2 Chanhassen High School
CHANHASSEN PLANNING COMMISSION
REGULAR MEETING
DECEMBER 5, 2006
Chairman McDonald called the meeting to order at 7:00 p.m.
MEMBERS PRESENT:
Jerry McDonald, Kathleen Thomas, Debbie Lloyd, Dan Keefe, Kurt
Papke, Mark Undestad, and Kevin Dillon
MEMBERS ABSENT:
None.
STAFF PRESENT:
Kate Aanenson, Community Development Director; Lori Haak, Water
Resources Coordinator; and Alyson Fauske, Assistant City Engineer
PUBLIC PRESENT FOR ALL ITEMS:
Janet Paulsen 7305 Laredo Drive
Rick Dorsey 1551 Lyman Boulevard
Tom Devine 7640 South Shore Drive
PUBLIC HEARING:
CHANHASSEN HIGH SCHOOL, REQUEST FOR INTERIM USE PERMIT TO GRADE
SITE IN PREPARATION OF DEVELOPMENT ON PROPERTY LOCATED NORTH
OF LYMAN BOULEVARD, SOUTH OF THE TWIN CITIES AND WESTERN
RAILROAD, AND WEST OF BLUFF CREEK, ZONED A2, AGRICULTURAL ESTATE
DISTRICT AND REVIEW AN ENVIRONMENTAL ASSESSMENT REVIEW
WORKSHEET. APPLICANT ANDERSON-JOHNSON ASSOCIATES, INC.,/
INDEPENDENT SCHOOL DISTRICT 112, PLANNING CASE 06-35.
Public Present:
Name Address
st
Steve Miller 244 1 Avenue, Minneapolis
Mike Spack 3268 Xenwood Avenue So, St. Louis Park
Jay Pomeroy 7575 Golden Valley Road, Minneapolis
Steve Pumper 11 Peavey Road, Chaska
Paul Schlueter 427 Campfire Curve, Chaska
Phil Standafer 8767 Valley View Place
Al Gomez 8748 Valley View Place
Chairman McDonald: Continuing from our last meeting, Chanhassen High School had presented
for us an Interim Use Permit to grade the site in preparation of development of the property that's
located on Lyman Boulevard, south of the Twin Cities and Western Railroad. At that time we
had tabled the, this application because a question came up concerning is it being built into a
bluff or not on the property. Staff then was tasked with going back to evaluate this and to
Planning Commission Meeting - December 5, 2006
present us with a clarification as to whether or not there was a bluff involved within this
development. Staff, are you prepared?
Aanenson: Yes, thank you. Chairman McDonald, members of the Planning Commission. As
you've indicated you tabled this item for the staff to look at the slope issue. I apologize we didn't
put this in. We had made that determination and didn't put that information in there previously
so again I want to have Lori Haak go through the definition of slope and then I'll go through the
process that we went through to determine whether or not it was a bluff. So I'll let her take a
minute to explain.
Haak: Chair and Planning Commissioners. The bluff ordinance looks a little complicated at first
but actually is quite simple. The objective is to of course preserve any steep slopes and by
definition bluffs are 25 or more feet from toe to top, and they're 30% or greater slope over that
rise. So again, just going back to a rhythm to say I guess rise over run gives you the percentage
of the slope. And the third provision as outlined in the staff report basically exempts any areas
that may be a bench within that area so if you have a slope that starts quite steep and then levels
off and then rises again, those areas if they extend for less than 18% over 50 feet or more are
exempted from that. In this case we don't have that entering into play, but that is another part of
the definition.
Aanenson: Included in your packet was some aerial photography so what I'd like to do is just
kind of go through that to show you the history of this property and interpretation. As with all
areas that may be qualified for slopes in the city, we do look at kind of the natural features.
Typically when we see slopes or, they're also in areas that are heavily wooded, undisturbed
because they haven't been able to be touched because of their location and the steepness. So with
this we've got some different aerial photography that I'll go through. First, with everybody
following along a frame of reference here. This is Lyman Boulevard. The school site. The
subject school site and the railroad tracks. Again, because the photography I'm going to show
you is a little bit hard to see, I'll click the current frame of reference. So this is 2006. Again the
subject site so the frame of reference, Lyman Boulevard and the railroad tracks. I'm going to
show you this stand of trees because this stand of trees is one constant that you can see in the
project itself in the different aerial photography so we'll go back all the way to 1940, and I think
you might have to zoom on this a little bit more Nann. This is black and white. This is in blue
you can see the subject site. There's a road going through the middle of that. Kind of that, it was
defined as the, what was questioned as a possible bluff site. Again here's the trees for the frame
of reference and Lyman Boulevard and the railroad tracks. So this is photography from 1940.
Going back to, or coming forward to 1963. Again Lyman Boulevard and the railroad tracks
again for frame of reference. This is the trees. You can see pretty much the creek is farmed, or
what could be of the creek is predominantly farmed. A little piece is hard to see somewhere in
this area. It's getting a little bit more pronounced in here. Moving forward to 1979. You can see
it's getting more pronounced. It's farmed all the way around it. There isn't significant vegetation
on it. And then moving forward as I showed you in today, 2006. This would be the area. It's
continued to grow. And you can see that the farming practices have been removed from the
creek, or the flood plain itself and subdivisions have occurred. So with that, as Lori defined the
definition, we took the steepest area and created that toe, top of slope and took that percentage.
Anything under 30% and we do have that, that opinion has been given by the City Attorney. If
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Planning Commission Meeting - December 5, 2006
it's under 30% it does not meet the definition of the slope. So with that, and I'm sorry we didn't
have for you at the last meeting. How we got to that conclusion and didn't think it would come
up but with that, following on page 2 of the staff report. Based on the geographic information,
taking that slope and the results of the data, we believe that there is not the definition of a bluff.
And that is the only area that comes close to meeting the 30%. For other reasons, as you can see,
it was previously farmed, a lot of that area. So with that we are recommending approval with the
issues as stated on the beginning of the staff report. The Interim Use Permit and the
Environmental Assessment Worksheet review, and with the conditions of approval of followed
on page 8 and 10 in the staff report. And I do believe you left the public hearing open at your
last meeting so.
McDonald: Yes we did and at this point I guess I would pick up at that point. If there was
anyone that wishes to come forward and make comments. What I would ask is that we do not go
back over issues that were brought up before because those have been more or less addressed or
settled. If there's anything new that anyone wishes to bring up, if they would come forward.
Please do so. State your name and address and then whatever comments you may have, address
them to the Chair.
Al Gomez: I'm back again. My apologies. Al Gomez, 8748 Valley View Place in Chan. I'm
the property that's across the bluff. I guess pretty difficult to see in the pictures and understand
what part of it becomes wetland versus what part of it becomes the actual bluff itself that were or
were not yet farmed. Obviously the colored pictures show more of a color differentiation, which
would show alteration in elevation which I'm not sure you would get out of a black and white.
My father in law happens to be a farmer in the area and can go back to 1910 and state every
farmer that's farmed that property. From Dethelm to Koskie, Carver Bongard, and again that
terrain is the same as it's been all along. So the topography may show something different but
how much of that is color. The other thing is, at least from where I sit, my back window looks
directly up the bluff. Depending on, I guess I need to understand depending on where you start
the lowest part of elevation, what's 30 degrees? If it's the middle of the wetlands, I'm not sure
that that's fair. If it's the end of the wetlands where the actual bluff begins, I'm having a hard
time, and Phil my neighbor, are having a hard time believing that that's 30 degrees or lower.
Additionally, and again minor topic but I emailed Bob Generous, obviously the mail indicated if
you have questions, please email him. I emailed him asking for a copy of the bluff ordinance
and did not get a reply. I subsequently placed a phone call into Bob saying again no indication
that you didn't get my email, but I wanted to follow up again. Hope you got my email with the
information I sent you about the farmers. Can I get a copy of the ordinance to take a look at it
since we too have not seen it and I did not get a reply. So again, I'm assuming that's what staff is
there for is to help us citizens get to that information so that we can in turn be more educated
with the decisions that you make.
Aanenson: Can I just ask, when did you try to contact Bob?
Al Gomez: On Monday and Tuesday.
Aanenson: I apologize. Just for the record Mr. Chair, Bob's been out sick the last 2 days. I'm
sorry.
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Planning Commission Meeting - December 5, 2006
Al Gomez: Well, then somebody should be checking his emails or something.
Aanenson: Correct.
Al Gomez: The other question that I don't think was answered last time, that I would like to ask
again. We did bring up the question of are the developers or is the school district prepared to
build on this property other than if it's leveled, and that was not addressed. So has the
assumption been all along, or been an understanding that concessions were going to be made to
be able to level this bluff prior to the discussion around the bluff ordinance for them to build on
this property?
Aanenson: I'm not sure I understand the question. I think even if it is guided and also industrial,
I think there was, no matter what use was to go on that site, there was an assumption that there
would be grading on the site. I mean we have that with every industrial park so, depending on
the foot print of the building, depending on the overall plat layout, there is an inherent
assumption that there's going to be grading on the site.
Al Gomez: To the degree of the 25 feet and the numbers where.
Aanenson: Well I would assume if it was compatible to an industrial park, it might not one
single user might have been that big but in compilation, there would probably be the same
amount of quantities. I don't know if you want to add anything to that Alyson.
Fauske: The challenges of the site are, there is a large grade differential from where they want
their building pad to, down to the creek area. Certainly the pipeline presents a huge challenge
for the grading operations and just the use that they've proposed on the site. The area that they
need to provide all the facilities for the school have indeed presented itself as the Planning
Commission sees here.
Al Gomez: So the gas line is pushing the fact that the, to have the use of the land they would
have to grade it? I'm assuming that's something they took into consideration or studied prior to
buying the property. So as they bought the property, was there an understanding that there was
going to be approval to level that bluff? And to your point that in previous considerations that
there was an understanding that there would be grading, again all I got, I have to go by is we've
had Nancy Mancino on our property when we discussed high density developments in that area
and the indication from Nancy, who was the mayor at the time, was that that was protected by
the bluff ordinance so there was not discussions around there would be grading. From my
experience.
McDonald: I guess as far as any conversations about this particular piece of property, that's
beyond the scope of what we actually know or had presented to us. That would probably be
between the developers and whoever bought the property but what they've brought before us is
mainly a plan and what they're asking for is permission to do grading based upon the ordinance
and that's all that we can actually look at. Anything beyond that, what I would suggest is, you
could talk to them and find out but I'm unaware of anything.
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Planning Commission Meeting - December 5, 2006
Aanenson: Let me just clarify too. When the school district bought this property they didn't
know what it was going to be. It could have been a middle school or a high school. That
decision was made at a later date, you know when they actually did their analysis. When the first
acquisition, they were under study. We always said it was proposed secondary schools how it
was notified, because they didn't know themselves until they went through their study exactly
what it was going to be so, to say we always knew it was going to be a big high school isn't a fair
statement.
Al Gomez: And again for clarity for us, the slope and from where it's measured. To the top of
the bluff is at the bottom of that hill, not beyond and into the wetland.
Aanenson: That's correct.
Al Gomez: Okay. And that shows to be less than 30 degrees.
Aanenson: Correct.
Al Gomez: Okay. Because again, we're having a tough time with that because we look at it
every day.
Aanenson: Understood, yeah. Yeah.
McDonald: Okay, does anyone else wish to come forward and make comment? Okay seeing no
one come forward, I close the public meeting and I bring the discussion back up before the
commissioners. Kevin, I'll start on my left.
Dillon: Yeah, it's kind of like the person who was just speaking alluded to, there seems to be the
potential for some subjectivity as to how you were to measure this hill, or bluff. You know I
mean, you know where you exactly say the bottom is. It levels up and the toe of it is and you
know, I mean the top part I suppose is a little bit easier to define. The highest point of it but I
mean when we're talking you know 29.9 degrees and 29.7 degree slopes, I mean you know that
little bit of subjectivity may play a role so, two people may come to a different conclusion on
that. So I mean, just based on that, I mean it's a real close call so. The other thing is, I
apologize. I was not at the last commission meeting. I couldn't be here so, what's the, like the
Reader's Digest version of the city code on the bluffs? You can't built on one?
Aanenson: That's correct.
Dillon: Okay. That's the only question I have for right now.
McDonald: Mark?
Undestad: No.
McDonald: Debbie? No? Okay. Kurt?
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Planning Commission Meeting - December 5, 2006
Papke: Kind of following up on Commissioner Dillon's line of reasoning there. In this particular
case, since we're so close, obviously people will ask the question. How did you exactly come to
that answer? Did you get two people independently verify it? Could you speak to, since it is so
close, what you did to make sure that the number was that on.
Aanenson: Sure. All slopes, if you physically walk and find that natural break, as Lori
indicated, where that natural start the rise is, would be. So that's one indicator. And there was 2
or 3 people that did the independent calculation. And also on the school district, which I didn't
show that one but if you look at the school district plans, they also have their own, this is the
City's data but we also used, and that's in your packet. I didn't go through that one but the school
district also has their grading plan. The existing grades that they put on there, and that also cross
checked and was a couple percentage point different. So we did take the steepest portion of it, so
yes. We had a couple people look at it. And field check.
McDonald: Okay. Dan.
Keefe: Just one more question on that. I mean when I look at the picture, the 2006 slope
analysis I see, it does rise above the 972 and then it does go below the 906. But what you're
saying is that you must start somehow do this, kind of like that.
Aanenson: Yep, that's correct. Right.
Keefe: I don't know how you do it but…
Aanenson: And that's the point that Lori went through when she was looking, when she was
explaining it to you. You kind of have to find that, you can always find one little segment that
may be kind of, so you have to kind of find that natural, where that segment is.
Keefe: Well, but that's the problem because you're at 29.9. I mean if you're 20 it wouldn't be
you know.
Aanenson: Yes.
Keefe: And if by ordinance it's 30%, you know.
Haak: But to be fair, I'm sorry.
Keefe: It could be 28 too and…
Haak: And this has gone both ways for the City. You know we've had 30.1 and we've had 29.9
and we've made decisions either way.
Keefe: Right.
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Planning Commission Meeting - December 5, 2006
Haak: So it is very much a call where we've had subdivisions that have come in with 29.9 slopes
and we've you know, there's no preservation under the code with that and, but with you know
30.1 it is. So and again, we've had that interpretation that it's just a matter of where you draw
that line and the line is 30.
Aanenson: And just like a wetland delineation, we field check those too.
Keefe: It just seems that you know to me that, since we've gone to the extent of putting the
definition of bluff and the emphasis on trying to, to save bluffs, that we're at one which is close.
We would err on the side of determining that it is a bluff versus determining that it isn't a bluff
since we've gone, any thoughts on that?
Aanenson: Lori raised the argument that it's come up as the City Attorney's done it, if you're at,
with the 30.1, then you're penalized. I'm so close so you have to, it's what it is. It's that elevation
and it gets, it goes both ways. Whether it's a penalty or a favor. So, and also, you know part of
looking at this, when we put together the bluff ordinance city wide, because originally it was just
down on the river bottom. Was to save those areas where there was some of those natural
features and looking at the past practice of this property, it's not tied, really definitely. It's
farmed behind it and it still is. It's not really tied into, when you look at other areas with
significant stands of trees, which we were trying to accomplish. Where there's been erosion.
The thing has grown. The anomaly in itself and what we're trying to preserve some of the
natural landform. So could it have grown or risen based on farming practices? There's a lot of
rational you know thinking that you have to kind of put into it. That's why we went back and
pulled out some of those aerials for you to show you kind of that frame of reference. Because
most of the stuff that we have preserved is, I would say the significant portion of it, there are
some bluffs that have eroded down in the river. Overlooking the river, but.
Keefe: They're no longer natural…
Aanenson: Exactly, but a lot of it is just what we're trying to preserve is some of those, that
natural topography and this is a knoll. I wouldn't say it's connected to. You know the biggest
feature we're trying to save there, and what we're working with the school district on is the
increase quality and function of the creek itself. And you can see on that one part, where Lori's
already worked to do the remandering on that very treed area and continue that as we move
through the creek corridor.
McDonald: Okay.
Audience: Can I quick ask two questions?
McDonald: At this point the public meeting is closed and we're really at a point of deliberating
on this. If you have questions concerning this, what I would suggest is after the vote, you can
certainly talk to staff afterwards, and again this is going to City Council. I guess based upon
that, the only comments I really have for this is, what's actually before us is strictly a grading
permit at this point. It has nothing to do with building. All of that will have to come back before
us at some other time so, based upon that, you know I have no further comments to make and.
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Planning Commission Meeting - December 5, 2006
Papke: I thought we were just doing questions at this point. Are we at the point of comments?
As well.
McDonald: Yep, go ahead.
Papke: Okay. Like I said before, before we head into a vote. As I was reading through this I
was really trying to think about you know, is this the right or the wrong thing to do and in all the
years I've lived in Chanhassen I drive by the high school, the existing Chaska High School very
frequently, and one of the things that struck me is, I don't think there's any facility in a city that's
used more than the school. Every time I drive by Chaska High School there's hundreds of cars in
the parking lot. There's people going in and out for sporting events and activities and school and
you know, and I think there's, and since we're going to have to live with this for 50, 100 years,
however long this school site lasts, I think it does, as I thought about it, it really made sense to
me that we really should optimize the utility of this land and yes, we're going to, there's going to
be a tremendous amount of dirt moved and it is from an ecological perspective in kind of a
sensitive area. But I think 10, 15 years from now I think we'll be very happy that this was very
well graded and very easy to get in and out of because thousands and tens of thousands of trips
are going to be made in and out of here throughout a given year so. Although I certainly
understand the people who live in the area are concerned with the aesthetics and ecological
aspects of it, I think those have been reasonably considered under the ordinance and I think, you
know as I really thought about it, this seemed to be the right thing to do for the community for
the long run so.
McDonald: Does anyone else wish to make comments? Kevin?
Dillon: Yeah, just what is the down side to grading the bluff? Is it loss of an aesthetic, beautiful
thing or is it going to cause a runoff problem or is it just.
Aanenson: It's part of where the building footprint would be so it dramatically changes the
location of the footprint of the building and useable area. Because it's not just the bluff area, but
to stay away from it, because you can't go behind it. For usability. Because of this footprint. So
it's kind of the form of this building. The larger footprint that's, and you've got space behind it.
So if you were doing a small, smaller building or something like that, you could accomplish
maybe something on the site.
Dillon: Well I get the benefit of that but what's the down side to the bluff? You know I mean.
McDonald: Well part of the problem is, from last week, there is a pipeline I guess due north.
They cannot move in that direction so they are bound by that pipeline, which is off quite a bit
from the railroad tracks. So that one constraint. And the next constraint is to get a building of a
certain size, and in order to do that, the design that comes out of this is more of a walkout type of
a design in order to get the square footage required for the school, so those are some of the
limitations that are faced as part of the design. There isn't a lot of movement within that
particular piece of property.
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Planning Commission Meeting - December 5, 2006
Dillon: Well the maybe just for a little extra context here, for those that you know raised the
issue last week and had a problem with this, what were they saying was, why were they opposing
the extra grading for the bluff?
McDonald: Well a lot of that.
Dillon: Why are we here this week?
McDonald: A lot of that, well what it got into was the design of the building and the effect upon
homes across the creek side. And what that was going to do as far as changing the view.
Changing aerodynamics was brought up. As far as winds and you know things that could
happen across the valley there. Those were brought up, but then the issue of the bluff was
brought up and at that point there was not sufficient information to say whether or not they met
the requirements of the bluff ordinance, so it was tabled based upon that.
Papke: Typically if we reflect back on some of the cases we've had in front of us, Settlers Ridge
West probably being the one that stands out in my brain the most, it was erosion control tends to
be the major issue. And in this particular case, since there's been how many years of plows
going over that soil, it doesn't seem to be you know as critical an issue as it was along the
Minnesota River bluff. You know which is kind of the typical case we run into.
Keefe: Let me ask you a question. Say this came in at 31%, would we be looking at a variance
on this?
Aanenson: Yeah.
Keefe: More than likely we would be.
Aanenson: Right, we would have recommended that, right.
Keefe: So if we think of it in those terms, you know. You know I supposed you'd have to
demonstrate a hardship associated with bringing a variance in place on that. I'm not sure what
the hardship would be associated with this.
Aanenson: Well we'd go back to the same analogy that we just gave with the past farming
practices, there's not a significant natural feature on top of it and those same sort of rationale.
McDonald: Yeah, I mean obviously one of the hardships that we have is the fact of the path, of
the pipeline which goes through there which severely limits any building in that particular
direction, and at this point they are as far as they can go. Now what you're left with, you can put
athletic fields and those things or aprons going up to those fields. That's what you can use for
that space. So there are limitations with the property. Does anyone else wish to make
comments? Okay.
Larson: Yeah.
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Planning Commission Meeting - December 5, 2006
McDonald: Okay.
Larson: I'm just looking at the slope analysis here and I think they've been very generous in the
29.7 and as I'm looking at this, the steepest portion actually would be, let's see here. 50 feet.
Probably be a good 20 feet less than what they're showing so I'm thinking this 29% would really
be more, just based on looking at the severity of the slope, I'm thinking it'd be less than 29%. So
therefore as I said, I think the City kind of did the worst case scenario of a footprint, what do you
call it? Foot and top.
Aanenson: Toe.
Larson: Toe. Foot.
Aanenson: Toe and top, yeah.
Larson: So I mean, my thoughts are, it's actually less than 29.7 and therefore I guess I don't see a
problem with this.
McDonald: Okay. Well, if all the comments are complete, I'm ready to accept a motion on this
issue. What he's looking for is on page 8.
Undestad: Okay, I make a motion the Planning Commission recommends the City Council
approve a resolution of Negative Declaration for the need for an Environmental Impact
Statement for the Chanhassen High School Campus. Are we doing both right away tonight?
McDonald: Yes.
Undestad: And that the Planning Commission recommends the City Council approve an Interim
Use Permit to permit grading on the property in preparation of development, plans prepared by
Anderson-Johnson Associates dated 10-19-06, subject to conditions 1 through, what do we got?
25.
McDonald: Can I have a second?
Thomas: Second.
Undestad moved, Thomas seconded that the Planning Commission recommends that the
City Council approve a resolution of Negative Declaration of the Need for an
Environmental Impact Statement for the Chanhassen High School Campus. All voted in
favor, except Keefe who opposed, and the motion carried with a vote of 6 to 1.
Undestad moved, Thomas seconded that the Planning Commission recommends that the City
Council approve an Interim Use Permit to permit grading on the property in preparation of
development, plans prepared by Anderson-Johnson Associates, Inc., dated 10-19-06, subject
to the following conditions:
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Planning Commission Meeting - December 5, 2006
1.The 50-scale plans should be revised to clearly depict the wetland boundary and wetland
buffer areas.
2.Wetland buffer areas at least 16.5 feet in width should be preserved, surveyed and staked in
accordance with the City’s wetland ordinance prior to grading commencing. All wetlands and
wetland buffer areas should be protected by silt fence during grading.
3.The applicant should keep the goals set forth in the Bluff Creek Watershed Natural
Resources Management Plan (BCWNRMP) for the Lowlands Region in mind as a plan is
developed for the site and should work with staff to achieve these goals for this property.
The Primary Zone boundary and the 40-foot setback should be shown on the plans. No
grading is permitted within the first 20 feet of the 40-foot setback.
4.The erosion and sediment control plan should be aimed at minimizing the amount of exposed
soil at any given time and preventing erosion of exposed soil. Sediment control (especially
perimeter controls such as silt fence) should be viewed as a last resort. The applicant, the
contractor and all subcontractors should recognize that one silt fence at the bottom of a large
slope of exposed soil will not be sufficient to protect down gradient resources in even
moderate precipitation or snowmelt events. To decrease the potential for discharge of
sediment-laden water off-site, the applicant should prepare a plan for phasing the grading of
the project. In general, the areas within 200 feet of wetlands should be graded first and
permanently stabilized as soon as possible. Disturbed areas should be stabilized as soon as
possible after grading to minimize the total amount of exposed soil on site. New areas
should not be graded until after previously graded areas are stabilized.
5.Sediment & Erosion Control (SWPPP) Note 2.a.2 on Sheet C1.2 states that slopes steeper
than 6:1 should be “cat tracked.” The applicant should take extra measures to ensure that this
occurs because cat tracking has been shown to significantly decrease the potential for erosion
on long, steep slopes. A detail should be provided for cat tracking.
6.The haul route between the Construction Staging Area and the Temporary Stockpile Area
should be shown on the 50-scale plans.
7.All upland areas disturbed as a result of construction activities shall be immediately restored
with seed and disc-mulched, covered with a wood-fiber blanket or sodded within two weeks of
completion of grading in each disturbed area. If practical, a seed and blown-compost mix
should be considered in lieu of dormant seed and straw mulch. The plans should be revised to
call out erosion control blanket locations and to provide a detail for blanket installation.
8.Chanhassen Type II silt fence should be provided adjacent to all areas to be preserved as
buffer (both 16.5-foot wetland buffers and the 20-foot “no grading” zone around the Primary
Zone). The silt fence should be installed in overlapping “J-hooks” to break up the sections
and provide additional water and sediment retaining capacity. Orange tree protection fence
should be installed upslope from the Type 2 silt fence around the wetland between
Temporary Sediment Basin No. 3 and Temporary Sediment Basin No. 4 as added protection
so equipment operators do not impact the wetland by driving heavy equipment through it.
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Planning Commission Meeting - December 5, 2006
9.The plans should be revised to include Chanhassen’s standard details where available (e.g.,
Detail 5300 for silt fence; Detail 5301 for rock construction entrance). It appears that detail 3
on Sheet C1.4 is intended to depict the proposed checks within the temporary drainageways
shown on Sheet C1.2. This should be clarified and the checks should be installed as often as is
necessary to minimize the velocities of runoff in the drainageways. The plans should be revised
to show a minimum 75-foot long rock construction entrance.
10.In lieu of the proposed outlet pipes for the temporary sediment basins, temporary perforated
risers and stable emergency overflows (EOFs) are needed; details should be included in the
plan. The basins should be properly sized for the watershed areas, according to NPDES
requirements (i.e., the basins should provide storage below the outlet pipe for a calculated
volume of runoff from at least a 2-year, 24-hour storm from each acre drained to the basin,
except that in no case shall the basin provide less than 1800 cubic feet of storage below the
outlet pipe from each acre drained to the basin). The outlet pipes should discharge upstream
from the edge of the receiving wetlands and should be stabilized with riprap.
11.In the present design, water is routed into the wetland in the northeast corner of the site
instead of into Temporary Sediment Basin No. 4. The grading in this area of the site should
be revised to ensure that all discharge from disturbed areas is directed into either Temporary
Sediment Basin No. 3 or Temporary Sediment Basin No. 4 prior to discharge into the
wetland.
12.Street cleaning of soil tracked onto public streets shall include daily street scraping and street
sweeping as needed.
13.The applicant shall apply for and obtain permits from the appropriate regulatory agencies (e.g.,
Riley-Purgatory-Bluff Creek Watershed District, Minnesota Pollution Control Agency) and
comply with their conditions of approval.
14.All temporary stockpiles shall be temporary seeded and mulched within 7 or 14 days, in
accordance with the NPDES Phase II construction site permit.
15.Rock dissipation shall be installed at all pipe outlets within 24 hours of placement of the
outlet pipes.
16.Slope lengths greater than 75 feet shall be broken up with a minimum 12-foot wide bench
every 75 feet.
17.A minimum12-foot buffer area shall be maintained between the perimeter control and all
stockpiles to provide access around the stockpiles for maintenance purposes.
18.Dewatering activities shall only be allowed after consulting with the on-site city inspector of
the project to ensure compliance with the NPDES permit for dewatering activities.
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Planning Commission Meeting - December 5, 2006
19.Silt fence shall be placed parallel to contours. In locations where silt fence will cross
contours, J-hooks shall be installed at 75-foot intervals. Silt fence shall not be staked on site
by scaling off the proposed plan, but shall be staked by the survey crew taking shots in the
field. The applicant shall contact SWCD staff prior to silt fence installation so staking on site
can be reviewed to ensure compliance with this request.
20.Drainage swales and ditch cuts shall be employed during mass grading to maintain a positive
flow of stormwater to the temporary basins.
21.During final grading of the site, the height of the berm over the sanitary sewer shall be
reduced to the maximum extent practicable, otherwise additional drainage and utility
easements may be required.
22.The developer is required to televise the section of sanitary sewer over which grading
operations will occur before and after construction to determine if the site grading damaged
the pipe.
23.ISD 112 shall be responsible for repairing any sections of sanitary sewer damaged during
construction.
24.The developer must place sanitary sewer manhole sections on the existing manhole to bring
the top of manhole up to the existing grade.
25.No more than eight inches of rings is allowed on the sanitary sewer manhole.”
All voted in favor, except Keefe who opposed, and the motion carried with a vote of 6 to 1.
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