ISD 112 EAW draft
EAW
NVIRONMENTAL SSESSMENT ORKSHEET
Note to preparers: This form is available at http://www.eqb.state.mn.us. will be
EAW Guidelines
available in Spring 1999 at the web site
. The Environmental Assessment Worksheet provides
information about a project that may have the potential for significant environmental effects. The EAW is
prepared by the Responsible Governmental Unit or its agents to determine whether an Environmental
Impact Statement should be prepared. The project proposer must supply any reasonably accessible data for
— but should not complete — the final worksheet. If a complete answer does not fit in the space allotted,
attach additional sheets as necessary. The complete question as well as the answer must be included if the
EAW is prepared electronically.
Note to reviewers:
Comments must be submitted to the RGU during the 30-day comment period following
notice of the EAW in the EQB Monitor. Comments should address the accuracy and completeness of
information, potential impacts that warrant further investigation and the need for an EIS.
1. Project title: New ISD 112 High School in Chanhassen
2. Proposer: ISD 112
Contact person: Steven Pumper
Title: Director of Finance and Operations
Address: 11 Peavey Road
City, state, ZIP: Chaska, MN 55318
Phone: 952-556-6261
Fax: 952-556-6269
E-mail: pumpers@district112.org
3 RGU: City of Chanhassen
Contact person: Robert Generous, AICp
Title: Senior Planner
Address: 7700 Market Boulevard, P.O. Box 147
City, state, ZIP: Chanhassen, MN 55317
Phone: 952-227-1131
Fax: 952-227-1110
E-mail: bgenerous@ci.chanhassen.mn.us
4. Reason for EAW preparation:
(check one)
X
EIS scoping Mandatory EAW Citizen petition RGU discretion Proposer volunteered
If EAW or EIS is mandatory give EQB rule category subpart number: 4410.4300, subpart 14.b.3
and subpart name: Industrial, commercial, and institutional facilities
Proposed project exceeds 300,000 square feet of new institutional construction.
5. Project location County: Carver County City/Township: City of Chanhassen
SectionTownshipRange
SE 1/4SW1/4 15 116 North 23 West and
SectionTownshipRange
NW 1/4 22 116 North 23 West
Attach each of the following to the EAW:
County map showing the general location of the project; (See Figure 1)
?
U.S. Geological Survey 7.5-minute, 1:24,000 scale map indicating project boundaries (photocopy
?
acceptable); (See Figure 2)
Site plan showing all significant project and natural features. (See Figure 3)
?
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6. Description
a. Provide a project summary of 50 words or less to be published in the EQB Monitor:
In order to accommodate projected growth, ISD 112 proposes to build a new high school in
Chanhassen to be located on undeveloped property northeast of County Road 18 (Lyman Boulevard)
and north of Hazeltine Lake. The proposed high school will be constructed to accommodate 2000
students, and related school developments will include adjacent parking and numerous athletic fields.
The school is projected to open in Fall 2009.
b. Give a complete description of the proposed project and related new construction. Attach
additional sheets as necessary. Emphasize construction, operation methods and features that will
cause physical manipulation of the environment or will produce wastes. Include modifications to
existing equipment or industrial processes and significant demolition, removal or remodeling of
existing structures. Indicate the timing and duration of construction activities.
The proposed project will be constructed on a land parcel approximately 94.8 acres in size, that is
generally bounded on the south and west by County Road 18 (Lyman Boulevard), on the north by the
Twin Cities and Western Railroad, and on the east by Bluff Creek (see Figure 4).
A total of one building will be constructed. The building will be 3 stories (portions) and have a
footprint of 242,400 square feet. A total of 1,153 automobile and 30 bus parking stalls are planned;
bituminous parking areas will be constructed for these areas that will encompass approximately
379,500 square feet (see Figures 5 and 6).
Traffic will enter and exit the proposed facility from Lyman Boulevard at three separate points. Related
to the project (but not part of the project) turn lanes in both directions will be added to the north
entrance to the facility and the intersections of Lake Hazeltine Drive and southbound Audubon Road,
and the Lake Hazeltine Drive intersection will be signalized. A traffic study was conducted as part of
the project environmental evaluation, and the results show that the level of service will be impacted
without roadway improvements.
Three wetlands exist at the site, totaling a total of 24.2 acres. A total of 1.8 acres of wetland are
anticipated to be impacted (filled) prior to construction activities. Mitigation measures will be
performed as required by Minnesota wetland rules and the City of Chanhassen.
Utility construction will include extensions for potable water, sanitary sewer, electrical power and
natural gas. All utility construction will be extensions from nearby existing connections. Storm water
runoff will be collected, detained and treated to preconstruction standards, and discharged to Bluff
Creek.
The property where the construction is proposed to occur is currently in agricultural use, and a remnant
farmstead (outbuildings only) on the southern portion of the parcel. The farmstead buildings will be
demolished according to state and local rules, and associated underground structures (wells, septic
system) appropriately abandoned.
Wastes generated during construction will include only unsuitable soils and normal construction debris
associated with new construction. Waste streams generated after school operations have begun are
anticipated to include primarily mixed municipal waste, with building maintenance activities anticipated
to generate minor amounts of regulated waste.
The proposed timing for the project envisions the start of construction in Spring 2007, with completion
by Fall 2009. Construction activity phasing is anticipated to be grading (Winter 2006), building
construction (Summer 2007), parking area and road construction (Fall 2007), and athletic field
construction (spring 2008).
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c. Explain the project purpose; if the project will be carried out by a governmental unit, explain the
need for the project and identify its beneficiaries.
The purpose of the project is to build a second local high school to accommodate observed and
projected increases in local population growth. The project will be carried out by Independent School
District 112, and the direct beneficiaries will be high-school aged students (grades 9-12) and their
families.
d. Are future stages of this development including development on any outlots planned or likely to
happen? __Yes _X_No If yes, briefly describe future stages, relationship to present project,
timeline and plans for environmental review.
N/A
e. Is this project a subsequent stage of an earlier project? __Yes _X_No
If yes, briefly describe the past development, timeline and any past environmental review.
N/A
7. Project magnitude data
Total project acreage 94.83 acres
Number of residential units: unattached N/A attached: N/A maximum units per building: N/A
Commercial, industrial or institutional building area (gross floor space): 405,000 total square feet
Indicate areas of specific uses (in square feet):
Office: N/A Manufacturing: N/A
Retail: N/A Other industrial: N/A
Warehouse: N/A Institutional: 405,000 square feet
Light industrial: N/A Agricultural: N/A
Other commercial (specify): N/A
Building height: 3 Stories If over 2 stories, compare to heights of nearby buildings:
The proposed structure is generally consistent with existing construction in the vicinity of the site. The
nearest buildings visible from the site are the back sides of one- to two- story buildings across Lyman
Boulevard in the industrial park, and two-story residential housing approximately 1/4 mile to the east
of the site (across the Bluff Creek Preserve). Residential housing to the north of the site is generally
screened from view from the site by trees along the railroad tracks.
8. Permits and approvals required. List all known local, state and federal permits, approvals and
financial assistance for the project. Include modifications of any existing permits, governmental review
of plans and all direct and indirect forms of public financial assistance including bond guarantees, Tax
Increment Financing and infrastructure.
Unit of government Type of application Status
Federal
US Army Corps of Engineers Section 404 Wetland Permit To be submitted
State
Minnesota Pollution Control Agency NPDES Construction To be submitted
Stormwater Permit
Sanitary Sewer Extension To be submitted
Permit
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Unit of government Type of application Status
Minnesota Department of Health Water Main Extension Permit To be submitted
Well Sealing Notification To be submitted
Regional
Metropolitan Council Sanitary sewer connection permit To be submitted
County
Hennepin County Work Within Right of Way To be submitted
Approval
Local
Riley/Purgatory/Bluff Creek Watershed District Grading Permit To be submitted
City of Chanhassen Rezoning Approval To be submitted
Conditional Use Permit To be submitted
Site Plan Review To be submitted
Wetland Conservation Act Permit To be submitted
Variance To be submitted
Demolition Permit To be submitted
Building Permit To be submitted
ISD 112 Bonding Referendum Election 11/7/2006
9. Land use. Describe current and recent past land use and development on the site and on adjacent
lands. Discuss project compatibility with adjacent and nearby land uses. Indicate whether any potential
conflicts involve environmental matters. Identify any potential environmental hazards due to past site
uses, such as soil contamination or abandoned storage tanks, or proximity to nearby hazardous liquid
or gas pipelines.
Current land use within the parcel boundaries is agricultural (row crops) and grasslands/wetlands, and
a remnant farmstead currently exists in the southern portion of the site. Review of historical aerial
photographs also document this land use to at least 1940. The residence previously located at the
farmstead was reportedly removed from the site when the electrical substation was constructed in 1988.
Historical land use of adjacent lands is primarily agricultural, with commercial/light industrial development
beginning to the south of the site in the late 1980s and early 1990s. Residential development is has been
constructed to the north and east of the site.
The proposed project does not raise any significant compatibility issues with nearby non-residential land
uses, as this nearby land use (commercial/warehouse) does not store or use large amounts of hazardous
substances that could be released during an emergency situation. Also, the proposed school is considered
compatible with nearby residential land uses.
A buried 12-inch liquid petroleum pipeline, owned by Magellan Pipeline, approximately bisects the site,
running mostly east-west across the site. Although no buildings will be constructed within the pipeline
right-of-way, the presence of this operating liquid pipeline presents a potential hazard both during
construction and ongoing building operations. Care will need to be taken during construction operations to
make all construction contractor employees aware of the presence of the pipeline. This will be done during
the construction phase through use of pipeline location highlighting on all relevant construction plan sheets,
construction field flagging of the pipeline, preparation of a spill contingency plan, and ongoing awareness
at project management meetings during construction. After construction, the pipeline location will be
identified by physical signage, notations on building layouts, and training of building grounds employees.
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Additionally, the school will develop an emergency evacuation/response plan to plan for unforeseen
emergency situation related to a pipeline release.
Potential environmental hazards were identified in a Phase 1 Environmental Site Assessment (ESA)
performed in 2004 at the property (related to the remnant farmstead) in the form of regulated waste
associated with planned demolition (e.g. asbestos, lead paint, waste fluids and containers), possible historic
on-site disposal of farmstead wastes, and possible fill materials that may contain regulated substances.
Also, the Phase 1 ESA identified an unused above-ground storage tank at the remnant farmstead; it is
possible that soil and/or groundwater contamination exists as a result of past uses of this tank. Detailed
investigation of these potential hazards was not performed as a part of the Phase 1 ESA; these hazards will
be further evaluated (and mitigated, if necessary) as part of demolition activities and prior to site grading
activities in accordance with Minnesota Pollution Control Agency (MPCA), Minnesota Department of
Health (MDH) and local rules.
10. Cover types. Estimate the acreage of the site with each of the following cover types before and after
:
development
Before After
Types 1-8 wetlands 24.6 acres 26.4 acres
Wooded/forest 2.53 1.4
Brush/Grassland 5.1 6.5
Cropland 62.42 0
Lawn/landscaping 0 33.53
Impervious surfaces 0.18 24.5
Other (storm ponds) 0 2.5
TOTAL 94.83 94.83
If Before and After totals are not equal, explain why:
Not applicable
11.Fish, wildlife and ecologically sensitive resources
a. Identify fish and wildlife resources and habitats on or near the site and describe how they would
be affected by the project. Describe any measures to be taken to minimize or avoid impacts.
The U.S. Fish and Wildlife Service was contacted for review of federally listed threatened or
endangered species within the project site. According to the U.S. Fish and Wildlife Service, no
federally listed or candidate species are documented on the site.
A majority of the project site has been disturbed by cultivated agricultural land uses (currently used for
corn production). There are clusters of trees and shrubs on the property. These wooded areas provide
habitat for birds (blue jays, warblers, nuthatches, chickadees, grackles, crows) and for small and larger
mammals (small rodents, rabbits, squirrels, foxes, raccoons, opossum, deer) that are typically found in
and at the edge of the urban landscape.
Four wetland areas have been delineated on the Site (see Figures 7 and 8). Wetland “A” is a 6.03-acre
Circular 39 Type 2, 3, 6, and 7wetland complex located along the northeastern border of the site.
This wetland is dominated in the swales by reed canary grass. Willows and cattails are also found
in this wetland complex. In the shrub and wooded portion of the swales, box elder, cottonwood,
elms, and willows are dominant. Wetland “B” is a 17.94-acre continuation of wetland “A” which is
located along the southeastern border of the site with a finger that extends across the site and to near
Lyman Boulevard. Wetland “C” is a 0.23-acre Circular 39 Type 2 wet meadow located along the
southwestern border of the site. This wetland is dominated by a near monotypic stand of reed canary
grass. Portions of this wetland also contain cattails, willows, shrubs, and deciduous trees. Wetland
“D” is a 0.4-acre area along Lyman Boulevard in the central portion of the site and is dominated by
corn and nightshade with reed canary grass in the ditch.
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The wetlands provide habitat for some aquatic life (such as invertebrates and amphibians) and provides
edge habitat for the other bird and mammal species mentioned previously. The wetlands also provide
seasonal habitat for waterfowl.
Additionally, a 1.50-acre conservation easement connects wetlands “A” and “B” along the eastern
border of the site. The project site is adjacent to and west of one of the three parcels of Bluff Creek
Preserve and is adjacent to and west of a City park. According to the City of Chanhassen, the preserve
creates an important wildlife travel corridor in the center of the community.
The proposed project site is near Bluff Creek. Efforts to minimize impacts to the creek are explained
in detail in Question Number 17.
The proposed development scenario consists of more intensive land uses compared to the existing land
uses. The more intensive uses will result in changes in vegetative cover (see question 10), including
conversion of much of the agricultural land and some of the wooded portions of the study area to
suburban cover. The majority of the wetland areas and the entire conservation easement will be
preserved. Portions of wetlands A and B will be filled for a practice field, an access road, a parking
and to create a walking path between the bus parking area along the southwest corner of the high
school to the existing pedestrian path in the adjacent park; however, mitigation will occur on site.
Mitigation locations are planned in the extreme southeast corner of the property as well around the
four storm water ponds that will be constructed on-site near the existing wetlands (using Public Value
Credits). Public Value Credits may be issued due to the “e stablishment or preservation of upland
buffer areas contiguous to replacement wetlands, restoration of partially drained wetlands, and creation
of stormwater detention areas.” See Minn. R. 8420.0541, subp. 6. Some of the vegetation impacts
will be mitigated by plantings of trees, shrubs, and perennial plants planned as part of the proposed
development. The developer will work with City staff to identify the appropriate quantities, types,
and locations of plantings during City staff review of the landscape plan for the proposed project.
Existing wildlife populations may concentrate at the remaining “natural” habitat areas on the site
(declining in numbers if they stay in the remaining, smaller natural areas on the site), or they may
adapt to the new suburban cover types, or may migrate to nearby natural habitat locations.
During construction, appropriate setbacks will be maintained and silt fencing will be installed on the
portions of the wetlands with the potential to receive construction runoff. The installation of silt fence
will minimize the effects of sedimentation and ensure that the wetlands are not altered as a result of the
construction.
b. Are any state-listed (endangered, threatened or special concern) species, rare plant communities
or other sensitive ecological resources such as native prairie habitat, colonial waterbird nesting
colonies or regionally rare plant communities on or near the site?
X
__Yes __No
If yes, describe the resource and how it would be affected by the project. Indicate if a site survey of the
resources has been conducted and describe the results. If the DNR Natural Heritage and Nongame
Research program has been contacted give the correspondence reference number: ERDB# 20070286
Describe measures to minimize or avoid adverse impacts.
The Minnesota Department of Natural Resources was contacted for review of their Natural Heritage
Database (ERDB# 20070286 ). That review is included as Attachment A. They have indicated that
there are no known occurrences of rare species or native plant communities in the project area.
12. Physical impacts on water resources. Will the project involve the physical or hydrologic alteration —
dredging, filling, stream diversion, outfall structure, diking, and impoundment — of any surface waters
such as a lake, pond, wetland, stream or drainage ditch? _X_Yes __No
If yes, identify water resource affected and give the DNR Protected Waters Inventory number(s) if the
water resources affected are on the PWI. Describe alternatives considered and proposed mitigation
measures to minimize impacts.
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Of the total 24.6 acres of wetland present within the project boundary, approximately 1.8 acres of
wetland are proposed to be filled for an access drive, parking lot and a practice field (see Figure 9).
None of the impacted wetland areas are MN DNR-protected waters (see Figure 10). The impacted
wetlands are labeled as portions of Wetlands A and B on Figure 8 (described in more detail in
Question 11 above), and the areas proposed to be filled are shown on Figure 8. A total of 3.6 acres
of wetland area are proposed to be created as on-site mitigation (at a 2:1 ratio) for these filled areas,
and these wetland impacts will be permitted through MN Wetland Conservation Act processes locally
administered through the City of Chanhassen.
13. Water use. Will the project involve installation or abandonment of any water wells, connection to
or changes in any public water supply or appropriation of any ground or surface water (including
dewatering)? _X Yes __No If yes, as applicable, give location and purpose of any new wells; public
supply affected, changes to be made, and water quantities to be used; the source, duration, quantity
and purpose of any appropriations; and unique well numbers and DNR appropriation permit numbers,
if known. Identify any existing and new wells on the site map. If there are no wells known on site,
explain methodology used to determine.
The proposed project will require connection to the City of Chanhassen’s municipal potable supply
system. The City of Chanhassen obtains its potable supplies from 10 water supply wells that produce
water from the Prairie du Chien/Jordan (7 wells), and glacial sediment aquifers (3 wells), and are
permitted by the MN Department of Natural Resources under appropriation permit number 816089.
The City has indicated that its potential aquifer supply, and pumping and storage capacity is adequate
to accommodate these increased demands without additional wells or off-site infrastructure
improvements.
Water usage in the school building for the proposed facility is estimated at 50,000 gallons per day
during the school year (approximately 10 million gallons per year); this total number is based on the
MN Plumbing Code requirement of 25 gallons per person per day for this type of facility. Additional
water will be used for exterior (irrigation) uses to maintain the grounds and athletic fields. Interior
water use will be at its peak during the school year (September through May), and drop off
significantly during the remaining summer months.
It is currently unknown whether construction dewatering will be necessary during excavation of the
proposed building and related utility construction. Given the site topography, building locations
and subsurface geology, is appears unlikely that groundwater will be encountered and thus require
dewatering of excavated areas. Temporary ponded water from precipitation events during construction
will require removal; this dewatering activity does not require MN DNR Appropriation permitting, but
will be addressed (and potential impacts designed to be mitigated) within the MPCA-required
Construction Storm Water Pollution Prevention Plan (SWPPP).
14. Water-related land-use management district. Does any part of the project involve a shoreland zoning
district, a delineated 100-year flood plain, or a state or federally designated wild or scenic river land
use district? _X_Yes __No
If yes, identify the district and discuss project compatibility with district land use restrictions.
The eastern part of the site abuts the FEMA-delineated 100-year floodplain along Bluff Creek, as well
as the City of Chanhassen’s Bluff Creek Overlay District (see Figure 11). However, no buildings will
be constructed within these areas, and construction activities will be outside these boundaries. The
required Conditional Use Permit application will detail conformance with setback, impervious surface,
and natural habitat preservation requirements of the overlay district. Therefore, no incompatibilities
are anticipated with these land use restrictions.
There are no state- or federally-designated wild or scenic river land districts in the project area.
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15.Water surface use. Will the project change the number or type of watercraft on any water body?
__Yes _X_No If yes, indicate the current and projected watercraft usage and discuss any potential
overcrowding or conflicts with other uses.
The proposed project is not anticipated to change the number or type of watercraft on any body of
water.
16. Erosion and sedimentation. Give the acreage to be graded or excavated and the cubic yards of soil
to be moved: 65 acres; 730,000 cubic yards. Describe any steep slopes or highly erodible soils and
identify them on the site map. Describe any erosion and sedimentation control measures to be used
during and after project construction.
The upland areas of the site are mapped by the USDA as Hayden loam (Ha designation on Figure 12)
with slopes varying from 2 to 40 percent. These soils are considered well-drained, but listed as
severely erodible, and the steepest slopes occur on the eastern portion of the site. Thus, these soils
must be stabilized once disturbed to prevent erosion from precipitation runoff.
At lower elevations in the upland areas are Terril loam (Te designation on Figure 12) soils with slopes
varying from 0 to 6 percent; these soils are moderately well-drained and are not readily erodible. Also
present at these lower elevations are Lester loam (La designation on Figure 12) with 2 to 6 percent
slopes, and which is moderately well drained and is has a moderate erosion hazard.
At lower elevations at the site, soils are listed as deep peat and muck (Pd designation on Figure 12);
these areas represent the larger wetland areas to the east of the site. Typically flat-lying, these
sediments are prone to erosion of disturbed.
17. Water quality: surface water runoff
a. Compare the quantity and quality of site runoff before and after the project. Describe permanent
controls to manage or treat runoff. Describe any stormwater pollution prevention plans.
Current storm water flows from the site occur as overland flow to ditches and adjacent wetlands.
Currently in agricultural use, there are no known measurements of water quality of storm water flows
at the site, nor does the current land use require formal storm water management or permitting.
City of Chanhassen rules require that permanent storm water flows to receiving surface waters meet
predevelopment flow water quantity and quality standards. National Urban Runoff Program standards
were used to develop storm water pond sizing; a total of four storm water ponds to be located at the
site are shown on Figure 13. Site ponds were also sized to accommodate the planned road upgrades to
Lyman Avenue. Therefore, potential water quality and quality impacts from permanent storm water
flows will be mitigated through design and construction of storm water improvements specified by
City rules.
Potential storm water impacts to Bluff Creek during construction will be controlled and mitigated
through the MPCA Construction Storm Water Pollution Prevention Plan (SWPPP) permitting process
for the project. The project proposer must complete and implement a SWPPP required under MPCA
rules. The SWPPP plan will contain details of proposed storm water protection measures, including
Best management Practices such as crushed rock aprons at entrances and exits, perimeter silt fence,
stock pile protection, construction staging, and temporary basins.
b. Identify routes and receiving water bodies for runoff from the site; include major downstream
water bodies as well as the immediate receiving waters. Estimate impact runoff on the quality of
receiving waters.
The receiving water for storm water runoff from the site is Bluff Creek. Since the water quantity is
anticipated to be equal to that of the previous uses, there are no expected negative impacts to the
receiving waters from increased volumes. As discussed above, water quality is anticipated to be
improved compared to previous uses, and so no water quality impacts to receiving waters are
anticipated.
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18. Water quality: wastewaters
a. Describe sources, composition and quantities of all sanitary, municipal and industrial wastewater
produced or treated at the site.
Only sanitary wastewater is anticipated to be generated upon completion of the proposed
project. Estimated sanitary wastewater produced from the site after operation is anticipated to
be 50,000 gallons per day, based upon estimated indoor water consumption.
b. Describe waste treatment methods or pollution prevention efforts and give estimates of
composition after treatment. Identify receiving waters, including major downstream water bodies,
and estimate the discharge impact on the quality of receiving waters. If the project involves on-site
sewage systems, discuss the suitability of site conditions for such systems.
No wastewater treatment will take place on-site; sanitary wastewater will be conveyed to the MCES
Blue Lake wastewater treatment plant for treatment and discharge.
c. If wastes will be discharged into a publicly owned treatment facility, identify the facility, describe
any pretreatment provisions and discuss the facility's ability to handle the volume and composition
of wastes, identifying any improvements necessary.
Wastewater flows will be conveyed to the MCES Blue Lake wastewater treatment plant, which
ultimately discharges to the Minnesota River. The treatment plant discharges are regulated by NPDES
Permit # MN 0029882 issued to MCES by the Minnesota Pollution Control Agency. Representatives
of MCES familiar with the Blue Lake plant were contacted, and stated that the existing treatment
facility has the current capacity to treat the proposed flows, and that the type and volume of these
additional flows will not jeopardize the discharge limitations of the facility. No treatment plant or
collector interceptor improvements are planned due to the anticipated increased flows from the
proposed project.
d. If the project requires disposal of liquid animal manure, describe disposal technique and location
and discuss capacity to handle the volume and composition of manure. Identify any improvements
necessary. Describe any required setbacks for land disposal systems.
No liquid animal manure will be generated or need disposal as part of the proposed project.
19. Geologic hazards and soil conditions
a. Approximate depth (in feet) to ground water: 25 minimum: 5
Average depth to bedrock: minimum: 375 feet; average: 425 feet
Describe any of the following geologic site hazards to ground water and also identify them on the site
map: sinkholes, shallow limestone formations or karst conditions. Describe measures to avoid or
minimize environmental problems due to any of these hazards.
The bedrock geology beneath the site is characterized as the eastern portion of a buried bedrock valley
that drains to the south to the Minnesota River. Elevations of the bedrock surface range from
approximately 500 feet above mean sea level (under the western portion of the site) to near 600 feet
above mean sea level under the eastern portion of the site. The buried bedrock valley contains
subcrops of the Ordovician Prairie du Chien Group, the Cambrian Jordan Sandstone, and the Cambrian
St. Lawrence and Franconia Formations (in descending order). No shallow limestone formations exist
beneath the site, not are karst conditions or sinkholes known at the site or in the area (see Figure 14).
The glacial materials overlying the bedrock are mapped as glacial till deposited by the Des Moines
lobe (see Figure 15). This till material is characterized as yellow-brown loam to clay loam, containing
sand and pebbles. These deposits also may contain pockets of silt, sand or gravel. These glacial
deposits are not generally known to be associated with subsurface hazards.
Groundwater under the site occurs both in the glacial materials and in the underlying bedrock aquifers.
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Groundwater in the glacial materials occurs at shallow depth due to the relatively impermeable nature
of the glacial sediments, and gradients are anticipated to generally reflect the surface topography. No
domestic water wells are known to be present at or near the site that produce from glacial materials.
Bedrock aquifers are the primary source of potable water for the residences and businesses in the area.
These wells are over 200 feet deep, and their static water levels are approximately 100 feet below
ground surface. The thickness and composition of the glacial sediments overlying the bedrock aquifers
serve as natural protection for these aquifers from releases at or near the land surface.
b. Describe the soils on the site, giving NRCS (SCS) classifications, if known. Discuss soil granularity
and potential for groundwater contamination from wastes or chemicals spread or spilled onto the
soils. Discuss any mitigation measures to prevent such contamination.
The details of the soils mapped at the site are described in Question 16 above and are shown on Figure
12. The Hayden series soils, which cover much of the upland area of the site, are generally range from
silty sand to lean clay in composition and have a permeability of under 0.2 inches per hour. Their
well-drained character makes them somewhat susceptible to infiltration of surface contaminants. The
other yupland soil series (Terril and Lester series) are moderately well-drained and are also susceptible
to infiltration of contaminants.
Mitigation measures will include preparation and implementation of a Construction Storm Water
Pollution Prevention Plan (SWPPP) during construction activities, as well as development of an
emergency contingency plan after construction is completed.
20. Solid wastes, hazardous wastes, storage tanks
a. Describe types, amounts and compositions of solid or hazardous wastes, including solid animal
manure, sludge and ash, produced during construction and operation. Identify method and location of
disposal. For projects generating municipal solid waste, indicate if there is a source separation plan;
describe how the project will be modified for recycling. If hazardous waste is generated, indicate if
there is a hazardous waste minimization plan and routine hazardous waste reduction assessments.
Demolition waste from the remnant farmstead will be generated prior to construction, which will
consist of concrete, steel, and various building materials. Asbestos-containing materials (if present)
will be inventoried and will be removed prior to demolition and disposed of appropriately in a licensed
landfill. Lead-based paint and other hazardous building materials that may exist (e.g. fluorescent
lamps, light ballasts, mercury switches, appliances, fuel, paint, etc.) will also inventoried and will be
removed prior to demolition and disposed of according to state and federal rules. Nonhazardous
demolition waste will be disposed of in a demolition landfill.
Excavation, removal, and disposal of any contaminated soils (if encountered) will be done in
accordance with prior MPCA review and approval.
Solid waste generation for the completed project will consist almost exclusively of mixed municipal
waste generated by school activities. Volumes of municipal waste are estimated at 10 cubic yards of
non-compacted waste per week; waste collection will occur six times per week during the school year.
Mixed municipal solid waste will be hauled to a sanitary landfill by licensed waste haulers. Source
separation (recycling) of cardboard and recyclable solids (commingled paper and consumer
recyclables) from the mixed municipal waste stream will be performed under a plan to be developed by
the School district. These recycled materials will be picked up weekly.
b. Identify any toxic or hazardous materials to be used or present at the site and identify measures
to be used to prevent them from contaminating groundwater. If the use of toxic or hazardous
materials will lead to a regulated waste, discharge or emission, discuss any alternatives
considered to minimize or eliminate the waste, discharge or emission.
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No toxic materials are anticipated to be present at the site in any significant quantities during or after
construction. Small amounts of hazardous materials (e.g. cleaners, boiler chemicals, herbicides, paints,
and maintenance supplies) will be present and will likely create a small waste stream of hazardous
waste. These materials will be stored, used, and disposed of according to state and local rules.
Hazardous materials, in the form of fuel, vehicle-related materials, and certain construction materials
will be on-site during construction, but will be present in relatively small quantities and will be stored
in conformance with regulatory requirements.
c. Indicate the number, location, size and use of any above or below ground tanks to store petroleum
products or other materials, except water. Describe any emergency response containment plans.
The project is planned to utilize two petroleum storage tanks (for fuel oil and diesel fuel) to support
facility operations. The fuel oil tank will be a 10,000-gallon underground fiberglass tank with
electronic monitoring and double-walled underground piping. This fuel will be piped to the boilers
and is designed to serve as backup fuel for the boilers in case of natural gas supply interruption.
The diesel fuel tank will be a 2,700-gallon, skid-mounted above-ground storage tank, piped to a
1,500 KW diesel-powered electrical generator to be used to provide backup electrical power should the
normal power supply be interrupted.
Emergency response plans for releases from either fuel storage tank will be included within the
emergency evacuation/response plan. Also, due to the capacity of the diesel fuel storage tank, a Spill
Prevention Control and Countermeasures (SPCC) Plan will be prepared and implemented.
21. Traffic. Parking spaces added: 1,153
Existing spaces (if project involves expansion): 0
Estimated total average daily traffic generated: 3,420 trips
Estimated maximum peak hour traffic generated (if known) and its timing: 1,408 from 7:30-8:30 a.m.
Provide an estimate of the impact on traffic congestion on affected roads and describe any traffic
improvements necessary. If the project is within the Twin Cities metropolitan area, discuss its impact
on the regional transportation system.
A detailed Traffic Impact Study (TDI, Inc., dated October 2006) was prepared for the proposed
Chanhassen High School and is here incorporated by reference. The following discussion is based on
the findings contained in the Traffic Impact Study (see Figures 15-18).
Traffic Congestion
Based on the calculations in the Traffic Impact Study, the daily traffic volumes on the roads affected
by the development will be:
Daily Traffic Volumes (with the existing roadway network)
2010
Existing No-2010 2030
Roadway (2005) Build Build Build
Lyman Blvd west of Galpin Blvd 5,600 7,200 8,100 11,300
Lyman Blvd northwest of Lake Hazeltine Dr 5,000 6,500 7,700 10,800
2
Lyman Blvd west of Audubon Rd South 9,100 11,000 13,100 18,300
122
Lyman Blvd east of Audubon Rd South 13,400 16,200 18,300 25,600
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Lyman Blvd east of Audubon Rd North 11,100 14,500 15,900 22,300
Galpin Blvd north of Lyman Blvd 3,200 3,500 3,800 5,300
112
Audubon Rd South south of Lyman Blvd 12,400 15,100 15,300 21,400
Audubon Rd North north of Lyman Blvd 3,600 4,700 5,400 7,600
1
Daily traffic volume is near capacity
2
Daily traffic volume is over capacity
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Traffic Improvements
Based on the analysis in the Traffic Impact Study, the existing roadway network will accommodate the
traffic generated by the proposed Chanhassen High School if the following mitigation measures are
implemented by opening day of the school:
Construct a traffic signal at the Lyman Boulevard/Lake Hazeltine Drive intersection.
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Modify the existing signal at the Lyman Boulevard/Audubon Road South intersection for the
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addition of a north leg to the intersection.
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Construct the following turn lanes:
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Approach Left Turn Lane Right Turn Lane
Southbound Lyman Blvd at North School Access Bypass lane
Northbound Lyman Blvd at North School Access 200 feet
Westbound North School Access at Lyman Blvd Through lane becomes 300 feet
turn lane
Southbound Lyman Blvd at Lake Hazeltine Dr 200 feet
Northbound Lyman Blvd at Lake Hazeltine Dr 200 feet
Eastbound Lake Hazeltine Dr at Lyman Blvd 100 feet
Westbound Lake Hazeltine Dr at Lyman Blvd 300 feet Build
through/right
Eastbound Lyman Blvd at Audubon Rd S 200 feet
Westbound Lyman Blvd at Audubon Rd S 200 feet
Northbound Audubon Rd S at Lyman Blvd Build to add through
lane
Southbound Audubon Rd S at Lyman Blvd 200 feet Build
through/right
In addition, operation of the Lyman Boulevard/Gaplin Boulevard and Lyman Boulevard/Audubon
Road North intersections should be monitored for potential improvements. Both intersections will
likely require traffic signals and additional turn lanes in the future.
Impacts to Regional System
The following corridors will be at or over capacity in the future whether or not the high school is built.
They should be monitored and appropriate improvements should be made when needed.
Lyman Boulevard east of Lake Hazeltine Drive.
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Audubon Road South - south of Lyman Boulevard.
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22. Vehicle-related air emissions. Estimate the effect of the project's traffic generation on air quality,
including carbon monoxide levels. Discuss the effect of traffic improvements or other mitigation
measures on air quality impacts. Note: If the project involves 500 or more parking spaces, consult
EAW Guidelines about whether a detailed air quality analysis is needed.
Traffic on the area roads will increase (details described in the TDI, Inc. traffic study) even under the
no-build scenario. However, traffic volumes will also increase due to construction of the proposed
project. Consequently, there will be increased vehicle-related air emissions particularly during peak
trip generation times (7:30-8:30 a.m. and 2:30-3:30 p.m.).
Five intersections were examined to determine their “Level of Service” (LOS). LOS A represents light
traffic flow, while LOS F represents heavy flow (over capacity conditions). Generally, air quality is
only impacted if an intersection is severely congested (LOS E or LOS F). Based on the predicted
morning and afternoon peak traffic hours, if the Lyman Blvd/Galpin Blvd intersection and the Lyman
Blvd/Lake Hazeltine Drive intersections are signalized, it is not anticipated that the traffic increase due
to the school will exceed air quality standards.
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23. Stationary source air emissions. Describe the type, sources, quantities and compositions of any
emissions from stationary sources of air emissions such as boilers, exhaust stacks or fugitive dust
sources. Include any hazardous air pollutants (consult EAW Guidelines for a listing) and any
greenhouse gases (such as carbon dioxide, methane, nitrous oxide) and ozone-depleting chemicals
(chloro-fluorocarbons, hydrofluorocarbons, perfluorocarbons or sulfur hexafluoride). Also describe
any proposed pollution prevention techniques and proposed air pollution control devices. Describe the
impacts on air quality.
Heating of the buildings will be done through use of three natural-gas-fired hot water boilers, each
rated at 8.4 MBH (total of 25.2 million BTUs/hour). The boilers are designed to run on natural gas or
#2 fuel oil (for emergency heat). An on-site back-up power generator will be powered by diesel fuel,
but its use, and therefore its emissions, will be very limited. No significant hazardous air pollutants are
associated with this use, and consequently no air pollution control devices are planned to be installed.
24. Odors, noise and dust. Will the project generate odors, noise or dust during construction or during
operation? _X_Yes __No If yes, describe sources, characteristics, duration, quantities or intensity
and any proposed measures to mitigate adverse impacts. Also identify locations of nearby sensitive
receptors and estimate impacts on them. Discuss potential impacts on human health or quality of life.
(Note: fugitive dust generated by operations may be discussed at item 23 instead of here.)
Minor amounts of fugitive dust are anticipated to be generated by equipment during construction.
Odors may also be generated from construction equipment exhaust. Equipment will include trucks,
backhoes, scrapers, bulldozers, loaders, and compressors. Waste will be controlled by weekly clean-up
of the construction site, and water or other dust suppressants will be used to control airborne dust when
necessary. Noise, dust and odors from construction activities will be limited in duration, and will be
controlled by limiting the hours and days of construction operation to those permitted by local
ordinances.
Once project construction is completed, it is anticipated that the project will not generate significant
dust beyond current site conditions since all disturbed areas of the site will be covered with either hard
surface or turf/landscaping.
After construction activities are completed, noise will be generated by increased traffic. To a lesser
extent, outdoor events (e.g. athletic events) taking place at the site will create noise but the hours of
such noise generation will be controlled by the school event staff. Noise from both sources above will
generally be during daylight or early evening hours.
Given the location and topography of the proposed site, there are no significant sensitive receptors
immediately adjacent to the site for either traffic noise or event noise. Therefore, there are no noise
mitigation measures proposed.
25. Nearby resources. Are any of the following resources on or in proximity to the site?
X
Archaeological, historical or architectural resources? __Yes __No
X
Prime or unique farmlands or land within an agricultural preserve? __Yes __No
X
Designated parks, recreation areas or trails? __Yes __No
X
Scenic views and vistas? __Yes __No
X
Other unique resources? __Yes __No
If yes, describe the resource and identify any project-related impacts on the resource. Describe any
measures to minimize or avoid adverse impacts.
Designated parks, recreation areas or trails?
The project site is adjacent to and west of one of the three parcels of Bluff Creek Preserve (at the
northern portion of the site) and is adjacent to a park (at the southern portion of the site). As
mentioned in question number 11a, a walking path will be created to link the high school to the
existing trail in the park area.
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Scenic views and vistas:
The construction of this project will present a new feature to the view from and to Bluff Creek
Preserve as the current project site is predominantly developed as cultivated agricultural land. In order
to minimize impacts to scenic views and to preserve open space, the majority of the parking lots will
be located along Lyman Boulevard, thus maintaining a visual corridor along the northern portion of
the site.
Other unique resources
Two large wetland complexes are present along the eastern portion of the project site. Potential
impacts to this wetland complex are discussed in items 11, 12, and 17. Additionally, Bluff Creek is
near to the proposed project site. Bluff Creek is a unique natural resource. In order to preserve the
quality of this resource, the project is designed to not only meet existing standards for storm water and
construction water runoff, but the project is designed to exceed these standards. Additional protective
measures will be added during construction, and a treatment-train approach will be used to ensure that
Bluff Creek will not be adversely impacted by the project. (See question #17 for additional
information.)
26. Visual impacts. Will the project create adverse visual impacts during construction or operation? Such
as glare from intense lights, lights visible in wilderness areas and large visible plumes from cooling
X
towers or exhaust stacks? __Yes __No
If yes, explain.
Visual impacts will occur from the presence of the school and associated structures in a previously
predominantly agricultural area. Visual impacts will also occur from building, parking lot, field, and
stadium lighting. The City’s Zoning Ordinance contains information that addresses outdoor lighting.
This project will adhere to the lighting conditions contained in the zoning ordinance.
27. Compatibility with plans and land use regulations. Is the project subject to an adopted local
comprehensive plan, land use plan or regulation, or other applicable land use, water, or resource
management plan of a local, regional, state or federal agency?
_X_Yes __No. If yes, describe the plan, discuss its compatibility with the project and explain how
any conflicts will be resolved. If no, explain.
The City of Chanhassen has an adopted local comprehensive plan. The current zoning of the site is A2
(Agricultural Estate District); the site area is shown as Office/Industrial on the Chanhassen 2020 Land
Use Plan. Rezoning is required for the proposed project, although the rezoning will be generally
consistent with the land use designation (see Figures 19 and 20).
The City of Chaska also has an adopted local comprehensive plan. The current zoning of that portion
of Chaska immediately adjacent to the site is Planned Industrial Development, (PID-1); this area is
shown as Industrial on the Chaska 2020 Land Use Plan. This industrial park is already essentially built
out, and so no near-term land use changes for this area are anticipated. The proposed project is not
inconsistent with the adjacent Chaska land use plans (see Figures 21 and 22).
The City of Chanhassen also has an approved and adopted water resource plan, and the proposed
project will be subject to the requirements of this plan, as well as other development ordinances
contained in the City Code. There are no conflicts anticipated.
28. Impact on infrastructure and public services. Will new or expanded utilities, roads, other
infrastructure or public services be required to serve the project? _X_Yes __No. If yes, describe the
new or additional infrastructure or services needed. (Note: any infrastructure that is a connected
action with respect to the project must be assessed in the EAW; see EAW Guidelines for details.)
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Road improvements (turn lanes) will be constructed in concert with the proposed project to serve the
project and accommodate increased traffic volumes. These improvements are described in the traffic
study (TDI, Inc., dated October 2006), and will be constructed by the City of Chanhassen. These
improvements were planned by the City prior to the proposed project, and their construction in
association with the proposed project reflects mainly an accelerated construction schedule for the
improvements due to the proposed project rather than improvements that will only serve the project.
Connections to the City’s potable water and sanitary system will be made from nearby existing
connections; no significant City infrastructure projects will be necessary to provide access for these
connections.
No other public infrastructure or services are required to serve the proposed project.
29. Cumulative impacts. Minnesota Rule part 4410.1700, subpart 7, item B requires that the RGU
consider the "cumulative potential effects of related or anticipated future projects" when determining
the need for an environmental impact statement. Identify any past, present or reasonably foreseeable
future projects that may interact with the project described in this EAW in such a way as to cause
cumulative impacts. Describe the nature of the cumulative impacts and summarize any other available
information relevant to determining whether there is potential for significant environmental effects due
to cumulative impacts (or discuss each cumulative impact under appropriate item(s) elsewhere on this
form).
No cumulative impacts are anticipated as a result of the proposed project. The proposed project is not
anticipated to induce any specific related development or impacts that will cause cumulative impacts.
Also, as the adjacent lands are either fully developed or guided by land use planning, development of
nearby properties will develop only as currently planned by the City of Chanhassen.
30. Other potential environmental impacts. If the project may cause any adverse environmental impacts
not addressed by items 1 to 28, identify and discuss them here, along with any proposed mitigation.
There are no known or anticipated environmental impacts that have not been discussed elsewhere in
this EAW.
31. Summary of issues. Do not complete this section if the EAW is being done for EIS scoping; instead,
address relevant issues in the draft Scoping Decision document, which must accompany the EAW. List
any impacts and issues identified above that may require further investigation before the project is
begun. Discuss any alternatives or mitigative measures that have been or may be considered for these
impacts and issues, including those that have been or may be ordered as permit conditions.
The most significant potential issues associated with the proposed project are:
Traffic:
1. There will be temporary impacts to vehicle traffic due to construction-related activity
during excavation, construction materials delivery and storage, and tie-ins to existing subgrade
utilities. These predicted vehicle traffic impacts will last for much of the construction life of the
project, and will be geographically associated with the phasing of construction. Some of the
potential impacts can be mitigated through implementation of City ordinances relating to hours
and days of operation, noise, nuisance conditions, etc.
Post-construction traffic impacts are anticipated after the project is constructed, and are detailed in
the traffic study. These impacts are anticipated to involve slight decreases in Level Of Services
(LOS) in the project vicinity. Plans for mitigation of these impacts include adding turn lanes and
signalizing of nearby intersections.
No additional traffic impacts or issues have been identified that require further investigation.
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Wetland Impacts
2. : A total of 1.8 acres of wetlands are proposed to be filled as part of the project.
Mitigation measures will include on-site replacement (new wetland creation as well as public
value credits) according to MN Wetland Conservation Act rules, which are administered by the
City of Chanhassen.
No additional wetland impacts or issues have been identified that require further investigation.
Storm Water Runoff
3. : There is potential for impacts to Bluff Creek and associated wetlands from
temporary and permanent storm water runoff. Potential impacts from temporary storm water
runoff include those from sediment loading during and immediately after construction. These
potential impacts will be mitigated through MPCA storm water and local permitting.
Potential impacts from permanent storm water runoff include those from performance of storm
water engineering design and construction. These potential impacts will be mitigated through
local review of design plans, as well as on-site inspections during construction.
No additional storm water impacts or issues have been identified that require further investigation.
RGU CERTIFICATION.SIGNED
The Environmental Quality Board will only accept Environmental
Assessment Worksheets for public notice in the EQB Monitor.
I hereby certify that:
The information contained in this document is accurate and complete to the best of my knowledge.
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The EAW describes the complete project; there are no other projects, stages or components other
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than those described in this document, which are related to the project as connected actions or
phased actions, as defined at Minnesota Rules, parts 4410.0200, subparts 9b and 60, respectively.
Copies of this EAW are being sent to the entire EQB distribution list.
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Signature Date
Title
Environmental Assessment Worksheet
was prepared by the staff of the Environmental Quality Board at
the Administration Department. For additional information, worksheets or for EAW Guidelines, contact:
Environmental Quality Board, 658 Cedar St., St. Paul, MN 55155, 651-296-8253, or
http://www.eqb.state.mn.us
04539\ISD 112 EAW draft 10.27.06
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