that the specifications for anchoring are met or exceeded. CONTROL POINT: Construction, Maintenance

(3) Description: Installation of landfarm liners/covers can pose an increased slip hazard, particularly when wet. Plastic and wet clay liners can be very slippery and, when placed on the slopes or used for footing, can be a significant slip hazard.

Control: Controls for this hazard may include using rope ladders or stairs for ascending/descending lined slopes, selecting appropriate shoe soles for maximum traction, erecting barriers or warnings around excessively wet areas of liner, laying high traction walkways over the liners, carrying light loads, or using more workers to carry larger single loads. CONTROL POINT: Design, Construction, Operations, Maintenance

(4) Description: Synthetic liners are made in varying thicknesses and rigidities. Some liner edges are sharp and stiff after cutting to shape, and can inflict cuts to the skin and eyes, and abrasions.

Control: Controls include long-sleeve shirts, full-length pants, and appropriate work gloves (e.g. leather) for better grip and protection. Safety glasses should also be worn to help prevent cuts to the eyes during liner installation. CONTROL POINT: Construction, Maintenance

(5) Description: Heat-related illnesses may be more prevalent during installation of synthetic liners. Most synthetic liner materials are dark or black to enhance ultraviolet (UV) resistance, and thus absorb radiant energy and emit considerable heat. The polished surfaces of liner materials can also reflect considerable angled radiant energy, enhancing the energy absorbed by the worker even when under a canopy or wearing a hat. Heat stress, including heat exhaustion and heat stroke, may occur to workers during operations and conditions that contribute to the heat load. Hot and humid conditions combined with operations, such as liner welding or other heat-producing activity, may further increase the potential for heat-related illnesses.

Control: Control may involve re-emphasis of mechanisms for avoiding heat-related illnesses including vigorous worker training in the signs and symptoms of heat stress, use of the "Buddy System", ready access to water, frequent mandatory breaks, and provision of canopies or other shaded break areas. CONTROL POINT: Design, Construction, Operations, Maintenance

(6) Description: Manual lifting and moving of large rolls of folded/rolled liner material or weighted materials used for anchoring may expose workers to lower back and shoulder stress.

Control: Mechanical lifting equipment, such as cranes, backhoes, and spreaders should be used to lift and move liner material to help avoid ergonomic hazards to workers. CONTROL POINT: Construction, Operations, Maintenance

(7) Description: Burn hazards to the skin may exist with exposure to different types of operating equipment including a liner extrusion welder and generators.

Control: All personnel using or exposed to hot operating equipment during the installation of the landfarm liners should be informed as to the hazards posed by the equipment. All exposed, heated surfaces should be guarded to prevent accidental contact. Procedures for the safe operation, repair, and maintenance of this equipment should be prepared and should include a testing procedure for determining safe temperature. The use of insulated gloves with gauntlets, coveralls, and face protection may be warranted. CONTROL POINT: Construction, Maintenance

(8) Description: Landfarm units may require periodic aeration by mechanically turning over soils with heavy equipment such as mixing equipment, rototillers, plows, discs and tillers. The mixing equipment may be equipped with a rotary device which lifts and turns soil. Other devices, such as a "scarab"-type device may throw debris during the turning process. Pre-screening or sizing equipment, such as grinders, shakers, and screeners, may pose machine guarding hazards with unguarded equipment. Appendages or loose clothing may become entangled in pulleys, drive shafts, and other moving equipment.

Control: Workers should keep clear of operating equipment and approach only when within view of the operator. All moving or rotating equipment must be guarded to prevent accidental contact. Workers should only operate the system with the machine guards in place. CONTROL POINT: Construction, Operations, Maintenance

(9) Description: Workers may be exposed to puncture and cut hazards to feet and hands from rough or jagged waste materials during landfarming operations.

Control: Workers should wear safety boots with steel shanks to prevent cuts to the bottom of the foot. Workers should minimize manual handling of waste material, and wear cut-resistant gloves if contact with waste materials is necessary. CONTROL POINT: Construction, Operations, Maintenance

(10) Description: Trip hazards may exist with hoses and piping systems used for irrigation of the landfarm.

Control: Workers should exercise caution when walking over hoses and pipes. In heavily traveled areas, extra lighting may be needed to ensure walkways are adequately illuminated. CONTROL POINT: Design, Maintenance

(11) Description: Depending on soil types, exposure to respirable quartz may be a hazard. Consult geologists to confirm the presence of a respirable quartz hazard (e.g. to determine if soil types are likely to be rich in respirable quartz). As an aid in determining respirable quartz exposure potential, sample and analyze site soils for fines content by ASTM D422, followed by analysis of the fines by X-Ray Diffraction to determine fine material quartz content.

Control: Worker exposure to dust rich in respirable quartz may be minimized by periodically wetting the soil with water or amended water or by the use of respiratory protection, such as an air-purifying respirator equipped with a HEPA(P100) filter/cartridge. CONTROL POINT: Construction, Operations

(12) Description: Workers may be exposed to electrocution hazards when working around electrical utilities such as overhead power lines.

Control: The location of overhead power lines, either existing or proposed, should be noted in the pre-design phase. All lifting equipment, such as cranes, forklifts and drilling rigs should remain at least 10 feet from the power line. (Occupational Safety and Health Administration (OSHA) regulation 29 CFR 1926.550 and EM 385-1-1, Section 11.E.) CONTROL POINT: Design, Construction, Operations

(13) Description: Equipment used to move soil and liner materials on steep slopes may roll over, seriously injuring or killing the operator.

Control: The angle of the slope should be designed to minimize the potential for roll-over. The construction contractor must maintain safe operating conditions for equipment during construction. Equipment should be equipped with roll-over protective devices (ROPS), and should not be operated on excessively steep slopes or unstable ground. CONTROL POINT: Design, Construction, Operations

(14) Description: During the implementation of field activities, equipment and workers may come in close proximity to traffic. Equipment may also need to cross public roads. The general public may be exposed to traffic hazards, and to the potential for accidents during loading and transporting soil.

Control: Where equipment is to cross roads, warning signs should be used according to the criteria of the Department of Transportation Manual on Uniform Traffic Devices for Streets and Highways. A traffic management plan should be developed before remediation activities commence to help prevent accidents involving site equipment. EM 385-1-1, Section 21.I.10 provides plan details. CONTROL POINT: Design, Construction, Operations

b. Chemical Hazards

(1) Description: The heating or cementing of the cover/liner materials may generate vapors, either from the cement applied or from thermal decomposition, and/or outgassing of the liner material components such as plasticizers (e.g. phthalate esters, adipate esters), or from the solvents contained in the cementing agent (e.g. methyl ethyl ketone, methylene chloride). A vapor inhalation hazard may exist to workers during liner installation. A dermal hazard may also exist from skin contact with the cementing chemicals, and/or waste materials generated during installation.

Control: During installation, workers may need to ventilate the area, or use appropriate respirators to control exposures. Respirator cartridges (e.g. organic vapor cartridges) should be selected based on consultations with the liner manufacturer(s), and the potential compounds which may be emitted. Use of personal protective equipment (e.g. chemically-resistant gloves such as nitrile for gasoline) may be used to help control dermal exposure. An analysis of the work tasks and potential for chemical exposure should be performed to determine the correct personal protective equipment (PPE) and/or respirator cartridge(s), if needed. The analysis should include obtaining specific chemical hazard information on the liner constituents, and/or constituents used in cementing agents to ensure that PPE specified will be appropriate for each chemical hazard. CONTROL POINT: Construction, Maintenance

(2) Description: Workers may be exposed to contaminants of concern and chemical reagents. The addition of urea or other ammonia-based fertilizers may result in worker exposure to ammonia. Intermediate degradation products, resulting from breakdown of contaminants of concern, may also represent exposure hazards. Exposure may occur via inhalation/ingestion/dermal contact routes of exposure during loading, unloading, preprocessing, tilling, turning, and other landfarming processes where soils are agitated.

Control: During the addition of urea and other nitrogenous fertilizers, workers should use personal protective equipment (e.g. butyl rubber gloves for exposure to nitrogen compounds) to control dermal exposure. An analysis of the work tasks and potential for chemical exposure should be performed to determine the correct PPE and/or respirator cartridge(s), if needed. The analysis should include obtaining specific chemical hazard information to ensure that the PPE specified will be appropriate for the respective chemical hazard. Workers may also use respiratory protection including the use of an air-purifying respirator equipped with HEPA(N100, R100, P100) filters and organic vapor cartridges. CONTROL POINT: Operations

(3) Description: If the land treatment unit facilities are enclosed or tented, workers entering the landfarm may be entering a confined space and require respiratory protection.

Control: The atmosphere within the enclosure of tent should be frequently tested to ensure a safe atmosphere. If the testing indicates atmospheric contaminants or oxygen depletion, a confined-space entry program should be developed and implemented. CONTROL POINT: Design, Operations

(4) Description: Workers may be exposed to burn hazards during handling of acidic or caustic chemicals potentially used for pH control. Some materials used in landfarming may pose explosion hazards if contact is made with other incompatible materials (e.g. ammonium nitrate and fuels). Others may be hygroscopic, which may result in chemical reactions.

Control: Workers should minimize contact with acidic or corrosive chemical materials by using mechanical chemical delivery methods. Where contact is required, workers should wear gloves (e.g. nitrile) and other personal protective equipment that is resistant to the materials handled. Chemical reagents used in landfarming should be segregated to prevent accidental mixing of reactive chemicals, especially ammonium nitrate fertilizers and fuels. CONTROL POINT: Design, Operations

c. Radiological Hazards

Description: NONAPPLICABLE

Control: NONAPPLICABLE

d. Biological Hazards

(1) Description: Landfarm activities may expose workers via inhalation/ingestion/dermal contact exposure routes to pathogenic microbes if the wastes being treated contain pathogenic agents. The hazard may increased during dry and windy periods when microbe-entrained dusts may become airborne from soil agitation, by aerators, or from wind. Exposure may occur during installation of the landfarm liner or during agitation of the waste material. Inhalation of pathogenic microbes may cause allergic reactions or illness.

Control: The amount of airborne dust and consequently the amount of exposure may be controlled by the periodic application of water to the active area. Personal protective equipment, such as rubber gloves, should be used to help prevent dermal exposure to microorganisms, and respiratory protection (e.g. air-purifying respirator with HEPA filter/cartridge) may be used during dusty periods. CONTROL POINT: Construction, Operations

(2) Description: Workers may be exposed to a wide array of biological hazards, including snakes, bees, wasps, ticks, hornets, and rodents, during any phase of remediation. The symptoms of exposure vary from mild irritation to anaphylactic shock and death. Exposure to deer ticks may cause Lyme disease.

Control: Periodic inspections of the site should be performed to identify stinging insect nests and for the presence of snakes. Professional exterminating companies should be consulted for removal. Tick and insect repellents may be used for exposure control. However, workers should check their skin and clothing for ticks periodically throughout the work day. CONTROL POINT: Construction, Operations, Maintenance