Gas transmission lines from permitting to...

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Gas transmission lines: Gas transmission lines: from permitting to from permitting to constructionconstructionTips and suggestions on plan design and field Tips and suggestions on plan design and field implementationimplementation

By Chris DrosteBy Chris DrosteSenior Erosion Control SpecialistSenior Erosion Control SpecialistWestmoreland Conservation District March 15, 2012Westmoreland Conservation District March 15, 2012

Permits required with gas Permits required with gas transmission linestransmission lines Erosion Control plans required for Erosion Control plans required for

disturbance UNDER 5 acres. disturbance UNDER 5 acres. ESCGPESCGP--1 required for disturbance 1 required for disturbance

OVER 5 acres.OVER 5 acres. Chapter 105 General permits are Chapter 105 General permits are

required for stream crossing with required for stream crossing with access roads and utility lines.access roads and utility lines.

Municipality may require bonding, Municipality may require bonding, grading or land disturbance permits. grading or land disturbance permits.

General Criteria for the General Criteria for the ESCGPESCGP--11 $500.00 permit fee $500.00 permit fee (payable to Wm CWF)(payable to Wm CWF)

$100.00 per disturbed acre fee $100.00 per disturbed acre fee (payable to PA CWF)(payable to PA CWF)

On large multiOn large multi--county transmission county transmission lines, DEP issues the permit, lines, DEP issues the permit, conservation districts review the E&S conservation districts review the E&S plans.plans.

Specifics to the ESCGPSpecifics to the ESCGP--11

NOI checklist should be filled out and NOI checklist should be filled out and all items included in the plan narrative all items included in the plan narrative and drawings.and drawings.

Important: Please fill out new, Important: Please fill out new, renewal, major or minor revision. renewal, major or minor revision.

Include phasing if pipeline will extend Include phasing if pipeline will extend over time.over time.

A PPC plan is requiredA PPC plan is required

Specifics Cont.Specifics Cont.

Site restoration plan needs to be Site restoration plan needs to be explained on page 3 of NOI.explained on page 3 of NOI.

PCSM forms must be completed (even PCSM forms must be completed (even if you have no permanent impacts). if you have no permanent impacts).

Section E: special protection watersSection E: special protection waters–– Check the boxes that apply: Use the Check the boxes that apply: Use the

various BMPvarious BMP’’s listed for site restoration s listed for site restoration and access road construction.and access road construction.

Document you will see from DEP when you Document you will see from DEP when you receive approvalreceive approval

Chapter 105Chapter 105General permits for stream General permits for stream crossingscrossings

Which GPWhich GP’’s pertain to my project?s pertain to my project?

GPGP-- 5 and GP5 and GP--88

General Permit (GPGeneral Permit (GP--5) is required for 5) is required for crossing the stream with the crossing the stream with the transmission line.transmission line.

General Permit (GPGeneral Permit (GP--8) is required for 8) is required for temporary access across the stream temporary access across the stream with equipment.with equipment.

GPGP--5 timeframes5 timeframes

–– Minor crossings to be completed within Minor crossings to be completed within 24hrs start to finish including:24hrs start to finish including: Opening the trenchOpening the trench Line installation and backfillLine installation and backfill Stabilization of area with Riprap or Turf Stabilization of area with Riprap or Turf

reinforcement matreinforcement mat

GPGP--5 Timeframes5 Timeframes

Major stream channels < 100Major stream channels < 100’’ wide need to wide need to be completed within 48 hrs. be completed within 48 hrs.

Extended time must be approved by DEP or Extended time must be approved by DEP or Conservation District.Conservation District.

Timber mats or pads should be used if Timber mats or pads should be used if crossing wetland areas.crossing wetland areas.

Do not use soil as a coffer dam for a pump Do not use soil as a coffer dam for a pump around system.around system.

Horizontal Directional Drilling requires GPHorizontal Directional Drilling requires GP--55

DO NOT place soil in the streamas the coffer dam

Use a jersey barrier or sandbag dam

General Fluming of the stream

Setting pipeline to proper depth beneath the stream is important.

Horizontal Direction Horizontal Direction Drilling (HDD)Drilling (HDD)

HDDHDD

Used in sensitive areas (HQ/EV watersheds) Used in sensitive areas (HQ/EV watersheds) ABACT control methodABACT control method

Recommended when drainage area Recommended when drainage area (DA)>50 sq/miles(DA)>50 sq/miles

DownsidesDownsides–– Drilling mud Drilling mud –– Volume of drilling mud overwhelming ability to Volume of drilling mud overwhelming ability to

remove it from siteremove it from site–– Chemicals added to drilling mud need to be Chemicals added to drilling mud need to be

removed from site and taken to facility.removed from site and taken to facility.

HDDHDD

Dry material from entry and exit pit Dry material from entry and exit pit must be stockpiled out of floodway must be stockpiled out of floodway

E&S BMPE&S BMP’’s need to be designed for s need to be designed for both pit areas.both pit areas.

FracFrac--outs can be a problem with outs can be a problem with discharge of drilling mud if geologic discharge of drilling mud if geologic conditions exist.conditions exist.

Temporary Access Road Temporary Access Road Crossing of the StreamCrossing of the Stream

General Permit 8General Permit 8

Temporary Road Crossing permitTemporary Road Crossing permit Obtained through Delegated Obtained through Delegated

Conservation District or DEP regional Conservation District or DEP regional office.office.

Crossing permits are good for 1 yearCrossing permits are good for 1 year Roads must cross all watercourses at a Roads must cross all watercourses at a

right angle.right angle.

General Permit 8General Permit 8

Pipes must be sized appropriately Pipes must be sized appropriately and extend beyond the toe of the and extend beyond the toe of the roadway fill.roadway fill.

Clean rock fill must be used (NOT Clean rock fill must be used (NOT streambed material).streambed material).

Cover over pipe must not exceed Cover over pipe must not exceed the minimum required by the pipe the minimum required by the pipe manufacturer. manufacturer.

General Permit 8General Permit 8

Regular maintenance should be Regular maintenance should be performed in order to keep pipes free performed in order to keep pipes free of debris or other obstructions.of debris or other obstructions.

Not authorized in trout stocked Not authorized in trout stocked streams between March 1 and streams between March 1 and June 15.June 15.

Using timber bridgesUsing timber bridges

Temporary timber bridges can be used Temporary timber bridges can be used in lieu of pipes. in lieu of pipes.

Must pass the bank full flow and Must pass the bank full flow and normal flow and not create a dam.normal flow and not create a dam.

Timber bridges should have side skirts Timber bridges should have side skirts to keep mud from tires from entering to keep mud from tires from entering stream.stream.

Mud needs to be scraped off daily Mud needs to be scraped off daily from bridge.from bridge.

Wood side skirts were installed here to keep silt out

Timber bridges for stream crossingsTimber bridges for stream crossings

Portable bridges across flood channels can be used to span the waterway

Pipe CrossingsPipe Crossings

F IG U R E 2 6 – Te m porary S tre am C rossing D eta ils

A n 8” th ick layer o f A A S H TO # 1 s tone shall be m ain ta ined for a m in im um d is tance of 50 ’ from top o f ba nk on bo th s ides o f s tream channel.

Problems with crossings

1. Fill over pipes is too high (4-5 feet)2. Fill is not Clean Rock3. Pipes are directing flow into stream bank causing erosion4. Crossing is not depressed as to allow overflow of water

Rock is level and not depressed enough

Designing the E&S plan Designing the E&S plan for the corridorsfor the corridors

Design suggestions Design suggestions

Design a time frame sequence from initial Design a time frame sequence from initial clearing and grubbing to the final clearing and grubbing to the final stabilization.stabilization.

Minimize the rightMinimize the right--ofof--way disturbance way disturbance required to construct the transmission line.required to construct the transmission line.

Show the corridor and any access roads to Show the corridor and any access roads to the pipelines on topographical maps.the pipelines on topographical maps.

Locate all stream crossings on the Locate all stream crossings on the topographical maps with a numbering topographical maps with a numbering system that corresponds to the details page. system that corresponds to the details page.

Design suggestionsDesign suggestions

Design charts for flume sizes for each Design charts for flume sizes for each crossing help the contractor know crossing help the contractor know what size pipe is needed.what size pipe is needed.

Specify trench plugs at stream Specify trench plugs at stream crossings and on steep slopes. crossings and on steep slopes. –– Sand filled sacks or spray foam Sand filled sacks or spray foam

technology can be used.technology can be used.

Include a visual inspection checklist for Include a visual inspection checklist for inspectors in the field to monitor inspectors in the field to monitor controls.controls.

Design suggestionsDesign suggestions

Trench plugsTrench plugs-- spray foam spray foam typetype

Provides good adhesion to the surface

PipePipe--yards yards

PipePipe--yard issuesyard issues

Pipe yards can be sources of large Pipe yards can be sources of large disturbances that need erosion controls.disturbances that need erosion controls.

Plans should address the disturbance. Plans should address the disturbance. Assume total area will be disturbed Assume total area will be disturbed -- some some exceed 5 acres!exceed 5 acres!

NPDES permits may be required for these NPDES permits may be required for these sites. sites.

Silt fence may not always work, sediment Silt fence may not always work, sediment traps and collection channels may be traps and collection channels may be required.required.

PipePipe--yardsyards

PipePipe--yardsyards

All situations are different, but planning is important

A stable surface should be part of the pipe yard plan.

Access Roads Access Roads

Access Roads to the Access Roads to the pipeline corridorpipeline corridor Sometimes roads need to be installed to get Sometimes roads need to be installed to get

materials to the site.materials to the site. Temporary roads will need controls until the area is Temporary roads will need controls until the area is

restored back to original condition.restored back to original condition. Permanent roads may need controls such as Permanent roads may need controls such as

detention swales, turnouts, crossdetention swales, turnouts, cross--culverts. culverts. You can use design standards from the new E&S You can use design standards from the new E&S

manual for road construction. manual for road construction. LayLay--down areas should have appropriate designed down areas should have appropriate designed

controls, silt fencing, silt sock traps, rocked controls, silt fencing, silt sock traps, rocked entrances and haul roads.entrances and haul roads.

Show the access roads on the Show the access roads on the plans plans

Access roads become point sources.Runoff needs control with water bars, turn-outs,or cross culverts to rock dissipaters.

Cross drain culvert chartCross drain culvert chart

Design aids in new E&S ManualDesign aids in new E&S Manual

Designing the controls Designing the controls for the pipeline corridorfor the pipeline corridor

What controls are typically used on What controls are typically used on pipeline projects?pipeline projects?

Using silt fence and Using silt fence and compost sockscompost socks Silt fence and/or compost filter socks are a Silt fence and/or compost filter socks are a

typical erosion control for this activity.typical erosion control for this activity. Place along the corridor sides, below soil Place along the corridor sides, below soil

stockpiles, and at stream crossings. stockpiles, and at stream crossings. Use proper slope % and distance Use proper slope % and distance

calculations for appropriate size.calculations for appropriate size. Do not use in concentrated flow areas such Do not use in concentrated flow areas such

as channels or ends of water bars. Use rock as channels or ends of water bars. Use rock filter outlets.filter outlets.

Design the fence to catch corners of the corridor and stockpile locations

Rock filter outletlocation

Concentrated areas of drainage points need relief with Rock Filter outlets

Concentrated runoff

The sediment has flowed under and around the hay bales.

A rock filter or compost sock trap is the best alternative here

Compost sock pyramid Compost sock pyramid stacks.stacks.

- Pyramid stacking of sockscan allow more buildupof sediment.

- Traps can be constructed with this configuration and installed in tight areas.

Designing a pyramid sediment trap can be useful when concentrated flow areas exist and normal socks cannot handle the flow.

Compost socksCompost socks

Butt the socks together and install chips behind the sock to trap water.

Crossing controlsCrossing controls

Socks can be used to drape across the bridge

Install silt fence at each side of the crossing

WaterbarsWaterbars

Water bar/ broadWater bar/ broad--based based dip detailsdip details

Install temporary water Install temporary water bars after clearing corridor bars after clearing corridor

Water bar use before pipe is Water bar use before pipe is installedinstalled

Long corridor runs should have water bars even at flatter 2% slopes.Concentrated water can build speed and blow out silt fence.

Water bars should be installed to divert slope water.

Topsoil piles used for Topsoil piles used for containment berms containment berms

Topsoil stripped and stockpiled in linear fashion can be placed on downhillslope of corridor to act as a containment berm.

Steep sectionsSteep sections

Containment berms are best on these steep sections.

Rock filter outletRock filter outlet

Extend the crossing pipesExtend the crossing pipes

Cross pipes for access roads should be extended past disturbed areas.

Roadway crossings and Roadway crossings and encountering municipal encountering municipal drainage swales drainage swales

Stabilizing drainage Stabilizing drainage swalesswales Any Any stormwaterstormwater swales that are swales that are

impacted during the line installation impacted during the line installation should be reconstructed and lined with should be reconstructed and lined with a suitable TRM mat or ripa suitable TRM mat or rip--rap.rap.

A temporary diversion byA temporary diversion by--pass should pass should be installed until the channel is rebe installed until the channel is re--constructed to reduce any washout constructed to reduce any washout and sedimentation to the stream and sedimentation to the stream below.below.

A Storm water channel disturbed by activities

Flow path

The swale was created here and rocked with R-3 and R-4.

The areas around the swale were seeded and mulched.

1 month later-- the areas are stable and back to normal.

Contractors should avoid disturbing roadside swalesContractors should avoid disturbing roadside swales

Protect critical drainage Protect critical drainage inlets inlets

Utilize the wire mesh and stone type inlet protection

Inlet protection details Inlet protection details from E&S manualfrom E&S manual

What can you do if you encountera municipal storm sewer outlet?

Typically you want to size the crosspipe according to outlet pipe size.

Road Crossings with Road Crossings with PipelinesPipelines

Cross pipes, approaches, and Cross pipes, approaches, and restoration of swalesrestoration of swales

Roadway crossingsRoadway crossings

Upslope runoff needs diversion with water Upslope runoff needs diversion with water bars to prevent runoff to road.bars to prevent runoff to road.

Silt barriers need to be located down slope Silt barriers need to be located down slope of bore pit or bore pit storage piles.of bore pit or bore pit storage piles.

Locate storage piles need away from road Locate storage piles need away from road swale or inlets or floodway of stream.swale or inlets or floodway of stream.

Roadway crossingsRoadway crossings

Roadway water should bypass disturbed Roadway water should bypass disturbed areas with use of properly designed cross areas with use of properly designed cross pipes.pipes.

Watch for all utility lines with designing bore Watch for all utility lines with designing bore pit locations. pit locations.

Specific details should be shown in the plan Specific details should be shown in the plan for each crossing.for each crossing.

Steep areas draining to roadwaysSteep areas draining to roadways

Diverting the water on steep slope areas is critical.

Access road crossing roadside Access road crossing roadside channelchannel

pipeRock fill

Swale Restoration requiredSwale Restoration required

In the design of the plan, include provisions to restore the channel.

Shoulder was cut back and will need R-3 or larger to control erosionThe bank will need blanket due to steepness.

Provide some detailson swale reconstructionfor contractor.

Use Swale design details and charts Use Swale design details and charts in your plansin your plans

Riprap sizing charts

Stabilizing the corridorsStabilizing the corridors

Seeding, mulching, and hydro Seeding, mulching, and hydro seeding seeding

What to show in the planWhat to show in the plan

Describe the methods you are using to Describe the methods you are using to stabilize the slopesstabilize the slopes–– Fertilizer rates and liming rates may increase for poor Fertilizer rates and liming rates may increase for poor

soils/acidic soils.soils/acidic soils.–– Be sensitive to agricultural areas, farmers may not want Be sensitive to agricultural areas, farmers may not want

typical grass planted. Tall fescue, Redtop, with Perennial typical grass planted. Tall fescue, Redtop, with Perennial Rye, Birdsfoot trefoil can be used.Rye, Birdsfoot trefoil can be used.

–– Strip mined areas Strip mined areas -- use the mine mix tables.use the mine mix tables.

Include a chart for seedmixes.

Hydro-mulching is a good stabilization method.

Contractors can use one vehicle to apply seed/fertilizer and mulch In one spray.

Blankets can be used in lieu of Riprapnear HQ/EV waterwaysfor ABACT methods.

Regular seeding and mulching is also an option.

Stream crossings

Problems with soil fertilityProblems with soil fertility

Topsoil applied Little Topsoil applied

Low PH problems

Acid Producing SoilsAcid Producing Soils

Excavations that encounter rock that Excavations that encounter rock that could produce acid drainage.could produce acid drainage.

Could be encountered when Could be encountered when performing HDD operations. performing HDD operations.

Websites to locate information Websites to locate information regarding these issues:regarding these issues:

Links to geologic acid soils Links to geologic acid soils informationinformation

http://www.dcnr.state.pa.us/topogeo/http://www.dcnr.state.pa.us/topogeo/openfile/acidmaplayers.aspx#2openfile/acidmaplayers.aspx#2

http://ngmdb.usgs.gov/Prodesc/proddhttp://ngmdb.usgs.gov/Prodesc/proddesc_73912.htmesc_73912.htm

http://pubs.usgs.gov/of/2005/1325/#http://pubs.usgs.gov/of/2005/1325/#PAPA

--Be sensitive to farmersBe sensitive to farmers’’ needsneeds--Grazing animals and cropping may be desired Grazing animals and cropping may be desired in areas.in areas.

Stabilization is required within 4 days of ceasing activity.

Temporary Winter stabilizationTemporary Winter stabilization

Blown straw mulch provides cover until permanent seed can be applied.

Questions?Questions?

Chris Chris DrosteDrostechris@wcdpa.comchris@wcdpa.com

724.837.5271, ext. 174724.837.5271, ext. 174

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