HomeMy WebLinkAboutApplication Applicant 8/29/2023August 25, 2023
Tom Seivers
Senior Planner
City of Springfield
225 West 5^ Street
Springfield, OR 97477
RE: Case Number 811-23-000043-TYP1
Response to Staff Report and Decision
Tom:
Thank you for your thorough staff report. The following are the responses to the Type 1 Site Plan Review
—Multiple Unit Housing Application. The City items are in regular typeface and my responses are in
italics.
Conditions of Approval
1. Prior to approval of the Final Site Plan, the applicant must show that the two existing unused
driveway entrances and sidewalk on Marcola Road are to be removed and full height curb restored.
See note added to Site Plan.
2. Prior to approval of the Final Site Plan, the applicant will submit a final drainage report with all
calculations and devices determined as final.
Please we attached Preliminary Stormwater Report — updated August 2023.
3. Prior to approval of the Final Site Plan, the applicant must submit a vegetation plan for the proposed
stormwater planters per the infiltration planter details in Appendix B of the City of Eugene stormwater
management manual and Chapter 6 of the EDSPM. The planting/layout plan must also use the same
terminology as used in the Operations and Maintenance agreement conditioned below.
See attached Planting Plan Sheets L1.0, L2.0 and L3.0
4. Prior to approval of the Final Site Plan, the applicant shall submit a specific water quality manhole
that meets the State of Washington's TAPE list for pretreatment requirements.
See attached Sheet EXH-1 Water treatment Details.
5. Prior to approval of the final site plan, the applicant must provide an operations and maintenance plan
to the City for review to ensure the long-term maintenance and operation of the proposed stormwater
planters and water quality manhole, consistent with maintenance criteria required by EDSMP 3.03.1.
The plan must designate maintenance responsibility for operating and maintaining the system and
must be distributed to all property owners and tenants of the site. The manufacturers specific
requirements for the water quality manhole must be supplied to meet this requirement.
See attached O&M Report.
6. Prior to approval of the final site plan, the applicant must show a cross section of the stormwater
treatment facilities on the final site plan with at least 24" of planting medium in them (the normal
requirement is 12" of planting medium).
See attached Sheet EXH-1 Water treatment Details.
7. To ensure a fully functioning water quality system and meet objectives of Springfield's MS4 permit,
the Springfield Development Code and the EDSPM, the proposed stormwater planters must be fully
vegetated with all vegetation species established prior to approval of final site inspection.
Alternatively, if this condition cannot be met, the applicant must provide and maintain additional
interim erosion control/water quality measures acceptable to the public works department that will
suffice until such time as the wale vegetation becomes fully established.
Acknowledged.
Schirmer Consulting, LLC • PO Box 10424, Eugene, OR 97440 • (541) 234-5109
Land.ape NMitedure ♦ Land Use Planning
Paradigm Marcda Apartments Page 2 of 2
Case Number 811-23-000043-TYP1 - Response to conditions of Approval
Auaud 25, 2023
8. Prior to approval of the Final Site Plan, the applicant must showthe location of thewelI, if it still exists,
and indicate whether it will be used or if it will be decommissioned. If it is to be decommissioned, it
must be done prior to construction.
Efforts were made to locate the well through records search, etc. No well was found either in the
records or on the survey.
9. Prior to approval of the Final Site Plan, the 'Type B' lighting along the street frontages must be
modified to prevent excessive light spillover into the rights-of-way by eliminating or rearranging the
Type B lighting scheme, or by replacing them with wall pack lighting where possible.
See attached revised Lighting Plan showing wall pack lighting along street frontages to prevent
excessive light spillover.
10. As part of the building permit application the applicant must apply for and obtain an encroachment
permit for the storm drain connection
Acknowledged.
Please call if you have any questions, comments or need any additional information. I believe this
completes all conditions of approval.
Sincerely,
Schirmer Consulting, LLC
Carol Schirmer
Schirmer Con.1ing, LLC • PO Box 10424, Eugene, OR 97440 • (541) 234-5108
Landscape A & tedure ♦ Land Use Planning
August 25, 2023
Tom Seivers
Senior Planner
City of Springfield
225 West 5^ Street
Springfield, OR 97477
RE: Case Number 811-23-000043-TYP1
Response to Staff Report and Decision
Tom:
Thank you for your thorough staff report. The following are the responses to the Type 1 Site Plan Review
—Multiple Unit Housing Application. The City items are in regular typeface and my responses are in
italics.
Conditions of Approval
1. Prior to approval of the Final Site Plan, the applicant must show that the two existing unused
driveway entrances and sidewalk on Marcola Road are to be removed and full height curb restored.
See note added to Site Plan.
2. Prior to approval of the Final Site Plan, the applicant will submit a final drainage report with all
calculations and devices determined as final.
Please we attached Preliminary Stormwater Report — updated August 2023.
3. Prior to approval of the Final Site Plan, the applicant must submit a vegetation plan for the proposed
stormwater planters per the infiltration planter details in Appendix B of the City of Eugene stormwater
management manual and Chapter 6 of the EDSPM. The planting/layout plan must also use the same
terminology as used in the Operations and Maintenance agreement conditioned below.
See attached Planting Plan Sheets L1.0, L2.0 and L3.0
4. Prior to approval of the Final Site Plan, the applicant shall submit a specific water quality manhole
that meets the State of Washington's TAPE list for pretreatment requirements.
See attached Sheet EXH-1 Water treatment Details.
5. Prior to approval of the final site plan, the applicant must provide an operations and maintenance plan
to the City for review to ensure the long-term maintenance and operation of the proposed stormwater
planters and water quality manhole, consistent with maintenance criteria required by EDSMP 3.03.1.
The plan must designate maintenance responsibility for operating and maintaining the system and
must be distributed to all property owners and tenants of the site. The manufacturers specific
requirements for the water quality manhole must be supplied to meet this requirement.
See attached O&M Report.
6. Prior to approval of the final site plan, the applicant must show a cross section of the stormwater
treatment facilities on the final site plan with at least 24" of planting medium in them (the normal
requirement is 12" of planting medium).
See attached Sheet EXH-1 Water treatment Details.
7. To ensure a fully functioning water quality system and meet objectives of Springfield's MS4 permit,
the Springfield Development Code and the EDSPM, the proposed stormwater planters must be fully
vegetated with all vegetation species established prior to approval of final site inspection.
Alternatively, if this condition cannot be met, the applicant must provide and maintain additional
interim erosion control/water quality measures acceptable to the public works department that will
suffice until such time as the wale vegetation becomes fully established.
Acknowledged.
Schirmer Consulting, LLC • PO Box 10424, Eugene, OR 97440 • (541) 234-5109
Land.ape NMitedure ♦ Land Use Planning
Paradigm Marcda Apartments Page 2 of 2
Case Number 811-23-000043-TYP1 - Response to conditions of Approval
Auaud 25, 2023
8. Prior to approval of the Final Site Plan, the applicant must showthe location of thewelI, if it still exists,
and indicate whether it will be used or if it will be decommissioned. If it is to be decommissioned, it
must be done prior to construction.
Efforts were made to locate the well through records search, etc. No well was found either in the
records or on the survey.
9. Prior to approval of the Final Site Plan, the 'Type B' lighting along the street frontages must be
modified to prevent excessive light spillover into the rights-of-way by eliminating or rearranging the
Type B lighting scheme, or by replacing them with wall pack lighting where possible.
See attached revised Lighting Plan showing wall pack lighting along street frontages to prevent
excessive light spillover.
10. As part of the building permit application the applicant must apply for and obtain an encroachment
permit for the storm drain connection
Acknowledged.
Please call if you have any questions, comments or need any additional information. I believe this
completes all conditions of approval.
Sincerely,
Schirmer Consulting, LLC
Carol Schirmer
Schirmer Con.1ing, LLC • PO Box 10424, Eugene, OR 97440 • (541) 234-5108
Landscape A & tedure ♦ Land Use Planning
Operations & Maintenance Plan
Paradigm Marcola Apartments
In order for the stormwater treatment facilities to continue operating at acceptable levels, regular
maintenance and inspection are required. This plan provides maintenance and inspection
instructions. The Operations and Maintenance Plan shall be recorded with Lane County.
Prepared for: Dustrud Architecture
Prepared by: Ranch Rondeau, EIT
Project Engineer: Matt Keenan, PE
August 2023 1 KPFF Project #2200316
KPFF'S COMMITMENT TO SUSTAINABILITY
As a member of the US Green Building Council,
a sustaining member of Oregon Natural Step,
and a member of the Sustainable Products
Purchasers Coalition, KPFF is committed to the
practice of sustainable design and the use of
sustainable materials in our work.
When hardcopy reports are provided by KPFF,
they are prepared using recycled and recyclable
materials, reflecting KPFF's commitment to
using sustainable practices and methods in all
of our products.
Table of Contents
Responsibility
Schedule ...............................
Procedure .............................
Stormwater Planter........
Swales............................
Water Quality Manhole.
Inlets, Drains and Basins
Piped Storm System .......
Appendices
Appendix 1
Facility Operations and Maintenance Plan: Stormwater Planter
Appendix 2
Facility Operations and Maintenance Plan: Swales
Appendix 3
Facility Operations and Maintenance Plan: Water Quality Manhole
Appendix 4
Notice of Operations and Maintenance Plan
Appendix 5
Form 0&M: Operations and Maintenance Plan
Appendix 6
Facility Inspection and Maintenance Log
PARADIGMMARCOLIAPAUMENTS I KPFFComulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Responsibility
The facility is to be maintained by the property owner. The preparer has designed a system that can be easily
maintained by the maintenance staff.
A copy of the Operations and Maintenance (O&M) Plan shall be provided to all property owners and
managers.
Descriptions
The Stormwater System collects and treats runoff from pollution -generating surfaces within the site as
required by the City of Springfield.
All runoff from the vehicular impervious surfaces at Paradigm Marcola Apartments site will be treated by a
combination of vegetated treatment facilities and a water quality manhole.
Definitions
• Stormwater Planters are walled vegetated surface reservoirs used to collect and treat stormwater
runoff from impervious surfaces by allowing pollutants to settle and filter out as the water
percolates through the vegetation and soil mediums before infiltrating into the ground below or
being piped to its downstream destination.
• Swales are long and narrow vegetated and grassed depressions used to collect, detain and convey
stormwater runoff, allowing pollutants to settle and filter out as the water flows through the
facility.
• A Water quality Manhole is a mechanical treatment device intended to remove debris and oils
from the stormwater before it enters the system.
• Growing Media is a specialty soil containing little to no fines designed to filter stormwater reliably
without clogging. In the event that the planter soil needs to be replaced, it must be replaced with
soil that matches the building's plans and specifications.
• An Overflow Inlet is a vertical pipe with an atrium grate over it that allows stormwater from large
rain events to bypass treatment and enter the downstream storm system. The grate prevents
debris and rodents from entering the piped storm system. The domed nature of the grate
discourages clogging at the inlet.
Schedule
The whole system shall be inspected and maintained annually and within 48 hours after each major storm
event. For this 0&M plan, a major storm event is defined as 2 inches of rain in 24 hours or more. All
components of the storm system as described on the next page must be inspected and maintained
frequently, or they will cease to function effectively. The facility owner must keep a log recording all
inspection dates, observations and maintenance activities. Receipts shall be saved when maintenance is
performed so there is a record of all expenses.
PARADIGMMARCOLIAPAUMENT I KPFFComulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Procedure
Stormwater Planter
• See Appendix 1 for the required maintenance procedure.
Swales
• See Appendix 2 for the required maintenance procedure.
Water Quality Manhole
• See Appendix 3 for the required maintenance procedure.
Inlets, Drains and Basins
• Shall be inspected for obstructions, debris, oil and grease, which shall be removed upon discovery.
• If water ponds over the inlet for more than two hours after a major storm, the inlet drain may be
clogged.
• Check for debris/sediment accumulation in and around the inlet or overflow, rake and remove
upland causes (erosion, surface debris, etc.).
Piped Storm System
• Annual inspection for clogging shall be performed.
• Shall be inspected for cracks or leaks during each inspection.
• Cleaning shall be done without the use of detergents or surfactants. A pressure washer may be
used if necessary.
220031s -kg
PARADIGMMARCOLIAPAUMENTS I KPFFCPmulting Engineers 3
OPERATIONS AND MAINTENANCE PIAN
Appendix 1
Facility Operations and Maintenance Plan: Stormwater Planter
PARADIGM MARCOLI APARTMENTS I KPFF CPmulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Stormwater Planters
Operations and Maintenance Plan
Stormwater Planters are designed to allow runoff to filter through layers of topsoil (thus capturing
pollutants) and then either infiltrate into the native soils (infiltration planter) or be collected in a pipe to be
discharged off-site (flow-through planter). The planter is sized to accept runoff and temporarily store the
water in a reservoir on top of the soil. The flow-through planter is designed with an impervious bottom or
is placed on an impervious surface. Water should drain through the planter within 3A hours after a storm
event. All facility components and vegetation shall be inspected for proper operations and structural
stability. These inspections shall occur, at a minimum, quarterly for the first 2 years from the date of
installation, 2 times per year thereafter, and within 48 hours after each major storm event. The facility
owner must keep a log, recording all inspection dates, observations, and maintenance activities. The
following items shall be inspected and maintained as stated:
Downspout from rooftop or sheet flow from paving allows unimpeded storrnwater flow to the planter.
• Debris shall be removed routinely (e.g., no less than every 6 months) and upon discovery.
• Damaged pipe shall be repaired upon discovery.
Splash Blocks prevent splashing against adjacent structures and convey water without disrupting media.
• Any deficiencies in structure such as cracking, rolling, and failure shall be repaired.
Planter Reservoir receives and detains storm water prior to infiltration. Water should drain from
reservoir within 3-4 hours of storm event.
• Sources of clogging shall be identified and corrected to prevent short circuiting.
• Topsoil may need to be amended with sand or replaced all together to achieve a satisfactory
infiltration rate.
Filter Media consisting of sand, gravel and topsoil shall allow stormwater to percolate uniformly through
the planter. The planter shall be excavated and cleaned, and gravel or soil shall be replaced to correct low
infiltration rates.
• Holes that are not consistent with the design and allow water to flow directly through the planter to
the ground shall be plugged.
• Sediment accumulation shall be hand removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 4 inches thick or so thick as to
damage or kill vegetation.
• Litter and debris shall be removed routinely (e.g., no less thanquarterly) and upon discovery.
Planter shall contain filter media and vegetation.
• Structural deficiencies in the planter including rot, cracks, and failure shall be repaired.
Overflow Pipe safely conveys flow exceeding reservoir capacity to an approved stormwater receiving
system
• Overflow pipe shall be cleared of sediment and debris when 50% of the conveyance capacity is
plugged.
• Damaged pipe shall be repaired or replaced upon discovery.
Vegetation shall be healthy and dense enough to provide filtering while protecting underlying soils from
erosion.
• Mulch shall be replenished at least annually.
• Vegetation, large shrubs or trees that limit access or interfere with planter operation shall be primed or
removed.
• Fallen leaves and debris from deciduous plant foliage shall be raked and removed if build up is
damaging vegetation.
• Nuisance or prohibited vegetation shall be removed when discovered. Invasive vegetation
contributing up to 25% of vegetation of all species shall be removed and replaced.
• Dead vegetation shall be removed to maintain less than 10% of area coverage or when planter
function is impaired. Vegetation shall be replaced within a specific timeframe, e.g., 3 months, or
immedia[el if re aired to maintain cover densityand control erosion where soils are expose
Debris and Litter shall be removed to ensure stormwater infiltration and to prevent clogging of overflow
Section I - Chapter 3 Page 24 of 41 EDSP Adopted December 03, 2012
Appendix 3A Submittal Packet WO Information
drains and interference with plant growth.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining stormwater planters shall
be provided to all property owners and tenants. A copy of the O&M Plan shall be provided to all property
owners and tenants.
Access to the stormwater planter shall be safe and efficient. Egress and ingress routes shall be maintained
to design standards. Roadways shall be maintained to accommodate size and weight of vehicles, if
applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the stormwater planter shall
be removed.
• Gravel or ground cover shall be added if erosion occurs, e.g., due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the stormwater planter. Pest control measures shall be
taken when insects/rodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors, the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non -chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector. Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non -chemical methods have proved unsuccessful, contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thurengensis var. israchensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the stormwater planter shall be filled and cora acted.
Section I - Chapter 3 Page 25 of 41 EDSP Adopted December 03, 2012
Appendix 3A Submittal Packet WO Information
Appendix 2
Facility Operations and Maintenance Plan: Swales
PARADIGM MARCOLI APARTMENTS I KPFF CPmulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Swales (Vegetated, Grassy and Street)
Operations and Maintenance Plan
Swales are vegetated or grassed open channels that trap pollutants by filtering and slowing flows,
allowing particles to settle out. The swale should drain within 48 hours of a stone event. All facility
components, vegetation, and source controls shall be inspected for proper operations and structural
stability, at a minimum, quarterly for the first 2 years from the date of installation, 2 times per year
thereafter, and within 48 hours after each maj or storm event. The facility owner must keep a log,
recording all inspection dates, observations, and maintenance activities. The following items shall be
inspected and maintained as stated:
Swale Inlet (such as curb cuts or pipes) shall maintain a calm flow of water entering the swale.
• Source of erosion shall be identified and controlled when native soil is exposed or erosion channels
are forming.
• Sediment accumulation shall be hand -removed with minimum damage to vegetation using proper
erosion control measures. Sediment shall be removed if it is more than 3" thick or so thick as to
damage or kill vegetation.
• hilet shall be cleared when conveyance capacity is plugged. Sources of sediment and debris shall be
identified and corrected.
• Rocks lash pads, spreaders and dissipaters shall be replenished to prevent erosion.
Side Slopes shall be maintained to prevent erosion that introduces sediment into the swale.
• Slopes shall be stabilized and planted using appropriate erosion control measures when native soil is
exposed or erosion channels are forming.
Swale Media shall allow stormwater to percolate uniformly through the landscape swale. If the swale
does not drain within 48 hours, it shall be tilled and replanted according to design specifications.
• Swale area shall be protected during construction from compaction.
• Annual or semi-annual tilling shall be implemented if compaction or clogging continues.
• Debris in quantities that inhibit operation shall be removed routinely (e.g., no less than quarterly), or
upon discovery.
Swale Outlet shall maintain sheet flow of water exiting swale unless a collection drain is used. Source of
erosion damage shall be identified and controlled when native soil is exposed or erosion channels are
forming.
• Outlets such as drains and overland flow paths shall be cleared when 50% of the conveyance capacity
is plugged.
• Outlet structures shall be cleaned of sediment and debris at least 1 time per year or when the level is
at 50% of the conveyance capacity.
• Sources of sediment and debris shall be identified and corrected.
Vegetation shall be healthy and dense enough to provide filtering while protecting underlying soils from
erosion. Mulch shall be replenished as needed to ensure survival of vegetation.
• Vegetation, large shrubs or trees that interfere with landscape swale operation shall be pnumd.
• Fallen leaves and debris from deciduous plant foliage shall be removed if build up is damaging
vegetation.
• Grassy swales shall be mowed to keep grass 4" to 9" in height. Clippings shall be removed when
possible, to remove pollutants absorbed in grasses, or when build up is damaging vegetation.
• Nuisance and prohibited vegetation (such as blackberries and English Ivy) shall be removed when
discovered. Invasive vegetation contributing up to 25% of vegetation of all species shall be removed
and replaced.
• Dead vegetation and woody material shall be removed to maintain less than 10% of area coverage or
when swale function is impaired. Vegetation shall be replaced within 3 months, or immediately if
require to maintain cover density and control erosion where soils are exposed.
Debris and Litter shall be removed to ensure stormwater conveyance and to prevent clogging of inlet
and outlet drains and interference with plant growth.
Spill Prevention measures shall be exercised when handling substances that contaminate stormwater.
Section I - Chapter 3 Page 18 of 41 EDSP Adopted December 03, 2012
Appendix 3A Submittal Packet WO Information
Releases of pollutants shall be corrected as soon as identified.
Training and/or written guidance information for operating and maintaining swales shall be provided
to all property owners and tenants. A copy of the O&M Plan shall be provided to all property owners and
tenants.
Access to the swale shall be safe and efficient. Egress and ingress routes shall be maintained to design
standards. Roadways shall be maintained to accommodate size and weight of vehicles, if applicable.
• Obstacles preventing maintenance personnel and/or equipment access to the swale shall be removed.
• Gravel or ground cover shall be added if erosion occurs, e.g., due to vehicular or pedestrian traffic.
Insects and Rodents shall not be harbored in the swale. Pest control measures shall be taken when
insectstrodents are found to be present.
• If a complaint is received or an inspection reveals that a stormwater facility is significantly infested
with mosquitoes or other vectors, the property owner/owners or their designee may be required to
eliminate the infestation at the City inspector's discretion. Control of the infestation shall be
attempted by using first non -chemical methods and secondly, only those chemical methods
specifically approved by the City's inspector. Acceptable methods include but are not limited to the
following:
i. Installation of predacious bird or bat nesting boxes.
ii. Alterations of pond water levels approximately every four days in order to disrupt mosquito larval
development cycles.
iii. Stocking ponds and other permanent water facilities with fish or other predatory species.
iv. If non -chemical methods have proved unsuccessful, contact the City inspector prior to use of
chemical methods such as the mosquito larvicides Bacillus thmengensis var. israchensis or other
approved larvicides. These materials may only be used with City inspector approval if evidence
can be provided that these materials will not migrate off-site or enter the public stormwater
system. Chemical larvicides shall be applied by a licensed individual or contractor.
• Holes in the ground located in and around the swale shall be filled.
If used at this site, the following will be applicable:
Check Dams, flow spreaders and dissipaters shall control and distribute flow.
• Causes for altered water flow or short circuits shall be identified, and obstructions cleared upon
discovery.
• Causes for channelization shall be identified and repaired.
• Systems shall remain free of sediment build up and debris.
Section I - Chapter 3 Page 19 of 41 EDSP Adopted December 03, 2012
Appendix 3A Submittal Packet WO Information
Appendix 3
Facility Operations and Maintenance Plan: Water Quality Manhole
PARADIGM MARCOLI APARTMENTS I KPFF CPmulting Engineers
OPERATIONS AND MAINTENANCE PIAN
C=::NTECH®
ENGINEERED SOLUTIONS
Stormceptor° STC
Operation and Maintenance Guide
Stormceptor®
Stormceptor Design Notes
Only the STC 4501 is adaptable to function with a catch basin inlet and/or inline pipes.
Only the Stormceptor models STC 4501 to STC 7200 may accommodate multiple inlet pipes.
Inlet and outlet invert elevation differences are as follows:
Inlet and Outlet Pipe Invert Elevations Differences
Inlet Pipe Configuration STC 4501
STC 900 to STC 7200 STC 11000 to STC 16000
Single inlet pipe 3 in. (75 mm)
1 in. (25 mm) 3 in. (75 mm)
Multiple inlet pipes 3 in. (75 mm)
3 in. (75 mm) Only one inlet pipe.
Maximum inlet and outlet pipe diameters:
Inlet/Outlet Configuration
Inlet Unit
In -Line Unit
series"
STC 4501
STC 900 to STC 7200
STC 11000 to STC 16000
Straight Through
24 inch (600 mm)
42 inch (1050 mm)
60 inch 0500 mm)
Bend (90 degrees)
18 inch (450 mm)
33 inch (825 mrr�
33 inch (825 mm)
The inlet and in-line Stormceptor units can accommodate turns to a maximum of 90 degrees.
Minimum distance from top of grade to crown is 2 feet (0.6 m)
Submerged conditions. A unit is submerged when the standing water elevation at the proposed location of the Stormceptor
unit is greater than the outlet invert elevation dud ng zero flow conditions. In these cases, please contact your local Stormceptor
representative and provide the following information:
Top of grade elevation
Stormceptor inlet and outlet pipe diameters and invert elevations
Standing water elevation
Stormceptor head loss, K = 1.3 (for submerged condition, K = 4)
2 Stormceptore Operation and Maintenance Guide
Stormceptor®
OPERATION AND MAINTENANCE GUIDE
Table of Content
1. AboutStonmceptor
2. Sto.ceptor Design
4
4
3. Key Operation Features ................................................................................................................................................................
6
4. Stonrnoeptor Product Line .............................................................................................................................................................
7
S. Sizing the Sto"ceptor System...................................................................................................................................................
10
6. Spill Controls ..............................................................................................................................................................................
12
7. Sto"ceptor Options ..................................................................................................................................................................
14
S. Comparing Technologies ............................................................................................................................................................
17
9. TeAinq ........................................................................................................................................................................................
is
10. Installation ................................................................................................................................................................................. IS
11. StonrnceptorConstruction Sequence .......................................................................................................................................... IS
12. Maintenance.............................................................................................................................................................................. 19
Ston-nceptore0perafion and Maintenance Guide 3
1. About Stormceptor
The Storroceptor® STC (Standard Treatment Cell) was developed by Imbrium'" Systems to address the growing need to remove and isolate
pollution from the storm drain system before it enters the environment The Stormceptor STC target hydrocarbons and total suspended
solids (TSS) in sto.ter mnoff. It improves water quality by removing contaminant through the gravitational settling of fine sediment
and floatation of hydrocarbons while preventing the re -suspension or scour of previously captured pollutant.
The development of the Stormceptor STC revolutionized storrmNater treatment, and created an entirely new category of environmental
technology. Protecting thousands of waterways around the word, the Stormceptor System has set the standard for effective storrmwater
treatment
1.1. Patent Information
The Stormceptor technology is protected by the following patent:
• Australia Patent No. 693,164 • 693,164 • 707,133 • 729,096 • 779401
• Austrian Patent No. 289647
• Canadian Patent No 2,009,208 •2,137,942 • 2,175,277 • 2,180,305 • 2,180,383 • 2,206,338 • 2,327,768 (Pending)
• China Patent No 1168439
• Denmark DK 711879
• German DE 69534021
• Indonesian Patent No 16688
• Japan Patent No 9-11476 (Pending)
• Korea 10-2000-0026101 (Pending)
• Malaysia Patent No PI9701737 (Pending)
• New Zealand Patent No 314646
• United States Patent No 4,985,148 • 5,498,331 • 5,725,760 • 5,753,115 • 5,849,181 • 6,068,765 • 6,371,690
• Stormceptor OSR Patent Pending • Stormceptor LCS Patent Pending
2. Stormceptor Design Overview
2.1. Design Philosophy
The patented Stormceptor System has been designed to focus on the environmental objec five of providing long-term pollution control. The
unique and innovative Storrmeptor design allows for continuous positive treatment of runoff during all rainfall event, while ensuring that
all captured pollutant are retained within the system, even during intense storm event.
An integral part of the Stormceptor design is PCSWMM for Stormceptor - sizing software developed in conjunction with Computational
Hydraulics Inc. (CHI) and intern atonally acclaimed expert, Dc Bill James. Using local historical rainfall data and con tinuoussimulation
modeling, this software allows a Stormceptor unit to be designed for each individual site and the corresponding water quality objectives.
By using PCSWMM for Stormceptor, the Stormceptor System can be designed to remove a wide range of particles (typically from 20 to
2,000 morons), and can also be customized to remove a specific particle size distribution (PSD). The specified PSD should accurately reflect
what is in the stormwater runoff to ensure the device is achieving the desired water quality objective. Since storrmNater mnoff contains small
particles (less than 75 microns), it is important to design a treatment system to remove smaller particles in addition to coarse particles.
4 Stom,eptor®Operafion and Maintenance Guide
2.2. Benefits
The Stormceptor System removes free oil and suspended solids from stormvJater, prevenfing spills and non -point source pollufion from
enedng downstream lakes and rivers. The key benefits, capabilifies and applications of the Stormceptor System are as follows:
Provides con fin rout positive treatment during all rainfall events
Can be designed to remove over 80% of the annual sediment load
Removes a wide range of parficles
Can be designed to remove specific parficle size distribution (PSD)
Captures free oil from stormweter
Prevent scouring or re -suspension of trapped pollutants
Pre-treatment to reduce maintenance costs for downstream treatment measures (ponds, swales, detenfion basins, filters)
Groundwater recharge protecfion
Spills capture and mifigation
Simple to design and specify
Designed to your local watershed condifions
Small footprint to allow for easy retrofit installations
Easy to maintain (vacuum tuck)
Multiple inlet can connect to a single unit
Suitable as a bend structure
Pre-engineered for traffic loading (minimum AASHTO HS -20)
Minimal elevation drop between inlet and outlet pipes
Small head loss
Addifional protection provided by an 18" (457 mm) fiberglass skirt below the top of the insert, for the containment of hydrocarbons
in the event of a spill.
2.3. Environmental Benefit
Freshwater resources are vital to the health and welfare of their surrounding communities. There is increasing public awareness, government
regulators and corporate commitment to reducing the pollufion entering our waterways. A major source of this pollufion originates from
stomiwamr runoff from urban areas. Rainfall runoff carnes oils, sediment and other contaminant from roads and parking lot discharging
directly into oursteams, lakes and coastal waterways.
The Stormceptor System is designed to isolate comarrinant from getting into the natural environment The Stormceptor technology
provides protecfion for the environment from spills that occur at service stators and vehicle accident sit=s, while also removing
contaminated sediment in runoff that washes from mads and parking lot.
Sto mceptor® Operafion and Maintenance Guide 5
3. Key Operation Features
3.1. Scour Prevention
A key feature of the Stormceptor System is its patented scour prevention technology. This innovation ensures pollutants are captured and
retained during all rainfall event, even extreme storms. The Stormceptor System provides con finuous posi five treatrnent for all rainfall
event, including intense storms. Stormceptorslows incoming runoff, controlling and reducing velocities in the lower chamber to create a
non -turbulent environment that promotes free oils and floatable debris to rise and sediment to settle.
The patented scour prevention technology, the fiberglass insert, regulates flows into the lower chamber through a combination of a weir
and orifice while diverting high energy flows away through the upper chamber to prevent scouring. Laboratory testing demonstrated no
scouring when tested up to 125% of the unit's operating rat!, with the unit loaded to 100%sedimentcapacity(NJ DEP, 2005). Second,
the depth of the lower chamber ensures the sedimentstorage zone is adequatAy separated from the path of flow in the lower chamber to
preventscouring.
3.2. Operational Hydraulic Loading Rate
Designers and regulators need to evaluate the treatment capacity and performance of manufactured stomiwater treatment systems. A
commonly used parameter is the "operational hydraulic loading rate" which originated as a design methodology for wastewater treatment
devices.
Operafional hydraulic loading rate may be calculated by dividing the flow rate into a device by it settling area. This represents the critical
settling velocity that is the prime determinant to quanfify the influent particle size and density captured by the device. PCSW MM for
StomKeptor uses a similar parameter that is calculated by dividing the hydraulic detention time in the device by the fall distance of the
sediment
v,c H = Q
6x As
Where:
v, = critical settling velocity, ft/s (rNs)
H = tank depth, ft (m)
0x = hydraulic detention time, ft/s(rrys)
Q = volumetric flow rate, ft3/s (m3/s)
A, = surface area, ft' (m')
(Tchobanoglous, G. and Schroeder, E.D. 1987. Water Quality. Addison Wesley.)
Unlike designing typical wastewater devices, story warier systems are designed for highly variable flow rates including intense peak
flows. PCSWMM for Stormceptor incorporates all of the flows into it calculations, ensuring that the operational hydraulic loading rate is
considered not only for one flow rate, but for all flows including extreme events.
3.3. Double Wall Containment
The Stormceptor System was conceived as a pollution identifier to assist with idenfifying illicit discharges. The fiberglass insert has
a con finuous skirt that lines the concrete barrel wall for a depth of 18 inches (457 mm) that provides double wall containment for
hydrocarbons storage. This protective barrier ensures that toxic floatables do not mgrate through the concrete wall into the surrounding
soils.
6 Stommceptor®Operafion and Maintenance Guide
4. Stormceptor Product Line
4.1. Stormceptor Models
A summary of Stormceptor models and capacities are listed in Table 1.
Table 1. Stormceptor Models
Stormceptor Model
STC 4501
Total storage Volume
U.S. Gal (L)
470 (1,780)
Hydrocarbon Storage
Capacity U.S. Gal (L)
86 (330)
Ma)dmum Sediment
Capacity W (L)
46 (1,302)
STC 900
952 (3,600)
251 (950)
89 (2,520)
STC 1200
1,234 (4,670)
251 (950)
127(3,596)
STC 1800
1,833 (6,940)
251 (950)
207 (5,861)
STC 2400
2,462 (9,320)
840 (3,180)
205 (5,805)
STC 3600
3,715 (1,406)
840(3,180)
373(10,562)
STC 4800
5,059 (1,950)
909(3,440)
543(15,376)
STC 6000
6,136 (23,230)
909(3,440)
687(19,453)
STC 7200
7,420 (28,090)
1,059 (4,010)
839 (23,757)
STC 11000
11,194(42,370)
2,797 (10, 590)
1,086 (30,752)
STC 13000
13,348 (50,530)
2,797 (10, 590)
1,374 (38,907)
STC 16000
15,918 (60,260)
3,055 (11, 560)
1,677 (47,487)
NOTE: Storage volumes may vary slightly from region to region. For detailed information, contactyour local Stormceptor mpreseutative.
4.2. Inline Stormceptor
The Inline Stormceptor, Figure 1, is the standard design for most stormwater treatment applications. The patented Stormceptor design
allows the Inline unit to maintain continuous positive treahneut of total suspended solids (TSS) yea,mund, regardless of flow rate. The Inline
Stormceptor is composed of a precast concrete tank with a fiberglass insert situated at the invert of the storm sewer pipe, creating an upper
chamber above the insert and a lower chamber below the insert.
Stormceptor° Operation and Maintenance Guide 7
Figure 1. Inline Stormceptor
Operation
As water flows into the Stormceptor unit, it is slowed and directed to the lower chamber by a weir and drop tee. The stomiwater enters the
lower chamber, a non -turbulent environment, allowing free oils to rise and sediment to settle. The oil is captured underneath the fiberglass
insert and shielded from exposure to the concrete walls by a fiberglass skirt After the pollutants separate, treated water confinues up a riser
pipe, and exits the lower chamber on the downstream side of the weir before leaving the unit During high flow events, the Stormceptor
System's patented scour prevention technology ensures confinuous pollutant removal and prevents re -suspension of previously captured
Pollutants.
8 Stormceptor° Opeafion and Maintenance Guide
Figure 2. Inlet Stormceptor
4.3. Inlet Stormceptor
The Inlet Stormceptor System, Figure 2, was designed to provide protection for parking lots, loading bays, gas stations and other spill -prone
areas. The Inlet Stormceptor is designed to remove sediment from sto.ater introduced through a grated inlet, a stormsevrer pipe, or
both.
The Inlet Stormceptor design operates in the same manner as the Inline unit, providing continuous positive treatment, and ensuring that
captured material is not re -suspended.
4.4. Series Stormceptor
Designed to treat larger drainage areas, the Series Stormceptor System, Figure 3, consist of tvvo adjacent Stormceptor models that function
in parallel. This design eliminates the need for additional structures and piping to reduce installation cost.
Stormceptor° Operation and Main tenance Guide 9
Figure 3. Series System
The Series Stormceptor design operates in the same manner as the Inline unit, providing continuous positive treatment, and ensuring that
captured material is not re -suspended.
5. Sizing the Stormceptor System
The Stormceptor System is a versatile product that can be used for many different aspect of water quality improvement While addressing
these needs, there are conditions that the designer needs to be aware of in order to size the Stormceptor model to meet the demands of
each individual site in an efficient and cost-effective manner.
PCSWMM for Stormceptor is the support tool used for identifying the appmpriate Stormceptor model. In order to size a unit, it is
recommended the user follow the seven design steps in the program. The steps are as follows:
STEP 1 — Project Details
The firststep prior to sizing the Stormceptor System is to clearly identify, the water quality objective for the development Itis recommended
hate level of annual sediment (TSS) re.val be identified and defined by a particle size distribution.
STEP 2 — Site Details
Identify, the site development by the drainage area and the level of imperviousness. Itis recommended that imperviousness be calculated
based on the actual area of imperviousness based on paved surfaces, sidewalks and rooftops.
STEP 3 — Upstream Attenuation
The Stormceptor System is designed as a water quality device and is sometimes used in conjunction with onsite water quanfity control
devices such as ponds or underground detention systems. When possible, a greater benefit is typically achieved when installing a
Stormceptor unit upstream of a detention facility. By placing the Stormceptor unit upstream of a detention structure, a benefit of less
maintenance of the detention facility is realized.
10 Stormceptor° Operation and Main tenance Guide
STEP 4 — Particle Size Distribution
It is critical that the PSD be defined as part of the water quality objective. PSD is crifical for the design of treatmentsystem for a unit process
of gravity settling and governs the size of a treatment system. A range of particle sizes has been provided and it is recommended that clays
and silt -sized particles be considered in addition to sand and gravel -sized particles. Options and sample PSDB are provided in PCSWMM for
Stormceptor. The default particle size distribution is the Fine Distribution, Table 2, option.
Table 2. Fine Distribution
20
20%
1.3
60
20%
1.8
150
20%
2.2
400
20%
2.65
2000
20%
2.65
If the objective is the long-term removal of 80% of the total suspended solids on a given site, the PSD should be representative of the
expected sediment on the site. For example, a system designed to remove 80% of coarse particles (greater than 75 microns) would provide
relatively poor removal efficiency of finer particles that may be naturally prevalent in runoff from the site.
Since the small particle fraction contributes a disproportionately large amount of the total available particle surface area for pollutant
adsomfion, a system designed primarily for coarse particle capture will compromise water quality objectives.
STEP 5 — Rainfall Records
Local historical rainfall has been acquired from the U.S. National Oceanic and Atmospheric Administration, Environment Canada and
regulatory agencies across North America. The rainfall data provided with PCSMM for Stormceptor provides an accurate estimation of small
storm hydrology by modeling actual historical storm events including duration, intensities and peaks.
STEP 6 — Summary
At this point, the program may be executed to predict the level of TSS removal from the site. Once the simulation has completed, a table
shall be generated identifying the TSS removal of each Stormceptor unit
STEP 7 — Sizing Summary
Performance estimates of all Stormceptor units for the given site parameters will be displayed in a tabular format The unit that meets the
water quality objective, identified in Step 1, will be highlighted.
Stormceptor° Operation and Maintenance Guide 11
5.1. PCSWMM for Stormceptor
The Stormceptor System has been developed in conjunction with PCSWMM for Stormceptor as a technological solution to achieve water
quality goals. Together, these two innovations model, simulate, predict and calculate the water quality objectives desired by a design
engineerfor TSS removal.
PCSWMM for Stormceptor is a proprietarysizing program which uses sitespecific inputs m a computer model m simulatesediment
accumulation, hydrology and long-term total suspended solids removal. The model has been calibrated to field monitoring result from
Stormceptor unit that have been monitored in North America. The sizing methodology can be described by three processes:
1. Determination of real time hydrology
2. Buildup and wash off of TSS from impervious land areas
I TSS transport through the Stormceptor (settling and discharge). The use of a calibrated model is the preferred method for sizing
stormwater quality structures for the following reasons:
• The hydrology of the local area is properly and accurately incorporated in the sizing (distribution of flows, flow rate ranges and
peaks, back-to-backstorms, inter -event times)
• The distribution of TSS with the hydrology is properly and accurately considered in the sizing
• Particle size distribution is properly considered in the sizing
n The sizing can be optimized for TSS removal
• The cost benefit of alternate TSS removal criteria can be easily assessed
• The program assesses the performance of all Stormceptor models. Sizing may be selected based on a specific water quality
outcome or based on the Maximum Fxtent Practicable
For more information regarding PCSWMM for Stormceptor, contactyour local Stormceptor representative, or visitwww.imbriumayst!ms.com
to download a free copy of the program.
5.2. Sediment Loading Characteristics
The way in which sediment is transferred to stormwarter can have a considerable effect on which type of system is implemented. On typical
impervious surfaces (e.g. parking lot) sediment will build over time and wash off with the next rainfall. When rainfall patterns are examned,
a short intense storm will have a higher concentration of sediment than a long slow drizzle. Together with rainfall data representing the site's
typical rainfall patterns, sediment loading characteristics playa part in the correct sizing of a stormwater quality device.
Typical Sites
For standard site design of the Stormceptor System, PCSWMM for Stormceptor is utilized to accurately assess the unit's performance. As
an integral part of the product's design, the program can be used to meet local requirement for total suspended solid removal. Typical
installations of manufactured stormwater treatment devices would occur on areas such as paved parking lot or paved mads. These are
considered "stable" surfaces which have non — erodible surfaces.
Unstable Sites
While standard sites consist of stable concrete or asphalt surfaces, sites such as gravel parking lot, or maintenance yards with stockpiles
of sediment would be classified as "unstable". These types of sit=s do not exhibit first flush characteristics, are highly erodible and exhibit
atypical sediment loading characteristics and must therefore be sized more carefully. Contact your local Stormceptor representative for
assistance in selecting a proper unit sized for such unstable sites.
6. Spill Controls
When considering the removal of total petroleum hydrocarbons (TPH) from a storm sewersystem there are two functions of the system: oil
removal, and spill capture.
'Oil Removal' describes the capture of the minute volumes of free oil mobilized from impervious surfaces. In this instance relatively low
concentrations, volumes and flow rates are considered. While the Stormceptor unitwill All provide an appreciable oil removal function
during higher flow event and/or with higher TPH concentrations, desired effluent limit may be exceeded under these conditions.
12 Stormceptor® Operation and Maintenance Guide
'Spill Capture' describes a manner of TPH removal morn_ appropriate to recovery of a relatively high volume of a single phase deleterious
liquid that is introduced to the storm sewer system over a mla dvely short dum don. The two design criteria involved when considering this
manner of introduction are overall volume and the specific gravity of the material. A standard Stormceptor unit will be able to capture and
retain a maximum spill volume and a minimum specific gravity.
For spill characteristics that fall outside these limits, unit modifications are required. Contact your local Stormceptor Representative for more
information.
One of the key features of the Stormceptor technology is its ability to capture and retain spills. While the standard Stormceptor System
provides excellent protection for spill control, there are additional options to enhance spill protection if desired.
6.1. Oil Level Alarm
The oil level alarm is an electronic monitoring system designed to trigger visual and audible alarm when a pre-set level of oil is reached
within the lower chamber. As a standard, the oil
level alarm is designed to trigger at approximately 85% of the unit's available depth level for oil capture. The feature acts as a safeguard
against spills caused by exceeding the oil storage capacity of the separator and elirrinates the need for manual oil level inspection.
The oil level alarm installed on the Stormceptor insert is illustrated in Figure 4.
Figure 4. Oil level alarm
6.2. Increased Volume Storage Capacity
The Stormceptor unit maybe modified to store a greater spill volume than is typically available. Under such a scenario, instead of installing
a larger than required unit, modifications can be made to the recommended Stormceptor model to accommodate Iargervolumes. Contact
your local Stormceptor representative for additional information and assistance for modifications.
Stormceptor° Operation and Maintenance Guide 13
7. Stormceptor Options
The Stormceptor System allover flexibility min corporate to exisfin g and new storm drainage infrastructure. The following section idenfifies
considerefions that should be reviewed when installing the system into a drainage network. For con difions that fall outside of the
recommendafions in this section, please contact your local Stormceptor representa five for further guidance.
7.1. Installation Depth Minimum Cover
The minimum distance from the top of grade to the crown of the inlet pipe is 24 inches (600 mm). For situations that have a lovver
minimum distance, contact your local Stormceptor representative.
7.2. Maximum Inlet and Outlet Pipe Diameters
Maximum inlet and outlet pipe diameters are illustrated in Figure 5. Contact your local Stormceptor representative for larger pipe diameters
Upper
Maximum Pipe Diameters for Straight Through and 90° Bends
Chamber
(Based on Concrete Pipe)
Diameter
24 inch 24 inch
(000 mm) (600 mm)
18 inch
1450M
Inlet
Stormceptor
t
18 inch
450mm)
42 inch 42inch
33 inch
(1050 mm) (1050 mm)
(825 mm)
Inline
Stormceptor
+
33 inch
(825 mm)
Inline
1 60 Inch
(500 mm) p6mmm)
42 inch
Stormceptor
(1050 mm)
or
+
Series
42 rch
Stormceptor
(1050mm)
Figure 5. Maximum pipe diameters for straight through and bend applications
"The bend should only be incorporated into the second structure (downstream structure) of the
Series Stormceptor System
7.3. Bends
The Stormceptor System can be used to change horizontal alignment in the storm drain network up to a maximum of 90 degrees. Figure
6 illustrates the typical bend situafions of the Stormceptor System Bends should only be applied to the second structure (downstream
stmcwre) of the Series Stormceptor System.
14 Stdnmceptrrr®Cpeafion and Maintenance Guide
Stormceptor
System
Maximum Bend Configurations
so°
Inlet StormceptorOutlet
Pipe
Inlet Pipe }
so°
Inline
Stormceptor
Inial PipeOutlet Pipe
0�9G-
Outlet Pipe
90°
$efIDS
Inlet Pipe
_ _
Stormceptor
} }
so°
Upstream Unit Downstream Unit
Figure 6. Maximum bend angles
7.4. Multiple Inlet Pipes
The Inlet and Inline Stormceptor System can accommodate two or more inlet pipes. The maximum number of inlet pipes that can be
accommodated into a Stormceptcr unit is a function of the number, alignment and diameter of the pipes and it effects on the structural
integrity of the precast concrete. When multiple inlet pipes amused for new development, each inlet pipe shall have an invertelevation 3
inches (75 mm) higher than the outlet pipe invert elevation.
7.5. Inlet/Outlet Pipe Invert Elevations
Recommended inlet and outlet pipe invert differences are listed in Table 3.
Table 3. Recommended Drops Between Inlet and Outlet Pipe Inverts
1 3 inches (75 mm) 1 inch (25 mm) 3 inches (75 mm)
> 1 3 inches (75 mrrd 3 inches (75 mm) Not Aoolicable
7.6. Shallow Stormceptor
In cases where there may be restrictions to the depth of burial of storm sewer systems. In this situation, for selected Stormceptor models,
the lower chamber component may be increased in diameter to reduce the overall depth of excavation required.
7.7. Customized Live Load
The Stormceptcrsystem is typically designed for local highway truck loading (AASHTO HS- 20). When the project requires live loads
greater than HS -20, the Stormoa r System may be customized structurally for a pre -specified live load. Contact your local Stormceptor
representative for cuswrrized loading conditions.
Stormceptor° Operation and Maintenance Guide 15
7.8. Pre-treatment
The Stormceptor System maybe sized to remove sediment and for spills control in conjunction with other stormwater PMPs to meet the
water quality objective. For pretreatment applications, the Stormceptor System should be the first unit in a treatment train. The benefit of
pre-treatment include the extension of the operational life (extension of maintenance frequency) of large stormwater management facilities,
prevention of spills and lower total life- cycle maintenance cost.
7.9. Head loss
The head loss through the Stormceptor System is similar to a 60 degree bend at a manhole. The K value for calculating minor losses is
approximately 1.3 (minor loss = k* 1.3v2/2g).
However, when a Submerged modification is applied to a Stormceptor unit, the corresponding Kvalue is 4.
7.10. Submerged
The Submerged modification, Figure 7, allows the Stormceptor System to operate in submerged or partially submerged storm sewers. This
configuration can be installed on all models of the Stormceptor System by modifying the fiberglass insert. A customized weir height and a
secondarydrop tee are added.
Submerged instances are defined as standing water in the storm drain system during zero flow conditions. In these instances, the following
information is necessary for the proper design and application of submerged modifications:
• Stormceptor top of grade elevation
• Stormceptor outlet pipe invert elevation
• Standing waterelevation
Figure 7. Submerged Stormceptor
16 Strrrmceptrrr® Operation and Main tenance Guide
S. Comparing Technologies
Designers have many choices available to achieve water quality goals in the treatment of stormwater runoff. Since many altematives am
available for use in sto.ter quality treatment it is important to consider how to make an appropriate comparison between "a ppmved
altem a Hives". The following is a guide to assistwith the accurate comparison of differing technologies and performance claims.
8.1. Particle Size Distribution (PSD)
The most sensitive parameter to the design of a stormwater quality device is the selection of the design particle size. While itis
recommended that the actual particle size distribution (PSD) for sites be measured poor to sizing, alternative values for particle size should
be selected to represent what is likely to occur naturally on the sim. A reasonable estimateof a particle size distribution likely to be found
on parking lots or other impervious surfaces should consist of a wide range of particles such as 20 micronsto 2,000 microns (Ontario MOE,
1994).
Thereis no absolute right particle size distribution or specific gravity and the user is cautioned to review the site location, characteristics,
material handling practices and regulatoryrequirements when selecting a particlesize distribution. When comparing technologies, designs
using different PSDB will resultin incomparable TSS removal efficiencies. The PSD of the TSS removed needs to bestandard between two
pmductato allow for an accuratecomparison.
8.2. Scour Prevention
In order to accurately predict the performance of a manufactured treatment device, there must be confidence that it will perform under all
conditions. Since rainfall pattems cannot be predicted, stormwater quality devices placed in storm sewer systems must be able m vdthstand
extreme events, and ensure that all pollutants previously captured are retained in the system.
In order to have confidence in a system's performance under extreme conditions, independent validation of scour prevention is essential
when examining differenttechnologies. Lack of independentvedfication of scour prevention should make a designerwary of accepting any
product's performance claims.
8.3. Hydraulics
Full scale laboratory testing has been used to confirm the hydraulics of the Stormceptor System. Result of lab testing have been used to
physically design the Stormceptor Systemand thesewerpipes entering and leaving the unit. Key benefit of Stormceptor are:
• Low head loss (typical k value of 1.3)
• Minimal inlet/outlet invert elevation drop across the structure
• Use as a bend structure
• Accommodates multiple inlets
The adaptability of the treatment device to the storm sewer design infrastructure can affect the overall performance and cost of the site.
8.4. Hydrology
Stomiwater quality treatment technologies need to perform under varying climatic conditions. These can vary from long low intensity rainfall
m shortduration, high intensitystrums. Since a treatment device is expected to perform under all these conditions, it makes sense that any
system's design should accommodate those conditions as well.
Long-term continuous simulation evaluates the performance of a technology under the varying conditions expected in the climate of the
subject site. Single, peak event design does not provide this information and is not equivalent to long-term simulation. Designers should
request long-term simulation performance to ensure the technology can meet the long-term water quality objective.
Stormceptor° Operation and Maintenance Guide 17
9. Testing
The Stormceptor System has been the most widely monitored stormwater tmatment technology in the world. Performance verification and
monitoring programs am completed to the strictest standards and integrity. Since it introduction in 1990, numerous independent field tests
and studies detailing the effectiveness of the Stormceptor System have been completed.
• Coventry University, UK-97%removal of oil, 83% removal of sand and 73% removal of peat
• National Water Resea¢h Institute, Canada, -scaled testing for the development of the Stormceptor System identifying both TSS
removal and scour prevention.
• New Jersey TARP Program- full scale testing of an STC 900 demonstrating 75% TSS removal of particles from 1 to 1000 microns. Scour
testing completed demonstrated that the system does notscour. The New Jersey Departrnent of Envirocr ctal Protection was followed.
• City of Indianapolis- full scale testing of an STC 900 demonstrating over 80% TSS removal of particles from 50 microns to 300 microns
at 130% of the unit's operating rate. Scour testing completed demonstrated that the system does not scour.
• Westwood Massachusetts(1997), demonstrated 80% TSS removal
• Como Park (1997), demonstrated 76% TSS removal
• Ontario MOE SWAMP Program- 57% removal of 1 to 25 micron particles
• Laval Quebec- 50% removal of 1 to 25 micron particles
10. Installation
The installation of the concrete Stormceptor should conform in general to state highway, or local specifications for the installation of
manholes. Selected sections of a general specification that are applicable are summarized in the following sections.
10.1. Excavation
Excavation for the installation of the Stormceptor should conform to state highway, or local specifications. Topsoil removed during the
excavation for the Stormceptorshould be stockpiled in designated areas and should not be mixed with subsoil or other materials.
Topsoil stockpiles and the general site preparation for the installation of the Stormceptor should conform to state highway or local
specifications.
The Stormceptorshould not be installed on frozen ground. Excavation should extend a minimum of 12 inches (300 mrr� from the precast
concrete surfaces plus an allowance forshoring and bracing where required. If the bottom of the excavation provides an unsuitable
foundation additional excavation may be required.
In areas with a high water table, continuous dewatering may be required to ensure that the excavation is stable and free of water.
10.2. Backfilling
Backfill material should conform to state highway or local specifications. Backfill material should be placed in uniform layers not exceeding
12 inches (300mm) in depth and compacted to state highway or local specifications.
11. Stormceptor Construction Sequence
The concreteStormceptor is installed in sections in the following sequence:
1. Aggregate base
2. Base slab
3. Lower chamber sections
4. Upper chamber section with fiberglass insert
5. Connect inlet and outlet pipes
6. Assembly of fiberglass insert components (drop me, riser pipe, oil cleanout portand orifice plate
7. Remainder of upper chamber
8. Frame and access cover
The precast base should be placed level at the specified grade. The entire base should be in contact with the underlying compacted granular
material. Subsequent sections, complete with joint seals, should be installed in accordance with the precast concrete manufacturer's
recommendations.
18 Stor oeptor®Opemfion and Maintenance Guide
Adjustment of the Stormceptor can be performed by liffing the upper sections free of the excavated area, re -leveling the base and re-
installing the sections. Damaged sections and gaskets should be repaired or replaced as necessary. Once the Stormceptor has been
constructed, any lift holes must be plugged with mortar.
12. Maintenance
12.1. Health and Safety
The Stormceptor System has been designed considering safety first It is recommended that confined space entry protocols be followed if
entry to the unit is required. In addition, the fiberglass insert has the following health and safety features:
Designed to withstand the weight of personnel
A safety grate is located over the 24 inch (600 mm) riser pipe opening
Ladder rungs can be provided for entry into the unit, if required
12.2. Maintenance Procedures
Maintenance of the Stormceptorsystem is performed using vacuum trucks. No entry into the unit is required forma interance (in most
cases). The vacuum service industry is a well- established sector of the service industry that cleans underground tanks, sewers and catch
basins. Costs to clean a Stormceptorvdll vary based on the size of unit and transportation distances.
The need for maintenance can be determined easily by inspecting the unit from the surface. The depth of oil in the unit can be determined
by inserting a dipstick in the oil inspection/cleanout port.
Sirrilarly, the depth of sediment can be measured from the surface without entry into the Stormceptor via a dipstick tube equipped with
a ball valve. This tube would be inserted through the riser pipe. Maintenance should be performed once the sediment depth exceeds the
guideline values provided in the Table 4.
Table 4. Sediment Depths Indicating Required Servicing*
Model
Sediment Depth inches(mm)
4501
8(200)
900
8 (200)
1200
10(250)
1800
15(381)
2400
12(300)
3600
17(430)
4800
15(380)
6000
18(460)
7200
15(381)
11000
17(380)
13000
20(500)
16000
17(380)
* based on 15% of the Stormceptor un iPs total storage
Although annual servicing is recommended, the frequency of maintenance may need to be increased or reduced based on local conditions
(i.e. if the unit is filing up with sediment more quickly than projected, maintenance may be required semi-annually; conversely once the site
has stabilized maintenance may only be required every two or three years).
Oil is removed through the oil inspection/cleanout port and sediment is removed through the riser pipe. A tem afively oil could be removed
from the 24 inches (600 mm) opening if water is removed from the lower chamber to lower the oil level below the drop pipes.
The following procedures should be taken when cleaning out Stormceptor.
1. Check for oil through the oil cleanout port
2. Remove any oil separately using a small portable pump
3. Decant the water from the unit to the sanitary sewer, if permitted by the local regulating authority, or into a separate containment tank
4. Remove the sludge from the bottom of the unit using the vacuum truck
5. Re -fill Stormceptorwith water where required by the local jurisdiction
Stormceptor° Operation and Maintenance Guide 19
12.3. Submerged Stormceptor
Careful attention should be paid m maintenance of the Submerged Stormceptor System. In cases where the storm drain system is
submerged, there is a requirement m plug both the inlet and outlet pipes to economically clean out the unit
12.4. Hydrocarbon Spills
The Stormceptor is often installed in areas where the potential for spills is great. The Stormceptor System should be cleaned immediately
after a spill occurs by a licensed liquid waste hauler.
12.5. Disposal
Requirements for the disposal of material from the Stormceptor System are similar m that of any other shhrmwater Best Management
Practice (BMP) where permitted. Disposal options for the sediment may range from disposal in a sanitary trunk sewer upstream of a sewage
treatment plank m disposal in a sanitary landfill site. Petroleum waste products collected in the Stormcephhr(free oil/chemical/fuel spills)
should be removed by a licensed waste management company.
12.6. Oil Sheens
With a steady influx of water Wth high concentrations of oil, a sheen maybe noticeable at the Stormceptor outlet. This may occur because a
rainbow or sheen can be seen at very small oil concentrations (,10 mg/L). Shhrmcephhr vdll remove over 98% of all free oil spills from shhrm
sewer systems for dry weather or frequently occurring runoff event.
The appearance of a sheen at the outlet Wth high influent oil concentrations does not mean the unit is not working m this level of removal.
I addition, if the influent oil is emulsified the Shhrmceptor will not be able to remove it The Shhrmcephhr is designed for free oil removal
and not emulsified conditions.
SUPPORT
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NOTHING IN THE CATALOG 5HOULD BE CONSTRUED ASA WARRANTY AWLICATIONS SUGGESTED HEREIN ARE DESCRIBED ONLY TO HEV READERS MAKE
THEIR OWN EVALUATIONS AND DECISIONS, AND ARE NEITHER GUARANTEE MR WARRANTIES OF SURABILIIY EOR ANY AFMCATION. CONTLCH MAKES
NOWARPANTYWHADOEVER, EXPRESSORIBRUED, REIATEDTO THE APEICATIONS,MATERIALS, COADNGS, OR PRODUCE DISCUSSED HEREIN. ALL
CULAR PURPOSE ARE ELAIMED In CONTECN.
WARRANTIES OF MERCHANTABILITY AND ALL IMPLIED WARRANTIES OF FITNESS MR ANY PAW SC
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Appendix 4
Notice of Operations and Maintenance Plan
PARADIGM MARCOLI APARTMENTS I KPFF CPmulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Notice of Operations and Maintenance Agreement
Private Stormwater Management and Treatment System
The undersigned owner(s), is hereby given notice that stormwater runoff from the "Property' described below
requires stormwater management facilities to be located, designed, and constructed in compliance with the City
of Springfield's Engineering Design and Procedures Manual. Said facilities shall be operated and maintained
in accordance with the Operations and Maintenance Agreement (O&M Agreement) on file with the City of
Springfield, Development and Public Works Department.
Paradigm Marcola LLC (Property Owner/Developer)
acknowledges and agrees to maintain private stonnwater treatment facilities listed in this document. The
maintenance of the stomnwater facilities listed in this document is required as part of the Development
Agreement with the City of Springfield. This facility will be operated and maintained in accordance with the
requirements stated in this document and in the latest edition of the City of Springfield Engineering Design
Standards and Procedures Manual, Chapter 3. The City reserves the right to enter and inspect any stow nwater
facility located on the "Property' to ensure the facilities are operating as designed. Failure of the responsible
party to inspect and maintain the facilities can result in an adverse impact to the public stomnwater system and
the quality of receiving waters.
The requirement to operate and maintain the stonnwater treatment facilities in accordance with the approved
site development agreement and the site O&M Agreement is binding on all current and future owners of the
property. The Agreement and its O&M Plan may be modified under written consent of new owners with
written approval by and re -filing with the City. The O&M Agreement and O&M Plan for facilities constructed
pursuant to this notice are available at the Development and Public Works Department, 225 Fifth St, Springfield
Oregon, or call (541)-736-3753, between the hours of S a.m. and 5 IT m., Monday through Friday.
The Subject premises, is legally described as follows: (Tax lot minter cannot be usedto describe the property. Legal
rkscriphons may be obtatredfronn the coolly assessor's office).
SEE EXHIBIT "A"
ATTACHED HERETO AND INCORPORATED HEREIN BY REFERENCE
By signing below, the signer accepts and agrees to the terms and conditions contained in the Operations and
Maintenance Plan and in any documents attached. This instrument is intended to be binding upon the parties
hereto, their heirs, successors, and assigns.
In Witness whereof, the undersigned has executed this instrument on this day of
20
Owner(s):
Signature
Print Name
STATE OF OREGON, County of Lane,
❑ Thus instrnment as acknowledged beforeme on
by , owner(s) of the above
described premises.
❑ Thus instrnment as acknowledged beforeme on
by
as
of
Notary Public for Oregon
RETURN TO: CITYOF SPRINGFIELD
DEVELOPMENT &PUBLIC WORKS DEPT.
225 FIFTH ST.
SPRINGFIELD, OREGON 97477
owner(s) of the above described
My Commission Expires
RESERVE THIS SPACE
FOR RECORDING STICKER
"Avoid $20 nonstanda orc (font too small)...
Print this form on Legal size paper."
Appendix 3A-1 RevontTltD Page 1 of 1 EDSP Adopted December 03, 2012
Appendix 5
Form 0&M: Operations and Maintenance Plan
PARADIGM MARCOLI APARTMENTS I KPFF CPmulting Engineers
OPERATIONS AND MAINTENANCE PIAN
Operations and Maintenance Agreement
Private Stormwater Management and Treatment System
Land Development Application Number:
Owner's Name: Paradigm Marcola LLC
Phone No.: 541-484-7311
Mailing Address: 1381 Pearl Street
City Eugene State OR Zip 97401
Site Address:
City State Zip
Site Map and Tax lot No.: Map: 17032513 Lot: 800
(Or ottmh dxwneM with odtfitiond lot irfornvrtion ifthe fmility crosses mm thmr ore lot)
Type of Facility(ies) Stormwater Planter, vegetated swale, and water quality manhole.
Requirements
1) Stormwater Management Site Plan, (min. 8 1/2" x 11" attached to this form) showing the location of
the facility(ies) in relation to building structures or other permanent monuments on the site, sources of
runoff entering the facility(ies), and where stormwater will be discharged to after leaving the
facility(ies). Landscape and vegetation should be clear on the Plan submitted or submit a separate
Landscape Plan document showing vegetation type, location, and quantity (landscape plan). These
can be the same Plans submitted for development review.
The storrawater management facility(ies) shown on the Site Plan are arequired condition of
development approval for the identified property. The owner of the identified property is required to
operate and maintain the facility(ies) in accordance with the Facility Specific Operation and
Maintenance Plants) (O&M Plan(s)) attached to this form and on file with the City. The O&M Plan
for the fa.cility(ies) will be available at the Development and Public Works Department, 225 56 Street,
Springfield, Oregon between the hours of 8 a.m. and 5 p.m., Monday through Friday.
2) Financiallyresponsible party (circle one):
Property Owner Homeowner Association Other (describe)
3) Party(ies) responsible for maintenance (only if other than owner).
Daytime phone no.(_)_
Emergency/after-hours contact phone no ( )
Maintenance Contact Party(ies) Name & Business Address:
4) Maintenance practices and schedule for the stormwater facility(ies) are included in the Facility
Specific O&M Plan(s) attached to this form and filed with the Development and Public Works
Department, City of Springfield. The operation and maintenance practices are based on the version of
the City of Eugene's Stormwater Management Manual in effect at the date of development
application, as modified by any plans attached to this document at the time of signing.
Application Date:
By signing below, Filer accepts and agrees to the terms and conditions contained in the Operations and
Maintenance Plan(s) and in any document executed by Filer and recorded with it.
Filer Signature:
Print Name:
Appendix 3A-2 aerom&16 Page 1 of 1 EDSP Adopted December 03, 2012
Appendix 6
Facility Inspection and Maintenance Log
PARADIGM MARCOLI APAUMENT I KPFF CPmulting Engineers
OPERAMONS AND MAIMENANCE PIAN
STORMWATER MANAGEMENT FACILITY
INSPECTION AND MAINTENANCE LOG
Property Address:
Inspection Date:
Ins ection Time:
Inspected By:
Approximate Date/Time of Last Rainfall:
Type of Stormwater Management Facility:
Location of Facility on Site (In relation to buildings or other permanent structures):
Water levels and observations (Oil sheen, smell, turbidity, etc.):
Sediment accumulation and record of sediment removal:
Condition of vegetation (Height, survival rates, invasive species present, etc.) and record of
replacement and management (mowing, weeding, etc.):
Condition of physical properties such as inlets, outlets, piping, fences, irrigation facilities, and
side slopes. Record damaged items and replacement activities:
Presence of insects or vectors. Record control activities:
Identify safety hazards present. Record resolution activities:
Appendix 3A-3 Page 1 of 1 EDSP Adopted December 03, 2012
800 Willamette Street, Suite 400, Eupm, OR 97401 1
541-684-49021 www.kpif.mm 1