Section Env-Wq 1508.11 - Other Stormwater Treatment Practices(a) An applicant who wishes to use a stormwater treatment practice not specified in these rules shall submit a written request to the department for approval of the practice.(b) The request shall include the following:(1) A copy of the plan(s) submitted pursuant to Env-Wq 1503.05(c)(3) with the location where the practice is proposed to be used clearly marked;(2) A narrative description of the proposed practice, together with any diagrams or schematics that are helpful to understanding the proposed practice, including how the proposed practice meets the requirements specified in (f), below;(3) If the proposed practice includes components for which the manufacturer has provided a design, installation, and/or operations manual, a copy of such manual(s);(4) A description of the operation and maintenance procedures required to ensure the practice remains functional;(5) A description of any advantages of the proposed practice over the practice(s) specified in these rules, including in particular environmental and operational benefits;(6) A description of the protocol used for the field-based assessment of the practice, including the length of time the practice has been in use; and(7) If the practice has been used in other states or provinces having climate and geological features like those found in New Hampshire, a list of where the practice has been used and, for each such state or province, the name and daytime telephone number and, if available, an e-mail address, of an official at a state or provincial agency who has knowledge of, and who can be contacted regarding, the practice.(c) The department shall approve the proposed stormwater treatment practice if the information provided by the applicant demonstrates that:(1) The field-based assessment was performed in accordance with a protocol which produces the same quality and quantity of data as the protocols established by the University of New Hampshire Stormwater Center, the Technology Acceptance and Reciprocity Partnership, or the Washington State Department of Ecology Technology Assessment Protocol; and(2) The proposed practice meets the criteria specified in (f), below.(d) The department shall notify the applicant of its decision in writing. If the request is denied, the notice shall specify the reason(s) for the denial.(e) If the department approves the proposed practice, the approval shall: (1) Require compliance with Env-Wq 1507.07 relative to long-term maintenance;(2) Require annual inspections of the practice with an evaluation of the functionality of the practice, and the annual submission to the department of a report of the findings of the inspection and evaluation if the information submitted pursuant to (b), above, does not show the proposed practice to have operation longevity of at least 5 years in the field; and(3) Include any other conditions that are necessary to ensure the practice meets the criteria specified in (f), below.(f) A proposed stormwater treatment practice shall be approved only if the practice:(1) Captures and treats the WQV or WQF;(2) Achieves a minimum removal rate of 80% of total suspended solids at the WQF;(3) Does not discharge floatable debris, including oil and petroleum products, for all flow rates up to the design WQF, either alone or in combination with pretreatment; and(4) Has automatic operation during runoff events.N.H. Admin. Code § Env-Wq 1508.11
(See Revision Note #1 at chapter heading for Env-Wq 1500) #9343, eff 1-1-09
Amended by Volume XXXVII Number 32, Filed August 10, 2017, Proposed by #12342, Effective 8/15/2017, Expires 8/15/2027.Amended by Number 41, Filed October 12, 2023, Proposed by #13758, Effective 9/28/2023, Expires 9/28/2033 (formerly Env-Wq 1508.10) (see Revision Note #4 at chapter heading for Env-Wq 1500).