1	Investigating Fire Suppression Impacts on Historic Resources Lessons learned from the Long Mesa Fire of 2002
2	Mesa Verde Historic Districts Administrative Area National Historic Landmark* CCC Camp Historic District* Navajo Hogan Area Historic District* Residential ‘White House’ and Utility Area Historic District* Campground Area Historic District Morefield Village (Mission 66 Eligible) * Impacted by Long Mesa Fire ‘02
3	Administrative ‘Headquarters’ Area National Historic Landmark
4	Residential Area ’White House’ Historic District
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6	Fire Progression July 29, 2:50 pm – 3:30 pm
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9	Fire and Suppression Impact Summary Two Historic Structures completely destroyed by fire, one damaged Fifty-Five Building Interiors in Five Historic Districts damaged by ash, soot and smoke debris; eighteen considered severe Twenty-Three Building Exteriors in Two Historic Districts impacted by heavy applications of fire retardant A total of one Acre of land clear-cut within the Administrative National Historic Landmark District 300 gallons of Barricade Polymer Gel used in Three Historic Districts 106,628 gallons of Firetrol (slurry) was dropped from Air Tankers over Historic Districts 110,000 gallons of PhosCheck (slurry) was dropped from Helicopters
10	Barricade Gel Liquid Concentrate of absorbent polymers (potassium polyacrylate); surfactants Sticks to vertical and horizontal surfaces “Glues” water to the sides of buildings Powerful Dessicant Eye and Skin Irritant Extremely slippery when wet
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15	Fire-Trol LCA-R/Phos-Check D-75 Slurry Monoammonium Phosphate Ammonium Sulfate Iron Oxide Coloring Agent Clay Thickener *Sodium Ferrocyanide (Fire-Trol) Concerns: Can be toxic in concentrations Slightly acidic Highly Corrosive- Zinc, Magnesium based metals are worst ; Aluminum, Brass, Steel are least affected Permanent Staining Clay deposits can trap water Introduces phosphates (soluble salts) into pores
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33	Observed Retardant Impacts Polymer Gel: Stripping of Surface Finishes Sandstone damage Dessicant Slurry: Iron Oxide Staining Corrosion of Metals Soluble Salt Deposition – Efflorescence Clay Deposition – Water entrapment Sandstone spalling in long term observations
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48	Retardant Cleaning Procedures Recommended: Dry Brushing Hand Brushing w/ water Hand Brushing w/ Alkaline Surfactants Poulticing NOT Recommended: Power Washing Sandblasting Acid Based Washes Sandstone Pre-soak w/ water 10% borax solution (surfactant) Gentle circular brushing w/ natural fiber Rinse w/ water Repeat where necessary * Painted Wood: Pre Soak w/water Brushing w/ mild detergent Rinse Metals, Glass: Wipe or Sponge w/ mild detergent Wipe Dry
49	What NOT to Do: This will drive the chemicals further into the porous rock, and damage rock features.
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58	Summary of Retardant Investigations Retardants pose potential risks to health, safety & cultural properties. Retardants will not wash off naturally - they require intervention to remove, particularly on vertical surfaces Mitigative measures were tested that effectively removed retardants w/out further damage to cultural resources
59	Strategies for Retardant Impacts Mitigation Assess Impact - Resource Type, Retardant Type Research Retardant Type and MSDS Evaluate Risk to Resources Mitigate impacts where necessary Map affected areas Establish monitoring system Consider integrating potential suppression impacts into Fire Management Plan