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Home My WebLink About20080868 Ver 1_Monitoring Report_20130315PotashCorpr' Helping Nature Provide Federal Express March 13, 2013 Ms. Cyndi Karoly Supervisor, Wetlands and Stormwater Branch Division of Water Quality North Carolina Dept. of ENR 1650 Mail Service Center Raleigh, NC 27699 -1650 Re: Whitehurst Creek 2012 Sampling Report Dear Ms. Karoly: PotashCorp -Aurora Enclosed are two copies of the " Whitehurst Creek West Prong Aquatic Macroinvertebrate Survey and Water Quality Analysis: 2012 Mitigation Channel Report ". This is the first report utilizing the new monitoring protocol involving two new downstream reference stations, as described in our December 14, 2011 submittal to you. Please call me at (252) 322 -8249 or a -mail me at ifurnessL4csphosphate.com if you have any questions. Sincerely, n Jeffrey C. Furness Senior Scientist Attachment PC: Amy Adams — DWQ, Washington Sam Cooper — CZR, Wilmington 23 -01- 004 -26 R. M. Smith M. Brom M w /encl AR 1 2013 w/o encl. kR . w /encl. w /summary w /summary 1530 NC Hwy 306 South, Aurora, NC USA 27806 T (252) 322 -4111 PotashCorp. I www.potashcorp.com WHITEHURST CREEK WEST PRONG AQUATIC MACROINVERTEBRATE SURVEY AND WATER QUALITY ANALYSES: 2012 ANNUAL MITIGATION CHANNEL REPORT Prepared for: PCS PHOSPHATE COMPANY, INC. Environmental Affairs Department Aurora, North Carolina Prepared by: CZR INCORPORATED 4709 College Acres Drive, Suite 2 Wilmington, North Carolina February 2013 MAR 1 5 2013 NR - WA WHITEHURST CREEK WEST PRONG AQUATIC MACROINVERTEBRATE SURVEY AND WATER QUALITY ANALYSES: 2012 ANNUAL MITIGATION CHANNEL REPORT Prepared for PCS PHOSPHATE COMPANY, INC. Environmental Affairs Department Aurora, North Carolina Prepared by CZR INCORPORATED 4709 College Acres Drive, Suite 2 Wilmington, North Carolina February 2013 WHITEHURST CREEK WEST PRONG AQUATIC MACROINVERTEBRATE SURVEY AND WATER QUALITY ANALYSES: 2012 ANNUAL MITIGATION CHANNEL REPORT TABLE OF CONTENTS 322 Comparison of 2012 Results and New Reference Stations 13 40 SUMMARY 16 REFERENCES 17 Paqe COVER SHEET i TABLE OF CONTENTS LIST OF TABLES LIST OF FIGURES LIST OF APPENDICES iv 1 0 INTRODUCTION 1 11 History 1 12 Purpose 3 1 3 Project Site 3 2 0 METHODS 4 21 Physical Characteristics and Water Quality 4 22 Aquatic Macroinvertebrates 4 30 RESULTS AND DISCUSSION 5 31 Physical Habitat and Water Quality 5 32 Aquatic Macroinvertebrates 7 3 2 1 2012 Aquatic Macroinvertebrate Survey 7 322 Comparison of 2012 Results and New Reference Stations 13 40 SUMMARY 16 REFERENCES 17 LIST OF TABLES Table 1 Description of conditions during aquatic macroinvertebrate surveys in the Whitehurst Creek West Prong mitigation channel tenth -year (2012) and first year in two downstream reference stations, Beaufort County, North Carolina 2 Taxa richness of aquatic macroi nve rte b rates (by group) for the Whitehurst Creek West Prong mitigation channel tenth -year (2012) survey and first year for two downstream reference stations, Beaufort County, North Carolina 3 Tenth -year (2012) aquatic macroi nverte b rate survey of the Whitehurst Creek West Prong mitigation channel and first year for two downstream reference stations, Beaufort County, North Carolina 4 Comparison of 2012 aquatic macroi nverteb rate communities for the Whitehurst Creek West Prong mitigation channel tenth -year (2012) survey and first year for two downstream reference stations, Beaufort County, North Carolina LIST OF FIGURES Figure 1 WHITEHURST CREEK BENTHIC SAMPLING STATIONS LIST OF APPENDICES Appendix A AQUATIC MACRO INVERTEBRATE TAXA DOCUMENTED IN UPPER WHITEHURST CREEK IN THE WHITEHURST CREEK WEST PRONG MITIGATION CHANNEL DURING 2003 THROUGH 2012 SURVEYS AND IN 2012 SURVEY OF TWO DOWNSTREAM REFERENCE STATIONS B SELECTED PHOTOGRAPHS FROM 2012 SURVEYS IN WEST PRONG MITIGATION CHANNEL AND DOWNSTREAM REFERENCE SITES Paqe .14 Paqe of WHITEHURST CREEK WEST PRONG AQUATIC MACROINVERTEBRATE SURVEY AND WATER QUALITY ANALYSES: 2012 ANNUAL MITIGATION CHANNEL REPORT 1 0 INTRODUCTION Since 2003, two stations have been sampled in February and July for aquatic macroinvertebrates in the West Prong mitigation channel of Whitehurst Creek and compared to the 1992 baseline results (CZR Incorporated 1993) Station 1 is located near the downstream end of the West Prong mitigation channel and Station 2 is located upstream of Station 1 in the upper end of the mitigation channel At the suggestion of the North Carolina Division of Water Quality (NCDWQ), two new reference stations were proposed and accepted for additional aquatic macroinvertebrate surveys The two new reference stations, Stations A and B, are located downstream of the West Prong mitigation channel in the historical portion of Whitehurst Creek, but upstream of estuarine marsh Station A is located downstream of the new railroad bridge across Whitehurst Creek and Station B is located upstream of the same bridge All four station locations are depicted on Figure 1 The new monitoring protocol for the four stations in Whitehurst Creek ceases collection of fish data and monthly channel water quality measurement by PCS Phosphate Company, Incorporated as has occurred in the West Prong mitigation channel since 2003 The new aquatic macroinvertebrate monitoring at the four stations is to follow the same methodology and protocol as has been followed in the West Prong mitigation channel since 2003, however, annual data from Stations 1 and 2 will be compared to annual data from Stations A and B instead of the 1992 baseline Selection of the two proposed Stations A and B was based on the station having a similar degree of canopy cover and similar shrubby creek edge as found at the current Stations 1 and 2 The most downstream proposed station (Station A) is located in the transition zone between bottomland /swamp forest and the zone of active tree death concomitant with sea level rise The most upstream proposed station (Station B) is located at the edge of the maintained power line and the bottomland /swamp forest community 1 1 History On 24 April 1992 PCS Phosphate Company Inc (PCS Phosphate) (then Texasgulf) submitted an application for a 401 Water Quality Certification to the North Carolina Division of Water Quality (DWQ, formerly Division of Environmental Management) of the North Carolina Department of Environment and Natural Resources (NCDENR) to impact a portion of the channelized drainage of upper Whitehurst Creek, Beaufort County, North Carolina Approval of the 401 (Certification No 2748) was issued on 30 June 1 1992, and a temporary mitigation channel was constructed A modification to the 401 Certification, to relocate a portion of this temporary mitigation channel, was requested on 15 December 1994 and approved on 30 May 1995 A second modification was requested on 28 May 1996, which involved leaving the 1992/1995 Whitehurst Creek mitigation channel in place, construction of the required permanent mitigation channel (West Prong) through reclaimed land, and a change in the date for the channel system to be merged and completed This request was approved by DWQ and resulted in the issuance of a modified 401 Certification on 12 December 1996 Finally, a change in macroinvertebrate survey protocol was approved in a January 2012 Office of Administrative Hearings (OAH) Settlement Agreement between NCDENR and PCS Phosphate Baseline conditions in historical upper Whitehurst Creek gathered during 1992 surveys by DWQ and CZR Incorporated (CZR) are described in the baseline report (CZR Incorporated 1993a) A detailed description of the temporary mitigation channel constructed in 1992 is found in Appendix B of the 1992 baseline aquatic survey report (CZR Incorporated 1993b) Results of monitoring in the temporary upper Whitehurst Creek mitigation channel are contained in a series of reports (CZR Incorporated 1994 -1999, 2000a, and 2000b) The West Prong, a 10 -foot wide channel and 100 -foot wide floodplain through reclaimed land was constructed in 1998, and the floodplain was planted with mixed hardwood seedlings and saplings The channel and floodplain are in the approximate location of the historical upper Whitehurst Creek western prong The new West Prong was connected to the undisturbed portion of Whitehurst Creek in September 2002 12 Purpose This is the tenth report in a series of mitigation monitoring reports for the West Prong of Whitehurst Creek, and presents the results of the 2012 aquatic macroinvertebrate surveys conducted by CZR for PCS Phosphate Results from the nine previous years of aquatic macroinvertebrate and fish surveys are found in annual monitoring reports (CZR Incorporated 2004 -2012) This sampling is required as a condition of the revised 401 Water Quality Certification No 2748 issued by DWQ and the January 2012 OAH Settlement Agreement between NCDENR and PCS Phosphate 1 3 Project Site The vicinity of the 1992 upper Whitehurst Creek mitigation channel, the undisturbed portion of Whitehurst Creek and the West Prong are shown in Figure 1 The West Prong is in the PCS Phosphate mine site west of NC Highway 306 and Old Brantley Swamp Road (S R 1941) The mitigation channel and floodplain have been designed to restore and enhance the ecological functions associated with the wetlands and surface waters of the historical upper Whitehurst Creek drainage 3 2 0 METHODS 21 Physical Characteristics and Water Quality Temperature, conductivity, salinity, dissolved oxygen, and pH were measured twice annually by CZR at each benthos sampling station (described below) at the time of the biological surveys Other parameters assessed by CZR at the time of biological sampling included substrate composition, water depth, canopy cover, aufwuchs (algal, bacterial, fungal, and meiofaunal growth upon solid surfaces), flow estimates, and bank erosion 22 Aquatic Macroinvertebrates Two 600 -foot monitoring stations for fish and aquatic macroinvertebrate surveys were established in the mitigation channel in 2003 (Figure 2) Station 1 was located near the downstream end of the West Prong mitigation channel and Station 2 was located upstream of Station 1 near the terminus of the mitigation channel The macroinvertebrate sampling methodology and reporting standards were based on the Swamp Method protocol used by DWQ during sampling of Whitehurst Creek in February 1992 (CZR Incorporated 1993b, NCDENR 2001a) in an effort to maintain consistency in collection and analysis of data The 2006 Standard Operating Procedures for Benthic Macroinvertebrates publication by NCDENR was consulted for updates on the Swamp Method and was found to require the same sampling techniques as currently practiced by CZR (NCDENR 2006a ) In accordance with the protocol, nine standing sweep net samples for macroi nve rte b rates were collected in the floodplain at the downstream end of each station and hand -sorted in the field Collected individuals were preserved in 10 percent formalin Additional specimens were collected from log washes and rubs as well as incidental captures In the lab, all specimens were identified to the lowest reasonable taxa as described in Brigham et al (1982) Regardless of the number of individuals in a genus, most unidentified taxa encountered were identified to the genus "sp " level Taxa unidentified to species level are not counted in taxa richness totals when the same genus is already represented either during a season or at a sampling station When the taxa are tallied for commonality with reference site taxa, any taxa encountered during monitoring that is identified to species level is considered a match with reference taxa that was identified only to genus level for those taxa Similarly, any taxa encountered during monitoring that is within a family identified in reference stations and that has no other members identified is also considered a match Biotic Index (BI) values are calculated for winter samples only as recommended by DWQ (NCDENR 2001a, NCDENR 2006a) The BI values allow assessment of temporal changes in biological integrity as well as comparison of biological integrity in Whitehurst Creek among sampling efforts This bioclassification is based on the tolerance of the macrobenthic community as summarized by the North Carolina Biotic Index (NCBI) The NCBI is calculated by summing the tolerance values of individual taxa (family or genera in some cases), multiplied by their abundance value, to give an average tolerance value Tolerance values for either individual species, or the final biotic value of a 4 particular site, range from 0 to 10 with higher numbers indicating more tolerant species (or communities) and more polluted conditions If a taxon is found which does not have a tolerance value, Larry Eaton, the senior macroinvertebrate specialist with NCDWQ, will assign a value CZR then calculates the BI However, not all taxa identified are assigned tolerance values because there may not be enough ecological information to determine a value In addition, Ephemeroptera, Plecoptera, and Trichoptera taxa richness (EPT richness) is tabulated Like the BI, the EPT richness metric is often used as an indicator of habitat quality, as high EPT richness is considered an indicator of good ecosystem health Commonly, coastal plain streams have a lower EPT richness than piedmont or mountain streams because of slow or low flows and other unique characteristics of these streams To compare the similarity of the 2012 reference and 2012 macroinvertebrate communities, the Jaccard coefficient of community similarity was used (Brower and Zar 1984) The Jaccard index (C) is defined as Cj= c /(s1+s2 -c), where c= number of genera in common and s1, s2 are the total number of genera in community 1 and 2, respectively The Jaccard index of community similarity ranges from 0 0 (completely dissimilar populations) to 1 0 (identical populations) 3 0 RESULTS AND DISCUSSION 31 Physical Habitat and Water Quality Water quality information and site descriptions collected by CZR during 2012 biological sampling (22 February and 25 July) are presented in Table 1 Due to high water, habitat characterization for depth and water quality parameters was performed on the inundated West Prong floodplain at the benthic stations along the edge of the floodplain During previous monitoring years when fish sampling was included, the sediment was most often sampled at the location of the fyke net set which was located closer to the channel, edge sediments may have slightly different characteristics The West Prong floodplain had little to no canopy cover, however, the bank vegetation was dominated by black willow (Salix nigra) and wax myrtle (Morelia cenfera) with young bald cypress (Taxod►um distIchum) within the inundated floodplain at both Stations 1 and 2 The canopy of the two reference stations is semi -open to mostly open and the water body is much narrower Station A, the most downstream and the most natural of all the stations, has mature swamp forest trees in the floodplain and scattered black willow, wax myrtle, and swamp palmetto (Sabal minor) on the floodplain and along the stream edge Hurricane Irene in 2011 toppled many of the trees in the swamp forest, especially in the floodplain to the north and east Station A is upstream of 5 Table 1 Description of conditions at sampling stations in the Whitehurst Creek West Prong mitigation channel tenth -year (2012) aquatic macroinvertebrate survey and first -year survey at two downstream reference sites, Beaufort County, North Carolina Winter survey was conducted 22 February 2012, summer survey was conducted 25 July 2012 All measurements at all stations were taken in vicinity of bank Mitigation channel stations Reference stations Parameter Station 1 Station 2 Station A Station B Winter Summer Winter Summer Winter Summer Winter Summer Depth (in) 11 0 183 1075 125 85 1425 925 145 Canopy cover Open Open Open Open Semi -open Mostly open Semi -open Semi -open Aufwuchs Moderate Moderate Low Few Moderate Few Moderate Few Bank erosion None None None None Slight Slight None None Substrate ( %) Gravel 0 0 0 0 0 0 0 0 Sand 5 -85 10 -90 5 -10 0-45 0 0 -1 0 0 -5 Silt 5 -90 0 -35 75 -85 5 -40 75 -80 0 -4 85 5 -10 Detritus 5 -10 10 10 -15 5 -10 20 -25 30 15 25 -30 Water quality Temperature ( °C) 11 5 31 3 11 1 303 121 254 125 258 Conductivity (µS) 2526 1752 2465 2673 2483 2788 2190 2103 Salinity (ppt) 1 31 012 1 28 012 1 29 014 1 13 Oil D O (mg /L) 11 90 5 89 11 32 559 1421 373 11 11 441 pH 794 803 785 781 701 710 697 715 Water flow Low Very low Low Very low Moderate Low Moderate Low the estuarine shrub /scrub community but likely occupies the transition zone between that community and swamp forest Station B, located dust upstream of a maintained power line, is more deeply channelized than the other station Aufwuchs were noted at Station 1 and substrates consisted of predominantly silt during winter sampling and sand during summer sampling Station 2 aufwuchs were few and substrates were mostly silt during both the winter and summer sampling In comparison with the new downstream reference stations, the West Prong floodplain substrate contained slightly more sand and less detritus The higher sand percentage in the mitigation channel may reflect water level fluctuation and exposed steeper banks which occur in low water conditions after beaver removal, and the lower detritus reflects the absence of canopy Water depths were similar among the stations during each season, but the reference stations were slightly shallower than the mitigation channel stations in the winter Winter 2012 salinity levels for Stations 1 and 2 were 1 31 ppt and 1 28 ppt respectively, and summer salinity levels for both stations were 0 12 ppt Winter salinity in the reference stations was 1 29 ppt at Station A and 1 13 ppt at Station B with summer salinity 0 14 ppt at Station A and 0 11 ppt at Station B Temperatures at all stations were within 1 degree of one another in the winter sample, but as might be expected in the summer, the water was cooler by 5 degrees in the reference stations probably due to a greater degree of vegetation cover Although low in all four stations, the reference stations had slightly lower DO in the summer (3 73 — 4 41 mg /L) than the mitigation channel (5 59 - 5 89 mg /L) and DO levels in the winter were comparable among them (11 11 — 11 9 mg /L for three stations and 14 21 mg /L for Station A) The pH was close to neutral in both seasons in all stations with the highest reading found in Station 1 in the summer (8 03) and the lowest in the winter at Station A (7 01) 32 Aquatic Macroi rive rte brates A summary of aquatic macroinvertebrate taxa richness for 2012 is provided in Table 2 The summary is presented by mayor taxonomic groups, with insects divided into orders and other invertebrates divided into classes along with winter biotic indices for each station and EPT taxa richness A breakdown of macroinvertebrate taxa included within each of those groups along with relative abundances of the taxa within each season is provided in Table 3 Appendix A contains macroinvertebrate species documented in the mitigation channel from 2003 through 2012 and in the new reference stations in 2012 3 2 1 2012 Aquatic Macroinvertebrate Survey During 2012, 55 aquatic macroinvertebrate taxa, predominantly Coleopterans, Dipterans, and Odonates, were identified from the Whitehurst Creek West Prong mitigation channel and the two downstream reference stations (Table 3) Fifteen new taxa, including 12 new genera were collected in 2012 in the four stations Of the 15 new taxa, nine were new to the mitigation channel and included five new genera As in previous years since 2003, the mitigation channel itself could not be sampled due to high water, therefore, both the winter and summer 2012 7 H Table 2 Taxa richness of aquatic macroinvertebrates (by group) for the Whitehurst Creek West Prong mitigation channel tenth -year (2012) survey and first -year survey for two downstream reference stations, Beaufort County, North Carolina Winter survey (W) was conducted 22 February 2012, summer survey (S) was conducted 25 July 2012 a EPT taxa richness is a measure of the number of identified taxa within the insect orders Ephemeroptera, Plecoptera, and Tnchoptera b Biotic index only calculated for winter data as per NCDWQ recommendation Mitigation channel stations Reference stations Station 1 Station 2 Total Station A Station B Total Group mitigation Total Whitehurst Total Total channel Total Total reference Creek taxa W S station W S station taxa W S station W S station taxa taxa taxa taxa taxa Arachnida 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 Coleoptera 2 4 5 2 2 3 7 1 1 2 3 1 3 3 8 Crustacea 0 1 1 0 2 2 2 0 4 4 1 0 1 5 6 Diptera 8 5 10 6 7 11 12 4 3 6 5 1 6 9 14 Ephemeroptera 2 1 2 2 2 2 2 1 0 1 0 1 1 2 2 Hemiptera 1 2 3 1 3 4 5 0 1 1 0 2 2 2 5 Hirudinea 1 0 1 0 1 1 1 0 0 0 0 0 0 0 1 Lepidoptera 0 0 0 0 0 0 0 1 0 1 0 0 0 1 1 Mollusca 1 1 1 2 1 2 2 0 1 1 1 1 1 2 3 Nematoda 0 0 0 0 0 0 0 0 1 1 1 0 1 1 1 Odonata 1 5 5 1 3 3 7 0 0 0 1 1 1 1 7 Oligochaeta 2 1 2 2 2 4 4 0 1 1 0 0 0 1 4 Plat helminthes 1 0 1 0 0 0 1 0 0 0 0 0 0 0 1 Total taxa richness 19 20 31 16 23 32 43 7 12 18 12 8 17 28 55 EPT taxa nchnessa 2 1 2 2 2 2 2 1 0 1 0 1 1 2 2 Biotic index b 783 NA NA 854 NA NA NA 8 09 NA NA 8 13 NA NA NA NA a EPT taxa richness is a measure of the number of identified taxa within the insect orders Ephemeroptera, Plecoptera, and Tnchoptera b Biotic index only calculated for winter data as per NCDWQ recommendation 0 Table 3. Tenth -year (2012) aquatic macroinvertebrate survey of the Whitehurst Creek West Prong mitigation channel and first -year survey for two downstream reference stations, Beaufort County, North Carolina. Winter survey was conducted 22 February 2012; summer survey was conducted 25 July 2012. A dash ( -) indicates that no individuals of the taxon were documented. Highlighted rows indicate species in common with the reference stations. Taxa may include pupae, larvae, or juveniles. Taxa shown in bold have not been encountered before. A double asterisk ( "') indicates genera new to the mitigation channel. Single brackets {R, C, or A} indicates the entry was counted for the season but not for the station or year; double brackets indicate the entry was not counted at all. I Mitigation Channel j Downstream Reference Summer Coleoptera Agabus sp. R C R Berosus exiguus C - R R R Cyphon sp. { {R }} R Hydrophilidae juv.sp. R R Neoporus sp." R A - C Pellodytes spp. C C C A - C R A Tropisternus collaris R Tro isternus uadristriatus R Crustacea Apocorophium louisanum R R C R Armadlllidium vulgare" - - R R R Cambarididae juv. sp. { {R }} R Gammarus tigrinus`* R Orchestia uhleri R Ostracoda sp. R R Diotera Bezzia/Palpomyia group R R C Pilaria sp. R Chironomidae sp. { {R }} O Table 3 (continued). Mitigation Channel I Downstream Reference Station A I Station B Diotera continued Chironomus decorus group— R - C C C C Cladopelma sp. C - C - R Cladotanytarsus sp. ** C - Cricotopus sylvestns group A - A C - - Dicrotendipes sp. C Endochironomous sp. R Glyptotendipes sp. C C A R R C - Goeldichironomus carus** A R Goeldichironomus holoprasinus R - R A C Goeldichironomus sp. {R} Parachironomus sp. R R C R Paratanytersus sp. R Tanypus neopunctipennis A Tanytarsus limnecticus C Tanytarsus sp. A {C) Ephemeroptera Caenis sp. A A C R R Callibaetis sp. A C A C R Hemiotera Abedus/Belostoma sp. C C - R R Ranatra australis R Mitigation Channel I Downstream Reference Summer Hemi tera continued C { {R }} Corixidae sp. { {All _ { {All _ R Pelocoris sp. juv. R R R Trichocorixa louisianae— C C R C Trichocorixa sexcinta C Hirudinea Glossiphoniidae sp. "' Mollusca Gastropoda sp. C { {R }} Gyralus parvus R R R R R Littoridinops sp. R R Physella/Physs sp. C C R A R C Brachymesia gravida C Enallagme sp. R R A C R R Erythemis simplicicollis R Libellula sp. C Orthemis ferruginea" C N Channel Downstream Reference Station 2 Station A I Station B Winter I Summer I Winter Summer I Winter Sur Odonata continued Perithemis sp. R - C - - - Plathemis lydia C - R R 12 8 Oligochaeta Tubificidae w /hair R - R - - - Tubificidae w/o hair R - - R R 12 8 Naididae sp. f fR}} Dero sp. C R C 18 17 Pristina sp. 43 R Total taxa for 2012 all stations 55 Platvhelminthes Platyhelminthes sp. R - - - - - - Total taxa per station per season 19 20 16 23 7 12 12 8 Total taxa per station 31 32 18 17 Total taxa in mitigation channel or reference stations 43 28 Total taxa for 2012 all stations 55 NOTE: Relative abundance tabulated as rare (1 - 2 specimens), common (3 - 9 specimens), or abundant (> 10 specimens). R = rare, C = common, A = abundant collections were taken from the floodplain edge Station 1 had the greatest overall species richness during winter sampling (19 taxa compared to 16 at Station 2, 12 at Station B, and 7 at Station A) Station 2 had the greatest species richness during summer sampling (23 taxa compared to 20 at Station 1, 12 at Station A, and 8 at Station B) The EPT taxa richness was two in the West Prong and two in the reference The 2012 Biotic Index values were 7 83 and 8 54 at Stations 1 and 2, respectively, and 8 09 and 8 13 at the reference Stations A and B, respectively These indices suggest that the macroinvertebrate community composition of both the mitigation channel and the downstream reference area were dominated by tolerant species (Table 2 and Appendix A) The high proportion of tolerant species is typical of many coastal plain streams, which have been heavily impaired by channelization, sedimentation, agricultural run -off, and deforestation These low- gradient, coastal plain streams commonly also have lower flow regimes Since 2007, two genera of Ephemeroptera have been identified in both winter and summer surveys in the West Prong and one of the two Ephemeroptera species was found in each reference station Although found in the West Prong in 2008 -2010, no Trichoptera species were identified in 2012 sampling in either the West Prong or reference stations 3 2 2 Comparison of 2012 Results and New Reference Stations. The 2012 survey in the West Prong mitigation channel yielded 43 total taxa while the new downstream reference stations yielded 28 total taxa The long term average number of total taxa identified in the mitigation channel inclusive or exclusive of 2012 data is 45 (Table 4) The number of total taxa identified per station in 2012 was very similar in the two mitigation channel stations (31 and 32) and although considerably lower in total taxa, the two reference stations were also very similar to each other (17 and 18) Of the 28 taxa found in the reference stations, 17 taxa were in common with the mitigation channel or 61 percent From 2003 to 2012, the average percent in common with the 1992 baseline survey was 25 percent and the highest single year percent in common was 2007 at 34 percent While 61 percent taxa in common would seem to indicate that the new reference stations are similar to the mitigation channel, when genera across the years are compared to 2012, the Jaccard index of similarity ranges from a low of 0 09 in 2006 to a high of 0 19 in 2012 Some of the species more tolerant of estuarine conditions found in 2012 in the reference stations (e g , Apocorophlum louisanum, Gammarus tignnus, Littondrnops sp ) are evidence of the reference stations' downstream location being subject to estuarine influence These taxa have never been and are not likely to be found in the mitigation channel during the course of this study When comparing proportional distribution of taxa within the 15 groups encountered in 2012, the mitigation channel stations were more diverse for all mayor groups with the exception of Crustacea (Table 4) Until 2011, the 13 Table 4 Comparison 2012 aquatic macroinvertebrate communities for the Whitehurst Creek West Prong mitigation channel tenth -year (2012) surveys and first year (2012) for two downstream reference stations, Beaufort County, North Carolina 2012 survey results by number of taxa within major taxonomic groups 14 2012 West Group Prong 2012 reference 2012 Whitehurst mitigation stations (n =2) Creek all stations channel (n =2) Arachnida 0 1 1 Coleoptera 7 3 8 Crustacea 2 5 6 Diptera 12 9 14 Ephemeroptera 2 2 2 Hemiptera 5 2 5 Hirudinea 1 0 1 Lepidoptera 0 1 1 Megaloptera 0 0 0 Mollusca 2 2 3 Nematoda 0 1 1 Odonata 7 1 7 Oligochaeta 4 1 4 Orthoptera 0 0 0 Plat helminthes 1 0 1 Total richness 43 28 55 EPT 2 2 2 Jaccard index 019 of similarity Taxa in common with 17(61%) reference 14 Jaccard index of similarity was calculated in previous reports based on species similarity with the 1992 baseline, however, the methodology for calculation of this index in Section 2 2 indicates this index should have been calculated using genera similarity For this report, genera have been used and the Jaccard indices in Appendix A have also been re- calculated for all years compared to the 2012 reference stations The Jaccard index of similarity for 2012 samples (0 19) suggests that the communities in the two sampling areas (mitigation channel and reference) were not very similar although the index has generally gotten higher across the years of monitoring (Appendix A) Colonization dynamics of benthic macro i nve rteb rates are very complex, varying with habitat, life- histories, source populations, and season, among other factors Invertebrates re- colonize streams by four primary mechanisms downstream drift, upstream migration, vertical migration from the hyporheic zone, and aerial deposition (Williams and Hynes 1976, Smock 1996) Vertical migration is unlikely to be important due to the age and history of the mitigation channel Downstream drift is also unlikely to be an important source of new species because the West Prong mitigation channel is located in what is both currently and historically the approximate upstream end of Whitehurst Creek. Therefore, upstream migration and aerial deposition are the most probable sources of colonizers This may occur in part due to the shift in surrounding landscape vegetation from agricultural fields and hedgerows present during the baseline survey to current planted reclamation areas Differences in species composition may also be related to differences in sampling location and in- stream habitat, the patchy distribution of macro i nverte b rates, variations in adjacent habitats that may attract a different suite of adult insects, and /or temporal patterns of community succession Also, changes in upland habitat near the streams might influence the addition or loss of some species Researchers have found that species composition is influenced by location within the stream- floodplain complex, such that the presence or absence of certain species will reflect sampling location (Benke 2001, Smock 1988) Thus invertebrate species, particularly those with highly specific habitat preferences, may not be documented if their favored habitat is excluded from sampling Particle size of substrate is one of the most important determinants of macroinvertebrate community characteristics (Townsend et al 1997, Zweig and Rabeni 2001) in large part determining food resources, reproductive habitat, and dissolved oxygen levels Finally, hydrology could explain some species differences between the mitigation channel and the downstream references stations, because the mitigation channel is almost never confined to its true channel and its floodplain is most commonly submerged Even when samples are taken from similar habitats, sample variability is often high due to the naturally patchy distribution of aquatic invertebrates (Brooks et al 2002) Small scale patchiness is a normal feature of 15 invertebrate communities and results from abiotic factors and biotic interactions such as competition and predation 4 0 SUMMARY Forty -three (43) taxa from 10 groups of aquatic macro i nve rteb rates were recorded in the 2012 survey of the Whitehurst Creek West Prong mitigation channel and 28 taxa from 11 groups were recorded from the reference stations in downstream Whitehurst Creek In the 2012 survey seven new genera, two of which had taxa identified to the species level, four new species, and one new group was identified This brings the total taxa collected from 2003 to 2012 to 156 Biotic Index values reflect similar conditions across the four stations and the macroinvertebrate orders collected in 2012 represent environmentally tolerant predators and collector - gatherers Successional status, complex life histories, and inherent patchiness of invertebrate communities may also account for some differences Appendix B contains selected photographs taken during the 2012 surveys 16 REFERENCES Benke, A C 2001 Importance of flood regime to invertebrate habitat in an unregulated river- floodplain ecosystem Journal of the North American Benthological Society 20 (2) 225 -240 Brigham, A R , W U Brigham, and A Gnilka, eds 1982 Aquatic insects and oligochaetes of North and South Carolina Midwest Aquatic Enterprises, Mahomet, Illinois 837 pp Brooks, S A, M A Palmer, B J Cardinale, C M Swan, and S Ribblet 2002 Assessing stream ecosystem rehabilitation limitations of community structure data Restoration Ecolocgy 10 156 -168 Brower, J E and J H Zar 1984 Field and laboratory methods for general ecology Macgraw -Hill 288 pgs. CZR Incorporated 1993a Whitehurst Creek water quality and sediment sampling 1992 baseline Wilmington, North Carolina CZR Incorporated 1993b Upper Whitehurst Creek aquatic macroinvertebrate and fish survey 1992 baseline report Wilmington, North Carolina CZR Incorporated 1994 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1993 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 1995 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1994 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 1996 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1995 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 1997 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1996 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 1998 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1997 Mitigation Channel Report Wilmington, North Carolina 17 CZR Incorporated 1999 Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1998 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2000a Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 1999 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2000b Upper Whitehurst Creek aquatic macroinvertebrate and fish survey and water quality analyses 2000 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2004 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2003 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2005 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2004 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2006 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2005 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2007 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2006 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated. 2008 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2007 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2009. Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2008 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2010 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2009 Mitigation Channel Report Wilmington, North Carolina CZR Incorporated 2011 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2010 Mitigation Channel Report Wilmington, North Carolina 18 CZR Incorporated 2012 Whitehurst Creek West Prong aquatic macroinvertebrate and fish survey and water quality analyses 2011 Mitigation Channel Report Wilmington, North Carolina NCDENR 2001a Standard operating procedures for benthic macroi rive rte brates, Biological Assessment Unit Division of Water Quality, Water Quality Section Environmental Sciences Branch NCDENR 2006a Standard operating procedures for benthic macroi nverte b rates Biological Assessment Unit Division of Water Quality, Environmental Sciences Section Smock, L A 1988 Life histories, abundance and distribution of some macro i nverte brates from a South Carolina, USA coastal plain stream Hydrobiologia 157 193 -208 Smock, L A 1996 Macroinvertebrate movements drift, colonization, and emergence Pages 371 -390 in Methods In Stream Ecology F R Hauer and G A Lamberti, eds Academic Press Townsend, C R, M R Scarsbrook, and S Doledec 1997 The intermediate disturbance hypothesis, refugia, and biodiversity in streams Limnology and Oceanography 42(5) 938 -949 Williams, D D and H B N Hynes 1976 The recolonization mechanisms of stream benthos Oikos 27 265 -272 Zweig, L D and C F Rabeni 2001 Biomonitoring for deposited sediment using benthic invertebrates a test on 4 Missouri streams Journal of the North American Benthological Society 20(4) 643 -657 19 APPENDIX A AQUATIC MACROINVERTEBRATE TAXA DOCUMENTED IN UPPER WHITEHURST CREEK DURING THE 1992 BASELINE AND IN THE WHITEHURST CREEK WEST PRONG MITIGATION CHANNEL DURING 2003 THROUGH 2012 SURVEYS AND IN DOWNSTREAM REFERENCE STATIONS IN 2012 Appendix A. Aquatic macroinvertebrate species documented from the Whitehurst Creek West Prong mitigation channel winter and summer 2003 through 2012, and two new downstream reference stations for winter and summer 2012. The list has been rearranged taxonomically using using ITIS, Discover Life, and Wikipedia. Purple = reference taxa. *taxa = 2012 reference channel taxa; taxa ** = new to mitigation channel: bold = new taxa; { } = count for season not for year; {{ }} = not count for season or year Group Taxa 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 1st year 2nd year 3rd ear 4th year 5th year 6th Vear 7th Vear 8th year 9th Vear 10th year Reference W S W I S W S W S W S W S W S W S W s W S W S Crustacea r,*Apod&ophium louisanum Armadillidium quadrifrons - -- - - -- T X X - ! - X _ - -_ X * vulgar e" vuI g " - *Cambaridae sp. _ - - - -- Procambarus - X X - -T- t - _- X {X} I X X - .P' - Gammarus trgrinus Harpacticoida sp. - -- hestla ulherii - - - - Ostracoda sp. Simocephalus exspinosus - - -- X �- -- - li - -- - - -- I X - X _ rt - -- X - -- - X _- - X - -- -- X - - -- X X - - -� X ;_ T X - t- X X X+ X - X - Mollusca - - Fossaria cubensis Fossaria sp. X X X X- 1 -- X X - - -- X X -- - -- - -- {{X}} - -- t -- X - - -- - X r- -- {X} - X Gyraulus sp. - Gyraulus parvus *Liftridinops sp. *Ph . sa s sell h Pseudoscuccinea collumella - --� -- X X X X X �- I X I X _ ` X X --�- -_ X X X X X X X - -_� X X � X X X X X X - _ X X X Oligochaeta Naididae sp. ; -- _ � T- � � { {X }} - � { {X }} I - Chaetogaster sp. X X X X X X X X Dero sp. X -- X X _ X- X - X X X_ X � x X X X X X Nais sp. - - ! _ T Pristina sp. -- � - X_ X X X X _ X X - - - + -- X - -- - -- T �, ! -- �- X � X -- _ X �_ X - Tubificidae w/ hair * Tubificidae w/o hair *Caenis sp *Callibaetis Anomalagrion hastatum Maxim us Ephemeroptera Odonata _ X X -; X Y- - - -! - - X - ', - -- -_ X ', X X X X X #Xx X X X X ; X X X r- X X X X- X; X X� X X X X X - -- X X - - - -- - - - - - _, r— -,- - - -- - - -- - - -- i -X - - - -I T _ -- X X _� __ X - - - - -- {X }- - - { {X}} - - -- - -- X X - - - -� X -X -- -. i - -� - _ X �- - -- _ - - -- - - - -- *En al/agma sp Ischnura posda --- --- - - -- -- — - - - - -- Ischnura/Anomalagrion sp. Ischnura sp. - - -- - -- X X_ X X - - ! X X X X - - -- - X _X X X X - fi - - -- - — X - - - -r - -- r - -- -- - - -- X - -- � - -- - -� - -- - ! - - -- ---- - - - - -- X X - -L--- r - -X — X - - -- -- - - - -r -- ; - - - - - -- - -- Libellulidae sp. - I { {X }} {X} i {X }} - - Brachymesia gravida Erythemis simplicicollis - -- - Erythrodiplax Berenice Erythrodiplax connata subsp. miniscula Libellula luctuosa Libellula sp. Nannothemis befia Orthemis ferruginea** - -r -- I - - X X X -- ' X -X _ X I - -__ - -- L -- X_ X - X X - X X - - �- - - - - -- X ---- -t - - - -- X X- X X r - -- - X - - -r - -- _X _X rt X X X � X - - -- I_- _ X - -- { {X }} {X} -- _ _ _ X X - X - - - - -I - -- _ X -; -X X - - -! -- - - - - - -- - -r- -- - X -- - - - - -- Pachydiplax longipennis Perithemis sp. X X X ;-- X -` -- 1 -- -- - -�- _ X X 1 X X X Plathemis Lydia Sympetrum (ambiguum) X X Appendix A -1 Annendix A. (continued) Group Taxa 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 1st year 2nd year 3rd year 4th year 5th year 6th year 7th year 8th year 9th year 10th year Reference W s W s W s W s W s W s W s W s W s W s W s Odonata continued Sympetrum obtrusum —� _ _ X Sympetrum rubicundulum _ X Tramea (carolina) -:--E X Progomphus sp. X Hemiptera 'AbedusMelostoma sp. { {X }} - X { {X }} X X X 1 { {X }} X X Belostoma flumineum - - X -- -- - X X Belostoma lutarium - - X Belostoma sp. - - j X X -- Belostoma testaceum - � X { {X }} + { {X}} X {X} X X X {X} X Trichocorixa kanza Tdchocorixa louisianae *' _ X Trichocorixa sexcinta j 1 X X X_ r - X Trepobates subnitidus X Merragata sp. X Mesovelia mulsanti - -- - -_ -_ - X X Mesovelia sp. - - I _ _ � X _ Notonecta raleighi X Pelocris carolinensis X I Pelocoris femoratus X X X X X X X X Pelocoris sp. X { {X}} { {X }} { {X }} { {X }} {X} { {X }} { {X }} X Ranatra australis X X X X X X X Ranatra bueoni X — - - - -- Ranatra nigra -; - X Ranatra sp. { {X }} Microvelia americana X Paravelia brachialis X _ Rhagovelia obesa X Coleoptera Agabetes acuductus X Agabetes sp. X — Berosus sp. X — X X 1_ _ Berosus exiguus X _ X X Berosus infuscatus - -- Celina sp. X -- Copelatus princeps X Copelatus sp. - Cybister (fimbriolatus crotchi) sp. X _ - -- Cybister sp. X X X - *dyphon'sp,° ' Deronectes grisseostriatus X X X X X Dineutus assimilis _ _ X Dytiscidae sp. X X X X X X Agabus sp. Dytiscus fasciventris - Hydaticus sp. - - - - - — X - - -� X - t - - _ — Hydroporus (clypealis) X Appendix A -2 AnnonrliY A (cnntinuraril Group Taxa 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 1st year 2nd year 3rd year 4th 5th year 6th year 7th year 8th year 9th year 10th year Reference w S w S w S w w s w S w S w S w S w s w S Coleoptera continued Hydroporus oblitus X X X X Hydroporus sp. �' X X - Hydrovatus pustulatus subsp. compressus X X llybius biguttalus -T- llybius sp. X X X Halip/us fasciatus X _ Halip/us tnopsis X X - Halip/us sp. I X {X} { {X }} X _ Hoperius planatus _ i X X - Hydrobius sp. -- X _ Hydrocanthus sp. I � X -- _ Hydrophilidae sp. _ X _ - X Enochrus hamiltoni X Enochrus (interruptus) X Laccophilus fasciatus rufus X _ Macronychus glabratus -- X _ - Mclanotus sp. X *N _s .sW* - I X X -. _ _ -_ Notomicrus nanulus -� X X Peltodytes dietrichi X X Peltodytes lengi X X X X X X _ 1 X X X Peltodytes oppositus X _ X X X X X X X X Peltodytes sexmaculatus Peltodytes shermam. *Peltodytes sp. X _ - X ._ _- _ _ _ X X X X X X { {X }} { {X }} { {X }} _ Rhantus calidus Scirtes sp. X Suphicellus bicolor punctipennis X X X Thermonectes basillaris basillaris X Tropistemus collaris X X X X X X Tropistemus lateralis nimbatus X X X Tropistemus quadristriatus quadristriatus _ X X Tropistemus sp. X { {X}} Uvarus lacustris X X - -- Diptera C/O (sp. 1) - - X — C/O (sp. 5) X X _- C/O (sp. 9) _ -�- C/O (sp. 41) Ablabesmyia sp. _ Anopheles walkeri X X X X X _ X Appendix A -3 Annenrlix A_ Icontinuedl Group Taxa 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 1st ear 2nd year 3rd year 4th year 5th year 6th year 7th year 8th year 9th year 10th year Reference W S W S W S W S W S W S W S W S W S W S W S Diptera continued Anopheles (quadrimaculatus) X X X _ X - Asheum sp. _ Bezzia/Palpomyia group X X X X X X X X X Chaoborus punctipennis Chironomidae sp. X (X }} { {X }} *Chironomus decorus ''ro` ** u - X X X - - Chironomus stigmaterus X X T Chironomus sp. X X {X} { {X }} {X} { {X }} X X X X X X X X X X - - *Cladope/ma sp: Cladotanytarsus sp. ** X X X X - -- - - Clinotanypus sp. X X X WX-- j Cryptochironomus sp. Dicrotendipes modestus X #—I X Dicrotendipes nervosus X _ X Dicrotendipes simpsoni otendipes sp. Endochironomous sp. *Glyptotendipes sp. X { {X }} I _ _ X X X X X { {X}} X X X X X X X X- Glyptotendipes testaceus X X Goeldichironomus carus** _ X Goeldichironomus devineyae "Goeldichironomus holopra s *Goeldichironomus s . , X 1 X X -' X X -+ X X X- - X X X X X { {X }} _ - -- { {X }} - - T _ - - - -- -- -- - {X} j - - Larsia sp. Microspectra sp. Parachironomus hirtalatus X X X X X X X X X -- X - - X - X X *Paratanytersus sp. - - Polypedilum sp. X X X X X X X X X X T - - - - -- X _X X Procladius sp. X X Rheotanytarsus sp. 1 X X X - - -- -- - - Tanypus carinatus �- X X X- - { Tanypus neopunctipennis Tanypus punctipennis X X X X X X X X X X X X X X X X X _ X X X Tanytarsus limnecticus X; Tanytarsus sp. {X} X { {X }} X X {X} - - - _ - - - -- - Tanytarsus (sp 1) X X X _ - - -- Tanytarsus (sp 10) X- X -- Zavreliel_la sp. _ X X _ _ X Orthocladinae sp. { {X }} _ Corynoneura sp. C *Cnootopus sylvestris group X - X - _ _ X X Cricotopus sp. Psectr_ocladius vernalis Zalutschia sp. _ _ - X - - X Appendix A -4 div A_ (rnnrludedl Group Taxa 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 1st year 2nd year 3rd year 4th year 5th year 6th year 7th year 8th year 9th year 10th year Reference W S W S W S W S W S W S W S W S W S W S W S Diptera continued Trichoptera Arachnida Hirudinea Lepidoptera Megaloptera Nemertea Nematoda Platyhelminthes Chrysops sp. Culex restuans Dasyhela sp Diptera sp. Odontomyia sp. X X -- - . X X X X - X X X X I X X { {X }} { {X }} X X _ - X X - - -- { {X }} - X X X X X X X- - { {X }} { {X }} X X - _ X X — X X { {X }} X X - _ *Pilaria sp. - — Stratiomys sp. Tabanus sp. Oecetis cinerascens Oecetis inconspicua - -- Oecetis sp. Oecetis spp. Thysanura sp. Arachnida sp. X - - - — *Tetragnatha sp. Hydracarina sp. Branchiobdella sp. Glossiphoniidae sp. Helobdella sp. Lepidoptera sp. X _ X X X X *Pyralidae sp. Chauliodes pectinicornis _ Prostoma graecense * Nematoda sp. IPlatyhelminthes sp. X - X X X X Total taxa per season 29 31 19 24 23 15 21 22 28 43 31 41 16 29 23 37 31 36 23 32 18 17 Total taxa per year 49 34 31 39 55 59 39 50 53 43 28 Number of taxa in common with new reference stations 8 9 8 6 11 10 11 10 15 17 Jaccard index a (genera compared to 2012 reference 0.11 0 -15 0.14 0.09 0.13 0.14 0.16 0.10 0.17 0.19 N/A Jaccard index a (species compared to 2012 reference 0.12 0.17 0.16 0.10 0.15 0.13 0.20 0.15 0.23 0.31 N/A Total taxa in mitigation channel 2003 -2012a 156 Note: Taxa identified only to genus are not counted in totals when the same genus is represented to species during the season or year (per NCDWQ enumeration standards, indicated by { {X } }. Some taxa are counted for the season but not for the year and are indicated by {X }. When counting genera by year or season or when counting genera in common, brackets do not always apply as when counting taxa. a Total taxa and the Jaccard index values differ from previous year reports due to re- evaluation of when taxa identified to family are counted (i.e., when no other taxa within the family are found /counted) and not counted (when taxa within the family are found /counted) as a taxa in common to reference. Taxa in common refers to genera (or family, when appropriate, as described in Note above) found during monitoring years in comparison with those collected in the reference stations in winter 2012. Appendix A -5 APPENDIX B SELECTED PHOTOGRAPHS FROM 2012 SURVEYS IN WEST PRONG MITIGATION CHANNEL AND TWO NEW REFERENCE SITES DOWNSTREAM Site1. Upstream view of Whitehurst Creek West Prong Mitigation Channel, collection of water quality data, 22 February 2012. Site 1. Upstream view of Whitehurst Creek West Prong Mitigation Channel, 25 July 2012. 95 Site 2. Upstream view of Whitehurst Creek West Prong Mitigation Channel, collection of water quality data, 22 February 2012. Site 2. Upstream view of Whitehurst Creek West Prong Mitigation Channel, 25 July 2012. M Site Ref A. Upstream view of Whitehurst Creek, collection of water quality data, 22 February 2012. Site Ref A. Upstream view of Whitehurst Creek, 25 July 2012. AN Site Ref B. Upstream view of Whitehurst Creek, collection of water quality data, 22 February 2012. Site Ref B. Upstream view of Whitehurst Creek, sweep sampling, 25 July 2012 LQ ,i