(A)   In reply to the following comment: 

“On the matter of non-biogenic sources of methane and sudden inflow events and significant recharge of methane”: 

There is no credibly proven scenario for a non-biogenic inflow of methane into the lake. Fossil methane is speculated to have formed in the Graben underlying lake Kivu. The proximity of hot volcanic zones under the northern end of the lake may compromise the potential of such a source of methane to exist for the long term. Also, fossil methane would almost always include ethane/propane/butane in the mix. These are not present in the any of the gas recovered. That’s a marker for biogenic gas.

Biogenic production remains a more plausible explanation for “sudden inflow” in geological time terms. But this applies only in a scenario where doubling the resource may take say ~100 years instead of 200.  It won’t be instantaneous as that would trigger an eruption.

On the matter of recharge: A better statement would be that Schmid’s results, using not-fully-proven measurment techniques in the deep lake conditions, can neither confirm nor reject a significant recharge. What other credible source of methane exists?

If this wholesale re-theorizing of gas origin is proposed as a conclusion, it is very far-reaching. It would therefore be extremely important to properly verify and peer review. What, for example, is the alternate hypothesis on the origin of the methane? Where did the missing methane go between two sets of data? It is trapped and cannot go anywhere if not extracted or erupted. The measurement method may be subject to significant error. What calibration method was used. For example, if the error is -20%, the opposite conclusion would have to be drawn. 

The findings, (not a conclusion) given by Schmid raises questions and does not establish an incontrovertible conclusion yet. The techniques used were not yet convincingly calibrated for this purpose. Nor were they for the mix of constituents or for the depth of resource. We can suggest that the measurement tool may be promising as a method and deserves consideration. But any gain in the lake methane content, or even unexplained reduction as may be proposed here, is dependent on other factors not mentioned here. 

For example:

• The range of results in the Boehrer paper shows methane figures such as 18.0 +/- 1.0 mmol/l. at depth. That variability is +/- 5.5%. What is the comparable variance with other methods?
• Is there a comparable commentary on the accuracy/variance of numbers back in 1975 and 2003/4? Could we have a combined variance of between 10-15% from then to now? If so, are any of the conclusions that can be drawn falling outside the potential error range? Therefore, are they statistically significant, or not? This is not explained.

(B)   The panel report states that: 

“The conclusion of this research is that the risk of a gas blow-out is not increasing, and additionally that also the lake’s methane resource is not renewable i.e. equivalent to a fossil fuel source.”  

If this is a conclusion, what is the alternate hypothesis on the origin of the methane? See response above. The measurement method may be subject to significant error. If the error is -20%, the opposite conclusion could be true. This is by no means conclusive or acceptable yet. Years more data are needed to provide proof for such slow change. The measurement error range is equivalent of 10-20 years of earlier assessments of rate of change.

(A)   The panel report further states that: 

“At some depth gases released from the riser flow are captured in a separator being a container at some specific depth (read hydrostatic pressure) were dissolved and free gases are in equilibrium.”  

This statement is neither good, nor syntactically correct, nor scientifically correct, nor valid in any engineering sense. Gas release is not instant and therefore not in equilibrium in separators. Static systems over a long time reach equilibrium, but dynamic systems do not over a short time. That’s false.

(B)   The panel report states in this same section: 

“The natural ratio of methane to carbon dioxide in Lake Kivu appears to be too low to run biogas engines.”  
Appears? It is, at 20% methane, too low by a large margin. You can use that 20% methane mix to put a fire out instead. 50% is close to the minimum combustible methane in gas for engines.

(C)  A further panel comment is 

“The less-favoured alternative by the expert group was the Density Gradient Draw-Down Method (GDM) though this method does appear as plan B in the MPs, see below.”  
In response, this “GDM” was not just “less-favoured”, but absolutely and comprehensively rejected by all other experts in the group. The GDM (which is NOT the same as Plan B) has a destructive impact on the natural stability structure of the lake. It also brings vast quantities of nutrients from deep water into shallow water. A principal reason for its rejection was the long-term instability of the lake. It comes from existing and (if and when new gas generation produced) fresh gas, that it would no longer be contained in the lower half of the lake. The same applies to all gas remaining after the first 50-year harvest.

(D) Comment:

  The MPs are not clear whether this is per concession or per production unit and what should be the geographical dispersion of the production platforms.
Plan A1 requires smaller production units to reduce the impact of large volume extraction and re-injection flows on the gradient layers. A limit of 5 MWe in the output capacity was agreed at the 2008 and 2009 conferences of the experts. It was not an absolute figure but the best guidance at the time. The sensitivity of the gradient layers (260 m and 310 m) to large volumetric flows was the major concern. This is one of many contraventions by KivuWatt in its design.

(E) A further panel comment is 

“The less-favoured alternative by the expert group was the Density Gradient Draw-Down Method (GDM) though this method does appear as plan B in the MPs, see below.”
Tietze lobbied for this alternative on the grounds that he could “invent” a method of extracting all nutrients within the riser pipes. He proposed that this could be part of the process of releasing the gas from the deep water. Tietze could not offer any clue as to how this nutrient extraction idea could be achieved. He has not managed to do so in the ten years since. Therefore, to raise the GDM as a viable option is both dangerous and retrogressive science.

In the end Plan B turned out to be impossible to implement, as the required drop in density could not be achieved, without dilution causing the consequent “loss-of-use” of much of the gas in the URZ. Plan B should be disregarded as a viable option, as noted in the comment above, and deleted from the MPs.

(F) A footnote in the panel report says: 

“The MPs are not clear whether this is per concession or per production unit and what should be the geographical dispersion of the production platforms.”
The MPs do not imply that 5 MWe is a limit on the size of a single production platform, nor for the capacity a concession. That is a mis-read. What it suggests is that a number of 5 MWe modules could be attached to a single barge/platform. i.e. Five such modules could produce 25 MWe and ten could produce 50 MWe. This is simple arithmetic, in case anyone missed the point. However, the spacing between individual 5 MWe production modules still had to be at least 100 m.

KivuWatt has placed four larger modules (80% over-sized) within 50 m of each other in their design. 50 m is too close and will cause short-circuiting. The only way this would have worked for them was to re-inject their degassed water into the PRZ, where consequences are damage to the critical density gradient. It was ultimately a poor solution, perhaps their “least worst” available, but a destructive one at that.

What were the concerns of the Expert Working Group about short-circuiting?

(A) Comment: 

Hence, dilution of the URZ without energy production should be avoided to exploit this resource in the future. Yet, the gas pressures in the URZ are nearest to saturation limits, see Figure 2.4, though still at a safe level.
This may have been KivuWatt’s (mis)interpretation of the MTRs. The requirement clearly states that it should use the URZ first, as the zone more sensitive to poor re-injection practice. Symbion had a worse interpretation They assumed that they can re-inject degassed water to the URZ.

This litany of bad design practice may have included extraction modules being too large (>5MWe, KivuWatt & Symbion). Some were too close together (KivuWatt, Symbion), or unable to create a re-injection density sufficiently lower than that of the URZ (KivuWatt, Symbion, KP1). The depth had to be greater than at the centre of the 260 m Main Gradient. The required density must be achieved by having the uppermost separator between 10-12 m below the lake’s surface. This requirement was not complied with by either KivuWatt or Symbion in their designs, with their top (only) separator at about 20-26 m below surface.
At first here may have been slight inaccuracies in the Chen-Millero re-injection density calculator provided by EAWAG. But any error was not nearly as gross as the 20+ m separator depth selection made by KivuWatt and Symbion (or perhaps Axxxxxx who carried out their engineering). 

(B) Review Panel Comment: 

“The MPs do not specify the consequences of short-circuiting; we infer short-circuiting reduces (i) the methane concentration at the intake level as well as (ii) the upward flow in the risers because the gas lift is less powerful, reducing the upward methane flux even further.”
Short circuiting results in the problem described in detail in Michel Halbwachs’ paper, quoted in his paper. The consequences are progressive dilution of the resource zone and premature failure of degassing. This problem was clearly identified in the development of the MPs. So was the need to position the top-most separator at a level that prevents mixing and hence this form of dilution.

So, of course short-circuiting would do that. Some things are obvious enough that the MPs do no need to spell them out in great detail. Short-circuiting from a poorly executed design was a warning in the guidance section of the MPs. It was only inserted as a rule to the extent that water had to re-stratify above the resource water through density difference. One should expect designers to have some logical capacity in their thinking. 

Similarly, one expects that Halbwachs would understand that one has to separate re-injectate from the resource water. The separation works by re-injecting above the resource water at a density difference, as stated. The new lens of lighter water can remain separate if the density difference is large enough and the water is calm enough. This is why it is written up so in the MPs. The overriding need was not to place the re-injectate above the Main Gradient, due to much more serious consequences like destroying the Main Gradient. There was therefore no need to calculate the consequences of getting this wrong, writing a paper on the subject and blaming the MPs for making a mistake that it clearly warned against.

(C) Review Panel Comment on p19: 

“The intake and the discharge in the same 40-50m thick depth range of the URZ may cause short-circuiting”

To repeat the above point: It may cause short circuiting if the density of the reinjection is not reduced sufficiently to create a sub-layer above the URZ. The control mechanism for density control is the depth of the uppermost (or single) separator used. KP1 has a single separator, which is too deep to achieve the required density by CO2 removal.

(D) Comment: 

Given the suggested 20 years lifetime of Plan A1/A2 this example would involve 34-35 platforms with anchoring, risers, and pipelines distributed over Lake Kivu. This number of plants may be too extensive for commercial exploitation and investments and required spatial distribution over the lake (see also chapter 7 on concessions).

The question is built on a simplistic and incorrect assumption and interpretation of the plan. Clusters of “5MWe” modules can be spaced out around a single platform. This solution is neither too extensive nor too expensive as implied. As described several comments above, it is a simple engineering decision. i.e. Use multiple, adequately distanced modules around each platform.

KivuWatt and Symbion both used multiple modules, but grouping them too close to achieve the needed effect of minimising negative impact on gradient layers. There are better designs available to fit the requirement, most likely even cheaper than KivuWatt’s design. They include appropriate anchoring for the modules.

It is a simple engineering decision to use multiple, dispersed modules around a platform. There are designs available to fit this spacing requirement. 

(E) Comment on p19: 

“No context is presented for allowing to change from Plan A1/A2 to Plan B.”
Plan A1/A2 were conceived at a time that the detailed density calculations to support their operation were uncertain. That density calculation by Chen-Millero was confirmed subsequently. The engineering needs to achieve the combination of A1 and A2 were confirmed.

Plan B was inserted as an alternate, potentially simpler plan to be tried treat the URZ and LRZ as a single zone. It required drawing resource water from the bottom of the LRZ and re-injecting degassed water above the top of the URZ, but below the centre-line of the Main Gradient. It proved unnecessary. Furthermore, the calculator proved that Plan B was much more difficult to design for, as it required the top separator to work under partial vacuum. No transition to Plan B is needed. It does not address Lake Kivu’s Dangers.

To continue from the above point: Plan B is problematic to operate and expensive to design, build and operate. We foresaw it as a standby option, but it proved to be of no value. One can demonstrate this in an engineering calculation, performed using the Chen-Millero calculator. It shows that the separator needs to have negative pressure to achieve the required density and restratification.

In the panel review document, Plan B is several times referred to being the same as KivuWatt’s design or Wuest’s PR1 concept. Neither is true because they both discharge degassed LRZ water into the PRZ. These options are highly damaging to the Main Gradient and must be banned.

(F) Comment on p19: 

“Subsequently, the MPs propose Plan B (Figure 2.8) in which riser water is taken from the LRZ but allowed to be re-injected in the now methane-poor URZ. The MPs define the latter circulation as Gradient Draw-Down Method (GDM) of the URZ-LRZ density gradient or interface, originally at 310m depth. Obviously, Plan B ends if short-circuiting occurs when the URZ-LRZ density gradient sinks below the riser inlet depth and methane concentrations drop to methane-poor URZ level, still leaving some deep volume of methane rich water not easily exploitable.”
There seems to be added confusion in the panel review on Plan B’s intent. Plan B was introduced to harvest the combined URZ and LRZ as one. This followed if there was to be a failure to harvest the zones independently by A1/A2. It is not the same as Tietze’s Gradient Drawdown Method, which is banned in the MPs. Although the intent of Plan B is repeated in the statement above, it gets mis-read and incorrectly confused with the GDM Method.

If one works with the Chen-Millero model, it can calculate the level of a separator vessel required to achieve a desired density. From a desired depth of water extraction, one can work out the installation depth. If the depth is “above” the lake surface, i.e. it needs to operate in a partial vacuum, one can see how Plan B becomes very difficult and expensive to implement. KivuWatt sought an easy way out and re-injected the water back into the PRZ. 

This reinjection plan has turned out to be disastrous for the Main Gradient. The gradient is in the process of being weakened and ultimately will be destroyed by KivuWatt. This is why all the experts warned against KivuWatt’s plan and rejected the ESIA in July 2010.

Is there a clear confirmation that the increase in exploitable methane mass in Lake Kivu is not discernible within the next 50 years?

The papers and data sets from Boehrer (2018) and Schmid 2019 are not yet nearly sufficient to throw out all others. Their measurement method used lacks well-proven validity over the depth range assessed as it was never previously calibrated for the depth or concentration of gas.
Their method will require repeated surveys over multi-year intervals in order to establish and validate either that there is a trend, or lack of any trend.
Further cross-referencing is important in order to establish Schmid’s hypothesis and claims of no-growth or even reversal in the resource in situ.
Uncertain measurement, including ~6% plus/minus data range uncertainty, along with any of a number of equipment failures in other measurement methods used from 1937 to 2004, could result in similar variances. i.e under-reporting or over-reporting is possible in any of the data series.
Similar measurement and calibration problems, including failure to account for sample leakage and temperature change, may well have compromised other tests. It is therefore way to soon to make or justify the conclusions put forward by Schmid, which have far-reaching consequences if correct.
Further, if accepted, the data suggest that methane is disappearing from the deeper resource zones. It was up to now common cause that the Main Gradient act as an impenetrable barrier to gas diffusion from below to above the gradient. 

Disappearing Methane

Only gas extraction or some form of organic consumption of methane could show otherwise. Neither seems likely nor is either proposed to account for a disappearance of methane. One or more set of measurements must be in error for such a thesis to stand, and Schmid is curiously selective on which data he proposes to ignore.
There are several scientific issues to consider, but the key references are:
• Every report on the gas concentration surveys from 1937 to 2019, which references are appended to the panel report and the MPs (up to 2004)
• The 1st Law of Thermodynamics (i.e. Matter can neither be created nor destroyed).

This finding of Schmid would effectively throw out all work done on Lake Kivu in the past with all parties having to reset 83 years of past scientific work and measurement, his included. The physics, chemistry, microbiology, limnology, hydrology, geochemistry and other papers on gas extraction written on the subject would need to be withdrawn or re-written to support his hypothesis.

The MPs would need to be re-written to account for a static or declining methane load, and perhaps the carbon dioxide inventory too. The gas extraction methods actually still need to be the same to preserve the lake safety.
Or, we could check the measurements, past and present, for errors.

How was the development of anchorage of KW barge?

If one evaluates the litany of engineering errors by developers to date, they add to Lake Kivu’s Dangers, including:
• In 2006 the first methane extraction pilot plant REC experienced a riser breakage and sank (not correct, it was unseaworthy and sank)
• Then in 2008 the second methane extraction pilot plant REC experienced a structural/stress failure from poor design and was sinking. It was then ordered to be removed by the authorities before it broke up and sank.
• KP1 experienced gas leakage, failing monitoring instruments and a main-riser that broke off, shutting down the plant for years.
• KivuWatt experienced problems with gas being over-saturated in re-injected wash-water, causing gas bubbling to the surface around the barge.
• The KivuWatt barge’s anchors began do drift in soft, spongy bottom strata, not allowed for in the anchor design, causing the barge to drift in high wind and current conditions.
• KivuWatt failing to design according to the MTRs 3 & 4, among others, causing problems with the stability and longevity of the Main Gradient layer.
Therefore, one can see a persistent trend of bad engineering. Whether it was through incompetence or lack of know-how, it was compounded by the impact of refusing to submit to (or a lack of imposing) the oversight of designs by competent experts. These requirements are set out in the 2009 MPs in great detail thus:

“MAR1: Before applying for permission to proceed with the construction of gas extraction facilities, concessionaires must be able to thoroughly demonstrate that: 

a) their plant designs and operational procedures will be in compliance with the provisions of this document; and 

b) their Environmental Impact Assessments take these provisions into consideration. 

Should existing facilities become non-compliant with an updated version of this document, the Bilateral Regulatory Authority will notify the operator of the non-compliance and the two parties will negotiate a mutually-agreed plan for bringing the facility into compliance.

MAR2: 

The locations of water intake and re-injection equipment will be approved by the Bilateral Regulatory Authority based on their depth, horizontal separation, and flow volumes.

MAR3: 

Prior to construction, design drawings must be submitted to the Bilateral Regulatory Authority for approval. This information will be kept confidential. Submitted designs must include at least all configurations of: underwater pipes, pumping systems, separators, gas lines, gas treatment facilities, gas buffer storage tanks, water mixing systems, compressors and blowers; power supply systems on off-shore barges; and gas flaring systems. All submerged materials of construction for underwater pipes and anchoring systems must be part of the documentation submitted.
a) their plant designs and operational procedures will be in compliance with the provisions of this document; and
b) their Environmental Impact Assessments take these provisions into consideration.
Should existing facilities become non-compliant with an updated version of this document, the Bilateral Regulatory Authority will notify the operator of the non-compliance and the two parties will negotiate a mutually-agreed plan for bringing the facility into compliance.
MAR2: The locations of water intake and re-injection equipment will be approved by the Bilateral Regulatory Authority based on their depth, horizontal separation, and flow volumes.

MAR3: 

Prior to construction, design drawings must be submitted to the Bilateral Regulatory Authority for approval. This information will be kept confidential. Submitted designs must include at least all configurations of: underwater pipes, pumping systems, separators, gas lines, gas treatment facilities, gas buffer storage tanks, water mixing systems, compressors and blowers; power supply systems on off-shore barges; and gas flaring systems. All submerged materials of construction for underwater pipes and anchoring systems must be part of the documentation submitted.
Design drawings must include process flow diagrams (PFDs) and piping and instrumentation diagrams (P&IDs) prepared in accordance with ISO 10628. The design will have been subjected to the HAZOP process, and the HAZOP report must be submitted with the design drawings. This information will be kept confidential. The process flow diagrams (PFDs) shall as a minimum include the basic information as per section 4.2.1 plus items a (mass balance for all gases plus water), b, c, and d from section 4.2.2 of ISO 10628, and the P&IDs shall as a minimum contain the basic information as per section 4.3.1 plus items c, d, e, f and g from section 4.3.2.

MAR4: 

Relevant design data that will be reported at the design stage for all single extraction facilities, and that will be made public, include but are not limited to:
a) depth of all extraction and re-injection pipe openings;
b) design of the extraction and re-injection pipes: diameter, elasticity, heat conductivity, shape of pipe mouth to achieve internal mixing of re-injected water with surrounding water, ejector/diffuser, etc.;
c) design flow rates for all water extracted from or re-injected into the lake;
d) design flow rates including full mass balance, and expressed in SI Units (t/h or normal m3/h or km3/h etc.) for all gas streams produced during the extraction process;
e) the concentrations of methane, carbon dioxide and hydrogen sulphide in said water and gas streams, showing the extraction efficiencies and gas losses;
f) detailed and verifiable calculations of expected re-stratification levels for degassed water and for washing water; and
g) amounts of sellable power and of all internal power consumption in gas extraction.
Any subsequent changes to the above data must be submitted to the Bilateral Regulatory Authority for approval.

MAR5: 

The Bilateral Regulatory Authority has the right of access to gas extraction facilities for inspection at any time, and will provide facility operators with sufficient notice of such inspections. The operator has overall responsibility for safety at the facilities, and thus for granting access. The Bilateral Regulatory Authority personnel will have all necessary safety training as required by the operator for access to the offshore facilities. The operator will provide such training.

MAR6: 

At start-up of a new or modified gas extraction facility, a concessionaire must engage a qualified third party to carry out monitoring in the lake (e.g. salinity and temperature profile measurements) around the point of re-injection. This monitoring will, with sufficient reliability and precision, demonstrate the shape of the plumes of any re-injected water (degassed and washing water).
The purpose is to measure and report, from start-up until sufficient results have been reached, that there are no deviations from re-stratification levels as defined in this document. If necessary, adjustment of density control must take place followed by renewed monitoring until a satisfactory result has been obtained. The third party report will be submitted to the Bilateral Regulatory Authority.

MAR7: 

Operators of gas extraction facilities must report certain operation and monitoring data electronically to, and in a manner and frequency defined by, the Bilateral Regulatory Authority. Operators must be prepared to carry out automatic, online reporting if required by the Bilateral Regulatory Authority.
These data will be made public and used together with other data to develop better scientific understanding of the lake and guidance of extraction concession design, safety and operations.
Operator shall ensure that sample points for all major streams are installed, with suitable valving, for taking the necessary samples and for the Regulator’s appointed third party to take samples on request. Facilities shall be designed to allow carrying out tests with injection of tracers (through sample points).
Data to be reported include the following parameters:
a) Hourly averages of flow rates for all water extracted from and re-injected to the lake, plus the rates of produced gas or electrical power (MW) and cumulative production. Flow meters shall be calibrated once a year and copies of the calibration reports submitted to the Bilateral Regulatory Authority;
b) Monthly average values of flow rates for all gas streams produced by the extraction process, including mass balances showing the methane extraction efficiency and the relative carbon dioxide removal rate; and
c) Monthly average values of water temperature, conductivity and salinity, as well as concentrations of methane and of carbon dioxide, hydrogen sulphide and nitrogen in said water and gas streams, as well as calculated and/or measured densities of the re-injection water.
Other data may be added if concerns for the lake so require.
Once a month, a full set of water parameter analyses shall be made in an agreed laboratory on samples of extracted and re-injected water.

MAR8: 

Concessions should be limited to a time frame considered appropriate by the Bilateral Regulatory Authority. In considering an application for the renewal of a concession, the Bilateral Regulatory Authority should consider, among other things:
a) the overall gas reservoir management plan for the lake;
b) availability of more efficient and sustainable gas extraction methods;
c) the potential need to change the extraction or re-injection depth and/or location; and
d) the potential need to change the carbon dioxide removal rate.
The Bilateral Regulatory Authority has the right to determine what technical renewal conditions will be required.

MAR9: 

A precondition for permission to start operation of any gas extraction facility is that the Bilateral Competent Authority or its representative has been given the opportunity to inspect all underwater piping and their fittings (as well as the materials they are made of) when assembled onshore but prior to installing these under water. “

Our Conclusions?  Frankly, Nothing More Needs to Be Said!
• KivuWatt failed on 9/9 MARs
• So did REC/Halbwachs
• So too did KP1, although it was largely built before the MPs were published.
To correct this problem? Repeat the same requirements (barring Plan B) in any updated version of the MPs, only with a stronger BRA and far harsher penalties for transgressions.

Under what conditions has KivuWatt been licensed?

From the statement on p22 of the panel review: 

“The set-up of KivuWatt is similar to Plan B in the MP, though with re-injection in the Potential Resource Zone (scenario PR1 in (Wüest et al., 2009)). Such a design would not comply with the MP, which calls first for Plan A1/A2 followed by Plan B.”

This statement shows that KivuWatt/Antxxxx did not understand (or chose not to apply) Plan B’s essential requirements. They departed from Plan B by re-injecting into the PRZ. This utterly compromises the intent to protect the Main Gradient. Vaguely similar is not good enough; that’s as close as saying a bus is similar to a chid’s toy car as it has four wheels.

This design element is directly in conflict with one of the more important MTRs in the MPs. KivuWatt is unable to comply with many of the 14 MTRs, including the most important. A KivuWatt-negotiated concession has stripped the GoR of any control over the mis-use of the resource. The lack of a BRA to enforce the MPs (MTRs and MARs) granted KivuWatt a sense of entitlement and immunity to sanction. That adds enormously to Lake Kivu’s dangers.

Concessional requirements have been abused to an extent illustrated by the lawsuit and arbitration case brought by KivuWatt against the GoR for issuing the 2009 MPs. The basis for the suit was “Change in Law”. This is despite the lack of any substantial difference between the Draft 2008 MPs document and the formally issued 2009 MPs on the MTRs and MARs that KivuWatt has flouted.

KivuWatt’s grievances on the above legal issue seem misplaced. They are trying to attach blame to others for what is a growing litany and engineering and design errors and failures.
Scientific background is substantiated by the MPs and the body of work that went into its formation.

Operational Issues

The few known operational issues are largely anecdotal since KivuWatt publishes virtually none of the required data and reportage required under the MARs. For example:
• From the initial design data put forward in 2010 as “design information” to support KivuWatt’s ESIA application and application for MIGA support, the quality of information, its completeness and its accuracy was laughably inadequate. The technical submission consisted of few hand sketches, lacking even the basic engineering notation. These were put forward for review instead of a feasibility study.
• The absence of any design review or compliance review required by the above-copied MARs is a critical non-compliance.
• Their design, placed four large separators and their intake and re-injection pipes within a 50 m linear arrangement below their barge. It was against the guidance of the MPs.
• The report-back to the February 2011 Rubavu stakeholders conference, where the country manager of KivuWatt, reported that KivuWatt and its engineers “simply did not know how to design a degassing and re-injection system for degassed water to comply with the MPs.”
• Reportage of incidents, such as the aborted plant start-up in 2014/15. The resulting cloud of bubbles rising up under the platform from over-saturated wash water, was never reported publicly.
• Their need to re-design and rebuild the gas washing system to correct the above design defect. KivuWatt claimed this as a cost due to “change-of-law”, an absurd claim at best and fraudulent at worst.
• KivuWatt’s need to double-up on anchoring systems due to the failure of the original anchors to perform under the lake’s changeable seasonal wind and current conditions. This shows bad design practice. They blamed “sludgy bottom conditions”.

Weakening the Main Gradient is Huge among Lake Kivu’s Dangers

• Most serious of all is the evidence from LKMP monitoring of the lake-wide weakening of the Main Gradient. Monitoring shows alarming evidence of the impact of degassed water re-injection into the PRZ. This contravention alone should require the immediate shut-down of their GEF.
• The overuse of resource, due to extremely poor process efficiency. Plus, the sole use of the resource volume in the band between 310 and 355 m depth, means that KivuWatt is accessing well below 50% of the available resource but overusing that band beyond its share. Arguably, KivuWatt uses or sequestrates between 3-5 times as much resource as the best available technology for the same net power output.

All the evidence above indicates that the MPs were substantially correct in requiring the technical compliances and administrative compliances. From my review of the MPs, there are many potential additions and one required deletion to the MTRs. The additions are written up in a joint paper written by Hirslund and Morkel, published in Elsevier’s Journal of African Earth Science, January 2020.

Perhaps a proper review would have thus dissuaded KivuWatt from building this GEF at all. Or it would have at least saved itself from so many embarrassingly incompetent design and engineering errors.
The former would have saved both the countries from expensive wastage of resource, not to mention an increase in the danger levels of the lake. The latter would have saved KivuWatt from tens of millions of dollars of wasted expenditure and years of delayed start-up.

Bilateral Authority

As noted in the panel review document, the BRA was a necessary institution that should have been created to police the many infractions committed by Kivuxxxx. This need is even greater now, as the sense that developers can use political-legal mechanisms to flout the MPs seems to have become the “ruling precedent”.

We noted that Symxxxx proceeded in virtually the same manner in engineering and design of their proposed GEF. Most of the same design non-compliances were repeated by their engineers. Antares, also did similar poor work on the KivuWatt design. The design changes incorporated only modestly address deficiencies in Kivuxxxx’s GEF design.

Fortunately, REMA has seen fit to reject the ESIA put forward by Symxxxx/Shema, which has at least one design element that is worse than Kivuxxxx’s, with respect to re-injection.

Panel Review Statement: “Remove the scientific doubts between these conflicting views, record it and publish it.”

From the reported conflict on p22: Hirslund (2012) argues that in Lake Kivu chemoclines (constituent or dissolved-gas levels) or isopycnals (density levels) are moving upward by inflows to the deeper parts of the lake. These come from water sources with different salinities (citation from abstract Hirslund, 2012). From these inflows and consequent forced upward movement, Hirslund argues that local gas saturation increases. Thus there is an increase in the probability of gas eruption. Hirslund therefore proposes mitigating actions to limit the rise of chemoclines.

Schmid and Wüest (2012) object to these mitigations. While they acknowledge that observed thinning of the chemoclines from below is poorly understood, they hold that sub-aquatic sources maintain the chemoclines at their present levels.

Having been at the periphery of both of these arguments, I was part of a discussion on the merits of each. My initial take was that Schmid & Wüest were correct. They argue that the sub-lacustrine inflows would “shave off” tops of any rising chemoclines, keeping their levels constant despite thinning.

Moreover, in arguing this matter with Hirslund in favour of the view of Schmid & Wüest, Hirslund showed that the top fraction of a chemocline may be subject to this dilution/shaving effect, but that the body of the chemocline was not. DDL can explain the same phenomenon.

Inflows Level

He also argued that sub-lacustrine inflows will settle at their own level, determined by the inflow’s density. Measurement from 1975 to 2004 showed that the gradients’ centre-line (or peak density change) was indeed migrating upwards. The impact of the moving centre-line is material over the long term mass balance changes.

However, much of the disagreement hasn’t been debated scientifically, but expressed more on a basis of personal animus and pride of authorship. It comes down to protecting one’s own thesis rather than doing a simple mass-balance to show that sub-lacustrine inflows will push up gradients.

With the combined effects of double diffusive layering, the sharpening the gradients, data also also shows that the peak of the gradient is perceptibly, and justifiably, rising. I now accept Hirslunds version of the mechanism and result, although less convenient than EAWAG’s. It creates lake management problems that will need long-term solutions.

To say that rising chemoclines is a myth and has no impact is wrong. Simple engineering mass balance puts that proposition down. The volume of water under each chemocline is increasing. Operationally, rising chemoclines cause a growing and significant problem later on with extraction of gas. Rising chemoclines accelerate the rising partial pressure of gas where it presently peaks, just under the 260 m and 310 m chemoclines. This rising pressure persists even if, as Schmid 2019 postulates, no new gas is being generated.

Rising chemoclines will gradually, certainly not drastically, impact the Plan A1/A2 creation of new sub-layers in the URZ and PRZ. This is because with scaled-up production, the sub-layers will thicken faster than the rate of rise of the chemoclines.

Water into the Biozone. Is it one of Lake Kivu’s Dangers?

In this context, mechanisms for rejecting degassed water to the Biozone need sober debate. Degassed water injected to the Biozone has multiple undesirable impacts on the Biozone ecology that must be measured against the safety impacts of rising partial pressures of gas at the top margins of the URZ and PRZ. But something will have to give over time and the alternatives need more study.

Extraction mechanisms proposed by Symbion/Shema do nothing to mitigate the problems of rising partial pressures at the present peak. This peak, at ~265-275 m depth, migrates upwards and grows to be more of a concern.

Ironically, KivuWatt’s method does slightly mitigate present rising partial pressure peaks at ~265-275 m depth and the 315-325 m as their mass redistribution to the PRZ slows the rate of rise of these 260 m and 310 m chemoclines. It does, however, still accelerate the rise of the 190m chemocline.

The 2009 MPs do not address the issue of rising chemoclines. Once the data and proven or disproven theories and mechanisms are settled, hopefully before another 5-10 years have passed, the matter can be addressed by qualified hydrologists added to the mix of experts.
MTRs 3 & 4 are affected by the discussion. A question of new MTRs to address the control of the level of key chemoclines must be addressed in concert with MTRs 3 & 4. While the LKMP and other researchers can help with providing more data, it is the wider set of expertise that will be equipped to address mitigation measures.

The matter is not one to be settled by Deltares and LKMP as they lack the requisite capabilities.

What arguments were used to prefer Plan A1/A2?

This is a short question that requires a detailed and wide-ranging answer to many issues, including:
(A) Halbwachs’ studies deserve the following response summary that we share in our evaluation – Reference is made to non-unanimity in the MPs expert group on the optimal extraction of methane.
A 5:1 majority was acceptable in the circumstances, particularly as Tietze did agree several times during detailed debates. He had agreed with our convincing technical arguments, data and models, only to renege days or weeks later. It was a regular pattern he exhibited over three years. In particular, throughout the 2009 finalisation of the MPs, Tietze agreed with the draft until the last day.

The rationale for the Expert Group rejecting the dissent of Tietze was overwhelming. His and Halbwachs’ views were rejected for good, reasoned arguments on the stability breakdown that would eventuate. They both argued for a method that would have destroyed the future stability of the lake by breaking up the important density structure.
A major safety problem reoccurs well after the completion of 50 years of gas harvesting. That is if gas content is regenerated after the initial gas harvest (as argued in this panel review). Their (Halbwachs and Tietze’s) harvest approach would have destroyed the existing density structure, resulting in a mixed layer taking up the entire lake. This results in a single density layer, like Lake Tanganyika.

Halbwachs issued his paper on the eve of the 2011 Gisenyi conference of stakeholders. The Expert Group nominated Morkel and Hirslund, at the request of Rwanda’s Minister of State for Energy – Dr Albert Butare, to prepare a reply to Halbwachs. The response, repeated here in full and unedited, was provided to him on 18 February 2011:

“To all Stakeholders in Lake Kivu Gas Extraction,
Re: Comments by Prof Halbwachs on Management Prescriptions (MPs) and in particular Plan A1, A2 and B Methods.

Dear Colleagues,

As members of the International Expert Group we wish to respond to all parties addressed by the above correspondence, issued to most workshop attendees very shortly before it commenced. As such, we comment on the Halbwachs’ note and its attached YLec report from September 2009. Being addressed as late as it was, to almost all attendees, these were delivered as an “ambush” tactic to gain attention without allowing an opportunity of a timely rebuttal by the experts.
Nevertheless, we are obliged to properly consider the merits or otherwise of any communication on the MP’s, and to provide all those addressed with a sober evaluation and response. Both the Management Prescriptions and the conference have channels in place for the hearing of objections to the contents of the MP’s, neither of which was used by Prof Halbwachs. It is therefore principally to allay any concerns that could have been raised in the minds of other delegates that we reply as below.
The MPs have been conceived as Society’s tool to prevent future cataclysmic eruptions of the lake while extracting the gas. They are the only known tool to prevent this, and this is why the issue of adherence to the MPs is of exceptional importance. The comments by Prof Halbwachs do not qualify as sufficient reason to change this situation, as described below. If we were to follow these ideas of Prof Halbwachs, we would instead increase the certainty of many future eruptions of the lake.

“Pour tous ceux qui s’occupent de l’extraction du gaz du lac Kivu,
Note sur les commentaires par le professeur Halbwachs sur les prescriptions de gestion (les PG) de lac Kivu, et notamment les méthodes Plan A1, A2 et B

Chers collègues,

Comme membres du Groupe international d’experts nous souhaitons répondre à toutes les parties intéressées par la correspondance ci-dessus, délivrée aux participants de l’atelier à Gisenyi juste avant qu’il ne commence. En tant que tel, nous ne commentons que la note du Prof. Halbwachs et sa pièce jointe de Septembre 2009, s’adressant si tard à la totalité des participants de l’atelier, l’intention claire a été d‘attirer l’attention des participants d’un côté et de l’autre de ne pas laisser la possibilité d’un échange et surtout d’une réponse par les experts avant que l’atelier ne commence.
Néanmoins, nous sommes obligés de prendre dûment en compte le bien-fondé ou non de toute communication sur les PG, et à fournir à toutes questions qui ont été adressées, une évaluation et une réponse mesurées. Pour les PG ainsi que pour la conférence des moyens ont été mis en place pour permettre d’adresser les questions et objections sur le contenu des PG, ceux-ci n’ayant malheureusement pas été utilisés par le Professeur Halbwachs. Il nous semble donc absolument nécessaire d’apaiser les inquiétudes qui pourraient naître dans l’esprit des différents délégués et c’est justement dans ce but que nous répondons ci-dessous.
Les PG ont été conçus comme l’outil de la Société servant à prévenir de futures éruptions cataclysmiques du lac lors de l’extraction du gaz. Les PG sont les seuls outils connus pour éviter cela, et c’est pourquoi la question de l’adhésion aux PG est d’une importance capitale. Les commentaires du professeur Halbwachs ne changent en rien cette situation comme décrit ci-dessous. Si par hasard ces idées du Prof. Halbwachs étaient suivies, cela conduirait presque à une certitude de futures éruptions gazeuses du lac.
 

“Background Issues

On the matter of their being included as part of the creation of the MPs, Prof Halbwachs and Dr Klaus Tietze are long-standing members of the Lake Kivu scientific community whose views are well circulated in publications. There are many parallels and commonalities in their viewpoints and opinions and, as such, one of the two was invited to be represented on the formative Expert Group in March 2007.
The broader scientific, consulting engineering, environmental and extractive technology community was similarly to be included in the group to make it properly qualified and representative. In addition, the group’s appointed members bring with them a broad set of additional skills which have markedly benefited the discussion and development of the MP’s. As such the group was properly and reasonably constituted and was not unduly biased in favour of or against any one particular set of opinions.
Further, in succeeding stages of the development of the Management Prescriptions, between October 2007 in Kastanienbaum and May 2009 where the final draft was prepared, open sessions of the experts were held and successive drafts issued for public comment. The opportunity to attend the May 2009 session was not taken up by Prof Halbwachs and comments on the draft MP’s were refused to be submitted on the “misguided” document on the grounds that he “knew better”. In the final issue of the MPs Dr Tietze was given a right to note his concerns over some elements of the MP’s and to reserve the right to prepare further research on his position and revert with proposed changes with justifications. To date none have been received for consideration.
The MP’s were issued as final in June 2009, and presented to the two governments in July 2009. After receiving copies of widely circulated negative comments on the MP’s, the Minister of State for Energy of Rwanda and the Deputy Minister of Hydrocarbons of the DRC both wrote to Prof Halbwachs to warn him against continued vilification of the MP’s and its authors through the press, including the writing of similar e-mails to the broader community. He was advised to deal with such matters through the relevant authorities, as appointed, and not in the public media.

Specific Objections

On the water re-injection method used after degassing, the YLec consultant’s competencies in fluid dynamics referred to are relevant to the argument on the predicted results of the extraction and re-injection piping and methods, but less relevant to the general safety of the lake. The public safety consideration always supersedes the economic priorities of either country, or any developers, in the order of precedence established in the guiding principles.

In the development of the Plan A1, A2 and Plan B as described in the MPs, these more detailed methods were instituted precisely because of the loss of gas recovery potential through dilution of the resource zones. It was well understood that dilution, caused by re-injection water distributing throughout the two mixed resource zones (URZ and LRZ), would render as much as 40-50% of the methane unrecoverable. Much of the research and discussion that preceded inclusion of these detailed extraction methods centred on their practicality and the relative improvement of gas recovery compared to the dilution method.

Hydraulic Evaluation of MP’s

In Copenhagen in both May 2008 and May 2009, two hydraulics specialists were mobilised by COWI to assist with evaluations. Before, during and after these sessions they advised on the 3-D impact of flows deriving from a variety of configurations of re-injection piping and the impact on flow regimes from the design of nozzles. These experts enjoy at least the same reputation as Yves Lecoffre of YLec, more especially in their hydrology experience of large unconfined bodies of water such as lakes rather than in piping systems.

These independent experts were called in to comment on and verify or dispute the opinions of persons in the expert group. Several of the Expert Group members have experience in the hydraulics of water bodies and flows. They had proposed certain configurations designed to vertically segregate the re-injected water from the underlying resource water in each zone. Detailed simulations were performed by these supplementary experts, based on the flow, density, and other data including the configurations of re-injection piping. Their results were used to determine the resultant shapes of plumes and re-injected water lenses in the lake, especially on the ratio of lens spread to thickness.
Where water of the precise density of the lower half of the relevant gradient layer was re-injected through a correct nozzle configuration, the re-injection lens was shown to stratify very widely, with a limited vertical penetration. With the correct parameters and designs, simulations showed lateral transport of 10 km or more being achieved with a vertical lens thickness of no more than a few metres, a ratio of the order of a thousand times. This spreading potential and segregation of the re-injected water is the basis of both Plan A1 and Plan A2 configurations.

Assumptions as Basis of Objections

The fundamental assumptions given to or used by YLec, gives rise to a serious bias in the results of their analysis. There are nine parameters that need to be well understood in a 3-D simulation, of which too few are mentioned in the analysis provided. Some are assumptions are made correctly, some incorrectly to the extent of being misleading, and too many are not even considered:
• The potential influence of the currents, even if for a transient condition, is discussed;
• YLec’s shape, configuration and flow parameters of re-injection nozzles are unlike any considered by the experts, and they do affect the analysis markedly;
• The assumption of re-injection density being the same as the mixed zone average density leads to the worst case result of zone dilution. Instead, this density should be assumed to being lower than the mixed zone, some 10 % lower than the difference between the mixed zone and the centre-line of the gradient above. This density is made possible by removal of the majority of the CO2 content of the resource water;
• Other parameters such as lens shape, the use of diffusers, selective withdrawal designs, flow rate, double-diffusivity effect on vertical and horizontal mixing should also be properly considered.
With the third point above, where the average density of the mixed-zone is assumed by Halbwachs to be the re-injection density, any resultant YLec simulation is not on a comparable basis with the Expert Group’s simulations. This assumption is wrong and designed to produce a misleading result.

Conclusions Drawn

The statement by Prof Halbwachs that his conclusions are final is rejected. The inherent bias, in both assumptions and modelling methodology, renders the work unacceptable as a basis for such conclusions or for recommending a change to the MP’s. Specifically:
The re-injected water can form a distinct lens, even becoming a distinct layer that forms above the mixed zone of the individual URZ or LRZ layers. During the conference, the simple example given of a cocktail that a barman can make with multiple coloured layers shows the alleged “impossibility” to be false. It’s a matter of skill and precision being demonstrated with fluids of very similar density.
That the dilution of a resource zone leads to a reduced extraction plant’s effectiveness is well understood. The extraction plans in the MP’s were drawn up precisely in order to minimise and delay this effect and then to be able to respond to the eventual drop in effectiveness of Plan A1 after some 20 years by switching to Plan B.
Given all the above, Prof Halbwachs’ conclusion that the description of the technology described in the MP’s as being “totally unrealistic” and “impossible to control” is (in itself) misleading, unfounded and without merit.
The issue of operating to Plan A1 and A2 will remain a concern for the designers and operators of gas extraction facilities, but the effort is necessary to maximise their commercial benefit from their respective concessions while preserving the density gradient layers.

Expert Conclusions

The clear, but unstated, inference from the Halbwachs report’s conclusions is that the MP’s should be based on the original legacy extraction method where the entire Resource Zone is displaced into the Intermediate Zone after degassing. This was the extraction method long-supported by Dr Tietze as well. However, this method unavoidably leads to weakening and, after 50 years methane harvesting, to the destruction of the key stability structures that have evolved to protect the lake for the past 1000 years from self-destruction.

A detailed set of quantitative evaluations and simulations of this methodology was analysed by EAWAG in 2007, with comparisons checked against the new proposed alternatives. The simulations of time-based variations to all parameters established the complex and long-term changes to the lake structure, and the dangers and effects of the total mixing of the lake’s zones. These included:
• The total loss after 50 years of protective density gradient layers that are essential to keep the future gas production retained safely, deep in the bottom half of the lake;
• The virtual certainty that after 50 years, the new gas accumulating will lift to just under the Biozone and will eventually result in frequent smaller eruptions of the lake;
• The injection of gas-bearing water of high gas partial pressure just below the Biozone which will, in time, increase the gas eruption risk with saturation levels up to 100%;
• The lifting of high nutrient concentrations to just below the Biozone will lead to significant impact on the biozone, including possible eutrophication. In the worst case this eutrophication leads to a dead lake unable to support sustainable fish life and can lead to seasonal releases of methane and hydrogen sulphide, in addition to carbon dioxide, from the surface as oxygen periodically depletes;
• The danger of the lake becoming a no-go zone for any surface vessels in the future is contemplated due to outbursts of gas originating just below the biozone. Frequent gas releases could lead to the shores of the lake becoming uninhabitable in the long term.
After considerable debate in the Expert Group on the need to consider the long-term after the 50-year harvest window, it was clear that the top two principles (Public Safety and Environmental Protection) would be considerably at risk from then onwards. It is quite obvious too that the social benefit from the lake, the third principle, would also be severely compromised for future generations.
It was therefore a clear and irrefutable decision by the experts that the Zone Mixing approach to lake harvesting had to be rejected completely in favour of the newer lake stability approach. The sacrifice of a small percentage of potential harvest in the medium-term (50 years) is not a high price to pay in the circumstances. These two divergent extraction methods are also completely incompatible so there is no room for accommodating both side-by-side on the lake at greater than experimental scale, as the chosen method relies on the stability and positional integrity of the density gradient layers to operate and perform.
We are not opposed to further hydrological and hydraulic evaluation and testing of the proposed extraction methods in the MP’s, and in fact encourage it. We would however insist on the proper use of both verifiable assumptions and models to ensure that a correct result is obtained.
Yours sincerely,
Dr Finn Hirslund P Eng

Philip Morkel Pr Eng.”

 Comment on our above letter 10 years on:

Our opinion expressed in the above letter remains substantially unaltered since 2011. No response or rebuttal to the above letter was received by the Expert Group. Nor has any arisen since or within the process of this panel review, commenced in 2019. The Halbwachs paper has been unaltered in the intervening years to cater for faulty assumptions made then in 2009.
Consistent with the opinion in the letter above, in response to Halbwachs contentions, no updates or corrected versions of his paper are published, to our knowledge. 

One assumes that correcting flawed assumptions and applying generally acceptable modelling techniques may have deflated the desired impact of the Halbwachs paper.
That said, if after eleven years there has been no apparent advance by Halbwachs on improving the paper. The 2019/2020 re-issue of it to this review panel should equally questioned for validity of assumptions. So too the veracity of the results as a basis to argue against Plan A1/A2.

What arguments were used to prefer Plan A1/A2? (Continued)

(B) Comment on p25: 

“Re-injection in the (same) zone of extracted water creates dilution and should be prohibited, notably for Plan A1.”

This view was known at the time of the 2009 issue and had been discussed. Halbwachs failed to acknowledge that this hypothesis applied only to reinjection of degassed water at the same density of the resource zone (URZ).
But the stated requirement in the MPs was to reinject at density less than the URZ zone’s density. The difference must be sufficient to form a new sub-layer in the “knee” of the density profile. The density difference must be enough to remain separate from the URZ zone.
The detailed proceedings of discussions at the 2008 conference of the Expert Group were not published to provide as a reference. Parties to the conference, include several hydrology experts from COWI, with whom options were discussed. They include respondents to these questions. The collective opinion, after interrogation, was that the idea of re-injection to form a new sub-layer of the URZ or LRZ was accepted. The MPs were written accordingly. Dr Finn Hirslund must still have access to the same experts and can confirm the evaluation.

(C) Comment on p25: 

“A minimum efficiency in first stage separation should be imposed (75-80% is suggested.)” and “A maximum fraction of methane in re-injected water should be imposed (less than 20% is proposed)” and “A risk analysis of the evolution of a gaseous explosion is needed.” And “Thorough hydrodynamic simulations of the consequences of re-injection by an expert company are required (see below)”.

This imposition of these suggestion is not necessary or justifiable as a rule. Experts drafting the MPs were clear in saying that the process of extraction and gas scrubbing is a “black box”. The black box is the domain of the developer. However, all inputs and outputs from the “black box” are regulated, including their depths within the lake. It should stay that way otherwise the potential for innovation and design flexibility are lost.
What if there were ten separation stages? Would one stage have to do 80% of the work? That is silly and it is not the domain of the regulator to specify internal elements of the design. The regulator must, however, be convinced that the design is practical, adequately pilot-tested or full-scale demonstrated to allow it to be permitted.
The origins of these highlighted statements is not known, but they display a poor understanding of chemical engineering process design. The suggestions must be discarded as they make no sense and have no applicability to the broader options of plant design.

(D) Comment on p25: 

“The pie-shaped sub-division of the lake into concessions each having access to the deepest part of Lake Kivu located north-east of Idjwi Island is hardly feasible near the end (in time and depth) of exploitation. For access to the deepest parts gas-pipe lines should cross the lake to Rwandese or DRC shores with access to high-voltage electricity pylons respecting terrain and owners; a single concession should take over at the end.”

The pie-shape was the only way to give each concession access to the deepest water in each country. It is thus able to produce until the end of the concessions’ lifetime with the illustrated arrangement.
Safety and fairness of concession allocations were behind this choice. This alternative presented is unhelpful and barely comprehensible. The author of this suggestion is unknown, but he/she would be better served by withdrawing this statement.
There is no place for these “narrow interest, no context or self-serving” forms of comment or inclusion in the MPs. This is not in the domain of a regulator.
We must assume that a developer hires a competent engineer and that engineer can design to conform with regulated boundary conditions. They must perform engineering according to industry standards and with the necessary HAZOP or HAZID actions at the appropriate time. If any regulation should be applied to GEFs, it is this paragraph’s italicized sentence!
Further, these ideas apply to the type of legacy design which is inherently unable to operate within the bounds of the MPs. So these have no relevance to the discussion.

(E) Halbwachs’ study 

and more items on your p25 from the YLec Consultants paper have been quoted here with questions raised. They question items such as “The exploitable minimum…”, “A diffuser set-up…”, “Short-circuiting…”, “Single available study on gas lift…” etc.

Consistent with the overall opinion in the above letter response, here are some specifics that show the opinions not to useful, applicable, true etc. For example:
This 5 mol methane per m3 limit is highly dependent on the design efficiency of plant alternatives. It’s certainly true of designs for Kivuwatt, KP1 and probably Halbwachs. It is not true for multi-stage alternatives, which can operate where single-separator designs are unable to do so.

This diffuser set-up has been argued above already. The assumption made by Halbwachs and YLec are the same, that the density of reinjected water is the same as the zone. The MTR specifically calls for sufficient density difference to remain a separate sub-zone of the URZ. The problem is thus preventable and the conclusion unsupportable.
The argument, once again, only applies to the inherent weakness of designs. Examples include (1) single-separator designs, and (2) a failure to use the available controls of density. 

Mixing in the URZ

These ensure that densities are sufficiently different to remain unmixed in the URZ. The balance of this argument falls away as the base assumption is wrong.
The argument was simple and clear. The fundamental and best protection of the lake against eruption is to retain the current density structure. This must be retained forever, if possible, even if that requires long-term intervention to keep it stable. By re-injecting deep water into shallow water, the main gradient layer (chemocline) will weaken and then disappear. It may then take centuries to re-establish the stability structure and the safety it ensures.

If there is a theory that this will create a stable and static new Main Gradient, it is wishful thinking at best. Due to the stronger sub-lacustrine inflows above the current Main Gradient, this gradient will migrate upwards and disappear faster than before. The 190 m gradient is too high to retain much pressure (~19 bar vs ~26 bar) and therefore less gas storage.

As the gradient weakens, gas can migrate through it and will sharply increase gas partial pressure below the 190 m gradient. All benefits of stability will be rapidly lost. The lake will be a more dangerous place before the first harvest period of 50 years is complete. This theory is dangerous. KivuWatt is practicing this now at a smaller scale. It is already showing evidence of weakening the main gradient and compromising lake safety.

This Fig. 3.2 graphic has a fundamental weakness. It is an equilibrium-state calculation, not based on a dynamic state. Let me put this simply: If you open a beer and leave it so for 24 hours, most of the CO2 gas will have escaped. But it only approaches equilibrium 24 hours later. But the residence time in an extraction system is 2-3 minutes, over which time a far smaller fraction of a beer’s CO2 will escape.

Dynamic vs Static:

Dynamic curves are very different. Likewise even the green curve, %CH4 recovered, is over-ambitious. 100% recovery is reached at much shallower depth in a dynamic system. It won’t get there with 2-3 minutes residence time. The curves are probably 50% over-stated. Halbwachs apparently lacks the data to show a dynamic curve. After all, his theory in 2003 was that it’s impossible to extract gas with a separator deeper than 20m. His own test-work failed to collect the relevant data. Hydragas is able to extract and separate gas at 65 m depth by contrast.

If the review panel has no objections to Halbwachs’ proposal, it has much to learn on this critical subject. This statement shows a worryingly low level of subject appreciation and knowledge. It cannot identify glaring and proven problems with Halbwachs’ proposal. Considering KivuWatt’s dangerous application of it, it is time to get some help. It’s really time to “go back to school” to learn not to make such dangerous statements.

The statement “Plan A1/A2 and Plan B require conditions of the hydrodynamic stability of Lake Kivu” is an example. It’s confused and out of touch. It is simplistic and uninformed, akin to one made in 2007 by Dr Tietze. His view was that “The only good lake is a dead lake. Take the gas out quickly and completely in 50 years. Then we are done.”

His view was dissected thoroughly and rejected for its many flaws by the Experts in 2007-2009. Fundamental to our rejections was that the world still needs to be safe well after 50 years. The lake will be there, biogenesis will be there (despite Schmid’s revelation that methane is fossil). People will be around the lake and they will be placed in mortal danger. The danger arises mainly by elimination of the best natural protection against gas eruptions. That protection is the density structure. It must be kept as-is.

On the statement “We conclude on (Halbwachs, 2011a,b,c ; Guillaume, 2009) as follows. 

The definition and function of concessions is of major concern. The reduced performance of gas-lift driven flow-rate in risers is not explicitly referred to in the MPs but of concern for determining the end of exploration.”

Nothing stated above establishes any such rationale for your concern. Despite his theory of di-phasic flow, Halbwachs’ ability to create high-performing gas-lift is lagging the leaders. This italicised statement in the panel review shows a concerning bias. It provides little justification that stands up to inspection.

There seemingly exists an implicit distrust of the prior work Expert Group members. This is despite not having tested the arguments against Halbwachs’ paper. These are now provided. Two eminent COWI hydrologists did simulations and made presentations to the Experts in Copenhagen. They established that a stable re-injection lens could form in the given conditions. It would be a couple of metres deep and up to 20 km wide.

It is concerning again too that Halbwachs never sought to correct or update his paper for this panel review. It is nine years after it was issued and largely built on false assumptions. But he threw it again into the mix in a hope of not being found out for flawed assumptions. I suggest you set up a proper debate on the subject. It’s preferable to listening to one side only and pronouncing the above conclusion.
The Expert Group never issued published, formal working papers from its proceedings. Much of the work was consolidated by Hirslund in a 400-page treatise, shared among some members. This is still not published.

Halbwachs 2011 study

Halbwachs publicised his 2011 study to refute the MPs. But he made invalid assumptions in the paper as the basis of his argument. As a result, his paper is only true for a case mixing equal density discharges into the URZ. For the Plan A1 and supporting MTRs it is invalid.
The Expert Group spent almost two years, from 2007-09, dissecting Halbwachs and Tietze’s theories. They found them to be grossly flawed sometimes. So it is time-consuming to have to debunk them all over again. A major underlying flaw is their shared prediliction to destroy the lake’s density structure. This key structure is still widely acknowledged as the best natural protection against a lake eruption.
Hirslund has published a number of papers to describe his work and findings on Lake Kivu since 2009. I have taken the time to study them. Although few are in my field of expertise, they are a valuable source of insights into behaviours of Lake Kivu. One paper, jointly authored with me, is now published in Elsevier’s Journal of African Earth Science, January 2020.

https://www.sciencedirect.com/science/article/pii/S1464343X19303279. In this paper there is in-depth investigation of issues and ideas put forward by other authors in the field since 2009. There are also new ideas and findings on improving the safety of extraction.

(F) Comment on p28 (KivuWatt 2015-present): 

“However, to some degree the strategy followed by KivuWatt does comply with the MPs in the aspect of depth of re-injection and the diffuser designs which agree with the primary intention of the MPs.”
14 MTRs have vital requirements, serious requirements and good practice requirements. KiwuWatt is compliant with some less serious needs and non-compliant with the more serious.
But the MTRs are not a smorgasbord. They are mandatory, all 14 of them. Complying “to some degree” is not adequate. One good diffuser design does not excuse half a dozen non-compliances in other areas.
If anything, more MTRs are needed to tighten up KivuWatt’s further bad practices on a poorly engineered plant. Lawsuits initiated by KivuWatt are a political-legal argument against complying with the 2009 MPs. But these MPs were written six years before KivuWatt commissioned their platform.

Their lawsuit claims a “change-in-law”. KivuWatt reportedly preferred a “bootleg” 2008 early draft copy of the MPs, that a government official provided. But KivuWatt had been present, represented by their project technical director and ContourGlobal counsel in Copenhagen in 2009. Examination of the claims made in the lawsuit indicate that virtually all related to their poor engineering, rather than any change in law.
It may be legal practice to argue that prior law is “grandfathered” when it is updated. But this argument must be refuted when used to excuse placing millions of lives at greater risk. However, in this case there was no prior law.

Neither engineering nor construction were even started by time the MPs were first formally issued in June 2009. The relevant elements of the 2008 and 2009 MPs do not differ.

Should there be any access to view the proceeds of the KivuWatt vs GoR, there would be documentary evidence. Evidence both on behalf of the proponent and the defendant can be found there.

How would this in your view affect the current set of MPs or current operational practises?
(please specify the current number of the MPs that would possibly be affected)

It appears that the review panel scoured the earth for every negative sentiment, or every aggrieved proponent of debunked theories. This applies whether they were dealt with in the past or not. The same arguments are presented, without having addressed identified errors, false assumptions and unsubstantiated data. These prompted a previous debunking of the findings, conclusions and hypotheses in their work.

Curiously too, the work of KivuWatt has been presented here as a “good example”. In fact it has been more characterised by engineering and design flaws and lack of compliance. It demonstrates outright avoidance of compliance with technical and administrative rules. This lack of oversight provides clear evidence of no real knowledge and insight by the review panel. There is seemingly a willingness to believe anyone with a grievance.

As a result, there seems to be scarce constructive value emanating from this panel review. It is assembled with a suspicious mind-set, with most of the suspicion directed at the established experts and little directed at their critics.

This panel document did not identify the one MTR that was actually flawed. We acknowledge that MTR 5 on Plan B was flawed in its construct. But the panel document has falsely identified problems with other MTRs. These “issues” have not been established with any validity.

Why are conclusions offered in 3.1.5 on a series of contentions statements?

On p29, a summary of Conclusions is offered in the panel report. Most of these are somewhat contentious and unproven, including:

1. Our conclusions on previous discussions on the MPs. Before we continue presenting our review, we summarize as follows the existing recommendations and amendments about the MPs. 1. The concerns and proposals presented by Halbwachs (2011a,b,c) and (Guillaume, 2009) are explicitly related to the methane extraction procedures of the MPs and point to voids in the MPs definition of concessions.

Dealt with before in 2011 and can be rejected again and again for the same reasons. The detailed letter of 2009 to Halbwachs stands, unanswered to date.

2. At least the part of Halbwachs’ proposal to re-inject de-gassed URZ water into the PRZ (Table 3.1) deserves closer attention.

This is dangerous, not improving on retrospectively approving KivuWatt’s bad engineering and failure to conform to the MPs. It deserves closer attention again to justify its rejection and continued banning.

3. The discussion by Tedesco et al. and Nayar invites risk assessment for cases where methane extraction is relevant or significant.

The opposite was true. MTRs in the MPs were made more difficult to comply with in order to prioritise safety of methane recovery. The principles in order were (1) people safety, (2) environmental safety, (3) community benefit and finally (4) developer benefits. We did not deviate and that is why KivuWatt, Halbwachs and Tietze all found the MPs difficult to comply with when issued. Their objections followed.

4. The methane extraction by KivuWatt since 2015 can serve as probe for the practical applicability of the MPs rules and guidelines for safety, inspection, on-site and nearfield monitoring, concession demarcation, legal instruments etc.

KivuWatt’s practice, both before and since the 2105 start-up, demonstrates gross errors in engineering. They show failure to comply with the MPs. They adopt their own interpretations of the MPs – neither grounded in the letter or intent of the MTRs and MARs.
KivuWatt failed to consult or take heed of the advice of experts. They didn’t even to attempt to understand the mandatory requirements for design. It is not a probe for practical applicability. Theirs is a lesson on how not to engineer, design, build and operate a gas extraction facility.
It could, however, be a lesson on how to stress-test the rules. They provide a check on authorities’ ability to verify and monitor circumvention of compliance.

5. Despite the exhibited knowledge of many aspects of Lake Kivu and methane extraction, we may appreciate Hirslund’s arguments more if his papers where (sic) more concise and his papers discuss the observations of, and with e.g. Ross and Sommer of EAWAG.

This statement is rich. The MPs are criticised for being too concise to explain the reasons behind all the Plan A1/A2 etc. When the rationale is presented by Hirslund in detail, his papers need to be more concise. Damned if you do, damned if you don’t.
There is virtually no material in this section of the panel review that seems to come close to being a valid basis for overturning any of the content of the MPs. The exercise seems to have been completed by calling up all aggrieved parties to do their best to undermine a respectable body of work by any means possible.

What did the Expert Working Group use as reference to derive and prioritize their recommendations. What was their utmost danger, in what case/scenario did methane extraction reduce or increase lake safety?

(A) From the statement on p30, “Introduction: The initial objective of the MPs was to extract methane safely from Lake Kivu for power generation, while reducing the risk of a gas blow-out under the conditions of preserving density gradients. The MPs demand the safe design of installations. This review panel, however, is not aware whether the MPs prioritized recommendations on risk assessments in which methane extraction may contribute. Neither is the panel informed whether such risks have been assessed and mitigated in the design of methane extraction facilities.”

On the Initial Objective:

This statement is a basic mis-read of the MPs. The MPs were written in good faith to ensure safety of the lake from a catastrophic limnic eruption. Extraction of methane for power generation was a government priority. In the process of finding that methane extraction was a key method for reducing the risk, the techniques of extraction became the focus to ensure that the method delivering the greatest safety would be determined and therefore enforced.
All methods that failed to improve safety, or degraded the natural safety mechanisms of the lake, would be rejected.
Unfortunately, this review seems to be taken up as an opportunity to win arguments that were thoroughly rejected last time around. Hence the “afflicted parties”, such as Halbwachs and perhaps Tietze, are offering the same debunked theories again. It is as though they were never found to be so flawed in 2007-09.

On Risk Assessment:

Indeed, the whole three-year exercise was a total risk assessment in many parts about stratification, limnology, meteorology, microbiology, hydraulic stability, hydrology, biochemistry, water chemistry etc.
We were aware of risks from volcanism, seismic rifting, drought and toxicity that are within and specific to the lake. We studied them and consulted experts, such as Dario Tedesco and visited the Goma Volcanic Observatory. We modelled the impacts of reinjection of degassed water at many levels to figure out plume dispersion and double-diffusive layering.

As a team of experts in several fields, we set out to define the nature and extent of a full limnic eruption, as experienced at Lakes Monoun and Nyos, but in this case for a lake 10,000 times bigger. We wrote internally about that and quantified the possible casualties (2-4 million), the carbon release (~2 gigatons) to the environment and the impact of tsunamis on the lake as well as a surge in the lake level (major destruction of all lakeside cities and the severe flooding of Bujumbura on Lake Tanganyika.

Toxic Gas Clouds

We modelled the extent of toxic gas clouds including 2000 ppm H2S. We rightly feared that it was not our role to scare the people living there, but rather to reduce and remove the threat. We called for monitoring and warning sirens. Some of this is published in postings on Wikipedia as part of an exercise to elicit wider comment.
Knowing that there was little that we could do to prevent volcanic eruptions, or seismic rifting, we looked for how we could change the contents of the lake over time to reduce risks more precisely and with lasting safety effect. We didn’t want to go public with scare-mongering tactics. That was discouraged.

What is inferred in the highlighted statement is that we spent three years figuring out how to extract gas profitably, then failed to set up a one-day HAZOP review to determine the risks. Some of us figured out extraction economics independently, but it was never part of the discussions. It was, after all, the lower priority.

In fact the opposite is true: it was a three year risk and hazard assessment, with many mitigations, followed by an action planning exercise on safety matters and deeper protections. During these discussions I admit we failed to actually sit down and work out how gas extraction could be done profitably. The background to our discussion, with more recent and amplified learnings, was published in a 50-page detailed article in the Journal of African Earth Science in January 2020.

The point is made that we should have HAZOP’d the extraction plants. Since these plants are all unique designs, they must be HAZOP’s as they are designed. This is a mandatory administrative requirement (MAR) in the MPs. KivuWatt failed to HAZOP its design. It failed to involve external expertise as required in the MAR. This does not justify the review panel’s curious lack of awareness of the risk stance in the MPs. Some of us reviewed KivuWatt’s design failures, after the fact. There is nothing more to be done within the MPs to protect against such poor engineering practice. Further, a design review was mandatory, but no review or competent expertise was called. Nor was there a Bilateral Regulatory Authority created to enforce one. 

On Natural Risks Analyses:

Firstly, has the BRA re-appeared after 10 years waiting? It was a primary recommendation of the MPs in 2009.
Secondly, the proposed risk scenarios were assessed in great detail before. But, as explained above, the multi-disciplinary exercise was completed as the focus and main purpose of the many meetings and years of correspondence between experts. I don’t believe that any of the experts was unaware of the reports issued by Tietze, Halbwachs, Kusakabe etc. The reference list of the MPs attests to that.
It was out of such exercises (we didn’t use the word scenarios) we reviewed the fundamental methods of gas extraction. We reviewed many, including those proposed by Halbwachs afterwards. Even those used by KivuWatt afterwards, in conflict with the MPs, were simulated for outcomes. They failed because they increase the levels of danger in the lake.

None Escaped Review

None of the ten listed scenarios escaped our review. Perhaps your list should be extended to show a limnic eruption with a toxic gas release (2000 ppm H2S release is fatally toxic within a minute or two). We have as experts been consulted by oil exploration companies, for example, on seismic testing. We also recognised that marine design included designing for such eventualities such as collision by large vessels. We studied the flight paths of aircraft taking off from Goma and Gisenyi airports, flying directly overhead some installations.

As mentioned above, HAZOPs, attended by experts at the request of a “BRA”, would have at least prevented: 

1. KivuWatt from building multiple non-compliances to the MPs, especially re-injection into the PRZ. 
2. Halbwachs from failing to design seaworthy platforms on two occasions.
3. KivuWatt and KP1 from deploying improper anchors for the bottom conditions.
4. All platforms built to date being without sonar and other detection of underwater eruptions. These should be combined with warning sirens, sealed escape rooms with fresh air supply, and
5. All vessels being built to float when a cloud of gas bubbles reduces a vessel’s buoyancy in water by up to 50%.

In simple terms, all of the above was considered. But since most of the items are location specific and plant-design specific, we can’t pre-judge. The MPs are only written to specify that a comprehensive HAZOP process must be followed. This must be done for each installation, with invited experts. Compliance is BRA or national government responsibility, not a task allocated to the authors of the MPs.

For earthquakes and volcanic eruptions, no design is adequate to exclude a risk. Once again, if an installation is close to shore the response is different to another far from shore. The best we can do for averting the ultimate limnic eruption is to ensure safe reduction of gas levels. This should be within the first 20 – 25 years. This is to ensure that the level of danger reduces below 1% of what it is now. That is slow but it cannot be done without building gas production facilities. The must be completed with the right designs, and operating them for 20+ years.

On Anthropogenic Risks:

In retrospect the anthropogenic risks come from a rash of non-compliant installations such as KivuWatt, KP1. The same risks would apply to a few other proposed installations by Halbwachs, Tietze, Symbion Power. There seems to have been rampant cases of poor engineering, misinterpretation of the MPs. There has been a flagrant disregard of the MPs and the rules therein.

That is why many such risks were identified, considered and then they were excluded in the MPs. Each identified problem was proscribed specifically through the MTRs. Despite that, notwithstanding warnings to the authorities, bad practice continued to cause a rise in anthropogenic risk. The lack of a BRA enabled bad practice to proceed unhindered. It is ironic that this panel review seems to disregard such risks and focuses an grievances against the MPs instead.

On the Lack of Risk Assessments in the MPs:

The Review panel is made up of fully paid professionals appointed for the purpose of this review. They are well compensated for every word they read or write. The more time spent, the greater the cost of the total review. It is richly ironic what this review panel expects of us Experts who wrote the MPs. We are expected to have read and referenced everything in the literature. The highlighted listing is random and vaguely referenced work, much of it post-dating the 2009 publication of the MPs.

All Experts that wrote the MPs, in contrast, donated all their time on a pro-bono basis. That amounted to three years of part-time work, costing each Expert between 1000-3000 hours of unpaid commitment. If viewed as an opportunity cost, their contributions were worth anything from $150,000 up to say $500,000. For some, the work continued with thousands of additional hours in research and writing of papers, particularly Hirslund.

Much of the expertise applied to the creation and updating of the MPs derived from lifetimes of personal experience. These included observations on the lake, working on experimental platforms, data gathering vessels and gas extraction platforms. In a field with a dearth of experience, a lack of data and too much misinformation, the effort and result were remarkable. The intent and commitment to the principles ensured a good result after much internal debate.

The unsubtle implication in the review panel’s report is of lack of completeness in research, method and know-how. This slight of the Experts is petty and mean. We could offer a counterpoint. The review panel’s authors have a seemingly naive or scatter-gun approach to information presented herein. It demonstrates distinct biases against the Expert Group and seeminly none against critics. Reviewers show deep scepticism of the Experts and an alarming inclination to be misled by others. The review is in dire need of a review itself.

This apparent bias tends to question or demean the original Experts. It highlights the information and opposition of their detractors with unquestioning enthusiasm. Some radical new theories about the methane being fossil-based and non-biogenic are inexplicably taken on board as “probably true”. This position is in defiance of almost a century of prior evidence to the contrary.

On Underwater Hazards – Turbidity Currents, Internal Seiches:

The “importance” of turbidity currents, being called “lacking” in the MP’s assessment, better reflects the reality than this vague and alarmist statement. There is a localised incidence of small rivulets and streams entering the east and west sides of Lake Kivu. They deposit some sand and turbid water, but at levels that are uncharacteristically low for such large lakes. Lake Kivu’s catchment is unusually small, being little larger than the lake’s surface area.

The major portion of the lake’s rain catchment is located on the north shore lava beds. These the lava beds have no surface rivers nor sediments flowing into the lake. But rainwater rather enters the lake via sub-lacustrine inflows through lava strata. To suggest that turbidity currents from the north constitute a major safety factor is misleading.

Most gas extraction plants will therefore be far from any influence of such turbidity currents. As a factor, of importance to any but the KP1 and Halbwachs platforms, it is virtually irrelevant. It may be a design factor in anchoring pipelines to shore, where some anchors may be closer to sand fans.

On “massive landslides” and “strong internal seiches”

I don’t believe these are even of the size and impact to be rated in the top 10 risks for gas extraction plant. By comparison, volcanic and seismic events are at the top end of the clear risks. In our discussions in preparing the MPs, we made reference to the dangerous equivalent energy requirements. An example was a multi-megaton nuclear explosion being required to lift gas-rich water sufficient to create an erupting plume.

For a lake of this size, it is known as having a very small catchment, relatively small river inflows. The bring in little sediment, other than the likes of this one sandy stream at the Sebeya river. This stream does deposit sand onto a steeply-shelving bottom, as evidenced by the lake bathymetry. This can, and reportedly led to occasional slumps of sand, with slips occurring up to 1km from the river mouth. Local reporting refers to swimmers that disappear swimming off the beach at the nearby Serena Hotel in Gisenyi. This is a localised problem far from the likely locations of GEFs.

However, these are small instances. Some of them have been observed, causing a rising plume of bubbles. One was photographed by the KP1 construction crew in ~2008-9. Some canoes, carrying sometimes dozens of people, are reputed to have sunk in the same area. These same boats often travel with 100-150mm of freeboard, making them vulnerable to sinking if the boat is rocked. Loss of buoyancy of such vessels is a persistent problem due to poor marine safety practice on the lake.

Most of the gas extraction plants will be located in 350 m or preferably 400 m plus depths. These small, localised sand deposits will not reach the 5-10km minimum distance from the shores to the GEFs.

This same potential is completely absent when accessing the lake from the north shore. The north shore hydrography is made up by several hundred metres depth of steeply shelving lava beds. The bathymetric survey identifies deep cavities over 300 m depth within 1.5 km of the shore. More open deep water is evident within 2 km of the shore. There is no potential for sand deposition on the north shore, anywhere west of the Sebeya river. It is limited to the sand that flows from that river mouth and deposits close to shore.

In a related statement under 3.3.1

Which states “Although open for discussion we consider landslides and river sediments yielding turbidity currents by fluffy bed layers the potentially most dangerous external phenomena that may displace anchors, break risers, pipes, anchor chains, and create platform instabilities.”

The above text is overstated as being dangerous phenomena. The only thing remotely testing anchor systems is the wind-induced surface currents and any induced counter-currents below. Having spent six months on the lake, building and operating pilot plant, the strongest currents were at surface. These are driven by the May-to-September dry-season winds, have a circular pastern around Idjwi Island.

Locally the direction of winds was not all south-to-north. The currents’ directions could be from such surface currents turning back south as they approached the north coast. In our pilot-plant location 1.5km off Cap Rubone, there was a WNW direction of the surface current of up to 1 m/s. Later in May the strength of the currents was greater but difficult to measure. This direction of current flow is borne out by maps in the following page 40.

A greater “danger” was posed by fishermen at night. On two occasions they had boarded our platform and cut anchor ropes to steal some length of the polyurethane rope used. On one occasion the unanchored platform drifted 2km south-west overnight, driven by current rather than wind. 

In a related statement under 3.3.3

Which states “For creating a level playing field for constructors, investors, insurers, and operators official references to extreme meteorological conditions. These are wind, lightning etc. Surface waves and currents need to be formulated and prescribed as boundary conditions.”

Is this a Eurocentric view of “extreme”? Lightning is a regular seasonal thing in tropical Africa, occurring frequently, throughout the wet season. The southerly, stronger winds are a diurnal feature of the “dry” seasons, with medium-strength winds prevailing every afternoon.

The waves patterns arising from this wind are highly predictable and are part of a normal design basis for barge or platform construction. Design for fatigue conditions is essential, an element of design missing from the two platforms designed by Halbwachs in 2006-2008.

Slightly less predictable are the afternoon squalls that arise from almost daily tropical storms in the wet season. The wind arises and subsides within minutes.

From viewing different designs of floating platforms on Lake Kivu, a range of standards may have been adopted. High-end guidance is available for the design of oil platforms in the Gulf of Mexico. There one must design for sustained gale-force or hurricane-force winds. One adds the simultaneous collision with an untethered vessel of the type commonly used in that body of water. This was the standard we deployed when completing a feasibility study. Clearly some designs, such as Symbion’s, do not adopt anything close to such a standard. They have designed platforms that weld sea containers together. Such sea containers are totally lacking in sufficient structural strength.

In a statement under 3.3.4

It states “For more discussion we refer to the review by the environmental committee about GHG emissions and renewable energy sources. And we just quote their comment. “Formally, only the regenerated fraction of the methane can be considered as a truly renewable energy source. The other fraction should be considered a fossil fuel”. This is in line with BP1.1a which states. “In the long term, the total rate of methane extraction from all operations should equal the rate of estimated natural increase”.

Isn’t this conclusion at best hasty, and very far from being consensus? Consider all the potential reasons for surveys that indicate a reduction of methane in situ. One should examine potential causes of an apparent halt or reversal of methane accumulation. Is there any thesis on how “fossil methane” gets into the lake? Is it from the purported but unproven graben underlying Lake Kivu?

The following questions are not asked or answered in the text:

1. Was the new method accurate in the recent surveys?
2. Was the method or equipment adequate or accurate in any of the previous surveys of equivalent concentration and depth?
3. What are the comparable trends in carbon dioxide inventory?
4. What are the partial pressure measurements of the same surveys?
5. is there evidence of a die-off of the bacterial and other organisms responsible (methanogens)?
6. Tietze wrote about the errors in methods used by prior lake surveys. Problems related to the equipment used to collect the gas samples. Has the method used resolved any, let alone all the deficiencies?

Wijdeveld has rightly questioned the equal-weighting of the new methodology deployed by Schmid with a series of earlier methods of more proven efficacy.

Questionable Conclusions

The conclusions apparently drawn by Schmid in 2019 are a hair-raising departure from virtually all past findings. I question the method as it does not seem to be proven at depths where the main gas resource is stored within the lake.
This set of measurements is hardly a basis for overturning all past work. It raises a concern, but requires comprehensive proof. Before that, one cannot redirect from the underlying thesis that sustained all work on the lake’s development since 1986. This applies even less from work in 2003-2019.

This conclusion on whether there is no detectable increase in methane mass is moot. Whether methane is renewable or not is concerning too. What drives such a potentially serious departure from the science of the past 83 years? What conclusions may be drawn from the Schmid finding? Has there has been a complete die-off of the bacteria responsible for methane generation. This is curious and unexplained in this report. Not even a simple test such as carbon-dating the methane or looking at isotopic counts of the carbon is referenced in this summary. Much more work is required to consider overturning our understanding of the nature of Lake Kivu.

The current set of MPs, despite the extensive criticism and even defamation have held up under inspection. The aggrieved parties questioning their content have failed this far to elaborate any substantiated problems with the work and its development.

Members of the original Expert Group see a need to tighten up on bad practice on Lake Kivu. It is evidently proliferating without a BRA in place to ensure compliance and to sanction avoidance or non-compliance. Further rules may be required to tighten up on loopholes and new areas of concern.

(A) There seems to be a lack of insight and clarity in the panel review on this topic, 

i.e. “The theoretical maximum electrical energy (example given below and in Appendix C) derived from methane stored in the lake is fairly well defined or, given a limited period of extraction, also the upper limit in electrical power generated is fairly well defined with a 10% tolerance in economically extractable methane volume.”

The actual gas derived from the lake varies by extraction technology, parasitic energy consumption. Net power out is impacted by power conversion efficiency. The amount of the gas reserves that can be accessed by any one extraction method varies from 46 to 100%. The variability of all of these factors is significant, each introducing much greater than 10% variance.

Overall, the variance may go from 10% to 51% in net energy output. The graphic below demonstrates the five factors to be considered. The variance is highly significant, with the 10% to 50% range being the difference between the best and second best.

If the MPs are applied to the Plan A1/A2 model, consistent output is possible. Figure 3.6 seems to adopt a fade-out of capacity as the source is diluted. But no basis is shown to confirm that underlying hypothesis, other than it being a version of Halbwachs work. It is highly impractical as a solution and no basis for a commercial power supply plan.

A more thorough analysis is required than this loose set of assumptions. It would be more appropriate to evaluate each available technology in play and evaluate the factors based on a particular design of extraction plant, its operating set up, its power output based on equipment selection and gas quality.

Only then can any evaluation be made of total potential output, based on who gets to do the project. Averaging the ranges quoted as a basis for projections is essentially meaningless. This Figure 3.6 Leest graphic is not useful information. The graphic is misleading as it does not relate to how one would develop electrical power from the resource. One does not start with high production and then decline over 50 years for economic reasons. 

One starts with a ramp up of installations, builds up to a plateau and then sustains at that value until nearly exhausted.
The graph starts at Year 10, so no ramp-up curve is shown. The apparent fade in power output and the efficiencies shown are not fully representative of practical possibilities. As noted above, it looks a bit too much like the Halbwachs resource dilution theory.

One should create incentives to operators for achieving maximum overall efficiencies. These should be in agreement with one of the objectives of the present MPs (Section 4.1, MT12). Such an incentive should be licensing the volume of pumped-up water from the relevant depth zones. This should be a primary control on concessions. It is more practical than licensing the extracted methane mass or the output electrical power. This has been a consistent theme of the experts in the MPs and in subsequent presentations to forums on lake development. Insofar as this chapter reinforces that imperative, it is useful.

KivuWatt has been non-compliant in its reporting of operational data, including power output. In the MPs, a mandatory administrative requirement was this reporting. At best it has been sporadic, and in the case of KivuWatt it has been a consistent non-compliance. This requirement was way beyond annual reports, it was needed at least monthly and preferably recorded on a daily basis to an accessible database.

How to deal with granting concessions before these are well defined after this Review of MPs?

(A) The Review Panel gives undue credence to Halbwachs for his opposition to concession policy. As follows: “The applicability of defining a geographic concession in a free-moving water body rather than in low permeable rock or soil such as in oil and gas recovery requires more clarification than the MPs provide. In paragraph 3.1 we referred to earlier discussions by Halbwachs (2011c) and in workshops (NCEA, 2007, 2009; LKMP, 2011).
The report (Halbwachs, 2011c) presents with comments and details the potential concessions in the Democratic Republic of Congo as well as in Rwanda, whereas other studies are devoted to Rwanda only. The report (Halbwachs, 2011c) notes that a much wider optimisation of concessions is needed considering all criteria cited. The non-existing Bilateral Regulatory Authority (Figure 4.2) could have directed such studies and observations more equally among DRC and Rwanda territories.”

These two paragraphs spell out nothing more than Halbwachs taking issue with concessions. It is consistent along with his opposition to every other element of the MPs. The concession policy would not normally have been a function of the Expert Group. Except that the government of Rwanda recognised that they needed guidance and asked the Experts in Copenhagen in 2008.

That guidance came in the form of two parts: mapping geographic location of GEFs and allocating resource quantification.
(1) First we recommended that a concession needed to separately define geographic space for a concession. (Hence the development of a “pie-diagram”, centred on the deepest point along the common DRC/Rwanda border). This was to give access to deep water, allowing each concession to work for the full lifetime of the resource.

(2) Secondly we quantified (with the information validated by 2009) the resource by zone (LRZ, URZ and PRZ). The total resource was divided by 10, while the resource by zones was also divided into 10 slices. This was displayed in terms of a “Resource” pie-chart, with an indication of the potential; for power generation by zone. These power potential production figures may no longer be accurate, at least the volumetric draw-down. Draw-down is calculable in cubic metres per hour of resource water by zone, should be close to correct. (Assuming 50 years is the duration of a concession’s total life).

Halbwachs Theory

Halbwachs’ difficulties with concessions are not explained in the Section 3.3.8 notes. However, his notation in papers issued at about the time identified deep-water points close to shore as proposed extraction sites. This concession methodology is not useful and cannot be made fair to all concessions. It suits his GEF design because they are small units without much scalability. He can only achieve this by numbering up, and therefore need a shore location. Given that, none of these locations had depth close to 450 m,  desirable for long-life concessions. Given his proposed optimisation of concessions, he offered plant site locations which are in no way capable of optimisation. This cannot apply to everyone’s concession, nor is it capable of evening out re-injection across the lake.

A final point should again be emphasized. Legacy method(s) of extraction, i.e. those of Halbwachs, Tietze, KP1, KivuWatt, Symbion/Shema, cannot coexist with MPs compliant systems. This is because they draw-down the level of the Main Gradient and reduce its strength. These changes compromise proper implementation of Plan A1/A2. This latter point requires precise levels of re-injection into the “knee-point” of a density gradient, just below its centre-line. Horizontal dispersion is then effective in creating a lake-wide re-injection lens that deepens with the accumulated re-injection flows.

If this concept is difficult for anyone to understand, we can arrange a presentation on its functionality to all that need to understand it.

How to deal with granting concessions before these are well defined after this Review of MPs? cont.

(B) Some misguided examples are being presented. Such as: “A subject treated generally in the present MPs is avoiding and monitoring interactions between concessions that may reduce density gradients or mutually hinder the execution and time span of Plan A1/A2. Though the MPs set some limiting rules for mixing and recommend detailed computational fluid dynamics. (CFD) simulations are about local mixing of and with dedicated mixing devices for re-injected water (MP, MTR5).”

The CFD simulation is attributed to Morse in 2016 and illustrated in Fig 3.10. It follows a similar misconception that Halbwachs and YLec wrote about in 2012. It completely misses the key requirement of the Plan A1 implementation. That key requirement is the re-injection at a controlled density, equal to the lake water density at a specific depth. This is about 5m below the centre of the main gradient, at 265 m.

The figure shows re-injection water colour-coded to have a density of 1001.8 at 280 m. It should have been colour-coded green at a density of 1001 kg/m^3. The flow is shown to be initially horizontal for a few metres before it plunges through the weaker 310 m gradient. It settles at about 320 m. This set-up is exactly how KivuWatt and Symbion are set to operate. i.e. They are designed-to-fail to comply with the MPs. It proves nothing other than KivuWatt/Symbion have not tried. Nor have they understood how to design a water circulation and processing system to comply with the MPs.

Chen-Millero

The Chen-Millero calculator was provided by EAWAG in 2009, including to KivuWatt. It provided the data to calculate the depth at which to separate water. It was designed and issued to calculate how to assess how water, extracted from any given depth, would re-settle. This must be at a required depth in the same zone. The controllable variable is carbon dioxide removal. This is determined by the depth of the uppermost separator and the depth of extraction.

While there are limits to what can be achieved, we can extract water from 355 m and resettle at say 315 m. It is well within the achievable range. That is how to achieve plan A2. For Plan A1, water extracted from say 305 m can be made to resettle at 265 m. i.e. Plan A1/A2 works.

However, achieving Plan B, was conceived as a fall-back plan in case of not being able to run Plan A1. It does not yield a practical, economic solution. This is because the uppermost separator would have to operate under a partial vacuum. That is needed to achieve sufficient carbon dioxide removal. CO2 removal without vacuum cannot yield re-injection water of low enough density (equivalent to 265 m depth). That is likely way too expensive to be economic. Changing the point of re-injection to 240 m makes the situation even worse, causing critical long-term damage to the Main Gradient.

KivuWatt, was offered assistance to resolve this and other issues at the 2009 Copenhagen conference. They refused to engage in any discussion. I approached them to offer my assistance on resolving their technical difficulties with developing a compliant solution. The ContourGlobal lawyer present ensured that the KivuWatt technical lead was there to listen only. He was not permitted to comment, discuss issues or to answer questions. Simply put, KivuWatt “shot themselves in the foot“. It showed their uncooperative attitude and disregard for the MPs and the Experts, which persisted to today.

How to deal with granting concessions before these are well defined after this Review of MPs? cont.

(C) The following assertions, though generally on subject, pick bad examples and misdirection. It is to try disprove the MPs on Concession issues i.e.:
(1) “Yet, horizontal differences in salinity, temperature and gas concentrations are created per concession/platform in the depth zones. This is where deep water or wash water are re-injected (such as in the Upper Resource Zone for circulation A1). It may induce weak horizontal density-driven currents.
(2) In addition, natural phenomena such as wind-induced internal oscillations, horizontal eddy patterns (vortices, Figure 3.7). A general horizontal circulation may apply. They contribute to an uncontrolled exchange of matter between the upper resource zones of the concessions.
(3) The MPs do not consider these larger scale 3D hydrodynamic phenomena. Nor do they provide the licensing authority a methodology for controlling or monitoring interactions between concessions. Simulations of hydrodynamics and transport require very precise specification of the density of the returned water. Same with the receiving water, including the temperature of the return water. Small density differences between the model assumptions and in-situ operation will result in large errors for model predictions. The horizontal exchange and dispersion becomes an urgent issue in view of reported ongoing plant developments.”

(Response 1) 

This sentence on “horizontal differences” is vague and unconvincing. The collective factors affecting density and driver of horizontal dispersion of the re-injectate are sufficiently modelled. The Chen-Millero spreadsheet ensures that the level of re-injection is close enough to sustain the desired horizontal dispersion of lenses. After passage of years of operation, weather factors, salinity changes and other nuanced variations will vary the density of re-injectate. So to the water data at the calculated depth. The likely changes are not enough to compromise the re-settling of the plume into the right depth.

(Response 2) 

You have the wonderful benefits of ten years more research, monitoring and data from operations. None of this was available to the Experts in 2007-2009. This statement on the impact of oscillations and vortices displays no better insight than we had back then. It only fatuously questions us on why we didn’t have the data and models at the time.

We were similarly concerned about the same oscillations and current patterns causing perturbations that could affect mixing of layers. There were many discussions about 1-D, 2-D and even 3-D models. The outcome was that we did not have the funds nor time to perform 3D models, though we liked the idea. 1-D models were considered irrelevant because they could not represent the lake effectively.

We settled on 2-D models. They provided a clear, if not totally irrefutable conclusion on many of the problems created by bad practice. Examples are such as what is illustrated (in 2-D) in Fig 3.10. That genre of bad practice was the far bigger problem. But in the text, too much is made of “wind-induced oscillations and eddies” that are frankly very minor problems. This is by comparison at 265 m or 315 m depths. It is wonderfully easy to call for giant 3-D models to resolve understanding of marginal effects. But this is at the same time minimising or ignoring the gross effects of much more. The most important malpractice is re-injecting at the wrong levels. Get some perspective!

(Response 3) 

For the first part of this statement, see the response above. For the second, all of that was provided for in the MPs by setting a precise plan, i.e. Plan A1/A2. it required ongoing measurement of data and monitoring of plumes. To spell it out clearly, that provided both a methodology and monitoring. The statement is therefore both false and misleading.

(Response 4) 

The specifications are precise, i.e. “the re-injected water must settle at 265 m.” With the Chen-Millero model, this density is precise to five significant digits. How much more precision is required by this statement? The last sentence on “result in large errors for model predictions” is therefore nonsensical.

Horizontal dispersion, if implemented to the rules, will not present a problem. By contrast, the gross distortions of the lake stratification caused by KivuWatt are a problem. Similarly, those proposed by Symbion, and carried out at small-scale by KP1, were all problems of significantly larger impact.

The urgent issue is not as described in this paragraph. It is to get the concessionaires to work to the rules in the MPs (Plan A1/A2). These plans are still a far better solution than the outright failures of KivuWatt and others to engineer accordingly. They are creating a significant potential for destabilising the lake permanently.

The proposed concession policy was inserted into the MPs at the government of Rwanda’s request. It has been included there as guidance for the authorities responsible for their implementation and licensing. There is still a need, as demonstrated by the poorly constructed concessions in play.

The elements of importance to governments, in order to control their resource use and licensing process requires the following:.
(1) Geographic locations or areas for a concession-holder to operate and route pipelines.
(2) A defined resource quantity and draw-down rate provide equal resources to each to use.
(3) A defined term for exploitation of the resource quantity is decided by governments, but was recommended as two terms of 25 years.
(4) Any concession designated by output (i.e MW power output) should be cancelled and issued as resource-defined concessions as in (2).

Are the 2015-2019 near-plant reports evaluating horizontal spreading of reinjected water in agreement with the desired function of concession? See previous discussion/section.

The question on this section asks whether the desired function of the concession matches the reporting on monitoring results. The opposite must be asked, i.e. does the data show compliance with the concession’s intent and requirements? To illustrate how this is misdirected, some examples:

(A) The granting of concessions may proceed faster than the acceptance of clear rules for concession governance and monitoring, see the lawsuit in chapter 2.

This is a KivuWatt-favouring statement, implying that rules were unavailable on time for their concession negotiations. This is only partly true, because the 2008 bootleg copy of the MPs did contain similar graphics (updated in 2009). The same guidelines on geographic concessions outlined the same resource-sharing concession concept. At the time the detailed survey and official concession policy map by Hirslund was not in place. But it was available in 2011. There are some minor differences in the shoreline intersections, which did not affect KivuWatt.

The 2008 bootleg copy of the MPs was one of at least seven different drafts internally circulated that year. The core summary statement of concessioning policy was:
“To achieve these flexibilities, we recommended that governments concession gas extraction operations thus. They must co-allocate a geographic area of operation and a portion of the gas resource to each concession.”

Despite this guidance, ContourGlobal – KivuWatt managed to secure a concession that was expressed only in output terms. i.e. They were concessioned to produce 100 MW of grid-power. It had no reference to the inputs required. Therefore, at: 

(1) relatively low efficiency at which KivuWatt extracts gas.

(2) limited (single – LRZ) zones from which it extracts

(3) high consumption of parasitic energy to run the barge operation, and finally.

(4) modest efficiency of the selected gas engines, KivuWatt over-uses resources relative to policy.

Resource Over-use

These are, at best, modest efficiencies. A fully developed concession of 100 MWe of output could consume 30% more than Rwanda’s resource allocation. That is more than recommended to have been allocated equally to five Rwandan concessions. Further, KivuWatt has the intent to extract only from the deepest LRZ zone, which is richer in gas than the URZ. Symbion had no intent of extracting from the URZ at all. But they elect to destroy it through dilution with re-injectate.

Further, KivuWatt had not fully designed or built any GEF before the June 2009. After the first issue of the official MPs, they “leaned” on government implying legal action if made to comply. In fact, their GEF designs did not comply with MTRs 3, 4, 5, 6, 9, 10, and 12 of the 2008 version. They have not complied with MARs 1, 2, 3, 4, 6 and 7 either. Symbion/ Shema is similarly failing to try to comply with them in their FS.

If one references the June 2009 Final Issue of the MPs, KivuWatt was non-compliant with the very same MTRs.  The 2008 MTRs above were substantially the same. Of the two additional MTRs, 13 could not be complied with while 14 added no additional problems for KivuWatt. Some MARs were defined more explicitly, but the subject matter was unchanged. MAR 9 was added, requiring inspection of underwater equipment before installation. The same non-compliances were present, whether judged against the 2008 or 2009 versions. Symbion also planned to repeat the same MTR non-compliances. In mitigation they at least made a better start on complying with MARs.

Change-in-law

KivuWatt asserted in a lawsuit that there was a substantial “change in law”. This was between the bootleg 2008 version and formally issued 2009 version. But this is not in evidence. The project was pursued in an unchanged manner, in defiance of directly-comparable clauses in both versions.

In fact, KivuWatt pursued a legacy process design that was prohibited by both versions. This prohibition was a little more explicit in the final and formal issue. This more explicit version of 2009 was issued, backed up with added simulation data. By then, the Expert Group had more time to simulate the comparable extraction methods. They could verify their dangerous impacts on the lake. By 2019, after four years of operation, the feared impacts were evident in monitoring data. At this point a BRA, if formed, would have at least suspended KivuWatt operations.

(B) Let us illustrate the previous challenge by first inferring some operational conditions of KivuWatt and subsequently demonstrating consequences for concession management.

This sentence on p42 is difficult to understand, even after six readings. Does it perhaps suggest that KivuWatt is experiencing difficulty with operating? Was this not primarily due to the outcomes of poor design? As for subsequent non-compliance, was the award of a concession was too early to have clarity?

It’s difficult to answer this question without being able to discern its clear meaning or intent. But let me clarify the time-line. The design period used by KivuWatt ran from 2008 to about 2012, while it was struggling to raise funding. There was plenty of time, i.e. 4 years, to do some thinking, and some design work. They had time to ask questions of the experts. But it seems that no-one there really applied their minds over this very long interval. KivuWatt and its engineers got no closer to a viable solution, showing no curiosity on what that might be. Either they didn’t know how much they didn’t know (likely) or didn’t care to know. Were they being wilfully ignorant?

KivuWatt’s country manager made a presentation at the 2011 Gisenyi conference of the experts. He candidly admitted that KivuWatt had little clue on how to resolve the engineering problem posed by Plan A1/A2. I appreciated his candour, it was refreshing. This was especially so from an organisation that seemed to lack any candour or openness.

The outcome seemed to be to choose a “least-worst”, non-compliant design and go with it. This was while trying to get away with it by disclosing none of what was required by the MPs. It’s a real curiosity, perhaps they had their lawyers making all the engineering and PR decisions.

(C) The density of 355m deep water subsequently re-injected methane-poor at about 240-250 m (Figure 2.1) cannot be matched to the water density in the Potential Resource Zone (Figure 2.2) by just reducing its carbon dioxide concentration.

This single sentence was enough for KivuWatt to know that their chosen solution could never be made to work. Why then did they persist in trying? It only got their design problems worse, and worse, and then worse again. This is the point at which someone should have made the decision to ask for expert help. It never happened. Instead it was left to lawyers to sue the government to recover some losses while their engineers muddled on.

The KivuWatt plant’s litany of engineering and design errors, cartoonish mistakes and multiple miscalculations makes  depressing reading. The balance of these four paragraphs on p43 is like reading a proverb, you know the one. The person who dug a hole too deep to climb out, so he decided to keep digging deeper. I find little point in commenting on the numbers as that’s a fool’s errand. I will say though, that the reinjectate dilution plan in the PRZ is a compounding error. This was anything but a solution to the problems of KivuWatt’s bad practice.

The urgency needed here has little to do with “active concession management”. It is more for KivuWatt to stop persisting with the disaster that they are making. They could perhaps re-start, with some proper engineering and design work that complies with the rules. Or maybe they should just give up and get out of the way. The LKMP is starting to witness the dire outcomes of the above lunacy. The impacts are becoming more serious by the day and the operation needs to be suspended for cause.

(D) On the “Preliminary conclusions and observations” 

In 3.4, the provocation promised is delivered. Therefore these answers are provided in similar tone to each statement. These are asked and answered as numbered on p43.

(1) An expert panel should assess and order risks involved in methane extraction for evaluating safety regulations and evaluating (our) additions of the Management Prescriptions.

I have disputed above-stated notion that risk assessment was not done or done insufficiently. That is false premise and should be withdrawn. The assessment was thorough and deep, working in a domain where some scattered survey data had been gathered. It was done where no valid production data was available. And it was done where widespread and deep subject matter understanding, of a unique freak of nature, was lacking. This latter case persists, if some of the curious narrative in this panel review is weighed up.

The MP’s drafting process was very substantially a risk assessment. For that reason, it extended what was supposed to be a week-long exercise called by the NCEA in March 2007. It was initiated to affirm the 1986 Reglements Socigaz (the first equivalent of the MPs). A week was never enough. But it started what turned into a three-year deep-dive of risk assessment of a lake that is a risk-laden phenomenon.

In the Documentation

I can supply graphic examples of dozens of email exchanges that eventually  led to calling a series of conferences. These were to question and discuss the risks and issues in a group setting, first in October 2007. This is where the size of the problem was simulated and stark nature of risks realised. Then in May 2008 we began to match solutions to the risks and issues. The exercise continued through individual efforts and email communication for another year. 

Only then, a final May 2009 conference was convened again by the NCEA. Despite the trenchant resistance of one expert on the supremacy of his theory, an unsupported theory he had yet to begin working on, we otherwise achieved unanimity. We were ready for publishing the MPs, under pressure from the GoR and the NCEA.

After lengthy debate, assessments, modelling, data searches and solution-crafting, the MPs created a set of constraints and rules. These created the bounds within which safe engineering solutions could be created and operated. The review panel should review its own level of understanding (and unsubtle criticisms) of this process and its drivers.  It was what resulted in the key decisions that are now embedded in the MPs. It was thorough, productive and completed by volunteers with great commitment to seeking answers and consensus.

Nothing New:

Nothing that has surfaced in the above 43 pages of the panel report adequately questions or convincingly undermines the MPs. Nothing convincingly contradicts the basis or substance of the outcomes embedded in the 2009 MPs. With hindsight some improvements are possible, some loopholes can be closed. Some data and hypotheses can be reworked. Some models can be improved with further data collected. Ironically the areas that we know require revision were not picked up at all.

Actually, let’s pause so we can stretch your provocative theorising to its limits and summarise it. “We have this new theory of everything, coming from the same place that Einstein developed his theory of everything. The gas is all fossil origin. It’s a conspiracy by the deep-state experts. Big Oil snuck it in there while nobody was watching. Nobody knows. The biogas was all a big hoax by the Ukrainians and the Chinese. Or maybe it’s more fake news from the Left-wing Press. Dead algae is only there to mess up anchoring systems, its dead after all and can’t make gas. The 1st Law of Thermodynamics was also a hoax and I have proof from my lawyer. See, I have the best words. I know more than all the scientists. The lake erupting is another hoax, believe me. Our version of the MPs will win in a landslide election. It’s perfect.”

In fact, dark humour aside, this was why the MPs themselves called for this review. There is, however, hardly any justification in the panel report to overturn the principles, methods and findings. But the debunked theories of ten years back must seemingly be debunked all over again. They lacked essential substance and merit then, as they do now. But we shall persist as it is too important to do otherwise.

(2) “1. Their report should serve as mandatory technical reference for licensing”

As one of the previous experts, we shall review this panel’s work to see if its quality and value supersedes the rigour, depth and breadth of the previous work, even with its budget 20 times higher than ours. Then we can judge whether the outcome is worthy as a mandatory technical reference. Is the plan to replace the MPs with it or to supplement them?

As the biblical cautionary tale reads: “Judge Not Lest Ye Be Judged.” Do the work first, get it reviewed by real experts and then decide whether it’s also becomes a worthy “mandatory reference”.

(3) “2. In-situ, on-platform, and on-line observations and forecasting of meteorology (wind, lightning etc.) and hydrodynamics (surface waves, currents preferably over the full depth) or platform motions should be included in licenses of GEFs as these are essential for safeguarding operations and are essential for determining the probability of exceedance for safe platform designs.”

This is a “cart-before-the-horse” moment. i.e. Go and do all the observations, meteorology and forecasting after you get a license to build the platform. Then model it all again and then decide whether you built the right platform? What if you hadn’t built it right? Start it all over again? Not a bad idea for KivuWatt, which certainly knows how to overbuild and underdesign at once!
What is the directive here? Do five years of all these measurements before you do anything? Is it perhaps, do constant weather forecasts to see if your platform was built strong enough? Does anyone on this team have real-world experience at all?

(4) “3. The adapted MPs should acknowledge the following. The increase in exploitable methane mass in Lake Kivu is not discernible and within 50 years should not accounted for.”

Who writes this? New sets of readings, with uncalibrated equipment, show that some methane has disappeared relative the prior data sets. Without admitting possible measurement error, the theory of biogenesis gets discarded, along with the 1st Law of Thermodynamics. It is replaced with “No discernible increase in exploitable methane mass means that methane is of fossil origin, i.e. can’t be renewable. So the methanogens were all imaginary and, therefore, we don’t need to look for any new methane again in the next 50 years.”

This is so startlingly “ballsy”; it can be put into a Monty Python show along with their Great Theory on Dinosaurs. Send it rather to John Cleese and his colleagues for a piece to mock scientists.

(5) “4. The adapted MPs should acknowledge the following. The upper and lower resource zones (beyond 260m depth) contain all economically extractable methane (concentration) of 40 ± 4 STP km³ (STP equals 1 bar and 0°C). Any increase in methane concentration in the potential resource zone or in the resource zone proper should not be accounted for in its present exploitation, concession governance, nor in the direct future (next 50 years), allowing time for formulating an equitable extraction policy between the different concessionaires.

This is deja-vu all over again…. a corollary of Point No 3! But this time we slip in a new formulation of equitable resource sharing. It’s simpler than that: Stop KivuWatt from robbing all of Rwanda’s LRZ resource and 30% of the DRC’s. Then do more measurement. Rinse and repeat for five or ten more years. That is the necessary proof. Then re-evaluate the resource trends and adjust the concessions up or down as necessary. A simple clause in the concession should allow for that.
The KivuWatt concession overuse is a much bigger problem and will cost both countries billions in lost and wasted resources. The size of this problem is much more serious than this particular suggestion can hope to resolve.

(6) “5. The adapted MPs should replace Plan A1/A2 by scenario PR1 in (Wüest et al., 2009), and suggested by (Halbwachs, 2011b), with methane extracted from the Upper Resource Zone and with deep water re-injected into the Potential Resource Zone. Compared to Plan A1/A2 this safe alternative is intended to facilitate a larger-scale, and economically-feasible energy production while safeguarding the lake’s safety, ecology and methane resources in both URZ and LRZ but neglecting potential profits from the Potential Resource Zone.”

Really? On whose advice and by which proven capability is this conclusion made? What about the marching orders in the Terms of Reference, requiring a review that includes the original experts? PR1 was studied as part of the discussion in the Expert Group reviews that led to the published MPs. 

It received no support. Neither did Halbwachs’ (2011b) look-alike version of the disaster that is KivuWatt’s design, as shown at the 2011 conference. The destruction of the Main Gradient and its likely consequences is a real crime against humanity. This is criminal for its reckless endangerment of a population of millions in the Kivu valley. Is that how provocative you want to be? 

The PR1 alternative is neither safe, nor productive, nor economical (see KivuWatt’s resource and economic performance if you wonder why). They use 3.5 to 5 times more resource per MW output. Their best options seem to be to ask for higher tariffs and to sue everyone.

(7) “6. The adapted MPs should acknowledge the following: The variability in overall efficiencies in producing electrical energy is significantly larger than the ±10% uncertainty in methane storage. Hence, incentives for maximizing efficiencies in methane to electricity conversion are first priority, as well as monitoring the performance in terms of electricity produced versus extracted deep water.”

I’m shocked. After the “gong-show” you are carrying on in items 1-6, finally some reality. But there’s more.
The first and major efficiency is in gas extraction, which can be improved to more than double KivuWatt’s. The second is in parasitic energy, which can be cut by 90%. The third is in power generation, which can be increased by 50-60% with better quality gas and generation equipment that needs that quality gas to perform. Good engineering and design is needed. 

See the diagram at the bottom for clarity. Kivuwatt (a PR1 proxy design) gets just 8-10% of the available energy out of Lake Kivu. Hydragas gets 38 – 51%, depending on using gas engines or CCGT for power converion. The detailed work-up to these numbers is available, if you ask for it. The difference is worth tens of billions to each country bordering Lake Kivu. Do you want to add robbery of a country’s resources to your crimes against humanity?

(8) “7. Some minimum of overall efficiency of energy production versus energy contained in extracted methane should be included in licenses of GEFs.”

Now we’re on a roll! Two valid, good ideas in a row. Now if you investigate, as in (7) above, you can get some real data rather than what’s floating around in your imagination. Consult the real experts.

(9) “8. Operational conditions such as fluid and gas fluxes and pressure on the platforms and their energy production should be provided on-line to the surveying authorities and should be included in licenses of GEFs.”

Too good to be true. This was in the MPs already, so yes again.

(10) “9. The MPs should define the physical function and define monitoring the intended evolution of a concession e.g. lake-wide horizontal diffusion and horizontal circulation of re-injected water.”

Yes, once again – the proposed monitoring that LKMP has been trying to do with very limited funding.

(11) “10. The scientific community should be granted (what: permission, funding?) to continue monitoring size and depth of chemoclines/isopycnals, the exploration of all major aquatic and sub-aquatic sources of water, heat and constituents, and the development and application of related instruments.”

Collect data for how long – 10, 20, 50 years? And then we can find something that we didn’t think of today. By then how much would have happened? Perhaps then we can explain in detail why after 10 years we lost the lake’s stability? And then how everything went south from there? You may be in time to do a post-mortem on your litany of mis-reads and misdeeds above.

What we have in the MPs is good. The concession concept was fit for purpose, but actual concession drafting by government was disastrous. Enforcement was worse. There was lack of scrutiny of poorly conceived and executed engineering and design, in the absence of a competent regulator. This led to a disaster of a first commercial installation.

• Items 1-5 on the above summary list are marginal to very poor recommendations.

• Items 6-9 have merit and should be considered for inclusion with existing MPs.

• Item 10 is not clear in its request for granting something, nor from whom. Is it a Christmas wish like Peace on Earth?