7906_Duke_DanRiver_RequestPhase1SubGrade_DIN27251_20170113

1
Frost, Larry
From:Martin, Melonie Y <[e-mail]>
Sent:Friday, January 13, 2017 10:50 AM
To:Frost, Larry
Subject:FW: Dan River Landfill Phase 1 Subgrade
Attachments:GroundwaterSeparation_Contour.5.pdf; GroundwaterSeparation_Contour1ft.pdf
Larry –  

Please see the revised email below that addresses your comments. 

Melonie

From: Martin, Melonie Y
Sent: Friday, January 13, 2017 10:14 AM
To: 'Frost, Larry'
Subject: FW: Dan River Landfill Phase 1 Subgrade

Larry –  

Below is a summary of what was discussed earlier this morning with Evan.  Please let me know if you concur 
with this approach or if modifications are required for your approval. 

Very respectfully, 
Melonie

From: Andrews, Evan
Sent: Friday, January 13, 2017 9:39 AM
To: Martin, Melonie Y
Subject: Dan River Landfill Phase 1 Subgrade

Melonie, 

As you are aware, Transash is finalizing grading of the landfill subgrade for certification prior to the placement of 
compacted clay liner.  Given the snow and freezing temperatures earlier this week, minor grading adjustments  (on the 
order to ½”) are next to impossible.  Transash has requested that they be able to strip the subgrade up to 6” below the 
permitted grades and begin the placement of the compacted clay liner at that, lowered, elevation.  AMEC provided the 
attached file showing that there is ample separation between the permitted subgrade to allow for a slightly lower 
elevation.  The basic process for liner construction would be as follows: 

1. Clip wet material from the landfill base grades in phase 1 to achieve a solid, dry foundation up to 6” below the 
permitted base grade.  This would only be done as needed and not across the entire phase.  Post settlement 
slopes would be maintained to preserve permitted drainage flow paths. 
2. Survey the new subgrade to establish a base line elevation to construction the remainder of the liner system 
3. Verify that the revised grading will not result in the pooling or ponding of any leachate on the liner system. 
4. Construct the 12” of 1x10‐5 from the lowered elevation 
2
5. Construct the geosynthetics portion of the double liner system 
6. Place intermediate cover in the cell to the permitted grades (thicker as needed in some areas to account for the 
lower base grades) to achieve zero net gain in landfill airspace. 

Please let me know if this is an acceptable approach or if there are any modifications required. 

Thank you, 

Evan Andrews, PE
DUKE ENERGY
Carolinas East Landfill Engineer
CCP Engineering
3191 Pine Hall Rd.
Walnut Cove, NC 27052

Office: 336-445-0734
Cell: 336-430-2988

Contour (.5ft)
High : 40.7
Low : 5.3
21.5
19
12
10
22
19.5
17.5
15
2 2 .5
2 0
98
7 .5
23
2 0 .5
18
15.5
1 2 .5 2
3.52
1
16
11.5
11
1310.59.5
8.5
7
393
0
2
7
24
2 322
8 .5 8
1098
9 .5 7
9
8.5
16
14
13.5
9 .5
8.5
1 0 9
87.5
6.5
8.5
8
8.58
7.5
7 8
7 .5
27
24.5
25.524
20
18.5
14.5
13.5
17
1 6 .5
1 4
3
6
.
5
31
26.5
25
1 9 .5
1 7
7.5
1 0 .5
8
15
1 0
24
14
12.5
12
1 2
31
30.52928
24
1 7
1 7 1 6
1 6
1 6
1 5
14.5
14.5
15
13
12
12.5
12
1 2 .5
11
1 0
9
7 .5
7
3
8
.
5
37
30
2 1 .5
1 6
1 6
14.5
14.5
1
3.
5
14
1 1 .5 12
1 1
11
1 0
1 0
1 0
9 .5 1 0
9
.
5
9.5
7 .5
8
7 .5
7
3
2
33
3
2
.5
31 30.53027.5 29 26.5
26
25.5
2 5
17
1 6
1 6
1 5
13.5
13
13
1 1
11
1 1 .5
11.5
8 .5
9
9
8.5
9 99
9
8
8
7 .5
7
7.5
6 .5
7
7
6.5
6
Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/AirbusDS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and theGIS User Community
PREPARED BY:
DATE:
CHECKED BY:
DATE:
Dan River Steam StationLandfill Subgrade
D o c u m e n t P a t h : F :\A M E C _P r o j e c t s \2 0 1 4 \7 8 1 0 -1 4 -0 0 6 5 D a n R i v e r P r o p o s e d L a n d f i l l \G I S \S e t t l e m e n t _2 0 1 5 1 1 1 0 \G r o u n d w a t e r S e p a r a t i o n .m x d
PROJECT NO:7810-14-0065FIGURE NO:
0 200100Feet ±
MS
CR
1/11/2017
1/11/2017
Groundwater Separation
5
Elevation (ft)
Contour (1ft)
High : 40.7
Low : 5.3
2221201918
1615
23
1 7
1 09
8
3
0
24
13
3
1
25
1
41
2
31
2524
1614
11
1 0
9
8
1 09
1 0 8
8
7
8 7
8
7
28
2 6
8
7
29
2
8
26
2 1
2 220
1 6
27
15
1 4
3
6
30
24 24
1 7
1 7
1 6
1 6
1 6
1 5
14
1212
12
12
1 1
11
10
9
8
39
3
8
37
34
32
2927
2 3
1 6
15
15
13
13
12
11
1
1
11
1 0
1
0
1 0
9
9
9
9
999
9
8
8
8
8
7
7
Source: Esri, DigitalGlobe, GeoEye, Earthstar Geographics, CNES/AirbusDS, USDA, USGS, AEX, Getmapping, Aerogrid, IGN, IGP, swisstopo, and theGIS User Community
PREPARED BY:
DATE:
CHECKED BY:
DATE:
Dan River Steam StationLandfill Subgrade
D o c u m e n t P a t h : F :\A M E C _P r o j e c t s \2 0 1 4 \7 8 1 0 -1 4 -0 0 6 5 D a n R i v e r P r o p o s e d L a n d f i l l \G I S \S e t t l e m e n t _2 0 1 5 1 1 1 0 \G r o u n d w a t e r S e p a r a t i o n .m x d
PROJECT NO:7810-14-0065FIGURE NO:
0 200100Feet ±
MS
CR
1/11/2017
1/11/2017
Groundwater Separation
5
Elevation (ft)