20242064_A1_Attachment A.pdf

ATTACHMENT A: 100% ELASTOMERIC POLYURETHANE COATING (DIGESTER #1)

4.01 ELASTOMERIC LINING SYSTEM FOR CONCRETE

A. The purpose of these specifications is to provide general guidelines regarding installation of a spray applied elastomeric polyurethane lining system for concrete surfaces. Unless indicated otherwise, application to any other substrate is not intended. These specifications principally cover the following system:

B. Vertical & Horizontal applications

Coat No.

Materials Dry Film Thickness

CARBOGUARD 510 Resurfacer As required

1 HYDROPLATE 1080 Epoxy Primer 5-8 Mils

2 REACTAMINE 760HB Elastomeric Polyurethane Coating Basecoat

100 – 150 Mils

Total System 105 – 158 Mils

4.02 SURFACE PREPARATION

A. Inspection shall verify that surfaces are prepared per coating manufacturer’s recommendations before proceeding with application of coating material.

B. Protection of Surfaces Not To Be Coated.

1. During surface preparation and coatings application, all nearby equipment, vehicles, structures, etc. shall be protected from blasting grit, dust and over spray, dropped or spilled materials.

2. Surfaces adjacent to a proposed leading edge of coating application shall be taped-off or otherwise protected.

C. Rigging and Scaffolding

1. Rigging and/or scaffolding, if required, shall be set up to permit ease of operation of surface preparation and application equipment and shall provide safe and clear access to all surfaces to be coated.

D. Decontamination

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1. Before abrasive cleaning, all oil, grease, dirt, loose matter and other contaminants shall be removed by high pressure water blasting, steam cleaning, or any other acceptable method, to satisfy ASTM D-4258 “Surface Cleaning Concrete for Coating”.

2. Environmentally acceptable biodegradable detergents may be used;

however, they shall be completely rinsed off with plenty of fresh, clean water.

E. Abrasive Cleaning

1. Concrete shall be abrasive blast cleaned to satisfy ASTM D4259 “Abrading Concrete”, producing a surface with a roughened texture resembling coarse sandpaper. Concrete shall be free of crusts, soft or weak matter, loose aggregate, and all other contaminants.

2. Sharp edges shall be rounded or trimmed by chipping, wire brushing, or any other acceptable method.

3. At expansion joints, if any, filler compound shall be roughly flush with, or lower than, concrete surface.

4. Wet abrasive blasting shall be allowed provided that water produced does not hinder application of materials. Water blasting alone shall not be allowed, except for decontamination.

5. Acid etching shall not be acceptable.

F. Removal of Existing Coatings

1. If present, existing coatings shall be removed by abrasive cleaning or any other acceptable method.

2. Only small sections of existing coatings that are very firmly adhered and greatly resist removal may remain, however, these sections shall be thoroughly abraded to provide a roughened surface.

G. Substrate Moisture

1. If present, all leaks and infiltrations shall be repaired and eliminated as directed by Owner. Concrete surfaces shall be completely dry prior to coating application.

2. If the concrete surfaces are not completely dry, HYDROPLATE 1080 Primer must be used. Concrete may be damp to the touch, but shall be free of condensation and visible moisture, prior to application of HYDROPLATE 1080 moisture-tolerant epoxy primer.

H. Final Coating

1. All surfaces to be coated shall be free of dust, moisture, and condensation.

2. Nearby surfaces shall be cleaned to prevent wind-blown contamination of substrate or freshly applied coatings.

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4.03 RESURFACING

A. Materials and Applications

1. Depending on coating manufacturer’s specific surface preparation requirements for repair or resurfacing of concrete, Contractor may select and use any or all of the products described below, or pre-approved equals.

2. Resurfacing products shall be mixed, applied, allowed to cure, and treated per their manufacturer’s recommendations, before they are coated.

3. CARBOGUARD 510, as manufactured by Carboline Company of St.

Louis, MO, is a water-based epoxy binder for Portland Cement and sand, applied up to 6” (15 cm) thick as a topping over deteriorated or damaged concrete.

4. It is recommended to use Hydroplate 1080 Epoxy Primer over the Carboguard 510.

4.04 HYDROPLATE 1080 EPOXY PRIMER

A. Material

1. Hydroplate 1080, as manufactured by Carboline Company of St. Louis, MO, is a phenalkamine epoxy primer used as a primer to concrete surfaces. It is a two component system with 80% solids by volume.

B. Handling and Mixing

1. Part A and B components shall be delivered to jobsite in their original unopened containers with labels intact. Containers shall be stored indoors, off the floor, in cool and dry conditions, and shall be protected against excessive moisture, heat and cold, in accordance with manufacturer’s recommendations.

2. Components shall be thoroughly agitated in their original separate containers for 5 minutes to produce complete suspension, then measured to obtain an exact 1A:4B volume ratio, and poured into a dry, clean separate container.

3. Components shall be blended together by agitating for an additional 5 minutes, keeping mixing blade submerged to minimize whipping of air into material, until a uniform mix is achieved. Sides and bottom of container shall be scraped occasionally to ensure uniformity.

C. Primer Application

1. Hydroplate 1080 shall be maintained between 50 °F and 90 °F (10 °C to 32 °C).

2. Ambient temperatures shall be above 20 °F (-7 °C).

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3. Substrate temperatures shall be above 20 °F (-7 °C), and at least 5 °F (3 °C) above dew point and rising. Relative humidity shall not exceed 85%. Suspend application if conditions are not within recommended parameters when snowing, raining, or foggy, or when precipitation is imminent.

4. Hydroplate 1080 can be recoated in about 2 hours at 75 °F. Maximum recoat interval shall not exceed 24 hours at 75 °F.

5. Primer shall be applied at specified film thickness in a single application, using conventional airless spray equipment. Application by brush or roller shall be permitted if spray-application is not practical.

6. Mixed primer that exceeds its pot-life shall not be used and shall be properly discarded.

7. Applied primer shall be protected from contamination by dust, moisture, condensation, etc.

D. Recoat Time

1. Primer shall be top coated with REACTAMINE 760HB after Hydroplate 1080 is set and cured for 2 hours at 75 °F, but within the 24-hour maximum re-coat window at 75 °F.

4.05 REACTAMINE 760HB COATING

A. Material

1. REACTAMINE 760HB, manufacturer and supplied by Carboline Company of St. Louis, MO, is an ASTM D-16 Type V, chemical cure, 100% solids, elastomertic, aromatic polyurethane with no sand fillers or extenders added. It shall be classified in accordance with ANSI/NSF Standard 61 for direct contact with potable water.

2. The coating shall be a two-component system in a 2 parts resin (Part A) to 1 part catalyst (Part B) volume ration (2A:1B), capable of being spray-applied at specified film thickness in a single application. It shall produce a monolithic, flexible membrane.

B. Handling and Mixing

1. Part A and B components shall be delivered to job site in their original unopened steel drums with labels intact. Drums shall be stored indoors, off the floor, in cool and dry conditions, protected against excessive moisture, heat, or cold, in accordance with manufacturer’s recommendations.

2. Part A shall be thoroughly mixed with a drum mounted air-driven agitator for 30 minutes immediately before each use.

3. Agitation of Part B is not be required, unless color tint is used, in which case tint shall be added directly to the drum while agitating, then used immediately. For potable water applications, color tint shall not be added.

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C. Application

1. Coating shall be spray applied by qualified technicians, using plural-component, high-pressure, airless spray equipment, approved by the Supplier, that automatically proportions the Part A and B components, blends them via in-line static mixers, and sprays the mixed coating material at a fluid pressure of 2,500 psi.

2. Coating materials shall be maintained between 80° and 90 °F (27° to 32 °C). Ambient temperatures shall be between 40 ° and 120 °F (4° to 49 °C), and substrate temperatures shall be between 40° and 140 °F (4° to 60 °C) and at least 5 °F (3 °C) above dew point and rising.

3. Relative humidity shall not exceed 95%.

4. Suspend application if conditions are not within above parameters, when snowing, raining or foggy, or when precipitation is imminent.

5. Each coat shall be applied at specified film thickness in a single application, which may consist of several increments, accomplished by one or more passes of the spray gun, all applied within recommended recent times to a specific area. High profile areas shall be coated using 4-way passes of the spray gun to ensure complete coverage. If necessary, film thickness may be increased as needed, until a holiday-free membrane is achieved.

6. To minimize the creation of pinholes due to outgassing of air from porous concrete surfaces, coating shall be applied during a cooling trend in the concrete’s surface temperature, in multiple increments of 20 to 30 mils (0.5 to 0.75 mm) per spray pass with little to no time needed between passes.

D. Installation of a Bonded Geomembrane (Optional)

1. This option may be utilized on suitable vertical and horizontal surfaces, when a reinforced system is desired, or as an alternative to resurfacing before installing the Reactamine 760HB system.

2. Fabric Material

a. Non-woven, 100% polypropylene fabric, needle punched, and

“heat-set” on one side, as manufactured by Carthage Mills of Cincinnati, OH, or pre-approved equal.

b. Fabric shall weigh 8 to 10 oz./yd.² (250 to 313 g/m²), or as appropriate for the intended use.

3. Embedding the Fabric

a. Pre-cut fabric panels shall be firmly pressed and embedded, ”heat-set” side facing out, into the REACTAMINE 760HB basecoat while it remains in a semi-liquid state.

b. Fabric shall be evenly pressed with a non-stick roller, squeegee or trowel to ensure that it is adhered flat against the basecoat in all locations. DO NOT SATURATE THE FABRIC.

c. Over irregular surfaces, fabric shall be pressed by hand (use suitable protective gloves) to maximize contact with basecoat.

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d. Adjoining panels shall be overlapped by 2 inches (5 cm) and bonded together with REACTAMINE 760HB, spray-applied between the overlapping fabric

4. Anchoring the Fabric

a. Embedded fabric panels may, when conditions require, be mechanically fastened to the concrete substrate using ¼” diameter x 2” long suitable stainless steel anchor bolts with 1½“diameter washers, installed at 36” centers, or as appropriate for intended use.

5. Coating the Fabric

a. REACTAMINE 760HB topcoat shall be spray-applied directly to the exposed “heat-set” side of the embedded fabric to produce complete coverage in all locations.

b. Exposed fabric fibers or edges, or any other discontinuities shall not be acceptable.

c. If necessary, applied film thickness shall be increased, as needed (beyond specified thickness), to produce complete coverage and sealing of the geotextile fabric.

E. Recoating / Transitions

1. Fresh coating may be sprayed over previously applied coating as long as undercoat remains wet or tacky to the touch or has not exceeded 4 hours at 70°F (21°C) since application. Higher temperatures shorten the recoat window, and colder temperatures extend the recoat window.

2. If recoat time is exceeded, undercoat shall be brush blasted to remove gloss, then vacuumed or solvent-wiped to dust-free condition, allowing all solvent to dry, before application of fresh coating.

3. For transitions between coating sections applied on different days, a minimum 12 inches (30 cm) of the undercoat shall be brush blasted and prepared as described above, and fresh coating shall be feathered in at least 6 inches (15 cm). Avoid application to glossy surfaces, making sure there is plain evidence of brush blast beyond leading edge of fresh coating. Coating applied to improperly prepared surfaces shall be removed immediately.

F. Service

1. The coating or lining system may be placed in service upon satisfactory inspection by Contractors Quality Assurance and third-party coating inspector.

2. Minimum cure time for immersion is 1 hour at 85°F (29°C), 2 hours at 73°F (22°C), or 4 hours at 60°F (16°C.

4.06 TREATMENT OF LEADING EDGES

A. Placement of Saw-Cuts

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1. During surface preparation, a saw-cut shall be made along each proposed leading edge of coating application.

2. Saw-cuts shall be ½ to 1-in. deep (1.25 to 2.5 cm) x 1/8 to ¼-in. wide (0.3 to 0.6 cm). Sharp edges shall be rounded or trimmed, and saw-cut cavity shall be vacuumed to a dry, dust-free condition.

3. Adjacent surfaces not to be coated shall be protected from overspray by taping-off in a neat manner.

B. Application

1. A liberal amount of coating material shall be spray-applied to saw-cut area, then pressed with trowel or putty knife into the saw-cut cavity and smoothed level, mechanically anchoring the leading edge to the substrate. After coating sets up, it shall be razor-cut to remove the protective tape, leaving a straight, neat, leading edge.

4.07 TREATMENT OF PROTRUSIONS

A. Surface Preparation

1. Surfaces shall be prepared to satisfy coating manufacturer’s recommendations for applicable substrate. Surface preparation shall extend beyond proposed leading edge of coating application. Surfaces shall be dry and dust free. before coating. Adjacent surfaces not to be coated shall be protected from overspray by taping-off in a neat manner.

B. Application

1. Protrusion surfaces shall be coated concurrently with adjacent concrete surfaces, to satisfy manufacturers recommendations for applicable substrate. After coating sets up, it shall be razor-cut to remove protective tape, leaving a straight, neat leading edge.

4.08 TREATMENT OF EXPANSION JOINTS

A. Where the Geotextile System is used on 100% of the surface, no special treatment of the expansion joints is required.

4.09 INSPECTION

A. The Contractor shall enlist the aid of various tests and perform those tests to verify the integrity of the applied lining to their, and the Owner’s satisfaction.

The Owner shall be permitted full access at all times to observe and be satisfied the specifications are being followed. The Owner will be given sufficient notice to be present, if desired, when the following points are reached.

1. Completion of surface preparation

2. During primer/filler application

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3. Prior to REACTAMINE 760HB

4. During wet and dry film testing

5. During pinhole detection testing

6. During any repairs of the coating system

B. Surface Preparation

1. Contractor shall verify that surfaces are prepared per coating manufacturer’s recommendations. Inspection will be performed by Contractor’s Quality Assurance and a qualified third-party coating inspector.

C. Ambient Conditions

1. Ambient conditions shall be monitored and maintained within recommended parameters. Dew points shall be monitored per ASTM E- 337 “Measuring Humidity with Psychrometer”, to determine wet and dry-bulb temperatures. Thermometers shall be used to measure temperatures of coating materials, and surfaces to be coated.

D. Primer Application

1. Inspection shall verify that primer is mixed at proper volume ratio and applied with no evidence of streaks or uneven coloring. Film thickness shall be verified by logging volumes of material applied to pre-measured areas.

2. Inspection shall verify that applied primer is protected from contamination, and top coated with REACTAMINE 760HB within recommended recoat time.

E. Coating Application

1. Inspection shall verify that coating is applied using spray-equipment approved by coatings manufacturer monitoring its operation to verify that materials are applied with no evidence of streaks or uneven coloring.

2. Film thickness shall be verified by logging volumes of material applied to pre-measured areas, using a machine mounted, mechanical “stroke-counter” that records number of pump strokes applied.

3. Inspection shall verify that any recoating is accomplished within recommended recoat times. Inspection shall verify that no fresh material is applied to glossy or improperly prepared surfaces, and that any material so applied is completely removed. The coating shall be visually inspected for blisters, poor adhesion, or improper cure. Deficiencies shall be marked and repaired per coating manufacturer’s recommendations.

F. Holiday Detection

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1. The coating shall be inspected per ASTM D-4787 “Continuity Verification of Liquid or Sheet Linings Applied to Concrete Substrates” or “NACE RP 0188”, using high-voltage spark testing equipment with variable settings. Test voltage shall be set at an initial 100 volts per mil (4,000 volts per mm) of specified film thickness, then increased as needed to compensate for relative conductivity of the concrete substrate by spark testing an induced holiday at furthest extension of test probe from grounding location. Once test voltage is determined, it shall be used throughout that area, then re-determined again every time a new ground is made. Detected holidays shall be marked and repaired per coating manufacturer’s recommendations.

2. For bonded geomembranes, test voltage shall be set at an initial 100 volts per mil (4,000 volts per mm) of total system thickness – including the geotextile fabric.

G. Requited Contractor Testing Equipment

1. The following inspection equipment, or pre-approved equal, shall be utilized by the Contractor for performing quality control testing:

a. Sling psychrometer

b. Psychrometric charts for determining relative humidity and dew point

c. Surface temperature thermometer

d. Ambient temperature thermometer

e. High range wet and dry film thickness gauges

f. Micrometer

g. Durometer

h. Sample cans

i. Inspection glass (30 power minimum)

j. High voltage pinhole detector

4.10 PATCHING AND REPAIRS

A. Surface Preparation

1. Repair area shall be decontaminated, and deficient sections shall be removed until properly applied, firmly adhered coating materials are reached. Exposed surfaces shall be treated to satisfy applicable requirements. Coating material surrounding repair area shall be abraded to remove gloss, then solvent-wiped to dust-free condition and allowed to dry before application of repair materials. The extent of abraded area shall depend on whether repair materials are spray or hand-applied, but in either case, no repair material shall be applied beyond abraded areas.

B. Material and Application

1. A maximum 12 fl. oz. (350 ml) of REACTAMINE 760HB coating material shall be hand-mixed in a 2A:1B volume ratio, then quickly and evenly applied by brush or putty knife, covering the repair area. Repair

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4.11 CONTROLLED ENVIRONMENT

A. Dehumidification

1. To prevent delays or unsatisfactory results in coatings application due to excessive ambient moisture or condensation, Applicator shall be equipped and prepared to provide a suitable dehumidification system, to produce an environment conducive to application within recommended parameters.

2. Heating alone shall not substitute for dehumidification.

B. Heating

1. To prevent delays or unsatisfactory results in application or cure of the coatings due to excessive cold, Contractor shall be equipped and prepared to provide a suitable explosion-proof heating system, to elevate substrate temperatures within recommended parameters. When heating is employed, all precautions shall be taken to prevent formation of dew or condensation on surfaces to be coated.

END OF ATTACHMENT A

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