Ge Sree Ss que WES Tech. Ke e- GUNS A Technical Report CHL-97-13 July 1997 US Army Corps of Engineers Waterways Experiment Station Monitoring Completed Navigation Projects Program Monitoring of Harbor Improvements at St. Paul Harbor, St. Paul Island, Alaska by Robert R. Bottin, Jr, WES Kenneth J. Eisses, Alaska District Approved For Public Release; Distribution Is Unlimited Sk aE, wad 5), CU : ) Prepared for Headquarters, U.S. Army Corps of Engineers ~ [oles ee The contents of this report are not to be used for advertising, publication, or promotional purposes. Citation of trade names does not constitute an official endorsement or approval of the use of such commercial products. The findings of this report are not to be construed as an official Department of the Army position, unless so desig- nated by other authorized documents. EB ranren ON RECYCLED PAPER Monitoring Completed Navigation Technical Report CHL-97-13 Projects Program July 1997 Monitoring of Harbor Improvements at St. Paul Harbor, St. Paul Island, Alaska by Robert R. Bottin, Jr. U.S. Army Corps of Engineers Waterways Experiment Station 3909 Halls Ferry Road Vicksburg, MS 39180-6199 Kenneth J. Eisses U.S. Army Engineer District, Alaska Anchorage, AK 99506-0898 Final report Approved for public release; distribution is unlimited UU MI O 0301 0091425 5 Prepared for U.S. Army Corps of Engineers Washington, DC 20314-1000 san US Army Corps of Engineers Waterways Experiment Station FOR INFORMATION CONTACT: PUBLIC AFFAIRS OFFICE U.S. ARMY ENGINEER WATERWAYS EXPERIMENT STATION 3909 HALLS FERRY ROAD VICKSBURG, MISSISSIPPI 39180-6199 PHONE: (601) 634-2502 AREA OF RESERVATION « 2.7 sq kes Waterways Experiment Station Cataloging-in-Publication Data Bottin, Robert R. Monitoring of harbor improvements at St. Paul Harbor, St. Paul Island, Alaska / by Robert R. Bottin, Jr., Kenneth J. Eisses ; prepared for U.S. Army Corps of Engineers. 123 p. : ill. ; 28 cm. -- (Technical report ; CHL-97-13). Includes bibliographic references. 1. Harbors — Alaska -- Saint Paul Island. 2. Saint Paul Island (Alaska) I. Eisses, Kenneth J. IL United States. Army. Corps of Engineers. IM. U.S. Army Engineer Waterways Experiment Station. IV. Coastal and Hydraulics Laboratory (U.S. Army Engineer Waterways Experiment Station) V. Monitoring Completed Navigation Projects Program (U.S.) VI. Title. VII. Series: Technical report (U.S. Army Engineer Waterways Experiment Station) ; CHL- 97-13. TA7 W34 no.CHL-97-13 Contents reba Ce ee ee eae UAT pa NE IAS Reiss De Sa Wi es ea MMS acti a Vili Conversion Factors Non-SI to SI (Metric) Units of Measurement .............. x TEP GUICET OTT See aoe eee We VA LEs CaN caTCol aT ea SESTES peg ous one eee oan suse 1 Monitoring Completed Navigation Projects Program .................+--- 1 Project Location and History ................------22--+e+0+- +e eeeee 2) Harbor Developmentasmme creer eee cacti teeta rrr 3 Hydraulic Model Studies of the Harbor .............---..+++--- +e eee eee U DN OMOvaNR ACVB ps bioodiaonodocodcococecogdevcacspcaneononcodnd 16 IM@iMoaT IBM copecncdooseooesdoocdoddoonpspotgoouodouengncacar 16 Equipmentand Data Collection seer eerie eer 18 Data Resultsiand!Discussion’... 1-4 soos nae oe fe eee ace. 30 3—Conclusions and Recommendations ............--22e eee eee eee teens 57 (GOL S TOMS eee each ee eat nse euay eee Se ea Green Sins ee ayers oes siatseaweastepeals 57 RECOMMENGALIONS ee ee ornare Rasen leaeee oe ees sas ENE Soa etd neta castle ehoucey aason 58 RefEReTC SST jee se ene hm coe eae sleep SCL SL HRT Rl pewe Wale foes ta ine eariauereh suomi uealotra te 59 Tables 1-6 Appendix A: Breakwater Topography, 1996..............--.--+-2.----- Al Appendix B: Changes in Breakwater Elevations Between 1994 and 1996..... Bl Appendix C: Breakwater Cross Sections, 1994 and 1996.................- Cl SF 298 List of Figures a igure) a broject location rier taiieet tere eer tener 3 Figure 2. Layout of St. Paul Harbor ...............-.--.--+2.---+----- 4 Figure 3. Aerial view of St. Paul Harbor.....................-2--0--0-- 5 ili Figure 4. Figure 5. Figure 6. Figure 7. Figure 8. Figure 9. Figure 10. Figure 11. Figure 12. Figure 13. Figure 14. Figure 15. Figure 16. Figure 17. Figure 18. Figure 19. Figure 20. Figure 21. Figure 22. Figure 23. Figure 24. Figure 25. Figure 26. Figure 27. Figure 28. Figure 29. Typical breakwater cross sections .............2...20eeeeeeeee 6 3-Dimodel layout jee.) hands suites seinen eae cate Steen 8 Generaliview/ol3-D modeli- eee enna elee hoe beeen ene 9 Layout of recommended 3-D model test plan .................. 10 Typical wave patterns for Plan 47; 14-sec, 4.9-m (16-ft) test WAVESHTOIMNGWES Barts: sik tela seen cece GON, apes inca nes Rear 11 Typical current patterns and magnitudes (prototype feet per second) for Plan 47 for test waves from west .................. 12 General movement of tracer material and subsequent deposits for Plan 47 for test waves from west-northwest ................ 13 Wave) flumecross'section j-s.45 oe ae eee iaaiene 14 Cross section of recommended breakwater .................... 14 Model view of recommended breakwater cross section .......... 15 Prototype gauge locations at St. Paul Harbor .................. 19 Coarse grid used for initial stage of wave hindcast study ......... 21 Fine-resolution grid used for final stage of wave hindcast study ... 22 Video camera used to obtain runup data ...................... 23 Ground control points (GCP’s) and profile (PFL) locations established on breakwater ................--- 00. e eee eeeeee 24 View of collection box used for measurement of wave OVETLOPPIN Ge Gee ere hoa ks ened ene Ara seg cllayel oe Ds Flow transducers and recorder used to determine overtopping TACOS ce hes ois Ais che ENA, Ve RSI Meise bel cane yatta ccs fe pa a ie 26 Massive overtopping of St. Paul Harbor main breakwater on SrNovemberw O94 oc ie tartare atest tuchoya oy cusne \owewey nop eeReree NG 27 Collapsed apron resulting from 3 November 1994 storm......... 27 Example of target established on St. Paul breakwater ........... 29 Bathymetry at St. Paul Harbor, September 1986 ............... 33 Bathymetry at St. Paul Harbor, August 1992 .................. 34 Contours of bathymetric changes between September 1986 and Aoustel O92 sunVveySinme sae eee eee ea ec 35 Bathymetry at St. Paul Harbor, July 1995 ..................... 36 Contours of bathymetric changes between August 1992 and July TOOSASUEVEYS. ie Dike arate Nae A eh cH rel SO es uanemetrere ities. caste rae 37 Areas at harbor entrance selected for detailed analysis ........... 38 Figure 30. Figure 31. Figure 32. Figure 33. Figure 34. Figure 35. Figure 36. Figure 37. Figure 38. Figure 39. Figure 40. Figure 41. Figure 42. Figure 43. Figure 44. Figure 45. Figure 46. Figure 47. Figure 48. Figure Al. Figure A2. Figure A3. Detailed bathymetry in Areas A and B for September 1986 Detailed bathymetry in Areas A and B for August 1992 survey ... Detailed bathymetry in Areas A and B for July 1995 survey ...... Cross sections through Area A, Section A-A for 1986, 1992, and MQOSNSUEVEYS iy sishm ah cinranls sie icecree is maaeay av stoteretsyoha lanes atc talaiey semnoley chcieals Cross sections through Area B, Section B-B for 1986, 1992, and UOOSISUEVEYS exer cic siesta ete keee oy misue Sine eesmaneh ammmvanauersrse tose Cross sections through Area A, Section C-C for 1986, 1992, and BOOSASURVEYVSiy ates re clniatia sh epee alopenes tertile yaaa arene acta ele erate Contours of bathymetric changes in Areas A and B between September 1986 and August 1992 surveys .................... Contours of bathymetric changes in Areas A and B between August 1992 and July 1995 surveys ...............-.2------- Contours of bathymetric changes in the lee of the eastern end of the detached breakwater between September 1986 and July 1995 .. Approximate locations of broken/cracked armor stone on outer breakwater during June 1996 survey ......................... View of broken armor stone on St. Paul Harbor breakwater (Gtation lO 2 Miers Bie severe essen ovata ec anercie celine os ersicaraies aie negate tote View of broken armor stone on St. Paul Harbor breakwater (Gentes ILE S7 ASS) ia Sis ye teeth eel oie eieieeane orale carr ereca.crateo Rin crac ors View of broken armor stone on St. Paul Harbor breakwater (Stations HERO) ier ceccutis cores crease ara h sioen ty ale emcee anna acted View of broken armor stone on St. Paul Harbor breakwater (Stations lS Ayo icuscrs racers re icpaee ersten cop ou eiya oe re SRA say a aneiene Locations of monuments and targets for 1994 survey ........... Locations of monuments and targets for 1996 survey ........... Example of stereo pair photos for a portion of the breakwater in May 99 Gre ie eens aya Suerte Mensa rata aan Mena al usrelitran cade eu Orthophoto for a portion of the breakwater in May 1996......... Point plot map of a portion of the breakwater in May 1996....... Topography of St. Paul Harbor main breakwater, May 1996, StaiG 842/84 wept, erent cal tar et Seu etal Seton state (op stclcusestieasee Topography of St. Paul Harbor main breakwater, May 1996, Stay7AS44-B4-84 jay trc he ta nlite whet Shae pehalalls Wie lets Valekeialicta ies clahele inode istenche Topography of St. Paul Harbor main breakwater, May 1996, Star SH BAO HSA ie rak coarse seua ene lapascticin oteicetleweitrsuetesraretel suciorevnisnens vi Figure A4. Figure A5. Figure A6. Figure A7. Figure A8. Figure A9. Figure A10. Figure A11. Figure A12. Figure B1. Figure B2. Figure B3. Figure B4. Figure BS. Figure B6. Figure B7. Figure B8. Figure B9. Figure B10. Topography of St. Paul Harbor main breakwater, May 1996, Sta 9+ S410 ESA orca a cuslaiat silat chants acc PRR SALI aay Sean A5 Topography of St. Paul Harbor main breakwater, May 1996, Sta lOtS4-V VB ye ae cots Als Senne everest eye eters occa yews A6 Topography of St. Paul Harbor main breakwater, May 1996, Stal S4=1 2484 os toe sla sais a evel s seemayeln cle eg wns e ANE Wi ets oe A7 Topography of St. Paul Harbor main breakwater, May 1996, StaUl2 +841 SSA a asd os. sah deers een ONL Bi al aie een seek ye A8 Topography of St. Paul Harbor main breakwater, May 1996, Stal S+ Ota LAO se wae laecre toes bedege seas Atay eR ate ee A9 Topography of St. Paul Harbor main breakwater, May 1996, StaHlA TS 4 eV SA SA eee tes, oval ot raat tata rat seat anebehanadeuee Oeatlagiate ca ce vee Al10 Topography of St. Paul Harbor main breakwater, May 1996, Sta SSA O SS a leas caace tl nabers ates (onattenonen sie pauaaysierareshelarele All Topography of St. Paul Harbor main breakwater, May 1996, Sta OPS 41 TS cc. ncn eroresetorpoeeee neve ee easie anata echoes Al12 Topography of St. Paul Harbor main breakwater, May 1996, Sta T7+84-18 00s eis r2a4¢ SST A EERE EEE EEE EE EERE EME TEE eter on BEGRRRODE PO Te SLUe Coo a EEE EEEEEEEEECEEEL EEE AEH COMET LEE EEE Cee eee 40°E 166°30°E 171°30°E 176°30°E 178°30°W 173°30°W 168°30°W 163°30°W 158°30°W Longitude Figure 15. Coarse grid used for initial stage of wave hindcast study data input for the model was obtained from the Mass Storage Facility and inter- polated from the standard 1-deg spacing to fit the finer array of input grid points. The WIS model then was run for the months covering mid-October through mid- December 1994, using additional wind information over the month of September 1994 for model spin-up. This stage was considered a deepwater application, and no water depths were required to complete model input. After calibration of the hindcast model for the initial stage grid, additional runs were completed to establish boundary input for the more refined final stage grid. Spacing for this grid was 1 min (0.017 deg). Global wind fields could not be inter- polated with accuracy due to the fine grid spacing. This appeared not to present a problem, however, since the distance between input boundary condition points and the output location was deemed small enough to make omission of the winds acceptable. The shallow-water nature of this application made it necessary to include water depths over the entire final stage grid. Output was obtained seaward of the St. Paul Harbor main breakwater. Peak wave periods and significant wave heights were obtained covering the period mid-October 1994 through mid- December 1994. Chapter 2 Monitoring Program 21 aan Hil il TT Hil Hil Hae nil dt oil sil aba alae WOU iii WO are Model Output rT RIA | | LETT TT AL eg td N.O6,49 N.¥0,49 N.81,29 N.ZI,29 epnine] Longitude Figure 16. Fine-resolution grid used for final stage of wave hindcast study Chapter 2 Monitoring Program 22 Wave runup Wave runup on the face of the St. Paul Harbor main breakwater was obtained with a videotape system. This technique has been used previously to measure runup on beach slopes, but was modified to secure breakwater runup for St. Paul. A video camera was set up and mounted on the cliff south of, and overlooking, the harbor (Figure 17). Four ground control points (GCP) along the breakwater crest and two profile locations (PFL) along the breakwater face were established as shown in Figure 18. The x, y, and z coordinates of the camera location, the center of the GCPs, and points along the PFLs then were determined to establish the required geometry. By using the GCPs as control and knowing the profile, a time series of wave runup was generated. The surface of the water on the structure was digitized six times per second along the breakwater PFLs. Digitization was completed from videotape. The data can be retrieved, displayed on a monitor, and analyzed for runup time series. This technique has the advantages of being low-cost, logistically simple, and providing relatively accurate measurements. More information on obtaining wave runup through videotaping techniques may be found in Hathaway, Howd, and Oltman-Shay (in publication). Figure 17. Video camera used to obtain runup data WES personnel were onsite and obtained videotape footage during the mid- October through mid-December 1994 time period. The camera was mounted and connected to a recorder, and videotape footage was generally obtained twice daily for 30-min durations. A log book was maintained during periods when the data were collected. The videotapes were analyzed to secure wave runup time series and subsequent vertical runup data. Data were initially generated for both PFLs, but since they were in close agreement, only PFL 1 (the most shoreward profile) was analyzed to decrease analysis time. Runup values reported are significant values Chapter 2 Monitoring Program 23 Jayemyesig UO Paysijqe}se SuO!}e90| (74d) a|lyoid puke (S,qO5) s}ulod joujuoo punoiy “g} aunbi4 WO > \N SS SS . = © D iS) o oD Cc ‘Cc 2 Cc So = a ~ ® 2 Qa @ & O RK SS y & 5. S : ae S GSS Sma: iS Re : = AMAAQ ns SS WQmrwddi x AA ARE HERE ERE GOMES TS (average of highest one third of the runup values). Wave runup periods also were obtained from the time series. Wave overtopping To measure and quantify wave overtopping at the St. Paul Harbor main break- water during storm wave events, a water collection container placed in the lee of the structure and flow meters were used. An open top container, approximately 12.2 m x 3mx 2.4 m (40 ft x 10 ft x 8 ft), was modified to serve as a collection box for waves overtopping the breakwater. The container was lined with metal to prevent leakage and included 20.3-cm (8-in.) pipes, extending from its base, in which flow meters were installed to determine flow rates. During the period 25 through 30 August 1994, a crew of WES personnel visited St. Paul Island to prepare a concrete slab to be used as a base for the container, to install the container, and to construct an apron from the top of the container up the breakwater slope. Heavy equipment was rented from the City of St. Paul. A 20.3-cm (8-in.) reinforced concrete slab was initially constructed in the lee of the breakwater (sta 8+20 - 8+60). The open top container then was placed on the slab and anchored into position with chains. An apron extending from the top of the container up the slope of the breakwater then was constructed to direct overtopping volumes into the container. The apron consisted of 10.2 cm x 10.2 cm (4 in. x 4 in.) wooden frames and bracing with a metal skin attached to the framing. A view of the completed container setup is shown in Figure 19. To measure overtopping rates, ultrasonic flow transducers were mounted to the 3.1-cm (8-in.) pipe at the base of the container and connected to a recorder (Fig- ure 20). By knowing the water level in the container at the beginning and end of a Figure 19. View of collection box used for measurement of wave overtopping Chapter 2 Monitoring Program 25 26 Figure 20. Flow transducers and recorder used to determine overtopping rates test series, and the volume of water flowing through the outlet pipe over a certain time period, the overtopping rates may be calculated. The first storm of the 1994-95 winter season that produced overtopping of the main breakwater occurred on 3 November 1994. WES personnel were onsite to measure these rates. Data were collected from 10:00 a.m. to 1:00 p.m. Massive overtopping of the structure occurred (Figure 21), and it is estimated that approxi- mately 50 percent of the overtopping waves were not collected due to spray and waves "overshooting" the container. During the storm the apron extending from the top of the container up the slope of the breakwater collapsed, as shown in Figure 22. Before the storm system subsided, the forces of the overtopping waves caused the anchors to pull out of the concrete slab. The container tilted forward (shoreward), bending the pipes used to measure the flow rates. Due to logistical problems, it was not feasible to repair the container. Therefore, data obtained initially on 3 Novem- ber 1994 were the extent of the wave overtopping obtained during the monitoring effort. Bathymetry Bathymetric data in and adjacent to St. Paul Harbor had been obtained in September 1986 (prior to construction of breakwater improvements) and again in August 1992 (after breakwater construction). These pre- and post-construction data were analyzed to determine the impact of the improvements on bathymetric condi- tions in and adjacent to the harbor. An additional bathymetric survey was com- pleted in July 1995 as part of the monitoring program. This survey was analyzed Chapter 2 Monitoring Program Figure 21. Massive overtopping of St. Paul Harbor main breakwater on 3 November 1994 Figure 22. Collapsed apron resulting from 3 November 1994 storm Chapter 2 Monitoring Program 27 28 to determine if bathymetric conditions had stabilized as a result of breakwater construction. Broken armor unit surveys A survey of broken/cracked armor stone above the waterline on the 320-m-long (1,050-ft-long) St. Paul Harbor outer main breakwater was conducted four times during the monitoring period. Surveys were conducted in July 1993, June 1994, June 1995, and June 1996. During the inspections, each broken armor stone was identified and photographed, and its approximate location relative to breakwater station and distance from a baseline was recorded. The baseline was the approxi- mate centerline of the structure. Armor stones with hairline cracks were not counted; only those that were cracked all the way through. A geological assessment of the broken stone was conducted during the June 1995 survey. Photogrammetric surveys Photogrammetric surveys, as well as ground surveys for control, were conducted during May 1994 and May 1996. To establish control for the photogrammetric work, monuments were established on the breakwater. Ground surveys were initi- ated from existing known monuments, which included National Geodetic Survey stations and a Corps of Engineers station. They were established by GPS control and electronic land surveying techniques. In addition, targets were established at intervals of about 55 m (180 ft) along the sea side, harbor side, and approximate center of the breakwater. Each target was marked with a drill hole 0.64 cm (1/4 in.) in diameter, and 0.64 cm (1/4 in.) deep, and painted with a circular target to ensure visibility in aerial photography. A typical target is shown in Figure 23. Targets were electronically surveyed to form control by which the accuracy of the photo- grammetric survey work could be validated. Horizontal positions were based on the Alaska State Plane Coordinate System and elevations were referenced to mean lower low water datum. Aerial photography is a very effective means of capturing images of large areas for later analysis, study, visual comparison to previous or subsequent photography, or measurement and mapping. Its chief attribute is the ability to freeze a moment in time, while capturing extensive detail. Low-altitude aerial photography was obtained along the breakwater with a Wild RC-8 aerial mapping camera (22.9-cm by 22.9-cm (9-in. by 9-in.) format). The photos were secured from a helicopter flying at an altitude of 91 m (300 ft), which resulted in high-resolution images and contact prints with scales of 1:600. Photographic stereo pairs were obtained during the flights. When aerial photography is planned and conducted so that each photo image overlaps the next by 60 percent or more, the two photographs comprising the overlap area can be positioned under an instrument called a stereoscope and viewed in extremely sharp three-dimensional detail. If properly selected survey points on Chapter 2 Monitoring Program Figure 23. Example of target established on St. Paul breakwater the ground have previously been targeted and are visible in the overlapping photo- graphy, very accurate measurements of any point appearing in the photographs can be obtained. This technique is called photogrammetry. The low-altitude stereo pair images obtained during aerial photography at St. Paul Harbor were viewed in a stereoscope and stereomodels were oriented to the monument and target data pre- viously obtained. In the stereomodel, very accurate horizontal and vertical mea- surements can be made of any point on any armor stone appearing in the print. The stereomodel was used for all photogrammetric compilation and development of orthophotography. Orthophotos combine the image characteristics of a photograph with the geom- etric qualities of a map. The digital orthophoto is created by scanning an aerial photograph with a precision imaging scanner. The scanned data file is digitally rectified to an orthographic projection by processing each image pixel. Orthophotos were prepared for the St. Paul Harbor main breakwater. Precise horizontal measure- ments may be obtained from the orthophotos using an engineer scale since the image has been rectified and is free from skewness and distortion. In addition to digital orthophotos, point plot maps, contour maps, and cross sections were developed for the main breakwater using the digital terrain model (DTM). Point plot maps consisted of an approximately 0.5-m (1.5-ft) grid pattern overlaid on the structure. Precise vertical and horizontal measurements were obtained at the intersections of the grid. Contour maps of the breakwater, developed from the DTM, for a 0.3-m (1-ft) contour interval also were obtained. In addition, using the analytical stereoplotter and DTM grid, cross sections were developed along the breakwater at 30.5-m (100-ft) intervals. Chapter 2 Monitoring Program 29 30 Data Results and Discussion The loss of the two DWGs placed outside the harbor significantly reduced the value of some of the other data obtained during the monitoring effort. The DWGs were deployed to obtain incident wave data that were required for correlation with wave heights inside the harbor, wave runup, and wave overtopping data. Since incident wave data were not obtained, these elements of the monitoring effort could not be validated or verified based on the physical modeling and/or numerical tools used in their predictions. When working in an environment with a high-energy wave climate like St. Paul Harbor, extra precautions should be taken to ensure that data are collected. More appropriate anchoring of the gauge mounts and/or devices hard-wired to shore to obtain real-time data should be considered. Additional costs will be required, of course, and should be included when estimates for the monitoring program are prepared. In addition, when working at a remote site such as St. Paul Harbor, logistical problems are a factor. Equipment and supplies must be shipped and, in most cases, delivery times are uncertain. Shipping costs also are significantly higher when working in a remote environment, and equipment and materials are not readily available. Wave height data obtained inside the harbor in the lee of the main breakwater are presented in Table 2. Gauge No. 276 was closest to the harbor entrance tied to the Unisea’s bow, and gauge No. 277 was tied to the vessel's stern. Maximum signifi- cant wave heights obtained during the period of record were 0.58 m (1.9 ft). Even though a correlation cannot be made with incident incoming wave characteristics, it is known that storms occurred during the monitoring period. In the three- dimensional model investigation of St. Paul Harbor, a range of extreme storm wave conditions were tested from several directions with maximum significant wave heights of 0.79 m (2.6 ft) predicted in the lee of the breakwater. Direct correlations cannot be made for specific incident waves; however, it appears the prototype and model data are in agreement. Model wave heights are slightly higher than those in the prototype, but the prototype may not have experienced an extreme storm from as critical a direction as the events tested in the model. Results of the wave hindcast model are presented in Table 3 for the dates and times indicated. Output was generated to correlate with the dates and times that wave runup and overtopping were obtained. Wave hindcast results revealed maximum significant incident wave heights of 5 m (16.4 ft). Data indicated that storms with wave heights in excess of 3 m (10 ft) occurred on 11-12 November, 14-15 November, 25-26 November, and 10 December 1994. Initial results revealed that trends were established in that larger waves generally occurred with higher wave runup values and smaller waves occurred with lower runup. The absolute values of the wave heights, however, appeared low. These values will be discussed in more detail after presentation of wave runup and overtopping results. Wave runup data secured for the St. Paul Harbor main breakwater, using the videotape methodology developed, are presented in Table 4 for the times and dates Chapter 2 Monitoring Program indicated. Wave runup values in excess of 6.1 m (20 ft) occurred on 15 occasions (19 and 22 October; 1, 2,9, 10, 12, 14, 15, 16, 23 and 26 November; and 10, 11 and 12 December 1994) during the monitoring period. Overtopping of the structure also was observed on four occasions (3, 11, 14, and 25 November 1994). Analysis of wave runup on the structure using the videotape methodology proved to be successful except during periods when visibility was low. Since incident wave data were not obtained, it was not possible to correlate runup results with those obtained in the two-dimensional model and/or those predicted by the Shore Protection Manual. Wave overtopping rates of 1.7 0/sec/m (0.022 cfs/ft) were calculated from the container in the lee of the main breakwater during the 3-hr period prior to the collapse of the container apron on 3 November 1994. As mentioned previously, as much as 50 percent of the overtopping waves were not collected due to spray and "overshooting" of the container during the storm. Therefore, the actual rates are not quantifiable. It was also noted that significant volumes of water were reaching the road as a result of waves passing through the rubble-mound structure. These values could not be quantified with the equipment setup that was onsite. Waves passing through the structure and overtopping from this storm were obviously unacceptable since they resulted in washing out of the road in the lee of the breakwater. Since incident wave conditions were not known and overtopping rates could not be quantified for this storm event, no attempt was made to correlate overtopping results with the two-dimensional model study results or guidance provided in the Shore Protection Manual. Logistical problems were experienced in the delivery of the container and materials for its apron to St. Paul Island. The container was modified, and materials for the apron were prefabricated, on the west coast of the U.S. mainland, since this work could not be done at the remote Alaskan location. These items were shipped to St. Paul Island by barge. Delivery dates to St. Paul were uncertain; however, coordination with the harbormaster resulted in the equipment being off-loaded at the harbor. Originally, plans were to design and construct the apron with a Z-beam steel frame and corrugated metal skin. Welders would have been required to assemble the apron. Since they were not available for hire at St. Paul, the decision was made to prefabricate the wooden frame and assemble it onsite. The apron was not expected to endure the entire storm season, but it was expected that data could be obtained for less severe storms. As stated earlier, it was destroyed during the first major storm of the season. These factors should be considered in future monitoring efforts in remote, high-wave-energy locations. . Measured wave runup data and observed wave overtopping were correlated with wave hindcast data. On the dates and times when runup values exceeded 6.1 m (20 ft), incident wave height data predicted by the hindcast model ranged from 0.5 to 4.8 m (1.6 to 15.7 ft). During periods of observed overtopping, hindcast wave height predictions ranged from 2.3 to 5 m (7.6 to 16.4 ft). Wave periods obtained from the hindcast model ranged from 6 to 15 sec, and those measured from video- tape ranged from 9.7 to 19.7 sec. A specific case compared was conditions on 3 November 1994, when the overtopping container apron was destroyed. Hindcast data indicated a wave height of 2.6 m (8.5 ft). Preliminary wave runup calculations Chapter 2 Monitoring Program 31 32 for 2.6-m (8.5-ft) waves indicate a runup value between 4.9 and 5.2 m (16 and 17 ft) would occur (based on Shore Protection Manual predictions); however, massive overtopping actually occurred that resulted in destruction of the apron. Local forecasts indicated winds of 50 knots and seas of 9.1 m (30 ft) on 3 November 1994. Based on these comparisons, the hindcast data appear to have under-estimated wave conditions at the site. As stated earlier, in general, trends indicated larger waves occurred with higher runup values and wave overtopping, but absolute values of the wave heights generated by the hindcast model appeared low. Bathymetric data obtained in and adjacent to the harbor in September 1986 (prior to construction of breakwater improvements) are shown in Figure 24. Note the 10.4-m (34-ft) el scour hole adjacent to the head of the breakwater. The scour hole formed after construction of the original 229-m-long (750-ft-long) breakwater in 1985. It was monitored by CENPA and did not tend to undermine the breakwater foundation. Depths adjacent to the vertical-walled, concrete caisson City Dock were dredged to greater than 6.1 m (20 ft). Though not shown in the bathymetry, CENPA noted that the cove appeared to begin filling in after initial breakwater construction with accretion along the southeast shoreline of Village Cove. At one point the connecting channel between the cove and saltwater lagoon was plugged and subsequently artificially reopened. Bathymetric data obtained in August 1992 (after breakwater improvements) are shown in Figure 25. A 10.4-m (34-ft) scour hole formed adjacent to the head of the new main breakwater extension similar to the one formed after the original break- water was constructed. The scour hole did not appear to have significantly undermined or impacted the stability of the structure head. Depths in the harbor between the northernmost dock and City Dock were greater than the 5.5-m (18-ft) authorized federal channel and maneuvering area, and therefore, dredging was not required after construction. Local interests did, however, dredge an area in the harbor adjacent to the TDX dock. Note the change in contours north of and adjacent to the detached breakwater. Sediment began accumulating against the structure. Contours of bathymetric changes that occurred between the September 1986 and the August 1992 surveys are shown in Figure 26. These contours show fill and scour conditions in and adjacent to the harbor. The figure shows a 3.7-m (12-ft) scour hole had formed adjacent to the head of the outer breakwater. In addition, accretion up to 4.3 m (14 ft) had occurred adjacent to the north side of the detached breakwater. An underwater spit had formed north of the west end of the detached structure and has the potential to migrate across the channel. Accretion of 3 m (10 ft) occurred adjacent to the south side of the detached breakwater which suggested sediment may be moving through the structure. Inside the harbor, the scour north of the TDX dock was due to dredging by local interests. Also, the scour hole formed by the original 229-m-long (750-ft-long) outer breakwater appeared to be filling. This may be due to settlement of suspended sediment caused by vessel prop wash, dredging operations, and/or hydrodynamic conditions. The August 1992 survey did not include bathymetry in the area in the lee of the east end of the detached breakwater and adjacent to the shoreline inside the harbor. Chapter 2 Monitoring Program ‘ Se POSED ae N 1,142,000 | Figure 24. Bathymetry at St. Paul Harbor, September 1986 Chapter 2 Monitoring Program NOTE: CONTOURS AND ELEVATIONS SHOWN IN FEET REFERRED TO MEAN LOWER LOW WATER (MLLW) ) ER SECONDARY BREAKWAT E 545,500, 33 NOTE: CONTOURS AND ELEVATIONS SHOWN IN FEET REFERRED TO MEAN LOWER LOW WATER (MLLW) Se Ont | Se g SECOND ——— 500, 8 3 8 m 0 3 zc oa w w Figure 25. Bathymetry at St. Paul Harbor, August 1992 34 Bathymetric data obtained during the July 1995 survey are shown in Figure 27. The scour hole that had formed at the head of the structure in the August 1992 sur- vey appears to have slightly filled in and shifted slightly west around the head of the structure. To this point, the scour hole has not impacted the stability of the head of the breakwater. The contours north of and adjacent to the detached breakwater are similar to the 1992 survey. To this point, the underwater spit has not had any negative impact on navigation. Local interests dredged an area inside the harbor Chapter 2 Monitoring Program NOTE: CONTOURS REPRESENT CHANGES IN FEET ( POSITIVE AND NEGATIVE ) BETWEEN 1986 AND 1992 SURVEYS N 1,142,500 of 9 2 a t o w N 1,142,000 | Figure 26. Contours of bathymetric changes between September 1986 and August 1992 surveys north of the West Landing. The 1995 survey extended further north of the detached breakwater and included more data inside the harbor than the previous survey. Contours of bathymetric changes that occurred between the August 1992 and July 1995 surveys are shown in Figure 28. The figure shows that the old (1992) scour hole location has filled in about 1.8 m (6 ft), with a 1.8-m (6-ft) cut at the new location to the west. The accretion immediately adjacent to the north side of the detached breakwater in 1992 had subsided by 3 m (10 ft). Not shown on the figure (due to lack of data in 1992), however, is a slight shift in the underwater spit north Chapter 2 Monitoring Program 35 R DETACHED BREAKWATER —— __DeTAL N 1,142,500 | N 1,142,000 E 545,500 =888:500 5 NOTE: CONTOURS AND ELEVATIONS SHOWN IN FEET REFERRED TO MEAN LOWER LOW WATER (MLLW) Figure 27. Bathymetry at St. Paul Harbor, July 1995 of its old location with accretion observed. Accretion of 1.8 m (6 ft) had occurred at the seaward head of the detached breakwater. Cut and fill inside the harbor north of the TDX dock was probably related to the dredging operations at West Landing by local interests. In an effort to better quantify scour and fill conditions at the harbor entrance, two areas were selected for more detailed analysis. Figure 29 presents the areas identified. Area A consists of 15,500 sq m (166,800 sq ft) and was initially used to determine scour adjacent to the head of the breakwater extension; Area B includes 11,770 sq m (125,700 sq ft) and was used to depict accretion across a portion of the entrance. Detailed bathymetry (0.3-m (1-ft) intervals) for Areas A and B are shown in Figures 30 through 32 for the 1986, 1992, and 1995 surveys, respectively; and 36 Chapter 2 Monitoring Program NOTE: CONTOURS REPRESENT CHANGES IN FEET (POSITIVE AND NEGATIVE) BETWEEN 1992 AND 1995 SURVEYS KWATER ___—_— ED BREA _peTach es N 1,142,500 + — 645,500 ° r=) SB oO + o w CONTOURS AND ELEVATIONS SHOWN IN FEET REFERRED TO MEAN LOWER LOW WATER (MLLW) WEST LANDING Figure 28. Contours of bathymetric changes between August 1992 and July 1995 surveys cross sections through Areas A and B (at locations shown in Figure 29) are presented in Figures 33 through 35 for the various surveys. Contours of bathy- metric changes that occurred between September 1986 and August 1992 are shown in Figure 36, and those occurring between August 1992 and July 1995 are presented in Figure 37. Erosion and accretion volumes were calculated for each area. Results indicate that, during the period 1986 through 1992, approximately 31,960 cu m (41,800 cu yd) of scour occurred in Area A and about 13,070 cu m (17,100 cu yd) of accretion occurred in Area B. This was the result of post-breakwater modifi- cations. Between 1992 and 1995, Area A accreted about 4,660 cu m (6,100 cu yd) and Area B accreted approximately 5,350 cu m (7,000 cu yd) of material. Net volumes (between 1986 and 1992) are 27,300 cu m (35,700 cu yd) of scour in Area A and 18,420 cu m (24,100 cu yd) of fill in Area B. Chapter 2 Monitoring Program 37 + OOS evl IN m [e) po (‘) iw ° fe) v 000'¢oi'l N sishjeue pallejap 10} pajoajas soue Ue JOQUeU Je Sealy “GZ OuNbI4 Chapter 2 Monitoring Program 38 Kanins 986} sequiejdas 40) g pue y seauy ul AjawAujyeq payiejeq ‘o¢ eunbi4 (ATNW) Y3SLVA MOT Y3MON NV3BW OL Q3¥¥3433Y 1334 N! NMOHS SYNOLNOD :3LON 39 Chapter 2 Monitoring Program Aaains 2661 Jsniny 10} g pue y seaiy ul AyjawAujyeg payejaqg “1 ¢ aunbi4 (MATIW) Y310M MOT ¥3MO1 NYV3W OL Q3¥¥3533Y 1334 NI NMOHS SYNOLNOD *2LON Chapter 2 Monitoring Program 40 41 Aaanins S66 lt Aing 40) g pue yy seouy ul AyjowAujeg payrejeq ‘ze ani (MMW) HALYAA MOT YaMO71 NVAW OL G3HH343Y 1334 NI NMOHS SNOILVA313 GNV SHNOLNOD ‘3LON Chapter 2 Monitoring Program SECTION A-A e uw Ww iL z z fe) < > iy =I w 300 400 500 600 700 DISTANCE IN FEET —— 198 SURVEY — — 1992 SURVEY -—-—— 1995 SURVEY Figure 33. Cross sections through Area A, Section A-A for 1986, 1992, and 1995 surveys SECTION B-B ELEVATION IN FEET 500 200 300 DISTANCE IN FEET —— 1986SURVEY — — 1992SURVEY ———— 1995 SURVEY Figure 34. Cross sections through Area B, Section B-B for 1986, 1992, and 1995 surveys The July 1995 survey was more comprehensive than the August 1992 survey in that it included more bathymetry inside the harbor. To determine changes as a result of the opening between the detached breakwater and the shoreline, the July 1995 survey was compared to pre-breakwater conditions (September 1986 survey). Contours of bathymetric changes in the lee of the eastern portion of the detached breakwater were prepared. Data indicate accretion of 2.4 m (8 ft) in areas inside the harbor between 1986 and 1995, as shown in Figure 38. In summary, since construction of breakwater improvements at St. Paul Harbor, a scour hole initially formed at the head of the main breakwater extension similar to the one at the head of the structure prior to improvements. The scour hole has shifted in location somewhat, but has not undermined the toe of the breakwater head 42 Chapter 2 Monitoring Program SECTION C-C = uw uw w z z © re Ss uJ —_ uu 200 300 DISTANCE IN FEET 1986 SURVEY ———— 1992 SURVEY — --— 1995 SURVEY Figure 35. Cross sections through Area A, Section C-C for 1986, 1992, and 1995 surveys or impacted the structure's stability. An accumulation of sediment has developed north of and adjacent to the detached breakwater with an underwater spit migrating toward the entrance channel. The underwater spit also has shifted in location somewhat, but no navigational difficulties have been experienced to this point. Inside the harbor, an accumulation has occurred due to material moving in between the east end of the detached breakwater and the shoreline. This material, however, is not depositing in the navigation channel or mooring areas. Results of the three-dimensional model investigation predicted shoaling patterns precisely at St. Paul Harbor. The fixed-bed model could not be used to quantify the volume of sediment moving in the area, but could qualitatively predict sediment patterns and areas of accumulation. The model indicated sediment would accumu- late north of and adjacent to the detached breakwater and migrate toward the entrance channel. It also indicated sediment would move into the harbor between the detached breakwater and the shoreline, but would not accumulate in the mooring areas. These predictions are shown in Figure 10. Also note that tracer material in the model was swept clean at the head of the breakwater extension, which would indicate possible scour conditions. The broken/cracked armor unit survey of the St. Paul Harbor main breakwater during July 1993 revealed a total of 73 broken or cracked armor stones above the waterline. Of the 73 stones, 7 stones were located on the crest, 31 on the seaward slope, and 35 on the harbor-side slope. In the vicinity of the northernmost dock at sta 14+30 (the seaward end of the additional layer of armor stones on the break- water), some void areas between adjacent capstones were noted. The capstones had migrated away from each other. The June 1994 survey yielded a total of 131 broken or cracked armor stones. Of these 131 units, 24 were located on the crest, 59 on the seaward slope, and 48 on the Chapter 2 Monitoring Program 43 shaAins 2661 IsNiny pue 9g6l 4equiajdes usemjeq g pue VY Seay Ul SebUeYO dIWJaWAUJeg JO SINOJUOD “gE aINbi4 (MATIW) YS3LVM MOT Y3MO7 NV3AW OL GO3y¥¥353Y 1334 NI NMOHS SYNOLNOD :31LON Chapter 2 Monitoring Program sAanins s66l Aine pue z66l. Isniny usemjeq g puke y Seay ul SabueYO oIJaWALJeQ Jo SINOJUOD “ZE auNnbi4 (MTIW) YBLVM MO7 Y3MO71 NV3AW O14 Gaud3538 1334 NI NMOHS SNOILVA313 OGNV SYNOLNOD ‘3.LON 45 Chapter 2 Monitoring Program N 1,143,000 soe + : + N 1,142,500 NOTE: CONTOURS REPRESENT CHANGE IN FEET (POSITIVE AND NEGATIVE) BETWEEN 1986 AND 1995 SURVEYS Figure 38. Contours of bathymetric changes in the lee of the eastern end of the detached breakwater between September 1986 and July 1995 46 tori Chapter 2 Monitoring Program harbor-side slope. Observations during this inspection revealed that the separated capstones identified in 1993 (sta 14+30) were in about the same position. During the broken/cracked armor unit survey of June 1995, a total of 191 broken or cracked armor stones were identified. Of the 191 stones, 35 broken/cracked armor units were located on the crest, 93 on the seaward slope, and 63 on the harbor-side slope. Several broken stones documented during previous surveys could not be found, indicating they had been moved away by wave and/or ice action. Also, it was observed that stones were missing along the water's edge on the sea- ward face of the structure at approximately stas 8+85 and 9+50. The 1994-95 winter was relatively severe with the presence of much floating ice. The voids at the waterline on the main breakwater were subsequently repaired by CENPA during the summer of 1995 using selected stones from the St. Paul Island quarry. During the 1995 survey, a detailed geologic inspection of the breakwater was conducted by representatives of the Buffalo District. These personnel had experi- ence in armor-stone quality and durability for coastal projects. Based on their analyses, 22 percent of the above-water stones are experiencing advanced degrada- tion. This degradation is attributed to two factors. First, the project contains about 25 percent geologically unacceptable stone. The unacceptable stone is a light gray, vesicular banded basalt that has a marked platy structure. This stone likely came from the Smithrock Quarry in Camas, WA. About one half of this stone contains one or more significant cracks. These cracked stones exhibit common freeze-type and/or blasting crack characteristics. The delamination process is being enhanced at the St. Paul location because of the number of cycles of freeze-thaw and wet-dry conditions as well as large waves and sea ice action. Secondly, a significant amount of the stone on the structure is blast damaged. Fracture patterns and shape charac- teristics observed on much of the stone are common in overshot rock. As observed commonly in other breakwaters, this structure is predicted to continue to deteriorate, and the degradation rate is likely to increase as time progresses at this environmen- tally harsh location. It was also predicted that future project performance would be significantly impacted in the next 3 to 7 years and repairs should be expected. During the breakwater survey of June 1996, a total of 230 broken/cracked armor stones were identified on the main breakwater. Of the 230 stones, 54 were located on the crest, 105 on the seaward slope, and 71 on the harbor-side slope. The rate of breakage was slightly less for this survey than for previous years; however, the harbor master indicated that the 1995-96 winter was milder than normal. As of the June 1996 survey, the approximate locations of broken/cracked armor stones along the outer portion of the breakwater are shown in Figure 39, and detailed data obtained during the survey are presented in Table 5. Armor stone numbers identi- fied in Figure 39 correspond to those listed in Table 5. As shown, only two broken armor units are located around the head of the structure. Armor stone for the break- water head consisted of sound and durable granite from a quarry in Nome, AK. Shoreward of the breakwater head, broken stones were, generally, evenly distributed along the length of the structure. The survey showed that 49 percent of the broken stones were located on the shoreward half of the breakwater extension, and 51 percent on the outer half. About 23 percent of the observed broken stones were along the crest, 46 percent on the seaward slope, and 31 percent on the harbor-side Chapter 2 Monitoring Program 47 48 STA 16+00 STA 15+00 STA 14+00 STA 13+00 STA 12+00 BSTA 10+00 Figure 39. Approximate locations of broken/cracked armor stone on outer breakwater during June 1996 survey Chapter 2 Monitoring Program slope. The survey also showed that 50 percent of the broken stones were located on the upper half of the breakwater slopes (27 percent on the sea side and 23 percent on the harbor side); and 27 percent were on the lower half of the structure slopes (18 percent on the sea side and 9 percent on the harbor side). Views of representa- tive types of breaks for the armor stones are shown in Figures 40 through 43. Armor stones with hairline cracks on one side were not counted; only those that were cracked all the way through were considered a break for recording purposes. It was noted during the June 1996 survey that the separated capstones at sta 14+30, initially observed in July 1993, were about in the same position. Overall, the St. Paul Harbor main breakwater appears to be functional and in good condition. Prior to the photogrammetric survey work for the St. Paul Harbor main break water, limited ground surveys were conducted. Monuments and targets established on the breakwater are shown in Figures 44 and 45 for the May 1994 and May 1996 surveys, respectively. Positions and elevations of the monuments/targets are pre- sented in Table 6 for the two surveys. Although slight movement may have occurred between 1994 and 1996, the 1994 control points were used for truthing during the 1994 photogrammetric flight and the 1996 control points for the 1996 photogrammetric flight. In some cases, targets were re-established. An example of photographic stereo pairs secured for the breakwater is shown in Figure 46. After orientation in the stereomodel to the monument and document data previously obtained, orthophotos were developed. Accuracy of photogrammetric spot elevations was on the order of +9 cm (+-0.03 ft). Figure 47 is a typical ortho- photo for a portion of the breakwater. In addition, point plot maps were developed for the breakwater for the 1994 and 1996 surveys. An example of a point plot map showing elevations on the structure is shown in Figure 48. Areas where no eleva- tions are shown are shadowed areas, or voids between the armor stones. Contour maps of the breakwater were developed from the DTM for the 1994 and 1996 surveys. Topography of the breakwater in 1996 is shown in Appendix A. Contours depicting the difference in elevations of the breakwater between 1994 and 1996 are shown in Appendix B, and cross sections of the breakwater in 1994 and 1996 are shown in Appendix C. An examination of the breakwater topography for 1996 (Appendix A) reveals low areas along much of the breakwater. Only about 5 percent of the higher portion of the structure (sta 7+50 - 15+10) is at its design el of +11.3 m (+37 ft), and 9 per- cent of the lower portion of the breakwater (sta 15+10 - 18+00) is at its design el of +9.1 m (+30 ft). For the higher portion of the structure, the el of about 24 percent of the length of the breakwater is within 0.3 m (1.0 ft) of its design el, or between +11.0 and +11.3 m (+36 and +37 ft); and approximately 66 percent of the structure is between +11.0 and +11.3 m (+35 and +37 ft), or within 0.61 m (2 ft) of its design el. About 29 percent of the structure length is below +10.7 m (+35 ft). Most of the low area (that below +10.7 m (+35 ft)) appears to be concentrated between stas 13+70 and 15+10. For the lower portion of the structure, the el of about 50 percent of the length of the breakwater is within 0.3 m (1.0 ft) of its design el, or between +8.8 and +9.1 m (+29 and +30 ft); and approximately 89 percent of the structure is within 0.61 m (2.0 ft) of its design el, or between +8.5 and +9.1 m (+28 and +30 ft). Only 2 percent of the structure length is below +8.5 m (+28 ft). Chapter 2 Monitoring Program 49 Figure 40. View of broken armor stone on St. Paul Harbor breakwater (station 10+21) Figure 41. View of broken armor stone on St. Paul Harbor breakwater (station 11+78) Contours showing the difference in elevation of the St. Paul Harbor breakwater extension from 1994 to 1996 (Appendix B) reveal very slight change. Results indicate essentially no change along the crown of the structure. In the vicinity of sta 9+50, a change up to 0.9 m (3 ft) occurred along the waterline on the sea side of 50 Chapter 2 Monitoring Program Figure 42. View of broken armor stone on St. Paul Harbor breakwater (station 11+87) Figure 43. View of broken armor stone on St. Paul Harbor breakwater (station 17+34) the structure. This was one of the areas, however, where emergency repairs were made in 1995 following the broken armor stone survey. Other changes (between 0.3 and 0.9 m(1 and 3 ft)) generally occurred on the harbor side of the breakwater. These data indicate no settlement of the structure between 1994 and 1995. 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R iy ot Ss Wa » SS sy .* Soon : may Ay Ness GN . a NE aes a’ ; ea aon ; wt wows Se ‘ee? eh yw e w* oS av? Xe ‘vo’ “ay ev? we §\ ter . yt oe aN e yoy wt} ¢ tt a) a Seeks wee w Ns we 55 Ch apter 2 Monitoring Pr ogram 56 Examination of the data in Appendix C reveals that cross sections of the break- water were similar in both 1994 and 1996. Accretion of stone along the toe of the harbor-side slope of the structure is shown at stas 11+00, 12+00, and 13+00. This was an accumulation of small stones which were noted during the 1996 broken armor stone survey. CENPA personnel inspected the breakwater in November 1996 after a large storm and determined the small stones coming out of the structure were chinking stone used during breakwater construction. Approximately a 1.8-m (6-ft) layer of this small stone was placed directly under the armor layer during construction. In summary, the photogrammetric surveys of the St. Paul Harbor breakwater extension were very effective in accurately mapping the above-water portion of the structure and showing changes in el occurring from 1994 to 1996. Results indicated that low areas existed along the length of the breakwater. The higher portion of the breakwater extension seaward of the roadway was at least 0.61 m (2 ft) below its design el over 29 percent of the length of the structure. Only 5 percent of the break- water length was at, or above, its design el. This could contribute to the undesirable overtopping of the breakwater being experienced. As stated earlier, quantifiable overtopping rates were not obtained during the monitoring effort. However, it would have been difficult to correlate them with the two-dimensional model results had they been secured. The elevation of most of the prototype breakwater in this vicinity is below its +11.3-m (+37-ft) design, and the el of the structure tested in, and recommended by, the model was +11.9 m (+39 ft). For the outer portion of the breakwater extension, 9 percent of the structure length is at, or above, its design el of +9.1 m (+30 ft), with 98 percent within 0.61 m (2 ft) of its design el. The break- water extension may have subsided after initial construction, causing the lower- than-design elevations; however, essentially no change in el occurred between 1994 and 1996 based on results of the photogrammetric analysis. Chapter 2 Monitoring Program 3 Conclusions and Recommendations Conclusions Failure to obtain incident wave data outside the harbor had a negative impact on analysis of some of the other data collected during the monitoring effort. Incident wave data were required for correlation with wave data obtained inside the harbor, wave runup, and wave overtopping data to validate design methods and procedures. Wave height data obtained inside the harbor (from the Unisea vessel) appeared to validate the three-dimensional model study. Maximum significant wave heights measured in the immediate lee of the main breakwater during storm wave events were in agreement with those predicted during the physical model study. The videotape analysis used to obtain wave runup data along the face of the St. Paul Harbor main breakwater was successful, except during periods of low visibility. The technique is relatively low cost, logistically simple, and provides relatively accurate measurements. Trends in wave hindcast data obtained outside the harbor (to define incident wave conditions) correlated reasonably well with runup data in a qualitative sense (i.e. larger wave heights correlated with higher runup and smaller wave heights with low runup). The absolute values of the hindcast significant wave heights, however, appeared to be substantially lower than the waves experienced in the prototype based on runup values measured, overtopping observed, and local forecasts. Since construction of breakwater improvements, a scour hole has formed at the head of the main breakwater extension, sediment has accumulated north of and adjacent to the detached breakwater (forming an underwater spit that is migrating toward the entrance channel), and sediment has moved into the harbor between the detached breakwater and the shoreline. To this point, the scour hole has not impacted the structure's stability, nor has the underwater spit interfered with navigation. Accretion inside the harbor has not occurred in the federal channel or mooring areas. Sediment patterns in the harbor, as predicted by the three- dimensional model, were validated by the prototype data. Chapter 3 Conclusions and Recommendations 57 58 The St. Paul Harbor main breakwater is currently functioning in an acceptable manner and is in good condition structurally; however, the armor stone continues to degrade. The number of broken/cracked armor stones on the 320-m-long (1,050-ft- long) breakwater extension increased from 73 in July 1993 to 230 in June 1996. A geologic assessment indicated that about 25 percent of the original stone placed was geologically unacceptable, and a significant amount of the stone on the structure was blast damaged. Continued deterioration is predicted due to freeze-thaw and wet-dry cycles as well as large waves and sea ice action. Photogrammetric analysis of the St. Paul Harbor main breakwater proved to be an excellent tool in mapping the above-water portion of the structure extension and quantifying changes in elevation. Results revealed most of the breakwater extension was below its design elevation. Almost a third of the higher portion of the break- water seaward of the harbor roadway was at least 0.61 m (2 ft) below its design el of +11.3 m (+37 ft). Analysis also indicated essentially no change in el of the breakwater crown between 1994 and 1996. Recommendations Extra precautions should be taken when monitoring future projects in extremely high-wave-energy environments to ensure that required data are obtained. The loss of the prototype wave gauges and the destruction of the wave overtopping container reduced the value of the monitoring effort at St. Paul Harbor. In the future, in-depth research of conditions should be conducted to assure success. When monitoring projects in remote areas, logistical problems may be experi- enced. Delivery dates and/or availability of equipment, supplies, materials, etc. are uncertain. These problems should be considered during the development of future monitoring plans in remote locations. Additional time and costs associated with these problems also should be considered. The St. Paul Harbor main breakwater should be observed very closely due to the continued degradation of armor stone on the structure. Preparatory work for repair considerations should be initiated since the deterioration rate is not expected to decrease. When repair or rehabilitation occurs, the highest grade of geologically acceptable stone should be placed above the waterline. Inspection of 100 percent of shot stone for near-invisible hairline blast fractures also should be conducted by skilled personnel. Only the most sound and durable stone should be used in this extremely harsh environment. Chapter 3 Conclusions and Recommendations References References Bottin, R. R., Jr., and Mize, M.G. (1988). “St. Paul Harbor, St. Paul Island, Alaska, design for wave and shoaling protection; hydraulic model investigation,” Technical Report CERC-88-13, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Ebersole, B. A. (1985). “Refractional-diffraction model for linear water waves,” Journal of Waterway, Port, Coastal, and Ocean Engineering, American Society of Civil Engineers, New York, III (6), 985-999. Hathaway, K., Howd, P., and Oltman-Shay, J. “Infragravity waves in the nearshore zone,” in preparation, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Howell, G. L. (1993). “Design of an in-situ directional wave gage for one year deployments.” WAVES ’93, Proceedings of the Second International Symposium on Ocean Wave Measurement and Analysis. American Society of Civil Engineers, New York, 264-276. Hubertz, J. M. (1992). “User's guide to Wave Information Studies (WIS) wave model, Version 2.0,” WIS Report 27, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. Noda, E. K. (1972). “Equilibrium beach profile scale-model relationship,” Journal, Waterways, Harbors, and Coastal Engineering Division, American Society of Civil Engineers, New York, 98 (WW4), 511-528. Shore protection manual. (1984). 4th ed., 2 Vol, U.S. Army Engineer Waterways Experiment Station, U.S. Government Printing Office, Washington, DC. Tetra Tech, Inc. (1987). “St. Paul Harbor and breakwater technical design report,” TC-3263-07, Pasadena, CA; prepared for the City of St. Paul, Alaska. U.S. Army Engineer District, Alaska. (1981). “St. Paul Island, Alaska; harbor feasibility report,” Anchorage, AK. 59 60 Ward, D. L. (1988). “St. Paul Harbor breakwater stability study, St. Paul, Alaska; Hydraulic Model Investigation,” Technical Report CERC-88-10, U.S. Army Engineer Waterways Experiment Station, Vicksburg, MS. References Table 1 MCNP Program Areas of Interest Shoreline and nearshore current response to coastal structures Wave transmission by overtopping Prediction of the controlling cross section at inlet navigation channels Wave attenuation by breakwaters (submerged and floating) Bypassing at jettied and unjettied inlets Wave refraction and steepening by currents Beach fill project monitoring Stability of rubble structures - investigations to determine causes of failure Comparison of pre- and post-construction sediment budgets Wave and current effects on navigation Dynamics of floating structures Wave reflection Effects of construction techniques on scour and deposition near coastal structures Diffraction around prototype structures Wave runup on structures Onshore/offshore sediment movement near coastal structures Harbor oscillations Wave transmission through structures Material life cycle Ice effects on structures and beaches Model study verification Wave translation Construction techniques Table 2 Significant Wave Hei Observation Date and Time Date hts and Peak Periods from Unisea Data Limi | pat Gauge Number 276 H, m (ft) 0.15 (0.5) T, (sec) 5 Sep 94 10.7 = 5 Sep 94 6 Sep 94 6 Sep 94 13 Sep 94 13 Sep 94 0.30 (1.0) 0.34 (1.1) 2a oe jozr os) 0.27 (0.9) 13 Sep 94 13 Sep 94 0.37 (1.2) 14 Sep 94 14 Sep 94 0.24 (0.8) 14 Sep 94 14 Sep 94 0.18 (0.6) 14 Sep 94 14 Sep 94 0.15 (0.5) 14 Sep 94 14 Sep 94 0.15 (0.5) = 15 Sep 94 0114 15 Sep 94 0217 0316 0.15 (0.5) 16 Sep 94 0.09 (0.3) 1 Oct 94 0.12 (0.4) 0.09 (0.3) 0.09 (0.3) EERE EER EER ERE EEE 0.15 (0.5) 0.12 (0.4) HE 0.21 (0.7) i £1 10.2 0.21 (0.7) ii 10.2 0.21 (0.7) g elgle 10.2 0.18 (0.6) e £ 10.2 0.21 (0.7) Sheet 1 of 4 Table 2 (Continued Observation Date and Time Gauge Number 277 Date timel | | T, (sec) T, (sec) H, m (ft) 102 foowe | 102 [roe | 102 Dec 177 rpecse [ous | 177 Dec 177 Dec : ee a|s\s Palka eaenre o j= ue g 22 i £ g © R 134 jors os) | 128 ee ee ee ee jreoecee | ram | to7_ ors os) | jredecoe [ror | 107 ors os) | ji7pece | zo | as oo os) | jredecee | 1505 | ns | cco (oa) | jrepece foo | o7_ fore ow | hn on en ee ee Ein er EE eS BSS eT Eee a ee (etoscosital fossa Wi |/iie | ateresn | | a ean Sheet 2 of 4 Slelelsleleis Sie 1s Fe 1s gs elelelelelele a 8 ~) rs : Table 2 (Continued Observation Date and Time Gauge Number 276 Gauge Number 277 H, m (ft) T, (sec) H, m (ft) 0.09 (0.3) 8 0.18 (0.6) 0.18 (0.6) ocean 0.15 (0.5) 0.15 (0.5) _ = o 0.21 (0.7) 0.18 (0.6) 0.18 (0.6) 0.21 (0.7) 0.12 (0.4) 0.12 (0.4) 8 e 8 fo] 8 0.12 (0.4) 0.15 (0.5) 0.12 (0.4) 8 & 8 B a 0.12 (0.4) 0.12 (0.4) 0.15 (0.5) 0.43 (1.4) 0.15 (0.5) 0.18 (0.6) 0.15 (0.5) 8 § = Le) N a oO 0.21 (0.7) 0.18 (0.6) 0.21 (0.7) 0.18 (0.6) 0.15 (0.5) 0.18 (0.6) 0.15 (0.5) 0.24 (0.8) 0.15 (0.5) ‘Sheet 3 of 4 Table 2 (Concluded Observation Dato and Time Date Tp (see) 2a no pace eT ee ees) ee esa aa fereieo | [isSacronl Cenae « CC see | Beas esieo | pam learn am oises) «| Se oe ae Sees Fee ae es Cs ce eS eee ae eee ee ee ee Ee Ss es oa Paes ee coca ee foe oe eS ee ova [aEINGO ee eee ee [10 Apres | osso [Rima Rosie (te jis rerss [ows [ize [oom | jranorss [ose [ns foaray | fra veras [ie [or foam | jiaaees [rs [ror fearon | jw sores for [7 forsee) [| wanes oro | os forse | jis aerss [oc [sors | lazverss [sss |e footy | ed ee re rpres [120 | 107 __| 009 09) ‘Sheet 4 of 4 Table 3 Significant Wave Heights and Peak Periods from Hindcast Data WIS Model Result ae Cee A ee ee a ae ee ee ize ym teas = Yer a Sco touts [cestode [ieee 2 [acne oh osha eee eat Fes Sateen 0.91 (3.0) [steep 2 119 89) 22 Oct 94 fen 23 Oct 94 0.30 (1.0) 1829 1733 1700 1022 1800 23 Oct 94 25 Oct 94 25 Oct 94 1711 : 1730 1039 1409 ae es faworee | hee eae ees ERE Ee 4 Nov 94 1207 Sheet 1 of 3 Observation Date and Time Date = 8 4 Nov 94 = = 9 Nov 94 10 Nov 94 10 Nov 94 11 Nov 94 11 Nov 94 12 Nov 94 1147 3 % 12 Nov 94 13 Nov 94 13 Nov 94 14 Nov 94 14 Nov 94 15 Nov 94 1222 15 Nov 94 17 16 Nov 94 1121 7 _ N 16 Nov 94 17 Nov 94 17 Nov 94 1812 a ee Leroy sane ee ER aa neal ey Ree Sheet 2 of 3 18 Nov 94 1013 18 Nov 94 19 Nov 94 19 Nov 94 20 Nov 94 3 20 Nov 94 21 Nov 94 Si 8 21 Nov 94 22 Nov 94 22 Nov 94 23 Nov 94 S aie ae eo cece) Seer oan es co eee lea Cet. tenon lee snore ag eae een een ee aces lew tity ee a Ge Smee ee Elia eee ne cm aa oe ee oes em Ge iti ere we ie ee [pe icin eo nee Cem Ree ee (0m ieee ie a EN eas Se rea Ge ee iene Be ice a eo Meomohicm lio ese tim a oe fo ii oe oe inhi hoc Table 4 Wave Runup Data Secured with Videotape Analysis Observation Date and Time [ial cern 17 Oct 94 negligible runup 17 Oct 94 negligible runup 18 Oct 94 negligible runup 18 Oct 94 raining, targets not visible 19 Oct 94 19 Oct 94 20 Oct 94 negligible runup 20 Oct 94 negligible runup 21 Oct 94 negligible runup 21 Oct 94 negligible runup 22 Oct 94 22 Oct 94 23 Oct 94 23 Oct 94 foggy, targets not visible 25 Oct 94 negligible runup 25 Oct 94 negligible runup 26 Oct 94 negligible runup 26 Oct 94 negligible runup 28 Oct 94 foggy, targets not visible 28 Oct 94 negligible runup 1 Nov 94 1 Nov 94 fenoves [ree | |_| ranng targets not vi | fanoves [rae | |_| vertopping, toocark | Les i es eee Sheet 1 of 3 Table 4 (Continued ae eSiT 3 Date T, (sec) m (ft) ee | 13.54 (44.4) | overtopping ae ies Ee es I eeeslece bere eo Im Ie! Ee ies eo een cic ls a eo ins le fees fe a ee fran ie a a Ce ai ai ace co foots a (eel Sta ae en ee ee ee oo a hat Salsa a) eo el ana aa iw Ne | oo ella By aus on JS A aa aa Cera en ae ee Sheet 2 of 3 Table 4 (Concluded Observation Date and Time Profile 1 Runup el m (ft) Date T, (sec) Comments 23 Nov 94 17 2.73 (24.5) 24 Nov 94 too dark, targets not visible 24 Nov 94 5.07 (16.6) 25 Nov 94 1111 15.1 13.06 (43.0) | overtopping 13.42 (44.0) | overtopping 26 Nov 94 9.26 (30.4) 26 Nov 94 12.8 5.40 (17.7) 27 Nov 94 3.26 (10.7) o NX 27 Nov 94 3.69 (12.1) 28 Nov 94 negligible runup 28 Nov 94 negligible runup = 29 Nov 94 1 negligible runup 4 Dec 94 negligible runup 5 Dec 94 1735 negligible runup 6 Dec 94 negligible runup 6 Dec 94 negligible runup 8 Dec 94 jeveces [ious | ee ee ee regi runp jtopecsa ie ze | orem | ee i eas ee a ee ee filer esos [lens Wp Pema Po jrepeces [amos ee | savon| ([Etisterat ris Saceceee ne ee I EE 10.9 5.71 (18.7) 5.32 (17.5) Table 5 Broken Armor Stone Inventory as of June 1996 Distance from Baseline Distance from Baseline m (ft) m (ft) oe pone Harbor Side ee eee ee ee ee a Eee ee Ee ee ee Cae Eanes ee ee ee Ee a Cee ee ee ee Ee ee 2 ee a eee ee : en 700 | ae | = sere e+13 187 (48 i 7 7 © © + = to) +0 7.9 (26) 9+22 7+97 7+99 = eee ioe 9+28 eet | 7.6 (25) sas [wig 70 (23) jeer fe | = ae ee ee ee eee ee es 2.1 (7) 9+22 12 14 8+29 =_ @ & 9.5 (31) 11.3 (37) 10.1 (33) oo fo) Qo fos) oo 0 VI 131812 12 Ls) = (>) ie) 18 (6) 12.2 (40) 18 (6) Sheet 1 of 4 Table 5 (Continued Distance from Baseline Distance from Baseline m (ft) m (ft) ee Cee peer > Je ee a ae ear si |S 0d ee ee eT an (el ieee ee =n (ey Sule ne ee eee 2 le tere Une le leo co, (i en ee oe a ee =o |e cle en 1 ee ie =o [eee =o (Cen Pe “ne EI | = Sa SE EE sa) se ene | Ree “cP EN | ES Ee Fe ae “ne oe ee Beton aa chisel et ae | ore Table 5 (Continued Distance from Baseline Distance from Baseline m (ft) m (ft) Station Stone No. Harbor Side || Station Harbor Side a aE iene ean FE A TT riicin etic ciel ao rican Paes ene ee a (eT Misr ie ee | ni rr et Go ss iii ici io 0 a few fw fnew [I a a kes) coches Eee Cea 14423 a6 sulin 6.1 (22) genus Ee ae ee ee ee ae ie ee Sheet 3 of 4 Table 5 (Concluded Se i ol m (ft) m (ft) a eae] ee ete] 0.3 (1) 4.6 (15) ft ecco eee | Faia | esr fe ae eae a ee 15472 16154 Le] Be oS a ees ee i a ee anion ema eciesmnt pd 1578 | 187 jisiso | a Ee Reese Soa Sean ae : oc Gm hae el 7.6 (25) [i cere | 8 15+91 7.6 (25) 15+91 © DN) o N 8 a N i i 8 LPs resin | [co ssi | ae [moc] ie 2 2 2 2 2 2 10.7 (35) 2 2 Ee ee | 76.05) | Ne SS CI | ict er eat Sia g a y & fos) oe) 8 = ul Bie resis | 40 1s) | [67 a) fanart 2 ir weaytecbory 10.7 (35) 11.9 (39) ih tas iia ea [21 eo) | ssrceiend 3 jst oy | CE esa) CTs Gaeta a ee 97 a) ig iowa) Pe [104 co) _| Se ae Sheet 4 of 4 07 11 13 14 16 17 18 19 224 225 226 227 Table 6 Positions and Elevations of Monuments/Targets Used for Control for 1994 and 1996 Photogrammetric Surveys Fs Pd Target : : m (ft Target g g m(ft Js | sasszor | rsaszosse | aoer coon | sassa07 | ssasaosse | 2047 67 _| 2 | nvazeso.o | rsesteoes | asercisie 12 | rrazesoso | issareoas | 21 c5.6)_| ma | rv4zeo175 | rsestzoee | asvacison 10x | r14zeon77 | iseor2070 | 405 (408) _| 4 | ssaasoras | rsssznees | sococrasa «| rsazsor.so | rsescoses | 40st a2) | me ___| sr4assez77 | rssatree7 | 42cecise0 foe | 14250676 | ssearse7e | ate0 (19:74) ef reeenss [sess | 2016 am fe __| svazasara | rseszzeas | soreco2s eo | rvszasae | rseszzese | eore co2s)_| nao | srazuzees | rssar7072 | 2ase (eos) |ltoor | r14auar.z0 | sssarze25 | 2000 27 jo srazaszoa | isssareus | s7secrea lio | s1azzezas | ssesaraao | 5750 (1909) _ mit | srazerras | rssszeaas | rose oon im | ss4zerr.e | rseazes.00 | roan (2290) 2 | rrazese.2e | rseszsese | sore coon ra | srazaso.ze | reeazas.ne | ore (990) aia | sraaras.as | resssoee | seoecrie9 |rraR | ssazrar.o | resaaoo.10 | ase6 (1.40) Mi | stezrisze | rssssue2 | rosoe ase rm | riazrises | isosouean | ron7 (2549) nate | rrerose.ss | rseauise7 | ssorcrose | i6r | sratosa. | resaaso.18 | 4012 (15.19) Miz | steroueze | rsssari2e | rossr (asa |__| rvaroaoa | ssoaars.re | soos (2555) nase | ssareores | rsessz047 | sero c2on |vier | var7e075 | sseasaste | ae0 12.70) jo | ssar7e025 | rsssaros0 | r1on9(510 20 | rv4r7e025 | ssoareo | 11.009 (26.10) nazi | sarzsro1 | rssausoe | 2054 (on rae | s1ar7607 | rseausaas | 9767 1296) naze | s1aresa2 | rseaso2ss | aerociesn |lv22R | rvarean2e | ssnasosea | aces (1500) 2s | ssaetaze | sssasaa07 | 10051 (560) [m2 | ssarseear | rssssss02 | sa77iio2e 12s | rrar4seo | sseseseo7 | sera 9.27 js | ssarast.ce | sseasao.er | 11.424 07.49) | jar ssaraanon | seeasraca | aati Nae | | (oi emaeic , 1141307.94 | 158374795 | 5.861 (19.23) 1141296.86 | 1583715.06 | 8.214 (26.95 3.414 (11.20) 1141413.01 | 1583575.63 3.414 (11.20) 1141317.83 | 1583772: 5.078 (16.66) 1141296.86 | 1583715.06 8.214 (26.95 Table 6 (Concluded 1994 Coordinates 1996 Coordinates Target g Easting m(ft 1141264.00 | 1583641.16 2.307 (7.57) M31 1583841.04 | 8.022 (26.32) 32 1583797.22 | 7.199 (23.62) | 114110153 | 1583718.86 | 2640 (8.66) 1583915.30 | 7.714 (25.31) 1583751.03 | 2.908 (9.54) NR 37 1141735.31 | 1583674.44 3.642 (11.95) 1142043.96 | 1583463.74 4.167 (13.67) 3.755 (12.32) 1142293.55 jus | desea | resoerr2s | a7escrese) | 129 | rraaseooe | rssser7e0 | 00 (266) _| ne: jwnaoe | rr4zssase | tsesszess | aistitsse) | pace | rr4essao7 | rsesszeto | 4111 cae) _| a a ee Cr ec a es eee es es ee ee Ce eer es a ee es ee eee Elevation m(ft Monument/ Target = ) 3 ‘ e 1141264.04 | 1583641.16 2.334 (7.66) 1.04 | 8.059 (26.44) 1141136.13 | 1 Ed 797.23 | 7.199 (23.62) 1141101.44 | 1583718.77 2.670 (8.76) 1141063.64 | 1583915.28 7.772 (25.50) 1141011.01 | 1583751.03 2.908 (9.54) 137R 8 t “f ait hi Pees a Loa nes o x ‘ “a wea F , i a ds BR ih Ae y nn hen Ss ee a 2 e Pat : 3 r y yh i te » ‘ bf \ , ro \ hth ‘ “ ‘ é oe f t ca eae i} 7 4 é * ; ; vs yon : ake tacts Mog i , ¢ 1% i“ . = i WES x ae ; af 1 i sneer I ald t - , } nn) oo ee we AN NI wis aie ; oe ‘ie ai a 1 ta the Bek r ely J y ? f - Pe ee enna vec ind Appendix A Breakwater Topography, 1996 This appendix presents contour maps of the St. Paul Harbor breakwater exten- sion as a result of the photogrammetric analysis conducted in May 1996. Topog- raphy was developed using the digital terrain model (DTM) as stated in the main text of this report. The breakwater topography is shown on a 0.3-m (1.0-ft) contour interval. Elevations shown are in feet referred to mean lower low water (mllw) datum. Station numbering on the contour maps is a southerly to northerly direction. The scale of the maps is 2.54 cm = 6.1 m (1 in. = 20 ft). Appendix A Breakwater Topography, 1996 Al 3giS YOSYVH y8tZ+p8+9 els ‘9661 AeW ‘Veyemyeo1g UleEW JOqUeH [Neg ‘1S jo AydesHodo, *;y eunbi4 3ais vas Appendix A Breakwater Topography, 1996 ‘'3GIS YHOSUVH p8+6+78+8 BIS ‘9661 Aew ‘seyemyeasg UeEW JOQIeH [Neg 4S jo AydesBodo! ‘ey einbi4 5) ‘3201S Vas Appendix A Breakwater Topography, 1996 A4 . Topography of St. Paul Harbor main bre 3giS YOSUVH P8tZl-pEttl BIS ‘9661 AeW ‘Veyemyeasg ULeEW JOqUeH jNeg 1S jo AydesHodo| ‘oy aunbi4 adis vas NS Co) be 3 5 uy Q 7} ioe Oo a a s oe os : — ae D ra bt pessnes SEA SIDE Appendix C Breakwater Cross Sections, 1994 and 1996 Lh UROUEOU NOON oobaol houbouboon sauaa sh wevyrryveer ateeesnte ris atreraspcenter Figure C6. Cross sections of St. Paul Harbor main breakwater, stas 14+00 and 15+00 QO N JgIS YORYVH OO+Z| Pue OOTOL Se}s “eyemyeosg UTeEW JOQIEH [Neg }S JO SUOIDBS SSOID “ZO aunbi4 gals vas Appendix C Breakwater Cross Sections, 1994 and 1996 C8 HARBOR SIDE SEA SIDE Appendix C Breakwater Cross Sections, 1994 and 1996 ; | | | Figure C8. Cross sections of St. Paul Harbor main breakwater, sta 18+00 ?) o y ae ay ie TE Feveentiony. raion Destroy this report when no longer needed. Do not return it to the originator. 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