Section Env-Wq 1708.09 - Significant or Insignificant Determination(a) Any discharge or activity that is projected to use 20% or more of the remaining assimilative capacity for a water quality parameter, in terms of either concentration or mass of pollutants, or volume or flow rate for water quantity, shall be considered a significant lowering of water quality.(b) The department shall not approve a discharge or activity that will cause a significant lowering of water quality unless the applicant demonstrates, in accordance with Env-Wq 1708.10, that the proposed lowering of water quality is necessary to achieve important economic or social development in the area where the waterbody is located.(c) Subject to (e), below, any applicant proposing an activity that will cause an insignificant lowering of water quality shall not be required to demonstrate that the activity is necessary to provide important economic or social development, provided the applicant implements best management practices to minimize degradation.(d) Activities allowed under (c), above shall include, but not be limited to: (1) Short term or intermittent discharges such as hydrostatic testing of pipelines, fire pump test water, and uncontaminated stormwater discharges or site clean-up activities;(2) Permanent discharges such as uncontaminated noncontact cooling water, uncontaminated groundwater seepage, or unchlorinated or dechlorinated swimming pool water;(3) Facilities whose nonpoint source runoff is controlled through the use of best management practices; and(4) Any discharge or activity that is projected to use less than 20% of the remaining assimilative capacity for a water quality parameter, in terms of either concentration or mass for pollutants or volume or flow rate for water quantity.(e) If the department determines based on the following factors that the effect of a discharge results in a greater impact to the water quality than that normally found in insignificant discharges, the department shall determine that the proposed activity or discharge is significant, regardless of the proposed consumption of the remaining assimilative capacity, and require the applicant to demonstrate, in accordance with Env-Wq 1708.10, that a lowering of water quality is necessary to achieve an important economic or social development: (1) The magnitude, duration, and spatial extent of the proposed change in water quality;(2) The cumulative lowering of water quality over time resulting from the proposed activity in combination with previously approved activities;(3) The possible additive or synergistic effects of the activity in combination with existing activities;(4) The magnitude of the mass load independent of the total assimilative capacity or change in receiving water pollutant concentration;(5) The toxic or bioaccumulative characteristics of the pollutant(s) in question;(6) The potential to stress sensitive biological resources such as indigenous species, rare species, and threatened or endangered species and their habitat;(7) The potential to stress sensitive recreational uses or water supply uses; or(8) The quality and value of the resource.N.H. Code Admin. R. Env-Wq 1708.09
(See Revision Note #1 at chapter heading for Env-Wq 1700) #7151, eff 12-10-99; ss by #9034, INTERIM, eff 12-10-07; ss by #9162, eff 5-21-08 (See Revision Note #2 at chapter heading for Env-Wq 1700)
Amended by Volume XXXVI Number 49, Filed December 8, 2016, Proposed by #12042, Effective 12/1/2016, Expires 12/1/2026.