PEMY NE PAMDS Covet, te 112 Monitoring Cruise at the Boston Lighthouse Disposal Site, August 1994 Disposal Area Monitoring System DAMOS Ta ea DISPOSAL AREA MONITORING SYSTEM Contribution 113 August 1996 US Army Corps of Engineers ___ New England Division Ge | [SF | Derg | no. HZ Form approved REPORT DOCUMENTATION PAGE Public reporting concern for the collection of information is estimated to average | hour per persons inculding the time for reviewing instructions, searching exsisting data sources, gathering, and measuring data needed and correcting and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collectikon of information includin suggestions for redueiie this burden to Washington Headquaters Services, Directoriate for Information Observations and Records, Pas Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302 and to the Office of Management and Support. 1. AGENCY USE ONLY (LEAVE BLANK) 2. REPORT DATE 3. REPORT TYPE AND DATES August 1996 Final Report 4. TITLE AND SUBTITLE MONITORING CRUISE AT THE BOSTON LIGHTSHIP DISPOSAL SITE, AUGUST 1994 6. AUTHORS Ed DeAngelo 7. PERFROMING ORGANIZATION NAME(S) AND ADDRESS(ES) i8. PERFORMING 6. FUNDING NUMBERS Science Applications Intenational Corporation ORGANIZATION REPORT 221 Thrid Street Newport, RI 02840 SAIC No. 328 9. SPONSORING/MONITORING AGENCY NAMES(S) AND ADDRESS(ES) US Anny Corps of Engineers-New England Division 424 Trapelo Road Waltham, MA 02254-9149 10. SPONSORING/ MONITORING AGENCY DAMOS Contribution Number 113 11, SUPPLEMENTARY NOTES Avaiable trom : 424 Trapelo Road Waltham, MA 02254-9149 12a. DISTRIBUTION/AVAIABILTY STATEMENT 12b. DISTRIBUTION CODE Approved for public release; distribution unlimited 13. ABSTRACT Science Applications International Corporation (SAIC) conducted a reconnaissance REMOTS® sediment- profile and plan view photographic survey of the Boston Lightship Disposal Site (BLDS) from 9 to 11 August 1994. From the 1940’s to 1976, when disposal stopped at BLDS, a majority of the Boston area’s dredged material and other debris had been released at this site. The last recorded disposal at this site was in 1976 when about 8,000m3 were disposed. The REMOTS® sediment-profile and plan view photographic stations were located to examine possible historic dredged material that had been identified in a 1991 side-scan sonar survey of the area. The 1994 surveys were conducted as part of a long-term effort to examine historical disposal areas to determine whether remediation activity is recommended. The assessment of the REMOTS® and plan view data, in conjunction with the 1991 side-scan results, determined that remediation at the site was not necessary. Recolonization of old dredged material has been extensive. The benthos in the areas sampled was populated by a diverse community composed of Stage II and Stage III organisms representing a healthy benthic habitat with OSI values *6. No difference was observed between the historic dredged material and the ambient sediment. In light of the healthy benthic habitat, only periodic monitoring is recommended. Sediment samples were collected at BLDS in 1994. They were archived and are available for analysis. The REMOTS® sediment-profile and plan view photographic surveys were also conducted to gather information on the area's sedimentary environment. This information would determine if the BLDS was suitable to potentially receive dredged material from the Boston Harbor Navigation Improvement Project and Berth Dredging Project. The 1991 side-scan sonar survey had mapped areas of circular or track-like dredged material patterns at the site. The use of the area for dredged material disposal was consistent with its characterization as depositional or nonerosive (Knebel 1993). By focusing on the areas of dredged material disposal with the REMOTS® sediment-profile and plan view photographic survey, the reconnaissance effort produced no evidence to preclude the future use of BLDS for dredged material disposal. The major modal grain size was the silt/clay size class (>4 phi) with very fine sands found in the surface sediments. Evidence of sediment resuspension was limited primarily to winnowing of silts/clays from surface sediments. The assessment of BLDS was efficiently accomplished by basing the REMOTS® sediment-profile and plan view photographic survey on the results of the previous side-scan survey. The combined data sources provided a broad picture of the status of the historical dredged material which has been at the disposal site for more than 20 years. Based on the 1994 survey results, remediation is not necessary for BLDS, and the depositional environment does not preclude its use as a disposal area. 14. SUBECT TERMS . : : : : : 15.NUMBER OF PAGES Boston Lightship Disposal Site (BLDS) , Boston Harbor Improvement Project , benthic habitat, Remote Monitoring of the Seafloor (REMOTS) , dredged material, nonerosive or depositional 16. PRICE CODE 17. SECURITY CLASSIFICATION OF REPORT | 18. SECURITY CLASSIFICATION 19. SECURITY CLASSIFICATION — 20.LIMITATION OF UNCLASSIFIED OF THIS PAGE OF ABSTRACT ABSTRACT 6 VeVi gee Tr la DNs utter tay yy, Ati if ai i i atid MONITORING CRUISE AT THE BOSTON LIGHTHOUSE DISPOSAL SITE AUGUST 1994 CONTRIBUTION #113 August 1996 Report No. SAIC No. 328 Submitted to: Regulatory Division New England Division U.S. Army Corps of Engineers 424 Trapelo Road Waltham, MA 02254-9149 Prepared by: Ed DeAngelo Submitted by: Science Applications International Corporation Admiral's Gate 221 Third Street Newport, RI 02840 (401) 847-4210 US Army Corps of Engineers New England Division PRO terion z teh aa fea g. SANTO ees el a MONITORING CRUISE AT THE HISTORIC BOSTON LIGHTSHIP DISPOSAL SITE AUGUST 1994 24 July 1996 Contract No. DACW33-93-D-0002 Work Order 21, Task 2 SAIC Report No. 328 Submitted to: New England Division US Army Corps of Engineers 424 Trapelo Road Waltham, MA 02254-9149 Prepared by: Ed DeAngelo Submitted by: Science Applications International Corporation Admiral's Gate 221 Third Street Newport, RI 02840 (401) 847-4210 De TABLE OF CONTENTS Page LASSE LO} cM Be 24 1S) SI Rn or er ea Nee nea iain in niele ROM Me aan MOT ar Ca ON id OAR Le Se ill TES MO BIRIG WIRES seers a ics alot carcuee teeretirterS cs ote ten rita yer tote a RP ee iv Fea CU TGTINIE SS WIV IRE ins oreo wrest Sc clo Grverte ees ia ocean cede ge me Vi OPN RO DW GTO § ceciacot cad seeee cena arse ater care ene salts seat San ncaa Oe aN eR ee a 1 AOR VAST OD) Sis a0 or eee retina dal iesssstacas acta cea a farty ase ance a ee en van 5 2.1 REMOTS® Sediment-Profile and Plan View Photography ...............0..0.0ec0eeeee 5 DO SCGUMENU SALT IIM Oto rac sg anaes oe aateeoild MASA aS RE Oe RCE aE ee Te ee 5 PO WINAN IS ALL OM tice ie satis Petes Hcciome a ene Tee ye iatecice Vn Rea ns TRH eR 8 She(0) LRLGIS UI] bal CS esa se rotor Ie ace te irene SUM Mee eR A EA ahs te 9 SeUREMOTS='Sediment-Profile Photography, .3.¢.2.-.0...-.-.520- ee eee 9 SalmioPresence:of Dredged*Matenialie gece ca natenn at eene ete. toe ate ener 9 Srl eZ i Gran Sizes DIS (IDUL OM seen oe ec eeies eee eos eee ree 9 3.1.3 Apparent Redox Potential Discontinuity (RPD) Depth.......................... 9 Sled SUECESSIONAlT Stage en ee ceae ta sue re neat meee tc neers aaa ak ee 14 Salo Oreanism-Sediment IMdex eaweaaseeeum neces eens see asa ee yen ee 14 Seca lan VIE Ws NOLO Staph yrs. screen see avec etoae ce ae eae ok Sasa enna oe ntals ee ane 14 ARUP TS @USSIOIN 25 i200 0s alae, ge NU aii tet cater Scuniaat seit sina iyczta ct UO nO na ctaatan DEE 24 4eleihe Sedimentary EnvironmentOr BEDS ies. .cso yee ee sean eee 24 Ae) spresence Om Dredgeds Material awn ueasncnnaessasen casero nes ne een ee ee 26 AS ABenthiCyRECOlOMIZANMOMS sssacn. cece cans ce sce aca ee Toren eae ec eel one Eee ene ID SR OREONGIEW SION Bee cuut aaa Seb uct wa tne Sete eaters re Mcrtutte emer crag a ears trerti a ee eP 29 ORO PRE BEIRIEIN © ES age 22a sti ne ten diesen Nee h ae deen enna eater eae Ro ac ater RT om Mare ota 30 INDEX APPENDIX oy a Nitin oar vive ee ‘ Ae aa Siena SUS trots eT in if Table 2-1. LIST OF TABLES Station Target Locations for REMOTS® Sampling at BLDS Ul a ‘ a Figure 1-1. Figure 1-2. Figure 2-1. Figure 3-1. Figure 3-2. Figure 3-3. Figure 3-4. Figure 3-5. Figure 3-6. Figure 3-7. Figure 3-8. Figure 3-9. Figure 3-10. Figure 3-11. LIST OF FIGURES Page Site location map of the Boston Lightship Disposal Site ........................ 2 The relative locations of dredged material located by side-scan sonar; 1994 REMOTS® sampling transects; a depositional sedimentary environment above the 50 m depth contour; and asproposed ‘disposallocationic. ewene-ccae-ceen ce ene eee ects nie aes eee 4 REMOTS® samphingttransects hectare tsa eee eee ee 6 The number of stations per transect where dredged material was observed in-the/REMOTS® images eine arse lated ee eee 10 Light gray, high reflectance Boston Blue Clay located at Stations C3=10i(A)randiC227.\(B) aeseen eee acces ge eda Sicuy hansen 11 Layer of biogenically reworked sediments over dredged material and large Stage III polychaete feeding in the dredged material layer......... 12 Transect average apparent redox potential discontinuity depths (cm) ........ 13 Example of a thick RPD (4 cm) observed at Station C3-1..................... 15 Surface sediments at BLDS colonized by Stage II "stick-building" amphipods (Family Podocerdiae; A) and Stagealll tube-dwelling polychaetes (B) ie... 2. ye eeteene tee renceeet onan ene 16 Water-filled feeding void below the RPD at Station C6-4 ..................... 17 Bioturbating caudate holothurian Molpadia oolitica at Station C2-10........ 18 Transect average Organism-Sediment Index values ...................eeeeeee eee 19 Summary of bottom features observed in plan view photographs............. 20 Possible construction debris—large, sharp-angled, silt-covered rocks observed in plan view photographs from transects Cl (A) TNC ACB) eee Sa SALT oak rene Ce ree et ne a es err UM tea ar Tae 22 Iv LIST OF FIGURES (continued) Figure 3-12. Heterogeneous distribution of surface polychaete tubes ranging froma dense\carpet (A):to nearly absent (B) 2220. one oie ses teenct ssc s oneal 23 Figure 4-1. Location of depositional environments in Massachusetts Bay from the shore*to the 50 my depth: Comtour . i272. eset cecenss dae cee see oe eee eeeee 25 EXECUTIVE SUMMARY Science Applications International Corporation (SAIC) conducted a reconnaissance REMOTS® sediment-profile and plan view photographic survey of the Boston Lightship Disposal Site (BLDS) from 9 to 11 August 1994. From the 1940s to 1976, when disposal stopped at BLDS, a majority of the Boston area's dredged material and other debris had been released at the site. The last recorded disposal at the site was in 1976 when about 8,000 m° were disposed. The REMOTS® sediment-profile and plan view photographic stations were located to examine possible historic dredged material that had been identified in a 1991 side-scan sonar survey of the area. The 1994 surveys were conducted as part of a long-term effort to examine historical disposal areas to determine whether remediation activity is recommended. The assessment of the REMOTS® and plan view data, in conjunction with the 1991 side-scan results, determined that remediation at the site was not necessary. Recolonization of old dredged material has been extensive. The benthos in the areas sampled was populated by a diverse community composed of Stage II and Stage III organisms representing a healthy benthic habitat with OSI values 26. No difference was observed between the historic dredged material and the ambient sediment. In light of the healthy benthic habitat, only periodic monitoring is recommended. Sediment samples were collected at BLDS in 1994. They were archived and are available for analysis. The REMOTS® sediment-profile and plan view photographic surveys were also conducted to gather information on the area's sedimentary environment. This information would determine if the BLDS was suitable to potentially receive dredged material from the Boston Harbor Navigation Improvement Project and Berth Dredging Project. The 1991 side-scan sonar survey had mapped areas of circular or track-like dredged material patterns at the site. The use of the area for dredged material disposal was consistent with its characterization as depositional or nonerosive (Knebel 1993). By focusing on the areas of dredged material disposal with the REMOTS® sediment-profile and plan view photographic survey, the reconnaissance effort produced no evidence to preclude the future use of BLDS for dredged material disposal. The major modal grain size was the silt/clay size class (>4 phi) with very fine sands found in the surface sediments. Evidence of sediment resuspension was limited primarily to winnowing of silts/clays from surface sediments. The assessment of BLDS was efficiently accomplished by basing the REMOTS® sediment-profile and plan view photographic survey on the results of the previous side-scan survey. The combined data sources provided a broad picture of the status of the historical dredged material which has been at the disposal site for nearly 20 years. Based on the 1994 survey results, remediation is not necessary for BLDS, and the depositional environment does not preclude its use as a disposal area. VI At ata bari i) A a h (hae ives Bly ts ere eu Sass Tae A earl LON lent te | 1.0 INTRODUCTION The consideration of BLDS as an alternative site for future disposal operations (Normandeau Associates 1994) and the existence of an extensive data set on observed dredged material at the site (Schoenherr et al. 1992) provided impetus for the study described here. A reconnaissance survey of the Boston Lightship Disposal Site (BLDS), a currently inactive site located 16 nmi east of Boston (Figure 1-1), was conducted under the Disposal Area Monitoring System (DAMOS) Program as part of a long-term effort to investigate historical disposal areas. From the 1940s to 1976, when disposal stopped at BLDS, a majority of the Boston area's dredged material and other debris had been released at the site. During the late 1960s and early 1970s, BLDS received approximately 2.3 million m° of material dredged from Boston Harbor (Normandeau Associates 1994). Disposal at the site was directed toward the Dumping Ground (DG) buoy. However, the buoy location only served as a general guide for the barges and was not used for point dumping. Although disposal activity was concentrated in an area surrounding the buoy, material was apparently disposed throughout the site. Prior to the early 1970s, the oversight of the nature and placement of disposed materials was less stringent than at present. The US Army Corps of Engineers, New England Division (NED), has initiated a cooperative effort to investigate historical disposal sites, whenever possible, to determine existing environmental conditions. One potential remediative activity might be to use present disposal activities to cover old deposits. Science Applications International Corporation (SAIC) conducted short (9-11 August 1994) REMOTS® sediment-profile and plan view photographic surveys of small areas within the disposal area. These areas were deemed likely to contain dredged material based on a previous side-scan survey. The primary objective of the survey was to explore the need for dredged material remediation. The relative health of the benthic environment was determined by the recolonization status of relic dredged material compared to results obtained from ambient sediment. The secondary objective was to determine if there was any evidence to preclude future use of the site for dredged material disposal. Small scale sediment characteristics in the REMOTS® and plan view photographs, in conjunction with features identified in the side-scan records, were examined to determine if the sedimentary environment was suitable for future dredged material disposal. Until recently, little was known regarding the location and nature of the material that had been disposed at BLDS. In 1991, the US Environmental Protection Agency (EPA) sponsored a side-scan and Remotely Operated Vehicle (ROV) survey of BLDS. SAIC supported efforts to locate, identify, and determine the condition of waste containers in the area (Schoenherr et al. 1992). Interpretation of the side-scan records over a 16 nmi- Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 GLOUCESTER ry, MANCHESTER oy «shore Station 2 [Shore Station NG ‘3 42°30' N MARBLEHEAD | \@2> | we | | x Bris ecan \ TO Interim BOSTON | Survey meps 7<( MBDS | \ "18-17 : | REF | FG23 REF e | i] | SE REF e aX | .___ Boston Lightship —— od Disposal Site “ade > aN SY Massachusetts Bay eee \ = | B & ~ 1 Pe scvTer Ma 0) nmi 5 0 4 8 12 km Figure 1-1. Site location map of the Boston Lightship Disposal Site. The Boston Lightship Disposal Site is located approximately 16 nmi east of Boston, MA. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 area (Figure 1-2) located 469 dredged material targets in addition to 43 potential waste barrel fields, and 136 debris fields. Dredged material targets generally appeared on the side-scan records as circular or track-like patterns of sediment with a marked contrast to the surrounding natural sediments. While the dredged material targets were scattered throughout the disposal area, high concentrations were located in a ring around the former DG buoy location and to the south of the buoy beyond the 50 m depth contour. In the 1994 reconnaissance survey, the REMOTS® and plan view photography station locations corresponded to areas of dense dredged material targets. This sampling scheme supported the primary objective of the survey by maximizing the probability of collecting data from relic dredged material where the potential need for remediation would be the greatest. A secondary objective of the present survey was to characterize the dominant processes controlling the sedimentary environment and to determine the suitability of the area for potential future disposal. The area greater than 50 m depth at BLDS has been suggested as a potential site for future disposal, such as 0.9 million m° of silty maintenance material from the proposed Boston Harbor Navigation Improvement Project and Berth Dredging Project (Normandeau Associates 1994). This material would be capped with approximately one meter of parent material that lies under the silts of Boston Harbor. Approximately half of BLDS lies below the 50 m depth contour on the slope of Stellwagen Basin. Based on the sedimentary fabric observed in the REMOTS® and plan view photographs, it was determined that below the 50 m contour BLDS is primarily a depositional environment and that there is no evidence to preclude its use for the deposition of silty dredged material. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 EPA SIDE-SCAN SURVEY 42°25' * ante) Dredged Material from Side-scan Survey Depositional Area (Knebel 1993) 42°23.500' 70°38.233' 42°19.550° 70°43.700° 70°40' 42°20' 42°19.550' 70°38.233' Approximate Proposed Disposal Location Figure 1-2. 42°15! The relative locations of dredged material located by side-scan sonar 70°35' (Schoenherr et al. 1992); 1994 REMOTS® sampling transects; a depositional sedimentary environment above the 50 m depth contour (Knebel 1993); and a proposed disposal location (Normandeau Associates 1994) Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 2.0 METHODS 2.1 REMOTS® Sediment-Profile and Plan View Photography The August 1994 REMOTS® sediment-profiling survey was conducted along six transects labeled C1 through C6. Transects C1, C3, C4, and C5 surrounded the DG buoy, and transect C2 was south of the buoy in an area of dense dredged material targets. This allowed us to maximize the potential of encountering dredged material (Figures 1-2 and 2- 1) and to focus on depositional areas determined suitable for future disposal (Normandeau Associates 1994). Transect C6 was situated in an area where side-scan records did not contain any targets interpreted as dredged material in order to assess benthic recolonization on ambient sediments located within BLDS. Two of the transects, Cl and C6, were oriented north to south while the remainder were oriented east to west. Each transect was 500 m long and consisted of ten stations spaced 50 m apart (a total of 60 stations; Table 2- 1). Two replicate photographs were taken at each station. Surficial sediments were photographed with a Photosea submersible plan view camera to permit evaluation of surface features including benthic animals and sedimentological features. The plan view camera was attached to the REMOTS® camera frame and photographed the sediment surface prior to camera frame touch-down in order to record an image of undisturbed sediments. 2.2 Sediment Grab Sampling Sediment samples were collected with 0.1 m’ van Veen grab sampler at three of the six transects (C2, C3, and C4) and at the reference area FG-23. Grab samples were collected at Stations 1, 5, and 10 (Table 2-1) of each transect for a total of nine grabs. Three replicate samples were collected at the reference area. Once the grab was brought aboard, four to five subcores were collected for chemical analysis, and the remaining sediment was saved for benthic community analysis. The chemistry subsample was composited in a teflon container and subsampled again for polycyclic aromatic hydrocarbons (PAHs), metals, and grain size/total organic carbon (TOC) analysis. The PAHs and metal subsamples were each placed in pre-cleaned 110 ml I-CHEM jars, and the grain size/TOC subsamples were stored in ziplock plastic bags. The remaining sediment set aside for benthic community analysis was sieved through a 500 micron screen. The residue was placed in one liter nalgene jars with both internal and external labels. Each biological sample was fixed in 10% formalin and stained with rose bengal, an organic stain. Following field collection, all sediment samples, Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 sjoosues) Suljdwes gSLOWAY “I-7 aansiy SIZ}9W mo-o€ Be OZO MO°ST Ov OZ4O MO"°00 2b O40 MO"GSb €bv OZ2O OOSE OOOE O0SZ 000% OOS! 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CP 86 12 ocv 1508 02 ocr S08 02 cP S08 02 cP S08 02 ocr S08 02 .cP S08 02 ocP S08 02 ocr S08 02 cP S08 02 och S08 02 .cP CLE LS oCP CLE LS oCP CLE LC ooP CLE LC ofP CLE LS oCP CLE LS ofP CLE LC ocP CLE LC oCP CLE LS oCP CLE LC oCP (p8SOM wWmeq suones oO — TNO TNOONR OOD i=) = TKTNO TNO OF OD SSSssSssSsSssSsssssssssssssssssss TFHNOTNO OPM OD eSLOWAY) SAT 38 surjdues T-¢ Fe L 289 OF OL bS9 OF O02 vl9OV OZ 1825 OF .O2 icvS OV .O2 COS OF OL 697 OF OL iC€v OV OL 96E OF OL O9€'0r .02, S98 OF OL 1828 OF O02 iC6Z OF OL 9S2'0r 02 612°0r 02 £89 OF OL 299 0¥ OL 019'0F .02 VLS OV OL LES OF OL iSC8 6E OL S28 GE 002 S78 6E OL S78 6E OL S28 6E .OL S78 6E OL S28 6E .OL S78 6E OL S286 OZ 1SC8'6E OL EN EN A CS NA | NN MR 0SS' LZ ocv 0SS'L2 .cV 0SS' LZ ocv 0SS' LZ .cV OSS LZ ocP 0SS' LZ ocv 0SS'1L2 ocP 0SS 12 ocP 0SS' 12 .cP 10SS' 12 ocP 87661 ocv i876 61 ocP 876 61 ocP 876 61 ocv 87661 cv 87661 cv 87661 ocP i876 61 ocP 87661 ocP 187661 ov 1898 02 ocP 1568 02 ocv 1026 02 CP 1676 02 ocP 226 02 och £00 12 ocv 0 AA 850° 12 och ‘S80 12 ocP CLL LS och KNMYT NOR DDLIIKNMYTNORADL|-nnmntrNnonaone @SLOWAY JO} suoneso7T Ja31e], uoNeIS Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 & biological and chemical, with the proper chain of custody forms were delivered to the US Army Corps of Engineers, New England Division (NED) laboratory where the samples were archived. 2.3 Navigation Navigation for the survey was provided by an SAIC Portable Integrated Survey System (PINSS). The PINSS is a PC-based system that receives navigation data, mathematically weights these signals based on signal strength (via a Kalman filter), and calculates both the position of the ship and the position error. The PINSS was interfaced to a Magnavox MX4200 Global Positioning System (GPS) with a Magnavox MX50R Differential-GPS (DGPS) receiver for vessel positioning with an accuracy of +5 m. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 3.0 RESULTS 3.1 REMOTS® Sediment-Profile Photography 3.1.1 Presence of Dredged Material Dredged material was observed at five of the six transects sampled (Figure 3-1; Appendix). Dredged material in the REMOTS® photographs appeared in two forms: 1) dark silty material typically found in dredged material throughout New England and 2) Boston Blue Clay (Figure 3-2, A and B). Boston Blue Clay, formed from silt and clay particles in glacial melt water, is a common constituent of material dredged from Boston Harbor (Camp, Dresser, and McKee, Inc. 1991). In most cases dredged material appeared as a horizon below a sandy mud layer of reworked sediments several centimeters thick and extended below camera penetration (Figure 3-3). However, in two instances (Figure 3-2, A and B) the sandy layer was very small or absent, and dredged material was near the sediment-water interface. Spatial distribution of dredged material was patchy. Dredged material was often seen in only one replicate per station even though the replicates were only a few meters apart. The two transects containing the greatest number of stations with dredged material (six stations) were C3 and C6 (Figure 3-1). Transects C1, C2, and C5 contained two to three stations with dredged material while none was observed at transect C4. 3.1.2 Grain Size Distribution Sediment grain size distribution was uniform throughout the area sampled. Sediments were predominantly silts and clays with a major mode size of >4 phi (Appendix). With the exception of two stations, C4-2 and 4, grain sizes ranged from very fine sands (3 phi) to silts and clays (>4 phi). Fine-grained sediments were overlain by a surface layer of very fine sands in most of the photographs. Stations C4-2 and 3 contained coarse-grained surface material as large as -1 phi. 3.1.3. Apparent Redox Potential Discontinuity (RPD) Depth The apparent redox potential discontinuity describes the region in which sediments change from a surface oxidizing environment to an underlying reducing environment. The depth of the RPD is determined by the net rate of transport of dissolved oxygen (DO) across the sediment-water interface, and the rate of consumption of DO in the sediment column. Mean apparent RPD depths (Figure 3-4), averaged for each transect by station, were between 1.5 cm and 2.0 cm below the sediment-water interface (Appendix). The Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 Sos3PUIl @SLOWAY 2) Ul poArosgoO sem [eLID}eU Paspoip d19YM JOoSuRI] Jad suONRIS JO JaquINU DY], «= *[-¢ BANSI sajey MO-O€ BE OZO MO°-ST Ot O40 MO-O0O ev O40 MO° St tv O40 OOSE OOOE O0S2 O00Z 00S! 000! 00S 0 JOUWSpOW PeHpsap ULM SUOIJDJS JO JOQUINN soo v6/L1/8 - OL/8 SHIS |DSOAsiq diys}y6r] uojsog a = == 7 er C ao et ‘es NO°OO 12 2p A - ¢ NO"OO Tz ev oF AON a te i se 99 ie 0 ee WOO Om SEeIOIZ0 MO°-S¥ 9€ O24O MO" O€ BE OZO MO" ST Ov OZO MO~ OO eb OZ4O0 MOE Sits ib —0/2'0 Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 ‘(q) aevyodjod [I] eeISg Surpssy ATOANOR OY} pur (YW) MOIING pal[tj-jo[[od os1e] ou} NON “(G) L-ZD pur (VW) OI-ED suonrRis 3 payeoo] Av[D on _ UOIsog soURIIATJoI YSIY ‘Avis WSIT «= °7-E VANS (a) (VW) Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 Figure 3-3. Layer of biogenically reworked sediments over dredged material and large Stage III polychaete feeding in the dredged material layer Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 13 (wd) syydap ANuQUOSsIp jeNuajod xopar jusiedde ase19Ae JOIsuRI], «= “p-¢ VANDI Sua} Oose OOOE O00SZ OOOZ OOS! OOO! 00S O Uuideqd dd v6/LL/8- OL/8 SIS |OSOdsiq diys}y6r] Uojsog NO" OO 12 2yv | -|- NO°Sv 22 ev | | MO- OO SE OZ4O MOs SID, BOE O20. MO"- Of 8E OZ4O MOS SiLSO:7 ss OFZ.0) MO°- OO ev O40 MO~SvV Ev O40 =e Iss 2h WS ISLE WS GGL NO" OO Té épv NO°Sb 22 ev MOO “8)e) O40) MO° SL Ov OZ4O MO- OO ev O20 MO°-Sb €b O40 Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 14 shallowest RPD depth measured was 0.73 cm, and the deepest was 4.76 cm (Figure 3-5). Because of shallow camera penetration, the RPD was deeper than penetration and could not be measured in 11 photographs. Of these eleven photographs, prism penetration ranged from 0.5 to 2 cm in 4 photographs, 2 to 3 cm in 6 photographs, and greater than 8 cm in one photograph. 3.1.4 Successional Stage Sediments at BLDS contained a relatively robust benthic community. Infaunal communities were dominated by the Stage II-on-Stage III class. Surface sediments at all stations were populated by stick-building amphipods (Family Podocerdiae; Figure 3-6, A). Sedentary polychaete tubes extended above the sediment-water interface at varying densities throughout the study area (Figure 3-6, B). Below the surface Stage II community, evidence of an abundant Stage II] community was commonly observed as burrowing polychaetes (Figures 3-3 and 3-2, B) and/or subsurface feeding voids (Figure 3- 7). Pelletized sediments, indicative of actively feeding infauna, were found near the sediment-water interface as well as inside feeding voids. Infaunal species were not limited to polychaetes; a bioturbating caudate holothurian Molpadia oolitica was photographed at C2-10 (Figure 3-8). In addition to infaunal species, several epifaunal species were observed including large mud anemones, hydroids, and bryozoans. 3.1.5 Organism-Sediment Index The REMOTS® Organism-Sediment Index (OSI) is a multiparameter tool used to evaluate the interaction of infauna and the sediment in which they live. OSI values can range between -10 and +11 and are based on RPD depth, successional stage, and the presence of methane associated with anoxic sediments. As there was no indication of low oxygen conditions, OSI values from BLDS were a function of RPD depth and successional stage. Values ranged from a minimum station mean of 5 to a maximum station mean of 10 (Appendix). Mean transect OSI values ranged from 6 to 9 (Figure 3-9). OSI values 26 are indicative of relatively healthy sediments. OSI values could not be calculated for twelve photographs: eleven due to indeterminate RPD depths, and one (replicate C1-7a) due to indeterminate successional stage. (The plan view photograph for replicate C1-7a shows the camera frame resting on a rock, restricting penetration.) 3.2 Plan View Photography The plan view photographs provided useful information about surface sediment characteristics which were not always discernible from the REMOTS® photographs. Surface sediments at BLDS were composed primarily of silts and sands (Figure 3-10). Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 Figure 3-5. Example of a thick RPD (4 cm) observed at Station C3-1 Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 16 Ayre, (q) sayoeyoxjod Buryjamp-sqm [J] ad¥Ig pue (VY :oeIprs90pod ) spodrydwre , 8urpying-yous,, (a) II a8e1S Aq pezuojoo SQ’Tg 18 SJUSUIpss voRJINg (Vv) 9 ¢€ 9 Inst] Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 17 we aes i Figure 3-7. Water-filled feeding void below the RPD at Station C6-4; note the halo of oxygenated sediments surrounding the void Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 Figure 3-8. Bioturbating caudate holothurian Molpadia oolitica at Station C2-10 Momitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 rv SJUOUUUOATAUO JOU pos a Ayyeoy APOAuLos uosoidos OS soneA [SO ‘SONPLA XOpUY JUOUTIPOS-UUSTULTIC, OPLIDAR JOOSURLT, — "G-E SUA | oe a : Ei | | | maw Mo’ Ot ue O40 MO' GUL OF O40 MO' OO 逥 O40 MO’ ov tbh O40 Oose OOOk 0OGF DOOF DOU D001 009 0 SON|DA [SO UbEe|\ ¥6/L1/8- OL/8 OIS |DsOdsiq] Ajys}yb)] Uojsog — ne 5 NO°OL GL ab i) 4a) No'OO te €i | - g = : - NO‘OO té ¢v AON OC vo. 99 NO‘ Gb 66 CV mn NO* OO Sk O40 MO’ Sb 9 O40 MO* Oe Ut 040 MO' St Ov O40 MO* OO ébv O40 MO’ Sb bY O40 20 sydeizojoyd MaIA ue]d ul Paarasqo soinjeaj} WI0}0q Jo AreWUNS *OJ-¢ aANSIY SIa}EW mMO~-O&€ BE O4O MO~ST Ov OZ4O MO° OO 2b OZO MO°-Sb Ev O40 oose ood OOSZ 0002 OOS! O00! OOS ) AJOUULUNS MIA UDI}d v6/L1/8 - OL/8 IIS |OsOdsiq diusjy6r] Uojsog NO°-ST 61 ev NO°OO 12 éyv | NO°~OO Ted edb NO°-Sb 22 ey | DUNDJIdZ= = Id S4OOa] PUD SBIQGOD = YOOU SON, WOM = IM 4IS/puDS= S/S M05 O10 Sie! (0/20: MOm Ss 918) 10/40) MOO CSIS ib /O/Z0, MO Site: OfVanOjZ0; MO~ OO ev O20 Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 21 While the resolution of the plan view photographs did not allow differentiation between fine sands and silts, sediments containing pebbles, cobble, and rocks were clearly evident. The plan view photos revealed two rocky areas, one at transect C1 and the other at C4 (Figure 3-11, A and B). The larger rocks at both of these sites were covered with silt and encrusting bryozoans. Many of the rocks observed had sharp angular edges and were probably disposed construction debris. Plan view photographs also provided information on the small scale horizontal distribution of the benthic community. In the plan view photos, both sedentary infaunal polychaete tubes and epibenthic species were observed. Infaunal tubes were present at all six transects. Tube distribution was patchy and rauged from dense mats (Figure 3-12, A) that carpeted the bottom to absence (Figure 3-12, B). Epifauna observed at BLDS included mud anemones, seastars, hydroids, gastropods, and bryozoans. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 22 Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 (B) (A) Figure 3-11. Possible construction debris—large, sharp-angled, silt-covered rocks observed in plan view photographs from transects C1 (A) and C4 (B) 743} (q) Juasqe Ayreau 0} (Y) Jodie asuap & WoO SuIsUeI saqm ajoeyoATOd dovjJANs JO UONNQINSIP snosussolo}OH{ “ZT -¢ WMS (dq) (Vv) Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 24 4.0 DISCUSSION 4.1 The Sedimentary Environment of BLDS An understanding of the sedimentary environment at BLDS is necessary to determine if there is evidence to preclude its suitability for dredged material disposal. For example, the preferred locations for silty dredged material, such Boston Harbor sediment, have been in low-energy environments where sediment resuspension and transport is minimal. BLDS is located between the 40 m and 70 m depth contours on the western slope of Stellwagen Basin in Massachusetts Bay. The seafloor of Massachusetts Bay can be divided into three major sedimentary environments: 1) areas of erosion or nondeposition; 2) areas of sediment reworking, a combination of erosion and deposition; and 3) areas of sediment deposition (Knebel 1993). The distribution of these sedimentary environments reflects the dominant processes in operation. Areas in the bay subjected to high-energy (erosional) conditions tend to be characterized by coarse glacial drift and bedrock outcrops while areas of lower energy (depositional) are characterized by fine-grained sandy muds (Knebel 1993). Through a compilation of sonographic, photographic, and direct sediment sampling, Knebel mapped these three sedimentary environments from the Massachusetts Bay coastline to the 50 m depth contour of the continental shelf. Knebel's maps indicated that erosional and sediment reworking environments comprise the majority of the shelf bottom in the Bay. Depositional environments are found primarily in Boston Harbor and at the 50 m contour of the Basin slope. The transects used in the present survey are all just beyond the area characterized by Knebel (1993). Based on Knebel's (1993) sedimentary environment maps, the majority of the Massachusetts Bay Inner Shelf region is composed of erosional and sediment reworking environments. However, deeper depositional areas appear along the 50 m depth contour (Figure 4-1). This depositional zone begins within the southern portion of BLDS (Figure 1-2), but was not mapped in the initial study of Massachusetts Bay. The REMOTS® and plan view photographs provided some insight about the nature of the sedimentary environment within BLDS and support the extension of the depositional regime mapped by Knebel north and eastward into the disposal site. Grain sizes at BLDS below the 50 m depth contour ranged from very fine sands (3 phi) to silt plus clay (>4 phi) with a major modal size of silt plus clay. Sediments in depositional environments of Massachusetts Bay are composed primarily of sandy muds and muddy sands and have average concentrations of 0.5% gravel, 45.8% sand, and 53.7% silt plus Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 25 CYayew ' Sar 7°00 70°50 o. - 70°30'W DEPOSITION 42°30'N + ‘Unmapped Area 42°10’ 10 Kilometers Location of depositional environments in Massachusetts Bay from the shore Figure 4-1. to the 50 m depth contour (from Knebel 1993) Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 26 clay (Knebel 1993). Following this definition the areas sampled may be described as depositional environments. Defining an area as a depositional environment does not preclude the potential for resuspension of fine-grained particles, but merely implies that the combined result of the dominating dynamic processes is net sedimentation. The deficiency of silt/clay particles in the upper centimeter compared to deeper sediments is at least in part due to episodic resuspension. The smaller fine-grained particles are more easily entrained in bottom currents and are winnowed from the surface sediments, leaving behind coarser grained material. Although periodic resuspension may occur during the stormy winter months (Knebel 1993), there is no evidence of extensive sediment movement that might limit the future use of this site for dredged material disposal. 4.2 Presence of Dredged Material The primary purpose for this survey was to examine a historic unconfined disposal site and attempt to determine if any deleterious environmental conditions still persist nearly twenty years after disposal activity had ceased. The combined use of side-scan sonar with REMOTS® sediment-profile and plan view photography allowed the 1994 reconnaissance effort to be focused on areas where dredged material, and the need for remediation, was more likely. Disposal of dredged material at BLDS was widespread with material deposited in localized patches throughout the site. The highest concentrations of dredged material, located by side-scan sonar, encompassed the former DG buoy location and extended south below the 50 m depth contour (Figure 1-2). REMOTS® photographs collected from the transects surrounding the DG buoy location and to the south confirmed that the side-scan records were indicative of dredged material deposits (Figure 3-1). However, the presence of relic dredged material at transect C6, where no dredged material was detected in the side-scan survey, indicates that limitations exist in the use of side-scan sonar as the only tool for locating relic dredged material. Side-scan sonar, by detecting changes in the acoustic signature of the surface sediments, displays patterns that are characteristic of dredged material disposal. When dredged material is spread over a wide area or buried beneath the surface, side-scan sonar may not detect it. Dredged material in the regions surrounding the DG buoy was light gray, high-reflectance, fine-grained Boston Blue Clay (Figures 3-2 and 3-3). This material may be part of the 2.3 million m? of Boston Harbor dredged material deposited in the 1960s and 1970s (Normandeau Associates 1994). Even though fine-grained dredged material was not observed in the REMOTS® images from transect C4, which was also located in an area of concentrated dredged Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 Pui material targets, the plan view photographs revealed areas of cobble and larger sharp- edged rocks (Figure 3-11). The sharp angularity of the rocks, and their presence at a known disposal site, suggest that they may be construction debris. More solid evidence that transect C4 contained construction debris was found while sieving one of the grab samples. A small rounded piece of concrete with two planar sides was found in the grab sample from Station C4-5. This small piece probably was bored from a larger slab either for blasting or attachment of lifting cables. 4.3. Benthic Recolonization The identification of a dredged material signature on side-scan records, and the further investigation of the dredged material by REMOTS® sediment-profile photography, were necessary to determine if remediation was needed. The primary step in determining if remediation was required at BLDS was to examine the status of benthic recolonization and compare the dredged material with apparent ambient sediments within the disposal area. There was no preexisting reference area for BLDS; however, the ambient sediment at Station C6 should provide a good basis for comparing the effects of dredged material disposal on the benthic habitat. Information derived from sediment structures was compiled into the multiparameter REMOTS® Organism-Sediment Index. At BLDS the OSI value was primarily a function of the successional stage of the populating infauna and the depth of biogenically enhanced oxygen penetration (RPD). The most striking evidence for a healthy benthic habitat at BLDS was the abundant and diverse benthic community. The subsurface sediments were populated by burrowing polychaetes both large and small as well as other Stage III genera including caudate holothurians (Figures 3-2, B; 3-3; and 3-8). The surface sediments were dominated by sedentary, tube-dwelling Stage III polychaetes and by Stage II stick-building amphipods (Family Podoceridae) (Figure 3-6, A). The presence of Stage II organisms in the surface sediments is probably from secondary colonization, and not indicative of a recovery from a recent disturbance. Following disposal activity and the progression of recolonization to a Stage III community, the Stage III organisms began to feed in deeper sediments. The movement of the Stage III group out of the upper sediment cleared space for reoccupation by surface-dwelling Stage II infauna. In addition to the abundant benthic community, several pieces of information from the sedimentary structure suggested a healthy benthic habitat has persisted for some time. Numerous water-filled voids were observed in subsurface sediments (Figures 3-2 and 3-7). These voids were created by the feeding activity of head-down deposit feeding Stage III organisms. A halo of oxidized sediments, which surrounded the voids, suggested recent Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 28 active feeding. In addition, several of the voids contained coarse-grained particles that were presumably discarded during particle-selective feeding habits (Figure 3-7). Despite the healthy benthic community at BLDS, the RPD values are relatively shallow. Normally, the combined activity of the subsurface burrowing Stage III organisms, the sedentary tube-dwelling polychaetes, and surface-dwelling Stage II infauna served to transport oxygen into the sediments resulting in relatively deep RPD depths. ' While irrigating their tubes, sedentary tube-dwelling polychaetes pump high dissolved oxygen concentration seawater out of the tube bottoms directly into the sediments, forcing a unidirectional upward displacement of interstitial fluid. However, the net diffusion of dissolved oxygen from seawater injection and subsequent advective porewater transport will be less where there is high sediment oxygen demand (SOD). With high SOD, oxygen that is transported across the sediment-water interface is rapidly consumed by microbial respiration and oxidation reactions. The observed RPD depths of only a few centimeters at BLDS, combined with a well-established infaunal deposit-feeding community (Figure 3-5), suggest that BLDS sediments have relatively high SOD. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 29 5.0 CONCLUSION The reconnaissance plan view and REMOTS® sediment-profile surveys identified areas of historic dredged material at BLDS. The identification of dredged material by these surveys was accomplished with a low level of effort by focusing on areas targeted for the presence of dredged material in the side-scan sonar survey of BLDS. However, dredged material was also found in an area devoid of side-scan sonar targets, and some areas of side-scan sonar targets did not yield the expected fine-grained dredged material. Side-scan sonar has a limited ability to locate relic dredged material. This technology is unable to detect dredged material that does not present a distinct surface acoustic signature. Even when a distinct surface feature is present, the disposal pattern may be due to rock or construction debris which is impenetrable to REMOTS®. Based on the results of all surveys, dredged material at the site was distributed in patches over both large (side-scan sonar) and small (REMOTS®) horizontal spatial scales. Sediments which can support the level of recolonization observed at BLDS generally should not require remediation action, only periodic monitoring (Germano et al. 1994). Twenty years after the cessation of disposal activity, the benthos of BLDS has a Stage II and Stage III benthic community. The presence of these communities and the evidence for extensive biogenic reworking of dredged material suggest a healthy benthic habitat. Chemical analysis of the archived sediment samples is not recommended at this time for the purpose of evaluating remediation. If the site is designated for additional disposal, these archived sediments might be analyzed for evaluating baseline conditions. The depositional environment characterized at BLDS beyond the 50 m contour shows no evidence to preclude its use for future dredged material disposal. Any resuspension and transport that may occur is most likely episodic and does not occur frequently. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 30 6.0 REFERENCES Benoit, J. M.; Torgersen, T.; O'Donnell, J. 1991. An advection/diffusion model for Rn- 222 transport in near-shore sediments inhabited by sedentary polychaetes. Earth Planet. Sci. Letts. 105:463-473. Camp, Dresser, and McKee, Inc. 1991. Environmental consequences of utilizing Boston Blue Clay in landfill closures (Subtask 8.2). (Index and Section 3). Central Artery/Tunnel Project, Rowars Task Assignment #1 Materials Disposal, Massachusetts Department of Public Works. DeAngelo, E. 1993. Quantification of porewater transport rates during hypoxia in Long Island Sound. University of Connecticut. Unpubl. MS thesis. 117 p. Germano, J. D.; Rhoads, D. C.; Lunz, J. D. 1994. An integrated, tiered approach to monitoring and management of dredged material disposal sites in the New England region. DAMOS Contribution No. 87 (SAIC Report No. 234). US Army Corps of Engineers, New England Division, Waltham, MA. Knebel, H. J. 1993. Sedimentary environments within a glaciated estuarine-inner shelf system: Boston Harbor and Massachusetts Bay. Mar. Geol. 110:7-30. Martin, W. R.; Sayles, F. L. 1987. Seasonal cycles of particle and solute transport processes in nearshore sediments: Rn-222/Ra-226 and Th-234/U-238 disequilibrium at a site in Buzzard's Bay, MA. Geochim. Cosmochim. Acta. 51:927-943. Normandeau Associates Inc.; US Army Corps of Engineers. 1994. Boston Harbor navigation improvement dredging, Berth Dredging Project. Draft Environmental Impact Report/Environmental Impact Statement v1 & 2. Submitted to Massachusetts Port Authority, MA and US Army Corps of Engineers, Impact Analysis Division, Waltham, MA. Rhoads, D. C.; Germano, J. D. 1982. Characterization of organism-sediment relations using sediment profile imaging: an efficient method of remote ecological monitoring of the seafloor (REMOTS® system). Mar. Ecol. Prog. Ser. 8:115-128. Rhoads, D. C.; Germano, J. D. 1986. Interpreting long-term changes in benthic community structure: a new protocol. Hydrobiol. 142:291-308. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 3] Schoenherr, J.; Cook, J.; Carey, D.; Tracey, G. 1992. Location survey and condition inspection of waste containers at the Boston Lightship Disposal Ground and surrounding area. Draft Final Cruise Report for Work Assignment 13, Task 4. Submitted to US Environmental Protection Agency, Environmental Research Laboratory-Narragansett, Narragansett, RI. Monitoring Cruise at the Historic Boston Lightship Disposal Site, August 1994 oes aie So uni cit . me he 7 aH ee ieee ml Bust) ba Die INDEX anoxia, 19 waste, 1, 6 barge, | winnowing, Vi benthos, vi, 1, 7, 8, 19, 29 amphipod, 19 epi, 19, 29 polychaete, 17, 19, 29 bioturbation feeding void, 19, 24 buoy, 1, 6, 7 deposition, vi, vii, 4, 6, 7 dissolved oxygen (DO), 13 feeding void, 19, 24 grain size, vi, 7, 12 habitat, vi hydroids, 19, 29 methane, 19 organics polyaromatic hydrocarbon (PAH), 7 total organic carbon, 7 recolonization, vi, 1, 7 reference area, 7 REMOTSS, vi, 1, 4, 6, 7, 12, 19, 20 Organism-Sediment Index (OSI), vi, 19 resuspension, Vi RPD REMOTSS®, redox potential discontinuity (RPD), 12, 19, 22, 24 sediment clay, vi, 12 cobble, 29 resuspension, Vi sand, vi, 12, 29 silt, vi, 12, 29 sediment sampling grabs, 7 species dominance, 6 successional stage, 19 trace metals, 7 pec lles Elen 2 Sate boy fetontls o eaten TiN aay ay PVT ie APPENDIX 5 Real aie a iin, ats ee stun 1yd = 9ZIg uleID aJeuluajapuy = LHANI 8 Ill 2 eS 0 Gilwe A) Ol 1D LE III 9881§ NO II 2381S 0 cl p< O€ p< L779 q Ol 1D 8 III 9381S NO II 9381S 0 907 v< OE v< 879 A) 6 1D 8 III 9381§ NO II 2381§ 0 SLI 8 67< O€ v< OIL e 6 1D 8 III 2381§ NO II 2381§ 0 pL. p< OE p< 9¢ ‘01 A) 8 1D LAGNI LAGNI 0 LST 8 6p< OE p< Ov'Z B fi 1D 6 ‘If, 9881S NO I] 98k 0 6h 7H COVE p< 9°01 q 9 ite) 6 IIT 8881S NO II 2881S 0 Cie ELS OE p< tr'6 e 9 fe) 8 III 2381§ NO II 28e1§ 0 OLI p< OE p< 61°71 9 ¢ 1D 8 III 9881S NO II 9881S§ 0 OLI p< OE v< Clee e ¢ 1D 8 III 9381§ NO II 9881S 19°6 907 r< O1€ p< L7'6 q p iD) 9 I] 23815 0 6SIl v< OE p< 767 e v 1D 8 III 9381§ NO II 9881S 0 L461 v< OE p< LE9 q € 1D ¢ I] 2385 Z0'7 Col p< OE p< COL B € ID 8 III 238§ NO II 23e1§ 0 0G pore p< 00°01 a) Z 1D 8 III 2381S NO II 98e1S 0 L102 p< ‘OE p< 6601 q 6 1D 8 III 9881§ NO II 2881S 0 GSile “p< ONG p< LSU Pp I 1D 8 Ill 2381S NO II 9881S 0 E91 p< OE p< 00°8 q I ite) 3381S Jeuorssaoon¢s (Wid) UoHensegG dda asuey «=: BpOJ JOlepy (Wd) UONeNsUsg ayeol[dsy woNeIg JoosuelL Jelayey] pospsiq I3VJOAY 9ZIS UIBID 9ZIg UieID oBelIAYV BEC aYO1g-jUIWMIpIsS gS LOWAY syun 1yd = azig ulelg ayeuluLajapuy = LACNI III 2381S NO II 9981S II 2881§ NO II 93%S Ill 9381$ NO II 98k III 288$ NO II 93k II 2381$ III 2881§ NO II 98815 III 238§ NO II a3eS I] 9381S Ill 2381§ NO II 23%S I] 2881S III 2381§ NO II 93k II 9381S Ill 238§ NO II 9881 III 9881§ NO II 23e1¢ II 281 III 2381§ NO II 298 I] 9881S III 2381§ NO II 93k I] 9881S JaXe] paonpal Wd QI] III 2381$ NO II 2385 vs'l a8e1S$ wd uoneloued ddu asuey apow/- Joly wd uonenouod ayeol[day uones JyOosuely JeuOIssa00Nn¢g jelloje yy pospaq aselaAy aZI§ uleI£y 9ZI§ ule‘) aselIAY 9ST CLT 9'T £9°C LHCNI Aeme |[nd 981 LAGNI L6'1 7 T 90°7 9ST CLT 8L'I pnul/pues pnul/pues Sel 8S oo = co t+ soe O 8S O SS O mANANINMNMTATMNMNM OOM MH CO CON AN SCD ie COS CS eC) CS: cok un CS to OSU oka) 0 0 0 ¢: 0 0 ¢: 0 0 0 96 0 0 0 0 0 0 0 0 0 oO — (panuyjuos) Beq ayorg-jaUNIpsg gS LOWAY sun tyd = azig uleip aeuluLIa}apu, = LACNI III 9881§ NO II 98e1§ 907 p< OE v< evs III 2381§ NO II 9381 9b p< PH p< 161 III 9381$ NO I] 2881S ILTG ES ONS p< 06°S III 9381S NO I 9881S ; Iv'€ p< OE p< 19°8 Ill 2381§ NO II 9385 CsI p< OE p< 8's I] 28k I6T p< OE p< Clee III 2381§ NO II 2381S ISt p< og v< 7O'L III 2381§ NO II 3881S 0 PTE “P< OE p< ETL III 238§ NO II a8eI¢ 0 LOE p< OE p< b6'S I] a3e1¢ 0 09% p< OE p< b6'S Ill 2381 NO II 93815 0 (G7 Sale p< 79'L III 2381§ NO I] 2881S ) Pll p< O1€ p< 6¢$'9 III 2381§ NO II 938815 76'S 6LT p< OE p< 17s III 2381§ NO II 98815 bO'L GEG Axs ONS p< 60°9 Ill 2381§ NO II 93e1$ 16 COiGaee F< Ole p< 78°8 III 9381$ NO II 9881S ELL rT p< OE p< SUL Ill 2381§ NO II 9381$ 0 OFZ p< OE b< €v'L III 2381§ NO If 93815 ai OOF H< OE v< 1€°6 Il] 2881§ NO II 9881S 0 66€ p< OE v< 966 £0 III 9881§ NO II 9881S 0 6b7 = p< “OLE p< €r'Ol I €) 9381S (WD) UonNeNIegG §dd¥ asuey apoy Joleyy (Wd) UoNeNaUSg ajeaday UoTeIS OasueI], euoIssaoon Bae pospeiq sselaAy 9ZIg UleIg azig ulel a3PIIAY £0 £0 €O £0 £0 70) £0 €0 £0 £0 £0 £0 £0 £0 £0 £0 £0 10) oo = = SOtOtsO SFO BGO SO SFCH SH GSO Yv ANNAN NTANMN OOM Mm COONAN A (panuijuod) ejeq aljo1g-jUIUMIPaS gS LOWAY sun 1yd = azis ulein syeuluajapuy = LHCNI III 9581$ NO II 9981 I] 9388S II 28e)¢ II 9381S III 238§ NO II 9381S III 9881$ NO II 9381S I] 9381S I] 9381S LACNI I] 9381S III 9381§ NO II 28e1$ ITT 9¢'1 Ndd < dda 00°T LO 781 c8'0 €L°0 LHdNI 00°T 081 LSI LACNI v8 08'T tv ere €C Pv ELI Lol Wd) UONeNaUag ddu asuey apoyy Joleyy (wd) uoneNousg ajeoday uonejg yoosuel] jeuoissasons [ela paspeiq aseloAy azig uIeIy azisg uleIn aselOAV I] 23815 LAGNI III 2381§ NO II a8eI1¢ IJ 9381S III 2381§ NO II 38e1§ CS Co 1o1e1S 6 Ono SC SexeclorenoriorerS —“=ANNaAMNATTNHHOUORKRWADADSS i=) (penuljuod) Bed atjo1g-JUIUNIpIg gS LOWAY sjtun tyd = 921g uleID aVUIULIOJ9puy = LACNI LAGNI LAGNI 0 LAGNI p< O1€ p< 7S'0 q Ol se) LAGNI III 9881S NO II 93e1S 0 Ndd