24-2 Hazard Analysis

Principal unique hazards associated with incineration include:

a. Physical Hazards

(1) Description: Incinerators may cause elevated noise levels in the work area due to the operation of air blowers, pumps, and the ignition of fuels within the combustion chamber. The noise level may interfere with safe and effective communications.

Control: CEGS 02288 (Remediation of Contaminated Soils and Sludges by Incineration) provides the regulatory requirements which should be followed to address noise. Personal protective equipment (PPE) should include hearing protection. Personal electronic communications devices, such as a dual ear headset with speaker microphone, may be used to overcome ambient noise. Noise-free areas should be established during operations to provide breaks from the noise, which can cause fatigue and inattention. CONTROL POINT: Design, Operations

(2) Description: Incinerators operated with rotary kilns that are not operated properly may cause the solid waste material to vitrify into a large hot mass within the unit. The resulting heat and pressure buildup may exceed design specifications of the unit, potentially causing damage to the unit and possible release of waste materials. Vitrified material may fall on workers entering the unit during maintenance.

Control: Operation of the unit should follow the instructions in CEGS 02288, Remediation of Contaminated Soils and Sludges by Incineration. Section 1.2.2.3 of the standard addresses slagging control requirements. The standard also requires the following plans:

- A Mobilization Plan;

- A Startup Plan describing in detail control system functions and specific procedures proposed to demonstrate each function and for testing the system with uncontaminated materials;

- A Trial Burn Plan listing the proposed operating conditions to be continuously monitored and recorded; and

- A Demobilization Plan.

The unit should be operated within the design parameters and control parameters. Operations should be audited periodically and reviewed for excursions from standards. Controls which prevent entry into the unit until all material has cooled should be incorporated into the design. CONTROL POINT: Design, Operations, Maintenance

(3) Description: Incinerators usually require storage of flammable or combustible fuels (e.g. kerosene, waste fuels). Hazards associated with flammable/combustible fuels include the potential for an on-site spill or release of material. The release may cause worker exposure to the vapors generated or a fire hazard may exist if the material is ignited.

Control: Fuel system installation/storage and testing must comply with the applicable requirements of NFPA 30 (Flammable and Combustible Liquids Code), NFPA 31 (Installation of Oil Burning Equipment); NFPA 54 (National Fuel Gas Code; or NFPA 58 (Standard for the Storage and Handling of Liquefied Petroleum Gases), as appropriate to the type of fuel. CONTROL POINT: Design, Operations, Maintenance

(4) Description: Worker exposure may occur during excavation and transport of waste materials. Dry soils may generate airborne dusts contaminated with toxic materials. During excavation of waste materials with low flash points, soils saturated with flammable or combustible materials may be ignited by sparks generated when the blade of the dozer or crawler contacts rocks or other objects. If the soil is to be crushed to the proper size prior to feeding it into the incinerator, waste materials with high BTU values may be ignited during the crushing/sorting process.

Control: Controls for preventing the generation of airborne dusts include periodic wetting of the soil. Wetting of the soil before and during crushing may help prevent ignition. The soil handling equipment may also be equipped with non-sparking buckets or blades. CONTROL POINT: Operations

(5) Description: Since incinerators operate electrical systems outdoors, workers may be exposed to electrocution hazards.

Control: Verify that the hazardous area classifications, as defined in NFPA 70-500-1 through 500-10, are indicated on the drawings. All controls, wiring, and equipment, including adequate ground-fault protection, should be in conformance with the requirements of EM 385-1-1, Section 11.G and NFPA 70 for the identified hazard areas. CONTROL POINT: Design, Construction, Operations, Maintenance

(6) Description: Workers may be exposed to waste chemicals via the inhalation exposure route if high BTU waste material is fed into the incinerator at a rate that exceeds its design parameter. The heat and pressure generated may over pressure the system, resulting in a release of waste chemical vapors into the work area.

Control: Use experienced operators and supervisors. Audit and apply proper QA/QC to assure work is done as designed. Operate the system within design parameters. CONTROL POINT: Design, Operations

(7) Description: The incineration process can be isolated as one piece of equipment with two or more additional waste processing units attached. Most waste incinerators will include similar equipment used in a thermal desorption unit for handling materials at the inlet and exit of the unit. Accordingly, there may be off-gas conditioning equipment similar to vapor scrubbers or catalytic converters added to incinerators. Each piece of equipment has its own hazards. The basic design requirements for incinerators are regulated by the Environmental Protection Agency (EPA). These design requirements are specified to eliminate releases of contaminants that cause related personnel exposure.

Control: Include hazard control to support all the individual systems included in the system. Design the incineration process according to EPA requirements. Design requirements should meet CEGS 02288: Remediation of Contaminated Soils and Sludges by Incineration. CONTROL POINT: Design

(8) Description: Improperly designed systems can corrode or dissolve to a point of failure and cause damage to the facilities or exposure to workers.

Control: All transfer equipment (conveyors, piping, process units and instruments) in contact with contaminated materials should be fabricated from materials that are chemically-resistant to that chemical. Typical chemical resistance charts can be found through the National Association of Corrosion Engineers (NACE). Where liquids may separate from solid materials or when incinerating liquids, containment drip pans or receivers should be included in the design. Spill and/or leak detection instruments can be installed to monitor for leaks or spills and set off alarms when appropriate. CONTROL POINT: Design, Construction, Maintenance

(9) Description: Workers may be exposed to burn hazards to the skin from hot ash during operation and clean out of the incinerator.

Control: Temperature safety control systems should be included to protect people and equipment. The design of the systems should also consider the handling of materials exiting the system. Safety barriers can be included to isolate critical sections of the equipment. Signs should be posted warning of high temperatures. CONTROL POINT: Design, Operations, Maintenance

(10) Description: Transfer systems such as feed belts, augers, conveyors, etc. expose workers to injury if limbs or clothing are caught in the system.

Control: Transfer systems should be enclosed to the maximum extent possible. Emergency shutoff controls should be installed in multiple locations. Lock-out/tag-out procedures should be rigorously enforced. CONTROL POINT: Design, Operations, Maintenance

(11) Description: Workers may be exposed to infrared radiation hazards associated with working in the vicinity of incinerators. The exposure, depending on the temperature of the equipment, length of exposure, and other variables, may increase the risk of cataracts.

Control: Workers should minimize their exposure to heated equipment surfaces. If prolonged work is required, eye protection using the appropriate shade safety glass may help to control exposure to the eyes. CONTROL POINT: Operations, Maintenance

(12) Description: Depending on soil types, exposure to respirable quartz may be a hazard. Consult geology staff 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 the use of respiratory protection such as an air-purifying respirator equipped with a HEPA(N100, R100, P100) filter/cartridge, and/or by peridically wetting the soil with water or amended water. CONTROL POINT: Operations, Maintenance

b. Chemical Hazards

(1) Description: During maintenance of the incinerator, workers entering the unit for cleaning, inspection, or repair of equipment may be exposed to waste materials or incomplete combustion byproducts, such as chlorine and carbon monoxide.

Control: The controls associated with minimizing exposure to these materials include adherence to confined-space entry protocols which address air testing of the space prior to entry and PPE requirements, such as an air-purifying/air-supplying respirator with organic vapor cartridges and water/chemical impervious gloves. CONTROL POINT: Operations

(2) Description: During operation of the incinerator, workers may be exposed to waste components/toxic materials in the feed or to byproducts of incomplete combustion, such as carbon monoxide, or to airborne toxic materials, including metal acetates, mercury, and chlorine. In addition, toxic byproducts, such as dibenzofurans and dioxins, may also be generated during the process.

Control: Wastes should be classified prior to incineration and only those waste materials compatible with the process should managed in the unit. The design should set limiting parameters on feed characteristics and meet the requirements of CEGS 02288: Remediation of Contaminated Soils and Sludges by Incineration. The design should select the appropriate technology for the known or anticipated wastes to be treated. Appropriate ventilation controls, PPE for workers, and handling procedures should be designated prior to incineration. CONTROL POINT: Design, Operations, Maintenance

c. Radiological Hazards

Description: NONAPPLICABLE

Control: NONAPPLICABLE

d. Biological Hazards

Description: NONAPPLICABLE

Control: NONAPPLICABLE