7_ATT_6_PHYSICAL_DATA.pdf

Vanderbilt Mansion National Historic Site

Examination of Mortar Samples Report Addendum

Introduction At the request of Katherine Onufer of John G. Waite Associates, Architects (JGWA), we examined an additional mortar sample from Vanderbilt Mansion National Historic Site in Hyde Park, New York. This sample was removed from a brick pier of the north portico in December 2013 and identified as “M8 Mortar from piers below north portico.” The sample location was noted on the attached Mortar Samples Key Plan provided by JGWA.

Because the M8 sample was very small, the goal of our examination was to visually compare it to the Vanderbilt Mansion mortar samples that we examined during December 2013. This report is an addendum to our January 2014 report.

Methodology The sample was first examined using a variable magnification (10 - 63x) Nikon SMZ 800 Stereomicroscope, equipped with fiber optic illumination and a Nikon NIS-Elements imaging system. The binder color of the sample was matched to a color chip of the Munsell Color System.

A portion of the M8 sample was pulverized using a ceramic mortar and pestle, and then weighed using an Ohaus electronic balance. Dilute hydrochloric acid was slowly added to the pulverized sample to digest the acid soluble component. Following acid digestion, sand was separated from the fines using a filtration process. The sand component was collected and oven dried at 100 degrees Fahrenheit. Photomicrographs of the mortar sample and its sand component follow the Results section of this report.

Results

Description

The M8 mortar sample is comprised of many small, thin pieces, with the largest measuring approximately ½” x ¼.” The sample envelope also contains occasional small reddish-colored bits that appear to be from the brick substrate. Although the mortar binder appears to be whitish in color, most of the samples are discolored on one or both sides. Some of the pieces appear to have a gray coating that matches Munsell 10YR 6/1.

Binder color: pale beige, Munsell 10YR 9/1

Sand Grain size: uniformly small Grain shape: sub-angular and rounded

Colors: predominately clear, colorless and white with occasional light brown and black grains. The reddish-colored particles appear are likely from the brick substrate.

Comments Comparing the M8 mortar sample with the previously examined Vanderbilt Mansion samples was difficult. The M8 sample was comprised of very small pieces and many were covered with a gray coating. However, the M8 binder was similar in color to that of most of the other mortar samples. In addition, the M8 sand component had similar colors and grain sizes and shapes. It was not possible to determine whether the M8 mortar dates from the original construction of Vanderbilt Mansion or whether it is a repointing mortar. Further examination of the mortar sample by a cement petrographer could confirm the composition of the M8 binder and provide additional information about the sand components.

Submitted by Frances Gale March 6, 2014

Photomicrographs

M8 mortar showing white binder and area with gray discoloration, 20x

M8 mortar showing gray-colored coating, 10x

M8 sand, 10x

M8 sand, 20x

Note: The reddish-colored particles in the sand component are likely from the brick substrate.

FRANCES GALE

ARCHITECTURAL CONSERVATOR

4213 SHOALWOOD AVENUE

AUSTIN, TX 78756

VANDERBILT MANSION

EXTERIOR CLEANING TESTS

INTRODUCTION

At the request of John G. Waite Associates, Architects, Frances Gale returned to Vanderbilt Mansion National Historic Site in Hyde Park, New York, on November 7-8, 2013. This site visit provided an opportunity to evaluate the appearance of exterior limestone where cleaning tests were carried out in December 2010 and April 2011. During our November 2013 site visit, we also conducted cleaning tests on limestone pavers and lower walls of the west portico. Matthew Scheidt and Katherine Onufer of John G. Waite Associates Architects were present on both days and Artur Matia of Matia Historic Restoration and Design assisted with the cleaning tests on November 8th. The weather was mostly sunny on November 8th with temperatures in the 40s.

The report below includes an evaluation of resoiling that has occurred on limestone that was cleaned during previous site visits and a summary of the cleaning tests that were carried out in November 2013 site visit. Updated recommendations are provided for cleaning exterior limestone of Vanderbilt Mansion.

EVALUATION OF PREVIOUS CLEANING TESTS

Test areas #1-4 are located on the west elevation of Vanderbilt Mansion. Limestone of test area #1 was evaluated from the ground level. Test areas #2, #3 and #4 were evaluated from the ground level with binoculars and from an aerial lift. Photographs (Figs. 1-10) compare the cleaned appearance of limestone in the 2010 and 2011 test panels with its November 2013 appearance.

Test area #1 Location: Vertical wall below 1st story at the stairway at the north end Conditions: Severe biological growth Products/ Techniques: December 2010 Hot water pressure washing; D/2 Biological Solution April 2011

D/2 Biological Solution; hot water pressure washing followed by D/2 Biological Solution

Evaluation: There was slight resoiling present in each of the limestone panels of Test area #1.

Those cleaned with D/2 Biological Solution showed the least amount of resoiling.

Photographs: Figs. 1-2

Test area #2 Location: 1st story window hood Conditions: Biological growth and atmospheric soiling with slight weathering crust Products/ Techniques: December 2010 Hot water pressure washing Evaluation: Limestone of Test area #2 that was cleaned with hot water pressure washing showed a moderate amount of resoiling.

Photographs: Figs. 3-4

Test area #3 Location: Capstone above entablature Conditions: Moderate atmospheric soiling and biological growth Products/ Techniques: December 2010 MasonRe B All Purpose Cleaner 2010 All Surface Cleaning April 2011 942 Limestone & Masonry Cleaner Evaluation: In Test area #3, limestone that was cleaned with 2010 All Surface Cleaner and

942 showed minimal resoiling; limestone cleaned with MasonRe B All Purpose Cleaner showed moderate resoiling.

Photographs: Fig. 5-8

Test area #4 Location: Cornice Conditions: Biological growth in exposed areas above the modillions with severe atmospheric soiling and blackened weathering crust in protected areas Products/ Techniques: April 2011

Intermittent misting followed by hot water pressure washing Intermittent misting followed by scrubbing and hot water pressure washing; hot water pressure washing; 942 Limestone & Masonry Cleaner (modillion only); hot water pressure washing followed by 2010 All Surface Cleaner; hot water pressure washing following by D/2 Biological Solution

Evaluation: Limestone cleaned with hot water pressure washing followed by 2010 and with hot water pressure washing following by D/2 showed minimal resoiling. With all other cleaning products and techniques, there was moderate resoiling.

Photographs: Figs. 9-10

ADDITIONAL CLEANING TESTS

Additional cleaning tests were conducted during our November site visit on horizontal pavers and lower walls of the west elevation Portico. Test areas were approximately 6” x 8” in size. Cleaning products included 2010 All Surface Cleaner, a mildly alkaline detergent cleaner, and EnviroKlean ReVive, a cleaning product for removing biological growth. ReVive contains a quaternary ammonium compound and its composition is very similar to D/2 Biological Solution, the cleaning product used in previous on-site tests.

In addition to the chemical cleaning products, hot water pressure washing was also evaluated.

Water was heated to 180o Fahrenheit, and water pressure was approximately 1000 psi. A 45-degree fan tip was used, maintaining a distance of 8-10 inches from the limestone surface. At the end of dwell periods, hot water pressure washing also was used for rinsing the test areas cleaned with 2010 and ReVive. Test areas were evaluated following drying.

The tables below provide information about the products and procedures used in both test areas.

Photographs (Figs. 11-21) show the before and after appearance of limestone of the test areas.

Product data sheets and Material Data Sheets for cleaning products are attached.

Test Area #5: Biological growth and general soiling Location: West elevation portico, horizontal pavers

Product Preparation Application Results, % effective

Photographs

Concentrate

Brush applied to prewet surface. Reapplied with scrubbing during a 5 minute dwell period.

90%

Figs. 11-12

Revive surface. Reapplied with

Figs. 11 and 13

Hot water pressure washing

180o F. at ~1000 psi

Figs. 14-15

Test Area #6: Biological growth and general soiling Location: West elevation portico, lower wall on north side

Product Preparation Application Results, % effective

Photographs surface. Reapplied with

85%

Figs.16 and 18

Revive concentrate surface. Reapplied with

Figs. 16-18 pressure washing

Figs. 17-18 pressure washing followed by ReVive surface. Reapplied with

Fig. 19-20

Following our evaluation, hot water pressure washing was used to even out the appearance of limestone of the lower portico wall of test area #6 (Fig. 21).

COMMENTS

In Test areas #5 and #6, all of the products and techniques were effective in removing biological growth and atmospheric soiling from the limestone pavers and lower wall of the portico. With the latter, cleaning results were slightly better when hot water pressure washing preceded cleaning with ReVive.

RECOMMENDATIONS:

Our November 2013 site visit to Vanderbilt Mansion National Historic Site provided an opportunity to evaluate resoiling of the cleaning tests conducted on exterior limestone in December 2010 and April 2011. Based on the appearance of limestone in Test areas #1-4, it appears that resoiling was minimized in areas where a biocidal product (D/2 Biological Solution) was used.

Based on our evaluation of previously cleaned test areas, and the results of on-site testing conducted in November, our recommendations for cleaning exterior limestone are as follows:

General soiling and biological growth Water washing applied at approximately 1000 psi with a 45-degree fan tip, maintaining a distance of 8-10 inches from the limestone surface. Hot water (approximately 180 degrees F.) may improve effectiveness. To minimize resoiling, we recommend cleaning with D/2 Biological Solution or EnviroKlean ReVive. Per the manufacturer’s instructions, D/2 Biological Solution should be applied in concentrate. With EnviroKlean ReVive, the cleaner should be applied in concentrate for heavy biological staining and diluted 1 part cleaner to 5 parts water for moderate biological staining, and diluted 1 part cleaner to 10 parts water for light biological staining.

Gray soiling (such as that present on the capstone) 942 Limestone & Masonry Cleaner applied in concentrate

Weathering crust formation Intermittent misting using 15 and 25-degree tip spray brass nozzles spaced 6 inches apart and connected to flexible adapters. The nozzles should be approximately 10-12 inches from the limestone surface, providing misting at a 120-degree angle. Misting cycles of 10 minutes on and 50 minutes off during an 18-hour period were effective in the tests that we conducted. Because exterior limestone conditions are variable, the technique may require slight adjustments when cleaning is carried out. Hand scrubbing with a soft brush and water washing should be used to remove the soiling that was loosened during intermittent misting. To minimize resoiling, we recommend cleaning with D/2 Biological Solution or EnviroKlean ReVive following intermittent misting. D/2 Biological Solution should be applied in concentrate and EnviroKlean ReVive should be diluted 1 part concentrate to 5 parts water.

Frances Gale January 7, 2014

PHOTOGRAPHS

Fig. 1, Test area #1, showing (left to right) hot water pressure washing, D/2 (December 2010) and D/2, hot water pressure washing followed by D/2 (April 2011)

Fig. 2, Test area #1, showing resoiling of limestone (November 2013)

Fig. 3, Test area #2, hot water pressure washing test results (December 2010)

Fig. 4, Test area #2, showing resoiling (November 2013)

Fig. 5, Test area #3, 942 test results (April 2011)

Fig. 6, Test area #3, MasonRe B test results (December 2010)

Fig. 7, Test area #3, 2010 test results (December 2010)

Fig. 8, Test area #3, showing (left to right) resoiling of limestone cleaned with 942, MasonRe B, 2010 (November 2013)

Fig. 9, Test area #4, test results for (left to right) Intermittent misting followed by hot water pressure washing Intermittent misting followed by scrubbing and hot water pressure washing Hot water pressure washing 942 (modillion only) Hot water pressure washing followed by 2010 Hot water pressure washing following by D/2 (April 2011)

Fig. 10, Test area #4, showing resoiling (November 2013)

Fig. 11, Test area #5 before cleaning with 2010 and Revive (November 2013)

Fig. 12, Test area #5, after cleaning with 2010 (November 2013)

Fig. 13, Test area #5 after cleaning with ReVive (November 2013)

Fig. 14, Test area #5 before cleaning with hot water pressure washing (November 2013)

Fig. 15, Test area #5 after cleaning with hot water pressure washing (November 2013)

Fig. 16, Test area #6 before cleaning with 2010 and ReVive (November 2013)

Fig. 17, Test area #6 after cleaning with ReVive, left, and before cleaning with hot water pressure washing, right (November 2013)

Fig. 18, Test area #6 after cleaning with 2010, ReVive and hot water pressure washing (November 2013)

Fig. 19, Test area #6 before cleaning with hot water pressure washing followed by ReVive (November 2013)

Fig. 20, Test area #6 after cleaning with hot water pressure washing followed by ReVive (November 2013)

Fig. 21, Test area #6 after final hot water pressure washing (November 2013)

WESTERN ANALYTICAL LABORATORY, Inc.

TEST REPORT

REPORT NO: 92701

DATE RECEIVED: January 8, 2014

DATE REQUIRED: January 9, 2014

CLIENT: Dave Hayes – National Park Service 4097 Albany Post Road Hyde Park, NY 12538

REFERENCE: 81 Vanderbilt Park Road Hyde Park, NY

SUBJECT: Polarized Light Microscopy Analysis for Asbestos; 1 sample

METHODOLOGY: "Method for the Determination of Asbestos in Bulk Building Materials"

(EPA 600/R-93/116)*

ACCREDITED: National Institute of Standards and Technology (NVLAP) # 200037

SAMPLE ID

NUMBER

SAMPLE LOCATION

AND DESCRIPTION

VISUAL

DESCRIPTION

ASBESTIFORM

MINERALS

OTHER FIBROUS

MATERIALS

NON-FIBROUS

MATERIALS

Basement Window

Window glazing

Beige-gray granular

Non-friable

None Detected None Detected Granular Minerals t: Trace >1% = greater than 1% <1 = less than 1%

This report only applies to the sample(s) tested. Supporting laboratory documentation is available upon request. This report must not be reproduced except in full, unless approved by Western Analytical. The client is solely responsible for the use and interpretation of test results and reports requested from Western Analytical. This report must not be used by the client to claim product endorsement by NVLAP or any other agency of the U.S. Government.

12734 Branford St. #19, Arleta, CA 91331 • (818) 899-0949 phone • (818) 899-0399 fax

PETROGRAPHIC AND X-RAY DIFFRACTION ANALYSES OF:

Vanderbilt MansionNHS Hyde Park, NY

Portico Floor Stone Tile sample

One 85 x 48 x 11 mm chip of beige, massive, fine-grained dolostone with minor detrital quartz and a trace of iron oxides (probably pyrite, originally). The weathered surface is heavily coated with algae/lichens.

Xray diffraction analysis (Fig. 1) of the material near the weathered surface indicates the stone is dominantly dolomite (CaMg(CO3)2) with minor quartz (SiO2).

Fig. 1. Powder X ray diffractogram of dolostone sample. The material analyzed was taken from the weathered surface to a few millimeters below the weathered surface. Cu Ka radiation, 30kV, 15mA.

Petrographic examination of the sample shows the main part of the stone to contain fine-grained dolomite (Fig. 2). The dolomite grains deeper in the unaltered portion of the sample (Fig. 2a) are tightly packed, some as anhedral to subhedral grains, others showing euhedral rhombohedral crystal forms. The dolomite grains near the surface (Fig. 2b) tend to be anhedral, smaller, and loosely packed, probably due to dissolution by the algae/lichens. Hyphae/rootlets (Fig. 3) penetrate the stone to a depth of about 1mm by selectively corroding the dolomite grains, loosening them from one another. The deterioration of the stone by the the hyphae corresponds to the depth of the surficial flaking. Alizarin Red S staining indicates that calcite is present primarily in the altered surficial layers; perhaps the lichens selectively remove magnesium from the dolomite. Small (<5µm) grains of iron oxides are scattered throughout the stone. No pyrite was observed, and mercuric nitrate staining did not detect the presence of any gypsum. The iron oxides might have originally been pyrite grains that were oxidized during dolomitization of the original limestone.

Fig. 2, SEM images. a) Fresh dolostone. b) Deteriorated dolostone on a flaking surface. Both images are at the same scale, showing the smaller grain size due to corrosion of the dolomite grains.

Back-scattered electron image, 20kV.

Figure 3. Hyphae penetrating stone, and wrapping around dolomite grains. This material is immediately beneath the lichen thallus exposed on the weathered surface, on top of the material shown in Fig. 2b. SEM back-scattered electron image, 20kV.

The heavy lichen/algae coating on the exposed surface, coupled with the features described above, suggests that the deterioration of the dolostone is primarily due to attack by acids released by the hyphae. The presence of calcite primarily in the deteriorated flakes beneath the lichen suggests that the lichen preferential takes up Mg, leaving the Ca as calcite. The deterioration does not appear to be related to oxidation of pyrite in the original stone.

Major: Dolomite (CaMg(CO3)2) Minor: Quartz (SiO2) Trace: Calcite (CaCO3), iron oxides

Respectfully submitted by

James B. Murowchick, Ph.D.

Consulting Mineralogist Lenexa, KS 24 May 2014