3.4. SR 08-25-1997City of
iver
MEMORANDUM
** Item# 3.4.**
TO:
FROM:
DATE:
SUBJECT:
Mayor & City Council
Cliff Skogstad, Building Official
July 28, 1997
Rooftop Rental Space for MPCA Air
Sampling Equipment
On June 20, 1997, Mr. Don Bach from Metropolitan Pollution Control Agency
(MPCA) contacted me regarding a possible rooftop site for their equipment.
This equipment is used for monitoring toxic air pollutants. I showed Mr.
Bach our roof area and he was very interested in using the northeast corner
of the roof for installing two rooftop units. Attached for your review is
information Mr. Bach provided to address any concerns you may have. As is
indicated in this information, these monitors are located in many different
areas of Minnesota.
If the City Council approves, this monitor would be installed on our roof for
approximately one year. All fees incurred from the installation of these
monitors (i.e., electrical hook-up, pavers going to the equipment for the
protection of the roof membrane) will be paid by MPCA. In addition, MPCA
will reimburse the city for the electricity used for this equipment. The data
provided from this equipment will be collected weekly by MPCA staff.
Action Requested
Staff is requesting approval to allow MPCA to rent roof space for their
equipment to sample air quality.
\\elkriver\sys\shrdocXcouncil\mpcaraon.doc
13065 Orono Parkway · P.O. Box 490 · Elk River, MN 55330 · TDD & Phone: (612) 441-7420 · Fax: (612) 441-7425
Typical Toxics Monitoring Site PMlO/Metals Monitor
Xontech VOC / Carbonyl Monitor
PROJECT DESCRIPTION
OBJECTIVES
The MPCA's Statewide Air Toxics Monitoring Study which will be conducted in commulaities
throughout Minnesota has four major objectives. The objectiveS are to:
1. Characterize ambient air concentrations and deposition rateS of VOCs and particulate
metals in rural and urban/suburban atmospheres and their seasonal variation;
2. Compare concentrations ofspecifi¢'VOCs and particulate metals at nnal and
urban/suburban siteS with:
a. other rural and urban/suburban areas in a similar part of the state; and'
b. other rural and m'bau/suburban areas in a different part of the state.
3. Provide a meam for prioritizing and planning future work and sampling in a more in-
depth and pollutant-specific and/or source specific basis in local areas.
4. Provide data for a preliminary screening assessment of potential health and
environmental risks fi'om exposure to selected VOCs and particulate metals.
STUDY RESULTS EXPECTED
Many toxic air pollutants, which are emitted by a variety of point, area, and mobile sources, are
present in the atmosphere at part-per-billion levels or below. A common assumption is that
exposure, to these toxic air pollutants in general is lower in small towns and rural areas than it is
in larger cities and metropolitan areas. The Statewide Air Toxics Monitoring Study will collect
baseline data for ambient air concentrations of VOCs and particulate metal_~ that people are being
exposed to in various locations in the state and provide a means of testing this general
assumption. The MPCA cun'ently has ambient air' concentration data for specific VOCs in a few
locations in the Twin Cities MetropOlitan area. There is, however, a general lack of ambient air
data for most toxic air pollutants in the majority of rural and urbau/~uburban settings in
Minnesota. Data collected in th[q study will provide MPCA with baseline information in
particular communities.so that future changes in ambient air concentrations of specific toxic air
pollutants can be more readily 'identified.
An equal amount of sampling is planned to be conducted in all areas of the state. The Twin
CitieS Metropolitan area will be included in the study became of the large population that resideS
in the 7-county area (Anoka, Carver, Dakota, Hennepin, Scott, Ramsey, and Washignton
Counties). Including the Twin Cities Metropolitan area in the study will allow the M~CA.to
compare data collected in the largest metropolitan area in the state with data collected in less
populated areas. These comparisons will provide a benchmark for assessing exposure to toxic air
· pollutants in other Parts of the state. Realistic assessment and cost-effective management of the
health risks posed by toxic air pollutants in urban/surburban and rural air require acctn-ate
information about people's actual exposures. A statewide monitoring study will help to identi~
the most important chemicals in the ambient air and to more accurately estimate potential risks
from these chemicals. The state,vide monitoring data will also help to identify areas of concern
that'may wa_mant further monitoring activities.'
DETERlVHNiNG SCOPE OF PROJECT
HISTORY OF AIR TOXICS MONITORING IN ~SOTA
In the mid- to late 1980s there was a movement by a number of states to assess non-criteria
pollutants which arc otherwise known as toxic air pollutants. At the same time, the
Environmental Protection Agency ('EPA) began several programs to determine the concentrations
of toxic air pollutants in ambient air. One such program was the Special Urban Air Toxics
Monitoring Program. EPA invited state participation in this program by allowing the states tO
"buy" into the monitoring effort for approximately $20,000 per site per year. For that
expenditure, EPA provided sampling equipment' and laboratory analyses for selected volatile
organic compounds (VOCs) and carbonyl compounds:
After evaluating the costs of a multi-year monitoring program and determining that it was more
cost-effective to conduct the sample collection and analysis in-house, the MI~CA decided to
purchase its own sampling and labo.ratory analytical equipment. By upgrading its sampling and
laboratory analysis capabilities, ,the MPCA has been able to determine multi-year exposures to
V0Cs and earbonyl comp6unds in downtown Minneapolis, St. Paul, and Duluth.. Additional '
funding from industrial sources has complemented the MPCA's monitoring efforts.
additional funding has allowed the MPCA to determine exposure profiles for VOCs and carbonyl
compounds for the Pine Bend~. St. Paul Park, and Newport areas.
While exposure p~files for VOCs and carbonyl compounds have been determi-ed for selected
urban and industrial areas, due to limited dollar and staff resources these types of exposure
profiles do not exist for most of Greater Minnesota. To overcome these HmitatiOus, Legislative
initiatives were submitted for funding consideration over the last several years to expand the Pine
Bend Monitoring Network to other areas of the state. In I995, the Legislature approved a
$400,00 increase in the MPCA's Air Quality'Division operating budget (July 1,1995 through
June 30, 1997 ·
AIR TOXICS ISSUES ~ MPcA NEEDS TO CONSIDER
Over the last several years a number of questions and issues regarding air toxics in Minnesota
have been brought to MPCA staff's attention. These.questions and issues can be placed in three
broad categories: A) Inhalation and direct exposure to chemicals; B) Persistent and/Or
bioaccumulative pollutant effects on human health and the environment; and; C) Source
· contributions of toxic air pollutants to receptor sites. The following list presents some of these
questions and issues that have bc~n discussed owr the last scveraI years:
A. Inhalation and Direct Exposure to Chemicals
What are "background" concentrations of toxic air pollutants in the Twin Cities Metro
Area and other urban areas in Minnesota and do these concentrations pose a potential
risk to .the general public?
The MPCA has some ambient air concentration data for specific VOCs in a' few
locations in the Twin Cities Metro are~ However, there is a general lack of ambient air
data for most toxic air pollutants in the lliajoi'ity of rttral and urban settings in Minnesota.
A state'wide monitoimg effort would collect data to determine "background
concentrations" in other COmmtmlties itl other parts of the state.
2. Are people living in urban areas exposed to more toxic air pollution than people living ia
mml and small town areas?
In genei-al, one would expect that people living in mml and small town areas would have
less exposure to toxic air pollution. However, some available data suggests this
assumption may not be applicable in all cases. A review of the Toxic Release Inventory
data for I994 shows that relatively large sources of air toxics ern{ssions are located in
some smaller cornrntmities. A statewid~ toxics monitoring study should be able to
deterrn{ne if people in rural areas are beiug exposed to the same level of toxic a/r
pollutants as people living in urban and small town areas. In addition, a relative ranking
of pollutant levels at locations from throughout the sram will be possible (i.e., the
concentrations of toxic air pollutants found in various divergent cor~r~,,-{ties can be
compared). The question of which town or region of the state has the lowest ambient air
concentrations of toxic air pollutants may be answered (with{n the Hrn{ts of the study).
3. Of the chemicals that am found in ambient air, which have the greatest impact?
The MPCA published a report in 1991 entitled: "Priority ranking for pollution
prevention demonstration projects: A ranking of Minnesota industrial emitters of toxic
air pollutants" (MPCA 1991). A risk 5CI~en[n~ atlalysis was conducted in th[~ rgport arid
it identified chromium and arsenic as two important pollutants that may be impacting
human health. However, very l~rn~ted monitoring data are available to evaluam whether
the current concentrations of these metals in ambient air present a real or potential
problem to human health.
In addition to the priority ranking report, the MPCA published a report in 1992 entitled:
"Estimation and evaluation of cancer risks from air pollution ia the 1Vt~nneapol~St. Paul
metropolitan area" (MPCA 1992). This 'ha'ban soup study" identified the following
pollutants as potentially contributing the most to excess cancer incidence in the Twin
Cities area: diesel and gasoline particulate, wood stove particulate, 1,3-butadiene,
chromium (+6), polycyclic organic matter, formaldehyde, and benzene. The risk
estimates in this study were based only on dispersion model results. No ambient air
monitoring data were available at that time to compare to modeled concentrations.
In comparison to the MPCA's "urban soup study", a 5-city study conducted by the
Environmental Protection Agency identified polycyclic organic matter. (POM), 1,3-
butadiene, formaldehyde, chromium (+6), benzene, methylene chloride, and ethylene
oxide as pollutants contributing the most to excess cancer risk (EPA 1989). This study
used acma! ambient air monitoring data to estimate cancer risks. A statewide monitoring
study could help gather data in M]nn~om tO identify the most important chemicals in the
ambient air and to more accurately ~mate potential risks from these chemicals.
B. Persistent and/or Bioac~umulative Pollutant Effects on Human Health and the ~nvironment
1. What are the chemicals of concern in MinnesOta'S ellvironment?
To date, mercury has been identified as a chemical of concern in Minnesota's
environment (MPCA 1994a). In addition, PCBs and dioxins have received considerable
attention in the Minnesota Department of Health's fish consumption advisories that are
published yearly for selected lakes in the state. However, them is limited data for other
pollutants.
The EPA's Great Waters Program (1994) has identified the following as "chemicals of
concern" for the Great Lakes, Lake Champlain, Chesapeake Bay, and other "Crma
Cadmium and compounds
Chlordane
DDT/DDE ..
Dieldrin
Hexachlorobenzene
alpha-Hexachlorocyclohexane (alpha-HCH)
Lindane (lambda-Hexachlorocyclohexane)
Lead and compounds
Meamury and ¢omt>otmds
Polychlorinated biphenyks (PCBs)
Polycyclic or~nic ma_~er (POM)
2,3,7,8-Tetrachlorod~enzn furan (2,~,7,8-TCDF)
2,3,7,8-Tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD)
Toxaphene
Nitrogen compounds
The Lake Superior Binational Program (1995) has identified the following as "Lake
Superior critical pollutants":
Alpha-BHC Aluminum
Chlordane Arsenic
DDT/DDE Cadmium
Hepm:hlor epoxide Chromium
· Hexachlorobenzene Copper
Oc~hlorostyrene Iron
Polycyclic Aromatic Hydrocarbons Lead
PCBs Manganese
TCDD eq~uivalencs (dioxin or furans) Mercury
Toxaphene Nickel
Zinc
Both lists include semivolatile organi.'c compounds and metals. It is likely that pollutants
that are deposited from the atmosphere to the C-teat Lakes, and in particular to Lake
· Superior, will also be deposited to inland lakes and their surrounding terrestrial '
watersheds. One could then consider the Great Waters and Lake Superior Binational
Program'~pollutants of'conc~zn" to also be of concert in Minnesota. A comprehensive
monitoring effort would help identify the chemicals of concern in specific areas of the
state.
What are "background" concentrations of these ~chemicals of concern" in the
environment?
Background concentration data in Minnesota is primarily available for mercury in fish
and sediment, with some dam available for mercury concentrations in other parts of
aquatic ecosystems and soil (Moyle 1972; Helwig and Hcqskary 19T2; Swain and Helwig -
1989; Sorenson eL al. I990; Nater and Cn'igal 1992; Sw~irt et. al. 1992). Ther~ is limited
data for other metals in soil (Pierce et. al. 1982; MPCA 198o'). Additional sediment data
is being collected on a statewide basis through a Legislative Commi~ion on Minnesota
Resources (LCMR) Mercury Study being coordinaled by the MPCA. This LCM1R. study
builds upon previous sediment core data collected in northe~ Nflnnesota (Swain et. al.
1992). Other than the statewide data being collected in'the LCMK Mercury Study, most
data for metals is limited to specific areas and may not be readily applicable to other
areas of the state.
An'important piece of information that is often missing and is critical for determining
background concentzations is the deposition of the various pollutants to selected
locations in the state. Mercury in precipitation monitoring has been ongoing in the stae
since 2990 (Sorenson et. al. 1994). However, there is llmlt~l da~ on the concentration
of other metals in precipitationin Minnesota. A ~de monitoring study could
potentially provide information on pollutant deposition in vaxious parts of the state to
estimate background concentrations.
3. Are pesticides ofconcem in 1Minnesota'S environment?
Due to intensive agricultural prances, pesticide use in MinneSOta iS common. The ]isis
of ch'emicais of concern for the Great Waters and Lake Superior indicates that pesticide
contamination is occurring izi theSe large water bodies. The potential impacts of
pesticide contamination in smaller water bodies may need further attention in Minnesota
and other states. A pesticide component in the statewide toxics monitoring study would
provide information on the amounts of specific pesticides being deposited in various
locations in the state.
C. Source Contributions of Toxic Air Pollutants to Receptor Sites
I. What types of emission surees are the most important contributors to ambient air
concentrations of toxic air pollutants?-
Industry has argued that mo.bile sources contn'bute si~iflcantly, to ambient air
concentrations of toxic air pollutants. The MPCA's "urban soup study" (1992) is most
often cited as a reference for industry's cia/ms in this regaZ~. II1 addition, industry states
that k has been unfairly targeted for reductions ofto~ic air pollutant emi~ions whil~ thc
MPCA has ignored the'contributions of mobile sources.
Ambient air monitoring data, in conjunction with multivariate statistical analysis
techniques, can be used to identify important contributors of specific toxic air pollutants
at receptor sites. The 3M Cottage Grove Environmental Monitoring Study identified
si~iflcant contributions of PM~0 from secondary sulfate, combustion/transportation
sources, and crustal materials to receptor sites located at various distances from the
facility ('RUST 1994a). In turn, the 3M incinerator was estimated to only contn'bute a a
small amount of the particulate matter (ma~mum of 2.5%) for thc sampling days that
were analyzed for source contn'butions.
A statewide monitoring study can help collect data to identify the important contributors
of toxic air pollutants in other areas.
What are the most'important contributors to deposition of persistent and/or
bioaccumulative pollutants in Minnesota?
To date, there is considerable debate regarding the primary contributors of persiStent and
bioaccumulative pollutants to Minnesota's environment.. There is also considerable
discussion on the importance ofloeal source contibutions versus regional source
contributions versus national and/or global contributions.
No actual work has yet bden done in M{rmesota to identify the most important
contributors of such pollutants as mercury or dioxin to recePtor areas. Some WOrk is
progressing in the LCMR mercury study currently being conducted by the MPCA to
collect data that can eventually be used to determine important source contributions. In
addition, EPA is considering doing some "impacts analysis" by determining source
contributions of mercury and other Great Waters "chemicals of concern" to the Great
Lakes. However, the ability to do this source contribution es~mate is still several years
away. A statewide toxics monitoring, study could collect additional data to help identify
the important contributors of persistent and/or bioaccnmulative pollutants to important
surface waters.
A CONII~REI-IE1NSIVE STUDY TO ADDRESS AIR TOXICS ISSUES
A comprehensive a/r toxics study should i~¢Iude pollutants from the following thr~ major
categories: VOCs; semivolatile orgmic compounds; and metals. The semivolatile organic
compounds and metals of concern are genera, y considered to be persistent and/or
bfoaccumulative and include such compounds as PCBs, dioxins and turms, polycyclic aromatic
}{ydrocafoons (PAIqs), hexa= md pentm:blombenzene, chromi,~ m~m~c, and m~. la.
addition, a complete study would include collecting ,mMenl: air and dc'~s~on samples.
Deposition monitoring would I/kely include collecting and analyz/ng pr~cip~on (~t wet
deposition) samples, and collecting and analyzing sed~r~er~ core samples (M~toricaI 4,~ on
aeposiUon).
Collecting samples' for each pollutant category requires rl~fterent equipment and methodologies.
For example, V0C samples ~: tTpically collected in Summa canisters. Semivolatile organic
compounds ar: typically collected with PUl: samplers or Hi-Vol (high volume) samplers
containing some type off,in cartridge to prevent volatflimtion of the pollutants. Pm'ticulate
metals am typically collected by high volume samplers drawing air across a filter with the
particles then being capt~d by the tilt. er material.
',~ addition to the d{~'emnt collection methodologies for each pollutant camgory, different
.aboratnry analysis methods are also required. The Air Qualit7 Laboratory can conduct some off
these analyses (Method T0-14 for VOCs), however, analysis of samples for diox~--ifurans,
PAHs, and pesticides requires a r~latively complicamd extraction and analysis process that would
likely need to be contracted o~ to another laboratory. Pa.~dculam metals can be analyzed by
several methods that require the barticles tn he extracted fi'om the filt~r and put into'solution for
'analysis (Inductively Coupled Argon Plasma and GTaphit: Furnace Atomic Absorption). The
concentration ofmet~!s on a filter can also he det~,-~,~r,ed by such non-d~ve means as X-
ray Fluorescence or Neutron Activa/ion Analysis.
List of the re{nor civil divisions to be sampled in the M{nnesota Pollution Control
Agency's Statew~de Ak Toxics Monitoring Study.
SA_MP~ YEAR
MPCA REGION* I. 1996-1997 2. 1997-1998 3. 1998-1999 4. 1999-2000 5. 2000-2001
REGION 1 Wag~er Township; Hibbifig; Duluth; Virginia; Duluth;
DULLF~I-I Aittcin County St. Louis County . St. Louis County St. Louis Gounty St. Louis County
Crier 5) Crier 3) Crier 1) Crier 4) Crier 1)
REGION 2 Li~e Falls; Elk River; St~ Cloud; St. Michael; Fort Ripl~T,
~RAINERD Morrison County Sherbume County Steams County Wright County Crow W'mg County
[Crier 3) Crier 2) Crier 1) Crier 4) Crier 5)
REGION :3 Alexandria; Fergus Fails; Brandon Township; Perham; Moorhead;
DETROIT LAKES Douglas County Otter Tail County ~Douglas County Otter Tail County Clay County
Crier 3) Crier 2) Crier 5) Crier 4) Crier 1)
REGION 4 Pipestone; Granite Falls; Holloway;, Hutchinson; Willmar;
MARSHALL Pipestone County Yellow Medicine Swift County McLeod County Kandiyohi Count5,
County ..
Crier 3) Crier 4) Crier 5) Crier 2) (Tier 1)
REGION $ ' Leon Township; Rochester, Winona; Albert Lea; Nlorth Mankato;
ROCHESTER Gooclhue County Olrnsted County Winona County Freeborn County Nicollet County
Crier 5) :crier 1) Crier 2) Crier 3) Crier 4)
REGION 6 .Plymouth; Minneapolis; West Lakeland St. Paul; Apple Valley;
TWIN CITIES Hennepin, County Hennepin County Township; Ramsey County Dakota County
i Washin~on County
[Crier 3) Crier 1) [Crier 5) i (Tier 2) Crier 4)
ADDITIONAL International Fails; Warroad; Bemidji; Silver Bay;, Grand Rapids;
SITES FOR Koochiching Roseau County Beltrarni County Lake County Itasca County
GEOGRAPHIC County ,.
COVERAGE** (Region 1) (Region 3) (Region 3) (Region 1) (Region 1) .,
'Sampling locations were initially selected randomly from each MPCA administrative region. All minor civil'
divisions in a region were separated into One of five tiers based on 1994 estimated population data, with tier one
having the hi~hest population cenm-s and tier five having the lowest. One site was randomly selected from each
population tier in each lV[PCA region. The random selection process is descn'bed in the work. plan for the
.Statewide Air Toxics Monitoring Study. This random selection of sites will allow the MPCA to make inferences
about ambient air concentrations of pollutants in other rural areas, towns, and cities that are not included in the
study from the statistical properties of the data that will be collected from the randomly selected sites.
** However, the use of a random selection process to arrive at the selected sampling sites resulted in some large
geographic areas of the northern part of the state thai did not have sampling sites. To address this, five
additional sites were chosen to give better geographical coverage to the northern one-third of the stale. The
additional skes wer~ selected based on their geographic location in the northern pan of the state and their
population.
SUv=Bay
REGION 1
)ulu~h c~
2
REGION 3
l~doudy selected sit~s
Sims selected to provid~
geographic disu-ibu~ion
Minnesota Pollution Control Agency state,vide air toxics monitoring network
for volatile organic compounds, aldehydes and particulate metals.
Statewide Air Toxics M ,ring Study - Site Selection Results
I MPCA County House- Log(iwe) [Iog(iwe) MPCA Cumula- random random year to
Region MCD (City/Township) Pop. holds +1 +1] Region rive % qulntile .number no.2 sample
1 AITKIN WAGNER TOWNSHIP 280 109 #N/A 280 0.0077 99.59 5 0.9988 0.8036 1
1 ST. LOUIS HIBBING 17,964 7,486 19.2897 346,519 9.5147 55.63 3 0.2275 0.7927
..... 1 ST. LOUIS 'DULUTH 85,7461 34,995 19.5878 1,679,576 46.1176 46.12 1 0.5792 0.1751 3
1 ST. LOUIS VIRGINIA 9,232 4,313 19.7618' 182,441 5.009z 66.70 4 0.8987 0.1479 4
1 ST. LOUIS DULUTH
85,746 34,995 19.5878 1,679,576 46.1176 46.12 I 0.5792 0.0587 5
2 MORRISON LITTLE FALLS 7,595 3,0161 19.1369 145,344 3.8289 48.46 3 0.6962 0.9888 1
_ 2 SHERBURNE ELK RIVER 12,811 4,370 16.5251 211,703 5.5770 36.32 2 0.8392 0.8115 2
2 STEARNS ST CLOUD 50,143 18,800 18.539' 929,606 24.4890 24.49 1 0.36651 0.3879 3
2 WRIGHT ST MICHAEL 3,049 995 18.1521 55,346 1.4580 73.43 4 0.9698 0.2959
2 CROWWlNG FORTRIPLEY 90 35 #N/A 90 0.0024 99.95 5 0.9900 0.2450 5
3 DOUGLAS ALEXANDRIA 8,2511 3,667 19.9199 164,359 5.846' 52.20 3 0.5864 0.3805 1
.. 3 ..OTTER TAIL FERGUS FALLS .. 12,596---"5,22---~ 19.927----'---~ 251,004 8.9280 32.47 2 0.3610 0.2559
3 DOUGLAS BRANDON TOWNSHIP 613 206 #N/A 613 0.0218 95.34 5 0.9966 0.2404 3
3 O'1'~ ~-R TAIL PERHAM 2,204 96' 19.7540 43,538 .1.5486 77.69 4 0.8671 0.I701 4
3 CLAY MOORHEAD
33,618 11,798 19.6874' 661,850 23.5416 23.54 1 0.6896 0.0134 5
4 PIPESTONE .PIPESTONE 4,559 1,931 18.8913 86,125 4.0263 55.85 3 0.9222 0.6347 1
4 _YELLOW MEDICINE GRANITE FALLS 3,049 1,306 19.0074 57,954 2.7093 75.99 4 0.9582 0.3564 2
4 SWIFT HOLLOWAY 120 55 #NIA 120 0.0056 99.86 5 0.9982 0.3379
4 McLEOD HUTCHINSON ' 12,174 4,822 19.5224 237,666 11.1107 27.67 2 0.7476 0.1371 4
4 KANDIYOHI WILLMAR 1----8,54"---~,18~ 1-'--'~'.09-'-~7 354,11-------~ 16.554-----'~--16.5--~'---~--- ~J.2554 0.1178 5
5 GOODHUE LEON TOWNSHIp 946 308 #N/A 946 0.0130 * 97.63 5 0.9873 0.8123 1
5 OLMSTED ROCHESTER 76,865: 30,820 20.43'12 1,570,448 21.5117 21.51 1 0.3276 0.6671 ;.,
5 WINONA WiNONA 25,805 9,595 20.1619 520,277 7.1267 37.36 2 0.8629 0.5148 3
5 FREEBORN ALBERT LEA 18,338 7,588 18.8454 345,586 4.7338 57.95 3 0.9482 0.4233 ,1
5 NICOLLET NORTH MANKATO
.~;.~ ~., ..... ~.-,,.,~., .... ~ ....... 11,183 4,259 18.0356 201,692' 2.7627 75.18 4 0.9738 0.2011 5
6 HENNEPIN PLYMOUTH 57,391 20,856 18.8492 1,081,773 2.7157 45.29 3 0.9806 0.5949
6 :HENNEPIN MINNEAPOLIS 366,480 160,453 20.3698, 7,465,108 18.7406 18.74~ 1 0.0140 0.4038
6 WASHINGTON WEST LAKELAND TOWNSHIP 2,362 731 18.4534 43,587 0.1094 98.71 5 0.9981 0.3235 3
6 RAMSEY ST PAUL 271,660 110,347i 20.8602 5,666,882 14.2263 32.97 2 0.5619 0.3196
6 DAKOTA APPLE VALLEY
'".*..~ ~,-4 ......... 39,188 12,981 15.5729 610,272 1.5320 67.51 4 0.9892 0.1677
MPCA
3/18/96
List of the Air Toxic Pollutants included in the Statewide Air Toxics Monitoring Study
Volatile Org~anic
Compounds Determined by EPA Method TO-14
1. Benzene 13. 1,2-Dichloropropane 25. 1,1,!-Tdchlomethane
2. Brom0methane 14. cis-l,3-Dichloropmpene 26. 1,1,2-Tdchloroethane
3. Carbon Tetrachloride 15. Wans-l,3-D/chloropropene 27. Tdchloroethene
4. Chlorobenzene I6. 1,2-Dichloro-l,l,2,2-Tetrafluoroethane 28. Tdchlorofluoromethane
5. Chloroform 17. Ethylben:,ene 29. 1,2,4-Trimethylbeazene
6. 1,4-Dichlorobenzene 18. Ethylene Dibromide 30. 1,3,5-Trimethylbenzene
7. m-Dichlorobenzene 19. Freon 113 31. 'o-Xylene
8. o-Dichlorobenzene 20. Hexachloro-l,3-Butadiene 32. m & l>-Xylene
9. 1,1-Dichloroethane 21. Styrene 33. Vinyl Chloride
I0. 1,2-Dichloroethane 22. 1,1,2,2-Tetrachloroethane 34. Vinylidine Chloride
11. cis-l,2-Dichloroethylene 23. Tetrachlomethylene
12. Dichloromethane 24. Toluene
Carbonyl Compounds Determined by EPA Method TO-II
1. Acetaldehyde 4. Butyraldehyde
2. Acetone 5. Crotonaldehyde
3. Benzaldehyde 6. Formaldehyde
7. Propionaldehyde
Particulate Metals and Other Compounds Determined by X-ray Fluorescence Analysis
1VIETALS METALS OTF~.R
1. Antimony (Sb) 15. Vanadium (V) 1. Barium (Ba)
2. Araenic (As) 16. Zinc (Zn) 2. Boron (B)
3. Cadmium (Cd) 3. Bromine (Br)
4. Chromium (Cr) RARE EARTH 4. Chlorine (CI)
5. Cobalt (Co) 1. Gallium (Ga) 5. Phosphorus (P)
6. Lead (lab) 2. Indium (In) 6. Selenium (Se)
7. Manganese (Mn) 3. Lanthanum (La) 7. Sulfur (S)
8.. Molybdenum CMo) 4. Palladium (Pd)
9. Nickel (NJ) 5. Rubidium (Kb) CRUSTAL EI,F, MZNTS
10. Silver (Ag) 6. Strontium (Sr) 1. Calcium (Ca)
11.. Tin (Sn) 7. Yttrium (Yb) 2. Iron (Fe)
12. Titanium (Ti) 8. Zirconium (Zr) 3. Potassium (K)
Minnesota Pollution Control Agency
June 1997
Facts about
The MPCA's Monitoring Program for
Toxic Air Pollutants
The Legislature has
authorized the Minnesota
Pollution Control Agency to
begin a statewide effort to
monitor the ambient air (the
outdoor air around us) for "toxic
air pollutants." The agency
began the program last year, and
is now malting plans for placing
the monitoring equipment in
fiscal year 1998, which begins in
July 1997.
During the last ten years,
concern has developed regarding
a long list of substances that may
be found in the air in smaller
quantities but may be more toxic
than the "criteria pollutants."
Although the original six
pollutants are also toxic in
sufficient quantities, for lack of a
better name, these other
pollutants are often referred to as
"toxic air pollutants."
What are toxic air
pollutants?
For many years, the MPCA and
similar agencies in other states
have routinely monitored for a
group of six air pollutants called
"criteria pollutants": carbon
monoxide, sulfur dioxide,
nitrogen oxides, particulate
matter (usually soot or dust),
ozone and lead. These are
substances that are found in air
emissions from many types of
sources and in relatively large
quantities. These pollutants are
hazardous to human health and
the environment, and the U.S.
Environmental Protection
Agency has established limits
(standards) for how much may
safely be found in the air around
us -- the ambient air.
The EPA has identified 188
toxic air pollutants as "hazardous
air pollutants" (HAPs) and is
developing regulations for them.
However, there are a large
number of other toxic air
pollutants for which there are no
regulations and yet these other
toxic air pollutants have been
found in ambient air in studies
conducted in urban areas in other
states.
Why are we monitoring for
toxic air pollutants?
Many questions remain about
how much people are exposed to
toxic air pollutants in the
outdoor air in Minnesota and
whether these concentrations
pose a potential public-health
risk.
Printed on paper containing at least 10 percent fibers
from paper recycled by consumers.
Because not all of the substances
result from human activities, we
need to know what would be
considered the "natural" or
"background" level. How much
are people in communities of
various sizes exposed to? Which
pollutants are likely to present the
greatest risk? What kinds of air-
pollution sources need to be
controlled?
State and federal regulations to
require pollution control for toxic
air pollutants are beginning to be
established through the
provisions of the 1990 Clean Air
Act Amendments. However,
establishing these regulatory
requirements is a slow process
and it is unknown how much
these federal regulations will
reduce ambient-air concentrations
of toxic air pollutants.
In addition to the federal
program, pollution-control
requirements exist now for solid-
waste incinerators and for the
substances that also contribute to
smog. The MPCA also includes
requirements to control toxic air
pollutants in some air-emissions
permits, on a case-by-case.basis.
It is important to find out whether
these pollutants pose potential
risks to human health and if there
is a need for these pollutants to
be regulated further.
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What does the MPCA plan
to do?
Our plan is to sample for a
number of toxic air pollutants in
seven randomly selected
communities every year for five
years. We are selecting a cross
section of communities across
the state so that by the end of the
study we will have data that
represent the extent of toxic air
pollution in all types of areas.
A group of environmental
scientists from the University of
Minnesota is assisting the
MPCA in planning and carrying
out the study. In addition,
Minnesota Department of Health
staff, technical experts
representing industry and a
representative of the Minnesota
Center for Environmental
Advocacy are reviewing v~ork
plans, providing feedback to the
MPCA on the study, and they
will review future reports.
At the conclusion of the five-
year study, the MPCA will
prepare a report that compares
the ambient-air data in one paxt
of the state with the ambient-air
data found in other areas of the
state. The report will also
include a preliminary exposure
assessment of potential health
risks from selected toxic air
pollutants.
The MPCA will use this report
to determine if additional
follow-up monitoring is required
in any particular community. This
report will also be sent to the
Legislature for its potential use in
planning any future legislation.
Where are the monitors?
During the first year of the study,
the monitors were located in
Alexandria, International Falls,
Leon Township in Goodhue
County, Little Falls, Pipestone,
Plymouth and Wagner Township
in Aitldn County. The agency will
be able to report on the
monitoring after all the data are in
and have been quality-controlled
and analyzed.
MPCA staff are now beginning to
seek suitable future sites for the
monitoring equipment in the next
communities: Elk River, Fergus
Fails, Granite Falls, Hibbing,
Minneapolis, Rochester and
Warroad.. The actual monitoring
sites within each selected
community should satisfy the
following criteria:
· Be typical of the air that most
residents would breathe;
Be in a secure location, on a
rooftop or on the ground, free
of obstructions such as trees,
towers, mechanical systems;
such as air conditioners
· Have access to electrical
power;
· Have all-day access during the
entire year.
The monitoring sites will not be
located near known sources of
these air pollutants; that is not
the purpose of this study. The
types of places the MPCA has
located monitors in the past
include one-story rooftops of
government buildings and fire
stations. An ideal location
would be at a neighborhood
school. The equipment will be
placed on pallets and requires
about a 10 x 10 foot area.
The MPCA will contract with
local electricians to provide
power to the site and meet all
applicable electrical codes. We
will provide the property owner
with a lease and contract for the
equipment operation, if
necessary, and can be
responsible for all costs
associated with setting up the
site and for the utility costs. We
plan to occupy the site for only
a one-year time period, and
after that year the equipment
will be moved to another
community that has been
selected for inclusion in the
study.
How do the monitors
work?
Each site will be equipped with
samplers for volatile organic
compounds (VOCs), carbonyl
compounds such as
formaldehyde, and to collect
small particles. Each site will
collect a 24-hour sample every
six days. This will allow
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sampling to occur on every day
of the week during a one-year
time period.
Once set up, the instruments will
automatically start at the
prescribed time and collect a
sample for 24 hours and then
shut off. About 60 samples will
be collected at each site for
VOCs, carbonyl compounds, and
metals in the particulate
mater/al.
The site operator must prepare
the instruments for sampling by
placing new filters and VOC
canisters in the insmaments and
then collect the samples, f'fll out
some simple information and
ship them to the MPCA. MPCA
staff will collect the samples
themselves at as many sites as
possible. However, some private
operators will be needed for
some. of the sites, and the MPCA
will provide training and funding
for these private operators.
Volunteers are always welcome.
When the monitors be
installed?
Ideally, a new site is prepared 30
days in advance of the year-long
sampling period. Site preparation
includes constructing a site
platform or pallet, establishing
power and training an operator
(which should take just four to
six hours).
Since we have instruments for
only seven sites, at the end of the
year the sampling at each
location will end, and the
instruments will be moved to the
new sites. We hope the change-
over can take place over a two-
week per/od.
More questions?
For more information about the
toxic air pollutants study, please
contact either Don Bock in the
Air Analysis Unit at
(612) 296-7329 or Cliff
Twaroski in the Air Toxics Unit
at (612) 296-7757.
This information can be made available in other formats
including Braille, large type and audiotape. TTY users, call
(612) 282-5332.