best management practices (bmp) · work that is not covered by the permit includes: "#...

Best Management Practices (BMP)

For Maintenance Activities

In and Around Streams

Introduction ublic concern about the environment, a commitment to environmental stewardship, environmental laws and regulations, and

a desire to increase operational efficiency are prompting state and local governments to mitigate, reduce and eliminate the environmental impacts of highway maintenance. At the same time, these agencies must remain focused on their fundamental mission of providing a safe driving condition, offering the level of service customer’s desire, and preserving the highway infrastructure. Public accountability also requires cost-effective use of public funds.

One major area of maintenance involves work in and around streams and rivers. Drainage structures and channels must be kept open and clear of debris to minimize the possibility of wash outs and

undermining of adjacent embankments. Additionally, emergency repairs to structures and roadway fills caused by flooding have to be accomplished to protect the integrity of the structure and the roadway. All these activities have the potential to damage streams and subsequently degrade the water quality through the action of erosion and sedimentation.

Photo 1: Division of Water personnel reviewing recent maintenance activity in a stream.

P

BMP for Maintenance Activities In and Around Streams

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This manual was developed to introduce the U.S. Army Corps of Engineer’s (USACE) general permit for highway maintenance in Kentucky and to give the engineer and maintenance personnel practical guidelines on Best Management Practices (BMP) when performing activities in and around streams. These guidelines are not intended to be the only solutions but have proven to work in the field. Where appropriate, practices intended to be a more permanent fix have been used. Agencies look more favorably on permitting stream work that provides a permanent solution rather than a temporary or expedient fix that may create more damage to the stream over the long term.1

Best management

practices in this guide were developed with the assistance of the USACE, Louisville District, Kentucky Department for Environmental Protection, Division of Water, Division of Waste Management, Division of Air Quality, and Districts 2, 5, 6, 9, and Central Office personnel of the Kentucky Transportation Cabinet, Department of Highways. The maintenance activities covered include:

!!!! Drift Removal from Bridges and Culverts !!!! Beaver Dams !!!! Stream Clean-out/Culvert Sediment Removal !!!! Embankment Repair and/or Protection !!!! Scour/Erosion and Miscellaneous Repairs to Bridge Elements !!!! Bridge and Culvert Replacement !!!! Erosion Control and Project Restoration !!!! Bioengineering

1 Transportation Research Board. NCHRP Synthesis 272. National Academy Press. Washington, D.C. 1999.

Photo 2: Newly installed gabion baskets


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This manual contains Kentucky’s new USACE General Permit No. 199900077 (see Appendix A). This permit covers in stream work associated with normal highway maintenance, repair, and replacement activities within blue line streams of the Commonwealth of Kentucky. Blue line streams are streams shown as a solid or dashed blue line on a USGS 7.5 topographic map. Work that is consistent with the limitations of the permit may be accomplished without further permitting or notice to the USACE or the Division of Water. If there are questions about the scope of a project, the Division of Water can review the planned work and determine if it is consistent with the permit. The General Permit is applicable to routine maintenance involving drift removal from bridges and culverts, stream clean out, embankment repair and counter-measures, scour and erosion repairs to bridge elements, and in-kind bridge and culvert replacement. No bulldozer work will be allowed.

This manual also contains the procedures to be followed in obtaining the necessary permits from the USACE and the Kentucky Division of Water, when more work is planned, than allowed under the General Permit No. 199900077.

Work that is not covered by the permit includes: "# Bulldozer work "# Work in the listed in “Outstanding Resource

Waters” "# Work limits within a stream reach greater than 200

feet "# Work which could not otherwise be accomplished

according to the conditions of the General Permit and requires a Water Quality Certification permit.


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For projects that are not covered by the USACE general permit, information must be submitted to the appropriate Corps District and to the Kentucky Division of Water, on the attached “Site Specific Project Sheet.” This form is part of the General Permit.

Innovative techniques are included in this guide. These techniques

are a more proactive approach to stream restoration. Use of these methods should be considered as ways to extend the life of the repairs and to reduce the stream impacts of the work.

The USACE General Permit for Highway Maintenance contains

special and general conditions that must be followed and a list of streams and waters, referred to as “Outstanding Resource Waters” (ORW), where work in these streams is not allowed by the permit. (see Appendix B).

Special conditions of the General Permit provide specific guidelines

to perform maintenance activities within the stream:

1. Stream impacts shall be limited to 200 linear feet of stream for each single and complete project.

2. Bulldozers shall not be used to perform any work within the

confines of the stream channel.

3. All work, except for emergency work, shall be performed during low flow conditions within the stream channel. “Emergency work” should be determined by the Transportation Engineering Branch Manager for Operations or the County Judge Executive, as applicable.

4. Only emergency work shall be performed within the confines of

the stream channel from April 15 through June 15.

5. Material removed from the channel or banks shall not be stockpiled overnight within the confines of the stream channel. All spoil material shall be loaded onto trucks and hauled away to upland sites, not to any wetland areas, for later use, storage, or disposal.

6. All necessary permits shall be obtained regarding appropriate


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disposal for debris or excavated material as listed in the attached “Coordinating Permit Contacts.”

7. Disturbance to the existing stream bank vegetation shall be

minimized. Where practicable, existing access roads into the stream channel shall be utilized to enter and exit the work area.

8. Removal of material from culvert or bridge openings shall be

limited to 100 feet upstream and downstream of the inlet or outlet of the structure. Material removed from bridge openings shall be limited to restoration of the original cross-section.

9. If work occurs within 2,000 feet upstream to 300 feet down-

stream of a public water supply intake operated by someone other than the permittee, the permittee shall provide signed agreements from the intake operator allowing the work to be conducted within the stream reach.

10. The work shall not occur in a stream listed in the attached

“Outstanding Resource Waters,” nor in a designated component of the National Wild and Scenic River system, or the State Wild and Scenic River System or in a Federal or State designated wildlife management area.

11. No activity shall destroy a threatened or endangered species, as

identified under the Endangered Species Act or amendments or endanger the critical habitat of such species, or occur in areas of concentrated shellfish production.

12. Any specific authorization granted by this General Permit is

subject to revocation or modification by the USACE’s District Engineer, if in his opinion, the activity so authorized is detrimental to the environment or is damaging to the general public interest.


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Chapter 1

Drift Removal from Bridges and Culverts

Drift consisting of trees logs garbage, tires and other debris that have become lodged at bridge piers, or in culvert opening must be removed.

$#Work during low flow

periods. $#Generally done by

placing a crane on the bridge deck or roadway and using a clam bucket to dip out the material.

$#Debris and silt can be

removed from large culverts by placing a small loader or bobcat directly in the culvert. The loader moves the debris and silt to the inlet or outlet where an excavator along the bank loads onto a truck for disposal.

$#A cable and winch can

be used to pull and remove large trees or logs from the stream.

Photo 3: Large debris rack against bridge.

Photo 4: Removing debris from top of bridge with crane and truck.


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$#Where available, long boom excavators may reach from the roadway to the streambed to remove the debris.

$ Personnel in the stream

can saw large logs into smaller, more manageable pieces, before they are removed.

$#When the streambed is

solid rock or is dry, a track loader and trucks can be placed in the streambed to remove and load the material onto trucks. Access points into the stream must be minimized to reduce the impact to the stream.

$#Disposal of the material may be accomplished by:

%#Burying near the site %#Burying away from the site %#Hauling the material to a permitted construction/demolition

landfill % Hauling the material to a permitted municipal solid waste

landfill

%#Burning the material.

A. On-Site Burial Burying near the site involves selecting an area that is in the right of way or on private property that can take the waste without creating a nuisance and can accommodate the waste. $#When the site is on private property and in the flood plain, the

Photo 5: White goods and other forms of

trash can be part of debris racks.


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landowner is required to obtain a flood plain permit from the Division of Water.

$#A consent release is required for use of private property. (see

Appendix C) $#Division of Waste Management regulations grants on-site burial

without a permit application (known as a permit-by-rule). These regulations allow burial of debris on property where the land clearing occurs.

$#The waste that is buried must be free of tires, trash (garbage),

containers (buckets), barrels (empty or not) and hazardous wastes. These wastes must be segregated and removed for disposal at appropriate disposal facilities.

$#When the site is completed, it should blend-in, the cover dirt should

be deep enough, shaped to be revegetated, and stay in place. B. Off-Site Burial Burying away from the site involves transport of the material from the project site. Multiple projects may be involved. When this method of disposal is selected, all of the requirements of burying near the site must be met. The site must be registered with the Division of Waste Management. There is a limit of one acre as the maximum size of the sites to be used in this manner. There is a five-day waiting period from the date of filing a registration to authorized use of the site. There are provisions in the Waste regulations that address emergencies when the project can not wait the five days. C. Landfill Disposal Waste can be removed and disposal at a permitted construction/demolition landfill. The Division of Waste Management based on site specific information permits these landfills. The considerations for this method involve handling the debris after it is removed from the site as well as costs for use of the landfill. These landfills have less stringent design and operating requirements than landfills that dispose of municipal solid waste. The waste hauled to


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these sites must be free from tires, trash (garbage), containers (buckets), barrels (empty or not) and hazardous wastes. These wastes must be segregated and removed for disposal at appropriate disposal facilities. D. Municipal Disposal Waste can be removed and disposed at a landfill permitted to dispose of municipal solid waste. The Division of Waste Management based on site specific information permits these landfills. The consideration for use of this method involves how to handle the debris after it is removed from the site as well as the costs for use of the landfill. These landfills have the most stringent design and operating requirements for disposal of solid waste. The waste hauled to these sites must be free of tires, containers (buckets) that are not empty, barrels that are not empty and hazardous wastes. These wastes must be segregated and removed for disposal at appropriate disposal facilities. E. Burning the Debris Burning may be practiced when it is appropriate to do so. The material that may be burned is the wood or limbs that drift to the project site. This wood should be relatively dry to burn and not create excessive smoke or particulate. The site selected for burning may be on the right of way or on private property. The site must be far enough away from highways to not create a hazard to the public. Smoke that may come from the burning must not obscure the vision of the traveling public.

Crews must be prepared to extinguish fires that cause a hazard or cannot be confined to the burn area. Personnel must be on site at all times while the fire is burning. The fire must be extinguished before personnel leave the site. Consent releases are required when the site is on private property. Use of extraneous materials such as tires or heavy oils, (which tend to produce dense smoke) to start or sustain burning, is prohibited. The Division of Air Quality and the local fire chief are to be notified. The Division of Forestry should be notified when applicable. All impacted property owners should sign consent release letters. Burning must be done on days when conditions do not pose a threat of igniting a forest fire. Burning during dates and times of banned burning will not be allowed. The debris to be burned must be free from tires, trash (garbage), containers (buckets), barrels (empty or not) and hazardous wastes. These wastes must be segregated and removed for


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disposal at the appropriate disposal facilities. Appendix D - contains a list of solid waste facilities and

construction/demolition debris landfills. The facilities addresses and contact numbers are also included in the list. An application for Registered Permit by Rule for Construction/Demolition Landfills of one acre or less is included.


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Chapter 2

Beaver Dams Removal of beaver dams is a part of routine maintenance, when water that backs up from a dam threatens to flood highways, railroads, or interferes with proper drainage and maintenance activities. The following guidance should be followed when breaching or removing beaver dams. $#Discharge from breach should not exceed the normal high flow of

the stream. $#The breach should be monitored until normal baseline flow has been

achieved. $#Properties located downstream must be inspected for flooding

potential from the breach before removing the dam. $#Water levels should be lowered gradually to prevent down-stream

flooding. $#Dam material should be removed from the site so the beaver will not

return to repair the dam. $#Follow the guidelines in the Drift Removal Section for guidance on

disposing of dam material.

Photo 6: Beaver dam under a bridge.


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Chapter 3

Stream Cleanout/Culvert Sediment Removal

Loose rock and sediment, which has deposited over time at culvert or bridge openings, must be removed. This sedimentation may cause misalignment of the stream at the structure inlet and erosion of the channel banks or roadway embankment. $#Removal of material from culvert or bridge openings shall be

limited to 100 feet upstream and downstream of inlet or outlet of the structure.

$#Wholesale stream channelization or channel deepening should not

be performed during a cleanout operation. $#Any other modification requires permission from the USACE. $#When it is feasible, the work should be done using equipment that

does not have to be in the stream. Placing a backhoe or Gradall excavator on the bank and removing the material blocking the flow of water to the structure generally does this work.

$#The type and number of equipment used in the stream should be

limited. Machinery not required to accomplish the work should be kept out of the stream.

$#Material that is removed is loaded onto trucks and hauled away. The

material should not be placed on the stream banks or in the floodway.

$#A track loader or bobcat can work directly in the stream. This

activity can be done on a solid rock or rocky streambed when the stream is completely dry.

$#Bulldozers may not be used in a streambed. $#Do not remove vegetation from along stream bank unless absolutely

necessary. Avoid removing large trees. Do not undercut banks. $#Seed and mulch the disturbed areas along the stream bank.


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Chapter 4

Embankment Repair and/or Countermeasures This type of maintenance activity is generally done to prevent any future erosion to embankments. Placing channel lining, gabion baskets, or railroad rails to repair roadway embankments are addressed in this chapter. $#Channel Lining is

generally dumped into the eroded area from trucks and arranged by a backhoe or Gradall situated on the roadway. If material dumped directly from a truck cause too much scattering of the rock, the backhoe may place the material one-bucket at a time into the eroded area. This material must be Class III (9 inch to 2 feet) channel lining or quarry shot rock as outlined in the Master Agreement (price contract for coarse aggregates).

When necessary a track or rubber-tire loader can be place directly into the stream to arrange the rock. This is done only on rock streambeds when there is little or no water in the channel.

$#Gabion Baskets may be assembled off or on the job site. Prior to

placement of baskets, a backhoe or Gradall removes the loose eroded material. A level bench is constructed to set the gabion baskets. Once set in place, the baskets are filled with channel lining and then tied together. This forms a retaining wall, which prevents further erosion, and sloughing of the roadway into the stream. When a rock streambed is present loaders may be used to assist this process. If job site conditions require equipment to be placed in the

Photo 7: The Culvert and road embankment

above requires repair/replacement.


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stream, the work must be conducted during dry or low flow stream conditions.

$#Movable concrete barrier walls can be used as a base in the

streambed to support the gabion baskets. These are set in place by a crane positioned on the roadway. Some preparation of the streambed is required to construct a level bench for the barrier walls. This is done with a track or rubber tire loader in the streambed. Barrier walls are placed on a rock streambed or installed during low or no-flow conditions.

$#Railroad (“T”) Rails

are often used to repair roadway slips adjacent to streams. The T-Rails is either driven into place by a crane, or placed in pre-drilled holes, drilled by a truck-mounted drill. In either case, the crane or drill should be normally to be placed on the roadway above the eroded or slip area whenever possible. Once the rails are in place, cribbing may be placed against the rails to form a retaining wall. If job site conditions require equipment to be placed in the stream, the work must be conducted during dry or low flow stream conditions.

$#Cast-In-Place Concrete Retaining Walls may be constructed

along the stream bank to stabilize or repair roadway embankment erosion. Concrete retaining walls are best suited for solid rock streambeds or streambeds that have been determined by engineering analysis to sufficiently support this type of wall. Excavation is required to attain a sound base for a concrete footing. This excavation may be completed by equipment positioned on the roadway. If job site conditions require equipment to be placed in the

Photo 8: Backfilling behind cribs and rails

using a backhoe.


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stream, the work must be conducted during dry or low stream conditions. The excavated material may be hauled away, or stockpiled outside the flood plain for future use as back-fill. A concrete footing is then constructed normally using timber forms. Once the footing is placed, formwork may be constructed and concrete poured to form the wall. The forms are then removed, loaded into trucks and hauled away from the job site. Upon completion of the wall, backfill material may be placed behind the wall to facilitate proper drainage. This material can be creek run or quarry run stone. Sound engineering practice should be adhered to in designing and constructing concrete retaining walls.

Photo 9: Forming for a cast-in-place concrete

wall.


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Chapter 5

Scour/Erosion and Miscellaneous Concrete Repairs to Bridge Elements

Counter measure consist of placing Channel lining, rip-rap or shot rock, or placing concrete to repair or stop scour activity around bridge and culvert footings, or other concrete repairs to bridge elements. $# Channel Lining is placed

around bridge elements or culvert footings by a backhoe or Gradall positioned on the roadway or bridge. If the boom will not reach the affected area, a loader may be placed in the stream to move the stone.

$# Concrete is sometimes

used to supplement the existing footing, or repair the eroded area. Employees on foot working in the stream do most of the concrete forming work. Concrete is usually placed via chutes from the concrete truck positioned on the roadway. Plywood formwork is placed and some minor hand excavation may be required prior to concrete placement. In extreme instances, excavation may be done by backhoe positioned in the streambed. All forming waste material should be hauled away by truck.

Photo 10: Major scour problem at the bridge.

The streambed has degraded resulting in severe pile exposure.


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$# During some repairs, a cofferdam is required to prevent flooding of the immediate work area. Placing excavated material (rock, silt, and/or sand) to form a dike around the work area often used. When excavated soil is used to build the dam, geo-textile fiber and rock must be placed over the structure it from protect erosion. Water from the cofferdam must be pumped into a silt trap. (see Appendix E) When the work is completed, this material can be removed and hauled away or used as backfill around the structure. Other types of cofferdams include concrete barriers, plastic barriers, or a combination of all the above.

$# If job site conditions

require equipment to be placed in the stream, the work must be conducted during dry or low flow stream conditions.

$# When building a

cofferdam, a temporary rock platform must be used to support the equipment during construction.

$#If job site conditions require equipment to be placed in the stream,

the work must be conducted during dry or low flow stream conditions.

Photo 11: Approach Apron in need of repair.

Photo 12: Cofferdam used in construction.


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Chapter 6

Bridge and Culvert Replacement This type of replacement involves removing and replacing an existing pipe, culvert, or bridge with a similar type and size structure on a blue line streams. $#Work during low flow

periods. $#The work is performed

by removing the existing structure with equipment such as backhoe, Gradall, loader, and hoe-ram. A crane can also be used while positioned on the roadway. The material removed is loaded onto trucks and hauled away. All demolition material must be removed in a timely matter. The broken concrete can be reused as riprap. If the structure is dropped into the stream, excavation of the material is required. This excavated material can be hauled away or temporarily stockpiled out of the floodway for later reuse as backfill. When excavation is completed, the new structure is built in place, or delivered to the site and placed by crane into the prepared area. The structure can be backfilled with crushed rock or creek rock taken from the stream within the project limits. All work in the stream must be minimized. Stream crossing when required to facilitate detours must be designed according to Appendix F.

Photo 13: A bridge in the process of being

replaced.


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Chapter 7

Erosion Control and Project Restoration

Erosion is the process of separating and transporting soil away from its base by water or wind. Maintenance activities can promote erosion if not properly handled. Grading and sloping efforts for highway drainage within right-of-way should consider the effects of storm water runoff, and the potential to carry sediment loads to streams and rivers. Temporary control measures must include proper planning and installation of silt fences, straw bales, gently sloping terraces, temporary vegetative cover and/or fiber netting. Wheel tracks should not be left to initiate erosion activity. Runoff can carry soil into stormwater inlets, retention ponds, and other bodies of water causing sediment build-up, which reduces storage and flow capacity. Costly dredging at regular intervals of these structures would be required. Excessive deposits of silt and sediment can also smother and kill aquatic organisms. Sediment control structures should not be placed in the stream. The smallest practical work zone should be cleared to minimize erosion. Where feasible, any and all existing vegetation should be retained and not disturbed. Only work that is needed should be performed. Appendix G (a) Vegetating and Mulching Denuded Areas: Disturbed soils should

be seeded and mulched as soon as possible. Once established, seedlings can help retain soil in place and resist erosion. Temporary vegetation can provide immediate ground cover until permanent landscaping is in place.

(b) Diverting Runoff from Denuded Areas: Perimeter dikes or

ditches may be constructed to collect and route runoff to a protected outlet before reaching a maintained structure or stream.

(c) Minimize the Length and Steepness of Slopes: The longer and

steeper a slope, the greater the potential for erosion. Terraces, narrow and level plains placed at regular intervals can slow runoff and provide a place for sediment to settle. Benches and ditches are sometimes placed to intercept runoff and control flow before erosion occurs. Channels are sometimes lined with fabric


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or other materials to prevent erosion inside the channel. (d) Maintaining Low Runoff Velocities: Drainage channel velocities

may be controlled by channels lined with vegetation, riprapped, or by placing check dams at regular intervals. Establishing vegetation and minimizing slope lengths and steepness are effective means of controlling the flow of water. On disturbed areas, construction operators can drive equipment in a perpendicular direction to the flow of water to create track marks that interrupt the flow of water.

(e) Trapping Sediment On-Site: Sediment barriers can prevent eroded

soil from leaving work sites. Typical barriers include straw bale dikes, earthen berms, and silt fence. Heavy nylon matting that is capable of holding soil in place on steep slopes can be used while providing sufficient open space for grass seed to germinate.

(f) Native grasses and plants should be used in reseeding and planting

to reestablish the surrounding vegetation.2

2 Transportation Research Board. NCHRP Synthesis 272. National Academy Press. Washington, D.C. 1999.


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Chapter 8

Bioengineering

Bioengineering is combining living and inert non-living materials native to the water shed to provide soil reinforcement, prevent erosion, and restore the stream to create a stable, dynamic channel that maintains the biological diversity found in healthy Kentucky streams.

Bioengineering can produce restored streams that are more natural and provide better aquatic habitat than the typical engineered channels. These restored streams are designed based upon naturally occurring processes in order to have a more stable natural channel. The design incorporates the hydrology of the watershed and the hydraulics of the natural channel to design stable stream channel features.

Photo 14: This bioengineering method uses live

stake cuttings to revegetate and restore the stream bank.

Photo 15: An "engineered" stream restored the

old fashion way.


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A natural channel should not require any maintenance. Bioengineering has some disadvantages. A cookbook approach cannot be used. Training and experience are a requirement. Different design approaches work better in different watersheds and for different flow conditions. The design concept is not as universally accepted as engineering formulas.

Bioengineering must be site specific. Existing vegetation must be

retained whenever possible. The area of disturbance must be limited. Erosion must be minimized by protecting topsoil and over burden stockpiles. The excess water flowing through the construction site must be properly maintained. Native plants and rocks must be incorporated into the design.3

Several typical bioengineering standard drawings have been placed in

Appendix G. These drawings show installation of root wads, step pools, cross vanes, boulder drops, and other applications. These innovative techniques can be applied to various stream restoration jobs. The approach represents a more proactive approach to stream restoration.

3 Biohabitats, Inc., Natural Stream Channel Design for Kentucky Department of Transportation. Biohabitats, Inc. Towson, Maryland. July, 1998.

Photo 16: A successful installation of a root

wad.

Best Management Practices For Maintenance Activities In and Around Streams

Appendix A

U.S. Army Corps of Engineers DRAFT Permit


Appendix B

Outstanding Resource Waters (ORW)

Outstanding Resource Waters (ORW’s) are streams designated by the Commonwealth of Kentucky, Natural Resources and Environmental Protection Cabinet.

This list has been reorganized by District within the Transportation Cabinet to facilitate identification of

those areas that are excluded by the general permit for highway maintenance in Kentucky.

This list should be routinely verified with the Division of Water for updates.

This listing is from the internet web site: http://www.lrl.usace.army.mil/orf/nw/kywaters.xls


Appendix C

Consent Release


Appendix D

Solid Waste Facility List and Contact Numbers

and

Application for Registered Permit by Rule for Construction/Demolition Landfill of one acre or less


Appendix E

Silt Trap Standard Drawing


Appendix F

Stream Crossings


Appendix G

Silt Checks and

Temporary Silt Fences


Appendix H

Bioengineering Standard Drawings From Biohabitats, Inc.

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