CVG_OWS_Refresh_Report_06.27.2025_DRAFT.pdf

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT i

DRAFT

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT ii

In May 2025, the Kenton County Airport Board (KCAB) contracted Woolpert, Inc. to perform a refresh of the previous 2021 Oil Water Separator (OWS) condition assessment report. The OWSs are located in various locations on the airfield at the Cincinnati/Northern Kentucky International Airport

(CVG). The goal was to locate each OWS and assess its condition via confined space entry or pole camera visuals. The intended results of the assessment would yield an overall condition rating for each

OWS, identify any necessary improvements, and provide a repair or replacement strategy.

Each OWS was given an asset condition rating of either 1 (good), 2 (fair), or 3 (poor). The OWSs with a condition level of 3 (poor) will be the most critical to address before others.

Woolpert conducted an OWS condition assessment in 2021, inspecting 18 OWSs. For the 2025 reassessment, the focus was specifically on the OWSs that had previously received an asset condition rating of 1 (good) or 2 (fair) to determine if their condition had changed. It was assumed that the OWSs rated as 3 (poor) remained unchanged. Consequently, Woolpert reassessed nine of the original OWSs and included two additional OWSs in this refresh report.

This assessment provided a limited visual assessment of the general structural and maintenance condition of each OWS. The results are not intended to warrant or certify that leaks of fuel, oils, or other potential contaminants will not occur.

Additionally, Connico provided an updated Rough Order of Magnitude (ROM) cost estimate for the OWS repairs/replacements. Further details regarding the cost estimate can be found in Section 5 and in

Appendix B of this report.

Of the OWSs that were reassessed, only one, OWS #17, had a reduced asset condition rating from 2

(fair) to 3 (poor).

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT iii

Table of Contents 1 Introduction

2 Method of Inspection

2.1 Attributes Collected

2.2 Asset Condition Ratings

3 OWS Sizing Review

3.1 Pipe Sizing

3.2 Drainage Area

4 Results

5 Rough Order of Magnitude Cost Estimate

6 Conclusion

Appendix A – Inspection Reports

OWS 1

OWS 2

OWS 4A & B

OWS 5 – Not Assessed in 2025

OWS 6 - Not Assessed in 2025

OWS 7

OWS 8 - Not Assessed in 2025

OWS 9 - Not Assessed in 2025

OWS 10 - Not Assessed in 2025

OWS 11 - Not Assessed in 2025

OWS 12 - Not Assessed in 2025

OWS 14

OWS 15 - Not Assessed in 2025

OWS 17

OWS 26

OWS 27 – Not Assessed in 2025

OWS 29 - Not Assessed in 2025

OWS 32

OWS 33

Appendix B –Rough Order of Magnitude (Rom) Cost Estimate

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT iv

Acronyms and Abbreviations

Connico Connico, LLC (subcontractor)

CVG Cincinnati/Northern Kentucky International Airport

DEM Digital Elevation Model

H2S Hydrogen Sulfide Gas

KCAB Kenton County Airport Board

N/I Not Inspected

OWS Oil Water Separator

ROM Rough Order of Magnitude (cost estimate)

TFR Treatment Flow Rate

Woolpert Woolpert, Inc.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 1

1 INTRODUCTION

In May 2025, the Kenton County Airport Board (KCAB) engaged Woolpert, Inc. to complete a refresh of a prior 2021 condition assessment report of the Oil Water

Separators (OWS) located in various locations around the airfield at the

Cincinnati/Northern Kentucky International Airport (CVG). An OWS is used to treat contaminated water, primarily in areas where oil and water mix, such as stormwater runoff in fueling or maintenance areas. The primary goal is to prevent oil and other contaminants from entering the natural environment, ensuring regulatory code compliance.

The majority of the OWSs are situated in various locations around the airfield, primarily in the ramp areas, and vary in structure type, size, and age. The locations of the assessed OWSs are shown in Figure

1, below. KCAB maintains approximately 20 OWSs, while various tenants maintain an additional 12. In

2021, Woolpert inspected 17 of the 20 OWSs maintained by KCAB/CVG.

The assessment team recorded existing conditions, identified deficiencies, and documented corrective actions and quantities. Each OWS received an asset condition rating of either 1-Good, 2-Fair, or 3-Poor.

These asset condition ratings are further described in Section 2.2.

For capital planning purposes in 2025, KCAB requested Woolpert to update the 2021 OWS report, focusing solely on reassessing the OWSs rated as 1-Good or 2-Fair. Thus, the OWSs that received an asset condition rating of 3 (Poor) were excluded from this reassessment. A side-by-side comparison of the assessment results from 2021 to the present is depicted in Table 1 below.

Table 1: Asset condition ratings, then and now.

OWS # 2021 2025

1 2-FAIR 1-GOOD

2 2-FAIR 2-FAIR

4A 2-FAIR 2-FAIR

4B 2-FAIR 2-FAIR

5 3-POOR Not included

6 3-POOR Not included

7 2-FAIR 2-FAIR

8 3-POOR Not included

9 3-POOR Not included

10 3-POOR Not included

11 3-POOR Not included

12 3-POOR Not included

14 2-FAIR 2-FAIR

15 1-GOOD 1-GOOD

17 2-FAIR 3-POOR

26 2-FAIR 2-FAIR

27 1-GOOD Not included

29 3-POOR Not included

32 Not included 1-GOOD

33 Not included 1-GOOD

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 2

Figure 1: Location of OWSs and asset condition ratings.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 3

2 METHOD OF INSPECTION

To complete the assessment of the OWSs, Woolpert used two data collection methods:

confined space entry and pole camera inspections. Champion, the pumping and cleaning contractor, removed the water and sediment from the OWSs and pressure-washed the interior components and walls to facilitate visual inspections. Woolpert conducted inspections via man entry when conditions permitted. If entry was not feasible, Woolpert utilized a pole camera to inspect the tanks. Regardless of the method used, photographs were taken and attributes were collected to document the condition of the OWSs. Photos and additional inspection information for each OWS can be found in Appendix A.

2.1 Attributes Collected

Prior to commencing the field assessment, Woolpert collaborated with KCAB/CVG staff to identify which attributes of the OWSs were critical for their operations and maintenance needs. The collected attributes included, but were not limited to:

■ Weather conditions

■ Tank number

■ Manufacturer

■ Structure shape and size

■ Structure material

■ Location of structure

■ Year the structure was installed

■ Date of inspection

■ Date the structure was pumped clean

■ Permanent pool depth

■ Sediment depth in inches

■ Cracks and/or displacements

■ Joint failure

■ Loss of joint material

■ Leaking

2.2 Asset Condition Ratings

The assessment team recorded existing conditions, identified deficiencies, and documented corrective actions and quantities. The OWSs were compiled and ranked according to three condition levels. OWSs with a 3-Poor rating are the most critical to address before others. The three condition ratings are further described below.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 4

The OWS has no visible structural damage or damage to the components. The device appears to operate and function as designed. There is a minimal amount of sediment and debris in the structure. Recommended to be inspected biannually.

The OWS has minor structural damage or minor damage to components. Filters or coalescing plates need to be cleaned, but the device is currently functioning as designed. There is a more moderate amount of sediment or debris in the structure. It is recommended to inspect the OWS annually and make repairs as appropriate.

The OWS has severe structural damage or severe damage to the components. Filters or coalescing plates need immediate attention due to being clogged with sludge and sediment. There is moderate to severe groundwater infiltration from the wall of the tank. The device is not operating and functioning as designed. It is recommended to make the necessary repairs or replace them immediately.

3 OWS SIZING REVIEW

Woolpert reviewed the capacity of each KCAB-owned OWS with respect to the surrounding infrastructure and area to identify any improperly sized OWSs. This effort involved two components: 1) verifying that the incoming pipe sizes are suitable for the size of each OWS and 2) ensuring that each

OWS is appropriately sized to manage its entire drainage area.

3.1 Pipe Sizing

The first step was to confirm that the incoming pipe sizes were appropriate for the size of the OWS.

Using data obtained from the Woolpert-performed field inspection and the stormwater system inventory as provided by CVG staff, the inlet pipe of each tank was compared to the outlet pipe of the immediate upstream junction box or diversion box. This comparison served as an indicator of whether the inlet pipe to the OWS had sufficient capacity to manage the stormwater flow being conveyed by the upstream pipe. The inlet and outlet pipe sizes for all tanks were verified for proper sizing using the sizing chart provided in the Highland Tank Oil/Water Separator Sizing Guide. Of the 17 OWSs maintained by

CVG, four were manufactured by Highland Tank & Manufacturing Company, Inc. Highland Tanks provides a pipe sizing chart for their tanks and this chart was used to verify all tanks as being Highland.

The manufacturer of the additional 13 OWSs was not identified. In those cases, Woolpert utilized the

Highland Tank data as an indicator that the inlet pipe may be of an appropriate size. Further investigation of the tank manufacturer is needed to verify proper sizing.

Two tanks demonstrated inconsistency with Highland Tank sizing. The incoming pipe size for Tank 26 is undersized. The tank can handle a greater flow than the incoming pipe allows, but this does not impact the performance of the OWS. Tank 14 has two incoming pipes (one 12-inch pipe and one 30-inch pipe), and only one is sized appropriately to handle the OWS tank size. According to the Highland Tank sizing chart, the OWS should be designed for a 12-inch maximum inlet and outlet pipe diameter. The 30-inch inlet pipe is larger than this OWS can handle, which may indicate that it is receiving more flow than it can handle. Therefore, Tank 14 may require further analysis. The incoming and outgoing pipe data for each OWS can be found in Table 2.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 5

3.2 Drainage Area

The second step of this analysis was confirming the drainage area for each OWS. Each OWS’s drainage area should align with its respective Treatment Flow Rate (TFR) according to the formula provided by

Highland Tank, where 𝐴 represents the drainage area of the tank and 𝑅 is the 10-year, 1-hour rainfall

(1.99”):

𝐴 × 𝑅 × 1.0104 = 𝑇𝐹𝑅

Woolpert attempted to delineate the watershed draining into each OWS by using a Digital Elevation

Model (DEM) provided by KyFromAbove and by using the KCAB-provided stormwater system inventory data. However, nine OWSs and their surrounding drainage systems were not included in the stormwater system inventory, necessitating too many assumptions to accurately delineate watersheds for those

OWSs as well as neighboring OWSs with intersecting drainage areas. Additionally, some OWSs were designed with upstream flow diversion boxes. There was insufficient available design data for each of these diverter boxes to quantify the flow from each drainage area being directed to each OWS.

As noted, the stormwater system inventory provided by CVG did not include the locations of some of the OWSs identified during the inspection. Additionally, pipe segments were found to be incorrectly labeled, and much of the data was not correctly connected. The system inventory map was unclear regarding the flow diversion designs and the intended treatment areas for the OWSs. Due to this lack of information, many assumptions were made throughout the analysis. A thorough update to the airport’s system inventory is crucial before providing an accurate analysis of the OWSs on the facility.

To assist in any further investigation of the allowable treatment area, a back-calculation determined the maximum drainage area that each OWS can treat. Again, the Highland Tank sizing chart was used to determine the TFR and allowable drainage area for all OWSs (i.e., both Highland and unknown tanks) based on tank field measured sizes. These areas are further tabulated in Table 2 below.

Table 2: OWS pipe data.

Tank number

Incoming pipe data

Outgoing pipe data

Flow diversion box?

Is the inlet pipe sized properly?

Maximum drainage area (ac)

1 48” RCP, 30” RCP 48” RCP No Yes 3.33

2 36” RCP, 15” RCP 36” RCP Unknown Yes 2.77

4-A 12” DIP 72” RCP Yes Yes 0.89

4-B 14” DIP 12” DIP Yes Yes 0.89

5 14” DIP 14” DIP Yes Yes 1.66

6 4” DIP 4” DIP Unknown Yes 0.11

7 4” PVC 4” DIP Unknown Yes 0.11

8 20” DIP 20” DIP Yes Yes 3.33

9 18” DIP 15” DIP Unknown Yes 3.33

10 20” DIP 24” DIP Yes Yes 4.44

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 6

Tank number

Incoming pipe data

Outgoing pipe data

Flow diversion box?

Is the inlet pipe sized properly?

Maximum drainage area (ac)

11 18” DIP 20” DIP Yes Yes 3.33

12 18” DIP 18” DIP Unknown Yes 0.55

14 30” RCP, 12” RCP 30” RCP

Yes (before 12” pipe only) No 1.33

15 4” PVC Unknown No Yes 0.33

17 15” DIP 15” DIP Unknown Yes 0.78

26 10” PVC Unknown Unknown No 1.66

27 4” PVC 4” PVC Unknown Yes 0.11

29 4” PVC 4” PVC Unknown Yes 0.03

32 4” PVC 4” PVC No Unknown Unknown

33 8” Iron, 3” Iron 8” Iron Yes Unknown Unknown

4 RESULTS

A high-level overview of the data captured during the assessment can be found in Tables 3 and 4, below. Table 3 shows general information for each OWS, including the structure shape, dimensions, volume, structure material and year installed. Table 4 provides an overview of the asset condition rating for each tank and certain attributes collected during the assessment. It is also important to note that there is no guarantee that tanks are not leaking and causing groundwater contamination.

While reviewing the table below, it is important to note that the typical life span of an OWS is 15-20 years. Some may last longer with proper maintenance, but as they age, the risk of leaks and groundwater infiltration rises. Newer OWSs are being designed with double-walled steel material with built-in leak prevention technology to help further preserve the life of the units.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 7

Table 3: OWS general information.

OWS # Manufacturer Structure shape Structure length (feet) Structure width (feet) Structure height (feet) Volume (gallons)

Structure material General location

Year installed

1 Unknown Rectangular 24’8” 13” 14’4” Unknown Concrete Ramp 1 at Block 1E 1987

2 Unknown Rectangular 24’ 13’ 11’2” Unknown Concrete Ramp 1 at A-12 1983

4A/B Unknown Rectangular 16’4” 7’ 10’4” Unknown Concrete Terminal Drive West of Radisson Inn 1990

5 Unknown Round 25’6” 10’ 10’ Unknown Steel Terminal Drive West of Radisson Inn 1990

6 Unknown Rectangular 4’ 3’6” 8’2” 1,000 Concrete Northeast Corner of Field Maintenance 1990

7 Unknown Rectangular 9’ 4’6” 4’6” 1,000 Concrete Southwest Corner of Field Maintenance 1990

8 Highland Round Unknown 10’ 10’ 30,000 Steel Ramp 3 South of Gate B-13 1992

9 Highland Round Unknown 10’ 10’ 30,000 Steel Ramp 3 South of Gate C-8/C-10 1992

10 Highland Round Unknown Unknown Unknown 40,000 Steel Taxiway F, Northeast Block of 3F 1992

11 Highland Round Unknown 10’ 10’ 30,000 Steel Taxiway G, Northwest of Block 3G 1992

12 Unknown Round 24’ 6’ 6’ 5,000 Steel Island between Taxiway J and K, West of Taxiway F 1993

14 Unknown Rectangular 20’ 8’ 11’1” Unknown Concrete Meyer Tool Ramp, West of Ramp 1999

15 Unknown Rectangular 9’ 4’6” 5’ 3,000 Concrete Ameriflight Hangar 2000

17 Unknown Rectangular 16’ 8’ 8’1” Unknown Concrete Kenton Road (inside of AOA), East of Delta Hangar at Blast Fence

Unknown

26 Unknown Round 24’1” 9’10” 9’10” 15,000 Steel Field Maintenance Fuel Farm 2007

27 Unknown Rectangular 7’6” 5’6” 5’ 1,000 Concrete Field Maintenance Cold Storage 2005

29 Unknown Rectangular 7’10” 4’9” 5’ 500 Concrete Standard Parking 2007

32 Unknown Round 4’ 6’ 564 Concrete SE Corner of Facilities Maintenance Building Unknown

33 Unknown Round 20’ 8’ 8’ 7520 Steel Gate A-2 Unknown

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 8

Table 4: OWS assessment data.

* It is assumed that the asset condition ratings for the OWSs rated as 3-Poor in 2021 have remained unchanged.

OWS

2021 asset condition ratings 2025 asset condition ratings

Evidence of H2S deterioration of access structure?

Top slab cracked or spalling?

Sediment present?

Sediment depth (inches)

Oil present?

Oil depth (inches)

Has trash and debris accumulated?

Cracks and/or displacements?

Minor spalling

(1” or less)

Major spalling

(exposed rebar)

1 Yes Yes Yes, 6” No, 0” No No Yes No

2 Yes Yes No, 0” No, 0” No No No No

4A/B No No No, 0” No, 0” No No No No

5 Not included* No No No, 0” No, 0” No No No No

6 Not included* No No No, 0” No, 0” No No No No

7 No No Yes, 3” No, 0” No No Yes Yes

8 Not included* Yes No No, 0” No, 0” No No No No

9 Not included* Yes Yes Yes, 10” No, 0” No No Yes No

10 Not included* Yes No N/I No, 0” No No No No

11 Not included* Yes No No, 0” No, 0” No No No No

12 Not included* Yes Yes No, 0” No, 0” No No No No

14 No Yes No, 0” No, 0” No No No No

15 No N/I Yes, 1” No, 0” No No No No

17 Yes No No, 0” No, 0” No No No No

26 No No No, 0” No, 0” No No No No

27 Not included* No N/I Yes, 3” No, 0” No No No No

29 Not included* No Yes Yes, 3” No, 0” No No No No

32 Not included No No No, 0” No, 0” No No No No

33 Not included Yes No No, 0” No, 0” No No No No

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 9

5 ROUGH ORDER OF MAGNITUDE COST ESTIMATE

Prior to Woolpert completing the reassessment of the OWSs in 2025, KCAB asked that Connico, LLC, a Woolpert subcontractor, provide an updated Rough Order of Magnitude

(ROM) cost estimate for the recommended repairs and replacements of the OWSs. It is important to note the following:

■ For the OWSs that had an asset condition rating of 3-Poor, Connico provided two cost estimates:

one for the complete replacement of components and another for the recommended actions specified in Woolpert’s 2021 OWS assessment report.

■ For the OWSs with a condition rating of 2-Fair and 1-Good, Connico provided a ROM cost estimate for the recommended action only as outlined in Woolpert’s 2021 OWS assessment report.

■ The full OWS replacement cost only includes the replacement of all components and does not include the replacement of the tank itself. For OWS No. 10, however, the cost of the tank was included because Woolpert did recommend replacing this tank.

■ OWS Nos. 32 and 33 were not included in the ROM cost estimate as they were not previously included in the 2021 assessment report.

■ Markups and soft costs were added to the cost estimate and are further described in Connico’s report.

The ROM cost estimate can be viewed in Appendix 2.

6 CONCLUSION

In conclusion, this project provided a good baseline assessment for KCAB’s OWSs. It is recommended that KCAB completes all suggested repairs and create a standard inspection schedule to stay ahead of deferred maintenance issues. It is also recommended that KCAB complete a full stormwater system inventory. The inventory will provide a detailed depiction of all assets within the stormwater collection system and how they work together. The inventory data could also be used to model storm events to ensure the system is properly sized and functioning as designed.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 10

APPENDIX A – INSPECTION REPORTS

Inspection reports for each OWS inspected by Woolpert are on the following pages. The reports include a summary of findings, condition of components, and an overall condition rating of 1-Good, 2-Fair, or 3-Poor.

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 11

OWS 1

Condition Rating:

OWS 1 was cleaned and inspected on 05/01/2025.

Champion pumped out and cleaned most of the water from the OWS, leaving only about 4 inches of water remaining, which allowed Woolpert to safely perform a confined space entry into the structure. OWS 1 is located in the middle of a taxiway, which required

CVG to temporarily shut down the area to allow for inspection and cleaning. The tank is made of concrete, rectangular in shape, and 24 feet 8 inches in length, 13 feet in width, and 14 feet 4 inches in height. The permanent pool in the OWS is approximately 88 inches deep. During the inspection, it was observed that rust and corrosion on the steps might indicate the presence of H2S gas. A confined space report was created, and gas levels were checked and continuously monitored during and before entry into the

OWS. All debris, sediment, and rocks were removed by Champion prior to cleaning, and the entire structure appeared to be in good condition. All incoming and outgoing pipes and the baffle wall were in good condition, and there was no visual evidence of structural damage to the OWS interior. The top slab on the outside of the OWS had separation from the surrounding concrete and may need to be resealed.

RECOMMENDED ACTION: Inspect overall tank condition annually, monitor leaks twice yearly, and seal as appropriate.

OWS 1, Photo 1

CA S-48 Inch Coming Into OWS and Missing Steps

OWS 1, Photo 2

CA—48 Inch Incoming Pipe and

East Wall

OWS 1, Photo 3

CA-W-30 Inch Incoming Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 12

OWS 2

OWS 2 was cleaned and inspected on 04/30/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. OWS 2 is located at Gate A12 under the jetway, which required the gate to be temporarily shut down to allow for the inspection and cleaning. The tank is made of concrete, rectangular in shape, and 24 feet in length, 13 feet in width, and 11 feet 2 inches in height. The permanent pool in the OWS is approximately 89 inches deep.

During the inspection, it was determined that there could be a presence of H2S gas due to the rust and corrosion present on the steps. All pipes and the baffle wall were in good condition, and there was no visual evidence of structural damage to the OWS interior. The top slab on the outside of the OWS has separation from the surrounding concrete and has been sealed in the past, but may need to be resealed.

RECOMMENDED ACTION: Inspect overall tank condition annually, monitor top slab twice yearly, and reseal as appropriate.

OWS 2, Photo 4

CA-E-36 Inch Incoming Pipe

OWS 2, Photo 5

CC-S-Rust and Corrosion on

Steps

OWS 2, Photo 6

CA-S-Incoming Pipes and

Steps

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 13

OWS 4A & B

OWS 4 was cleaned and inspected on 04/29/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. Water was refilling the tank at a significant rate during the inspection. There was about 16 inches of water at the start of the inspection and approximately 24 inches of water by the end of the inspection. The tank is made of concrete, rectangular in shape, and has a length of

16 feet 4 inches, a width of 7 feet, and a height of 10 feet 4 inches. The permanent pool in the OWS is approximately 77 inches deep. Two 72-inch RCP pipes exit the OWS on the north side of a wall within the structure, which is elevated 5 feet 7 inches above the tank’s bottom. Both pipes are filled with water, suggesting there could be obstructions not allowing the pipes to drain properly. The presence of obstructions could not be confirmed during the inspection. The

OWS had no evidence of H2S gas, and all components in the OWS had no visual evidence of structural damage.

RECOMMENDED ACTION: Inspect overall tank condition annually, perform CCTV inspection of the pipes to investigate possible obstruction, and add an elbow to the incoming pipe to divert flow to the bottom of the unit.

OWS 4, Photo 7

CA-W-View from East to West

OWS 4, Photo 8

CA-E-Incoming Pipe

OWS 4, Photo 9

CA-Manhole on East Side of Tank

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 14

OWS 5 – Not Assessed in 2025

OWS 5 was cleaned and inspected on 10/26/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. Water from the adjacent stream was refilling the tank at a significant rate during the inspection. During the inspection, approximately 18 inches of water were present in the tank. The tank is made of steel, cylindrical in shape, and measures 25 feet 6 inches in length, 10 feet in width, and 10 feet in height. The permanent pool in the OWS is approximately 162 inches deep. The tank appears to stay full and fills into the manhole access area up to 3 feet above the actual tank. The OWS has coalescing plates that require maintenance. Several plates are dislodged from their rack, and most of them have a significant amount of remaining sludge after being cleaned. Rust and corrosion are present on some of the plates. Both the inlet and outlet pipes, as well as the baffle, are in good condition, and there is no remaining sediment in the tank following the cleaning.

RECOMMENDED ACTION: Replace broken and rusted coalescing plates.

OWS 5, Photo 10

CA-E Dislodged Plates

OWS 5, Photo 11

CA-E-Coalescing Plates Rust and Corrosion

OWS 5, Photo 12

CA-W-Underside of Diffusion Baffle

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 15

OWS 6 - Not Assessed in 2025

OWS 6 was cleaned and inspected on 11/05/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry was not required to conduct a thorough inspection of the structure.

Pictures of the interior of the OWS were taken with an iPad from the top. The tank is concrete, rectangular in shape, and has a length of 4 feet, a width of 3 feet 6 inches, and a height of 8 feet 2 inches. The permanent pool in the OWS is approximately 79 inches deep. Water is infiltrating the OWS from three different walls of the structure, filling the structure at a significant rate. This could lead to more significant leaks and damage if not repaired. There is no elbow on the incoming pipe to direct the incoming flow towards the bottom of the tank. The incoming and outgoing pipes are in good condition, and there is no evidence of H2S gas present.

RECOMMENDED ACTION: It is recommended to seal leaking joints and add an elbow to help divert incoming flow to the bottom of the tank.

OWS 6, Photo 13

Exterior

OWS 6, Photo 14

CA-S-Water Infiltrating Tank on South Wall

OWS 6, Photo 15

CA-N-Outgoing Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 16

OWS 7

OWS 7 was cleaned and inspected on 04/28/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry could not be performed due to obstructions in both manhole access points. The inspection was performed, and pictures of the interior of the OWS were obtained utilizing a pole camera. The tank is concrete, rectangular in shape, and has a length of 9 feet, a width of 4 feet 6 inches, and a height of 4 feet 6 inches. The permanent pool in the OWS is approximately 50 inches deep. During the inspection, the water depth in the OWS was 2 inches, and the sediment depth was 4 inches. Some sediment in the

OWS could not be completely removed because it was heavily compacted and inaccessible. There is some minor spalling on the interior of the top slab, along with a small area where rebar is exposed in the headwall. This does not appear to be a major issue at the present time, but should be monitored for future maintenance. Both the incoming and outgoing pipes are in good condition, but the cleanouts directly beside the OWS in the parking lot do not have covers. There is no evidence of H2S gas in the structure.

RECOMMENDED ACTION: Inspect overall tank condition annually and monitor spalling.

OWS 7, Photo 16

CA-W-Deteriorating Top Slab

OWS 7, Photo 17

CA-E-Sediment

OWS 7, Photo 18

Incoming Pipe Cleanout with No Cover

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 17

OWS 8 - Not Assessed in 2025

OWS 8 was cleaned and inspected on 11/4/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry was performed in

Chamber A only and could not be performed in

Chambers B and C. Chamber B was obstructed by the filters, and Chamber C was too small to access.

Pictures of the interior of Chambers B and C were taken with a pole camera. The tank is made of steel, cylindrical in shape, with a width of 10 feet and a height of 10 feet. The overall length of the OWS could not be determined due to inaccessibility to Chambers

B and C. Chamber A has a length of 21 feet 6 inches.

The permanent pool in the OWS is approximately 102 inches deep. After being cleaned, there was approximately 2 inches of water in the OWS during the inspection. The coalescing plates and filter media are both filled with sludge, and the filter media is dislodged in areas. Evidence of H2S gas is visible on the steps and within the access locations where rust and corrosion are present. The inlet and outlet pipes appear to be in good condition, but the outlet pipe could not be fully inspected. The coalescing plates and filters need to be maintained to allow the structure to function as designed.

RECOMMENDED ACTION: Replace or repair coalescing plates and filters, and monitor corrosion.

OWS 8, Photo 19

CC-N-Chamber C Manhole Access

OWS 8, Photo 20

CA-W-Sludge in Coalescing Plates

OWS 8, Photo 21

CA-Incoming Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 18

OWS 9 - Not Assessed in 2025

OWS 9 was inspected on 11/1/2021. CVG pumped the tank down to allow Woolpert to perform the inspection. Champion was unavailable at the time to clean OWS. Confined space entry was performed in

Chamber A only and could not be performed in

Chambers B and C. Chamber B was obstructed by a baffle wall, and Chamber C was too small to access.

Pictures of the interior of Chambers B and C were taken with a pole camera, but with limited visibility.

The tank is made of steel, cylindrical in shape, with a width of 10 feet and a height of 10 feet. The overall length of the OWS could not be determined due to inaccessibility to Chambers B and C. Chamber A has a length of 21 feet 6 inches. The permanent pool in the

OWS is approximately 102 inches deep. After Champion pumped the water down, about 12 inches of water remained in the OWS during the inspection. The coalescing plates and filter media are covered with sludge and need to be cleaned. Evidence of H2S gas is visible on the steps and all the access points where there is rust and corrosion present. The top slab on the exterior of the OWS has some cracking that has been sealed.

RECOMMENDED ACTION: Replace or repair coalescing plates and filters. Seal the exterior slab and monitor corrosion.

OWS 9, Photo 22

CA-NW-Corrosion

OWS 9, Photo 23

CA-SW-Liner Peeling Off Tank Wall

OWS 9, Photo 24

CA-W-Sediment Visible

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 19

OWS 10 - Not Assessed in 2025

OWS 10 was inspected on 11/2/2021. There was an attempt to pump the tank clear of water, but there was significant inflow that was refilling the tank.

Confined space entry could not be performed.

Therefore, a pole camera was utilized to visually inspect the components of the OWS. It was difficult to fully inspect the OWS with the pole camera due to having to fit the camera into tight spaces with limited ability to adjust to different angles. During the inspection, it was determined that significant portions of the filter media were completely missing. There was evidence of the presence of H2S gas in the access points and on the steps, where rust and corrosion were visible. Additional rusting was visible in areas of the tank’s walls. The OWS is steel and cylindrical. The dimensions of the tank and the permanent pool depth could not be determined, and the incoming pipe in Chamber A was not visible due to being behind a baffle wall.

RECOMMENDED ACTION: Replace missing filter media and monitor corrosion.

OWS 10, Photo 25

CC-S-Rust and Corrosion

OWS 10, Photo 26

CB-W-Missing Filter Media

OWS 10, Photo 27

CB-E-Damaged Filter Media

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 20

OWS 11 - Not Assessed in 2025

OWS 11 was cleaned and inspected on 11/3/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry was performed in

Chambers A and B only, and could not be performed in Chamber C. Chamber C was too small to access.

Pictures of the interior of Chamber C were taken with a pole camera. The tank is made of steel, cylindrical in shape, with a width of 10 feet and a height of 10 feet.

The overall length of the OWS could not be determined due to inaccessibility to Chamber C.

Chambers A and B have a combined length of 47 feet

7 inches. The permanent pool in the OWS is approximately 84 inches. After being cleaned, there was about 4 inches of water in the OWS during the inspection. The coalescing plates and filter media are both filled with sludge, and the filter media is dislodged in areas and completely missing in others.

Evidence of H2S gas is visible on the steps and within the access locations where rust and corrosion are present. There is some deterioration of the tank’s liner along with some rusting of the tank’s walls. The inlet and outlet pipes appear to be in good condition; however, inspectors were unable to assess the outlet pipe in Chamber C fully. The coalescing plates and filters need to be maintained to allow the structure to function as designed.

RECOMMENDED ACTION: Replace or repair coalescing plates and filter media. Monitor for corrosion and deterioration.

OWS 11, Photo 28

CC-E-Chamber C Manhole Access

OWS 11, Photo 29

CB-N-Sludge in Coalescing Plates

OWS 11, Photo 30

CB-S-Missing Filter Media

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 21

OWS 12 - Not Assessed in 2025

OWS 12 was cleaned and inspected on 10/27/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. About 3 inches of water remained in the structure during the inspection. The tank is made of steel, cylindrical in shape, and measures 24 feet in length, 10 feet in width, and 10 feet in height. The entire interior of the

OWS has rusting and corrosion. The coalescing plates are completely gone, and the rack that holds them is severely deteriorating. All components are coated with sludge and are non-functional. The OWS is not functioning as designed and needs immediate attention.

RECOMMENDED ACTION: Replace OWS.

OWS 12, Photo 31

CA-East-Manhole Access

OWS 12, Photo 32

CA-W-Coalescing Plate Rack Corrosion

OWS 12, Photo 33

CA-Incoming Pipe Looking Up from Bottom

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 22

OWS 14

OWS 14 was cleaned and inspected on 04/29/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. Less than 1 inch of water remained in the structure during the inspection. The tank is a concrete, rectangular structure with a length of 20 feet, a width of 8 feet, and a height of 11 feet 1 inch. The permanent pool in the OWS is approximately 86 inches. The interior of the OWS was in good condition except for a minor collection of debris in the outfall chamber. The debris consisted of pieces of 2X4 and other construction debris that should be removed next time the structure is cleaned to prevent pipe blockages. A small gap beneath the outgoing pipe should be sealed to make sure water isn’t able to leak out from the structure. The southernmost manhole slab exhibited signs of spalling and deterioration. The exterior of the top slab of both manhole access points had some severe deep cracking through the entire slab and should, at a minimum, be sealed. The cracking could be due to having a heavy fueling truck parked over the OWS regularly, as well as from the effects of freezing and thawing over the years. The CAD drawings, as provided by CVG, label OWS 14 as a fuel separator.

RECOMMENDED ACTION: Inspect overall tank condition annually, fill void beneath outlet pipe, seal or repair concrete slab, and remove debris from chamber.

OWS 14, Photo 34

CA-S-Debris

OWS 14, Photo 35

CC-S-Outgoing Pipe

OWS 14, Photo 36

CC-S-Chamber C Cracking

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 23

OWS 15 - Not Assessed in 2025

OWS 15 was cleaned and inspected on 10/26/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry could not be performed due to the small size of the manhole access point. Pictures of the interior of the OWS were taken with a pole camera. The tank is a concrete, rectangular structure with a length of 9 feet, a width of 4 feet 6 inches, and a height of 5 feet. The permanent pool depth in the OWS could not be determined. During the inspection, the water depth in the OWS was 1 inch, and the sediment depth was 1 inch. The outlet pipe could not be inspected due to being recessed and behind the baffle wall. The overall condition of the OWS was good and appeared to have no significant issues. A minor amount of sludge and debris remained in the tank after cleaning, likely due to the difficulty in accessing it with the vacuum hose.

RECOMMENDED ACTION: Inspect the overall tank condition biannually and repair components as needed.

OWS 15, Photo 37

CA-Manhole Access

OWS 15, Photo 38

CA-W-Sediment

OWS 15, Photo 39

CA-W-Top of Outlet Baffle

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 24

OWS 17

OWS 17 was cleaned and inspected on 04/28/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. No water or sediment remained in the structure during the inspection. The tank is a concrete, rectangular structure with a length of 16 feet, a width of 8 feet, and a height of 8 feet 1 inch. The outlet pipe is missing an elbow, and both pipes are rusted and severely deteriorated. The outgoing pipe also has a void and a crack in the wall below the pipe that should be further inspected. Without an elbow installed, this box is functioning as a storage basin rather than an OWS. The overall condition of the OWS is poor; the pipes should be replaced, and an elbow should be installed on the outgoing pipe.

RECOMMENDED ACTION: Inspect overall tank condition annually, replace deteriorated pipes, and add an elbow to the outlet pipe.

OWS 17, Photo 40

CA-NW-Outgoing Pipe

OWS 17, Photo 41

CA-NW-Outgoing Pipe

OWS 17, Photo 42

CA-SE-Incoming Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 25

OWS 26

OWS 26 was cleaned and inspected on 04/28/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. No water remained in the structure during the inspection. The tank is made of steel, cylindrical in shape, and measures 24 feet 1 inch in length, 9 feet 10 inches in width, and 9 feet 10 inches in height. A minor amount of sludge remained in the tank next to the filters. The filters obstruct the outlet pipe; therefore, the outlet pipe could not be visually inspected. OWS 26 is a non-typical separator with vertical walls and filters.

Overall, the OWS appears to be in fair condition. The filters are most likely 18 years old and are potentially at end of life. Manufacturer’s recommendations should be checked for the lifespan of their filters.

RECOMMENDED ACTION: Inspect the overall tank condition annually, replace filters, and monitor the accumulation of filter media debris.

OWS 26, Photo 43

CA-Top View

OWS 26, Photo 44

CA-S_Outlet Filters

OWS 26, Photo 45

CA-Outlet Filter

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 26

OWS 27 – Not Assessed in 2025

OWS 27 was cleaned and inspected on 10/26/2021.

Champion pumped the water out and cleaned the structure, allowing Wolpert to perform the inspection. Confined space entry could not be performed due to obstructions in both manhole access points. The inspection was performed, and pictures of the interior of the OWS were obtained utilizing a pole camera. The tank is a concrete, rectangular structure with a length of 7 feet 6 inches, a width of 5 feet 6 inches, and a height of 5 feet. The permanent pool in the OWS is approximately 48 inches deep. During the inspection, the water depth in the OWS was 1 inch, and the sediment depth was 3 inches. Neither of the inlet pipes had elbows to direct the inflow to the bottom of the tank, and the outlet pipe had a T-fitting instead of just a 90-degree elbow. Based on the CAD drawings provided by CVG, OWS 27 has the highest probability of going into the sanitary system. The drawings show the tank in yellow, being connected to the yellow sanitary system. The overall condition of the OWS was good.

RECOMMENDED ACTION: Inspect overall tank condition biannually and install an elbow pipe on the inlet pipe to divert flows to the bottom of the tank.

OWS 27, Photo 46

CA-SW Sediment

OWS 27, Photo 47

CA-W-MH-Outlet Pipe and Additional Incoming

OWS 27, Photo 48

CA-SE-Sediment

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 27

OWS 29 - Not Assessed in 2025

OWS 29 was cleaned and inspected on 10/27/2021.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. No water or sediment was present during the inspection. Confined space entry could not be performed due to obstructions or manhole access points being too small for entry. The inspection was performed, and pictures of the interior of the OWS were obtained utilizing a pole camera. The tank is a concrete, rectangular structure with a length of 7 feet

10 inches, a width of 4 feet 9 inches, and a height of 5 feet. The permanent pool in the OWS was determined to be approximately 12 inches deep based on the outgoing pipe on the north wall of the tank. There are two 4-inch pipes on the north wall of the tank. It appears that the lower of the two, which is about 12 inches from the bottom of the tank, is the active outlet pipe. The pipe closer to the top of the tank appears to be plugged or severely clogged. The outlet pipe also appears to be clogged with sludge. Both the inlet and outlet pipes have no elbows. The overall condition of the interior of the OWS is good, but the outgoing pipe needs to be maintained and cleared of sludge. The exterior of the top slab is beginning to crack around the north manhole and should be monitored for future maintenance.

RECOMMENDED ACTION: It is recommended to perform deep cleaning of all inlet and outlet pipes to remove debris and repair the exterior slab to prevent further cracking.

OWS 29, Photo 49

CA-N-Opening that Appears Plugged

OWS 29, Photo 50

CA-North side of Tank Cracking

OWS 29, Photo 51

CA-N-Clogged Outlet Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 28

OWS 32

OWS 32 was cleaned and inspected on 04/30/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to perform the inspection. Confined space entry was not needed due to the small size of the OWS, and all pipes were visible from the top of the manhole. The tank is a concrete, circular structure with a diameter of 4 feet and a height of 6 feet. The permanent pool in the OWS is approximately 36 inches deep. Neither the inlet nor outlet pipes had elbows, and further investigation into the plans is needed to understand how this OWS functions.

RECOMMENDED ACTION: Inspect the overall tank condition biannually and investigate plans to determine how this OWS is intended to function.

OWS 32, Photo 46

Location

OWS 32, Photo 47

CA-NW-Inlet Pipe

OWS 32, Photo 48

CA-E-Outlet Pipe

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 29

OWS 33

OWS 33 was cleaned and inspected on 05/01/2025.

Champion pumped the water out and cleaned the structure, allowing Woolpert to safely perform confined space entry into the structure. No water or sediment was present during the inspection. The inspection was performed, and pictures of the interior and exterior of the OWS were obtained. The tank is made of steel, cylindrical in shape, and measures 20 feet in length, 8 feet in width, and 8 feet in height.

The permanent pool in the OWS was undetermined.

Both inlet and outlet pipes are 8-inch iron pipes and appear to be functioning as they should. This is a very complex OWS, containing coalescing plates, a trough, a ball valve, and a baffle. Everything appeared to be in good condition and functioning as designed. The overall condition of the OWS's interior appeared to be in good condition. Although there are signs of rust and corrosion due to the structure being made of steel, everything remains solid, intact, and not rusted through.

RECOMMENDED ACTION: Inspect overall tank condition biannually and repair components as needed.

OWS 33, Photo 49

CB-SE-Coalescing Plates

OWS 33, Photo 50

CC-S-Full View of Outlet Chamber

OWS 33, Photo 51

CC-S-Outgoing Ball Valve

KCAB | CVG OWS CONDITION ASSESSMENT REFRESH | JUNE 2025 DRAFT 30

APPENDIX B –Rough Order of Magnitude (Rom)

Cost Estimate

Oil Water Separator Assessment Rough Order-of-Magnitude Estimate

Report Date:

February 3, 2025

Revision Date:

Revision Date

Revision No.:

Revision No.

Cincinnati/Northern Kentucky International Airport

Hebron, KY

Prepared for:

Woolpert One Easton Oval, Suite 400 Columbus, OH 43219

2594 N. Mount Juliet Road Mount Juliet, TN 37122

(615) 994-1980

February 3, 2025

Jill Geboy Woolpert One Easton Oval, Suite 400 Columbus, OH 43219

RE: Oil Water Separator Assessment Cincinnati/Northern Kentucky International Airport Hebron, KY Rough Order-of-Magnitude Estimate

Dear Jill:

We are pleased to present the Rough Order-of-Magnitude Estimate for the referenced project. The Estimate has been drawn from the information noted in Exhibit A.

Included within the report are our Estimate Notes, which outline the criteria and allowances that were used to produce the estimate.

We appreciate the opportunity to work with you on this project. Should you have any questions or need additional information, please contact us at your convenience.

Sincerely, The Connico Team

Michael Feeney, PE Cost Specialist mgfeeney@connico.com

Connico File No. 6282.25.02

Section 1 Introduction

Task Outline

Project Description

Market Information

Section 2 Estimate Notes

Section 3 Estimate Summary

Recommended Action Estimates

OWS Tank Replacement Estimates

Section 4 Exhibits

A - Document List

B - Quality Control Exhibit

Table of Contents

Connico

6282.25.02 CVG OWS Assessment

Cincinnati/Northern Kentucky

International Airport February 3, 2025

INTRODUCTION

TASK OUTLINE

Woolpert retained Connico as cost consultants to provide an estimate of probable cost for the Oil

Water Separator Assessment project at Cincinnati/Northern Kentucky International Airport in Hebron, KY. The estimate was based on plans, specifications, and other information, as noted in Exhibit A of this report.

In providing estimates of probable construction cost, the client understands that Connico has no control over the cost or availability of labor, equipment, or materials, or over market conditions or the contractor's method of pricing, and that Connico’s estimates of probable construction costs are made based on Connico’s professional judgment and experience. Connico makes no warranty, express or implied, that the bids or the negotiated cost of the work will not vary from Connico’s estimate of probable construction cost.

The estimate of probable cost has been prepared based on information prepared/provided by others. Connico has not verified the accuracy and/or completeness of this information and shall not be responsible for any errors or omissions that may be incorporated because of erroneous information provided by others.

PROJECT DESCRIPTION

The project includes the replacement or repairs of 15 oil water separators at the Cincinnati / Northern Kentucky International Airport.

MARKET INFORMATION

The United States commercial construction market has shown continued growth through increasing construction starts, employment rate, and overall construction spending. This recuperation has been hindered by current economic uncertainties and lasting construction inflation. On the occasion that construction cost inflation is not curbed, overall production in construction may not continue.

Additionally, as project solicitations and contractor backlog increases, contractors will have the opportunity to increase bid rates or become more selective in the projects they pursue.

Construction projects continue to experience significant shortages of skilled labor, supply chain disruptions, and increases in basic construction material prices. It does not appear that these factors will be alleviated in the near term when coupled with recent inflationary pressures and the current global political climate. Consequently, the culmination of all these factors has resulted in both bid day pricing inconsistencies as well as adding uncertainty to construction schedules.

The estimate attempts to incorporate known impacts due to market conditions, material pricing and labor impacts existing in the current market. However, the estimate cannot, and does not, reflect all potential economic impacts that may affect the construction market or the cost of the work. The

International Airport February 3, 2025 impacts on material and labor availability have not been fully realized. The bidding and construction environment is in active flux as we continue to face uncertainty. Construction costs or durations may be impacted by any of these conditions.

International Airport February 3, 2025

ESTIMATE NOTES

GENERAL

Connico did not perform a site observation in preparing this estimate.

MARKUPS AND SOFT COSTS

The following “direct” markups on the cost of work are included in the estimate, based on traditional design, bid, build:

General Contractor Markups

Project Logistics / Phasing & Labor Factor 0.0% General Requirements & Temporary…