ERCB & Alberta Environment Waste Management Regulations

Sites that are used to bury cement returns or to store, mix-bury-cover, land spread, or biodegrade drilling wastes are physically disturbed and hence, are required to be reclaimed. To date, limited reclamation certification applications have been processed for sites on which these types of activities have occurred. Disclosure of unreclaimed sites is required.

Licensees must disclose the following by Month xx 2011 (one year from date of publication):

    1) any remote site that has a sump that contains drilling waste and for which the storage duration has exceeded either one year of the rig release date of the well that last contributed drilling waste to the sump or 18 months of the rig release date of the first well that contributed drilling waste to the sump;

    2) any remote site that has been in use for more than five years as a remote sump/storage site (e.g., multiple sump/storage systems over the years);

    3) any remote site that has been used to biodegrade drilling waste for more than five years; and

    4) any remote site used for disposal of cement returns where large volumes were buried or placed into a pit or pits and where the collective dimensions of the buried cement returns/pits exceed an area of 100 m2 (i.e., about 10 m x 10 m). Disclosure of a remote site is not required if an approval for its extended use has been obtained from the ERCB or if the site is in the final stages of reclamation or has been reclaimed, as in the following situations:

A well site requires a written agreement from the landowner or from the department/agency managing the land of behalf of the provincial or federal Crown (e.g., a surface lease, a right of entry agreement, or a disposition under the Public Lands Act). Whereas additional landowner/department/agency consent is not required to manage drilling waste on the well site on which it was generated, consent is required:

Sumps must only be constructed on sites with appropriate deposits of clayey soils that are free of hydraulic defects, such as sand lenses, cracks, or fissures. Licensees must meet the following sump construction requirements:

    4) Licensees must have a qualified person conduct a site investigation to delineate the in situ clayey deposits. The site investigation must consist of the following:

        a) A minimum of three boreholes, arranged in an approximate equilateral triangle, to establish the orientation of any significant geological plane. Sufficient lithology data (borehole) must also be gathered to confirm that the deposit of appropriate clayey material extends a minimum of 1 m beyond the horizontal and vertical dimensions of the sump.

        b) A representative clayey soil sample from at least three boreholes (refer to point 4(a) above) must be individually analyzed in a lab to confirm that the clay deposit has the following characteristics:

             i. greater than 50 per cent fines (defined as dry weight percentage passing the No. 200 sieve)

            ii. greater than 20 per cent clay i.e., (0.002 millimetre [mm] or smaller as determined by the hydrometer method)

            iii. a Liquid Limit (LL) equal to or greater than 30 per cent

            iv. a Plasticity Index (PI) equal to or greater than 10 per cent

        c) For sumps of an area of 100 m2 or less (roughly 10 m x 10 m or less), the lab analysis required in (b) above can be reduced to one sample provided the three cores from the boreholes required in (a) above are similar in texture (i.e., hand texture method) and appearance, indicating limited variability for the characteristics set out in (b) above. Note that the reduction of lab analysis described in point (c) above does not apply to sites with more than one sump.

    5) Before constructing the sump, licensees must prepare the site following typical well site and soil conservation practices. During sump construction it is important to determine whether naturally saline subsoils are being excavated. In situations where this occurs, care must be taken to appropriately stockpile these soils and replace them at an appropriate depth so that at the time of final reclamation the site can be restored to equivalent land capability.

    6) Licensees must maintain a minimum freeboard of 0.5 m on sumps at all times. Annual precipitation rates, in addition to the volume of the expected drilling waste, must be considered when determining sump capacity.

    7) Licensees must construct the sump such that it will not collect natural surface water (e.g., by site contouring or berms) and will not allow migration of contaminants beyond the walls and bottom of the sump.

    8) Licensees must only place drilling waste in sumps. It is prohibited to mix camp sewage or other oilfield wastes (e.g., produced fluids, completion fluids, work-over fluids, or spill material) with the drilling waste. Precipitation landing within the sump must be managed as drilling waste.

    9) Licensees must isolate rig wash from the drilling waste when hydrocarbon/mineral-oil based drilling fluids are being used (i.e., not placed in the sump) and appropriately manage it.

    10) Licensees must locate sumps such that the exterior walls of the sump are at least 20 m from any on-site rig water well, 100 m from any off-site water well, and 100 m from a water body. The water body separation distance can be reduced to 50 m if the water body is upgradient of the sump or if the landscape creates a physical barrier that would prevent migration of drilling waste towards the water body.

    11) Licensees must secure the sump so that it is not a public hazard; e.g., implement fencing or other measures to prevent public or animals from entering it.

    12) Licensees must not construct or use sumps on sites that do not have appropriate clayey soils. Other storage systems include

        a) aboveground tanks or other storage vessels,

        b) sumps lined with a synthetic liner, or

        c) alternative storage systems approved by the ERCB.

    19) Licensees wishing to reuse a sump/alternative storage system for another drilling program must verify its integrity prior to reuse (earthen-bermed storage systems must not be reused).

In some situations, cement returns are not isolated from the drilling waste and get placed in

the sump and are managed with the solids using the mix-bury-cover method. This practice is

acceptable provided all of the requirements for mix-bury-cover are met.

    23) Licensees must use one of the following options to manage cement returns that have been isolated from the drilling waste:

        a) allow the isolated cement returns to harden (e.g., in structures such as cement rings), and transfer to an approved landfill for disposal;

        b) place the isolated cement returns into a segregated pit (or pits) on the originating well site or associated remote sump site, allow the cement to harden, break the cement into pieces 0.5 m3 or less in size, and cover the pieces with at least 1 m of clean fill.

In addition,

            i. landowner consent must be obtained before placing cement returns into the pit(s) in situations where one pit or the collective area of the pits exceed 4 m2;

            ii. the pit(s) must not be constructed in the water table;

            iii. the area of one pit, or collective area of the pits, must not exceed 100 m2 (i.e., about 10 m by 10 m);

            iv. measures must be implemented to prevent the public or animals from entering the pit(s);

            v. the buried cement returns must not interfere with subsurface water flow and the objective to restore the site to equivalent land capability; and

            vi. the buried cement returns must be disclosed during the reclamation process for the well site or remote sump site.

    d) apply to the ERCB for approval to manage or recycle the cement returns in an alternative manner (see Section 18).

ERCB Full Documents