AER: CSS Operations are fine

CSS Restrictions won't apply here

bitumen emulsion to surfaceToday the AER published a report on their investigation into the flow to surface problems at CNRL Primrose. Primrose had five reported locations where bitumen emulsion flowed to surface. The flows were not restricted to old wellbores but also seeped through poor cap rock seal due to natural and induced fractures. Mostly the AER blames salt dissolution under the bitumen formation for weakening upper strata.

In their briefing to the media today, the AER said that CNR had been operating within their approval limits and the company has not been charged. However, injection restrictions were placed on some areas of Primrose. These restrictions include restricting some areas to low pressure CSS. But the regulator has further restricted areas within a kilometer of the flow to surface events to very low pressure hydrostatic pressure steam flooding.

The AER confirmed that restrictions in Primrose do not affect other operations by the CNR or by any other operator. That means this CSS project by another operator is fine. Nevertheless, the mindset of the regulator has certainly been altered by these incidents. For example, there are new regulations requiring review of abandoned well integrity within ER Schemes.

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Tags: Thermal, Heavy Oil

Granger Low  21 Mar 2016



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