N.H. Code Admin. R. Env app B
40 CFR §141.2 :
Conventional filtration treatment means a series of processes including coagulation, flocculation, sedimentation, and filtration resulting in substantial particulate removal.
Direct filtration means a series of processes including coagulation and filtration but excluding sedimentation resulting in substantial particulate removal.
Flocculation means a process to enhance agglomeration or collection of smaller floc particles into larger, more easily settleable particles through gentle stirring by hydraulic or mechanical means.
Legionella means a genus of bacteria, some species of which have caused a type of pneumonia called legionnaires disease.
Sedimentation means a process for removal of solids before filtration by gravity or separation.
Virus means a virus of fecal origin which is infectious to humans by waterborne transmission.
40 CFR §141.91 Recordkeeping requirements:
"Any system subject to the requirements of this subpart shall retain on its premises original records of all sampling data and analyses, reports, surveys, letters, evaluations, schedules, State determinations, and any other information required by §§141.81 through 141.88. Each water system shall retain the records required by this section for no fewer than 12 years."
N.H. Code Admin. R. Env app B