9204_Sorrell_CoverInspectionReport_DIN27926_20170607

S&ME, Inc. | 3201 Spring Forest Road | Raleigh, NC 27616 | p 919.872.2660 | f 919.876.3958 | www.smeinc.com

June 7, 2017
Ms. Jackie Drummond via email: [e-mail]
Division of Waste Management
217 West Jones Street
Raleigh, North Carolina 27603

Mr. James Easthom via email: [e-mail]
Kennon, Craver, Belo, Craig, & McKee, PLLC
P.O. Box 51579
Durham, North Carolina 27717
Reference: Landfill Cover Inspection – May 2017
Sorrell Landfill (Permit # 92-04)
Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Dear Ms. Drummond and Mr. Easthom:
On May 30, 2017, representatives from S&ME, Inc. (S&ME) performed a visual inspection of the landfill
cover and the storm water/surface water conveyance features at the closed Sorrell Landfill located in
Apex, North Carolina. This letter report is provided to document the findings of our inspection. Services
conducted by S&ME were performed in general accordance with S&ME Proposal No. P4258-07V, dated
April 25, 2007, the S&ME’s memorandum 2017 – Landfill Cover Maintenance Cost Estimate, dated March
16, 2017, and the NCDEQ memorandum Authorization to Conduct the 2017 Landfill Cover Maintenance at
the Closed Sorrell MSW Landfill, Wake County, Solid Waste Permit Number 92-04, dated March 20, 2017.
BACKGROUND INFORMATION
Sorrell Grading Company initially operated a construction and demolition (C&D) landfill at this site, which
subsequently also accepted municipal solid wastes (MSW) and similar waste materials. A Closure Plan and
a Post-Closure Plan for the landfill were prepared by Stuart Jones Consulting Engineering dated June 20,
1996 and submitted to the Section on behalf of Sorrell Grading Company. The Closure Plan provided
criteria for the construction of a landfill cover consisting of a clay cap over the top 24 acres of the landfill
and a vegetative layer of the top and side slopes of the landfill. The Closure Plan indicated that the side
slopes were already largely constructed at that time and that the cap construction was underway.

A Closure Report, dated September 7, 2001, was prepared by S&ME and submitted to the Section on
behalf of Sorrell. The report detailed S&ME’s evaluation of the landfill cover after the landfill had been
closed and the clay cap had been placed on top of the landfill. The Closure Report described testing of
the cover on the top and the side slopes of the landfill, verifying the placement and thickness of the
infiltration layer and the erosion layer. Locations on the side slopes and the top of the landfill were
tested. Most of the locations were found to contain adequate thicknesses of cap material. Where the
thickness of the cap was insufficient, these locations were identified and repairs were to be made by the
owner. Additional information on the construction and condition of the landfill cover system was
Landfill Cover Inspection – May 2017
Sorrell Landfill (Permit # 92-04)
Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251

June 7, 2017 2
described in S&ME’s letter report Response to Notice of Violations, submitted to NCDENR-DWM on
January 26, 2009.

The May 30, 2017 landfill cover inspection was limited to an evaluation of two areas of compliance:
1. Observation of the items noted by the Facility Compliance Inspection Report issued by the Solid
Waste Section (Section) on February 15, 2016.
2. A visual inspection of the landfill cap over the top 24 acres of the landfill and the storm
water/surface water conveyance features.

S&ME personnel did not inspect the landfill side slopes which are covered by growths of pine trees,
hardwoods and underbrush.
OBSERVATIONS
Overall, the cap and stormwater conveyance features appear to be in good condition with adequate
vegetation. Three deficiencies in need of corrective measures were observed. The following features were
visually identified as 1) deficient and in need of corrective measures, 2) as minor functional issues
requiring monitoring or 3) as functional and not in need of corrective measures. The numbered items
below correspond to the numbers on Figure 1 and to the numbered photos in the photographic log.
Deficiencies:
1. A slope failure was observed on the upper portion of the steep slope on northwestern portion of
the landfill property (photographs 1a-1b.) The slope failure was reported in the last two cover
inspections S&ME performed at the site.
2. Several areas of subsidence on the landfill cap appear to collect surface water after large rain
events (photograph 2). One of these areas is an area north of Slope Drain No. 2 and has been
described in previous reports as being adjacent to where grading was previously adjusted to
increase water drainage in front of Slope Drain No. 2. This area has been under observation for
the last several evaluation periods and has consistently been seen to store water after significant
rain events. The other areas were first identified in the previous report as storing water and are
described in greater detail under the minor functional issues section below.
3. A depression has formed on the southwest portion of the landfill cap, adjacent to the berm
where the access road, from the landfill cap to the lower access road along the southern border of
the landfill, crosses the berm (photograph 3). The depression behind the berm is preventing water
from draining off of the landfill cap, resulting in saturated soils. The depression within this area
has been degraded due to vehicle traffic while the soil is holding water and the depression has
become increasingly deeper.
Minor Functional Issues:
4. Several areas with standing water on the landfill cap were observed in the previous report and
were again observed during this inspection. The first of these areas is adjacent to the southern
edge of the landfill cap between landfill gas vents GV-2 and GV-3 (photographs 4a-4b).
5. Standing water was observed on the landfill cap adjacent to landfill gas vents GV-13 and VT-13 in
the northeastern portion of the landfill (photographs 5a-5b).
6. Standing water was observed on the landfill cap north of slope drain no. 1, which has previously
Landfill Cover Inspection – May 2017
Sorrell Landfill (Permit # 92-04)
Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251

June 7, 2017 3
been regraded to increase drainage (photograph 6). This area was not noted in the previous
report, and the standing water present may be an irregular occurrence due to multiple recurring
rain events in the weeks preceding this inspection.
7. Scouring below the stormwater outfall for the culvert draining the stormwater ditch parallel to the
southern access road has been observed in previous inspection reports. While a previous
inspection indicated that the outfall itself had experienced erosion, the outfall appears to be
stable despite several significant rain events since the last inspection (photograph 7).

8. The stormwater outfall for the pipe draining the stormwater ditch parallel to the southern access
road appears to be functioning based on evidence of water flow. There appears to be an area
where the pipe joints have become disconnected under the road (photograph 8). The
disconnected areas within the pipe should be monitored for erosion and scouring which could
impact the integrity of the road above.
9. A small slope subsidence was noted along the southern slope. The subsidence was approximately
1.5 feet deep and 2 feet wide. No trash is visible (photograph 9).
10. Scouring was observed in the outfall ditch below the newly installed slope drains at Diversion
Ditches/ Diagonal Water Bars Nos. 1 and 2 (photographs 10a-10b).
Functional Items:
11. The landfill cap and access roads have been mowed to remove excess grass and vegetation. This
maintenance item has been completed twice in the past year, improving conditions on site
substantially. The grass and vegetation are currently an acceptable height (photographs 11a-11b).
12. The vegetation growing on the western hill slope of the landfill cap has been mowed and
removed from the slope (photographs 12a-d). Bare spots of dead vegetation had previously been
observed along the northeast slope, which are currently growing vegetation and are stable.
13. The vegetation growing in and clogging the drainage ditch running parallel to the landfill along
the southern access road has been removed and treated. The ditch is functioning as designed
(photographs 13a-b).
14. The vegetation growing in and clogging slope drain inlets 1 and 2 and their associated headwalls
has been cut and removed. The slope drains have remained straight. The slope drain inlets and
their associated headwalls are functioning as designed (photographs 14a-d).
15. The vegetation previously growing in and clogging the headwall structures at the entrance of the
slope drains at water diversion bars No. 1 and 2 has been cut and removed (photographs 15a-b).
The slope of water diversion bar #2, which was previously repaired for erosion, is growing
vegetation and is currently stable.
16. The access roads along the landfill have been mowed to remove excess vegetation (photographs
16a-b).
17. The culvert located within the stream crossing northeast of MW-6 is functioning as designed
(photograph 17).
18. The sediment ponds along the western edge of the property appear to be functioning as
designed (photographs 18a-c).
Landfill Cover Inspection – May 2017
Sorrell Landfill (Permit # 92-04)
Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251

June 7, 2017 4
19. The trash rack on the outlet for the large sediment pond on the western portion of the site was
replaced during previous maintenance and is functioning as designed (photograph 19).

The approximate location of each of the above items is labeled on the attached Site Plan drawing (Figure
1).
RECOMMENDED CORRECTIVE MEASURES
S&ME recommends the following corrective measures for each observed item:
Deficiencies:
1. The slope failure should continue to be evaluated by a qualified professional to determine the
cause of the failure and repaired according to their recommendations to prevent further damage
to the landfill cap.
2. The area of subsidence, collecting surface water north of slope drain no. 2 has consistently been
observed to have standing water in consecutive inspections. To minimize water ponding on the
landfill cap above the buried waste, this area should be regraded to promote water drainage off
the landfill cap and stabilized with vegetation.
3. The depression behind the berm, within the access road, holding water, should be stabilized by
filling the depression with soil or gravelto prevent the depression from increasing in size, when
vehicles drive through this location when soil is saturated.
Minor Functional Issues:
4. The areas with standing water should be monitored to determine whether this is a regular
occurrence. Should the standing of water continue to be observed on the cap, these areas should
be graded so water will drain off the landfill cap.
5. The areas with standing water should be monitored to determine whether this is a regular
occurrence. Should the standing of water continue to be observed on the cap, these areas should
be graded so water will drain off the landfill cap.
6. The areas with standing water should be monitored to determine whether this is a regular
occurrence. Should the standing of water continue to be observed on the cap, these areas should
be graded so water will drain off the landfill cap.
7. Rip rap had previously been installed within the stormwater outfall where scouring was occurring.
While the previous inspections indicated that the rip rap was being relocated within the outfall
during high flow events, there has been no additional scour or rip rap relocation in the outfall
since the last inspection. The outfall should continue to be monitored for any further rip rap
displacement or scour below the outfall. If further damage is observed, larger rip rap should be
installed to prevent further degradation of the outfall and to prevent relocation of the newly
installed rip rap during high flow periods.
8. The disconnected joint in the pipe should be monitored for evidence of scouring or erosion
between the joints. Should the level of erosion or scouring reach levels where it could impact the
integrity of the road, the pipe should be repaired or replaced.
9. The small slope subsidence should be monitored for an increase in depth or size. If the area
Landfill Cover Inspection – May 2017
Sorrell Landfill (Permit # 92-04)
Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251

June 7, 2017 5
increases in size, it should be filled, graded, and stabilized with vegetation. The subsidence has
not increased in size since first observed.
10. The scouring below the outfalls for the slope drains in the Diversion Ditches/ Diagonal Water Bar
Nos. 1 and 2 should be monitored for further erosion. Should further erosion be observed, efforts
should be undertaken to stabilize the eroded areas.
Functional Issues:
S&ME recommends that the landfill cap continue to receive regular, bi-annual mowing of the landfill
cap in the spring and fall to promote the health of the vegetative cover.
CLOSING
S&ME appreciates the opportunity to provide these services and hopes that you find this report to be
complete and informative. We would appreciate an opportunity to discuss our findings and
recommendations with you. Please call us at [phone] if you have any questions or comments, or if
we can be of further assistance.
Sincerely,
S&ME, Inc.

Ashley Steele Samuel P. Watts, P.G.
Staff Scientist Senior Project Manager
[e-mail] [e-mail]

Attachments:
Attachment I - Facility Compliance Inspection Report, dated February 15, 2016
Attachment II - Photographic Log
Attachment III - Figure 1 – Cover Inspection Site Map

T:\Projects\2007\ENV\07-251 Sorrell Landfill\Reports\2017 June Landfill Cover Inspection\Landfill Cap Evaluation Report - June
2017.docx

Attachment I
Facility Compliance Inspection Report, dated February 15, 2016

FACILITY COMPLIANCE INSPECTION REPORT
Division of Waste Management
Solid Waste Section

Page 1 of 4

UNIT TYPE:
Lined
MSWLF LCID YW Transfer Compost SLAS COUNTY: WAKE
Closed
MSWLF X HHW White
goods Incin T&P FIRM PERMIT NO.: 9204-MSWLF-1981
CDLF Tire T&P /
Collection Tire
Monofill Industrial
Landfill DEMO SDTF FILE TYPE: COMPLIANCE

Date of Site Inspection: January 15, 2015 Date of Last Inspection: July 7, 2015

FACILITY NAME AND ADDRESS:
Sorrell Landfill
SR 1302 (Smith Road)
Apex, North Carolina 27502

GPS COORDINATES: N: 35.7029 W: -78.8131

FACILITY CONTACT NAME AND PHONE NUMBER:
Mrs. Shirley Sorrell
Mr. James Easthom, Kennon Craver, PLLC, 919-490-0500, [e-mail]

FACILITY CONTACT ADDRESS:
Mrs. Shirley Sorrell
Sorrell Grading Company, Inc.
6610 Holly Springs Road
Raleigh, NC 27606

PARTICIPANTS:
Liz Patterson, NCDENR-Solid Waste Section

STATUS OF PERMIT:
Closed Unlined MSW/Demo Landfill

PURPOSE OF SITE VISIT:
Partial Inspection to monitor fall maintenance work completed first week of November 2015.

STATUS OF PAST NOTED VIOLATIONS:
NONE

OBSERVED VIOLATIONS:
NONE

The item(s) listed above were observed by Section staff and require action on behalf of the facility in order to come into or maintain compliance
with the Statutes, Rules, and/or other regulatory requirements applicable to this facility. Be advised that pursuant to N.C.G.S. 130A-22, an
administrative penalty of up to $15,000 per day may be assessed for each violation of the Solid Waste Laws, Regulations, Conditions of a Permit,
or Order under Article 9 of Chapter 130A of the N.C. General Statutes. Further, the facility and/or all responsible parties may also be subject to
enforcement actions including penalties, injunction from operation of a solid waste management facility or a solid waste collection service and
any such further relief as may be necessary to achieve compliance with the North Carolina Solid Waste Management Act and Rules.
FACILITY COMPLIANCE INSPECTION REPORT
Division of Waste Management
Solid Waste Section
Page 2 of 4

ADDITIONAL COMMENTS
The Sorrell Grading Company was operating the unlined landfill for disposal of municipal solid waste, construction and
demolition waste, and land clearing and inert debris, at least as early as 1973. In 1981, the facility was permitted by the
NC Department of Human Resources, Division of Health Services, Solid & Hazardous Waste Management Branch as a
sanitary landfill. Landfill operations ceased in June of 1994. A Permit for Closure was issued by the Solid Waste Section
on October 6, 2011. A total of 65.21 acres are included within the landfill facility boundary.

1. This inspection was conducted to monitor ongoing site conditions after fall maintenance performed the first
week of November 2015 under direction of S&ME.

2. Several candy-cane tops on passive vents observed during the inspection are tilted. The flexible rubber
couplings vents have been fitted appear to have been adjusted, tightened, and are working on most. A few still
need some more adjustment to hold the top of the vents straight in place.
GV-4 tilted vent on passive vent GV-5 tilted vent on passive vent

3. The cap is currently well vegetated. Fall maintenance work has been completed under the direction of S&ME.

View of the cap looking east on January 15, 2016 View of the cap looking east on January 15, 2016

FACILITY COMPLIANCE INSPECTION REPORT
Division of Waste Management
Solid Waste Section
Page 3 of 4

4. The vegetation surrounding both Slope Drains #1 and #2 has been cleared. The rerouted flexible pipe for both
drains still appears to be a straighter run down the slope which has helped maintain proper functionality of the
slope drains.
Flexible pipe (drain #2) – January 15, 201 Slope Drain #1 Inlet/Headwall - January 15, 2015

5. Rip rap drainage ditches along the perimeter road have been clear-cut during general maintenance. Periodic
removal of this vegetation is needed to maintain proper drainage from the cap.

6. The perimeter road and road across the cap were mowed November 2015. Evidence of recent vehicular traffic
was apparent on the cap and depressions were filled with stormwater. Signs of vehicular traffic were also
apparent adjacent to the perimeter road where vehicles appeared to be entering the landfill footprint from an
adjacent natural gas easement.
Evidence of vehicular traffic on western edge of landfill

7. Sediment ponds are functioning as designed.

FACILITY COMPLIANCE INSPECTION REPORT
Division of Waste Management
Solid Waste Section
Page 4 of 4

Please contact me if you have any questions or concerns regarding this inspection report.

Phone: [phone](O) 919-805-6499 (C)

Liz Patterson
Environmental Senior Specialist
Regional Representative

Sent on:2-15-2016 X Email Hand delivery US Mail Certified No. [ _]

Copies: Jason Watkins, Field Operations Branch Head – Solid Waste Section
Jaclynne Drummond, Compliance Hydrogeologist - Solid Waste Section
Jessica Montie, Compliance Officer – Solid Waste Section
Sam Watts, S&ME, [e-mail]
KK Land Inc, 2203 Good Shepherd Way, Apex, NC 27523-6947
Sirrhan Griffin and Joseph Griffin, 2124 Trefoil Ln, Fuquay-Varina, NC 27526-5348

Attachment II
Photographic Log

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
1

1a View of small portion of slope failure on the northwestern
slope looking across the hill (east).
1b View of small portion of slope failure on the northwestern
slope looking uphill (west).

2 View of area on landfill cap north of Slope Drain No. 2
observed to have standing water (looking east).

3 View of muddy depression adjacent to landfill berm within
the access road connecting the landfill cap and the access
road along the southern landfill boundary.

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
2

4a View of area with standing water observed between
landfill gas vents GV-2 and GV-3 looking east.
4b View of area with standing water observed between
landfill gas vents GV-2 and GV-3 looking west.

5a View of area with standing water observed between
landfill gas vents GV-13 and VT-13 looking north.
5b View of area with standing water observed between
landfill gas vents GV-13 and VT-13 looking west.

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
3

6 View of area with standing water observed between north
of slope drain no. 1, looking north.
7 View of displaced rip rap and increased erosion within
outfall of the culvert draining the stormwater ditch parallel
to the southern access road.

8 View of the pipe connecting the ditch north of the southern
access road to the ditch south of the access road along
the southern property boundary (looking southwest).
9 View of small slope subsidence in landfill cap on southern
slope just north of MW-8 (looking north).

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
4

10a View of scouring at outfall of slope drains installed within
Diversion Ditch/ Diagonal Water Bar no. 1.
10b View of scouring at outfall of slope drains installed within
Diversion Ditch/ Diagonal Water Bar no. 2.

11a Overall view of recently mowed grass and vegetation
across the landfill cap (looking west).
11b Overall view of recently mowed grass and vegetation
across the landfill cap (looking east).

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
5

12a View of the recently mowed back (western) slope of the
landfill cap looking downhill from the top of the cap.
12b View of the recently mowed back (western) slope of the
landfill cap looking downhill from the top of the cap.

12c View of the recently mowed back (western) slope of the
landfill cap looking uphill from the access road.
12d View of the recently mowed back (western) slope of the
landfill cap looking uphill from the access road.

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
6

13a View of ditch along the southern base of the landfill
looking west.
13b View of ditch along the southern base of the landfill
looking west.

14a View of Slope Drain #1 Inlet/ Headwall, which has recently
had the woody vegetation removed (looking south).
14b View of flexible slope drains from Slope Drain Inlet #1
(looking northwest).

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
7

14c View of Slope Drain #2 Inlet/ Headwall, which has recently
had the woody vegetation removed (looking south).
14d View of flexible slope drains from Slope Drain Inlet #2
(looking north).

15a View of Diversional Ditch/ Diagonal Water Bar #1 (looking
south).
15b View of Diversional Ditch/ Diagonal Water Bar #2 (looking
south).

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
8

16a View of recently mowed access road to monitoring well 4
(looking east).
16b View of mowed access road to monitoring well 7 (looking
north).

17a View of culvert located within stream crossing northeast of
MW-6. The culvert is functioning as designed (looking
northwest).
17b View of culvert located within stream crossing northeast of
MW-6. The culvert is functioning as designed (looking
southeast).

Evaluation of Landfill Cap
Sorrell Landfill, Apex, Wake County, North Carolina
S&ME Project No. 1054-07-251
Taken by: A. Steele Date Taken: 5/30/2017
9

18a View of sediment pond outlet. The sediment pond is
functioning properly (looking northeast).
18b View of sediment pond and sediment pond inlet. The inlet
and sediment pond are functioning properly (looking
northeast).

18c View of outlet for small sediment pond along the western
edge of the property and of pond (looking east).
19 View of outlet for small sediment pond along the western
View of sediment pond and sediment pond outlet. The
outlet and trash rack are functioning properly.

Attachment III
Figure 1 – Cover Inspection Site Map
PROJECT NUMBER:
DATE:F
I
G
U
R
E

N
O
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SCALE:
DRAWN BY:
CHECKED BY:DRAWING NUMBER:WWW.SMEINC.COM
3201 SPRING FOREST RD, RALEIGH, NC 27616
NC ENGINEER LICENSE #F-0176
1
BTR1054-07-251
DEC. 20121" = 200'
SORRELL LANDFILL
APEX, NORTH CAROLINA
SITE MAP
B-2054
S:\PROJECTS\2007\07-251 Sorrell Landfill\CAD\B2054.dwg, FIG1, 12/18/2012 2:02:06 PM, 1:1