N.H. Code Admin. R. We 602.16 – Setback Reductions: Special Methods of Construction for Bedrock Wells

(a) For a bedrock well that does not comply with the setback requirements of We 602.06 through We 602.12, as applicable, a water well contractor shall:
1. (1) For a bedrock well with a minimum setback requirement of 75 feet, install casing in accordance with the Table 602-1:
  Table 602-1 Minimum Casing Length Where a 75-foot Setback is Required
  Horizontal Setback (ft.)
  Minimum Length of Casing (ft.)
  75 or greater
  20
  70-74
  27
  65-69
  37
  60-64
  45
  55-59
  51
  50-54
  56
  45-49
  60
  40-44
  63
  35-39
  66
  30-34
  69
  25-29
  71
2. (2) For a bedrock well with a minimum setback requirement of 50 feet, install casing in accordance with the Table 602-2:
  Table 602-2 Minimum Casing Length Where a 50-foot Setback is Required
  Horizontal Setback (ft.)
  Minimum Length of Casing (ft.)
  50 or greater
  20
  45-49
  22
  40-44
  30
  35-39
  36
  30-34
  40
  25-29
  43
3. (3) Grout the casing as specified in We 602.05; and
4. (4) Seal the casing to a minimum depth of 10 feet into competent bedrock.
(b) For purposes of determining minimum casing length for setbacks to effluent disposal areas or septic tanks, in accordance with Table 602-1, if a well is located at a higher elevation than the effluent disposal area, the difference in elevation shall be added to the minimum required casing length.

Source. (See Revision Note at chapter heading for We 600) #12083 eff 3-1-17