Massachusetts Aquaculture Strategic Plan Appendix F - Categories of Aquaculture Projects in the Commonwealth of Massachusetts

In developing a process for monitoring the environmental impact of aquaculture projects in Massachusetts' marine and coastal waters, the Monitoring Subgroup relied heavily upon the previous experience of the State of Maine, which in turn adapted its protocols from initiatives already underway in the State of Washington.

The model proposed for Massachusetts would assign a proposed aquaculture project to one of four categories:

Category 1 aquaculture projects are low-impact, bottom-culture systems with no structures suspended within the water column that could inhibit other uses of overlying waters and with no addition of food or other inputs to the ecosystem. A prominent example of Category 1 aquaculture is the bottom culture of bivalve mollusks. Category 1 aquaculture should require minimal baseline evaluation of the site over and above that required to evaluate whether the site is appropriate in the context of traditional uses, levels of productivity anticipated, and so forth. Operational monitoring once a Category 1 system is in place should require little effort beyond annual inspection by local and/or regulators to ensure that the level of use is as described in the permit "Order of Conditions". An annual report on productivity at a Category 1 site would be required, with submission to the appropriate state agency. This annual report should include, but not be limited to, information on the number of seed deployed and the amount of crop harvested. These data would be maintained as proprietary and confidential.

Category 2 projects involve more intensive use of the physical space, with structures suspended, e.g., within cages or on ropes, within the water column or in the intertidal zone, thereby limiting access to the overlying waters. Hanging (suspended) culture of bivalves is an example of Category 2 aquaculture. No additional inputs (feeds or other therapeutic agents) are permitted at a Category 2 site. Baseline monitoring information required for a Category 2 aquaculture initiative consists of all the information required for Category 1 projects, plus data to evaluate the potential impact of the suspended structures. These additional data include:

1. A detailed design plan, including engineering specifications, if appropriate, for the facility, including concise drawings of equipment to be deployed temporarily and/or permanently into the environment.

2. A description of the proposed site, including measurements of depth, tidal current velocities, and of benthic habitat (including video diver survey), specifically identifying sediment type, submerged vegetation, and in-fauna.

3. Information on known uses of the proposed site by endangered species and discussion of potential impact of the proposed aquaculture project on endangered species.

Monitoring requirements for a Category 2 site include an annual site visit and a biannual evaluation of the benthic environment under the site (including video diver survey). Entanglements of protected species will be reported within 24 hours to the Division of Marine Fisheries. In addition, an annual report on site productivity, plus documentation of all animal entanglements and user conflicts throughout the reporting period, shall be required. These data will be maintained as proprietary and confidential.

One issue not addressed by the Maine model, which may warrant consideration in Massachusetts' waters, concerns placement of suspended structures in shallow waters overlying submerged vegetation, where shading of sunlight may be a problem.

Category 3 aquaculture operations are land-based and intensively managed facilities such as shellfish or finfish hatcheries or recirculating culture systems. Facility discharges are contained, concentrated and remotely deployed into the environment. In considering monitoring programs for Category 3 culture systems, the Working Group noted that regulations addressing point-source discharges are currently well established and that guidelines/regulations are clearly outlined as part of the National Pollutant Discharge Elimination System (NPDES) permitting process administered through the Army Corps of Engineers. The tools for environmental monitoring of Category 3 culture systems are thus already in place, although it will be necessary in Massachusetts to classify the effluent from these systems as "agricultural effluent" and and to apply those regulations which are required for the discharge of such waste effluent to all Category 3 aquaculture facilities.

Category 4 aquaculture is defined by the addition of structures to the water column as well as inputs of organic and inorganic materials. The prototypical Category 4 aquaculture enterprise involves floating netpen culture of finfish. Because Category 4 aquaculture is the most intensive level of field-deployed, in situ aquaculture, the most stringent environmental monitoring is associated with this level of aquaculture development.

Category 4 aquacultural enterprises affect the environment primarily on account of the addition of organic and inorganic products (feed, medications) to the water. Addition of feed and the subsequent production of feces contribute to overall nutrient loading in the water column as soluble products leach from food and feces and as fine particulate material persists in suspension in the water column. Although nutrient enrichment of the receiving water may present a problem, particularly on a cumulative basis, within a confined water body, the overwhelming impact from category 4 aquaculture activities usually derives from hypernutrification of the benthos. Settling solids (both feed and feces) can result in unacceptable impacts such as azoic areas adjacent to or under pens primarily due to benthic anoxia, outgassing events which liberate toxic gases such as methane and hydrogen sulfide, establishment of fungal mats (Beggiatoa sp.) within the netpen impact area, and hyperdominance of infauna extending beyond the footprint of the netpen system.

The State of Maine has developed a comprehensive site evaluation protocol for category 4 aquaculture facilities. Environmental assessment begins with a baseline evaluation at the beginning of the site permit application process and continues with yearly site inspections performed by agents from the State, coupled with production and distribution of an annual environmental report by the aquaculturists.

The following baseline and operational monitoring guidelines, derived directly from the Maine model, are suggested for Category 4 aquaculture projects in Massachusetts:

Baseline Field Survey/Monitoring: All permitted proposals will require on-site field studies to characterize existing environmental conditions as reference data for future comparisons after operation start-up. Elements of the baseline field monitoring program for Category 4 projects include video-recorded observations collected by divers, hydrographic information, water quality measurements and benthic data on sediment quality as well as macrobiological community structure).

Aquaculture lease regulations shall specify that applicants may do more than one site evaluation, but at least one evaluation must be conducted and completed between May 1st and September 30th before a lease is granted

1. Diver survey. A diver shall survey the proposed site to determine the relative abundance of the macrofauna/flora, sediment types, and other unique features of the substrate including the presence of Beggiatoa or like species, epibenthic algal layers, prominent ledges, depressions, etc., prior to operation start-up. This survey shall be documented with a video camera. The dive shall be conducted along the axis of the current and through the center of the proposed lease area. The diver shall document sediment types and features, noting erosional or depositional areas. Relative abundance of flora/fauna shall be documented in accordance with the following very general categories: abundant (seen occasionally within the diver's view), common (seen occasionally throughout the dive, maybe patchy), rare (only seen once or in a few places throughout the dive).

One copy of the video tape on standard VHS tape format shall accompany the application. Although video format is preferred, photographs taken at 10-m intervals may be submitted, if video is not available. A brief narrative describing appropriate reference points shall accompany the tape or photos. All visual documentation shall include the dates on which data were collected.

2. Hydrography. Hydrographic data shall be collected, including measurements of current speed and direction, in order to predict the fate of fecal material and/or unconsumed feed. The current shall be measured at three depths: surface, suspended structure bottom, and 1 m off the ocean floor. A 15-minute sample shall be collected at each of these 3 depths every hour for 12 consecutive hours, representing one complete tidal cycle. An average tide should be selected; spring or neap tides should be avoided. Subsurface current meters are preferred. However, flow meters may be used with concurrent surface direction estimated. The data (hard copy as well as disc) shall be delivered in tabular format and shall include the date and tide predictions for that day.

3. Water quality. Water quality samples shall be collected, including dissolved oxygen profiles during peak stratification periods (usually August or September). A detailed dissolved oxygen profile, consisting of 10 equally spaced samples over the entire vertical depth, shall be measured at the center of the site. This is the same location where hydrographic data shall be collected. Water samples may be collected or an electronic membrane probe may be used to measure concentrations. Temperature and salinity profiles are also required from the same samples and depths. These data will determine percent saturation and evidence of stratification. Samples shall be taken within one hour of slack low water (preferably in the early morning).

Water column dissolved oxygen acceptable methodology and quality assurance procedures, required to substantiate compliance with water quality standards, are discussed in the following paragraph.

Although the preferred method for quantifying dissolve oxygen is the "Winkler Titration" (azide modification), of Standard Methods, the use of the membrane electrode method is acceptable, considering the multiple depths required for the profile. The zero and standard calibration methods described in the most current edition of Standard Methods and the instrument manufacturer's instructions shall be followed. Air calibration readings shall be recorded at the beginning and end of each interval when the meter is on. One duplicate reading per profile shall be taken and reported to verify that the meter is reading consistently. Furthermore, at the beginning and end of each sample season, calibration curves comparing the probe to Winkler readings for at least four dissolved oxygen concentrations ranging from less than 20% to 100% saturation shall be constructed. If more than one meter is used, curves shall be developed for each meter. These curves shall be submitted with all data.

4. Benthos. Benthic monitoring shall involve two components: sediments and infauna.

a. Sediments. The applicant shall prepare a sediment loading plan which includes the number and location of sediment samples to be collected for geological, chemical, and biological analyses. Single sediment cores shall be collected for a set of samples which are representative of bottom characteristics of the proposed site. The precise design, number and location are not specified here because of the variety of potential structure configuration and sizes. However, a systematic sampling design (sampling at equidistant intervals) which covers the entire area of proposed site, plus 60 m in each tidal direction (ebb and flood) is required.

The sampling grid design and protocol shall be coordinated with the appropriate state agencies (DEP and DMF) to ensure that the data collected are acceptable and consistent. Sediment cores will identify sediment grain size (percent gravel, sand, silt, clay), the depth of the redox discontinuity layer, the depth of the unconsolidated organic layer, and total organic carbon (TOC). Single cores collected using a Plexiglas type corer according to the proposed sampling plan shall be inserted to resistance or to 15 cm, whichever is less. The depth of the discontinuity layer shall be measured from the surface. The depth of the unconsolidated organic layer can also be measured visually with a Plexiglas corer. Grain size analysis shall be performed using the wet sieving method described in Buchanon, or according to a similar procedure. Standard sieve sizes for gravel, sand, silt and clay shall be used. Full analysis of the silt clay fractions may be calculated as the difference in the dry weight between the original sample and the sum of the sieve fractions down to the 0.062 mm sieve (very fine sand). The fraction in each sieve shall be reported in grams (dry weight) and percent of total (dry weight), including the total dry weight of the initial sample.

The unconsolidated material and the top 2 cm of inorganic sediments shall be collected for TOC analysis. The applicant shall ensure that a minimum of 30 g is collected for analysis. Multiple cores (which include the top 2 cm of inorganic material), if warranted, shall be required. TOC shall be analyzed using methods described in the Puget Sound Estuary Program, Hedges and Stearn or Verardo et al.

b. Infauna. Infaunal samples shall be sieved through a 0.5 mm sieve (collection techniques are presented with metric measurements) and organisms identified to species or the lowest practical taxonomic level. Single cores shall be collected according to the proposed sampling plan along the axis of the current. Cores must be inserted to resistance or to 15 cm, whichever is less, and the depth of the core shall be reported.

Individual benthic infaunal cores collected by a diver shall have an area of at least 81 sq. cm (a 4-inch diameter PVC pipe will suffice). Alternatively, cores may be collected from a grab or box-type corer having an area of at least 0.1 sq. m. If subsamples are taken from a grab or box-type corer for the sediment analysis and the remaining sample used for biological analyses, no more than 1/4 of the surface of each sample can have been removed for the sediment analysis.

Operational (Long-Term) Monitoring: After an aquaculture permit has been issued, the following operational monitoring program shall be required. The objective of these monitoring requirements is to identify effects of aquatic farms on sediments and water quality. It will also provide data with which to review current environmental requirements for possible future modifications.

1. Diver survey. A diver survey shall be conducted twice a year, once between April and May and once between October and November. Except as provided below, diver surveys shall be documented with continuous video footage within the footprint of the aquaculture structures and shall extend 60 m beyond the ends of the system along the axis of the primary current. The diver shall document sediment types and features, noting erosional or depositional areas, as well as macroflora/fauna observed, including their relative abundance. Relative abundance shall be characterized approximately as follows: abundant (seen occasionally within the diver's view); common (seen occasionally throughout the dive, maybe patchy); rare (only seen once or in a few places throughout the dive). Video format is preferred, but photographs taken at 10 m intervals may be submitted if video is not available. A brief narrative describing reference points shall accompany the tape or photos. Diver surveys conducted by the DMF (done once per year to corroborate videos presented by the permit holder) may be used to satisfy this monitoring requirement, if they are available. All visual documentation shall include the dates on which data were collected.

2. Water quality. Three water quality samples shall be collected and analyzed for dissolved oxygen, temperature, and salinity every two weeks from June 1 through October 30. Sampling stations shall be placed such that down-current samples will represent water that has passed through the greatest concentration of suspended structures. Water quality samples shall be taken at mid-depth, i.e., if the structure is 6 m deep, the sample shall be collected 3 m from the surface. The three stations to be sampled shall be located 100 m up-current of the operation, 100 m down-current of the operation, and within 5 m down-current from the structures. Also, during the month of August, a once annually, detailed dissolved oxygen, temperature, and salinity profile, consisting of ten equally spaced samples over the entire vertical depth, shall be measured at each of the three stations listed above.

Water samples may be collected, or an electronic membrane probe may be used to measure the concentrations. Temperature and salinity measurements are also required from the same samples and depths. These data will determine percent saturation and evidence of stratification. Samples shall be taken within one hour of slack low water (preferably in the early morning). Methodologies to be used are as described above in the discussion of baseline monitoring, water quality.

3. Benthos. Analysis of the benthos shall be required during the first period of peak inputs. This generally coincides with the first harvest at the end of the growing season, when multiple age classes are in the water. After this initial survey, monitoring will be required every other year. As with the protocol for baseline monitoring, there are two components to the operational benthic monitoring protocol: sediments and infauna. Procedures and methodologies are as described previously under baseline monitoring/benthos.

Additional operational monitoring requirements may be necessary as the Commonwealth's aquaculture initiative develops and especially to ensure coordination with the Massachusetts Marine Monitoring Program.

Reporting requirements, operational monitoring: By December 15th of each year the leaseholder shall submit the following information to DMF:

1. Spring and fall diver survey reports and videos.
2. Water quality monitoring data from June 1 through October 30.
3. Benthic survey report for the year.
4. Summary data of total feeds fed, stocking density of organisms, and total production of culture system for the year in question (confidentiality maintained).
5. Data (substance, quantity, date(s) added, and location) of all substances introduced into the culture system other than animal feed.

To corroborate the data reported above for a Category 4 aquaculture system, an annual site visit, including a diver survey, shall be conducted by the Massachusetts DMF during the summer.

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Published: September 1995