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Evaluating expected outcomes of acid remediation in an intensively mined Appalachian watershed Andrew S. Watson & George T. Merovich Jr & J. Todd Petty & J. Brady Gutta Received: 15 November 2016 /Accepted: 30 May 2017 # Springer International Publishing Switzerland 2017 Abstract Assessments of watershed-based restoration ef- forts are rare but are essential for the science of stream restoration to advance. We conducted a watershed scale assessment of Abram Creek before and after implementa- tion of a watershed-based plan designed to maximize ecological recovery from acid mine drainage (AMD) im- pairment. We surveyed water chemistry, physical habitat, benthic macroinvertebrates, and fish community structure in three stream types: AMD-impacted (14 streams), AMD- treated (13 streams), and unimpaired reference (4 streams). We used in-stream measurements to quantify ecological loss from AMD, the amount of ecological recovery ex- pected through remediation, and the observed degree of post-treatment recovery. Sites impaired by AMD im- proved in water quality with AMD treatment. Dissolved metals and acidity declined significantly in treated streams, but sulfate and specific conductance did not. Likewise, sites impaired by AMD improved in bio-condition scores with AMD treatment. EPT genera increased significantly but were lower compared to unimpaired streams. We found fish at nine treated sites that had none before treatment. Community-level analyses indicated improved but altered assemblages with AMD treatment. Analysis of pre- treatment conditions indicated that only 30% of the historic fishery remained. Remediation was expected to recover 66% of the historic fishery value, and assessment of post- treatment conditions indicates that 52% of the historic fishery has been recovered after 3 years. Developing ex- pected endpoints for restoration outcomes provides a tool to objectively evaluate successes and can guide adaptive management strategies. Keywords Acid mine drainage . Acid remediation . Adaptive watershed management . Ecological units . Watershed scale remediation . Predictive models Introduction Stream restoration is increasingly used to alleviate negative impacts associated with anthropogenic landscape change. In the USA alone, an average of $1 billion dollars per year is invested in this effort (Bernhardt et al. 2005). Surprisingly, howev- er, there are no agreed upon standards for what constitutes success given this large investment (Palmer et al. 2005) and assessment of such pro- jects are rare (Bernhardt et al. 2005; Heinrich et al. 2014 ). In central Appalachia, a considerable amount of research and development targets reme- diation of acid-impacted watersheds (Freund and Petty 2007; Merovich et al. 2007; Petty et al. 2008). In this region, coal has been mined for Environ Monit Assess (2017) 189:339 DOI 10.1007/s10661-017-6036-x A. S. Watson (*) : J. T. Petty School of Natural Resources, West Virginia University, Morgantown, WV 26506, USA e-mail: [email protected] G. T. Merovich Jr, Department of Environmental Science and Studies, Juniata College, Huntingdon, PA 16652, USA J. B. Gutta Antero Resources, 535 White Oaks Blvd, Bridgeport, WV 26330, USA

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Evaluating expected outcomes of acid remediation in anintensively mined Appalachian watershed

Andrew S. Watson & George T. Merovich Jr &

J. Todd Petty & J. Brady Gutta

Received: 15 November 2016 /Accepted: 30 May 2017# Springer International Publishing Switzerland 2017

Abstract Assessmentsofwatershed-basedrestorationef-forts are rare but are essential for the science of streamrestoration to advance. We conducted a watershed scaleassessment of AbramCreek before and after implementa-tion of a watershed-based plan designed to maximizeecological recovery from acid mine drainage (AMD) im-pairment. We surveyed water chemistry, physical habitat,benthic macroinvertebrates, and fish community structurein threestreamtypes:AMD-impacted(14streams),AMD-treated (13streams), andunimpaired reference (4 streams).We used in-stream measurements to quantify ecologicalloss from AMD, the amount of ecological recovery ex-pected through remediation, and the observed degree ofpost-treatment recovery. Sites impaired by AMD im-proved in water quality with AMD treatment. Dissolvedmetalsandaciditydeclinedsignificantly in treatedstreams,but sulfate and specific conductance did not. Likewise,sites impaired by AMD improved in bio-condition scoreswith AMD treatment. EPT genera increased significantlybutwerelowercomparedtounimpairedstreams.Wefoundfish at nine treated sites that had none before treatment.

Community-level analyses indicated improved but alteredassemblages with AMD treatment. Analysis of pre-treatmentconditions indicated thatonly30%of thehistoricfishery remained. Remediation was expected to recover66% of the historic fishery value, and assessment of post-treatment conditions indicates that 52% of the historicfishery has been recovered after 3 years. Developing ex-pected endpoints for restoration outcomes provides a toolto objectively evaluate successes and can guide adaptivemanagement strategies.

Keywords Acidmine drainage . Acid remediation .

Adaptive watershedmanagement . Ecological units .

Watershed scale remediation . Predictivemodels

Introduction

Stream restoration is increasingly used to alleviatenegative impacts associated with anthropogeniclandscape change. In the USA alone, an averageof $1 billion dollars per year is invested in thiseffort (Bernhardt et al. 2005). Surprisingly, howev-er, there are no agreed upon standards for whatconstitutes success given this large investment(Palmer et al. 2005) and assessment of such pro-jects are rare (Bernhardt et al. 2005; Heinrich et al.2014). In central Appalachia, a considerableamount of research and development targets reme-diation of acid-impacted watersheds (Freund andPetty 2007; Merovich et al. 2007; Petty et al.2008). In this region, coal has been mined for

Environ Monit Assess (2017) 189:339 DOI 10.1007/s10661-017-6036-x

A. S. Watson (*) : J. T. PettySchool of Natural Resources, West Virginia University,Morgantown, WV 26506, USAe-mail: [email protected]

G. T. Merovich Jr,Department of Environmental Science and Studies, JuniataCollege, Huntingdon, PA 16652, USA

J. B. GuttaAntero Resources, 535 White Oaks Blvd, Bridgeport, WV 26330,USA

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nearly 200 years (Merovich et al. 2007), and as aconsequence, over 17,000 km of streams in theMid-Atlantic Highlands are impacted by acid minedrainage (AMD) (USEPA 2000). In fact, the legacyeffects of coal mining on aquatic ecosystems repre-sent a crucial environmental issue in this region(Petty et al. 2010).

Historically, most restoration projects were smallscale (Bernhardt et al. 2005) and focused on improv-ing local (stream segment-level) environmental con-ditions. Localized projects commonly fall victim tothe Bfield of dreams^ myth (Hilderbrand et al.2005). This myth, of ecological restoration, is basedon the assumption that if the habitat is restored, thefunction of the ecosystem will self-assemble alongwith the recolonization of biotic communities(Hilderbrand et al. 2005). This assumption that Bifyou build it they will come^ ignores processes oc-curring in the broader, watershed scale context(Merovich et al. 2013). In fact, metacommunitytheory suggests that Bif you build it, they may notcome^ (Brown et al. 2011). Consequently, remedia-tion programs must focus on recovering connectivityamong stream reaches within the entire drainagenetwork (Jansson et al. 2007; Lake et al. 2007;McClurg et al. 2007). This approach requires ad-dressing a strategic proportion of identified problemsources at the watershed scale (Petty et al. 2008).

The purpose of this paper is to present a case where astrategic watershed-based remediation initiative was im-plemented around AMD treatment to maximize water-shed scale recovery. We ask: what is the expected ben-efit of the initiative and how does it compare to observedoutcomes? We studied Abram Creek, a sub-watershedof the North Branch of the Potomac River basin in theeastern panhandle of West Virginia (WV). We answeredthe question with a unique analysis of data collectedaround a watershed-based experimental survey de-signed specifically to (1) quantify the response of waterchemistry, benthic macroinvertebrates, and fish to AMDtreatment 3 years after remediation efforts were imple-mented and (2) evaluate the predicted outcomes ofremediation for different aquatic life end points. Thiseffort to address the expected outcomes of acid remedi-ation on aquatic life at the watershed scale is the first weknow of, and it could provide critical information need-ed in adaptive management framework for managingheavily impacted watersheds (Petty et al. 2010;Merovich et al. 2013).

Methods

Study area

Abram Creek is a 115-km2 watershed (North Branch/Potomac River basin) located in the eastern panhandleof WV in Grant and Mineral Counties (latitude 39° 18′44.8″, longitude 79° 12′ 41.2″). The Abram Creekmainstem is 31.5 km and flows north from an elevationof 1065 m in the headwaters to 516 m at its confluencewith the North Branch of the Potomac River upstream ofKitzmiller, Maryland (Fig. 1). Land cover is dominatedby forest (66%) and agriculture (25%); geology consistspredominantly of shale and sandstone. The watershedcontains 23 mapped stream segments; the largest ofwhich are Emory Creek, Glade Run, Johnnycake Run,and Laurel Run (Fig. 1). Impairments throughout thewatershed are primarily due to AMD from abandonedmine lands (AMLs; West Virginia Water Research In-stitute (WVWRI) 2007). West Virginia Department ofEnvironmental Protection (WVDEP), Division ofWaterand Waste Management identified 27 abandoned minesources (discharges, seeps, portals, culverts, refuse piles,diversion ditches, and ponds) throughout the study area(WVWRI 2007). There are eight National PollutionDischarge Elimination System (NPDES) permits in thewatershed for metal effluents related to mining(WVWRI 2007).

In 2007, the WVWRI proposed a strategicwatershed-based remediation plan, following adaptivewatershed management principles, for the Abram Creekwatershed to the WVDEP Office of Abandoned MineLand and Reclamation. In 2010, the project was com-pleted. The AMD treatment technology implemented inthe watershed includes three liming dosers at the AbramCreek headwaters: AbramCreek right fork, Little Creek,and an unnamed tributary at river kilometer 6.2; twolimestone sand dump sites at Laurel Run and EmoryCreek; and one passive treatment system at Glade Run(Fig. 1 and Table 1). Dosers were installed adjacent toimpacted tributaries. This treatment technology divertswater to a water wheel that drives an auger addingcalcium oxide in proportion needed to neutralize in-stream acidity. Treated water returns to the streamwhereprecipitation reactions occur. Limestone sand applica-tion is performed by dumping sand along the streambank where gravity and streamwater gradually wash thesand downstream, thereby neutralizing acidity(McClurg et al. 2007). The passive treatment system

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installed incorporated kiln dust, a waste product of thelimestone industry, into the stream bed and bank. Acidicwater from abandoned mine portals passes over thismaterial and is neutralized.

Site selection

We studied 18 sites within the study area (Table 1). Siteswere strategically selected based on treatment locationsto evaluate the putative benefits of treatment (Fig. 1). In2008, 13 AMD sites and 1 reference site were sampledto quantify pre-treatment conditions. These same 14sites were sampled again in 2013 to quantify post-treatment conditions, along with 4 additional sites toincrease the number of unimpaired reference and un-treated AMD streams (Table 1).

Streams were classified into three a priori types: (1)streams impaired by AMD (14 streams), (2) streams

treated for AMD impairment (13 streams), and (3) un-impaired reference streams (4 streams) (Table 1). AMD(A) streams were listed on the 2004 303d list for waterquality and/or biological impairment (WVWRI 2007).Treated (T) streams received AMD treatment or weredownstream of treatment. Reference (R) streams werenaturally circumneutral. Circumneutral streams withinthe study area represent the best available conditions inthe watershed and provide the only reasonable referencecondition against which to assess watershed-based re-mediation plans (Campbell 2000, McClurg et al. 2007).

Data collection

We monitored water chemistry in May of 2008 and2013 at each assessment site by collecting a 1-L unfil-tered grab sample and 500-mL filtered sample (0.45-μmpore, mixed cellulose ester membrane discs) (see

Fig. 1 Map of Abram Creekwatershed in West Virginia’seastern panhandle (inset) alongwith AMD treatment locationsand sample sites

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Merovich and Petty 2007). Samples were analyzed atthe National Research Center for Coal and Energy atWest Virginia University for alkalinity (mg/L CaCO3

equivalents), acidity (mg/L CaCO3 equivalents), SO42−

(mg/L), and dissolved Al, Ba, Cu, Cl−, Co, Cr, Cd, Ca,Na, Ni, Se, Zn, Fe, Mg, and Mn concentrations (mg/L).We also measured temperature (°C), pH, specific con-ductance (μS/cm), dissolved O2 (mg/L), and total dis-solved solids (g/L) in situ using a YSI 650 with a 600XL sonde (Yellow Springs Instruments, Yellow Springs,OH). In addition, we evaluated physical habitat condi-tion with rapid visual habitat assessment (RVHA) tech-niques for each site in the late summer of 2008 and 2013following US Environmental Protection Agency(USEPA) protocols (Barbour et al. 1999).

We monitored biological condition at each site bycollecting benthic macroinvertebrate and fish assemblagedata.Benthicmacroinvertebratesweresampledateachsitein May of 2008 and 2013 following rapid bioassessmentprotocols for wadeable rivers (Barbour et al. 1999). Weobtained four kick samples at each site using a rectangularkick-net (net dimensions 355 × 508 mm with 500 μmnetting) from widely separated riffle habitat to sample atotal of 1.0 m2. We filtered all four samples through a250-μmsieve and combined them into a single composite

sample.Thecompositesamplewasimmediatelypreservedin 95%ethanol. Subsampling followed amodified versionof theUSEPA’sRapidBioassessment Protocol.We select-ed a sub-sample of 200 macroinvertebrates by pickingindividuals from randomly selected grid cells (WVDEP2013).We identified allmacroinvertebrates to genusor thelowest possible taxonomic level using Peckarsky et al.(1990)andMerritt andCummins (2008).Wecollected fishassemblagedata in the latesummerof2008and2013usingone to three backpack electrofishing units (Smith Rootmodels 12-B, 15-D, and/or LR-24) depending on the sizeof the stream (FreundandPetty 2007).Reach lengthswere40 times themean streamwidthwith aminimumof 150mand a maximum of 300 m (Freund and Petty 2007). Weused single passes, which have been found to be sufficientat thesedistances for estimating relative species richnessorcomparing relative biological conditions (Freund andPetty 2007). All individual fish captured were identifiedto species, counted, and returned to the stream alive.

Statistical analyses

Our first objective was to quantify the response of waterchemistry, benthic macroinvertebrates, and fish to AMDtreatment 3 years post-treatment. To meet this objective,

Table 1 Site names, GPS coordinates of sampling locations, stream type, and treatment technology implemented

Site name Latitude Longitude Stream type 2008 Stream type 2013 Treatment type

Abram Creek at mouth 39.37938 −79.20199 AMD (A1) Treated (T1) Downstream

Abram Creek above Emory Creek 39.35369 −79.17154 AMD (A3) Treated (T3) Downstream

Emory Creek at mouth 39.35429 −79.16722 AMD (A2) Treated (T2) LS sand

Unnamed tributary 2 of Emory Creek 39.33565 −79.15524 NS Reference (R2) –

Emory Creek headwater right fork 39.33565 −79.15599 NS Reference (R3) –

Emory Creek headwater left fork 39.33565 −79.15524 NS AMD (A14) –

Abram Creek at Laytons 39.35058 −79.18403 AMD (A4) Treated (T4) Downstream

Johnnycake Run at mouth 39.31358 −79.21424 Reference (R) Reference (R) –

Upper Johnnycake Run 39.30171 −79.21109 NS Reference (R4) −Abram Creek above Johnnycake Run 39.31370 −79.21385 AMD (A5) Treated (T5) Downstream

Glade Run at mouth 39.30629 −79.18667 AMD (A6) Treated (T6) Passive

Abram Creek above Glade Run 39.30453 −79.18884 AMD (A7) Treated (T7) Downstream

Laurel Run at mouth 39.29607 −79.19072 AMD (A8) Treated (T8) LS sand

Abram Creek above Laurel Run 39.29654 −79.19087 AMD (A9) Treated (T9) Downstream

Abram Creek at Vindex 39.23752 −79.21071 AMD (A10) Treated (T10) Downstream

Abram Creek at CR 42 39.23161 −79.21660 AMD (A11) Treated (T11) Downstream

Little Creek 39.21851 −79.21824 AMD (A12) Treated (T12) Doser

Abram Creek headwaters 39.21855 −79.22520 AMD (A13) Treated (T13) Doser

NS not sampled, Downstream site is downstream of treatment, LS sand limestone sand, − no treatment, Doser Lime doser

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we used a combination of multivariate statistics andordination procedures. Prior to analyses, all water chem-istry variables except pH were log transformed to ap-proximate assumptions of parametric statistics. Alkalin-ity was normalized after adding 1 mg/L CaCO3 equiv-alents to its value, and total acidity was removed fromthe analysis due to its strong dependence on other chem-ical elements (Merovich et al. 2007). Cd was not includ-ed in the analysis because all concentrations returned bythe lab were below the detection limit. First, we usedprincipal component analysis (PCA) to analyze the wa-ter chemistry data pre- and post-treatment. Principalcomponents (PCs) with eigenvalues >1.0 were consid-ered significant (McGarigal et al. 2000). Water chemis-try parameters were considered strongly correlated to aPC if their factor loadings had an absolute value >0.5(McGarigal et al. 2000). Separation of water samples(e.g., AMD-type) in ordination space was used to inter-pret the degree of difference in water quality (i.e., chem-ical make-up) relative to other sample types (e.g., treat-ed-type). We used multivariate analysis of variance(MANOVA) to determine if a priori stream types hadstatistically different water chemistry signatures. Anal-ysis of variance (ANOVA) and Tukey’s HSD post-testswere used to determine which specific water chemistryparameters were statistically different among streamtypes.

To further examine the chemical response to treat-ment, we calculated acid loads and the net acidity at themouth of the watershed and major tributaries pre- andpost-treatment. Acid and alkalinity loads were calculat-ed by multiplying flow in volume per minute by acidityor alkalinity concentration in CaCO3 equivalents, re-spectively. Final values were converted to tons/year.Flows for each of the major tributaries receiving AMDtreatment were calculated by using the flow with drain-age area ratio method (Emerson et al. 2005). To calcu-late drainage area, we used a hydrologic model inArcMap Version 10.1 (Environmental Systems Re-search Institute, Redlands, CA, USA) to find the totalflow accumulation values for each major tributary re-ceiving AMD treatment. Net acidity was calculated bysubtracting alkalinity from calculated acidity. Addition-ally, we used MANOVA to determine if RVHA param-eters differed between a priori stream types.

To investigate the response of fish and macroinver-tebrate communities to watershed-based remediation,we used nonmetric multidimensional scaling (NMDS;Bray-Curtis distance coefficient). To interpret the

gradient structure in the NMDS solutions at acceptablestress levels, we labeled samples (sites) in ordinationspace with a priori stream types and added to the ordi-nation the weighted mean positions of selected taxa. Wealso correlated biological metrics and water chemistryparameters to the ordinations. Correlations were consid-ered statistically significant when p < 0.05 (for 999permutations of the data). To statistically test whetherdifferences existed among communities from differentstream types as suggested by NMDS ordinations, weused analysis of variance using distancematrices (ADO-NIS; i.e., nonparametric multivariate analysis of vari-ance), with statistical significance (p < 0.05) evaluatedwith 999 permutations. In addition, the West VirginiaStream Condition Index (WVSCI), a benthic macroin-vertebrate family-level index of biotic integrity (IBI),and the Genus Level Index of Most Probable StreamStatus (GLIMPSS), a genus-level benthic macroinverte-brate IBI, were used to quantify ecological integrity ateach sample site (Gerritsen et al. 2000; Pond et al.2008). We calculated five benthic macroinvertebratecommunity metrics. These included Ephemeroptera,Plecoptera, Trichoptera (EPT) genus richness, genusrichness, % EPT families, % Chironomidae, and % 2dominant for each site (see Pond et al. 2008). For fish,we calculated seven community metrics. These includedspecies richness, number of benthic species, sensitivespecies richness, proportion of tolerant individuals, pro-portion of invertivore-piscivore individuals, proportionof macro-omnivores, and proportion of gravel spawningspecies for each site (see McCormick et al. 2001).ANOVA and Tukey’s HSD post-tests were used todetermine which specific benthic macroinvertebrateand fish metrics were statistically different amongstream types. Paired t tests were used to compare mac-roinvertebrate IBIs’ pre- and post-treatment. All statis-tical analyses were conducted in the R statistical envi-ronment Version 3.0.2 (R Development Core Team2013). NMDS and ADONIS were performed with thepackage vegan (Oksanen et al. 2013).

To address our second objective, we calculated ecolog-ical units (EUs; sensu Petty and Thorne 2005; Merovichand Petty 2007) to quantify ecological function of streamsegments in the AbramCreek watershed. EUs are units ofstreamlength (km)weightedbyanecological function thatreflects thequalityof thestreamsegment(PettyandThorne2005). For example, a stream segment with a length of2.5kmandaweightingvalueof0.70wouldpossess anEUvalue of 1.75 km. The highest quality stream segments

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receive weighting values of 1.0, implying that these seg-ments are functioning at 100% of that expected for streamsegments in that region.EUs therefore representecologicalvalue in units of river length and can be viewed as theavailability of ecologically functioning stream habitat(Petty and Thorne 2005).

Using this concept, we developed a way to firstestimate conditions before impairment, which wetermed Historic EUs (HEUs). HEUs were calculated asstream segment length (SL) × ecological potential (EP;see below). We then quantified lost EUs (LEUs;HEUs − Pre-EUs) relative to current conditions beforetreatment (Pre-treatment EUs; Pre-EUs). Pre-EUs werecalculated as SL × EP × ecological condition beforetreatment (EC; see below). LEUs were used to estimaterecoverable EUs (REUs) as a result of remediationefforts. REUs were calculated as LEUs × ecologicalremediablity (ER; see below). To predict future EUs(FEUs), we then added back REUs to Pre-EUs (Pre-EUs + REUs). Next, we calculated EUs 3 years aftertreatment (Post-treatment EUs; Post-EUs) in the sameway as Pre-EUs but with EC values after treatment.Finally, we compared Post-EUs to FEUs for each sam-pling location. Table 2 details how these units werecalculated using three terms that varied by weightingfunctions: EP, EC, and ER (Fig. 2). Further, we devel-oped these pre- and post-treatment EUs as well as theexpected REUs and FEUs (Table 2) for four differentaquatic life endpoints as discussed below: brook troutfishery EUs, stocked trout fishery EUs, macroinverte-brate diversity EUs, and overall fishery EUs, whichcombined elements of brook trout and stock trout fish-ery EUs (sensu Petty et al. 2008).

First, the EP function explains the prospective valueof a stream reach as ecological habitat given successfulremediation and is based on drainage area (DA). Forexample, the ecological potential function for the brooktrout fishery EU is set to 1.0 for DA 0–40 km2, thendeclines linearly for DA >40 km2 (Fig. 2a), becausenative brook trout ecology is concentrated within smalldrainage areas (Petty and Thorne 2005). Conversely, theecological potential function for the stocked trout fish-ery EU is set to 0.0 for DA 0–20 km2, then increaseslinearly for DA >20 km2 (Fig. 2a), because stocked troutfisheries are typical of larger drainages where recrea-tional use potential is high (Heidinger 1999). The eco-logical potential function for the macroinvertebrate di-versity EU, which is based on WVSCI (see below), isset to 1.0 for all drainage areas because streams of all

sizes should be functioning at full potential in terms ofthis invertebrate IBI (Fig. 2a).

On the other hand, the EC function explains the currentvalueofthestreamreachashabitat forbiologicaldiversityoras a fishery and is predicted based on WVSCI scores.WVSCI ranges from 0 to 100 with higher scores reflectingbetter stream ecosystem condition (Gerritsen et al. 2000).For example, the EC function for the macroinvertebratediversity EU is 0.0 for WVSCI 0–40, because conditionsare very poor in that range (Gerritsen et al. 2000). Thefunction then increases linearly to 1.0 for WVSCI 40–80as conditions improve (Fig. 2b). The function does notincrease to 1.0 for the brook trout fishery EU untilWVSCIreaches 80.0 (Fig. 2b), because brook trout are more sensi-tivetooverallecologicalcondition(PettyandThorne2005).Thefunctionincreasesto1.0for thestockedtroutfisheryEUwhenWVSCI reaches 60.0 (Fig. 2b), because stocked troutare generally more tolerant of sub-optimal conditions of aput-and-take fishery (Trushenski et al. 2010).

Finally, the ER function relates the likelihood ofremediation to drainage area and treatment type. In thisstudy, at-source treatment refers to passive AMD reme-diation systems near the source of AMD, while in-stream approaches refer to liming dosers and limestone

Table 2 Ecological unit (EU; ecologically functioning streamkilometers) calculations used to estimate conditions before impair-ment to quantify lost EUs and then predict the amount of EUsrecoverable after treatment for each segment-level watershed inthe study area

Ecological units (EUs) Equations

Historic EUs (HEUs) SL × EP

Pre-treatment EUs(Pre-EUs)

SL × EP × EC before AMDtreatment

Lost EUs (LEUs) HEU − Pre-EU

Recoverable EUs (REUs) LEU × ER

Future EUs (FEUs) Pre-EU + REU

Post-treatment EUs(Post-EUs)

SL × EP × EC after AMDtreatment

Historic EUs estimate conditions before impairment. Pre-treatment EUs represent the actual conditions before remediation.Lost EUs represent the amount of ecologically functioning streamhabitat lost as a result of AMD impairment. Recoverable EUsrepresent the amount of ecologically functioning habitat that canbe recovered as a result of acid remediation. Future EUs estimatethe predicted response to treatment, and post-treatment EUs esti-mate the actual conditions after remediation. EP, EC, and ERdepend on the different weighting functions in Fig. 2. Each EUwas calculated for each of the four aquatic life endpoints

SL stream segment length, EP ecological potential, EC ecologicalcondition, ER ecological remediability

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sand dumpsites further away from AMD sources. Forexample, the ER weighting function increases linearlyto 1.0 as DA increases to 20 km2 for at-source treatment,whereas for in-stream treatment, DA must reach 10 km2

before remediability begins to accrue weight (Fig. 2c).

Remediation of small streams (less than 2 km2) is un-likely for both at-source and in-stream treatment ap-proaches because the proximity to chemical treatmentcreates a chemical mixing zone that prevents biologicalrecovery (McClurg et al. 2007). Furthermore,

0 50 100 150

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rot

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Fig. 2 Weighting functions for aecological potential (EP), becological condition (EC), and cecological remediability (ER)used to calculatemacroinvertebrate diversity,brook trout fishery, and stockedtrout fishery EUs for eachsegment in the Abram Creekwatershed. Diversity EU (a, b) =macroinvertebrate diversity EU

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remediation is expected to be less likely using in-streamapproaches as compared to at-source approaches, espe-cially in small- to moderate-size streams (Petty et al.2008). Therefore, low remediability is associated withsmall drainage area within close proximity to treatment.Remediability increases as stream size and distance totreatment increases (McClurg et al. 2007).

To spatially analyze pre- and post-treatment ecolog-ical conditions, we assigned each of our observed pre-and post-treatment WVSCI scores to their appropriatesegment-level watershed (Merovich and Petty 2007;Strager et al. 2009). Next, we linearly interpolatedWVSCI scores between segment-level watershedsbounded by observed scores (Merovich and Petty2007). This was necessary to assign WVSCI scores toun-sampled segment-level watersheds throughout thestream continuum. Finally, we accumulated thesegment-level watershed values for each EU type fromthe headwaters to the mouth to obtain an ecologicalcurrency in stream kilometers at the watershed scale.We ran two-sample Kolmogorov-Smirnov tests to de-termine if statistical differences existed between thecumulative distribution curves of observed post-treatment EUs versus expected (i.e., future) post-treatment EUs for each EU type in the watershed.

Results

Physicochemical

Weobservedhighvariability inwater chemistry throughoutthewatershed. PCA revealed four important dimensions ofvariation (eigenvalues >1.0). Only PC 1 and PC 2 wereinterpreted, because theywere statistically different amongstreamtypes (Table3).Combined,PC1andPC2explained69% of the variance observed in water chemistry. PC 1 isinterpreted as a pollution gradient explaining 46% of thevariance. PC1was strongly correlatedwithAl,Ba,Cu,Co,Cr, Ni, Zn, SO4

2−, Fe, Mg, and Mn concentrations in thepositive direction (Fig. 3). Alkalinity and pHwere correlat-ed negatively with PC 1 (Fig. 3). PC 2 is interpreted as ahardness gradient explaining 23% of the variance in waterchemistry data. PC 2 was strongly correlated with specificconductance, Ca, Mg, Na, and SO4

2− in the positive direc-tion(Fig.3).CuandCrwerecorrelatednegativelywithPC2(Fig. 3). In terms of water chemistry,MANOVA showed astatistical difference between stream types (F = 16.923;df = 2, 29; p = 5.6 × 10−11). ANOVA (p < 0.05) showed

Ni,Zn, andMnwere statistically different amongall streamtypes (Table 3). Al, Ba, Cu, Co, Cr, and Fe concentrationswere statistically higher inAMDstream types compared totreated and reference stream types, while pH and alkalinityconcentrationswere statistically higher in treated and refer-ence stream types compared to AMD stream types(Table 3). Specific conductance, SO4

2−, Ca, and Mg con-centrations were statistically higher in AMD and treatedstream types compared to reference stream types, and Cl−,Na, and Se concentrations were all statistically equivalentamong stream types (Table 3).

Acid loads andnet acidity calculated at themouthof thewatershed and all major tributaries receiving AMD treat-ment declined, except at Laurel Run. Specifically, the acidloadat themouthofAbramCreekwasreducedfrom330 to34 t/year. Emory Creek was observed to have the greatestreduction in net acidity compared to other treated tribu-taries at −220 t/year. Laurel Run was observed to gainapproximately 16 t/year of acidity (Table 4).We observedno statistical difference in RVHA scores among streamtypes (MANOVAF = 1.0648; df = 2, 30; p = 0.4161).

Benthic macroinvertebrates and fish

Biological conditions varied widely throughout the wa-tershed. NMDS ordinations indicate that invertebrateand fish assemblages are responding positively to waterchemistry improvements (Figs. 4 and 5). For macroin-vertebrates, percent Ephemeroptera increased stronglyat treated sites (Fig. 4c). Taxa predominantly correlatedto improvements were from the family Baetidae, specif-ically genera Plauditus and Acentrella (Fig. 4d). Theglobal ADONIS revealed differences in both macroin-vertebrate (F = 2.4558; p = 0.004; R2 = 0.14) and fish(F = 6.0756; p = 0.001; R2 = 0.38) assemblages fromdifferent stream types. Subsequent pairwise compari-sons found that macroinvertebrate assemblages fromAMD streams were statistically different from treatedstreams (F = 2.4063; p = 0.033; R2 = 0.09) and referencestreams (F = 3.0205; p = 0.013; R2 = 0.15), but treatedstreams were not statistically different compared to ref-erence streams (F = 1.8881; p = 0.07; R2 = 0.11). ADO-NIS pairwise comparisons for fish communities re-vealed that fish communities from AMD streams werestatistically different from treated streams (F = 4.1008;p = 0.005; R2 = 0.24) and reference streams (F = 5.9776;p = 0.004; R2 = 0.40), and treated streams were statisti-cally different compared to reference streams(F = 7.758; p = 0.001; R2 = 0.30).

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Paired t tests showed that both WVSCI (p = 0.0001,df = 12) and GLIMPSS (p = 0.0002, df = 12) increasedstatisticallypost-treatment.ANOVAfoundthatGLIMPSSand the EPT genus richness metric were statistically dif-ferentamongallstreamtypes(Table5).The%Chironomidmetric was statistically higher in AMD streams comparedto treatedand reference streams,while%EPTfamilies andWVSCI were statistically higher in treated and referencestreams compared to AMD streams (Table 5).

We found fish at nine stream segments that previouslyhad none, two of which had brook trout (Salvelinusfontinalis; 11 at Emory Creek and 9 at Glade Run) andoneofwhichhadsmallmouthbass(Micropterusdolomieu;26 at Abram Creek upstream of Emory Creek). All sitesthat previously lacked fish had creek chub (Semotilus

atromaculatus).ANOVAtests found that fish species rich-ness was statistically higher in treated and referencestreams compared to AMD streams, while the proportionof macro-omnivores and gravel spawning species werestatistically different among all stream types. Also, theproportion of invertivore-piscivore individuals was statis-tically higher in treated streams compared to AMD andreference streams (Table 5).

Ecological units

We estimated that theAbramCreekwatershed historicallypossessed 55.6 km of overall fishery EUs (Table 6 andFig. 6a), 55.8 km of macroinvertebrate diversity EUs(Table 6 and Fig. 6b), 49.4 km of brook trout fishery EUs

Table 3 Means and standard deviations (SD) of water chemistry parameters and principal component (PC) 1, 2, 3, and 4 scores for eachstream type

Stream type

AMD (n = 14) Treated (n = 13) Reference (n = 4)

Mean SD Mean SD Mean SD

pH 6.25a 0.74 7.02b 0.45 7.29b 0.42

Specific conductance 313.93a 69.59 386.85a 90.40 118.8b 68.69

Alkalinity 4.03a 3.39 15.31b 7.84 24.57b 13.75

Al 0.47a 0.82 0.03b 0.04 0.01b 0.01

Ba 0.07a 0.02 0.03b 0.00 0.04b 0.01

Cu 0.01a 0.00 0.01b 0.00 0.01b 0.00

Cl− 4.35 2.32 5.05 2.82 6.45 4.89

Co 0.06a 0.04 0.01b 0.01 0.01b 0.00

Cr 0.02a 0.01 0.00b 0.00 0.01b 0.01

Ca 26.35a 6.21 39.41a 16.26 11.55b 4.80

Na 3.88 1.88 5.72 1.63 3.86 2.76

Ni 0.05a 0.03 0.03b 0.01 0.01c 0.00

Se 0.06 0.05 0.03 0.00 0.04 0.01

Zn 0.10a 0.07 0.03b 0.03 0.01c 0.00

SO2−4

113.11a 30.6 136.61a 61.13 11.48b 1.50

Fe 0.51a 0.81 0.09b 0.15 0.03b 0.00

Mg 9.23a 1.94 12.29a 5.39 2.35b 0.57

Mn 1.82a 1.15 0.73b 0.48 0.01c 0.00

PC1 2.62a 1.34 −1.11b 1.21 −4.44c 1.01

PC2 -0.77a 1.13 1.89b 1.07 −2.77c 1.34

PC3 -0.25 1.57 0.20 0.83 0.17 0.98

PC4 0.23 1.27 −0.20 0.88 −0.13 0.69

Means with different letters among stream types are statistically different (p < 0.05; analysis of variance, Tukey post-test). Means arereported in milligrams per liter. Specific conductance is reported in microsiemens per centimeter, and alkalinity is reported in milligrams perliter CaCO3 equivalents

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(Table 6 and Fig. 6c), and 20.7 km of stocked trout fisheryEUs (Table 6 and Fig. 6d) throughout the study area. As aresult of AMD impacts, pre-treatment EUs indicate thatonly 30% of the historic overall fishery value, 42% of themacroinvertebrate diversity, 28% of the brook trout, and14% of the stock trout fishery remained in 2008 (Table 6and Fig. 6). The watershed-based remediation plan devel-opedand implementedwasexpected to recover66%of thehistoric overall fishery value, 67% of the macroinverte-brate diversity, 61% of the brook trout, and 92% of thestock trout fishery (Table 6 andFig. 6). The observed post-treatment EUs indicate that 52% of the historic overall

fishery value, 74% of the macroinvertebrate diversity,33%ofthebrooktrout,and72%ofthestockedtrout fishery(Table 6 and Fig. 6) have been recovered 3 years afterremediation efforts were implemented.

The two-sample Kolmogorov-Smirnov tests suggestthat the observed post-treatment macroinvertebrate di-versity, stocked trout fishery, and overall fishery EUsaccumulated at a statistically equivalent rate along theriver compared to the predicted post-treatment macroin-vertebrate diversity, stocked trout fishery, and overallfishery EUs (p = 0.6465, 0.1717, and 0.0966, respec-tively). However, the observed post-treatment brook

Fig. 3 Bivariate scatter plot ofprincipal component (PC) 1 and 2scores for each water chemistrysample overlaid with stream type.A acid mine drainage (AMD), Ttreated, and R reference streamtypes. Chemical parameters withhigh (>|0.5|) factor loadings oneach PC are shown on thecorresponding axis. Cond specificconductance

Table 4 Acid, alkalinity, and net acidity loads pre- (2008) and post-treatment (2013) at the mouth of the watershed andmajor tributaries thatreceived treatment (values in tons/year CaCO3 equivalents)

Site 2008 2013 Δ net acidity

Acid load Alkalinity load Net acidity Acid load Alkalinity load Net acidity

Abram Creek at mouth 228.0 330.3 −102.3 34.3 1156.3 −1122.0 −1019.6Emory Creek 130.4 30.2 100.2 34.4 154.4 −120.0 −220.3Glade Run 13.6 11.4 2.2 4.1 118.7 −114.6 −116.8Laurel Run 41.4 36.0 5.4 39.2 18.2 21.0 15.6

Little Creek 56.8 3.6 53.3 1.1 74.5 −73.3 −126.6Abram Creek headwaters 25.6 0 25.6 2.4 78.4 −76.0 −101.6

Negative values of Δ (delta) net acidity indicate decline

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trout fishery EUs accumulated at a statistically lowerrate compared to the predicted post-treatment brooktrout fishery EUs (p = 0.0009) (Table 6 and Fig. 6).

Discussion

In this study, we evaluated expected outcomes of a water-shed scale remediation initiative.We documented notableimprovements in environmental conditions related to

AMD treatment, but biotic responses, especiallymeasuresof fishery quality, fell short of meeting expectations, de-spite evidence of reconnection of the stream network.Consequently, in this study,wehave related improvementsin watershed conditions to ecological benefits expectedprior to remediation actions.

Our finding of improved water quality as a result ofAMD treatment is consistent with numerous studies con-ducted in this region (Trout Unlimited (TU) 2011, Simonet al. 2012). We characterized the overall chemical

Fig. 4 Nonmetric multidimensional scaling (NMDS) ordinationof benthic macroinvertebrate samples (Bray-Curtis distancecoefficient) in two dimensions showing sites labeled by streamtype (a), water chemistry vectors (b), macroinvertebrate metrics(c), and weightedmean positions of selected taxa (d). Stress = 0.15in the three-dimensional solution. Stream type abbreviations as inFig. 3. Alk alkalinity, Cond specific conductance, PerDom %

dominance, PerE%Ephemeroptera, PerChiron%Chironomidae,EPT Ephemeroptera, Plecoptera, Trichoptera, GRICH genus-levelrichness,WVSCIWest Virginia Stream Condition Index (a family-level multimetric index of biotic integrity),GLIMPSSGenus LevelIndex of Most Probable Stream Status (a genus-level multimetricindex of biotic integrity). ADONIS p value = 0.004

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response to AMD treatment as a transition from metal-laden acidic waters to hard waters with elevated specificconductanceandSO4

2−concentrations.Although thisnewwater chemistry signature is different from reference con-ditions, biological assemblages have improved with thesechemical improvements.

In our study, the genera predominantly responsiblefor improvements in macroinvertebrate assemblages at

treated sites were from the family Baetidae, specificallythe genera Plauditus and Acentrella. An explanation ofthe improved but altered assemblages is that treatedstreams were being colonized by pioneer invertebrateassemblages. Vieira et al. (2004) characterized Baetidmayflies as being strong larval dispersers and found aBaetid species to rapidly recolonize and dominate ben-thic communities during early post-disturbance years.

Fig. 5 Nonmetric multidimensional scaling (NMDS) ordinationof fish samples (Bray-Curtis distance coefficient) in two dimen-sions showing sites labeled by stream type (a), water chemistryvectors (b), fish metrics (c), and weighted mean positions ofselected species (d). Stress = 0.11 in the two-dimensional solution.Stream type abbreviations as in Fig. 3.Cond specific conductance,BenthicSpp no. of benthic species, ProTol proportion tolerant,SRICH species-level richness, SenSRICH sensitive species rich-ness, ProI.P proportion of invertivore-piscivores, ProM.O propor-tion of macro-omnivores, ProGSpawn proportion of gravel

spawning species, SEAT Semotilus atromaculatus (creek chub),SAFO Salvelinus fontinalis (brook trout), ETFL Etheostomaflabellare (fantail darter), COCA Cottus caeruleomentum (blueridge sculpin), RHAT Rhinichthys atratulus (eastern blacknosedace), CACO Catostomus commersonii (white sucker), LECYLepomis cyanellus (green sunfish), MIDO Micropterus dolomieu(smallmouth bass), CAAN Campostoma anomalum (stoneroller),AMRU Ambloplites rupestris (rock bass). ADONIS pvalue = 0.001

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Additional studies examining successional sequenceshave found the family Baetidae to be early colonistsafter catastrophic watershed scale disturbances (Floryand Milner 2000, Zuellig et al. 2002). Strong dispersalcapability coupled with low habitat specificity definesthese taxa as pioneer species (Gore 1982). Thus, it isevident that benthic macroinvertebrate assemblages areimproving given the improved chemical environmentwe have characterized in the Abram Creek watershed.

Fish assemblages have also improved. However, fishassemblages sampled from treated reaches were quitedifferent compared to reference reaches. Despite

differences in community structure among stream types,we found fish present at nine assessment sites whichpreviously had none. All sites that previously lacked fishhad creek chub, the only species of fish found in upperAbram Creek; however, further downstream from thethree lime dosers, we observed brook trout, smallmouthbass, and eastern blacknose dace (Rhinichthysatratulus). Brook trout were found at two sites whichpreviously had none. In 2007, before project comple-tion, the Johnnycake Run tributary network was the onlyintact fishery remaining in the Abram Creek drainage.This movement of a sensitive species into stream

Table 5 Means and standard deviations (SD) of benthic macroinvertebrate and fish metrics for each stream type

Water quality type

AMD (n = 14) Treated (n = 13) Reference (n = 4)

Mean SD Mean SD Mean SD

WVSCI 47.75a 17.64 67.39b 13.76 85.17b 1.95

GLIMPSS 26.03a 15.07 41.50b 14.18 66.70c 6.82

EPT genus richness 5.36a 4.75 9.85b 4.56 16.80c 3.96

Genus richness 13.00a 7.68 19.23ab 7.70 27.40b 1.52

% EPT families 28.87a 25.28 59.13b 23.00 61.75b 8.94

% Chironomidae 45.68a 18.44 25.95b 17.65 21.11b 4.39

% 2 dominant 66.24a 12.78 61.20a 12.08 44.40b 11.13

Fish species richness 0.73a 1.75 2.77b 1.96 3.75b 2.43

# of benthic species 0.00a 0.00 0.08a 0.28 0.50b 0.53

Sensitive species richness 0.13a 0.35 0.23a 0.44 0.75b 0.46

Proportion of tolerant individuals 0.17a 0.36 0.86b 0.28 0.78b 0.22

Proportion of I-P individuals 0.15a 0.33 0.61b 0.3 0.13a 0.12

Proportion of macro-omnivores 0.05a 0.15 0.31b 0.28 0.71c 0.25

Proportion of gravel spawning species 0.05a 0.13 0.32b 0.30 0.76c 0.26

Means with different letters among stream types are statistically different (p < 0.05; analysis of variance, Tukey post-test)

WVSCI West Virginia Stream Condition Index, GLIMPSS Genus Level Index of Most Probable Stream Status, EPT Ephemeroptera,Plecoptera, Trichoptera, I-P invertivore-piscivore

Table 6 Ecological units (EUs) in stream kilometers calculated for each aquatic life endpoint

Aquatic life endpoints HEUs Pre-EUs LEUs REUs FEUs Post-EUs K-S Test p values

Macroinvertebrate diversity EU 55.8 23.3 (42%) 32.5 (58%) 14.0 (25%) 37.3 (67%) 41.1 (74%) 0.65

Overall fishery EU 55.6 16.7 (30%) 38.9 (70%) 19.8 (36%) 36.5 (66%) 28.9 (52%) 0.10

Brook trout fishery EU 49.4 13.8 (28%) 35.6 (72%) 16.4 (33%) 30.2 (61%) 16.2 (33%) 0.001

Stocked trout fishery EU 20.7 2.9 (14%) 17.8 (86%) 16.2 (78%) 19.1 (92%) 14.8 (72%) 0.17

Values in parentheses indicate the percent of HEUs

HEUs historic EUs, Pre-EUs pre-treatment EUs, LEUs lost EUs, REUs recoverable EUs, FEUs future EUs (i.e., predicted), Post-EUs post-treatment EUs, K-S test two-sample Kolmogorov-Smirnov test

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segments which previously lacked fish suggests thatpreviously isolated, poor-quality streamswere improvedand reconnected to distal sub-watersheds via improve-ments to the mainstem. McClurg et al. (2007) found thatlimestone treatment did not fully recover total fish bio-mass to reference conditions in acid-impacted water-sheds of the Allegheny Plateau. They accredited thisshortcoming to the isolation of treated streams in anetwork of acidic watersheds. Consequently, streamremediation plans should focus on recovering streamecosystems as connected networks rather than isolatedreaches (McClurg et al. 2007).

Despite obvious improvements in water quality andecological communities, we did not observe watershedscale recovery as expected. While the macroinvertebratediversity EUs exceeded expectations, the brook trout,stocked trout, and overall fishery EUs did not meet ourexpected predictions. Several details may explainwhy the

observed conditions fell short of our predicted outcomesfor fish communities. First, AMD treatment did not de-crease SO4

2− concentrations or specific conductance tolevels comparable to reference conditions. Sulfate concen-trations are not expected to decrease with the treatmenttechnologies used, andhigh levels of specific conductanceare common for treated mine water (DeNicola andStapleton 2016). Pond et al. (2008) found biological im-pairment when specific conductance was greater than500 μS/cm. A more recent study observed biological im-pairment when specific conductance reached 250 μS/cm(Merriam et al. 2011). Freund and Petty (2007) observed anegative correlation between SO4

2− concentration and bi-otic indices. These results suggest that elevated specificconductance and SO4

2− concentrations may restrict bio-logical communities from recovery. Future remediationplans should focus efforts on the reduction of SO4

2− andspecific conductance concentrations.

0

10

20

30

40

50

60

)m

k(sti

nu

yre

hsif

llar

ev

oe

vital

um

uC

Historic EUs

Pre-treatment EUs

Predicted post-treatment EUs

Observed post-treatment EUs

a55.6 km

36.5 km

28.9 km

16.7 km

Cu

mu

lative

div

ers

ity u

nits (

km

)

b55.8 km

41.1 km

37.3 km

23.3 km

0 10 20 30 40 50 60

0

10

20

30

40

50

60

)m

k(sti

nu

tu

o rtk

oor

be

vital

um

uC

c

49.4 km

30.2 km

16.2 km

13.8 km

0 10 20 30 40 50 60

Cu

mu

lative

sto

cke

d tro

ut u

nits (

km

)

d

20.7 km

19.1 km

14.8 km

2.9 km

Cumulative stream kilometers

Fig. 6 Cumulative EUs in stream kilometers for a (overall fishery), b (macroinvertebrate diversity), C (brook trout fishery), and d (stockedtrout fishery) throughout the Abram Creek watershed in the downstream direction

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Secondly, treatment at Laurel Runwas not effective andnet acidity increased, probably because of current miningin the sub-watershed. A mining company holds a refusedisposal permit, and AMD seeps above the stream areaffecting the limestone sand treatment (J. Baczuk; WestVirginia Department of Environmental Protection, person-al communication). Laurel Run was also the only sitereceiving AMD treatment not to have fish despite a min-imal increase in benthic macroinvertebrate IBI scores.Several other studies have observed little to no recoveryand delayed recovery of invertebrate communities follow-ing remediation as well (Gunn et al. 2010; Louhi et al.2011; DeNicola and Stapleton 2016). These observationsare often attributed to varying levels of AMD inputs andinconsistent treatment conditions, episodic acidification,and scarcity of organic matter input (Bradley andOrmerod 2002; Simmons et al. 2005; Gunn et al. 2010;DeNicola and Stapleton 2016). Thus, current AMD treat-ment may not be enough to mitigate active mining activ-ities in this case; therefore, we recommend that additionaltreatment in Laurel Run be implemented as an importantnext step in the adaptive watershed management cycle.

Another limiting factor was the exceptional length ofthe chemical mixing zone. In general, we found thatobserved post-treatment EUs accumulated downstreamof treatment at a much slower rate than predicted post-treatment EUs (Fig. 6), with the exception of the cumu-lative macroinvertebrate diversity EU (Fig. 6b). Forexample, our remediability functions predicted thatoverall fishery EUs would start accruing after riverkilometer 7.4, at the point where cumulative DA be-comes capable of supporting a fishery (Fig. 6a). Post-treatment analysis indicates that overall fishery EUs donot substantially start accruing until river kilometer17.2, at the point where WVSCI scores became capableof supporting a fishery (Fig. 6a). McClurg et al. (2007)found evidence that a sacrificial zone of ecologicalimpairment existed 2–3 km from limestone sand treat-ment in acid deposition-impacted watersheds of WV.Our finding of brook trout in Emory Creek approximate-ly 2.5 km downstream from the limestone sand is con-sistent with this impairment threshold. Water chemistrydata from Emory Creek is characteristic of acidic con-ditions caused by acid deposition; there are no AMLs orsurface mines upstream. Acid precipitation severely im-pairs mountain streams in this region and is distin-guished by depressed pH, very low specific conduc-tance, and elevated concentrations of dissolved Al insurface waters (Merovich et al. 2007; Driscoll et al.

2011). The limestone sand applied to Emory Creek isneutralizing the acid deposition from the left fork of theEmory Creek headwaters helping to keep the aciditylower at the mouth of the Emory Creek drainage. How-ever, sacrificial zones associated with AMD treatmentare much greater because dissolved metal concentra-tions and overall water quality tend to be worse than inwatersheds impacted solely by acid precipitation(Merovich et al. 2007). Consequently, the type of pol-lution being treated (i.e., acid deposition or AMD) anddistance to the type of treatment should be factored intoremediability weighted functions that calculate recover-able EUs under a given remediation alternative.

Finally, another limiting factor is the regional context inwhich Abram Creek watershed is located. Variability inmetacommunity dynamics (i.e., species sorting and masseffects) probably influenced our ability to predict biologicalrecoveryatthewatershedscale(Merriametal.2015).Beforetreatment began, we estimated that only 30% of the overallfishery value in the watershed remained, and this was iso-lated toJohnnycakeRun,asmall sub-watershedsurroundedbyimpairedwaters. Improvedwatershedscalewaterqualityreconnected JohnnycakeRun toAbramCreek, but regionalconditions in the Potomac may limit the ability of AbramCreekwatershed to recover. TheNorth Branch of the Poto-mac River basin is well known for its history of problemsassociated with AMLs. While conditions in the NorthBranch of the Potomac have greatly improved and nowsupport a put-and-take trout fishery, biological conditionsremain erratic and sub-optimal (Hansen et al. 2010). Localcommunities are a product of the regional species pool(Sundermann et al. 2011) and therefore unsupportive bio-logical factors such as the lack of local (alpha) or regional(beta) diversity may restrict fisheries expectations frombeing realized in a timely manner at the watershed scale inAbram Creek. Restoration should seek to prioritize effortstoward needs within good regions rather than poor regions.Amultiscale approach ensures that restoration efforts buildon existing high-quality conditions (Merovich et al. 2013).Nevertheless, restoration effort inAbramCreek is a successin termsof improvingwaterqualityand localenvironmentalconditions.

TheuseofEUsinouranalysisallowedus toquantify theresponse of ecological conditions to treatment at both thelocal and watershed scale. By assigning an ecologicalcurrency to individual segment-levelwatersheds, wewereable to document the effect of treatment on the ecologicalrecovery of specific drainages, as well as the cumulativebenefits of treatment to the streamnetwork.Our analysis is

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the first that we know that provides a means to evaluateremediation outcomes with those expected. While ourweighting functions for EU calculation represent hypoth-eses of watershed processes, they are our best approxima-tion from which to develop expectations. Further work torefine these functions and develop additional neededmodels would be useful.

There are a number of reasons why having explicitexpectations of remediation outcomes is useful. First, inthe initial phases of designing treatment scenarios at thewatershed scale, quantifying expected benefits aidsidentification of treatment technologies and locationswithin the watershed to maximize remediation benefits(Petty et al. 2008). Once the remediation plan is under-way, comparisons between current conditions and ex-pected outcomes provide information to direct aposteriori adaptive management actions where there isthe greatest need. For example, where watershed scalebenefits are not accumulating as predicted, improve-ment efforts can be directed at those treatment locationsresponsible for under-performance. Finally, comparingobserved performance against expected outcomesamong the various aquatic life end points can suggestwhich watershed management goals (e.g., brook troutvs. stocked trout, etc.) are most feasible given the con-ditions in the region. A similar process is possible forother end points depending on the regional conditions orwatershed objectives (e.g., warmwater fisheries).

Conclusions

We were able to complete the adaptive watershed man-agement cycle for the Abram Creek watershed remedi-ation plan. This post-treatment assessment documenteda reconnection of the watershed and significantly im-proved ecological conditions in Abram Creek. Theseimprovements were notably observed downstream ofliming dosers and limestone sand dump sites throughoutthe watershed, with the exception of Laurel Run whichmay have been compromised due to ongoing miningactivity. Only 3 years passed since project completionand communities that reflect reference conditions mayrequire more time. We demonstrated that it is possible to(1) quantify the degree of ecological loss from mining-related stressors on stream ecosystems, (2) estimate theamount of ecological habitat that can be recoveredthrough remediation programs, and (3) quantify thedegree of post-treatment ecological recovery at both

the stream segment and watershed scale. We expect thisgeneral framework developed for mined watersheds canbe translated to other anthropogenic stressors. Finally,we believe that our framework for evaluating expectedoutcomes will provide an accounting system to identifywhere adjustments are needed to bring remediation bet-ter in line with expectations. Doing so will expediteremediation, rather than letting poor responses unknow-ingly lag. Continued long-term monitoring of theAbram Creek watershed is needed to further evaluateremediation progress valuable toward advancing thescience of watershed remediation ecology.

Acknowledgements We thank Donna Hartman, Eric Merriam,Eric Miller, Brock Huntsman, and Alison Anderson for their helpin field sampling and laboratory analysis. We thank Jim BaczukfromWVDEPOffice of AbandonedMine Lands and Reclamationfor sharing his expertise and overlooking the operation and main-tenance for the Abram Creek watershed remediation project. Thiswork was funded, in part, by the Appalachian Research Initiativefor Environmental Science, the West Virginia Water ResearchInstitute, and West Virginia University, School of Natural Re-sources. All sampling was approved by The Institutional AnimalCare and Use Committee (IACUC) of West Virginia University(most recent protocol number 11–0507).

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