4117_A1SandRockCDLF_Comment_Phase3_PTCApp_FID1257537_20181102

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Chao, Ming-tai
From:Chao, Ming-tai
Sent:Friday, November 02, 2018 10:49 AM
To:'Garrett, David'
Cc:[e-mail]; Ritter, Christine; Aja, Deborah
Subject:Comments on the PTC application Phase 3, A1 Sandrock CDLF, 41-17
Hi David:

I review the engineering portions of the revised PTC Application for Phase 3 (FID 1256891) received on
10/18/2018 and have several comments on the application below:

FID 1257537
1. (Section 1.2.1 & Drawing S2) What are material or recyclable stored in the Temporary Storage A
through E as shown on Drawing S2? The Section 1.2.1 should provide the descriptions of each storage
area including, but not limited to, the waste streams or products, maximum storage volume and extent,
leachate prevention (for waste) and BMPs for diverting stormwater/run-on or run-off, etc. A summary
table listing the extent (in acreage) and volume (in cubic yard) of each storage area and potentially
stored material or recyclable (because the recyclable is moving around as described in the Section) will
be acceptable.

2. (Sections 1.2.2 & 1.3.2)
i. The Phase 3 operational sequence includes 3A, 3B, & 3C as described in Table 1B of the Section
1.3.2 which is inconsistent with the descriptions in Section 1.2.2. Please clarify.
ii. In Section 1.2.2, the proposed excavation will be up to 15 feet to reach the proposed base grade
for Phase 3 is likely inconsistent with the maximum cutting depth as shown on Drawing No, X2
(referring the excavation depth around Boring B-33). Please clarify.

3. (Table 1B and Drawing No. S1)
i. The capacities of the Phases 3 & 4 and the gross capacity are inconsistent as shown Table 1B and
those described in Drawing No. S1.
ii. Should the capacities shown on Drawing No, S1 be correct, the various volumes stated in
Sections 1.3.2, 1.3.4, 8.2.2 including operating capacity for each phase or sub-phase, operational
& final soil cover, etc. must be recalculated accordingly.

4. (Section 2.4.4) The descriptions in this section are inconsistent with Drawing Nos. EC1 through EC3.
Please clarify.

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5. (Sections 4.1.1.3, 5.1.4, 5.9.1, 5.13, 5.9.1, 6.4.2, 7.1.1, 7.3.5, & 8.2.4) Change NCDENR to
NCDEQ. Please correct the typos.

6. (Section 5.4.1) In Section 5.4.1 states that recyclable is processed and stored in containers within Phase
1 footprints. This statement is inconsistent with that in Section 1.2.1 regarding temporarily storage areas
being located outside C&DLF footprints. Please clarify.

7. (Section 6.4.6) Why the maximum volume of EACH unprocessed (raw material or waste) and processed
material stockpiles shall be 1200 CY? In Section 6.4.7, 6,000 CY is the maximum volume for either
wood/LCID wastes or inert debris –concrete/aggregate.

8. (Section 6.4.7) The content of maximum volume of unprocessed inert debris is confusion. The
maximum volume of “unprocessed inert debris” is proposing of 6,000 CY, but the note “*’ indicates the
inert debris excludes concrete, rock, and soil. So please define this “unprocessed inert debris” which
can be temporarily stored on site up to 6,000 CY.

9. (Table 6A) No sludge (including those generated from a wastewater treatment plant) can be received at
the Processing Facility. Please make a correction.

10. (Section 8.1.2) The minimum frequency/density for gas vent is three vents per acre as described in this
Section. For the closed landfill cap encompasses 25.5 acres, the number of vents will be up to 77 vents,
but 33 vents (less than half of the expected number of vents) are proposing and shown on Drawing No.
EC5, and 66 vents is included in the cost estimate for site closure. Please provide a consistent number
of vents to be installed over the closure cap. The Drawing No. EC5, Table 8A & Section 10 may be also
subject to revision based on the correct number of gas vents.

11. (Table 8C) 12 perimeter gas probes shall be sampled/monitored quarterly each year. Unit cost per probe
sampling is $500.00 as shown in the cost table, and the annual cost shall be $24,000.00, not
$12,000. Provide the revised cost estimates in Table 8C & Section 10.

12. (Section 9.2) Per 15A NCAC 13B .0545, the assessment monitoring program at A-1 Sandrock C&DLF
is required due to exceedance of constituent(s) of concern being detected in water quality monitoring
events. Please revise the Water Quality Monitoring Program by adding the required assessment
monitoring program to this Section.

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13. (Sections 9.2.1 & 9.3) The Drawing No. M1, not MP1, shows the monitoring locations. The monitoring
network on Drawing No. M1 covers C&DLF – Phases 1 through 4, not Phases 1 & 2. Please make
necessary corrections.

14. (Drawing No. X2) On Cross Section G-G’ the vertical distance around boring B-33, Station 925 to 1075,
between the Estimated Long-Term Seasonal High-Water Level and the Adjusted Base Grade of the
landfill Phase 3 is likely much less than 4-feet.
Please contact myself, if you have any questions on the comments.

Ming-Tai, Chao
Environmental Engineer, Solid Waste Section
Division of Waste Management
North Carolina Department of Environmental Quality
919.707-8251 (Office)
[e-mail]