The URL can be used to link to this page

Home My Public Portal AboutP001174324_3/8/2024 3:15:34 PMPost-Construction Stormwater BMP Inspection and Maintenance Record Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Customer:Bayer Contact:Anna Tang Phone Number:314-694-3169 Email:anna.tang@bayer.com Inspector(s):Marianne Pott Company:Stormwater STL LLC Address:6514 Lansdowne Avenue 63109 Constr. Approval:February 23, 2016 Phone:(314) 229-8334 Record Start Date:June 20, 2016 E-mail:marianne@stormwater-stl.net Stormwater Treatment Facilities:Total Count: Count Type Description Count Type Description BIOR BIORETENTION/RAINGARDEN (A)P-1 MICROPOOL EXTENDED DETENTION POND (A) BIOS BIORETENTION/RAINGARDEN (SMALL) (A)P-2 WET POND (A) GRWD GRAVEL WETLAND (A)P-3 WET EXTENDED DETENTION POND (A) CIST CISTERN/DRYWELL (U)P-5 POCKET POND (A) O-1 DRY SWALE - LARGE (A)W-2 ED SHALLOW WETLAND (A) O-2 DRY SWALE - SMALL (A)W-3 POND/WETLAND SYSTEM (A) O-3 WET SWALE - LARGE (A)SCDN STORM CREDIT - DISCONNECT NONROOFTOP (A) O-4 WET SWALE - SMALL (A)SCDR STORM CREDIT - DISCONNECT ROOFTOP (A) HDSP PROPRIETARY HYDRODYNAMIC SEPARATOR SCES STORM CREDIT - ENVIRONMENTALLY SENSTV(A) I-1 INFILTRATION TRENCH (A)SCNA STORM CREDIT - NATURAL AREA CONSERVA (A) I-2 INFILTRATION BASIN (A)SCOC STORM CREDIT - OPEN CHANNEL USE (A) AMDS AMENDED SOILS (A)SCSB STORM CREDIT - SHEET FLOW TO BUFFER (A) GRRF GREEN ROOF (A)F-1 SURFACE SAND FILTER (A) O-5 FILTER STRIPS - LARGE (A)F-3 PERIMETER SAND FILTER (A) O-6 FILTER STRIPS - SMALL (A)F-4 ORGANIC FILTER (A) 3 PPAS PERMEABLE PAVEMENT - ASPHALT (A)F-5 POCKET SAND FILTER (A) PPBK PERMEABLE PAVEMENT - PAVER BLOCK (A)F-PR PROPRIETARY BMP FILTER (U) PPCO PERMEABLE PAVEMENT - CONCRETE (A)F-2 UNDERGROUND SAND FILTER (U) PPGR PERMEABLE PAVEMENT - GRAVEL (A) DET DETENTION WQS UNDERGROUND WATER QUALITY STORAGE DET U UNDERGROUND FBAY PRETREATMENT FOREBAY Inspection, Maintenance and Annual Report Submission Record: Date Activity Date Activity 2016.06.20 Initial Inspection 2016.09.14 Inspection 2016.12.06 Inspection 2017.02.22 Vacuumed porous asphalt pavement 2017.03.02 Inspection 2017.06.19 Inspection 2017.09.13 Inspection 2017.12.12 Inspection 2018.03.07 Inspection 2018.06.22 Inspection 2018.09.11 Inspection 2018.12.12 Inspection 2019.03.12 Inspection 2019.06.14 Inspection 2019.09.18 Inspection 2019.12.12 Inspection 2020.03.06 Inspection 2020.06.24 Inspection 2020.09.17 Inspection 2020.12.08 Inspection 2021.03.16 Inspection 2021.06.09 Inspection 2021.09.09 Inspection 2021.12.07 Inspection 2022.03.02 Inspection 2022.06.15 Inspection 2022.09.21 Inspection 2022.12.09 Inspection 2023.03.08 Inspection 2023.06.08 Inspection 2023.09.21 Inspection 2023.12.07 Inspection 3 Post-Construction Stormwater BMP Inspection Report Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Inspection Date:December 7, 2023 Time:7:00 AM Weather:42°F; Sunny Last rain event:0.01" on December 5, 2023 Last one inch rainfall:1.62" on September 27, 2023 Bayer Inspector(s):Marianne Pott Anna Tang Company:Stormwater STL LLC 314-694-3169 Address:6514 Lansdowne Avenue 63109 anna.tang@bayer.com Phone:(314) 229-8334 E-mail:marianne@stormwater-stl.net Last Inspection Date:September 21, 2023 Inspector's Summary: Status of Open Action Items Identified During This Reporting Year: North Area of Porous Asphalt Pavement (GIS-BMP-7148) East Area of Porous Asphalt Pavement (GIS-BMP-7188) Action Items Identified During This Inspection: No new action items were identified during this inspection. Page 1 REMOVE sediment, leaves and debris along north edge (Bayer) --- NOT COMPLETED Construction was approved by MSD in February 2016 and includes 54 parking spaces of porous asphalt pavement and associated inlets, manholes and piping. The pavement has previously been used for storage of construction equipment and materials, which resulted in a minor amount of damage to the surface of the porous asphalt. Porous surfaces are vacuumed periodically to remove sediment, debris and loosened aggregate. Silt fencing has been used along the northern edge to prevent the migration of silt onto the north porous surface. The east porous surface is adjacent to an unpaved storage lot and therefore experiences higher rates of sedimentation. Simultaneously pressure washing and vacuuming, as can only be done with a commercial vacuum truck, may be needed to rehabilitate the east installation and parts of the north installation impacted by silt, excessive sediment and mulch. With the continued use of the adjacent area for storage of landscaping materials, it is not practical for that sort of treatment. Until then, the east surface will be swept up periodically. Therefore, after a careful review of each component of the system, I am pleased to report: Based on what was observed, this stormwater treatment facility appears to be functioning in accordance with the design intent. This document has been prepared exclusively for the Customer noted above (Customer) by Stormwater STL LLC (Stormwater STL), based on a visual inspection conducted on the date(s) noted above. Unless specifically indicated, Stormwater STL did not undertake any forensic investigation at this location on the date(s) noted. The opinions expressed in this document relate only to the condition of the site and the Post-Construction Stormwater BMP(s) as observed by Stormwater STL on the date(s) noted. The content of this document reflects the opinion of Stormwater STL only and Stormwater STL makes no express or implied representation or warranty with respect to the conditions described or the functionality of the systems identified in this report. Other than Customer, third parties who rely upon this document do so solely at their own risk and Stormwater STL disclaims all liability, damages or loss with respect to such reliance. Neither Customer nor Stormwater STL, nor any person acting for and/or on behalf of those companies, assumes any responsibility, duty of care or liability to any person to update the contents of this document or to distribute any subsequently learned information to recipients of this document other than to Customer. This disclaimer must accompany every copy of this document, which is an integral document and must be read in its entirety. Customer: Contact: Phone Number: Email: CLEAN surface to remove excessive sediment and mulch debris (Bayer) --- NOT COMPLETED Post-Construction Stormwater BMP Inspection Report Field Observations: North Porous Asphalt Pavement (GIS-BMP-7148) Assessment Comments Yellow Sediment Green Green Green East Porous Asphalt Pavement (GIS-BMP-7188) Assessment Comments Yellow Sediment Green Green Green South Porous Asphalt Pavement (GIS-BMP-7189) Assessment Comments Green Sediment Green Green Green Private Inlets/Manholes/Piping Assessment Comments Green Green Green Green Miscellaneous Assessment Comments Green Green Green Green Green Photographs See attached sheet(s) Inspector's Notes Bayer Temporary Parking Addition - December 7, 2023 Page 2 Other (describe) No settlement, potholes or cracking; some damage to surface from storage of materials REMOVE sediment, leaves and debris along north edge, photo 5 (Bayer) Attribute Clogging of pavement pores Trash/debris/leaves Erosion/settlement around structures MONITOR for further erosion along north edge System discharge Settlement/potholes/cracking Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Clear, photo 9 Attribute Clogging of pavement pores No indications of clogging Surface is very porous; gravel has collected at southwest end from snow plowing Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Attribute Most of surface is very porous; silt, leaves and debris collecting along north edge Surface spalling Seam is intact; some surface deterioration noted at east end Access IMPORTANT NOTE ABOUT MAINTAINING POROUS PAVEMENTS It's important for owners and property managers to understand that there is currently no proven way to rehabilitate pervious asphalt or concrete pavement that becomes clogged. The only option for clogged pervious pavement is total removal and replacement. The pervious asphalt or concrete on this project should therefore be vacuumed at least twice each year - in the early spring and late fall. Avoid using sweepers (i.e. vacuums with brushes), pressure washers and blowers that may force surface grit deeper into pavement pores. Rock salt, sand and other similar de-icing materials may also damage or clog these pavements. If you have questions about pervious pavement or would like to develop a maintenance program that protects your pavement assets, please let me know. December 7, 2021: The north and south surfaces remain in good condition but sediment and gravel continue to build on the east area. March 2, 2022: The east end of the north porous area was used to store dirt, and some the pore spaces are filled with silt and clay particles. Silt also continues to build on the east porous area. These areas should be simultaneously vacuumed and pressure washed by a vacuum truck to restore porosity to the pavements. Leaves and debris should also be cleaned up along the north edge of the north area. June 15, 2022: No changes noted. September 21, 2022: Heavy sediment and mulch debris were blown off of the porous surfaces at the east area and the east end of the north area. December 9, 2022: The north edge and the east area of the porous asphalt surfaces should be cleaned off as much as possible. March 8, 2023: Inspection was conducted during a steady light rain. Some water was starting to collect in the pore spaces at the east surface. Underdrain discharge was noted at the end of the pipe. June 8, 2023: No changes noted. September 21, 2023: No changes noted. December 7, 2023: No changes noted. Attribute Clogging of pavement pores CLEAN surface to remove excessive sediment and mulch debris, photo 7 (Bayer) Sediment & mulch was built up across the north half of the porous surface, photos 2 & 7 Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Mosquitoes Encroachment(s) on facility or easement Public Hazard(s) Attribute Complaints BAYER – Temporary Parking Addn Stormwater BMP Photos December 7, 2023 1. VIEW OF NORTH POROUS SURFACE (GIS- BMP-7148) 2. VIEW OF EAST POROUS SURFACE (GIS- BMP-7188) 3. VIEW OF SOUTH POROUS SURFACE (GIS- BMP-7189) 4. OPEN AND ABUNDANT PORE SPACES ACROSS MAJORITY OF POROUS SURFACES 5. REMOVE SEDIMENT, LEAVES & DEBRIS FROM NORTH EDGE OF POROUS ASPHALT 6. SILT COLLECTING IN PORE SPACES ABOVE CURB STOPS ON NORTH POROUS SURFACE 7. CLEAN EAST SURFACE TO REMOVE EXCESSIVE SEDIMENT AND MULCH DEBRIS 8. OBSERVATION WELLS SHOW STORAGE BEDS OF POROUS SURFACES ARE DRY 9. DISCHARGE NOTED FROM SYSTEM UNDERDRAIN Post-Construction Stormwater BMP Inspection and Maintenance Record Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Customer:Bayer Contact:Anna Tang Phone Number:314-694-3169 Email:anna.tang@bayer.com Inspector(s):Marianne Pott Company:Stormwater STL LLC Address:6514 Lansdowne Avenue 63109 Constr. Approval:February 23, 2016 Phone:(314) 229-8334 Record Start Date:June 20, 2016 E-mail:marianne@stormwater-stl.net Stormwater Treatment Facilities:Total Count: Count Type Description Count Type Description BIOR BIORETENTION/RAINGARDEN (A)P-1 MICROPOOL EXTENDED DETENTION POND (A) BIOS BIORETENTION/RAINGARDEN (SMALL) (A)P-2 WET POND (A) GRWD GRAVEL WETLAND (A)P-3 WET EXTENDED DETENTION POND (A) CIST CISTERN/DRYWELL (U)P-5 POCKET POND (A) O-1 DRY SWALE - LARGE (A)W-2 ED SHALLOW WETLAND (A) O-2 DRY SWALE - SMALL (A)W-3 POND/WETLAND SYSTEM (A) O-3 WET SWALE - LARGE (A)SCDN STORM CREDIT - DISCONNECT NONROOFTOP (A) O-4 WET SWALE - SMALL (A)SCDR STORM CREDIT - DISCONNECT ROOFTOP (A) HDSP PROPRIETARY HYDRODYNAMIC SEPARATOR SCES STORM CREDIT - ENVIRONMENTALLY SENSTV(A) I-1 INFILTRATION TRENCH (A)SCNA STORM CREDIT - NATURAL AREA CONSERVA (A) I-2 INFILTRATION BASIN (A)SCOC STORM CREDIT - OPEN CHANNEL USE (A) AMDS AMENDED SOILS (A)SCSB STORM CREDIT - SHEET FLOW TO BUFFER (A) GRRF GREEN ROOF (A)F-1 SURFACE SAND FILTER (A) O-5 FILTER STRIPS - LARGE (A)F-3 PERIMETER SAND FILTER (A) O-6 FILTER STRIPS - SMALL (A)F-4 ORGANIC FILTER (A) 3 PPAS PERMEABLE PAVEMENT - ASPHALT (A)F-5 POCKET SAND FILTER (A) PPBK PERMEABLE PAVEMENT - PAVER BLOCK (A)F-PR PROPRIETARY BMP FILTER (U) PPCO PERMEABLE PAVEMENT - CONCRETE (A)F-2 UNDERGROUND SAND FILTER (U) PPGR PERMEABLE PAVEMENT - GRAVEL (A) DET DETENTION WQS UNDERGROUND WATER QUALITY STORAGE DET U UNDERGROUND FBAY PRETREATMENT FOREBAY Inspection, Maintenance and Annual Report Submission Record: Date Activity Date Activity 2016.06.20 Initial Inspection 2016.09.14 Inspection 2016.12.06 Inspection 2017.02.22 Vacuumed porous asphalt pavement 2017.03.02 Inspection 2017.06.19 Inspection 2017.09.13 Inspection 2017.12.12 Inspection 2018.03.07 Inspection 2018.06.22 Inspection 2018.09.11 Inspection 2018.12.12 Inspection 2019.03.12 Inspection 2019.06.14 Inspection 2019.09.18 Inspection 2019.12.12 Inspection 2020.03.06 Inspection 2020.06.24 Inspection 2020.09.17 Inspection 2020.12.08 Inspection 2021.03.16 Inspection 2021.06.09 Inspection 2021.09.09 Inspection 2021.12.07 Inspection 2022.03.02 Inspection 2022.06.15 Inspection 2022.09.21 Inspection 2022.12.09 Inspection 2023.03.08 Inspection 2023.06.08 Inspection 2023.09.21 Inspection 2023.12.07 Inspection 3 Post-Construction Stormwater BMP Inspection Report Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Inspection Date:December 7, 2023 Time:7:00 AM Weather:42°F; Sunny Last rain event:0.01" on December 5, 2023 Last one inch rainfall:1.62" on September 27, 2023 Bayer Inspector(s):Marianne Pott Anna Tang Company:Stormwater STL LLC 314-694-3169 Address:6514 Lansdowne Avenue 63109 anna.tang@bayer.com Phone:(314) 229-8334 E-mail:marianne@stormwater-stl.net Last Inspection Date:September 21, 2023 Inspector's Summary: Status of Open Action Items Identified During This Reporting Year: North Area of Porous Asphalt Pavement (GIS-BMP-7148) East Area of Porous Asphalt Pavement (GIS-BMP-7188) Action Items Identified During This Inspection: No new action items were identified during this inspection. Page 1 REMOVE sediment, leaves and debris along north edge (Bayer) --- NOT COMPLETED Construction was approved by MSD in February 2016 and includes 54 parking spaces of porous asphalt pavement and associated inlets, manholes and piping. The pavement has previously been used for storage of construction equipment and materials, which resulted in a minor amount of damage to the surface of the porous asphalt. Porous surfaces are vacuumed periodically to remove sediment, debris and loosened aggregate. Silt fencing has been used along the northern edge to prevent the migration of silt onto the north porous surface. The east porous surface is adjacent to an unpaved storage lot and therefore experiences higher rates of sedimentation. Simultaneously pressure washing and vacuuming, as can only be done with a commercial vacuum truck, may be needed to rehabilitate the east installation and parts of the north installation impacted by silt, excessive sediment and mulch. With the continued use of the adjacent area for storage of landscaping materials, it is not practical for that sort of treatment. Until then, the east surface will be swept up periodically. Therefore, after a careful review of each component of the system, I am pleased to report: Based on what was observed, this stormwater treatment facility appears to be functioning in accordance with the design intent. This document has been prepared exclusively for the Customer noted above (Customer) by Stormwater STL LLC (Stormwater STL), based on a visual inspection conducted on the date(s) noted above. Unless specifically indicated, Stormwater STL did not undertake any forensic investigation at this location on the date(s) noted. The opinions expressed in this document relate only to the condition of the site and the Post-Construction Stormwater BMP(s) as observed by Stormwater STL on the date(s) noted. The content of this document reflects the opinion of Stormwater STL only and Stormwater STL makes no express or implied representation or warranty with respect to the conditions described or the functionality of the systems identified in this report. Other than Customer, third parties who rely upon this document do so solely at their own risk and Stormwater STL disclaims all liability, damages or loss with respect to such reliance. Neither Customer nor Stormwater STL, nor any person acting for and/or on behalf of those companies, assumes any responsibility, duty of care or liability to any person to update the contents of this document or to distribute any subsequently learned information to recipients of this document other than to Customer. This disclaimer must accompany every copy of this document, which is an integral document and must be read in its entirety. Customer: Contact: Phone Number: Email: CLEAN surface to remove excessive sediment and mulch debris (Bayer) --- NOT COMPLETED Post-Construction Stormwater BMP Inspection Report Field Observations: North Porous Asphalt Pavement (GIS-BMP-7148) Assessment Comments Yellow Sediment Green Green Green East Porous Asphalt Pavement (GIS-BMP-7188) Assessment Comments Yellow Sediment Green Green Green South Porous Asphalt Pavement (GIS-BMP-7189) Assessment Comments Green Sediment Green Green Green Private Inlets/Manholes/Piping Assessment Comments Green Green Green Green Miscellaneous Assessment Comments Green Green Green Green Green Photographs See attached sheet(s) Inspector's Notes Bayer Temporary Parking Addition - December 7, 2023 Page 2 Other (describe) No settlement, potholes or cracking; some damage to surface from storage of materials REMOVE sediment, leaves and debris along north edge, photo 5 (Bayer) Attribute Clogging of pavement pores Trash/debris/leaves Erosion/settlement around structures MONITOR for further erosion along north edge System discharge Settlement/potholes/cracking Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Clear, photo 9 Attribute Clogging of pavement pores No indications of clogging Surface is very porous; gravel has collected at southwest end from snow plowing Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Attribute Most of surface is very porous; silt, leaves and debris collecting along north edge Surface spalling Seam is intact; some surface deterioration noted at east end Access IMPORTANT NOTE ABOUT MAINTAINING POROUS PAVEMENTS It's important for owners and property managers to understand that there is currently no proven way to rehabilitate pervious asphalt or concrete pavement that becomes clogged. The only option for clogged pervious pavement is total removal and replacement. The pervious asphalt or concrete on this project should therefore be vacuumed at least twice each year - in the early spring and late fall. Avoid using sweepers (i.e. vacuums with brushes), pressure washers and blowers that may force surface grit deeper into pavement pores. Rock salt, sand and other similar de-icing materials may also damage or clog these pavements. If you have questions about pervious pavement or would like to develop a maintenance program that protects your pavement assets, please let me know. December 7, 2021: The north and south surfaces remain in good condition but sediment and gravel continue to build on the east area. March 2, 2022: The east end of the north porous area was used to store dirt, and some the pore spaces are filled with silt and clay particles. Silt also continues to build on the east porous area. These areas should be simultaneously vacuumed and pressure washed by a vacuum truck to restore porosity to the pavements. Leaves and debris should also be cleaned up along the north edge of the north area. June 15, 2022: No changes noted. September 21, 2022: Heavy sediment and mulch debris were blown off of the porous surfaces at the east area and the east end of the north area. December 9, 2022: The north edge and the east area of the porous asphalt surfaces should be cleaned off as much as possible. March 8, 2023: Inspection was conducted during a steady light rain. Some water was starting to collect in the pore spaces at the east surface. Underdrain discharge was noted at the end of the pipe. June 8, 2023: No changes noted. September 21, 2023: No changes noted. December 7, 2023: No changes noted. Attribute Clogging of pavement pores CLEAN surface to remove excessive sediment and mulch debris, photo 7 (Bayer) Sediment & mulch was built up across the north half of the porous surface, photos 2 & 7 Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Mosquitoes Encroachment(s) on facility or easement Public Hazard(s) Attribute Complaints BAYER – Temporary Parking Addn Stormwater BMP Photos December 7, 2023 1. VIEW OF NORTH POROUS SURFACE (GIS- BMP-7148) 2. VIEW OF EAST POROUS SURFACE (GIS- BMP-7188) 3. VIEW OF SOUTH POROUS SURFACE (GIS- BMP-7189) 4. OPEN AND ABUNDANT PORE SPACES ACROSS MAJORITY OF POROUS SURFACES 5. REMOVE SEDIMENT, LEAVES & DEBRIS FROM NORTH EDGE OF POROUS ASPHALT 6. SILT COLLECTING IN PORE SPACES ABOVE CURB STOPS ON NORTH POROUS SURFACE 7. CLEAN EAST SURFACE TO REMOVE EXCESSIVE SEDIMENT AND MULCH DEBRIS 8. OBSERVATION WELLS SHOW STORAGE BEDS OF POROUS SURFACES ARE DRY 9. DISCHARGE NOTED FROM SYSTEM UNDERDRAIN Post-Construction Stormwater BMP Inspection and Maintenance Record Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Customer:Bayer Contact:Anna Tang Phone Number:314-694-3169 Email:anna.tang@bayer.com Inspector(s):Marianne Pott Company:Stormwater STL LLC Address:6514 Lansdowne Avenue 63109 Constr. Approval:February 23, 2016 Phone:(314) 229-8334 Record Start Date:June 20, 2016 E-mail:marianne@stormwater-stl.net Stormwater Treatment Facilities:Total Count: Count Type Description Count Type Description BIOR BIORETENTION/RAINGARDEN (A)P-1 MICROPOOL EXTENDED DETENTION POND (A) BIOS BIORETENTION/RAINGARDEN (SMALL) (A)P-2 WET POND (A) GRWD GRAVEL WETLAND (A)P-3 WET EXTENDED DETENTION POND (A) CIST CISTERN/DRYWELL (U)P-5 POCKET POND (A) O-1 DRY SWALE - LARGE (A)W-2 ED SHALLOW WETLAND (A) O-2 DRY SWALE - SMALL (A)W-3 POND/WETLAND SYSTEM (A) O-3 WET SWALE - LARGE (A)SCDN STORM CREDIT - DISCONNECT NONROOFTOP (A) O-4 WET SWALE - SMALL (A)SCDR STORM CREDIT - DISCONNECT ROOFTOP (A) HDSP PROPRIETARY HYDRODYNAMIC SEPARATOR SCES STORM CREDIT - ENVIRONMENTALLY SENSTV(A) I-1 INFILTRATION TRENCH (A)SCNA STORM CREDIT - NATURAL AREA CONSERVA (A) I-2 INFILTRATION BASIN (A)SCOC STORM CREDIT - OPEN CHANNEL USE (A) AMDS AMENDED SOILS (A)SCSB STORM CREDIT - SHEET FLOW TO BUFFER (A) GRRF GREEN ROOF (A)F-1 SURFACE SAND FILTER (A) O-5 FILTER STRIPS - LARGE (A)F-3 PERIMETER SAND FILTER (A) O-6 FILTER STRIPS - SMALL (A)F-4 ORGANIC FILTER (A) 3 PPAS PERMEABLE PAVEMENT - ASPHALT (A)F-5 POCKET SAND FILTER (A) PPBK PERMEABLE PAVEMENT - PAVER BLOCK (A)F-PR PROPRIETARY BMP FILTER (U) PPCO PERMEABLE PAVEMENT - CONCRETE (A)F-2 UNDERGROUND SAND FILTER (U) PPGR PERMEABLE PAVEMENT - GRAVEL (A) DET DETENTION WQS UNDERGROUND WATER QUALITY STORAGE DET U UNDERGROUND FBAY PRETREATMENT FOREBAY Inspection, Maintenance and Annual Report Submission Record: Date Activity Date Activity 2016.06.20 Initial Inspection 2016.09.14 Inspection 2016.12.06 Inspection 2017.02.22 Vacuumed porous asphalt pavement 2017.03.02 Inspection 2017.06.19 Inspection 2017.09.13 Inspection 2017.12.12 Inspection 2018.03.07 Inspection 2018.06.22 Inspection 2018.09.11 Inspection 2018.12.12 Inspection 2019.03.12 Inspection 2019.06.14 Inspection 2019.09.18 Inspection 2019.12.12 Inspection 2020.03.06 Inspection 2020.06.24 Inspection 2020.09.17 Inspection 2020.12.08 Inspection 2021.03.16 Inspection 2021.06.09 Inspection 2021.09.09 Inspection 2021.12.07 Inspection 2022.03.02 Inspection 2022.06.15 Inspection 2022.09.21 Inspection 2022.12.09 Inspection 2023.03.08 Inspection 2023.06.08 Inspection 2023.09.21 Inspection 2023.12.07 Inspection 3 Post-Construction Stormwater BMP Inspection Report Bayer Equip #:266287 MSD P Number:P001174324 Project:Bayer Temporary Parking Addition Address:700 Chesterfield Parkway West 63017 Inspection Date:December 7, 2023 Time:7:00 AM Weather:42°F; Sunny Last rain event:0.01" on December 5, 2023 Last one inch rainfall:1.62" on September 27, 2023 Bayer Inspector(s):Marianne Pott Anna Tang Company:Stormwater STL LLC 314-694-3169 Address:6514 Lansdowne Avenue 63109 anna.tang@bayer.com Phone:(314) 229-8334 E-mail:marianne@stormwater-stl.net Last Inspection Date:September 21, 2023 Inspector's Summary: Status of Open Action Items Identified During This Reporting Year: North Area of Porous Asphalt Pavement (GIS-BMP-7148) East Area of Porous Asphalt Pavement (GIS-BMP-7188) Action Items Identified During This Inspection: No new action items were identified during this inspection. Page 1 REMOVE sediment, leaves and debris along north edge (Bayer) --- NOT COMPLETED Construction was approved by MSD in February 2016 and includes 54 parking spaces of porous asphalt pavement and associated inlets, manholes and piping. The pavement has previously been used for storage of construction equipment and materials, which resulted in a minor amount of damage to the surface of the porous asphalt. Porous surfaces are vacuumed periodically to remove sediment, debris and loosened aggregate. Silt fencing has been used along the northern edge to prevent the migration of silt onto the north porous surface. The east porous surface is adjacent to an unpaved storage lot and therefore experiences higher rates of sedimentation. Simultaneously pressure washing and vacuuming, as can only be done with a commercial vacuum truck, may be needed to rehabilitate the east installation and parts of the north installation impacted by silt, excessive sediment and mulch. With the continued use of the adjacent area for storage of landscaping materials, it is not practical for that sort of treatment. Until then, the east surface will be swept up periodically. Therefore, after a careful review of each component of the system, I am pleased to report: Based on what was observed, this stormwater treatment facility appears to be functioning in accordance with the design intent. This document has been prepared exclusively for the Customer noted above (Customer) by Stormwater STL LLC (Stormwater STL), based on a visual inspection conducted on the date(s) noted above. Unless specifically indicated, Stormwater STL did not undertake any forensic investigation at this location on the date(s) noted. The opinions expressed in this document relate only to the condition of the site and the Post-Construction Stormwater BMP(s) as observed by Stormwater STL on the date(s) noted. The content of this document reflects the opinion of Stormwater STL only and Stormwater STL makes no express or implied representation or warranty with respect to the conditions described or the functionality of the systems identified in this report. Other than Customer, third parties who rely upon this document do so solely at their own risk and Stormwater STL disclaims all liability, damages or loss with respect to such reliance. Neither Customer nor Stormwater STL, nor any person acting for and/or on behalf of those companies, assumes any responsibility, duty of care or liability to any person to update the contents of this document or to distribute any subsequently learned information to recipients of this document other than to Customer. This disclaimer must accompany every copy of this document, which is an integral document and must be read in its entirety. Customer: Contact: Phone Number: Email: CLEAN surface to remove excessive sediment and mulch debris (Bayer) --- NOT COMPLETED Post-Construction Stormwater BMP Inspection Report Field Observations: North Porous Asphalt Pavement (GIS-BMP-7148) Assessment Comments Yellow Sediment Green Green Green East Porous Asphalt Pavement (GIS-BMP-7188) Assessment Comments Yellow Sediment Green Green Green South Porous Asphalt Pavement (GIS-BMP-7189) Assessment Comments Green Sediment Green Green Green Private Inlets/Manholes/Piping Assessment Comments Green Green Green Green Miscellaneous Assessment Comments Green Green Green Green Green Photographs See attached sheet(s) Inspector's Notes Bayer Temporary Parking Addition - December 7, 2023 Page 2 Other (describe) No settlement, potholes or cracking; some damage to surface from storage of materials REMOVE sediment, leaves and debris along north edge, photo 5 (Bayer) Attribute Clogging of pavement pores Trash/debris/leaves Erosion/settlement around structures MONITOR for further erosion along north edge System discharge Settlement/potholes/cracking Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Clear, photo 9 Attribute Clogging of pavement pores No indications of clogging Surface is very porous; gravel has collected at southwest end from snow plowing Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Settlement/potholes/cracking No settlement, potholes or cracking; some damage to surface from storage of materials Attribute Most of surface is very porous; silt, leaves and debris collecting along north edge Surface spalling Seam is intact; some surface deterioration noted at east end Access IMPORTANT NOTE ABOUT MAINTAINING POROUS PAVEMENTS It's important for owners and property managers to understand that there is currently no proven way to rehabilitate pervious asphalt or concrete pavement that becomes clogged. The only option for clogged pervious pavement is total removal and replacement. The pervious asphalt or concrete on this project should therefore be vacuumed at least twice each year - in the early spring and late fall. Avoid using sweepers (i.e. vacuums with brushes), pressure washers and blowers that may force surface grit deeper into pavement pores. Rock salt, sand and other similar de-icing materials may also damage or clog these pavements. If you have questions about pervious pavement or would like to develop a maintenance program that protects your pavement assets, please let me know. December 7, 2021: The north and south surfaces remain in good condition but sediment and gravel continue to build on the east area. March 2, 2022: The east end of the north porous area was used to store dirt, and some the pore spaces are filled with silt and clay particles. Silt also continues to build on the east porous area. These areas should be simultaneously vacuumed and pressure washed by a vacuum truck to restore porosity to the pavements. Leaves and debris should also be cleaned up along the north edge of the north area. June 15, 2022: No changes noted. September 21, 2022: Heavy sediment and mulch debris were blown off of the porous surfaces at the east area and the east end of the north area. December 9, 2022: The north edge and the east area of the porous asphalt surfaces should be cleaned off as much as possible. March 8, 2023: Inspection was conducted during a steady light rain. Some water was starting to collect in the pore spaces at the east surface. Underdrain discharge was noted at the end of the pipe. June 8, 2023: No changes noted. September 21, 2023: No changes noted. December 7, 2023: No changes noted. Attribute Clogging of pavement pores CLEAN surface to remove excessive sediment and mulch debris, photo 7 (Bayer) Sediment & mulch was built up across the north half of the porous surface, photos 2 & 7 Surface spalling Seam is intact; very minimal surface deterioration or loosened aggregate noted Mosquitoes Encroachment(s) on facility or easement Public Hazard(s) Attribute Complaints BAYER – Temporary Parking Addn Stormwater BMP Photos December 7, 2023 1. VIEW OF NORTH POROUS SURFACE (GIS- BMP-7148) 2. VIEW OF EAST POROUS SURFACE (GIS- BMP-7188) 3. VIEW OF SOUTH POROUS SURFACE (GIS- BMP-7189) 4. OPEN AND ABUNDANT PORE SPACES ACROSS MAJORITY OF POROUS SURFACES 5. REMOVE SEDIMENT, LEAVES & DEBRIS FROM NORTH EDGE OF POROUS ASPHALT 6. SILT COLLECTING IN PORE SPACES ABOVE CURB STOPS ON NORTH POROUS SURFACE 7. CLEAN EAST SURFACE TO REMOVE EXCESSIVE SEDIMENT AND MULCH DEBRIS 8. OBSERVATION WELLS SHOW STORAGE BEDS OF POROUS SURFACES ARE DRY 9. DISCHARGE NOTED FROM SYSTEM UNDERDRAIN