HomeMy WebLinkAboutWPO201800016 Correspondence 2018-06-28
CIVIL ENGINEERING | ENVIRONMENTAL | SURVEYING | GIS | LANDSCAPE ARCHITECTURE | CONSTRUCTION SERVICES
608 Preston Avenue
Suite 200
Charlottesville, VA 22903
P 434.295.5624
F 434.295.8317
www.timmons.com
June 27, 2018
Albemarle County
Dept. of Community Development
401 McIntire Rd, Rm 227
Charlottesville, VA 22902
RE: Birdwood Golf Course – VSMP Permit Plan Review – WPO201800016 - Comment
Response Letter
We have reviewed all of your comments from Rev 1 May 11, 2018 and made the necessary
revisions. The comments and plan edits have been coordinated with the County through a
series of meetings to discuss the revisions to the stormwater management and BMP strategies.
Please find our responses to the comments below in bold lettering.
A. Stormwater Pollution Prevention Plan (SWPPP)
The SWPPP content requirements can be found in County Code section 17-405. A
SWPPP must contain (1) a PPP, (2) an ESCP, (3) a SWMP, and (4) any TMDL measures
necessary.
1. The SWPPP was not found with this submittal . Design consultant is to
provide a SWPPP using the standard template from the county website.
The SWPPP has been provided with this submission.
Revision 1 Response: The SWPPP has been provided with this submission.
Revision 1 Comments:
1. Please add WPO 201800016 to the cover sheet of the SWPPP, plans and
stormwater management calculations.
WPO201800016 has been added to the cover of the SWPPP, plans
and calculations.
2. SWPPP Section 1 – Please provide a registration statement that is completed
to include the certification. Please delete instructions for completing in the
registration statement.
We are awaiting the signed registration statement from the
contractor. A revised SWPPP will be provided under a separate cover
once we receive it.
3. SWPPP Section 2 – Please provide a copy of the DEQ coverage letter when
obtained.
DEQ coverage letter will be added to the SWPPP when it is received.
4. SWPPP Section 4 – Please provide an 11”x17” copy of the latest E&SC plans.
ESC plans have been updated to include the most current submissi on.
It is also acknowledged that approved plans will need to be added
after plan approval.
5. SWPPP Section 5 – Please provide an 11”x17” copy of the latest SWM Plans.
SWM plans have been updated to include the most current
submission. It is also acknowledged that approved plans will need to
be added after plan approval.
6. SWPPP Section 7 – Impaired water status cannot be verified as registration
statement has not been completed.
Registration statement has been completed.
7. SWPPP Section 8 – Please provide name of qualified person and requested
information.
We are awaiting this to receive this information from the contractor.
A revised SWPPP will be provided under a separate cover once we
receive it.
8. SWPPP Section 9 – Please complete and sign the certification.
We are awaiting this to receive this information from the contractor.
A revised SWPPP will be provided under a separate cover once we
receive it.
9. SWPPP Section 10 – Per 9VAC25-880-70 Part K, please provide the person
with the authority to sign inspection reports or to modify the stormwater
pollution prevention plan.
We are awaiting this to receive this information from the contractor.
A revised SWPPP will be provided under a separate cover once we
receive it.
10. Please note that additional comments may be generated based on responses
to these comments.
Acknowledged.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. The PPP exhibit will need to be included in the SWPPP. Design consultant is
to provide a PPP exhibit using the standard template from the County
website.
The SWPPP has been provided with this submission.
Revision 1 Response: The SWPPP has been provided with this submission.
Revision 1 Comments:
1. SWPPP Section 6 – Per Albemarle County Code 17-404, the location of the
PPP activity/protection is to be graphically/clearly marked on the PPP.
PPP has been updated.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or
disapprove a SWMP. This plan is disapproved, and the reasons are prov ided in the
comments below. The stormwater management plan content requirements can be
found in County Code section 17-403.
1. The plan notes that this project constitutes redevelopment (development on
prior developed land) of the 276.8-acre disturbed area, and thus the total
phosphorous load is to be reduced to below the pre-development total
phosphorous load by 20%. The plan proposes to utilize Virginia DEQ
Stormwater Design Specification No. 6 Rainwater Harvesting as the means to
reduce the total phosphorous load as required. The plan proposes to use the
existing pond #3 as the “storage tank/cistern,” approximately 96 acres of golf
course-managed turf as the “rooftop,” and irrigation of approximately 60
acres of golf course-managed turf over an 8-9-month period (seasonal
outdoor use) as the “non-potable” water use.” The DEQ specifies use of
rooftop runoff, closed tank storage, and where outdoor use is seasonal a
secondary runoff reduction drawdown practice. The intended means and
methods do not meet the DEQ rainwater harvesting system specifications
because a golf course is not a “roof top”” as intended by the regulations.
Please provide a DEQ-approved methodology to attain the required total
phosphorous reduction.
Revision 1 Response: As discussed after the plan review, the methodology
for adhering to quality requirements has been revised – rainwater
harvesting is no longer proposed (based on DEQ/County discussions that it
would require extensive time, research, and design efforts to verify
compliance).
Quality control is achieved through conservation area (in easements),
drainage through the conservation areas, and purchasing of nutrient credits.
The limits of now include proposed areas of development (approximately
205 acres) – the larger area of 270 acres has previously included golf course
area that will be converted to brush (native grasses, not regularly mowed).
Those areas have been removed from the current analysis.
Revision 1 Comments: We acknowledge that the quality control strategy has
changed. See new comments at the end of this section.
Acknowledged.
2. Please note that “brush” is not an identified land cover per the Virginia Runoff
Reduction Method (VRRM). Please revise the pre- and post-developed SWM
drainage area map to the reflect “brush” areas as “forecasted/open space”
and on VRRM spreadsheets.
Revision 1 Response: The information shown on this sheet (C403) is
provided for channel and flood protection computations and is not provided
for VRRM calculations. Brush is a land cover condi tion associated with
NRCS methodology – and as identified in the plan set, reference areas of
native grasses and other vegetated with minimal maintenance (clearing and
mowing).
Revision 1 Comments: Comments addressed.
Acknowledged.
3. With the respect to the pre- and post-developed drainage area map and the
land cover summary table on Sheet No. C403, please revise as follows:
a. Please verify that the impervious surface reported in sub -areas 2D and
2F reflect the surface of the existing pond located in each sub -area.
b. The existing parking lot area in sub-area 3B scales out at
approximately 2 acres. Please adjust drawings to reflect correct
impervious area in this sub-area and adjust VRRM calculations
accordingly.
Revision 1 Response: This information has been revised to only describe
areas with modified land cover conditions within the limits of disturbance.
The information submitted previously was provided to analyze flood and
channel protection, which is not longer applicable (refer to Comment #5).
Revision 1 Comments: Flood and channel protection analyses are still
required. See comment 5 below.
Acknowledged.
4. Please provide a calculation indicating the total surface area of existing
impervious cart paths, existing impervious cart paths to be demolished, and
new impervious cart paths to be constructed with this plan.
Revision 1 Response: New or demolished cart path areas have been
quantified, as identified on a new sheet C402. Existing cart paths (or other
impervious surfaces) outside the limits of work are not impacted with the
proposed development and not quantified.
Revision 1 Comments: Comment partially addressed. It appears that
additional impervious areas are now identified and shown on the plan,
including bathroom buildings and maintenance building additions. Please
identify within each of the 8 drainage areas the new impervious areas, existing
impervious areas and existing impervious to be demolished. These can be
added adjacent to the land summary tables on Sheet No. C404.
Per email from John Anderson with Albemarle county this comment
is void.
5. Outfalls #1, #2, #3, #4, and #5 are concentrated (channel flow) and thus
each outfall individually where it crosses the property is to be analyzed.
Please provide complete hydrology and hydraulic study establishing the pre-
and post-developed with onsite and offsite runoff volume/flow to each of
these outfall points to include routing of existing pond. Stage storage
calculations of existing ponds are to be provided as well.
Revision 1 Response: As discussed after plan review, the hydrologic
condition of the site is not significantly modified with the proposed
development. A new sheet, C402, has been provided to depict where
the land cover conditions have been modified. In general, the land
cover conditions vary from turf (CN=61) to forest (CN=55), and new
brush/meadow areas (CN=48). Proposed land cover conditions are
intended to balance the hydrologic conditions of the site, such that
cleared forest is mitigated with additional brush areas to achieve a
CN value for the drainage area that is equal to or less than the
existing conditions. Refer to sheet C404 for calculations.
Revision 1 Comments: Comment not completely addressed. We generally
agree with the concept verbiage, however appropriate hydrologic/hydraulic
calculations demonstrating compliance with 9VAC 25-870-66 flood protection
and channel protection are required. Please provide energy balance
calculations demonstrating flood protection.
Stormwater Quantity calculations have been provided and updated.
6. Add disturbed area limits to the pre- and post-developed drainage area maps
(Sheet Nos. C401 and C402).
Revision 1 Response: The limits of work have been added to the requested
sheets.
Revision 1 Comments: Please label the “limits of work” and add a symbol to
the legend on Sheet Nos.C401 and C402.
Limits of work has been labeled and legend has been updated. See
Sheets C401-C403.
7. Please provide complete VCD spreadsheet and VRRM spreadsheet. Only
parts/portions of these spreadsheets were provided.
Revision 1 Response: The VCD spreadsheet is no longer applicable, but
additional information on the VRRM spreadsheet has been provided on
sheet C407
Revision 1 Comments: The VCD spreadsheet is no longer applicable.
Acknowledged.
8. Please note that additional comments may be generated based on responses
to these comments.
Revision 1 Response: Acknowledged
Revision 1 Comments: Additional comments follow.
9. In order for us to verify that there are no C soils within the land cover
conversion/transition please add the soils to Sheet No. C402.
Soils information has been added to Sheet C402.
10. The acreages in the Land Summary Table for Drainage Area A (24.70 ac.)
does not match the BMP Selections Practice 9a and 9b combined acreage
(27.42 ac.) Please reconcile on the various VRRM worksheets.
VRRM worksheets have been reconciled. See Sheet C407.
11. On Sheet No. C404 complete the Drainage Area 8 pre and post developed
table inputs.
Drainage area tabulations have been revised. See Sheet C404.
12. The BMP practice areas are shown on Sheet No. C405. Please indicate the
drainage area to each BMP practice area. Please indicate the area of each
BMP practice area. We recommend that each area/practice be identified with
an alpha or numeric identifier. Please add soils mapping to Sheet No. C405 to
facilitate verification.
The requested information has been added to Sheet C405.
13. Please verify the impervious Pre-Redevelopment and Post-Redevelopment
Land Cover reported in Site Summary on Sheet No. C407. The impervious
surface is to be located within Drainage Area A.
VRRM has been revised. See Sheet C407.
14. In the previous submission the total disturbed acreage was reported as 276.80
acres, while the total disturbed acreage reported in this submission has been
reduced to 161.00 acre. Please explain the disturbed area reduction of
approximately 115.80 acres. Also, we note that the post -redeveloped
impervious area of 5.25 acres reported in the first submission has been
reduced to 3.20 acres in this submission. Please explain the reduction (i.e.
what changed).
The limits of disturbance was revised to eliminate all undisturbed areas.
15. Please include Soil Compost Amendment (VA DEQ SWMP Design Spec No.
4) Sections 6, 8 and 9 in their entirety on the plan.
This information has been added to the plans.
16. Please add the following 2 notes to the Vegetated Filter Strips Notes.
7. Stormwater should not be diverted into filer strip until the turf cover is
dense and well established.
8. Before Site work begins vegetated filter strip boundary should be clearly
marked.
These notes have been added to the plans. See Sheet C405.
17. Please provide an area calculation for the area disturbed in the existing buffer
areas.
This information has been added to the plans. It is the sum of the “EX golf
area to be redeveloped” (4.2 AC) and “New Golf Area” (0.80 AC). See
Sheet C408.
18. Please note that additional comments may be generated based on responses
to these comments.
Acknowledged.
D. Erosion and Sediment Control Plan (ESCP)
Virginia Code 62.1-44.15:55 requires the VESCP authority to approve or disapprove an
ESCP. This plan is disapproved, and the reasons are provided in the comments below.
The erosion control plan content requirements can be found in County Code Section 17 -
402.
1. Existing pre-development and post-development limits and clearing/grading
are not graphically depicted clearly on the drawings. Within the limits of
disturbance, please identify graphically where areas of existing trees are to be
demolished and which existing trees are to remain and provide square
footage or acreage for each area.
Revision 1 Response: Refer to sheet C402 for areas where land cover
conditions are modified (cleared forest, conversion of turf to brush, new cart
path, demolished cart path, and buffer mitigation areas).
Revision 1 Comments: Comments addressed except that symbol for
proposed brush in the legend does not match that shown on the plan.
Provide correct legend symbol on the plan.
The legend has been revised. See Sheet C402.
2. Please add limits of existing golf course verses limits of new golf course area
to the plan.
Revision 1 Response: The existing golf course, conversion areas, and new
golf course are shown through a series of sheets 401-403.
Revision 1 Comments: Comments addressed (See Part D, Item 1).
Acknowledged.
3. Some of the text is not legible due to scale. Please increase the font size,
type, or scale of the drawing so that all text and symbology are discernable.
Revision 1 Response: The relevant text has been modified to promote
legibility.
Revision 1 Comments: Comment addressed.
4. Please provide Albemarle County Engineering General Construction Notes
for Erosion and Sediment Control Plan Notes 1 through 22 on the plan.
Revision 1 Response: These notes have been added to the bottom right of
Sheet C500
Revision 1 Comments: Comment addressed.
5. Please provide wetland delineation mapping. Sheet No. C101 General Notes
Note #7 states no known wetlands or waters of the US exist within the site
area while Critical Areas Note #5 states wetlands onsite. Please reconcile
with Note #7.
Revision 1 Response: Note #6 in general notes referenced the wetlands, this
note has been removed.
Revision 1 Comments: Comment not addressed. Sheet No. C101 General
Note #6 references no known wetlands or water of the U.S., while Critical
Areas Note #5 states wetlands on site. Aga in, please reconcile.
These notes have been reconciled. See Sheet C101.
6. Sheet No. C101 Site Survey Information Note #3 references “Survey Limits”
shown heron were surveyed by Kirk Hughes and Associates. Please add
“Survey Limits” to the plan.
Revision 1 Response: Survey limits include the limits of information shown
on the existing conditions C201. Note #2 has been added to this sheet to
clarify that the limits of survey work are defined by the survey information
shown.
Revision 1 Comments: Comments not addressed. “Survey limits” not labeled
or clarified, i.e. what is shown on Sheet No. C201 is the “survey limits” and
whatever is shown outside of this area is GIS? Please verify.
This is correct. There is also a note on the Existing conditions sheet
stating this.
7. We note that existing ponds are to be used as sediment basins. Please
provide the following:
a. Please provide a temporary sediment basin design data sheet for each
existing pond facility that is to be used as a temporary sediment basin.
Revision 1 Response: The existing ponds will no longer be used as
sediment basins – a series of turbidity curtains, sediment traps, silt
fence, and other measures adjacent to work areas have been
proposed. The ponds are still planned for draining and dredging
(after upstream stabilization).
Revision 1 Comments: Comment no longer pertinent.
b. It is noted that existing ponds #2, #3, and #5 are to be drained and
dredged via pumping into the existing riser structure. The pumped
material is to be dewatered prior to release/outfall into the natural
drainage way/receiving channel. Please indicate that a dewatering
device is to be provided to include sizing calculations.
Revision 1 Response: The water will be drainage and pumped, the
dredged material will be managed separately from the pumping
operation.
Revision 1 Comments: Comment not addressed. Address Comment.
Per conversations with John Anderson the dredging shall be
permitted under a separate set of plans.
c. Please explain the intent/need for “earth baffles” for ponds #2 and
#3. Provide detail to include intended water surface elevation(s).
Revision 1 Response: These have been removed.
Revision 1 Comments: Comment no longer pertinent.
d. Please provide on the plan the total drainage area that is directed to
each of the existing ponds proposed to be utilized as a temporary
sediment basin (only the disturbed area to each facility is identified).
Revision 1 Response: The ponds will no longer be used as temporary
sediment basins.
Revision 1 Comments: Comment no longer pertinent.
8. The Special Use Permit (SP) is not approved. We can review but not approve
the ESCP until the SP is approved. Provide a sediment basin worksheet for
the proposed sediment basin located in the SP area.
Revision 1 Response: Acknowledged – a note is included for the area that
relies on the SUP, and notes that no work can begin in that area until the
SUP has been approved. The work in that area influences the overall
drainage conditions and quality analysis and is therefore considered in plan
and calculations.
Revision 1 Comments: We could not find the note referenced in the response
above. Please indicate to us where the note is located, i.e. sheet no.
This information is shown on Sheets C501 & C311.
9. Land disturbing activities are proposed in stream buffers and wetlands. An
Army Corps of Engineers permit to disturb wetlands must be obtained prior
to erosion and sediment plan approval. Please provide permit to disturb
wetlands. Also, a mitigation plan for disturbing wetlands and stream buffers
must be submitted and approved by Albemarle County prior to erosion and
sediment control plan approval. Not all required buffers are shown. Buffers
are required to be shown for existing ponds in drainage areas 2D and 2F from
their pond banks and their outfall streams that are within 100 feet of the limits
of disturbance. Also, existing ponds #2, #3, and #5 from their entire pond
banks and their outfall streams within 100 feet of the limits of disturbance are
to be included as well.
Revision 1 Response: As discussed and agreed upon during prior
conversations with the County, the buffer limits have been established and
are shown based on County requirements.
Revision 1 Comments: Acknowledged.
10. Provide either an alpha or numeric designation for each sediment trap to
facilitate reference.
Revision 1 Response: The sediment traps have been labeled for reference.
Revision 1 Comments: Comment addressed.
11. The temporary sediment traps are shown in a schematic fashion. The traps
are to be graded out on the plan with sediment trap grades tied into adjacent
grade.
Revision 1 Response: The sediment traps have been revised to tie to existing
grades.
Revision 1 Comments: Comment addressed.
12. The following sediment traps do not provide 67 C.Y. wet storage and 67 C.Y.
dry storage:
a. Sheet No. C502 – ST: 1.5 AC. At north-east corner of practice area
b. Sheet No. C502 – ST: 1.5 AC. At south-east side of hole #15 fairway
c. Sheet No. C504 – ST: 1.5 AC. At east side of hole #10 green
Revision 1 Response: The sediment trap sizes have been revised.
Revision 1 Comments: Comment addressed.
13. Please provide calculations to include drainage area, pipe diameter, and outlet
protection apron dimensions for the temporary slope drains (TSD) shown to
serve hole #3 (Sheet No. C503), hole #16 (Sheet No. C501), and hole #5
(Sheet No. C504). Extend clean water diversion to the inlet of the middle
TSD serving hole #5.
Revision 1 Response: The slope drain calculations have been provided on the
E&S sheets, and the clean water diversion has been extended.
Revision 1 Comments: Comment not completely addressed. Please provide
pipe diameters and outlet protection apron dimensions for each TSD.
This information has been added. See Sheets C501 & C504.
14. Please provide inlet protection on TSD adjacent to hole #16 as sediment
laden runoff is directed to this control measure.
Revision 1 Response: Inlet protection has been added to the TSD.
Revision 1 Comments: Comment addressed.
15. Super silt fence on the west side of existing pond (#5) and to the east of hole
#17 is proposed to be installed perpendicular to contour in several locations.
Super silt fence is to be installed on contour and not across contours. Place
super silt fence on tangents parallel to contours.
Revision 1 Response: Silt fence has been modified as required.
Revision 1Comments: Comments partially addressed. Super silt fence
between pond (5) and the green associated with hole #17 is still
perpendicular to the contour. Please correct.
This silt fence has been revised.
16. Other locations where silt fence or super silt fence or super silt fence is
installed across contour and is to be corrected on the plans:
a. Sheet No. C502 – west side of 3 tee boxes furthest from hole #9
b. Sheet No. C502 – east side of next to last tee box furthest from hole
#15
c. Sheet No. C503 – south side of green hole #8
d. Sheet No. C503 – west side of the two tee boxes directly east of hole
#7 green
e. Sheet No. C503 – all along south side of hole #7 green, fairway, and
tee boxes
f. Sheet No. C503 – east side of closest tee box to hole #10
g. Sheet No. C503 – north side of next to last furthest tee box from hole
#14
h. Sheet No. C503 – east side of tee boxes to hole #4
i. Sheet No. C504 – east, south, and west sides of hole #12 green
j. Sheet No. C504 – east side of hole #4 green
Revision 1 Response: Silt fence has been adjusted as needed.
Revision 1 Comments: Adjust silt fence for locations below where it has not
been done:
a. Not done.
b. Not done.
c. Not done.
d. Not done.
e. Not done.
f. Done.
g. Done.
h. Done.
i. Not done.
j. Done.
This silt fence has been revised.
17. Silt sock is not a Virginian Erosion and Sediment Control approved device.
Please adjust the plan accordingly to depict approved control measures or
submit a variation request.
Revision 1 Response: As discussed and agreed upon prior to plan submission,
this system is proposed in lieu of silt fence to facilitate frequent grading
adjustments within the work areas. For reference, this system is acceptable
by VDOT standards.
Revision 1 Comment: The Albemarle County Program Authority will allow
the use of silt sock. Silt sock is to be placed on contour. There are multiple
locations where silt sock is placed perpendicular to contour and is to be
corrected.
a. Sheet No. C501 – Fairways holes #16 and #17.
This silt sock has been revised.
b. Sheet No. C501 – Short Game/Course practice area southernmost
green.
This silt sock has been revised.
c. Sheet No. C502 – Silt sock called out but not graphically shown on
south side of hole #15 fairway. Graphically show silt sock location on
plan.
This silt sock has been revised.
d. Sheet No. C502 – Short Game / Course practice area, two locations.
This silt sock has been revised.
e. Sheet No. C502/C503 – Between hole #2 green and hole #3 tee
boxes.
This silt sock has been revised.
f. Sheet No. C503 – At 3 locations directly west of hole #3 tee boxes.
This silt sock has been revised.
18. The sub-area graphic on Sheet No. C505 does not delineate any sub -areas.
Delineate desired subareas on sub-area graphic.
Revision 1 Response: As defined in the narrative, the sub-areas will be
determined at the time of construction. The sub-area strategy is intended
to allow for work within areas of the site prior to installation of all E&S
controls. Sub-areas are anticipated to be series of golf course holes.
Revision 1 Comments: Comment not addressed. As a minimum show
intended phase/sub areas.
Per conversations with John Anderson this sheet has been removed
from the plans.
19. Please add retaining wall symbol to legend. Please add a note identifying that
retaining walls three feet in height and greater require a separate permit.
Please label maximum height of each retaining wall shown on Sheet Nos.
C302, C303, C304, C307, C308, and C309.
Revision 1 Response: Retaining walls have been removed.
Revision 1 Comments: Comment no longer pertinent.
20. Due to plan scale cannot discern separation between the 1-foot contours.
Therefore, label all slopes. Please note that slopes may not exceed 2:1and
slopes greater than 3:1 are to have low maintenance ground cover. These
areas are to be delineated on the plan with some type of symbol and added to
the legend.
Revision 1 Response: As discussed prior to plan submission, the grading
shown for the golf course areas is provided to depict approximate limits of
grading with schematic contours intended for reference. These contours
have been removed for clarity.
Revision 1 Comments: Comment not addressed. You were not asked to
remove contours and we understand that grading is schematic. Please
address the comment.
Contours have been added to the plans.
21. All existing and proposed storm sewers to include existing pond risers and
outfall structures are to be added to Sheet Nos. C501 through C504 to
include sizes.
Revision 1 Response: There is no proposed modification to existing risers
and outfall structures.
Revision 1 Comments: Comment not addressed. Please show existing storm
drain/sewer pipes with the limits of clearing and grading/disturbance/work, if
any, as requested.
None exist within the limits of work.
22. Please add all existing easements (access, drainage, sight, sanitary, etc.) with
deed book references, locations, and dimensions to the plans.
Revision 1 Response: Easements are shown on the plan sheets with DB/PG,
as shown in the site plan sheets C301-C311.
Revision 1 Comments: It appears that the only easement within the “limits” is
an RWSA sanitary sewer easement along the east side of the golf course
property. Please verify that this is the only easement within the “limits”.
RWSA easement is the only easement within the project limits.
23. Please show contractor staging and parking areas on the plans.
Revision 1 Response: Contractor areas are proposed within existing
parking/maintenance locations, and have been noted on the plan sheets.
Revision 1 Comments: A single location for a staging, storage and stockpile
area is shown on Sheet No. C502. Your response alludes to multiple
locations and plan sheets. Are there additional areas? Please advise.
There is only one staging and storage location has noted on the plans.
24. Please add inlet protection, culvert inlet protection, and outlet protection to
existing structures within the limits of disturbance.
Revision 1 Response: Existing structures within the limits of disturbance are
now shown with appropriate measures.
Revision 1 Comments: The plan sheets have been reviewed and no existing
storm drain structures were observed within the limits of disturbance. Please
instruct us as to the locations where “shown”.
No existing structures exist within the disturbed area.
25. Site Plan Notes #4 and #5 on Sheet No. C301 identify improvements not
shown on the WPO plan. The location of these items are to be shown on the
plan.
Revision 1 Response: These improvements have been added to the plan with
notes.
Revision 1 Comments: The locations of the improvements alluded to in your
response were not observed on the 2nd submission documents. Please
instruct us as to the locations where “added”.
This information is shown on Sheets C300-C311 and C501-C504.
26. Some of the text in the plan views on Sheet Nos. C301 through C311 is not
legible. Please make text legible.
Revision 1 Response: Text has been modified for legibility.
Revision 1 Comments: Comment addressed.
27. Please provide evidence of VDOT entrance permit for the existing
maintenance access road to US Route 250 where proposed construction
entrance is located.
Revision 1 Response: This entrance has been removed from the scope.
Revision 1 Comments: Comment addressed.
28. Please provide dust control symbol in legend and show locations on the E&SC
plan sheets.
Revision 1 Response: Dust control measures are described in the E&S
narrative.
Revision 1 Comments: Comment not addressed. Please provide the
requested information.
DC has been called out on the plans C501-C504.
29. Show stockpile plan location(s) on the E&SC plan sheets.
Revision 1 Response: XX
Revision 1 Comments: XX is not a response. Comment addressed per item
23.
30. Please provide temporary seeding and permanent seeding symbol in legend
and show locations on the E&SC plan sheets.
Revision 1 Response: Temporary and permanent seeding is addressed in the
E&S narrative.
Revision 1 Comments: Comment not addressed. Please provide the
requested information.
TS/PS has been added to the plans. See Sheet C501-C504.
31. Indicate existing sidewalk to be demolished on Sheet Nos. C501 through
C504.
Revision 1 Response: Sheet C402 shows areas of cart path that will remain,
be demolished, undergo maintenance, and new areas.
Revision 1 Comments: Sheet C402 is a 1” = 300; scale. Please show
requested information on Sheet Nos. C501 through C504 as requested.
This information has been added to Sheets C501-C504.
32. Please provide a key map on each erosion and sediment control plan Sheet
Nos. C501 through C504.
Revision 1 Response: Match lines are provided on the sheets.
Revision 1 Comments: The Program Authority rescinds the original comment.
Acknowledged.
33. The existing pond to the west of hole #16 (see Sheet No. C501) and to the
east of the short course area (see Sheet No. C502) is labeled “Possible Dam
Reconstruction and Repair. Clearing Required.” Either include appropriat e
erosion and sediment controls for the required reconstruction and repair
work or delete from plan.
Revision 1 Response: This note has been removed.
Revision 1 Comments: Comment addressed.
34. New Comment: Sheet C501 tie in sediment basin grades to a djacent grades.
Sediment basin has been tied in to adjacent grades, see Sheet C501.
We have included PDF copies of the plans and calculations for your review. If you have any
questions or comments, please feel free to give me a call at 434.295.5624.
Sincerely,
Craig Kotarski, PE
Principal
TIMMONS GROUP
YOUR VISION ACHIEVED THROUGH OURS.
May 11, 2018
Albemarle County
Dept. of Community Development
401 McIntire Rd, Rm 227
Charlottesville, VA 22902
608 Preston Avenue P 434.295.5624
Suite 200 F 434.295.8317
Charlottesville, VA 22903 www.timmons.com
RE: Birdwood Golf Course —VSMP Permit Plan Review — WP0201800016 -Comment
Response Letter
We have reviewed all of your comments from April 10, 2018 and made the necessary revisions.
The comments and plan edits have been coordinated with the County through a series of
meetings to discuss the revisions to the stormwater management and BMP strategies. Please
find our responses to the comments below in bold lettering.
A. Stormwater Pollution Prevention Plan (SWPPP)
The SWPPP content requirements can be found in County Code section 17-405. A
SWPPP must contain (1) a PPP, (2) an ESCP, (3) a SWMP, and (4) any TMDL measures
necessary.
1. The SWPPP was not found with this submittal. Design consultant is to
provide a SWPPP using the standard template from the county website.
The SWPPP has been provided with this submission.
B. Pollution Prevention Plan (PPP)
The PPP content requirements can be found in County Code section 17-404.
1. The PPP exhibit will need to be included in the SWPPP. Design consultant is
to provide a PPP exhibit using the standard template from the County
website.
The SWPPP has been provided with this submission.
C. Stormwater Management Plan (SWMP)
VSMP Regulation 9VAC25-870-108 requires the VSMP authority to approve or
disapprove a SWMP. This plan is disapproved, and the reasons are provided in the
comments below. The stormwater management plan content requirements can be
found in County Code section 17-403.
CIVIL ENGINEERING I ENVIRONMENTAL I SURVEYING I GIS I LANDSCAPE ARCHITECTURE I CONSTRUCTION SERVICES
1. The plan notes that this project constitutes redevelopment (development on
prior developed land) of the 276.8 -acre disturbed area, and thus the total
phosphorous load is to be reduced to below the pre -development total
phosphorous load by 20%. The plan proposes to utilize Virginia DEQ
Stormwater Design Specification No. 6 Rainwater Harvesting as the means to
reduce the total phosphorous load as required. The plan proposes to use the
existing pond #3 as the "storage tank/cistern," approximately 96 acres of golf
course -managed turf as the "rooftop," and irrigation of approximately 60
acres of golf course -managed turf over an 8 -9 -month period (seasonal
outdoor use) as the "non -potable" water use." The DEQ specifies use of
rooftop runoff, closed tank storage, and where outdoor use is seasonal a
secondary runoff reduction drawdown practice. The intended means and
methods do not meet the DEQ rainwater harvesting system specifications
because a golf course is not a "roof top"" as intended by the regulations.
Please provide a DEQ -approved methodology to attain the required total
phosphorous reduction.
As discussed after the plan review, the methodology for adhering to quality
requirements has been revised — rainwater harvesting is no longer proposed
(based on DEQ/County discussions that it would require extensive time, research,
and design efforts to verify compliance).
Quality control is achieved through conservation area (in easements), drainage
through the conservation areas, and purchasing of nutrient credits. The limits of
now include proposed areas of development (approximately 205 acres) — the
larger area of 270 acres has previously included golf course area that will be
converted to brush (native grasses, not regularly mowed). Those areas have been
removed from the current analysis.
2. Please note that "brush" is not an identified land cover per the Virginia
Runoff Reduction Method (VRRM). Please revise the pre- and post -
developed SWM drainage area map to the reflect "brush" areas as
"forecasted/open space" and on VRRM spreadsheets.
The information shown on this sheet (C403) is provided for channel and flood
protection computations and is not provided for VRRM calculations. Brush is a
land cover condition associated with NRCS methodology — and as identified in the
plan set, reference areas of native grasses and other vegetated with minimal
maintenance (clearing and mowing).
3. With the respect to the pre- and post -developed drainage area map and the
land cover summary table on Sheet No. C403, please revise as follows:
Please verify that the impervious surface reported in sub -areas 2D
and 2F reflect the surface of the existing pond located in each sub-
area.
b. The existing parking lot area in sub -area 3B scales out at
approximately 2 acres. Please adjust drawings to reflect correct
impervious area in this sub -area and adjust VRRM calculations
accordingly.
This information has been revised to only describe areas with modified land
cover conditions within the limits of disturbance. The information submitted
previously was provided to analyze flood and channel protection, which is not
longer applicable (refer to Comment #5).
4. Please provide a calculation indicating the total surface area of existing
impervious cart paths, existing impervious cart paths to be demolished, and
new impervious cart paths to be constructed with this plan.
New or demolished cart path areas have been quantified, as identified on a new
sheet C402. Existing cart paths (or other impervious surfaces) outside the limits of
work are not impacted with the proposed development and not quantified.
5. Outfalls #1, #2, #3, #4, and #5 are concentrated (channel flow) and thus each
outfall individually where it crosses the property is to be analyzed. Please
provide complete hydrology and hydraulic study establishing the pre- and
post -developed with onsite and offsite runoff volume/flow to each of these
outfall points to include routing of existing pond. Stage storage calculations
of existing ponds are to be provided as well.
As discussed after plan review, the hydrologic condition of the site is not
significantly modified with the proposed development. A new sheet, C402,
has been provided to depict where the land cover conditions have been
modified. In general, the land cover conditions vary from turf (CN=61) to
forest (CN=55), and new brush/meadow areas (CN=48). Proposed land
cover conditions are intended to balance the hydrologic conditions of the
site, such that cleared forest is mitigated with additional brush areas to
achieve a CN value for the drainage area that is equal to or less than the
existing conditions. Refer to sheet C404 for calculations.
6. Add disturbed area limits to the pre- and post -developed drainage area maps
(Sheet Nos. C401 and C402).
The limits of work have been added to the requested sheets.
7. Please provide complete VCD spreadsheet and VRRM spreadsheet. Only
parts/portions of these spreadsheets were provided.
The VCD spreadsheet is no longer applicable, but additional information on the
VRRM spreadsheet has been provided on sheet C407
8. Please note that additional comments may be generated based on responses
to these comments.
Acknowledged —
D. Erosion and Sediment Control Plan (ESCP)
Virginia Code 62.1-44.15:55 requires the VESCP authority to approve or disapprove an
ESCP. This plan is disapproved, and the reasons are provided in the comments below.
The erosion control plan content requirements can be found in County Code Section 17-
402.
Existing pre -development and post -development limits and clearing/grading
are not graphically depicted clearly on the drawings. Within the limits of
disturbance, please identify graphically where areas of existing trees are to
be demolished and which existing trees are to remain and provide square
footage or acreage for each area.
Refer to sheet C402 for areas where land cover conditions are modified (cleared
forest, conversion of turf to brush, new cart path, demolished cart path, and
buffer mitigation areas).
2. Please add limits of existing golf course verses limits of new golf course area
to the plan.
The existing golf course, conversion areas, and new golf course are shown through
a series of sheets 401-403.
3. Some of the text is not legible due to scale. Please increase the font size,
type, or scale of the drawing so that all text and symbology are discernable.
The relevant text has been modified to promote legibility.
4. Please provide Albemarle County Engineering General Construction Notes for
Erosion and Sediment Control Plan Notes 1 through 22 on the plan.
These notes have been added to the bottom right of Sheet C500
5. Please provide wetland delineation mapping. Sheet No. C101 General Notes
Note #7 states no known wetlands or waters of the US exist within the site
area while Critical Areas Note #5 states wetlands onsite. Please reconcile
with Note #7.
Note #6 in general notes referenced the wetlands, this note has been removed.
6. Sheet No. C101 Site Survey Information Note #3 references "Survey Limits"
shown heron were surveyed by Kirk Hughes and Associates. Please add
"Survey Limits" to the plan.
Survey limits include the limits of information shown on the existing conditions
C201. Note #2 has been added to this sheet to clarify that the limits of survey
work are defined by the survey information shown.
7. We note that existing ponds are to be used as sediment basins. Please
provide the following:
a. Please provide a temporary sediment basin design data sheet for
each existing pond facility that is to be used as a temporary sediment
basin.
The existing ponds will no longer be used as sediment basins — a series of
turbidity curtains, sediment traps, silt fence, and other measures adjacent
to work areas have been proposed. The ponds are still planned for
draining and dredging (after upstream stabilization).
b. It is noted that existing ponds #2, #3, and #5 are to be drained and
dredged via pumping into the existing riser structure. The pumped
material is to be dewatered prior to release/outfall into the natural
drainage way/receiving channel. Please indicate that a dewatering
device is to be provided to include sizing calculations.
The water will be drainage and pumped, the dredged material will be
managed separately from the pumping operation.
c. Please explain the intent/need for "earth baffles" for ponds #2 and
#3. Provide detail to include intended water surface elevation(s).
These have been removed.
d. Please provide on the plan the total drainage area that is directed to
each of the existing ponds proposed to be utilized as a temporary
sediment basin (only the disturbed area to each facility is identified).
The ponds will no longer be used as temporary sediment basins.
8. The Special Use Permit (SP) is not approved. We can review but not approve
the ESCP until the SP is approved. Provide a sediment basin worksheet for
the proposed sediment basin located in the SP area.
Acknowledged — a note is included for the area that relies on the SUP, and notes
that no work can begin in that area until the SUP has been approved. The work in
that area influences the overall drainage conditions and quality analysis and is
therefore considered in plan and calculations.
9. Land disturbing activities are proposed in stream buffers and wetlands. An
Army Corps of Engineers permit to disturb wetlands must be obtained prior
to erosion and sediment plan approval. Please provide permit to disturb
wetlands. Also, a mitigation plan for disturbing wetlands and stream buffers
must be submitted and approved by Albemarle County prior to erosion and
sediment control plan approval. Not all required buffers are shown. Buffers
are required to be shown for existing ponds in drainage areas 2D and 2F from
their pond banks and their outfall streams that are within 100 feet of the
limits of disturbance. Also, existing ponds #2, #3, and #5 from their entire
pond banks and their outfall streams within 100 feet of the limits of
disturbance are to be included as well.
As discussed and agreed upon during prior conversations with the County, the
buffer limits have been established and are shown based on County requirements.
10. Provide either an alpha or numeric designation for each sediment trap to
facilitate reference.
The sediment traps have been labeled for reference.
11. The temporary sediment traps are shown in a schematic fashion. The traps
are to be graded out on the plan with sediment trap grades tied into adjacent
grade.
The sediment traps have been revised to tie to existing grades.
12. The following sediment traps do not provide 67 C.Y. wet storage and 67 C.Y.
dry storage:
a. Sheet No. C502 — ST: 1.5 AC. At north-east corner of practice area
b. Sheet No. C502 — ST: 1.5 AC. At south-east side of hole #15 fairway
c. Sheet No. C504 — ST: 1.5 AC. At east side of hole #10 green
The sediment trap sizes have been revised
13. Please provide calculations to include drainage area, pipe diameter, and
outlet protection apron dimensions for the temporary slope drains (TSD)
shown to serve hole #3 (Sheet No. C503), hole #16 (Sheet No. C501), and
hole #5 (Sheet No. C504). Extend clean water diversion to the inlet of the
middle TSD serving hole #5.
The slope drain calculations have been provided on the E&S sheets, and the clean
water diversion has been extended.
14. Please provide inlet protection on TSD adjacent to hole #16 as sediment
laden runoff is directed to this control measure.
Inlet protection has been added to the TSD.
15. Super silt fence on the west side of existing pond (#5) and to the east of hole
#17 is proposed to be installed perpendicular to contour in several locations.
Super silt fence is to be installed on contour and not across contours. Place
super silt fence on tangents parallel to contours.
Silt fence has been modified as required.
16. Other locations where silt fence or super silt fence or super silt fence is
installed across contour and is to be corrected on the plans:
a. Sheet No. C502 — west side of 3 tee boxes furthest from hole #9
b. Sheet No. C502 — east side of next to last tee box furthest from hole
#15
c. Sheet No. C503 — south side of green hole #8
d.
Sheet No. C503
— west side of the two tee boxes directly east of hole
#7 green
e.
Sheet No. C503
— all along south side of hole #7 green, fairway, and
tee boxes
f.
Sheet No. C503
— east side of closest tee box to hole #10
g.
Sheet No. C503
— north side of next to last furthest tee box from hole
#14
h. Sheet No. C503 — east side of tee boxes to hole #4
L Sheet No. C504 — east, south, and west sides of hole #12 green
j. Sheet No. C504 — east side of hole #4 green
Silt fence has been adjusted as needed.
17. Silt sock is not a Virginian Erosion and Sediment Control approved device.
Please adjust the plan accordingly to depict approved control measures or
submit a variation request.
As discussed and agreed upon prior to plan submission, this system is proposed in
lieu of silt fence to facilitate frequent grading adjustments within the work areas.
For reference, this system is acceptable by VDOT standards.
18. The sub -area graphic on Sheet No. C505 does not delineate any sub -areas.
Delineate desired subareas on sub -area graphic.
As defined in the narrative, the sub -areas will be determined at the time of
construction. The sub -area strategy is intended to allow for work within areas of
the site prior to installation of all E&S controls. Sub -areas are anticipated to be
series of golf course holes.
19. Please add retaining wall symbol to legend. Please add a note identifying
that retaining walls three feet in height and greater require a separate
permit. Please label maximum height of each retaining wall shown on Sheet
Nos. C302, C303, C304, C307, C308, and C309.
Retaining walls have been removed.
20. Due to plan scale cannot discern separation between the 1 -foot contours.
Therefore, label all slopes. Please note that slopes may not exceed 2:1and
slopes greater than 3:1 are to have low maintenance ground cover. These
areas are to be delineated on the plan with some type of symbol and added
to the legend.
As discussed prior to plan submission, the grading shown for the golf course areas
is provided to depict approximate limits of grading with schematic contours
intended for reference. These contours have been removed for clarity.
21. All existing and proposed storm sewers to include existing pond risers and
outfall structures are to be added to Sheet Nos. C501 through C504 to
include sizes.
There is no proposed modification to existing risers and outfall structures.
22. Please add all existing easements (access, drainage, sight, sanitary, etc.) with
deed book references, locations, and dimensions to the plans.
Easements are shown on the plan sheets with DB/PG, as shown in the site plan
sheets C301 -C311.
23. Please show contractor staging and parking areas on the plans.
Contractor areas are proposed within existing parking/maintenance locations, and
have been noted on the plan sheets.
24. Please add inlet protection, culvert inlet protection, and outlet protection to
existing structures within the limits of disturbance.
Existing structures within the limits of disturbance are now shown with
appropriate measures.
25. Site Plan Notes #4 and #5 on Sheet No. C301 identify improvements not
shown on the WPO plan. The location of these items are to be shown on the
plan.
These improvements have been added to the plan with notes.
26. Some of the text in the plan views on Sheet Nos. C301 through C311 is not
legible. Please make text legible.
Text has been modified for legibility.
27. Please provide evidence of VDOT entrance permit for the existing
maintenance access road to US Route 250 where proposed construction
entrance is located.
This entrance has been removed from the scope.
28. Please provide dust control symbol in legend and show locations on the E&SC
plan sheets.
Dust control measures are described in the E&S narrative.
29. Show stockpile plan location(s) on the E&SC plan sheets.
XX
30. Please provide temporary seeding and permanent seeding symbol in legend
and show locations on the E&SC plan sheets.
Temporary and permanent seeding is addressed in the E&S narrative.
31. Indicate existing sidewalk to be demolished on Sheet Nos. C501 through
C504.
Sheet C402 shows areas of cart path that will remain, be demolished, undergo
maintenance, and new areas.
32. Please provide a key map on each erosion and sediment control plan Sheet
Nos. C501 through C504.
Match lines are provided on the sheets.
33. The existing pond to the west of hole #16 (see Sheet No. C501) and to the
east of the short course area (see Sheet No. C502) is labeled "Possible Dam
Reconstruction and Repair. Clearing Required." Either include appropriate
erosion and sediment controls for the required reconstruction and repair
work or delete from plan.
This notes has been removed.
We have included PDF copies of the plans and calculations for your review. If you have any
questions or comments, please feel free to give me a call at 434.327.1692.
Sincerely,
Cody Pennetti, PE
Project Manager