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The project investigated methods to circumvent problems associated with mercury contamination of aluminum heat exchangers used in ethylene and cryogenic gas plants. Mercury originates from feedstocks and accumulates in piping during cryogenic operation. Damage in the form of amalgamation and liquid metal embrittlement (LME) occurs when the equipment is allowed to warm to ambient during plant shutdown. The report describes the results of experiments designed to develop (1) methods to detect LME by acoustic emission, (2) a chemical means to remove mercury from contaminated equipment, (3) methods to treat the surface of susceptible materials to improve their resistance to mercury attack and (4) to develop test procedures to detect mercury and assess the condition of equipment. Acoustic emission procedures were developed that can detect amalgamation and LME in equipment. A chemical cleaning process was developed which can safely remove mercury from contaminated equipment. A surface treatment process (shot peening and thermal oxidation) was discovered which provides immunity to attack in the presence of mechanical strain. A capacitance test method was developed which can assess the surface condition of equipment exposed to mercury contamination.