Notional Field Development Final Report - EBN

EBN Notional Field Development Plan
In Section 6.2 – Comprehensive Water Management, we presented detailed information about water
treatment options and their costs.
4.7.5 Naturally Occurring Radioactive Material (NORM)
Some soils and geologic formations contain low levels of radioactive material. This naturally occurring
radioactive material (NORM) emits low levels of radiation, to which everyone is exposed on a daily basis.
Radiation from natural sources is also called background radiation.
In addition to the background radiation at the earth’s surface, NORM can also be brought to the surface
in the natural gas production process. When NORM is associated with oil and natural gas production, it
begins as small amounts of uranium and thorium within the rock. These elements, along with some of
their decay elements, notably radium226 and radium228, can be brought to the surface in drill cuttings
and produced water. Radon222, a gaseous decay element of radium, can come to the surface along with
the shale gas.
When NORM is brought to the surface, it remains in the rock pieces of the drill cuttings, remains in
solution with produced water, or, under certain conditions, precipitates out in scales or sludges. The
radiation from this NORM is weak and cannot penetrate dense materials such as the steel used in pipes
and tanks.
Figure 4-73. Drilling pipe can become NORM contaminated
The principal concern for NORM in the oil and gas industry is that, over time, it can become
concentrated in field production equipment and as sludge or sediment inside tanks and process vessels
that have an extended history of contact with formation water. Because the general public does not
come into contact with oilfield equipment for extended periods, there is little exposure risk from oilfield
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