329 Race Street Philadelphia, PA TEL FAX bcausa.com

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1 329 Race Street Philadelphia, PA TEL FAX bcausa.com MEMO To: Cindy Petkac, Union Station Redevelopment Corporation (USRC) From: Lauren Drapala, Building Conservation Associates, Inc. (BCA) Dorothy Krotzer, Building Conservation Associates, Inc. (BCA) Date: July 16, 2014 Project: Union Station, Rostral Columns Conditions Assessment and Treatment Recommendations At the request of Cindy Petkac, Building Conservation Associates, Inc. (BCA) has prepared a memo on the present condition of the rostral columns at the east and west entrances of the south elevation of Union Station in Washington, D.C. The conditions assessment was performed as part of the Historic Preservation Master Plan that BCA is currently preparing for Union Station. The portion of the assessment related to the rostral columns has been extracted from this larger effort and presented in this memo so that USRC may provide information on the condition of the columns as part of a grant application to District Department of Transportation (DDOT). Lauren Drapala and Julianne Chianese-Wiesner of BCA performed a site visit on July 10, 2014 to inspect the granite bases, balustrade, cast iron columns, light fixtures and decorative sculptural elements that comprise the four rostral column installations. This assessment was documented primarily through on-site photography. This memo will summarize the conditions observed and provide general, prioritized recommendations for treatment. It should be noted that, in several instances, additional investigation, testing and review by other consultants (such as a structural engineer) will be required in order to more fully develop the scope of work for repair. Both the east and west entrances on the south elevation of Union Station contain a set of symmetrical column installations. For the purpose of discussion throughout this memo, the installations have been identified with alphanumerical references. (Figure 1) There is a primary walkway that corresponds to the arched opening of the station entrance, which is flanked on either side by large cast-iron composite order rostral columns, crowned with decoratively gilded eagles propped atop spherical bases. There are circular lighting fixtures on both sides of the column at the lower third of the shaft. The column sits on a granite base, approximately 66 tall by 60 wide, which is connected to a granite balustrade, approximately 122 long, which terminates at a smaller base for a light pole. The smaller base stands at the same height as the balustrade, approximately 40 tall, and supports a cast-iron light pole with a glass spherical lighting fixture atop. The west entrance is flanked by column installation 9A (Figure 2) at the west and 9B (Figure 3) at the east, while the east entrance is flanked by column installation 10A (Figure 4) at the west and 10B (Figure 5) at the east. Each element of the column installation will be discussed, followed by a discussion of conditions that are specific to individual elements, if noted. This survey only considered material condition issues related to the rostral column installations. The electrical systems for the related lighting components were not evaluated as part of this survey.

2 Overall Condition Granite Base and Balustrade The granite bases and balustrades of both column installations have a high degree of integrity. However, there are areas of deterioration and conditions requiring repair, some of which can be considered significant. In general, the west column installation (9A and 9B) exhibits worse conditions than the east column installation (10A and 10B), with several through-masonry cracks that will require partial disassembly in order to repair. Some cracking is significant and will require review by a structural engineer to evaluate the cause of the cracking. In both column installations, there are many open joints, which have allowed water to enter the structure resulting in displacement over time (from either freeze-thaw phenomenon or corroding internal anchors). (Figure 9) There is evidence of multiple repointing campaigns through each of the stone installations. There is disaggregation of the upper molding of the large granite base, which appears particularly pronounced on the west entrance. (Figure 6) The bases also have multiple anchors that have been installed in the granite faces, presumably used to secure previous signage, many of which are corroding. (Figure 7) Atmospheric soiling is extensive throughout each of the bases, with heavier surface accumulation at the east entrance (10A and 10B). Iron staining occurs most prominently along the top rails of the balustrade and the caps of the bases. (Figure 8) 9A- West Column, West Entrance - On the middle pier, there are significant cracks that extend through the north and south faces, causing a corner of the pier to separate. (Figure 10) - There are traces of graffiti on the east face that have not been fully removed. (Figure 11) - Slight variation in the appearance of the balusters indicate that some balusters may have been replaced over time. (Figure 12) - A unique metal bracket is still embedded on the west end of the base, just under the cast iron light pole. (Figure 13) 9B- East Column, West Entrance - There are large vertical cracks through the center of each face of the large granite base on which the rostral column sits. Many of these cracks have been previously repaired with patching material, but they have re-opened over time. In addition, there is evidence of leaching lime and/or salts coming from these cracks, suggesting active water infiltration. This condition should be investigated to determine the cause of the cracking. It should also be evaluated by a structural engineer to make sure that the base can adequately support the weight of the column. (Figure 14) - Diagonal cracking is visible at the upper corner of the middle pier of the balustrade, similar to that identified on the middle pier of 9A. This through-unit crack is causing a large spall at the corner of the pier. The source of the crack, which may be related to internal iron anchors that are corroding in the presence of water, should be investigated. (Figure 16)

3 - There is isolated cracking in portions of the top molding of the balustrade. (Figure 15) - Corroded abandoned anchors are present on the south face of the middle pier of the balustrade. (Figure 16) - Sugaring is also visible on approximately 3-4 balusters on the north face of the balustrade. (Figure 17) - There is also an isolated loss at the southeast corner of the smaller light pole granite base. (Figure 18) 10A- West Column, East Entrance - There are appreciably more abandoned anchors in the surface of the large granite base. Many of these anchors are corroded and resulting in staining on the face of the granite. (Figure 19) - Traces of black and white coatings, most likely paint, are present along the western side of the balustrade railing. (Figure 20) - There are isolated areas of loss at the southeast corner of the large granite base (Figure 21). - The balusters are consistent in appearance and texture, with pronounced iron staining throughout. - One baluster has been patched on its north face. (Figure 22) In comparison to the installations at the west entrance, the central pier does not illustrate the same diagonal cracking. 10B- East Column, East Entrance - The large granite base under the rostral column is cracked on the north and south faces along the upper profiled molding. The cause of the cracking was not identified during this preliminary survey but may be related to the way in which the rostral column is anchored and the possible corrosion of the anchor. (Figure 25). - There is isolated loss of granite from balusters (Figure 23) and the base of the cast iron light post (Figure 24). - The balustrade appears to have moved over time, likely due to pervasive open joints that have allowed water to enter the assembly (causing any internal anchors or possibly causing internal pressure from free-thaw phenomenon). (Figure 24) Cast Iron Columns and Light Posts - The cast iron substrate is in good condition on all columns, although there are many small areas of surface corrosion where the paint is flaking and peeling. (Figure 26) - Corrosion is most prevalent at points of junction, at metal-to-metal connections as well as metal-to-stone connections. (Figure 27) These areas have a propensity to collect water. - The light posts, and to a lesser extent the rostral columns, contain many metal brackets previously used to hold signage. These brackets have been sensitively installed and have been fastened to the poles through tension rings around the perimeter of the columns. Many of them are corroding and resulting in further staining of the decorative cast iron and granite bases. (Figure 28)

4 - The access panels for the light pole base are often not secured in place and have become places where trash is placed. (Figure 29) Light Fixtures - Three opaque white spheres are installed in each column installation, with the two smaller globes on either side of the rostral column (Figure 30) and one larger globe on the top of the light post (Figure 31). - These glass spheres are further enhanced with metal straps that follow the vertical and horizontal curvature of the globe. These elements are intact in each of the installations and appear to be well preserved although generally soiled, based on observations from the ground. Decorative Eagle Sculptures - Each rostral column serves as a pedestal for a sculpture of an eagle with wide wingspread perched atop a sphere. These cast metal elements have been finished with gold (either gilding or paint, or a combination of both), with one exposed horizontal cast iron band around the globe. The eagles appear to be in sound condition, although the finishes are fairly deteriorated, resulting in flaking and inconsistent finish across the sculpture surface. (Figures 32-33)

5 Recommendations for Treatment The following prioritized recommendations for both rostral column installations are based on the conditions observed during the visual inspection performed by BCA. In many instances, additional investigation, testing and review by other consultants (such as a structural engineer) will be required in order to more fully develop the scope of work for repair. Granite Base and Balustrade The causes of the cracks in the granite piers and bases of column installation 9A and 9B should be investigated. It is possible that the cause of related to either corroding internal anchors or freeze-thaw phenomenon associated with water entering the assembly through the numerous open joints in the stonework. For the column base in particular, a structural engineer should be consulted to evaluate the cause of the cracks present on every face of the base and determine whether there is any concern about the base being able to adequately support the weight of the cast iron column. Once the cause of the cracking in the granite bases and piers is diagnosed and addressed, the cracks should be repaired. In order to repair the cracked piers, partial disassembly of the balustrade will be required. The top rails above the cracked piers will need to be removed in order to access the piers. The piers will then need to be removed or repaired in situ by installation of a dutchman piece at the corner (in the location of the cracking). Re-assembly of any removed pieces should include re-setting using stainless steel pins set in epoxy or lead. Smaller cracks in the stone that are more superficial in nature can be repaired through injection with a cementitious grout or a patching mortar. Any losses in stone should be compensated, either with a cementitious patching material or a stone dutchman repair. Because multiple pointing mortar campaigns are present on the structure, a mortar analysis should be completed to determine an appropriate restoration mortar. Once an appropriate re-pointing mortar has been identified, both column installations should be completely re-pointed. The granite should be cleaned in an effort to remove surface soiling, ferrous staining on the upper stone courses and traces of graffiti. Tests should be performed to determine the best means of cleaning the stone. Abandoned anchors that are corroding should be removed from the stone and these openings should be patched with a composite patching mortar that matches the appearance of the surrounding stone. Cast Iron Columns and Light Posts The original finish scheme of the cast iron columns and light posts should be documented through paint analysis so that it can be replicated as part of the restoration work. The existing finishes should also be tested for the presence of lead paint. The surface of each cast-iron element should be thoroughly scraped and/or abraded to remove any loose or unstable paint on the surface. Similarly, areas of corrosion should be thoroughly prepared to expose sound, stable metal substrate.

6 Any gaps or openings in the cast-iron should be sealed with a sealant intended for use with metal. Joints between metal and stone should also be sealed with an appropriate metal-to-stone sealant to prevent water entry. Cracks or small losses in the metal should be filled with a metal-filled epoxy that has the ability to be shaped or tooled. Access panels should be secured in place with appropriate, locking hardware. Light Fixtures The glass spheres should be removed during the preparation and re-painting of the castiron surfaces of the columns. During this time, they should be thoroughly cleaned on the interior and exterior. Once re-finishing of the columns has been completed, the lighting fixtures should be re-installed, with any necessary electrical infrastructure improvements needed to make the lighting system operable. Decorative Eagle Sculptures The eagle sculptures appear to have multiple finish campaigns. A thorough finishes analysis should be completed to determine the original finish scheme so that it can be replicated as part of the restoration.

7 Figure 1. Site plan of Columbus Plaza, identifying unique components, unscaled. The rostral columns are noted, the west entrance at the upper left corner (elements 9A and 9B) and the east entrance at the upper right corner of the image (elements 10A and 10B). Figure 2. The south face of element 9A, at the west entrance on the south elevation of Union Station, 2014.

8 Figure 3. The south face of element 9B, at the west entrance on the south elevation of Union Station, Figure 4. The south face of element 10A, at the east entrance on the south elevation of Union Station, 2014.

9 Figure 5. The south face of element 10A, at the east entrance on the south elevation of Union Station, Figure 6. Disaggregation of the profiled granite molding on the rostral column base.

10 Figure 7. Multiple anchors have been installed in the granite base. These elements are corroding, resulting in staining of the granite. Figure 8. Extensive soiling is present throughout the granite portions of the installation. There is predominant staining on the top moldings of the bases and balustrades from corrosive ferrous elements, including the columns themselves.

11 ( Figure 9. Open and cracked mortar joints are pervasive throughout the stone bases. The open joints allow water into the junctures between stone elements. Figure 10. Cracking through the middle pier of the balustrade on element 9A. This image shows the north face of the pier, but this condition also extends into the south face.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

12 ( Figure 11. Traces of graffiti, or possibly adhesive from prior signage, remain on the east face of the large granite base on element 9A. Corroding abandoned metal anchors are also visible on the surface of the stone. Figure 12. Variations in the appearance of elements on the balustrade on element 9A indicate that some elements may have been replaced. The arrows highlight two elements that appear different from each other.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

13 ( Figure 13. Metal bracket on the west face of element 9A. Figure 14. Vertical cracking and leaching of lime and/or salts is visible on every face of the large granite base of element 9B. This image shows the south face, which has been previously patched, but is currently cracked.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

14 ( Figure 15. Isolated cracking in the upper profiled molding of the large granite base, at the southeast corner of element 9B. Figure 16. Cracking through the middle pier of the balustrade on element 9B. This image shows the south face of the pier, but this condition also extends into the north face.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

15 ( Figure 17. Disaggregation of the baluster bases on the north face of element 9B. Figure 18. Loss of granite at the southeast corner of the smaller light post base of element 9B. The damage is most likely the result of impact.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

16 ( Figure 19. Abandoned ferrous anchors in the east face of the granite base of element 10A. Figure 20. Black coating (most likely paint) on the western portion of the top railing of element 10A.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

17 ( Figure 21. Loss of profiled granite base molding at the southeast corner of the large granite base of element 10A. Figure 22. Iron staining of balustrade from ferrous corrosion in element 10A.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

18 ( Figure 23. Loss of granite at the top of a baluster in element 10B. Figure 24. Loss of granite at the northwest corner of the smaller light post base in element 10B, indicated by red arrow. Visible open joints in this area also indicate slight movement of the balustrade railing from the light post base (blue arrow).!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

19 ( Figure 25. Vertical crack running through the center of the top granite piece on the smaller light post base in element 10B. The crack is both visible on the north face (shown above) and south face. Figure 26. Small areas of surface corrosion are visible in areas of flaking and peeling paint throughout the columns.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

20 ( Figure 27. Detail of corroded cast iron base of a light post at the junction between the metal and stone. This area is particularly prone to water infiltration and pooling and should be sealed. Figure 28. Metal brackets are used to hold signage on the light posts, and to a lesser extent, the rostral columns. The light post on element 10A (shown) is the only feature surveyed with a sign attached.!"#$%#&'()*&+,-./0#*&(/++*)#/0,+(#&)(

21 Figure 29. Unsecured access panel at the base of the light post. Figure 30. Detail of the two smaller lighting fixtures on the east and west sides of the rostral columns.

22 Figure 31. Detail of the larger spherical light fixture on the top of the light pole columns. Figure 32. Decorative eagle atop the rostral column of element 10B. The design complements the sculpted eagles on the south elevation of Union Station.

23 Figure 33. Detail of the decorative eagle atop the rostral column of element 10A. Note the inconsistent finish across the sculpture, and presence of bird activity that is likely contributing to the deterioration of the finish.