HomeMy WebLinkAboutSEPA Att A2 BE Addendum 2016
To: Pamela Sanguinetti, U.S. Army Corps of Engineers
cc: Robert Smith, Plauché & Carr LLP
Brad Nelson, BDN
From: Grant Novak, Confluence Environmental Company
Date: September 13, 2016
Re: Addendum to Biological Evaluation of BDN LLC Smersh Geoduck Aquaculture Project
(NWS‐2013‐1268)
This document is intended to amend the Biological Evaluation (“BE”) provided by Marine Surveys and
Assessments, Inc., dated October 28, 2013. At the request of the Corps, Confluence has performed
additional eelgrass surveys to confirm the location of native eelgrass (Zostera marina) at the
Smersh/Nelson site. This Addendum updates the BE through updating the location of native eelgrass
on the site, revising the location of proposed geoduck planting consistent with the location of the
eelgrass bed and Corps’ eelgrass buffer requirements, and provides additional analysis regarding the
potential for indirect effects to threatened or endangered species listed under the Endangered Species
Act (ESA) due to potential impacts to eelgrass from geoduck culture and harvest activities. This
Addendum is intended to supplement the original analysis in the BE and any descriptions or analysis
not modified herein should be considered to still be valid and accurate.
A. REVISIONS TO PROJECT DESCRIPTION
Based upon the updated eelgrass survey, BDN has revised its proposed planted area as shown on Figure
1. The revised planted area will consist of approximately 5.15 acres, generally between approximately
+2 ft. MLLW and a 5‐meter (16.4‐ft) buffer of the dense Z. marina bed edge, located between
approximately ‐1 MLLW and ‐2 MLLW.1,2 There are also a couple of minor modifications to BDN’s
proposed operations as compared to what is described in the BE. BDN employees working at the
Smersh parcel will park at public parking areas on Madrona Vista and use property owned by James
1 On a July 21, 2016 site visit, the Corps requested clarification as to whether area netting would be used. As noted
in the original BE, “Area netting over the tubes may be installed to prevent tube dislocation during severe weather”
(BE, pg. 5) and “Once [mesh] caps have been removed, area netting will be put down to contain tubes, as the
growing geoducks will begin to push these out of the sand” (BE, pg. 6). BDN anticipates that area nets may be used
for a maximum of four years to protect geoducks from predators and to provide additional protection against tube
dislodgement.
2 The tidal elevations described herein are approximate. The planted area, location of the eelgrass bed, and extent of
the eelgrass buffer are all described by GPS coordinates that have been provided to the Corps.
Appellant
Exhibit 45 page 1106
May 07 2021
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Smersh located across the street from the project site as a staging area.3 Further, while BDN may use a
skiff in the manner described in Section 4.b.(1) of the BE (pg. 6), most site inspections will be conducted
by walking the beds at low tide.
B. ADDITIONAL EELGRASS SURVEYS
Confluence performed several additional eelgrass surveys on the Smersh parcel. On September 4, 2015,
Confluence used a towed video system with integrated Global Positioning System (GPS) to collect
information about native eelgrass presence/absence. The towed video data were collected in transects
running perpendicular to the beach and spaced about every 45 feet. In addition, a transect that ran
parallel to the shoreline was collected along the anticipated eelgrass bed edge and landward of the
edge. The video system electronically recorded latitude and longitude to aid in the mapping of native
eelgrass locations. A differential GPS (dGPS) with sub‐meter accuracy was used to collect positions at
one second intervals during the towed video surveys. To aid mapping, a proprietary program created by
Confluence was used when reviewing the video to characterize the presence/absence of eelgrass. The
entirety of the field‐collected video data was reviewed in the office on a high definition monitor to
ensure that habitat variables were accurately characterized. Tabular data describing the vegetative
cover, substrate material, relief, and complexity were then joined, using a time stamp, to the dGPS
positions thereby allowing the high quality characterization of video in the office to be linked to the
dGPS positions and video data collected in the field.
During the September 29, 2015 survey, the edge of native eelgrass was confirmed using snorkel‐based
surveys and a dGPS unit at the Smersh site. Two biologists snorkeled the landward native eelgrass
boundary using a floating dGPS unit to precisely collect location data. The biologists divided the area
into two eelgrass zones: patchy vs. continuous. These zones were mapped according to the following
criteria: (1) Patchy = individual shoots or small patches of native eelgrass (typical of shoots migrating
from the main eelgrass bed), (2) Continuous = the main native eelgrass bed with few locations where
eelgrass was absent (typical of a fringe eelgrass bed). The landward edge of the patchy eelgrass zone
was considered to be the upper (or landward) extent of native eelgrass habitat. Underwater video,
using a GoPro HERO4 camera, was collected during the snorkel‐based surveys. The results from the
September 2015 eelgrass surveys are depicted in Figure 2.
Pursuant to the Corps’ request, Confluence conducted another eelgrass survey on the Smersh parcel on
July 20, 2016 to reconfirm the extent of the eelgrass bed surveyed in 2015. A surveyor walked the Z.
marina bed edge, recording the location using a GPS unit with decimeter accuracy. The location of the
marina bed edge was substantially similar to that mapped by Confluence in 2015 and is depicted in
Figure 1.
3 Depending on the source of geoduck seed, the size of planted seed may be 4-5 mm as opposed to the 10-15 mm
seed described in the BE.
Appellant
Exhibit 45 page 1107
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C. ADDITIONAL ANALYSIS REGARDING EFFECTS TO EELGRASS
Effects to eelgrass have the potential to result in changes to ecosystem functions provided by eelgrass
beds at the Smersh/Nelson site and, thereby, to ESA‐listed species that may benefit from those
services.
1. Location of Eelgrass Beds
Both native eelgrass (Z. marina) and non‐native dwarf eelgrass (Zostera japonica) are present at the
proposed Smersh/Nelson geoduck culture site. Z. marina is abundant at subtidal and lower intertidal
elevations, while Z. japonica is very sparsely distributed at higher intertidal elevations. A bed of dense,
robust Z. marina is located seaward of the extreme low tide elevation (approximately ‐2 ft. mean lower
low water [MLLW]) (Figure 1). Landward of this dense bed edge the beach is substantially composed of
bare sand with occasional patches of sparse Z. japonica. No Z. marina is present landward of
approximately ‐2’ MLLW. Planting of geoducks is planned between approximately +2 ft. MLLW and a 5‐
meter (16.4‐ft) buffer of the dense Z. marina bed edge (Figure 1).
2. Effects to Native Eelgrass from Planting and Maintenance Activities
As mentioned above, the project will incorporate a 5‐meter buffer from the identified Z. marina
eelgrass bed, consistent with the Corps’ conservation measure included in the Programmatic Biological
Assessment concerning Shellfish Activities in Washington State Inland Marine Waters (“PBA”). The
Biological Opinions submitted by the National Marine Fisheries Service (“NMFS”) and U.S. Fish &
Wildlife Service both confirm that the buffer will adequately protect eelgrass for new shellfish farms.
For example, NMFS found that new farms “will be required to follow the 16‐foot buffer requirements
from native eelgrass, this is not expected to diminish eelgrass density or function of existing eelgrass.”
NMFS, Endangered Species Act (ESA) Section 7(a)(2) Biological Programmatic Opinion and Magnuson‐
Stevens Fishery Conservation and Management Act Essential Fish Habitat Consultation: Washington
State Commercial Shellfish Aquaculture and Restoration Programmatic (2016), at pg. 72.
3. Impacts to Non‐Native Eelgrass (Z. japonica)
The project may result in the removal of Z. japonica located in the planted area or adverse effects to Z.
japonica from project operations. However, Z. japonica is not a threatened or protected species. To the
contrary, the Washington State Noxious Weed Control Board (NWCB) has classified Z. japonica as a
Class C noxious weed (WAC 16‐750‐015). Aquatic plants on the noxious weed list are considered “to be
highly destructive, competitive, or difficult to control . . .” (WAC 16‐750‐001). In adopting the listing,
the NWCB justified the regulation partially based on concerns that Z. japonica can increase the
deposition of silt and detritus. Protecting Z. japonica would be contrary to the State’s designation of the
Appellant
Exhibit 45 page 1108
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plant as a Class C noxious weed. Therefore, impacts to Z. japonica existing on the site is considered to
be a less than significant impact.4
4 This amends statements made in the original BE that “Z. japonica will not be removed from the site during
planting. Instead, planting will occur through these patches” (BE, pg. 5) and “Still, any activities that reduce harm to
Z. japonica, such as planting around the patches, would maintain additional valuable habitat at this site” (BE, pg.
15). While the initial BE notes that Z. japonica creates three-dimensional habitat and complexity as compared to
mudflats (pg. 15), as noted above, geoduck aquaculture provides similar three-dimensional complexity through the
introduction of tubes and canopy nets. Further, BDN’s operations west of the project site have documented that
BDN’s proposed geoduck aquaculture can coexist with Z. japonica.
Appellant
Exhibit 45 page 1109
www.confenv.com page 5 of 7 Figure 1. Proposed Geoduck Planting Plan and July 2016 Eelgrass Density ZonesAppellant Exhibit 45 page 1110
www.confenv.com page 6 of 7 Figure 2. Proposed Geoduck Planting Plan and September 2015 Eelgrass Density ZonesAppellant Exhibit 45 page 1111