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HomeMy WebLinkAbout2014-09-10 PACKET 05.1. TO: Environmental Commission FROM: Jennifer Levitt, Community Development Director/City Engineer DATE: September 5, 2014 RE: Air Monitoring Background/Discussion The City of Cottage Grove, with cooperation and cost participation from 3M Cottage Grove, contracted for air monitoring to be performed on the 3M site from October 2010 through September 2011. This first year of sampling provided a base line for air moni- toring data prior to 3M accepting outside waste from non-3M generated sources. Air monitoring resumed in June 2013 when non-3M wastes to the incinerator had begun to be burned on a consistent and regular basis. Data was then collected from June 2013 to June 2014. The enclosed memo from Tom Henning with SEH outlines the results of the second year air monitoring and provides a comparison with the base line air monitoring data. Mr. Henning will present the findings at the Environmental Commission meeting and be available to answer any questions you may have regarding the sampling process or results. Recommendations It is recommended to not perform a third year of air monitoring testing for the site due to the fact that air monitoring results demonstrate compliance with the Minnesota health benchmarks. TECHNICAL MEMORANDUM TO:Jennifer Levitt, PE, City of Cottage Grove FROM:Tom Henning, PE, CHMM DATE:September 3, 2014 RE:Cottage Grove Ambient Monitoring -Second Year Results SEH No. 113702 1.0Introduction ® The City of Cottage Grove retained Short Elliott HendricksonInc. (SEH) to conduct ambient air monitoring at a location near the 3M Cottage Grove (“3M”) facility.The purpose of the monitoring is to measure concentrations of particulate matter, select metals, and volatile organic compounds (VOC) near the incinerator operated at the 3M facility.In 2009, 3M applied for an amendment to their air permit which would allow the facility to process non-3M generated wastes in the incinerator; the amended permit was issued in 2012.SEH conducted one year of monitoring, from October 2010 through September 2011, to determine ambient air conditions prior to 3M processing non-3M generated wastes.After 3M had begun processing non-3M wastes in the incinerator, SEH conducteda second year of air monitoring between June 2013 and June 2014 to measure ambient concentrations after this change. 2.0Monitor Location Selection The location of the air monitoring site, as well as the sampling and analytical methods used, were the same for the second year of monitoring as they were for the first year of monitoring.SEH staff worked with 3M staff, representatives of the Minnesota Pollution Control Agency (MPCA) and the City of Cottage Grove to selecta location for the monitoring.The selected site is located northwest of the incinerator stack on 3M property (inside the facility fence). The selected site met each of the following site selection criteria: 1.Located on 3M property so access and security are provided 2.Power is accessible to the site 3.Provides acceptable distances from sources of background emissions (i.e. highways, industrial facilities, etc.) 4.Location is in line with prevailing wind direction from the incinerator stack 5.The distance from the incinerator stack to the sampling location is approximately equal to the distance from the incinerator stack to the nearest residence. 3.0Methods The sampling and analytical methods used where selected to match ambient monitoring methods used by the MPCA at monitoring stations throughout the Twin Cities metropolitan area. This methodology was used so that the results of the monitoring near the 3M facility can be compared to the MPCA’s Twin Cities and metropolitan area and statewide monitoring data. Engineers | Architects | Planners | Scientists Short Elliott Hendrickson Inc., 809 North 8th Street, Suite 205, Sheboygan, WI 53081-4032 SEH is 100% employee-owned|sehinc.com|920.452.6603|888.908.8166 fax Cottage Grove Ambient Monitoring -Second Year Results September 3, 2014 Page 2 th day so that samples werecollected on the same days as In general, samples werecollected every 12 MPCA monitoring.The twelve day sampling cycle ensures that over the course of the sampling program, thth or 18 samples will be collected on each day of the week.Periodically, SEH collecteda sample on the 6 day to randomize the sample days. A high volume sampler wasused to collect 24-hour total suspended particulate (TSP) samples.The sampler turnedon at midnight of the sampling day and directedambient air across a filter for24 hours. The filter was analyzed for TSPandtwelvemetals.At the same time, a summa canister with a regulator was used to collect a 24-hour sample that was thenanalyzed for individual VOCs. Filters used with the high volume sampler were prepared andprocessed according to the U.S. Environmental Protection Agency (USEPA) Compendium Method IO-3.1 (USEPA, 1999) as applicable for gravimetric determination. This method describes the numbering, pre-field tare weighing of filters, and post-field final weighing of filters. Pre-field filters are conditioned in a room of constant humidity and temperature and are gravimetrically tarred. After air samples hadbeen collected, the filters were returned to the laboratory and conditioned as before and weighed. Filterhandling procedures found in Appendix B, G, and J of 40 CFR Part 50 were also followed. VOCs were collected and analyzed using EPA method TO-15 procedures. Six-liter summa canisters sanitized and placed under vacuum at or greater to 25 inches mercury were used to collect the VOC samples.Table 1 shows the monitoring program’s analytical methods, sampling equipment, target metals and individual VOCs. 8EFPI1IXLSHWERH)UYMTQIRX CompoundTest MethodSampling Equipment Total ParticulatesEPA Method IO-3.1Tisch TE-5170V EPA Method IO-3.4/ 1 MetalsTisch TE-5170V 3.5 Volatile Organic Summa Canister with a Tisch EPA Method TO-15 2 CompoundsTE-123flow controller Notes: 1 Individual metals monitored included: AntimonyCadmiumCopperManganese ArsenicChromiumIronNickel BerylliumCobaltLeadSelenium 2 Individual VOCs are listed on Tables 3 and 4. Similar to the first year, Pace Analytical of Minneapolis, Minnesotaperformedthe VOC analysis for the second year.However, Pacesubcontracted the metals and particulate matter analyses to Bureau Veritas of Novi, Michigan for the second year of monitoring.Bureau Veritasattained detection limits for the metals analysis at or below the detection limits attained by Pace in the first year of monitoring. During both years of air monitoring, SEHfolloweda quality assurance and quality control (QA/QC) program to help ensure monitoring results wereaccurate and precise.QA/QC procedures included collecting field and method blanks,calibrating field equipment,and periodically splitting sample analyses with the Minnesota Pollution Control Agency (MPCA).These steps provided a check that contaminants werenot introduced during the sample collection, handling,or analytical procedures. Cottage Grove Ambient Monitoring -Second Year Results September 3, 2014 Page 3 4.0Weather Conditions Weather conditions for each sampling datein monitoring year two, including wind speed and direction, temperature, and precipitation, are presented in Table 2.SEH used meteorological data collected at the meteorological station located at the 3M Cottage Grove facility and the Minneapolis-St. Paul airport to populate Table 2. 8EFPI;IEXLIV(EXEJSV1'SXXEKI+VSZI1SRMXSVMRK7XEXMSR Wind DirectionAverage WindRange WindAverage TempPrecipitation AB DatefromSpeed, mphSpeed, mphdegrees FInches 6/15/2013SE4.80.1 to 31.068.50.02 6/27/2013NW7.70.1 to 32.276.70.00 7/9/2013W8.80.7 to 41.976.90.34 7/27/2013NW9.10.3 to 30.755.30.02 8/2/2013N5.30.2 to 20.667.10.00 8/14/2013W3.40.3 to 13.463.50.00 8/26/2013S6.40.4 to40.085.70.00 9/13/2013NE3.60.3 to 12.556.60.00 10/1/2013W8.40.2 to 27.865.80.00 10/7/2013NW4.20.2 to 18.651.70.00 10/13/2013NW3.20.2 to 18.746.70.00 10/19/2013W5.10.5 to 29.839.90.06 10/31/2013W7.90.1 to 21.343.6Trace 11/18/2013NW11.80.5 to 38.029.40.00 11/24/2013S10.60.5 to 31.818.50.00 12/6/2013W7.31.6 to 25.9-1.80.00 12/18/2013SE6.70.3 to 33.922.30.00 Trace 1/5/2014NW12.01.7 to 35.8-8.9 Trace 1/17/2014NW8.81.5 to 43.76.8 1/29/2014S7.21.2 to 40.211.10.00 2/10/2014W4.60.9 to 37.1-4.50.00 2/28/2014SE7.80.7 to 37.43.20.04 3/6/2014SE10.73.3 to 31.120.10.00 3/18/2014E8.62 to 21.931.90.15 3/30/2014SE10.53.8 to 24.646.10.00 Trace 4/11/2014NE4.90 to 18.249.7 Trace 4/17/2014NW9.60 to 26.734.4 4/23/2014SE9.40 to 21.942.70.26 5/5/2014E6.10 to 14.355.40.00 5/17/2014W5.60 to 24.953.10.00 5/29/2014SE4.70 to 12.969.40.00 6/16/2014S8.70 to 41.271.00.38 A Wind direction based on average readings at the 3M Weather Station for each day of monitoring. B Source: National Weather Service Weather Forecast Office, Daily Weather Observations for the Twin Cities, MN (http://www.crh.noaa.gov/mpx/Climate/MSPClimate.php) Cottage Grove Ambient Monitoring -Second Year Results September 3, 2014 Page 4 5.0Incinerator Operations Someof the solventscombusted in the 3M incinerator are generated by outside sources. Figure 1 shows the amountof non-3M-generated solvents and3M-generated solventson a monthly basis from June 2013 –June 2014. During the second year of samplingwhen the incinerator was operating,the amount of non-3M generated solvent ranged from 11% to 58% of the total solvent incinerated and averaged 24%. The incinerator was down for much of the month of September2013 and all of May 2014. 6.0Results and Discussion Themaximum, minimum,andaverage concentrations measured during the second year of monitoring (2013–2014)are shown on Table 3. Also shown on the table arethe health benchmarksfor each compound and the maximum, minimum, and average concentrations measured during the first year of monitoring (2010 –2011). 6.1Compounds Not Detected A total of 53VOCs and 12 metals weremonitored throughout the year. Ninemetals and sixorganic compounds have been consistently detected at the 3M monitoring station(i.e., the compounds were detected in over half of the sampling events): antimony,cadmium, chromium, copper, iron, lead, manganese, nickel,selenium, 2-propanol, benzene, dichlorodifluoromethane (Freon 12), methyl chloride, methyl ethyl ketone, and toluene. Particulate matter was also detected in each sample. Of this total, 27 VOCs (i.e.,about half of the total) were not detected in any of the samples. In addition, sevenadditional compounds were only detected in one of thesampling events.The compounds not detected during the second year of testing are shown on Table 4. 8EFPI'SQTSYRHW2SX(IXIGXIHMR7EQTPIW Dichlorobenzene (m) 1,1,2,3,4,4-Hexachloro-1,3-butadiene 1,1,2-TrichloroethaneDichlorobenzene (o) 1,1-DichloroethaneDichlorotetrafluoroethane (Freon 114) 1,1-DichloroetheneEthylene Dichloride 1,2,4-TrichlorobenzeneEthylene Dibromide 1,2-DichloropropaneMethyl Bromide 1,3-ButadieneMethyl Tert-Butyl Ether Benzyl ChlorideStyrene BromodichloromethaneTrans-1,2-Dichloroethene ChlorobenzeneTrans-1,3-Dichloropropene ChloroformTribromomethane cis-1,2-DichloroetheneTrichlorofluoromethane(Freon 113) cis-1,3-DichloropropeneVinyl Chloride Dibromochloromethane 6.2Comparison with Health Benchmarks and Ambient Standards The monitoring shows that, for the compounds monitored, the air quality in Cottage Grove during the 2013to 2014 ambient monitoring program meets Minnesota health benchmarks.Table 3shows the average monitored concentrationsfor each compound and theassociated health benchmark. 3 On one date,August 2, 2013, an arsenic concentration of 0.0031µg/mwas detected, which is slightly 3 above the health benchmark of 0.00233µg/m.On the same day, the measured benzene concentration 33 was 1.7 µg/m, which is greater than the health benchmark for benzene, 1.28µg/m.However, the health benchmarksfor arsenic and benzene representan annual average exposure concentration (chronic exposure), not a daily average concentration. Theannual average concentration for arsenic and benzene were below their respective health benchmarks when compared to the prescribed period of exposure time.Also note that on August 2, 2013, the wind direction was primarily from the north (see Table 2). Cottage Grove Ambient Monitoring -Second Year Results September 3, 2014 Page 5 Since the 3M Cottage Grove facility is located south and southeast of the monitoring location, the 3M plant is an unlikely source of the measuredconcentrationson that day. 6.3Comparison with First YearMonitoring Results The secondyear’s ambient monitoringresults weregenerally comparable with results from year one of monitoring(Table 3). TSP concentrations were about 32% lower during the second year of monitoring. Antimony, copper, and lead concentrations were higher during the second year while average concentrations of the other metals were lower during the second monitoring year. Most of the VOCs detected during the second year of monitoring were infrequently detected. That is, many of the sample results showed the concentration of these compounds were less than the detection limit of the analytical method. Twenty six VOCs haveat least one detectable concentration during the second year of monitoring. Of these twenty six compounds, nine had average concentrations that were higher than the first year monitoring results and seventeen compounds had lower average concentrations. Of the six VOCs which were detected consistently during year two of monitoring, twocompounds had lower average concentrations during year two, while fourhadhigheraverage concentrations(Table 5). 8EFPI%ZIVEKI'LERKIMR'SRGIRXVEXMSRJVSQ=IEVXS=IEV7IPIGX:3'W VOCChange from Year 1 to Year 2 Benzene7% decrease Freon 1217% decrease Freon 1122% increase Methyl Chloride43% increase 2-Propanol68% increase Toluene17% increase Attachments: . Table 3Summary of Second Year Air Quality Monitoring (2013 –2014) for Detected Compounds Figure 1. Non-3M Generated Solvent Compared to Total Solvent Incinerated KHB/tah \\sp3020-1\projects\ae\c\cottg\113702\memorandum\seh memo_year two monitoring results_2014.09.03.docx