Section Env-Dw 303.16 - Source Evaluation for Sources Not Using External Force For any source where no pumping or other external force will be used to collect water, the source evaluation shall be conducted as follows:
(a) The source evaluation shall address both the natural high flow conditions and the natural low flow conditions of the source;(b) At least 2 monitoring wells shall be placed to meet the objectives of the source evaluation. Additional monitoring wells shall be required when preliminary information indicates they are necessary to meet the objectives of the source evaluation as specified in Env-Dw 303.14(c);(c) The evaluation shall be conducted for 10 continuous days, as follows:(1) Monitoring during the first 3 days shall be conducted with no withdrawal of water from the source;(2) Monitoring from the beginning of day 4 through the end of day 8 shall be conducted while water is withdrawn from the source at the desired permitted production volume; and(3) From the beginning of day 9 to the end of day 10, recovery monitoring shall be conducted with no withdrawal from the source;(d) Water collected during the evaluation shall be discharged at a location that ensures the water cannot provide recharge to the source pursuant to a temporary groundwater discharge permit obtained under Env-Wq 402;(e) The flow rate from the source shall be measured over a period of one minute or less at least twice daily at intervals of approximately 12 hours, using a calibrated flow meter, weir, flume, or similar device;(f) Water levels in the source and in the monitoring wells shall be measured twice daily, at the same time the flow rate measurements are done;(g) If the source ceases to flow during the withdrawal period specified in (3)b., above, the time that flow ceases and the time it starts again shall be recorded, and measurement of water levels shall replace flow measurements during any time the source is not flowing;(h) Weather conditions, including rainfall amounts at the site, shall be recorded throughout the evaluation;(i) Water levels in any surface water located within 500 feet of the source shall be measured to the nearest 0.01 foot and recorded at least twice daily during the evaluation, at the same time the flow rate measurements are done;(j) The horizontal distance between each observation well, surface water measurement location, and the source shall be measured to the nearest foot;(k) The vertical elevation of the observation wells, surface water, and source shall be established to the nearest 0.01 foot and referenced to the National Geodetic Vertical Datum of 1929 or subsequent national datum such as the North American Vertical Datum of 1988;(l) Water level, flow rate, and date and time of measurement shall be tabulated and plotted;(m) A regional groundwater flow net shall be constructed which shows flow directions in the horizontal and vertical planes and indicates hydraulic boundaries and recharge sources;(n) Data collected pursuant to (a) through (m), above, shall be used to refine the protected area at the desired permitted production volume for 180 continuous days without recharge from rainfall; and(o) Water quality sampling shall be as follows: (1) A water quality sample shall be taken within the first 2 hours after initiating the evaluation;(2) A second water quality sample shall be taken at the mid-point of the evaluation;(3) A third water quality sample shall be taken during the last day of the evaluation;(4) The samples shall be analyzed by a laboratory that has been accredited to perform drinking water testing in New Hampshire pursuant to Env-C 300 or equivalent standards established by EPA;(5) The samples collected pursuant to (1) and (2), above, shall be analyzed for volatile organic compounds, iron, manganese, pH, specific conductance, hardness, chloride, sodium, nitrate, radon, and coliform bacteria;(6) The sample collected pursuant to (3), above, shall be analyzed for radon, 1,4 dioxane, and those contaminants required to be monitored in accordance with Env-Dw 707 through Env-Dw 713; and(7) Additional samples shall be collected and analyses performed if necessary to establish a contamination source control program in accordance with Env-Dw 303.23.N.H. Code Admin. R. Env-Dw 303.16
(See Revision Note at part heading for Env-Dw 303) #8998, eff 9-29-07
Amended by, Volume XXXVI Number 14, Filed April 7, 2016, Proposed by #11059, Effective 4/1/2016, Expires 4/1/2026.