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egulations for drilling oil and gas wells. The salt section in the subject well is protected
by two strings of casing instead of casing and cement. Any casing leaks should be
detectable in the bradenhead at the surface. BLM has schedl:':e well for periodic
bradenhead testing. However, had the cementing of the oil s een witnessed, this
violation could have been prevented.
BLM 43 CFR Part 3160 is a general order, and is less stringent for drilling in the
Potash Area than the OCD order. In instances such as this, oil and gas operators on
federal lands must comply with the OCD order because the BLM attempts to administer
OCD rules.
Before an oil and gas operator obtain approval for a well in the Potash Area,
he is required to notify all potash lessees within one mile of the proposed location. The
potash lessee can oppose the well based on minable potash reserves to be determined by
BLM. All applications to drill are reviewed by BLM and approved or denied based on
the quality of potash under and around the location. If the well is to be drilled on state or
private land, BLM and the State Land Office must forward their approval to OCD before
the well can be drilled. Several proposed locations along the north and east boundary of
WIPP have been denied because of potash reserves.
Flows of water have been encountered in the salt section in and near waterfloods
in Lea County the closest of which is approximately 15 miles northeast of WlPP. These
flows ranged from a few to several thousand barrels per day. The source of flows was,
for the most part, from water injected into oil-bearing formations for the purpose of
enhanced oil recovery. Through a combination of old improperly cemented and plugged
wells and excessive injection pressures, water probably escaped from the injection
interval and migrated upward to the salt section. When these waters reached the salt, it
appears they migrated horizontally through the salt. This resulted in collapsed pipe in
producing wells and sometimes large uncontrolled flows of salt water in wells being
drilled nearby. It should be pointed out that large-volume flows of water and air were
encountered in some wells in Lea County long before enha!lCed oil recovery was
instigated. This could indicate that some of the brine flows encountered were natural
occurrences.
Only a small portion of Lea County is in the Potash Area, so the salt section is
not protected to the extent it is in the Potash Area. A salt string of casing is not usually
required and cement normally ties back to the base of the salt section. Plugging
operations in the Potash Area now require a cement plug over the salt section. In the
remainder of the oil and gas producing area in southeast New Mexico, a cement plug is
required at the top and bottom of the salt section. In wells drilled prior to around 1945,
there were no cement plugs required at the salt section.
In every area where flows were encountered around enhanced oil recovery
projects, studies indicated poorly plugged and abandoned wells, deeper wells where the
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