aka-fnsb-tanana1_SWPPP.pdf

Stormwater Pollution Prevention Plan (SWPPP)

For Construction Activities at:

Project Name: Tanana River Recreation Access Improvements

AK FNSB TANANA (1)

Project Site Location: 4400 S. Cushman St. Extension

City, County, State, Zip Code: Fairbanks North Star Borough, Alaska 99701

SWPPP Prepared for:

Organization Name: FHWA, Western Federal Lands Highway Division

Address: 610 East Fifth Street Vancouver, WA 98661-3801

Telephone Number: 360-619-7700

SWPPP Prepared by:

Name, Title: Schuyler Roskam, Environmental Scientist

Company/Organization: PND Engineers, Inc.

Address:

1506 W. 36th Ave.

Anchorage, Alaska 99503

Telephone Number: 907-561-1011

SWPPP Preparation Date: July 25, 2022 Estimated Construction Start Date: April 2023 Estimated Construction Completion Date: October 2024 Estimated Revegetation Start Date: August 2024 Estimated Revegetation Completion Date: October 2024

SWPPP TABs (SWPPP Inclusions)

TAB 1: SWPPP Narrative

TAB 2: NPDES Permit (Construction General Permit or Corresponding State Permit)

TAB 3: NOI, EPA/State Acknowledgement, Other Applicable EPA/State Correspondence

TAB 4: Delegation of Authority

TAB 5: Vicinity Maps

TAB 6: Erosion/Sediment Control Plan Sheets (plan set and BMP typical details)

TAB 7: Revegetation Plan (if applicable)

TAB 8: SWPPP Amendment Log

TAB 9: Inspection Reports

TAB 10: Corrective Action Log

TAB 11: Water Quality Monitoring, Reporting Requirements, and Reports (if applicable)

TAB 12: Training/Certification Logs

TAB 13: Government-Selected Waste, Borrow, Staging Sites

TAB 14: Grading and Stabilization Log

TAB 15: Hazardous Spill Plan or SPCC

TAB 16: Threatened and Endangered Species (Section 7) and

Historic Preservation (Section 106) Documentation

TAB 17: NPDES Quality Assurance Checklist

TAB 18: NPDES Notice of Termination (NOT)

TAB 1:

SWPPP NARRATIVE

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Table of Contents

SECTION 1: RESPONSIBLE PARTIES/CONTACT INFORMATION

1.1 Operator(s):

1.2 Construction Site SWPPP Contact(s):

1.3 SWPPP Prepared by:

1.4 NPDES Stormwater Permit

1.5 SWPPP Administrator

1.6 Permitting Authority for FHWA/WFLHD Projects

SECTION 2: PROJECT INFORMATION

2.1 Project Name and Location

2.2 Project Site Characteristics

SECTION 3: NATURE OF CONSTRUCTION ACTIVITY

3.1 General Description of Project and Scope of Work:

3.2 Sequence and Estimated Dates of Construction Activities

3.3 Potential Sources of Pollutants

SECTION 4: SITE MAPS

SECTION 5: DISCHARGES

5.1 Allowable Non-Stormwater Discharges

5.2 Receiving Waters:

5.3 Water Quality Monitoring Requirements

SECTION 6: COMPLIANCE WITH OTHER APPLICABLE REQUIREMENTS

6.1 Endangered Species Protection

6.2 Historic Preservation

6.3 Safe Drinking Water Act Underground Injection Control Requirements

SECTION 7: EROSION AND SEDIMENT CONTROLS

7.1 DELETED

7.2 Perimeter Controls

7.3 Sediment Track-Out

7.4 Stockpiled Soil or Other Erodible Materials

7.5 Minimize Dust

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7.6 Minimize Disturbance of Steep Slopes

7.7 Topsoil Conservation

7.8 Minimize Soil Compaction

7.9 Storm Drain Inlets and Culvert Inlets

7.10 Constructed Stormwater Conveyance Channels and Culvert Outlets

7.11 Sediment Basins

7.12 Chemical Treatment

7.13 Dewatering Practices

7.14 Erosion Control and Stabilization

7.15 Removal of BMPs

7.16 Post Construction Measures

SECTION 8: OPERATIONAL CONTROLS/GOOD HOUSEKEEPING MEASURES

8.1 Hazardous Spill Plan

8.2 Spills/Releases in Excess of Reportable Quantities

8.3 Equipment/Vehicle Fueling and Maintenance Practices

8.4 Equipment/Vehicle Washing

8.5 Material Handling and Waste Management

8.6 Designate Concrete Washout Areas

SECTION 9: INSPECTIONS

9.1 Inspection Frequency

9.2 Corrective Actions

SECTION 10: DELEGATIONS OF AUTHORITY

SECTION 11: STAFF TRAINING

SECTION 12: CERTIFICATION AND NOTIFICATION

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Section 1: Responsible Parties/Contact Information

1.1 Operator(s):

Organization Name: FHWA, Western Federal Lands Highway Division (WFLHD) Address: 610 East Fifth Street

Vancouver, WA 98661-3801 Telephone Number: 360-619-7700

General Contractor Name:

TBD

Telephone Number:

Contractor and PE Note: Fill in all incomplete information following contract award date and prior to start of construction

1.2 Construction Site SWPPP Contact(s):

FHWA Contact Name:

Title:

Brandon Stokes Project Manager

Address: 610 East Fifth Street, Vancouver WA 98661 Telephone Number: 306-210-3636

General Contractor Company:

TBD

Erosion Control Supervisor Name:

Telephone Number:

1.3 SWPPP Prepared by:

Organization/Company: PND Engineers, Inc.

Name, Position: Schuyler Roskam, Environmental Scientist Role/Responsibility SWPPP Preparer AK-CESCL # AGC-21-0430 Telephone Number: 907-561-1011 Email: sroskam@pndengineers.com

1.4 NPDES Stormwater Permit

The Applicable EPA/State NPDES Stormwater Permit is located in TAB 2. The Project NOI and EPA/State Acknowledgement with NPDES Tracking Number is located in TAB 3.

1.5 SWPPP Administrator

The General Contractor (section 1.2) is responsible for maintaining the project SWPPP of Record. The General Contractor will provide a qualified Erosion Control Supervisor, who is

[2] responsible for managing the installation, maintenance, inspection, and reporting for erosion and sediment control measures, shall maintain and update the project SWPPP of Record and prepare all documentation required by the project NPDES stormwater permit and SWPPP.

The Erosion Control Supervisor (ECS) is identified in section 1.2 and his/her qualifications are documented in TAB 12.

The FHWA/WFLHD Project Engineer (PE) is the duly authorized representative of the FHWA for the purpose of overseeing compliance with the NPDES stormwater permit and SWPPP at the construction site. See Delegation of Authority TAB 4.

All SWPPP documentation, revisions/updates, and reports will be approved/signed by both the General Contractor’s ECS and the FHWA PE.

1.6 Permitting Authority for FHWA/WFLHD Projects

Delivery Confirmation documentation of the NOI is located in TAB 3.

The applicable EPA/State NPDES permit is located in TAB 2 Alaska Department of Environmental Conservation (ADEC)

State Permitting Authority Alaska

• ADEC is permitting authority for most discharges within the state EXCEPT for:

• EPA is the permitting authority for the Denali National Park and Preserve and Metlakatla

Indian Reservation.

The NOI for Alaska projects (through the ADEC) can be filed electronically at Alaska Pollutant Discharge Elimination System Program website. The completed SWPPP will be submitted to either ADEC or the Municipality based on the project type and operator described in the ADEC CGP.

http://dec.alaska.gov/water/wnpspc/stormwater/index.htm http://dec.alaska.gov/water/wnpspc/stormwater/APDESeNOI.html

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Section 2: Project Information

2.1 Project Name and Location

This basic site information is used to file for National Pollutant Discharge Elimination System (NPDES) permit coverage. Permit coverage is obtained by filing the Notice of Intent (NOI) after the SWPPP is complete.

Project Name: Tanana River Recreation Access Improvements

Project Site Location: 4400 S. Cushman St. Extension

City, County, State, Zip Code: Fairbanks North Star Borough, Alaska 99701

Latitude/Longitude:

64.797809, -147.710811

The method used for determining latitude/longitude was: Other Website Google Earth Pro

Township: Range: Section:

1S 1W 27

Is the project located in an American Indian or Alaskan Native area?

(previously referred to as Indian Country) No

If yes, the name of Reservation is: NA

Are you applying for permit coverage as a “federal operator?” Yes

The project Does Not discharge stormwater into a Municipal Separate Storm Sewer System.

2.2 Project Site Characteristics

The undeveloped site and features of the land that are incorporated into the final soil Erosion and Sediment Control plan sheets (TAB 6), as well as natural resources that should be protected are described below:

Vegetation, trees, and sensitive areas, such as stream buffers, wetlands, highly erodible soils, and steep slopes at the site include:

The project leads up to, but does not enter the Tanana River. The newly constructed road will traverse wetlands, as well as a slough that drains Cushman Lake to the Tanana River. The project area has standing water, drainage sloughs, manmade lakes, and several small ponds. The project area south of the Tanana Levee is within the Tanana River Federal Emergency Management Agency (FEMA) 100-year floodplain and is susceptible to inundation. Vegetation includes tundra, tussocks, scrub-shrubs, broad-leaved deciduous trees, and needle-leaved evergreen

[4] trees. The topography is generally level; however, there are groins for flood control which are 12 feet tall that will require significant grade adjustments for the proposed roadway to match. The levee and groin side slopes are generally sloped at a 2 horizontal; 1 vertical. Some existing sections are protected with riprap erosion protection. Cinch Street is a groin, acting as part of the levee system, and is approximately 12 feet above existing grade.

Wetlands surrounding the proposed roadway are potential receiving waters, as well as Cushman Lake. The wetlands present in the project area were delineated and were divided into 10 identified areas.

Also, see TAB 6

Stormwater currently drains from the site in the following manner:

Stormwater drains from the site via soil infiltration and sheet flow into adjacent road embankment and ditches.

Also, see TAB 6

The location of discharge points or areas:

Culvert outlets, roadside ditches that drain into surface waters and their adjacent vegetated buffers. Receiving waters include: Cushman Lake, Tanana Lake, Tanana River, and adjacent wetlands.

Also see TAB 6

The location of all waters, including wetlands, are shown on the site map located in TABs 5 and 6.

Critical slopes and slope lengths include:

None.

Soil type(s) of highly erodible soils and the soil infiltration capacity are identified as:1

Soils generally consist of floodplain riverwash with peat and mucky silt loams according to the USDA Soils Database for the project area.

Any past soil contamination at the site is identified as:

Alaska DEC Contaminated Sites GIS database shows one previously contaminated site over one-quarter mile from the project area. ADEC has classified this site as cleanup completed, with no other contaminated sites are within proximity to the

1 NRCS Web Soil Survey.

http://websoilsurvey.nrcs.usda.gov/app/WebSoilSurvey.aspx

[5] project area. No Superfund sites were found within proximity to the project area, as searched in the EPA Superfund Site database.

Protected Natural Features (natural features include trees, streams, wetlands, slopes, etc.):

See first block under this section. Also see TAB 6.

Measures to protect these features:

Project will utilize erosion and sediment control BMPs to avoid discharging sediment-laden, construction stormwater runoff into the neighboring wetlands.

Project disturbance limits will be clearly marked using fencing, flagging tape, or staking per the requirements of Site Delineation (AK BMP-54).

Rainfall:

10-year Mean Annual Precipitation at the Project Site (inches):2 11.37

Frequency, intensity, and duration of rainfall for the project site:

(principal factors influencing erosion from a construction site)

The 2-year, 24-hour storm event:3

1.09 inches/day

The 10-year, 24-hour storm event:

1.83 inches/day

The 25-year, 24-hour storm event:

2.33 inches/day

Approximate Growing Season at the Project Site: May 03 – October 03 (Regional Supplement to the Corps of Engineers Wetland Delineation Manual: Alaska Region (Version 2.0), US Army Corps of Engineers).

Approximate Freeze-Up and Spring Thaw Dates at Project Site: August 10 (fall freeze) – May 02 (spring thaw) (Fairbanks, Alaska “Fall ‘Freeze’ and Spring ‘Freeze’ Probabilities.” Western Regional Climate Center. Web. 17 May. 2021.)

2 NOAA City Climate Data 3 NOAA Precipitation Frequency https://www.ncdc.noaa.gov/cag/ https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_map_ak.html

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Section 3: Nature of Construction Activity

3.1 General Description of Project and Scope of Work:

(i.e., highway construction, roadway realignment, highway and bridge reconstruction, etc.):

The Western Federal Lands Highway Division (WFLHD) of the Federal Highway Administration (FHWA), in cooperation with the Fairbanks North Star Borough (FNSB), and the Department of the Army, Fort Wainwright, proposes construction of new access, parking, and facility improvements to the existing Tanana River Recreation Area. The overall project scope will replace an existing railroad crossing and enhance roadway access for ease of public use of the recreational area. Additional improvements under this project include parking lot resurfacing and expansion at the swim beach, new restroom installations, ADA-compliant pathway connecting existing trails, parking lot upgrades, and a widened area to accommodate a future entrance station.

The type or function of the project is: Road Construction, Parking, Facility, and Multiuse Trails

Construction Support Activities: If applicable, describe any construction support activities, such as dedicated concrete or asphalt batch plants, dedicated aggregate sites, equipment staging yards, material storage areas, borrow, or disposal sites (government-selected sites):

To be completed by contractor

Support Activity Location

Dedicated

Yes No

Concrete Batch Plant N/A ☐ Asphalt Batch Plant N/A ☐

Equipment Staging Yards

See maps. Potential staging areas include:

• Expanded area located west of

Swim Beach parking.

• Either side of Motorized Boat

Launch driveway.

Material Storage Areas See maps. Potential staging areas include:

• Either side of Motorized Boat Launch driveway.

Excavated Material Disposal Areas

Unsuitable material excavated during construction will be immediately hauled off-site to reduce risk of sediment transport.

Borrow Areas No borrow areas are anticipated for this project. ☐

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NOTE: All Contractor-selected sources and support sites are the sole responsibility of the General Contractor. The SWPPP and NPDES permitting for Contractor-selected sites and sources are separate from this documentation (SCR 107.01A(h)).

Support activities are located on the general vicinity map and/or site map in TAB 5 and TAB 6.

Size of Project Action Area:

(Including all Government-selected support sites such as staging, borrow, waste, access roads, affected downstream area, noise perimeter, extent of light effects, etc.)

Estimated Area Units

Total project area (within outermost project boundary): 28 acres

Disturbed project area (area of digging within total project area): 18 acres

Percent Impervious Project Area BEFORE Construction: 55 % Runoff Coefficient BEFORE Construction: 0.61

Percent Impervious Project Area AFTER Construction: 84 % Runoff Coefficient AFTER Construction: 0.92

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3.2 Sequence and Estimated Dates of Construction Activities

The intended construction sequencing and timing of major construction activities is detailed here, including the phased grading and stabilization activities used to minimize overall amount of disturbed soil.

Contractor and PE Note: Fill in all incomplete information following contract award date and prior to start of construction

Phase:

Construction sequence description: Duration of sequence:

BMPs associated with this sequence: Stabilization measures:

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Phase:

Construction sequence description: Duration of sequence:

BMPs associated with this

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Construction sequence description: Duration of sequence: BMPs associated with this

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Construction sequence description: Duration of sequence: BMPs associated with this

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Construction sequence description: Duration of sequence:

BMPs associated with this

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3.3 Potential Sources of Pollutants

The follow table identifies all potential sources (checked activities in column 1) of sediment and other sources of pollution, which may reasonably be expected to affect the quality of stormwater discharges from the construction site.

Se le ct ed

A ct iv ity

(X

Construction Activity

Potential Construction Site Pollutants

Se di m en t

N ut ri en ts

B ac te ri a pH

O il

G re as e

T ra sh

D eb ri s

Pe st ic id es

H ea vy M et al s

O th er

Po llu ta nt s

Clearing, excavating, and grading X X

Fill of roadway embankment, backfill at structures X X

Vehicle/equipment fueling and maintenance X X X

Vehicle/equipment use and storage X X

Sanitary/septic waste X X

Dewatering operations X X

Drilling and blasting operations X X X

Concrete washout and waste X X

Structure construction/painting/cleaning X X X X

Demolition and debris disposal X X X X X

Solid waste (trash and debris) X X

Hazardous waste or contaminated spills X X X

Paving operations X X

Landscaping operations X X X

Mining, rock extraction, crushing X X X

Contractor and PE Note: Fill in all incomplete information following contract award date and prior to start of construction

Construction and waste material expected to be stored on-site includes:

Material Storage Location

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Section 4: Site Maps

Vicinity maps are located in TAB 5.

Site maps and erosion and sediment control plan maps are located in TAB 6.

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Section 5: Discharges

Industrial stormwater discharges associated with industrial activity other than construction at the site (including dedicated asphalt plants and dedicated concrete plants that are covered by this permit) include:

NOTE: An Industrial Activity Multi-Sector General Permit may be required for some activities.

Industrial Activity Stormwater Discharge Location Multi-Sector General Permit Number (if applicable)

1. N/A

5.1 Allowable Non-Stormwater Discharges

Non-stormwater discharges used at the construction sited are identified below, along with control measures used to eliminate or reduce the discharges and BMPs used to prevent stormwater contamination.

Applicable to this Project

(check all that apply)

Potential Non-Stormwater Discharges Control Measures

To be completed by contractor

Waters used to wash vehicles where detergents are not used Water used to control dust Do not overwater.

Potable water including uncontaminated water line flushings Construction dewatering (uncontaminated) Monitor to ensure sediment laden water does not reach a water body.

Ground water or spring water (uncontaminated) Monitor to ensure sediment laden water does not reach a water body.

Routine external building wash down that does not use detergents Pavement wash waters where spills or leaks of toxic or hazardous materials have not occurred (unless all spilled material has been removed) and where detergents are not used

Foundation or footing drains where flows are not contaminated with process materials such as solvents

Landscape irrigation Monitor to ensure sediment laden water does not reach a water body.

Discharges from emergency fire-fighting activities N/A Fire hydrant flushings Uncontaminated air conditioning or compressor condensate

NOTE: The likely locations of these discharges are identified on the site map TAB 5 and/or

TAB 6

5.2 Receiving Waters:

Are there any surface waters located within 50 feet of the construction disturbance? Yes-

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Name(s) of the first surface water that receives stormwater directly from your site and/or from the MS4

1. Cushman Lake

2. Tanana Lake

3. Tanana River

4. Wetlands

Impaired Waters/TDMLs:

Answer the following for each surface water listed in Table 1:

Is this surface water listed as “impaired?”

What pollutant(s) is causing the impairment?

Has a TMDL been completed?

Pollutant(s) for which there is a TMDL

1. Yes No Yes No

2. Yes No Yes No

3. Yes No Yes No

4. Yes No Yes No

Source used to determine whether or not your project discharges into an impaired water:

Alaska DEC Water Quality Map

Tier 2, 2.5 or 3 Waters Answer the following for each surface water listed in Table 1:

Is this surface water designated as Tier 1,2 or 3?

If yes, specify which Tier.

1. Yes No Choose an item.

2. Yes No Choose an item.

3. Yes No Choose an item.

4. Yes No Choose an item.

If applicable, documentation of consultation with State or Federal TMDL authorities on consistency of SWPPP conditions with the approved TMDL is found in TAB 11. The control measures required to ensure that discharge of pollutants from the site are consistent with the assumptions and requirements of the EPA-established or approved TMDL, including any specific waste-load allocations are included in that documentation.

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5.3 Water Quality Monitoring Requirements

Provisions in Permit Conditions of the applicable NPDES stormwater permit, as well as the associated §401 certification or other special conditions, define additional monitoring and reporting requirements. Details about water quality monitoring and reporting requirements applicable to this project are included in TAB 11.

Samples and measurements taken for the purpose of monitoring will be representative of the monitored activity. Records of all monitoring information will be retained in TAB 11, including all calibration and maintenance records and all original strip chart recordings for continuous monitoring instrumentation.

Records of monitoring information will include:

1. The date, exact place, and time of sampling or measurements;

2. The individual(s) who performed the sampling or measurements;

3. The date(s) analyses were performed

4. The individual(s) who performed the analyses;

5. The analytical techniques or methods used; and

6. The results of such analyses.

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Section 6: Compliance with Other Applicable Requirements

6.1 Endangered Species Protection

Under which criterion is project eligible for Endangered Species coverage under the NPDES permit (EPA)?

A B C D E F

Criterion A. No federally-listed threatened or endangered species or their designated critical habitat(s) are likely to occur in your site’s “action area” as defined in Appendix A of EPA permit.

Criterion B. The construction site’s discharges and discharge-related activities were already addressed in another operator’s valid certification of eligibility for your action area under eligibility Criterion A, C, D, E, or F and there is no reason to believe that federally-listed species or federally-designated critical habitat not considered in the prior certification may be present or located in the “action area”. To certify your eligibility under this Criterion, there must be no lapse of NPDES permit coverage in the other operator’s certification. By certifying eligibility under this Criterion, you agree to comply with any effluent limitations or conditions upon which the other operator's certification was based. You must include in your NOI the tracking number from the other operator’s notification of authorization under this permit. If your certification is based on another operator’s certification under Criterion C, you must provide EPA with the relevant supporting information required of existing dischargers in Criterion C in the EPA NOI form.

Criterion C Federally-listed threatened or endangered species or their designated critical habitat(s) are likely to occur in or near your site’s “action area,” and your site’s discharges and discharge-related activities are not likely to adversely affect listed threatened or endangered species or critical habitat. This determination may include consideration of any stormwater controls and/or management practices you will adopt to ensure that your discharges and discharge-related activities are not likely to adversely affect listed species and critical habitat. To make this certification, you must include the following in your NOI: 1) any federally listed species and/or designated habitat located in your “action area”; and

2) the distance between your site and the listed species or designated critical habitat (in miles). You must also include a copy of your site map with the NOI.

Criterion D. Coordination between you and the Services has been concluded. The coordination must have addressed the effects of your site’s discharges and discharge-related activities on federally-listed threatened or endangered species and federally-designated critical habitat, and must have resulted in a written concurrence from the relevant Service(s) that your site’s discharges and discharge-related activities are not likely to adversely affect listed species or critical habitat. You must include copies of the

[16] correspondence between yourself and the Services in your SWPPP and

NOI.

Criterion E. Consultation between a Federal Agency and the U.S. Fish and Wildlife Service and/or the National Marine Fisheries Service under section 7 of the ESA has been concluded. The consultation must have addressed the effects of the construction site’s discharges and discharge-related activities on federally-listed threatened or endangered species and federally-designated critical habitat. The result of this consultation must be either:

i. a biological opinion that concludes that the action in question (taking into account the effects of your site’s discharges and discharge-related activities) is not likely to jeopardize the continued existence of listed species, nor the destruction or adverse modification of critical habitat;

or

ii. written concurrence from the applicable Service(s) with a finding that the site’s discharges and discharge-related activities are not likely to adversely affect federally-listed species or federally-designated habitat.

You must include copies of the correspondence between yourself and the Services in your SWPPP and NOI.

Criterion F. Your construction activities are authorized through the issuance of a permit under section 10 of the ESA, and this authorization addresses the effects of the site’s discharges and discharge-related activities on federally-listed species and federally-designated critical habitat. You must include copies of the correspondence between yourself and the Services in your SWPPP and NOI.

Support Documentation for Endangered Species criterion eligibility is filed in TAB 16.

6.2 Historic Preservation

1. Will the project involve installation of any of the following stormwater controls that entail subsurface earth disturbance? Yes

Dike Berm Catch Basin Pond Ditch, trench, swale, perimeter drain, etc.

Culvert Other ground-disturbing stormwater control Click here to enter text.

If the project involves no installation of earth-disturbing stormwater controls, then no further historic preservation screening is necessary (for NPDES permitting purposes).

2. If answer to step 1 is Yes, have professional surveys or evaluations determined that historic properties do not exist (or have prior disturbances at the site precluded the existence of historic properties)? No

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Provide documentation for the basis of this determination. Click here to enter text.

3. If answer to step 2 is No, have professional surveys or evaluations determined that installation of stormwater controls will have no effect on historic properties? Yes Provide documentation for the basis of this determination. Cultural Resources Field Survey Report (No Historic Properties Affected), December 18, 2020

4. Has the State Historic Preservation Officer (SHPO), Tribal Historic Preservation Office (THPO) or other tribal representative concurred with the determinations of effects on historic properties? Yes Provide the nature of their response. Alaska State Historic Preservation Office Letter of Concurrence (3130-1R WFLHD), February 23, 2021.

6.3 Safe Drinking Water Act Underground Injection Control Requirements

Will the project plan install any of the following controls? No Check all that apply:

Infiltration trenches (if stormwater is directed to any bored, drilled, driven shaft or dug hole that is deeper than is widest surface dimension, or has a subsurface fluid distribution system)

Commercially manufactured pre-cast or pre-built proprietary subsurface detention vaults, chambers, or other devices designed to capture and infiltrate stormwater flow.

Drywells, seepage pits, or improved sinkholes (if stormwater is directed to any bored, drilled, driven shaft or dug hole that is deeper than its widest surface dimension, or has a subsurface fluid distribution system)

If yes, provide documentation of communications with the EPA or applicable State agency.

Click here to enter text.

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Section 7: Erosion and Sediment Controls

Note: Contractor and PE – If any additional control methods are put in place, or there are any modifications to existing control methods, make notes in this section accordingly.

Control measures at the construction site are selected, installed, implemented, and maintained to minimize pollutants in the discharge as necessary to meet applicable water quality standards.

The objectives of this SWPPP include:

• Stabilize the site as soon as possible (targeting the preparation and implementation of erosion and sediment controls to get the site to final grade, and either permanently or temporarily stabilize all bare soil areas as soon as possible).

• Perimeter controls will be installed before ground disturbing activities are initiated.

• Perimeter protection will remain in place until final stabilization has been achieved.

• Slopes and channels will be protected by conveying concentrated stormwater runoff around the top of slopes and stabilize slopes as soon as possible. Avoid disturbing natural channels and the vegetation along natural channels as much as possible.

• Divert stormwater coming on to the site by conveying it safely around, through, or under the work area. (Divert the clean water, trap the dirty water.)

• Protect receiving waters and other environmentally sensitive waters or areas adjacent to the site.

• Follow pollution prevention measures by providing proper containers for waste and garbage at the site. Store hazardous materials and chemicals so that they are not exposed to stormwater.

• Minimize the area and duration of exposed soils. Clear only land that will be under construction in the near future.

7.1 Natural Buffers or Equivalent Sediment Controls (Required for EPA CGP states only – ID, WA)

Note: Section Not Applicable.

This section only applies if a surface water is located within 50 feet of the project’s earth disturbing activities.

Are there any surface waters within 50 feet of the project’s earth disturbances? Yes

If No, then no further documentation is required for the SWPPP.

NOTE: Reference EPA CGP appendix G for buffer guidance.

If Yes, check which natural buffer compliance alternative is used at the project site:

The project will provide and maintain a 50-foot wide undisturbed natural buffer.

The location and width of natural buffers are shown on the Erosion and Sediment Control

Plan sheets in TAB 6.

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The project will provide and maintain an undisturbed natural buffer that is less than 50 feet in width and is supplemented by additional erosion and sediment controls, which in combination achieves the sediment load reduction equivalent to a 50-foot undisturbed natural buffer.

The location of natural buffers are shown on the Erosion and Sediment Control Plan sheets in TAB 6.

Insert the width of the natural buffer to be retained Vegetative buffers will be delineated as described in 10.1 and shall have a minimum width of 25 feet unless found infeasible.

Insert description of additional erosion and sediment controls to be used in combination with the natural buffer: Compost socks, fiber rolls, and silt fence will be installed as appropriate. See TAB 6.

Document the method used to determine that the above combination of natural buffer and sediment and erosion controls equal the estimated sediment removal capacity of a 50-foot undisturbed natural buffer:

It is infeasible to provide and maintain an undisturbed natural buffer of any size, therefore, the project will implement erosion and sediment controls that achieve the sediment load reduction equivalent to a 50-foot undisturbed natural buffer.

Insert rationale for concluding that providing and maintaining a natural buffer of any size is infeasible: Click here to enter text.

Insert description of erosion and sediment controls to be used to achieve the sediment load reduction equivalent to a 50-foot undisturbed natural buffer: Click here to enter text.

The project qualifies for one of the exceptions in EPA CGP Part 2.1.2.1.e

For a “linear project”, site constraints (e.g. limited right of way) make it infeasible for the project to meet any of the CGP part 2.1.2.1.a compliance alternatives.

Other exception (state type): Click here to enter text.

Document why it is infeasible to meet one of the buffer compliance alternatives: Click here to enter text.

Insert description of erosion and sediment controls to be used to achieve the sediment load reduction equivalent to a 50-foot undisturbed natural buffer: Click here to enter text.

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7.2 Perimeter Controls

All Perimeter Sediment Controls will be installed prior to ground disturbing activities taking place. There will be no clearing or grubbing outside the physical clearance limits.

Locations and design specifications of BMPs are shown on the erosion and sediment control plan sheets in TAB 6.

The following perimeter controls will be implemented:

Measure: Fiber rolls Implementation: All fiber rolls will be installed prior to any ground disturbing activities. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Sediment will be removed from fiber roll perimeter controls before deposits reach 50% of the above ground height. It is the Contractor’s responsibility to upgrade erosion control measures as necessary if the sediment controls are ineffective and turbid water is observed discharging from the site. Fiber rolls will not be removed until vegetation is satisfactorily established.

Contractor and PE Note: Add additional measures used during construction.

7.3 Sediment Track-Out

The following methods will be implemented to minimize off-site vehicle tracking of sediment onto paved surfaces. If sediment escapes the construction site, off-site accumulations of sediment will be removed at a frequency sufficient to minimize off-site impacts.

Locations and design specifications of BMPs are shown on the erosion and sediment control plan sheets in TAB 6.

Measure: Stabilized Construction Exit Implementation: All construction exits will be installed prior to any ground disturbing activities.

Construction traffic will be limited to enter and exit the site via the stabilized construction exits.

Maintenance: Remove build up sediment to minimize tracking out onto roadways. If sediment escapes the construction site, off-site accumulations of sediment must be removed at a frequency sufficient to minimize off-site impacts. Remove the track-out by sweeping, shoveling, or vacuuming these surfaces, or by using other similarly effective means of sediment removal.

Note: Add additional measures used during construction.

[21]

7.4 Stockpiled Soil or Other Erodible Materials

Stockpile management includes measures to minimize surface erosion and sediment transport from soil stockpiles or other erodible materials.

Locate erodible stockpiles away from drainages including storm sewer inlets and culvert inlets.

Locations of stockpiles are shown on the erosion and sediment control plan sheets in TAB 6.

Measure: Distribute layer of soft vegetative topsoil after compaction complete Implementation: After soil compaction is complete and prior to revegetation efforts. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Maximize depth whenever possible and seed as soon as practicable. If seeding cannot occur in a timely manner, other BMPs (nets, blankets, etc.) will be placed to mitigate erosion.

Measure: Fiber rolls Implementation: All fiber rolls will be installed prior to any ground disturbing activities. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Sediment will be removed from fiber roll perimeter controls before deposits reach 50% of the above ground height. It is the Contractor’s responsibility to upgrade erosion control measures as necessary if the sediment controls are ineffective and turbid water is observed discharging from the site. Fiber rolls will not be removed until vegetation is satisfactorily established.

Measure: Plastic sheets Implementation: Soil stockpiles and other erodible materials should be covered by plastic as soon as they are generated. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Contractor should frequently check plastic to ensure soil or other erodible material is covered.

Contractor and PE Note: Add additional measures used during construction.

7.5 Minimize Dust

Dust control includes practices used to reduce or prevent the surface and air transport of dust during construction Measure: Dust Control Implementation: During active construction as needed. Apply at a rate of 3 gallons per acre, using a diffused or sprinkled flow. Care should be taken not to saturate or muddy the dust and that dust generation does not increase. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Application of water for dust control requires constant attention. Sprinkling will likely need to be done several times per day, especially during hot, dry weather.

[22]

7.6 Minimize Disturbance of Steep Slopes

Describe how disturbance of steep slopes will be minimized. Describe controls (e.g. erosion control blankets, tackifiers) that will be implemented to minimize sediment discharges from slope disturbances.

If applicable, describe how stormwater run-on and run-off will be managed. Flows may be diverted from exposed soils by retaining/detaining flows or otherwise minimizing runoff and the discharge of pollutants from exposed areas of the site. Placement of structural practices in floodplains will be avoided to the degree technologically and economically practicable and achievable.

Measure: Fiber rolls Implementation: All fiber rolls will be installed prior to any ground disturbing activities. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Sediment will be removed from fiber roll perimeter controls before deposits reach 50% of the above ground height. It is the Contractor’s responsibility to upgrade erosion control measures as necessary if the sediment controls are ineffective and turbid water is observed discharging from the site. Fiber rolls will not be removed until vegetation is satisfactorily established.

Measure: Slope roughening Implementation: Surface roughening should be performed on all steep slopes immediately after final grading or to temporarily stabilize an area during active construction. Roughening should create depressions 2-4” deep running parallel to the contours of the land.

Maintenance: Care should be taken not to drive equipment over areas that have been previously surface roughened. Surface roughening is only a temporary control, so additional treatments may be necessary to maintain the soil surface in a roughened condition for adequate erosion control.

7.7 Topsoil Conservation

Describe how topsoil will be preserved, if feasible. If conservation of topsoil is infeasible, explain why, and describe alternate methods to be used to insure optimum vegetation survival and growth.

Erosion and sediment control measures for topsoil stockpiles (and other erodible materials) are shown in section 4.4.

Note: Contractor and PE – complete this section as appropriate.

☐ Conservation of topsoil is Infeasible:

Measure: Click here to enter text.

Implementation: Click here to enter text.

Maintenance: Click here to enter text.

[23]

☒ Conservation of topsoil is Feasible:

Measure: Topsoil Conservation Implementation: Earth disturbing activities will be limited to the minimum project area needed for construction in an effort to preserve natural vegetation and topsoil. All topsoil that is excavated for reuse will be stockpiled in a designated area to enhance the final site stabilization with vegetative cover.

Maintenance: All stockpiles should be inspected frequently for runoff potential, especially after a significant rainfall event. Stockpiles should be used in conjunction with erosion control practices.

7.8 Minimize Soil Compaction

Minimize soil compaction in areas where final vegetative stabilization will occur and where infiltration practices will be installed.

☐ Not applicable to this project. Reason: Click here to enter text.

If applicable:

Measure: Distribute layer of soft vegetative topsoil after compaction complete.

Implementation: After soil compaction is complete and prior to revegetation efforts.

Maintenance: Maximize depth whenever possible and seed as soon as practicable. If seeding cannot occur in a timely manner, other BMPs (nets, blankets, etc.) will be placed to mitigate erosion.

Contractor and PE Note: Add additional measures used during construction.

7.9 Storm Drain Inlets and Culvert Inlets

Applicable for stormwater drain inlets which are connected to separate storm sewer systems (usually in urban locations) AND for culvert inlets that discharge stormwater from the project into surface waters.

Locations and design specifications of BMPs are shown on the erosion and sediment control plan sheets in TAB 6.

The following BMPs are applicable to:

☐ Storm Drain Inlets ☒ Culvert Inlets

Measure: Fiber rolls Implementation: All fiber rolls will be installed prior to any ground disturbing activities. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Sediment will be removed from fiber roll perimeter controls before deposits reach 50% of the above ground height. It is the Contractor’s responsibility to upgrade erosion control

[24] measures as necessary if the sediment controls are ineffective and turbid water is observed discharging from the site. Fiber rolls will not be removed until vegetation is satisfactorily established.

Contractor and PE Note: Add additional measures used during construction.

7.10 Constructed Stormwater Conveyance Channels and Culvert Outlets

Describe velocity dissipation and/or erosion control devices to be installed at stormwater conveyance channels (such as roadside ditches) and culvert outlets. Includes permanent and temporary devices (specify).

Velocity dissipation devices will be placed at discharge locations and along the length of any outfall channel to provide a non-erosive flow velocity from the structure to a water course so that the natural physical and biological characteristics and functions are maintained and protected (e.g., no significant changes in the hydrological regime of the receiving water).

Locations and design specifications of BMPs are shown on the erosion and sediment control plan sheets in TAB 6.

Measure: Fiber Roll Check Dams Implementation: Following ditch construction. Where temporary or permanent channels are not yet vegetated, channel lining is infeasible and, therefore, velocity checks are required. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Regular inspections should be made to ensure that the center of the dam is lower than the edges. Sediment will be removed from check dams before deposits reach 50% of the above ground height. Check dams will not be removed until vegetation is satisfactorily established.

7.11 Sediment Basins

If applicable, provide site design specifications and other details for design of sediment basins and ponds. This may also include sediment infiltration swales.

Locations and design specifications of BMPs are shown on the erosion and sediment control plan sheets in TAB 6.

At a minimum, sediment ponds must provide storage for either the calculated volume of runoff from the 2-year, 24-hour storm event or 3,600 cubic feet per acre drained. Sediment ponds must also use outlet structures that withdraw water from the surface, unless infeasible.

☒ Not applicable to this project.

[25]

7.12 Chemical Treatment

If chemical sediment control (such as polymers) will be used, provide design specifications and other details considered when choosing treatment type and locations.

☒ Not applicable to this project.

7.13 Dewatering Practices

Discharge of ground water or accumulated stormwater that is removed from excavations, trenches, foundations, etc. into surface waters is prohibited unless such waters are first effectively managed by appropriate sediment controls. Uncontaminated non-turbid dewatering water can be discharge without being routed to a control.

☐ Not applicable to this project

Measure: Vegetated Sediment Filtration Areas Implementation: Delineate undisturbed natural areas of vegetation identified in the plans with methods consistent with the site delineation specification prior to commencement of clearing and grubbing operations or other soil disturbing activities. Vegetated sediment filtration areas should be completely enclosed by silt fence or fiber rolls in flat, vegetated, upland areas where discharges can infiltrate the ground.

Maintenance: Ensure all other sediment control measures used in conjunction with the vegetated sediment filtration areas are in place and functioning properly. Do no allow construction materials, equipment, or parking on the vegetated sediment filtration areas or where the root-zone of the vegetation may be damaged. Replace or repair site delineation as necessary. Repair any damage by equipment or vehicles. Inspect for sediment deposition throughout the filtration areas.

Measure: Fiber rolls Implementation: All fiber rolls will be installed prior to any ground disturbing activities. Please also refer to project schedule, contract, and plan set (Erosion Control section).

Maintenance: Sediment will be removed from fiber roll perimeter controls before deposits reach 50% of the above ground height. It is the Contractor’s responsibility to upgrade erosion control measures as necessary if the sediment controls are ineffective and turbid water is observed discharging from the site. Fiber rolls will not be removed until vegetation is satisfactorily established.

Measure: Diversion Dike Implementation: Construct diversion dikes and fully stabilize them before any major land disturbance begins.

Maintenance: Inspect diversion dikes as specified in the SWPPP to ensure continued effectiveness. Maintain dikes at their original height. Repair any decrease in height due to settling or erosion immediately. To remain effective, earth dikes must be compacted at all times.

[26]

7.14 Erosion Control and Stabilization

Commence temporary soil stabilization measures as soon as practicable if no further disturbance of an area of the site or stockpile is expected within the next 14 days. Complete temporary soil stabilization measures to disturbed sites or stockpiles within 21 days of last disturbance. Provide temporary stabilization of all exposed soil prior to winter construction shut down.

Specify whether stabilization measure is temporary or permanent.

Measure: Temporary Seeding Implementation: Install immediately at areas of the site where construction grading activities have temporarily ceased and are designated for stabilization with seeding mix and mulch.

Maintenance: Ensure adequate coverage. Ensure area receives adequate water according to the prescribed seeding specifications. Inspect for areas disturbed by foot traffic and/or equipment after installation. Verify seeding is applied during the appropriate seeding window. Prepare and reapply seeding mix to areas of disturbed or poor growth to maintain complete coverage, if necessary.

Contractor and PE Note: Add additional measures used during construction.

Measure: Permanent Seeding Implementation: Install immediately at areas of the site where construction grading activities have permanently ceased and are designated for stabilization with seeding mix and mulch.

Maintenance: Ensure adequate coverage. Ensure area receives adequate water according to the prescribed seeding specifications. Inspect for areas disturbed by foot traffic and/or equipment after installation. Verify seeding is applied during the appropriate seeding window. Prepare and reapply seeding mix to areas of disturbed or poor growth to maintain complete coverage, if necessary. Ensure frequent inspection are made until sufficient vegetative establishment has been made.

Contractor and PE Note: Add additional measures used during construction.

Measure: Temporary Slope Stabilization Implementation: Areas of the site that are designated with seeding mix and mulch will be track walked and applied with a soil tackifier or covered with a rolled erosion control blanket when construction grading activities have temporarily ceased for winter shutdown and it is past the seeding window.

Maintenance: Ensure adequate coverage. Inspect for areas disturbed by foot traffic and/or

[27] equipment after installation. During spring thaw conduct weekly inspections to ensure the integrity of ESC practices, repair damaged perimeter controls, and stabilize slopes as needed.

7.15 Removal of BMPs

Remove erosion and sediment control BMPs that are no longer needed and leave in good working order those BMPs that will remain at the construction site after close-out.

BMPs are no longer needed when the site that the BMP is protecting has reached final stabilization as defined in the applicable NPDES Stormwater Permit.

Final stabilization means:

• All ground disturbing activities at the site have been completed, AND

• Vegetation has been established that provides a uniform perennial vegetative cover with a density of 70% of the natural vegetative cover prior to construction.

• In arid (0-10” annual precipitation) or semiarid (10-20” annual precipitation) areas, final stabilization is considered to be achieved when the area is seeded or planted and vegetation is expected to provide 70% cover within 3 years; AND, erosion controls are in place that provide soil protection for at least 3 years without active…