HomeMy WebLinkAboutEX03_StreamBufferMitigation
146 N Canal Street, Suite 111 • Seattle, WA 98103 • www.confenv.com
13701 SE May Valley Road
STREAM BUFFER REVISED MITIGATION PLAN
Prepared for:
Elias Wolde
August 2023
EXHIBIT 3
RECEIVED
PLANNING DIVISION
02/02/2024
AVanGordon
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146 N Canal Street, Suite 111 • Seattle, WA 98103 • www.confenv.com
13701 SE May Valley Road STREAM BUFFER REVISED MITIGATION PLAN
Prepared for:
Elias Wolde
13701 SE May Valley Road
Renton, WA 98059
Authored by:
Kerrie McArthur, PWS, CERP, FP-C, and Natalie Dietsch, WPIT
Confluence Environmental Company
August 2023
This report should be cited as:
Confluence (Confluence Environmental Company). 2023. 13701 SE May Valley Road stream buffer revised mitigation plan.
Prepared for Elias Wolde, Renton, Washington, by Confluence, Seattle, Washington.
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TABLE OF CONTENTS
1.0 INTRODUCTION ................................................................................................................................................... 1
2.0 SITE CONDITIONS PRIOR TO UNPERMITTED DEVELOPMENT ...................................................................... 1
3.0 UNPERMITTED DEVELOPMENT AND PROPOSED REMEDY .......................................................................... 5
4.0 IMPACT ASSESSMENT ....................................................................................................................................... 5
5.0 MITIGATION PLAN ............................................................................................................................................... 8
5.1.1 Grading ..................................................................................................................................... 8
5.1.2 Planting Plan ............................................................................................................................. 8
5.2 Schedule ................................................................................................................................................... 8
6.0 COMPLIANCE WITH RMC 4-3-050L.................................................................................................................. 11
7.0 GOALS, OBJECTIVES, PERFORMANCE STANDARDS, AND CONTINGENCY MEASURES ....................... 12
7.1 Plant Survival .......................................................................................................................................... 12
7.1.1 Monitoring Schedule ............................................................................................................... 12
7.1.2 Contingency Measure ............................................................................................................. 12
7.2 Native Species Cover ............................................................................................................................. 13
7.2.1 Monitoring Schedule ............................................................................................................... 13
7.2.2 Contingency Measure ............................................................................................................. 13
7.3 Invasive Species Cover .......................................................................................................................... 13
7.3.1 Monitoring Schedule ............................................................................................................... 13
7.3.2 Contingency Measure ............................................................................................................. 13
7.4 Native Plant Diversity.............................................................................................................................. 13
7.4.1 Monitoring Schedule ............................................................................................................... 13
7.4.2 Contingency Measure ............................................................................................................. 13
8.0 MAINTENANCE .................................................................................................................................................. 14
8.1 Watering ................................................................................................................................................. 14
8.2 Weeding ................................................................................................................................................. 14
8.3 Mowing ................................................................................................................................................... 14
8.4 Mulching ................................................................................................................................................. 14
8.5 Dead Plant Removal ............................................................................................................................... 15
9.0 MONITORING PLAN .......................................................................................................................................... 15
9.1 Year 0 Monitoring ................................................................................................................................... 15
9.1.1 As-Built Map............................................................................................................................ 15
9.1.2 Plots and Photo Points ............................................................................................................ 15
9.1.3 Contingency Baseline Map ..................................................................................................... 16
9.2 Yearly Monitoring .................................................................................................................................... 16
9.2.1 Plant Survival .......................................................................................................................... 16
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9.2.2 Percent Cover ......................................................................................................................... 16
9.2.3 Plant Diversity ......................................................................................................................... 16
9.2.4 Site Photographs .................................................................................................................... 17
10.0 REPORTING ....................................................................................................................................................... 17
10.1 Year 0 Report (As-Built).......................................................................................................................... 17
10.2 Spring Progress Reports ........................................................................................................................ 17
10.3 Annual Progress Reports (Fall) .............................................................................................................. 17
11.0 FINANCIAL SECURITY ...................................................................................................................................... 18
12.0 REFERENCES .................................................................................................................................................... 19
TABLES
Table 1. Planting schedule ............................................................................................................................................. 8
Table 2. Success criteria .............................................................................................................................................. 12
FIGURES
Figure 1. Site vicinity ...................................................................................................................................................... 2
Figure 2. View of lower back yard prior to unpermitted development ............................................................................ 3
Figure 3. Existing critical areas and associated buffers ................................................................................................. 4
Figure 4. View of lower back yard after unpermitted development ................................................................................ 6
Figure 5. View to north of retaining wall (ordinary high water mark is marked with blue pin flags) ................................ 6
Figure 6. Unpermitted patio ............................................................................................................................................ 7
Figure 7. Proposed stream buffer enhancement plan .................................................................................................. 10
APPENDICES
Appendix A Grading Plan ............................................................................................................................................... 1
Appendix B Biologist CV ................................................................................................................................................ 2
Appendix C Bond Worksheet ......................................................................................................................................... 3
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1.0 INTRODUCTION
On March 8, 2022, the property owner of tax parcel 3424059113, located at 13701 SE May Valley
Road, Renton, Washington, received a notice of violation from the City of Renton for
unpermitted land-disturbing activity within a critical area. The notice cited the unpermitted
construction of a patio on the north side of May Creek. The City of Renton requires the
complete removal of the unpermitted improvements (a patio, retaining walls, and stairs) as well
as compensatory mitigation. The purpose of the report is to document impacts from the
development and to propose compensatory mitigation.
On March 28, 2022, Confluence conducted a site investigation to determine the presence and
extent of critical areas on and adjacent to the property. The effort focused on wetlands and
streams. Critical areas such as erosion hazard areas, steep slopes, and landslide hazard areas
were not evaluated in the study. The critical areas identified on the property are described in
detail in the associated critical areas report (Confluence 2022).
Located within the City of Renton, the property is approximately 22,771 square feet (0.52 acre)
and zoned as residential (R-1) (Renton 2022a) (Figure 1). The northern portion of the property is
developed with a single-family residence, a concrete driveway, and a turf lawn and retaining
wall. The southern portion of the property slopes down into a ravine, which May Creek flows
though. A concrete staircase provides access to a recently built paver patio constructed within
the ravine adjacent to the creek.
2.0 SITE CONDITIONS PRIOR TO UNPERMITTED DEVELOPMENT
The property is within the lower portion of the May Valley subarea (GeoEngineers 2008), which
is in the upstream portion of the high-gradient canyon section of May Creek. Within this reach,
from Coal Creek Parkway upstream to a point just above the 143rd Avenue SE bridge, the May
Creek channel is confined. The channel has a moderate gradient with instream and riparian
habitat that has been degraded by erosion and headcutting (GeoEngineers 2008). In general,
most flood events in this area, including the 100-year flood event, are contained within the
stream channel (GeoEngineers 2008).
A critical areas study was conducted on the property. No wetlands were identified, but the
ordinary high water mark of May Creek, a Type F (fish-bearing) stream, was delineated along
the southern portion of the property (Confluence 2022). As described in the report (Confluence
2022), prior to the construction of the flagstone patio and associated retaining wall, the lower
yard area was primarily undeveloped and dominated by herbaceous weeds (Figure 2). Small
retaining walls were present along the western and eastern sides of the property boundary, and
stairs were present on the steep slope from the upper back yard to the lower back yard. A brick
fireplace was also present.
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Figure 1. Site vicinity
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Figure 2. View of lower back yard prior to unpermitted development
According to WDFW (2022a,b), sockeye salmon (Oncorhynchus nerka), coho salmon (O. kisutch),
winter steelhead (O. mykiss), and resident coastal cutthroat trout (O. clarkii clarkii) use May
Creek. Chinook salmon (O. tshawytscha) are known to be present just downstream, west of Coal
Creek Parkway SE (WDFW 2022b). Fish in all stages of life use the portion of May Creek that
runs through the property.
Stream buffer habitat on-site includes native species. Native species in the lower yard were
limited to 2 large black cottonwood (Populus trichocarpa) trees, sword fern (Polystichum munitum)
on the steep slope, and various herbaceous species that appear to be maintained (i.e., mowed).
The steep slope is dominated by English Ivy (Hedera helix), a Class C weed of concern (NWCB
2022). The City of Renton (2022) has mapped steep slopes on the property, north of May Creek
and south of the existing house. The City of Renton (2022) also mapped a portion of the
property as a floodway. However, a Base Flood Elevation Report, prepared by Aspect (2022),
documents that the floodplain is located south of the property and is smaller than what was
mapped by the City of Renton (2022). Figure 3 shows the critical areas and buffers on the
property (Confluence 2022).
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Figure 3. Existing critical areas and associated buffers
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3.0 UNPERMITTED DEVELOPMENT AND PROPOSED REMEDY
Unpermitted development on the site included the following:
Grading of the lower yard (southern portion of the property) to better accommodate a
flagstone patio.
Placement of approximately 2,226 square feet of gravel to level the area.
Placement of 1,082 square feet of flagstone pavers.
Conversion of dirt pathway to paver pathway.
Installation of 2 retaining walls
Maintenance of an existing stairway/path system from the upper yard to the lower yard.
Figures 4, 5, and 6 show the unpermitted development. The unpermitted development occurred
within the 115-foot stream buffer (Renton Municipal Code [RMC] 4-3-50.I.1).
The proposed remedy is complete removal of all unpermitted development and buffer
enhancement. All pavers, the retaining walls, the stairs, and gravel will be removed, the area
will be regraded to minimize erosion, topsoil will be replaced, and native vegetation will be
planted (see Section 5.0 for more details).
4.0 IMPACT ASSESSMENT
Based on the ordinary high water mark delineation (Confluence 2022), no development
occurred waterward of the ordinary high water mark; therefore, only stream buffers were
impacted.
A total of 7,000 square feet of stream buffer was impacted by the unpermitted development.
Prior to the unpermitted development, the stream buffer on the property was very disturbed.
The area was routinely used by the homeowners as a recreational area of the yard, including
use of a fire pit, seating, yard games, etc.
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Figure 4. View of lower back yard after unpermitted development
Figure 5. View to north of retaining wall (ordinary high water mark is marked with blue pin flags)
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Figure 6. Unpermitted patio
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5.0 MITIGATION PLAN
The proposed mitigation is on-site buffer enhancement, which will occur after the existing
pavers and gravel are removed.
On-site, 7,000 square feet of stream buffer, previously lawn and English ivy, will be enhanced
with native trees, shrubs, and herbaceous plants. This will create a multi-layered vegetation
community, which will provide higher quality habitat functions than pre-existing conditions
(i.e., lawn with 2 mature black cottonwood trees). The addition of conifers will aid in the
successional transition from the currently deciduous forested buffer to a coniferous forested
buffer.
As discussed with the City of Renton, once the stairs are removed, a dirt path will be allowed to
remain to provide access to the mitigation area.
5.1.1 Grading
The existing flagstone, retaining walls, and gravel will be removed and replaced with topsoil.
For additional detail about grading, refer to the grading plan in Appendix A.
5.1.2 Planting Plan
The planting schedule shown in Table 1 is proposed for the 7,000-square-foot buffer
enhancement area (Figure 7). This enhancement will provide improved buffer function as
compared to pre-development conditions. The specific locations of the plants will be
determined in the field by the contractor and reported in the Year 0 report.
5.2 Schedule
Removal of the paver patio, gravel, stairs, and retaining walls; grading; and topsoil installation
will occur in the summer and fall, following approval of this mitigation plan by regulating
agencies. Planting will occur in the fall.
Table 1. Planting schedule
Common Name Scientific Name Container Size Spacing (feet OC) Quantity1 Habitat Function2
Trees
Western red-
cedar
Thuja plicata 2 gallon 9 11 Snags are valuable habitat for cavity nesting birds.
Western red-cedar provides cover for several
wildlife species. The seeds, twigs, and foliage are
eaten by wildlife. Small mammals use cavities in
western red-cedars for dens.
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Common Name Scientific Name Container Size Spacing (feet OC) Quantity1 Habitat Function2
Western hemlock Tsuga
heterophylla
2 gallon 9 11 Preferred nesting tree for many birds. Western
hemlock provides cover for several wildlife species.
Bark is eaten by many small mammals, and the
foliage and twigs are eaten by deer and elk.
Douglas-fir Pseudotsuga
menziesii
2 gallon 9 11 Snags are valuable habitat for cavity nesting birds.
Douglas-fir provides cover for several wildlife
species. The seeds, twigs, and foliage are eaten by
wildlife. Small mammals use cavities in Douglas-firs
for dens.
Pacific dogwood Cornus nuttallii 2 gallon 9 11 Deer and elk eat the leaves. Small mammals eat
the fruit.
Shrubs
Salal Gaultheria
shallon
2 gallon 6 32 Leaves eaten by deer and elk. Fruits are eaten by
small mammals and birds.
Baldhip rose Rosa
gymnocarpa
2 gallon 6 32 Fruits are eaten by various herbivores and upland
game birds. Leaves and twigs are eaten by
browsers. Provides nesting and habitat for song
birds.
Red-flowering
currant
Ribes
sanguineum
2 gallon 6 32 Flowers attract birds and insects. Foliage is eaten
by butterflies and the fruits are eaten by many birds
and small mammals.
Ocean-spray Holodiscus
discolor
2 gallon 6 32 Flowers attract birds and butterflies.
Evergreen
huckleberry
Vaccinium
ovatum
2 gallon 6 32 Fruits are eaten by songbirds and mammals. The
foliage is eaten by deer, elk, rabbits, and grouse.
Flowers attract hummingbirds, butterflies, and other
pollinators.
Herbaceous
Bleeding heart Dicentra
formosa
4-inch
pots
4 52 (in clumps
of 3-5)
Flowers attract birds and insects.
Sword fern Polystichum
munitum
4-inch pot 4 52 Great cover for insects and small birds.
Western
starflower
Trientalis
latifolia
4-inch pot 4 52 (in clumps
of 3-5)
Flowers attract birds and insects.
Meadow Seed
Mix3
— 23 lbs per
acre
N/A 1.05 lbs Meadow seed mix attract birds and insects.
TOTAL 360
1 Quantities are based on 7,000 square feet of total planting area and plants installed based on triangular pattern.
2 Sources: Native Plants PNW 2023, Cooke 1997, Stuart and Sawyer 2001, USDA 2008, WNPS 2019, Stark 2022, NRCS 2022
3 Source: Renton 2022b
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Figure 7. Proposed stream buffer enhancement plan
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6.0 COMPLIANCE WITH RMC 4-3-050L
RMC 4-3-050L describes the criteria for a mitigation plan to be approved. Each criterion is listed
below (in italics) followed by how the proposed mitigation plan meets the criterion.
i. Demonstrate sufficient scientific expertise, the supervisory capability, and the financial resources to
carry out the mitigation project; and
The proposed mitigation plan was developed by Kerrie McArthur, who has 28 years of
experience in developing and monitoring mitigation plans. Kerrie McArthur’s CV is in
Appendix B. She used best available science and her expertise to develop a scientifically sound
mitigation plan. Thus, the plan was developed using scientific expertise. A qualified
professional, like Kerrie McArthur, will be contracted by the property owner to oversee the
construction of the on-site portion of the mitigation plan (i.e., buffer enhancement). Thus, the
plan will have the supervisory capability to ensure it is constructed properly. A financial
guarantee is proposed (see Section 11.0). Thus, this criterion is met.
ii. Demonstrate the capability for monitoring the site and making corrections during the monitoring
period if the mitigation project fails to meet projected goals; and
The proposed mitigation plan includes performance standards and contingency measures to
ensure that the mitigation meets the projected goals. A qualified professional, like Kerrie
McArthur, will oversee monitoring and corrective actions. Kerrie’s McArthur’s 28 years of
experience demonstrates than she has the capability to monitor the site and make corrections
during the monitoring period to ensure success of the project. Thus, this criterion is met.
iii. Protect and manage, or provide for the protection and management, of the mitigation area to avoid further
development or degradation and to provide for long-term environmental health of the mitigation area; and
The mitigation area will be recorded on the title, thus protecting the buffer and avoiding future
development or degradation. Thus, this criterion is met.
iv. Provide for project monitoring and allow City inspections; and
The property owner will allow for project monitoring and City inspections as required. Thus,
this criterion is met.
v. Avoid mitigation proposals that would result in additional future mitigation or regulatory
requirements for adjacent or abutting properties.
The mitigation plan would not require additional future mitigation or regulatory requirements
on adjacent properties. Thus, this criterion is met.
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7.0 GOALS, OBJECTIVES, PERFORMANCE STANDARDS, AND CONTINGENCY
MEASURES
The goal of the mitigation plan is to restore stream buffer functions impacted from the
construction of the patio. To achieve this goal, the objective is to enhance 3,308 square feet of
stream buffer by installing a mix of native trees, shrubs, and herbaceous plants. To ensure the
goal and objective of the mitigation plan are met, the following performance standards and
contingency measures are proposed. The success criteria for the performance standards are
summarized in Table 2.
Table 2. Success criteria
Performance Standard
Success Criteria
Year 0 Year 1 Year 2 Year 3 Year 4 Year 5
Plant Survival (%) NC 100% 80% NC NC NC
Native Species (% cover) NC NC NC 50% NC 80%
Invasive Species* (% cover) NC <10% <10% <10% <10% <10%
Native Plant Diversity NC NC NC NC NC 3 native species comprising ≥10% cover
each
and
2 out of 3 vegetative layers (tree, shrub, or
groundcover) provide ≥20% cover
* Source: King County NWCB 2022 (or latest version)
NC No criterion; may be used as baseline information.
7.1 Plant Survival
7.1.1 Monitoring Schedule
Planted vegetation and natural recruits will be monitored for survival for 2 years (Year 1 and
Year 2). Monitoring will not occur after Year 2 because it is expected that plant growth and the
amount of natural recruits will make identifying planted vegetation extremely difficult.
7.1.2 Contingency Measure
Plant survival could be negatively affected by improper installation, diseased or infested plants,
inadequate watering, or extreme weather. If more than 25% of installed plants die in a single
year, the cause of the high losses will be investigated and corrected before dead plants are
replaced. Dead plant material will only be removed after that year’s scheduled monitoring. If
less than 80 percent of the total plants installed have survived during the Year 2 monitoring,
additional plants will be installed to bring the planting schedule back into original
specifications. It is the expectation that all installed plants be monitored for survival for 2 years,
so if plants are installed after Year 0, those plants will be monitored for survival for 2
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consecutive years, which may require monitoring to occur after Year 2. For example, if
additional plants are installed during Year 2 as a contingency measure, those plants would be
monitored for survival during Year 3 and Year 4 monitoring events.
7.2 Native Species Cover
7.2.1 Monitoring Schedule
Planted vegetation and natural recruits will also be monitored for percent cover for 2 years
(Year 3 and Year 5).
7.2.2 Contingency Measure
Native plant growth, as determined by percent cover, could be negatively affected by improper
installation, diseased or infested plants, inadequate watering, or extreme weather. If the native
species success criterion is not met, the cause will be investigated and corrected. Correction
measures may include increased watering, soil amendments, fertilizing, or revision of planting
palate and additional plantings.
7.3 Invasive Species Cover
7.3.1 Monitoring Schedule
The percent cover of invasive species will be monitored for 5 years (Year 1, Year 2, Year 3, Year
4, and Year 5).
7.3.2 Contingency Measure
Dominance by invasive species could result from the disturbance of the soil, a high mortality
rate of the native planted vegetation, or colonization by windborne seeds. To reduce
colonization by invasive species, a site maintenance plan is described in Section 8.0. If more
than 25% of area is covered by invasive species, the cause of infestation will be investigated and
corrective actions will be taken before weeds are removed. Contingency measures could include
increasing the frequency of weeding until native vegetation can grow and dominate the area or
increasing the density of native vegetation with additional plantings.
7.4 Native Plant Diversity
7.4.1 Monitoring Schedule
Planted vegetation and natural recruits will also be monitored for diversity for 1 year (Year 5).
7.4.2 Contingency Measure
Plant diversity, as determined by the number of native species within the enhancement area,
could be negatively affected by improper installation, diseased or infested plants, inadequate
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watering, or extreme weather. If the plant diversity success criteria are not met, the cause will
be investigated and corrected. Correction measures may include a revision of the planting
schedule and additional plantings.
8.0 MAINTENANCE
Maintenance activities in the mitigation area will change throughout the duration of the
monitoring and maintenance period. These activities will be concentrated immediately after
installation and continue through the first and second years post-installation or longer if
necessary to ensure performance standard success criteria are met.
8.1 Watering
Watering may be necessary depending on the date of planting and the amount of rainfall that
year. Since plant installation is planned to occur during fall, watering is not scheduled until the
following summer, other than at the time of plant installation. Monthly watering may be
necessary during the first, second, and third summers after plant installation to assist survival
and establishment of plantings.
How watering occurs will be determined by the contractor overseeing the maintenance of the
enhancement area. For example, watering could occur via water truck or the installation of an
irrigation system.
8.2 Weeding
Weeding around trees and shrubs will be important during the growing seasons to ensure
establishment and prevent stress to the plants from competition for resources. Weeding will
occur twice a month during the early growing season (typically between March and July) and
late growing season (typically September through October). During the remainder of the year
weeding will occur monthly. All invasive species will be weeded. This schedule of weeding will
occur until the plants have established themselves and begun to out-compete the invasive
species.
Weed whacking will be allowed around plantings. No herbicide will be allowed.
8.3 Mowing
Mowing will not be allowed in the enhancement area.
8.4 Mulching
Mulching may occur around shrub and tree plantings to help retain water. Mulch around
plantings will be no thicker than 4 inches. Mulch will be placed when plants are installed, and
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additional mulch may be placed as needed throughout the monitoring period. Mulch will be
placed so the plant root systems will not come in contact with the mulch.
8.5 Dead Plant Removal
Dead plant material will only be removed after scheduled monitoring. This will allow for the
accurate assessment of planting success needed for the monitoring program. Replacement
planting will be detailed in the applicable report developed during the monitoring program.
This will include species recommendations to maintain the desired diversity in the plant
communities of the buffer area.
9.0 MONITORING PLAN
A monitoring period of 5 years is proposed to ensure that the vegetated wetland buffer achieves
the goals and objectives of the mitigation plan. A Year 0 (or “as-built” report) will serve as the
baseline for future monitoring events. This section describes the monitoring methods that will
be used to determine if the performance standard success criteria are met.
9.1 Year 0 Monitoring
Data collected in Year 0 will provide the baseline for the success criteria for Years 1 through 5
monitoring. There are no success criteria associated with Year 0.
9.1.1 As-Built Map
Confluence will use a global positioning system (GPS) to record the location of each installed
plant. An as-built map of installed plants will then be used in subsequent monitoring events to
determine plant survival.
9.1.2 Plots and Photo Points
Up to 4 10-foot radius plots will be established within the enhancement area. The actual number
and locations of the plots will be determined in the field after plant installation. Coordinates for
the locations of the center point of each plot will be recorded using GPS and reported in the
Year 0 Report.
In each circular plot, the percent cover of each species, including bare ground, will be estimated
and recorded.
Permanent photo points will be established at the center of each plot to document the site over
time. At each of the photo points, a fixed-lens digital camera will be used to take photographs,
either a panoramic photo or one at every 90 degrees of the compass.
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9.1.3 Contingency Baseline Map
Should Confluence determine that any portion of the enhancement area needs to be replanted, a
survey will be conducted after the replanting has been completed. This survey will then become
the baseline for subsequent monitoring surveys. For example, if the survival success criterion is
not met in Year 2 and the ecologist determines that additional trees or shrubs need to be
planted, a survey would be conducted after the addition of new plants. This survey would then
provide the baseline for remaining monitoring events.
9.2 Yearly Monitoring
Monitoring will occur in both the spring and the fall, but detailed monitoring will only occur in
the fall. Spring monitoring will occur after deciduous plants have flowered or leafed out, and
fall monitoring will occur before deciduous leaves have dropped for easier identification.
During spring monitoring events, Confluence biologists will conduct a short, qualitative,
meander survey to take photos and assess progress toward annual success critieria. The goal of
the spring monitoring will be early identification of any potential issues that would prevent the
site from meeting the success criteria during the fall monitoring for that year. Confluence will
note overall plant health, invasive species colonization, additional maintenance needs, and any
other emergent needs.
Following are the methods to be used during fall monitoring. Interim and final success will be
defined as meeting the success criteria for the performance standards shown in Table 2.
9.2.1 Plant Survival
Plant survival will be recorded within the mitigation area by comparing the number and species
of plants recorded on the as-built drawings to site conditions at the time of monitoring. The
percent survival is calculated by dividing the number of plants (by species) identified as alive
during the monitoring event by the number of plants (by species) identified on the as-built plan
provided in the Year 0 report.
It is the expectation that all installed plants be monitored for survival for 2 years, so if plants are
installed after Year 0, then those plants will be monitored for survival for 2 consecutive years,
which may require monitoring to occur after Year 2.
9.2.2 Percent Cover
In each circular plot, the percent cover of native and invasive species and of bare ground will be
estimated and recorded.
9.2.3 Plant Diversity
Plant diversity will be calculated by determining whether at least 3 native plant species, each
making up a minimum of 10% coverage, are present within the mitigation area and whether at
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least 2 vegetative layers each provide at least 20% cover. To determine percent cover of
vegetative layers, each plant species will be categorized by vegetative layer (tree, shrub, or
groundcover), and the percent cover of each vegetative layer will be determined by summing
the percent cover of each species within a vegetative layer. Existing, installed, and naturally
recruited native plant species will all be included in calculating plant diversity.
9.2.4 Site Photographs
At each of the photo points, a fixed-lens digital camera will be used to take photographs, either
a panoramic photo or one at every 90 degrees of the compass.
10.0 REPORTING
Confluence will prepare 6 reports over a 5-year period, including 1 Year 0 report and 5 annual
progress reports.
10.1 Year 0 Report (As-Built)
The Year 0 report and as-built drawing will be completed within approximately 30 days after
buffer enhancement site construction is completed. One copy of the report will be provided to
the City. The following will be included in the report:
Actual planting schedule (density, container size)
Coordinates of transect and photo point locations
Locations of transects and photo points depicted on a figure
Locations of installed plants depicted on a figure
Description of changes from original site design
10.2 Spring Progress Reports
For each spring monitoring event, Confluence will prepare a short letter report documenting
the findings of the meander survey. Confluence will discuss overall plant health, invasive
species colonization, additional maintenance needs, and any other emergent needs in the letter
report.
10.3 Annual Progress Reports (Fall)
For each fall monitoring event, Confluence will prepare a report. One copy of each report will
be provided to the City. The following will be included in each report:
Date of survey
A narrative description of methods and contingency measures taken
Identification of planted and naturally-recruited trees and shrubs
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Data tables
Interpretation of results
Recommendations for additional plantings, if needed
Recommendations for additional maintenance, if needed
Color photos
All annual progress reports will be submitted within approximately 60 days of conducting the
monitoring survey. Monitoring reports will be submitted for Years 1, 2, 3, 4, and 5 documenting
success of meeting the success criteria listed in Table 2.
11.0 FINANCIAL SECURITY
RMC 4.3.050L.2 states that a performance or maintenance security will be required in the
amount and form as the Planning Official deems necessary to assure that all work or actions are
satisfactorily completed and maintained in accordance with the approved plans, specifications,
and permit or approval requirements. Per RMC4.3.050L.2, the King County Critical Areas Bond
worksheet was used to determine the amount of required financial security. This Critical Areas
Mitigation Bond worksheet is attached in Appendix C.
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12.0 REFERENCES
Aspect (Aspect Consulting). 2022. Base flood elevation study. Prepared for Elias Wolde, Renton,
Washington, by Aspect, Seattle, Washington.
Cooke, S. 1997. A field guide to the common wetland plants for western Washington and
northwestern Oregon. Seattle Audubon Society and Washington Native Plant Society.
Confluence (Confluence Environmental Company). 2022. 13701 SE May Valley Road critical
areas study. Prepared for Elias Wolde, Renton, Washington, by Confluence, Seattle,
Washington.
GeoEngineers. 2008. Final draft May Creek drainage and restoration plan. Prepared for King
County, Seattle, Washington, and Mid-Puget Sound Fisheries Enhancement Group, Seattle,
Washington. Available at: https://your.kingcounty.gov/dnrp/library/water-and-
land/watersheds/cedar-river-lake-wa/may-creek/may-creek-drainage-restoration-plan.pdf
(accessed August 5, 2022).
King County NWCB (Noxious Weed Control Board). 2022. English ivy identification and
control. King County Noxious Weed Control Board, Seattle Washington. Available at:
https://kingcounty.gov/services/environment/animals-and-plants/noxious-weeds/weed-
identification/english-ivy.aspx (accessed August 4, 2022).
Native Plants PNW (Pacific Northwest). 2023. An encyclopedia of the cultural and natural
history of Northwest native plants. Available at: https://nativeplantspnw.com/the-native-
plants/ (accessed on January 15, 2023).
NRCS (Natural Resources Conservation Service). 2022. The PLANTS database [online database].
U.S. Department of Agriculture, NRCS, National Plant Data Team, Greensboro, North
Carolina. Available at: https://plants.sc.egov.usda.gov/java/ (accessed on November 8, 2022).
Renton (City of Renton). 2022a. City of Renton – COR Maps. Available at:
https://maps.rentonwa.gov/Html5viewer/Index.html?viewer=cormaps (accessed on May 5,
2022).
Renton (City of Renton). 2022b. City of Renton surface water design manual, Appendix D.
Available at: https://cdnsm5-
hosted.civiclive.com/UserFiles/Servers/Server_7922657/File/City%20Hall/Public%20Works/
Utility%20Systems/Surface%20Water%20Design%20Standards/2022%20SWDM%20Appendi
x%20D.pdf (accessed August 7, 2023).
Stark, E. 2022. Pacific Northwest native plant profiles [online resource]. Available at:
http://www.realgardensgrownatives.com/?cat=392 (Accessed January 15, 2023).
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Stuart, J.D., and J.O. Sawyer. 2001. Trees and shrubs of California. University of California
Press, Berkley, California.
USDA (U.S. Department of Agriculture). 2008. The woody plant seed manual. Agriculture
Handbook 727. Available at: https://www.fs.usda.gov/nsl/nsl_wpsm.html (accessed January
15, 2023).
WDFW (Washington Department of Fish and Wildlife). 2022a. PHS on the web interactive
mapping [online database]. Washington Department of Fish and Wildlife Habitat Program,
Olympia, Washington. Available at: https://geodataservices.wdfw.wa.gov/hp/phs/ (accessed
on May 5, 2022).
WDFW (Washington Department of Fish and Wildlife). 2022b. SalmonScape interactive
mapping [online database]. Washington Department of Fish and Wildlife, Olympia,
Washington. Available at: http://apps.wdfw.wa.gov/salmonscape/map.html (accessed on
May 5, 2022).
WNPS (Washington Native Plant Society). 2019. Native plants for western Washington gardens
and restoration projects [online resource]. Available at:
https://www.wnps.org/landscaping/herbarium/index.html (Accessed on January 15, 2023).
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Appendix A
Grading Plan
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Appendix B
Biologist CV
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kerrie.mcarthur@confenv.com
KERRIE McARTHUR, PWS, CERP
Managing Senior Biologist
EDUCATION
B.S., Biological Oceanography, Minor in
Fisheries, University of Washington, Seattle,
WA, 1995
CERTIFICATIONS
Professional Wetland Scientist, #2655, Society
of Wetland Scientists
Certified Ecological Restoration Practitioner,
#0187, Society for Ecological Restoration
Certified Fisheries Professional, American
Fisheries Society, No. 2841
EXPERTISE
Biological Assessments/Evaluations
Wetland, Stream, OHWM Delineation
Mitigation Planning, Design, Monitoring
Environmental Permitting/Agency Coordination
Plant, Fish, and Wildlife Surveys
AFFILIATIONS
Society of Wetland Scientists, 2008-present
Society for Ecological Restoration, 2012 –
present, Vice President, July 2022-present
Kerrie McArthur has 28 years of wide-ranging experience as a natural resources
professional. Kerrie specializes in assessing impacts to fish and wetlands, regulatory
permitting and associated mitigation, and restoration/mitigation design. She conducts
wetland reconnaissance and delineations, aquatic and terrestrial habitat evaluation,
wildlife research projects, biological assessments of threatened and endangered species,
fisheries surveys, functional assessment of aquatic ecosystems, water quality monitoring,
stream-channel characterization, and mitigation monitoring. Kerrie has managed
hundreds of projects to permit wetland impacts from a wide variety of projects, ranging
from small, single-family developments to large industrial proposals. She has developed
mitigation plans and restoration designs, integrating mitigation actions into proposed
development actions to facilitate permit approvals. Kerrie also provides construction
oversight to ensure proper design implementation and to take advantage of field
engineering opportunities.
Representative Projects
Critical Area Studies, Various Private Developers, Western Washington. Kerrie
managed and conducted numerous critical area studies for clients in Snohomish, King,
and Pierce counties, delineating wetlands and ordinary high water marks (OHWMs), and
assisting with permitting. For each project, Kerrie evaluates mitigation opportunities,
constraints, and feasibility for impacts using a watershed approach, including evaluating
the use of mitigation banks. Depending on the project location and impact, mitigation
included on-site mitigation and mitigation banks or a combination of both. Clients include:
Artoush Fanaiyan, Kirkland, WA
S&G West Continent LLC, Snohomish County, WA
DA Homes, LLC, Snohomish County, WA
Alex Petrov, Snohomish, WA
Lake Washington Partners, Bellevue, WA
Investus LLC, Snohomish County, WA
John Trang, Burien, WA
Axiom Design + Build, Seattle, WA
On-Call Critical Area Report Review Services, City of Puyallup, WA. Project Manager.
Since 2019, Kerrie has provided peer review of critical area reports associated with
development proposals and land use issues. Work includes conducting site visits and
reviewing reports for compliance with Puyallup Municipal Code and the Shoreline Master
Program and for conformance with local, state, and federal requirements. Kerrie has
reviewed a variety of critical area reports for over a dozen development projects under
this contract.
Port Susan Trail Wetland Delineation Study, City of Stanwood, Stanwood, WA. Senior Biologist. This project proposes to
construct a nonmotorized path between a park-and-ride facility and the proposed Hamilton Landing Park project. To support the 30%
design, Kerrie conducted critical areas studies at 3 study areas in Stanwood. Wetlands were identified, delineated per U.S. Army Corps
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KERRIE McARTHUR, PWS, CERP
Managing Senior Biologist
of Engineers (Corps) methodology, and rated using the Washington State Department of Ecology (Ecology) rating system. Work
included using soil probes to determine the wetland boundary between test plots and to determine if an area was wetland or upland.
Lummi Island Quarry Reclamation and Restoration, Lummi Island Heritage Trust, Lummi Island, WA. Senior Biologist. The
Trust plans reclamation activities on the Aiston Preserve, a 105-acre forested site with 4,000 linear feet of shoreline that was
impacted by previous mining operations. Kerrie’s work on the project included site reconnaissance, OHWM delineation, and
identification of wetland restoration opportunities.
Frederickson Industrial Park Development Permitting, Sierra Pacific Industries (SPI), Frederickson, WA. Project
Manager/Senior Biologist. SPI acquired properties in the Frederickson, Washington, urban growth area to develop an industrial
park, including a lumber manufacturing facility. Kerrie led a team to provide permitting assistance for the construction of a new
lumber-manufacturing facility and cogeneration plant and industrial pad ready lots. Kerrie managed and conducted wetland
delineations and field surveys on this 290-acre site to evaluate fish and wildlife habitat, Oregon White Oak stands, and identify
mitigation opportunities. She prepared a critical areas study, JARPA, and detailed mitigation plan. Mitigation includes the
rehabilitation and creation of 25 acres of wetland and wetland buffer and planting Oregon white oaks. Kerrie coordinated submittal
of permit application packages as well as the Cultural Resources survey. She assisted the client with agency negotiations and
permit applications, including an Ecology Section 401 permit and county grading permits. In 2019, Kerrie oversaw the construction
of and planting of 88,000 plants at the 25-acre wetland mitigation site. Currently, Kerrie is managing and conducting mitigation
monitoring.
Ovenell Farm Park Master Planning, Community Development Department, City of Stanwood, WA. Senior Biologist. Kerrie
conducted a critical area study, including wetland and OHWM delineation, on the City’s “Ovenell Farms” property, which the City is
converting to a park and historical site. She co-wrote a critical area study report that met the requirements of the Stanwood Municipal
Code, Ecology, and the Corps. The report included the results of the wetland and OHWM delineations and wetland ratings, and
summarized the relevant regulations governing the delineated wetlands, ditches, and the Stillaguamish River on or adjacent to the
site. Kerrie also delivered a summary of the relevant permits potentially needed for the proposed park and discussed the potential
mitigation opportunities on the site. In a related subsequent project, assisted with an update to the City of Stanwood Shoreline
Master Plan for the Ovenell property and Hamilton properties to address changed uses of these properties to parks. The proposed
park features have the potential to impact existing wetlands and streams/river as well as wetland, stream, or shoreline buffers. Kerrie
conducted a site reconnaissance, developed conceptual park designs and associated mitigation concepts that are appropriate to
achieve regulatory approvals, developed a summary of Shoreline Master Plan uses and polices that may need to be revised on order
to allow such uses, and developed a preliminary cost estimate to construct the park features. The work will focus on the 200-foot
shoreline zone as measured from the Stillaguamish River OHWM. The update was approved in 2019.
Watercourse Evaluation and Wetland Delineation at 4803 Forest Avenue SE, Laurie Cropp, Mercer Island, WA. Project
Manager. Kerrie evaluated a mapped watercourse in 2015 on property proposed for development of a single-family home. Work
involved desktop analysis, site visit, analysis of surface water runoff using the Western Washington Hydrologic Model 2012, and
report preparation. During the evaluation, no watercourse, as defined by Mercer Island City Code (MICC), was identified. In 2017,
she investigated possible presence of a wetland and wrote recommendations for development in accordance with MICC 19.07.070
and 19.07.080. The wetland was determined to have developed through an artificial hydrology source. Kerrie conducted an
evaluation on the changes in impervious surfaces upslope of the wetland that was source of wetland hydrology. Despite the
artificial source of hydrology, the City of Mercer Island claims jurisdiction over the wetland. Because the development would impact
the on-site wetland buffer, Kerrie developed a mitigation plan to compensate for unavoidable impacts.
Kenmore Property Critical Areas Study, Tatyana Avanesova, Kenmore, WA. Project Manager. Kerrie conducted a critical
areas study for property owner wishing to build single-family home. She delineated the OHWM and conducted a fish passage
evaluation for a culvert. Work also included coordinating with the City of Kenmore to develop an off-site mitigation strategy and
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KERRIE McARTHUR, PWS, CERP
Managing Senior Biologist
designing the mitigation plan, which involved preparing a cost estimate for the construction, maintenance, and monitoring of
wetland and stream buffer restoration that would occur off-site but within the same sub-basin.
20-Acre Development, Peter Lomakin, Snohomish, WA. Project Manager/Senior Biologist. The property owner proposed to
subdivide a 20-acre parcel and construct four single-family residences. Kerrie assisted the property owner in lifting development
moratorium associated with a Class III forestry permit. She conducted a wet land delineation following the Corps Wetlands
Delineation Manual (1987) and the local Interim Regional Supplement (Corps 2010). Wetland functions were evaluated using the
Western Washington Wetland Rating System (Hruby 2014) for a proposed church and bible college. Kerrie delineated the wetland
edge using flagging and used GPS to locate the wetland boundaries. Mitigation included purchasing mitigation bank credits and
wetland buffer enhancement.
Brookside Vegetation Management and Sediment Maintenance, Lake Washington Partners, Bellevue, WA. Project
Manager. Kerrie developed a site-wide vegetation management plan to address routine vegetation maintenance and management
of invasive species. She prepared a sediment management plan to address sediment deposition that was occurring near the
culvert, reducing the culvert’s capacity to pass water. In addition, Kerrie prepared yearly stream buffer vegetation maintenance
summary reports to the City of Bellevue as part of the vegetation management permit requirements.
River Home Mobile Estates Permitting Assistance, HCA Management Company, Auburn, WA. Project Manager. Kerrie
provided permitting assistance for proposed mobile home park expansion, along the Green River. The property was located
behind an existing levee but still within the floodplain of the Green River. She conducted wetland delineation following the Corps
Wetlands Delineation Manual (1987) and the local Regional Supplement (Corps 2010). Wetland functions were evaluated using
the Western Washington Wetland Rating System (Hruby 2004). She also prepared a wetland delineation report, Floodplain Habitat
Assessment, SEPA checklist, floodplain development permit application, and zoning change request.
Permitting for Port of Tacoma Properties Development, SPI, Spanaway, WA. Project Manager/Senior Biologist. Kerrie
managed a multidisciplinary team to provide permitting assistance for the construction of industrial, pads ready lots. She managed
and conducted wetland delineations and field surveys on this 45-acre site to evaluate fish and wildlife habitat, Oregon White Oaks,
and identify mitigation opportunities. The work included characterizing difficult soils. Kerrie prepared a critical areas study and
detailed mitigation plan. Mitigation includes planting Oregon White Oaks as replacement for those to be removed during
development. She also prepared SEPA checklist and County permitting package, including a fish and wildlife habit variance
request; coordinated submittal of permit application packages; and provided testimony during hearing examination.
Log Boom and Squire’s Landing Park Improvements, City of Kenmore, WA. Senior Biologist. Kerrie conducted delineations of
wetlands and OHWMs, assessed wildlife habitat, and prepared associated technical reports, and is contributed to permitting and
mitigation planning. Proposed improvements at the Log Boom and Squire's Landing parks include improved trails, hand-carried
boat access, and dock replacement. This project has involved extensive coordination with entities including the Corps, Ecology,
Washington Department of Fish and Wildlife, Muckleshoot Indian Tribe, and area nonprofit groups.
Technical Training Center Hamm Creek Mitigation Planning, Seattle City Light, Seattle, WA. Senior Biologist. Project
involved rehabilitation of historic intertidal marsh and stream habitats to provide integrated salmonid habitat with Hamm Creek and
the Duwamish River. Kerrie evaluated feasibility and cost effectiveness of alternative restoration strategies. She contributed to
development of wetland mitigation conceptual design as part of overall site development plan for the Seattle City Light Technical
Training Center. Identified plants species appropriate for carrying levels of inundation and salinity
Lake Roesiger Park Shelter Environmental Studies, Snohomish County Parks and Recreation, Snohomish, WA. Senior
Biologist. Kerrie c onducted a wetland delineation, and lake and stream OHWM determinations at Lake Roesiger County Park for
proposed construction of a picnic shelter on an existing gravel parking area along the shoreline of Lake Roesiger. Work included a
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KERRIE McARTHUR, PWS, CERP
Managing Senior Biologist
site investigation to evaluate the potential presence of regulated wetlands and fish and wildlife habitat conservation areas on the
subject properties.
Arlington Road Maintenance Facility Critical Area Study, Snohomish County Public Works, Arlington, WA. Senior Biologist.
Kerrie led 1 of 2 teams conducting a critical area study for 4 properties being evaluated for proposed construction of the Arlington
Road Maintenance and Fleet Management Facility. The work involved a site investigation to evaluate the potential presence of
regulated wetlands and fish and wildlife habitat conservation areas on the subject properties, mapping critical areas, and
documenting their regulatory classifications in a critical area study.
Ash Way Roadway Improvement Snohomish County Public Works, Lynnwood, WA. Senior Biologist. Kerrie led 1 of 2 field
crews to conduct a wetland delineation along 2.2. miles of Ash Way right of way. This project proposes to improve 2.2 miles of Ash
Way between 18th Avenue W and the intersection of Gibson Road and Admiralty Way. Preliminary investigations revealed the
likely presence of wetlands and streams. Work under this on-call task order is to delineate critical areas, and document their
regulatory classifications and mitigation needs in a report. Kerrie completed a wetland delineation per the Corps Wetlands
Delineation Manual (1987) and the local Regional Supplement (Corps 2010), and identified and delineated the OHWM and
bankfull width of streams in accordance with WAC 222-16-010 and Determining the Ordinary High Water Mark on Streams in
Washington State (Ecology Publication # 16-06-029). Wetlands were rated using the Washington State Wetland Rating System for
Western Washington (Ecology Publication #14-06-029). This included a variety of data-collection points from the field effort. A sub-
meter GPS was used to collect points of the wetland/stream features and other data points, and flags were placed during the field
effort.
14th Avenue W Roadway Extension Critical Area Study and Biological Assessment, Snohomish County Public Works,
Bothell, WA. Senior Biologist. Kerrie led 1 of 2 field crews conducting delineation of critical areas and will document their
regulatory classification in a critical area study. Delineated wetlands and OHWM of streams using Corps Wetlands Delineation
Manual (1987) and the local Regional Supplement, and identified and delineated the OHWM and bankfull width of streams in
accordance with WAC 222-16-010 and Determining the Ordinary High Water Mark on Streams in Washington State. Future work
includes preparing a draft and final biological assessment to document potential effects of the project on listed and proposed,
threatened or endangered species and their critical habitats to comply with ESA Section 7. The biological assessment will analyze
the project, identify temporary or long-term effects of project elements to listed species and make an effects determination.
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Appendix C
Bond Worksheet
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Date: 8/7/23 Prepared by:
Project Number: _________________
Applicant:Phone: (206) 790-4136
PLANT MATERIALS (includes labor cost
for plant installation)
Type Unit Price Unit Quantity Cost
PLANTS: Potted, 4" diameter, medium $5.00 Each 156.00 $ 780.00
PLANTS: Container, 1 gallon, medium soil $11.50 Each $ -
PLANTS: Container, 2 gallon, medium soil $20.00 Each 204.00 $ 4,080.00
PLANTS: Container, 5 gallon, medium soil $36.00 Each $ -
PLANTS: Seeding, by hand $0.50 SY 222.00 $ 111.00
PLANTS: Slips (willow, red-osier)$2.00 Each $ -
PLANTS: Stakes (willow)$2.00 Each $ -
PLANTS: Stakes (willow)$2.00 Each $ -
PLANTS: Flats/plugs $2.00 Each $ -
TOTAL $ 4,971.00
Type Unit Price Unit Cost
Topsoil delivered and spread $37.88 CY 61.00 $ 2,310.68
Removal of gravel, medium, to 6" depth $1.57 CY 61.00 $ 95.77
Labor: Consultant, supervising $55.00 HR 8.00 $ 440.00
Irrigation - temporary $3,000.00 Acre 0.05 $ 150.00
TOTAL $ 2,996.45
EROSION CONTROL
ITEMS Unit Cost Unit Cost
Excavation, bulk $4.00 CY 1654.00 $ 6,616.00
Fence, silt $1.60 LF 100.00 $ 160.00
Mulch, by hand, wood chips, 2" deep $3.25 SY 403.00 $ 1,309.75
Topsoil, delivered and spread $35.73 CY 1654.00 $ 59,097.42
TOTAL $ 67,183.17
$ 75,150.62
ITEMS
Percentage
of
Construction
Cost Unit Cost
Mobilization 10%1 $ 7,515.06
Contingency 30%1 $ 22,545.19
TOTAL $ 30,060.25
MAINTENANCE AND MONITORING
Maintenance, annual (by owner or consultant)
Less than 1,000 sq.ft. and buffer mitigation only $ 1.08 SF $ -
Less than 1,000 sq.ft. with wetland or aquatic area
mitigation $ 1.35 SF $ -
Larger than 1,000 sq. ft. but less than 5,000 sq.ft. of buffer
mitigation $ 180.00 EACH 20.00 $ 3,600.00
Larger than 1,000 sq. ft. but less than 5,000 sq.ft. of
wetland or aquatic area mitigation $ 270.00 EACH $ -
Larger than 5,000 sq.ft. but < 1 acre -buffer mitigation only $ 360.00 EACH $ -
Larger than 5,000 sq.ft. but < 1 acre with wetland or
aquatic area mitigation $ 450.00 EACH $ -
Larger than 1 acre but < 5 acres - buffer and / or wetland or
aquatic area mitigation $ 1,600.00 DAY $ -
Larger than 5 acres - buffer and / or wetland or aquatic
area mitigation $ 2,000.00 DAY $ -
Monitoring, annual (by owner or consultant)
Larger than 1,000 sq.ft. but less than 5,000 wetland or
buffer mitigation $ 720.00 EACH 5.00 $ 3,600.00
Larger than 5,000 sq.ft. but < 1 acre with wetland or
aquatic area impacts $ 900.00 EACH $ -
Larger than 1 acre but < 5 acres - buffer and / or wetland or
aquatic area impacts $ 1,440.00 DAY $ -
Larger than5 acres - buffer and / or wetland or aquatic area
impacts $ 2,160.00 DAY $ -
TOTAL $ 7,200.00
Total $112,410.87
(16 hrs @ $90/hr)
(24 hrs @ $90/hr)
(10 hrs @ $45/hr)
(WEC crew)
(1.25 X WEC crew)
(8 hrs @ $90/hr)
(10 hrs @ $90/hr)
(4hr @$45/hr)
(8 hrs @ 45/hr)
(3 X SF total for 3 annual events;
Includes monitoring)
(3 X SF total for 3 annual events;
Includes monitoring)
(6hr @$45/hr)
Project Name: Wolde Stream Buffer Restoration
Location: 13701 SE May Valley Road, Renton Elias Wolde
OTHER
INSTALLATION COSTS ( LABOR, EQUIPMENT, & OVERHEAD)
Critical Areas Mitigation
Bond Quantity Worksheet
Description
Kerrie McArthur
Project Description: Stream Buffer Mitgation
NOTE: Projects with multiple permit requirements may be required to have
longer monitoring and maintenance terms. This will be evaluated on a case-by-
case basis for development applications. Monitoring and maintance ranges may
be assessed anywhere from 5 to 10 years.
(Construction Cost Subtotal)
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