Attachment_2_Elephant_Butte__NM_Concrete_Tank_Insp_Rpt_0001.pdf

February 10, 2022

Tina Villegas

Bureau of Reclamation

555 Broadway Blvd. NE, Suite 100

Albuquerque, NM 87102

Re: Elephant Butte Concrete Water Storage Tank Inspection

Ms. Villegas, This tank inspection report was commissioned by the United States Bureau of Reclamation (Bureau) to assess the condition of the interior and exterior of one (1) concrete water storage tank located in Elephant Butte, New

Mexico. On January 12, 2022, D&R Tank’s certified NACE inspector, Noel Vargas, and Dusty Vega conducted an inspection, along with D&R Tank’s subcontractors Industrial Inspection & Consulting and Heerup

Engineering, and found the tank to have the following features:

Volume 300,000 Gallons

Diameter 47 feet

Height 23.5 feet

Purpose Potable Water Supply

Tank Type Concrete with Fiberglass Interior Lining

Roof Self-Supporting Wood

Foundation Type None

Roof Hatch(es) 28.5” x 24”

Shell Manway(s) None

Vent Yes

Ladder(s)/Stairs None

Level Monitoring System Mechanical and Electronic

Inlet(s) One 6” Inlet Pipe (approx. 6” above floor)

Outlet(s) Two 6” Outlet Pipes (approx. 6” above floor)

Drain(s) 2” Pipe

Overflow 6” Pipe Between Shell Wall and Roof

Cathodic Protection N/A

In order to gain entry, D&R Tank subcontracted with Superior Roofing to cut a temporary access point in the roof.

This access point was later closed up. The existing hatch was not suitable for safe entry due to the installation of level control equipment. In general, the tank was found to be in fair and functional condition but is in need of rehabilitation in the very near future. With proper rehabilitation this tank will last several decades to come.

All observations below are compared to current codes, standards, and best industry practice, although it is understood that this tank may have been constructed under older codes and standards. The following summarizes the observed conditions:

Elephant Butte Dam Concrete Tank

P a g e 1 | 6

Roof in poor condition. Roof in very poor condition.

P a g e 2 | 6

Tank Site. Trees growing from tank foundation should be removed.

P a g e 3 | 6

Concrete spalling on side wall of tank. Roof penetration made for tank access.

P a g e 4 | 6

Roof in poor condition. Existing roof hatch with level control equipment.

P a g e 5 | 6

Tank with trees growing at foundation. Inlets and outlets.

Tank interior roof framing in good condition.

Tank interior side wall in fair condition.

P a g e 6 | 6

Tank interior.

Tank floor in fair condition.

ATTACHMENT 1:

Inspection Report from Heerup Engineering

HEERUP ENGINEERING, PC

12825 W. Ballad Drive Sun City West, AZ 85375

Carl V. Heerup II, PE

Tel: (602)451-3275

HE File 2141

EBT

TECHNICAL MEMORANDUM

Elephant Butte Historic District Concrete Tank January 24, 2022

BACKGROUND

Heerup Engineering, PC was engaged to conduct a structural inspection of the concrete water tank at Elephant Butte Historic District. The purpose of the inspection was to determine its suitability for continued operation and to recommend any needed repairs.

The tank is a 50-foot diameter, approximately 20-foot tall circular reinforced concrete water tank with a wooden roof. The tank is reported to be over one hundred years old, having been constructed between 1914 and 1916. This tank stores potable water to serve the Elephant Butte Dam operations and maintenance facility. Its walls are approximately 18-inches thick. It sits on a hill above the southeast end of the dam. A view of the surroundings is shown in Figure

1. An overall view of the tank is shown in Figure 2.

INSPECTION

Mr. Carl V. Heerup II, PE, in conjunction with Mr. Chad Kaufman (Industrial Inspection Group, Inc.), and others, conducted an on-site inspection of the Headworks on January 12, 2022.

The tank had been emptied and cleaned, and an access hole was cut in the roof to provide access for the inspection. A JLG lift was available to assist in accessing the tank. The following observations were made.

From the exterior, the tank shell appeared to be in good condition. It had been stained by what appears to be efflorescence, but the operations staff reported no leaks. (Figure 2). Sounding detected one area of soft pargetting, but the concrete below was intact and hard.

There were a number of spalls on the exterior, but these were only ½” to 2½” deep. One of these, located approximately 5 feet above the base, was 6 inches wide, 2 inches deep and over 10 feet long. (Figure 3)

The vent cupola, a square wooden structure, was in poor condition. It was leaning, sagging, and had broken louvers. (Figure 4)

The roofing, consisting of composite shingles, had utterly failed, with large areas devoid of shingles. (Figure 4)

The roof sheathing, consisting of plywood in some areas and decking in other areas, was in fair condition, but it did show some signs of deterioration, and the fastening to the rafters could not be observed. (Figure 5)

The roof structure consists of 16 trussed rafters, joined by purlins near midspan, which supported (with the wall) 2x intermediate rafters, one between each pair of trussed rafters (Figure 5). The roof structure was in good condition, although there were signs of

Elephant Butte Concrete Tank HE File 2141 January 24,2022 Page 2 some checking (Figure 6), modern repairs in places (Figure 7), and one intermediate rafter was damaged at the end (Figure 8).

The interior shell and the floor had recently been coated with fiberglass-reinforced resin, so the underlying concrete could not be observed.

There is no manway in the shell or the roof, as is required by modern practice.

There is a 6” overflow pipe, but this is installed above the tank shell, so that any excess product will likely go over the wall before it enters the overflow pipe. (Figure 7)

There is a center vent, as well as eave vents, which appear to be functioning and adequate.

ANALYSIS

Based on our experience, inspection, research, and analysis, and within a reasonable degree of engineering certainty, it is our opinion that:

The basic structure is sound and can continue to serve for many more years, provided that certain improvements and repairs, as described below, should be made before returning the tank to service.

The deteriorated condition of the roofing will subject the product water to possible contamination during rain events.

The dilapidated vent cupola is another potential source of contamination. In addition, it may be totally destroyed or removed from the roof in a heavy wind event, exposing the water to major contamination.

The mis-located overflow pipe renders it essentially useless, and an overflow event may cause significant damage to the surroundings.

CONCLUSIONS AND RECOMMENDATIONS

The center vent cupola should be removed and replaced. The replacement may be either a more typical mushroom vent, or a replacement in-kind. If a mushroom vent, it should be securely mounted to the roof structure, either directly or through the (replaced) sheathing. If in-kind replacement, the new cupola should be adequately braced, and the louvers should be made of metal, and configured to minimize the possibility of rainwater intrusion.

A hole should be core-drilled in the side of the tank, at least 6” clear below the top of the shell, and a new overflow pipe installed in the hole, using modular mechanical seal.

The large spall should be repaired, by cutting a rectangular perimeter ½” deep, chipping within that perimeter to a depth of ½” minimum, and patching back with a polymer-modified repair mortar. This technique is detailed in the American Concrete Institute’s Repair Application Procedure #6 (RAP-6), “Vertical and Overhead Spall Repair by Hand Application.” A copy is included as Attachment B.

The roofing should be removed and replaced.

January 24,2022 Page 3

While the roofing and vent have been removed, we recommend that all sheathing be removed and replaced, as well. Because of long spans between rafters, new sheathing should be 2x tongue and groove decking.

While this is being done, an access scuttle should be installed in the roof to permit access without damage to the roof.

Removal of sheathing will allow close examination of rafters. Any damaged rafters should be repaired or removed and replaced.

Heerup Engineering, PC reserves the right to amend our opinions and conclusions should additional information become available.

Please let us know if we can be of any further service on this or future matters.

Regards, HEERUP ENGINEERING, PC

Carl V. Heerup II Principal Engineer Licensed to practice in AZ, CA, FL, & TX

CVH/cvh

Attachment A—Figures Attachment B—ACI RAP-6

January 24,2022 Attachment A—Page 1

ATTACHMENT A

Figures

Figure 1 –Tank location

Figure 2 – Overview of concrete water tank

Butler WRF Hwks HE File 2029 January 9,2022 Attachment A--Page 2

Figure 3 – Large spall

Figure 4 – Vent cupola

January 9,2022 Attachment A--Page 3

Figure 5—Roof rafters and sheathing

Figure 6—Checking in post

January 9,2022 Attachment A--Page 4

Figure 7—Modern repairs (green) and Overflow pipe (red)

Figure 8—Damaged intermediate rafter

986 CONCRETE REPAIR MANUAL

Vertical and Overhead Spall Repair by Hand Application (ACI RAP-6) 1

ACI RAP Bulletin 6

Vertical and Overhead Spall Repair by Hand Application

FIELD GUIDE TO

CONCRETE REPAIR

APPLICATION PROCEDURES

by J. Christopher Ball

987VERTICAL AND OVERHEAD SPALL REPAIR BY HAND APPLICATION

2 Repair Application Procedures Bulletin

Introduction One of the most common application methods for repairing concrete is by hand troweling mortars. This method can be used to repair spalled or deteriorated concrete (Fig. 1) or to resurface vertical, overhead, and horizontal concrete surfaces. Applying repair materials by hand does not require significant equipment and is ideal for shallow surface repairs, especially in areas with limited or difficult access. While both portland cement-based and resin-based repair mortars have been used for trowel-applied vertical and overhead repairs, this field guide focuses on the application of portland cement-based repair materials.

Before any concrete repair is initiated, the root cause of the damage should be determined with a thorough condition survey of the structure. Typical causes of concrete damage can include corrosion of embedded metals from exposure to chloride ions from deicing salts or sea spray in coastal areas;

disintegration from freezing-and-thawing cycles when the concrete is saturated with water; or deterioration from chem-ical attack. Understanding the cause of the deterioration, the owner’s repair objectives, and the in-service environment of the concrete structure will help in the proper selection of repair materials and application methods.

The technique of hand troweling repair mortars requires the selection of a sag-resistant mortar and attention to detail during application to achieve an adequately consolidated repair that is well-bonded to the concrete substrate. The successful installation is a function of good surface prepara-tion, application techniques, curing procedures, and properties of the repair material selected.

What is the purpose of this repair?

Hand-applied repair mortars replace damaged concrete and are generally recommended for thin repairs that are cosmetic in nature. Thin overlays of mortar can also be applied to renovate deteriorated vertical and overhead concrete surfaces. This technique, when properly executed, improves the appearance of the deteriorated structure and provides additional protection to the concrete surface.

When do I use this method?

Structural repair projects generally require other repair methods such as form and cast-in-place, grouted pre-placed aggregate repair, or shotcrete. Experienced workers using wood floats, sponges, or steel trowels can achieve a variety of finishes with trowel-applied mortars. Hand application has been used to repair vertical and overhead surfaces including walls, columns, beams, soffits, and building facades.

Placement thickness can vary depending on the type of materials selected and the size, depth, and orientation of the repair cavity. Placement thickness can range from 1/8 to 2-3/4 in.

(3 to 70 mm) on vertical surfaces, and 1/8 to 1 in. (3 to 25 mm) on overhead surfaces in a single layer. Deeper placements may require repair material to be placed in additional layers.

How do I prepare the surface?

The recommended steps in properly preparing the surface to receive a hand-applied mortar are as follows:

1. Bulk concrete removal and edge conditioning— Loose, delaminated concrete should be removed until the substrate consists of sound concrete (Fig. 2). Where corrosion of the rein-forcement exists, continue bulk removal along the reinforcing steel and adjacent areas with evidence of corrosion-induced damage that would inhibit bonding of repair materials. Bulk concrete removal should include undercutting the corroded reinforcing steel by approximately 3/4 in. (19 mm). The shape of the prepared cavity should be kept as simple as possible–generally square or rectangular in shape. The edges of the patches should be sawcut perpendicular to the surface to a depth of 1/2 in. (13 mm) to avoid feather edging the repair material (Fig. 3).

2. Final surface cleaning— Use abrasive blasting (Fig. 4) to remove residual dust, debris, fractured concrete, and contam-inants that prevent proper bonding. If abrasive blasting is not feasible, pressure washing using a minimum 3000 psi (250 MPa) may be acceptable depending on the bond strength required.

Blowing with oil-free compressed air or alternately, the use of a vacuum, may be appropriate if dust is still present after the blasting. The final surface texture should be rough, with approximately a 1/4 in. (6 mm) amplitude (Fig. 5);

Fig. 1—Concrete delamination.

Fig. 2—Bulk concrete removal.

988 CONCRETE REPAIR MANUAL

Vertical and Overhead Spall Repair by Hand Application (ACI RAP-6) 3

3. Treatment of exposed reinforcement—Bond-inhibiting corrosion should be removed from the reinforcing steel by an abrasive blasting wire wheel or needle scaler. If the cross-sectional area of the reinforcing steel has been significantly reduced, a structural engineer should be consulted. If a rein-forcing steel coating has been specified, apply the coating after the reinforcing steel has been cleaned (Fig. 6).

4. Substrate saturation—Most portland cement-based materials require the base concrete to be in a saturated, surface dry (SSD) condition prior to application to prevent a rapid loss of moisture from the repair material and into the substrate. An SSD condition is achieved when the body of the concrete is saturated and free surface water and puddles have been removed from the surface of the concrete. An SSD surface is not recommended if a polymer bonding agent is to be used. When using polymer bonding agents, follow the manufacturer’s recommended surface preparation require-ments. The general recommendations previously given may be influenced by several factors, including:

• Desired roughness profile of the prepared surface (This may be specified by the manufacturer of the repair product);

• Method of surface preparation, including chipping hammers, abrasive blasting, high-pressure water-blast-ing, or hydrodemolition;

• Possible contamination of the surface by chemicals, oils, or grease; possible carbonation; and methods of removing contaminants or carbonated concrete;

• Repair material manufacturer’s recommendations (Ask for technical data sheets and installation bulletins and read the printed instructions on the packaging.); and

• Treatment of existing cracks and joints.

For additional information, consult the recommendations of the International Concrete Repair Institute (ICRI) Guidelines No. 03732, “Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Overlays,” or No. 03730, “Guide for Surface Preparation for Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion.”

How do I select the right material?

Hand- or trowel-applied repair materials are generally proprietary, prepackaged, cementitious products. Portland cement-based materials designed for hand application may also include polymers, silica fume, shrinkage-compensating materials, and other additives for enhanced physical properties and improved handling.

Specifiers, applicators, and owners can consult ICRI Guide-line No. 03732, “Selecting and Specifying Materials for Repair of Concrete Surfaces,” for a useful checklist for prior-itizing desired material properties. Manufacturers’ technical data sheets should be consulted for material properties.

The physical property requirements such as drying shrinkage, permeability, freezing-and-thawing resistance, and mechanical properties vary from project to project depending on the expected service conditions. The proper-ties critical to the long-term success of the repair should be determined during the evaluation phase and be specified.

Other factors that may influence the selection of repair materials include desired application thickness, rate of strength gain, ease of application, color, and in-place cost.

For some hand-applied repairs, sealers or decorative or protective coatings may be used to provide additional protec-tion to the base concrete, to enhance aesthetics, or both.

When this is the case, confirm the required curing and drying

Fig. 3—Edge conditioning.

Fig. 4—Final surface cleaning.

Fig. 5—Properly prepared surface.

989VERTICAL AND OVERHEAD SPALL REPAIR BY HAND APPLICATION

4 Repair Application Procedures Bulletin time (or maximum moisture content) with the sealer or coating manufacturer before application commences. For more information, consult ACI 515.1R, “Guide to Use of Waterproofing, Dampproofing, Protective, and Decorative Barrier Systems for Concrete.”

What equipment do I need?

Typical equipment needed for hand-applied repair mortars includes:

• A suitable mixer unit such as a drill/paddle/pail combi-nation for small repairs (Fig. 7), or paddle-type mortar mixers for larger applications;

• Air compressor, sawcutting equipment, blades, abrasive blast equipment;

• Water-measuring device to ensure that proper amounts of mixing water are used; and

• Finishing, handling, and testing tools required by the specification or good concreting practices.

Be sure that necessary equipment and tools are on site and in proper working order. Have backup equipment or alter-nate methods planned and available.

What are the safety considerations?

Concrete repair mortars are hazardous materials and should be treated as such. Job-site safety practices should include the following where applicable:

• Applicable material safety data sheets (MSDS) should be on hand;

• Machinery and equipment used must have the correct safety guards and warnings in place;

• Workers should wear protective gloves and other clothing needed to prevent skin contact with wet, highly alkaline cementitious materials;

• A face shield or safety glasses are needed to provide eye protection;

• Eye wash facilities should be available on the job site.

• Dust masks are needed for workers operating or working near the material mixer and forced-air respirators used for abrasive blasting;

• Hearing protection must reduce sound levels reaching the inner ear to limits that are specified by the United States Occupational Safety and Health Administration (OSHA); and

• Confirm that adequate ventilation is available in closed spaces before operating equipment that emits dangerous exhaust fumes.

It is the responsibility of the user of this document to establish health and safety practices appropriate to the specific circumstances involved with its use. ACI does not make any representations with regard to health and safety issues and the use of this document. The user must determine the applicability of all regulatory limitations before applying the document and must comply with all applicable laws and regulations, including but not limited to, United States Occu-pational Safety and Health Administration (OSHA) health and safety standards.

Preconstruction meeting Prior to proceeding with the repair, a preconstruction meeting is recommended. The meeting should include repre-sentatives for the owner, engineer, contractor, materials manu-facturer, and any other parties needed to explain the means, methods, and materials necessary to achieve the repair objec-tives. See ICRI Guideline No. 03733, “Guide to Selecting and Specifying Materials for Repair of Concrete Surfaces.”

Repair procedure

1. Apply the repair material.

• Mix the material following the manufacturers’ recom-mendations;

• Scrub a thin bond coat of the repair mortar into the SSD substrate, thus filling pores to ensure intimate contact and to help prevent sloughing or sagging of repair materials on vertical and overhead surfaces. Alterna-tively, apply a bonding agent if required by the manu-facturer or the repair specification;

• Apply the material with adequate pressure before the bond coat dries (Fig. 8). Thoroughly consolidate the repair material into the corners of the patch and around any exposed reinforcement in the repair zone. Full encapsulation of the reinforcement is important for

Fig. 7—Typical equipment to mix materials.

Fig. 6—Treatment of exposed reinforcement.

990 CONCRETE REPAIR MANUAL

Vertical and Overhead Spall Repair by Hand Application (ACI RAP-6) 5 long-term durability; and

• If a second lift is required, thoroughly roughen the sur-face of the first lift by scoring the soft mortar to achieve an aggressive finish, similar in profile to the prepared concrete substrate. This process will promote additional mechanical bond between lifts. If the second lift will not be immediately applied, keep the first lift moist until application of the second lift. After the first lift has reached final set, moisten the surface of the first lift, scrub in a thin layer of fresh mortar, and apply the second lift of material. Once the desired thickness has been achieved, strike off level with the adjacent concrete.

2. Finish and cure the repair.

• Finish the repair material to produce a final finished appearance as required by the project specifications.

Because of the nonbleeding, “sticky” nature of many of these materials, the use of an evaporation control film may be helpful; and

• As with all portland cement-based materials, proper curing will provide enhanced physical properties. Good curing procedures prevent rapid moisture loss at early ages. Consult the product manufacturer for curing instruc-tions. Curing will generally be conducted in accordance with ACI 308R, “Guide to Curing Concrete.” The use of curing compounds (Fig. 9) that comply with the moisture retention requirements of ASTM C 309, or moist curing are common curing methods.

How do I check the repair?

Requirements may include:

• Before and after photos;

• Confirmation of acceptable surface preparation. This may include observing the surface amplitude profile.

Alternatively, direct tension testing of the prepared sur-face will provide quantitative data regarding the level of surface preparation achieved;

• Material testing performed by a qualified testing agency;

• Sounding the cured repair for delaminations;

• In-place direct tensile bond testing of the hardened, cured repair to the base concrete using methods similar to those described in ICRI Technical Guideline No.

03739, “Guide to Using In-Situ Tensile Pull-Off Tests to Evaluate Bond of Concrete Surface Materials,” pub-lished by the International Concrete Repair Institute.

Important observations include maximum stress, expressed in psi or MPa, and failure mode (base con-crete, bond line, or cohesive failure of the mortar).

References ACI Committee 201, 1992, “Guide for Making a Condition Survey of

Concrete in Service (ACI 201.R-92), American Concrete Institute, Farm-ington Hills, Mich., 16 pp.

ACI Committee 308, 2001, “Guide to Curing Concrete (ACI 308R-01),” American Concrete Institute, Farmington Hills, Mich., 31 pp.

ACI Committee 364, 1994, “Guide for Evaluation of Concrete Struc-tures Prior to Evaluation (ACI 364.1R-94),” American Concrete Institute, Farmington Hills, Mich., 22 pp.

ACI Committee 515, 1985, “A Guide to the Use of Waterproofing, Damp-roofing, Protective, and Decorative Barriers for Concrete (ACI 515.1R-79 (Revised 1985)),” American Concrete Institute, Farmington Hills, Mich., 44 pp.

ACI Committee 546, 2004, “Concrete Repair Guide (ACI 546R-04),” American Concrete Institute, Farmington Hills, Mich., 53 pp.

ASTM C 309, 1998, “Standard Specification for Liquid Membrane- Forming Compounds for Curing Concrete,” ASTM International, West Conshohocken, Pa., 3 pp.

Dorsch, D. F., 1995, “A Guide to Placement Methods for Repair Materials,” Concrete Repair Digest, Dec., pp. 320-325.

Emmons, P., 1993, Concrete Repair and Maintenance Illustrated, RS Means.

International Concrete Repair Institute, 1995, “Guide for Surface Prepa-ration for the Repair of Deteriorated Concrete Resulting from Reinforcing Steel Corrosion,” Technical Guideline No. 03730, 8 pp.

International Concrete Repair Institute, 1997, “Selecting and Specifying Concrete Surface Preparation for Sealers, Coatings, and Polymer Over-lays,” Technical Guideline No. 03732., 41 pp.

International Concrete Repair Institute, 1997, “Guide for Selecting and Con-crete Repair Materials,” Technical Guideline No. 03733, 34 pp.

International Concrete Repair Institute, 1997, “Guide for Using In-Situ Tensile Pull-Off Tests to Evaluate Bond of Concrete Surface Materials,” Technical Guideline No. 03739, 16 pp.

Smoak, W. G., 1997, Guide to Concrete Repair, U.S. Department of the Interior, Bureau of Reclamation Technical Service Center, Apr.

Fig. 8—Hand application of repair material. Fig. 9—Spray application of curing compound.

ATTACHMENT 2:

Inspection Report from Industrial Inspection & Consulting

DAILY INSPECTION REPORT

REPORT #DNR005 - 20220112-1, APPROVED

ELEPHANT BUTTE CONCRETE TANK ASSESSMENT, TRUTH OR

CONSEQUENCES, NEW MEXICO, UNITED STATES

D AND R TANK

GENERAL

PRE-WORK SURFACE CONDITIONS

ENVIRONMENTAL CONDITIONS

Started: 01/12/2022, 8:09 AM MST - Location: 33.15,-107.19 Submitted: 01/18/2022, 4:56 PM MST - Location: 35.05,-106.63 Approved: 01/18/2022, 4:56 PM MST

Report Date: 01/12/2022, MST Description of Items and/or Areas of Work: Interior and Exterior tank assessment.

Photo Description: General picture of the tank.

READING

Description: Environmental Conditions upon arrival. Date / Time: 01/12/2022, 8:15 AM MST Air Temperature: 33.3 °F Wet Bulb Temp.: 28.6 °F RH: 51.8% Dew Point: 19.3 °F Surface Temp: 22.5 °F Delta: 3.2 °F

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 1 of

Photo Description: Ambient temperature

Photo Description: Ambient temperature

Photo Description: Ambient temperature

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 2 of

HOLD POINT INSPECTIONS PERFORMED

PAINTED SURFACE CONDITION

Photo Description: Surface temperature

Pre-Surface Prep / Condition and Cleanliness

N/A Surface Prep Monitoring N/A

Post-Surface Prep / Condition and Profile

N/A Pre-Application Prep / Surface Cleanliness

N/A

Application Monitoring / WFT / Mist Coat

N/A Post-Application / Application Deficiencies

N/A

Post-Cure / DFT / Visual Coverage N/A Nonconformance / Corrective Action Follow-up

N/A

Final Inspection N/A Lighting / Inspections min. 50 ft.

Candles

N/A

Painted Surface Condition (select all that apply): Coating Assessment

Photo Description: General picture of the tank interior.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 3 of

Photo Description: General picture of the tank interior.

Photo Description: General picture of the tank interior.

Photo Description: General picture of the tank interior.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 4 of

Photo Description: General picture of the roof structure.

Photo Description: General picture of the floor.

Photo Description: General picture of the floor.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 5 of

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, significant runs present. This will not effect the performance of the material as applied.

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, significant runs present. This will not effect the performance of the material as applied.

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, significant runs present. This will not effect the performance of the material as applied.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 6 of

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, significant runs present. This will not effect the performance of the material as applied.

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, looks to be thin in some locations.

These areas should be addressed in the future as these locations will eventually allow the wicking do to the soon to be exposed fiberglass fibers.

Photo Description: Picture of the wall/shell of the tank.

Fiberglass resin, looks to be thin in some locations.

These areas should be addressed in the future as these locations will eventually allow the wicking do to the soon to be exposed fiberglass fibers.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 7 of

Photo Description: Timber structure appears to be in good condition from below, structural engineer will verify the structural integrity and make any needed suggestions for repairs.

Photo Description: General picture of the floor.

Photo Description: Roof will need to be replaced as there is significant wear and damaged shingles.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 8 of

Photo Description: Roof will need to be replaced as there is significant wear and damaged shingles.

Photo Description: Roof will need to be replaced as there is significant wear and damaged shingles.

Photo Description: General exterior picture, this area has concrete spalling which will be addressed the the structural report.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 9 of

Photo Description: General exterior picture, this area has concrete spalling which will be addressed the the structural report.

Photo Description: Spalled concrete

Photo Description: Spalled concrete

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 10 of

Photo Description: General picture of the exterior of the tank.

Photo Description: General picture of the exterior of the tank.

Photo Description: General picture of the exterior of the tank.

The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 11 of

INSTRUMENT HISTORY SHEET

Photo Description: General picture of the exterior of the tank.

INSTRUMENTS

Instrument Type: Dewpoint Meter Serial Number: 44840756 Instrument Brand: Fluke Instrument Model: 971 Calibration Due: 08/25/2022, MDT Completed By: National Calibration Lab

INSTRUMENTS

Instrument Type: Surface Temperature Gage Serial Number: 93831983 Instrument Brand: Fluke Instrument Model: 62 Mini Calibration Due: 08/23/2022, MDT Completed By: National Calibration Lab

INSTRUMENTS

Instrument Type: Dry Film Thickness Gage Serial Number: 439116 Instrument Brand: DeFelsko Instrument Model: PosiTector 6000 advanced Calibration Due: 12/09/2022, MST Completed By: New from manufacture

INSTRUMENTS

Instrument Type: Surface Profile Serial Number: 15002484 Instrument Brand: Mitutoyo Instrument Model: Absolute Calibration Due: 07/19/2022, MDT Completed By: National Calibration Lab

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The information contained herein is confidential and cannot be reproduced or distributed without prior written consent. © 2022 Page 13 of

REMARKS AND SIGNATURES

DAILY INSPECTION REPORT APPROVAL SIGNATURES

Remarks: The tank should be re-evaluated within the next 5 years as typically recommended for a coating system of this age. Due to the current coating system installed (fiberglass mat with impregnated resin) we would recommend installing a Geotextile system so that the entire fiberglass system does not need to be removed. By installing this type of system there should be a significant savings in the removal cost of the previous coating. There are a few manufactures that we can recommend for the system and would welcome their input as to the specific system they would recommend for the structure. we can facilitate gathering the systems from the various manufactures recommended system to be installed. I would like to wait until we have received the structural assessment of the structure to present that to the coating manufactures so that they have as much information as possible so that they can design and present the most cost effective system available.

Name: Chad Kauffman Date: 01/18/2022, 4:56 PM MST Next Inspection Date: N/A Comment: N/A

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