Scientific Review of the Draft Environmental Impact Statement: Drakes Bay Oyster Company Special Use Permit (2012)

CHAPTER 2

Framing of the Draft Environmental Impact Statement

While reviewing the scientific information and analysis in the Draft Environmental Impact Statement (DEIS), the committee found common issues across resource categories that are related to how the DEIS is framed and merit discussion upfront.

Distinguishing Potential Impacts of Alternatives B, C, and D

Under the National Environmental Policy Act (NEPA), the agency analyzes the impacts of a “range of reasonable alternatives” that for this DEIS were developed “taking into consideration the results of internal discussions, review of public scoping comments, and consultation with local, state, and other federal agencies. Development of the action alternatives also was informed by the scope and scale of the existing Drakes Bay Oyster Company (DBOC) operations and facilities.”¹ Although the DEIS states that the action alternatives (B, C, and D) refer to “differing levels of onshore facilities and infrastructure and offshore operations,”² with the exceptions of the larger permitted area for the Manila clam under alternatives B and D, and of the onshore facilities described for alternative D, the major difference among the alternatives is in the level of harvest permitted.

The level of harvest does not provide a clear distinction among alternatives B, C, and D. In mariculture, as in other forms of farming, operations are typically scaled in terms of three metrics: (1) the footprint of the area planted (2) the cultivation (bed or growing) area; and (3) the amount of product harvested (i.e., yield or production). Level of effort is assumed to scale with each of these metrics. The amount of product harvested (referred to as “production” in the DEIS; e.g., 585,277 lbs of oysters and 684 lbs of Manila clams harvested by DBOC in 2010)³ has the greatest potential variability of these three metrics as a function of environmental conditions, shellfish diseases, harmful algal blooms, predation, and market conditions. For example, high interannual variability in oyster condition, indicative of the influence of environmental conditions on productivity, has been observed in Willapa Bay (Schoener and Tufts, 1987).

Hence differentiating alternatives B, C, and D primarily in terms of permitted levels of production (450,000-850,000 lbs/yr), not in terms of the footprint or acreage of growing areas or levels of effort,⁴ introduces ambiguity with respect to assessing the relative impacts of the three action alternatives. Will interannual variations in production reflect differences in maximum production permitted, area planted and cultivated, or the effects of variable growing conditions? If the latter interpretation is correct, differences between B, C, and D would not reflect level of effort, and the alternatives would effectively be the same with respect to offshore activities. And indeed, the DEIS reaches the conclusion that impact levels of alternatives B, C, and D would be similar for each resource category relative to the no action alternative.

The National Park Service (NPS) would have greater ability to manage the footprint of DBOC offshore activities if they distinguished alternatives based on the actual mariculture footprint and how much of the permitted areas could be used as growing areas. In principle, DBOC could substantially change the mariculture footprint relative to current conditions independently of the production limit. However, there are also drawbacks to distinguishing alternatives based on areas where mariculture is allowed, or on the amount of effort allowed (for instance, hours of motorboat activity). For example, if DBOC planted a bed and then lost it to a bad batch of seed, they would not be able to replace it under a scheme where activities are limited by level of effort.

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¹ DEIS, p. 57.

² DEIS, p. 1.

³ DEIS, Table 2.1.

⁴ Permitted areas available for cultivation specified in the Special Use Permit are 1,083 acres for alternative B and 1,087 acres for alternative D (DEIS, p. 58-60).

Baseline Conditions

The DEIS acknowledges that two baselines were used in assessing impacts:⁵

“For the purposes of this document … The baseline against which the no-action alternative is assessed is generally existing conditions … The action alternatives, on the other hand, are … assessed using the no-action conditions as the baseline condition. In other words, the analysis of the action alternatives may be documented by contrasting the expected future conditions under each action alternative to the expected future conditions under the no-action alternative.”

In other words, for alternative A, the DEIS assesses the expected impacts associated with the removal of DBOC’s operations. The expected impacts are compared to the existing conditions, i.e., the continued operation of the shellfish farm. By contrast, impacts associated with alternatives B, C, and D are compared to the less certain, expected future conditions under alternative A (considered the “no action” alternative).

The committee recognizes that, in NEPA practice, the “no action” alternative is usually considered the “baseline” under which current environmental conditions are compared. In these situations, environmental conditions would not change under a “no action” alternative. However, in the case of the DBOC, if the Secretary of the Interior took no action, the Special Use Permit (SUP) would expire and alternative A would be implemented, which would change current conditions. Given that the environmental impacts associated with existing conditions are known with greater certainty than those associated with alternative A (potential future conditions), assessing the impacts of action alternatives B, C, and D against “no action” alternative A increases the level of uncertainty in conclusions about the impacts of alternatives B, C, and D. Also, the use of two baselines introduces asymmetry into the analysis such that the impacts of “no action” alternative A cannot be compared to the impacts of the action alternatives (alternatives B, C, and D). This becomes a particular problem in the Summary of Environmental Consequences⁶ which presents the potential impacts of the four alternatives as if they were comparable, even though the impacts of the “no action” alternative A are assessed using a different baseline than that of the action alternatives (B, C, and D).

Scaling Impacts on Drakes Estero and Changes in Ecosystem Conditions

The DEIS⁷ defines a “local” impact as one that would occur within the general vicinity of the project area and a “regional” impact as one that would affect localities, cities, or towns surrounding the Seashore. The DEIS⁸ also defines a “direct” impact as one caused by an action that “occurs at the same time and place” and an “indirect” impact as one “caused by an action but is later in time or farther removed in distance, but still reasonably foreseeable.” For seven of the resource categories examined in this study (wetlands, eelgrass, wildlife and wildlife habitat, special status species, coastal flood zones, water quality, and soundscapes), the committee used the spatial scale as they interpreted the definitions of “direct”, i.e., the impact is direct when it causes a change in ecosystem state on the same scale as the impact source, and “indirect” if it is expressed on the scale of the Drakes Estero ecosystem.⁹ Thus, the potential spatial footprints of DBOC operations (onshore facilities, culture racks and bags, and motor boat corridors) would correspond to local scales of impact. In this context, the total area permitted for onshore operations would be less than 1% of the Drakes Estero watershed and the total area designated for cultivation (138 acres under alternatives B, C, and D) would be ~5.5% of the entire Estero (including Estero de Limantour) and about 10% of the intertidal and subtidal acreage in the potential wilderness area (Table 2.1). Actual utilized areas would likely be smaller. For example, the footprint of racks (7 acres) used in recent years are estimated to cover 13% of the subtidal culture beds. When considered in

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⁵ DEIS, p. 234.

⁶ DEIS, Table ES-4.

⁷ DEIS, p. 235.

⁸ DEIS, p. 235.

⁹ These definitions of “direct” and “indirect” are not relevant to the socioeconomic category since direct impacts are assessed in terms of human uses on larger scales (market value of shellfish, employment, recreational use of the Seashore, etc.).

terms of habitat acreage in the project area, the footprint of rack culture is about 1% of the eelgrass acreage. It was in this context that the committee considered whether the direct scale of impact on Drakes Estero resources was reflected in potential adverse changes to the structure and function of the Drakes Estero ecosystem as a whole (indirect impacts). In so doing, the committee understands that the acreage for bag and rack culture, and associated motorboats and human activity, move from place to place within permitted areas as the DBOC attempts to optimize production. Consequently, the spatial footprints integrated over time are larger than the footprint at any given time.

TABLE 2.1. Spatial extent of Point Reyes National Seashore and the Drakes Estero ecosystem with acreage designated for DBOC’s operations (all acreages came from the DEIS, except for wilderness and potential wilderness¹⁰). DBOC’s operations take place on uplands near the head of Schooner Bay and in tidal wetlands and subtidal waters of Drakes Estero. In addition to rack and bottom bag cultures, floating bags are also deployed; these are predominantly located in intertidal culture beds.

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¹⁰ FR Doc.99-29779, available at: www.nps.gov/pore/parkmgmt/upload/lawsandpolicies_fr_doc_99_29779.pdf.

¹¹ The 50 acres corresponds to polygons within which propeller scars are found (NRC, 2009).

¹² These values assume that motorboat usage will stay roughly the same under the three action alternatives as assessed by the NPS for boat activity in 2010 (used for “current” in the table). However, this area could change for the action alternatives under which DBOC would follow an NPS-approved vessel transit plan.

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