Stormwater Pollution Prevention Plans for Construction Sites in Kentucky

Barry Tonning

Tetra Tech

Construction site runoff

control is one of the 6

minimum control

measures for MS4s

What does the KPDES

MS4 Stormwater

permit require?

KY MS4 KPDES Permit Requirements

• Permittee shall implement and enforce an ordinance or other regulatory mechanism that addresses stormwater runoff from active construction sites that disturb one acre or more, and those less than one acre in size that are part of a larger common plan of development or sale, located within the MS4

• Mandates that the permittee require construction site operators to implement appropriate erosion and sediment control best management practices (BMPs) that are as protective as KY’s General Permit for Construction sites (KYR100000)

• Requires that the permittee include, by ordinance or other regulatory mechanism, a requirement that discharges from construction sites to high quality waters protect existing instream water uses and the level of water quality necessary to protect the existing uses.

Ordinance requirements

• Site operators must implement BMPs at least as protective as the KPDES CGP

• Operators must control litter, waste, concrete truck washouts, sanitary waste

• Must certify that NOI has been submitted• Must have authority to review site plans to affirm

compliance with regulations• Procedures for receiving/considering public input• Must have authority to inspect & enforce• Requirements that operators protect HQ waters

MS4 program requirements

• Develop, implement, and enforce a construction management program with:– Permitting process and plan review– Procedures for periodic inspections

(recommendation: after 2 wks, then monthly)– Implementation of an enforcement strategy– Inventory & inspection prioritization procedure– Training program for staff & operators– Reporting on program activities

Overview of KPDES General Permit Construction Site Requirements

• Prepare a Stormwater Pollution Plan (SWPPP) to reduce pollutant discharges “to the maximum extent practicable”

• Apply for KPDES permit coverage by filing a “Notice of Intent”

• Implement (and amend) the SWPPP as construction proceeds – all operators at the site require coverage

• File a “Notice of Termination” when construction is completed

KPDES permit types

• Most sites can apply for General Permit coverage by filing a Notice of Intent (NOI) or eNOI– http://www.dep.ky.gov/formsfpermitapp/

• These projects must apply for Individual Permits:– Projects that discharge to an Impaired Water listed in

the most recent Integrated Report, §305(b) as impaired for sediment and for which an approved TMDL has been developed,

– Discharging into Cold Water Aquatic Habitat, an Exceptional Water, an Outstanding National Resource Water or Outstanding State Resource Water

– Other projects identified by the KY Division of Water

ONRWs and OSRWs

• “Outstanding National Resource Waters” means those “waters of the Commonwealth” that have been listed in Table 1 of 401 KAR 10:030, Section 1(1).

• “Outstanding State Resource Waters” means those “waters of the Commonwealth” that meet the criterion of 401 KAR 10:031, Section 8

When is a permit & SWPPP needed?

• Stormwater discharges from sites that disturb 1 acre or more of land, including those within a “common plan of development,” – e.g. a half-acre lot in a 5 acre

subdivision• Site “operator” is commonly

defined as: – Person with control over plans

and specifications– Person with day-to-day control

of site activities– Usually the owner, developer, or

contractor

NEW! Where discrete construction projects within a larger common plan of development or sale are located 0.25 mile or more apart and the area between the projects is not

being disturbed, each individual project can be treated as a separate plan of

development or sale provided any interconnecting road, pipeline or utility

project that is part of the same “common plan” is not concurrently being disturbed.

“Operator” means any party associated with a construction project that:

1. Has operational control over either the construction plans and specifications, including the ability to make modifications to those plansand specifications; or

2. Has day-to-day operational control of those activities at a project which are necessary to ensure compliance with a SWPPP for the site or other permit conditions (e.g., they are authorized to direct workers at the site to carry out activities required by the SWPPP or comply with other permit conditions).

SWPPP Applicability, Preparation, Contents, and Process for Amending

• SWPPP applies to the site AND offsite borrow/disposal areas

• SWPPP is prepared BEFORE filing the NOI and beginning work

• SWPPP describes site, pollutants at site, plan for controlling pollutant discharges, construction procedure, & responsible parties

• SWPPP is amended by site personnel or project engineer as construction proceeds on an as-needed basis

What is a SWPPP?

A detailed plan that:

• Describes the site and each major phase of the planned activity

• Identifies potential sources of stormwater pollution & any non-stormwater discharge

• Describes practices to reduce pollutants and the volume of discharges

• Identifies procedures the operator will implement to comply with the permit

• Outlines the roles and responsibilities of contractors and subcontractors

• Documents changes and modifications to the construction plans and activities

SWPPP & Other Site Plans

Site Grading

Plan

Site Building

Plan

Site Drainage

Plan

Existing Site

Conditions

Stormwater Pollution

Prevention Plan

Final Site Land-

scaping Plan

Tools for preparing the SWPPP

• KY BMP Tech Specs Manual – primary reference for construction site BMPs and SWPPP compliance: www.water.ky.gov

• Topographic, hydrology, water quality, and other mapping tools available at http://kygeonet.ky.gov/

• Your construction plans• Your visual site survey

Basic SWPPP outline

• Site description & map• Description of receiving waters• Description of construction project• Identification of pollutants, sources,

and any non-stormwater discharges• Erosion & sediment controls• Controls for other pollutants• Procedures for inspections, BMP

maintenance, and recordkeeping• Certification & signatures

SWPPP site description requirements

• Assess & describe potential for generating and discharging sediment & other pollutants– Includes land clearing, grading, cut/fill work– Also includes concrete washouts, porta-potties, materials

stored/handled onsite (e.g., paint, fertilizer), fuels/oils

• Describe project type and construction activities– Residential, commercial, industrial, transportation,

utilities– Usually land clearing and grading and construction of

roads, utilities, and buildings

• List sequence of soil-disturbing activities– Usually clearing, grading, roads/utilities, buildings, final

landscaping or stabilization

SWPPP site description (cont.)• Estimate area to be disturbed,

including off-site borrow/fill areas– Note this only includes areas that are

cleared, graded, excavated, or filled

• Describe water quality classification of receiving waters– Uses: WAH, CAH, DWS, ONRW,

OSRW, PCR, SCR– Meets the water quality criteria for the

KDOW beneficial use designation, or not

Classification of receiving waters

• Where does the precipitation from your site drain to?– Follow the downslope drainageways– Is there a waterway bordering your site,

or on your site?– Use a USGS 7.5 minute topographical

map• Must identify the named water body

that receives site drainage– Can be more than one!

• Must note status of receiving water(s)– Water may be meeting designated uses,

threatened, or impaired

http://kygeonet.ky.gov/kyhydro/main.htm

http://wdr.water.usgs.gov/nwisgmap/

Status of receiving water(s)

• Determined by Kentucky Division of Water

• Based on beneficial use designation and numeric/narrative water quality criteria– Meets criteria = meets designated uses– Impaired waters do not meet uses

• If water is impaired for sediment, special construction controls will likely be needed

• Check status at www.water.ky.gov

http://www.water.ky.gov/sw/swmonitor/305b/default.htm

Impaired waters map

Buffer zone requirements• 25 ft undisturbed buffer between disturbed areas

and bankfull elevation of high quality waters / impaired waters

• 50 buffer required between sediment-impaired waters with no TMDL and disturbed areas

• Dredge/fill areas,stream crossings,or other deviationsrequire “adequately protective” alternate practices, explainedin SWPPP

Requirements for Critical Areas

• KYR10 KPDES permit includes “a requirement to conduct immediate stabilization practices in critical areas near receiving waters for all projects”

• “Critical Areas” for the purposes of this permit means areas within 25 feet of, and on a positive slope toward a water of the Commonwealth

• Erosion prevention measures (e.g., blankets, mats, mulch, treading) “shall be implemented within 24 hours or as soon as practical after completion of disturbance/grading or following cessation of activities.”

SWPPP site map must include:• Project property boundaries, including lots

– Should be included in overall construction plans

• ID of lots that will have construction activity– Typically those covered under this NOI & SWPPP

• Existing and future drainage patterns, including slopes after grading– Important focus for adapting sediment controls over time

• Planned buildings, roads, sidewalks, parking lots, other impervious structures– Included in overall construction plans

• Areas of soil disturbance & no disturbance, including borrow/fill areas– Include both onsite and off-site areas!

SWPPP site map (continued)• Locations and types of erosion controls

– Areas with seed, mulch, sod, downdrains, etc.

• Locations and types of sediment controls– Silt fence, traps, basins, ditch checks, etc.

• Planned stabilization measures– Final stabilization: vegetation, impervious

cover, ditch stabilization (rock, grass, etc.)• Other site management practices

– Concrete washout, waste receptacles, porta-potties, material storage/handling, fueling, etc.)

SWPPP site map (continued)

• Location(s) of surface waters, including wetlands and riparian zones– See USGS topo maps or Kentucky Geonet

• Location(s) of karst features, such as sinkholes, springs, etc.– Some are on newer USGS maps and KY Geonet;

may require visual site survey

• Locations of discharge points– Includes both concentrated flow & sheet flow– Include storm drains/ditches, if applicable

Non-stormwater discharges

• If combined with construction site discharges, must identify pollution prevention measures for discharges from:– Firefighting, hydrant flushing– Non-detergent vehicle washing– Dust control, waterline flushing– Non-detergent building and pavement

washdown (no pollutants in discharge)– Landscape irrigation, groundwater, clean

dewatering

Endangered Species, Historical Sites, and Other Protected Areas

• Endangered or threatened species are more likely in undisturbed exurban or rural areas– Kentucky State Nature Preserves Commission can

provide site-specific information

• Historical sites include structures and burial sites– Check with local historical society or state office

• Other protected areas: wellhead protection zones, stream buffers, underground utilities– Usually requires site survey and consultation with

local agencies, utility companies, etc.

KPDES permit requirements on SWPPP implementation sequence

• Describe intended sequence of major stormwater controls

• Describe implementation schedule in relation to construction process

• Describe proposed construction schedule

• Describe interim and permanent stabilization practices, including schedule

KPDES permit requires addressing these management practices:

• Drainage system controls– Diversion berms– Conveyance channels– Vegetated buffers– Slope drains– Energy dissipaters– Vegetated filter strips

• Ditch and channel protection– Inlet protection– Outlet protection– Check dams– Liners

• Sediment traps and basins– Sediment traps & basins– Baffles / skimmers– Electro coagulation– Filtration and polymers

• Perimeter controls– Silt fence, berms, swales

• Exposed soil stabilization practices– Vegetation – grasses, etc.– Geotextiles– Straw and mulch– Erosion control blankets– Turf reinforcement mats

• Sediment control measures– Sediment barriers– Silt fences– Fiber rolls– Other practices

• Slope protection measures besides vegetation:– Tread tracking– Erosion blankets/mats– Mulching

Phasing, Seeding, Mulching, and Other Erosion Prevention Measures

• Clearly specify project phases in SWPPP– Phasing is more common with larger

sites (e.g., 3 to 5 acres or more)– For example, commercial building site /

parking lots / landscaped areas

• Standard notes should indicate:– Grading should be completed as soon

as possible after clearing and grubbing– Graded areas to be stabilized within 14

days

What are the BMP selection criteria?

• Must minimize degradation of downslope creeks, rivers, streams, wetlands, lakes

• Must protect waterway uses• Must be based on site-specific conditions• Must effectively minimize discharges for

storms < 2 year, 24 hour rain• Must have goal of 80% reduction of total

suspended solids that exceed predevelopment levels

• Should minimize post-construction runoff

Specific documentation requirements

• Describe plan to minimize disturbance and period of time areas are exposed

• Minimize overall area of disturbance

• Phase construction activities

• Schedule clearing & grading to avoid heavy rainfall

Entering Management Practice Information on the SWPPP

• SWPPP format is not specified by KDOW– For small sites, can enter

all information on plan sheet

– For larger sites, a narrative plan plus plan sheets are recommended

Updating the SWPPP

• SWPPPs must be revised:– Whenever stormwater controls are

“significantly” modified– If existing controls are “ineffective in

eliminating or significantly minimizing pollutants” in discharges

• Modifications to SWPPP shall be made within 7 calendar days after inspection

• Revisions to be implemented before next storm event whenever practicable; must document!

Signature on SWPPP

• SWPPP must be signed by:– Responsible corporate officer– Authorized manager– Business proprietor or partner– Government executive– Permittee representative

authorized (in writing) by one of the above

SWPPP availability

• SWPPP must be current and “readily available”

• Person with day-to-day operational control must have SWPPP when on the site

• If SWPPP is not on site, location must be posted near main entrance to site

• SWPPPs must be made available to KDOW, USEPA, other federal/local governments & their contractors

Inspection requirements

• Two options for inspections:– At least once every seven

calendar days– At least once every 14 calendar

days, and within 24 hours after 0.5 inches of precipitation

• Areas with temporary/final stabilization inspected once per month

• KDOW recommends “walk through” inspections of sites before storms

KPDES permit inspector requirements

• Inspections shall be

performed by

“knowledgeable and

skilled” personnel

• Inspectors “shall have training . . . such as KEPSC, CPESC, CPSWQ, TNEPSC, CESSWI, or other similar training”

Inspection requirements for SWPPP

• Must visually inspect erosion, sediment, & housekeeping measures to determine if:– They are properly installed, maintained, &

working effectively– Excessive pollutants are entering the

drainage system

• Must also inspect disturbed areas, site exits, material storage areas, runoff discharge locations, receiving waters (or downstream areas)

Linear project inspections

• Can conduct representative inspections

• Includes 0.25 miles above & below intersections with roads, right-of-ways, and other features

Written inspection reports include:

• Date of inspection

• Name and title of inspector

• Synopsis of weather since last inspection– Time & duration of storm events– Approximate amount of rainfall

• Weather conditions & discharges during inspection

• Location of sediment & other discharges

Written inspection reports include:

• Location of sediment, erosion, and other control measures requiring maintenance

• Location of stormwater control measures that failed to operate or proved inadequate

• Locations where additional control measures are needed

Inspection report requirements

• Identify actions taken in response to inspection findings

• Identify any incidents of non-compliance with the SWPPP

• If no non-compliance actions, must certify that site is in compliance with SWPPP

• Inspection reports must be signed kept with SWPPP

Who signs the inspection report?

• Responsible corporate officer

• Authorized manager• Business proprietor or

partner• Government executive• Permittee representative

authorized (in writing) by one of the above

Inspection report certification

"I certify under penalty of law that this document and all attachments were prepared under my direction or supervision in accordance with a system designed to assure that qualified personnel properly gather and evaluate the information submitted. Based on my inquiry of the person or persons who manage the system, or those persons directly responsible for gathering the information, the information submitted is, to the best of my knowledge and belief, true, accurate, and complete. I am aware that there are significant penalties for submitting false information, including the possibility of fine and imprisonment for knowing violations."

Stabilization requirements

• Temporary stabilization required on portions of the site where construction activities have temporarily ceased shall be initiated within 14 days

• Final stabilization also required within 14 days after permanently ceasing work

• Final stabilization required if work is suspended for more than 180 days

Final stabilization means:

• All soil disturbing activities have been completed and:– a uniform (e.g., evenly distributed, without large bare areas)

perennial vegetative cover with a density of 70 percent on all unpaved areas and areas not covered by permanent structures, or

– equivalent stabilization measures (such as the use of riprap, gabions, or geotextiles) have been employed

• For individual lots in residential construction: – Final stabilization completed as specified above, or– Temporary stabilization including perimeter controls for an

individual lot prior to occupation of the home by the homeowner and informing the homeowner of the need for, and benefits of, final stabilization.

• For construction projects on ag land, final stabilization may be accomplished by returning the disturbed land to its preconstruction agricultural uses– Areas disturbed that were not previously used for agricultural

activities, such as buffer strips immediately adjacent to waters of the Commonwealth and areas which are not being returned to their preconstruction agricultural use must meet the final stabilization criteria above