DEG Executive CommitteePresident, Tom J. Temples

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Standing Committee ChairsContinuing Education, TBD

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Convention-Annual Meeting 2013 Pittsburgh,Kristin M. Carter and Danielle Deemer

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VOLUME 20 • NUMBER 2 • JUNE 2013

C O N T E N T S

Characterization of near-surface fractures for hydrogeological studies using azimuthal resistivity survey: A case history from the Mamu Formation, Enugu (Nigeria)Ahamefula U. Utom, Benard I. Odoh, Daniel K. Amogu, Amobi C. Ekwe, and Boniface C. E. Egboka . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Wetland and stream mitigation: Application of a resource condition assessment protocol in the Pennsylvania Marcellus ShaleDave Goerman, Russ Krauss, Dheepa Jayakumar, and Mark Bernstein . . . . . . . . . 53

Images are of stream reaches in optimal condition from various landscape positionslocated in South Central Pennsylvania. Background: Near Pristine HeadwaterComplex. Upper Left: Optimal forested Mainstem Reach. Lower Right: Optimalforested Headwater Reach. See related article beginning on page 53. Photos courtesy ofDave Goerman.

O N T H E C OV E R

Staff Editors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiPresident’s Column . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iiiInstructions to Authors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv2013 AAPG Annual Convention - DEG Abstracts . . . . . . . . . . . . . . . . . . . . . . . . . 63

R E G U L A R F E AT U R E S

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The Environmental Geosciences (ISSN 1075-9565) is published quarterly by the AmericanAssociation of Petroleum Geologists Division ofEnvironmental Geosciences. Offices are locatedat 1444 South Boulder Avenue, Tulsa, Oklahoma74119-3604. Copyright © 2013 by the AmericanAssociation of Petroleum Geologists Division ofEnvironmental Geosciences. All rights reserved.Phone (918) 584-2555, fax (918) 560-2694, e-mail: degjournal@aapg.org.

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EDITOR-IN-CHIEFKristin M. Carter

Bureau of Topographic &Geologic Survey

Pittsburgh, Pennsylvania, USA

MANAGING EDITORDanielle L. Deemer

Talisman USAWarrendale,

Pennsylvania, USA

SPECIAL ISSUES EDITORMichele L. CooneyAllegheny College,

Pennsylvania Geological Survey Pittsburgh, Pennsylvania, USA

ii

ASSOCIATE EDITORSUSA

Brannon Andersen, Furman University, Greenville, South CarolinaGregory A. Ayres, Penn E&R, Inc., Warrendale, PennsylvaniaDavid M. Bush, University of West Georgia, Carrollton, GeorgiaJoseph Donovan, West Virginia University, Morgantown, West VirginiaLee C. Gerhard, Thomasson Partner Associates, Lawrence, KansasErich D. Guy, US Army Corp. of Engineers, Huntington, West VirginiaPaul Hudak, University of North Texas, Denton, TexasSarah Kruse, University of South Florida, Tampa, FloridaJane S. McColloch, West Virginia Geological and Economic Survey, Morgantown, West VirginiaWilliam G. Murray, URS Corporation, Forth Washington, PennsylvaniaCynthia Murray Gulde, Chevron Energy Technology Co., Houston, TexasRachel O’Brien, Allegheny College, Meadville, PennsylvaniaRima V. Petrossian, Texas Water Development Board, Austin, TexasViola Rawn-Schatzinger, NETL-USDOE, Tulsa, OklahomaJanet S. Roemmel, A&R Resources, LLC, Salt Lake City, UtahJoseph Rossabi, Redox-Tech, Cary, North CarolinaLaura Sanders, Northeastern Illinois University, Chicago, IllinoisDibyendu Sarkar, Montclair State University, Montclair, New JerseyHenry I. Snider, Eastern Connecticut State University, Willimantic, ConnecticutGary Weissmann, University of New Mexico, Albuquerque, New MexicoThomas G. Whitfield, Pennsylvania Geological Survey, Middleton, PennsylvaniaRobert S. Young, Western Carolina University, Cullowhee, North Carolina

AFRICATheo C. Davies, University of Venda for Science and Technology, Limpopo Province, Republicof South Africa

ASIA/PACIFICXinbin Feng, Chinese Academy of Science, Guiyang, ChinaSunderrajan Krishnan, Carewater, Gujarat, IndiaN. Subba Rao, Andra University, Viskhapatham, India

CANADAMatthias Grobe, Alberta Energy and Utilities Board/Alberta Geological Survey, Edmonton,Alberta, Canada

EUROPEPeter M. Lloyd, Consultant, Falicon, Alpes Maritimes, France

LATIN AMERICAAderbal C. Correa, Texas Tech University, Lubbock, Texas, USA

MIDDLE EASTHaluk Akgun, Middle East Technical University, Ankara, Turkey

iii

April 28, 2013

Division of Environmental Geosciences

Welcome to the June issue of Environmental Geosciences. This issue includes an article on the resistivity-basedmapping techniques used in Nigeria. It is great to see articles from our international members in the journal.The authors discuss the methods used to map fractures in the near-surface Mamu Formation to aid in the identification of drill sites for better-yielding water wells.

The second article looks at the application of resource assessment protocols for wetland and stream mitigationin the Marcellus shale in Pennsylvania. The article outlines methods to assess impacts of oil and gas activitieson the environment. The protocol was developed by the Pennsylvania Department of Environmental Protectionand builds on previous work by the U.S. Army Corps of Engineers and the Virginia Department of EnvironmentalQuality. This work should be of great interest to our readers working in shale resource plays.

Also included in this issue are abstracts for DEG oral and poster presentations given at the ACE in Pittsburgh inMay 2013. As always, if you have an article that the readers of Environmental Geosciences would enjoy, orknow someone who does, send them along to our editorial staff. Thank you.

Sincerely,

Tom J. Temples, PresidentDivision of Environmental Geosciences

AUTHORS

Dave Goerman � 400 Market Street 3rd FloorRachel Carson State Office Building Harrisburg,Pennsylvania 17101; dgoerman@pa.gov

David S. Goerman, Jr., is a water pollution biologistat the Pennsylvania Department of EnvironmentalProtection in the Division of Wetlands, Encroach-ments, and Training, Bureau of Waterways Engi-neering and Wetlands. He is responsible for pro-viding permitting and technical expertise on issuesinvolving waterways, wetlands, floodplains, andstormwater management. Goerman earned a B.S.degree in the biological sciences from Clarion

Wetland and stream mitigation:Application of a resourcecondition assessmentprotocol in the PennsylvaniaMarcellus ShaleDave Goerman, Russ Krauss, Dheepa Jayakumar, andMark Bernstein

University.

Russ Krauss � Resource Environmental Solu-tions, LLC 5020 Montrose Boulevard, Suite 201Houston, Texas 77006; russ@res.us

Russell F. Krauss is the vice president of marketingand analysis at Resource Environmental Solutions,LLC. He holds a B.A. degree in geology fromBoston University and an MBA degree from theUniversity of Houston. Krauss is the Secretary–Board of Directors and Chair, Marketing Committee,at the National Mitigation Banking Association.

Dheepa Jayakumar � Resource EnvironmentalSolutions, LLC 5020 Montrose Blvd., Suite 201Houston, Texas 77006; dheepa@res.us

Dheepa Jayakumar is a regional program man-ager at Resource Environmental Solutions, LLC.She earned a B.S. degree in biology from HoustonBaptist University, an M.S. degree in financeand a graduate real estate certificate from theUniversity of Houston.

Mark Bernstein � Resource EnvironmentalSolutions, LLC 643 Magazine St., Suite 301 NewOrleans, Louisiana 70130; mark@res.us

Mark Bernstein is a development analyst at Re-

ABSTRACT

With the exploration and the production of the Marcellus Shalecome inevitable unavoidable environmental impacts to the surfaceof the Earth and associated waters of the United States includingwetlands and streams. Environmental impact assessment includesmeasurement of impacts to aquatic resources, much of which is as-sociated with the production and transportation of Marcellus Shalegas to market. The Commonwealth of Pennsylvania has prepared arapid resource condition assessment protocol that will be applied todetermine the existing quality of Pennsylvania streams to assess im-pacts to those streams and to quantify appropriate compensatorymitigation for impacts to these water resources.

This protocol, advanced by the Bureau of Waterways Engineer-ing andWetlands of the Pennsylvania Department of EnvironmentalProtection, builds on prior work of the U.S. Army Corps of Engi-neers Norfolk District and the Unified Stream Methodology of theVirginia Department of Environmental Quality to provide a consis-tent and rapid condition assessment for projects to obtain water ob-struction and encroachment permits, for water quality certifications,as well as general permits that affect waterways, floodways, and/orfloodplains.

source Environmental Solutions, LLC. He gradu-ated with honors from Northwestern Universityin 2012 with a B.A. degree in environmentalscience and economics. He is a member of theinaugural class of Venture for America.

ACKNOWLEDGEMENTS

We thank the Pennsylvania Department of Envi-

INTRODUCTION

The extensive development of theMarcellus Shale throughout Penn-sylvania has caused a large increase of construction-related impactsto land, waters, wetlands, and streams. Regulatory agencies havelonger permitting backlogs associated with the increased workload

ronmental Protection and Resource EnvironmentalSolutions (RES) for support to document and testthe proposed aquatic resource compensationprotocol. We also thank Bert Laprarie of RES forGeographic Information System analysis.

Copyright ©2013. The American Association of Petroleum Geologists/Division of EnvironmentalGeosciences. All rights reserved.DOI:10.1306/eg.01211312012

Environmental Geosciences, v. 20, no. 2 (June 2013), pp. 53–62 53

and project complexity. A mechanism for quantifyinganthropogenic impacts to wetlands and streams, and acorresponding approach for measuring required com-pensatory mitigation, has recently been introduced inthe Commonwealth of Pennsylvania, which could si-multaneously improve permit timing and increase thereplacement of impacted resources such as wetlandsand streams.

Unavoidable, project-related impacts to wetlandsand streams have increased in the early stages of theMarcellus Shale play life cycle because, at the outset,few or no connections from the wellhead were ob-served to intrastate and interstate pipeline systems.The aerial extent of Marcellus Shale play spans some60,882,397 ac (24,638,253 ha) (U.S. Energy InformationAgency, 2012).More than 16,000,000 ac (6475 ha) havebeen leased for oil and gas development, and thousandsof miles of flowlines, gathering systems, and pipelinesare in process or will be constructed (UnconventionalGas Database, 2012). Both the scale and magnitude of

54 Wetland and Stream Mitigation: Pennsylvania Marcellus Sha

potential impacts from surface operations necessitate amore programmatic approach to the assessment of im-pacts and offsets for streams and wetlands.

If a pipeline runs through wetlands or crossesstreams or rivers, permits are needed from the Penn-sylvania Department of Environmental Protection(DEP). TheMarcellus play area within Pennsylvania en-compasses some 21,223,383 ac (8,588,806 ha), and681,697 wetland acres (275,873 ha) exist within theCommonwealth as measured using the National Wet-land Inventory database (U.S. Department of the Interior,2012). Estimates of waterways, rivers, and streams with-in the entire play area exceed 197,153mi (317,285 km);an estimated 70,180 mi (112,565 km) of streams existwithin Pennsylvania (National Hydrographic Dataset,2012). One pipeline development company has esti-mated that a pipeline must cross a stream every 2000 ft(610 m), meaning that waterways are difficult to avoidand obtaining a permit for a water crossing is commonlyrequired (Figures 1, 2).

Figure 1. Marcellus Wetlands.

le

BACKGROUND

The CleanWater Act of 1972 Section 404 and the Riv-ers and Harbors Act of 1899 Section 10 direct the U.S.Army Corps of Engineers (USACE) to administer aregulatory program for permitting the discharge ofdredged or fill materials in waters of the United Statesincluding navigablewaterways, rivers, streams, their trib-utaries, and associated wetlands. Impacts from dischargeof dredged or fill materials on wetland and stream func-tionsmust be assessed and quantified as part of the per-mit application process.

Assessment methods used to quantify the functionsand values of aquatic resources including wetlands andstreams have evolved for the past 50 yr and, most re-cently, were adapted to consider regional and local con-ditions. The result is the widely used HydrogeomorphicModel (Clairain, 2002). Likewise, resource conditionassessment methods for streams, riparian zones, and

floodplains have been adapted to include local geomor-phology. Additionally, each regulatory agency cate-gorizes water resources in their own manner, neces-sitating a knowledge base of assessment approachesand methods to stay in compliance with play-specificrules and regulations (U.S. Army Corps of Engineersand Galveston District, 2011).

Permit applicants, developers such as oil and gasproducers, pipeline and process plant companies, aswell as governmental entities, commercial firms, andeven residential applicants, use three-step mitigationsequencing to guide their efforts:

Step 1: avoid impacts to regulated and/or other im-portant resources;Step 2: minimize impacts to those resources thatcannot be avoided; andStep 3: mitigate impacts to those resources that can-not be further minimized.

Figure 2. Marcellus Streams.

Goerman et al. 55

At Step 3, the permit applicant calculates theamount of compensatory mitigation required to off-set the unavoidable impacts of the project (Krauss,2009).

On June 9, 2008, the USACE and the Environ-mental Protection Agency made effective the joint Fi-nal Rule governing Compensatory Mitigation forLosses of Aquatic Resources. The Final Rule requiresthat mitigation be identified by the developer beforethe permit is authorized and provides a foundationfor addressing wetland and stream impacts by pointingto mitigation banks as the preferred mitigation solutionin any given watershed (Compensatory Mitigation forLosses of Aquatic Resources, Final Rule, 2008).

Developers who purchase compensatorymitigationcredits from an approved mitigation bank offset envi-ronmental impacts to wetlands or streams. A mitigationcredit is used to offset these environmental losses in theform of wetland credits or stream credits. Mitigationbanks are siteswhere resources such aswetlands, streams,or riparian areas are restored, established, enhanced, orpreserved. The volume of mitigation credits approvedand released by regulatory agencies for use is based onphysical, biological, and chemical factors includingtotal acreage or linear feet of habitat restored, restora-tion type and quality, and overall environmental ben-efits. When mitigation bank credits are used for com-pensatory mitigation, liability for required mitigationtransfers from the developer to the mitigation banksponsor.

PROPOSED APPROACH OF PENNSYLVANIA

On July 1, 2011, the USACE issued the PennsylvaniaSpecial Programmatic General Permit-4 (PASPGP-4).The DEP and county conservation districts can authorizethe use of the PASPGP for minor activities (crossings)in wetlands, streams, rivers, and other waters withoutadditional USACE review. The PASPGP-4 containskey changes that impact linear projects ranging fromnatural gas pipelines to water and sewer pipelines toelectrical transmission, cable television, and telephonelines. Permit applicantsmust supply the locations for thestart and end points, along with each proposed crossing,as well as the total cumulative impacts needed to com-plete the entire project. These are used to determine theactivity category of the impact. For example, if the cu-mulative impact project is greater than 1 ac of jurisdic-

56 Wetland and Stream Mitigation: Pennsylvania Marcellus Sha

tional waters or 250 linear ft of streams, then the entireproject will be a Category III activity and will be re-viewed by the USACE and DEP.

The PASPGP-4 includes clarification on the calcu-lation of the linear footage of stream impact, now tobe measured from the top of the bank to the top ofthe opposite bank and from the upstream to down-stream limits of work. The linear footage of streamimpact will be the greater of these twomeasurements.As such, linear project rights of way will typically bethe basis of the calculations used to determine the lin-ear footage of stream impacts for midstream pipelineprojects. The Department of Environmental Protec-tion permits for water crossings considered PASPGP-4PA Chapter 105 applications a general permit or jointpermit.

During 2011 and 2012, DEP worked to a stan-dardized process for determining aquatic resourcecompensation requirements and simultaneously estab-lish a standardized process for determining the poten-tial value of proposed aquatic resource compensationprojects including mitigation banks. The protocol isintended for use in determining functional compensa-tion requirements for projects affecting waters of theUnited States, which require authorization from theDEP and USACE regulatory programs.

The Pennsylvania Function-Based Aquatic Re-source Compensation Protocol is applied to authorizedactivities permitted via Title 25 PA Code Chapters 105and 106 and ensures compliance with the Final Rule(Pennsylvania Code, 2012). This protocol would re-place the current ratio-based approach of calculatingrequired offsets relative to unavoidable project impacts.

The protocol includes the Pennsylvania RiverineCondition Level 2 Rapid Assessment method, devel-oped to determine the effect of a proposed project onthe basic functions that comprise the riparian ecotoneand to ensure that adequate compensation is providedto offset those effects. The primary modification madeto the popular Unified Stream Methodology reflectsthe approach of DEP to establish the condition of a riv-erine resource using a riparian ecotone. Riparian eco-tones are a three-dimensional space of interaction thatincludes terrestrial and aquatic ecosystems, which ex-tend down into the groundwater, up above the vegeta-tive canopy, out across the floodplain, up the near slopesthat drain water, laterally into the terrestrial ecosystem,and along thewatercourse at a variablewidth. The ripar-ian ecotone includes the 100-yr floodplain and 100 ft(31 m) landward along the valley, where obvious slumps

le

or landslides are added with a 45-ft (14-m) band aroundtheir edge (Verry et al, 2004).

This rapid condition assessment approach was de-veloped to use the components of the riparian ecotoneconcept while balancing the cost of information gath-ering requirements. Ease of data capture, rapid calcula-tion, and comprehensive application by practitioners,commonly biologists, ecologists, geologists, and hy-drologists, were key design elements of the assessmentapproach.

ASSESSING STREAMS AND RIPARIAN AREAS

Permit applicants will propose projects that have un-avoidable impacts to streams of varying type and quality.Therefore, it is important to assess the quality of thestream reach being impacted and to ensure that adequatecompensation is required to offset any unavoidable im-pacts. Those assessing impacts must establish the upperand lower boundaries of the Stream Assessment Reach(SAR) to represent the overall condition of the areawhere the structures or activities may occur. Factors toconsider in determining these boundaries include:

• the upstream influence of backwater projected aspart of the hydrologic and hydraulic analysis and ap-plication of the same distance downstream;

• 20 times the channel width at bankfull stage up-stream and downstream; and

• 250 ft (76 m) upstream and downstream of the pro-posed location of the structure or activity, which-ever is greater.

Once the upper and lower limits of SAR are estab-lished, the assessor establishes the boundaries of the ripar-ian vegetation and the riparian zone of influence (ZOI).Riparian vegetation boundaries can be established by:

• hydrologic modeling analysis to determine 100-yrstorm-event elevations;

• 100-yr Federal Emergency Management Agency(FEMA) floodplain mapping;

• in FEMA unmapped areas, estimating the flood pronearea width by determining the elevation that corre-sponds to twice the maximum depth of the bankfullchannel as taken from the established bankfull stage; or

• 100 ft (31 m) from the stream bank (only used inFEMA unmapped areas) when hydrologic modelinganalysis and stream cross section data are not avail-able for determining the flood-prone area.

Figure 3 shows an example of FEMA floodplainmapping. Whenmapped floodplains are available, theymay be used to establish boundaries for the riparianvegetation and the ZOI. Once the riparian vegetationboundaries are established, the ZOI boundaries are de-termined by extending the riparian vegetation bound-aries 100 ft (31 m) landward on each side along thelength of the riparian vegetation area.

Figure 3. Schematic of streamassessment reach.

Goerman et al. 57

CONDITION INDICES

The individual indices used to establish the overall Ri-parian Ecotone Condition Index (RECI) are:

• Channel/floodplain condition index• Riparian vegetation condition index• Riparian zone of influence condition index• Instream habitat condition index• Channel alteration condition index

58 Wetland and Stream Mitigation: Pennsylvania Marcellus Sha

Each index, and its components and calculationsare described below.

Channel/Floodplain Condition Index

Under most circumstances, stream channels respond todisturbances or changes in flow regime in a sequentialpredictable manner (Rosgen, 1996). The way a streamresponds to changes is by degrading to a lower eleva-tion and eventually restabilizing at that lower elevation

Figure 4. Channel condition index.

Figure 5. Riparian vegetation condition index. SAR = stream assessment reach.

le

(Figure 4). By analyzing the stream channel cross sec-tion at different points along the stream, the differingstages of the stream-channel evolutionary process canbe directly correlated with the current state of streamstability. The condition of a channel can be determinedby visually assessing certain geomorphological indicatorsrelated to the channel geometry, stability, and activefloodplain connection.

Channel GeometryVisually assess the channel profile to determine the de-gree of incision and/or widening. Channel incision is acommon response of alluvial channels that have excessamounts of flow energy or stream power relative to thesediment load. This change in flow regime results in thestream eroding the stream bed, causing steep, easilyeroded banks. If the cohesiveness of the bank materialis very low, such as loose sand, the channel will erodethe banks and have a wide cross section compared to itsdepth. This instability presents itself as an overwidenedchannel.

Channel StabilityAssess visual indicators of stability or instability. In astable stream, the pattern of erosion and deposition oc-curs in an orderly and predictable manner. Indicators ofan unstable stream channel include depositional featuressuch as mid-channel bars, transverse bars, and transientsediments, as well as erosion features such as erosionscars, denuded banks, and threaded channels.

Active Floodplain ConnectionActive floodplain is the land between the active chan-nel at the bankfull elevation and the terraces that areflooded by stream water on a periodic basis. Naturalchannels at or immediately below surrounding flood-plain elevations will be connected to the active flood-plain. Channels that are deeply incised or channelizedwill be below the elevation of the floodplain andwill nolonger be able to likely flood the floodplain during nor-mal high-water events.

The Channel Condition Index is calculated as:

Channel CI ¼ Condition Score20

ð1Þ

Riparian Vegetation Condition Index

This condition index is a qualitative evaluation of thecover types that make up the riparian vegetation within

the 100-yr floodplain limits. This index is determinedby evaluating what cover types occupy what percent-age of the total riparian vegetation area for each side of100-yr floodplain within the SAR. The left side andright side are determined by facing downstream. Aerialphotography combined with a visual observation of theriparian area is used to determine this condition index(Figure 5).

The ideal and/or optimal riparian vegetation wouldbe homogenous with a mature hardwood and/or coniferforest occupying 100% of the assessment area. Any trib-utary stream channels or wetlands located within theriparian vegetation area are scored as optimal. If theriparian vegetation area is heterogeneous (e.g., 33%forested, 33% cropland, and 34% pavement), it is pos-sible that the riparian vegetation area could containmultiple condition categories. In that case, each condi-tion category present within the riparian vegetation areais scored and weighted by the percent it occupies withinthe riparian vegetation area. An estimate of the percentarea that each cover type occupies may be made fromvisual estimates made on the ground or by measuringeach different area to obtain its dimensions.

The following formulas are used in establishing theright and left sides of the riparian vegetation:

Left Side Sub� Index ¼ SUMð%Areas� ScoresÞ20

ð2Þ

Right Side Sub� Index ¼ SUMð%Areas� ScoresÞ20

ð3Þ

Riparian Vegetation CI¼ðLeft Side CIþ Right Side CIÞ2

ð4Þ

Riparian Zone of Influence Condition Index

This index is a qualitative evaluation of the cover typesthat make up the ZOI. The riparian ZOI is the land ex-tending 100 ft (31 m) into the adjacent uplands fromthe 100-yr floodplain limits on both sides of the valleyfloor. The score for this index is determined by evalu-ating which cover type occupies what percent of thetotal ZOI area for each side of the floodplain withinthe SAR. The total ZOI assessment area (on eachside of the 100-yr floodplain limits) is calculated bymultiplying the length of the SAR by 100 ft (31 m).The left side and right side are determined by facing

Goerman et al. 59

downstream. The ideal ZOI would have a homogenousland cover composed of a mature hardwood and/or co-niferous forest occupying 100% of the assessment area.Any tributary stream channels or wetlands locatedwith-in the ZOI areas are scored as optimal. If the ZOI iscomposed of heterogeneous land cover (e.g., 33%forested, 33% cropland, and 34% pavement), it is pos-sible that the ZOI could contain multiple condition cat-egories. In that case, each condition category presentwithin the ZOI is scored and weighted by the percentit occupies within the ZOI.

The following formulas are used if establishingright and left sides of the Riparian ZOI:

Left Side Sub� Index ¼ SUMð%Areas� ScoresÞ20

ð5Þ

Right Side Sub� Index ¼ SUMð%Areas� ScoresÞ20

ð6Þ

Riparian ZOI CI ¼ ðLeft Side CIþ Right Side CIÞ2

ð7Þ

In-Stream Habitat Condition Index

The in-stream habitat assessment considers the habitatsuitability for effective colonization or use by fish, am-phibians, and/or macroinvertebrates. This parameterdoes not consider the abundance or types of organismspresent, nor the water quality of the stream. Other fac-tors beyond those measured in this methodology (i.e.,watershed conditions) also affect the presence and di-versity of aquatic organisms. Therefore, evaluation ofthis parameter seeks to assess the suitability of physicalelements within the SAR to support aquatic organisms.

This parameter includes the relative quantity andvariety of natural structures in the stream, such as cob-ble (riffles), large rocks, fallen trees, logs and branches,persistent leaf packs, and undercut banks, available asrefugia, feeding, or sites for spawning and nursery func-tions of aquatic macro fauna. A wide variety and/orabundance of instream habitat features provide macro-invertebrates and fish with a large number of niches,thus increasing species diversity. As variety and abun-dance of cover decreases, habitat structure becomeshomogenous, diversity decreases, and the potential forrecovery after disturbance decreases. Riffles and runsare critical for maintaining a variety and abundance of

60 Wetland and Stream Mitigation: Pennsylvania Marcellus Sha

benthic organisms and serve as spawning and feeding re-fugia for certain fish. The extent and quality of the riffleis an important factor in the support of a healthy biolog-ical condition. Riffles and runs offer habitat diversitythrough a variety of particle sizes. Snags and submergedlogs are also productive habitat structures for macroin-vertebrate colonization and fish refugia.

Typically, most streams in Pennsylvania are highgradient, with the exception of streams in the coastalplain, low gradient streams flowing through wetlandsor wet meadows, and tributary streams flowing throughlarger floodplains (e.g., tributaries flowing to the Dela-ware and Susquehanna rivers) throughout the state.Headwater stream channels have intermittent hydrolo-gic regimes and may not have the diversity of habitatfeatures found in higher-order stream channels. Hy-porheic flowmay comprise all of the flow in intermittentstreams during dry times of the year. A high-gradientstream should not be scored lower because of the lack ofsubmerged aquatic vegetation. Likewise, a low-gradientstream should not be scored lower because it does notcontain riffles and is sand-dominated substrate.

Channel Alteration Condition Index

This condition index considers direct physical altera-tion to the stream channel from anthropogenic sources.The SAR may or may not have been altered through-out its entire length. Examples of channel alterationsevaluated in this condition index that may disrupt thenatural conditions of the stream include, but are not lim-ited to, the following:

• Straightening of channel or other channelization• Stream crossings (bridges and culverts)• Riprap along stream bank or in stream bed• Concrete, gabions, or concrete blocks along stream

bank• Manmade embankments on stream banks, including

spoil piles• Constrictions to stream channel or immediate flood-

prone area

This condition index evaluates the physical channelalteration, separate from any impact the alteration is hav-ing on the assessment reach. Any impact to the assess-ment reach resulting from the alteration (i.e., scouring,head cuts, vertical banks, etc.) is accounted for in thechannel/floodplain condition index. Any revegetationor natural restabilization of the channel is also accounted

le

for in that condition index. For example, consider twoassessment reaches, each with similar bridges: the firstreach shows no adverse effects to the stream channelor banks, whereas the second shows significant scouring.The alteration is the bridge, not the effects of the bridge;therefore, it is the length of the bridge relative to thelength of the assessment reach that is evaluated. Thescour effect of the bridge would be considered underthe channel/floodplain condition and in the scoring ofthat condition index. The presence of a structure doesnot necessarily result in a reduced score. For instance,a bridge that completely spans the floodplain wouldnot be considered an alteration. Also, the assessor is cau-tioned not tomake assumptions about past alterations. In-cision can commonly bemistaken for past channelization.

Riparian Ecotone Condition Index

The RECI is a numerical value placed on the SAR usingthe scores determined from each individual condition in-dex during the stream assessment. Each individual condi-tion index score should result in a value from 0.05 to 1.0.The RECI score should also result in a score from 0.05 to1.0. If values greater than 1.0 result, then it is likely thatthe individual scores are being used andnot the calculatedindexes. The individual condition indexes are equallyweighted, and the RECI is calculated by summing the in-dividual condition indexes and then dividing by 5. Thefollowing equation is used to determine the RECI:

RECI ¼ ðSum of Condition Index ScoresÞ5

ð8Þ

COMPENSATORY MITIGATIONCREDIT DETERMINATION

The indices and scores determined by the applicationof the Pennsylvania Riverine Condition Level 2 RapidAssessmentmethod are applied to theCompensationRe-quirement Equation to determine the number of creditsrequired to offset the measured impact. The RECI pa-rameter is one of the four parameters used in this equa-tion with the other three being the area of impact, theproject effect factor—a score of the relative impact onbiogeochemical, habitat, and hydrologic groups—andthe resource value—a Pennsylvania Chapter 93 designa-tion noting the category of the stream being affectedusing designations made in state statutes. The resulting

credits required as a compensation requirement are cal-culated as:

Credits Required ¼ Area of Impact� Project Effect Factor� Resource Value Factor� RECI

ð9Þ

For the assessor/practitioner, therefore, the river-ine compensation requirement is a matter of answeringfour questions:

1. What is the area of impact? This is measured as thearea of stream and/or floodplain impacted. For pre-impact permits, this is commonly the area of thestream open cut for pass through. If stream crossingsvia horizontal directional drilling are used to mini-mize impacts, the area of impact may be locatedat the entry and exit points of the bore. For after-the-fact permits, include any horizontal directionaldrilling frac-out impacts and unplanned temporaryworkspaces as impact areas.

2. What is the nature of the impact? This is a relativerating from none to severe.

3. What is the Chapter 93 Stream Designation? Thedesignations by Pennsylvania via Title 25 PA CodeChapter 93 are exceptional value, high quality,trout stocked fishery, cold water fishery, migratoryfishery and warm water fishery.

4. What is the RECI? The condition index score thatresults from the assessment of chemical, physicaland biological attributes that contribute to maintain-ing downstream water quality designations and uses.

The developer would then seek to source the result-ing number of compensatory mitigation credits from anapproved mitigation bank to satisfy the mitigation re-quirement of the permit application. The permittingauthority is assured that the mitigation offset debitedfrom the mitigation bank are ecologically sound inthe actual wetland and/or stream restoration has oc-curred, thus maintaining the no net loss of wetlandand stream policy, established in the United States in1977 (Executive Order 11990, 1977).

CONCLUSIONS AND RECOMMENDATIONS

In terms of impacts and offsets to thewaters of theUnitedStates, the authors are aware of dozens of assessment

Goerman et al. 61

methods applied by regulatory agencies to permit projectsin each unconventional play (Krauss, 2013). These proj-ects include drilling pad sites, access roads, flowlines,gathering systems, trunks, laterals and pipelines to trans-port captured hydrocarbons from wellhead to marketand between interstate markets. Pennsylvania, mostlyas a response to impacts from Marcellus Shale gas dril-ling and associated field infrastructure development, hasapplied a riparian ecotone approach to create a new rap-id assessment method that ensures the long-term via-bility of riverine aquatic resources and quantifies bothunavoidable impacts and required compensatory offsetmitigation. This approach is a framework for resourceplanning and is a quantitative approach that builds onmitigation sequencing. The Level 2 riverine assessmentmethod provides a standardized measurement and re-placement mechanism for resource impacts. The com-pensation protocol readily assesses ecosystem servicesin terms of their biogeochemical, hydrologic, habitat,and resource support functions. This method will be ap-plied to diverse water resources across Pennsylvania,used as a tool for permittees to plan, avoid andminimizeimpacts, and used by agencies as part of a streamlinedregulatory review process. The new approach recognizesthe aquatic resource functions and values impacted frompermittee projects, provides a standardmethod of quanti-fying ecologically appropriate compensatory mitigation,andultimately enables all practitioners to do their jobs eas-ier, faster, and in an environmentally responsible manner.

REFERENCES CITED

Clairain, E. J. Jr., 2002, “Hydrogeomorphic approach to assessingwetland functions: Guidelines for developing regional guide-books: Chapter 1. Introduction and overview of the hydro-

62 Wetland and Stream Mitigation: Pennsylvania Marcellus Sha

geomorphic approach: ARDC/EL TR-02-3, Vicksburg,Mississippi, U.S. Army Engineer Research and DevelopmentCenter, 39 p.

CompensatoryMitigation for Losses of Aquatic Resources, Final Rule,2008, Federal Register, 33 CPR Parts 325 and 332 and 40 CFRPart 230, April 20, 2008, p. 19,594–19,705.

Executive Order 11990, 1977, 42 FR 26961, 3 CFR, Comp., May 24,1977, p. 121.

Krauss, R. F., 2009, An integrated approach to wetland miti-gation, Pipeline and Gas Journal, September 2009, v. 235,no. 9, 4 p.

Krauss, R. F., 2013, Addressing well and field infrastructure sitingchallenges in the wetlands and streams of the Haynesville,Marcellus, Utica and Eagle Ford Shale plays: Society of Petro-leum Engineers Annual Technical Conference, SPE Paper163804, Galveston, Texas, March 19, 2013, 8 p.

National Hydrographic Dataset, 2012, Coordinated effort betweentheUnited States Department of Agriculture–Natural ResourcesConservation Service (USDA-NRCS), the United States Geo-logical Survey (USGS), and the Environmental Protection Agency(EPA): accessed October 1, 2012, http://datagateway.nrcs.usda.gov.

Pennsylvania Code, 2012, Title 25: accessed October 1, 2012,http://pacode.com/secure/data/025/chapter105/chap105toc.html.

Rosgen, D., 1996, Applied river morphology, 2d ed.: ColoradoSprings, Colorado, Wildland Hydrology, 390 p.

Unconventional Gas Database, 2012, Houston, Texas, Hart EnergyPublications.

U.S. Army Corps of Engineers, Galveston District, 2011, InterimSWG stream condition assessment standard operating proce-dures: Galveston, District, Texas, USACE Galveston District,31 p.

U.S. Army Corps of Engineers, 2007, Norfolk District and Vir-ginia Department of Environmental Quality Unified StreamMethodology: Norfolk, Virginia, U.S. Army Corps of Engineersand Norfolk District, 37 p.

U.S. Department of the Interior, 2012, Fish and Wildlife ServiceNational Wetlands Inventory: accessed October 1, 2012,http://www.fws.gov/wetlands.

U.S. Energy Information Agency, 2012, accessed March 15, 2012,http://www.eia.gov/pub/oil_gas/natural_gas/analysis_publications/maps/maps.htm.

Verry, E. S., et al., 2004, Riparian ecotone: A functional definitionand delineation for resource assessment—Water, Air, & Soil Pol-lution: Focus, v. 4, no. 1, p. 67–94.

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