animal/insect entrance through the drain. A suitable cap should be placed on the well to

prevent tampering or the entry of any foreign materials. A lock should be installed on the

cap to provide security. To prevent corrosion or jamming of the lock, a protective cover

should be used. Care should be taken when using lubricants such as graphite or petroleum 

based sprays to lubricate the lock, as lubricants may introduce a potential for sample

contamination. Locks should not be lubricated on the day the well is sampled, and gloves

that are worn while lubricating the lock should be changed prior to initiating other activities

at the well.

To guard against accidental damage to the well from facility traffic, the

owner/operator should install concrete or steel bumper guards around the edge of the concrete

apron. These should be located within 3 or 4 feet of the well and should be painted orange

or fitted with reflectors to reduce the possibility of vehicular damage.

The use of flush to ground surface completions should be avoided because this design

increases the potential for surface water infiltration into the well. In cases where flush to 

ground completions are unavoidable, such as in active roadways, a protective structure such

as a utility vault or meter box should be installed around the well casing. In addition,

measures should be taken to prevent the accumulation of surface water in the protective

structure and around the well intake. These measures should include outfitting the protective

structure with a steel lid or manhole cover that has a rubber seal or gasket, and ensuring that

the bond between the cement surface seal and the protective structure is watertight.

6.6

Well Surveying

The location of all wells should be surveyed by a licensed professional surveyor (or

equivalent) to determine their X Y coordinates as well as their distances from the units being

monitored and their distances from each other. A State Plane Coordinate System, Universal

Transverse Mercator System, or Latitude/Longitude should be used, as approved by the

Regional Administrator. The survey should also note the coordinates of any temporary

benchmarks. A surveyed reference mark should be placed on the top of the well casing, not

on the protective casing or the well apron, for use as a measuring point because the well

casing is more stable than the protective casing or well apron (both the protective casing and

the well apron are more susceptible to frost heave and spalling). The height of the reference

survey datum, permanently marked on top of the inner well casing, should be determined

within  0.01 foot in relation to mean sea level, which in turn is established by reference to an

established National Geodetic Vertical Datum. The reference marked on top of inner well

casings should be resurveyed at least once every 5 years, unless changes in ground water flow

patterns/direction, or damage caused by freeze/thaw or desiccation processes, are noted. In

such cases, the Regional Administrator may require that well casings be resurveyed on a more

frequent basis.

November 1992

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