Section Env-Wq 402.25 - Response to Exceedances(a) If any regulated contaminant is detected by the permittee's monitoring at a concentration that exceeds the applicable AGQS, the permittee shall: (1) Within 10 days of receiving the test results that show the exceedance, notify the department of the exceedance;(2) Within 21 days of receiving the test results that show the exceedance, test water for the regulated contaminant that exceeds the AGQS from each private or public drinking water supply well within 1,000 feet of the location where the exceedance occurred;(3) Report the results of the testing required by (2), above, to the department within 45 days of collecting the samples;(4) For exceedances of contaminants other than 1,4-dioxane, perfluorooctanoic acid, perfluorooctane sulfonic acid, perfluorononanoic acid, or perfluorohexane sulfonic acid, or any combination thereof, from a facility that discharges treated wastewater to groundwater, prepare, submit, and implement a written response plan in accordance with (b) through (g), below, to ensure that groundwater quality criteria are not violated at the boundary of the groundwater discharge zone; and(5) For exceedances of 1,4-dioxane, perfluorooctanoic acid, perfluorooctane sulfonic acid, perfluorononanoic acid, or perfluorohexane sulfonic acid, or any combination thereof, from a facility that discharges treated wastewater to groundwater, proceed as specified in Env-Wq 402.251.(b) If the testing done pursuant to (a)(2), above, shows the presence of a regulated contaminant in a private or public drinking water supply well at a concentration that exceeds the applicable AGQS and the department determines that it is more likely than not that the permitted wastewater discharge is the source of the regulated contaminant, the permittee shall:(1) Expand the testing of public and private drinking water wells beyond 1,000 feet as necessary to determine the extent of the exceedance of the applicable AGQS in drinking water supplies;(2) Within 21 days of receiving the test results obtained pursuant to (1), above, submit a proposed response plan to the department that evaluates the relative costs and benefits of:a.Installing treatment to remove the contaminant from the water supplied from the well; orb.Provide alternate water to those served by the drinking water supply by:1.Providing bottled water as an interim mitigation measure until a long-term water supply alternative is provided; and2.Providing a long-term alternative water supply by:(i) Installing, testing, and maintaining a point-of-entry water treatment system at each structure served; or(ii) Connecting each structure served to a public water system.(c) Subject to (d), below, the response plan shall include the following:(1) All actions necessitated by (b), above, if applicable;(2) Inspection and audit of activities and procedures at the facility to determine possible sources of groundwater contamination;(3) Further site investigation to evaluate additional potential sources of groundwater contamination and the extent of their impact on groundwater quality;(4) Modification of facility operation as needed to eliminate the cause of the exceedance;(5) Removal or containment of the source of the groundwater contamination; and(6) Groundwater quality restoration.(d) If facility operations cannot be modified to eliminate the cause of the exceedance or if the groundwater quality cannot be restored, the response plan shall include a schedule of activities that will be implemented for facility closure.(e) The permittee shall: (1) Submit the response plan to the department within 60 days of receiving the test results that show the exceedance; and(2) Implement the response plan within 30 days of department approval.(f) Within 90 days of receiving a proposed response plan, the department shall notify the permittee in writing of whether it has approved the plan. If the department does not approve the plan, the notice shall specify the reason(s) for the disapproval.(g) The department shall approve the response plan if the department determines that the plan, if implemented as specified, is expected to:(1) Remove, treat, or contain the source(s) of groundwater contamination to prevent the additional release of regulated contaminants to groundwater;(2) Achieve compliance with AGQS;(3) Ensure safe drinking water and otherwise protect human health and the environment; and(4) Contain and confine groundwater contamination within the limits of the groundwater discharge zone, delineated in accordance with Env-Wq 402.23(a).N.H. Code Admin. R. Env-Wq 402.25
(See Revision Note at part heading for Env-Wq 402) #8955, eff 7-26-07
Amended by Volume XXXVI Number 10, Filed March 10, 2016, Proposed by #11036, Effective 3/1/2016, Expires 3/1/2026.Amended by Volume XXXVIII Number 28, Filed July 12, 2018, Proposed by #12553, Effective 9/1/2018, Expires 9/1/2028.Amended by Volume XXXIX Number 32, Filed August 8, 2019, Proposed by #12836, Effective 9/30/2019, Expires 9/30/2029.