20140332 Ver 1_BakerResponseToIRTComments_20150827

Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

August 27, 2015

Jeff Schaffer
NCDENR, Division of Mitigation Services
1652 Mail Service Center
Raleigh, NC 27699-1652

Subject: Response to IRT Comments for Revisions to Final Mitigation Plan
Browns Summit Creek Mitigation Project, Guilford County
Cape Fear Cataloging Unit 03030002
USACE AID SAW 2014-01642, DMS Project # 96313

Dear Mr. Schaffer:

Please find enclosed our responses to the Inter-Agency Review Team (IRT) review comments dated
July 14th and July 30th of 2015 in reference to the Browns Summit Creek Mitigation Project –Draft
Mitigation Plan in Guilford County, NC. We have revised Final Draft Mitigation Plan document in
response to the referenced review comments and have included those revisions for review. Each
comment/response has been grouped per the NCIRT reviewer and is outlined below.

Todd Bowers, USEPA, 16 July 2015
1. Table 1; Page 2-1: R1 Drainage area is listed as 438 acres. This is not consistent with other values
such as Table 4.1 (448 acres)
Response: Drainage area discrepancies throughout the Mitigation Plan have been checked and
revised where needed and are as follows in acreage: R1 = 438, R2 = 299, R3 = 242, R4 = 138, R5 = 24,
R6 = 61, T1 = 55, T2 = 47, T3 = 41, and T4 = 10.
2. Page 1-2: Recommend adding “restore stream and floodplain connectivity” in list of bulleted
primary goals especially since wetland hydrology performances are depending on it.
Response: As requested, we have included “restore stream and wetland connectivity” in the primary
goals of both the Executive Summary and in Section 1.0.
3. Page 1-2: Stated objectives should be measurable (as well as specific, attainable, reasonable and
trackable). Improvement, as well as degradation, in water quality is measurable. If this is the case
then Baker should be measuring water quality for at least some parameter to demonstrate that this
objective has been achieved. Performance standards relating to water quality, especially if tied to
the BMPs (R6 and T4), should be developed accordingly.
Response: The stated goals and objectives listed in both the Executive Summary and Section 1.0 have
been revised to reflect the method (implementation of standard best management practices) proposed
for the reduction of non-point source loads instead of a vague statement for improving water quality.
Because the methods chosen for the reduction of non-point source loading are commonly used for their
effectiveness, we feel that additional monitoring of such parameters and development of performance
standards are not needed. The revisions are as follows:

Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

Goals:
 Address known and obvious water quality and habitat stressors present on site.
Objectives:
 Construct a wetland BMP on the upstream extent of R6 to capture and retain stormwater run-off
from the adjacent cattle pastures to allow for the biological removal of nutrient pollutant loads
and for sediment to settle out of the water column
 Construct a step pool BMP channel to capture and disperse stormwater volumes and velocities
by allowing discharge from a low density residential development to spread across the
floodplain of Reach 4 thereby diffusing energies and promoting nutrient uptake within the
riparian buffer
The credit ratios for both BMPs were established during a site visit on June 4, 2014. During that site
visit, IRT members and Baker staff agreed that the implementation of the following BMPs and
associated enhancement measures would yield a 1.5:1 credit ratio for the valley length of the entire
BMP:
1) The conversion of the existing farm pond along R6 to a wetland type feature with a low-
maintenance weir outlet, the stabilization of the channel upstream and downstream of the BMP
2) The stabilization of a migrating headcut along T4 by implementing a rock lined step-pool
channel that will dissipate into a plunge pool that will detain the runoff and allow for dissipation
into the floodplain,
3) The exclusion of cattle from the entirety of the reach within the easement,
4) The treatment of invasive species, and/or
5) The replanting of the riparian buffer.
Currently there are no performance criteria for BMPs and none were specified by the IRT during this
meeting or during following site visits or subsequent conversation; therefore, no performance criteria
were developed. See the attached meeting minutes for reference. Please note that the meeting
minutes will also be included in the Appendix of the Mitigation Plan.
4. Page 2-2; last paragraph: R2 and R1 are not second-order streams, especially if R3 and R4 are
considered first-order. The inclusion of T-2 (zero order) does not change the stream order of the
main stem.
Response: The stream order error has been corrected and revised as follows: “The zero-order streams
include Reaches R5, R6, T1, T2, T3, and T4. The first-order streams include Reaches R1, R2, R3 and R4.”
5. 2.2.1; Page 2-3 first paragraph: Land use percentages of the “watershed” are not consistent with
those listed on Page 1-1 and Table 4.1. The “watershed” in question changes from an 83-square
mile HUC to the project watershed with differing percentages in one comparison and same
percentages in another comparison. Recommend making this clearer in the document.
Response: To more clearly define that we are discussing the Brown’s Summit project drainage area
and not the entire watershed, we have revised the paragraph to read as follows: “Land use within the
project’s drainage area (438 acres) is approximately 79 percent agricultural, 14 percent forested, and
5 percent developed, with approximately 90 percent of stream reaches lacking adequate riparian
buffers.”
6. 4.0 Baseline information: Some water quality parameter(s) should be included in order to
demonstrate that 1) the water quality is impaired and needs improvement and 2) that
improvements to water quality, a stated objective, has been achieved. Fecal coliform or E. coli might
be a suitable parameter in this case since we are dealing with cattle exclusion.
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

Response: Baker understands the reasoning behind the request to include baseline measurements for
water quality parameters to show existing impairments to water quality and validate improvements
to water quality from the project’s implementation; however, we feel that these measures are
unnecessary. We feel that the visual evidence of environmental stressors such as unrestricted cattle
access to the project tributaries, eroding and degraded stream banks, lack of riparian buffer, and
manure deposition does provide sufficient documentation that degradation in the form of excess
sedimentation and fecal contamination is highly probable. Thereby the removal of these stressors and
implementing common restoration practices that fence cattle out of the stream, stabilize eroding
stream banks, and vegetate the riparian corridor will result in the reestablishment of a healthy and
productive ecosystem that will provide bank stability and will allow for natural nutrient removals
through biological processes.
7. Table 4.1: Project Drainage Area does not match R1 Drainage Area and 2.2.1
Response: Please see our response to Comment No. 1, above.
8. Table 4.1: Missing 7 percent of land use classification?
Response: The Cape Fear River Basin Restoration Priorities 2009 Report does not classify the
remaining 7% of the drainage basin. However, in order to clarify, we have added the following text to
Section 1.0, “The designated land use of the remaining seven percent subwatershed remains
unclassified” and have also updated Table 4.1 to reflect this clarification.
9. Table 5.1: BMP Elements. Both Elements state that improvement in water quality is part of the
Purpose/Function. How do we know that this will be achieved successfully?
Response: To better articulate the purpose/function of the BMPs, Table 5.1 has been revised as
follows:
Element Location Purpose / Function
SW Reach R6
Detain runoff to reduce discharge velocities,
allow for sediment to settle out of the water
column and to allow for the uptake of nutrient
loads from biological processes
NI Reach T4
Detain runoff to disperse stormwater volumes into
the floodplain of Reach 4, reduce discharge
velocities, and promote nutrient uptake within the
riparian buffer
10. 7.1.3, Page 7-2: Live stake density appears erroneous. “40 stakes per 1,000 square feet” should read
“400 stakes per 1,000 linear feet” This will achieve the spacing required.
Response: This error has been corrected and we have revised the live stake density to correctly state
“400 stakes per 1,000 linear feet”. This correction was also updated throughout the remainder of the
document.
11. Page 7-5, last paragraph: “Reducing streambank sediment loading and removing cattle will provide
ecological uplift by improving water quality…” Once again a water quality objective is stated with
no baseline data or plans to collect data to support this statement. Recommend collecting baseline
water quality data to provide evidence that ecological lift has (or has not) been achieved. The
statement in the following paragraph does provide for removing the inputs via cattle exclusion but
that does not present measurable data that water quality itself is better and if so by how much.
Response: Please see our response to Comment No. 6, above. Baker has also revised sentence four in
paragraph 8 and removed sentence three in paragraph 9 of Section 7.3 on pages 7-5 and 7-6, to
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

eliminate unsubstantiated references to water quality improvements. Sentence 4 of paragraph 8
reads as follows:
“Stabilizing streambanks, revegetating riparian buffers, and removing cattle along project reaches
will provide ecological uplift by reducing nonpoint source loading to the receiving waters and
promoting the restoration of diverse aquatic and terrestrial habitats appropriate for the piedmont
ecoregion and landscape setting.”
12. 9.0, Page 9-1 and 9.2, Page 9-3: No performance standard is given for tree heights at 5 years (7’)
and 7 years (10’). Recommend adding this performance standard unless Baker can justify why this
cannot be achieved.
Response: We recognize that average height recommendations are listed as performance
standards for success criteria in Year 5 and 7 in draft guidelines circulated by the IRT in 2011;
however an official revision to the 2003 stream mitigation guidelines has not been produced.
Approximate heights by species will be recorded as part of an overall assessment of vigor to
determine whether the buffer appears to be on an acceptable trajectory, but given uncertainties in
precipitation, variations in species growth rates and soil heterogeneity the assignment of an
arbitrary blanket average is inadvisable.

13. 9.2, Page 9-3: First paragraph mentions R7. Remove R7
Response: R3 should have been included instead of R7; therefore, we have replaced R7 with R3. The
revised text is stated as follows: “No monitoring quadrants will be established within the undisturbed
wooded areas of Reaches R3, R4, R5, and R6”.
14. 9.2, Page 9-3: Vegetation monitoring addresses riparian buffer monitoring and plot density. It is
unclear how wetland vegetation monitoring will be conducted. Recommend at least one plot per
wetland type/area in addition to monitoring riparian buffer vegetation.
Response: Vegetation monitoring was inadvertently specified for riparian buffer areas. Instead it
should have been stated that vegetation monitoring would be conducted within randomly placed
vegetation plots throughout the planted buffer; therefore, the reference to “riparian” has been deleted
and currently reads as follows: “…within the planted buffer areas…”. In order to ensure
representative monitoring of vegetation within riparian, upland, and wetland communities, the
vegetation plots have been relocated to encompass the different community types throughout the
planted easement area, as needed. Figure 9.1 has been revised to depict the updated vegetation plot
locations.
15. 17.1.1.1, Page 17-1: R3 and R2 drainage areas do not match Table 1 in Site Selection
Response: Please see our response to Comment No. 1, above.
16. Tables 17-7 and 17-8: Design Estimates and Proposed Bankfull Velocities for R1, R2, R3 and R4 do
not match.
Response: We have revised bankfull velocities in Table 17-7 to match those in Table 17-8.
17. 17.5.1, Page 17-46: Are three automated groundwater wells enough coverage for monitoring five
wetland types? It appears that six stations are going to be installed per Figure 9.1 on page 9-6
Response: Section 17.5.1 is describing pre-construction condition analysis within the proposed
project wetland areas; however, the number of pre-construction groundwater wells was incorrectly
stated. The number of wells should be six, not three. Section 17.5.1 has been renumbered and is now
listed as Section 17.5.4 and the text has been revised as follows: “Six automated groundwater wells
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

were installed within project area to evaluate the pre-construction hydrologic conditions of the site”.
Post-construction ground water data collection is discussed in Section 9.3.1.
18. 17.7.2, Page 17-51: Live stake density appears erroneous. “40 stakes per 1,000 square feet” should
read “400 stakes per 1,000 linear feet” This will achieve the spacing required.
Response: Please see our response to Comment No. 10, above.
19. Tables 17.10 -12: Planting plan appears excellent for both riparian buffer and wetlands.
Response: Thank you very much.
Ginny Baker/Sue Homewood, NCDWR, 1 June 2015
1. Monitoring wells should be installed along intermittent reaches that are proposed for priority 1
restoration to ensure a minimum of 30 consecutive days of base flow is maintained during a normal
growing season. One well should be installed in the upper part of the reach for R4 (in the
intermittent section if this overlaps with P1 restoration), reach T1 and reach T3.
Response: Baker will install one pressure transducer within the thalweg of T1, T3, and the
intermittent portion of R4. In addition, a flow camera will be installed with each in-stream transducer
to collect a continuous series of remote photos over time and an on-site rain gage will document
rainfall. This data will be used to subjectively evaluate channel flow conditions throughout the year.
These devices will be inspected on a quarterly/semi-annual basis to document surface hydrology and
provide a basis for evaluating general flow response to rainfall events and surface runoff during
various water tables levels throughout the monitoring period. See Figure 9.1 for the approximate
location of the additional devices. A sub-section called “Flow Documentation” has been added to
Section 9.1 to reflect this addition. This sub-section is now listed as 9.1.2 and the remainder sub-
sections within this section have been renumbered accordingly.
2. The hydrology success criteria proposed for wetlands located in the lower end of the project along
reaches 1 and 2 are inconsistent. The 12% success standard for a normal precipitation year
proposed for the wetland type 2 (degraded) and wetland type 3 (partially functioning) seems
appropriate for a riverine/riparian associated wetland.. The 6% hydrology success standard
proposed just upstream for wetland type 4 (filled), which is the same type of wetland, does not
seem appropriate, especially as a 1:1 credit ratio is proposed. In addition, a 9% hydrology standard
(which NC DWR finds acceptable for a headwater wetland associated with a first order stream) is
proposed further upstream closer to the headwaters along Reach 4 in wetland type 5 (filled). NC
DWR understands Baker is concerned that only removing fill and using the E1 approach rather than
P1 restoration which would raise the channel and increase flooding may not result in the same level
of hydrological uplift as along Reach 1 where P1 restoration is proposed. Perhaps the 1:1 ratio
should be adjusted if only a partial hydrological uplift for wetland type 3 is achieved.
Response: The hydrologic success criteria for Wetland Type 4 has been revised to 12% so that all the
wetland areas along both Reach 1 and 2 are consistent. The second and third sentences in paragraph
two of Section 9.3.2 have been revised as follows: “The success criteria for wetland hydrology will
follow a range from 9-12 percent, depending on the specific wetland location and the mitigation
activity proposed. The wetland areas along Reach R1 and the large bend of Reach 2 will meet success
criteria for wetland hydrology when the soils are saturated within 12 inches of the soil surface for 12
percent of the growing season or twenty eight (28) or more consecutive days during the growing
season (229 days).“ The third paragraph in Section 9.3.2 has been removed.
3. Please add a vegetation plot to Wetland type 5, which is already established with mature
successional species.
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

Response: A vegetation plot has been located in Wetland Type 5 within the riparian corridor
adjacent to the newly aligned Priority I channel. Figure 9.1 has been revised to show the vegetation
plot in Wetland Type 5.
4. NC DWR would like more design specifications to be provided in in the final mitigation plan for the
two proposed BMPs. For the Constructed Wetlands, reference has been made to the BMP manual.
The plans should clearly identify all key elements of the design with regards to requirements in
either the BMP manual or the new MDC for Constructed Wetlands with explanations for any
deviations from the typical design requirements. The BMP Supplement Form may provide
guidance for what details to provide in future design documents. Regenerative Stormwater
Conveyances (RSCs) as proposed for T4 on Table 7.1, page 7-4, are not in the NC BMP Manual so it
is unclear what design standard will be used for the RSC NC DWR would recommend that RSC
designs adhere to the Anne Arundel County, MD or the West Virginia design standards for RSCs,
available at http://www.aacounty.org/DPW/Watershed/StepPoolStormConveyance.cfm and/or
http://www.dep.wv.gov/WWE/Programs/stormwater/MS4/Documents/Specification_4.2.7_Rege
nerative_Stormwater_Conveyance_WV-SW-Manual-11-2012.pdf.
Response: Two stormwater BMPs will be implemented within the project extents. A constructed
wetland will be implemented along Reach R6 and a rock lined step pool channel stormwater control
measure will be implemented along Reach T4. Design elements within the Mitigation Plan have been
revised to include the following documentation.
The constructed wetland was designed to detain discharge quantities from the 1-inch rainfall event. A
V-notched weir will be implemented to slowly release discharges over a 48 hour period thereby
reducing downstream discharge velocities. The extended draw down time will also allow for
sediments to settle out of the water column and for the uptake of nutrients from wetland plantings.
The constructed wetland was designed to meet stormwater pollutant removal rates using the design
parameters outlined in the NCDENR BMP Manual. Design elements for the constructed wetland will
include the following wetland zones:
 Deep Pools:
o Non-Forebay: 18-36” (include one at the outlet structure for proper drawdown).
o Forebay: 18-36” plus additional depth for sediment accumulation (deepest near inlet to
dissipate energy, more shallow near the exit).
 Shallow Water (low marsh): 3-6”.
 Shallow Land (high marsh): Up to 12”. This is the depth of the temporary pool.
 Upland: Up to 4 feet above the shallow land zone.
The BMP along Reach T4 was incorrectly labeled as a regenerative stormwater control measure. It
should have been listed as a rock lined step pool channel stormwater control measure as agreed upon
during onsite meetings on April 14 and June 20, 2014. The BMP will be created to stabilize a
migrating headcut on Reach T4 that is located at the outfall of a 30-inch stormwater culvert which
drains much of the Broad Ridge Court subdivision. The rock-lined step-pool channel will be
constructed to bring the stormwater runoff from the outlet to the floodplain elevation. A properly-
sized basin will capture the runoff, diffuse its energy, and allow water to spread across the vegetated
floodplain, promoting nutrient uptake within the buffer. A stable outlet channel will be constructed to
deliver the runoff to the project reach.
Both BMPs will be included in the project conservation easement and its fencing perimeter. Design
details are included in the plan set. BMP design calculations for the constructed wetland are included
in Appendix.
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

5. The BMP success standards and objectives for R6 and T4 need further description in Section 9.4.
Please describe what performance standards will be used to document that the BMPs are providing
functional uplift to the mitigation project.
Response: As discussed in Comment No. 3 (above) under the heading “Todd Bowers, USEPA, 16 July
2015”, the credit ratios for both BMPs were established during a site visit on June 4, 2014. During that
site visit, IRT members and Baker staff agreed that the implementation the BMPs and associated
enhancement measures would yield a 1.5:1 credit ratio for the valley length of the entire BMP for
which performance criteria was not stipulated. Currently there are no performance criteria for BMPs
and since none were specified by the IRT during this meeting or during following site visits or
subsequent conversation, no performance criteria were developed. See the attached meeting minutes
for reference. Please note that the meeting minutes will also be included in the Appendix of the
Mitigation Plan.
6. How will the two BMPs be maintained in perpetuity after the site is closed out?
Response: Baker understands that the long term maintenance for the proposed BMPs can be a
concern; therefore, they have been designed and located to eliminate the need for long term
maintenance needs by:
1. Stabilizing channel erosion
2. Installation of a low maintenance weir.
3. Extending the conservation easement and buffer plantings approximately 15 - 30 feet beyond the
footprint of the BMP to allow the buffer vegetation to act as pre-treatment feature for both
suspended sediment and nutrient loads,
4. Implementing permanent fencing outside the easement to ensure permanent livestock exclusion,
5. Providing a stable outlet mechanism/spillway for the BMPs
6. Provide stormwater draw down for the constructed wetland in R6 to maintain downstream
stream functions while maintaining a storage capacity only to support the permanent pool.
In addition, Baker will be providing post-construction monitoring and maintenance, as needed, during
the monitoring years thereby facilitating the wetland and riparian vegetation to become established
and functioning as intended prior to project closeout.
Andrea Hughes, USACE, 26 July 2015
1. Section 2.2: The mitigation plan indicates that another category of wetlands has been added to the
plan during mitigation plan development. During mitigation plan development, the Corps made
numerous visits to the Brown’s Summit site and held several discussions regarding changes to the
mitigation plan associated with proposed mitigation activities and determination of mitigation
credits. The intent of on-site meetings and discussions is to resolve concerns or issues associated
with the mitigation proposal prior to submitting the draft mitigation plan. At no time during the
course of these meetings was the proposal to add another category of wetlands to the mitigation
plan in order to generate additional credits discussed with the Corps and/or the IRT. Please
remove from the mitigation plan those areas located adjacent to Reach 4 and identified as “5-
hydrologic Reestablishment, 1:1 credit ratio” on Figure 9.1. No mitigation credits will be generated
for these areas.
Response: Baker’s intent for inclusion of Wetland Type 5 was to help us meet our contracted amount
of WMUs for the project. On 8/6/2015, Scott King (Baker) contacted Andrea Hughes (USACE) to
discuss the reasoning for Baker’s inclusion of the Wetland Type 5. Mr. King explained that:
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

“We are not seeking to expand our contracted WMU credit payment. We are only trying to ensure
that we fulfill our contracted amount. Only after credit ratio negotiations for the bulk of wetland
areas located at the bottom of the project were concluded did we fully realize we would be slightly
short (0.08 credits) of our contracted amount”. ….”we are only seeking 0.08 acres of paid credit
from 0.27 acres of restored wetlands.” – per follow-up email from Mr. King to Ms. Hughes on
8/6/2015 summarizing the noted phone conversation.
Upon the close of this conversation, Ms. Hughes understood the basis for the inclusion and found the
approach acceptable. A copy of the email will be included in the Appendices of the Mitigation Plan.
2. Section 8.1: Regarding the proposed BMPs, Table 8.1: Routine Maintenance Components states that
the stormwater management devices will be monitored and maintained per the protocols and
procedures defined by the NCDWR Stormwater BMP Manual (BMP manual). Please list the routine
maintenance activities as specified in the BMP manual or reference the page number/table from the
manual that lists the specific maintenance activities that will be performed. The frequency of
maintenance inspections should be consistent with the BMP manual.
Response: Routine maintenance components outlined in Table 8.1 for the Stormwater Management
Devices have been revised as follows: “Stormwater Management Devices will be monitored semi-
annually and maintenance measures will be implemented as needed during the monitoring period.
Measures may include replacing dead vegetative material and removing excess sedimentation from
the forebay of the constructed wetland and its permanent pool, as well as the plunge pools along
Reach T4 during the monitoring period. Should the outlet of the constructed wetland become unstable
during the monitoring period, corrective measures will be implemented to rectify the instability issues
during the monitoring period.”
3. Section 9.2: The NCDMS Monitoring Requirements and Performance Standards for Stream and/or
Wetland Mitigation dated November 7, 2011 stipulates that planted vegetation must average 10
feet in height in each plot at year 7. Please include this requirement in the vegetation performance
standards.
Response: We recognize that average height recommendations are listed as performance standards
for success criteria in Year 5 and 7 in guidelines circulated by the IRT in 2011. It is also true that DMS
released an update to its monitoring guidelines with the understanding that the 2011 IRT document
was an official update to the 2003 document. It was later learned that that was not the case or the
intent of the IRT and therefore an official revision to the 2003 stream mitigation guidelines has not
been produced. Approximate heights by species will be recorded as part an overall assessment of vigor
to determine whether the buffer appears to be on an acceptable trajectory, but given uncertainties in
precipitation, variations in species growth rates and soil heterogeneity the assignment of an arbitrary
blanket average is inadvisable.
4. Section 9.3.2 Wetland Hydrology: The mitigation plan states that performance standards for
wetland hydrology will follow a range from 6-12%, depending on the specific wetland location and
the mitigation activity proposed. Wetland areas receiving credit for restoring or enhancing wetland
hydrology should demonstrate saturation within 12 inches of the soil surface for a minimum 8.5%
of the growing season for Guilford County.
Response: Please see our response to Comment No. 2 (above) under the heading “Ginny Baker/Sue
Homewood, NCDWR, 1 June 2015”.
5. Section 9.0: Please provide performance standards for the constructed wetland (R6) and the
regenerative stormwater control device (T4). In addition, please provide appropriate monitoring
protocols that demonstrate compliance with the proposed performance standards.
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

Response: As discussed in Comment No. 3 (above) under the heading “Todd Bowers, USEPA, 16 July
2015”, the credit ratios for both BMPs were established during a site visit on June 4, 2014. During that
site visit, IRT members and Baker staff agreed that the implementation of the BMPs and associated
enhancement measures would yield a 1.5:1 credit ratio for the valley length of the entire BMP for
which performance criteria was not stipulated. Currently there are no performance criteria for BMPs
and since none were specified by the IRT during this meeting or during following site visits or
subsequent conversation, no performance criteria were developed. See the attached meeting minutes
for reference. Please note that the meeting minutes will also be included in the Appendix of the
Mitigation Plan. Please note that the BMP implementation along Reach T4 was incorrectly labeled as
a regenerative stormwater measure. It should have been listed as a rock lined step pool channel
stormwater control measure. Monitoring text for the stormwater BMPs have been updated in Section
9.4 to reflect this error and the protocols for monitoring have been revised as follows:
“This project includes the implementation of two stormwater BMPs. A constructed wetland, which will
function as a headwater wetland, will be installed along Reach R6, and a rock lined step-pool channel
stormwater control measure will be installed along Reach T4. Both BMPs will be visually monitored
semi-annually for vegetative survival, outlet stability, and storage capacity using photo
documentation during the 7-Year monitoring period. A vegetation plot will also be established along
the planted portion of Reach R6 and will be included as part of the vegetation monitoring outlined in
Section 9.2. Maintenance measures will be implemented during the monitoring period to replace dead
vegetative material and to remove excess sedimentation, as needed, from the forebay of the
constructed wetland and its permanent pool, as well as the plunge pools along Reach T4. Should the
outlet of the constructed wetland become unstable during the 7-Year monitoring period, corrective
measures will be implemented to rectify the instability issues.”
6. Section 10.0: Post-construction profile data should be provided for the entire length of all
Restoration/ Enhancement I stream components.
Response: Table 10.1 has been revised to correctly reflect the post-construction monitoring
requirements for the channel profile parameter as follows: “For Restoration or Enhancement I
activities, a baseline survey (Year 0) will be conducted for the entire length of the channel. Survey will
only be conducted in subsequent monitoring years if the channel is experiencing vertical instability, in
which case survey will be collected within the area of concern.”
7. Section 10.0: The Table 1: Monitoring Requirements chart should include a section for wetland
hydrology monitoring requirements.
Response: Table 10.1 has been updated to include wetland hydrology monitoring requirements as
follows:
Required Parameter Quantity Frequency Notes
X Ground Water
Hydrology
Appropriate to cover
the array of conditions
across the different
wetland types.
Continuously
throughout the
growing season of
Monitoring Years 1 – 7
Ground water gage data will be
collected in each Wetland Type
(1 – 5) to document wetland
hydrology within the area.
8. Section 11.0: The Long-Term Management Plan should include a list of long-term management
activities required for site sustainability, the party responsible for conducting these activities, and
details regarding the funding of these activities. According to the BMP manual, BMPs require
routine inspections on at least a quarterly basis and after each large storm event. Please provide
additional information regarding the annual costs associated with BMP maintenance and repair;
funding for maintenance and repair activities, and the party responsible for these activities. If the
conservation easement holder will assume responsibility for these annual maintenance activities
Michael Baker Engineering, Inc.
797 Haywood Road, Ste. 201 | Asheville, North Carolina 28806
Office: 828.350.1408 | Fax: [phone]

and any associated emergency maintenance and repair costs, please provide written confirmation
from the conservation easement holder. For those areas where no longterm management activities
are anticipated (stream and wetland restoration/enhancement), please include a statement to this
effect in the mitigation plan along with an explanation.
Response: Per Task 3 of RFP #16-005568, the Mitigation Plan is to follow the NCEEP Mitigation Plan
Template – version 2.2 – adopted 8 June 2012. As outlined in this template, the Long-Term
Management Plan Section is to contain language, as written, from one of the three listed examples
that correctly reflects the nature of the responsible party who will hold the conservation easement.
Since the Brown’s Summit project follows the conditions outlined in the first example, the language of
this section has been composed as required. Therefore, no revisions have been made to Section 11.0.
9. Temporary and permanent impacts to existing wetlands and streams must be accounted for in the
PCN and the loss or conversion of those waters must be replaced on-site. Please include a map
depicting the location of all impacts with the PCN.
Response: A temporary and permanent impacts map will be included with the PCN as part of the
permit request package for the project’s 404/401 submittal.

Please do not hesitate to contact me should you have any questions regarding our response submittal.

Sincerely,

Christopher Tomsic, P.E.
Project Manager

Enclosures