HomeMy WebLinkAboutCorrespondenceDave Argo
From: Dave Argo
Sent: Wednesday, August 21, 2019 8:14 AM
To: 'Chris Jung'
Cc: Glenn Hartmann; Andy Schwaller (aschwaller@garfield-county.com)
Subject: Midland Exemption, Parcel C - Buildings Q and V
Chris:
We have begun review of a building permit application for two new warehouse buildings (buildings "Q" and "V") to be located
at 62 County Road 113 (aka: Midland Exemption, Parcel C). Unfortunately, there are a number of issues which must be
addressed before we can move forward with finalizing our plan review and issuing a building permit for either of these
proposed buildings.
Most importantly, this parcel is zoned "Rural" and Warehouse occupancy/use is not a use by right within the Rural zone
district, meaning that a Land Use Change Permit (LUCP) will need to be applied for and obtained through our Planning
Department before we can finalize our review and issue building permits. I suggest that you discuss this process with Glenn
Hartmann, our Principal Planner, who is familiar with this project and can better describe to you what all is involved and
required to obtain the LUCP.
In addition to obtaining the LUCP, there are several other items that we noticed in our preliminary review, and you should also
work to clarify or address these items so that we can move forward once the LUCP process has been completed. These items
include the following:
A. Soils Report — The soils report included in your application (and referenced on the Structural Engineer's plans) are for
the wrong project location. Instead, this soils report was performed on Parcel B of the Midland Exemption (across the
street north from the actual project site). Please provide us with the correct soils report for the location of Buildings
"Q" and "V". You can quickly see the difference when comparing the site plan provided by Zancanella vs. building
footprints illustrated in HP-Kumar's report. Once the correct soils report is in hand, it also must be provided to the
Structural Engineer to determine if any substantive changes are required to his plans as a result of this mix-up.
B. Engineered Site Grading & Drainage Plan — The site plan prepared by Zancanella is inadequate in terms of addressing
site grading, drainage, erosion and impact of the steep slopes rising to the east above the proposed buildings.
Although it serves as a general layout plan, it does not address certain key issues. For example, drainage on the uphill
slopes are shown to simply drain directly into the backside of these buildings without a properly designed drainage
swale to deter run-off. Not only does this approach not conform to good geotechnical engineering practice, it also
does not comply with the Building Code. In addition, there needs to be a larger scale site plan for each of these
buildings indicating site drainage and actual height of retainage portion of the foundation walls so that the Structural
Engineer can coordinate with his work. We require that you submit
to our office a properly Engineered Site Grading & Drainage Plan as prepared by a Colorado licensed Professional
Engineer who is more familiar and experienced with these issues. The amended Engineered site grading and drainage
plan will need to address run-off at the uphill side of the buildings, as well as demonstrating compliance with the
following sections of Garfield County's Land Use & Development Code:
• 1 Section 7-204: Drainage & Erosion
• Section 7-207: Natural & Geologic Hazards for slopes > 30%
Thank you for your prompt attention to addressing these outstanding items, none of which is more important than following
up with Glenn Hartmann to discuss the LUCP which is required to allow the "Warehouse" occupancy/use within the Rural
zone district. While you are working through these issues, we will place these 2 projects in our "pending" file until we receive
updated plans and confirmation from the Planning Dept. that the LUCP is in place.
Dave Argo
Plans Examiner
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c. Channels downstream from the stormwater detention pond
discharge shall be protected from increased channel scour, bank
instability, and erosion and sedimentation from the 25-year return
frequency, 24-hour design storm.
d. Removal of pollutants shall be accomplished by sizing dry
detention basins to incorporate a 40-hour emptying time for a
design precipitation event of 0.5 inches in 24 hours, with no more
than 50% of the water being released in 12 hours. If retention
ponds are used, a 24-hour emptying time is required. For
drainage from Parking Lots, vehicle maintenance facilities, or
other areas with extensive vehicular use, a sand and oil grease
trap or similar measures also may be required. To promote
pollutant removal, detention basins length -to -width ratio should be
not less than 2, with a ratio of 4 recommended where site
constraints allow. A sedimentation "forebay" is recommended to
promote long-term functioning of the structure. Access to both the
forebay and pond by maintenance equipment is required.
e. Culverts, drainage pipes, and bridges shall be designed and
constructed in compliance with AASHTO recommendations for a
water live load.
7-205. ENVIRONMENTAL QUALITY.
A. Air Quality.
Any Land Use Change shall not cause air quality to be reduced below acceptable levels
established by the Colorado Air Pollution Control Division.
B. Water Quality.
At a minimum, all hazardous materials shall be stored and used in compliance with
applicable State and Federal hazardous materials regulations.
7-206. WILDFIRE HAZARDS.
The following standards apply to areas subject to wildfire hazards as identified on the County
Wildfire Susceptibility Index Map as indicated in the County's Community Wildfire Protection
Plan.
A. Location Restrictions.
Development associated with the land use change shall not be located in any area
designated as a severe wildfire Hazard Area with Slopes greater than 30% or within a
fire chimney as identified by the Colorado State Forest Service.
B. Development Does Not Increase Potential Hazard.
The proposed Land Use Change shall be developed in a manner that does not increase
the potential intensity or duration of a wildfire, or adversely affect wildfire behavior or fuel
composition.
C. Roof Materials and Design.
Roof materials shall be made of noncombustible materials or other materials as
recommended by the local fire agency.
7-207. NATURAL AND GEOLOGIC HAZARDS.
A. Utilities.
Above -ground utility facilities located in Hazard Areas shall be protected by barriers or
diversion techniques approved by a qualified professional engineer. The determination
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a. Stabilizing rocks by bolting, gunite application (cementing),
removal of unstable rocks (scaling), cribbing, or installation of
retaining walls.
b. Slowing or diverting moving rocks with rock fences, screening,
channeling, damming, or constructing concrete barriers or covered
galleries.
c. Installation of structural barriers around vulnerable structures to
prevent rock impact.
2. The following development activities shall be prohibited in rockfall Hazard
Areas:
a. Activities that add water or weight to, or otherwise decrease the
stability of, cliffs or overhanging strata.
b. Activities that will reduce stability, including activities that remove
vegetation or other natural support material, or that require
excavation, or cause erosion that will remove underlying support
to a rockfall Hazard Area.
E. Development in Alluvial Fan Hazard Area.
Development shall only be permitted to occur in an alluvial fan if the Applicant
demonstrates that the development cannot avoid such areas, and the development
complies with the following minimum requirements and standards, as certified by a
qualified professional engineer, or qualified professional geologist, and as approved by
the County:
1. Development shall be protected using structures or other measures on
the uphill side that channel, dam, or divert the potential mud or debris
flow.
2. Disturbance shall be prohibited in the drainage basin above an alluvial
fan, unless an evaluation of the effect on Runoff and stability of the fan
and on the ground water recharge area shows that disturbance is not
substantial or can be successfully mitigated.
F. Slope Development.
Development on Slopes 20% or greater shall only be permitted to occur if the Applicant
demonstrates that the development complies with the following minimum requirements
and standards, as certified by a qualified professional engineer, or qualified professional
geologist, and as approved by the County:
Building Tots with 20% or greater Slope shall require a special engineering
study to establish the feasibility of development proposed for the site.
The study shall address feasibility of construction required for the use and
describe the mitigation measures to be used to overcome excessive
Slope problems.
Development shall be permitted to occur on Slopes greater than 30% only
if the Applicant demonstrates that the development cannot avoid such
areas and the development complies with the following minimum
requirements:
a. Cutting, filling, and other Grading activities shall be confined to the
minimum area necessary for construction.
b. Development shall be located and designed to follow natural
grade, rather than adjusting the site to fit the structure. Roads and
driveways built to serve the development shall follow the contours
7-14
of the natural terrain and, if feasible, shall be located behind
existing Iandforms.
Development on Unstable or Potentially Unstable Slopes. If a site is
identified as having moderate or extremely unstable Slopes, then
development shall be permitted only if the Applicant demonstrates that
the development cannot avoid such areas and the development complies
with certified geotechnical design and construction stabilization and
maintenance measures.
a. Cutting into the Slope is prohibited without provision of adequate
mechanical support.
b. Adding water or weight to the top of the Slope, or along the length
of the Slope, is prohibited.
c. Vegetation shall not be removed from the Slope unless the
integrity of the Slope can be adequately maintained.
4. Development on Talus Slopes. Development shall be permitted to occur
on a Talus Slope only if the Applicant demonstrates that the development
cannot avoid such areas, and the development complies with the
following minimum requirements and standards, as certified by a qualified
professional engineer, or a qualified professional geologist, and as
approved by the County:
a. The development shall be designed to withstand down Slope
movement.
b. The design shall include buried foundations and utilities below the
active Talus Slope surface.
c. Site disturbance shall be minimized to avoid inducing slope
instability.
d. The toe of a Talus Slope shall not be removed unless adequate
mechanical support is provided.
G. Development on Corrosive or Expansive Soils and Rock.
Development in areas with corrosive or expansive soils and rock shall be designed
based upon an evaluation of the development's effect on Slope stability and shrink -swell
characteristics. Development shall be permitted only if the Applicant demonstrates that
the development cannot avoid such areas and the development complies with design,
construction stabilization, and maintenance measures certified by a qualified
professional engineer, or qualified professional geologist, and is approved by tile —
County.
Surface drainage shall be directed away from foundations.
Runoff from impervious surfaces shall be directed into natural drainages
or otherwise on -site in a manner that does not create or increase adverse
impacts to the development site or to adjacent or other property.
H. Development in Mudflow Areas.
Development shall be permitted in a mudflow area only if the Applicant demonstrates
that the development cannot avoid such areas, and the development adequately
employs, construction stabilization, and mitigation and maintenance measures as
designed by a qualified professional engineer, or qualified professional geologist, and as
approved by the County.
7-15
Dave Argo
From: Tim Beck <tbeck@za-engineering.com>
Sent: Thursday, September 26, 2019 3:38 PM
To: Dave Argo
Cc: 'Chris Jung'
Subject: [External] Cattle Creek Center - Southwest Bench
Attachments: Bldg Q grading contours.pdf; Sheet S3.1 annotated.pdf; basins (2).pdf
Follow Up Flag: Follow up
Flag Status: Flagged
Dave,
I am following up on a phone message I left last week for you regarding getting together and discussing the grading plan
for the southwest buildings.
I have reviewed the referenced county regulations and the proposed construction. Per Chris Jung, it appears that you
are concerned about the grading around the proposed Building Q. I have attached a portion of the plan which includes
existing and proposed contours to help visualize what we are proposing. I also have the following comments:
1. The drainage basins above the proposed building are very small, all less than an acre. The basin above
Building Q is not even half again larger than the roof of the building.
2. The height of fill behind the building is based on the typical structural section shown on plan sheet which
allows for a backfill height of 7' 8" above the finish floor elevation.
3. The builder is also the long term owner and has been in the construction business in this area for nearly 40
years. They are familiar with construction and construction in this area in particular.
Please give me a call to arrange a meeting so I can better address your concerns.
77;ff &el
Timothy P. Beck, P.E.
theck@za-engineering.com
Direct: 970.928.3422 I Office: 970.945.5700
Zancanella & Associates Inc. 1 Engineering Consultants
1011 Grand Avenue I Glenwood Springs, CO 81601
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