Final
OCEAN DISCHARGE CRITERIA EVALUATION
Ocean Era, Inc. - Velella Epsilon
Net Pen Aquaculture Facility
Outer Continental Shelf
Federal Waters of the Gulf of Mexico
NPDES Permit Number
FL0A00001
September 30, 2020
/*oT\
issj
% pro^N
U.S. Environmental Protection Agency
Region 4
Water Division
61 Forsyth Street SW
Atlanta Georgia 30303
-------
Table of Contents
List of Acronyms 3
1.0 Introduction 4
1.1 Proposed Agency Action 4
1.2 Evaluation Purpose 4
1.3 ODC Evaluation Report Overview 5
2.0 Proposed Project Information 6
2.1 Proposed Project 6
2.2 Proposed Action Area 7
3.0 Physical Environment 8
3.1 Physical Oceanography 8
3.2 Chemical Composition 11
4.0 Discharged Materials 13
4.1 Fish Feed 13
4.2 Fish Wastes 14
5.0 Biological Overview 16
5.1 Primary Productivity 16
5.2 Phytoplankton 17
5.3 Zooplankton 19
5.4 Habitats 19
5.5 Fish and Shellfish Resources 20
5.6 Marine Mammals 21
5.7 Endangered Species 22
6.0 Commercial and Recreational Fisheries 24
6.1 Overview 24
6.2 Commercial Fisheries 24
6.3 Recreational Fisheries 26
7.0 Coastal Zone Management Consistency and Special Aquatic Sites 28
7.1 Coastal Zone Management Consistency 28
7.2 Florida Coastal Management Program 28
7.3 Special Aquatic Sites 29
8.0 Federal Water Quality Criteria and Florida Water Quality Standards 31
8.1 Federal Water Quality Criteria 31
8.2 Florida Water Quality Standards 31
9.0 Potential Impacts 33
9.1 Overview 33
9.2 Water Column Impacts 33
9.3 Organic Enrichment Impacts to Seafloor Sediments 36
9.4 Organic Enrichment Impacts to Benthic Communities 38
9.5 Antibiotics 40
9.6 Waste Deposition Analysis 43
10.0 Evaluation of the Ocean Discharge Criteria 45
10.1 Evaluation of the Ten ODC Factors 45
10.2 Conclusion 48
References 49
Appendix A 59
Appendix B 72
-------
List of Acronyms
BES
Baseline Environmental Survey
BMP
Best Management Practices
BOEM
Bureau of Ocean and Energy Management
CAAP
Concentrated Aquatic Animal Production
CFR
Code of Federal Regulations
CWA
Clean Water Act
CZMA
Coastal Zone Management Act
CZMP
Coastal Zone Management Program
DEP
Department of Economic Opportunity
DWH
Deep Water Horizon
EA
Environmental Assessment
EIS
Environmental Impact Statement
EPA
U.S. Environmental Protection Agency
FAO
Food and Agriculture Organization of the United Nations
FCR
Feed Conversion Ratio
FCMP
Florida Coastal Management Program
FDA
U.S. Food and Drug Administration
FDACS
Florida Department of Agriculture and Consumer Services
FDEP
Florida Department of Environmental Protection
FMP
Fishery Management Plan
FWC
Florida Fish and Wildlife Conservation Commission
GMFMC
Gulf of Mexico Fishery Management Council
HAB
Harmful Algal Blooms
HAPC
Habitat Area of Particular Concern
ITI
Infaunal Tropic Index
MAS
Multi-anchor Swivel
MMS
Minerals Management Service
MM PA
Marine Mammal Protection Act
NCCOS
National Ocean Service National Centers for Coastal Ocean Science
NMFS
National Marine Fisheries Service
NOAA
National Oceanic and Atmospheric Administration
NEPA
National Environmental Policy Act
NPDES
National Pollutant Discharge Elimination System
OCS
Outer Continental Shelf
ODC
Ocean Discharge Criteria
ODMDS
Ocean Dredge Material Disposal Site
OTC
Oxytetracycline
PSMP
Protected Species Monitoring Plan
SAFMC
South Atlantic Fishery Management Council
SOD
Sediment Oxygen Demand
use
United States Code
USFWS
U.S. Fish and Wildlife Service
VE
Velella Epsilon
WQS
Water Quality Standards
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 3 of 85
-------
1.0 Introduction
1.1 Proposed Agency Action
Ocean Era, Inc. (applicant) is proposing to operate a pilot-scale marine aquaculture facility (proposed project)
in federal waters of the Gulf of Mexico (Gulf). Clean Water Act (CWA) Section 402 authorizes the
Environmental Protection Agency (EPA) to issue National Pollutant Discharge Elimination System (NPDES)
permits to regulate the discharge of pollutants into waters of the United States. The EPA action is the
issuance of a NPDES permit that authorizes the discharge of pollutants from an aquatic animal production
facility that is considered a point source into federal waters of the Gulf.
1.2 Evaluation Purpose
The purpose of this Ocean Discharge Criteria (ODC) Evaluation is to identify pertinent information relative to
the ODC and address the EPA's regulations for preventing unreasonable degradation of the receiving waters
for the discharges covered under this NPDES permit. CWA Sections 402 and 403 require that a NPDES permit
for a discharge into the territorial seas (coast to 12 nautical miles, or farther offshore in the contiguous zone
or the ocean), be issued in compliance with EPA's regulations for preventing unreasonable degradation of
the receiving waters. Before issuing a NPDES permit, discharges must be evaluated against EPA's published
criteria for a determination of unreasonable degradation. The NPDES implementing regulations at 40 CFR §
125.121(e) defines unreasonable degradation of the marine environment as the following:
1. Significant adverse changes in ecosystem diversity, productivity, and stability of the biological
community within the area of discharge and surrounding biological communities
2. Threat to human health through direct exposure to pollutants or through consumption of exposed
aquatic organisms, or
3. Loss of aesthetic, recreational, scientific or economic values, which is unreasonable in relation to the
benefit derived from the discharge.
This ODC evaluation addresses the 10 factors for determining unreasonable degradation as required by 40
CFR § 125.122. It also assesses whether the information exists to make a "no unreasonable degradation"
determination, including any recommended permit conditions that may be necessary to reach that
conclusion. The following ten factors are specified at 40 CFR § 125.122 for determining unreasonable
degradation:
1. The quantities, composition, and potential for bioaccumulation or persistence of the pollutants to be
discharged;
2. The potential transport of such pollutants by biological, physical or chemical processes;
3. The composition and vulnerability of the biological communities which may be exposed to such
pollutants, including the presence of unique species or communities of species, the presence of
species identified as endangered or threatened pursuant to the Endangered Species Act (ESA), or the
presence of those species critical to the structure or function of the ecosystem, such as those
important for the food chain;
4. The importance of the receiving water area to the surrounding biological community, including the
presence of spawning sites, nursery/forage areas, migratory pathways, or areas necessary for other
functions or critical stages in the life cycle of an organism;
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 4 of 85
-------
5. The existence of special aquatic sites including, but not limited to, marine sanctuaries and refuges,
parks, national and historic monuments, national seashores, wilderness areas, and coral reefs;
6. The potential impacts on human health through direct and indirect pathways;
7. Existing or potential recreational and commercial fishing, including fin fishing and shell fishing;
8. Any applicable requirements of an approved Coastal Zone Management plan;
9. Such other factors relating to the effects of the discharge as may be appropriate; and
10. Marine water quality criteria developed pursuant to CWA Section 304(a)(1).
If, on the basis of all available information, the EPA determines that the discharge will not cause unreasonable
degradation of the marine environment after application of any necessary conditions, an NPDES permit
containing such conditions can be issued. If it is determined, on the basis of the available information, that
the discharge will cause unreasonable degradation of the marine environment after application of all possible
permit conditions, the EPA may not issue an NPDES permit which authorizes the discharge of pollutants. If
the EPA has insufficient information to determine that there will be no unreasonable degradation of the
marine environment, there shall be no discharge of pollutants into the marine environment unless the
director of the EPA determines that:
1. Such discharge will not cause irreparable harm to the marine environment during the period in which
monitoring is undertaken, and
2. There are no reasonable alternatives to the on-site disposal of these materials, and
3. The discharge will be in compliance with all permit conditions established pursuant to 40 CFR §
125.123(d).
1.3 ODC Evaluation Report Overview
The ODC Evaluation focuses on the sources, fate, and potential effects from discharges at a small-scale
marine aquaculture facility on various groups of marine aquatic life. It also assesses whether the information
exists to make a "no unreasonable degradation" determination, including any recommended permit
conditions that may be necessary to reach that conclusion. Each section of the ODC Evaluation addresses one
of the 10 factors used in making a determination about whether the discharge will cause unreasonable
degradation as shown in Table 1.1.
Table 1.1 - Summary of the ODC Topics
Section
ODC Factor
Description
3
2
Physical and chemical oceanography relevant to the action area
4
land 10
Characteristics, composition, and quantities of materials that potentially will be discharged
from the facility; transport and persistence of pollutants in the marine environment
5
3 and 4
Biological overview of the affected environment
6
7
Information on commercial and recreational fisheries in the receiving water environment
7
5 and 8
Florida Coastal Zone Management Plan (CZMP) and Special Aquatic Sites
8
10
Federal Water Quality Criteria and State Water Quality Standards Analysis
9
1, 2, and 6
Potential impacts on human health, and describes the toxicity and potential for
bioaccumulation of contaminants
10
Summary
Evaluation of the ODC
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 5 of 85
-------
2.0 Proposed Project Information
2.1 Proposed Project
The proposed project would allow the applicant to operate a pilot-scale marine aquaculture facility with up
to 20,000 almaco jack (Seriola rivoliana) being reared in federal waters for a period of approximately 12
months (total deployment of the cage system is 18 months). Based on an estimated 85 percent survival rate,
the operation is expected to yield approximately 17,000 fish. Final fish size is estimated to be approximately
4.4 lbs/fish, resulting in an estimated final maximum harvest weight of 80,000 lbs (or 74,800 lbs considering
the anticipated survival rate). The fingerlings will be sourced from brood stock that are located at Mote
Aquaculture Research Park (Sarasota, FL) and were caught in the Gulf near Madeira Beach, Florida. As such,
only F1 progeny will be stocked into the proposed project.
One support vessel will be used throughout the life of the project. The boat will always be present at the
facility except during certain storm events or times when resupplying is necessary. The support vessel would
not be operated during any time that a small craft advisory is in effect for the proposed action area. The
support vessel is expected to be a 70 foot (ft) long Pilothouse Trawler (20 ft beam and 5 ft draft) with a single
715 HP engine. The vessel will also carry a generator that is expected to operate approximately 12 hours per
day. Following harvest, cultured fish would be landed in Florida and sold to federally-licensed dealers in
accordance with state and federal laws. The exact type of harvest vessel is not known; however, it is expected
to be a vessel already engaged in offshore fishing activities in the Gulf.
A single cage, that is offshore strength fully enclosed submersible fish pen will be deployed on an engineered
multi-anchor swivel (MAS) mooring system. The engineered MAS will have up to three anchors for the
mooring, with a swivel and bridle system. The cage material for the proposed project is constructed with rigid
and durable materials (copper mesh net with a diameter of 4-millimeter (mm) wire and 40 mm x 40 mm
mesh square). The mooring lines for the proposed project will be constructed of steel chain (50 mm thick)
and thick rope (36 mm) that are attached to a floating cage which will rotate in the prevailing current
direction; the floating cage position that is influenced by the ocean currents will maintain the mooring rope
and chain under tension during most times of operation. The bridle line that connects from the swivel to the
cage will be encased in a rigid pipe. Structural information showing the MAS and pen, along with the tethered
supporting vessel, is provided in Appendix A. The anchoring system for the proposed project is being finalized
by the applicant. While the drawings in Appendix A show concrete deadweight anchors, it is likely that the
final design will utilize appropriately sized embedment anchors instead.
The cage design is flexible and self-adjusts to suit the constantly changing wave and current conditions. As a
result, the system can operate floating on the ocean surface or submerged within the water column of the
ocean; however, the normal operating condition of the cage is below the water surface. When a storm
approaches the area, the entire cage can be submerged by using a valve to flood the floatation system with
water. A buoy remains on the surface, marking the net pen's position and supporting the air hose. When the
pen approaches the bottom, the system can be maintained several meters above the sea floor. The cage
system is able to rotate around the MAS and adjust to the currents while it is submerged and protected from
storms near the water surface. After storm events, the cage system is made buoyant, causing the system to
resume normal operational conditions. The proposed project cage will have at least one properly functioning
global positioning system device to assist in locating the system in the event it is damaged or disconnected
from the mooring system.
In cooperation with the National Marine Fishery Service (NMFS), a protected species monitoring plan (PSMP)
has been developed for the proposed action to protect all marine mammal, reptiles, sea birds, and other
protected species. Monitoring will occur throughout the life of the project and is an important minimization
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 6 of 85
-------
measure to reduce the likelihood of any unforeseen potential injury to all protected species including ESA-
listed marine animals. The data collected will provide valuable insight to resource managers about potential
interactions between aquaculture operations and protected species. The PSMP also contains important
mitigative efforts such as suspending vessel transit activities when a protected species comes within 100
meters (m) of the activity until the animal(s) leave the area. The project staff will suspend all surface activities
(including stocking fish, harvesting operations, and routine maintenance operations) in the unlikely event
that any protected species comes within 100 m of the activity until the animal leaves the area. Furthermore,
should there be activity that results in an entanglement or injury to protected species, the on-site staff would
follow the steps outlined in the PSMP and alert the appropriate experts for an active entanglement.1
2.2 Proposed Action Area
The proposed project would be placed in the Gulf at an approximate water depth of 130 ft (40 m),
generally located 45 miles southwest of Sarasota, Florida. The proposed facility will be placed within an area
that contains unconsolidated sediments that are 3 - 10 ft deep (see Table 2.1). The applicant will select the
specific location within that area based on diver-assisted assessments of the sea floor when the cage and MAS
are deployed. More information about the proposed project boundaries are shown in Appendix B. The
proposed action area is a 1,000-meter radius measured from the center of the MAS.
The facility potential locations were selected with assistance from the National Oceanic and Atmospheric
Administration's (NOAA) National Ocean Service National Centers for Coastal Ocean Science (NCCOS). The
applicant and the NCCOS conducted a site screening process over several months to identify an appropriate
project site. Some of the criteria considered during the site screening process included avoidance of corals,
coral reefs, submerged aquatic vegetation, and hard bottom habitats, and avoidance of marine protected
areas, marine reserves, and habitats of particular concern. This siting assessment was conducted using the
Gulf AquaMapper tool developed by NCCOS.2
Upon completion of the site screening process with the NCCOS, the applicant conducted a Baseline
Environmental Survey (BES) in August 2018 based on guidance developed by the NMFS and EPA.3 The BES
included a geophysical investigation to characterize the sub-surface and surface geology of the sites and
identify areas with a sufficient thickness of unconsolidated sediment near the surface while also clearing the
area of any geohazards and structures that would impede the implementation of the aquaculture operation.
The geophysical survey for the proposed project consisted of collecting single beam bathymetry, side scan
sonar, sub-bottom profiler, and magnetometer data within the proposed area. The BES report noted that
there were no physical, biological, or archaeological features that would preclude the siting of the proposed
aquaculture facility at one of the four potential locations shown in Table 2.1.
Table 2.1 - Target Area With 3' to 10' of Unconsolidated Sediments
Location
Latitude
Longitude
Upper Left Corner
27° 7.70607' N
83° 12.27012' W
Upper Right Corner
27° 7.61022' N
83° 11.65678' W
Lower Right Corner
27° 6.77773' N
83° 11.75379' W
Lower Left Corner
27° 6.87631' N
83° 12.42032' W
1 A PSMP has been developed by the applicant with assistance from the NMFS Protected Resources Division. The purpose of the PSMP is
to provide monitoring procedures and data collection efforts for species (marine mammals, sea turtles, seabirds, or other species) protected
under the MMPA or ESA that may be encountered at the proposed project.
2 The Gulf AquaMapper tool is available at: https://coastalscience.noaa.gov/products-explorer/
3 The BES guidance document is available at: http://sero.nmfs.noaa.gov/sustainable_fisheries/Gulf_fisheries/aquaculture/
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 7 of 85
-------
3.0 Physical Environment
3.1 Physical Oceanography
The Gulf is bounded by Cuba on the southeast; Mexico on the south and southwest; and the United States
(U.S.) Gulf Coast on the west, north, and east. The Gulf has a total area of 564,000 square kilometers (km2).
Shallow and intertidal areas (water depths of less than 20 m) compose 38 percent of the total area, with
continental shelf (22 percent), continental slope (20 percent), and abyssal (20 percent) composing the
remainder of the basin.
The Gulf is separated from the Caribbean Sea and Atlantic Ocean by Cuba and other islands and has relatively
narrow connections to the Caribbean and Atlantic through the Florida and Yucatan Straits. The Gulf is
composed of three distinct water masses, including the North and South Atlantic Surface Water (less than
100 m deep), Atlantic and Caribbean Subtropical Water (up to 500 m deep), and Sub Antarctic Intermediate
Water.
3.1.1 Circulation
Circulation patterns in the Gulf are characterized by two interrelated systems, the offshore or open Gulf, and
the shelf or inshore Gulf. Both systems involve the dynamic interaction of a variety of factors. Open Gulf
circulation is influenced by eddies, gyres, winds, waves, freshwater input, density of the water column, and
currents. Offshore water masses in the eastern Gulf may be partitioned into a Loop Current, a Florida
Estuarine Gyre in the northeastern Gulf, and a Florida Bay Gyre in the southeastern Gulf (Austin, 1970).
The strongest influence on circulation in the eastern Gulf is the Loop Current (Figure 3.1). The location of the
Loop Current is variable, with fluctuations that range over the outer shelf, the slopes, and the abyssal areas
off Mississippi, Alabama, and Florida. Within this zone, short-term strong currents exist, but no permanent
currents have been identified (MMS, 1990). The Loop Current forms as the Yucatan Current enters the Gulf
through the Yucatan Straits and travels through the eastern and central Gulf before exiting via the Straits of
Florida and merging with other water masses to become the Gulf Stream (Leipper, 1970; Maul, 1977).
Currents associated with the Loop Current and its eddies extend to at least depths of 700 m with surface
speeds as high as 150-200 centimeters (cm/s), decreasing with depth (BOEM, 2012).
In the shelf or inshore Gulf region, circulation within the Mississippi, Alabama, and west Florida shelf areas is
controlled by the Loop Current, winds, topography, and tides. Freshwater input also acts as a major influence
in the Mississippi/Alabama shelf and eddy-like perturbations play a significant role in the west Florida shelf
circulation. Current velocities along the shelf are variable. Brooks (1991) found that average current velocities
in the Mississippi/Alabama shelf area are about 1.5 cm/s, and east-west and northeast/southwest directions
dominate. MMS (1990) data showed that winter surface circulation is directed along shore and westward
with flow averaging 4 cm/s to 7 cm/s. During the spring and summer, the current shifts to the east with flow
averaging 2 cm/s to 7 cm/s. The mean circulation on the west Florida shelf is directed southward with mean
flow ranging from 0.2 cm/s to 7 cm/s (MMS, 1990).
An EPA study of ocean currents at the Tampa Ocean Dredged Material Disposal Site, which lies 18 miles due
west of Tampa Bay, FL was conducted between 2008-2009 (EPA, 2012). The study showed that current flow
off the west FL coast is predominately in the south-southwest direction (Figure 3.2). Winter months appear
to be dominated by south-southwest currents, whereas north-northeast currents dominated the spring
months. The median surface current was 13 cm/s whereas the median bottom currents were 7 cm/s. The
depth average median current velocity was 9 cm/s.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 8 of 85
-------
Figure 3.1 - Major current regime in the Gulf
100'W 98" 96® 94° 92° 90° 88* 86" 84* 82" 80" 78° W
100° W 98" 96° 94° 92° 90° 88° 86° 84* 82° 80* W
Source: NOAA 2007
Figure 3. 2 - Depth average current rose diagram for the Tampa ODMDS showing current speeds and
direction. (EPA, 2012)
North
0
180
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 9 of 85
-------
Wind patterns in the Gulf are primarily anticyclonic (clockwise around high-pressure areas) and tend to follow
an annual cycle; winterwindsfrom the north and southeastand summerwindsfrom the northeastand south.
During the winter, mean wind speeds range from 8 knots to 18 knots. Several examples of mean annual wind
speeds in the eastern Gulf are 8.0 millibars (mb) in Gulf Port, Mississippi; 8.3 mb in Pensacola, Florida; and
11.2 mb in Key West, Florida (NOAA, 1986).
The tides in the Gulf are less developed and have smaller ranges than those in other coastal areas of the
United States. The range of tides is 0.3 meters to 1.2 meters, depending on the location and time of year.
The Gulf has three types of tides, which vary throughout the area: diurnal, semidiurnal, and mixed (both
diurnal and semidiurnal). Wind and barometric conditions will influence the daily fluctuations in sea level.
Onshore winds and low barometric readings, or offshore winds and high barometric readings, cause the daily
water levels either to be higher or lower than predicted. In shelf areas, meteorological conditions occasionally
mask local tide induced circulation. Tropical storms in summer and early fall may affect the area with high
winds (18+ meters per second), high waves (7+ meters), and storm surge (3 to 7.5 meters). Winter storm
systems also may cause moderately high winds, waves, and storm conditions that mask local tides.
3.1.2 Climate
The Gulf is influenced by a maritime subtropical climate controlled mainly by the clockwise wind circulation
around a semi-permanent, high barometric pressure area alternating between the Azores and Bermuda
Islands. The circulation around the western edge of the high-pressure cell results in the predominance of
moist southeasterly wind flow in the region. However, winter weather is quite variable. During the winter
months, December through March, cold fronts associated with outbreaks of cold, dry continental air masses
influence mainly the northern coastal areas of the Gulf. Tropical cyclones may develop or migrate into the
Gulf during the warmer season, especially in the months of August through October. In coastal areas, the
land-sea breeze is frequently the primary circulation feature in the months of May through October. (BOEM,
2012)
3.1.3 Temperature
In the Gulf, sea surface temperatures range from nearly isothermal (29 - 30°C) in August to a sharp horizontal
gradient in January, ranging from 25°C in the Loop core to values of 14-15°C along the shallow northern
coastal estuaries. A 7°C sea surface temperature gradient occurs in winter from north to south across the
Gulf. During summer, sea surface temperatures span a much narrower range. The range of sea surface
temperatures in the eastern Gulf tends to be greater than the range in the western Gulf, illustrating the
contribution of the Loop Current.
Eastern Gulf surface temperature variation is affected by season, latitude, water depth, and distance
offshore. During the summer, surface temperatures are uniformly 26.6°C or higher. The mean March
isotherm varies from approximately 17.8°C in the northern regions to 22.2°C in the south (Smith, 1976).
Surface temperatures range as low as 10°C in the Louisiana-Mississippi shelf regions during times of
significant snow melt in the upper Mississippi valley (MMS, 1990).
At a depth of 1,000 m, the temperature remains close to 5°C year-round (MMS, 1990). In winter, nearshore
bottom temperatures in the northern Gulf are 10°C cooler than those temperatures offshore. A permanent
seasonal thermocline occurs in deeper off shelf water throughout the Gulf. In summer, warming surface
waters help raise bottom temperatures in all shelf areas, producing a decreasing distribution of bottom
temperatures from about 28°C at the coast to about 18-20°C at the shelf break.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 10 of 85
-------
The depth of the thermocline, defined as the depth at which the temperature gradient is a maximum, is
important because it demarcates the bottom of the mixed layer and acts as a barrier to the vertical transfer
of materials and momentum. The thermocline depth is approximately 30 m in the eastern Gulf during January
(MMS, 1990). In May, the thermocline depth is about 46 m throughout the entire Gulf (MMS, 1990).
3.1.4 Salinity
Characteristic salinity in the open Gulf is generally between 36.4 and 36.5 parts per thousand (ppt). Coastal
salinity ranges are variable due to freshwater input, draught, etc. (MMS, 1990). During months of low
freshwater input, deep Gulf water penetrates the shelf and salinities near the coastline range from 29-32
ppt. High freshwater input conditions (spring-summer months) are characterized by strong horizontal
gradients and inner shelf salinity values of less than 20 ppt (MMS, 1990).
3.2 Chemical Composition
Of the 92 naturally occurring elements, nearly 80 have been detected in seawater (Kenisha, 1989). The
dissolved material in seawater consists mainly of eleven elements. These are, in decreasing order, chlorine,
sodium, magnesium, calcium, potassium, silicon, zinc, copper, iron, manganese, and cobalt (Smith, 1981).
The major dissolved constituents in seawater are shown in Table 3.1. In addition to dissolved materials, trace
metals, nutrient elements, and dissolved atmospheric gases comprise the chemical makeup of seawater.
Table 3.1 - Major dissolved constituents in seawater with a chlorinity of 19%o and a salinity of 34%o
Dissolved substance
(Ion or Compound)
Concentration
(grams per kilogram)
Percent
(by weight)
Chloride (CI )
18.98
55.04
Sodium (Na+)
10.56
30.61
Sulfate (S042")
2.65
7.68
Magnesium (Mg2+)
1.27
3.69
Calcium (Ca2+)
0.40
1.16
Potassium (K+)
0.38
1.1
Bicarbonate (HC03 )
0.14
0.41
Bromide (Br)
0.07
0.19
Boric Acid (H3BO3)
0.03
0.07
Strontium (Sr2+)
0.01
0.04
Fluoride (F )
0.00
0.00
Totals
34.48
99.99
3.2.1 Micronutrients
In Gulf waters, generalizations can be drawn for three principal micronutrients; phosphate, nitrate, and
silicate. Phytoplankton consume phosphorus and nitrogen in an approximate ratio of 1:16 for growth. The
following nutrient levels and distribution values were obtained from MMS (1990): phosphates range from 0
ppm to 0.25 ppm, averaging 0.021 ppm in the mixed layer, and with shelf values similar to open Gulf values;
nitrates range from 0.0031 ppm to 0.14 ppm, averaging 0.014 ppm; silicates range predominantly from 0.048
ppm to 1.9 ppm, with open Gulf values tending to be lower than shelf values.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 11 of 85
-------
In the eastern Gulf, inner shelf waters tend to remain nutrient deficient, except in the immediate vicinity of
estuaries. On occasions when the loop current occurs over the Florida slope, nutrient rich waters are
upwelled from deeper zones (MMS, 1990).
3.2.2 Dissolved Gases
Dissolved gases found in seawater include oxygen, nitrogen, and carbon dioxide. Oxygen is often used as an
indicator of water quality of the marine environment and serves as a tracer of the motion of deep-water
masses of the oceans. Dissolved oxygen values in the mixed layer of the Gulf average 4.6 milligrams per liter
(mg/l), with some seasonal variation, particularly during the summer months when a slight lowering can be
observed. Oxygen values generally decrease with depth to about 3.5 mg/l through the mixed layer (MMS,
1990). In some offshore areas in the northern Gulf, hypoxic (<2.0 mg/l) and occasionally anoxic (<0.1 mg/l)
bottom water conditions are widespread and seasonally regular (Rabalais, 1986). These conditions have been
documented since 1972 and have been observed mostly from June to September on the inner continental
shelf at a depth of 5 to 50 meters (Renauld, 1985; Rabalais et al., 1985).
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 12 of 85
-------
4.0 Discharged Materials
The composition, characteristics, and quantities of materials that will or potentially will be discharged from
the facility under the NPDES permit are considerations under Factor 1 of the 10 factors used to determine
whether unreasonable degradation may occur. The materials to be discharged under NPDES permit to the
Gulf from the proposed project will consist of uneaten fish food pellets and fish wastes.
4.1 Fish Feed
Much of the discussion in this section was developed from information concerning large production scale fish
farms. It is important to note that the proposed project under consideration for this permit will be a small
demonstration project. The proposed project will grow out a maximum of 20,000 fish that would be grown
to 1.8-2.0 kg for one year. The total maximum biomass assuming no mortality is estimated to be
approximately 36,288 kg. Fish will be fed a commercially available grow out diet with 43 percent protein
content. The total maximum daily feed ration at harvest is equivalent to 399 kg at harvest. Maximum daily
excretion of total ammonia nitrogen is estimated at 18-19 kg and maximum total solids production is 161 kg.
A total of 66,449 kg of feed will be used for production of each cohort of fish to achieve a feed conversion
ratio (FCR) of 1.8.
The quantities of food supplied per unit of fish depend on the type of food used, size of the fish, and the
water temperature. A typical salmon farm producing 340 metric tons (748,000 lbs) of fish annually will feed
340 to 680 metric tons (748,000-1,496,000 lbs) of food (Wash Dept. Fisheries, 1989). Fish cultured around
the world are fed a variety of foods, ranging from minced trash fish, to semi-moist pellets of minced fish and
various binders, to dry pellets. Semi-moist or dry pellets are used extensively in U.S. fish farms and consist of
a combination of fish meal and vegetable matter, mixed with vitamins, essential oils and other organic
material. Some studies have shown that when feeding methods are optimized, there is generally no
significant difference between pelletized artificial feeds and the use of trash fish regarding the discharge of
nutrients and solid materials from cages (Hasan, 2012). Table 4.1 shows the composition of several commonly
used prepared fish diets. Typical average levels of protein, fats and carbohydrates in fish feeds ranges from
18-50 percent, 10-25 percent and 15-20 percent respectively, depending on targeted species (Waldemar
Nelson International, 1997; Craig, 2009). The proposed permit prohibits the discharge of un-pelletized wet
feeds.
The effectiveness of cultured fish feeding methods and diets are measured by calculating a FCR - the ratio of
food fed (dry weight) to fish produced (wet weight). Typically, average FCR's range from 1:1 for salmonid
fishes to 2:1 for some freshwater species (Hasan and Soto, 2017). That is, for every pound offish produced,
1 to 2 lbs of feed were introduced into the water. In some laboratory experiments, FCR's of less than 1:1 have
been achieved, and most fish farmers now claim values between 1 and 1.5. The amount fed during any period
depends primarily upon the type of food used, the size of the fish, and the water temperature. Farmed fish
are typically fed 1-4 percent of their body weight per day. Though protein content may vary, generally, fish
feed includes about 7.7 percent nitrogen (Edwards, 1978) and 37.7 percent organic carbon (Waldemar
Nelson International, 1997).
Modern feeds are designed to reduce solid wastes by improving digestibility, ingredient selection and
nutrient balance (Cho and Bureau, 2001). Even with the highest FCRs, a portion offish feed is not eaten and
settles to the bottom. Feed wastage has proven difficult to ascertain in field conditions. However, several
studies in Europe have suggested that a range of 1 to 30 percent of the feed may be lost (Gowen et al 1988;
Pencsak et al., 1982). Dry feed consistently showed the least amount of wastage (1 to 5 percent) while 5 to
10 percent of moist fish foods were lost (Gowen and Bradbury, 1987). In Puget Sound farms, fish growers
report that food wastage is typically less than 5 percent (Weston, 1986). Specific studies of food wastage at
a commercial salmon farm in Sooke Inlet, B.C., showed that hand feeding, the most common practice in Puget
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 13 of 85
-------
Sound, resulted in wastage of 3.6 percent. The use of automatic feeders increased wastage to 8.8 percent
(Cross, 1988).
Since food pellets do not decompose appreciably as they settle to the bottom, they are unlikely to experience
substantial reduction in nitrogen or carbon, either through solution or microbial activity, before depositing
on the bottom (Collins, 1983; Gowen and Bradbury, 1987). Thus, any food particles or pellets lost during
feeding will retain their nutrients essentially unaltered. Development of slower settling feeds, which are
available to the fish in the pens for longer periods, and feeds with more uniform size have reduced wastage.
However, the amount of wastage is still highly dependent upon the care used by the fish farmer during
feeding.
Table 4.1 - Nutritional composition of commonly used prepared fish diets 4
Source
Fish Species
Feed Brand
Feed
Type
%
Protein
%
Fats
%
Carbohydrates
BioProducts, Inc (EPA, 1991)
Salmon
Biodry 3000
Dry
44.5
15.0
14.7
Moore-Clark Co. (EPA, 1991)
Salmon
Select Ext.
Dry
45.0
22.0
14.0
BioProducts, Inc (EPA, 1991)
Salmon
Biomoist F.3
Moist
39.0
13.5
11.8
Moore-Clark Co. (EPA, 1991)
Salmon
Oregon Moist
Dry
35.0
11.0
13.0
Ziegler Bros. (Ellis, 1996)
Grouper
Trout Grower
Dry
43.5
5.9
34.8
Rangen, Inc. (Ellis, 1996)
Grouper
Salmon Grower
Dry
52.7
15.2
13.8
Dainichi Corp. (Ellis, 1996)
Grouper
Cam. Fish Diet
Dry
55.6
7.8
20.7
Oceanic Institute (Ellis, 1996)
Grouper
Mahi ex.diet
Dry
61.8
14.2
12.9
Corey Feed Mills
Salmon
Fundy Choice
Dry
43.0
30.0
11.0
Aquaculture 1997 v. 151
Grouper
-
Dry
43.0
14.0
8.0
Oceanic Institute, 1993
Mahi-Mahi
01 prepared diet
Dry
60.0
12.0
10.0
Williams, 1985
Pompano
Menhaden oil diet
Dry
42.0
12.0
7.0
Burris Mill & Feed
Hybrid Bass
Grower
Dry
42.0
7.0
19.0
Burris Mill & Feed
Red Drum
Grower
Dry
42.0
7.0
19.0
Burris Mill & Feed
Red Drum
Grower
Dry
40.0
10.0
30.0
Mean
45.9
13.1
16.0
4.2 Fish Wastes
Of the feed consumed, about 10 percent is lost as solid wastes and 30 percent lost as liquid wastes (Butz and
Vens-Capell, 1982; Craig, 2009). Unlike feed pellets, fish feces are more variable in size and density.
Consequently, the settling rate of these particles will vary greatly, but will be less than that of feed pellets.
The composition of the feces is dependent upon the chemical composition of the feed and its digestibility.
Gowen and Bradbury (1987) estimated from the literature that about 30 percent of the consumed carbon
would be excreted in the feces, along with about 10 percent of the consumed nitrogen.
4 Source: Modified from Waldemar Nelson International, 1997.
ODC Evaluation Page 14 of 85
Ocean Era, Inc. - Velella Epsilon
-------
Estimates of the total particulate matter emanating from net pens, for eventual deposit on the sea floor,
have been calculated. Weston (1986), assuming an FCR of 2:1 with 5 percent wastage and a third of the
consumed food being lost as feces, estimated that 733 kg (1,600 lbs) of sediment would be produced for
every metric ton (2200 lbs) offish grown. The Institute of Aquaculture (1988) estimated sediment production
of 820 kg (1800 lbs), assuming 20 percent wastage and a 30 percent loss as feces.
A discharge limitation will be placed in the NPDES permit to state that fish food and metabolic wastes
discharged from the facility shall not cause unreasonable degradation of the environment beneath the facility
and/or the surrounding area as defined in 40 CFR § 125.122(a).
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 15 of 85
-------
5.0 Biological Overview
This chapter describes the biological communities and processes in the eastern Gulf in general and in the
specific area of the proposed facility which may be exposed to pollutants, the potential presence of
endangered species, any unique species or communities of species, and the importance of the receiving
water to the surrounding biological communities.
5.1 Primary Productivity
Primary productivity is "the rate at which radiant energy is stored by photosynthetic and chemosynthetic
activity of producer organisms in the form of organic substances which can be used as food materials" (Odum,
1971). Primary productivity is affected by light, nutrients, and zooplankton grazing, as well as other
interacting forces such as currents, diffusion, and upwelling. The producer organisms in the marine
environment consist primarily of phytoplankton and benthic macrophytes. Since benthic macrophytes are
depth/light limited, primary productivity in the open ocean is attributable primarily to phytoplankton. The
productivity of nearshore waters can be attributed to benthic macrophytes-including seagrasses,
mangroves, salt marsh grasses, and seaweeds-and phytoplankton.
There are numerous methods for estimating primary productivity in marine waters. One method is to
measure chlorophyll content per volume of seawater and compare results over time to establish a
productivity rate. The chlorophyll measurement, typically of chlorophyll a, gives a direct reading of total plant
biomass. Chlorophyll a is generally used because it is considered the "active" pigment in carbon fixation
(Steidinger and Williams, 1970). Another method, the C14 (radiocarbon) method, measures photosynthesis
(a controversy exists as to whether "net", "gross", or "intermediate" photosynthesis is measured by this
method; Kennish, 1989). The C14 method introduces radiolabeled carbon into a sample and estimates the
rate of carbon fixation by measuring the sample's radioactivity. The units used to express primary
productivity are grams of carbon produced in a column of water intersecting one square meter of sea surface
per day (g C/m2/d), or grams of carbon produced in a given cubic meter per day (g C/m3/d).
C14 uptake throughout the Gulf is 0.25 g C/m3/hr or less, and chlorophyll measurements range from 0.05 to
0.30 mg/m3 (ppb). Eastern regions of the Gulf are generally less productive than western regions, and
throughout the eastern Gulf, primary productivity is generally low. However, outbreaks of "red-tide" caused
by pathogenic phytoplankton may occur in the mid- to inner-shelf. Also, depth-integrated productivity values
in the area of the Loop Current (primarily the outer shelf and slope) are actually higher than western and
central Gulf values. Enhanced productivity occurs in areas affected by upwelling. Near the bottom of the
euphotic zone, chlorophyll and productivity values are about an order of magnitude greater, probably due to
the often intruded, nutrient-rich Loop undercurrent waters (MMS, 1990).
Productivity measurements in the oceanic waters of the Gulf include: 0.1 g C/m2/d yielding 17 g C/m2/yr or
86 million tons of phytoplankton biomass (MMS, 1983); 103-250 g C/m2/yr (Flint and Kamykowski, 1984);
103 g C/m2/yr (Flint and Rabalais, 1981). For comparisons, the following data on primary productivity are
presented for coastal wetland systems as compiled by Thayer and Ustach (1981):
• Salt Marshes, 200-2000 g C/m2/yr
• Mangroves, 400 g C/m2/yr
• Seagrasses, 100-900 g C/m2/yr
• Spartina alterniflora, 1300 g C/m2/yr
• Thalassia, 580-900 g C/m2/yr
• Phytoplankton, 350 g C/m2/yr
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 16 of 85
-------
Biomass (chlorophyll a) measurements in the predominantly oceanic waters of the Gulf include: 0.05-0.30
mg Chi a/m3 (MMS, 1983a); 0.05-0.1 mg Chi a/m3 (Yentsch, 1982); 0.22 mg Chi a/m3 (El-Sayed, 1972); and
0.17 mg Chi a/m3 (Trees and El-Sayed, 1986). For the eastern Gulf, biomass (chlorophyll a) measurements
include the following (Yoder and Mahood, 1983):
• Surface mixed layer values of 0.1 mg/m3;
• Subsurface measurements at 40-60 m ranged from 0.2 to 1.2 mg/m3;
• Average integrated values for the water column over the 100-200 m isobath was 10 mg/m2; and
• Average integrated values for the water column greater than 200 m isobath was 9 mg/m2.
5.2 Phytoplankton
5.2.1 Distribution
Phytoplankton distribution and abundance in the Gulf is difficult to measure. Shipboard or station
measurements cannot provide information about large areas at one moment in time, and satellite imagery
cannot provide definitive information about local conditions that may be important. Due to fluctuations in
light and nutrient availability and the immobility of phytoplankton, distribution is temporally and spatially
variable. Seasonal fluctuations in location and abundance are often masked by patchy distributions which
human sampling designs must attempt to interpret. In addition, methods for measurement of chlorophyll or
uptake of carbon cannot always resolve all questions concerning variability among or within species under
different conditions, or those concerning the effects of grazing on abundance.
As mentioned in the previous section, phytoplankton occupy a niche at the base of food chain as primary
producers of our oceans. Herbivorous zooplankton populations require phytoplankton for maintenance and
growth - generally 30-50 percent of their weight each day and surpassing 300 percent of their weight in
exceptional cases (Kennish, 1989). In the Gulf, phytoplankton are also often closely associated with bottom
organisms, and may also contribute to benthic food sources for demersal feeding fish.
Phytoplankton seasonality has been explained in terms of salinity, depth of light penetration, and nutrient
availability. Generally, diversity decreases with decreased salinity and biomass decreases with distance from
shore (MMS, 1990).
5.2.2 Principal Taxa
The principal taxa of planktonic producers in the ocean are diatoms, dinoflagellates, coccolithophores,
silicoflagellates and blue-green algae (Kennish, 1989).
Diatoms
Many specialists regard diatoms as the most important phytoplankton group, contributing substantially to
oceanic productivity. Diatoms consist of single cells or cell chains, and secrete an external rigid silicate
skeleton called a frustule. In 1969, Saunders and Glenn reported the following for diatom samples collected
5.6 to 77.8 kilometers (km) from shore in the Gulf between St. Petersburg and Ft. Myers, Florida. Diatoms
averaged 1.4 x 107|i2/l surface area offshore, 13.6 x 107|i2/l at intermediate locations and 13.0 x 108|i2/l
inshore. The ten most important species in terms of their cellular surface area were: Rhizosolenia alata, R.
setigera, R. stolterfothii, Skeletonema costatum, Leptocylindrus danicus, Rhizosolenia fragilissima,
Hemidiscus hardmanianus, Guinardia flaccida, Bellerochea malleus, and Cerataulina pelagica.
Dinoflagellates
Dinoflagellates are typically unicellular, biflagellated autotrophic forms that also supply a major portion of
the primary production in many regions. Some species generate toxins and when blooms reach high
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 17 of 85
-------
densities, mass mortality of fish, shellfish, and other organisms can occur (Kennish, 1989). Notably,
Gymnodinium breve is responsible for most of Florida's red tides and several of the Gonyaulax species are
known to cause massive blooms (Steidinger and Williams, 1970). Table 5.1 lists species and varieties of
dinoflagellates found to be abundant during the Hourglass Cruises (a systematic sampling program in the
eastern Gulf.)
Table 5.1 - Significant Dinoflagellate Species of the Eastern Gulf5
Species
Biomass Value (ji3)
Amphibologia bidentata
67,039 - 95,406
Ceratium carriense
637,219- 1,115,367
C. carriense var. volans
622,206-1,196,643
C. contortum var. karstenii
943,121 - 1,655,573
C. extensum
189,709 - 323,546
C. furca
23,157-43,369
C. fusus
34,463 -154,722
C. hexacanthum
687,593 - 1,384,016
Ceratium hircus
211,709
C. inflatum
145,897-221,276
C. massiliense
543,762 - 1,002,222
C. trichoceros
104,110-357,437
C. tripos var. atlanticum
518,659 - 964,436
Dinophysis caudata var. pedunculata
92,153-231,405
Gonyaulax splendens
51,651
Prorocentrum crassipes
329,540
P. gracile
25,773
P. micans
65,412
Coccolithophores
Coccolithophores are unicellular, biflagellated algae named for their characteristic calcareous plate, the
coccolith, which is embedded in a gelatinous sheath that surrounds the cell. Phytoplankton of offshore Gulf
are reported to be dominated by coccolithophores (Iverson and Hopkins, 1981).
Silicoflagellates
Silicoflagellates are unicellular flagellated (single or biflagellated) organisms that secrete an internal skeleton
composed of siliceous spicules (Kennish, 1989). Perhaps because of their small size (usually less than 30 |im
in diameter) little specific information relative to Gulf distribution and abundance, is available for this group.
Blue Green Algae
Blue green algae are prokaryotic organisms that have chitinous walls and often contain a pigment called
phycocyanin that gives the algae their blue green appearance (Kennish, 1989). On the west Florida shelf,
inshore blooms of the blue green algae Oscillatoria erethraea sometimes occur in spring or fall.
5 Source: Steidinger and Williams, 1970.
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 18 of 85
-------
5.3 Zooplankton
Like phytoplankton, zooplankton are seasonal and patchy in their distribution and abundance. Zooplankton
standing stocks have been associated with the depth of maximum primary productivity and the thermocline
(Ortner et al., 1984). Zooplankton feed on phytoplankton and other zooplankton, and are important
intermediaries in the food chain as prey for each other and larger fish.
As in many marine ecosystems, zooplankton fecal pellets contribute significantly to the detrital pool. The
ease of mixing in Gulf coastal waters may make them extremely important to nutrient circulation and primary
productivity, as well as benthic food stocks. Also contributing to the detrital pool is the concentration of
zooplankton in bottom waters, coupled with phytoplankton in the nepheloid layer during times of greater
water stratification.
Copepods are the dominant zooplankton group found in all Gulf waters. They can account for as much as 70
percent by number of all forms of zooplankton found (NOAA, 1975). In shallow waters, peaks occur in the
summer and fall (NOAA, 1975), or in spring and summer, (MMS, 1983a). When salinities are low, estuarine
species such as Acartia tonsa become abundant.
The following information on zooplankton distribution and abundance in the eastern Gulf is summarized
from Iverson and Hopkins (1981):
• During Bureau of Land Management-sponsored studies, small copepods predominated in net catches
over the shelf regions of the eastern and western Gulf.
• During Department of Energy-sponsored studies at sights located over the continental slope of Mobile
and Tampa Bays, small calanoids such as Parcalanus, and Clausocalanus and cyclopoids such as
Farralanula, Oncaea, and Oithona predominated at the 0-200 m depths; and larger copepods such as
Eucalanus, Rhincalnus, and Pleuromamma dominated at 1,000 m depths. Euphausiids were also more
conspicuous. Night-time samples taken near Tampa showed larger crustaceans such as Lucifer and
Euphasia. Biomass data for the same site revealed a decrease in zooplankton with increasing depth. The
mean cumulated biomass value for the upper 1,000 m was 21.9 ml/m2.
• Studies funded by the National Science Foundation in the east-central Gulf found diurnal patterns of
distribution in the upper 1,000 m, with increases in the 50 m range at night and in the 300-600 m zone
during the day, most likely attributable to vertical migration. In the upper 200 m, in addition to copepods,
group such as chaetognaths, tunicates, hydromedusae, and euphausiids were significant contributors to
the biomass.
Icthyoplankton studies forthe eastern Gulf conducted during 1971-1974 found fish eggs to be more abundant
in the northern half and fish larvae to be more abundant in the southern half of the eastern Gulf. Mean
abundances were 5,454 eggs/m2 and 3,805 larvae/m2 in the northern Gulf and 4,634 eggs/m2 and 4,869
larvae/m2 in the southern Gulf. Eggs were more abundant in waters less than 450 meters deep, whereas
larvae were more abundant in-depth zones greater than 50 meters (Houde and Chitty, 1976).
5.4 Habitats
5.4.1 Seagrasses
Seagrasses are vascular plants that serve a variety of ecologically important functions. As primary producers,
seagrasses are a direct food source and also contribute nutrients to the water column. Seagrass communities
serve as a nursery habitat for juvenile fish and invertebrates and seagrass blades provide substrate for
epiphytes. Species such as Thalassia testudinum have an extensive root system that stabilize substrate, and
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 19 of 85
-------
broad ribbon-like blades that increase sedimentation. Seagrasses mainly occur in shallow, clear, highly saline
waters. Seagrass beds do not occur in the proposed activity area.
Approximately 1.25 million acres of seagrass beds are estimated to exist in exposed, shallow,
coastal/nearshore waters and embayments of the Gulf. About 3 percent of these beds are in Mississippi.
Florida with Florida Bay and coastal Florida accounting for more than 80 percent. True seagrasses that occur
in the Gulf are shoal grass, paddle grass, star grass, manatee grass, and turtle grass. Although not considered
a true seagrass because it has hydroanemophilous pollination (floating pollen grains) and can tolerate
freshwater, widgeon grass is common in the brackish waters of the Gulf. (BOEM, 2012).
5.4.2 Offshore Habitats
Offshore habitats include the water column and the sea floor. The west Florida Shelf extends seaward of
Tampa Bay approximately 200 km to a depth of 200 m and consists mainly of unconsolidated sediments
punctuated by low-relief rock outcroppings and several series of high relief ridges. The seafloor on the west
Florida shelf in the proposed project area consists mainly of course to fine grain sands with scattered
limestone outcroppings making up about 18 percent of the seafloor habitat. These limestone outcroppings
provide substrata for the attachment of macroalgae, stony corals, octocorals, sponges and associated hard-
bottom invertebrate and fish communities (EPA, 1994).
5.5 Fish and Shellfish Resources
The distribution of fish resources in the eastern Gulf are highly dependent on a variety of factors including
habitat type, chemical and physical water quality variables, biological, and climatic factors. The Gulf contains
both a temperate fish fauna and a tropical fauna arrayed into inshore and offshore habitats depending on
latitude. To the south of the 20°C winter isotherm, approximately middle Florida, the more tropical fish fauna
occupies inshore habitats replacing the temperate fauna. To the north the tropical fauna is pushed further
offshore to avoid cold winter temperature and by increased competition by temperate species able to
tolerate cooler waters. In the northern Gulf where temperate species dominate inshore, a well-developed
tropical fauna occurs on offshore structures, particularly reefs (Hoese and Moore, 1977). During warm
weather the early life stages of the tropical fauna move further inshore around piers and jetties.
The temperate fish and invertebrate fauna of the north-central Gulf tend to be dominated by estuary
dependent species such as sciaenids (i.e., croaker, red and black drum, spotted seatrout), menhaden, shrimp,
oysters and crabs. These species require the transportation of early life stages into estuaries for grow out
into mature adults or juveniles and migration out to shelf environments. Shellfish resources in the Gulf tend
to be more estuarine dependent than finfishes. Gulf shellfish habitats range from brackish wetlands to
nearshore shelf environments. Of the 15 penaeid shrimp species found in the Gulf the brown, white and pink
shrimp are the most important. Adults of these species spawn in offshore marine waters and the free-
swimming post larvae move into estuaries to remain through their juvenile stages. Juvenile shrimp move
back offshore to molt into adults.
Reef fish assemblages may consist of mainly temperate species in the more northern Gulf with increasing
dominance of more tropical fish species, typically associated with coral reefs, further offshore and in the
more southern portions of the Gulf. Natural reef habitat in the eastern Gulf ranges from low relief (>1 m) live
bottom, high relief ridge habitats along the Florida shelf break and pinnacle formations of the Florida Middle
Grounds on the west Florida shelf. Man-made or artificial reef habitats also exist from oil and gas platforms,
sunken vessels and a variety of other structures placed intentionally for fisheries enhancement. These
structures comprise critical habitats for many important commercial and recreational fishes such as groupers
and snappers.
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 20 of 85
-------
Pelagic fish species are distributed by water column depth and relationship to the shore. Coastal pelagic fish
are those that move mainly around the continental shelf year-round, singly or in schools of various size. These
include some commercially important groups of fishes including sharks, anchovies, herring, mackerel, tuna,
mullet, bluefish and cobia. Oceanic pelagic fish occur at or seaward of the shelf edge throughout the Gulf.
Oceanic pelagic fish include many larger species such as sharks, tuna, bill fishes, dolphin and wahoo.
Extensive discussions of reef and migratory fish species in the Gulf can be found in the Final Programmatic
Environmental Impact Statement. Fishery Management Plan for Regulating Offshore Marine Aquaculture in
the Gulf (NOAA 2009).
A 2010 survey of the Tampa Ocean Dredge Material Disposal Site (ODMDS) that is approximately 18 miles
west of Tampa Bay, identified 29 species of demersal fishes associated with the high relief habitat created by
the dredged material spoil mound, with only 9 species on nearby natural low-relief hard bottom habitat.
Abundances of fishes on natural low-relief hard bottom in the area were also significantly smaller than on
the spoil mound (EPA, 2011).
5.6 Marine Mammals
All marine mammals are protected under the Marine Mammal Protection Act of 1972 (MMPA). There are 22
marine mammal species that may occur in the Gulf (i.e., one sirenian species (a manatee), and 21
cetacean species (dolphins and whales)) based on sightings and/or strandings (Schmidly, 1981; NOAA,
2009). Three of the marine mammals (sperm whales, Gulf Bryde's whale, and manatees) are also
currently protected under the ESA.
Cetaceans (whales, dolphins, and porpoises) are the most common. Six of the seven baleen whales in the
Gulf are currently listed as threatened or endangered and of the 20 toothed whales present only the sperm
whale is endangered. During 1978 to 1987, a total of 1,200 cetacean strandings/sightings was reported for
Alabama, Florida and Mississippi to the Southeastern U.S. Marine Strandings Network. Ninety percent of
these stranding/sighting occurred off Florida coasts (the Florida figure reflects strandings from both the Gulf
and the Atlantic waters (NOAA, 1991). The cetaceans found in the Gulf include species that occur in most
major oceans, and for the most part are eurythermic with a broad range of temperature tolerances (Schmidly,
1981). An introduced species of pinniped, the California sea lion, occurred in small numbers only in the feral
condition, however no sightings of this species has been reported in the Gulf since 1990.
Most of the Gulf cetacean species reside in the oceanic habitat (greater than or equal to 200 m). However,
the Atlantic spotted dolphin (Stenella frontalis) is found in waters over the continental shelf (10-200 m), and
the common bottlenose dolphin (Tursiops truncatus truncatus) (hereafter referred to as bottlenose dolphins)
is found throughout the Gulf, including within bays, sounds, and estuaries; coastal waters over the
continental shelf; and in deeper oceanic waters. Bottlenose dolphins in the Gulf can be separated into
demographically independent populations called stocks. Bottlenose dolphins are currently managed by
NOAA Fisheries as 36 distinct stocks within the Gulf. These include 31 bay, sound, and estuary stocks, three
coastal stocks, one continental shelf stock, and one oceanic stock (Hayes et a I., 2017).6
More extensive discussions about marine mammals for the proposed project are within the Environmental
Assessment (EA) for the proposed project. Additionally, more information about marine mammals in the Gulf
can be found in the Final Programmatic Environmental Impact Statement (EIS) Fishery Management Plan for
Regulating Offshore Marine Aquaculture in the Gulf (NOAA, 2009), the EA for the EPA Oil and Gas general
6 Marine Mammal Stock Assessment Reports and additional information on these species in the Gulf are available on the NOAA Fisheries
Office of Protected Species website: www.nmfs.noaa.gov/pr/sspecies/.
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 21 of 85
-------
NPDES permit (EPA, 2016), and in recent Bureau of Ocean and Energy Management (BOEM) EIS documents
(BOEM, 2012).
5.7 Endangered Species
The USFWS and NMFS evaluate the conditions of species and their populations within the United States.
Those species populations considered in danger of extinction are listed as endangered species pursuant to
the Endangered Species Act of 1973. In addition, Section 7(a)(2) of the ESA requires federal agencies to
ensure that their action do not jeopardize the continued existence of listed species or destroy or adversely
modify critical habitat. Table 5.2 provides the list of ESA-listed species that were considered by the EPA and
could potentially occur in or near the proposed action area.
More information about endangered species can be found in the Biological Evaluation for the proposed
project. Overall, potential impacts to the ESA-listed species considered by the EPA are expected to be
extremely unlikely and insignificant due to the small size of the facility, the short deployment period, unique
operational characteristics, lack of geographic overlap with habitat or known migratory routes, or other
factors that are described in the below sections for each species.
Threatened and endangered species that occur in the Gulf are discussed extensively in the 2016 EPA
Environmental Assessment for the EPA Oil and Gas general NPDES permit (EPA, 2016), BOEM EIS documents
(BOEM, 2013), and the Final PEIS for Offshore Marine Aquaculture in the Gulf (NOAA, 2009).
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 22 of 85
-------
Table 5.2 - Federally Listed Species, Listed Critical Habitat, Proposed Species, and Proposed Critical
Habitat Considered for the Proposed Action
Species Considered
ESA Status
Critical Habitat
Status
Potential Exposure to
Proposed Action Area
Birds
1 Piping Plover
Threatened
Yes
No
2 Red Knot
Threatened
No
No
Fish
1 Giant Manta Ray
Threatened
No
Yes
2 Nassau Grouper
Threatened
No
Yes
3 Oceanic Whitetip Shark
Threatened
No
Yes
4 Smalltooth Sawfish
Endangered
No
Yes
Invertebrates
1 Boulder Star Coral
Threatened
No
No
2 Elkhorn Coral
Threatened
No
No
4 Mountainous Star Coral
Threatened
No
No
5 Pillar Coral
Threatened
No
No
7 Staghorn Coral
Threatened
No
No
6 Rough Cactus Coral
Threatened
No
Yes
3 Lobed Star Coral
Threatened
No
Yes
Marine Mammals
1 Blue Whale
Endangered
No
Yes
2 Bryde's Whale
Endangered
No
Yes
3 Fin Whale
Endangered
No
Yes
4 Humpback Whale
Endangered
No
Yes
5 Sei Whale
Endangered
No
Yes
6 Sperm Whale
Endangered
No
Yes
Reptiles
1 Green Sea Turtle
Threatened
No
Yes
2 Hawksbill Sea Turtle
Endangered
Yes
Yes
3 Kemp's Ridley Sea Turtle
Endangered
No
Yes
4 Leatherback Sea Turtle
Endangered
Yes
Yes
5 Loggerhead Sea Turtle
Threatened
Yes
Yes
ODC Evaluation
Ocean Era, Inc.- Velella Epsilon
Page 23 of 85
-------
6.0 Commercial and Recreational Fisheries
6.1 Overview
Though the Gulf Region includes Alabama, Louisiana, Mississippi, Texas, and West Florida, much of the
following discussion will focus on Gulf states in the eastern portion of the Gulf. Federal fisheries in this region
are managed by the Gulf Fishery Management Council (GMFMC) and the NMFS under seven fishery
management plans (FMPs): Red Drum, Shrimp, Reef Fish, Coastal Migratory Pelagic Resources (with SAFMC),
Spiny Lobster (with SAFMC), Corals, and Aquaculture. The coastal migratory pelagic resources and spiny
lobster fisheries are managed in conjunction with the South Atlantic Fishery Management Council (SAFMC).
Several of the stocks or stock complexes covered in these fishery management plans, are currently listed as
overfished: gray snapper, greater amberjack, and lane snapper.7 Other impacts to commercial fisheries in the
Gulf in recent years include a number of hurricanes, especially with major storms making landfall in Louisiana
and Texas in 2005 (Hurricanes Katrina and Rita) and 2008 (Hurricanes Gustav and Ike). Locally, these storms
severely disrupted or destroyed the infrastructure necessary to support fishing, such as vessels, fuel and ice
suppliers, and fish houses.8
The Deepwater Horizon oil spill in 2010 severely affected fisheries in the Gulf. Large parts of the Gulf,
including state and federal waters, were closed to fishing during May through October, 2010. Both Alabama
and Mississippi reported less than half and Louisiana about three quarters of their annual shrimp landings
compared to the average of the previous three years. The impacts of the spill remain under study and the
long-term consequences of the oil spill on fish stocks and the fishing industry have yet to be fully assessed.
6.2 Commercial Fisheries
Information from the NMFS in 2013 shows that commercial fishermen in the Gulf Region landed 1.4 billion
pounds of finfish and shellfish, earning $937 million in landings revenue (NMFS, 2014; NMFS, 2015). In 2014
1.1 billion pounds were landed at a value of over $1.0 billion. From 2003 to 2013, most of the commercial
fisheries revenue and catch (91 percent and 96 percent respectively) was dominated by ten key species or
species groups (Table 6.1).
Commercially important species groups in the Gulf include oceanic pelagic (epipelagic) fishes, reef (hard
bottom) fishes, coastal pelagic species, and estuarine-dependent species. Landings revenue in 2012 was
dominated by shrimp ($392 million) and menhaden ($87 million). These species comprised 63 percent of
total landings revenue, and 90 percent of total landings in the Gulf Region. Other invertebrates such as blue
crab, spiny lobster, and stone crab also contributed significantly to the value of commercial landings. Other
finfish species that contributed substantially to the overall commercial value of the Gulf fisheries included
red grouper, red snapper, and yellowfin tuna. In terms of landing weight, Atlantic menhaden far surpassed
other commercial fish species in the Gulf, accounting for approximately 73 percent of the total weight of
landed commercial species in 2013 (Table 6.2). However, Atlantic menhaden accounted for only about 10
percent of the total value of the Gulf commercial fishery. The portion of commercial fishery landings that
occurred in nearshore and offshore waters of the Gulf States is presented in Table 6.3
In 2013, the eastern Gulf Region's seafood industry generated $527 million in sales in Alabama, $268 million
in sales in Mississippi, and $15 billion in sales in Florida Table 6.4). Florida generated the largest employment,
income, and value-added impacts, generating 78,000 jobs, $2.9 billion, and $5.1 billion, respectively. The
7 Updated information on fishery stock is available at: www.fisheries.noaa.gov/national/population-assessments/fishery-stock-status-
updates
8 Current information on US fisheries can be found at: www.nmfs.noaa.gov/sfa/fisheries_eco/status_of_fisheries/
ODC Evaluation Page 24 of 85
Ocean Era, Inc. - Velella Epsilon
-------
smallest income impacts were generated in Mississippi ($200 million) and the smallest employment impacts
were also generated in Mississippi (6,432 jobs) (NMFS, 2015).
Table 6.1 - Key Gulf Region Commercial Species or Species Groups
Shellfish
Finfish
Crawfish
Groupers
Blue Crab
Menhaden
Oysters
Mullets
Shrimp
Red Snapper
Stone Crab
Tunas
Table 6.2 - Total Weights and Values of Key Commercial Fishery Species in the Gulf Region in 2013 9
Species
Weight
(thousands of lbs)
Value
(Thousands of dollars)
% Weight
% Value
Menhaden
1,020,244
95,277
73.3
10.2
Shrimp
204,527
503,842
14.7
53.8
Blue crab
46,543
61,264
3.3
6.5
Oyster
19,230
76,729
1.4
8.2
Crayfish
19,823
16,593
1.4
1.8
Mullets
13,482
13,222
0.01
0.01
Stone crab
3,778
24,762
0.003
2.6
Groupers
7,280
23,396
0.005
2.5
Red snapper
5,286
20,493
0.004
2.2
Tuna
2,107
7,352
0.002
0.008
Total
1,392,364
936,660
-
-
Table 6.3 - Value of Gulf Coast Fish Landings by Distance from Shore and State for 2012 ($1,000) 10
State
Distance from Shore
0-3 miles 3-200 miles
Florida (Gulf)
$
64,727
$ 75,232
Alabama
$
15,870
$ 27,195
Mississippi
$
29,767
$ 19,509
In 2013 1.4 billion pounds of finfish and shellfish were landed in the Gulf Region. This was a 6.7 percent
decrease from the 1.5 billion pounds landed in 2004 and a 7.0 percent increase from the 1.3 billion pounds
9 NMFS, 2015.
10 https://www.st.nmfs.noaa.gov/commercial-fisheries/commercial-landings/other-specialized-programs/preliminary-annual-landings-
by-distance-from-shore/index
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 25 of 85
-------
landed in 2012. Finfish landings experienced a 9.6 percent decrease between 2012 and 2013 while shellfish
landings experienced a 1.6 percent decrease over the same period (Table 6.5).
From 2004 to 2013, species or species groups with large changes in landings include tunas (decreasing 46
percent), groupers (decreasing 39 percent), and oysters (decreasing 23 percent). Species or species groups
with large changes in landings between 2012 and 2013 include crawfish (increasing 66 percent), and red
snapper (increasing 24 percent) (NMFS, 2015).
The Deep-Water Horizon event had immediate effects on the Gulf fishing industry between April and
November 2010, with up to 40 percent of Federal waters being closed to commercial fishing in June and July
(CRS 2010). Portions of Louisiana, Alabama, Mississippi, and Florida state waters have also been closed. These
areas are some of the richest fishing grounds in the Gulf for major commercial species such as shrimp, blue
crab, and oysters, and as prices for these items have increased, imports of these species have likely taken the
place of lost Gulf coast production. NOAA continued to reopen areas to fishing once chemical tests revealed
levels of hydrocarbons or dispersants in commercial species were not of concern to human health.
It cannot be determined from these data whether the decreases in fin and shell fish landings were the result
of reduced stock sizes, changes in stock geographic distribution or changes in fishing effort, however studies
are currently on going and it is not known at this time whether there are long term affects to fisheries due to
the spill.
Table 6.4 - 2013 Economic Impacts of the Eastern Gulf Region Seafood Industry (thousands of dollars)11
State
Jobs
Landings Revenue
Sales
Income
Value Added
Alabama
$
12,090
$ 55,434
$ 526,767
$
200,494
$ 265,580
Mississippi
$
6,432
$ 46,618
$ 268,367
$
107,340
$ 138,779
Florida
$
78,378
$ 148,058
$ 15,319,435
$
2,878,309
$ 5,136,623
Table 6.5 - Total Landings and Landings of Key Species/Species Groups From 2010 to 2013 (thousands of
pounds)12
Landings
2010
2011
2012
2013
Finfish & other
810,649
1,472,798
987,374
1,092,148
Shellfish
261,419
319,752
305,821
300,216
Total landings
1,072,068
1,792,550
1,293,195
1,392,364
6.3 Recreational Fisheries
The NMFS (2015) estimates that in 2013, over 3.3 million recreational anglers took 25 million fishing trips in
the Gulf Region. The key fish species or species groups making up most of the recreational fishery in the Gulf
are listed in Table 6.6.
Of the three eastern Gulf states, western Florida had the highest number of anglers and fishing trips in 2013
(15.9 million), followed by Alabama (2.8 million), and Mississippi (1.8 million) (Table 6.7). Almost 67 percent
11 NMFS, 2015
12 NMFS, 2015
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 26 of 85
-------
of the fishing trips in the Gulf coast left out of west Florida, followed by Alabama (7 percent), and Mississippi
(5 percent). 41.8 percent of the total recreational fish landings (by weight) in the Gulf occurred in Florida,
12.8 percent 33 in Alabama, and 5.3 percent in Mississippi.
In Mississippi, nearly all landings were made in inland waters (98.6 percent). While the inland catch was
important in Alabama (50.0 percent) and Florida (44.0 percent), the offshore catch was larger in these states,
with 34.1 percent of the total catch landed up to 5 km (3 mi) from shore, and 16 percent at more than 5 km
(3 mi) in Alabama and 28.7 percent at less than 16 km (10 mi), and 27.3 percent at more than 16 km (10 mi)
in Florida.
Recreational fishing contributes to the Gulf state economies mainly through employment, expenditures
(fishing trips and durable good), and sales. Table 6.8 shows the economic impacts of recreational fisheries by
Gulf state. Recreational fishing activities generated over 87,000 full- and part-time jobs in Alabama,
Mississippi and West Florida, and over $10.0 billion in sales.
Table 6.6 - Key Gulf Region Recreational Species 13
Atlanta Croaker Gulf and Southern Kingfish
Sand and Silver Seatrout Spotted Seatrout
Sheepshead porgy Red Drum
Red Snapper Southern Flounder
Spanish Mackerel Striped Mullet
Table 6.7 - Estimated Number of People Participating in Eastern Gulf Marine Recreational Fishing in 2013
(thousands)14
Location
Coastal
Non-coastal
Out of state
Total
West Florida
1,813
NA
2,538
4,351
Alabama
279
224
549
1,050
Mississippi
171
67
101
339
Gulf Total
2,263
291
3,098
5,740
Table 6.8 - 2013 Economic Impacts of Recreational Fishing Expenditures in the Eastern Gulf (thousands of
dollars)15
Location
Trips
Jobs
Sales
Income
Value Added
Alabama
$ 2,862
$ 10,163
$ 927,409
$ 358,769
$ 569,144
Mississippi
$ 1,761
$ 1,583
$ 146,333
$ 53,602
$ 87,684
West Florida
$ 15,949
$ 76,236
$ 9,086,311
$ 3,423,836
$ 5,341,420
Total
$ 20,572
$ 87,982
$ 10,160,053
$ 3,836,207
$ 5,998,248
13 NMFS, 2015
14 NMFS, 2015
15 NMFS, 2015
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 27 of 85
-------
7.0 Coastal Zone Management Consistency and Special Aquatic Sites
This chapter addresses two of the 10 ODC: (5) The existence of special aquatic sites including, but not limited
to marine sanctuaries and refuges, parks, national and historic monuments, national seashores, wilderness
areas and coral reefs, and (8) Any applicable requirements of an approved Coastal Zone Management plan.
7.1 Coastal Zone Management Consistency
The Coastal Zone Management Act (CZMA) requires that any Federally-licensed or permitted activity
affecting the coastal zone of a state that has an approved coastal zone management program (CZMP) be
reviewed by that state for consistency with the state's program (16 USC § 1456(c)(A) Subpart D). Under the
Act, applicants for Federal licenses and permits must submit a certification that the proposed activity
complies with the state's approved CZMP and will be conducted in a manner consistent with the CZMP. The
state then has the responsibility to either concur with or object to the consistency determination under the
procedures set forth by the Act and their approved plan.
Consistency certifications are required to include the following information (15 CFR § 930.58): "A detailed
description of the proposed activity and its associated facilities, including maps, diagrams, and other technical
data; a brief assessment relating the probable coastal zone effects of the proposal and its associated facilities
to relevant elements of the CZMP; a brief set of findings indicating that the proposed activity, its associated
facilities, and their effects are consistent with relevant provisions of the CZMP; and any other information
required by the state."
The states of Mississippi, Alabama, and Florida have federally approved CZMP. Each Gulf state has specific
requirements in their CZMA plans that outline procedures for determining whether the permitted activity is
consistent with the provision of the program.
Discharges covered by the proposed permit will occur in Federal waters outside the boundaries of the coastal
zones of the State of Florida. However, because these discharges could create the potential for impacts on
state waters, consistency determinations for the individual NPDES permit will be prepared by the proposed
project and submitted to the State of Florida. The following summaries describe the requirements of the
state's management plan for consistency determination. The permit applicant must provide the necessary
data and information for the state to determine that the proposed activities comply with the enforceable
policies of the states' approved program, and that such activities will be conducted in a manner consistent
with the program.
7.2 Florida Coastal Management Program
The Florida Coastal Management Program (FCMP) was approved by NOAA in 1981 and is codified at Chapter
380, Part II, F.S. The State of Florida's coastal zone includes the area encompassed by the state's 67 counties
and its territorial seas. The FCMP consists of a network of 24 state statutes administered by eight state
agencies and five water management districts.
The review of federal activities is coordinated with the appropriate state agency. Each agency is given an
opportunity to provide comments on the merits of the proposed action, address concerns, make
recommendations, and state whether the project is consistent with its statutory authorities in the FCMP.
Regional planning councils and local governments also may participate in the federal consistency review
process by advising the Department of Economic Opportunity (DEO) on the local and regional impact of
proposed federal actions. Comments provided by regional planning councils and local governments are
considered by the DEO in determining whether the proposed federal activity is consistent with specific
sections of Chapter 163, Part II, F.S., that are included in the FCMP. If a state agency determines that a
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 28 of 85
-------
proposed activity is inconsistent, the agency must explain the reason for the objection, identify the statutes
the activity conflicts with and identify any alternatives that would make the project consistent.
Federal consistency reviews are integrated into other review processes conducted by the state depending on
the type of federal action being proposed. The Florida State Clearinghouse administered by the Florida
Department of Environmental Protection (FDEP) Office of Intergovernmental Programs, is the primary
contact for receipt of consistency evaluations from federal agencies. The Clearinghouse coordinates the
state's review of applications for federal permits other than permits issued under Section 404 of the CWA
and Section 10 of the Rivers and Harbors Act. As the designated lead coastal agency for the state, the FDEP
communicates the agencies' comments and the state's final consistency decision to federal agencies and
applicants for all actions other than permits issued under CWA Section 404 and Section 10 of the Rivers and
Harbors Act.
7.3 Special Aquatic Sites
Special aquatic sites are "geographic areas, large or small, possessing special ecological characteristics of
productivity, habitat, wildlife protection, or other important and easily disrupted ecological values. These
areas are generally recognized as significantly influencing or positively contributing to the general overall
environmental health or vitality of the entire ecosystem of a region" (40 CFR § 230.3). Areas of high relief
ridges and outcroppings occur on the west Florida Shelf (Figure 7-1). These include the Madison-Swanson
Marine Reserve, Florida Middle Grounds, Pulley Ridge, Steamboat Lumps Special Management Area, and
Sticky Ground Mounds (BOEM, 2013).
7.3.1 Madison-Swanson/Steamboat Lumps Marine Reserves/The Edges
Madison-Swanson and Steamboat Lumps Marine Reserves are at two ends of a line of ridges beginning north
of Tampa Bay along the 100 m isobath. Madison-Swanson and Steamboat Lumps were protected initially in
2002 and are now established Marine Protected Areas; no-take marine reserves sited on gag spawning
aggregation areas where all fishing is prohibited (219 square nautical miles). With the addition of The Edges,
during seasonal closures, Madison-Swanson and Steamboat Lumps cover 600 square miles.
7.3.2 Florida Middle Grounds HAPC (1984)
These reefs consist of a series of both high and low relief limestone ledges and pinnacles that exceed 15
meters (49 feet) in some areas. The area consists of roughly 348 nm2 of this hardbottom region 150
kilometers (93 miles) south of the panhandle coast and 160 kilometers (99 miles) northwest of Tampa Bay.
It is a Habitat Area of Particular Concern protected by preventing use of any fishing gear interfacing with
bottom.
7.3.3 Pulley Ridge
Pulley Ridge is the deepest known photosynthetic coral reef off the continental United States. The area
contains a near pristine, deep water reef characteristic of the coral reefs of the Caribbean Sea which are located
in the southern quadrant of Pulley Ridge. These coral reefs occupy an area of about 111 square nautical miles.
In 2005, a section of Pulley Ridge was designated as Habitat Area of Particular Concern (HAPC), which
prohibited bottom anchoring by fishing vessels, bottom trawling, bottom longlines, buoy gear, and all
trap/pot use in the area.
7.3.4 Sticky Ground Mounds
Shelf-margin carbonate mounds in water depths of 116-135 m in the eastern Gulf along the central west
Florida shelf, off Tampa Bay. Various species of sessile attached reef fauna and flora grow on the exposed
hard grounds. Some taller species (e.g., sea whips and other gorgonians) appear to survive this intermittent
sand movement and accretion. Surveys on the southwest Florida Shelf revealed that the biotic cover on the
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 29 of 85
-------
live bottom patches is generally low and that the patches tend to be dominated by either algae or encrusting
invertebrates (Woodward Clyde Consultants and CSA, 1984).
Figure 7.1 - High Relief Live Bottom Areas in the Central and Eastern Gulf16
PENSACOLA
Madison-Swanson
Marine Reserve
Florida
Middle /
Grounds
Steamboat Lumps
Marine Reserve
Sticky Ground
Mounds \
Eastern
Planning
Area
' / 1 Live Bottom (Low Relief) Stipulation Blocks
111111 Live Bottom (Pinnacle Trend) Stipulation Blocks
Proposed Sale Area
Representative Eastern Planning Area
High-Relief Live Bottoms
200 Kilometers
200 Miles
• TALLAHASSEE
PANAMA CITY
£ FLORIDA
• TAMPA
Central
Planning
Area
• NAPLES
16 BOEM, 2015
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 30 of 85
-------
8.0
Federal Water Quality Criteria and Florida Water Quality Standards
Factor 10 of the 10 factors used to determine no unreasonable degradation requires the assessment of
Federal marine water quality criteria and applicable state water quality standards (WQS).
8.1 Federal Water Quality Criteria
Pursuant to CWA § 303(c), the implementing regulations in 40 CFR § 131 establish the requirements for states
and tribes to review, revise and adopt WQS. The regulations also establish the procedures for EPA to review,
approve, disapprove and promulgate WQS pursuant to the CWA. State WQS apply within the jurisdictional
waters of the state. For marine waters, state WQS apply within three nautical miles of shore. There are no
WQS that apply for marine waters in the Gulf seaward of the three nautical mile boundary.
Section 304 of the CWA requires EPA to develop criteria for ambient water quality that accurately reflect the
latest scientific knowledge on the impacts of pollutants on human health and the environment.17 EPA designs
aquatic life criteria to protect both freshwater and saltwater organisms from short-term and long-term
exposure. Aquatic life criteria are based on how much of a chemical can be present in surface water before
it is likely to harm plant and animal life. EPA's Section 304(a) criteria are not laws or regulations; they are
guidance that states or Tribes may use as a starting point when developing their own WQS.
8.2 Florida Water Quality Standards
The proposed facility will be located approximately 45 miles seaward of Sarasota Bay, Florida, beyond the
jurisdictional waters of the State of Florida. The WQS promulgated by Florida are not applicable to the
proposed project because the project is within federal waters of the Gulf; however, some information about
Florida's WQS is presented below.
WQS for the surface waters of Florida are established by the Department of Environmental Regulation in the
Official Compilation of Rules and Regulations of the State of Florida, Chapter 62-302: Surface Water Quality
Standards (Effective March 27, 2018).18 Minimum criteria apply to all surface waters of the state and require
that all places shall at all times be free from discharges that, alone or in combination with other substances
or in combination with other components of discharges, cause any of the following conditions.
Settleable pollutants to form putrescent deposits or otherwise create a nuisance
Floating debris, scum, oil, or other matter in such amounts as to form nuisances
Color, odor, taste, turbidity, or other conditions in such degree as to create a nuisance
Acute toxicity (defined as greater than 1/3 of the 96-hour LC50)
Concentrations of pollutants that are carcinogenic, mutagenic, or teratogenic to human beings or
to significant, locally occurring wildlife or aquatic species
Serious danger to the public health, safety, or welfare.
These general criteria of surface water apply to all surface waters except within zones of mixing. A mixing
zone is defined as the surface water surrounding the area of discharge "within which an opportunity for the
mixture of wastes with receiving waters has been afforded." Effluent limitations can be set where the
analytical detection limit for pollutants is higher than the limitation based on computation of concentration
in the receiving water.
17 Current federal water quality criteria are found here: www.epa.gov/wqc/national-recommended-water-quality-criteria-aquatic-life-
criteria-table
18 https://floridadep.gov/dear/water-quality-standards
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 31 of 85
-------
The antidegradation policy of the standards that applies in Florida waters requires that new and existing
sources be subject to the highest statutory and regulatory requirements under Sections 301(b) and 306 of
the CWA. In addition, water quality and existing uses of the receiving water shall be maintained and violations
of WQS shall not be allowed.
As discussed in Section 3, all point source wastewater discharges are subject to a NPDES permit. Potential
impacts from fish wastes will be determined by water quality and benthic monitoring to ensure that no
unreasonable degradation of the marine environment will occur in accordance with Section 403 of the CWA.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 32 of 85
-------
9.0 Potential Impacts
This section summarizes the potential impacts to receiving waters of the Gulf that might occur as a result of
the discharges from the proposed project. Also discussed in this section is the transport and persistence
(Factor 2) and the toxicity and bioaccumulation potential (Factors 1 and 6) of pollutants discharged from the
proposed facility.
9.1 Overview
Net pen aquaculture and its resultant discharges may have effects on water and sediment quality and the
plant and animal communities living in the water column and those in close association with, on or in the
sediments. The major discharges, uneaten fish food and fish metabolic wastes, are likely to have their
greatest impacts on the water column, benthos and related communities.
The two major factors which determine the geographic distribution and severity of impacts of net pens on
the water column, seafloor sediments and benthic communities are farm operations management and siting.
Farm Operations Management
1. Loading. The biomass of fish reared in the pens is proportional to the amount of organic matter
deposited from the pens. The greater the density offish, the more concentrated the deposition of
organic waste.
2. Pen size. Larger pens, with the same loading, deposit sediments over a relatively smaller area (Earll
et al 1984). Thus, the effects are more concentrated, however, the size of the area affected is less.
3. Pen configuration. Pen configuration and orientation to the predominant currents can significantly
affect the dispersion of wastes.
4. Feed type. Different feeds have different settling rates. Slower rates allow greater dispersion. In
addition, feed that has lower carbon and nitrogen levels and higher digestibility will produce less
organic matter on the bottom.
5. Feeding method. Feeding methods can affect both wastage of feed and utilization of that feed by the
fish. In one study, hand feeding resulted in 3.6 percent wastage, and up to 27.0 grams per meter
squared per day (g/m2/day) organic matter deposition on the bottom. The use of automatic feeders
resulted in wastage of 8.8 percent and a maximum deposition of 88.1 g/m2/day (Cross, 1988).
Siting
1. Water depth and current velocity. In deeper water and faster currents, the dispersion of wastes will
be greater.
2. Bottom current velocity. High bottom current velocities can erode and disperse resuspended
sediments regardless of dispersion in the total water column.
3. Bottom sediments and community. The benthic community will also affect the impact. Areas of high
biological productivity may be able to assimilate higher organic deposition. However, adverse impacts
may have greater significance due to the importance of such productive areas. Conversely, areas
having few organisms may have less assimilative capacity, but creation of an azoic zone may have less
effect on the biological community
9.2 Water Column Impacts
The water quality around coastal fish farms is affected by the release of dissolved and particulate inorganic
and organic nutrients. Water column effects around fish farms include a decrease in dissolved oxygen and
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 33 of 85
-------
increases in biological oxygen demand, and nutrients (P, total C and organic and inorganic N) (Penczak et al.,
1982). Degradation of water quality parameters is greatest within the fish culture structures and improves
rapidly with distance from holding pens. Recent studies have documented only limited water column impacts
due to rapid dispersal (Holmer, 2010). The health of the fish stocks is a self-limiting control on water column
pollution. Another review found that though the probability of any measurable impact from an offshore farm
appears to significantly decrease with distance from the farm, such information suffers from a general lack
of robustness and should be quantified with better systematic and standardized reporting with respect to
physical farm characteristics (Froehlich et. a I., 2017).
9.2.1 Turbidity
Turbidity, an indication of water clarity, may be affected by fish farming operations. The loss offish food and
feces is the largest source of increase in turbidity around net pens. Net cleaning can also significantly increase
turbidity down current of net pens. Turbidity will likely be most affected by cage siting with current velocities
and tidal influence the major factors. A study in the Puget Sound reported that floating net pens did not
affect turbidity (NMFS 1983). Turbidity ranged from 0.5 to 2.0 NTU throughout the study, but measurements
were not taken during net cleaning. In other studies, suspended solid concentrations and light attenuation
(due to turbidity) were found to be insignificant or localized.
9.2.2 pH
The effects offish farming on water column pH was studied by Pease (1977) who reported that a net-pen
facility in a poorly flushed, log rafting area (Henderson Inlet, Washington) did not affect pH. Pease also
reported that tidal factors were the primary factor regulating pH at all sites.
9.2.3 Temperature
The operation of floating net pens would not affect water temperatures in the Gulf. Net pens have no
features that would measurably change heat loss or heat gain in surrounding waters.
9.2.4 Fecal Coliforms
Fecal coliform bacteria are produced in the digestive tracts of warm-blooded animals. Net pens do not
directly affect ambient (existing) fecal coliform concentrations in surrounding waters because fecal coliforms
are not produced in fish. However, fecal coliform levels could indirectly increase near net pens from increased
marine bird and mammal activity or human activity.
9.2.5 Nutrients
Nutrient addition to the Gulf is of concern because they contribute to certain harmful algal blooms (HABs).
HABs are on the rise in frequency, duration, and intensity in the Gulf, largely because of human activities
(Corcoran, et.al., 2013). Of the more than 70 HAB species occurring in the Gulf, the best-known is the red
tide organism, Karenia brevis, which blooms frequently along the west coast of Florida. Macronutrients,
micronutrients and vitamins characteristic offish farms are growth-promoting factors for phytoplankton. The
primary nutrients of interest in relation to net pens are nitrogen and phosphorus; both may cause excess
growth of phytoplankton and lead to both aesthetic and water quality problems. Generally, in marine waters,
phytoplankton growth is either light or nitrogen limited, and phosphorus is not as critical a nutrient as it is in
fresh water (Ryther and Dunstan, 1971; Welch, 1980). However, it has been shown that because nutrient
fluctuations in the Gulf can be significant due to the large inputs from river systems, both nitrogen limitation
and phosphorus limitation can happen in different locations, but during the same time frame (Turner and
Rabalais, 2013)
Nitrogen may be categorized as: (1) inorganic (nitrate, nitrite and ammonia and nitrogen gas); and (2) organic
(urea and cellular tissue). Most of the organic matter in waste food and feces from net pens is composed of
organic carbon and nitrogen (Liao and Mayo, 1974; Clark et a I., 1985). About 22 percent of the consumed
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 34 of 85
-------
nitrogen is retained within the fish tissue and the remainder (78 percent) is lost as excretory and fecal matter
(Gowen and Bradbury 1987). In a summary of nitrogen budgets in marine cage aquaculture, Islam (2005)
reported that 68-86 percent of the nitrogen input as feed is eventually released to the environment. In a
recent study, it was determined that about 63 percent of nitrogen fed at a rainbow trout Oncorhynchus
mykiss farm was lost as dissolved nitrogen (NorSi et al., 2011).
Approximately 87 percent of the metabolic waste nitrogen is in the dissolved form of ammonia and urea; the
remainder (13 percent) is lost with the feces (Hochachaka, 1969). Salmon will produce approximately 0.22 to
0.28 grams of all forms of dissolved nitrogen per day per kilogram of fish produced annually (Ackefors and
Sodergren, 1985; Penczak et al., 1982; Warren-Hansen, 1982). Ammonia and urea are essentially
interchangeable as phytoplankton nutrients. Immediately downstream of most net pens (5-30 m) the
concentration of ammonia diminishes greatly. This decrease is probably due to the natural microbial process
of nitrification (oxidation of ammonia to nitrites and nitrates). Rapid rates of nitrification are expected in any
well-oxygenated aquatic environment (Harris 1986). The effects of these factors on phytoplankton near fish
farms are variable and not enough scientific evidence is available to suggest that macronutrients and
micronutrients from fish farming, or the proposed project, can be directly related to the occurrence of red
tides.
9.2.6 Ammonia Toxicity
Toxic chemicals would not be introduced into the net pens from fish stock or food. Ammonia in the un-ionized
form (NH3) is toxic to fish at high concentrations depending on water temperature and pH (EPA, 1986). High
ammonia levels in fish excrement have been shown to raise ambient (existing) ammonia concentrations.
Normal concentrations of ionized and un-ionized ammonia in Gulf waters are very low, with some variability.
A small percentage of the ammonia originating from net pens typically about 2 percent, will be of the toxic,
un-ionized form.
Near-field studies in Washington state (Milner-Rensel, 1986; Rensel, 1988 b,c) have shown increased
concentrations of ammonia immediately downstream orwithin the net pens. Total ammonia values typically
have increased from 3 to 55 percent above the low background levels. The highest observed concentrations
were only a small fraction of the maximum four-day, chronic exposure level recommended by EPA (1986). A
long-term study, under worst-case conditions in southern Puget Sound, found that the greatest
concentration of total ammonia observed at any time was 0.176 mg/l, equivalent to 0.006 mg/l un-ionized
ammonia, well below chronic exposure threshold (Pease, 1977).
In summary, increases in dissolved nitrogen (including ammonia) are typically seen within salmon net pens.
Immediately downstream, nitrogen or ammonia levels may also be elevated compared to ambient, upstream
values. However, results are variable (Price and Morris, 2013). In some cases, concentrations were greater
or much less than expected compared to predicted values based on freshwater hatchery data. However, even
within the net pens, toxic concentrations of un-ionized ammonia were not approached. Net pen fish culture
in open Gulf waters will be characterized by relatively large volumes of water passing through cages per unit
offish production. This results in much greater dilution of waste products such as ammonia in net pens when
compared to freshwater hatcheries or municipal sewage discharges (Weston, 1986).
9.2.7 Phosphorus
Although nitrogen is generally considered to be the limiting macro-nutrient in many ocean waters, increasing
phosphorus levels in coastal waters due to anthropogenic sources is also of concern because some marine
systems can be phosphorus limited. Increased phosphorus may, along with nitrogen, contribute to algal
blooms and coastal eutrophication. Like nitrogen, the principal sources of phosphorus from fish farms are
uneaten food, fecal matter and metabolic wastes. A review of phosphorus budgets of marine cage
aquaculture reported that an average of 71.4 percent of the phosphorus in feed was released into the
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 35 of 85
-------
environment, the amounts depending on species cultured, feed type, and feeding efficiency (Islam, 2005).
Though fewer studies looked at phosphorus impacts, of those that did, a number showed measurable
increases in dissolved phosphorus around net pens, several showed statistically significant increases (Price
and Morris, 2013).
9.2.7 Dissolved Oxygen
Dissolved oxygen consumption by fish, and by microbial decomposition offish wastes and excess food, could
significantly reduce water column dissolved oxygen concentrations near the pens. Most of the microbial
decomposition is associated with solids that settle to the bottom (Institute of Aquaculture, 1988). Thus, the
greatest potential for oxygen consumption would be from fish respiration near the surface and microbial
decomposition near the bottom.
The total effect of oxygen consumption from net-pen operations on dissolved oxygen concentrations near
the pens is highly variable. The loss of dissolved oxygen depends on the water exchange rate near pens, fish
density, and fish feeding rate. If the water exchange rate near the pens is high, there will be less reduction of
dissolved oxygen. If the fish density and fish feeding rate are high, there will be increased dissolved oxygen.
In general, the dissolved oxygen requirements offish raised in net pens limit the impact net pens can have
on the environment. The lowest oxygen levels caused by net pens are likely to occur within the net pens and
immediately down current. Thus, the impact of low dissolved oxygen is likely to affect the net-pen operation
before having an effect on the surrounding environment.
9.3 Organic Enrichment Impacts to Seafloor Sediments
Numerous studies have shown that organic enrichment of the seabed is the most widely encountered
environmental effect of culturing fish in cages (Karakassis et a I., 2000, Karakassis et a I., 2002, Price and
Morris, 2013). The spatial patterns of organic enrichment from fish farms varies with physical conditions at
the sites and farm specifics and has been detected at distances from meters to several hundred meters from
the perimeter of the cage array (Mangion et a I., 2014). Studies offish farms in the Mediterranean showed
that the severe effects of organic inputs from fish farming on benthic macrofauna are limited to up to 25 m
from the edge of the cages (Lampadariou et a I., 2005) although the influence of carbon and nitrogen from
farm effluents in sea floor can be detected in a wide area about 1,000 m from the cages (Sara et a I., 2004).
The impacts on the seabed beneath the cages were found to range from very significant to relatively
negligible depending on sediment type and the local water currents, with silty sediments having a higher
potential for degradation.
Sedimentation rates are often 1-3 orders of magnitude higher at fish farms compared to unaffected areas of
the coast (Brown et a I., 1987; Hall et a I., 1990). Weston and Gowen (1988) found the greatest sediment
deposition occurred in the direction of the dominant current. Sediment traps under the pens estimated
deposition of 52.1 kilograms dry weight per meter squared per year (kg dry wt./m2/yr) and 29.7 kg dry
wt./m2/yr at the pen perimeter.
Sedimentation effects from net pens are the result of two major factors, additional particulate organic input
and inorganic sediment deposition. An additional factor contributing to sedimentation is organic matter that
grows on nets and is dislodged from the net during cleaning. This source contributes relatively little to the
total sedimentation generated by a net-pen operation (Weston, 1986). The organic input from these sources
affects both the chemical composition of the sediments and the responses of the organisms in the sediment
(Pearson and Rosenberg, 1978). A review of more recent studies pertaining to nutrient and organic carbon
loading to sediments from fish farms around the world can be found in Price and Morris (2013).
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 36 of 85
-------
One of the main impacts of organic enrichment to seafloor sediments is the stimulation of sediment
metabolism, i.e., increased microbial activity, sediment oxygen demand and nutrient release (Holmer, 1991).
High organic loading to the sea floor may result in the development of anoxic and reducing conditions and
the production of toxic gases, i.e., ammonia, methane and hydrogen sulfide (H2S).
In undisturbed sediments, oxygen is only able to penetrate a short distance depending upon sediment
porosity, bioturbation (activity of burrowing organisms), and current velocity, which controls the rate at
which oxygen is renewed at the sediment surface. Oxygenated sediments are typically light tan to light grey
in color. Below this oxic layer, sediments are oxygen depleted (anoxic). Anoxic sediments are characterized
by their dark black color, and the production of hydrogen sulfide gas. With increasing organic loading, the
demand for oxygen for microbial processes and reoxidation of reduced mineralization products increases.
Sediment oxygen demand (SOD) near fish farms can exceed the diffusive oxygen influx and the anoxic layer
moves closer to the surface (Brown et a I., 1987). Studies have shown that sediment oxygen demand of
sediments enriched by fish-farming activities can be 2-5 times higher than in control areas (Hargrave, et a I.,
1993). In these cases, the organic material often forms a layer over the original sediments. In stagnant areas
of poor circulation, oxygen demand by the anoxic sediments will reduce the dissolved oxygen in the overlying
water. Anaerobic metabolism of sediments becomes important in organic matter decomposition near farms
(Hall et a I., 1990). Studies show that soleplate reduction is the terminal process for organic oxidation.
Anaerobic decomposition of the organic matter under these conditions may also lead to production of
methane in sufficient quantities to produce visible bubbles at the surface. At this point hydrogen sulfide will
reach concentrations that allow its distinctive "rotten egg" smell to be detected in the water. H2S is highly
toxic, making these sediments toxic, and at higher concentrations can lead to mortality offish in pens.
The oxidation-reduction (redox) potential (positive = oxic; negative = anoxic) gives a relative indication of the
degree of enrichment. Negative oxidation-reduction (redox) values, indicating a strong possibility of
anaerobic conditions and the production of H2S, are common in sediments near and beneath net pens (Brown
et a I., 1987). As organic matter continues to accumulate oxygen penetration into sediments are decreased
and redox potential values become more negative. Mats of white supplied oxidizing bacteria Beggiatoa spp.
covering the seafloor beneath salmonid cages have been observed (Hall et al. 1990).
It is estimated that only about 10 percent of the organic matter deposited from net pens each year is broken
down through microbial decomposition (Aure and Stigebrandt, 1990), and decomposition has been shown
to be inversely related to accumulation. Of the total carbon, nitrogen and phosphorous deposited to
sediments, around 79 percent, 88 percent and 95 percent respectively will accumulate and become
unavailable to the environment. Release of phosphorous to the environment is insignificant when deposits
are greater than 7 cm. Nitrogen mineralization is very slow in normally anaerobic sediments beneath net
pens where bioturbation and epifaunal reworking of sediments is minimized. In some studies, it was shown
that nitrogen cycling, nitrification (converting ammonium to nitrate) and denitrification (converting nitrate
to N2 gas) ceased. Most of the nitrogen is released to the water as ammonium and dissolved organic nitrogen.
A review of 41 papers (Kalantzi and Karakassis, 2006) covering a wide range of cultured species, habitats, site
characteristics and farm management practices concluded that their analysis suggests that the impact radius
at fish farms generally decreases with increased depth, at low latitudes and over fine sediment. The authors,
however, state that applying common standards over large geographic areas is challenging due to the
complex interplay of site characteristics among the studies they reviewed. A 2012 study of a farm in Norway
in 190 meters of water showed that despite deep water and low water currents, sediments underneath the
farm were heavily enriched with organic matter, resulting in stimulated biogeochemical cycling concluding
that water depth alone may not be sufficient (Valdemarsen, et.al., 2012). In another review of 64 studies of
benthic fish farm impacts, Giles (2008) developed a quantitative assessment of the relationships between
impact parameters and site and farm characteristics. The analysis showed that benthic impact was a function
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 37 of 85
-------
offish density, farm volume, food conversion ratio, water depth, current strength and sediment mud content.
The analysis also suggested that fish farm impacts were confined to a radius of about 40 to 70 m around the
farms, however, the inability to satisfactorily model parameters as a function of distance from farms
demonstrated the complexity of the spatial distribution of the farms studied.
9.4 Organic Enrichment Impacts to Benthic Communities
The deposition of uneaten fish feed and feces may affect benthic communities in several ways. The
accumulation of organic and inorganic particulates may impact benthic flora and fauna. Significant changes
in the proportion of the fine sediment fractions can alter the microstructure of the habitat supporting
macroinfauna and meiofauna communities resulting in changes in both structure and function. High
sedimentation rates may interfere with feeding mechanisms of deposit and filter feeders. Benthic epifauna
and flora may be buried at very high rates of sedimentation. Sedimentation rates are often 1-3 orders of
magnitude higher at fish farms compared to unaffected areas (Brown et a I., 1987; Hall et a I., 1990; Holmer,
1991).
Sedimentation from net pens decreases sediment oxygen levels by increasing the demand for oxygen, and
by decreasing both diffusion and water flow into the interstitial spaces of the sediment. As increasing
amounts of fine sediment accumulate, the depth to which oxygen penetrates is reduced and the underlying
sediment layers become devoid of oxygen (anoxic) and unable to support animal life. The only organisms
found in such sediments will be those that have access to the surface waters for respiration via burrows or
siphons, and anaerobic bacteria, which derive energy from sources other than oxygen.
Depending on the rates of organic loading, community structure near net pens may become dominated by
pollution tolerant species or fauna may disappear entirely. Impact studies show variable results with some
showing a clear correlation between the deposition of fish wastes and community changes (Brown et a I.,
1987). Pearson and Rosenberg (1978) present a comprehensive review of the impacts of organic enrichment
from a variety of natural and man-made sources on bottom sediments and the associated benthic
community. The authors show that benthic communities tend to respond along a gradient of organic loading
with effects most pronounced near the source and decrease progressively with increasing distance.
In undisturbed sediments a stable, diverse benthic community exists comprised of relatively large epibenthic
(surface dwelling) organisms, smaller burrowing organisms (< 0.5 mm) comprising the macroinfauna and the
meiofauna, smaller (< 0.064 mm) that occupy the interstitial spaces between sediment particles. As organic
matter is introduced into an undisturbed environment, it provides an additional source of nutrition for the
benthic organisms. This additional organic matter benefits the existing filter- and deposit- feeders, and
encourages colonization by additional species. Thus, both species diversity and biomass (total weight) of the
benthic organisms increases, and the benthic community is enhanced. The authors refer to this as the
"transition zone."
Earll et al. (1984) observed benthic conditions below 25 net-pen facilities in Scotland. He noted that the redox
potentials were reduced to a distance of 20 to 30 m from the pens and that Beggiatoa first appeared 10 to
15 m from the pen perimeter. Outside this zone, the sediment surface appeared normal and was light brown
in color with a thin covering of diatoms. Predator species such as crab, flatfish, nudibranchs, and anenomes
were abundant. Scallops, starfish, and sea cucumbers were also observed. Stewart (1984) noted that organic
loading, carbon:nitrogen ratios, and redox potentials were essentially normal beyond 40 m of a pen site. He
concluded that the transition zone extended 37 to 100 m from the pens.
High species abundance and diversity, representing both pre-existing species and newly colonized species,
were found in a zone 15 to 120 m from pens by Brown et al. (1987). Gowen et al. (1988) observed that total
organic carbon, redox potentials and dissolved oxygen levels were normal beyond 15 m of the pens, and that
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 38 of 85
-------
opportunistic species dominated the zone between 15 and 120 m, with the inner boundary of the transition
zone being 20 to 25 m from the pen boundary.
In studies conducted by Weston and Gowen (1988) it was estimated that normal benthic communities
extended to within 150 to 450 m of the pens. Mobile predators are also abundant in this area, including flat
fish (Pease 1984) and crab (Earll et. al., 1984; Cross, 1988). Weston and Gowen (1988) concluded that changes
in the biological community extended beyond the zone where chemical changes were detectable. Weston
(1990) studied benthic infauna response to organic enrichment at a large Puget sound fish farm. Species
richness, biomass and size of organisms decreased near the cages. Total abundance of individuals increased
when nematodes (pollution tolerant species) were included. Suspension and deposit feeders found at 450 m
either disappeared or were greatly reduced near cages.
Pearson and Rosenberg (1978) observed that as the level of organic input continues to increase, the
sediments become progressively dominated by various opportunistic deposit feeders which are able to
flourish under these conditions. The most notable deposit feeder is the small, common polychaeta worm
Capitella capitata, indicative of organic enrichment. Under these conditions, the abundance of these
opportunistic species can reach very high densities, to the exclusion of other species. Elimination of the
larger, deeper borrowing animals further reduces the ability of oxygen to penetrate the sediments.
Gowen et al. (1988), and Brown et al. (1987) observed that the area between 3 and 15 m was almost
exclusively dominated by opportunistic polychaete worms, especially Capitella capitata. The total number of
species in this zone was about 20 percent of that in undisturbed sediments. The number of individuals,
however, was 2 to 3 times normal with total biomass slightly below normal. All of the organisms were
polychaete worms, with Capitella capitata representing 80 percent of the total organisms. Weston and
Gowen (1988) observed increased concentrations of carbon, nitrogen, and reduced redox potentials
between 15 and 60 m down current (east) from net pens in the Puget Sound. The abundance of organisms
was approximately 4 times greater than background at the pen perimeter and declined to background levels
at about 45 m, with Capitella capitata the dominant species. Biomass was reduced to about 45 m and
increased moderately between 90 and 150 m. Normal conditions were reached between 150 and 450 m from
the pens. Pease (1984) reported that geoduck (bivalve mollusk) abundance increased in this area away from
the pens. No geoducks were found in the area occupied by Bogota. However, in a more recently developed
site in British Columbia, geoducks were observed in within the more distant area occupied by Beggiotoa
(Cross 1988).
At very high rates of organic sedimentation, few species can survive. At this point, the anoxic layer reaches
the sediment surface, depriving the animals of oxygen and exposing them to toxic H2S. In these sediments,
the surface is black and devoid of any animals (azoic). Gowen et al. (1988) estimated that input of organic
matter at rates greater than about 8g carbon/m /day resulted in production of methane and azoic conditions.
At low concentrations, H2S can reduce fish health through gill damage and at higher concentrations be toxic
to fish in the pens above the sediments. Such affects have only been reported in stagnant areas with little
water circulation.
Azoic zones have been reported under most net pens, though their presence depends on the size (amounts
of wastes produced) of the fish farm (Weston and Gowen 1988) and water circulation beneath and around
cages (Weston 1986; Institute of Aquaculture 1988). The absence of Beggiotoa under the pens observed by
Earll et al. (1984) was attributed to its need for both oxygen from surface water and H2S from the anoxic
sediments. No live animals were observed in this zone; however, occasional dead starfish, nudibranchs and
sea cucumbers were observed on the surface. Gas bubbles (methane) were evident in the sediment and
redox potentials were severely depressed. Stewart (1984) observed these conditions to extend to about 3 m
from the pen perimeter, observed a zone of dark, black sediments under most net pens observed. Similar
observations are reported by Gowen et al., (1988) extending 3 m from the pens. In this zone, total organic
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 39 of 85
-------
carbon levels are about twice background levels and redox potentials were consistently less than -100 mV,
despite seasonal variations. Dissolved oxygen in the overlying water was reduced and gas bubbles were
observed. Hall and Holy (1986) measured chemical changes below a small net pen complex. Both total organic
carbon and nitrogen concentrations were increased ten-fold above background levels, and benthic oxygen
consumption was increased 12 to 15 times. Deposition underthese pens was 50 to 200 g/m2/day total solids,
about 20 times higher than background.
The effects of organic enrichment of the sediments begins quickly after installation and operation of the net
pens. Weston and Gowen (1988) observed only limited changes in the community at the Squaxin Island site
after 18 months of operation. Ritz et al. (1989) saw a decline in macroinfauna signifying moderately disturbed
conditions (biomass>abundance) beneath salmonid cages in Tasmania within seven weeks offish stocking.
Infauna community conditions (biomass
-------
transferred from one bacterium to another (Aoki et al., 1987a). The presence of plasmids has been
documented in both fish pathogenic bacteria (see above citations) and in native aquatic bacteria (Burton et
al., 1982).
An FDA study to evaluate the use of OTC for aquatic applications analyzed the environmental impact of the
antibiotic on disease control in lobsters held in impoundments Katz (1984). Based on seawater dilution and
lack of long-term selective pressure favoring the persistence of OTC resistant organisms, Katz (1984)
concluded that "there should be no build-up of antibiotic resistant population of microorganisms from the
use of OTC in treating gaffkemia in lobsters." In the same report, Katz concluded that "the potential of R-
factor (resistance-factor) transfer between organisms should be minimal", due to dilution, low levels of
nutrients, low temperatures, and high salinity of seawater.
The technical literature cited above indicates the several factors. They are occurrence of antibiotic resistant
bacteria in association with aquaculture depends on the diversity, frequency, and dosage of antibiotic
administration, and environmental conditions of culture including temperature, dilution of the antibiotics,
and the containment of the fish and associated bacteria.
The reports of antibiotic resistance from Japan are from very intensive aquaculture sites characterized by
warm temperatures, high densities offish grown in confined ponds, and the use of a variety of antibiotics
not registered for use in the United States. As well, the dosage and duration of antibiotic treatment in Japan
appears to exceed both legal and general practices in the United States. Thus, while these studies document
antibiotic resistance in fish pathogenic bacteria due to the administration of antibiotics, they should not be
interpreted to indicate that similar antibiotic resistance will occur under very different environmental
conditions and fish husbandry practices. Importantly, studies (Austin, 1985; Aoki et al., 1984) have noted that
the increased level of antibiotic resistance associated with antibiotic use around fish farms was soon reduced
after antibiotic use stopped. This phenomenon has been observed in human medicine (Forfar et al., 1966)
where dramatic declines in resistance levels of bacteria occur after antibiotic treatments are stopped.
The possibility of transfer of drug-resistance factors from a fish disease-causing bacteria to a potential human
disease-causing bacteria, V. parahaemolyticus, was investigated in Japan (Hayashi et al., 1982). Using test
tube conditions and temperatures of about 86°F to 96°F, these authors were able to transfer drug resistance
to V. parahaemolyticus. These authors also noted that in Japan, where antibiotics have been extensively used
in aquaculture, drug-resistant strains of the V. parahaemolyticus have never been found in the environment.
Toranzo et al (1984) reported the transfer of drug resistance from several bacteria isolated from rainbow
trout to the bacterium, Escherichia coli. The transfer to resistance was performed under laboratory
conditions at 25° C (77° F). The studies demonstrated the potential for transfer under controlled laboratory
conditions and these authors concluded that "Responsible use of drugs in aquaculture will aid in minimizing
the development and spread of R+ factor-carrying microorganisms that may confer drug resistance...".
The accumulation of antibiotic residues in shellfish near fish farms has received little study. In the Puget
Sound area (Tibbs et al., 1988) found that mussels, oysters, and clams suspended within a matrix of net pens
in which coho salmon were being given food supplemented with OTC had no detectable levels of the
antibiotic in their tissues. That study examined the phenomenon of antibiotic accumulation in shellfish under
worst-case conditions with regard to the distance between the fish pen and shellfish (the shellfish were
placed within the matrix offish pens). Weston (1986) noted the large dilution factor that would occur when
antibiotics are used in a net pen. He made conservative calculations and computed a diluted level of 3 parts
per billion of OTC in a parcel of water passed through a fish pen receiving medicated feed. Given this dilution
factor and the water-soluble nature of antibiotics like OTC, Weston (1986) concluded that there was little
potential for bioaccumulation of antibiotics used in fish farming.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 41 of 85
-------
Jacobsen and Bergline (1988) reported the persistence of OTC in sediments from fish farms in Norway. These
authors also conducted laboratory tests and concluded that the half-life (time required for a given
concentration to decay to 50 percent of the starting concentration) for OTC in marine sediments was about
ten weeks, but would likely depend on sediment type and other factors. They examined sediments from
underneath four farms, but did not report the duration or quantities of OTC applied at each location. OTC
was found in sediments from three of the four farms at levels from 0.1 to 4.0 mg/kg (ppm) of dry matter. This
level would potentially be high enough to be inhibitory to marine bacteria (1-2 ppm is considered inhibitory)
including vibrios. However, since the concentration is reported relative to dry weight, it overestimates the
actual concentration in hydrated sediment. The study does demonstrate that measurable OTC can
accumulate below fish farms. Conservatively, the study can be interpreted to show the highest
concentrations were just above inhibitory levels on a dry-weight basis. The authors also noted that the
oxidation state of the sediments would affect the half-life of OTC. An Environmental Assessment of OTC by
the FDA (USFDA, 1983) concluded that "the use of OTC is beneficial to control diseases in aquatic
environment and does not pose adverse effects on this compartment. However, steps should be developed
to avoid the emergence of drug-resistant organisms."
Accumulation of antibiotics in marine sediments is also a function of the dilution factor (which determines
the level of antibiotic reaching the sediment), biotransformation of the compound in the sediment, oxidation
state of the sediment, and water solubility of the antibiotic. Levels of OTC such as those calculated by Weston
(1986) to reach sediments are not likely to have inhibitory effects on non-pathogenic bacteria, which are little
affected at levels below 1 ppm (Carlucci and Pramer, 1960). In their study of the microbial quality of water in
intensive fish rearing, Austin and Allen-Austin (1985) note that while it is difficult to make generalizations,
their study indicated that two freshwater fisheries they monitored did not produce "a major imbalance in
the aquatic bacterial communities."
Although some technical details require further study, the issues surrounding antibiotic use in fish farming
have received some detailed study. Studies demonstrate that antibiotics will be released into the
environment when used as a medication for farmed fish. Antibiotics have not been detected in shellfish held
near salmon net pens. One Norwegian study found concentrations of one antibiotic may have been close to
inhibitory levels in three of four farms. The concentrations of antibiotics outside of the immediate proximity
of the fish pens are regarded by most authors as being too low to have adverse effects.
The presence of plasmids, a mechanism by which bacteria transfer resistance, is documented in pathogenic
and native aquatic bacteria. Antibiotic resistance has been recorded in bacteria around fish farms. Most of
the technical literature describing antibiotic resistance in fish pathogenic bacteria is based on studies of
aquaculture practices and environmental conditions not comparable with salmon net-pen farming in the
Puget Sound region. These conditions include high temperatures, high densities offish, close proximity of
multiple farms, and use of a variety of antibiotics not used in fish farming in the United States. Conditions in
the studies reporting antibiotic resistance favor the development of resistance. In comparison, salmon net-
pen farming in the Puget Sound region would not favor the development of antibiotic resistance. In addition,
the federal regulations that apply to the use of antibiotics in fish farming in the United States appear to be
much more stringent than those that apply in Japan and Europe, where most of the technical literature has
originated. Antibiotic resistance tends to disappear when antibiotic administration is stopped. Shellfish held
within a net-pen complex did not accumulate detectable levels of OTC. This observation and the calculated
dilution of antibiotics away from the fish pens further suggest that any quantities of antibiotics accumulated
in shellfish, or other benthic or planktonic marine invertebrates not near the pens would be substantially
below levels of concern.
The lack of antibiotic resistance in a potential human disease-causing bacteria such as V. parahaemolyticus
in Japan, despite the extensive use of antibiotics in aquaculture there, indicates the transfer of drug
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 42 of 85
-------
resistance from fish to human pathogenic bacteria is unlikely. It appears such transfer is a laboratory
phenomenon, which requires highly controlled conditions and is not representative of phenomena that occur
in the environment. The Toranzo et al (1984) study further demonstrates the potential for drug resistance
transfer under controlled conditions (77°F).
The applicant has indicated that FDA-approved antibiotics or other therapeutants will not likely be used
(within any feed or dosing the rearing water) during the proposed project.19 The need for drugs is minimized
by the strong currents expected at the proposed action area, the low fish culture density, the cage material
being used, and the constant movement of the cage. In the event that drugs are used, the NPDES permit
requires that the use of any medicinal products including therapeutics, antibiotics, drugs, and other
treatments are to be reported to the EPA. The report must include types and amounts of medicinal product
used and the period of time it was used.
9.6 Waste Deposition Analysis
The proposed project generates and discharges various amounts of solid and dissolved wastes depending on
the fish biomass contained and amount of feed added daily. Solid waste consists primarily of unconsumed
feed and fecal material. Other minor sources of solid wastes include dead fish, fish parts (i.e. scales, mucous,
etc.) and material dislodged during net cleaning operations. Dissolved wastes include fish metabolic wastes,
plus therapeutic agents (e.g. antibiotics), if used, antifoulants, if applicable. The focus of this analysis is the
discharge of the primary solid wastes, feed and fecal material and dissolved metabolic wastes.
This facility as proposed consists of a single 17 m diameter floating cage estimated to hold approximately
80,000 lbs of fish at harvest. It is estimated that feeding rates would approximately 745 lbs per day at the
maximum expected fish biomass. Factors influencing the transport and fate of materials discharged from net-
pen facilities include oceanographic characteristics of the receiving water, physical characteristics of the net-
pen, water depth below the net-pen, configuration and orientation of the net-pen system in relation to
predominant currents, type of food used, fish feeding rates and stock size. Oceanographic considerations
include tides, wind, stratification, and current velocities and direction.
The NCCOS conducted environmental modelling analysis of the proposed project to help determine the fate
and effects of solid wastes discharged from the net-pen at maximum production rates. Numerical models
were constructed based upon anticipated farming parameters including configuration (net pen volume and
mooring configuration), fish production (species, biomass, size) and feed input (feed rate, formulation,
protein content). It should be noted that the models used the maximum fish production amounts for the
entirety of the simulation period. Several model scenarios were constructed, the first based on the actual
estimated production of a single cohort to harvest. The second scenario examined the solids discharge based
on a doubling of the estimated actual production to provide a "worst case" for potential impacts. The third
model scenario assumed a maximum biomass for the entire 5-year term of the NPDES permit.
9.6.1 Solid Waste Discharge
A solids deposition model was performed using data from the production model, as well as environmental
and oceanographic data on the proposed offshore location (see NCCOS technical reports in Appendix A and
B). DEPOMOD and NewDEPOMOD, a particle tracking model for predicting the flux of particulate waste
material (with resuspension) and associated benthic impact, was developed for net-pen fish farms. Net
depositional flux of organic carbon was predicted in g m2/yr on a two-dimensional grid overlaid on the farm
footprint. The grid size of 4 km2 was selected such that it would encompass the whole depositional footprint.
19 The applicant is not expected to use any drugs; however, in the unlikely circumstance that therapeutant treatment is needed, three
drugs were provided to the EPA as potential candidates (hydrogen peroxide, oxytetracycline dihydrate, and florfenicol).
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 43 of 85
-------
The results of the first depositional model show that for the estimated production values, net organic carbon
accumulation would be at 3.0 g/m2/yr or less for 99.7 percent of the test grid. The second depositional model
performed at twice the estimated production, net organic carbon accumulation would be 5.0 g/m2/yr or less
for 99.0 percent of the grid.
The model also estimated a biotic index, Infaunal Tropic Index (ITI), that is used as an indicator of organic
enrichment based on expected changes in benthic macroinvertebrate community feeding responses to
increases in deposited organic matter. The three model simulations resulted in ITI predictions ranging from
58.67 to 58.96. The predicted ITI close to 60 suggests that the proposed Velella project will not likely have a
discernable impact on the benthic infaunal community around the site. The third modeling scenario (full
production for the 5-year term) showed that "Velella project will present challenges for monitoring and
detecting environmental impacts on sediment chemistry or benthic communities because of the circulation
around the project location and the small mass flows of materials from the net pen installation."
9.6.2 Dissolved Wastes
The NCCOS technical reports estimated that 2,743 kg of ammonia nitrogen would be produced using the
maximum biomass for the entire 280-day fish production cycle. The report suggested that daily ammonia
production at levels twice as high as estimated will be undetectable within 30 meters of the cage at typical
current flows regimes in the vicinity of the proposed site.
The NCCOS technical report did not provide dilution estimates for the dissolved waste discharge downstream
of the cage. Modelling input parameters within the NCCOS report were used to calculate the flow-averaged
ammonia concentration at the downstream edge of the cage for comparison with published water quality
criteria for ammonia in saltwater (EPA, 1989). The ambient water quality criteria for ammonia in saltwater
state that "saltwater aquatic organisms should not be affected unacceptably if the four-day average
concentration of un-ionized ammonia does not exceed 0.035 mg/l more than once every three years on the
average and if the one-hour average concentration does not exceed 0.233 mg/L more than once every three
years on the average."
A total ammonia loading of 2,743 kg, based an initial estimated 280-day fish production cycle (Table 3 within
the NCCOS technical report) was averaged to 9.8 kg/ammonia/day and 113.0 milligrams per second (mg/s).
The flow-averaged ammonia concentration is estimated at 0.0072 mg/l (based on an ammonia production of
9.8 kg/day loading rate).20
Since the NCCOS technical report, changes in estimated production parameters resulted in total ammonia
loading estimates for a 365-day production cycle of 3,978 kg/day. The average daily ammonia load was
calculated at 10.9 kg/d and 126.0 mg/s. The flow-averaged ammonia concentration was estimated at 0.008
mg/l (based on an ammonia production of 10.9 kg/day loading rate). Estimates of the flow-averaged
ammonia concentrations at the cage edge at maximum fish production are significantly below the published
ammonia aquatic life criteria values for saltwater organisms.
20 The current velocity used for flow calculations is 13.26 cm/s, which is the total mean from Table 4 within the NCCOS technical report. A
lateral two-dimensional cage surface area is 1,190,000 cm2. The lateral flow through the cage was estimated 15,779,400 cm3/s.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 44 of 85
-------
10.0 Evaluation of the Ocean Discharge Criteria
This section summarizes EPA's review of the ten factors that the EPA must consider in determining, pursuant
to 40 CFR § 125.122(a), whether a discharge will cause unreasonable degradation of the marine environment,
to ensure that the proposed NPDES permit complies with CWA § 403. This section discusses how conditions
and limitations included in the final permit for the proposed project ensure compliance with these ODC, and
the determination, under CWA § 403, that the NPDES permit will not cause unreasonable degradation of the
marine environment with all NPDES permit limitations, conditions, and monitoring requirements in effect.
10.1 Evaluation of the Ten ODC Factors
10.1.1 Factor 1 - Quantities, Composition, and Potential for Bioaccumulation or Persistence of Pollutants
The quantities and composition of the discharged material were presented in Section 4 and the potential for
bioaccumulation or persistence was addressed in Section 9. Due to the relatively small fish biomass
production estimated for this demonstration project and limited discharges other than fish food and fecal
matter, the volume and constituents of the discharged material are not considered sufficient to pose a
significant environmental threat through bioaccumulation or persistence. However, to confirm the EPA's
decision and as a precaution against any changes in operational practices that could change the EPA's
assumptions, the NPDES Permit requires environmental monitoring and implementation of an environmental
monitoring plan to meet the requirements of the CWA § 402 and CWA § 403.
10.1.2 Factor 2 - Potential for Biological, Physical, or Chemical Transport
Section 3 and 4 of this document discusses the oceanographic process characteristic of the continental shelf
off the west coast of Florida responsible for the physical transport offish wastes in the environment. Section
8 discusses the results of predicted impacts to the water column and waste deposition on the seafloor
surrounding the proposed facility.
Due to the small scale of the proposed project and because the discharged wastes are largely comprised of
organic and inorganic particulates and dissolved metabolic wastes, there is little potential for biological or
chemical transport. Ocean currents are expected to flush the cages sufficiently to carry wastes away from
cages and dilute and disperse dissolved and solid wastes over a large area. For any solid matter settling on
the seafloor, bioturbation should serve to mix sediments vertically at low to moderate benthic loading rates
and resuspension of sediments should further enhance the dispersion of uneaten food and fecal matter. High
loading rates that would be expected to impair benthic communities and reduce the effect of bioturbation
are not expected to occur. The physical transport of these waste streams is considered to be the most
significant source for dispersion of the wastes and monitoring and regulation is based on the results of those
investigations.
10.1.3 Factor 3 - Composition and Vulnerability of Biological Communities
The third factor used to determine no unreasonable degradation of the marine environment is an assessment
of the presence of unique species or communities of species, endangered species, or species critical to the
structure or function of the ecosystem. Section 4 describes the biological communities of the eastern Gulf
including the presence of endangered species and Section 8 discusses the factors that make these
communities or species vulnerable to the permitted activities.
High organic loading from fish farms have been shown to alter the physical structure of benthic sediment
and to cause anoxic conditions which reduce diversity and abundance of infauna, meiofauna and epibenthic
organisms. The area around the proposed facility is mainly comprised of soft sand sediments and their
characteristic benthic communities. Results from deposition modeling (Section 8) show the potential for
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 45 of 85
-------
benthic impacts over an area in excess of 1 km2. The potential for impacts due to toxic effects from a
demonstration size fish farm discharge, however, is minimal.
10.1.4 Factor 4 - Importance of the Receiving Water to the Surrounding Biological Community
The importance of the receiving waters to the species and communities of the eastern Gulf is discussed in
Section 4 and Section 5 in conjunction with the discussion of the species and biological communities. The
receiving water is considered when determining the discharge rate restrictions. The dissolved nutrient
estimates and deposition modeling considered concentrations of organic particulates that may have impacts
on aquatic life. Permit limitations on minor discharges ensure that levels of these effluents are below levels
that could have impacts on local biological communities. EPA finds that operating discharges from the
proposed facility will have little adverse impacts on species migrating to coastal or inland waters for spawning
or breeding.
10.1.5 Factor 5 - Existence of Special Aquatic Sites
The existence of special aquatic sites and proximity to the proposed project are discussed in Section 7. EPA
has determined that the proposed area is located sufficiently far from special aquatic sites off the west Florida
coast that any impacts resulting from the proposed facility will likely be limited to the surrounding area,
within 300-500 meters from the perimeter of the cage array, and will therefore not impact any special aquatic
sites.
10.1.6 Factor 6 - Potential Impacts on Human Health
Section 9 details the Federal and state human health criteria and standards for pollutants of concern. These
criteria and standards are for marine waters based on fish consumption. These analyses compare projected
pollutant concentrations with these criteria and standards, and indicate that there will be an insignificant
depositional and water quality impact. In addition, the permit prohibits the discharge or use of antifouling
agents or chemical fish treatments other than antibiotics allowed by the FDA animals raised for human
consumption. Based on consideration of this factor, EPA finds that the proposed facility is not likely to have
impacts on human health.
10.1.7 Factor 7 - Recreational or Commercial Fisheries
The commercial and recreational fisheries occurring in the eastern Gulf, mainly Alabama, Florida, and
Mississippi, are assessed in Section 6. Based on the following, EPA finds that the discharges from the project
will not adversely affect water quality or the health of these fisheries:
1. The modeling performed for the proposed project found that there would be minimal to insignificant
impact on water quality and seafloor benthic communities.
2. EPA determined that the conditions and limitations in the permit for the proposed project are
adequate to ensure that the recreational and commercial fisheries will not be adversely impacted. In
addition to environmental monitoring, the NPDES permit will include a requirement that all fish
stocked must obtain an Official Certificate of Veterinary Inspection prior to being stocked, and
implement BMPs related to fish health management.
3. EPA evaluated that potential social, economic, and environmental impacts to commercial and
recreational fisheries caused by the proposed project within the Environmental Assessment to
comply with the National Environmental Policy Act (NEPA).
4. The EPA determined, in consultation with NMFS, that there the minimal short-term impacts
associated with the discharge will not result in substantial adverse effects on Essential Fish Habitat
(EFH), habitats of particular concern, or managed species in any life history stage, either immediate
or cumulative, in the proposed project area (see EFH consultation record for more information).
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 46 of 85
-------
10.1.8 Factor 8 - Coastal Zone Management Plans
Section 7 provides an evaluation of the coastal zone management plan for the State of Florida. On January 3,
2019, the permit applicant submitted a CZMA consistency determination to the Florida State Clearinghouse
with the Florida Department of Environmental Protection. On January 15, 2019, the Florida Department of
Agriculture and Consumer Services (FDACS) documented that the coastal consistency determination
submitted by the applicant was consistent with all FDACS statutory responsibilities for aquaculture. On
February 18, 2019, the Florida Fish and Wildlife Conservation Commission (FWC) found that the applicant's
coastal consistency determination was consistent with FCMP. Therefore, the EPA has determined that the
action covered by this permit is consistent with the CZMA and its implementing regulations.
10.1.9 Factor 9 - Other Factors Relating to Effects of the Discharge
Effluent Guidelines and Standards have been developed for the Concentrated Aquatic Animal Production
(CAAP) Point Source Category for facilities producing 100,000 pounds or more of aquatic animals per year in
floating net pens or submerged cage systems (40 CFR Part 451 Subpart B). The New Source Performance
Standards effluent limitation guidelines for the CAAP industry were applied to the proposed project in the
NPDES permit. The effluent limitations and standards for these facilities are non-numeric effluent limitations
expressed as practices designed to control the discharge of pollutants from these types of operations, the
NPDES permit will include effluent limitations expressed as best management practices (BMPs) for feed
managment, waste collection and disposal, harvest discharge, carcass removal, materials storage,
maintenance, record keeping, and training. Therefore, impacts to water quality will be reduced by a range of
non-numeric effluent limitations through the implementation of project-specific BMPs and operational
measures.
Factor 9 of the marine unreasonable degredation criteria are "such other factors relation to the effects of
the discharge as may appropriate. Factor 9 was considered, along with the other 9 factors, in developing
permit conditions to ensure that unreasonable degradation to the marine environment will not occur as a
result of the discharges from the proposed facility. As provided in 40 CFR § 125.123(a),21 the EPA has included
permit conditions that have been determined to be necessary to ensure that unreasonable degradation of
the marine environment will not occur by including necessary conditions specified in 40 CFR § 125.123(d),
including the following conditions:
1. Implementation of environmental monitoring and an environmental monitoring plan will be required
in the NPDES permit to meet the requirements 40 CFR § 125.123(d)(2).22 The applicant will be
required to monitor and sample certain water quality, sediment, and benthic parameters at a
background (up-current) location and near the cage.
2. In accordance with 40 CFR § 125.123(d)(3),23 the NPDES permit must include two conditions related
to fish health management and the indirect discharge of pathogens:
a. a requirement that all stocking of live aquatic organisms, regardless of life stage, must be
accompanied by an Official Certificate of Veterinary Inspection signed by a licensed and
accredited veterinarian attesting to the health of the organisms to be stocked; and
b. the BMP plan shall include conditions to control or minimize the transfer of pathogens to wild
21 40 CFR § 125.123(a) states that "If the director on the basis of available information including that supplied by the applicant pursuant to
§ 125.124 determines prior to permit issuance that the discharge will not cause unreasonable degradation of the marine environment after
application of any necessary conditions specified in §125.123(d), he may issue an NPDES permit containing such conditions."
22 40 CFR § 125.123(d)(2) states that EPA is allowed to "specify a monitoring program, which is sufficient to assess the impact of the
discharge on water, sediment, and biological quality including, where appropriate, analysis of the bioaccumulative and/or persistent impact
on aquatic life of the discharge."
23 40 CFR § 125.123(d)(3): "Contain any other conditions, such as performance of liquid or suspended particulate phase bioaccumulation
tests, seasonal restrictions on discharge, process modifications, dispersion of pollutants, or schedule of compliance for existing discharges,
which are determined to be necessary because of local environmental conditions, and"
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 47 of 85
-------
fish.
3. In accordance with CWA § 403 of the, 40 CFR § 125.123(a), and 125.123(d)(3), the NPDES permit will
contain a condition that "The discharge from the facility shall not cause unreasonable degradation of
the marine environment underneath the facility and in the surrounding area" under 40 CFR §
125.123(d)(3).
10.1.10 Factor 10 - Marine Water Quality Criteria
The Federal and state marine water quality criteria and standards are discussed in Section 8. The proposed
facility will be located in federal waters where no federal or state criteria apply; however, the discharges
from the proposed project are not expected to exceed the recommended federal water quality criteria for
marine waters that were considered in this ODC Evaluation.
10.2 Conclusion
The consideration of the ten factors discussed in this ODC Evaluation were based on the available information
from published literature regarding impacts that have occurred near net pen fish farms from around the
world, and information in the Administrative Record for the NPDES permit action regarding the proposed
facility and the potential impacts of discharges from the proposed facility. Sufficient information currently
exists regarding open water marine fish farming activities and expected impacts from such activities, coupled
with information regarding the proposed discharge, to allow the EPA to adequately predict likely
environmental outcomes for the Proposed project.
The EPA also determined that the NPDES permit must contain necessary conditions allowed by 40 CFR §
125.123(d). First, the NPDES permit will contain a comprehensive environmental monitoring plan that will
confirm EPA's determination and ensure no significant environmental impacts will occur from the proposed
project. Second, the NPDES permit must include a requirement that all stocking of live aquatic organisms,
must obtain an Official Certificate of Veterinary Inspection prior to being stocked, and implement BMPs
related to fish health management. Finally, the NPDES permit will contain a condition that the discharge from
the facility shall not cause unreasonable degradation of the marine environment. EPA finds that these
conditions, along with other the other conditions in the NPDES permit (i.e. BMP plan, Facility Damage
Prevention and Control Plan, etc.), will ensure thatthe discharges from the facility do not cause unreasonable
degradation of the marine environment.
The EPA finds that "no-unreasonable degradation" will likely occur as a result of the discharges from this
project based on the available scientific information concerning open ocean fish farming, the results
predicted by deposition and dilution modeling, the effluent limit guidelines for the CAAP industry that are
being applied to this facility, and the conditions included within the NPDES permit as allowed by the ODC
implementing regulations.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 48 of 85
-------
References
Ackefors, H. and A. Sodergren. 1985. Swedish experiences of the impact of aquaculture on the environment.
International Council for the Exploration of the Sea C. M. 1985/E: 40. 7pp.
Akashi, A. and T. Aoki. 1986. Characterization of transferable R plasmids from Aeromonas hydrophilia.
Bulletin of the Japanese Society of Scientific Fisheries 52(4):649-655.
Aoki, T. 1975. Effects of chemotherapeutics on bacterial ecology in the water of ponds and the intestinal
tracts of cultured fish, au (Plecoglossus altivelis) 19(1):7-12.
Aoki, T. 1988. Drug-resistant plasmids from fish pathogens. Microbiological Sciences 5(7)219-223.
Aoki, T. and A. Takahashi. 1986. Tetracycline-resistant gene of a non-transferable R plasmid from fish-
pathogenic bacteria Aeromonas salmonicida. Bulletin of the Japanese Society of Scientific Fisheries
52(11):1913-1917.
Aoki, T. and A. Takahashi. 1987. Class D tetracycline resistance determinants of R plasmids from the fish
pathogens Aeromonas hydrophila, Edwardsiella tarda, and Pasteurella piscicida. Antimicrobial Agents and
Chemotherapy 31(8)1278-1280.
Aoki, T. and T. Kitao. 1985. Detection of transferable R plasmids in strains of the fish pathogenic bacterium,
Pasteurella piscicida. Journal of Fish Diseases 8:345-350.
Aoki, T., A. Akashi and T. Sakaguchi. 1986. Phylogenetic relationships of transferable R plasmids from
Edwardsiella tarda. Bulletin of the Japanese Society of Scientific Fisheries 52(7):1173-1179.
Aoki, T., S. Egusa and T. Arai. 1974. Detection of R factors in naturally occurring Vibrio anguillarum strains.
Antimicrobial Agents and Chemotherapy 6(5):534-538.
Aoki, T., S. Egusa, C. Yaka and T. Watanabe. 1972. Studies of drug resistance and R factors in bacteria from
pond-cultured salmonids. I. Amago (Oncorhynchus rhodurus macrostomus) and Yamame (Oncorhynchus
masou ishikawae). Japanese Journal of Microbiology 16(3):233-238.
Aoki, T., S. Egusa, T. Kimura and T. Watanabe. 1971. Detection of R factors in naturally occurring Aeromonas
salmonicida strains. Applied Microbiology 22(4):716-717.
Aoki, T., T. Arai and S. Egusa. 1977. Detection of R plasmids in naturally occurring fish-pathogenic bacteria,
Edwardsiella tarda. Microbiology and Immunology 21(2)77-83.
Aoki, T., T. Kanazawa and T. Kitao. 1985. Epidemiological surveillance of drug resistance Vibrio anguillarum
strains. Fish Pathology 20(2/3):190-208.
Aoki, T., T. Kitao and K. Kawano. 1981. Changes in drug resistance of Vibrio anguillarum in cultured ayu,
Plecoglossus altivelis Temminck and Schlegel, in Japan. Journal of Fish Diseases 4:223-230.
Aoki, T., T. Kitao, S. Watanabe and S. Takeshita. 1984. Drug resistance and R plasmids in Vibrio anguillarium
isolated in cultured ayu (Plecoglossus altivelis). Microbiology and Immunology 28(l):l-9.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 49 of 85
-------
Aoki, T., T. Sakaguchi and T. Kitao. 1987. Multiple drug-resistant plasmids from Edwardsiella tarda in eel
culture ponds. Nippon Suisan Gakkaishi 53(10):1821-1825.
Aoki, T., T. Satoh and T. Kitao. 1987. New tetracycline resistance determinant on R plasmids from Vibrio
anguillarum. Antimicrobial Agents and Chemotherapy 31(9)1446-1449.
Aoki, T., Y. Mitoma and J.H. Crosa. 1986. The characterization of a conjugative Rplasmid isolated from
Aeromonas salmonicida. Plasmid 16:213-218.
Aure, J. and A. Stigebrandt, 1990. Quantitative estimates of eutrophication effects of fish farming on fiords.
Aquaculture, 90 (1990) 135-136.
Austin, B. 1985. Antibiotic pollution from fish farms: effects on aquatic microflora. Microbiological Sciences.
2(4):113-117.
Austin, B. and D. Allen-Austin. 1985. Microbial quality of water in intensive fish rearing. Journal of Applied
Bacteriology. 59(Suppl.l4):207S-226S.
Austin, H. 1970. Florida Middle Ground. Int. Poll. Bull. 2(2):71-72.
BOEM. 2013. Gulf OCS Oil and Gas Lease Sales: 2014 and 2016 Eastern Planning Area Lease Sales 225 and
226 Final Environmental Impact Statement. Volume 1: Chapters 1-8 and Keyword Index; Volume 2: Figures,
Tables and Appendices. BOEM Gulf OCS Region. October 2013. BOEM 2013-200.
BOEM. 2012. Outer Continental Shelf Oil and Gas Leasing Program: 2012-2017. Final Programmatic
Environmental Impact Statement. USDOI. BOEM 2012-030.
Brown, J.R., R.J. Gowen, and D.S. McLusky. 1987. The effect of salmon farming on the benthos of a Scottish
sea loch. Journal of Experimental Marine Biology. 109: 39-51.
Bullock, G.L., I.M. Stuckey, D. Collis, R.L. Herman and G. Maestrone. 1974. In vitro and in vivo efficacy of a
potentiated sulfonamide in control of furunculosis in salmonids. Journal of the Fisheries Research Board of
Canada. 31:75-82.
Burton, N.F., M.J. Day and A.T. Bull. 1982. Distribution of bacterial plasmids in clean and polluted sites in a
south Wales river. Applied and Environmental Microbiology. 44:1026-1029.
Butz, F. and B. Vens-Cappell. 1982. Organic load from the metabolite products of rainbow trout fed with dry
food. In J.S. Alabaster (ed.), Report of the EIFAC Workshop on Fish-Farm Effluents. Silkeborg, Denmark, 26-
28 May 1981, pp 7382. EIFAC Tech. Rep. 41.
Carlucci, A.F. and D.Pramer. 1960. An evaluation of factors affecting the survival of Escherichia cold in sea
water. Applied Microbiology. 8(4):251-254.
Cho, C.Y. and Bureau, D.P. (2001). A review of diet formulation strategies and feeding systems to reduce
excretory and feed wastes in aquaculture. Aquaculture Research 32 (Suppl. 1),
349-360.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 50 of 85
-------
Clark, E.R., J.P. Harman and J.R.M. Forster. 1985. Production of metabolic products by intensively farmed
rainbow trout, Salmo gairdneri Richardson. Journal of Fisheries Biology. 27:381-393.
Corcoran, A., Dornback, M., Kirkpatrick, B., and Jochens, A. 2013. A primer on Gulf Harmful Algal Blooms. Gulf
Coastal Ocean Observing System. Texas A&M University, pp.11.
Craig, S., 2009. Understanding fish nutrition, feeds and feeding. Virginia Polytechnic Institute and State
University. Department of Fisheries and Wildlife Sciences. Virginia Cooperative Extension Pub. 420-256.4 pp.
Cross, S.F. 1988. A preliminary study of the deposition and dispersion characteristics of waste materials
associated with salmon farming operations in British Columbia. Report to B.C. Min. Environment and Parks.
Aquametrix Research Ltd. Sidney, B.C.
Dagg, M.J., and Breed, G.A. 2003. Biological effects of Mississippi River nitrogen on the northern Gulf—a
review and synthesis. Journal of Marine Systems 43: 133-152
Dixon, I. 1986. Fish Farm Surveys in Shetland; August 1986. Summary of survey reports, Volume 1. A Report
to NCC, Shetland Island Council and Shetland Salmon Farmers Assoc. Oil Pollution Research Unit, Field Studies
Council, FSC/OPRU/30/86. Orielton Field Center, Pembroke, Dyfed Scotland.
Earll, R.C., G. James, C. Lamb, and R. Pagett. 1984. A report on the effects of fish farming on the marine
environment of the Western Isles. Marine Biological Consultants Ltd./Nature Conservancy Council. 45 pp.
Edwards, D.J. 1978. Salmon and Trout Farming in Norway. Fishing News Books, Ltd. Farnham, UK.
El-Sayed, S.Z. 1972. Primary productivity and standing crop of phytoplankton in the Gulf. In: El-Sayed, S.Z. et
a I., eds. Chemistry, primary productivity and benthic algae of the Gulf. Serial atlas of the marine environ.,
Folio 22. New York, NY: American Geographic Society, pp. 8-13.
FAO Fisheries and Aquaculture Program, (n.d.) Cultured Aquatic Species Information Program. Salmo salar
(linnacus, 1758). 9 pp.
Flint, R.W. and D. Kamykowski. 1984. Benthic nutrient regeneration in South Texas coastal water. Estuar.
Coast. Shelf. Sci. 18(2):221-230.
Flint, R.W. and N.N. Rabalais. 1981. Environmental Studies of a Marine Ecosystem: South Texas Outer
Continental Shelf. Univ. Texas Press, Austin. 272 pp.
Forfar, J.O., A.J. Keay, A.F. Macabe, J.C. Gould and A.D. Bain. 1966. Liberal use of antibiotics and its effect in
neonatal staphylococcal infection, with particular reference to erythromycin. Lancet.ll:295-300.
Froehlich HE, Smith A, Gentry RR and Halpern BS. 2017. Offshore Aquaculture: I Know It When I See It. Front.
Mar. Sci. 4:154. doi: 10.3389/fmars.2017.00154
Giles, H. 2008. Using Bayesian networks to examine consistent trends in fish farm benthic impact studies.
Aquaculture 274: 181-195.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 51 of 85
-------
Gowen, R. J. and N.B. Bradbury 1987. The ecological impact of salmonid farming in coastal waters.
Oceanographic Marine Biology Annual Review. 25:563-575
Gowen, R., J. Brown, N. Bradbury, and D.S. McLusky. 1988. Investigations into benthic enrichment,
hypernutrification and eutrophication associated with mariculture in Scottish coastal waters (1984 - 1988).
Prepared for the Highlands and Islands Development Board, Crown Estates Commission, Nature Conservancy
Council, Countryside Commission for Scotland, and Scottish Salmon Growers Association. 289 pp.
Hall, P. and O. Holby. 1986. Environmental Impact of a Marine Fish Cage Culture. ICES. C.M. 1986/F:46. 14 p.
Hargrave, B. T., Duplisea, D. E., Pfeiffer, E. and Wildish, D. J. (1993) Seasonal changes in benthic fluxes of
dissolved oxygen and ammonium associated with manned cultured Atlantic salmon. Marine Ecology Progress
Series 96, 249-257.
Harris, G.P. 1986. Phytoplankton Ecology, Structure, Function and Fluctuation. Chapman and Hall. London.
Hasan, M.R. 2012. Transition from low-value fish to compound feeds in marine cage farming in Asia. FAO
Fisheries and Aquaculture Technical Paper. No. 573. Rome, FAO. 198 pp.
Hasan, M.R. & Soto, S. 2017. Improving feed conversion ratio and its impact on reducing greenhouse gas
emissions in aquaculture. FAO Non-Serial Publication. Rome, FAO. 33 pp.
Hayashi, F., K. Hardada, S. Mitsuhashi and M. Inoue. 1982. Conjunction of drugresistance plasmidsfrom Vibrio
anguillarum to Vibrio parahaemolvticus. Microbiology and Immunology 26(6):479-485.
Hayes, S. A., E. Josephson, K. Maze-Foley, and P. E. Rosel (Editors). 2017. U.S. Atlantic and Gulf Of Mexico
marine mammal stock assessments 2016. NOAA Technical Memorandum NMFS-NE-241. 282 pp.
Hochachaka, P.W. 1969. Intermediary metabolism in fishes, pp. 351-389 In W.S. Hoar and D.J. Randall (Eds.),
Fish Physiology. Vol. 1. Academic Press, New York.
Holmer, M. 2010. Environmental issues of fish farming in offshore waters: perspectives, concerns and
research needs. Aquacult Environ Interact. Vol. 1: 57-70.
Holmer, M. (1991) Impacts of aquaculture on surrounding sediments: generation of organic-rich sediments.
In Aquaculture and the Environment, ed. N. Pauw and J. Joyc, vol. 16, pp. 155-175. Aquaculture Society
Special Publication.
Hoese, H.D. and Moore, R.H. 1977. Fishes of the Gulf, Texas, Louisiana, and Adjacent Waters. W.L. Moody,
Jr. Natural History Series; No.l. Texas A&M University press. College Station, TX.
Houde, E.D. and N. Chitty. 1976. Seasonal Abundance and Distribution of Zooplankton, Fish Eggs, and Fish
Larvae in the Eastern Gulf, 1972-1974. Prepared for NMFS, Seattle, WA. NMFS SSRF-701. 18 pp.
Institute of Aquaculture. 1988. The reduction of the impact of fish farming on the natural marine
environment. Report prepared by the Institute of Aquaculture, University of Stirling, Scotland. Prepared for
the Nature Conservancy Council, Scotland. January, 1988.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 52 of 85
-------
Islam, M. 2005. Nitrogen and phosphorus budget in coastal and marine cage aquaculture and impacts of
effluent loading on ecosystem: review and analysis towards model development. Marine Pollution Bulletin
50:48-61.
Iverson, R.L. and T.L. Hopkins. 1981. A summary of knowledge of plankton production in the Gulf: Recent
Phytoplankton and Zooplankton research. Proceedings of a Symposium on Environmental Research Needs in
the Gulf (GulfEX), Key Biscayne, FL, 30 September - 5 October, 1979.
Jacobsen, P. and L. Bergline. 1988. Persistence of oxytetracycline in sediments from fish feces. Aquaculture
70:365-370.
Kalantzi, I., and Karakassis, I. 2006. Benthic impacts of fish farming: Meta-analysis of community and
geochemical data a Marine Pollution Bulletin 52 (2006) 484-493
Karakassis I, Tsapakis M, Hatziyanni E, Papadopoulou KN, and Plaiti W. 2000. Impact of cage
farming offish on the seabed in three Mediterranean coastal areas. ICES
J Mar Sci 57:1462-1471
Karakassis I, Tsapakis M, Smith G, and Rumohr H. 2002. Fish farming impacts in the Mediterranean studied
through sediment profiling imagery. Mar Ecol Prog Ser 227: 125-133
Katz, S.E. 1984. Environmental impact assessment for the use of oxytetracycline to control gaffkemia
infections in lobsters. Report available through Dockets Management Branch, HFA - 305, U. S. Administration,
Room 4625600, Fishers Lane, Rockville, MD 20857.
Kennish, M.J. (ed.). 1989. Practical Handbook of Marine Science. CRC Press Inc. Boca Raton, FL.
Lampadariou, N., Karakassis, I., and Pearson, T.H., 2005. Cost/benefit analysis of a benthic monitoring
programme of organic benthic erichment using different sampling and analysis methods. Marine Pollution
Bulletin 50,1606-1618.
Leipper, D.F., 1970. A sequence of current patterns in the Gulf. Jour. Geo. Res. 75(3): 637-657.
Liao, P. and R. Mayo. 1974. Intensified fish culture combining water reconditioning with pollution abatement.
Aquaculture 3:16-85.
Mangion, M., Borg, J.A., Thompson, R., and Schembri, P.J. 2014. Influence of tuna penning activities on soft
bottom macrobenthic assemblages. Marine Pollution Bulletin 79:164-174.
Maul, G.A., 1977. The annual cycle of the Gulf Loop Current, Part 1: Observations during a one-year time
series. Jour. Mar. Res. 35(l):29-47.
Mazzola, A., S. Mirto, and R. Danovaro. 1999. Initial fish-farm impact on meiofaunal assemblages in coastal
sediments of the western Mediterranean. Mar. Poll. Bull. 38, 1126-1133.
Milner-Rensel Associates. 1986. Aquatic conditions at the Seafarm of Norway net-pen site in Port Angeles
Harbor in April, 1986. Prepared for Sea Farm of Norway, Inc. and the City of Port Angeles Planning
Department. 25 pp. and appendices.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 53 of 85
-------
Mitoma, Y., T. Aoki and J.H. Crosa. 1984. Phylogenetic relationships among Vibrio anguillarum Plasmids.
Plasmids 12:143-148.
MMS. 1983. Final regional environmental impact statement. Proposed OCS oil and gas lease sales 72, 74, and
79 (Central, Western, and Eastern Gulf). Vol. 1, PB84-102805. U.S. Department of the Interior, Washington,
DC. xxxv + 527 pp.
MMS. 1990. Draft environmental impact statement. Gulf Sales 131, 135, and 137: Central Western and
Eastern Planning Areas. Gulf OCS Region Office. MMS 90-0003.
NMFS. 2014. Fisheries Economics of the United States, 2012. U.S. Dept. Commerce, NOAA. Tech. Memo.
NMFS-F/SPO-137, 175p. Available at: https://www.st.nmfs.noaa.gov/st5/publication/index.html.
NMFS. 2014. Fisheries of the United States, 2013. U.S. Department of Commerce, NOAA Current Fishery
Statistics No.2013. Available at: https://www.st.nmfs.noaa.gov/commercial-fisheries/fus/fusl3/index
NMFS. 2015. Fisheries of the United States, 2014. U.S. Department of Commerce, NOAA Current Fishery
Statistics No.2014. Available at: https://www.st.nmfs.noaa.gov/commercial-fisheries/fus/fusl4/index
NMFS. 1983. Water quality surveyed in Clam Bay. Quarterly report (January-March, 1983) by Northwest
Alaska Fisheries Center, National Marine Fisheries Service, National Oceanic Atmospheric Administration,
Seattle, WA.Novotny, A.J. 1978. Vibriosis and furunculosis in marine cultured salmon in Puget Sound. Marine
Fisheries Review. 40(3):52-55.
NOAA. 1975. Environmental Studies of the South Texas Outer Continental Shelf, 1975. Report to the BLM,
I .A. #08550-IA5-19. Volume I.
NOAA. 1986. Proposed Secretarial Fish. Mgmt. Plan, Regulatory Impact Review, Initial Regulatory Flexibility
Analysis and Draft EIS for the Red Drum Fishery of the Gulf.
NOAA. 1991. NOAA Technical Report NMFS 98: Marine Mammal Strandings in the United States.
NOAA. 2009. Final Programmatic Environmental Impact Statement. Fishery Management Plan for Regulating
Offshore Marine Aquaculture in the Gulf. NOAA. National Marine Fisheries Service. 449 pp.
NorSi, G., R.N. Glud, E. Gaard, and K. Simonse. 2011. Environmental impacts of coastal fish farming: Carbon
and nitrogen budgets for trout farming in Kaldbaksfj0r3ur (Faroe Islands). Marine Ecology Progress Series
431:223-241.
Odum, E.P. 1971. Fundamentals of Ecology, 3rd Edition. W.B. Saunders, Philadelphia, PA. In: Kennish, M.J.
(ed.). 1989. Practical Handbook of Marine Science. CRC Press Inc. Boca Raton, FL. 710 pp.
Ortner, P.B., R.L. Ferguson, S.R. Piotrowicz, L. Chesal, G. Berberian, and A.V. Palumbo. 1984. Biological
consequences of hydrographic and atmospheric advection within the Gulf Loop Intrusion. Deep-Sea
Research. Vol. 31, no. 94:1101-1120.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 54 of 85
-------
Pamatmat, M.M., R.S. Jones, H. Sanborn, and A. Bhaqwat. 1973. Oxidation of organic matter in sediments.
EPA-660/3-73-005. U.S. Env. Prot. Agency, Washington, D.C.
Pearson, T.H. and R. Rosenberg. 1978. Macrobenthic succession in relation to organic enrichment and
pollution of the marine environment. Annual Reviews of Oceanography and Marine Biology. 16:229-311.
Pease, B.C. 1977. The effect of organic enrichment from a salmon mariculture facility on the water quality
and benthic community of Henderson Inlet, Washington. Ph. D. Dissertation. University of Washington.
Seattle, Washington.
Penczak, T., W. Galicka, M. Molinski, E. Kusto, and M. Zalewski. 1982. The enrichment of a mesotrophic lake
by carbon, phosphorus and nitrogen from the cage aquaculture of rainbow trout, Salmo gairdneri. Journal of
Applied Ecology. 19:371-393.
Price, C.S. and J.A. Morris, Jr. 2013. Marine Cage Culture and the Environment: Twenty-first Century Science
Informing a Sustainable Industry. NOAA Technical Memorandum NOS NCCOS 164. 158 pp.
Rabalais, N.N. 1986. Oxygen-depleted waters on the Louisiana continental shelf. Proceedings of the MMS,
Information Transfer Meeting, November 4-6, 1986. 4 pp.
Rabalais, N.N., M.J. Dagg, and D.F. Boesch. 1985. Nationwide Review of Oxygen Depletion and Eutrophication
in Estuarine and Coastal Waters: Gulf (Alabama, Mississippi, Louisiana and Texas). Report to NOAA, Ocean
Assessments Division. 60 pp.
Renaud, M.L. 1985. Hypoxia in Louisiana coastal waters during 1983: Implications for fisheries. Fishery
Bulletin 84(l):19-26.
Rensel, J. 1988b. Environmental sampling at the American Aqua Foods net-pen site near Lone Tree Point in
north Skagit Bay. Prepared by Rensel Associates, Seattle, for Pacific Aqua Foods, Vancouver, B.C. and the
Washington Department of Natural Resources. 7 pp. and appendicies.
Rensel, J. 1988c. Phytoplankton and nutrient studies at Squaxin Island net-pens. Technical report prepared
for Parametrix Inc. and The Washington Department of Fisheries. Technical Appendix to the Programmatic
Environmental Impact Statement: Salmon Aquaculture in Puget Sound.
Riley, K., Morris, J. and King, B. 2018. Environmental modelling to support NPDES permitting for Vellela
Epsilon offshore demonstration project in the southeastern Gulf of Mexico. CASS Technical Report.
NOAA/NCCOS/Coastal Aquaculture Siting and Sustainability. 10pp.
Ritz, D. A., Lewis, M. E. and Ma Shen (1989) Response to organic enrichment of infaunal macrobenthic
communities under salmonid seacages. Marine Biology 103, 211-214.
Ryther, J.H. and W.M. Dunstan. 1971. Nitrogen, phosphorus and eutrophication in the coastal marine
environment. Science. (New York) 171:1008-1013.
Sara, G., Scilipoti, D., Mazzola, A., and Modica, A., 2004. Effects of fish farming waste to sedimentary and
particulate organic matter in a southern Mediterranean area (Gulf of Castellammare, Sicily): a multiple stable
isotope study (dl3 and dl5N). Aquaculture 234, 199-213.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 55 of 85
-------
Saunders, R.P., and D.A. Glenn. 1969. Diatoms. Mem. Hourglass Cruises. Florida Marine Research Publications
Series. 119 pp.
Schmidly, D.J. 1981. Marine mammals of the southeastern United States coast and the Gulf. U.S. FWS, Office
of Biological Services, Washington, DC. 163 pp. FWS/OBS-80/41.
Smith, G.B. 1976. Ecology and Distribution of Eastern Gulf Reef Fishes. Florida Marine Research Publication
No. 19.
Smith, G.G. (ed.) 1981. Cambridge Encyclopedia of Earth Sciences. Cambridge University Press, Cambridge.
In: Kennish, M.J. (ed.). 1989. Practical Handbook of Marine Science. CRC Press Inc. Boca Raton, FL. 710 pp.
Steidinger, K.A., and J. Williams. 1970. Dinoflagellates. Mem. Hourglass Cruises. Florida Marine Research
Publications Series. 225 pp.
Stewart, K.I. 1984. A study on the environmental impact offish cage culture on an enclosed sea loch. M. Sc.
Thesis. The University of Stirling. Stirling. UK.
Takashima, N., T. Aoki and T. Kitao. 1985. Epidemiological surveillance of drugresistant strains of Pasteurella
piscicida 20(2/3):209-217.
Thayer, G.W., and J.F. Ustach. 1981. Gulf Wetlands: Value, state of knowledge and research needs. In:
Proceedings of a Symp. on Environ. Res. Needs in the Gulf (GulfEX), Key Biscayne, FL, September 1979.
Atwood, D.K. (ed). Vol. MB: 2-1
Tibbs, J.F., R.A. Elston, R.W. Dickey, A.M. Guarino. 1988. Studies on the accumulation of antibiotics in
shellfish. Aquaculture International Congress and Exposition, Vancouver, B.C. 6-9 Sep, 1988, p. 64.
Toranzo, A.E., J.L. Barja, S.A. Potter, R.R. Colwell, F.M. Hetrick and J. H. Crosa. 1983. Molecular factors
associated with virulence of marine vibrios isolated from striped bass in Chesapeake Bay. Infection and
Immunity 39:1220-1227.
Toranzo, A.E., P. Combarro, M.L. Lemos and J.L. Barja. 1984. Plasmid coding for transferable drug resistance
in bacteria isolated from cultured rainbow trout. Applied and Environmental Microbiology 48:872-877.
Trees, C.C., and S.Z. El-Sayed. 1986. Remote sensing of chlorophyll concentrations in the northern Gulf.
Proceedings of SPIE, the International Society for Optical Engineering: Ocean Optics Viii. M. Blizzard (ed). Vol.
637, pp 328-334.
Turner, R.E., and Rabalais, N.N. 2013. Nitrogen and phosphorus phytoplankton growth limitation in the
northern Gulf. Aquat Microb Ecol Vol. 68: 159-169
EPA. 2016. Final Environmental Assessment. National Pollutant Discharge Elimination System (NPDES) Permit
for Eastern Gulf Offshore Oil and Gas Exploration, Development, and Production. U.S. Environmental
Protection Agency. Region 4.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 56 of 85
-------
EPA. 2012. Ocean Current and Wave Measurements at the Tampa Ocean Dredged Material Disposal Site.
Technical Memorandum. U.S Environmental Protection Agency. Region 4.
Water Protection Division. 29 pp.
EPA. 2011. 2011 Tampa Berm ODMDS Habitat Assessment. U.S. Environmental Protection Agency. National
Health and Environmental Effects Research Laboratory. Gulf Ecology Division. Technical Memorandum. 20pp.
EPA. 1994. Final Environmental Impact Statement for the Designation of an Ocean Dredged Material Disposal
Site Located Offshore Tampa, Florida. U.S. Environmental Protection Agency. Region 4. Atlanta, GA. 156 pp.
EPA. 1993. Development Document for Effluent Limitations Guidelines and New Source Performance
Standards for the Offshore Subcategory of the Oil and Gas Extraction Point Source Category. Office of Water.
EPA 821-R-93-003.
EPA. 1991. Discharges from Salmon Net-Pens to Puget Sound. Volume 1 - Technical Report. Tetra tech, Inc.
Report No. EPA 910/9-91-013a, Contract No. 68-C9-0013.
EPA. 1989. Ambient Water Quality Criteria for Ammonia (Saltwater)-1989. United States Environmental
Protection Agency publication No. EPA 440/5-88-004.
EPA. 1986. Quality criteria for water 1986. United States Environmental Protection Agency publication No.
EPA 440/5-86-001. Washington D.C.
USFDA. 1983. Environmental assessment for National Academy of Sciences/National Research Council, Drug
Efficacy Study Group. Finalization for Oxytetracycline Bureau of Veterinary Medicine. Prepared by
Environmental Impact Staff, U. S. Food and Drug Administration, Washington D.C.
Valdemarsen, T., Bannister, R. J., Hansen P.K., Holmer, M., and Ervik, A. 2012 Biogeochemical malfunctioning
in sediments beneath a deep-water fish farm. Environmental Pollution 170:
15-25.
Waldemar Nelson International, Inc. 1999. Feasibility Study - Offshore Mariculture. Report to NOAA. Award
No. NA77FL0150
Warren-Hansen, I. 1982. Evaluation of matter discharged from trout farming in Denmark. In J.S. Alabaster
(ed.), Report of the EIFAC Workshop on Fish-farm Effluents, Technical paper No. 4. Silkeborg, Denmark, 26-
28 May 1981.
Washington Department of Fisheries. 1989. Fish Culture in Floating Net Pens. Draft Programmatic
Environmental Impact Statement.
Welch, E.B. 1980. Ecological Effects of Waste Water. Cambridge University Press. Cambridge. 337 pp.
Weston, D. P. 1990. Quantitative examination of macrobenthic community changes along an organic
enrichment gradient. Marine Ecology Progress. Series 61, 233-244.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 57 of 85
-------
Weston, D.P. 1986. The environmental effects of floating mariculture in Puget Sound. Prepared by the
University of Washington, School of Oceanography for the Washington Departments of Fisheries and Ecology.
148 pp.
Weston, D.P., and R.J. Gowen. 1988. Assessment and prediction of the effects of salmon net-pen culture on
the benthic environment. Unpublished report to Washington Department of Fisheries, Olympia, WA.
Woodward-Clyde Consultants and CSA, Inc. 1984. Southwest Florida Shelf Ecosystems Study-Year 2. Report
to MMS. 14-12-0001-29144.
Yentsch, C.S. 1982. Satellite observation of phytoplankton distribution associated with large scale oceanic
circulation. NAFO Sci. Counc. Stud. No. 4. pp. 53-59.
Yoder, J.A. and A. Mahood. 1983. Primary Production in Loop Current Upwelling. In: Univ. of Maryland
Eastern Shore. 1985. Federal OCS Oil and Gas Activities: A Relative Comparison of Marine Productivity Among
the OCS Planning Areas. Draft report prepared for MMS. Coop. Agree. No. 14-12-0001-30114. 1,450 pp.
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 58 of 85
-------
Appendix A
CASS Technical Report
Environmental Modelling to Support NPDES Permitting for Velella Epsilon Offshore Demonstration
Project in the Southeastern Gulf of Mexico
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 59 of 85
-------
Coastal Aquaculture Siting and Sustainability
NCCOS/National Ocean Service
'Went of
CASS Technical Report
Environmental Modelling to Support NPDES Permitting for
Velella Epsilon Offshore Demonstration Project in the
Southeastern Gulf of Mexico
Lead Scientists: Kenneth Riley, Ph.D. and James Morris, Ph.D.
Environmental Engineer: Barry King, PE
Submitted to Jess Beck (NMFS) and Kip Tyler (EPA), July 19, 2018
This analysis uses an environmental model to simulate effluent to inform the NMFS Exempted
Fishing Permit (EFP) and EPA National Pollutant Discharge Elimination System (NPDES) Permit
for the Velella Epsilon Offshore Demonstration Project. Kampachi Farms, LLC (applicant)
proposes to develop a temporary, small-scale demonstration net pen operation to produce two
cohorts of Almaco Jack (Seriola rivoliana) at a fixed mooring located on the West Florida Shelf,
approximately 45 miles offshore of Sarasota, Florida (Figure 1; Table 1). Scientists from the
NOAA Coastal Aquaculture Siting and Sustainability (CASS) program worked with the EPA
project manager and the applicant to develop estimates of effluents and sediment related
impacts for the offshore demonstration fish farm.
A numerical production model for two cohorts of Almaco Jack was constructed based upon
anticipated farming parameters including configuration (net pen volume and mooring
configuration), fish production (species, biomass, size) and feed input (feed rate, formulation,
protein content). Using industry standard equations, daily estimates of biomass, feed rates, total
ammonia nitrogen production, and solids production (see Microsoft Excel Spreadsheet - Velella
Epsilon Production Model) were developed under a production scenario to estimate the
maximum biomass of 20,000 fish that would be grown to 1.8 kg in approximately 280 days. The
total biomass produced with one cohort and no mortality was determined to be 36,280 kg. The
density in the cage at harvest would be 28 kg/m3. Fish will be fed a commercially available
growout diet with 43% protein content. Daily feed rations range from 12 kg at stocking to a
maximum total daily feed ration equivalent to 399 kg at harvest. Maximum daily excretion of
total ammonia nitrogen is estimated at 16 kg and solids production is 140 kg. A total of 66,449
The Coastal Aquaculture Siting and Sustainability (CASS) program supports works to provide science-based decision
support tools to local, state, and federal coastal managers supporting sustainable aquaculture development The CASS
program is located with the Marine Spatial Ecology Division of the National Centers for Coastal Ocean Science, National
Ocean Service, NOAA. To learn more about CASS and how we are growing sustainable marine aquaculture practices at:
https: //coastalscience.noaa.gov/research/marine-spatial-ecologv/aquaculture/ or contact Dr. Ken Riley at
Ken.Rilev(5)noaa.gov.
-------
kg of feed will be used for production of each cohort of fish to achieve a feed conversion ratio
(FCR) of 1.8. Summary statistics were developed for each cohort and the entire project (Table
2).
Table 1. Boundary locations for the Velella Epsilon Offshore Aquaculture Project.
Location Latitude Longitude
Northwest corner 27.072360 N -83.234709 W
Northeast corner 27.072360 N -83.216743 W
Southwest corner 27.056275 N -83.216743 W
Southeast corner 27.056275 N -83.234709 W
S3'15W
83"10'W
Florida, USA
0 50 100 km
Z
in _
Layer Credits. Sources: Esn. GEBCO, NOAA, National Geographic.
HERE, Geonames org, and other contributors
Figure 1. Bathymetric map of proposed Velella Epsilon Offshore Aquaculture Project.
Page 2
-------
Table 2. Summary statistics for the Velella Epsilon Offshore Aquaculture Project.
Farming parameter
Growout duration
Total number
Individual size at harvest
Maximum biomass
Cage density at harvest
Maximum daily feed rate
Total feed used
Feed conversion ratio
Value
280 days per cohort
20,000 fish per cohort
1.8 kg
36,280 kg
28 kg/m3
399 kg
66,449 kg
1.8
In order to estimate sediment related impacts, a depositional model (DEPOMOD; Cromey et al
2002) was parameterized with data from the production model and environmental and
oceanographic data on the proposed offshore location. DEPOMOD is the most established and
widely used depositional model for estimating sediment related impact from net pen operations.
DEPOMOD is a particle tracking model for predicting the flux of particulate waste material (with
resuspension) and associated benthic impact of fish farms. The model has been proven in a wide
range of environments and is considered through extensive peer-review to be robust and
credible (Keeley et al 2013). Although this modelling platform was initially developed for
salmon farming in cool-temperate waters (Scotland and Canada), it has since been applied and
validated with warm-temperate and tropical net pen production systems (Magill et al. 2006;
Chamberlain and Stucchi 2007; Cromey etal. 2009; Cromey et al. 2012). Coastal managers
responsible for permitting aquaculture worldwide have been using this modelling platform
because it produces consistent results that are field validated and comparable (Chamberlain and
Stucchi 2007; Keeley et al 2013). It is routinely used in Scotland and Canada to set biomass (and
thereby feed use) limits and discharge thresholds of in-feed chemotherapeutants (SEPA 2005).
Further, the model output has been used to develop comprehensive and meaningful monitoring
programs that ensure environmentally sustainable limits are not exceeded (ASC 2012).
Traditionally a baseline environmental survey is used to inform water quality and depositional
models with site specific analysis of currents, tidal flows, sediment profiles, and benthic infaunal
profiles (species richness and abundance). In the absence of a survey, data were collected from
oceanographic and environmental observing systems in the vicinity of the project area. Current
data were obtained from NOAA Buoy Station 42022 along the 50-m isobath and located 45 miles
northwest of the project location (27.505 N, 83.741 W). Currents were recorded continuously
from July 2015 through April 2018. Currents were measured at 1-meter intervals from 4.0
meters to 42.0 meters below the surface (Table 3). Bathymetric data were obtained from the
Page 3
-------
NOAA Coastal Relief Model. Bathymetry was resampled to 10 x 10 meter grid cells using a
bilinear interpolation to all for use within the deposition model.
Table 3. Water column related impacts for the Velella Epsilon Offshore Aquaculture Project.
Values represent summation of daily values over a 280-day production cycle.
Parameter Value (kg)
Total solids production 23,257
Total ammonia nitrogen 2,743
Total oxygen consumption 16,612
Total carbon dioxide production 19,187
The depositional model was executed for two different production simulations that assume
maximum standing biomass and maximum feed rate, which is characteristic when the fish are at
pre-harvest size. The first simulation represented the maximum standing biomass for the Velella
Epsilon Offshore Aquaculture Project. The model was run for 365 days assuming a net pen with
a constant daily standing biomass at 36,275 kg (28 kg/m3) and a daily feed rate of 1.1 percent of
biomass or equivalent to 399 kg of feed. The second simulation doubled production to assess
sediment related impacts at higher levels of biomass and feed rates. The second simulation at a
higher level of production was intended to aid EPA in development of an environmental
monitoring program. Under the second simulation, the model was run for 365 days assuming
two net pens each with a combined constant daily standing biomass at 72,550 kg (28 kg/m3 per
net pen) and a daily feed rate of 1.1 percent of biomass or equivalent to 798 kg of feed.
Waste feed and fish fecal settling rates are important determinants of distance that these
particles will travel in the current flow. The model does not allow the settling velocity of
particles to change through the growing cycle. The values used for feed and feces represented
those that would be encountered during the period of highest standing biomass, largest feed
pellet size, and highest waste output. Each simulation assumed maximum standing biomass each
day of the simulation with a fecal settling velocity at 3.2 cm/s. Many marine fish have fecal
settling velocities ranging from 0.5 to 2.0 cm/s, while salmonids tend to have higher settling
velocities ranging from 2.5 to 4.5 cm/s. Fecal settling velocities applicable to salmon production
were used because they are well studied, validated, and allow for maximum benthic impact
assessment. Standard feed waste was estimated at 3% and the food settling velocity was 9.5
cm/s. Pelleted fish feed is the single largest cost of fish farming, and because of this expense,
farms use best feeding practices to ensure minimal loss. Feed digestibility and water content
were set at 85% and 9%, respectively, which are standards based on technical data provided by
feed manufacturers. All other model parameters were consistent with existing net pen farm
waste modelling methodologies (Cromey et al. 2002a,b) and regulatory farm modelling
standards (SEPA 2005).
Page 4
-------
(A) 4-m depth
(B) 24-m depth
(C)36-m depth
Curr««l v*lecrty
[tm/j)
¦ '60 1
¦ JO 1-60.0
¦ 40 1-500
30.1-40.0
¦ 20 1 - 30.0
¦ 10 1 - 20.0
¦ 0.0-10.0
Currant velocity
(tmi's)
¦ >60 1
¦ 50.1 -80.0
¦ 40 1-50.0
¦ 30.1-40.0
¦ 20.1-30.0
¦ 10 1-20.0
¦ 0.0-10.0
Current velocity
{cmi's)
¦f 3-601
¦ 50 1-60.0
¦ 40.1-50.0
30 1-40.0
¦ 20.1-30.0
¦ 10.1-20.0
¦ 0 0-10 0
Figure 2. Distribution of current velocities (cm/s) and direction for NOAA Buoy Station 42022
located along the 50-m isobath approximately 45 miles northwest of project location. Currents
are reported for water column depths of 4 m, 24 m, and 36 m.
Page 5
-------
Table 4. Current velocities (cm/s) for NOAA Buoy Station 42022 located along the 50-m isobath
approximately 45 miles northwest of project location. Average current velocities are reported
with standard deviation.
Depth Average current Maximum current
(m) (cm/s) (cm/s)
4 14.6 ± 8.1 83^9
10 12.8 ±8.0 80.3
20 12.2 ± 7.3 67.6
30 13.8 ±8.2 70.8
40 12.9 ± 7.6 68.7
Table 5. Model settings applied for depositional simulations of an offshore fish farm in the Gulf
of Mexico.
Input variable Setting
Feed wastage 3%
Water content of feed pellet 9%
Digestibility 85%
Settling velocity of feed pellet 0.095 m/s
Settling velocity of fecal pellet 0.032 m/s
Offshore fish farms can be managed in terms of maximum allowable impacts to water quality
and sediment that are based on quantifiable indicators. This project will be difficult to monitor
and detect environmental change because of the relatively low level of production associated
with a demonstration farm and the nature of the net pen configuration deployed and moving
about on a single point mooring.
Overall, this analysis found that the proposed demonstration fish farm is not likely to cause
significant adverse impacts on water quality, sediment, or the benthic infaunal community.
Water quality modelling demonstrated that at the maximum farm production capacity of 36,280
kg only insignificant effects would occur in the water column. We believe that the excreted
ammonia levels of 16 kg per day will be rapidly diluted to immeasurable values near (within 30
meters) of the net pen under typical flow regimes of 12.8 ± 8.0 cm s_1. Dilution models could be
used to estimate nearfield and farfield dilution as used in conventional ocean outfall systems.
Page 6
-------
However, based on our experience with offshore aquaculture installations and development of
modeling and monitoring programs, we believe that ammonia levels will be difficult to detect
beyond the zone of initial dilution.
The model does not allow the net pen or mooring configuration to move in space or time,
therefore, the model was executed at a fixed location (27.064318, -83.225726) in the center of
the project location (i.e., farm footprint). Net depositional flux was predicted in g nr2 yr1 on a
two-dimensional grid overlaid on the farm footprint. The grid size was selected such that it
would encompass the whole depositional footprint. The distribution of deposited materials
beneath the cage is a function of local bathymetry and hydrographic regime. In low current
speed environments, only limited distribution of the solids footprint occurs. As current speeds
increase, greater dispersion of solids occurs during settling resulting in a more distributed
footprint. Greater water depth at a site results in increased settling times and result in a more
distributed footprint. Solids distribution is even greater where bottom current speeds are high
causing sediment erosion and particle resuspension and redistribution.
The predicted carbon deposition and magnitude of biodeposition for the single and dual cage
scenarios were estimated over a 2.04 km by 2.04 km evaluation grid. The grid is partitioned into
cells numbering 82 east-west by 82 north-south and identified as 1-82 in both directions. The
units of the axes in both Figures 3 and 4 are these cell counts. The dimension of a single cell
therefore is 2,040m/82=24.87 m. The depositional model predicted and integrated at each one-
hour step, the total carbon that ended up in each cell in the model grid, of which there are 82 x
82 = 6,724 cells. At the end of an execution run the accumulated mass of carbon within each cell
is reported. Predicted annual benthic carbon deposition are presented in Figures 3 and 4.
Frequency histograms of the carbon deposition per cell were created to help with interpretation
of results. The depositional data derived from the frequency histograms are presented in Table
6 and 7.
Table 6 shows the distribution of carbon that results from a single net pen operated for one year
at maximum standing biomass. Of the 6,724 computational cells, 1,386 had no carbon from the
farm. Over 88% of the cells received less than or equal to 1 gram of carbon. Only 2 cells on the
farm measured more than 4 grams of carbon over the year-long simulation.
Table 7 shows the distribution of carbon that results from a two net pens operated for one year
at maximum standing biomass. Similar to the depositional model with one cage, over 75% of the
cells received less than or equal to 1 gram of carbon. One cell was calculated to receive more
than 11 grams, but it is a minuscule mass of carbon to be assimilated by a square meter of ocean
bottom.
Page 7
-------
Table 6. Frequency of carbon deposition within 6,724 cells, each measuring 619 m2, over a
4.16-km2 grid system. Values represent an annual sum of carbon deposition resulting from an
offshore fish farm with a constant standing stock biomass of 36,275 kg.
Carbon deposition
(g/m2/yr)
Occurrence
(N)
Frequency
(%)
0
1,386
20.6
0.1-1.0
4,561
67.8
1.1-2.0
620
9.2
2.1-3.0
141
2.1
3.1-4.0
14
0.2
4.1-5.0
2
0.03
Table 7. Frequency of carbon deposition within 6,724 cells, each measuring 619 m2, over a
4.16-km2 grid system. Values represent an annual sum of carbon deposition resulting from an
offshore fish farm with a constant standing stock biomass of 72,550 kg.
Carbon deposition Occurrence Frequency
(g/m2/yr) (N) (%)
0
999
14.9
0.1-1.0
4,086
60.8
1.1-2.0
903
13.4
2.1-3.0
390
5.8
3.1-4.0
200
3.0
4.1-5.0
75
1.1
5.1-6.0
40
0.6
6.1-7.0
20
0.3
7.1-7.0
7
0.1
8.1-9.0
3
0.04
9.1-10.0
0
0.0
10.1-11.0
0
0.0
11.1-12.0
1
0.01
Page 8
-------
Because of physical oceanographic nature of the site including depth and currents (>10 cm/sec),
dissolved wastes will be widely dispersed and assimilated by the planktonic community (Rensel
et al. 2017). The results of the depositional model show that benthic impacts and accumulation
of particulate wastes would not be detectable or distinguishable from background levels through
measurement of organic carbon, even when the standing stock biomass is doubled. The final
component or step in the modeling process is to predict some measure of change in the benthic
community as a result of increased accumulation of waste material. Deposition of nutrients may
result a minor increase in infaunal invertebrate population or no measureable effect whatsoever.
As part of the model assessment, benthic community impact was predicted by an empirical
relationship between depositional flux (deposition and resuspension) and the Infaunal Trophic
Index (ITI). The ITI is a biotic index that has been used to quantitatively model changes in the
feeding mode of benthic communities and community response to organic pollution gradients
(Word 1978,1980; Maurer etal. 1999). ITI scores are calculated based on predicted solids
accumulation on the seabed (g nr2 yr1). ITI scores range from 0 to 100 g nr2 yr1 and are banded
in terms of impact as:
• 60 < ITI < 100 - benthic community normal
• 30 < ITI <60 - benthic community changed
• ITI <30 - benthic community degraded.
Correlations between predicted solids accumulation and observed ITI and total infaunal
abundance have been established using data from numerous farm sites around the world.
Among the findings of these studies, a completely unperturbed benthic community at
equilibrium is considered to have an ITI of 60 and an ITI rating of 30 is the boundary where the
redox potential of the upper sediment goes from positive to negative and sulfide production
begins. A standard approach in Europe and Canada is to use an ITI of 30 as a lower limit for
acceptable impacts. In the present study with the Velella Project, the two model simulations
resulted in ITI predictions ranging from 58.67 to 58.81. The predicted ITI close to 60 suggests
that the Velella Project, as proposed, will not likely have a discernable impact on the sediment or
benthic infaunal community around the site.
In summary, the resulting model predictions covered a range of outputs representing both
submitted farming parameters and a worst-case scenario (doubled standing stock biomass) for
the Velella Epsilon Project. We conclude that there are minimal to no risks to water column or
benthic ecology functions in the subject area from the operation of the net pen as described in
Kampachi Farms, LLC applications for EFP and NPDES permits.
Page 9
-------
80
70
60
50
bJO
a
i 40
30
20
10
a « B i
250m 500m
12
11
10
9
8
7
Organic
6
Carbon
[g/m2]
5
4
3
2
1
10
20
30
60
70
80
40 50
Easting
Figure 3. Predicted annual benthic carbon deposition field beneath one net pen with a standing
stock biomass of 36,280 kg of Almaco Jack [Seriola rivoliana). Gray circle indicates center
position of the net pen. Axes indicate simulation cell numbers and deposition mass is in grams.
Page 10
-------
12
11
10
9
8
7
Organic
6
Carbon
(g/m2]
5
4
3
2
1
40
Easting
Figure 4. Predicted annual benthic carbon deposition field beneath two net pens with a standing
stock biomass of 72,560 kg of Almaco Jack (Seriola rivoliana). Gray circle indicates center
position of the net pen. Axes indicate simulation cell numbers and deposition mass is in grams.
The center of the pens is located at (27.056275 N, -83.216743 W). Predicted carbon loading was
derived from the 12-month time series relationship based on depositional flux with
resuspension.
References
ASC (Aquaculture Stewardship Council) 2017. ASC salmon standard. Version 1.1 April 2017.
Available at https://www.asc-aqua.org/wp-content/uploads/2017/07/ASC-Salmon-
Standard_vl-l.pdf
Chamberlain J., Stucchi D. 2007. Simulating the effects of parameter uncertainty on waste model
predictions of marine finfish aquaculture. Aquaculture 272: 296-311
Cromey C.J., Black K.D. 2005. Modelling the impacts of finfish aquaculture. In: Hargrave BT (ed)
Environmental effects of marine finfish aquaculture. Handb Environ Chem 5M: 129-155
Page 11
-------
Cromey, C.J., Nickell, T.D., Black, K.D. 2002a. DEPOMOD modelling the deposition and biological
effects of waste solids from marine cage farms. Aquaculture 214, 211-239
Cromey C.J., Nickell T.D., Black K.D., Provost P.G., Griffiths C.R. 2002b. Validation of a fish farm
water resuspension model by use of a particulate tracer discharged from a point source in a
coastal environment. Estuaries 25: 916-929
Cromey C.J., Nickell T.D., Treasurer J., Black K.D., Inall M. 2009. Modelling the impact of cod
[Gadus morhua L) farming in the marine environment—CODMOD. Aquaculture 289: 42-53
Cromey C.J., Thetmeyer H., Lampadariou N., Black K.D., Kogeler J., Karakassis I. 2012. MERAMOD:
predicting the deposition and benthic impact of aquaculture in the eastern Mediterranean Sea.
Aquacult Environ Interact 2: 157-176
Keeley, N.B., Cromey, C.J., Goodwin, E.O., Gibbs, M.T., Macleod, C.M. 2013. Predictive depositional
modelling (DEPOMOD) of the interactive effect of current flow and resuspension on ecological
impacts beneath salmon farms. Aquaculture Environment Interactions, 3(3), 275-291.
Magill S.H., Thetmeyer H., Cromey C.J. 2006. Settling velocity of faecal pellets of gilthead sea
bream (Sparus aurata L.) and sea bass (Dicentrarchus labrax L.) and sensitivity analysis using
measured data in a deposition model. Aquaculture 251:295-305
Maurer, D., Nguyen, H., Robertson, G., Gerlinger, T. 1999. The Infaunal Trophic Index (ITI): its
suitability for marine environmental monitoring. Ecological Applications, 9(2), 699-713.
National Geophysical Data Center, 2001. U.S. Coastal Relief Model - Florida and East Gulf of
Mexico. National Geophysical Data Center, NOAA. doi:10.7289/V5W66HPP [6/1/2018].
Rensel, J.E., King B., Morris J.A., Jr. 2017. Sustainable Marine Aquaculture in the Southern
California Bight: A Case Study on Environmental and Regulatory Confidence. Final Report for
California Sea Grant, Project Number: NAI40AR4170075.
SEPA (Scottish Environmental Protection Agency) 2005. Regulation and monitoring of marine
cage fish farming in Scotland, Annex H: method for modelling in-feed antiparasitics and benthic
effects. SEPA, Stirling.
Word, J.Q. 1978. The infaunal trophic index. Coastal Water Research Project Annual Report,
Southern California Coastal Water Research Project, El Segundo, CA, pp. 19-39.
Word, J.Q. 1980. Classification of benthic invertebrates into infaunal trophic index feeding
groups. Coastal Water Research Project Biennial Report 1979-1980, Southern California Coastal
Water Research Project, El Segundo, CA, pp. 103-121.
Page 12
-------
Appendix B
CASS Technical Report
Addendum: Environmental Modelling to Support NPDES Permitting for Velella Epsilon Offshore
Demonstration Project in the Southeastern Gulf of Mexico
ODC Evaluation
Ocean Era, Inc. - Velella Epsilon
Page 72 of 85
-------
^OATMOS^
CASS Technical Report
^rtoENT OF ^
Addendum: Environmental Modelling to Support NPDES
Permitting for Velella Epsilon Offshore Demonstration
Project in the Southeastern Gulf of Mexico
Lead Scientists: Kenneth Riley, Ph.D. and James Morris, Ph.D.
Environmental Engineer: Barry King, PE
Submitted to Kip Tyler (EPA), September 23, 2020
This report is submitted as an addendum to the report "Environmental Modelling to Support NPDES
Permitting for Velella Epsilon Offshore Demonstration Project in the Southeastern Gulf of Mexico" of
August 2018. The Environmental Protection Agency (EPA) is preparing to issue an NPDES permit for
the Velella Epsilon Offshore Demonstration Project. The applicant, Kampachi Farms, LLC (now
Ocean Era, Inc.), proposes to develop a temporary, small-scale demonstration net pen operation to
produce a single cohort of Almaco Jack (Seriola rivoliana) at a fixed mooring located on the West
Florida Shelf, approximately 45 miles offshore of Sarasota, Florida. With this addendum, scientists
from the NOAA Coastal Aquaculture Siting and Sustainability (CASS) program continued to work
with the EPA NPDES permitting program to develop estimates of farm discharge deposition on the
seabed and surrounding benthic community. Specifically, the farm simulation was executed for five
years at the maximum stocking density, with the predicted feed and fish waste daily contributions. The
most recent version of DEPOMOD modelling software (i.e., NewDEPOMOD) was used to calculate
the distribution and deposition of solid materials at the project location.
Current data were obtained from NOAA Buoy Station 42022 along the West Florida Shelf at the 50-m
isobath and located 45 miles northwest of the project location (27.505 N, 83.741 W). The buoy is
owned and data are collected by the University of South Florida Coastal Ocean Monitoring and
Prediction System with support from the U.S. Integrated Ocean Observing System. Lacking five
continuous years of water column flow data at the site, a single year of current data from the original
simulation was used to produce the assumed current profile at the project location. Given that single
year current data was used for this model, year-to-year variability in oceanographic patterns that are
associated with changing climate and weather patterns, water temperature, and storm tracks (e.g.,
hurricanes) are not evaluated.
As previously reported, bathymetric data were obtained from the NOAA Coastal Relief Model.
Bathymetry was resampled to 25 x 25 meter grid cells using a bilinear interpolation to all, for use
within the deposition model. The characterization of the site and composition of benthic surfaces were
informed by U.S. Geological Survey offshore surficial sediment data (usSEABED) that describes
seabed characteristics, including textural, geochemical, and compositional information for the Gulf of
Mexico. The benthic surfaces for the project location were also informed by acoustic survey and sub-
bottom profile data included with the applicant's Baseline Environmental Survey (BES). Sediment
samples, including core or grab samples, were not collected or analyzed as part of the BES. Without
-------
knowing explicitly the hydraulic roughness of the benthic surface at the project location, the model
was run (as previous) with the assumption of a smooth benthic surface characteristic of unconsolidated
sediments (coarse to fine grain sand bottom) such as those common on the West Florida Shelf.
Modelling with a smooth benthic surface and reduced roughness tends to lower the bed shear stress
and increase resuspension.
The model does not allow the net pen or mooring configuration to move in space or time, therefore,
the model was executed at a fixed location (27.064318, -83.225726) in the center of the project
location (i.e., farm footprint). The model domain also remained as reported. The model domain was
set to encompass the whole initial depositional footprint under average current velocities estimated at
20 cm/s and with particles settling at rates faster than 0.75 cm/s. The dimensions for the model domain
are standards required by the Scottish Environmental Protection Agency for marine aquaculture
operations. The domain also captures reasonable efficiency in processing large data sets or long time-
series data (i.e., model requires 24-36 hours to process). The predicted carbon deposition and
magnitude of biodeposition were estimated over a 2.04 km by 2.04 km evaluation grid. The grid is
partitioned into square cells with sides measuring 24.87 m and cells numbering 82 east-west by 82
north-south with cells identified as 1-82 in both directions. The modelling software reports the average
solids and carbon within each cell as grams per square meter at the moment it is queried, typically at
the end of the simulation period.
This model execution did not allow the settling velocity of particles to change through the growing
cycle. The values used for feed and feces represented those that would be encountered during the
period of highest standing biomass, largest feed pellet size, and highest waste output from the net pen
operation. Each simulation assumed maximum standing biomass each day of the simulation with fecal
settling and food settling velocities applicable to salmon production at 3.5 and 9.5 cm/s, respectively.
The values for fecal settling velocity may have implications for dispersion. For this study, a
conservative settling velocity (3.5 cm/s) was used to assess the maximum extent of fecal deposition on
benthic surfaces. Knowledge of the physical properties of fish feces under net pen conditions is
rudimentary. Most reported literature addresses the fecal stability, density, and settling velocity (3.5
cm/s) of farmed salmon (Reed et al. 2009). Data on fecal settling velocity for Ambeijack (Seriola spp.)
are scarce. Amberjack feces are shapeless and unstable in the water column (e.g., lacking
cohesiveness). The species has a reported fecal settling velocity of about 1.6 cm/s owing to its smaller
size and density (Fernandes and Tanner 2008).
The model was run for 1,825 days assuming a net pen with a constant daily standing biomass at
36,288 kg (22.85 kg/m3) and a daily feed rate of 1.1 percent of biomass or equivalent to 399 kg of
feed. Standard feed waste was estimated at 3%. The model simulates release of fecal and feed particles
from a net pen at hourly increments. Multiple particles are released representing different mass
percentages and different settling velocities defined in the set-up files. The particles are all tracked
throughout the domain at each time step over the duration of the simulation. Particles that are
transported out of the domain boundary at 1,020 m away at the closest, are lost and removed from the
calculations. Only masses of material that remain in the domain at the moment a surface is queried and
2
-------
recorded are reported. At high current velocity sites, such as this project location where the average
flow is 13 cm/s and peaking at 67 cm/s at 4 meters above the seabed (Figure 1), the bulk of settleable
solids from the aquaculture operation are dispersed outside of the simulation domain. It is expected
that these solids would continue to be oxygenated and transported along benthic surfaces downstream
where currents allow for deposition and resuspension. This particulate organic carbon would be
readily available and consumed by bacteria and benthic infauna.
SOFTWARE UPDATES
NewDEPOMOD (version 1.3, released July 2020) and previous versions of DEPOMOD are computer
models that have been developed by the Scottish Association of Marine Science to inform siting,
permitting, and regulation of marine fish farms. The model predicts the impact of farm deposition on
the seabed in order to optimize the operation of aquaculture sites to match the environmental capacity.
The Scottish Environmental Protection Agency has used the software for over a decade in direct
support of their aquaculture permitting standards.
NewDEPOMOD incorporates a range of features in its newest release including:
• improved predictive abilities for offshore aquaculture projects including the capacity to use
three-dimensional hydrodynamic flow field data;
• an updated and characterized resuspension process using data from an extensive set of field
measurements of erosion, resuspension and transport at farm sites;
• a new model framework for sediment deposition which allows the model to include varying
bathymetry; and
• a model that produces conservative estimates of the holding capacity of a proposed site that can
be tuned using data collected once a farm enters production to improve predictions, also useful
for planning expansion of an existing farm.
ESTIMATING DEPOSITION AND MASS FLOW TO THE BENTHOS
Mass flows of solids onto the seabed were estimated from the mass of cultured fish on the farm and
the specific rate, which they are fed (Table 1). We developed a model for a 1,296-m3 net pen1 with a
stocking density of 28 kg/m3, which will yield a biomass of 36,288 kg. An estimated 399.17 kg of feed
will be applied per day at a feeding rate of 1.1 percent of body weight. During permitting, the
applicants changed the net pen design to a larger volume, however the biomass within remained the
same at 36,288 kg which is the keystone value for the waste dispersion simulation.
1 After completion of modelling, it was noted by the EPA that minor changes occurred with submission of the Ocean
Era permit application. The net pen configuration changed as did the size of fish at harvest. The discrepancy in net
pen volume (1,296 m3 vs 1,588 m3] and fish size (1.8 kg vs. 2.0 kg), and the implications on model results are
negligible.
3
-------
With a feed moisture content of 9% and an estimated 3% food waste rate, the feed dry mass lost from
the net pen is: [ 399.17 kg feed * (100%-9% kg dry feed / kg feed) * 3% kg dry feed lost/kg dry feed]
= 10.89 kg dry feed lost to the environment each day, or 0.454 kg per hour.
Since the feed is measured as 49% carbon, the flux is: 10.89 kg dry feed wastage * 0.49 kg carbon/ kg
dry feed = 5.34 kg carbon per day from feed.
Similarly, for the fecal mass produced with the assumed 9% feed moisture and 85% utilization:
[(399.17 kg feed - 3% lost (11.97 kg)) * 15% fecal mass/mass of solid feed ingested * 91% kg solid
feed / kg feed] = 52.85 kg of fecal solids per day, or 2.2022 kg per hour.
Fecal matter is measured as 30% carbon and yields: 52.85 kg of fecal solids * 0.30 kg carbon / kg of
fecal solids = 15.85 kg carbon per day
Combining the flux masses for solids and carbon an estimated 63.74 kg of solids and 21.19 kg of
carbon are released into the environment each day from the demonstration project.
Table 1. Summary statistics for the Velella Epsilon Offshore Aquaculture Demonstration Project.
Farming parameter Value
Initial Total number 20,000 fish
Individual size at harvest 1.8 kg
Maximum biomass during growout 36,288 kg
Net pen density at harvest 22.85 kg/m3
Maximum daily feed rate 399 kg
Total feed used 66,449 kg
Feed conversion ratio 1.8
Table 2 reports the mass flows of solids and carbon from the Velella Epsilon Offshore Aquaculture
Demonstration Project within the simulation domain. The bulk of released solids and their carbon are
lost from the domain, carried into the far-field by currents. Comparing values of solids in Table 2, the
simulation predicts that 3.63% of the solids remain within the simulation domain after five years.
There are periods in the water flow cycles when solids accumulation is variable in the domain, as
illustrated in Figure 2. The masses on the final day approximate the average concentrations.
4
-------
Table 2. Mass flows of solids and carbon from the Velella Epsilon Offshore Aquaculture
Demonstration Project within the simulation domain at the end of 5 years.
Model Parameters and Simulation Results Value
Mass of feed applied (5 years) 728,481.60 kg
Mass of feed wastage (5 years ) 19,887.57 kg
Mass of feed wastage carbon (5 years) 9,744.89 kg
Mass of fecal materials (5 years) 96,454.61 kg
Mass of fecal carbon (5 years) 28,936.38 kg
Total mass dry solids released / day 63.75 kg
Total mass dry solids released / year 23,268.43 kg
Total mass dry solids released / 5 years 116,342.17 kg
Total mass carbon released / day 21.20 kg
Total mass carbon released / year 7,736.25 kg
Total mass carbon released / 5 years 38,681.27 kg
Solids balance (Total solids within domain after 5 years) 4,224.87 kg
% solids retained inside domain 3.63 %
% solids exported outside domain 96.37 %
Carbon balance (Total carbon within domain after 5 years) 1,406.13 kg
% carbon retained inside domain 3.64 %
% carbon exported outside domain 96.36 %
At the project location, water velocities are typical for currents along the West Florida Shelf. Figure 1
illustrates the water velocity at the Velella site at a depth of 36.7 meters or approximately 4.0 meters
above the seafloor. Currents at this project location will likely re-suspend feed wastes and fecal
materials transporting these solids across the seafloor. The simulation software calculates the
movement of the released solids using the particle characteristics, the nature of the seafloor, and the
velocity of the water body in the proximity of the seafloor.
5
-------
80
70
60
1 50
'V
J 40
V
>
a
20
10
0
0 20 40 60 80 100 120 140 160 ISO 200 220 240 260 280 300 320 340 360
Time (d)
Figure 1. Water currents and flow velocity measured at 4 m above the seafloor.
Figure 2 illustrates the fate of the remaining solids within the domain over the five-year simulation,
calculated from the total mass of released solids, minus the total mass of solids that are exported out of
the simulation domain. The figure shows that over the five-year simulation solids on the seafloor
within the domain reach an equilibrium, at an average total mass of 4,013 kg. The leading edge of the
plot illustrates the point material accumulates on the seabed where it will eventually resuspend leading
to more material being transported away from the depositional site as currents reach the shear force
threshold. During the first days of operation little material was available for resuspension, all the
while, new material was being added at a constant 63.75 kg per day.
NewDEPOMOD reports distribution of solids as surface plots of either solids or carbon, it does not
distinguish between the sources of the carbon, either feed or fecal, and are combined. In Figure 3, the
distribution of carbon is plotted for the final hour of the five-year simulation. Within the software,
each surface plot generates its own scale to coincide with the colors on the map. The reader should use
caution when comparing plots.
6
-------
0 200 400 600 800 1000 1200 1400 1600 1800 2000
Time (d)
Figure 2. Predicted solids deposition beneath one net pen with a standing stock biomass of 36,288 kg
of Almaco Jack (Seriola rivolicma) after five-year farm simulation.
Figure 3 shows the carbon distribution over the 2,040 x 2,040 meter Velella simulation domain on day
number 1,830. The highest concentration of aquaculture sourced carbon on the site is 4.35 g/m2 Most
noticeable in this deposition prediction map is the wide distribution of carbon over 4 km2 with small
accumulations and no areas of excessive concentrations. Frequency histograms of the carbon
deposition per cell were created to help with interpretation of results. The depositional data derived
from the frequency histograms are presented in Table 3.
This wide dispersion and low concentration of carbon created the average Infaunal Trophic Index (ITI)
score for this final overall benthic surface of 58.96 out of 60. As previously reported, a predicted ITI
of close to 60 suggests that the Velella project will not likely have a discernable impact on benthic
communities around the project location. Similar to other studies reporting ITI as a measure of benthic
impacts from net pen operations, we do not expect significant impact on sediment redox potential or
sulfide production. For example, Hargrave (2010) and Keeley et al. (2013) extensively documented
correlations among the carbon deposition rate, redox potential, hydrogen sulfide concentration,
interstitial dissolved oxygen, and ITI. We believe that the Velella project will present challenges for
monitoring and detecting environmental impacts on sediment chemistry or benthic communities
because of the circulation around the project location and the small mass flows of materials from the
net pen installation. As the simulation illustrates, the high energy environment at the site and the mass
7
-------
flow of materials equilibrates at a resident total mass of waste products at approximately 4,000 kg with
local masses never exceeding more than 43.4 g solids per square meter for a single sample point over
the 5 year simulation.
CONCLUSION
There are minimal to no risks to sediment chemistry or benthic ecology functions in the project area
from the operation of the net pen as described in the Ocean Era, LLC application for an NPDES
permit.
60
a
13
ti
o
£
80
70
60
50
40
30
20
10
Organic
3 Carbon
(g m- yr1)
Easting
Figure 3. Predicted benthic carbon deposition field beneath one net pen with a standing stock biomass
of 36,288 kg of Almaco Jack (Seriola rivofiana) after five years. Grey circle indicates center position
of the net pen. Axes indicate simulation cell numbers and carbon deposition mass is in grams.
8
-------
Table 3. Frequency of carbon deposition within 6,724 cells, each measuring 619 m2, over a 4.16-km2
grid system. Values represent an annual sum of carbon deposition resulting from an offshore fish farm
with a constant standing stock biomass of 36,288 kg.
Carbon deposition
(g/m2/yr)
Occurrence
(N)
Frequency
(%)
0
1,508
22.43
0.1-1.0
4,526
67.32
1.1-2.0
559
0.08
2.1-3.0
111
1.65
3.1-4.0
16
<0.01
4.1-5.0
4
<0.01
REFERENCES
Fernandes, M. and J. Tanner. 2008. Modelling of nitrogen loads from the farming of yellowtail
kingfish Seriola lalandi (Valenciennes, 1833). Aquae. Res. 39: 1328-1338.
Hargrave, B.T. 2010. Empirical relationships describing benthic impacts of salmon aquaculture.
Aquae. Env. Inter. 1(1): 33-46.
Keeley, N. B., C. J. Cromey, E. O. Goodwin, M. T. Gibbs, and C. M. Macleod. 2013. Predictive
depositional modelling (DEPOMOD) of the interactive effect of current flow and resuspension on
ecological impacts beneath salmon farms. Aquae. Env. Inter. 3(3): 275-291.
Reid, G. K., M. Liutkus, S. M. C. Robinson, T. R. Chopin, and others. 2009. A review of the
biophysical properties of salmonid faeces:implications for aquaculture waste dispersal models and
integrated multi-trophic aquaculture. Aquae. Res. 40: 257-273
9
-------
Appendix: Time-series simulation of predicted benthic carbon deposition beneath one net pen
with a standing stock biomass of 36,288 kg of Almaco Jack (Seriola rivoliana). The reader should
use caution comparing plots. The software generates a new legend for each plot in the time
series. The scale and color ramp varies with each surface plot.
Day 450
10
-------
Appendix: Time-series simulation of predicted benthic carbon deposition beneath one net pen
with a standing stock biomass of 36,288 kg of Almaco Jack (Seriola rivoliana). The reader should
use caution comparing plots. The software generates a new legend for each plot in the time
series. The scale and color ramp varies with each surface plot.
Day 540
|
\
m
¦" . "***!~ y
X \ \ V
r
RJr+Lri.
IVf rJ
¦JL". 1
mr'-i "*Vi
-rlr-^" -So ¦
?3S
b • i a
< * * * - »
s»I«, /
•»
* f '¦* *
•J W
¦¦
¦ ii
• a
4 1 »
g cartx>n/m2
mi
IHIIIII
-4J ->
1 '11 -iO 0
Depth (m)
Day 810
1IREH'
Kf.
Svprij^-" ":-rra
' 'i
Br -¦ •
1 .
3u i ,
ie • |
• « u
g cart>on/m2
42 >n -at •» «
Depth (m)
g cartx>ivm2
-4J •)!
-------
Appendix: Time-series simulation of predicted benthic carbon deposition beneath one net pen
with a standing stock biomass of 36,288 kg of Almaco Jack (Seriola rivoliana). The reader should
use caution comparing plots. The software generates a new legend for each plot in the time
series. The scale and color ramp varies with each surface plot.
Day 1260
%
yj
!¦
12
-------
Appendix: Time-series simulation of predicted benthic carbon deposition beneath one net pen
with a standing stock biomass of 36,288 kg of Almaco Jack (Seriola rivoliana). The reader should
use caution comparing plots. The software generates a new legend for each plot in the time
series. The scale and color ramp varies with each surface plot.
Day~1440
SffaftB I
3 ¦ 4
¥ *
g cartx>n/m2
-t} -SI -21
Depth (m)
Day 1530
^ m
E#, *
Bwr1 ¦ ¦
m
a-SBE
•rrfiA
g carbon/m2
4i -ji -n -i«
Depth (m)
Day 1710
HKirrii -
r-. • > •
k ¦ ¦¦ M ii|
1 * * 1 L * .
.J
\ " .3 1 •
WBrt -
I A J 8
» si -te. tek
'
EF4t*» * *
m | _ •
LJ | "-pi . •
('&> s:'
hfv^L'VZij i
Vs. yoc^jP.
IB*
¦ |
1
Hi
0
4 0
g carbon/m2
llll
¦¦mm
¦41 -3
>1 *U -10 0
Depth (m)
13
------- |