November 11, 2011 Mr. Tim Squier 487 Deerfield Dakota Dunes, SD 57049 Re: Project #: 4004-040 487 Deerfield, Dakota Dunes SD Microbial Clearance Testing INTRODUCTION: This report presents the findings of a post remediation clearance assessment following microbial remediation activities conducted at 487 Deerfield, Dakota Dunes SD. The remediation work was performed by Legacy Environmental, Inc.. The assessment included visual inspections of the work areas as well as the collection, analysis and interpretation of microbial surface and air samples. The investigation was performed on October 17, 2011 by Dave Gutterud. The scope of our sampling activities was limited to the collection of surface and air samples from work areas throughout the basement. Surface sampling was completed using a Hygiena SystemSURE Plus ATP Hygiene Monitoring System and Hygiena PRO-Clean 100 swabs. Analysis of the surface samples was performed onsite. Air sampling was performed using non-viable sampling methods. Indoor Environment Group provided no remediation design, management or oversight services nor were we hired to determine if the building or the work areas were mold free. METHODOLOGY: At the conclusion of the remediation project, personnel from the (IE Group) conducted a visual inspection of the basement. During the visual inspection we look for signs of remaining microbial growth, conditions that may contribute to future microbial growth, evidence of satisfactory disinfection work, general cleanliness of the work areas and for confirmation that the scope of work has been completed as per agreement with the client. Surfaces are also tested for moisture content. Upon completion of the visual inspection, preliminary clearance testing is performed. For this project surface swab sampling methods were employed. Air sampling is performed upon successful completion of the surface sampling activities. Surface Samples SystemSure swabs - Bioluminescence Surface swab samples were collected from numerous surfaces throughout the space to assess the levels of microbial/organic materials present. At each of these locations a 2 x 2 area was sampled using a (651) 779 4300 (651) 344 5980 fax
Client: Tim Squier Page: 2 of 6 Hygiena Ultrasnap ATP swab. After collection, the swabs prepared according manufacturer specifications and loaded into the SystemSure Plus ATP Hygiene Monitor and the results recorded onsite. The Hygiena SystemSure Plus Hygiene Monitoring systems utilizes a luminometer to measure the level of ATP (adenosine tri-phosphate) bioluminescence present within the swab sampler. ATP is present in all living organic material including mold. Accordingly, microorganisms are detected by the technique but also detected are other organic residue such as bacteria, yeasts, bio-film, somatic cells, etc. The results are presented in RLU (relative light units) which do not necessarily correlate to conventional CFU measurements but rather indicate the cleanliness of the surface and the potential for pathogens, unhygienic surfaces or active microbial growth. Surface Samples Pro-Clean swabs - Protein Surface swab samples were collected from numerous surfaces throughout the work areas to assess the protein levels at each location. At each of these locations a 4 x 4 area was sampled using a Hygiena PRO-Clean 100 swab. After collection, the swabs prepared according manufacturer specifications and the results recorded onsite. PRO-Clean swabs detect protein residues present on surfaces. Proteins are present in mold spores and in deposits left behind by dying mold spores. The swabs employ a colorimetric system to indicate the presence of protein on the surface sampled. The color change provides a semi-quantitative measure of the surface cleanliness. The more contamination present, the quicker the color change to purple and the darker the color. While the identification of proteins does not specifically signify that mold is present, positive results along with visual evidence or other test results can help to confirm or disprove the presence of mold spores. Surface Sample Methodology Elevated ATP and protein levels do not, on their own, specifically signify the presence of mold on surfaces tested. However, microbial organisms are one of the few substances that do contain ATP and protein. Therefore a positive result from both testing methods usual indicates a high probability of mold growth or contamination. Moisture Testing Moisture levels were checked using a Delmhorst BD-10 Contractor s Moisture Meter. The BD-10 uses pin type contacts which measure electrical resistance between the pins when inserted into the products to be tested. Microbial Air Samples AllergencoD Air samples were collected using AllergencoD air sampling cassettes. AllergencoD cassettes are specially designed to trap a wide range of airborne aerosols including mold spores, pollen, insect parts, skin cell fragments, fibers and other particulates. The cassette collects both viable and non-viable sample specimens. This method employs an external air pump to pull ambient air into the air sampling cassette where particulate matter is impacted onto a sticky glass slide contained within the housing of the cassette. The pump is calibrated to 15 LPM prior to sample collection. The samples are normally run for 10 minutes. After collection, the cassettes are submitted to the laboratory for microscopic analysis. Air samples were collected in the following areas: Basement, Main Floor - Living Room. A third sample was collected outside for comparison purposes.
Client: Tim Squier Page: 3 of 6 RESULTS: The results of the analysis of the surface swab and air samples collected during the investigation were as follows: TABLE 1 POST-ABATEMENT SURFACE SAMPLES Swab # 01 02 03 04 05 06 07 08 09 Location Basement Stairway Bottom plate Basement Stairway Stud Basement SE Corner Basement North wall Basement North wall Door frame Basement Small Garage Garage door Basement Small Garage Basement Small Garage Basement Bathroom Bottom plate ATP Swabs Protein Swabs Mold Presence Likelihood + Result * Comment Result ** Comment 13 RLU Acceptable - - - 0 RLU Acceptable - - - 16 RLU Acceptable - - - 9 RLU Acceptable - - - 18 RLU Acceptable - - - 58 RLU Elevated Green Pass - 22 RLU Acceptable - - - 41 RLU Caution Green Pass - 6 RLU Acceptable - - - * RLU Relative light units Below 25 RLU Acceptable 25 RLU to 50 RLU - Caution Over 50 RLU - Elevated ** Protein swab color indicators Green pass, no protein detected Gray caution, low protein level Purple fail, protein detected + Mold presence summary High high ATP and high protein Moderate ATP and high protein Low low ATP and low protein - Unlikely no ATP and/or no protein
Client: Tim Squier Page: 4 of 6 TABLE 2 POST-ABATEMENT AIR SAMPLES Sample # Location Sample Type Results Fungal Type SQ11 SQ12 OUT02 Basement Main Floor - Living Room Outside Allergenco Air Sample (150 liters) Allergenco Air Sample (150 liters) Allergenco Air Sample (150 liters) 7 Alternaria sp 127 spores/m 3 67 Ascospores 13 Aspergillus/Penicillium types 40 Cladosporium sp 20 Alternaria sp 113 Ascospores 253 spores/m 3 33 Aspergillus/Penicillium types 13 Basidiospores 73 Cladosporium sp 253 Alternaria sp 1973 Ascospores 520 Aspergillus/Penicillium types 6147 spores/m 3 947 Basidiospores 2360 Cladosporium sp 73 Smuts/Periconia/Myxomycetes 20 Pithomyces sp = species Includes all species for this genus of fungal colony isolated (not identified to a specific species). DISCUSSION: This clearance testing was performed following microbial remediation and reconstruction work by Legacy Environmental, Inc. in response to water damage and possible mold growth in the basement. During our visual inspection we found no evidence of any microbial growth on the surfaces we examined. It did appear that all surfaces had been adequately cleaned and treated to remove any previous growth and to inhibit future growth. Surfaces throughout the basement were tested for moisture content and all materials were found to be dry. Swab surface samples were collected from nine locations. We selected areas on a worst case basis. Microbial Surface Sampling Indoor Environment collected 9 Hygiena Ultrasnap ATP swab samples and 2 PRO-Clean 100 swabs to evaluate the post abatement surface concentrations of microbial/organic matter in the building. All swabs are analyzed on site and evaluated according our post-remediation clearance criteria. While no government standards currently exist regarding acceptable post remediation ATP bioluminescence levels, a number of texts suggest that surfaces found to contain ATP bioluminescence levels below 50 RLU are considered clean and in ideal hygienic condition. However, Indoor Environment Group uses a clearance criterion of 25 RLU for post remediation surface sampling. Surfaces found to have ATP levels above 25 RLU are also sampled using a PRO-Clean protein swab. Elevated ATP and protein levels do not, on their own, specifically signify the presence of mold on surfaces tested. However, microbial organisms are one of the few substances that do contain high ATP
Client: Tim Squier Page: 5 of 6 levels AND high protein levels. Therefore positive results from both testing methods usually indicate a high probability of mold growth or contamination. Conversely, the absence on one usually indicates a low probability of mold contamination. In this case, swabs samples collected in two locations identified elevated ATP levels although protein swabs collected in the same locations were negative. Accordingly, we do not believe that an elevated level of mold is present at any sample location. Considering the environmental conditions present at the time of testing, the analysis of the surface samples collected at the conclusion of the abatement project found microbial surface levels within the work areas were within the normal range for a facility of this type. Allergenco Air Sampling Indoor Environment collected two Allergenco bioaerosol samples to evaluate the post abatement airborne concentrations of microbial/particulate matter in the building. Laboratory analysis of the bioaerosol sample collected from the Basement found a total spore count of 127 spores/m 3 and the bioaerosol sample collected in the Main Floor - Living Room had a total spore count of 253 spores/m 3. The outside sample collected for comparison purposes measured 6147 spores/m 3. While no government standards currently exist regarding acceptable indoor bioaerosol levels, comparisons of the types and quantities of fungi and other particulate matter present in the indoor air can provide insight into the status of the facility s air quality. Interpreting the results involves three primary steps. First, an effective interpretation is based on the comparison of indoor and outdoor samples. Under ideal conditions, the indoor air fungal spore count should be lower than the outdoor level and should exhibit a similar distribution of fungal types. The presence of an elevated indoor level or significant differences in population types can signal a potential indoor air quality problem. Various circumstances can however affect this relationship. In buildings that rely on open windows for ventilation the indoor population of fungi can be expected to more closely resemble the outdoor population. Recent rainfall, snow or other climatic change can alter the outdoor populations significantly. Human interferences such as lawn mowing or leaf raking can also raise outdoor levels. The second step in interpreting sample results involves the comparison of spore counts and species distributions to levels considered normal for facilities of the same type and the same time of year. Included in this step, we always look for the presence of indicator molds. These include some Aspergillus species, some Penicillium species, Acremonium spp., Sporobolomyces spp., Stachybotrys chartarum, Memnoniella echinata, Tritirachium oryzae, Ulocladium botrytis, U. chartarum, Cladosporium spp., and Chaetomium spp. The presence of these species is often linked to an indoor growth source especially if their concentrations are dissimilar to those detected outdoors. Finally, the third step when interpreting results involves the categorization of mold detected using a system that groups mold into one of 3 hazard classes based on associated health risk. Hazard Class A includes fungi or their metabolic products that are highly hazardous to health. These fungi or metabolites should not be present in occupied dwellings. Presence of these fungi in occupied building requires immediate attention. Hazard Class B includes those fungi which may cause allergic reactions to occupants if present indoors over a long period. All other fungi are grouped into Class C and are fungi not known to be a hazard to health.
Client: Tim Squier Page: 6 of 6 Indoor Environment Group found that the indoor samples collected in this case met the following criteria: 1. The total indoor spore counts were lower than the outdoor sample. 2. The distribution of species on the inside samples was similar to the outdoor sample. 3. No unusual species or indicator molds were identified on the indoor samples. 4. No fungi in either Hazard Class A or B were identified in the indoor samples. Accordingly, we do not consider the indoor levels to be elevated and do not feel that they indicate the presence of an indoor microbial growth source. Additional information regarding our process for evaluating the airborne microbial levels is available upon request. FINDINGS: Based on the results of our visual inspection in each work area and the results of the surface and air sampling conducted at the completion of this work, believes that the remediation project has been successfully completed in the target areas and the environmental conditions within the space have returned to a normal condition. No additional cleaning or testing will be necessary unless additional mold growth occurs prior to reinstallation of building materials. REMARKS: The environmental services provided by Indoor Environment Group's industrial hygienists, technicians, analysts and project managers for this project have been conducted in a manner consistent with the degree of care and technical skill exercised by environmental professionals currently practicing in this area under similar budget and time constraints. Recommendations contained in this report represent our professional judgment at the time the project was performed. This concludes our report. Any questions regarding the fieldwork, sample results or presented findings should be directed to Dave Gutterud