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Home My Public Portal AboutP001174322_3/8/2024 2:57:50 PMPost-Construction Stormwater BMP Inspection and Maintenance Record Monsanto Equip #:266289 MSD P Number:P001174322 Project:Bayer 1C Roadway 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:November 9, 2015 Phone:(314) 229-8334 Record Start Date:February 23, 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) 1 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) 1 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) 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 2016.02.23 Initial Inspection 2023.03.08 Inspection 2016.06.02 2023.06.07 Inspection 2016.06.03 2023.09.20 Inspection 2016.06 Removed sediment from surface of biodetention basin 2023.12.06 Inspection 2016.06.20 Inspection 2016.09.14 Inspection 2016.12.06 Inspection 2017.03.02 Inspection 2017.06.19 Inspection 2017.09.13 Inspection 2017.12.12 Inspection 2018.02.07 Maintenance HDS Unit 2018.03.06 Inspection 2018.06.21 Inspection 2018.09.10 Inspection 2018.12.11 Inspection 2019.03.11 Inspection 2019.06.13 Inspection 2019.09.17 Inspection 2019.12.11 Inspection 2020.01.22 Maintenance HDS Unit 2020.03.05 Inspection 2020.06.23 Inspection 2020.08.27 Camera Inspection of Pipes 2020.09.16 Inspection 2020.10.28 Maintenance - Installation of Flexstorm Filter Inserts 2020.12.08 Inspection 2021.03.16 Inspection 2021.06.08 Inspection 2021.09.08 Inspection 2021.12.07 Inspection 2022.03.02 Inspection 2022.06.22 Inspection 2022.09.22 Inspection 2022.10.18 Maintenance Clean HDS Unit 2022.12.07 Inspection Replaced internal components of hydrodynamic separator (HDS) 2 Replaced internal components of hydrodynamic separator (HDS) Post-Construction Stormwater BMP Inspection Report Bayer Equip #:266289 MSD P Number:P001174322 Project:Bayer 1C Roadway Address:700 Chesterfield Parkway West 63017 Inspection Date:December 6, 2023 Time:9:30 AM Weather:39°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 20, 2023 Biodetention Basin (GIS-BMP-7074) Biodetention Basin (GIS-BMP-7074) All Grate Inlets with Side Intakes Action Items Identified During This Inspection: No new action items identified during this inspection. Page 1 REMOVE sediment & debris from all FlexStorm inlet filters (Bayer) --- COMPLETED / ONGOING This report covers the Access Road 1C Roadway Stormwater Treatment System which includes a Hydro International Downstream Defender Hydrodynamic Separator, biodetention basin, as well as associated private inlets, manholes, and piping. The initial inspection of this system on February 23, 2016 revealed that the internal components of the HDS were damaged not functioning, and the biodetention basin had therefore become covered with a layer of silt and sediment up to 1" thick. Replacement of the HDS components was completed on June 2-6, 2016. The clogged filter media was removed from all but the south part of the biodetention basin in the spring of 2016, and the basin was replanted according to the landscaping schedule in the drawings. Unwanted plant growth and dead plant material continue to be managed at prescribed intervals. The HDS unit had experienced a higher than average rate of sediment-loading since inspections began until the addition of FlexStorm filter inserts to the 14 grate inlet structures draining to the system. HDS maintenance was done in February 2018, January 2020, and October 2022. Since the addition of the filter inserts in October 2020 and their routine maintenance, the sediment accumulation in the HDS unit has greatly slowed by 2.5 times the rate of accumulation prior to October 2020. After carefully reviewing each component of the system, I am pleased to report: Based on what was observed, this stormwater treatment system appears to be functioning in accordance with its design intent. Inspector's Summary: Status of Open Action Items Identified During This Reporting Year: Customer: Contact: Phone Number: Email: 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. CONTROL for growth of invasive weeds (Bayer) --- COMPLETED CUT AND REMOVE dead plant material before next growing season (Bayer) --- COMPLETED Post-Construction Stormwater BMP Inspection Report Field Observations: Bypass Structure - ST 3 Attribute Assessment Comments Green Green Downstream Defender Hydrodynamic Separator in ST 12 (GIS-BMP-7068) Assessment Comments Green Green Green Green Green Green Green Green Green Green Biodetention Basin (GIS-BMP-7074) Assessment Comments Green Green Green Green Green Green Green Green Green Green Green Green Green Green Green Private Inlets/Manholes/Piping Assessment Comments Green Yellow Green Green Miscellaneous Assessment Comments Green Green Green Green N/A Photographs See attached sheet(s) Inspector's Notes Bayer Access Roadway 1C - December 6, 2023 Page 2 Trash/debris/leaves - Grate Inlets w/ Side Intakes Water ponding on surface No ponding water March 8, 2023: The HDS unit added 2 inches of sediment and debris since December's inspection. The inspection of the biodetention basin occurred during a rain event. Stormwater was draining into the basin from the HDS unit. Ponding water was noted in the scoured area below the inlet and at the low spot at the middle 25 - 30% of the basin at the low spot around ST 24. Although no underdrain discharge was observed during the inspections, previous visits have shown the basins draining within 48 hours of 1" rain events. June 7, 2023: The HDS unit added 4 inches of sediment and debris since March's inspection. The biodetention basin retains excellent coverage of native vegetation, but invasive weeds (especially the hemp dogbane) need to be managed frequently during the growing season. September 20, 2023: Some weedy growth previously noted was removed but a lot of invasive growth (especially smartweed) still remains. Material in the HDS unit decreased by 3.5 inches. December 6, 2023: All vegetation in the biodetention basin was cleared out for the winter. An increase of 3 inches in the HDS unit puts it at 25% of capacity. Flexstorm filter inserts are full of leaves; maintenance should be done prior to the March inspection. Clear of obstructions; Crack at bottom of ST 23, photo 11 Condition of filter media Filter media is in good condition overall, photos 6 & 7; Heavy clay in profile at south end No indications of clogging Attribute Complaints Not aware of any complaints Mosquitoes Encroachment(s) on facility or easement Weedy growth was removed during the growing season Erosion Other (describe) Sediment Surface of majority of basin appears very porous, photo 6; clay on surface at south end Mulch No mulch remaining on surface of basin Structural components Public Hazard(s) Scouring of surface in middle of basin extends back to ST 24, photo 10 No trash, debris or leaves - winter cleanout was done for the year, photo 3 Weeds Distance from rim to bottom = MONITOR for minor erosion at west end of rock blanket, photo 5 Access Sheen on water surface No sheen Odor No odor Structural components In good condition Clogging Attribute Structural components Pipe inlets and outlets no longer visible after installation of FlexStorm filters Trash/debris/sediment Maintenance due when 75% of Max. depth is exceeded Erosion around structures None System discharge Attribute Access FlexStorm inlet filters continue to collect leaves and debris, photo 1 Distance from rim to sediment =13'-1.5" HDS unit was last maintained in October 2022 Attribute Access Trash/debris/leaves Turf Turf on embankments is in good condition, photo 8 Plants Excellent coverage of native plants; all vegetation was cut down and removed, photo 4 Underdrain No trash, debris or leaves Trash/debris/leaves 2'-6" HDS unit is at 25% of capacity, photo 2 13'-9" Depth of sediment = Max. depth recommended by manufacturer = Sheen on water surface N/A Erosion Cleanouts are clear; No discharge noted from underdrains, photo 12 REMOVE sediment & debris from all FlexStorm inlet filters, photo 1 (Bayer) 0'-7.5" Increase of 3" of sediment since September 2023 inspection Maintenance is not needed according to O & M Manual BAYER – 1C Roadway Stormwater BMP Photos December 6, 2023 1. REMOVE SEDIMENT & DEBRIS FROM ALL FLEXSTORM INLET FILTERS 2. HDS UNIT IS AT 25% CAPACITY (GIS-BMP- 7068) 3. VIEW OF BIODETENTION BASIN (GIS- BMP-7074) 4.ALL VEGETATION WAS CUT DOWN AND REMOVED 5. MONITOR FOR MINOR EROSION AT WEST EDGE OF ROCK BLANKET 6. MULTIPLE PROBES SHOW FILTER MEDIA TO BE IN GOOD CONDITION 7. HIGHER CLAY AND SILT CONTENT ON SURFACE AT SOUTH END OF BASIN 8.TURF ON EMBANKMENTS IS IN GOOD CONDITION 9. UNDERDRAIN IS CLEAR OF OBSTRUCTIONS AND DRY 10. SCOURING OF SURFACE IN MIDDLE OF BASIN 11. CRACK NOTED IN BOTTOM OF NYLOPLAST DRAIN ST 23 12. NYLOPLAST DRAIN ST 24 SHOWS BASIN DISCHARGE IS CLEAR Post-Construction Stormwater BMP Inspection and Maintenance Record Monsanto Equip #:266289 MSD P Number:P001174322 Project:Bayer 1C Roadway 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:November 9, 2015 Phone:(314) 229-8334 Record Start Date:February 23, 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) 1 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) 1 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) 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 2016.02.23 Initial Inspection 2023.03.08 Inspection 2016.06.02 2023.06.07 Inspection 2016.06.03 2023.09.20 Inspection 2016.06 Removed sediment from surface of biodetention basin 2023.12.06 Inspection 2016.06.20 Inspection 2016.09.14 Inspection 2016.12.06 Inspection 2017.03.02 Inspection 2017.06.19 Inspection 2017.09.13 Inspection 2017.12.12 Inspection 2018.02.07 Maintenance HDS Unit 2018.03.06 Inspection 2018.06.21 Inspection 2018.09.10 Inspection 2018.12.11 Inspection 2019.03.11 Inspection 2019.06.13 Inspection 2019.09.17 Inspection 2019.12.11 Inspection 2020.01.22 Maintenance HDS Unit 2020.03.05 Inspection 2020.06.23 Inspection 2020.08.27 Camera Inspection of Pipes 2020.09.16 Inspection 2020.10.28 Maintenance - Installation of Flexstorm Filter Inserts 2020.12.08 Inspection 2021.03.16 Inspection 2021.06.08 Inspection 2021.09.08 Inspection 2021.12.07 Inspection 2022.03.02 Inspection 2022.06.22 Inspection 2022.09.22 Inspection 2022.10.18 Maintenance Clean HDS Unit 2022.12.07 Inspection Replaced internal components of hydrodynamic separator (HDS) 2 Replaced internal components of hydrodynamic separator (HDS) Post-Construction Stormwater BMP Inspection Report Bayer Equip #:266289 MSD P Number:P001174322 Project:Bayer 1C Roadway Address:700 Chesterfield Parkway West 63017 Inspection Date:December 6, 2023 Time:9:30 AM Weather:39°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 20, 2023 Biodetention Basin (GIS-BMP-7074) Biodetention Basin (GIS-BMP-7074) All Grate Inlets with Side Intakes Action Items Identified During This Inspection: No new action items identified during this inspection. Page 1 REMOVE sediment & debris from all FlexStorm inlet filters (Bayer) --- COMPLETED / ONGOING This report covers the Access Road 1C Roadway Stormwater Treatment System which includes a Hydro International Downstream Defender Hydrodynamic Separator, biodetention basin, as well as associated private inlets, manholes, and piping. The initial inspection of this system on February 23, 2016 revealed that the internal components of the HDS were damaged not functioning, and the biodetention basin had therefore become covered with a layer of silt and sediment up to 1" thick. Replacement of the HDS components was completed on June 2-6, 2016. The clogged filter media was removed from all but the south part of the biodetention basin in the spring of 2016, and the basin was replanted according to the landscaping schedule in the drawings. Unwanted plant growth and dead plant material continue to be managed at prescribed intervals. The HDS unit had experienced a higher than average rate of sediment-loading since inspections began until the addition of FlexStorm filter inserts to the 14 grate inlet structures draining to the system. HDS maintenance was done in February 2018, January 2020, and October 2022. Since the addition of the filter inserts in October 2020 and their routine maintenance, the sediment accumulation in the HDS unit has greatly slowed by 2.5 times the rate of accumulation prior to October 2020. After carefully reviewing each component of the system, I am pleased to report: Based on what was observed, this stormwater treatment system appears to be functioning in accordance with its design intent. Inspector's Summary: Status of Open Action Items Identified During This Reporting Year: Customer: Contact: Phone Number: Email: 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. CONTROL for growth of invasive weeds (Bayer) --- COMPLETED CUT AND REMOVE dead plant material before next growing season (Bayer) --- COMPLETED Post-Construction Stormwater BMP Inspection Report Field Observations: Bypass Structure - ST 3 Attribute Assessment Comments Green Green Downstream Defender Hydrodynamic Separator in ST 12 (GIS-BMP-7068) Assessment Comments Green Green Green Green Green Green Green Green Green Green Biodetention Basin (GIS-BMP-7074) Assessment Comments Green Green Green Green Green Green Green Green Green Green Green Green Green Green Green Private Inlets/Manholes/Piping Assessment Comments Green Yellow Green Green Miscellaneous Assessment Comments Green Green Green Green N/A Photographs See attached sheet(s) Inspector's Notes Bayer Access Roadway 1C - December 6, 2023 Page 2 Trash/debris/leaves - Grate Inlets w/ Side Intakes Water ponding on surface No ponding water March 8, 2023: The HDS unit added 2 inches of sediment and debris since December's inspection. The inspection of the biodetention basin occurred during a rain event. Stormwater was draining into the basin from the HDS unit. Ponding water was noted in the scoured area below the inlet and at the low spot at the middle 25 - 30% of the basin at the low spot around ST 24. Although no underdrain discharge was observed during the inspections, previous visits have shown the basins draining within 48 hours of 1" rain events. June 7, 2023: The HDS unit added 4 inches of sediment and debris since March's inspection. The biodetention basin retains excellent coverage of native vegetation, but invasive weeds (especially the hemp dogbane) need to be managed frequently during the growing season. September 20, 2023: Some weedy growth previously noted was removed but a lot of invasive growth (especially smartweed) still remains. Material in the HDS unit decreased by 3.5 inches. December 6, 2023: All vegetation in the biodetention basin was cleared out for the winter. An increase of 3 inches in the HDS unit puts it at 25% of capacity. Flexstorm filter inserts are full of leaves; maintenance should be done prior to the March inspection. Clear of obstructions; Crack at bottom of ST 23, photo 11 Condition of filter media Filter media is in good condition overall, photos 6 & 7; Heavy clay in profile at south end No indications of clogging Attribute Complaints Not aware of any complaints Mosquitoes Encroachment(s) on facility or easement Weedy growth was removed during the growing season Erosion Other (describe) Sediment Surface of majority of basin appears very porous, photo 6; clay on surface at south end Mulch No mulch remaining on surface of basin Structural components Public Hazard(s) Scouring of surface in middle of basin extends back to ST 24, photo 10 No trash, debris or leaves - winter cleanout was done for the year, photo 3 Weeds Distance from rim to bottom = MONITOR for minor erosion at west end of rock blanket, photo 5 Access Sheen on water surface No sheen Odor No odor Structural components In good condition Clogging Attribute Structural components Pipe inlets and outlets no longer visible after installation of FlexStorm filters Trash/debris/sediment Maintenance due when 75% of Max. depth is exceeded Erosion around structures None System discharge Attribute Access FlexStorm inlet filters continue to collect leaves and debris, photo 1 Distance from rim to sediment =13'-1.5" HDS unit was last maintained in October 2022 Attribute Access Trash/debris/leaves Turf Turf on embankments is in good condition, photo 8 Plants Excellent coverage of native plants; all vegetation was cut down and removed, photo 4 Underdrain No trash, debris or leaves Trash/debris/leaves 2'-6" HDS unit is at 25% of capacity, photo 2 13'-9" Depth of sediment = Max. depth recommended by manufacturer = Sheen on water surface N/A Erosion Cleanouts are clear; No discharge noted from underdrains, photo 12 REMOVE sediment & debris from all FlexStorm inlet filters, photo 1 (Bayer) 0'-7.5" Increase of 3" of sediment since September 2023 inspection Maintenance is not needed according to O & M Manual BAYER – 1C Roadway Stormwater BMP Photos December 6, 2023 1. REMOVE SEDIMENT & DEBRIS FROM ALL FLEXSTORM INLET FILTERS 2. HDS UNIT IS AT 25% CAPACITY (GIS-BMP- 7068) 3. VIEW OF BIODETENTION BASIN (GIS- BMP-7074) 4.ALL VEGETATION WAS CUT DOWN AND REMOVED 5. MONITOR FOR MINOR EROSION AT WEST EDGE OF ROCK BLANKET 6. MULTIPLE PROBES SHOW FILTER MEDIA TO BE IN GOOD CONDITION 7. HIGHER CLAY AND SILT CONTENT ON SURFACE AT SOUTH END OF BASIN 8.TURF ON EMBANKMENTS IS IN GOOD CONDITION 9. UNDERDRAIN IS CLEAR OF OBSTRUCTIONS AND DRY 10. SCOURING OF SURFACE IN MIDDLE OF BASIN 11. CRACK NOTED IN BOTTOM OF NYLOPLAST DRAIN ST 23 12. NYLOPLAST DRAIN ST 24 SHOWS BASIN DISCHARGE IS CLEAR