Document JJodZDwZkgLe236KLjg33840e

CWA COMPLIANCE EVALUATION INSPECTION REPORT U.S. ENVIRONMENTAL PROTECTION AGENCY, REGION 5 Facility: City of Peoria - Combined Sewer System/Consent Decree Oversight Inspection 3505 North Dries Lane, Peoria, Illinois 61604 NPDES Permit Number: IL0037800 Date of Inspection: May 20, 2025 Purpose: To evaluate Peoria's compliance with it 2022 Consent Decree along with other applicable regulations under the National Pollutant Discharge Elimination System (NPDES) permit program and the Clean Water Act (CWA). EPA Region 5 Water Enforcement Compliance Assurance Representatives: Keith Middleton, Environmental Engineer, middleton.keith@epa.gov, 312-886-6465 Bill Jones, Environmental Engineer, jones.william@epa.gov, 312-886-6058 Illinois Environmental Protection Agency Representatives: Shannon Soucie, Inspector, shannon.soucie@illinois.gov, 309-671-3029 Kyle Phelps, Inspector, kyle.phelps@illinois.gov, 312-671-3184 City of Peoria Representatives: Rick Powers, Director of Public Works, rpowers@peoriagov.org, 309-494-8818 Andrea Klopfenster, City Engineer, aklopfenstein@peoriagov.org, 309-494-8800 Paola Mendez-Silvagnoli, Assistant City Engineer, pmendez@peoriagov.org, 309-494-8811 Sie Maroon, Deputy Director- Operations, smaroon@peoriagov.org, 309-494-8885 Sidney Maroon, Engineer Technician Mead & Hunt Representatives: 3 Amy Post, Department Manager, amy.post@meadhunt.com, 414-755-1132 Eric Carlson, Senior Engineer, eric.carlson@meadhunt.com, 309-605-0305 Kyla Dean, Senior Project Engineer, kyla.dean@meadhunt.com, 414-755-1168 Report Prepared by: Keith Middleton, Environmental Engineer Digitally signed by KEITH KEITH MIDDLETON MIDDLETON Inspector Signature: _________________________D_a_te_: 2_0_2_5._07_._03_1_6_:1_0_:2_4_-_05_'0_0_' ______________ Approver Name and Title: Ryan J. Bahr, Section 2 Supervisor, Water Enforcement and Compliance Assurance Branch, U.S. EPA Region 5 Enforcement and Compliance Assurance Division Bahr, Ryan Digitally signed by Bahr, Ryan Date: 2025.07.03 16:15:17 -05'00' Approver Signature and Date: ___________________________________________________ City of Peoria, Illinois (IL0037800) - May 20, 2025 INTRODUCTION On May 20, 2025, representatives from the U.S. Environmental Protection Agency, Region 5 conducted a Compliance Evaluation Inspection regarding the City of Peoria ("City" or "Peoria") combined sewer system. The purpose of this inspection was to evaluate Peoria's compliance with portions of the Clean Water Act (CWA) and the 2021 Consent Decree with the United States and the State of Illinois. This inspection consisted of the following: an opening conference, the green infrastructure (GI) projects that Peoria has implemented, the future GI and combined sewer overflow (CSO) remedial measures Peoria is considering, a walkthrough of the GI sites throughout the City, and a closing conference. Any findings and concerns that EPA identified during the inspection are listed in the section entitled "Areas of Concern" starting on page 15 of this report. BACKGROUND Peoria is a city in Central Illinois with a population of 110,460 people. The City owns and operates a combined sewer system (CSS) designed to collect and convey municipal sewage and stormwater to a wastewater treatment plant (WWTP) owned and operated by the Greater Peoria Sanitary District (GPSD). All of Peoria's 8.3 square miles of the combined sewer system is tributary to the Riverfront Interceptor, along with 3.9 square miles of the separate sewer system. The Riverfront Interceptor run southwest parallel to the Illinois River. Along the Riverfront Interceptor there are 16 CSO outfalls through which combined sewage is discharged to the Illinois River. The CSO discharges are controlled, in part, by 19 CSO regulators. National Pollutant Discharge Elimination System Permit The Illinois Environmental Protection Agency (Illinois EPA) issued this facility a National Pollutant Discharge Elimination System (NPDES) Permit (Permit Number IL0037800) that regulates the discharge of its CSOs. This NPDES Permit was effective on June 1, 2006 and expired on May 31, 2011. The Permit is currently administratively extended. Note that previous to the issuance of this Permit, Peoria's CSOs were regulated under other versions of the NPDES Permit with the same NPDES permit number. The requirements of the effective Permit include the following: Identifying Peoria's 16 CSO outfalls: o Outfall 001 (Green Street) - discharges to Peoria Lake/Illinois River o Outfall 003 (Spring Street) - discharges to Peoria Lake/Illinois River o Outfall A06 (Old Eaton Street) - discharges to Peoria Lake/Illinois River o Outfall B06 (New Eaton Street) - discharges to Peoria Lake/Illinois River o Outfall A07 (Fayette Street) - discharges to Illinois River o Outfall 008 (Hamilton Street) - discharges to Illinois River o Outfall 009 (Fulton Street) - discharges to Illinois River o Outfall 010 (Liberty Street) - discharges to Illinois River o Outfall 011 (Harrison Street) - discharges to Illinois River o Outfall 013 (Walnut Street) - discharges to Illinois River o Outfall 014 (State Street) - discharges to Illinois River 2 City of Peoria, Illinois (IL0037800) - May 20, 2025 o Outfall 016 (Cedar Street) - discharges to Illinois River o Outfall 017 (South Street) - discharges to Illinois River o Outfall 018 (Sanger Street) - discharges to Illinois River o Outfall 019 (Darst Street) - discharges to Illinois River o Outfall 020 (Main Street) - discharges to Illinois River Sampling requirements for Outfalls A06, B06, and A07. Requirement to meet the Nine Minimum Controls, including the prohibition of dry weather overflows. Identification that some or all of the City's CSOs discharge into sensitive areas. Requirement that Peoria develop a CSO operation and maintenance plan. 2021 Consent Decree On March 3, 2021, the City, the United States, and the State of Illinois finalized a consent decree (CD) with the U.S. District Court for the Central District of Illinois (Court) to address CSOs occuring from the City of Peoria's combined sewer system. Under this CD, Peoria will develop and then implement, after EPA and Illinois EPA approval1, a CSO Remedial Measures Program to be completed by January 1, 2040. The purpose of this plan is to significantly reduce CSOs discharged to the Illinois River and Peoria Lake. After the approval of the CSO Remedial Measures Program, Peoria will implement its CSO remedial measures, including Green Infrastructure, in order to meet its interim performance criteria at years 4 (2026), 7 (2029), 10 (2032), and 14 (2036) into CD implementation. These interim performance criteria milestones consist of reducing the CSO volume discharged and the CSO individual events at increasing percentages as the implementation of the CSO Remedial Measures Program gets closer to the completion date. The reduction percentages will be computed by using real data acquired during the applicable milestone year at Peoria's CSO flow meters and then comparing that data to Peoria's Starting Conditions hydrologic and hydraulic model output using the applicable milestone year's precipitation data. Peoria must comply with the following Final Performance Criteria once it completes the implementation of its CSO Remedial Measures Program: No modeled CSOs in a Six-Month Design Storm identified in the CD; One modeled CSO in Peoria's Typical Year; Limiting the modeled CSO volume discharged during July 21, 1949 storm to no more than 16.3 million gallons; and No CSOs during a precipitation event equal to or smaller than Peoria's Six-Month Design Storm event and Peoria's Typical Year precipitation events. Peoria must begin implementing its Post-Construction Monitoring Plan after the completion of its CSO Remedial Measure Program. The Post-Construction Monitoring Plan will include a 1 EPA and Illinois EPA approved Peoria's CSO Remedial Measures Plan on August 22, 2024 3 City of Peoria, Illinois (IL0037800) - May 20, 2025 monitoring timeframe of at least two years, include a relevant water quality assessment of the effects of the residual CSO discharges on the Illinois River and Peoria Lake and will determine if Peoria has met its Final Performance Criteria. After the monitoring is complete, Peoria will submit a report to EPA and Illinois EPA demonstrating that it has complied with the PostConstruction Monitoring Plan and the CD's Final Performance Criteria. Receiving Waters As previously mentioned, Peoria's CSOs discharge to the Illinois River and Peoria Lake. The Illinois River is delineated as a permanent river on the USGS National Map, with Peoria Lake being a wide section of the Illinois River. The Illinois River and Peoria Lake is impaired for primary contact recreation due to high concentrations of fecal coliform bacteria. In addition, the Illinois River and Peoria Lake is impaired for mercury, pesticides and polychlorinated biphenyls. SITE INSPECTION Exhibit 1: City of Peoria Location Source: Google Maps (2025) Initial Inspection Discussion The EPA inspection team, consisting of Mr. Middleton and Mr. Jones, and the Illinois EPA inspection team, consisting of Ms. Soucie and Mr. Phelps, met at the City of Peoria public works facility at approximately 8:40 am on Tuesday, May 20, 2025. The weather was mostly cloudy, with a temperature of approximately 65 Fahrenheit at the start of the inspection. It had rained approximately 1-inch in the early morning of the inspection and would also later rain in the afternoon during EPA's walkthrough of Peoria's implemented GI. After parking in the facility's parking lot south of the public works building, the EPA inspectors met up with the Illinois EPA 4 City of Peoria, Illinois (IL0037800) - May 20, 2025 inspectors and then entered the public works building. EPA and Illinois EPA inspectors were shown to a conference room on the southwest side of the building where City of Peoria (Andrea Klopfenster, Paola Mendez-Silvagnoli, Sie Maroon) and Mead & Hunt (Amy Post and Eric Carlson, with Kyla Dean joining by video conference) representatives were waiting. After explaining the purpose of the EPA inspection, Mr. Middleton and Mr. Jones then presented their EPA inspector credentials to the Peoria and Mead & Hunt representatives. Next, EPA discussed EPA's Confidential Business Information (CBI) provisions, notified Peoria that EPA would be requesting documents and taking pictures during the walkthrough of Peoria's implemented projects, and proposed a tentative schedule for the inspection. Year 1 CSO Control Project EPA and Illinois EPA inspectors then began asking Peoria and Mead & Hunt representatives about Peoria's first set of green infrastructure (GI) projects implemented after the CD was entered, named the Year 1 CSO Control Project. Most of EPA's and Illinois EPA's questions during these discussions were answered by Ms. Dean, via videoconference. Also, during this conversation, Rick Powers, Peoria Public Works Director, joined the inspection discussion. A summary of the Year 1 CSO Control Project discussions is provided below: The GI projects implemented within this group of projects included 14 blocks of permeable paver parking lanes with 20 stormwater bump-outs. The total stormwater storage provided is 400,000 gallons. These projects were completed in June 2023. The GI projects were all implemented within the Spring Street (Outfall 003) sewershed. Projects were targeted within areas of high native soil infiltration. PaveDrain paver blocks were used in the permeable paver parking lanes projects with subsurface storage located underneath the paver blocks (except for the projects located along Mary Street). The permeable paver projects along Mary Street are attached to StormChambers, a stormwater storage/conveyance structure. Initially mulch was used within the stormwater bump-outs. Peoria informed EPA and Illinois EPA during the inspection that the mulch had been removed and the stormwater bump-outs were scheduled to be re-planted soon by Pizo Nursery. Six INFIL trackers are utilized throughout the implemented Year 1 CSO Control Project. These INFIL trackers measure the water surface elevation every 10 minutes in the subsurface storage areas. Peoria mentioned during the inspection there were some utility conflicts with the implementation of GI projects, particularly along Mary Street. In addition, the permeable paver projects implemented along Mary Street did not meet the projected infiltration rates. Peoria representatives believed that the geofabric mesh that kept solids out of the StormChambers was getting clogged and not allowing captured stormwater to flow to the StormChambers. 5 City of Peoria, Illinois (IL0037800) - May 20, 2025 Year 2 CSO Control Project Next EPA and Illinois EPA inspectors began talking about Peoria's implemented Year 2 CSO Control Project. A summary of the Year 2 CSO Control Project discussions is provided below: The GI projects implemented within this group of projects included 25 blocks of permeable paver parking lanes, 2 blocks with full width porous asphalt, and with 53 stormwater bump-ins. The total stormwater storage provided is 800,000 gallons. These projects were completed ahead of schedule in December 2024. The GI projects were all implemented within the Cedar Street (Outfall 016) sewershed. Projects were targeted within areas of high native soil infiltration. PaveDrain permeable paver blocks were used in the permeable paver parking lanes projects with subsurface storage located underneath the paver blocks. All of the permeable paver block projects within the Year 2 CSO Control Project utilized perforated pipes to direct flow through the subsurface aggregate storage. The porous asphalt project was incorporated on two segments within narrow blocks on Aiken Street and Kane Street. One of the porous pavement sections did not meet Peoria's performance objectives within the post-construction performance testing. Stormwater bump-ins is a type of inlet structure that was named by Peoria and Mead & Hunt representatives. This type of inlet structure is graded to pick up flow from the roadway and direct the flow into the subsurface storage area. The subsurface storage associated with bump-ins consists of aggregate with typically turf grass planted above it. One of the stormwater bump-in implemented within the Year 2 CSO Control Project did not meet the design infiltration rates within post-construction testing. Peoria has identified a stainless-steel mesh screen within inlet structures that screen solids from getting into the pipes that are connected to the subsurface storage below permeable pavers as a clogging issue. Peoria is looking to replace these screens with either a screen box (metal basket with screens), storm rings, cresent pipe design, or a snout inlet pipe (that draws from water beneath the floatables in the inlet structure). Year 3 CSO Control Project Then, EPA and Illinois EPA inspectors began discussing Peoria's implemented/proposed Year 3 CSO Control Project. A summary of the Year 3 CSO Control Project discussions is provided below: The GI projects implemented within this group of projects includes 8 blocks of permeable paver parking lanes, 5 subsurface infiltration facilities, and with 3 stormwater bump-ins. The total stormwater storage provided is 300,000 gallons. These projects are currently on-going; some of these projects are finished but ownership of the projects has not been turned over to the City. GI projects that are not owned by 6 City of Peoria, Illinois (IL0037800) - May 20, 2025 Peoria do not have maintenance occurring at these sites. Peoria representatives estimated that final full completion of all projects would be September 2025. The GI projects were all implemented within the Cedar Street (Outfall 016) sewershed; adjacent to the Year 2 CSO Control project. Projects were targeted within areas of high native soil infiltration. PaveDrain permeable paver blocks were used in the permeable paver parking lanes projects with subsurface storage located underneath the paver blocks. All of the permeable paver block projects were constructed similar to the Year 2 CSO Control projects. Subsurface infiltration facilities were constructed at low points in roadway intersections to maximize the collection of stormwater runoff. The stormwater bump-ins were designed in a matter similar to the stormwater bump-ins implemented within the Year 2 CSO Control project. For some of the finished Year 3 CSO Control project, the contractor used the same stainless-steel mesh screen that has had clogging issues within the other permeable pavers projects in the Year 2 CSO Control project. As with the Year 2 Control project, Peoria is looking into replacing these screens with a different type of filter structure. Year 4 CSO Control Project Then, EPA and Illinois EPA inspectors began discussing Peoria's proposed Year 4 Control CSO Projects. A summary of the Year 4 CSO Control Project discussions is provided below: The GI projects implemented within this group of projects includes 71 subsurface infiltration facilities below permeable pavers. The total stormwater storage provided is 900,000 gallons. These projects are currently being bid and may start in June 2025. The GI projects will be implemented within the Sanger Street (Outfall 018) sewershed. Pre-construction infiltration testing is completed and was used for locating the proposed Year 4 Control CSO project. Future GI Projects Next, the parties discussed some additional future GI projects. The MacArthur Highway Rehabilitation project consists of implementing 21 stormwater bump-ins attached to subsurface aggregate storage within the overall repair of this road. Peoria representatives told EPA that this project would take an estimated 2-years and it went out for bid on the day of this inspection. Overall, the total stormwater storage provided within these projects is 100,000 gallons. EPA, Illinois EPA, Peoria, and Mead & Hunt representatives also discussed potential future GI projects within the Spring Street Sewershed (Outfall 003). Peoria told EPA and Illinois EPA that it was looking into implementing four infiltration basins along streets that will have inlets connected to the basins. Currently, Peoria is looking for grant funding for these Spring Street GI 7 City of Peoria, Illinois (IL0037800) - May 20, 2025 projects. Peoria representatives also indicated that there were no other potential projects in design phase at the time of this inspection. In-system storage was discussed during the inspection. Peoria indicated to EPA and Illinois EPA that it was looking at several areas for in-system storage and had estimated potential benefits at three locations: 1.7 million gallons of in-system storage within the Darst Street Sewershed (Outfall 019) 1 million gallons of in-system storage within the Cedar Street Sewershed (Outfall 016) 0.6 million gallons of in-system storage within the Fayette Street Sewershed (Outfall A07) Peoria indicated that if the in-system storage was looked at further that basement backups in these areas would be evaluated. Peoria told EPA and Illinois EPA that both in-system and any offline storage implementations would need to be coordinated with GPSD. Note that after the inspection, Peoria indicated within documents that were presented to its city council on June 17, 2025 that in-system storage was significantly more expensive that originally estimated and was no longer recommended. Early GI Pilot Projects EPA, Illinois EPA, Peoria, and Mead & Hunt representatives then discussed the GI projects that were implemented throughout Peoria prior to the finalizing of the CD. Peoria and Mead & Hunt representatives noted that these projects did not meet its current GI performance criteria, and that Peoria was deciding how to proceed with these completed GI projects moving forward. The Adams Street GI Projects was implemented in 2016. These GI projects utilize stormwater curb cuts that are connected to bioswales in between the street and the sidewalk. The Western Avenue GI Projects were completed in 2023 and the Folkers Avenue GI Projects were completed in May 2018. Both of these projects feature permeable pavers that are different than the type of permeable pavers used in the CSO Year 1 CSO projects and dry wells. GI Inspection and Maintenance Tracking EPA, Illinois EPA, Peoria, and Mead & Hunt representatives next talked about how the City performs and tracks GI routine inspections and maintenance. At this point in the inspection, Mr. Powers had left the discussion and Mr. Sidney Maroon had joined. EPA learned that the GI routine inspections are done by Peoria personnel (3-4 inspectors including Mr. Sidney Maroon) and are performed using tablets linked to a georeferenced database that was developed by Peoria. Mr. Sidney Maroon walked EPA and Illinois EPA inspectors through the use of the tablets, showing how information is recorded in the tablet for a GI routine inspection. Peoria representatives told EPA and Illinois EPA that 12 GI inspections were performed in 2024 postrainfall. 8 City of Peoria, Illinois (IL0037800) - May 20, 2025 Peoria representatives informed EPA that Peoria maintenance staff will monitor the input by the inspectors and perform maintenance including unscheduled GI maintenance when indicated within the tablet. There are no emails or other alerts generated outside of the tracking database, so Peoria maintenance staff must log on to the tracking database to check for GI maintenance requirements. Mead & Hunt representatives indicated that they track 10 rain gauges within Peoria to determine when the rainfall threshold for routine inspections is met (rainfall with more than 1-inch of depth) and will email Peoria staff indicating which GI projects need to be inspected. Mr. Sidney Maroon indicated that there is a training protocol to teach inspectors how to use the GI inspection and maintenance tracking system. Mr. Carlson mentioned that the Peoria and Mead & Hunt staff were working on an Operation and Maintenance (O&M) Training Manual to identify the training that the Peoria GI inspectors would need if additional inspectors were trained. EPA requested the draft version of the O&M Training Manual for review, which Peoria submitted to EPA on June 27, 2025. Other Items Discussed: - Peoria personnel regularly maintain the projects once they are turned over to the City/Peoria's Stormwater Utility. - Peoria is working on determining the correct maintenance intervals for its GI projects. Currently, Peoria maintains its GI on a 3-6-month cycle. To determine the most efficient maintenance frequency, Peoria is performing additional infiltration testing and performing more frequent maintenance to its GI projects every two months. - Peoria recently purchased a new vacuum sweeper truck made by Bucher in February 2025. This vacuum sweeper is much more powerful than the other cleaning equipment Peoria has; however, the vacuum sweeper truck broke two weeks ago and was out for repair during the inspection. - The GI inspections done by Peoria personnel are performed using tablets linked to a georeferenced databased that was developed by Peoria. - Peoria's stormwater utility has 12 employees; Peoria's maintenance staff has 8-10 employees, although this staff does more than just maintain GI. - According to Peoria representatives no salt is used as a deicer in areas with GI. A regular snowplow blade is used in permeable paver areas when more than two inches of snow occurs, although Mr. Sie Maroon indicated the use of a rubber blade was being piloted. - Illinois Civil Contractors (ICCI) is the primary contractor that has implemented Peoria's GI projects after the CD was finalized. - So far through the implementation of the Year 1, 2, and 3 CSO Control Projects, the costs associated with the projects have been higher than estimated. Peoria representatives believed that this was in part due to some of the GI projects only having one contractor bid on the work. - Peoria believes there was one potential river water intrusion events into the combined sewer system may have occurred in January 2024, however confirmation was not 9 City of Peoria, Illinois (IL0037800) - May 20, 2025 possible due to a relevant GPSD flow meter being out-of-service. So far in 2025, Peoria did not think any river water intrusion events had occurred. Peoria representatives also indicated that it had discussed potential river flap gate issues with GPSD. Facility Walk-Through At approximately 1:00 pm, Mr. Middleton, Mr. Jones, Ms. Soucie, Mr. Phelps, Ms. Klopfenster, Ms. Mendez-Silvagnoli, Ms. Post, and Mr. Carlson, began a walk-through of selected GI infrastructure and associated maintenance equipment. The EPA and Illinois EPA inspectors observed 1 of the 2 vacuum trucks used by Peoria (Photographs 2 and 4 in Attachment A) and 1 of 2 of Peoria's vacuum sweeper trucks (Photograph 3 in Attachment A) in the parking lot just outside of the public works building. A cleaning attachment used for the vacuum trucks (Photograph 1 in Attachment A) was also available for EPA and Illinois EPA to view. EPA representatives then talked more with the Peoria representatives about the GI maintenance equipment. The vacuum trucks require two employees to operate each truck, with the vacuum sweeper trucks requiring only one. Both trucks use water that is refilled as needed during typical operation of the trucks. Compressed air can also be used to enhance the cleaning potential of the trucks. Peoria representatives again informed EPA and Illinois EPA that the new vacuum sweeper truck, manufactured by Bucher, had a hydraulic issue that required repair. This truck broke down approximately three weeks before the inspection and is still out of service. Peoria's maintenance truck operators estimated the cleaning times for a typical section of permeable pavers as follows: 5 minutes for the new Bucher vacuum sweeper truck, 30 minutes when compressed air is used with one of the other trucks, and 1-2 hours when just water is used with one of the other trucks. After observing the GI infrastructure maintenance equipment, EPA, Illinois EPA, Peoria, and Mead & Hunt representatives left Peoria's public works building to drive to different implemented GI infrastructure throughout the Peoria's combined sewer system. These sites were chosen by EPA, with input from Peoria and Mead & Hunt representatives. The first location that was observed was permeable paver sections and stormwater bump-outs at the intersection of Perry Avenue and Mary Street within the Year 1 CSO project area. The stormwater bump-out shown in Photograph 5 in Attachment A are connected to StormChambers stormwater subsurface storage units located underneath the permeable pavers in Photograph 8 in Attachment A. There is another inlet upstream of the permeable pavers that collects flow on Mary Street, in addition to the collection of stormwater flow from Perry Avenue via the stormwater bump-out. In the stormwater bump-outs located in this area, EPA observed that there was little/no vegetation present. Ms. Klopfenster told EPA that these stormwater bumps would be replanted in the next couple of weeks as discussed earlier in the inspection. Near the stormwater inlet within the southern stormwater bump-out on Perry Avenue, EPA noticed evidence of prior erosion of soil and mulch from the stormwater bump-out into the inlet (Photograph 6 in Attachment A). As EPA, Illinois EPA, Peoria, and Mead & Hunt representatives continued to discuss the GI in this area, the parities discussed the issue with StormChambers storage and the geofabric mesh 10 City of Peoria, Illinois (IL0037800) - May 20, 2025 within that Peoria believed had become partially obstructed with solids that limited the infiltration into the native soil underneath the StormChambers. Peoria indicated that they were looking into replacements for the geofabric mesh to allow for more infiltration with solids control further upstream at the inlets of the GI infrastructure. EPA then observed a cleanout associated with the permeable pavers/stormwater chambers (Photograph 7 in Attachment A). This cleanout appeared to have a good deal of solids within the structure at the time of this inspection. Peoria representatives mentioned that they believed the alley (shown in Photograph 8 in Attachment A) contributed to more solids within the permeable paver sections, related to dust and debris from garbage cans/garbage pickup. Next, EPA, Illinois EPA, Peoria, and Mead & Hunt representatives drove to another permeable pavers section on Laveille Street, between Monroe Street and Madison Avenue in the Year 1 CSO Control Project area. Photograph 10 in Attachment A shows the permeable paver section in this area with a zoomed in view of the permeable pavers in Photograph 11 in Attachment A. The permeable pavers are setup differently here than previously observed on Mary Street, with only aggregate used within the subsurface storage and a 12-inch perforated pipe that runs within the subsurface storage to distribute the influent. Peoria representatives noted that this section of permeable pavers had been cleaned within the last two weeks. EPA observed very little debris within the permeable pavers in this area. The cleanout associated with the permeable pavers also had fewer solids and debris than the cleanout viewed on Mary Street (Photograph 12 in Attachment A). EPA then walked to the northwest up Laveille Street to observe the stormwater bump-out on the southside of Perry Street (Photograph 13 in Attachment A). EPA noticed at this stormwater bump-out that there was additional evidence of prior soil erosion into the inlet connected to the subsurface storage under the permeable paver section on Laveille Street. Peoria and Mead & Hunt representatives then informed EPA that this stormwater bump-out would also be replanted in a similar fashion to the stormwater bump-outs observed previously. EPA next walked to the northeast along Perry Street to observe the permeable paver section located here (Photograph 14 in Attachment A). Mead & Hunt representatives noted that the design of the inlet being in the street and not located on the curb was different than other permeable paver project implementations throughout Peoria. EPA learned that this was due to the use of previous inlets located here to save costs. EPA, Illinois EPA, Peoria, and Mead & Hunt representatives then drove to the southeast to the intersection of Madison Avenue and Mary Street to observe a INFIL tracker device within the Year 1 CSO Project area (Photograph 15 in Attachment A). Mr. Carlson then explained how the INFIL tracker measured the water surface elevation within the subsurface storage. EPA also learned that this information is uploaded to cloud storage and then available for analysis after the precipitation event. After observing the INFIL tracker device, EPA, Illinois EPA, Peoria, and Mead & Hunt representatives next drove to the Year 2 CSO Project area. During the drive to the Year 2 CSO Project area, the light rain that had started to occur as the parities viewed the Year 1 CSO Project intensified to a heavy downpour. At the intersection of West John H. Gwynn Jr. Avenue and 11 City of Peoria, Illinois (IL0037800) - May 20, 2025 North Webster Street, EPA observed permeable pavers located on John H Gwynn Jr. Avenue and Webster Street. Although the permeable pavers appeared to be keeping up with the rainfall, a nearby CSO inlet was taking the majority of stormwater inflow west on John H. Gwynn Jr. Avenue and the sidewalk on Webster Street to the south (Photograph 16 in Attachment A). EPA, Illinois EPA, Peoria, and Mead & Hunt representatives walked to the east to observe the permeable pavers on John H. Gwynn Jr. Avenue. EPA looked into the stormwater inlet connected to the subsurface storage under the permeable pavers and observed a small amount of debris. Mead & Hunt representatives also pointed out the flat stainless-steel mesh screen located on the inlet pipe (above the white PVC pipe in Photograph 17 in Attachment A) that screened out solids before entry into the subsurface storage. Mead & Hunt representatives believed that this screen would clog frequently during storm events and Peoria was considering different upgrades to address this problem. Peoria, and Mead & Hunt representatives also pointed out to EPA that the inlet located across the street connected to GI infrastructure on the north side of John H. Gwynn Jr. Avenue was connected to the inlet on the other side of the street for redundancy. EPA then continued to walk to the east and observed the cleanout associated with the permeable pavement/subsurface storage on John H. Gwynn Jr. Avenue (Photograph 18 in Attachment A). As with the associated inlet, there was only a small amount of debris in the clean out. After viewing the cleanout, Ms. Klopfenster and Ms. Mendez-Silvagnoli left the inspection to attend another meeting. Next, EPA, Illinois EPA, and Mead & Hunt representatives drove south down Webster Street to Aiken Street to observe a porous asphalt implementation on Aiken Street between Webster Street and Charlton Street (Photographs 19 and 20 in Attachment A). Mead & Hunt representative mentioned to EPA that this section of Aiken Street was chosen for porous asphalt because the width of the roadway was short and there was no garbage pickup on this street. EPA observed areas of heavy ponding on the porous asphalt, which indicated problems with infiltration through the pavement due to clogging. Mead & Hunt representatives indicated that the new Bucher sweeper vacuum truck had recently cleaned the street and increased the infiltration of the porous asphalt from 5 inches per hour to 59 inches per hour. While at this location, EPA observed a number of mature bushes and trees in this area that could contribute debris that could clog the porous pavement, along with garbage cans out for pickup. Then EPA, Illinois EPA, and Mead & Hunt representatives left the porous asphalt area and the Year 2 CSO Project area and drove to the southwest to the intersection of McBean Street and Charlton Street in the Year 3 CSO Project area. At this location, EPA observed what Peoria and Mead & Hunt representatives refer to as a stormwater bump-in (Photograph 21 and 23 in Attachment A). The subsurface storage at McBean Street and Charlton Street associated with the stormwater bump-in is located in the grass right-of-way on the westside of Charlton Street. Mead & Hunt representatives told EPA that the subsurface storage typically includes aggregate at a 4-feet deep, unless there are utility conflicts that cause a shallower aggregate depth. EPA noticed that the stormwater bump-in inlet associated with the subsurface storage was flooded; Mead & Hunt representatives informed EPA that this GI infrastructure also had a flat stainlesssteel mesh on the inlet pipe and it was probably clogged. Peoria informed EPA and Illinois EPA 12 City of Peoria, Illinois (IL0037800) - May 20, 2025 that it is currently working through this issue. EPA also observed the cleanout associated with the subsurface storage (Photograph 22 in Attachment A); this cleanout appeared to have little to no debris within it. EPA, Illinois EPA, and Mead & Hunt representatives next drove a short distance to the intersection of McBean Street and Steubenville Street to observe on-going GI construction (Photograph 24 in Attachment A). Mead & Hunt representatives, including Ms. Dean by phone, explained to EPA and Illinois EPA inspectors that this project would add permeable pavers to both sides of the street of Steubenville Street, from McBean Street north to Aiken Street. In addition to implementing the permeable pavers, the roadway would be rebuilt with conventional asphalt. Next, EPA, Illinois EPA, Mead & Hunt representatives drove to the west to see a subsurface infiltration below pavement project at the intersection of Kettealle Street and DuSable Street. Peoria representatives explained that the subsurface storage is located under the paved intersection. The inlets that were connected to the subsurface storage in this location were located at a lower elevation than nearby combined sewer overflow inlets. EPA observed in this location substantial street flooding (Photograph 25 and 26 in Attachment A), with the floodwaters only entering the combined sewer overflow inlets. Mead & Hunt representatives indicated that the construction contractor that performed this work, ICCI, used the same problematic flat stainless-steel mesh on the inlet pipes. Mead & Hunt representatives said that Peoria was planing on replacing the stainless-steel mesh with a different screening structure. Mead & Hunt representatives also informed EPA and Illinois EPA that none of the Year 3 CSO Projects had been turned over to the City of Peoria at the time of the inspection. EPA, Illinois EPA, and Mead & Hunt representatives then drove north to the intersection of Hinton Street and Sand Street to view a permeable pavement section on Hinton Street (Photograph 27 in Attachment A). EPA noticed here that the permeable paver section was only on the southside of Hinton Street and the permeable paver section was wider than the other permeable pavement implementation previously viewed. Mead & Hunt representatives, with Ms. Dean on the phone, told EPA and Illinois EPA that there were utility conflicts with implementing the permeable pavement on the north side of the street. Hinton Street also appeared to be slightly graded from north to south to allow for runoff from the street to flow to the permeable pavement. Mead & Hunt representative also told EPA inspectors that the two inlets near the intersection of Hinton Street and Sand Street were likely connected to subsurface storage in this area. Then EPA, Illinois EPA, and Mead & Hunt representatives drove to the west to view a permeable pavement section and dry well project, implemented prior to the CD, on Western Avenue. After parking near the intersection of Proctor Street and Western Avenue, EPA inspectors observe the inlets to the wet wells located on Proctor Street were covered with debris (Photograph 28 in Attachment A). EPA then viewed the permeable pavement section on Western Avenue (Photograph 29 in Attachment A). Overall, EPA observed only limited ponding on the permeable pavement in this area, with most sections of permeable pavement 13 City of Peoria, Illinois (IL0037800) - May 20, 2025 either dry or slightly wet. Peoria staff still performs maintenance on these GI projects, just not at the level that it does maintenance on the Year 1 or Year 2 CSO Project areas. Peoria also does not perform the frequent GI project testing, pursuant to the consent decree. Next, EPA, Illinois EPA, and Mead & Hunt representatives drove back to the east to see a permeable pavement section on Blaine Street, between Smith Street and Martin Street (Photograph 30 in Attachment A). This permeable project was implemented as a part of the Year 3 CSO Project. EPA observed heavy ponding on most of the implemented permeable pavement, indicating that the permeable pavement here was clogged and/or not performing as designed. Mead & Hunt representatives told EPA that this project was finished near the end of 2024, but had not been turned over to Peoria for ownership and therefore maintenance was not occuring. EPA, Illinois EPA, and Mead & Hunt representatives then drove southeast to the intersection of Martin Street and Warren Street to observe a subsurface infiltration, located below the intersection, similar to the project located at the intersection of Kettealle Street and DuSable Street (Photograph 31 in Attachment A). Mead & Hunt representatives told EPA that the aggregate storage was located in a crescent shape on the east and south of the intersection. There were also two inlets shown on Photograph 33 there were connected to the storage. EPA observed that a dirt area was up gradient of both inlets was not stablized and could have the potential to erode into the inlets. There was also dirt from the construction located around the inlets. Then, EPA, Illinois EPA, and Mead & Hunt representatives drove west to the Trewyn Middle School to observe permeable paver sections on Folkers Avenue, between Fremont Street and Latrobe Street (Photograph 34 in Attachment A). Like the Western Street permeable paver sections, the Folkers Avenue permeable paver project was implemented before the consent decree was finalized. Mead & Hunt representatives indicated it performs maintenance on these GI projects, just not at the level that it does maintenance on the Year 1 or Year 2 CSO projects. EPA observed some standing water on portions of the permeable paver section (Photograph 34 in Attachment A), indicating some potential clogging. EPA, Illinois EPA, and Mead & Hunt representatives also walked over to the intersection of Folkers Street and Humboldt Street to view a dry well implementation before leaving the area. The last area that EPA, Illinois EPA, and Mead & Hunt representatives observed was the GI projects implemented on Adams Street (Photograph 36 and 37 in Attachment A). Mead & Hunt representatives explained to EPA and Illinois EPA inspectors that Peoria implemented bioswales near the street that accepted runoff from the street through curb cuts in 2016. There are also dry wells located near the intersection of Spencer Street and Adams Street. These were some of the first GI projects implemented in Peoria and were considered pilot projects. Mead & Hunt representatives informed EPA and Illinois EPA that it was determined that permeable pavers had a better infiltration rate than the bioswales and the permeable paver GI projects were less expensive than the bioswales. 14 City of Peoria, Illinois (IL0037800) - May 20, 2025 EPA finished its walk-through of the Peoria's GI Projects at approximately 5:30 pm and drove back to Peoria's public works building for a closing conference. Closing Conference Mr. Middleton began the closing conference in the public works building's conference room at approximately 6:05 pm. Mr. Middleton, Mr. Jones (U.S. EPA), Ms. Soucie, Mr. Phelps (Illinois EPA), Ms. Post, and Mr. Carlson (Mead & Hunt) were all present for the closing conference. EPA went over the preliminary concerns it found during its inspection, some of which are listed below. EPA also told Ms. Post and Mr. Carlson that it would develop an inspection report that summarized its inspection of this facility and anticipated that it would provide a copy of the report in approximately 60 days to the Facility. EPA then answered Ms. Post's and Mr. Carlson's questions related to the inspection and EPA confirmed that it had not obtained any information or taken any pictures that were considered CBI and the closing conference ended at approximately 6:20 pm. EPA ended the inspection and exited the facility at approximately 6:25 pm. DOCUMENTS OBTAINED DURING THE INSPECTION: A. Assorted As-Built Plan Sets for Year 1 CSO Control Projects, Year 2 CSO Control Projects, and Year 3 CSO Control Projects DOCUMENTS OBTAINED AFTER THE INSPECTION: A. Peoria GI Rain Gauge Assessment, dated June 6, 2025 B. 2024 Permeable Paver Inspection and Maintenance Summary for Y1_PP-22 C. Operations and Maintenance Training Reference Manual - Draft Version, dated June 27, 2025 AREAS OF CONCERN: EPA has identified areas of concern based on findings during the inspection of the City of Peoria Combined Sewer System/Consent Decree Oversight Inspection and based on a post-inspection review of the information provided to EPA by Peoria representatives. An enumerated list of the areas of concern are listed below: 1. Snow Removal for Permeable Pavement: In Section 4.1 of Peoria's approved CSO Remedial Measures Program Operations and Maintenance and GI Performance Testing Plan (page 13), Peoria wrote that salt should not be applied to permeable pavement surfaces and rubber blades should be used for snow plowing. Peoria representatives indicated that it was piloting the use of a rubber blades. 2. GI Project Placement and Grading: During EPA's walkthrough and observation of some of Peoria's implemented GI projects during heavy rainfall, it appeared that in some cases, 15 City of Peoria, Illinois (IL0037800) - May 20, 2025 the GI project inlet was not positioned or graded to fully capture stormwater runoff. Particularly, EPA observed this condition at the intersection of West John H Gwynn Jr Avenue & North Webster Street and the intersection of McBean Street & Charlton Street. Peoria's GI designs appear to be focused on the native soil infiltration, with less focus on the estimated stormwater runoff that is tributary to the project. In addition, EPA observed runoff in two areas with GI projects that was not going into inlets that are connected to the GI projects and was instead going into combined sewer system inlets. 3. Stormwater GI Stainless-Steel Mesh Screen: During the inspection, EPA was informed by Peoria and Mead & Hunt representatives that there was an issue with the stainlesssteel mesh screen that screens stormwater flow into GI from the inlets. The issues with the clogging of this stainless-steel mesh screen caused street flooding in two observed GI areas. During the heavy rain event, it also appeared, due to this clogging, stormwater runoff was entering the combined sewer system, which may have caused or contributed to additional CSO discharge. Peoria and Mead & Hunt indicated to EPA that they are working on a number of solutions to resolve the issue and are currently piloting some of these potential solutions right now. 4. Ownership Turnover of Finished GI Projects to Peoria: During the inspection, EPA learned there is a period of time where the GI project is finished by the contractor and when the ownership of the GI project is assumed/turned over to the City. EPA's understanding is that during this transition time there is no maintenance being performed on the implemented GI. EPA is concerned that the lack of maintenance that occurs during this time may lead to the diminished performance of the GI. For example, the permeable pavement on Blain Street (in between Smith Street and Martin Street) was observed by EPA to have significant ponding present on the permeable pavement (Photograph 30 in Attachment A) during the inspection. Mead & Hunt representatives told EPA that this project had been completed at the end of the year, meaning that no maintenance had been performed for approximately 5 months by either the contractor or Peoria. Given the ponding, the permeable pavement system may be clogged. It is unclear if resuming regular maintenance can fully restore the intended performance of the GI. 5. Temporary Best Management Practices to Address Soil Erosion for GI Projects: EPA learned during the inspection that some of the vegetation in the stormwater bump-outs in the Year 1 CSO Control Projects had died off and the stormwater bump-outs needed to be replanted. EPA's understanding is that this replanting is either completed or on-going. EPA is concerned that until this replanting occurs without a plan for best management practices, soil erosion can occur into the subsurface storage features. EPA also observed some potential for soil erosion that could enter the stormwater inlets connected to the subsurface infiltration GI project located at the intersection of Kettealle Street and DuSable Street. 6. Porous Asphalt Project Location: During the inspection, EPA went to a porous asphalt GI implementation on Aiken Avenue (Photograph 19 in Attachment A) and observed 16 City of Peoria, Illinois (IL0037800) - May 20, 2025 ponding on the porous asphalt, indicating clogging. One of the porous pavement sections did not meet Peoria's performance objectives within the post-construction performance testing. Peoria and Mead & Hunt representatives pointed out that several circumstances were considered to identify the location of porous asphalt implementation, including if garbage pickup occurred on the street. Potential sources along the road that could contribute solids/debris included garbage cans (that appeared to be collected along the street) and mature trees/bushes. 7. Folkers Avenue Permeable Pavement Clogging: EPA observed during the inspection that there was water ponding on the permeable pavement that had been implemented on Folkers Avenue. This ponding may indicate that the permeable pavement is clogged, at least in certain sections of this GI. 8. GI Costs and Future Plans: After the inspection, EPA learned that Peoria held a special city council meeting on June 17, 2025 to discuss the CSO Remedial Measures plan. Information regarding the discussion was provided on Peoria's website (https://peoriagov.civicweb.net/document/222199). On page 53 of the PowerPoint presentation slides, Peoria indicated that the cost per gallon of CSO control using GI has increased by 3.8 times. Although EPA and Peoria discussed during the inspection issues with Peoria's GI implementation, including costs, the degree of potential cost increases was not mentioned. Nor did EPA and Peoria discuss during the inspection that Peoria was considering implementing a 6.4-million-gallon offline storage tank at the Cedar Street Bridge, as presented in the PowerPoint slides. EPA is concerned that this important issue was not mentioned during the inspection, specifically when the topic of offline storage was discussed. EPA notes that Peoria's CD would allow Peoria to pivot between GI and gray infrastructure, as long as the CD's interim performance criteria milestones were met. LIST OF ATTACHMENTS: A. Photograph Log 17 Attachment A: City of Peoria Combined Sewer Overflow Inspection Photograph Log U.S. EPA Inspection - May 21, 2025 All photos taken by Keith Middleton, Environmental Engineer, U.S. EPA Camera: Canon PowerShot SX230 HS (Photographs 1-20) and Pentax Optio WG-1 GPS (Photographs 21-37) *Note that the Pentax camara did not record photograph times **Licenses plates in photographs were removed 1: IMG_1283 Description: Vacuum Truck Cleaning Attachment Location: City of Peoria - Public Works Building Camera Direction: N/A Date/Time: May 20, 2025 - 1:00 pm CDT Page 1 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 6: IMG_1288 Description: Inlet Within Stormwater Bump-Out in IMG_1187 Location: City of Peoria - NE Perry Avenue & Mary Street Intersection Camera Direction: N/A Date/Time: May 20, 2025 - 1:48 pm CDT 7: IMG_1289 Description: Cleanout Associated with Permeable Paver Section on Mary Street Location: City of Peoria - Mary Street, Southeast of NE Perry Avenue Camera Direction: N/A Date/Time: May 20, 2025 - 1:50 pm CDT Page 4 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 10: IMG_1292 Description: Permeable Paver Section on Laveille Street Location: City of Peoria - Laveille Street - Between NE Monroe Street and NE Madison Ave. Camera Direction: Southeast Date/Time: May 20, 2025 - 2:05 pm CDT 11: IMG_1293 Description: Permeable Paver Section on Laveille Street Location: City of Peoria - Laveille Street - Between NE Monroe Street and NE Madison Ave, Just Southeast of an Alley Camera Direction: N/A Date/Time: May 20, 2025 - 2:06 pm CDT Page 6 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 14: IMG_1296 Description: Permeable Paver Section on NE Monroe Street Location: City of Peoria -Northeast of NE Monroe Street & Laveille Street Intersection Camera Direction: Northeast Date/Time: May 20, 2025 - 2:15 pm CDT Page 8 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 15: IMG_1297 Description: INFIL Tracker Monitoring System Location: City of Peoria -NE Madison Ave & Mary Street Intersection Camera Direction: Southeast Date/Time: May 20, 2025 - 2:20 pm CDT Page 9 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 16: IMG_1298 Description: Combined Sewer System Inlet Location: City of Peoria -West John H Gwynn Jr Ave & North Webster Street Intersection Camera Direction: Northwest Date/Time: May 20, 2025 - 2:34 pm CDT Page 10 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 17: IMG_1299 Description: Inlet to Permeable Pavers Section Location: City of Peoria -West John H Gwynn Jr Ave Webster Street Intersection Camera Direction: N/A Date/Time: May 20, 2025 - 2:39 pm CDT - East of John H Gwynn Jr Ave & North Page 11 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 20: IMG_1302 Description: Porous Asphalt Section on Aiken Ave. (2) Location: City of Peoria -Aiken Ave - Between N. Webster St. and S. Charlton St. Camera Direction: West Date/Time: May 20, 2025 - 2:54 pm CDT 21: IMGP0001 Description: Stormwater Bump-in Location: City of Peoria - Intersection of W. McBean St & S. Charlton St. Camera Direction: N/A Date/Time: May 20, 2025 - N/A Page 13 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 28: IMGP0008 Description: Inlet Connect to Wet Well (Southside of Street) Location: City of Peoria - Intersection of W. Proctor St & S. Western Avenue Camera Direction: Northwest Date/Time: May 20, 2025 - N/A 29: IMGP0009 Description: Permeable Pavement Section on Western Avenue Location: City of Peoria - Intersection of W. Proctor St & S. Western Avenue Camera Direction: South Date/Time: May 20, 2025 - N/A Page 17 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 32: IMGP0012 Description: Subsurface Infiltration Below Pavement Location: City of Peoria - Intersection of W. Martin St & S. Warren St Camera Direction: Northeast Date/Time: May 20, 2025 - N/A 33: IMGP0013 Description: Erosion Around the Inlets Associated with the Subsurface Infiltration Location: City of Peoria - Intersection of W. Martin St & S. Warren St Camera Direction: Northeast Date/Time: May 20, 2025 - N/A Page 19 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 34: IMGP0014 Description: Permeable Paver Sections; West of Trewyn Middle School Location: City of Peoria - Folkers Ave; Between W. Latrobe St & W. Fremont St Camera Direction: South Date/Time: May 20, 2025 - N/A 35: IMGP0015 Description: Permeable Paver Sections; West of Trewyn Middle School Location: City of Peoria - Folkers Ave; Between W. Latrobe St & W. Fremont St Camera Direction: Northwest Date/Time: May 20, 2025 - N/A Page 20 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025 36: IMGP0016 Description: Bioswale; North side of Street Location: City of Peoria - SW Adams Street; Near Intersection of SW Adams St. and Spencer St. Camera Direction: Northeast Date/Time: May 20, 2025 - N/A 37: IMGP0017 Description: Bioswale South side of Street Location: City of Peoria - SW Adams Street; Near Intersection of SW Adams St. and Spencer St. Camera Direction: Southeast Date/Time: May 20, 2025 - N/A Page 21 City of Peoria CSO Inspection - Peoria, Illinois May 20, 2025