Ref.: TEP DK 15-066 To : Jette Brønnum (Frederikshavn Municipality

Ref.: TEP DK 15-066
To : Jette Brønnum (Frederikshavn
Municipality)
From : Rachel Keown (HSE Coordinator, TEP
DK)
Copy : Nathalie Limet; Henrik Nicolaisen;
Pablo Tallone, Aurelien Joathon (TEP DK)
Date : Tuesday 16th June 2015
Object : Variation 1 to Fixed-term license for the discharge of wastewater collected via suction to
Sæby or Frederikshavn Waste Water Treatment Plant (WWTP) (granted 4th May 2015) (Vendsyssel1)
Subject
1.
BACKGROUND
th
Frederikshaven Municipality, on 4 May 2015 granted a Fixed-term license for the discharge of wastewater collected via suction
to Sæby or Frederikshavn Waste Water Treatment Plant (WWTP) from the drill site in connection with exploration drilling
Vendsyssel- 1 for shale gas by Dybvad.
nd
As discussed with the Municipality in the meeting of the 2
2.
June 2015, TEP DK requests a variation to the existing license.
WASTE WATER
2.1 SOURCES
The waste water that is sent offsite to either Sæby or Frederikshavn Waste Water Treatment Plant (WWTP) comes from the
following sources:
•
Inner area drainage & dewatering water,
•
Outer area drainage water.
Detailed descriptions of the inner and outer drainage arrangements have been provided as part of the original licence and are
not repeated in this variation request. Within the inner area, part of the waste water is generated from the dewatering process,
which involves the separation of the aqueous phase of the mud from the solids. The waste water from the inner area is removed
directly through a hose to a vacuum truck. Water is removed directly from the outer area through a hose to a vacuum truck. All
waste water is analyzed prior to dispatch.
TEP DK still wishes to keep the possibility of utilizing the discharge to the Ovnstrup Bæk. Which is an approved discharge of
under the license dated 15th January 2015, permitting the discharge of surface water from the drilling-site associated with shale
gas exploration well Vendsyssel-1 at Dybvad to Ovnstrup Bæk.
A condition of the original license was that the drilling mud composition is that which is outlined in the original VVM report
prepared in 2014 (TEP DK, 2014a). Since then there have been additional additives added to the drilling fluid mud program.
These are:
•
NOBUG (biocide)
•
SAFE-SCAV NA (corrosion inhibitor)
•
NULLFOAM (defoamer)
•
POTASSIUM CHLORIDE (shale inhibitor)
•
Nut Shell (lost circulation)
•
Mica (lost circulation)
•
Form A plug II (lost circulation)
•
Lime (pH control)
•
Ironite Sponge (H2S scavanger)
•
DF-550 (Defoamer)
•
MB-5111 (Biocide)
The additions of these drilling additive products are not expected to change the components of the waste water, waste handling
arrangements or treatment of waste water. The Municipality is aware the addition of these products has been assessed as not
requiring an environmental impact assessment (VVM) as determined by the environmental authority.
2.2 VOLUMES
TEP DK requests an increase in the daily volume permitted in Condition 10 of the license. An increase is requested to
accommodate all sources of waste water stated in Section 2.1 above. The table below provides an estimated volume of
dewatering water generated per day.
3
Water source
Estimated volume of waste water generated (m /day)
Waste water generated from the dewatering process.
30
Table 1: Estimated volume of dewatering generated per day
3
The current permitted volume discharged/dispatched under the license is 150m /day. This accommodates the inner area
drainage waters and has been determined based on the entire volume of rainwater reservoir, excluding the buffer volume being
emptied in a day.
3
Assuming the same principles, a volume of 200m /day would be required for the outer area drainage (as the volume of the basin
3
3
3
is 385m comprised of 200m rainwater reservoir plus 185m buffer).
As this license variation is being requested to include all sources of waste water, TEP DK requests a revised discharge limit of
3
380m /day.
3.
REFERENCES
TEP DK, 2014a. Exploration Well Vendsyssel – 1 Environmental Baseline Study. TEP DK. Ramboll. March 2014.