Title of Regulation: 9VAC25-900. Certification of Nonpoint Source Nutrient Credits (amending 9VAC25-900-91).

Statutory Authority: § 62.1-44.19:20 of the Code of Virginia.

Effective Date: January 1, 2021.

Agency Contact: Debra Harris, Department of Environmental Quality, 1111 East Main Street, Suite 1400, P.O. Box 1105, Richmond, VA 23218, telephone (804) 698-4209, FAX (804) 698-4346, or email debra.harris@deq.virginia.gov.

Background: The Certification of Nonpoint Source Nutrient Credits regulation (9VAC25-900) regulates the process for the certification of nonpoint source nitrogen and phosphorus nutrient credits and assures the generation of those credits. The final regulation, including 9VAC25-900-91, was adopted by the State Water Control Board on December 13, 2019. As part of the approval to adopt, the board deferred submittal of 9VAC25-900-91 for final publication in the Virginia Register of Regulations until such time as (i) the Department of Environmental Quality receives approval of 9VAC25-900-91 pursuant to Executive Order No. 14 (2018) and (ii) the earlier of the date the guidance is submitted to the Registrar of Regulations for publication pursuant to § 2.2-4002.1 of the Code of Virginia or September 1, 2020. The deferral was to provide time for the department to seek input from stakeholders regarding the development of guidance on how to implement the requirements of 9VAC25-900-91. On May 26, 2020, the department received approval of 9VAC25-900, including 9VAC25-900-91, pursuant to Executive Order No. 14 (2018). The guidance regarding implementation of 9VAC25-900-91 is still under development. As the board's action requires submittal by September 1, 2020, 9VAC25-900-91 was submitted for final publication.

Summary:

The provisions establish requirements for exchange of nonpoint source nitrogen and phosphorus nutrient credits to ensure local water quality is not contravened when these exchanges occur.

9VAC25-900-91. (Reserved.) Exchange of credits.

A. Exchange of a credit released by the department is subject to the provisions of § 62.1-44.15:35, 62.1-44.19:15, or 62.1-44.19:21 of the Code of Virginia.

B. Where necessary to ensure compliance with local water quality requirements, the exchange of a credit released by the department is conditioned as follows:

1. Within the Chesapeake Bay Watershed, the exchange of credits within an area subject to an approved local TMDL for total phosphorus or total nitrogen with allocations more stringent than the Chesapeake Bay Watershed TMDL shall be limited to those credits generated upstream of where the discharge reaches impaired waters.

2. Within the Southern Rivers watersheds, the exchange of credits within an area subject to an approved local TMDL for total phosphorus or total nitrogen shall be limited to those credits generated upstream of where the discharge reaches impaired waters.

3. Within an area with waters impaired for dissolved oxygen, benthic community, chlorophyll-a, or nutrients but with no approved local TMDL, the exchange of credits shall be limited to those credits generated in accordance with the following hierarchy:

a. Upstream of where the discharge reaches impaired waters if credits are available;

b. Within the same 12-digit HUC if credits are available;

c. Within the same 10-digit HUC if credits are available;

d. Within the same 8-digit HUC if credits are available;

e. Within an adjacent 8-digit HUC within the same tributary if credits are available; or

f. Within the same tributary.

C. The hierarchy of subdivision B 3 of this section shall not apply when:

1. The department determines through issuance of a VPDES permit that local water quality cannot be protected unless exchange of credits are restricted to upstream of where the discharge reaches impaired waters; or

2. It has been demonstrated to the department's satisfaction that:

a. The water quality impairment is not likely caused by nutrients; or

b. The use of credits would not reasonably be considered to cause or contribute to the impairment.