HomeMy WebLinkAboutSDP200800144 Review Comments Final Site Plan and Comps. 2009-01-15ALg�,��
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COUNTY OF ALBEMARLE
Department of Community Development
401 McIntire Road
Charlottesville, Virginia 22902 -4596
Phone (434) 296 -5832 Fax (434) 972 -4126
Project: SDP - 2008 - 00144, Crown Automotive Site Plan
WPO- 2008 - 00093, Crown Automotive SWM and ESC Plans
Plan preparer: Ankita Kot; Freeland and Kauffman, Inc.
Owner or rep.: Crown Motorcar Company, LLC c/o Asbury Automotive Group, Inc.
Date received: 24 September 2008 (plan signed date 10 September 2008)
(Rev. 1) 20 November 2008 (plan signed 19 November 2008)
Date of Comment: 31 October 2008
(Rev. 1) 15 January 2009
Engineer: Phil Custer
The Final Site, SWM, and ESC plans for Crown Automotive, officially received on 11 December 2008
because of a late payment of the WPO plan, have been reviewed. The plans cannot be approved as
submitted and will require the following changes /corrections prior to final approval.
A. General review comments:
1. A boundary line adjustment appears to be necessary so that the building is only located on one
property. If the property boundary is not adjusted, the County Building Official may require a
firewall in the building between the two parcels.
(Rev. 1) Comment has been addressed. Engineering comments on the plat will be given in
a separate letter.
2. An easement plat showing the required access, drainage, swm, private sanitary on the ACSA
property, and parking easements must be recorded prior to site plan approval.
(Rev. 1) The easement plat has been received and comments will be given in another letter.
3. Please note on all sheets and documents that the public road west of the site has been called
People's Place rather than Pantops Park Drive.
(Rev. 1) Comment has been addressed.
4. VDOT approval is required. At this time, VDOT comments have been forwarded to the
applicant. The applicant should work directly with VDOT regarding these comments.
(Rev. 1) Comment has been addressed.
B. Site Plan review comments:
make sure the date and source of the topography is listed on Sheet C2. [DM]
(Rev. 1) Comment has been addressed.
2. Please show all existing easements with deed book references, locations, and dimensions on
the properties involved.
(Rev. 1) Comment has been addressed.
3. Please shade all critical slopes on Sheet C2. [DM]
(Rev. 1) The shading of the critical slopes did not duplicate well on sheet C2. Also, it
appears that not all the critical slopes have been shaded.
4. All slopes steeper than 3:1 will require a low maintenance, non - grassed groundcover. [DM]
(Rev. 1) Comment has been addressed.
5. The guardrails required at the top of the retaining walls must be a VDOT Standard. The site
plan must also specify the proper guardrail terminals as well.
(Rev. 1) Please call out the VDOT standard on sheet C10 and the wall details.
6. A guardrail is needed in the southwest corner of TMP 78 -15. It appears that because of the
required distance the guardrail must be spaced from the face of the retaining wall, the wall will
need to be moved into the adjacent property and the easement will need to be larger.
Engineering review recommends working with TMP 78 -15C to eliminate the need for the 30ft
retaining walls by filling to meet grade.
(Rev. 1) Comment has not been addressed. The dimensions of the walls drawn on the plan
do not appear to match the detail on sheet RW5. The face of the top of the wall should
measure as 5ft from the face of curb and it many cases it does not. Also, the widths of the
walls due to its slope are not drawn accurately. Engineering review is particularly
concerned with Wall B because of its considerable height.
7. A guardrail is also needed over the tiered retaining wall west of the building.
(Rev. 1) Comment has been addressed.
8. There cannot be a break at the guardrail at the filterra. The wall must be pushed into the
adjacent property. Engineering review recommends working with TMP 78 -15C to eliminate
the need for the retaining wall in this area.
(Rev. 1) Comment has been addressed.
9. Retaining walls B, C, E, and G should have both a guardrail and a taller safety /pedestrian
railing like the detail on Sheet RW5.
(Rev. 1) Comment has been addressed.
10. In many places, it does not appear there is enough room for a few of the walls and guardrails
considering the loss of 7.1 degree stacking angle of some of the walls. At 7.1 degrees, you
lose lft horizontal for every 8ft of wall height. For instance, at retaining wall C, the distance
between back of curb of the travelway and back of curb of the lot on sales office property is
4.5 ft. Considering the loss of lft because of the slope of the wall, the 3.3ft between the face
of wall and the back of the guardrail, and the 1.5ft width of the guardrail (total 5.8ft), there is
not enough room.
(Rev. 1) Comment has not been addressed. The dimensions of the walls drawn on the plan
do not appear to match the detail on sheet RW5. The face of the top of the wall should
measure as 5ft from the face of curb and it many cases it does not. Also, the widths of the
walls due to its slope are not drawn accurately. Engineering review is particularly
concerned with Wall B because of its considerable height.
11. A private sanitary sewer easement is needed over the sewer lateral through TMP 78 -15B.
Also, a new drainage easement for pipe from the ACSA property to TMP 78 -15B will be
needed. A plat showing all of these easements (plus the existing and already proposed
easements in this set) must be recorded prior to site plan approval.
(Rev. 1) Sanitary easement on TMP 78 -15B no longer needed because of the pending
boundary line adjustment on the easement plat. The private sewer easement through the
ACSA parcel to the main line will be reviewed under the subdivision plat (SUB -2008-
00286).
12. Please show drainage easements on the Landscape plan. No trees of significant size will be
allowed inside the drainage easements.
(Rev. 1) Comment has been addressed.
13. All entrances must have a VDOT designation. [DM]
(Rev. 1) The southern entrance should have a VDOT entrance called out as well.
14. All entrances must not exceed 4% for the first 40ft from the curbline of Route 250. [DM]
(Rev. 1) Comment has been addressed.
15. Please label all curbing with the proper VDOT designation. [DM]
(Rev. 1) Comment has been addressed.
16. There does not appear to be a loading space that meets 18- 4.12.18 provided on site. A waiver
from the Zoning Department will be required if one is not provided.
(Rev. 1) The response from the Zoning Administrator regarding the request for a waiver
will be forwarded to the applicant when it is received by engineering.
17. Please provide an island at the southwest corner of the new building that is at least 3ft wide.
(Rev. 1) Comment has been addressed.
18. An inlet should be provided east of the site entrance along Route 250. As currently designed,
close to 250 linear feet of 3.5 lanes will drain across the entrance and flow into inlet 4. Curb
inlet calculations should be provided for this new inlet and storm pipe. A drainage easement
will be required on this system of pipe.
(Rev. 1) The curb inlet calculations indicate that this inlet is located in a sump when it is
actually on grade. Please adjust the inlet calculations. A larger throat on the inlet should
also be provided to increase the efficiency of the structure.
19. All changes of direction in stormpipe systems must be at least 90 degrees.
(Rev. 1) Comment has been addressed.
20. Please provide traffic generation and distribution summarys.
(Rev. 1) Comment has been addressed.
21. Please use VDOT specifications in the parking lot pavement section.
(Rev. 1) Comment has been addressed.
22. Please correct the sidewalk detail. The sidewalk detail should not show a 6" curb unless it
meets a VDOT CG designation. The sidewalk detail must also show in section 4" of stone
base and 4" of concrete of 3000psi strength at 28 days or stronger that is reinforced with a
wire grid. Handicap ramps should be specified with a VDOT standard.
(Rev. 1) Comment has not been addressed. The sidewalk detail should not show a 6" curb
unless it meets a VDOT CG standard.
23. A dumpster pad detail meeting the requirements listed in the design manual is required.
(Rev. 1) Comment has been addressed.
24. The dumpster pad must be at least 18ft long.
(Rev. 1) Comment has been addressed.
25. Please provide more spot elevations in the area of the dumpster to assure that drainage does
drain across the footprint of the dumpster.
(Rev. 1) Comment has not been addressed.
26. Please provide details for pipe systems running underneath a retaining wall. Pipes 11 -10, 15-
13, and 2 -1 will likely be close to the foundation slab of the proposed retaining walls.
(Rev. 1) Comment has not been addressed. The walls above the pipes from 12 -11 and 11 -10
are not represented accurately on the drainage profile sheet. For instance, according to the
wall detail on RW3, the base of wall A is at 360.5' which conflicts with the top of both
pipes. A detail will be needed for both of these pipes.
27. The set appears to be missing several storm drain profiles. The following profiles should be
included in the set: RI -9, 15 -14, 18 -13, 12 -11, and 19 -9.
(Rev. 1) Comment has been addressed.
28. The following information needs to be shown in the drainage profiles:
a. A VDOT designation for each structure.
(Rev. 1) Comment has been addressed.
b. The throat length for each curb inlet.
(Rev. 1) Comment has been addressed.
c. The grate type for each grate inlet.
(Rev. 1) Comment has been addressed.
d. Structures will a vertical drop of 4ft or greater (including from the surface to the bottom of
the facility) must have VDOT Standard IS -1 specified.
(Rev. 1) IS -1 is not required on the inlets with a 2ft riprap sump since they serve the same
purpose. Please remove one of the call outs in structure 2 and 7. Engineering review
recommends the use of IS -1 instead of the riprap scour protection so that there is not
permanent pool of water in the structure. Please note that it appears as though the
applicant is proposing a sump in inlet 7 which would require the replacement of the entire
structure (though it might need to be replaced anyway). If that is the case, the structure
should be shown as new in the profile.
e. All structures deeper than 12ft must have a VDOT Standard SL -1 (including existing
structure 7).
(Rev. 1) Comment has been addressed.
29. The drainage computations show that several of the proposed 36" pipes are undersized. Please
correct.
(Rev. 1) Calculations could not be confirmed because a drainage area map for the
upstream system was not provided.
30. Drainage maps should be provided for the existing storm sewer main to estimate the flow
through the site. Currently, the drainage area map only shows the area draining to the new
proposed inlets. For instance, drainage area lines estimating the watershed for pipe system 19-
9 to determine the flow through pipe 9 -7.
(Rev. 1) Calculations could not be confirmed because a drainage area map for the
upstream system was not provided.
31. In the drainage area maps, please include a hydrologic coefficient and a time of concentration
for each drainage area.
(Rev. 1) Comment has been addressed.
32. Will there be any grading from the base of the tiered walls to Peoples Place? Please provide
spot elevations at the base of the walls in this area. Has inlet 22 been placed at its current
location to catch runoff from the swale on the east side of Peoples Place?
(Rev. 1) Comment has been addressed.
33. Please specify a 2% cross slope on the travelway from the building down to Filterra 2.
(Rev. 1) Comment has been addressed.
C. SWM review comments:
1. SWM facility maintenance agreements will need to be recorded for both properties before the
site plan can be approved. Please submit these documents with fees directly to Pam Shifflett
after consulting the guidelines available on the county website.
(Rev. 1) The agreement has been received and its approval is pending.
2. Please provide approval letters from the manufacturers of the prefabricated stormwater
systems ( Filterra and Contech) stating that as proposed, the facilities meet the minimum
standards and removal rates attributed to them by the Virginia DCR.
(Rev. 1) Comment has been addressed.
3. The output from the routing of the detention facility does not appear to meet the full
requirements of the design manual and state law in the cases when downstream channels are
inadequate. However, engineering review realizes that meeting those requirements with such
a small site is practically impossible and will grant a variation from the requirements.
Detention and satisfying the downstream channel limitations concerns will be approvable if
both the 2 and the 10 year storms are routed through only 3" orifice. The applicant may use
either the modified rational method (routing the critical storm) or the SCS method for the
facility. Please contact me to discuss this further.
(Rev. 1) Comment has been addressed.
4. In the post - development drainage area map for the detention facility, please provide the
acreage, hydrologic coefficient, and time of concentration. The acreage appears to be less than
the 2.8 acres that has been used in the routing calculations.
(Rev. 1) Comment has been addressed.
5. The post - development drainage area map is not correct. The drainage area line as drawn on
Sheet C20 appears to still be the limits of disturbance for the project rather than the drainage
area to the detention facility. For instance the drainage area to the facility should be extended
to the centerline of Route 250. Also, inlets 18 and 20 do not drain to the detention facility as
indicated in the map.
(Rev. 1) Comment has been addressed.
6. Engineering review has a few concerns regarding the Stormfilter systems:
a. As currently shown, both inlet pipes will be filled with water. Please place the inlet pipes
above the water elevation so that the upstream storm pipes are empty under normal
conditions.
(Rev. 1) Comment has not been addressed.
b. The 4" orifices in the concrete boxes limit will cause storms of a high intensity to bypass
the treatment facility. The current setup does not appear to match the detail approved by
DCR in the VSMH. I am concerned a large percentage of the first flush will not be treated
with the two facilities as proposed. By my calculations, any storm that is more intense
than 0.33 in/hr will use the bypass.
(Rev. 1) Comment has been addressed.
7. Inlet 20 should drain to the detention facility and should be treated. A drainage easement will
be required on this pipe system.
(Rev. 1) Comment has been addressed. Comments on the easement plat will be given in a
separate letter.
8. The Stormfilter catch basins should be sized to treat the water quality volume for the drainage
area to them.
(Rev. 1) Comment has been addressed.
9. The SWM facility easement will need to be recorded on TMP 78 -15B before the site plan can
be approved.
(Rev. 1) SWM easement is no longer needed because of the pending boundary line
adjustment.
10. Access should be provided in the detention facility to all inlet and outlet points.
(Rev. 1) Comment has been addressed.
11. A trashrack is required on all orifices.
(Rev. 1) Comment has been addressed.
12. Please provide a note on the plan that all manhole access to the detention facility must meet all
OSHA standards.
(Rev. 1) Comment has been addressed.
13. The equivalent of the VDOT Standard SL -1 should be provided for in the details for this
detention structure.
(Rev. 1) I do not see where this has been provided.
14. All pipes entering or leaving the facility must be a minimum 15" in diameter.
(Rev. 1) Comment has been addressed.
15. The topography in the parking lot uphill of Filterra 3 creates a channel that appears to bypass
the filterra. Please correct.
(Rev. 1) Comment has not been addressed.
16. The SWM portion of the WPO bond will be computed once the plan has been approved.
(Rev. 1) Please provide cost estimates from the suppliers of all pre fabricated SWM systems
so that they can be bonded. The estimates should also include a reasonable cost for
installation as well.
17. Additional comments may be required based on the changes to the plan.
(Rev. I) No new comments are expected.
D. Site ESC review comments:
1. There appear to be conceptual problems with the erosion and sediment control plan and a full
review could not be completed. There are considerable issues when the site transitions from
Phase II to Phase III with the current plan. Engineering review recommends building a
sediment basin, using structure 7 as the riser, immediately after the stormsewer main (11 -10 -9-
7) is constructed and directing all water during construction to it. This way, the ESC measure
is in the corner of the site and can be removed and filled once the rest of the site is deemed
adequately stabilized by the site inspector.
(Rev. 1) In phase I of the ESC plan, please note in the construction sequence that structure
7 needs to be retrofitted to be the sediment basin riser.
2. A construction e ice is needed for each phase of the ESC plan.
(Rev. 1) Comment has been addressed.
3. The construction entrance must be placed in a location that does not require any initial
grading. The location proposed in phase I and lI requires grading. Engineering review
recommends using the existing entrance (across from the entrance to Peoples Place) during the
initial phases of construction.
(Rev. 1) Comment has been addressed.
4. Pipe outlet sediment traps require a variance from the program authority. Please provide a
letter justifying the use of this facility if you continue to use it in place of a standard in the
VESCH and a fee for a variance request of $760.
(Rev. 1) Comment not longer needed.
5. Please label the critical slopes on the phase I plan.
(Rev. 1) Comment has been addressed.
6. Please provide dust control on site.
(Rev. 1) Comment has been addressed.
7. Please provide a parking and staging area for each phase of construction.
(Rev. 1) Comment has been addressed.
8. Please provide a location for a soil stockpile for each phase of construction.
(Rev. 1) Comment has been addressed.
9. This site will require significant amounts of soil in order to construct. Please specify the
borrow site so we can confirm the site has an adequate erosion control plan. Please include
this in the Offsite areas of the ESC Narrative.
(Rev. 1) Comment has been addressed.
10. The silt fence on the west end of the site will not filter water but will act more as a diversion
dike. Please replace this silt fence dike (or using the existing swale) to direct sediment -laden
water to the sediment basin facility until the site is to grade. (Please see comment D.1).
(Rev. 1) The storm pipe 21 -7 should not be constructed in Phase II but Phase III. The
existing Swale should be diverted into the basin as long as the basin is active. Please label
the existing swale as a DV and provide a diversion dike near the basin, if necessary, making
it clear that runoff draining west from the site should be directed into the sediment basin.
11. Please make the following changes in the ESC narrative:
c. A title is needed.
d. Please identify all steep slopes on the Crown parcel and the adjacent slopes on the ACSA
property as critical areas.
e. The please remove the reference to Flat Branch and Bull Run from the narrative. Those
water bodies do not exist in Albemarle County.
(Rev. 1) Comment has been addressed.
12. Inlet protection is needed on the existing inlets in the parking lot of the existing sales property.
(Rev. 1) Comment has been addressed.
13. Please remove the existing entrance from People Place in Phase III of the plan.
(Rev. 1) Comment has been addressed.
14. The ESC portion of the WPO bond will be calculated once the plans are ready to be approved.
(Rev. 1) Comment remains unchanged.
15. Additional comments may be required based upon the required changes.
a. (Rev. 1) Please provide a safety fence around the sediment basin with a sign stating
"Danger, quick sand, do not enter." A safety fence should also be placed around the
entire site, especially areas near the existing crown building and parking lot.
b. (Rev. 1) Please clarify when and how the new entrance is to be constructed and the old
entrance closed.
c. (Rev. 1) The construction sequence mentions that the outlet pipes of the water quality
features are to be blocked during construction. Shouldn't the inlet pipes and surfaces
be blocked until the site is stabilized? Will sediment -laden water be sent through the
detention facility of will the inlets upstream be sealed until site stabilization has
occurred?
d. (Rev. I) Please provide a note in the Phase III construction sequence that the detention
facility is to be cleaned out once the site is stabilized to the satisfaction of the Erosion
and Sediment Control Inspector.
Please contact me at (434) 296 -5832 ext. 3072 or email pcuster @albemarle.org if you have any questions.
File: E2_fsp esc swm_PBC_Crown Automotive.doc