SMMA Carving RFP.docx

Stone Mountain Carving Cleaning and Preservation RFP

STATE OF GEORGIA

REQUEST FOR PROPOSAL

ISSUED BY: STONE MOUNTAIN MEMORIAL ASSOCIATION

PROPOSAL RELEASE DATE: JULY 22, 2026

CLEANING AND PRESERVATION OF STONE MOUNTAIN MEMORIAL CARVING

Table of Contents

INTRODUCTION

PURPOSE OF REQUEST FOR PROPOSALS

The Stone Mountain Memorial Association ("SMMA" or the "Owner") is soliciting proposals from qualified firms to provide cleaning and preservation services for the Confederate Memorial Carving (the "Carving") on the north face of Stone Mountain. The Carving is a historic resource of significant importance, and all work must be performed with a high degree of care to ensure that the cleaning method does not damage, abrade, or otherwise degrade the Carving in any way.

BASIC GUIDELINES FOR THIS REQUEST FOR PROPOSAL

The Stone Mountain Memorial Association has determined that the use of competitive sealed proposals will be most practical and advantageous to the State in completing the acquisition of the services described herein.

All submitted proposals shall be evaluated in accordance with the evaluation criteria set forth in this Request for Proposals. After the opening of the sealed proposals, discussions may be conducted by the Stone Mountain Memorial Association with responsible Contractors who may be selected for award, for the purpose of clarification to assure full understanding of, and responsiveness to, the solicitation requirements. Contractors shall be accorded fair and equal treatment with respect to any opportunity for discussion and revision of proposals; and such revisions may be permitted after submissions and prior to award for the purpose of obtaining best and final offers.

In conducting such discussions, there shall be no disclosure of any information derived from proposals submitted by competing Contractors. All such discussions shall be jointly conducted by the Issuing Officers named below:

2027 Old Hugh Howell Rd Stone Mountain, GA 30083 2027 Old Hugh Howell Rd Stone Mountain, GA 30083

An award may be made to the Contractor whose proposal is determined in writing to be the most advantageous for the Stone Mountain Memorial Association, considering all the evaluation factors set forth in this RFP. The Stone Mountain Memorial Association reserves the right to reject all proposals submitted in response to this request and to not proceed with an award from this solicitation.

RFP SCHEDULE

SCHEDULING SITE VISIT

Each respondent will be given the opportunity to evaluate the Carving in person. Site visits must be scheduled at least 48 hours in advance. Scheduling requests must be made via email to procurement@stonemountainpark.org.

RESTRICTIONS ON COMMUNICATION

From the issue date of this RFP until a successful Contractor is selected and the selection is announced, Contractors are not allowed to communicate for any reason with any SMMA board member or any staff member or other personnel associated with the State of Georgia, including the SMMA and the current park operator, except through the Issuing Officers named herein, their appointed representatives, or as provided by existing work agreement(s). For violation of this provision, the Stone Mountain Memorial Association shall reserve the right to reject the proposal of the offending Contractor. All substantive questions concerning this RFP must be submitted in writing to the Issuing Officers. No questions other than written will be accepted. No response other than written will be binding upon the Stone Mountain Memorial Association.

DEFINITION OF TERMS

· Contractor: Respondent to this Request for Proposal

· Owner: Stone Mountain Memorial Association

· RFP: Request for Proposal

· SMMA: Stone Mountain Memorial Association

BACKGROUND

CARVING DESCRIPTION

The Carving is cut directly into the native granite of the mountain’s north face and depicts three figures on horseback. It measures approximately 190 feet wide by 90 feet high, is recessed as much as 42 feet into the rock and sits roughly 400 feet above the surrounding ground. Carving commenced in 1923 and was completed in 1972. The Stone Mountain Memorial Association was established, and the memorial provided for, under O.C.G.A. § 12-3-190 et seq.

CURRENT CONDITION OF CARVING

The Carving is currently structurally sound, with no significant new structural concerns identified. Primary issues are aesthetic and biological, as detailed in Exhibit A.

Cleaning test sites established in 2017 are now in significant decline. Of the approaches tested, high-pressure hot-water steam combined with chemical treatment demonstrated the best long-term retention of results, particularly in areas subject to direct water flow (Exhibit C). Current conditions, photographs, and prior results are documented in the SMMA 2025 Annual Monitoring Report (Exhibit A). Comment by Nic Matthews: Do we have a report that we could exhibit documenting the different cleaning approaches? Comment by Doehrman, Amy: Working on getting this. The 2025 report shows those areas with foot notes, but I agree it would be helpful to have the full report.

SCOPE OF WORK

Pre-Construction Condition Assessment Prior to beginning any cleaning, preservation, or repair work, the Contractor shall conduct and submit to the Owner a comprehensive Pre-Construction Condition Assessment of the Carving. The assessment shall establish the baseline condition of the Carving and shall include, at a minimum:

· High-resolution color photographs of the entire Carving, surrounding tablet, and all significant features;

· Close-up photographs and documentation of all existing cracks, exfoliation, dutchmen, caulking, patches, previous repairs, and other areas of concern;

· Documentation of the extent and location of biological growth, including lichen, algae, moss, vegetation, staining, and accumulated surface deposits;

· Documentation of existing water runoff patterns, staining, and moisture-related conditions;

· Identification and mapping of any loose rock, debris, or vegetation requiring attention;

· A written condition assessment identifying any existing deterioration, defects, or maintenance concerns; and

· Documentation of any additional conditions identified during the pre-construction assessment, together with recommendations for corrective action.

The Pre-Construction Condition Assessment shall be submitted to and accepted by the Owner prior to commencement of any cleaning or preservation activities and shall serve as the baseline for evaluating the completed work.

TEST PANEL

Prior to beginning the full cleaning, the Contractor shall clean a discrete, inconspicuous test panel of approximately two feet by two feet for each representative surface and soiling type, using the proposed method(s) and product(s). Test panels shall be evaluated and approved in writing by the Owner before general cleaning proceeds. The approved test panel shall serve as the standard of quality for all subsequent work.

CLEANING AND BIOLOGICAL GROWTH REMOVAL

The Contractor shall perform comprehensive cleaning of the Carving and surrounding tablet using preservation methods appropriate for historic granite. The work shall include:

· Removal of lichen, algae, moss, vegetation, and other biological growth;

· Removal of environmental staining, discoloration, and accumulated surface deposits;

· Cleaning of carved surfaces without damaging or altering the historic granite or carved details; and

· Protection of adjacent granite surfaces during all cleaning operations.

PRESERVATION REPAIRS

The Contractor shall inspect and perform preservation repairs identified in the SMMA 2025 Annual Monitoring Report (Exhibit A) and the pre-construction condition assessment as necessary, to maintain the integrity of the Carving. The work shall include:

· Stabilization, maintenance, repair, or replacement of deteriorated caulking, Dutchmen, and localized preservation features; and Comment by Nic Matthews: Not sure I follow what this is or if its referring to the men in the carving? Comment by Doehrman, Amy: This was in the report, but In historic preservation and construction, a Dutchman (or Dutchmen) is a precisely fitted patch or inset of new material (like wood or stone) used to repair a small, damaged area. Comment by Nic Matthews: Marking as resolved. I need to get up to speed on my stone carving terminology

· Removal of loose rock and debris located above the Carving and below the fence line, where safely accessible and directed by the Owner.

FINAL CONDITION ASSESSMENT

Upon completion of the work, the Contractor shall submit a Final Condition Assessment Report documenting the completed project. The Contractor shall prepare a written and photographic condition report documenting the same features identified in the Pre-Cleaning Condition Report, including:

· A summary of all cleaning and preservation activities performed;

· Documentation of all repairs completed;

· Areas where satisfactory cleaning could not be achieved and the reasons;

· Any new conditions identified during the work; and

· Recommendations for future monitoring and maintenance.

PROJECT COST

Proposals should be structured to deliver the full scope of work inclusive of all labor, materials, equipment, access and rigging systems, supervision, environmental and safety compliance, and the documentation deliverables required under Section 4. The Owner reserves the right to negotiate scope, phasing, or unit pricing with the selected firm to align the final award with available funds.

EXPECTATIONS

GENERAL REQUIREMENTS

The Contractor shall provide all labor, materials, tools, equipment, staging, access systems, personal protective equipment, Safety Data Sheets, supervision, transportation, and operations required to complete the work described herein. The Contractor is responsible for full compliance with all applicable federal, state, and local laws, regulations, and codes.

All cleaning shall employ the gentlest means possible that will achieve an acceptable result. The Carving is a significant historic resource on exposed granite; protocols developed for masonry or softer stone are not applicable and shall not be used. Aggressive cleaning intended to make the Carving look new is neither expected nor permitted. Reasonable expectations include the retention of some weathering, patina, and biological staining consistent with the age of the resource and its exposed outdoor position.

PROTECTION OF THE MONUMENT, SITE, AND PUBLIC

The Contractor shall take all necessary precautions to protect the Carving, surrounding site, park visitors, and adjacent improvements throughout the duration of the project. At a minimum, the Contractor shall comply with the following requirements:

· Isolate and secure the work area with fencing and other appropriate measures for the duration of the work to prevent unauthorized access by the public.

· Adjacent plantings, turf, hardscape, plaques, and site furnishings shall be protected from overspray, runoff, and chemical exposure; planted areas exposed to cleaning solutions shall be rinsed with water.

· Runoff shall be managed and disposed of in compliance with all applicable environmental regulations; no cleaning solutions shall enter storm drains where prohibited.

· Comply with all OSHA requirements, provide appropriate personal protective equipment, and maintain Safety Data Sheets on site for all products used.

· Continuously monitor the condition of the Carving throughout all phases of the work. If any evidence of cracking, spalling, exfoliation, sugaring, loss of material, discoloration, or any other condition indicating potential damage is observed, the Contractor shall immediately suspend work in the affected area, notify the Owner, and take no further action until authorized by the Owner.

SITE ACCESS AND WORK AT HEIGHT

The Carving is on a near-vertical granite face several hundred feet above grade. The Contractor is responsible for furnishing and operating all access and fall-protection systems required to reach the work, which may include rope access / industrial climbing, suspended scaffolding, or other engineered systems. Personnel performing rope-access or suspended work shall hold current, recognized certification (for example, Society of Professional Rope Access Technicians (SPRAT) or Industrial Rope Access Trade Association (IRATA), or an equivalent acceptable to the Owner). The Contractor shall work with the Stone Mountain Memorial Association Public Safety Department to draft a site-specific access and rescue plan and a fall-protection plan for the Owner’s review prior to mobilization. SMMA Public Safety Department should be alerted to all days and times that the Contractor will be on premises. The Contractor shall coordinate all access with the Owner. Comment by Doehrman, Amy: I am not sure if we want to provide any of our equipment Comment by Nic Matthews: I’d suggest no to shield state from liability. Not sure about carving cleaning, but the standard on high rise window washing appears to be the contractor provides platform or suspending scaffolding Comment by Doehrman, Amy: Added this - but does it open us up to liability Comment by Nic Matthews: With the liability provision below, I think we are good here. Naturally, they will need to coordinate with our public safety team to understand mountain access, but as long as we aren’t supplying equipment/mandating they use a certain suspension technique, I think SMMA is shielded.

SCHEDULE AND CONDITIONS

The services are anticipated to commence by September 2026 with anticipated completion in January 2027, when air and surface temperatures are reliably above45°F, and shall not be performed when freezing temperatures are forecast within 72 hours of water application. The Contractor shall coordinate work hours with the Owner and shall observe all event blackout dates and times, including the evening drone and laser show which are listed in Exhibit B. The Owner will provide the confirmed blackout calendar before notice to proceed. The Owner will work with the Contractor to minimize the impact on Park operations and the project delivery deadline. Comment by Doehrman, Amy: Do we want to include this as an exhibit Comment by Nic Matthews: Yes, since they have to present a proposed schedule, we should give the blackout dates as a part of the solicitation Comment by Doehrman, Amy: I added the drone/laser show schedule. We do not currently have blackout dates - should we take that out? Comment by Nic Matthews: I’d leave in for now in case anything does come up between now and then.

QUALIFICATIONS

The Contractor shall demonstrate, at a minimum, the following:

1. At least five years of experience cleaning and conserving historic stone, with at least three completed projects of comparable scale, sensitivity, or access difficulty within the previous five years. Provide project descriptions and owner references.

Cleaning historic masonry: Removal of atmospheric soiling, stains, and biological growth | GSA [1: Cleaning historic masonry: Removal of atmospheric soiling, stains, and biological growth | GSA]

1. A full-time field supervisor experienced in comparable historic-treatment work, present on site whenever work is in progress. The supervisor shall not be changed during the project except for causes beyond the Contractor’s control.

1. If proposing high-pressure steam or laser ablation, documented experience with that specific method on stone of comparable character.

1. All business licenses required in the State of Georgia, workers’ compensation coverage, and the insurance required under Section 8.

INSURANCE REQUIREMENTS

The Contractor shall carry, at a minimum, the following coverage, with the Owner named as additional insured where applicable. Final limits are subject to confirmation by the Owner’s risk office: Comment by Doehrman, Amy: Also, JIA doesn’t put numbers on their construction RFPs from what I can tell

· Commercial General Liability: $1,000,000 per occurrence / $2,000,000 aggregate.

· Automobile Liability: $1,000,000 combined single limit.

· Workers’ Compensation at statutory limits; Employer’s Liability $1,000,000.

· Umbrella / Excess Liability: $5,000,000, as required by the Owner given the work-at-height exposure. Comment by Doehrman, Amy: Is this too low? Comment by Nic Matthews: Can’t find anything for mountain cleaning; but window cleaning association lines up with everything that you listed except they have $1M/$2M for general liability Comment by Doehrman, Amy: Should we make it $1M/$2M

CONTRACTOR RESPONSIBILITY

The Contractor shall exercise the highest degree of care in performing all work on the Carving and surrounding site. The Contractor shall be responsible for protecting the Carving and all adjacent improvements from damage resulting from its operations.

If damage to the Carving or the site occurs as a direct result of the Contractor's operations, negligence, or failure to comply with the requirements of the Contract Documents, the Contractor shall promptly notify the Owner and, upon direction of the Owner, repair or restore the affected area at no additional cost to the Owner. Any repair or restoration shall be performed using methods and materials acceptable to the Owner and, where appropriate, by a qualified stone conservator or other approved specialist.

Changes to the scope of work may be made only through a written modification executed by the Owner's authorized representative.

The contract that the State Entity expects to award will be based upon the RFP, the successful contractor’s final response as accepted by the State Entity and the contract terms and conditions, which terms and conditions can be downloaded from the RFP. The “successful contractor’s final response as accepted by the State Entity” shall mean: the final cost and technical proposals submitted by the contractor and any subsequent revisions to the contractor’s cost and technical proposals and the contract terms and conditions due to negotiations, written clarifications or changes made in accordance with the provisions of the RFP, and any other terms deemed necessary by the State Entity, except that no objection or amendment by a contractor to the RFP requirements or the contract terms and conditions shall be incorporated by reference into the contract unless the State Entity has explicitly accepted the contractor’s objection or amendment in writing.

Please review the State Entity’s contract terms and conditions prior to submitting a response to this RFP. Contractors should plan on the contract terms and conditions contained in this RFP being included in any award as a result of this RFP. Therefore, all costs associated with complying with these requirements should be included in any pricing quoted by the contractors. The contract terms and conditions may be supplemented or revised before contract execution and are provided to enable contractors to better evaluate the costs associated with the RFP and the potential resulting contract.

Any exceptions to the contract must be redlined with comments explaining the rationale for the proposed revision, uploaded and submitted as part of the contractor’s response, and should be provided as a red-line markup of the posted contract with inserted comments specifying the need for the changes. In the event the contractor is selected for potential award, the contractor will be required to enter discussions with the State Entity to resolve any contractual differences before an award is made.

PROPOSAL SUBMISSION REQUIREMENTS

All proposals shall include the following, organized in the order listed:

· A cover letter signed by an individual authorized to bind the firm.

· A firm overview, relevant experience, and at least three references for comparable historic-stone or monument cleaning projects.

· A proposed approach and methodology, including the specific cleaning methods, products (with technical data sheets and Safety Data Sheets), equipment, water pressures, and a test-panel plan for each surface and soiling type.

· A site-specific access plan, fall-protection plan, and proposed rescue plan, with the certifications of personnel performing work at height.

· Key personnel and field-supervisor qualifications.

· A project schedule covering mobilization, test panels, cleaning, and closeout.

· An itemized cost proposal within the budget stated in Section 4, including any unit pricing for optional or supplemental methods (e.g., steam or laser areas).

· Certificate(s) of insurance evidencing the coverage required under Section 8.

· All required forms and certifications identified by the Owner Comment by Doehrman, Amy: What all do we require? Comment by Nic Matthews: At minimum, I’d think we would need to see the certifications you mentioned above related to rope and suspended work. Also, some boiler plate info on eVerify, drug free work place etc. Comment by Christian Hamby: Agreed with Nic, the procurement manual does not have a universal set of forms that every RFP solicitation must include, just depends on the particular state entity's solicitation request like for this project a suspended work certification

Proposals are due no later than 5:00PM EST on August 12, 2026. and shall be submitted as directed there. Late proposals will not be accepted. Submissions should be sent to procurement@stonemountainpark.org with all requirements combined into one PDF document. Physical copies of submissions are not needed and will not be accepted. Questions must be submitted in writing to procurement@stonemountainpark.org; responses will be issued to all known proposers by addendum.

EVALUATION CRITERIA

The Owner reserves the right to reject any or all proposals, to waive informalities, and to make the award determined to be in its best interest. Lowest cost will not be the sole basis of award, and any proposal that relies on a prohibited method will be deemed non-responsive. The following are the general factors Stone Mountain Memorial Association will consider:

· Relevant experience and references (comparable historic stone/monument work) Comment by Doehrman, Amy: Do we need to add scoring percentages Comment by Nic Matthews: Unsure if required. I don’t think we provided a breakdown up front for vendor selection for the whole park. Comment by Christian Hamby: I think listing our evaluation methodology is required but we don’t have to publicly disclose our percentages or scoring criteria

· Cleaning methodology and project timeline

· Access, safety, and proposed rescue plan for work at height

· Qualifications of key personnel and field supervisor

· Cost of project

Contractor RFP Instructions

RFP SUBMISSIONS AND AMEND

The Stone Mountain Memorial Association reserves the right to reject all proposals submitted in response to this request. Furthermore, SMMA reserves the right to amend the RFP prior to the date of proposal submission. Amendments will be sent to all Offerors who originally received a copy of the RFP.

PROPOSAL WITHDRAWL

Prior to the proposal due date, a submitted proposal may be withdrawn by the Contractor by submitting a written request to the Issuing Officers named herein. All such requests must be signed by a person authorized to sign for the Contractor.

COST FOR PREPARING PROPOSALS

The cost for developing the proposal is the sole responsibility of the Contractor. The SMMA will not provide reimbursement for such costs, nor for related legal and travel fees.

LIABILITY PROVISIONS

When Contractor enters or goes onto SMMA property to inspect the Carving or prepare the proposal, Contractor does so at its own risk and expense. By submitting a Proposal, Contractor hereby agree to indemnify, defend and hold harmless SMMA, the State of Georgia and its departments, agencies and instrumentalities and all of their respective officers, members, employees and directors (hereinafter collectively referred to as the “Indemnitees”) from and against any and all claims, demands, liabilities, losses, costs or expenses, including attorneys’ fees, due to liability to a third party or parties, for any loss due to bodily injury (including death), personal injury, or property damage, including but not limited to intellectual property claims, arising directly or indirectly from the submission of a proposal, including any Inspections, by the Contractor or its agents, employees, associates, subcontractors or others working for or on behalf of Contractor

COMPLAINCE WITH GEORGIA STATE LAW

The Contractor shall comply with all applicable federal, state, and local laws, rules, and regulations, including all laws of the State of Georgia, in the performance of this RFP and any resulting contract. Submission of a proposal constitutes the Contractor’s representation that it is fully knowledgeable of, and in compliance with, all such legal requirements. Failure to comply may result in disqualification or termination of any contract.

DISCLAIMER

Information contained in any exhibit of this RFP is provided for information purposes only and is not warranted as accurate by the SMMA. Each Contractor making a proposal should exercise its own due diligence to ascertain the information on which it chooses to base its proposal.

EXHIBITS

Exhibit A: SMMA 2025 Annual Monitoring Report

Exhibit B: 2026 Drone/Light Show Dates

Exhibit C: 2017 Cleaning Site Test

Exhibit D

Exhibit E: Contractor Affidavit

Exhibit F: Contract image1.emf

STONE MOUNTAIN MEMORIAL CARVING

ANNUAL MONITORING REPORT

October 2025

Prepared by Larry Winslett for the Stone Mountain Memorial Association

MONITORING PLAN FOR STONE MOUNTAIN MEMORIAL CARVING

ANNUAL CHECK LIST FOR 2025

WHAT PHOTO

Inspection

PHYSICAL

Inspection

FINDINGS AND NEEDED OR RECOMMENDED ACTIONS

Spring 4/25, Fall 9-10/25 Spring/Fall S F S F

EXFOLIATION

General

Y Y N N No significant changes (see pg. 6 for Jackson forehead)

VEGETATION

Around/On Carving

Y Y N N New growth continues to accelerate, see page 8.

Vegetation growth (trees and grasses) on the tablet area, above and below the carving, is becoming increasingly significant.

LICHEN GROWTH

Figures/Tablet

Y Y N N Lichen growth continues to be an increasing aesthetic problem.

(See note below about cleaning test sites.)

DUTCHMEN

JACKSON

Y Y N N No Significant Change observed, see pg. 6 Caulking on beard and collar needs to be watched.

Forehead patch still looks good!

LEE

Y Y N N No Significant Change observed, see pages 5 & 7.

Lichen growth in Lapel area showing significant increase (pg 5.)

DAVIS & HORSES

Y Y N N Caulking on Davis’ hat still needs to be watched, no visible deterioration from 2024. See pg 5.

LOOSE ROCK, ETC

(Above Carving Below Fence)

Y Y Y Y Increase in debris sighted, trash & loose small rocks. Observed from the lawn below, the skylift and above at fence line.

WATER DIVERSION

WALL

(Mountain Top)

Y N Y Y No Significant Change observed. Page 10 reference photo.

JACKSON Forehead Patch Exfoliation

Y Y N N No Significant Change observed. (see page 6) Note: Patch still looks good, no changes observed.

WHOLE TABLET

ANNUAL PHOTOS

Y Y NA NA Photographed for future comparison and review (see page 3)

CARVING FIGURES

Y Y NA NA Photographed for future comparison and review (see page 3)

FULL MOUNTAIN

VIEW

Y Y NA NA Photographed for future comparison and review (see page 4) Note: Vegetation below carving shows increasing new growth.

SUMMARY/COMMENTS: Observations made per adopted (2016, rev. 2019) monitoring plan. No specific new issues observed at this time, carving appears to remain structurally sound, only usual aesthetic issues of vegetation, lichen, and some loose rock and trash above noted. Cleaning test sites are on pages 8 & 9. All cleaning sites (origins in 2016/17) now show almost total decline regardless of method used. It should be noted that the high pressure steam plus chemical seem to be hold up best. This is especially true in areas receiving direct or significant water flow. Note: Full Hi-RES images can be viewed as needed and will be added to the catalog of images with annual LM updates.

Prepared for SMMA by L. Winslett 4/2025 & 9-10/2025

Full Tablet View

Full Carving View

Full Mountain Face

Close-up View of Base Vegetation

Traveler Dutchman

Davis Dutchman

Lee’s Lapel Dutchman

Jackson Exfoliation and Dutchman

Lee’s Dutchman

Tablet Vegetation & Cleaning Test Site (see pg. 10)

Above Tablet Vegetation & Jackson Cleaning Test Site

Area Above Tablet

Cleaning test sites, Quarry area adjacent to skylift parking lot. All now in significant decline.

Major rain run-off locations. Diversion wall at top still appears to help.

(2024 Photo for flow reference.) 10

Cleaning test site (on tablet below Jackson), now in significant decline.

CARVING CONTACTS

Duane Studdard, SMMA 770-498-5679 d.studdard@stonemountainpark.org

Mark Lassiter (physical inspections) 828-526-4044 mllwhiteside@gmail.com

Larry Winslett (annual photographic inspections and maintaining documents) 404-375-8405 winfog@windstream.net

Rich Barry (consultant on repairs and cleaning) 605-673-5643 605-440-3121 rich.barry@gwtc.net

Josh Griffith, SMMA (Land Management Committee Chair/Education) 404-538-0458 j.griffith@stonemountainpark.org

Donna Faulkner (historic information on Roy Faulkner) 678-908-3555 image2.emf

2026 DRONE/LIGHT SHOWS

(subject to change)

Lunar New Year February 14, 15, 21, 22, 28; March 1

- Only available with a Lunar New Year Festival ticket; no snack terraces

DinoFest March 7, 14, 21, 28; April 4, 5, 6, 7, 8, 9, 10, 11, 18, 25

Music Across America May 2, 9, 16, 22, 23, 24, 25, 29, 30, 31; June 4, 5, 6, 7, 11,12, 13, 14, 25, 26, 27, 28; July 1, 2, 3, 4, 5, 6, 9, 10, 11, 12, 16, 17, 18, 19, 23, 24, 25, 26, 30, 31; August 1

- no Drone & Light Show Mondays-Wednesdays in June and July, except Monday, July 6

- extra fireworks May 22-25 and July 1-6

- Music Across America show will be FREE in June

Lift Every Voice (FREE) June 18, 19, 20, 21

Classic Lasershow (FREE) August 8, 15, 22, 29; September 5, 6, 7, 12

- extra fireworks Sept 5-7

Pumpkin Festival September 19, 20, 21, 25, 26, 27; October 2, 3, 4, 9, 10, 11, 12, 16, 17, 18, 23, 24, 25, 30, 31; November

- Only available with a Pumpkin Festival ticket; no snack terraces

Stone Mountain Christmas November 7, 8, 14, 15, 21, 22, 23, 24, 25, 26, 27, 28, 29; December 4, 5, 6, 11, 12, 13, 18, 19, 20, 21, 22, 23, 24, 26, 27, 28, 29, 30, 31; January 1, 2, 3 (2027)

- Only available with a Christmas ticket; no snack terraces image3.emf

1 / 29

Confederate Memorial Carving

Stone Mountain, Georgia - USA

Inspection and Test Cleaning Report

Authors: Alfred Kärcher GmbH & Co. KG Nick Heyden / CPR Alfred-Kärcher-Straße 28-40 71364 Winnenden Germany

Rich Barry/Consultant-Karcher US Project

March 2018

2 / 29

Contents

1.0 Executive Summary 03

2.0 Monument Description 05

3.0 Problem Analysis 06

4.0 Test Cleaning and Performance Analysis 08

4.1 Test 1-First Test Cleaning at the Quarry 09

4.2 Tests 2 / 3-Test Cleaning on the Carving 13

4.3 Test 4-Second Test Cleaning at the Quarry 21

5.0 Cleaning Recommendations 24

6.0 Industrial Rope Access 25

3 / 29

1.0 Executive Summary

In October 2017 Karcher, Ropeworks and SMMA conducted a cleaning test as a com-ponent of ongoing efforts to preserve the Memorial.

Biological soiling (growth) naturally persists on the Memorial’s stone surface and sub-surface, through naturally occurring pores/fractures or damage from the carving pro-cess. This soiling can have a long term detrimental physical and visual effect on the Memorial. Removal (cleaning) of the soiling helps slow the effects of the natural ero-sion processes on the stone.

Background Since cosmetic stone damage was discovered in Spring 2015 on Stonewall Jackson.

Karcher has been assisting SMMA with expertise in conservation and cleaning of stone. Rock samples were collected March 28-31, 2016 and analyzed by Dr Gabriele Grassegger-University of Applied Sciences Stuttgart-Laboratory for Building Chemis-try. Biological samples were collected December 4, 2015 and analyzed by Dr Stefanie Scheerer-BioPhil-Microbiology in Restoration. Dr Grassegger later provided additional guidance on cleaning, repairing and conserving the damaged areas.

Testing SMMA has been exploring two methods to safely and thoroughly clean the Memorial.

Variable temperature-pressure water and D/2 Biologic Solution. Cleaning tests with D/2 have previously been conducted in July and October 2016 at the Quarry and in March 2017 on the tablet below the figures. The October 2017 tests were designed to compare, side by side, the cleaning effectiveness of both methods. Four tests were executed in the following sequence: Quarry, Top of Memorial, Base of Memorial and Quarry.

Results The water temperature-pressure achieved at the carving, with equipment staged at the base of the Memorial, proved successful in safely and thoroughly cleaning the biologi-cal growth from the stone. To achieve similar results with D/2 the use of “work inten-sive” brushing and rinsing with water was required.

Considerations As part of preparations for cleaning there are several actions that should be consid-ered in advance: reducing (diverting) water flow over the Memorial, remediation of the superficial stone damage on Stonewall Jackson and understanding how much of the figures and tablet should be cleaned.

With the large surface area above the Memorial signifanct amounts rain water collect and drain down over the carving. This increases the moisture in and on the stone ac-celerating biological growth and regrowth.

The cosmetic stone damage on the surface of Stonewall Jackson is fragile and very susceptible to further damage. It may require treatment with preservation based reme-diation techniques to prevent further possible damage associated with cleaning.

4 / 29

To achieve the preservation and artistic goals for the Memorial how much of the fig-ures and tablet should be cleaned will need to be determined. Biological growth above the carving will have some undetermined reseeding effect on recolonizing the cleaned stone. What is cleaned and not cleaned will have a visual impact on the artistic ap-pearance of the Memorial.

Conclusion Cleaning the Memorial using the variable temperature-pressure water method is an effective, efficient and minimally invasive approach following the highest international preservation standards. The steam temperature achieved during the testing removed the biological soiling on the stone’s surface with minimal abrasiveness and kinetic en-ergy. The subsurface biological growth will also be eliminated at this cleaning tempera-ture.

It should be noted that gentle cleaning with pure water alone, when possible, is gener-ally preferred over chemicals by many preservation experts. There is always some risk for chemicals to have an unintended adverse reaction with the stone.

5 / 29

2.0 Monument Description

Name: Stone Mountain Confederate Memorial

Address: Stone Mountain Memorial Association 1000 Robert E Lee Blvd Stone Mountain

GA 30083

USA

Material: Granite

Contact: Bob Cowhig Director Planning and Construction 770 498-5714 (phone) 770 498-5610 (fax)

Performance by: Alfred Kärcher GmbH & Co. KG Nick Heyden Cultural Sponsoring Restorative Cleaning Projects Alfred-Kärcher-Str. 28-40 71364 Winnenden

Performance on: 23rd of October to 26th of October 2017

6 / 29

3.0 Problem Analysis

The carving of the Stone Mountain Confederate Memorial was finished in 1972 and is generally in a good condition with the exception of the localized cosmetic damage on Stonewall Jackson. For more details see Dr. Grassegger’s Reports.

Dr. Grassegger Report: October 11th, 2016 - Investigation Report Stone Moun-tain, USA

Dr. Grassegger Report: May 18th, 2017 – Renovation of Historic Monuments and Old Buildings)

With the warm humid regional climatic conditions biological soiling (growth) like algae, fungi and lichen flourish on the granite. Wide spread soiling persists across the Memo-rial. The dark colored biological soiling is clearly visible on the light colored granite.

In addition to the general climate conditions the significant surface area above the carving collects large volumes of rain water. The water is channeled into consistent drainage patterns down the face. During and after rain events the carved surface is exposed to moisture for prolonged periods of time as the water drains from the areas above. The different degrees of biological soiling are dependent on the water drainage concentrating at different points.

Biological soiling can play a role in the natural erosion process of the stone. The growth of the algae, fungi and lichen on and into the stone can have a detrimental ef-fect on the Memorial beyond visual appearance. For further details on the detrimental effect of biological growth on stone see Dr. Scheerer’s Report.

Dr. Scheerer Report: March, 2017 - Microbiological Investigation of Rock Sam-ples from Stone Mountain, Georgia, USA).

7 / 29 pic. 01: Overview of the Stone Mountain Confederate Memorial.

pic. 02: Visible concentrated traces of water drainage.

8 / 29

4.0 Test Cleaning and Performance Analysis

Testing was required to determine if the variable temperature-pressure water cleaning method could be used to clean the Memorial. Four tests were devised to answer three basic questions.

What is the effectiveness of variable temperature-pressure water compared with the D/2 cleaning method to safely and thoroughly remove the biological soiling from the stone?

With equipment staged at the top or base of the Memorial can a high enough water temperature (primary) and pressure (secondary) be achieved to safely and thoroughly remove the biological soiling from the stone?

Will the proposed industrial rope access techniques safely and efficiently deploy high pressure hose and personnel to the carving?

The four tests were conducted between October 23 through 25, 2017 in the following sequence.

Test 1 Quarry: Compare maximum water temperature (310 F steam at 7-10 psi) and D/2 cleaning methods.

Test 2: Monument Top: Test cleaning effectiveness of “achievable” water tem-perature-pressure at the carving.

Test 3: Monument Base: Test cleaning effectiveness of “achievable” water tem-perature-pressure at the carving.

Test 4: Quarry: Compare “achievable at the carving” water temperature-pressure and D/2 cleaning method.

9 / 29

4.1 Test 1-First Test Cleaning at the Quarry

Compare the optimal cleaning parameters of the HDS-Superclass machine with previ-ous D/2 testing. The steam temperature for this test cleaning was 310° Fahrenheit.

The cleaning was executed using pure water only. No chemicals or detergents were utilized in the test.

Machine type: HDS 5.0/30-4S

Nozzle type: 40° steam nozzle

Surface pressure: 7 - 10 psi (0.5 - 0.7 bar)

Temperature: 310° F (155 °C)

Surface: Granite

Location: Quarry pic. 06: 310° F steam cleaning (October 23, 2017) compared with D/2 Test

16-24 (Spray application and brush - July 26, 2016).

D2 Test Panel

Steam Clean Panel

10 / 29 pic. 07: 310° F steam cleaning - left (October 23, 2017) compared with D/2

Test 16-25 (First spray application - July 26, 2016 and second spray application - October 6, 2016). Note rock was still wet when photo was taken.

11 / 29 pic. 08: 310° F steam cleaning - right (October 23, 2017) compared with D/2

Test 16-25 (First spray application - July 26, 2016 and second spray application - October 6, 2016).

12 / 29 pic. 09: 310° F steam cleaning (October 23, 2017) compared with D/2 Test

16-26 (First spray application - July 26, 2016 and second spray ap-plication - October 6, 2016).

Performance analysis steam cleaning:

The 310° F steam cleaning method appears to have an initial “cleaner result” over what was achieved with the D/2 methods tested. To understand the impact of either method on the rate at which the biological soiling will regrow requires a longer term study.

13 / 29

4.2 Tests 2 / 3-Cleaning Tests on the Carving

Identify which HDS-machine could produce the water temperature and pressure re-quired to gently remove the biological growth. Heated pressurized water pumped through high pressure hose loses temperature and pressure as distance increases and elevations change. Testing was required to quantify the exact perimeters that could be achieved when pumping heated pressurized water from the top and then base of the Memorial to the carving.

Three different hot water high-pressure cleaning machines were tested to identify the most suitable machine and equipment staging location.

Machine types: HDS 1000 De, HDS 4.5/22-4M, HDS 5.0/30-4S

Nozzle type: 40° steam nozzle

Surface pressure: 7 - 10 psi (0.5 - 0.7 bar)

Temperature: 70 - 310° F (20 - 155 °C)

Surface: Granite

14 / 29 pic. 10: Areas where the test cleaning on the carving took place.

pic. 11: Close ups of the test areas.

15 / 29 pic. 12: Positioning with the rope access to reach the upper test area.

pic. 13: Test cleaning with the steam.

16 / 29 pic. 14: Steam cleaning Stonewall Jackson on torched-pneumatically chiseled “fin-ished” surface left and torched only surface right (October 24-25, 2017).

17 / 29

Test Panel 1:

Machine type: HDS 1000, Staged on the top

Temperature: 140° F (60°C) with 1000 feet (300m) HD-hose

Test panel 2:

Machine type: HDS 4.5/22-4M, Staged on the top

Temperature: 172° F (78°C) with 1000 feet (300m) HD-hose

Test panel 3:

Machine type: HDS 1000, Staged at the base

Temperature: 200° F (93°C) with 500 feet (150m) HD-hose

Test panel 4:

Machine type: HDS 5.0/30-4S, Staged at the base

Temperature: 232° F (111°C) with 500 feet (150m) HD-hose

Test panel 5:

Machine type: HDS 4.5/22-4M, Staged at the base

Temperature: 221° F (105°C) with 500 feet (150m) HD-hose

18 / 29 pic. 15: Steam cleaning (October 24-25, 2017) compared with D2 Test on tablet

(spray application and brush left and spray application right – March 29, 2017)

D2 test panel-spray/brush D2 test panel-spray only

19 / 29

Test Panel 6:

Machine type: HDS 1000, Staged on the top

Temperature: 149° F (65°C) with 1000 feet (300m) HD-hose

Test panel 7:

Machine type: HDS 4.5/22-4M, Staged on the top

Temperature: 167° F (75°C) with 1000 feet (300m) HD-hose

Test panel 8:

Machine type: HDS 1000, Staged at the base

Temperature: 198° F (92°C) with 500 feet (150m) HD-hose

Test panel 9:

Machine type: HDS 5.0/30-4S, Staged at the base

Temperature: 232° F (111°C) with 500 feet (150m) HD-hose

Test panel 10:

Machine type: HDS 4.5/22-4M, Staged at the base

Temperature: 221° F (105°C) with 500 feet (150m) HD-hose

20 / 29

We were able to achieve the best and most gentle cleaning results for the removal of biological soiling on the granite with the following device settings and parameters.

Hot water high-pressure cleaner HDS 5.0/30-4S in the steam mode (halved wa-ter quantity) with special and gentle steam nozzle.

The best result was achieved when the machine was placed at the base of the Memorial with 500 feet of high pressure hose leading up to the test areas.

The pressure on the surface with a steam nozzle is approximately 7 - 10 psi (0.5 - 0.7 bar) at a distance from 6 inches (15 cm).

The water temperature 232° F (111°C) reached on the carving will sustainably kill biogenic residual particles and spores in the pore space of the rock and sig-nificantly retard resettlement.

21 / 29

4.3 Test 4-Second Cleaning Test at the Quarry.

Demonstrate the parameters achieved on the carving with the HDS-Superclass ma-chine. The temperature for this test cleaning was 232° Fahrenheit. The testing includ-ed utilizing steam and D/2 to provide a comprehensive over view of both methods.

pic. 16: 232° F steam cleaning combined with D/2 (October 25, 2017).

A B C

22 / 29

Test Panel A:

Machine type: HDS 5.0/30-4S

Nozzle type: 40° steam nozzle

Temperature: 232° F (111°C)

D2-biocide: None

Test panel B:

Nozzle type: 40° steam nozzle

D/2 Biologic Solution: Spray application before steam cleaning

Test panel C:

Nozzle type: 40° steam nozzle

D/2 Biologic Solution: Spray application after steam cleaning

23 / 29 pic. 17: Red: D/2 test panels (November 17, 2017) - Yellow: 232° F Steam cleaning combined with D/2 (October 25, 2018).

Test Panel D: D/2 spray application

Test panel E: D/2 spray application and brush

Test panel F: D/2 spray application, brush and water rinse

The 232° F steam cleaning method appears to have a visually similar result to the ini-tial 310 ° F tests results. Appling D/2 in advance of cleaning with steam does not pro-duce an apparent improvement in cleaning effectiveness. D/2 spray application with brushing and water rinse appears to produces a visually similar result to steam. To understand the impact of steam, D/2 and the combining both on the rate at which the biological soiling will regrow requires a longer term study.

Comparing the abrasiveness of D/2 spray application with brushing and water rinse to steam cleaning, steam at 7-10 surface psi is generally believed to be gentler on the stone. Stream cleaning is also a more efficient cleaning method over brushing and rinsing. Cleaning with pure water does eliminate any risk for an adverse chemical-stone interaction.

D E F

24 / 29

5.0 Cleaning Recommendation

For the gentle removal of biological soiling steam cleaning is the best approach from a preservation restoration perspective. A temperature greater than 176°F (80°C) can sustainably kill biological growth by modifying the molecular structure of the cell‘s pro-tein. Cleaning the Memorial with 232 °F steam will remove the biological soiling on the surface with minimal abrasiveness and kinetic energy. Subsurface growth, residing deeper inside the pores of the stone, will be eliminated, extending the time it takes for new growth to recolonize the stone.

After analyzing the test results to remove the algae, fungi and lichens from the Stone Mountain Confederate Memorial granite we recommend the following.

Equipment Specifications:

Super class HDS 5.0/30-4S hot water high-pressure cleaner

Steam mode with maximum reachable temperature 232 °F

40° steam nozzle

Surface pressure 7 - 10 psi (0.5 - 0.7 bar) at a distance from 6 inches (15 cm)

Equipment staged at the base of the Memorial

8 mm HDS high pressure hose

Water consumption rate up to 2.5 gallons per minute

Project Personnel:

Two cleaning experts

Three to four rope access technicians

Three superclass hot water high-pressure cleaner running at the same time

SMMA support personnel and equipment to assist as needed

SMMA security personnel stationed at the top and base

Project Duration:

Execution will be approximately ten working days to clean the carved surface.

Cleaning out into the tablet area will require additional time.

Back up days are not included.

Project Access:

Industrial rope access to all points on the carving

Set up times to be determined

25 / 29

6.0 Industrial Rope Access

Industrial rope access techniques were planned and utilized to position personnel and equipment on to the Carving for the cleaning test.

Additional anchors were installed and remain in place for future use.

Ropes were deployed from the top of the Memorial reach the test areas and the Memorial base.

The high pressure hoses were pre-connected into a single continuous length and laid out in zig-zag pattern on the visitor side of the security fence at the top.

The hose was manually lowered down the face alongside the rope access an-chors using a…