2012-054 RES AWARDING CONTRACT FOR REHABILITATION OF EAST ELEVATED STORAGE TANK TO CLASSIC PROTECTIVE COATINGS INC

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SSPC-Guide 6 October 1, 2004 5.4.3.2 Type H2 - Visual Verification: Negative pressure must be employed as verified through the concave nature of the wall, ceiling, or floor materials while taking into account wind effects. Smoke or other visible means inside or outside the containment can be used to observe air flow patterns. 5.4.3.3 Type H3 - Not Required: Specified degree of negative pressure not required. 5.4.5 Exhaust Air Flow/Dust Collection 5.4.5.1 TypeJ1-Air Filtration Required: Forced exhaust air flow into dust collectors (wet or dry) or baghouses sized appropriately for the type and size of particulate matter and for the volume and velocity of air moved througn the contain- ment. SSPC Guide 16 provides information on the selection of dust collectors. 5.4.4 Air Movement Inside Containment: Air movement is utilized inside containment for several reasons: • to reduce the exposure of workers to airborne dust (e.g., in 29 CFR 1926.62, OSHA stipulates that en- gineering controls must be instituted to the extent feasible to control worker exposure to lead dust) • to improve visibility • to remove dust laden air • to aid in preventing contaminants from escaping into the environment (e.g., in 40 CFR 260-268 EPA stipulates that no hazardous debris is permitted to be deposited on the ground, but no specific criteria have been established to achieve these goals) 5.4.4.1 Type li - Minimum Air Movement is Specified: Achieving air movement through the containment requires the use of inechanicalventilation (see Note 7.1). Air movement may be specified by several methods, such as the following: • establishing a minimum velocity of air (fpm) in cross- draft or down draft (see Note 7.2) • establishing a minimumvolumeof air(cfm) toventilate a given volume of containment The selection of inethods and criteria for specifying or producing air movement should be based on an analysis of project-specific conditions, including the blasting pressure, number and size of blast nozzles, type, size and friability of abrasive, flow rate of abrasive, the lead or toxic metal content, thickness and age of the paint being removed, the type and size of structure being prepared, and the configuration of the containment system being installed. While there are generally accepted criteria for specifying air movement, air velocity past the worker is often a primary consideration when designing ventilation systems, because of worker protection issues. 5.4.4.2 Type 12 - Minimum Air Movement is Not Speci- fied: Under this approach, the specifier does not establish any criteria for minimum air movement in containment. Note that when removing lead-containing paints, it may still be necessary to utilize feasible engineering controls to reduce airborne lead exposure in accordance with the provisions of 29 CFR 1926.62 and to prevent the escape of airborne lead particulates from the containment. 5.4.5.2 Type J2 - Air Filtration Not Required: Natural exhaust air flow is employed without the use of forced air or dust filtration. Little control overthe debris being emitted into the environment is possible when using dust-producing methods of preparation such as abrasive blasting. 5.5 METHODS FOR ASSESSING GIUANTITY OF EMISSIONS: Surface preparation and paint removal opera- tions produce dust and debris which may be emitted into the environment. Methods for quantifying the amount of dust and debris escaping the work area are described below. MethodsA and G provide immediate feedback on the emissions created. Methods B, C, and D require days to receive results. Methods E and F provide results upon project completion. Users should contact the appropriate state and local authorities to ascertain which of the methods are accepted for monitoring emissions, and to establish the appropriate acceptance criteria. Guidance on methods of monitoring is found in SSPC-TU 7. NOTE: Testing for PM-10 or monitoring ofvisible emissions may be of limited applicability or relevance to a hazardous paint removal project. Monitoring for the toxic metal (e.g., lead as in 5.5.4) may provide more useful and meaningful data. 5.5.1 Method A-Visible Emissions: Observations of vis- ible emissions from the work area provide immediate feedback on the performance of the containment system. Two methods can be used: 5.5.1.1 General Surveillance: Visible emissions are permitted at given frequencies or durations provided they do not extend beyond an established boundary line (e.g., property line). Possible frequencies include: • Level 0 Emissions - No visible emissions. NOTE: This level is typically not achievable during abrasive blasting. Leveli Emissions-Randomemissionsofacumulative duration of no more than 1°/a of the work day (e.g., five minutes in an eight hour work day). Leve12 Emissions- Random emissions of acumulative duration of no more than 5% of the work day (e.g., 24 minutes in an eight hour work day). Level 3 Emissions - Random emissions of a cumula- tive duration of no more than 10% of the work day (e.g., 48 minutes in an eight hour work day). 9-9