March 27, 2024
On behalf of MAREC Action (informally, “Mid-Atlantic Renewable Energy Coalition”), thank you for the opportunity to comment on Version 1.0 of the Virginia Stormwater Management Handbook.
MAREC Action is a coalition of utility-scale solar, wind, and battery storage developers, wind turbine and solar panel manufacturers, and public interest organizations dedicated to promoting the growth and development of renewable energy in the Mid-Atlantic region. MAREC Action provides expert guidance and advocacy on policy and regulatory issues, as well as a unified voice for the industry.
MAREC Action encourages DEQ to work collaboratively with each segment of the solar industry when creating or revising regulations related to erosion and sediment control, and stormwater management, as each party has distinct experience and expertise on site design, construction, and operations. While several MAREC Action members are vertically integrated companies - responsible for greenfield development, construction, and ultimately owning and operating the facility – others specialize in one stage of the development process. Thus, we encourage DEQ to maintain an open dialogue with many industry trade groups to ensure that a diversity of firms can participate in regulatory workgroups or respond to agency inquiries related to best management practices and advancements in technology.
While the primary purpose of a solar facility is to deliver affordable, clean electricity, MAREC Action encourages DEQ to view solar deployment as a potential tool to providing long term water quality benefits to the Commonwealth of Virginia and the Chesapeake Bay. Sites developed according to best management practices – such as the prompt stabilization of soils during construction, or revegetation of the project area with native species - can deliver significant ecosystem services, especially when compared to the previous land use. For example, Walston et al (2021) observed that a solar facility with native vegetation or turf grass planted underneath panels can result in a 95% and 19% increase, respectively, in sediment and water retention when compared to row crop agriculture.[1] Similarly, solar deployment typically reduces the quantity and frequency of pesticides and fertilizer application on a project site – in turn, providing water quality benefits to the local watershed.[2] Given such potential ecosystem services benefits, solar deployment will have a role in helping Virginia attain its Total Maximum Daily Load and other regional stormwater management goals.
First, MAREC Action applauds DEQ for undergoing through extensive process of updating and consolidating the Virginia Erosion and Sediment Control and Stormwater Management Handbooks, as well as other guidance documents issued by DEQ. DEQ Director Rolband has affirmed the agency’s intent to streamline existing regulations and accelerate the permitting process. Indeed, clear and transparent permitting guidelines will be an essential element to achieving Virginia’s energy goals.
Given the long development timeline associated with solar project development, it is paramount new regulations and guidance shaping solar deployment apply only to projects in the earliest stages of development. MAREC Action observed that DEQ took these development timelines into account when the agency applied the revised stormwater management calculations to solar projects that receive their System Impact Study (SIS) after December 31st, 2024. This affords future solar projects time to consider the revised regulations when designing panel areas, stormwater management BMPs, and buffers. In some cases, developers may be required to lease additional land to accommodate the new guidance.
Below are MAREC’s comments on specific sections in the manual.
MAREC Action requests clarification on whether the section below applies only to slopes, or to all areas after the site clearing and development phase.
Therefore, maintenance of a sufficiently stabilized surface (> 75% intact mulch or temporary vegetation) on slopes (> 5%) during the site clearing and development phase is important and should be followed by rapid establishment of a permanent perennial stand of vegetation sufficient to meet assumptions for unconnected surface water flow following storm events as enhanced by the panel arrays and drip lines.
Based on observations of regulations in other states, MAREC Action is not aware of other jurisdictions with similar standards related to soil decompaction. In particular, 6.3.1.5.3 mentions requiring “designers of any site to adjust post development curve numbers by one HSG to account for compaction during construction.” Increasing the HSG classification for post-development land covers by one factor will result in considerable impacts on post-construction runoff computations for solar facilities. As A.3.7.2 D. provides numerous favorable alternatives, MAREC Action requests clarity that these alternatives remain allowable within the proposed revisions. DEQ may consider a requirement to test HSG after the mitigation work is complete in order to verify water quantity goals are achieved.
Further, MAREC Action encourages DEQ to not assume soil will remain compacted for prolonged durations. Soil may naturally decompact, especially as the operational lifetime of a solar facility typically exceeds 30 years.
MAREC Action appreciates DEQ’s thoughtful consideration to the relationship between widespread adoption of single-axis tracker technology and managing stormwater runoff. However, due to the varying physical limits of tracking panels, it is not possible to achieve a fully vertical position, as suggested during heavy rain events. This requirement should be amended to specify “to the extent possible according to manufacturer specifications”. Failing to adhere to the wind/hail/safety stow angles will invalidate multi-year term warranties and carries a higher risk for catastrophic equipment damage.
Requiring that at least 25% of the stand be legume species is a workable requirement for temporary stabilization or initial installation, however, the ratio is difficult to maintain for the full duration of operations as these species can die off quickly. Furthermore, routine nitrogen fertilization not only represents a significant cost, and would encourage the presence of undesirable species and result in water quality impacts. To achieve a cost-effective and practical nitrogen-fixing requirement, the provision could be set at requiring legumes as 25% of seed mix by percentage PLS.
While in most applications, the minimum disconnection length between two rows of solar panels can be equal to the width of each row. However, MAREC encourages an allowance for alterations here is needed, with additional mitigation to offset the variance, approved by consultation with the Department.
Based on updated phosphorus targets for new development, and pollutant loads for both impervious cover and managed turf, there is a significant increase in the total phosphorus load reduction for ground-mount solar projects across the Commonwealth. MAREC respectfully requests that DEQ clarify the acceptable use of redevelopment vs. new-development on the appendix spreadsheet. For example, if the existing land use is row-crop or pastureland, the redevelopment version of VRRM v4 would result in significantly less of an impact as compared to the new-development version.
Second, MAREC requests clarification on the allowable maintenance operations for solar facilities in the mixed-open land cover category. Guidance and previous comment responses indicates that DEQ intends for solar facilities to be categorized under mixed-open in areas where grading and compaction are not applicable. However, this would require sites to be mowed less than 4 times per year. With the standard vegetation proposed on-site, this may not be feasible to achieve the native and deep-rooted vegetation that successfully improves hydrologic conditions.
This concludes MAREC’s comments on Version 1.0 of the Virginia Stormwater Management Handbook. Thank you for your consideration.
Sincerely,
CommentID: 222381