Carson Dorn, Inc. December 18, Patrick Holmes Associate Manager Juneau I, LLC 645 G Street, Suite Anchorage, AK Dear Mr.

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1 Carson Dorn, Inc. 712 West 12th Street Juneau, Alaska 9981 December 18, 212 Patrick Holmes Associate Manager Juneau I, LLC 645 G Street, Suite 1-64 Anchorage, AK 9951 Dear Mr. Holmes, The renovation of the Department of Labor Building in Juneau began on October 23, 212. The building is scheduled for a full renovation, phased to allow occupancy of approximately ¾ of the building and renovation of approximately ¼ of the building at a time. Demolition in each phase will include removal of wallboard, vapor barrier, fiberglass insulation, carpet, and ceiling tiles from the office areas, complete replacement of finishes and fixtures in the restrooms, and replacement of the HVAC system and much of the supply and return air ducting. As part of the build-back, additional windows are being added to the building to increase the natural light in the work areas. A phasing diagram is attached for reference. Wallboard removal in the Phase 1 area (2/3 of the third floor) occurred from October Wall cavities and above-ceiling space were inspected for the presence of mold and rot and signs of water intrusion. All demolition was done with negative air machines in use, keeping the work area under a slight negative pressure to assure that all construction dust was filtered and vented to the outdoors rather than allowed to move into the occupied office space. Very little mold was found (slight shadowing on two 1-square foot areas), no structural deficiencies were found, and all wall cavities were dry. Staining was evident from historic water intrusion problems before the siding upgrade in 28. All stained areas were cleaned with a detergent solution in accordance with the DOL Building Renovation Work Plan (attached), which follows current guidance from the industrial hygiene field. On October and October 29-31, 212, Meribeth Geiger, Associate Environmental Professional at CDI collected daily air samples for airborne mold on the 3 rd floor of the Department of Labor Building. Additionally, from October 23-November 19, CDI conducted real-time monitoring for relative humidity, temperature, carbon dioxide (CO 2 ), and particulates Tel: Fax:

2 Carson Dorn, Inc. 712 West 12th Street Juneau, Alaska 9981 (PM 1 ). The sample collection location (the third floor elevator lobby) was the only exterior entry to the occupied third floor office space during construction, and is located adjacent to the construction area. Air samples for spore counts were collected using Allergenco-D TM cassettes (37-mm diameter) using a 12 volt AC high volume sampling pump (primary calibrated in the field) to draw 15 liters of air per minute for 1 minutes per sample. The samples were analyzed by ALS Environmental using Method MC-AN-1. Fungal spore counts were determined using plain light microscopy under 63x magnification. 1% of the entire sample slide was read. Individual spherical spores lacking any distinguishing characteristics may be grouped and classified under the category Amerospores. Total fungal spore particulate concentrations include both viable and non-viable counts. The calculated total count is based on the trace length and microscopic field diameter, as recommended and described as correct methodology by the manufacturer of the spore trap cassette. Individual spore counts greater than 4 are based on estimates, due to the higher density rating. Spore counts for each day are shown in Table 1. Air samples are typically evaluated by means of fungal type identified and by comparing indoor and outdoor concentrations, complaint to non-complaint areas, or area of concern to areas of nonconcern. In general, the levels and types of fungi in the indoor air should be similar to or lower than those found in the outdoor air. Higher levels of spores (order of magnitude) found inside may indicate that moisture sources and resultant fungal growth are present. Spore count results are influenced by geographic location, seasonal and diurnal variation, and biotic /abiotic outside conditions. Certain fungi are very good indicators of water damage. The presence of these spores, even in small quantities, can indicate the presence of water damage. The genus of the mold spores and total spore counts for each sample, as well as the airborne concentration in spore counts/cubic meter, is provided in the analytical report (enclosed herewith). The test results provide an indication of the genus of mold but do not differentiate the species of mold within the particular genus. Air results are summarized in Table 1. Fungal spores are found everywhere. Whether or not symptoms develop in people exposed to fungi depends on the nature of the fungal material (e.g., allergenic, toxic, or infectious), the exposure level, and the susceptibility of exposed persons. Susceptibility varies with the genetic predisposition (e.g., allergic reactions do not occur in all individuals), age, pre-existing medical conditions (e.g., diabetes, cancer, or chronic lung conditions), use of immunosuppressive drugs, and concurrent exposures. These reasons make it difficult to identify dose/response relationships that are required to establish safe or unsafe levels (i.e., permissible exposure limits). There are no regulatory exposure limits for mold spores, but guidelines have been proposed by the mold abatement industry. The Standard and Reference Guide for Professional Mold Remediation (IICRC S52) has compared symptoms in mold spore allergy sufferers to mold spore counts, and reports that spore counts below 6,5 spores per cubic meter of air are considered low and should provoke symptoms only in individuals extremely sensitive to mold spores (IICRC S52,Tables 3 and 4). Samples collected from all days show spore counts no higher than 8 spores per cubic meter, and four of the seven days had total spore counts below 3 spores per cubic meter. Tel: Fax:

3 Carson Dorn, Inc. 712 West 12th Street Juneau, Alaska 9981 Sample ID DOL-PH1-1 October 23 Table 1. 3 rd Floor Elevator Lobby Air Sample Summary Department of Labor Building Juneau, Alaska October 23-29, 212 Spore Type (count/m 3 Sample ID Spore Type ) Ascospores Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes DOL-PH1-5 October 27 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes (count/m 3 ) DOL-PH1-2 October 24 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes DOL-PH1-6 October 28 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes DOL-PH1-3 October 25 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes DOL-PH1-7 October 29 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes DOL-PH1-4 October 26 Aspergillus/Penicillium Basidiospores Cladosporium Stachybotrys Smuts/Myxomycetes Real-time monitoring data for, humidity, temperature, CO 2, and particulates were downloaded weekly. Average values for October 23-November 19 were: Average Relative Humidity = 19.7% Average Temperature = 22 C Average CO 2 concentration = 168 ppm Average Particulate (PM 1 ) concentration =.125 mg/m 3 Daily values are found in Table 1, along with indoor air quality standards for comparison. A discussion of each air quality parameter follows. Tel: Fax:

4 Carson Dorn, Inc. 712 West 12th Street Juneau, Alaska 9981 Date Table 2 Daily Average Air Quality Measurements for Oct 23-Nov 19, 212 DOL Building, 3 rd Floor Elevator Lobby Humidity Temp CO2 PM-1 % C ppm mg/m3 1/23/ /24/ /25/ /26/ Comments 1/27/ High winds/saturday 1/28/ No work/sunday 1/29/ High winds 1/3/ /31/ /1/ /5/ /6/ /7/ /8/ /9/ /14/ /15/ /16/ /17/ /18/ No work/sunday 11/19/ AVG Recommended 3-5 ~22.5 <1, <.15 Relative humidity in the building ranged from 14.9% to 28.7%. There is no ideal humidity level suitable for all building occupants. The American Society of Heating, Refrigerating and Air-conditioning Engineers Inc. (ASHRAE) recommends humidity levels range from 2% to 6% year-round. Levels less than 2% in the winter and greater than 6% in the summer should be considered unacceptable. Elevated relative humidity can promote the growth of mold, bacteria, and dust mites, which can aggravate allergies and asthma. Low humidity can lead to dehydration and discomfort of the skin and respiratory systems. Humidity levels in this building are lower than the recommended range. Daily temperature ranged from 13.8 C to 26.9 C. There is no ideal temperature suitable for all building occupants. ASHRAE recommends that indoor temperatures in the winter be maintained between 2 degrees and 24 degrees and temperatures in the summer should be maintained Tel: Fax:

5 Carson Dorn, Inc. 712 West 12th Street Juneau, Alaska 9981 between 23 degrees and 26 degrees. Note that the sample location was in the elevator lobby, near the stairwell, which is generally cooler in temperature than the office areas. The measured values fall slightly below the recommended temperature, but the perceived temperature in the building is generally somewhat higher than the recommended value. CO 2 ranged from 67 ppm to 368 ppm. The outdoor level of carbon dioxide is usually from 3 parts per million to 4 parts per million (ppm). If indoor carbon dioxide levels are more than 1, ppm (ASHRAE), there is probably inadequate ventilation; and complaints such as headaches, fatigue, and eye and throat irritation may be prevalent. An elevated carbon dioxide level is an indication of an inadequate amount of outside air being brought into a building. CO 2 measurements are extremely low in this building, and possibly indicate an iniability of the equipment to detect CO 2 accurately. However, past measurements of CO 2 in the building indicate that the levels are generally similar to those for outdoor air. For future reference, CO 2 will also be tracked with additional equipment for comparison. Particulates from 2.5 micrometers to 1 micrometers in diameter (PM 1 ) ranged from. mg/m 3 to.166 mg/m 3. The USEPA National Ambient Air Quality Standard (NAAQS) recommends that PM 1 be maintained at less than.15 milligrams of particulates per cubic meter of air (mg/m 3 ). OSHA classifies particulates as either respirable (less than 5 microns in diameter) or non-respirable. Respirable particles can penetrate into the lower lung and can cause damage. Non-respirable particles are trapped in the upper respiratory system and can cause irritation. Regulatory standards require that respirable particulates be kept below 15 mg/m 3 and that respirable particulates be kept below 5 mg/m 3. All particulate measurements were well below the OSHA standards and the NAAQS was only exceeded (.166 mg/m 3 compared to the recommended level of below.15 mg/m 3 ) on one day Saturday, October 27, which was a very windy day. The building was not occupied by DOL employees on that day. In summary, we found that during the construction period from October 23-November 19, 212, measurements of mold spores, temperature, carbon dioxide, and particulates in the third floor elevator lobby of the DOL Building were all well within the standard acceptable range for indoor air quality. Relative humidity was somewhat low during this same time interval, and could be improved by upgrading the heating, ventilating, and air conditioning (HVAC) system. Our understanding is that equipment has been ordered to perform this upgrade and installation is scheduled for this winter. Please feel free to call with any questions. Regards, Sigrid Dahlberg, P.E. Environmental Engineer Carson Dorn, Inc. Enclosure Tel: Fax:

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9 1) Summary of Work: DOL Building Renovation Work Plan 212 Workers shall remove and replace interior finishes (including vinyl cove base, carpet, drywall, ceiling tiles, vapor barrier) and abate moisture or mold impacted insulation, studs, and plywood sheathing from each area in the Department of Labor Building, following the attached phasing diagram. These materials shall be removed substantially intact and shall be disposed of as nonregulated waste. 2) Site Preparation: A wood framed enclosure shall be erected to create a barrier around the remediation area. The HVAC supply and return air vents shall be blocked within remediation area. The area shall be ventilated with HEPA-filtered fans exhausted to the outside during wallboard demolition, maintaining a minimum flow rate of 4 air exchanges per hour. 3) Demarcation: The outside of the remediation area shall be demarked to establish a regulated area. Only workers with proper PPE for each work phase shall be allowed within the regulated area. 4) Material Removal Vinyl Cove Base, Carpet, Drywall, Insulation, and Vapor Barrier: The project will include removal and disposal of the following materials: carpet, drywall, ceiling tiles, insulation, vapor barrier, and ceiling tiles (see Section 6). All materials shall be loaded out through a chute directly from the work area to a dumpster. No materials shall be loaded out through the occupied spaces of the building. 5) Inspection/Removal/Cleaning Insulation and Studs: The project will include visual inspection, cleaning, and/or removal and disposal of the following materials: insulation, studs, and plywood sheathing. Upon completion of material removal, representatives of Carson Dorn, Inc., State of Alaska, and Alborn Construction will inspect the project to identify areas requiring cleaning, and/or replacement of structural members. The following guidelines will be used in determining course of action: a) Studs Where portions of studs are removed (for whatever reason) the remaining structure shall be reinforced as necessary for structural integrity. If conditions indicate current or recent water intrusion, the source of the leak shall be located and repaired. i) Wet, Damp, or Water Stained and Mold Growth: Wet, damp, or water stained portions of studs with mold growth shall be removed for disposal. Renovation Work Plan 1 Carson Dorn, Inc. Department of Labor Building November 212

10 ii) Rot: Portions of studs with rot shall be removed for disposal. iii) Wet No Mold Growth: Wet portions of studs with no mold growth shall be wet vacuumed, air dried, and left in place. iv) Damp No Mold Growth: Damp portions of studs with no mold growth shall be high-efficiency particulate air (HEPA) vacuumed, air dried, and left in place. v) Water Stained No Mold Growth: Water stained portions of studs with no mold growth shall be HEPA vacuumed, washed with detergent, dried, and left in place. vi) Mold Growth: Portions of studs with activemold growth shall be removed for disposal. b) Plywood Sheathing If conditions indicate current or recent water intrusion, the source of the leak shall be located and repaired. i) Wet, Damp, or Water Stained and Mold Growth: Wet, damp, or water stained portions of plywood sheathing with mold growth shall be HEPA vacuumed, cleaned with detergent, air dried, and left in place. ii) Rot: Portions of plywood sheathing with rot shall be left in place and reinforced as necessary for structural integrity. iii) Wet No Mold Growth: Wet portions of plywood sheathing with no mold growth shall be wet vacuumed, air dried, and left in place. iv) Damp No Mold Growth: Damp portions of plywood sheathing with no mold growth shall be high-efficiency particulate air (HEPA) vacuumed, air dried, and left in place. v) Water Stained No Mold Growth: Water stained portions of plywood sheathing with no mold growth shall be HEPA vacuumed, cleaned with detergent, and left in place. 6) Material Removal Ceiling Tiles: The project will include removal and disposal of the ceiling tiles. The air plenum above ceiling shall be sealed along framed containment wall after ceiling tiles have been removed. Renovation Work Plan 2 Carson Dorn, Inc. Department of Labor Building November 212

11 7) Cleanup: After abatement work is complete, final cleanup should include HEPA vacuuming of all materials and surfaces left in place. 8) Inspection: Upon completion of inspection, removal, and cleaning, representatives of Carson Dorn, Inc., State of Alaska, and Alborn Construction will again inspect the project to determine completeness of abatement work. Representatives will take moisture reading of studs using a portable moisture meter. The inspection will include photo documentation of the abatement work. 9) Build-Back: a) Encapsulate Ceiling and Studs: A spray encapsulant shall be applied to ceiling and to the interior surface of studs and plywood sheathing in all areas of the building. b) Install Insulation, vapor barrier, dry wall, paint, ceiling tiles, carpet, and vinyl cove base: Materials shall be installed as per specifications approved under separate work plan. c) Cleanup: After build-back work is complete, final cleanup should include HEPA vacuuming of all materials and surfaces. d) Enclosure Removal: Upon approval of final results of air sampling (see Section 11), the enclosure shall be removed to ready the workspace for reoccupation. 1) Worker Protection: If heavy mold growth is encountered, workers shall wear, at a minimum, the following PPE to be protected from potential exposure to mold: disposable coveralls, disposable gloves, eye protection, and half-face respirators equipped with HEPA filter cartridges. Other PPE that may be required for general jobsite safety will not be covered in this work plan. Used disposable PPE shall be disposed of in a sealed bag while in the decontamination chamber. Respirators should be worn until workers are outside the decontamination chamber. Respirators shall be cleaned and inspected daily. *Please note that all individuals using half-face respirators, must be trained, must have medical clearance, and must be fit-tested by a trained professional. In addition, the use of respirators must follow a complete respiratory protection program as specified by the Occupational Safety and Health Administration (OSHA). Renovation Work Plan 3 Carson Dorn, Inc. Department of Labor Building November 212

12 11) Air Monitoring: a) During-Project: 24-hour real-time sampling for relative humidity, temperature, carbon dioxide, and particulates in air will be conducted outside the work area for the duration of the project. Mold samples will be collected outside the work area once daily during the wallboard demolition portion of each phase and sent to ALS laboratories for analysis. b) Post-Project: 24-hour real-time sampling for relative humidity, temperature, carbon dioxide, and particulates in air will be conducted in the work area for a period of 1-day at completion of the work. Mold and VOC samples will be collected once during the day at completion of the work and sent to ALS laboratories for analysis after build-back and before reoccupancy in each phase. Renovation Work Plan 4 Carson Dorn, Inc. Department of Labor Building November 212

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