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May 28, 2009 Bonestroo
Melanie Curtis
Planning &Zoning Coordinator
City of Orono
Post Office Box 66
Crystal Bay, MN 55323
Re: 2687 Wayzata Boulevard
File No. 000139-09000-2
Building Permit No. 2009-00122
Dear Melanie:
We have reviewed the grading plan and stormwater management plan dated 5-19-09 for parking
lot expansion and rain garden at 2687 Wayzata Boulevard. Our review includes a compliance
check for Chapter 79 of Orono's Land Use Code. We have the following comments:
• Concrete curb and gutter should be installed around the perimeter of the parking lot.
• The discharge rates for the rain garden (4.63 cfs 10-year and 6.79 cfs 100-year
event) exceed those of the existing conditions (2.96 cfs 10-year and 4.50 cfs 100-
year event). All runoff rates for proposed conditions should be less than or equal to
existing condition rates.
• Geotechnical reports for the adjacent Crystal Bay Business Center indicated that
parking lot pavement sections include a 12-inch select granular, 6-inch aggregate
base, and 3-inch bituminous pavement section for normal duty pavement. Heavy
duty pavement (drive lanes of the parking lot) was to have 24-inches select granular,
8-inches of aggregate base, and 4-inches of bituminous. We would recommend
using these pavement sections or have the applicant submit a geotechnical report
stating that the 6-inch aggregate base and 2.5-inch bituminous is sufficient.
• Draintile should be provided for the rain garden.
• The applicable code section is 79-7(c)(2) for all commercial or industrial sites in
which land disturbance activities fill or excavate more than 100 cubic yards.
• To bring this submittal in to compliance with the ordinance, the following information
should be provided separately or on the grading plan.
o Phasing plan. A phasing plan shall be provided that clearly indicates the
areas in the order they are to be disturbed and restored. The phasing plan
shall consider minimization of area and duration of exposed soil and unstable
conditions, minimization of the disturbance of natural soil cover and
vegetation, erosion and sediment control measure installation, weather
conditions and the schedule for temporary and permanent restoration. The
area and duration of each phase shall be indicated on the plan.
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City of Orono Page 2
09-00122 May 28,2009
o Standard detail sheet. A standard detail sheet shall be provided that consists
of applicable construction details for approved erosion and sediment control
measures as developed by the City. Other techniques may be used upon
prior approval by the City with details provided by the designer.
o Specifications. Written specifications for land disturbance activities such as
product descriptions, installation and maintenance procedures required by
the applicant to carry out the project in accordance with this Chapter.
o Temporary erosion and sediment control plan: Indicate the location of
perimeter controls, construction fence, temporary sedimentation basins, inlet
protection, areas to be seeded, areas to be mulched or blanketed, location of
construction waste control (dumpsters, chemical storage, concrete washout,
portable restroom facilities, etc.)and all other required temporary erosion
and sediment control measures. This plan shall also indicate staging of
temporary erosion control measures.
o Permanent erosion and sediment control plan: Indicates areas to be seeded
and sodded, sediment ponds, storm sewer systems and all other required
permanent erosion and sediment control measures. Permanent storm water
pollution controls including, but not limited to ponds,vegetated buffers and
structural measures shall be designed and constructed in accordance with
other Chapters of the City Code and requirements of other agencies having
jurisdiction.
o Narrative: Describes, at a minimum, the nature of construction activity,
person(s) responsible for inspection and maintenance of site erosion and
sediment control including contact information, project phasing, schedules,
along with the timing, installation and maintenance of erosion and sediment
control measures and specifications necessary to carry out the project.
o The$2,000 financial guarantee identified in Section 79-7(b)(2) should be
sufficient for this project.
If you have any questions, please call me at(651) 604-4894.
Yours very truly,
Darren Amundsen
Cc: Tom Kellogg