20110309 Ver 4 _Addendum to permit application _20180409

Addendum to permit application

Existing Site Conditions
The approximately 62 acre project area includes overgrown open areas and mixed
hardwood/pine forest. The area is adjacent to the existing Onslow limestone quarry. The USDA Soil
Survey of Onslow County shows that the soils within the project area are mapped as Norfolk with a
small amount of Goldsboro and Lynchburg. A man made open water tributary which becomes a stream
flows across the project area. The stream flows into an unnamed tributary to the New River.
The quarry opened in 1995. The site location was selected due to the strategic location and the
depth of limestone. Previous permits from USACE have been issued under the following Action IDs.
199400588, 200500582, SAW-2011-00666, SAW-2016-01209. Previous Water Quality Certifications
have been issued under DWR Project: 2011-0309.

Description of Avoidance, Minimization, and Compensation
Martin Marietta is limited in directions that we can expand the Onslow Quarry. Expansion
without an impact to waters of the US is impossible at this time. Expanding our north-east pit to the
north avoids impacts to a larger stream and wetland system. This larger system flows from below our
plant site and below our southern pit to converge and flow north. It continues flowing to the north side
of Duffy Field Road, bisecting the property until it flows into another unnamed tributary on the north
side of our proposed expansion area. In the past we have impacted this stream with a crossing but have
avoided expanding through it by creating a new pit to the west. We are avoiding these higher quality
Streams and their adjacent wetlands by expanding through a lower quality channel with no adjacent
wetlands.
Martin Marietta currently holds a Nationwide Permit to expand our northeast pit to the north,
through a manmade tributary that flows into an intermittent channel. This permit and the associated
Water Quality Certification are attached as Exhibit A. Our original plan was to avoid this intermittent
channel, leaving it and a 50ft buffer extending into our pit area. Through further planning, we have now
determined that this is not practicable due to safety and haul truck logistics, and loss of revenue
resulting from not mining below the channel. This proposed plan is attached as Figure 1 and Figure 3.
We are also proposing to expand into a small wetland (Figure 2) in order to eliminate a blind turn in our
haul road that has caused safety concerns. These items are further discussed below in our alternatives
analysis.

Alternatives Analysis
Alternative 1: (No Action Alternative)
Mining through previously permitted open water only.
Martin Marietta is currently permitted to mine through 0.25 acre of an open water tributary by
a Nationwide 39 under Action ID SAW-2016-01209 and DWR Project 2011-0309v3. This “No
Action Alternative” would avoid direct impacts to 1260 linear feet stream channel, denoted as
Stream A on the attached maps. However, indirect impacts would still occur. Once mining
commenced in the area, Stream A would extend into the pit, with a northern and southern slope
that reach from the stream buffer to the pit floor. Flow to the stream would be cut off and the
stream and its buffer would be essentially on top of a hill. Haul trucks driving around the edge
of the pit would have to travel around the Stream A buffer, adding approximately ½ mile to the
haul distance and creating a blind “hairpin” turn as shown in figure 4. On a daily basis our
trucks would travel approximately 60 extra miles, causing them to take fewer trips per day,
consume more fuel per haul, release more fuel emissions per ton of product, and reduce the life
of each truck.
The blind hairpin turn at the end of the Stream A buffer would also create a safety hazard. The
road will be used by both haul trucks and other passenger vehicles. Loaded these haul trucks
can weigh up to 100 tons. Martin Marietta values each employee and visitor at each of our sites
and prioritizes the safety of each individual first and foremost. Endangering employees,
customers, and visitors with a potentially unsafe haul road is unacceptable to Martin Marietta.
Avoiding this Stream also causes MM to leave behind approximately 375,000 recoverable tons
of limestone. This tonnage represents approximately $5.6 million in lost sales revenue.
During a recent mining permit modification, the DWR reviewed the recently issued NW39
permit and threatened to revoke the 401 Water Quality Certification if MM does not apply for
an individual permit to impact Stream A. This email is attached as Exhibit B.
In summary, based on the explanations above, the no-action alternative, which would not
involve discharge into waters, is not practicable.

Alternative 2: (Preferred Alternative)
Mining through entire reach of intermittent stream
Onslow Quarry currently has approximately 5 to 8 years of permitted reserves. In order to
extend the life of the quarry, MM needs to expand the pit. Expanding the pit to the north will
extend the life of this quarry to 11 to 15 years. As discussed in Alternative 1, a stream channel
and a manmade open water tributary, which flows into it, are located between the current pit
and approximately 5 million tons of reserves. As shown in Figure 1, mining through the stream
avoids the problems associated with alternative 1, such as the blind haul road turn. This
alternative would impact 104 linear foot of perennial Stream, 1,156 linear foot of Intermittent
Stream and 0.01 acre of wetland. NC Stream Assessment (NCSAM) forms have been completed
in the presence of the Corps of Engineers and the Division of Water Resources. These forms and
results are attached as Exhibit C. Working from the results of the NCSAM evaluation, MM
proposes to mitigate at a 2:1 ratio for impacts to 104 linear feet of perennial stream and at a 1:1
ratio for impacts to 216 linear feet of intermittent stream.
To further improve the safety of the Quarry, MM proposes to impact an additional 0.14 acre of
wetland located in the south western corner of the pit, as shown in Figure 2. Figure 4 shows
that there is currently a blind turn in this location which has been an ongoing safety hazard. At
this time passenger vehicles are not allowed to travel this section of haul road without first
contacting the haul trucks on radio. MM proposes to mitigate for this impact, 0.14 acre, and the
impact to 0.01 acre of wetland shown in Figure 1, at a 2:1 ratio.
MM believes that this is the only practicable alternative. The safety concerns associated with
the blind hairpin turn, extra cost and time due to a longer material haul, and loss of reserves
under the stream make avoiding these impacts impracticable.

Alternative 3:
Expanding in other directions.
Martin Marietta has extensively explored expanding the Onslow Quarry in other directions.
Expanding to the western pit to the west is limited by the property boundary.
Hwy 258 and Union Chapel Church Rd limit our expansion to the east. Duffy Field Road also
bicects the quarry site and is a limiting factor on where we can expand.
Connecting the eastern and western pits would impact approximately 12 acres of wetland and
over 3000 linear feet of stream. This alternative would not extend the life of the mine as much
as the preferred alternative, and has much greater environmental and floodplain impacts.
Therefore this alternative is not the least environmentally damaging alternative and is not
practicable at this time.
Expanding the southern pit to the south could impact as much as 10 acres of wetland and
several thousand linear feet of stream. This alternative could extend the life of the quarry as
much as our preferred alternative, but with more impacts to streams and wetlands it is not the
least environmentally damaging alternative at this time.
The stream and wetland systems to the south and through the middle of the property are higher
quality systems than the stream we are proposing to impact.

Offsite alternatives:
Offsite alternatives were not evaluated. An offsite alternative would not meet the Project
Purpose as described in block 19 of the permit application.

Mitigation for impacts
Martin Marietta proposes to mitigate for 216 linear feet of intermittent stream channel at a 1:1
ratio, 104 linear feet of perennial stream channel at a 2:1 ratio and 0.15 acre of wetland at a 2:1 ratio by
purchasing 424 warm water stream credits and 0.3 Riparian wetland Credits from Bachelors Delight
Mitigation Bank. Please see the letter dated February 27, 2018 Attached as Exhibit D.

Floodplain
The project would involve 0.15 acre of impacts to the 100 year floodplain. These impacts are shown in
the attached map, Figure 5. A Floodplain Development permit was issued by the Onslow County
Planning and Development Department on March 15, 2018. This permit is attached as Exhibit E.

Endangered Species Act (ESA)
A Query of the North Carolina National Heritage Program database indicates that there are no records
for rare species, important natural communities, natural areas, or conservation/managed areas within
the proposed project boundary.

National Historic Preservation Act (Section 106)
Martin Marietta is not aware of any properties or structures that are listed or eligible for listing with the
National Register of Historic Properties within the immediate vicinity of the project area.