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3.1 Earth
Construction lmpacts
Subsurface so/s
. Approximately 2.2 million cubic yards of earthwork would occur on the site.
. Approximately 930,000 cubic yards of sand and gravel would be extracted
and available for processing from the east-central portion of the Black Point
Area; this extraction would not alter hydrology.
. Approximately 1 million cubic yards of earthwork would occur on the site.
r Approximately 930,000 cubic yards of sand and gravel would be extracted and
available for processing from the east-central portion of the Black Point Area;
this extraction would not alter hydrology.
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and geotechnical conditions would
generally remain as described under existing conditions as development
occurred within the existing topography.
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and geotechnical conditions would
generally remain as described under existing conditions as development
occurred within the existing topography.
Erosion
. Approximately 167-acres, or 67 percent of the land would be cleared of
vegetation, and significant grading would be required.
. Buffers would be established for protected areas, including slopes; however,
slope instability would be possible if clearing and grading occurred either on
slopes or close to the toe of slopes. Erosion could contribute to sediment in
wetlands and streams.
o Alternative 2 would require approximately 25 percent less surface area
disturbance than Alternative 1.
. Buffers would be established for protected areas, including slopes; however,
slope instability would be possible if clearing and grading occurred either on
slopes or close to the toe of slopes. Erosion could contribute to sediment in
wetlands and streams.
Maritime Village Area
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and geotechnical conditions would
generally remain as described under existing conditions as development
occurred within the existing topography.
o Commercial and residential development would be consolidated into a 3-
story building at the intersection of Black Point Road and U.S. Hwy 101 , and
two 12-unit buildings; reducing impacts on the existing topography in the
Maritime Village Area compared to the 2007 EIS Proposed Action.
. Structures would be built into the existing slope.
. Commercial and residential development would be consolidated into one 3-
story building at the intersection of Black Point Road and U.S. Hwy 101 ,
further reducing impacts on the existing topography in the Maritime Village
Area.
o Structures would be built into the existing slope.
Black Point Area
r The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and geotechnical conditions would
generally remain as described under existing conditions as development
occurred within the existing topography.
. Earth conditions would be similar to those described in the 2007 ElS, and
impacts as a result of site grading would be similar.
. Alternative 2 was modified to improve constructability by refining development
in the existing topographic conditions, resulting in the use of one half less fill
when compared to Alternative 1.
Water Resources
Surface Water
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and potential impacts to water
resources would generally remain as described in the 2007 Final ElS.
. The two small non fish-bearing streams within the Maritime Village Area
would be left in their native condition, buffered, and all stormwater from new
pollution generating surfaces would be captured and treated for both solids
(turbidity) and water quality prior to discharge. As a result, the flows would
be maintained and water quality would be improved. The intermittent non
fish-bearing stream within the WDFW-owned property north of Black Point
Road is located downslope of the new WDFW boat access roadway
alignment, and would not be impacted by construction of the new roadway
alionment.
. Same as Alternative 1
Groundwater and Aquifer Recharge
o This alternative would result in an aquifer recharge of approximately 804 acre-
feet per year. This would be higher than current conditions, but less than
Alternative 1 due to the reduced amount of impervious surfaces and increased
vegetation under Alternative 2.
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and potential impacts to ground
water and aquifer recharge would generally remain as described in the 2007
Final ElS.
. After completion of the resort, aquifer recharge to the sea level aquifer
would be approximately 822 acre-feet per year under Alternative 1,
compared with 760 acre-feet under current conditions. An increase in
recharge is due to a decrease in vegetation due to construction of roads and
buildings. lnfiltration of precipitation would occur more quickly due to
changes in the soil moisture associated with golf course irrigation.
Pleasant Harbor Draft Supplemental EIS
October 2011
Chapter 1
Summary1-4
Alternative 1 Alternative 2 No Action Alternative
TABLE {.{
Stormwater
. Under Alternative 1, 87 percent of the overall site would be retained as open
space, with the golf course, natural areas, and buffers. Stormwater impacts
would occur from an increase in the rate and volume of runoff from
developed areas. Where development allows, frequent and small distributed
bioretention facilities would be provided, and runoff from roof areas would
be infiltrated near the structures producing the runoff. An overflow infiltration
system would be designed around the perimeter of Kettle B, as well as a
direct piped overflow connection to Kettle C for less frequent, larger rainfall
events. The use of reuse water for irrigation would be computer controlled to
prevent runoff.. To prevent runoff entering the Hood Canal in Basins 1,2, and 12,
embankments that change the direction of surface flow would direct runoff
away from Hood Canal into natural and created detention areas This
modification addresses BoCC condition 63 (q). Maritime Village areas would
continue to discharge directly to Pleasant Harbor/Hood Canal, and
prevention of channel erosion due to an increase in runoff would be
required.
. The site would be designed to meet the recommendations of the current
edition of the WDOE's Stormwater Management Manual for Western
Washington together with WDOE's adopted Low lmpact Development
Technical Guidance Manualfor Puget Sound, January 2005.
. lmpacts under Alternative 2 would be similar to those discussed for Alternative
1. Under Alternative 2, 88 percent of the site would be retained as open
space, and stormwater impacts would be similar to Alternative 1, except that
parking areas would be paved with pervious pavements as much as possible
under Alternative 2. Basins 16, 17 , and 18 (including the Maritime Village and
transit stop parking area) would have higher percentages of change under
Alternative 2 because of significantly higher percentages of impervious
surface being constructed in those areas.
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and stormwater impacts would
generally remain as described in the 2007 Final ElS.
Pote nti al Co n str u ctio n I mp a cts
o Stormwater impacts would be largely related to potential water erosion of
disturbed and exposed soils. During construction, stormwater management
measures would be implemented to reduce potential impacts for sediment-
laden water and wind-blown particles to leave the site. Grading activities
could cause sediment-laden waters to cross the property line without proper
mitigation measures. To minimize this potential impact, detailed final
designs would consider redirection of runoff into different basins with better
permeability.
. Similar to Alternative 1
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and potential impacts to water
resources would generally remain as described in the 2007 Final ElS.
Pote ntial Operational lmpacts
o The replacement of existing surfaces and vegetation with less permeable
and impervious surfaces would increase the runoff that enters the
stormwater management facilities. With implementation of the proposed
stormwater control system, significant impacts from surface water runotf
would not be anticipated. The replacement of naturally vegetated areas with
newly landscaped areas would alter surface water runoff and infiltration. The
proposed development would increase stormwater recharge into the
groundwater by approximately 10 percent. New pollutant-generating
impervious surfaces would add additional pollutants to the site from
gasoline, oils, and other mechanicalfluids. These pollutants have the
potential to degrade the quality of water being infiltrated into the ground if
not properly treated.
. Similar to Alternative 1
o The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and potential impacts to water
resources would generally remain as described in the 2007 Final ElS.
Construction
. Proposed development would disturb approximately 73 percent of the site
and existing plant communities. These areas would be cleared of vegetation
and new, maintained landscaping would be provided in pervious areas.
. Proposed development would disturb approximately 55 percent of the site and
existing plant communities. These areas would be cleared of vegetation and
new, maintained landscaping would be provided in pervious areas.
. The site would continue to develop as a single-family residential area based
on the underlying rural residential zoning and plant and vegetation removal
in areas of new development would be limited.
Pleasant Harbor Draft Supplemental EIS
October 2014
Chapter 1
Summary1-5
Alternative 1 Alternative 2 No Action Alternative
Plants