HomeMy WebLinkAbout29 Draft SWPPPOSBORN C ONSULTING, I NC.
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Construction Stormwater General Permit (CSWGP)
DRAFT Stormwater Pollution Prevention
Plan (SWPPP)
for
City of Renton SE 172nd St and 125th Ave SE GSI Project
Prepared for:
The Washington State Department of Ecology
Northwest Regional Office
Permittee / Owner Developer Operator / Contractor
City of Renton City of Renton TBD
City of Renton, Washington
Certified Erosion and Sediment Control Lead (CESCL)
Name Organization Contact Phone Number
TBD TBD TBD
SWPPP Prepared By
Name Organization Contact Phone Number
Chang Liu Osborn Consulting, Inc. (425) 451-4009
SWPPP Preparation Date
June 10, 2021
Project Construction Dates
Activity / Phase Start Date End Date
TBD TBD TBD
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Table of Contents
1 Project Information ................................................................................................................................ 1
1.1 Existing Site Conditions ................................................................................................................. 1
1.2 Proposed Construction Activities .................................................................................................. 2
1.2.1 Construction Phasing ............................................................................................................ 2
1.2.2 Construction Schedule .......................................................................................................... 2
2 Construction Stormwater Best Management Practices (BMPs) ........................................................... 1
2.1 Element 1: Preserve Vegetation/Mark Clearing Limits ................................................................. 1
2.2 Element 2: Establish Construction Access .................................................................................... 2
2.3 Element 3: Control Flow Rates ...................................................................................................... 2
2.4 Element 4: Install Sediment Controls ............................................................................................ 2
2.5 Element 5: Stabilize Soils .............................................................................................................. 3
2.6 Element 6: Protect Slopes ............................................................................................................. 3
2.7 Element 7: Protect Drain Inlets ..................................................................................................... 4
2.8 Element 8: Stabilize Channels and Outlets ................................................................................... 4
2.9 Element 9: Control Pollutants ....................................................................................................... 4
2.10 Element 10: Control De-watering ................................................................................................. 4
2.11 Element 11: Maintain BMPs ......................................................................................................... 4
2.12 Element 12: Manage the Project .................................................................................................. 5
2.13 Element 13: Protect Low Impact Development (LID) BMPs ......................................................... 6
3 Pollution Prevention Team .................................................................................................................... 7
4 Monitoring and Sampling Requirements ............................................................................................... 8
4.1 Site Inspection ............................................................................................................................... 8
4.2 Stormwater Quality Sampling ....................................................................................................... 8
4.2.1 Turbidity Sampling ................................................................................................................ 8
4.2.2 pH Sampling .......................................................................................................................... 9
5 Discharges to 303(d) or Total Maximum Daily Load (TMDL) Waterbodies ........................................ 10
5.1 303(d) Listed Waterbodies .......................................................................................................... 10
5.2 TMDL Waterbodies ..................................................................................................................... 10
6 Reporting and Record Keeping ........................................................................................................... 11
6.1 Record Keeping ........................................................................................................................... 11
6.1.1 Site Log Book ....................................................................................................................... 11
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6.1.2 Records Retention ............................................................................................................... 11
6.1.3 Updating the SWPPP ........................................................................................................... 11
6.2 Reporting..................................................................................................................................... 11
6.2.1 Discharge Monitoring reports ............................................................................................. 11
6.2.2 Notification of Noncompliance 12
Appendices
Appendix A – Site Map
Appendix B – Correspondence
Appendix C – Site Inspection Form
Appendix D – Construction Stormwater General Permit (CSWGP)
Appendix E – Contaminated Site Information – As Needed
Appendix F – Engineering Calculations – As Needed
Appendix G – Geotechnical Report – Under Separate Cover
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List of Acronyms and Abbreviations
Acronym / Abbreviation Explanation
303(d) Section of the Clean Water Act pertaining to Impaired Waterbodies
BMP(s) Best Management Practice(s)
CESCL Certified Erosion and Sediment Control Lead
CO2 Carbon Dioxide
CMP Corrugated Metal Pipe
CSWGP Construction Stormwater General Permit
CWA Clean Water Act
DMR Discharge Monitoring Report
DO Dissolved Oxygen
DOE Washington State Department of Ecology
EPA United States Environmental Protection Agency
ERTS Environmental Report Tracking System
ESC Erosion and Sediment Control
GULD General Use Level Designation
NPDES National Pollutant Discharge Elimination System
NTU Nephelometric Turbidity Units
NWRO Northwest Regional Office of the Department of Ecology
pH Power of Hydrogen
RCW Revised Code of Washington
SPCC Spill Prevention, Control, and Countermeasure
su Standard Units
SWMMWW Stormwater Management Manual for Western Washington
SWPPP Stormwater Pollution Prevention Plan
TESC Temporary Erosion and Sediment Control
TMDL Total Maximum Daily Load
WAC Washington Administrative Code
WDFW Washington Department of Fish and Wildlife
WSDOT
WWHM
Washington Department of Transportation
Western Washington Hydrology Model
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1. PROJECT INFORMATION
Project/Site Name: SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
Street/Location: SE 172nd Street and 125th Ave SE
City: Renton State: Washington Zip code: 98058
Receiving waterbody: Big Soos Creek
This Stormwater Pollution Prevention Plan (SWPPP) documents the sediment control and water quality
measures to be implemented during construction of the SE 172nd Street and 125th Ave SE GSI project,
to prevent sediment deposition into the Big Soos Creek as well as documenting proper implementation of
the temporary stream bypass to divert flows around the site during construction. The 13 elements of the
SWPPP, according to the Department of Ecology (DOE) and the associated best management practices
(BMPs) are documented in the following sections. A pre-construction meeting is required to address
these elements prior to beginning construction of the project.
The SWPPP is an active document that reflects the current conditions and changes throughout the life of
the project. Changes, formal or informal, should be documented in Appendix B. The SWPPP should be
updated when the Certified Erosion Control Lead (CESCL) has noted a deficiency in BMPs or deviation
from original design.
1.1 EXISTING SITE CONDITIONS
The project limits are approximately half a block (600 ft) north of SE 172nd St, on 122nd Ave SE, 123rd
Ave SE, 124th Ave SE, and 125th Ave SE (hereby referred to in this report as the north-south streets)
and approximately two blocks (1,400 ft) along SE 172nd St between 122nd Ave SE and 127th Ave SE.
Stormwater is collected and conveyed from parcels and ROW along SE 172nd St and west of 122nd Ave
SE into the existing storm system south of SE 172nd St via 12-inch concrete pipes up to the intersection
at 125th Ave SE. Stormwater from the north-south streets and offsite parcel areas is collected and
conveyed east through private parcels to 125th Ave SE through existing 18-inch concrete pipes, and then
south to connect to an existing catch basin at the intersection of 125th Ave SE and SE 172nd St that is
approximately 9 ft deep. Stormwater is then conveyed east in 24-inch concrete pipes along SE 172nd St to
the intersection on 127th Ave SE, where a 42-inch concrete pipe conveys runoff from east of SE 172nd St
and north of 127th Ave SE south to an existing wetland. The existing wetland is located south of the
intersection of 127th Ave SE and SE 172nd St.
There are known locations of flooding at the intersection of 127th Ave SE and SE 172nd St, and
improvements to existing conveyance system capacities is proposed in addition to providing water quality
retrofit benefits within the project limits.
The project discharges to “Wetland A”, which is a Category II depressional wetland with a habitat score of
6, buffer width of 100-feet and setback of 15-feet. There is also a “Wetland B” near the project area,
which is a Category III wetland with a habitat score of 4, buffer width of 50-feet and setback of 15-feet,
which is not impacted by the project. See Appendix G in Drainage Report for the wetland delineation
report.
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Table 1 presents a summary of suspected and/or known contaminants associated with the construction
of the project.
TABLE 1 | SUMMARY OF PROBABLE SITE POLLUTANT CONSTITUENTS
Constituent (pollutant) Location Depth Concentration
Vehicle fuels and lubricants 122nd Ave SE, 123rd Ave
SE, 124th Ave SE, 125th
Ave SE and SE 172nd Ave
Surface N/A
1.2 PROPOSED CONSTRUCTION ACTIVITIES
The project proposes to provide 20-foot driving lanes (10-foot on either side) of the existing roadway. The
project will provide 6 feet of parking on at least one side of all streets. A 6-foot landscape buffer is
proposed between the roadway and the proposed 5-foot sidewalk on one side of the street of each of the
streets within the project limits.
The project also proposes to collect flows from 122nd, 123rd, 124th and 125th Avenue SE into a
proposed conveyance system along SE 172nd Ave. Proposed stormwater facilities along the north-south
streets and SE 172nd Ave have been designed to collect runoff from a minimum of 2 acres of PGHS within
the project ROW via connections to proposed water quality treatment systems before discharging to the
wetland, south of SE 172nd St.
The project will include site preparation and installation of temporary erosion and sediment control
(TESC) measures, clearing and grubbing, excavation and grading, implementation of the storm water
pollution prevention plan, and site restoration following completion of construction. Final stabilization will
include restoring all disturbed areas within the project site.
1.2.1 CONSTRUCTION PHASING
Placeholder for final SWPPP based on more detailed phasing to be provided by Contractor.
1.2.2 CONSTRUCTION SCHEDULE
Construction is anticipated to begin in Spring 2023 and be completed by late-Summer 2023.
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2 CONSTRUCTION STORMWATER BEST MANAGEMENT
PRACTICES (BMPS)
To control on-site sediment, the following BMPs will be implemented prior to the beginning of construction
activities:
• High Visibility Silt Fence
• Inlet Protection
• Tree Protection/High Visibility Fence
These BMPs will be maintained throughout the project and will be inspected at regular intervals and
following significant storm events as required by the City of Renton and DOE rules and regulations. The
contractor will provide a maintenance and inspection plan that includes identification and contact
information for the ESC project lead and backup contacts.
Although every attempt has been made to identify appropriate BMPs at specific locations throughout the
project, situations will arise that require additional BMPs to be implemented. Therefore, erosion
prevention and sediment control materials are to be kept on the project site at all times to be used for
emergency situations, such as unexpected heavy summer rains. DOE’s BMP C150 lists recommended
materials and quantities to be kept on site. The construction manager shall verify that materials on hand
are in place prior to construction and regularly inventoried during construction.
The following sections outline the 13 elements required for a SWPPP according to the DOE Stormwater
Management Manual for Western Washington (SWMMWW) and the corresponding selected BMPs to be
installed at the project site during construction. All identified BMPs and BMPs shown on the plans are
minimum requirements based on the known conditions. Construction sites have ever changing conditions;
as a result, additional BMPs may have to be provided as deemed necessary by the CESCL.
2.1 ELEMENT 1: PRESERVE VEGETATION/MARK CLEARING LIMITS
Prior to beginning land disturbing activities, including clearing and grading, clearly mark all clearing limits,
sensitive areas and their buffers, and trees that are to be preserved within the construction area. These
shall be clearly marked, both in the field and on the plans, to prevent damage and offsite impacts.
Plastic, metal, or stake wire fence may be used to mark the clearing limits. The duff layer, native top soil,
and natural vegetation shall be retained in an undisturbed state to the maximum extent practicable. If it is
not practicable to retain the duff layer in place, it should be stockpiled on-site, covered to prevent erosion,
and replaced immediately upon completion of the ground disturbing activities.
Special consideration will be given to construction activities immediately adjacent to sensitive areas.
Stormwater conveyances and drainage ways will be given special consideration on this project so that all
construction personnel understand the requirement to prevent the degradation of water quality.
Selected BMPs for Element 1:
• BMP C101: Preserving Natural Vegetation
• BMP C102: Buffer Zones
• BMP C233: Silt Fence
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2.2 ELEMENT 2: ESTABLISH CONSTRUCTION ACCESS
Construction vehicles entering and exiting the project site will use only identified and approved access
points. Construction access points shall be determined by the contractor before the start of the project.
Approved construction access points will be marked on plans and in the field (as necessary) to prevent
unauthorized access and to limit further disturbance of environmental resources and surrounding
neighborhoods.
Sediment drag-out onto the street will be limited by effective implementation of construction road and
entrance stabilization measures to be installed per City of Renton or WSDOT Standard Plans. The
construction entrance will be stabilized with quarry spalls to reduce the amount of sediment transported
onto paved roads by vehicles or equipment. Only essential equipment will be allowed in the disturbed
areas and all equipment will be cleaned of loose sediment prior to moving offsite. Equipment will be
cleaned using brush and/or broom and, if necessary, wheel washing stations. The construction entrance
will be maintained as needed to prevent offsite transport of sediment.
If sediment is tracked off site, public roads shall be cleared thoroughly at the end of each workday, or
more frequently during wet weather, if necessary, to prevent sediment from entering waters of the state.
Sediment shall be removed from roads by manual shoveling and/or dry sweeping and the collected
sediments shall be transported to a controlled sediment disposal area. Use of water to wash down
surfaces will be prohibited unless specifically approved by the ESC Lead to assure turbid water is
appropriately managed and treated prior to discharge. Street wash wastewater shall be controlled by
pumping back on-site, or otherwise be prevented from discharging into systems tributary to state surface
waters. The contractor shall maintain all public roadways with street sweeping as necessary to remove
sediment.
Selected BMPs for Element 2:
• BMP C105: Stabilized Construction Entrance
• BMP C106: Wheel Wash
• BMP C107: Construction Road/Parking Area Stabilization
2.3 ELEMENT 3: CONTROL FLOW RATES
To protect properties and waterways downstream of the project site from erosion and the associated
discharge of turbid waters, stormwater discharges from the site will be controlled. No stormwater
infiltration or detention BMPs, permanent or temporary, shall be constructed at the project site.
Selected BMPs for Element 3:
• BMP233: Silt Fence
• BMP C235: Straw Wattles
2.4 ELEMENT 4: INSTALL SEDIMENT CONTROLS
To minimize the discharge of pollutants from the project, effective erosion and sediment control measures
are to be installed and maintained at the site. The depth to groundwater was observed at a depth of 4 to 6
feet below the surface, except at Boring EB-2 along 125th Street SE where groundwater was not
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observed to a depth of 11.5 feet. Due to the shallow groundwater table and small project limits, infiltration
BMPs are not feasible for the project.
Selected BMPs for Element 4:
• BMP C233: Silt Fence
• BMP C235: Straw Wattles
To avoid any potential sediment control issues, the project CESCL will immediately implement alternative
BMPs at the first sign that any of the existing BMPs are ineffective or failing.
2.5 ELEMENT 5: STABILIZE SOILS
Exposed and unworked soils will be protected with temporary seeding and mulching as well as plastic
sheeting over gravel or stockpiles over weekends or when rain is a possibility. Per DOE guidelines,
summarized in Table 2, no soils shall remain exposed and unworked for more than 7 days in the dry
season and more than 2 days during the wet season. The project is expected to be completed during the
dry season of 2023.
TABLE 2 | SOIL STABILIZATION REQUIREMENTS FOR THE WET AND DRY SEASON WEST OF THE CASCADE
MOUNTAIN CREST
Season Dates Number of Days Soils Can be Left Exposed
During the Dry Season May 1 – September 30 7 days
During the Wet Season October 1 – April 30 2 days
Soils must be stabilized at the end of the shift before a holiday or a weekend if needed based on the
weather forecast.
Selected BMPs for Element 5:
• BMP C120: Temporary and Permanent Seeding
• BMP C121: Mulching
• BMP C123: Plastic Covering
• BMP C125: Topsoiling/Composting
• BMP C140: Dust Control
2.6 ELEMENT 6: PROTECT SLOPES
Steep slopes are not present at the project site. Slopes from adjacent parcels shall be protected.
Selected BMPs for Element 6:
• BMP C120: Temporary and Permanent Seeding
• BMP C121: Mulching
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2.7 ELEMENT 7: PROTECT DRAIN INLETS
Inlet protection will be installed in the existing drain inlets within the work area prior to beginning any
clearing work.
Selected BMPs for Element 7:
• BMP C220: Inlet Protection
2.8 ELEMENT 8: STABILIZE CHANNELS AND OUTLETS
There are no channels and outlets to be stabilized at the project site.
2.9 ELEMENT 9: CONTROL POLLUTANTS
Maintenance, fueling, and/or repair of heavy equipment and vehicles is the only pollutant that is expected
to occur onsite. The contractor will be required to provide a final list of chemicals, fuels or oils that will be
on site. In addition, a security and containment plan will need to be approved and implemented prior to
bringing any chemicals, fuels or oils onto the site.
No pH-modifying sources are expected to be on-site during construction activities.
2.10 ELEMENT 10: CONTROL DE-WATERING
All sediment-laden water is required to be properly disposed of to prevent discharge to Waters of the
State. Proper disposal methods are summarized in Table 3.
TABLE 3 | DEWATERING BMPS
Infiltration
X Transport off-site in a vehicle (vacuum truck for legal disposal)
DOE-approved on-site chemical treatment or other suitable
treatment technologies
Sanitary or combined sewer discharge with local sewer district
approval (last resort)
X Use of sedimentation bag with discharge to ditch or swale
(small volumes of localized dewatering)
The contractor will be required to provide a dewatering plan that includes turbidity sampling. Inspection
and documentation will be completed at minimum intervals and after significant storms as required and
defined by the State or EPA rules and regulations. The maintenance and inspection plan, to be provided
by the contractor, will include identification, and contact information for the ESC project lead and backup
contacts. The contractor will identify a responsible person and City staff will provide oversight.
2.11 ELEMENT 11: MAINTAIN BMPS
All temporary and permanent Erosion and Sediment Control (ESC) BMPs shall be maintained and
repaired as needed to ensure continued performance of their intended function. Maintenance and repair
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shall be conducted in accordance with each particular BMP specification (see Volume II of the
SWMMWW).
Visual monitoring of all BMPs installed at the site will be conducted at least once every calendar week
and within 24 hours of any stormwater or non-stormwater discharge from the site. If the site becomes
inactive and is temporarily stabilized, the inspection frequency may be reduced to once every calendar
month.
All temporary ESC BMPs shall be removed within 30 days after final site stabilization is achieved or after
the temporary BMPs are no longer needed.
Trapped sediment shall be stabilized on-site or removed. Disturbed soil resulting from removal of either
BMPs or vegetation shall be permanently stabilized.
Additionally, protection must be provided for all BMPs installed for the permanent control of stormwater
from sediment and compaction. BMPs that are to remain in place following completion of construction
shall be examined and restored to full operating condition. If sediment enters these BMPs during
construction, the sediment shall be removed, and the facility shall be returned to conditions specified in
the construction documents.
Selected BMPs for Element 11:
• BMP C150: Materials on Hand
• BMP C160: Certified Erosion and Sediment Control Lead
2.12 ELEMENT 12: MANAGE THE PROJECT
The project will be managed based on the following principles:
• Projects will be phased to the maximum extent practicable and seasonal work limitations will be
taken into account.
• Inspection and monitoring:
o Inspection, maintenance and repair of all BMPs will occur as needed to ensure
performance of their intended function.
o Site inspections, monitoring, and sampling locations will be in accordance with the
Construction Stormwater General Permit (CSWGP).
o A CESCL shall be on-site or on-call at all times.
• Maintain an updated SWPPP.
o As site work progresses the SWPPP will be modified routinely to reflect changing site
conditions. The SWPPP will be reviewed monthly to ensure the content is current.
Applicable Management BMPs are identified in Table 4.
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TABLE 4 | MANAGEMENT BMPS
X Design the project to fit the existing topography, soils, and drainage patterns
X Emphasize erosion control rather than sediment control
X Minimize the extent and duration of the area exposed
X Keep runoff velocities low
Retain sediment on-site
X Thoroughly monitor site and maintain all ESC measures
X Schedule major earthwork during the dry season
Other (please describe)
A template for a phased BMP implementation schedule is provided in Table 5. This form shall be updated
and modified as the project progresses.
TABLE 5 | BMP IMPLEMENTATION SCHEDULE
Phase of Construction
Project Stormwater BMPs Date Wet/Dry
Season
Site Preparation BMPs C103 & 233 [MM/DD/YYY] Dry
[Insert construction activity] [Insert BMP] [MM/DD/YYY] [Insert season]
2.13 ELEMENT 13: PROTECT LOW IMPACT DEVELOPMENT (LID)
BMPS
Protect all LID BMPs including the proposed Filterra unit and Permeable Pavements from sedimentation
though installation and maintenance of erosion and sediment control BMPs on portions of the site that
drain into the LID BMPs. Restore the BMPs to their fully functioning condition if they accumulate sediment
during construction. Restoring the BMP must include removal of sediment and any sediment-laden
Bioretention soils, and replacing the removed soils with soils meeting the design specification.
Selected BMPs for Element 13:
• BMP C220: Inlet Protection
• BMP C233: Silt Fence
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3 POLLUTION PREVENTION TEAM
Table 6 is provided as a template for team member information and coordination as members are
identified.
TABLE 6 | TEAM INFORMATION
Title Name(s) Phone Number
Certified Erosion and Sediment
Control Lead (CESCL)
Provided by Contractor
[TBD]
[TBD]
Resident Engineer [TBD] [TBD]
Emergency DOE Contact [TBD] [TBD]
Emergency Permittee/ Owner Contact [TBD] [TBD]
Non-Emergency Owner Contact [TBD] [TBD]
Monitoring Personnel [TBD] [TBD]
DOE Regional Office Northwest Regional Office (425) 649-7000
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4 MONITORING AND SAMPLING REQUIREMENTS
Monitoring includes visual inspection, sampling for water quality parameters of concern, and
documentation of the inspection and sampling findings in a site log book. A site log book will be
maintained for all on-site construction activities and will include:
• A record of the implementation of the SWPPP and other permit requirements
• Site inspections
• Stormwater sampling data
A blank form is provided as a template in Appendix C.
The site log book must be maintained on-site within reasonable access to the site and be made available
upon request to DOE or the local jurisdiction.
4.1 SITE INSPECTION
Site inspections will be conducted at least once every calendar week and within 24 hours following any
discharge from the site. For sites that are temporarily stabilized and inactive, the required frequency is
reduced to once per calendar month.
The discharge point(s) are indicated on the Site Map (see Appendix A) and in accordance with the
applicable requirements of the CSWGP.
4.2 STORMWATER QUALITY SAMPLING
4.2.1 TURBIDITY SAMPLING
Requirements include calibrated turbidity meter or transparency tube to sample site discharges for
compliance with the CSWGP. Sampling will be conducted at all discharge points at least once per
calendar week.
Method for sampling turbidity:
TABLE 7 | TURBIDITY SAMPLING METHOD
Turbidity Meter/Turbidimeter (required for disturbances 5 acres or greater in size)
X Transparency Tube (option for disturbances less than 1 acre and up to 5 acres in size)
The benchmark for turbidity value is 25 nephelometric turbidity units (NTU) and a transparency less than
33 centimeters. If the discharge’s turbidity is 26 to 249 NTU or the transparency is less than 33 cm but
equal to or greater than 6 cm, the following steps will be conducted:
1. Review the SWPPP for compliance with Special Condition S9. Make appropriate revisions within
7 days of the date the discharge exceeded the benchmark.
2. Immediately begin the process to fully implement and maintain appropriate source control and/or
treatment BMPs as soon as possible. Address the problems within 10 days of the date the
discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible
within 10 days, DOE may approve additional time when the Permittee requests an extension
within the initial 10-day response period.
3. Document BMP implementation and maintenance in the site logbook.
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If the turbidity exceeds 250 NTU or the transparency is 6 cm or less at any time, the following steps will
be conducted:
1. Telephone or submit an electronic report to the applicable DOE Region’s Environmental Report
Tracking System (ERTS) within 24 hours. https://www.ecology.wa.gov/About-us/Get-
involved/Report-an-environmental-issue
• Northwest Region (King, Kitsap, Island, San Juan, Skagit, Snohomish, Whatcom): (425)
649-7000
2. Immediately begin the process to fully implement and maintain appropriate source control and/or
treatment BMPs as soon as possible. Address the problems within 10 days of the date the
discharge exceeded the benchmark. If installation of necessary treatment BMPs is not feasible
within 10 days, DOE may approve additional time when the Permittee requests an extension
within the initial 10-day response period.
3. Document BMP implementation and maintenance in the site logbook.
4. Continue to sample discharges daily until one of the following is true:
• Turbidity is 25 NTU (or lower).
• Transparency is 33 cm (or greater).
• Compliance with the water quality limit for turbidity is achieved.
o 1 - 5 NTU over background turbidity, if background is less than 50 NTU
o 1% - 10% over background turbidity, if background is 50 NTU or greater
• The discharge stops or is eliminated.
4.2.2 PH SAMPLING
Monitoring for pH may be required for cast-in-place concrete work.
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5 DISCHARGES TO 303(D) OR TOTAL MAXIMUM DAILY
LOAD (TMDL) WATERBODIES
5.1 303(D) LISTED WATERBODIES
Ecology has classified the upstream of Big Soos Creek as a Category 4C water that is impaired by a non-
pollutant. The Big Soos Creek is impaired by causes that cannot be addressed through a TMDL plan.
Impairments in the creek include low water flow, stream channelization, and dams.
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6 REPORTING AND RECORD KEEPING
6.1 RECORD KEEPING
6.1.1 SITE LOG BOOK
A site log book will be maintained for all on-site construction activities and will include:
• A record of the implementation of the SWPPP and other permit requirements
• Site inspections
• Sample logs
6.1.2 RECORDS RETENTION
Records will be retained during the life of the project and for a minimum of three (3) years following the
termination of permit coverage in accordance with Special Condition S5.C of the CSWGP.
Permit documentation to be retained on-site:
• CSWGP
• Permit Coverage Letter
• SWPPP
• Site Log Book
Permit documentation will be provided within 14 days of receipt of a written request from DOE. A copy of
the SWPPP or access to the SWPPP will be provided to the public when requested in writing in
accordance with Special Condition S5.G.2.b of the CSWGP.
6.1.3 UPDATING THE SWPPP
The SWPPP will be modified if:
• Found ineffective in eliminating or significantly minimizing pollutants in stormwater discharges
from the site.
• There is a change in design, construction, operation, or maintenance at the construction site that
has, or could have, a significant effect on the discharge of pollutants to waters of the State.
The SWPPP will be modified within seven (7) days if inspection(s) or investigation(s) determine additional
or modified BMPs are necessary for compliance. An updated timeline for BMP implementation will be
prepared.
6.2 REPORTING
6.2.1 DISCHARGE MONITORING REPORTS
Cumulative soil disturbance is one (1) acre or larger; therefore, Discharge Monitoring Reports
(DMRs) will be submitted to Ecology monthly. If there was no discharge during a given monitoring period
the DMR will be submitted as required reporting “No Discharge”. The DMR due date is fifteen (15) days
following the end of each calendar month.
DMRs will be reported online through Ecology WQWebDMR System.
CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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https://ecology.wa.gov/Regulations-Permits/Guidance-technical-assistance/Water-quality-permits-
guidance/WQWebPortal-guidance
6.2.2 NOTIFICATION OF NONCOMPLIANCE
If any of the terms and conditions of the permit is not met, and the resulting noncompliance may cause a
threat to human health or the environment, the following actions will be taken:
1. DOE will be notified within 24-hours of the failure to comply by calling the applicable Regional
office ERTS phone number (Regional office numbers listed below).
2. Immediate action will be taken to prevent the discharge/pollution or otherwise stop or correct the
noncompliance. If applicable, sampling and analysis of any noncompliance will be repeated
immediately and the results submitted to DOE within five (5) days of becoming aware of the
violation.
3. A detailed written report describing the noncompliance will be submitted to DOE within five (5)
days, unless requested earlier by DOE.
Anytime turbidity sampling indicates turbidity is 250 NTUs or greater, or water transparency is 6 cm or
less, the DOE Regional office will be notified by phone within 24 hours of analysis as required by Special
Condition S5.A of the CSWGP.
• Northwest Region at (425) 649-7000 for Island, King, Kitsap, San Juan, Skagit, Snohomish, or
Whatcom County
Include the following information:
1. Your name and / Phone number
2. Permit number
3. City / County of project
4. Sample results
5. Date / Time of call
6. Date / Time of sample
7. Project name
In accordance with Special Condition S4.D.5.b of the CSWGP, the DOE Regional office will be notified if
chemical treatment other than CO2 sparging is planned for adjustment of high pH water.
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APPENDIX A – SITE MAP
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SWPPP – Appendix A
SE 172nd STREET AND 125th AVENUE SE
GREEN STORMWATER INFRASTRUCTURE PROJECT
SWP-27-4037
PROJECT LOCATION MAP
CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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APPENDIX B – CORRESPONDENCE
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CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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This storm water pollution prevention plan (SWPPP) should be revised and updated to address changes
in site conditions, new or revised government regulations, and additional on-site storm water pollution
controls.
All revisions to the SWPPP must be documented on the SWPPP Revision Documentation Form, which
should include the information shown below. The authorized facility representative who approves the
SWPPP should be an individual at or near the top of the facility’s management organization, such as the
president, vice president, construction manager, site supervisor, or environmental manager. The
signature of this representative attests that the SWPPP revision information is true and accurate. All
SWPPP revisions will either be drafted or approved by the City of Redmond.
SWPPP Revision Documentation Form
Number Date Author
Company
Representative
Signature
0
1
2
3
4
5
6
7
8
9
10
CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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APPENDIX C – SITE INSPECTION FORM
Construction Stormwater Site Inspection Form
Page 1
Project Name Inspection Date Time
Name of Certified Erosion Sediment Control Lead (CESCL) or qualified inspector if less than one acre
Print Name:
Approximate rainfall amount since the last inspection (in inches):
Approximate rainfall amount in the last 24 hours (in inches):
Current Weather Clear Cloudy Mist Rain Wind Fog
A.Type of inspection:Weekly Post Storm Event Other
B. Phase of Active Construction (check all that apply):
Pre Construction/installation of erosion/sediment
controls
Clearing/Demo/Grading Infrastructure/storm/roads
Concrete pours Vertical
Construction/buildings
Utilities
Offsite improvements Site temporary stabilized Final stabilization
Yes No
Yes No
Yes No
r Yes No
Yes No
C.Questions:
1.Were all areas of construction and discharge points inspected?
2.Did you observe the presence of suspended sediment, turbidity, discoloration, or oil sheen
3.Was a water quality sample taken during inspection?
4.Was there a turbid discharge 250 NTU or greate to an infiltration facility?
5.If yes to #4 was it reported to Ecology?
6.Is pH sampling required? pH range required is 6.5 to 8.5.Yes No
If answering yes to a discharge, describe the event. Include when, where, and why it happened; what action was taken,
and when.
*If answering yes to # 4 record NTU with continual sampling daily until turbidity is 25 NTU or less.
Sampling Results: Date:
Parameter Method (circle one) Result Other/Note
NTU pH
Turbidity tube, meter, laboratory
pH Paper, kit, meter
Construction Stormwater Site Inspection Form
Page 2
D. Check the observed status of all items. Provide “Action Required “details and dates.
Element # Inspection BMPs
Inspected
BMP needs
maintenance
BMP
failed
Action
required
(describe in
section F)
yes no n/a
1
Clearing
Limits
Before beginning land disturbing
activities are all clearing limits,
natural resource areas (streams,
wetlands, buffers, trees) protected
with barriers or similar BMPs? (high
visibility recommended)
2
Construction
Access
Construction access is stabilized
with quarry spalls or equivalent
BMP to prevent sediment from
being tracked onto roads?
Sediment tracked onto the road
way was cleaned thoroughly at the
end of the day or more frequent as
necessary.
3
Control Flow
Rates
Are flow control measures installed
to control stormwater volumes and
velocity during construction and do
they protect downstream
properties and waterways from
erosion?
If permanent infiltration ponds are
used for flow control during
construction, are they protected
from siltation?
4
Sediment
Controls
All perimeter sediment controls
(e.g. silt fence, wattles, compost
socks, berms, etc.) installed, and
maintained in accordance with the
Stormwater Pollution Prevention
Plan (SWPPP).
Sediment control BMPs (sediment
ponds, traps, filters etc.) have been
constructed and functional as the
first step of grading.
Stormwater runoff from disturbed
areas is directed to sediment
removal BMP.
5
Stabilize
Soils
Have exposed un-worked soils
been stabilized with effective BMP
to prevent erosion and sediment
deposition?
Construction Stormwater Site Inspection Form
Page 3
Element # Inspection BMPs
Inspected
BMP needs
maintenance
BMP
failed
Action
required
(describe in
section F)
yes no n/a
5
Stabilize Soils
Cont.
Are stockpiles stabilized from erosion,
protected with sediment trapping
measures and located away from drain
inlet, waterways, and drainage
channels?
Have soils been stabilized at the end of
the shift, before a holiday or weekend
if needed based on the weather
forecast?
6
Protect
Slopes
Has stormwater and ground water
been diverted away from slopes and
disturbed areas with interceptor dikes,
pipes and or swales?
Is off-site storm water managed
separately from stormwater generated
on the site?
Is excavated material placed on uphill
side of trenches consistent with safety
and space considerations?
Have check dams been placed at
regular intervals within constructed
channels that are cut down a slope?
7
Drain Inlets
Storm drain inlets made operable
during construction are protected.
Are existing storm drains within the
influence of the project protected?
8
Stabilize
Channel and
Outlets
Have all on-site conveyance channels
been designed, constructed and
stabilized to prevent erosion from
expected peak flows?
Is stabilization, including armoring
material, adequate to prevent erosion
of outlets, adjacent stream banks,
slopes and downstream conveyance
systems?
9
Control
Pollutants
Are waste materials and demolition
debris handled and disposed of to
prevent contamination of stormwater?
Has cover been provided for all
chemicals, liquid products, petroleum
products, and other material?
Has secondary containment been
provided capable of containing 110%
of the volume?
Were contaminated surfaces cleaned
immediately after a spill incident?
Were BMPs used to prevent
contamination of stormwater by a pH
modifying sources?
Construction Stormwater Site Inspection Form
Page 4
Element # Inspection BMPs
Inspected
BMP needs
maintenance
BMP
failed
Action
required
(describe in
section F)
yes no n/a
9
Cont.
Wheel wash wastewater is handled
and disposed of properly.
10
Control
Dewatering
Concrete washout in designated areas.
No washout or excess concrete on the
ground.
Dewatering has been done to an
approved source and in compliance
with the SWPPP.
Were there any clean non turbid
dewatering discharges?
11
Maintain
BMP
Are all temporary and permanent
erosion and sediment control BMPs
maintained to perform as intended?
12
Manage the
Project
Has the project been phased to the
maximum degree practicable?
Has regular inspection, monitoring and
maintenance been performed as
required by the permit?
Has the SWPPP been updated,
implemented and records maintained?
13
Protect LID
Is all Bioretention and Rain Garden
Facilities protected from
sedimentation with appropriate BMPs?
Is the Bioretention and Rain Garden
protected against over compaction of
construction equipment and foot
traffic to retain its infiltration
capabilities?
Permeable pavements are clean and
free of sediment and sediment laden-
water runoff. Muddy construction
equipment has not been on the base
material or pavement.
Have soiled permeable pavements
been cleaned of sediments and pass
infiltration test as required by
stormwater manual methodology?
Heavy equipment has been kept off
existing soils under LID facilities to
retain infiltration rate.
E. Check all areas that have been inspected.
All in place BMPs All disturbed soils All concrete wash out area All material storage areas
All discharge locations All equipment storage areas All construction entrances/exits
Construction Stormwater Site Inspection Form
Page 5
F. Elements checked “Action Required” (section D) describe corrective action to be taken. List the element number;
be specific on location and work needed. Document, initial, and date when the corrective action has been completed
and inspected.
Element
#
Description and Location Action Required Completion
Date
Initials
Attach additional page if needed
Sign the following certification:
“I certify that this report is true, accurate, and complete, to the best of my knowledge and belief”
Inspected by: (print) (Signature) Date:
Title/Qualification of Inspector:
CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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APPENDIX D – CONSTRUCTION STORMWATER GENERAL
PERMIT (CSWGP)
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CITY OF RENTON SE 172ND STREET AND 125TH AVENUE SE GSI PROJECT
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APPENDIX E – CONTAMINATED SITE INFORMATION
AS NEEDED.
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APPENDIX F – ENGINEERING CALCULATIONS
AS NEEDED.
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APPENDIX G – GEOTECHNICAL ENGINEERING REPORT
Provided under separate cover.