SW1190801_Response Letter_4-29-20 _5/12/2020

403 E. Market Street ■ Johnson City, TN 37601
[phone] ■ Fax [phone]
www.matternandcraig.com
Michael S. Agee
Steven A. Campbell
Randy W. Beckner
Bradley C. Craig
Wm. Thomas Austin
David P. Wilson
James B. Voso
Randy L. Dodson
Chad M. Thomas
Jason A. Carder
Edwin K. Mattern, Jr. (1949-1982)
Gene R. Cress (1935-2014)
Sam H. McGhee, III (1940-2018)
Stewart W. Hubbell (Retired)
J. Wayne Craig (Retired)
April 29, 2020

Jim Farkas
N.C. Department of Environmental Quality
Division of Energy, Mineral and Land Resources
1612 Mail Service Center
Raleigh, North Carolina 27699

Re: Leicester Volunteer Fire Department
Commission No. 3827

Dear Mr. Farkas:

The information presented herein corresponds to your previous comments dated January 16, 2020
and is intended to address or clarify each respective concern as follows:
1. November 22, 2019 Comment 12 –
a. For bioretention cell 1, the bottom surface elevation is 2,167 ft, the depth of the
bioretention cell is 3.5 ft and the minimum required separation from the SHWT is
2 ft which means that the SHWT must be at or below 2,161.5 ft at this location.
The closest boring to this bioretention cell is boring B-03 which terminates at
2,169 ft (7.5 feet short of the maximum allowable SHWT elevation). The second
closest boring is B-04 which terminates at 2,168 ft (6.5 feet short of the maximum
allowable SHWT elevation).

A test pit was constructed to observe the SHTW for bioretention cell 1. Please see the
attached report.

b. For bioretention cell 2, the bottom surface elevation is 2,155 ft, the depth of the
bioretention cell is 3.5 ft and the minimum required separation from the SHWT is
2 ft which means that the SHWT must be at or below 2,149.5 ft at this location.
The closest boring to this bioretention cell is boring B-12 which terminates at
2,162.5 ft (13 feet short of the maximum allowable SHWT elevation). The second
closest boring is B-11 which terminates at 2,174 ft (24.5 feet short of the
maximum allowable SHWT elevation).
Mr. Jim Farkas
Leicester Volunteer Fire Department
12/13/2019
Page 2 of 4

A test pit was constructed to observe the SHTW for bioretention cell 2. Please see the
attached report.

c. Please provide location specific soil borings that show that the SHWT is at least 2
ft lower than the lowest excavated point of each bioretention cell (Bioretention
MDC 1).

Please see the attached report.

2. November 22, 2019 Comment 19 – Per the Manual, Part C-0, the maintenance easement
is,

“The entire footprint of the SCM system…, plus an additional ten or more feet
around the SCM to provide enough room to complete maintenance tasks. This
SCM system includes the side slopes, forebay, riser structure, SCM device, and
basin outlet, dam embankment, outlet, and emergency spillway.”

Please ensure that the requisite areas are included in the maintenance access and is shown
on the plans (General MDC 8).

Please see Sheet C400 for the 10’ maintenance access around each bioretention cell.

3. Please correct the following issues with the Supplement-EZ Form:
a. Drainage Areas Sheet:
i. Please fill out the “Entire Site” column with information for the entire site
(Everything within the property boundaries).

Please see updated Supplement-EZ Form.

ii. Please include information for Line 5. This is the total amount of BUA in
proposed conditions within the entire site/drainage area.

Please see updated Supplement-EZ Form.

iii. Please include information for Line 7. This is the new (net increase)
amount of BUA that will be added to the entire site/drainage area. Line 7
should be the sum of the items on Line 10 and should not take into
account any existing BUA on the site in existing conditions (For this
project, existing BUA should be reported on line 13).

Please see updated Supplement-EZ Form.

Mr. Jim Farkas
Leicester Volunteer Fire Department
12/13/2019
Page 3 of 4

iv. Please include information for Line 16. The percent BUA is the total
amount of BUA in proposed conditions (Line 5) divided by the total area
of the entire site/drainage area, expressed as a percent.

Please see updated Supplement-EZ Form.

v. Please include information for Line 20. Drainage Area 1 contains a BUA
of type “Other” please elaborate on line 20 what this other type of BUA is.

The square footage from “other” is now included in the parking square footage.

vi. For Drainage Area 2, the off-site information (Lines 8 & 9) does not
match the table in Section IV, 10 of the Application. Line 8 of the
Supplement-EZ Form should include the total (pervious and impervious)
off-site portion of the drainage area whereas line 9 should only include the
BUA located within the off-site portion of the drainage area.

Please see updated Supplement-EZ Form.

b. Bioretention Cell Sheet:
i. Line 9 – Sheet C401 does not appear to show a drawdown orifice for
dewatering. Please revise for consistency.

Please see updated Supplement-EZ Form.

ii. Line 18 – This item is applicable as it is required for Bioretention MDC 1.
If a boring is conducted to a depth of 2 ft below the lowest point of the
proposed facility and the SHWT is not encountered, the SHWT depth may
be expressed as “< ####” where #### is the lowest elevation of the boring.

Please see updated Supplement-EZ Form.

iii. Line 19 – This elevation should be the elevation of the excavated bottom
of the facility This depth should be 42 in lower than the planting surface
elevation (30 in of media mix, 4 in of washed sand, and 8 in of #57 stone).

Please see updated Supplement-EZ Form.

iv. Line 26 – Since IWS is proposed for the bioretention cells, the in situ soil
infiltration rate is not needed.

The rate is listed as “N/A” for both bioretention cells.

Mr. Jim Farkas
Leicester Volunteer Fire Department
12/13/2019
Page 4 of 4

Sincerely,
MATTERN & CRAIG, INC.

Jacob Grieb, P.E.
Project Manager