Round 2 - Questions for Enbridge

DurhamCLEAR Followup Information Requests (IR) for Enbridge

July 8, 2013

Reference: A316R3 (these numbers are file numbers for the National Energy Board (NEB)) if interested the entire documentary file including all intervenors can be found HERE.

Response to DurhamCLEAR IR no. 1  - (the numbering below refers to the numbers of the previous set of questions and Enbridge's answers)

2(a)  Given that Enbridge is already paying $600,000.00+ in taxes to local municipalities in Durham Region and given that this will not change if the current proposal is granted,

i) why would it not be more appropriate to pay the municipalities in the Region of Durham a tax based on the volume of the flow?

ii) Please delineate how much is paid to each municipality in the Region of Durham.

iii) What is the highest tax Enbridge pays/will be paying for their pipeline network to any municipal jurisdiction in Canada?

4(a)  The rivers noted in your answer are all ‘navigable waters’.

i)                    Please provide your rationale for limiting such valve placements to these locations?

ii)                  Please provide your justification for ignoring the following comment from the NEB

on page 43 of the 1975 decision by the NEB to permit Interprovincial Pipelines to build Line 9, it states "Navigational use of the river as the basis for the identification of "major" river crossings is not necessarily consistent with environmental aspects. The Board feels that what is important is that relevant environmental considerations be taken into account in locating and designing river crossings regardless of whether such crossings should be designated as major or minor from any particular viewpoint."

4(b)(i)  In your response to this question, you indicate that you do not have maximum flow rates for the streams listed in 4.  However, further on in your response, you indicate that you will use flow rates as part of your emergency response procedures.

Please advise as to the following with respect to flow rates: 

(a)        You indicated that you do not have maximum flow rate data, do you have other flow rate data.  If so, please provide.

(b)        If you do not possession flow rate data, will you take measurements of the flow rates at the time of arrival at the release site?

(c)        Do you have some other method of measuring flow rates on the spot?

(d)       Do you have access to flow rate data or connection to another agency that will provide you with this information in a timely manner? Who would provide such information?

4(b)(iii) Enbridge failed to respond to this information request.

a) Is this omission an acknowledgement that Enbridge does not have this information?

4(e)  Please advise how the figure 14,560 bbls (2,315 m³) for the ‘worst case release’ relates to the figures at page 8 of the Revised Risk Assessment (A316Z1) which states a potential loss of 95.2m3.

i)              Is the 14,560 a static flow due to gravity after the valves are closed? If so, which section would drain that amount?

ii)            Is the 95.2m3 a dynamic flow under pressure before the valves are closed?

iii)          Would the 2 amounts not be additive?

5(a)  Can you advise as to what the highest psi is that Line 9B has operated at and for how long.

5(j) You indicated that Enbridge does not use elbows in its pipelines. 

i)              Can you please advise how Enbridge accommodates hills, valleys, bends and curves in its pipelines?

ii)            If these are accommodated through bending an otherwise straight pipe, what are the implications of the compression and extension forces on the inside and outside radii?

iii)          What is the radius of the tightest bend in Line 9B in the Durham Region?

iv)          Since watercourse crossings are meant to have double thickness walls (1/2”), what procedures or modifications are made to accommodate the obvious need for bends in watercourse valleys? 

5(k) You stated in your response that, during the annual cathodic protection survey, “performance is evaluated by obtaining sacrificial anode currents where accessible.”  

i) What situation would lead to the non-accessibility? How does Enbridge determine the status of the anode when its current is non-accessible?

6(a) Pipeline monitoring

Reference: NEB IR 3.10.c 

“Visual surveillance and reports – Enbridge conducts aerial and ground line patrols of its pipelines. In addition, it manages third-party reports of oil or oil odours through its emergency telephone line, and communicates with affected publics and local emergency officials through its public awareness program.”

Given your reply in NEB IR 3.10.c that Computation Pipeline Monitoring systems (CPM) will not detect a leak below “70.5 m (443 bbl) over a 2 hour period”, this question refers to smaller leaks which would be detected visually or from reports.

 i)                    How often are aerial patrols conducted? How many otherwise undetected leaks have been identified in this manner? What percentage of all leaks are detected in this manner? When was the most recent such patrol conducted over the stretch in Durham Region?

ii)                  How often are ground line patrols conducted? How many otherwise undetected leaks have been identified in this manner? What percentage of all leaks are detected in this manner? When was the most recent such patrol conducted over the stretch in Durham Region?

iii)                How many otherwise undetected leaks have been identified through “3rd party reports of oil or oil odours”? What percentage of all leaks are detected in this manner?

Given a typical depth of 3 ft., the soil around a small leak could be saturated with several barrels of oil before it was visually detected, and this oil could be contaminating the groundwater wherever the pipeline lies near or under the water table.

iv)                When you conduct integrity digs, do you ever find otherwise undetected leaks which are slowly leaking into the soil? How many such leaks have occurred on Line 9? What percentage of total leaks are detected in this way?

v)                  If such a leak is detected, what tests do you perform on the ground water? What corrective action would you undertake if you find that the ground water is contaminated?

vi)                How is the contaminated soil treated?

vii)              When leaks are found through aerial patrols, ground line patrols, 3rd party reports or through integrity digs, does Enbridge conduct a forensic analysis to determine why the leak was not detected by any of its other means. If so, what conclusions have you reached? If not, why not?

6(c) Given the wide range of compounds and mixtures listed in your answer to Les Citoyens au Courant 5.17b in response to our question about diluent composition, we note that most of these are quite toxic and many contain carcinogens and mutagens.

i)                    If a rupture were to occur at any particular point in the line would you be able to tell the response workers at the site exactly what they were dealing with?

ii)                  If not immediately, how long would it take to provide them with accurate WHMIS information?

6(k)  In the event of a release, should Enbridge product enter the cooling intake mechanism of either OPG Darlington or Pickering reactors without OPG’s knowledge, what would the impact be on the cooling system and/or the nuclear reactors?


2. Additional Questions

a) A316Z1 – 01  Revised Risk Assessment

Reference:  page 8 of your revised risk assessment yields this table. Is this correct?


Increase in risk from current configuration

240,000 bbls/d


300,000 bbls/d


333,000 bbls/d



i) What would be the decrease in assessed risk if the capacity was reduced by 20,000 bbls/day from the current capacity? – 40,000 bbls/day? Could you create graph showing actual risk numbers rather than percentages

 Reference: graphs on pages 19 & 21 – ‘Fig. D Risk Profile for Line 9B Current Configuration vs Reversed Flow’ & ‘Fig. F  Line 9 Capacity Increase: Risk Results’

ii) Please provide graphs showing the area of Line 9B through Toronto, Durham and Northumberland in greater detail so that the individual 1,000 ft sections can be delineated and mapped. Also provide the likelihood and consequence factors which combine to form the risks for each section under each scenario.

b) Section Replacement in Clarington

We have received information (which was apparently confirmed at the Enbridge Open House at the Whitby Curling Club on June 19) that a section of Line 9 through Clarington (part of Durham Region) was recently rerouted to accommodate the construction of Hwy 407.

i)                    Is this correct?

ii)                  If so please specify the location and length of this realignment and when it was done?

iii)                Was this reconstruction done to the same specifications as the original pipeline?

iv)                Was the piece which was removed examined forensically to compare actual ‘features’ to those which may or may not have been ‘seen’ with ILI? If not, why not?

c) Exposed sections at watercourses

Reference: A316X8 - Enbridge Response to City of Toronto (“Toronto”) Information Request No. 1

In the response to the information requests from the City of Toronto p 34, you acknowledge, in regards to ground cover  

“d.a.1)  Four locations within city of Toronto have had to have corrective action taken:

1. Newtonbrook Creek - KP 3080.01 – Pipe found to be exposed in bottom of creek during slope and stream survey June 2013.

2. Don River - KP 3081.70 Enbridge is planning to replace 700 m of pipe and install the

pipe several meters below the river bed. Work is scheduled to

start August 2013

3. Rouge River - KP 3095.35  The east bank of the river had extensive erosion exposing the Enbridge pipeline. The erosion has been repaired by installation of a live crib - work was complete in 2011.”

(Note: I have been informed by the person who first reported the exposed pipe at the Rouge River that it was reported in July of 2012 and the repair was completed in late 2012.) 

Given that these three instances are all of recent discovery & correction, Line 9 would appear to have a problem with erosion at rivers and streams.

i) When last were the multitude of rivers, streams and creeks in Durham Region surveyed for erosion? What was found?

d) Wall thicknesses under watercourses

Reference: "NEB Report to the Governor in Council OH-1-74" (Original approval of Line 9)

p.27 “With respect to river crossings, the Applicant mentioned that the wall thickness of all pipe  under watercourses flowing into the Great Lakes and the St. Lawrence Seaway would be increased to 0.500 inches.”

i) Please indicate which watercourse crossings in Durham have increased wall thicknesses?

ii) How many metres on either side of these watercourses does this increased wall thickness extend?