HomeMy WebLinkAboutFOSSIL CREEK ESTATES PUD PRELIMINARY - 50 92D - SUBMITTAL DOCUMENTS - ROUND 1 - WETLANDS DOCUMENTSTR Boss
ENVIRONMENTAL AND BIOLOGICAL CONSULTING
October 26, 1993
Mr. Tom Shoemaker
Director
City of Fort Collins Natural Resources Department
Fort Collins, CO 80522-0580
RE: Conceptual Wetlands Mitigation Plan for the Fossil Creek
Estates P.U.D.
Dear Mr. Shoemaker:
On behalf of Fossil Creek Estates (FCE) TR Boss Environmental and
Biological 'Engineering (TRB) is pleased to submit this conceptual
wetlands mitigation plan for the FCE P.U.D. for your review.
FCE understands that site plans and cross section plans of the
P.U.D. and wetland areas will have to be provided to the City of
Fort Collins and to the Army Corps of Engineers (COE)- before the
plan can be approved.
Presently FCE's siteplan shows the filling of 1.02 acres of
wetlands-. FCE has been advised that the final site plan must show
1.0 acre or less of filled wetlands to be considered for a COE
Nationwide 404 wetlands permit... It is TRBIs understanding that
FCE will be able to fill in less than 1.0 acre of wetlands in the
final P.U.D. site, plan. Once the final site plan has been approved
by FCE; the mitigation plan will be resubmitted to the City of Fort
Collins,. along with engineering specifications. The COE will also
receive the completii.mitigation package-, along with a request for
a Nationwide Permit'.
If you. have any questions. regarding. this conceptual mitigation plan
please call me at. (.303)..,223-5145.or (303): 223-50512.
inngerely,
Theodore R Boss, Ph..D
TR Boss Environmental and Biological.Consulting.
cc Carter Ewing - Fossil Creek Estates
Jim Sell -Jim Sell Design
308 MILKY WAY • FORT COLUNS, COLORADO 80525 (303) 223-5052 RESIDENCE • (303) 223-5145 OFFICE/FAx
B
CONCEPTUAL WETLANDS MITIGATION PLAN
FOSSIL CREEK ESTATES P.U.D.
FORT COLLINS, COLORADO .
T.R. BOSS ENVIRONMENTAL AND BIOLOGICAL.CONSULTING
OCTOBER, 1993
CONCEPTUAL WETLANDS MITIGATION PLAN
FOSSIL CREEK ESTATES P.U.D.
FORT COLLINS,. COLORADO
1.0 Mitigation Area
The proposed mitigation area is an upland area adjacent to wetlands
along Fossil Creek that forms the northern border of the Fossil
Creek Estates (FCE) P.U.D..
FCE would enlarge the existing wetlands along Fossil Creek at a 1:1
ratio to replace small wetlands areas (totalling 1.02 acres)
located in lots 2, 3, 10, ll, 12, 13, 17,.18', 24,- 26, 27, 28, 29
122, 123 (See Site Plan):.
2.0 Surveying
No excavation will be started untilthe mitigation site has been
surveyed and 'staked by the Contractor, and the Engineer has
obtained elevations and measurements of the -ground surface. The
information will. be utilized in the development of the final
grading plan. The grade of the mitigation site will be at the same
elevation as the existing Fossil. Creek wetlands.. .The Engineer will
.verify the Contractor's final grade, .following excavation.
The cross-sectioncoordinates of the mitigation site- will be
provided_ by: surveyors. hired_ by F.CE; and. will be surveyed into a
National Datum Survey Point, The"Grading Plan and- Grading Plan
cross -sections, along with -the sit"e plan, will be. submitted to, the,
City of Fort' Collins. with. the final mitigation plan.
3.O .Earthwork
This. -items covers ."clea.ring, excavation and grading, disposal,
placement;: aopsoiling and compaction of all materials within the
limits of ,.work required to, construct approximately 1.2 acres of
palustrine emergent wetlands.
3.1 vegetation Clearing
The initial step'in the implementation of. the -mitigation plan is
the clearing: .of the existing vegetation at the -mitigation site.
Cleared vegetation will be disposed of. at a.site designated by, the
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City of Fort Collins and/or Larimer County. The Contractor will
make all necessary arrangements for obtaining suitable disposal
locations. Vegetation debris will be disposed of in.a manner
acceptable to the Engineer. Burning will not be permitted without
prior approval by the City of Fort Collins and/or Larimer County.
Clearing will be performed in a careful and orderly manner, with
due consideration and protection of adjoining property and the
public. Those areas not to be cleared would be clearly staked, and
it would be the responsibility of the contractor to ensure such
areas would not be damaged during the wetland creation process.
3.2 Excavation and (trading
Subsequent to removal of vegetation, soils will be removed
according to the final grading plan. The contractor may need to
obtain a grading permit from_the.City of Fort Collins.
After the mitigat'on site has been cleared, the Contractor would
salvage the topsPil and temporarily stockpile it in an upland area.
While clearing the vegetation and excavating the topsoil (and
potentially subsoil) at the mitigation site all. work will be done
with equipment (within the upland. No machinery will be allowed to
excavate the mitigation site from the wetland side of the site. 4
toxic materials such as gasoline, cleaning fluids, oil, etc.t
be stored at least 200 feet from the mitigation site and the Fossil
Creek wetlands.
The vegetation and topsoil in the small wetland areas that will be
filled in for the development of the P.U.D. will also be salvaged
and stockpiled.
Suitable equipment necessary for proper. preparation and treatment
of the ground surface,, stripping of topsoil, and for the placing of
the topsoil will be. approved by the Engineer before the various
operations are started..
After the removal of the topsoil, the subsoil will be excavated to
final grade as shown' -in the engineering plans. The subsoil will
either be temporarily stored.in an -upland area before being hauled
and disposed of at an offsite location, or it may be used as fill
in .the P.U:D:_, if its physical properties are appropriate as
construction...materials.
2.3 Topsoiling.
Once the mitigation site has been excavated to final grade, the
vegetation and topsoil from the wetlands that will be lost for the
construction of the P.U.D. will be applied to the mitigation site.
Immediately prior to.applying the vegetation and topsoil, the
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surface of the mitigation site substrate may be loosened by disc or
spike -toothed harrows, or by other means approved by the Engineer,
to a minimum of 6 inches, to facilitate bonding of the topsoil to
the covered subsoil.
The topsoil from the. mitigation site will be used in the
construction areas where wetlands will be lost.
2.4 compaction
The mitigation site will not be compacted after the topsoil is
replaced.
2.5 Restoration and.cleanup
At all times of construction, the Contractor will maintain the
mitigation site; material stockpiles, and adjacent areas. in a
reasonable state of order -and cleanliness.
Before final acceptance, the mitigation site, material sites, and
the ground occupied by the Contractor in connection with the work.
will be cleared of all rubbish, excess materials, equipment, and
all parts of the work will be left in a condition acceptable to the
appointed Engineer.
3.0 soil Erosion and sediment Control
Soil erosion measures will be ordered by the Engineer during the
life of the project: The -work will -be,tailored:.to address site
specific grading; schemes Prior to the start of construction of
the mitigation site the Contractor- will submit schedules, for
accomplishment of temporary and permanent erosion: control work as
are applicable for clearing, and grading. Work will notbe started
until the erosion control schedules and methods of operationfor
the. applicable -construction have been accepted by the, Engineer. The
Engineer' will have..'the authority to direct the Contractor to
immediately.. provide_.permanent or temporary control. measures to
minimize_po.11ution to.°Waters of.the United States"'.
Should erosion -and pollution control conditions develop, temporary
measures w]:f,be,-used to correct conditions that were not foreseen
during the'design:phase of, the mitigation site:
In the -event that temporary. -"erosion and -pollution control measures
are required, due to the Contractor's negligence,- carelessness, or
failure to. -install permanent controls as. part`. of the work as
scheduled, -or, as -ordered by the Engineer, such- work will be
performed at the expense.of the Contractor...
The erosion control features installed by the Contractor will be
maintained by the Contractor during the construction period.
Temporary erosion and sedimentation control measures will be
implemented prior to excavation activities and will continue
throughout the establishment period of the created wetland.
4.0 Planting Activities
It is recommended that there will be no formal planting of
palustrine emergent wetland plant species at the mitigation site.
The vegetation ad topsoil excavated from the small wetland areas
within the P.U.D. contain wetland seed banks. Also the mitigation
site will be located adjacent to an existing emergent wetland.
Both the seed bank and the adjacent wetland propagule source will
establish an emergent, wetland within the mitigation site within 1
to 2 years.
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