meeting minutes may 21, 2019 - nrdrwwsc€¦ · tim timmons, manager of corporate services, lacombe...

Meeting Minutes May 21, 2019 Page 1 of 4

REGIONAL WASTEWATER MEETING MINUTES May 21, 2019

COUNCIL CHAMBERS LACOMBE AB

In Attendance:

Members: Councillor Ken Wigmore, Chair, Councillor, Lacombe County Mayor Richard Poole, Vice Chair, Mayor, Town of Blackfalds

Mayor Grant Creasey, Director, Mayor, City of Lacombe

Others: Matthew Goudy, CAO, NRDRWWSC Preston Weran, Director of Infrastructure & Property Services, Town of Blackfalds Tim Timmons, Manager of Corporate Services, Lacombe County

Michael Minchin, Manager of Corporate Services, Lacombe County Jordan Thompson, Director of Operations & Planning Services, City of Lacombe Denise Bellabono, Administrative Assistant, NRDRWWSC Guests: Todd Simenson, Stantec Consulting Ltd. Joel Sawatzky, Stantec Consulting Ltd. Regrets: Myron Thompson, CAO, Town of Blackfalds Justin de Bresser, Senior Manager - Financial Services, City of Lacombe Amber Mitchell, Engineering Services Manager, City of Lacombe

1. Call to Order: Chair Wigmore called the meeting to order at 9:01am.

CARRIED

2. Adoption of the Agenda:

MOVED by Director Creasey that the agenda for May 21, 2019 be adopted as amended.

CARRIED

3. Adoption of Previous Minutes

Regular Meeting of April 8, 2019

MOVED by Vice Chair Poole that the minutes for April 8, 2019 Meeting be adopted as amended. CARRIED


4. Appointment of Auditors CAO Goudy presented to the Commission the recommendation for appointment of auditors for 2019-2023 fiscal years. A Request for Proposal was posted on the Alberta Purchasing Connection and the City of Lacombe’s website soliciting proposals. Three proposals were received, all within close margins of each bid. MOVED by Vice Chair Poole that the Commission renew the contract with BDO Canada LLP of Red Deer, Alberta and appoint as the Commission’s external financial auditors for the 2019-2023 fiscal years. CARRIED

5. Town of Blackfalds Request CAO Goudy presented to the Commission the Town of Blackfalds legal invoice for the Membership, Supply of Services, and Lease Agreements review. The request for the Commission to reimburse 50% of the fees, as the review resulted in meaningful changes to the Lease Agreements and minor changes to the Membership and Supply of Services Agreements, which impacted each individual municipality’s agreements to have changes. MOVED by Director Creasey that the Commission approve the expenditure of $6,658.99 from line item 05-2-48-23200 (Legal Fees), to cover the invoice submitted by the Town of Blackfalds

CARRIED

MOVED by Vice Chair Poole that any unbudgeted expenses of sharing for the Commission with a member be discussed and decided on by the Commission in advance. CARRIED

6. Lacombe Lift Station Director Thompson updated the Commission on the Lacombe Lift Station pump issues. Provided was Stantec’s Technical Memorandum 18, which outlined the coordinated investigation efforts and recommendations. At this point the investigation remains ongoing with the manufacturer pointing the problem being from excessive vibrations stressing the impeller components as being the likely causes of the impeller failure to both pumps. Steps being taken to determine the source of the vibration were summarized to the Commission. MOVED by Director Creasey that the Commission direct Administration bring pricing options to the next meeting for the power coming in and power to the motors with what options are available.

CARRIED

MOVED by Director Creasey that the Commission authorize the purchase of the Hydraulic Repair Kit at the cost of $12,000.

CARRIED

MOVED by Vice Chair Poole that the Commission authorize the Pipe Alterations to a maximum cost of $20,000 to be determined pending vibration measurement.


CARRIED MOVED by Vice Chair Poole to accept the Lacombe Lift Station and Technical Memorandum 18 report as information.

CARRIED

Meeting recessed at 11:00am Meeting resumed at 11:11am

7. Operational Report

The operational report from April 8 to end of May 21, 2019 was presented by Director Thompson with updates on the equalization storage system for the Blackfalds and Lacombe Lift Stations, site responses, and the Odour Management Facility. Contract items are covered in the Engineers report. MOVED by Director Creasey to accept the Operational Monthly Report of May 21, 2019 as information. CARRIED

8. Engineers Report

Mr. Simenson updated the Commission on construction progress, with small clean-up of seasonal deficiencies at three facilities and the completion of the equalization storage facilities remaining, which should be done by mid-end of June. MOVED by Director Creasey to accept the Engineer’s Report of May 13, 2019 as information.

9. Central Alberta Area Wastewater Area Meeting CAO Goudy informed the Commission of information regarding a long term plan on wastewater in central Alberta. In consideration of the new government, four of which are new ministers in the area, there has been a request to have preliminary discussions with all Chair and CAO’s of the Wastewater Commissions of central Alberta. Discussions would include grant funding and issues of mutual concerns.

10. In Camera MOVED by Director Creasey to move IN CAMERA at 11:27am with administrative representatives and Stantec Consultants to support the Commission to discuss the following item:

MEGlobal Stantec Consultants left at 11:47am prior to discussion on Stantec General Engineering Services Proposal

CARRIED

MOVED by Vice Chair Poole to move OUT CAMERA at 11:52am.

CARRIED


MOVED by Director Creasey that Commission direct administration work with Lacombe County to determine and coordinate the construction of required tie-in infrastructure to the North Red Deer Regional Wastewater Services system.

CARRIED

MOVED by Director Creasey that Commission approve the execution of a Professional Services Agreement with Stantec Consulting.

CARRIED

11. Next Meeting

The next meeting scheduled is for Monday June 17, 2019 at 1:00am in the City of Lacombe Council Chambers.

12. Adjournment:

MOVED by Director Creasey that the North Red Deer Regional Wastewater Services Commission meeting of May 21, 2019 be adjourned at 12:01pm.

CARRIED

______________________ ___________________ Chair Administrator

Date: April, 8 2019 Prepared by: Justin de Bresser, Senior Manager – Financial Services Presented by: Justin de Bresser , Senior Manager – Financial Services

GL5330 1Page :GL Department ReportDate : Jun 12, 2019 Time : 8:46 am

Year : 2019 Budget : FINAL BUDGET

Period : 3 Group by: Default

Account No. Description CC1 CC2 CC3 Current Year to Date Budget Variance % Used

REGIONAL WASTEWATER REPORTING

REVENUES

05-1-48-35110 Wastewater Volume - City of Lacomb -228,679 -614,052 -2,443,110 -1,829,058 25

05-1-48-35130 Wastewater Volume - Town of Blackf -108,769 -313,268 -1,215,500 -902,232 26

05-1-48-42100 Wastewater Volume - Septic Rec. St 0 0 -26,742 -26,742

05-1-48-55100 Interest Revenue -893 -2,205 0 2,205

05-1-48-85110 City of Lacombe Contributions 0 0 -261,968 -261,968

05-1-48-85130 Town of Blackfalds Contributions 0 0 -261,401 -261,401

05-1-48-85150 Lacombe County Contributions 0 0 -118,540 -118,540

REVENUES -338,340 -929,525 -4,327,261 -3,397,736 21

EXPENSES

05-2-48-13600 WCB 1,278 1,278 500 -778 256

05-2-48-21100 Travel & Subsistence 0 0 500 500

05-2-48-21400 Membership Fees 0 0 500 500

05-2-48-21500 Postage & Freight 112 112 156 44 72

05-2-48-21700 Telephone/Communications-Administr -2,066 0 1,540 1,540

05-2-48-21701 Telephone/Communications-Operation 4,228 7,064 29,916 22,852 24

05-2-48-21900 Testing (Sewage Strength Testing) 0 0 8,000 8,000

05-2-48-23000 Contracted Management Fees 0 1,450 24,000 22,550 6

05-2-48-23100 Accounting & Audit Fees 630 630 12,000 11,370 5

05-2-48-23200 Legal Fees 0 0 1,000 1,000

05-2-48-23900 Other Professional Services 4,600 4,600 20,000 15,400 23

05-2-48-25300 Parts & Repairs 496 1,493 10,000 8,507 15

05-2-48-25301 SCADA/Monitoring 0 0 20,000 20,000

05-2-48-26300 Equipment 0 273 1,200 927 23

05-2-48-27100 Licenses & Permits 0 0 1,000 1,000

05-2-48-27400 Insurance & Bond Premiums 0 0 47,000 47,000

05-2-48-34200 Administrative Costs 0 300 0 -300

05-2-48-35100 Treatment Charges City WWTP 211,116 554,896 2,152,123 1,597,227 26

05-2-48-35200 Operations Contract 29,982 89,946 359,784 269,838 25

05-2-48-35300 Septic Receiving Station-Op & Main 0 0 15,000 15,000

05-2-48-51000 Miscellaneous Expenses 2,860 2,860 5,000 2,140 57

05-2-48-51100 Meeting Supplies 363 363 0 -363

05-2-48-51400 Office Supplies 97 97 0 -97

05-2-48-52400 General Materials & Supplies 1,686 3,136 5,000 1,864 63

05-2-48-54100 Utilities - Water 828 2,496 5,400 2,904 46

05-2-48-54200 Utilities - Wastewater/Sewer 325 987 5,400 4,414 18

05-2-48-54300 Utilities - Natural Gas 4,476 10,356 30,000 19,644 35

05-2-48-54400 Utilities - Electric Power 60,060 82,117 228,000 145,883 36

05-2-48-56200 Chemicals 20,269 40,741 264,000 223,259 15

05-2-48-76100 Transfer to Operating Reserve 0 0 100,000 100,000

05-2-48-76200 Transfer to Capital Reserve 0 0 300,000 300,000

05-2-48-83100 Debenture Debt Interest 81,525 81,525 301,955 220,430 27

05-2-48-83200 Debenture Debt Principal 66,176 66,176 264,955 198,779 25

EXPENSES 489,041 952,897 4,213,929 3,261,032 23

23,372REGIONAL WASTEWATER REPORTING Total 150,701 -113,332 -136,704 21

Date: June 13th, 2019 Prepared by: Jordan Thompson Presented by: Jordan Thompson

DRAFT (Rev2): Tech Memo #18

sj v:\1139\active\113929319\07_reports_studies\tech memo's\18_techmemo#18-pump_operations\2. june 12 submission to nrd\mem_nrdrwwsc_techmemo#18_pump_operations_draft-rev2_2019-06-13.docx

To: Matthew Goudy, P.Eng. Jordan Thompson, CET., PMP.

From: Joel Sawatzky, P.Eng. Hoa Nguyen, P.Eng. Michael Magas, ME., CET.

NRDRWWSC Stantec

File: 113929319-07 Date: Original Draft – April 4, 2019 Revision 1 – May 14, 2019 Revision 2 – June 13, 2019

Reference: NRDRWWSC – Tech Memo #18: Pump Operations – Draft Rev 2

This Tech Memo summarizes the concerns found with the Sulzer pumps on the NRDRWWSC Lacombe Lift

Station since commissioning of the facility, the actions taken to date, and the recommended next steps.

1. BACKGROUND

On July 13, 2018 Stantec reviewed a reported concern with pump RSP-101 in the Lacombe Lift Station. The

pump was not completing its pump cycle, causing the PLC to shut it down and use the lag pump to finish the

pump cycle. Stantec then engaged Chandos (the Lift Station General Contractor) to perform troubleshooting

onsite starting on July 15, 2018.

On August 10, 2018 Stantec, Chandos, Tait (Chandos’ Electrical Subcontractor) and the NRDRWWSC

Operators were onsite to review this issue. During the review of RSP-101, it was also noticed that pump RSP-

103 was not performing as per design. After reviewing the pumping trends, it was discovered that, beginning

August 6, 2018, the discharge flow from pump RSP-103 was slowly decreasing.

On the morning of August 7, RSP-103’s discharge performance began to decline until the pump could no

longer discharge enough flow to open the downstream check valve, which occurred early in the morning of

August 9.

A second concern surfaced in February 2019 when one pump from each of Lacombe and Blackfalds stopped

working due to a motor fault. This memo will also summarize the analysis and findings for this concern.

2. INVESTIGATION AND ANALYSIS INTO THE CAUSE OF THE PUMP FAILURES AND EXCESSIVE VIBRATIONS:

A. Pump 103 Repair:

On August 14, 2018 representatives of Chandos, 3-Phase (the VFD/MCC Supplier), TDH (the Pump

Supplier), Schendel (the Mechanical Subcontractor) and Tait were onsite to fix pump RSP-101 by replacing

the relay and tightening a few noted loose cables. Pump RSP-103 was removed from the pump base in order

to inspect the impeller. It was discovered that the impeller had dropped, and the impeller bolt was missing

(and had most likely loosened and pumped down the line). The continuous operation of the pump with a

dropped impeller is also likely to have caused a noted crack in the impeller shaft. Pump RSP-103 was lifted to

the main floor of the Lift Station for Sulzer to pick up and bring to Sulzer’s facility in Edmonton for repairs.

Once RSP-103 was repaired in the factory, the pump was delivered to site. The pump was reinstalled on

October 29, 2018 and brought back into service on November 7 with TDH onsite to review the installation and

the pump startup.

June 13, 2019

Matthew Goudy, P.Eng. Jordan Thompson, CET., PMP.

Page 2 of 25


sjv:\1139\active\113929319\07_reports_studies\tech memo's\18_techmemo#18-pump_operations\2. june 12 submission to nrd\mem_nrdrwwsc_techmemo#18_pump_operations_draft-rev2_2019-06-13.docx

On November 3, it was discovered that pump RSP-101 was experiencing diminishing flows similar to what

had been previously observed with RSP-103. NRDRWWSC operators then turned off the pump, removing it

from service

B. Pump 101 Repair:

TDH and Scona (TDH’s electrical contractor) were onsite on November 7, 2018 and discovered that RSP-

101’s impeller fell, similar to what had previously occurred with RSP-103. In this instance though, the impeller

bolt sheared off instead of loosening and falling out. Sulzer decided it was best to take the pump to their

facility in Edmonton for full inspection and repair instead of just replacing the impeller and bolts on-site. At

their facility, Sulzer would be able to provide a full inspection of the impeller shaft for defects. Sulzer

concluded that it was best to completely rebuild Pump RSP-101, which included a replacement of the volute,

wear plate, mechanical seals, bearings and all O-rings.

Prior to failure, the run times for the various Lacombe Lift Station pumps were:

• RSP-101 = 578 hours

• RSP-102 = 833 hours (note that RSP-102’s run time continued to operate. The run time was recorded

when RSP-103 was re-commissioned)

• RSP-103 = 390 hours

On November 23, 2018 Sulzer, TDH, Stantec and the NRDRWWSC Operators measured vibrations from

Pump RSP-102 and RSP-103 in Lacombe and RSP-101 in Blackfalds. These results were compared to

subsequent test results to identify the effectiveness of mitigation measures taken.

RSP-101 in Lacombe Lift Station was re-installed on January 16, 2019 and the bump test was completed on

January 17, 2019 and the pump brought back into operation.

C. December 2018 Sulzer Report

Sulzer submitted a report on December 13, 2018, identifying possible causes for the damage to the impellers

to drop. These items included:

1. Dimensions of the pump bases: The dimensions of the pump bases were measured to be different

from the IFC drawings, and those installed at the Blackfalds Lift Station.

2. Poor concrete finish on the pump bases: From the surface, it can be seen that were cracks, holes and

gaps on the concrete of the pump bases.

3. Excessive vibrations: The vibrations for Pump RSP-101 and RSP-102 were higher than the factory

vibration testing, and higher than observed in the pumps at the Blackfalds Lift Station. Note that the

factory vibration testing is done under controlled conditions in a factory environment. The pump is

anchored and completely submerged, with the vibration test point at the top of the pump (motor). As

such, we expect to see higher vibrations in the field, and in a dry mount condition such as the

Lacombe and Blackfalds Lift Stations.

4. Suction pipe reducer and suction elbow: The suction reducer is installed adjacent to the pump, and in

Sulzer’s opinion, the pump elbow should be an extra-long radius elbow. Stantec has conducted a

June 13, 2019


Page 3 of 25



Computation Fluid Dynamics (CFD) model of the designed piping configuration and has concluded

that the reducer and suction elbow configuration is appropriate for the design flows and is not likely

the primary cause of the excessive vibrations.

Further discussion of the noted possible causes is included here.

D. Concrete Pump Bases and Concrete Finish

During construction, Stantec documented that the forms for the concrete pump bases needed to be revised to

meet the IFC design drawings. Unfortunately, this was not completed by the contractor on-site at the time.

Since the pump bases were installed smaller than noted in the Construction drawings, Clarification 016 was

provided to Chandos to improve all the concrete bases onsite. This clarification was sent to Chandos on

December 13, 2018. The requirements to modify the existing pump bases included dowelling into the existing

concrete base and roughing up the concrete. During Stantec’s review of the preparation and rebar

inspection, it was confirmed that the cracks, holes and gaps were superficial. The concrete underneath did

not pose a concern for the structure of the bases.

During the modifications of the pump bases, it was required that one pump always be operating with a second

pump on standby. Sulzer recommended preserving Lacombe Lift Station’s Pump RSP-102 as this was the

only pump that had the original factory components to compare with the findings from RSP-101 and RSP-103.

Stantec went onsite to reprogram the Lacombe Lift Station pumps to keep one pump as the ‘Lead’ pump,

while the other pump RSP-102 was set as the ‘Lag’ pump.

Following the direction from Stantec, Chandos and their subcontractors increased the size of the concrete

bases. The work on all the concrete pump base modifications at the Lacombe Lift Station were completed on

February 25, 2019.

E. CFD Modeling

As noted previously, Stantec’s CFD modeling concluded that the designed piping configuration would not

cause excessive vibrations due to the flow angle coming into the pumps. Moving the reducers further

upstream would be a design optimization that could be completed which might slightly improve the flow

dynamics for this station when one pump was running at full speed, however further investigation was

recommended prior to completing this modification. The swirl angle with one pump running was found to be

slightly above industry standard but still lower than what the manufacturer regards as “high swirl angles,”.

With two pumps running the velocities and resulting swirl angle were lower and well within industry standards.

Due to this, it was found that there shouldn’t be a concern that the reducer location would cause the pump

vibrations that were witnessed at high speeds. Regardless, the programming of the Lacombe lift station was

adjusted so that a single pump in operation will run at a lower speed, to a maximum of 50 Hz to limit the

excessive vibrations seen at higher speeds. This change does not impact the design pumping capacity of the

lift station as the programming will still allow two pumps to run full speed.

The CFD model analysis is attached for reference.

June 13, 2019


Page 4 of 25



F. January 28 Site Visit and Follow-Up

On January 28, 2019, a pump vibration and cavitation inspection were conducted by representatives from

Sulzer, TDH, Stantec and the NRDRWWSC Pumps RSP-102 and RSP-103 in the Lacombe LS were lifted to

review the impellers and bolts. The bolts for these two pumps were removed, inspected and, as a

precautionary measure, replaced with a new bolt and lock washer. There were no concerns with the bolts and

lock washers on RSP-102 and 103. The bolts were replaced to ensure that no future issues with the impeller

bolts are linked back to the old pump bases.

Similarly, the pump RSP-102 in the Blackfalds Lift Station was lifted and the bolt there was removed,

inspected and replaced as well. Again, we saw no concerns with this bolt and lock washer. We decided to

review the bolt and lock washer in Blackfalds as we want to verify a control test on a completely different

facility. With the bolt removed, it was deemed more appropriate to replace the bolt and lock washer as we had

it available.

From inspections, we noted no cavitation on any of the impellers in Blackfalds or Lacombe Lift Stations and

Sulzer confirmed this finding on-site. Further, we noted no defects or damage with the impeller bolts that were

removed.

Vibration testing was completed during this January 28, 2019 site visit by Sulzer and TDH through the

operational ranges of 40-45-50-55-60Hz. While the vibrations were reduced with the new Lacombe Lift

Station concrete pump bases between 40 and 50Hz, however the pumps did not perform as well under the

55-60Hz ranges as originally noted. It must be noted however that at this time, the improved base for RSP-

103 had not been completed, and that measured vibrations decreased near the concrete bases for the other

two pumps, suggesting that the enlarged concrete bases had a slight positive effect on the vibrations.

Conversely, the Blackfalds Lift Station pumps continued to perform well under all the operational ranges.

G. March 2019 Sulzer Report

Sulzer provided a power point format report on March 20, 2019, which indicated, in their opinion, the pumps

were likely not the cause of the excessive vibration. Sulzer pointed to a couple items with the piping

arrangement and supports at the station that could be improved to help lower the vibrations, and they are as

follows:

• A direct suction pipe to the pump with no common header;

• Additional support of the inflow pipe on concrete stands

• A long radius elbow coming into the pumps (note that this elbow was supplied by Sulzer, was

determined to be a medium radius elbow, and the CFD modeling did not indicate a problem with the

elbow).

• Inflow cone under the suction bell end in the wet well

While the pipe arrangement could be optimized as identified by Sulzer, the design will not allow for single

suction pipes to each pump as there are 3 duty pumps and 2 wet wells and this would limit the operational

flexibility of the lift station. Furthermore, the CFD model completed by Stantec indicates that smaller

optimization improvements along with the investigation of leveling the pumps (discussed below) may be the

solution to lower the vibrations.

June 13, 2019


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H. April Stantec Site Inspections

Don Munro was onsite on April 25 to review the pumps and piping alignment. During Don’s inspection of the

system, he noticed that the metal pump stands may not be completely level and the pipes may not align

completely straight into the pump’s elbow. We are working with the Contractor to confirm the metal pump

stand and piping alignment to verify if it meets Sulzer’s tolerances. Following confirmation of the tolerances

by Sulzer, Chandos will provide a 3D scan of the pump bases and work with millwrights to confirm the exact

pump stand alignment to verify if they meet the tolerances.

Subsequently, Dr. Fangbiao Lin and Liang Liu were onsite at the Lacombe LS on May 1 to review the

hydraulics of the system. They noted that hydraulically we do not think that the pipe configuration would

cause the vibration concerns witnessed in the Lacombe Lift Station. Observations on-site were that the

vibrations on the suction piping were significantly less than the vibrations on the discharge piping. As the

current pipe supports are one combined support for the two pipes, it was recommended to separate the single

support and provide an independent support for the discharge pipe. In addition, it was recommended to install

three additional pipe supports, one on the suction pipe and two on the discharge pipe to further stabilize the

pipes.

I. May Stantec Site Inspections

On May 14, Stantec was onsite to review the vibration and testing of the pumps with TDH. It was discovered

that there could be less than ideal wastewater flow dynamics in the wet wells that could be causing excessive

vibration in the pumps. The wastewater elevation that triggers a pump to start (pump start elevation) as well

as the pump stop elevation were raised by a meter for testing purposes and it was noticed that the pumps ran

a lot smoother after a couple pump cycles. Following this observation on-site, Stantec verified that the design

elevations (pump start and stop levels) meet and exceed the Sulzer recommendations (NPSHA = 9.3m;

NPSHR = 3.7m). Further investigation was carried out and it was found that the pump start and stop levels

could be raided without impact to the upstream piping, and this is a recommendation as noted later in the

memo.

On May 23 Stantec was onsite again to implement raising the wet well pump start and stop elevations to

temporarily improve the vibrations while a permanent solution was determined. However, while on-site it was

found that the H and HH back-up level bulbs could not be raised due to the conduit that was in place and this

has been noted as a warranty item for the contractor to correct. The Operators noted that they would prefer

the candy cane level instruments rather than the bulbs and we have looked into this as an optimization item.

On May 28, Stantec and an NRD Operator were on-site with the vibration meter (delivered on May 27) to test

the pump vibrations. It was found that the vibrations were between 4-9mm/s at different locations of pump

RSP-101 and RSP-103 at 80% (48 Hz) pump speed. It was also noted that during a pump cycle at a constant

80% speed the pumps ran rougher and louder for the first 1 minute and 20 seconds, after which the vibrations

and noise levels decreased for the remainder of the pump cycle. This was confirmed with both the vibration

meter and decibel reader. Stantec developed a spreadsheet to input data and allow for easy comparison of

the ongoing vibration testing results, and the operators have been sent this file for data input. Vibration tests

have been taken twice a week for the last 2 weeks and the vibrations are consistently under 9mm/s at 80%

speed.

June 13, 2019


Page 6 of 25



We have confirmed verbally with Sulzer on June 11 that the recommended vibration tolerance for the pumps

is 9mm/s, and our testing to date shows that the pumps are within the limits. Note, that vibration testing is

ongoing at various speeds and that data was not available at the time of writing.

We don’t have tangible evidence as to why the vibrations have recently lowered, however it appears that

temporarily raising the wet well level by one meter may have released air pockets in the piping and/or pumps

and allowed for improved priming of the pumps. Furthermore, the process configuration has been temporarily

modified (used only one wet well at the moment) and this may have also contributed to the improvements.

Further testing and investigation is required and is ongoing.

J. June Stantec Site Inspections

On June 5, Stantec was onsite to review the pump vibrations at various wet well level elevations to verify how

the level adjustments will impact the vibrations. The measurements from this testing show that the vibrations

are within limits of the 9mm/s verbal confirmation from Sulzer. We are still working with TDH to provide

written recommended vibration limit from the manufacturer.

Once more data is collected with the process configuration returned back to normal conditions, we will then

compile, compare and analyze the data in further detail and provide our findings to the Commission.

3. PUMP MOTOR FAILURE

A. February Stantec Site Inspections

The Blackfalds Lift Station pump RSP-101 produced an overcurrent fault on February 1. The Operators tried

to reset the fault and start the pump, but the same fault reoccurred. 3-Phase Power Systems was onsite to

review the VFD electrical data on February 8, 2019 and was able to pull the power data from the VFD.

However, they were not able to pinpoint the cause of the overcurrent fault at this site visit.

B. March Stantec Site Inspections

Subsequently, the Lacombe Lift Station had the same overcurrent issue on RSP-102 and the issue was noted

to the Contractor on March 6. On March 12, 3-Phase Power Systems came out to confirm if the issues were

similar in nature to the Blackfalds fault. Additionally, they attempted to run the pumps backwards in case

something was lodged in the impeller, however the pump failed to rotate backwards and Schendel was

engaged to lift the pump to verify if there was anything stuck in the impellers. It was found that there was no

clog in the pumps and the impellers moved freely.

TDH and Sulzer then wanted to verify the existing electrical conditions onsite prior to removing the pump from

the station. Two sets of electrical tests were conducted, and it was determined that the pumps needed to be

brought to a facility for further troubleshooting.

C. April Stantec Site Inspections

On April 15, 2019 the pumps from Lacombe and Blackfalds were removed from site and shipped to Edmonton

to an approved repair facility for analysis. As the delivery company did not make it to the Continental Group’s

facility in Edmonton prior to 4pm, they decided to store the pumps in their facility. While the delivery company

tried to remove the pumps off the truck bed, one pump fell on the other and both pumps fell off the truck.

June 13, 2019


Page 7 of 25



We’re still awaiting the incident report from the delivery company; however, it was determined that extensive

repairs were required to both pumps including the cooling jacket, lifting lug, volute, wear plate and bearings.

D. May Stantec Site Inspections

On May 17 Continental Group and Stantec were onsite to review and collect voltage and common mode

current data at motor input. This test was to determine the voltage spikes that the pumps are seeing on-site,

however only one of the pump/VFD circuits with pumps installed on-site were tested (P101), not the circuit of

P102 which is the pump that failed and is in the shop. The following is a summary and recommendation from

Continental Group.

• Testing was done at the motor terminal box to closely resemble the conditions within the motor;

• The ground voltage spikes were measured at 1200V, which Continental calculated to a value of

2078V for phase to phase;

• The measurements were taken from a pump that currently has no problems with the windings.

Continental indicated that it is possible that the failed pump could have seen higher voltage spike

levels and recommended that the test is conducted again once the pump is back in service.

• Continental also recommended to approach the VFD manufacturer to determine methods to lower

voltage spikes and recommended to communicate with the pump manufacturer to confirm the rating

of the windings, such that the inverter duty windings can withstand higher voltage peaks than the

measured 2078V.Additionally, they recommend measuring common mode currents present at the

motor. These currents can lead to damage to the bearings.

Stantec has reviewed the Continental report which pointed out that the actual circuits that saw the windings

fail were not tested and determined that further investigation of the VFD is required to provide a full picture of

the events that are happening onsite.

E. June Stantec Site Inspections

On June 7, Stantec, 3-Phase and Postma were onsite at the Lacombe Lift Station to test the peak-to-peak

and zero-to-peak voltage values at the output of the dv/dt filters on the two VFDs associated with the motor

failures. Measurements were taken for both peak-to-peak values and zero-to-peak values at the output of the

dV/dt filters of RSP-101 and RSP-102 (failed motor) as well as measurements of the peak-to-peak and zero-

to-peak values at the motor head of RSP-103, which was connected to VFD-102 (failed motor circuit).

For most of the testing, the meter was connected line-to-line, meaning that the main probe for channel A was

connected to the primary phase being measured and the secondary probe for that channel was connected to

an adjacent phase. This was to meet compliance with NEMA MG1, Part 31 for standards relating to inverter

duty motors.

June 13, 2019


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General Results:

At the output of the filters on the RSP-103/ VFD-102 configuration we generally measured:

o 2450V as a peak-to-peak value, line-to-line

o 1220V as a zero-to-peak value, line-to-line

• Both of these tests are within tolerance of the motors which should be able to withstand voltage

spikes of 1783V zero-to-peak, and is governed by the dV/dt filter at 150% the DC bus voltage √2 ∗600𝑉 ∗ 1.5 = 1273 𝑉𝑜𝑙𝑡𝑠.

When leads were connected at the motor in the RSP-103/ VFD-102 configuration we generally measured:

o 2800V to 3500V as a peak-to-peak value, line-to-line

o 1400V to 1900V as a zero-to-peak value, line-to-line

• In comparison to the tests above, the test results seen at the motors clearly show voltage spikes

slightly above the allowable limits according to the NEMA MG1, Part 31 ratings. Further investigation

as to what this means for the warranty coverage is still ongoing.

These same tests are scheduled to be completed at the Blackfalds Lift Station on June 13.

F. Pump Repair/Replacement Summary

There are two options to move forward with the two pumps that had a motor failure and fell off the truck:

1. Repair Two Original Pumps – At this time it is unknown if the motor failure is covered under

warranty, however Stantec is working with Chandos, Carrier Company Insurance, TDH, Sulzer,

Continental and 3-Phase Power Systems to verify the cause and confirm if the costs will be covered

under warranty.

• The order of magnitude cost for the repairs due to motor failure and truck incident are

$90,000 for Blackfalds and $100,000 for Lacombe.

• The timeline to repair the pumps would be 6-8 weeks from the approval to proceed.

• Once repaired, the warranty on these pumps would be 1-year full parts and labour from

Continental Group. We are currently investigating this to verify if the 5-year prorated the

Sulzer Warranty is also still valid.

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2. Order Two New Pumps - The other alternative is to order two new pumps with the total costs being

offset by the pending warranty repair of the pumps.

• The order of magnitude cost to purchase and install new pumps is as follows:

i. Blackfalds = $150,000 less the $90,000 for repair = $60,000

ii. Lacombe = $140,000 less the $100,000 for repair = $40,000

**These costs include $6,000 for a value-add built-in vibration monitor

** These costs DO NOT include installation, which is approximated at $10,000

• Therefore, the total cost to the Commission to purchase two new pumps, provided the

warranty claim is approved, would be in the order of $110,000.

• The timeline to order and install the new pumps would be 6-8 months from the approval to

proceed.

• The new pumps would come with Sulzer’s standard prorated 5 year warranty. There is an

option for the Commission to purchase a full 5 year parts and labour warranty at an additional

cost.

G. Back-up Plan for Lacombe Duty Pumps

With the Lacombe pump potentially being out of service for 2-8 months, it is a concern if another pump in

Lacombe were to fail leaving only one duty pump in the lift station. To prepare for such a scenario, we have

investigated the opportunity of using a pump from the Blackfalds LS and mount it onto the metal pump stand

in Lacombe and this has been confirmed to be a valid option in an emergency situation.

A second option is that TDH / Sulzer has 8” pumps that can be installed in Lacombe with some piping

modifications. This is a fall back plan and we don’t anticipate needing this option.

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4. RECOMMENDATIONS ON PATH FORWARD

A. Pump Vibrations

1. Pump Operations and Speeds Settings

The control narrative developed for the Blackfalds and Lacombe Lift Stations had the pumps start running at

full speed (60 Hz) and then gradually slow down to the normal operating speed set at 65% (39 Hz) and 68%

(41 Hz) respectively for Blackfalds and Lacombe. Through the investigation and analysis of the impellers and

vibration, significantly less vibrations occurred at 83% (50 Hz) than at 100% (60 Hz). Additional there was

slightly less vibrations running at 80% (48 Hz) when compared to less than 45 Hz. Therefore the pump

programming was modified to run at a maximum speed of 80% (48 Hz) then turned down to 67% (40 Hz)

through the pump cycle in both Blackfalds and at a constant 80% (48 Hz) in Lacombe.

The pumps are currently operating as follows. Blackfalds pumps are set as per the control narrative, and it is

recommended for these settings to remain in Lacombe until further investigation is carried out.

1. Blackfalds LS Pumps – Initial start at 80% (48 Hz) then lowered to 67% (40 Hz) through the pump

cycle.

2. Lacombe LS Pumps – A constant running speed of 80% (48 Hz) with one pump running, and 100%

(60 Hz) with two pumps running. Further vibration testing at various speeds will be completed to

confirm the optimal pump speeds.

Note: It is currently not recommended to run one pump in Lacombe higher than 83% (50 Hz).

If required, a second pump would kick on and with two pumps running, there is no expected

issue with running both pumps at 100% (60 Hz) as the velocities in both lines won’t be high

enough to cause vibrations significantly beyond those observed in factory testing.

2. Additional Vibration Monitoring / Inspections at Lacombe LS

It is recommended to preform periodic vibration monitoring of the pumps at the Lacombe LS to verify if the

vibration is worsening over time. The following vibration and inspection schedule is recommended to be

performed by the Commission Operators, with Stantec to support as required:

Date Activity

Vibration monitoring of all 3 duty

pumps at the 12 points completed

by Sulzer

Pull all 3 duty pumps and check

the impeller, impeller bolt and re-

torque as needed

July 2019 ✓ ✓

November 2019 ✓

February 2020

(FAC is July 31, 2020) ✓ ✓

January 2021 - 2025 Every year for 5 years

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Should the vibrations increase through the duration of these tests, a further investigation may be required.

Sulzer’s permanent real-time vibration sensor can be installed on the pumps, but Sulzer recommended that

the cost benefit of this option would not be practical, as the sensor would only monitor the vibration on top of

the pump, not at various points on the pump assembly and base.

There are multiple hand-held vibration testing kits available. TDH recommended a handheld vibration meter

with capital cost of approximately $3,500, could be sourced locally and left at the stations for the end user to

monitor vibrations. A more sensitive vibration sensor could be acquired, but for the purpose intended, we do

not recommend proceeding with the more expensive equipment. The handheld vibration meter was

purchased and awaiting delivery to site.

With the newly purchased handheld vibration meter, we recommend more frequent data readings early and

then level off afterwards at the Lacombe LS. With each testing, we recommended utilizing the free decibel

reader app on the phone. This will help visualize the amount of noise produced throughout the pump cycle.

A spreadsheet will be provided to the Operators to input the data and markings on the pump will provide

consistent measurement locations. The recommended testing is as follows for the Lacombe LS:

• Data entry for each active pump twice per week for two (2) weeks

• Data entry for each active pump once per week for two (2) weeks

• Data entry for each active pump twice per month for two (2) months

Other options, if desired in the future, are as follows:

• Install Sulzer’s stock vibration sensors – This would include removing the pump and shipping it to the

factory to remove the assembly, install the sensor, reassemble the pump and ship it back to site for

installation. Approximate cost is $20,000 per pump.

• Install continuous externally mounted vibration monitoring and connect the trends to SCADA - This

would allow pump shut down at extreme vibrations and monitoring of trends over time. TDH is

currently scoping out options for remote monitoring of the pumps but indicated that depending on the

option of simple or complete monitoring, it could range from $3,500-$20,000 for all 3 pumps.

3. Spare Parts for Lacombe LS

Currently there are spare parts onsite for a seal repair / rebuild, however no spare impeller or wear plate, both

of which were replaced when the bolt let go and the impeller dropped. Due to this, it is recommended to

procure at least one, preferably two hydraulic repair kits which consist of an impeller, wear plate and new bolt.

If additional impellers and wear plates are required in the future, they are approximately 6-10 weeks for

delivery. Should the shaft break or inspection of the shaft be warranted due to vibrations or lower flows, the

pump will need to be brought to Sulzer’s facility for further investigation.

We also confirmed with Sulzer that the Impellers are the same for both Lacombe and Blackfalds with the

exception of the trim. Therefore, the impellers could be used at the Blackfalds LS in an emergency but would

produce slightly less flow (~10-20%) than the current Blackfalds impellers. The wear plates and bolts are the

same at both Lacombe and Blackfalds and can be used interchangeably.

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Blackfalds LS Lacombe LS

Currently Provided Spare Parts Currently Provided Spare Parts

One (1) repair kit for the submersible pump; One (1) repair kit for the submersible pump;

One (1) repair kit for the sump pump; One (1) repair kit for the emergency pump;

One (1) repair kit for the sump pump;

Recommended Additional Spare Parts Recommended Additional Spare Parts

The impeller for Lacombe is slightly smaller

than Blackfalds. It is recommended to use the

Lacombe hydraulic repair kit if needed.

One (1) hydraulic repair kit for the

submersible pumps - $12,000

The existing repair kits are comprised of:

➢ All o-rings for the pump

➢ All mechanical seals

➢ All bearings

➢ Other hardware that needs to be replaced when taking apart the pump, including some

screws and washers.

The new hydraulic repair kit is comprised of:

➢ Impeller

➢ Wear plate

➢ Impeller bolt with locking hardware

4. Extended Pump Warranty

We have formally requested that an extended warranty be provided by Sulzer for the pumps at both the

Blackfalds and Lacombe lift stations.

TDH indicated that for them to approach the Sulzer factory with a request of a warranty extension, the

vibration needs to be reduced. With the current vibration, the factory would currently reject the request.

Once the vibrations are lowered, there are three (3) possibilities that would occur:

1. Rejection of warranty extension;

2. Approval of extended warranty with no costs associated; or,

3. Approval of extended warranty with costs associated.

With this, there is currently no guarantee that an extended warranty will be provided by Sulzer.

The costs for a full 5-year full municipal warranty, based on information provided during the pump selection

process, would cost roughly $21,500 per unit, or $64,500 for the 3 pumps in Lacombe.

Attached is the full 2-year with a 5-year pro-rated warranty provided with the Sulzer pumps. The start-up date

for Lacombe was completed on February 23, 2018.

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4. Concrete Pump Bases

The concrete pump bases were originally installed to Sulzer specifications; however this was smaller than the

design details. As a recommendation from Sulzer, the pump bases were increased in size to exceed the

design detail requirements, and this added strength and mass to the pump bases to provide a more stable

footing. The upgrade was completed a no cost to the NRDRWWSC.

5. Pipe Supports on Suction and Discharge Piping

Sulzer has recommended possible pipe and pipe support modifications to possibly further reduce the pump

vibrations. These optimization improvements could provide incremental improvements to the observed

vibrations, and we have reviewed various options noted above, and from the site visit by our senior process

engineer Liang Liu, and our senior hydraulic modeler Dr. Fangbiao Lin, it was observed that the discharge

pipe in Lacombe vibrates a lot more than the suction pipe, and together with the Sulzer recommendation for

additional pipe supports, it was determined to proceed with the following enhancements:

• Remove the common pipe support on the suction and discharge pipes and have it be an independent

support on the discharge pipe.

• Add an additional three metal pipe supports, one on the suction pipe and two on the discharge pipe.

The approximate cost to compete the additional pipe supports is $20,000 for the three duty pumps.

This item was approved in the May 21 Board meeting and the pipe supports are being manufactured will be

installed by the end of July. The long delay is due to the galvanization process.

5. Wet Well Optimization

The following items are considerations to implement inside both wet wells in the Lacombe LS based on

information that we have gathered to date. By completing these wet well optimization items, we feel this will

further reduce vibrations and prevent the risks of it returning in the future. However, further investigation is

ongoing and the considerations for improvement may change.

1. Wet Well Cleaning and Safe Entry to Complete the Work

• We recommended completing the following optimization items at the same time as the wet

well requires cleaning and confined space entry. The safety confined space entry monitoring

costs approximately $3,500 per day. Best case the work will be completed in one (1) day for

each cell, with a conservative estimate of three (3) days per cell, resulting in costs of $7,000

to $21,000. Additionally, the Contractor estimated between $8,000 and $20,000 to clean both

wet well cells as they were not able to visit the site prior to providing the estimate.

• The estimated total cost to clean the wet well cells and provide safe entry for the work is

between $15,000 and $41,000.

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2. Hydro Cones (one under each suction intake)

• Hydro cones are sometimes installed under each intake to allow for a more uniform flow into

the suction piping system, however it is typically not necessary, and the vast majority of lift

stations designed by Stantec in Alberta do not have hydro cones installed. The cones help to

reduce the turbulence in the wastewater that could cause vibrations in both piping and

pumps. Stantec has approached the Contractor for a cost to install two stainless steel hydro

cones, one for each intake. This work involves entering the tank to bolt the cones onto the

floor and does not include the wet well cleaning and safe entry procedures and costs noted

above. The cost to do this work is approximately $8,000.

3. Removal of Concrete Flow Diversion Structure in the both Wet Wells

• As modelled by the CFD model, removing the flow diversion structures will improve the flow

patterns in the wet well and help to reduce the swirls inside the wet wells. This would in turn

allow a more laminar flow into the suction piping. Additionally, sludge may accumulate on the

other side of the diversion structure which is not ideal. This work involves cutting out the

concrete structures, coating the exposed rebar and re-applying a new corrosion resistant liner

on the exposed concrete. The estimated cost to demolish and re-coat the concrete is

$20,000.

4. Wet Well Pumping Elevations

• It is beneficial to keep the volute and impeller of the pumps fully submerged. During the

pump down phase of the Lacombe pumps, the pump gradually slows to a stop once the

command to stop the pump is initiated. This causes the water level in the wet wells to fall

slightly below the top of the volute. As such, Stantec is confirming the site conditions to

possibly raise the pumping start and stop elevations to allow for more head pressure in the

wet wells. We anticipate raising the wet well levels by approximately 300-500mm. This work

wil be completed at no cost to the NRDRWWSC.

The cost to complete the recommended wet well optimization work is between $40,000 and $70,000

As an optional value-added item, the Operators have suggested we look at installing ‘candy cane’ level

sensors in place of the level bulbs for reduced maintenance and improved reliability of the back-up level

sensors. The estimated cost for this work is $10,000.

6. Suction Piping Pressure Gauge

It was noted in a May site investigation that the suction pressures should be monitored to verify that we do not

have negative pressures coming into the pumps, and for periodic monitoring of this. As we wanted to move

quickly with this small cost item, this work was initiated and has been completed as of June 10. The cost for

this work came out to approximately $3,700 and this cost is included in the recommendations for approval

below.

Stantec and the Contractor will take readings at each site visit and will take a video of the gauges for a full

pump cycle. It is recommended that the Operators monitor these gauges as a part of their regular checks.

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B. Pump Motor Failures

7. Pump Motor Failure - Repair versus New Pumps

There are two options to move forward with the two pumps that had a motor failure and fell off the truck:

1. Repair Two Original Pumps

• The order of magnitude cost for the repairs due to motor failure and truck incident are

$90,000 for Blackfalds and $100,000 for Lacombe.

• The timeline to repair the pumps would be 6-8 weeks from the approval to proceed.

• Once repaired, the warranty on these pumps would be 1-year full parts and labour from

Continental Group.

2. Order Two New Pumps

• The order of magnitude cost to purchase and install new pumps is as follows:

i. Blackfalds = $150,000 less the $90,000 for repair = $60,000 + $5,000 for install

ii. Lacombe = $140,000 less the $100,000 for repair = $40,000 + $5,000 for install

• The timeline to order and install the new pumps would be 6-8 months from the approval to

proceed.

• The new pumps would come with Sulzer’s standard prorated 5-year warranty. There is an

option for the Commission to purchase a full 5-year parts and labour warranty at an additional

cost.

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5. ELECTRICAL NEXT STEPS

A. Installation Adjustments

1. Reconfigure Cables

The cables for each pump currently travel through a ladder-style tray system in the pump gallery and are then

routed to the VFDs on the main level through a series of vertical metal conduits designed to protect the cable

from mechanical damage while allowing the cables to be installed and removed easily. The cables were

originally spaced with airgaps between each conductor to prevent overheating. After further calculations for

amperage capacity on the existing pump cables, it is determined that the air gaps are not required for heat

dissipation on the cables. Considering the amount of electrical “noise” that has been observed through the

cabling of the tested pumps, it is recommended that the cables be removed for each pump and reconfigured

so that all motor leads are bunched together in the tray and are routed to each VFD through a single conduit

(per pump).

The spacing of the cable in the tray below the conduits is standard practice to ensure that the cables can

dissipate heat adequately. It would then make sense in the original install that each cable would have it’s own

conduit. After further research, running single phase cable alone in metallic conduits may cause magnetic

interference. Putting all the cables (one cable per phase) in one conduit would cancel out the magnetic fields

between the phases and in theory lower the interference. The conduits have all been grounded so it’s not

entirely known if this is part of the problem, however eliminating it as a contributor is prudent.

Calculations showing the cable capacity are below:

• Cables are 262MCM

• Cables are rated at 471amps @30DegC ▪ Correction factor for 75deg – 425amps ▪ Correction factor for running all cable together is 0.85 ▪ Cables are good to 340amps ▪ VFDs state they are using 201amps ▪ Pumps are rated at 324 amps ▪ Cables should be bunched together on tray and in one conduit

2. Lower Voltage from Utility at Each Site

The electrical utility supplies power to the site through a primary transformer with a secondary (site) voltage of

600volts nominal. Under Canadian guidelines, the supplied voltage to the site is restricted to variances and

fluctuations to within 5% of the nominal voltage allowing the supplied voltage to vary between 570V to 630V.

The measured incoming voltage on the Lacombe site was documented at 620volts. While this level is within

the allowable 5% of the nominal voltage, it was presumed that the higher than normal site voltage is raising

the DC bus voltage of the VFDs to almost 880volts DC. This phenomenon is not considered as affecting the

output of the VFDs (which was observed at 825VDC as a constant output when pumps are running) but will

aid in ensuring that any fluctuations on the utility side will not cause the supplied site voltage to rise above the

allowable variance for short periods of time.

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Lowering the voltage on site can be achieved by engaging Fortis and requesting that they “turn down” the

voltage taps on the utility transformer. The service is offered through Fortis field service. An electrical

representative for the Commission is recommended to be onsite at the time of the adjustment to verify the

results in the building and recommend further changes if required.

3. Repair Grounding Issues

During the testing efforts at the Lacombe lift station, inspections of the grounding system were conducted.

Stantec found that the grounding of the pump cables through the MCC system were not adequate. It was

apparent that the grounding cables for feeders to the VFDs were cut short in the cabinets and then grounded

to the frame of the MCC rather than returning the grounding properly to the ground bar of the MCC, located at

the bottom of each section.

It is recommended that the grounding issues are remedied as soon as possible. While the current grounding

does not directly relate to some of the other pump issues found on site, it is required to be done properly to

ensure that nuisance problems that are hard to trace and troubleshoot are not complicating the testing and

more importantly the overall performance of the pumps. Remedial action must include:

1. All grounding of equipment must return to the appropriate grounding bars.

2. Recommendation is for a full review of the grounding system by third party and the engineer

prior to remediation and after to confirm code compliance and design intent.

3. All remaining pumps shall be fully tested electrically (resistance, insulation and surge) and

health of equipment documented.

Figure 11/12: Grounding to be repaired: typical for all pumps in Lacombe

Figure 11 Figure 12

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B. Equipment for Monitoring and Mitigation

1. Power Monitoring from Utility to VFDs

It has been noted that utility power in Lacombe can fluctuate. While lowering the supply voltage at the site will

aid in ensuring that any fluctuations in the utility do not surpass the 5% allowable threshold, it is also

recommended that utility-grade monitoring be installed on the MCC to allow the client to monitor utility events

through the existing SCADA system. This would give the Commission historical data to refer to should other

event occur in the future, and it would allow alarms to be created and notify operations when power supply

parameters are not being met.

There are several options to consider for monitoring power.

1. Utility-grade power monitors: cost estimated at $35,000 per site x 2 = $70,000

• Utility grade power monitoring would allow the Commission to track all typical values

including voltage, current, and power factor. It would also allow the commission to track

voltage transients (dirty power events such as loss of phase, voltage surges and spikes) and

also track peak voltages.

2. Temporary power monitors and reporting: cost estimated at $15,000 per site x 2 = $30,000

• This effort would include the rental and installation of portable monitoring equipment for a

determined period of time and log data gathered by the instrumentation for future analysis.

This data can be retrieved, interpreted and reported on to the Commission through Stantec,

by a professional electrical contractor or through other 3rd party provider.

3. Use of existing power meters with connections to the PLC: cost estimated at $7,000 per site x 2 =

$14,000

• This effort would include engagement of an electrical firm to connect the existing power

monitoring equipment in the site Automatic Transfer Switch to the site PLC to post data to the

existing SCADA system. The existing power monitoring equipment cannot provide the same

level of detail in monitoring incoming power conditions as utility-grade metering systems,

therefore the data that will be collected for analytics will be limited and basic compared to

other options.

2. Power Monitoring from VFDs to Motors

The ground fault relays monitor the circuit for conditions that would suggest that a ground fault would be

imminent. The systems are much more sensitive than the monitoring function of the VFD system and can

detect an incident prior to it causing permanent damage to the motors.

• Additionally, the relays can test the motor and cable insulation and log the data. The testing is

accomplished by isolating the circuit and then performing the tests with the relay system. The

resulting data can then be analyzed for degradation to motor or cable isolation over time. This

provides the owner with valuable analytics that can be used for preventative maintenance

purposes.

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3. Replace dV/dt Filters with Sinus Filters

Standard installation for VFD filtration is dV/dt filters. Additional equipment can be added to the VFD and

motor assemblies to further reduce the voltage spikes seen at the motors in an effort to prolong the motors

and motor winding insulation from breakdown. While these options were considered during the design of

the system, the additional equipment required is expensive and is not typically installed as a standard

practice unless specific conditions for the combination of motors and VFDs are met. These outlier

conditions include excessive motor cable lengths up to 300 meters between the drive and the motor, non-

inverter duty rated motors on variable speed drives, motors in wet locations or motors with alternate insulation

classes other than those specified for drives under NEMA MG1, Part 31.

Given the specific circumstances now experienced on both the Lacombe and Blackfalds sites, the following

equipment are considerations for improved power conditioning and additional monitoring of the motors.

• The Sinus (or Sine) filters remove virtually all of the VFD’s entire switching frequency

component. The end result is a relatively clean sine wave voltage waveform at the motor

terminals. Its purpose is to reduce VFD generated acoustic noise at the motor and to reduce

motor insulation stress.

• The systems have been recommended by Sulzer and by 3Phase for installation as a

mitigation tool for motor “noise” as found on site.

• The image below shows voltage and current waveforms without a filter, with a dv/dt filter, and

with a sinus filter from left to right respectively. Voltage waveforms are displayed on the top

graphs while current is presented on the bottom.

Figure 13: Sine wave correction

June 13, 2019


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C. Equipment Verification

1. Pump Motors

At this time, Stantec continues to request information from Sulzer to verify the exact build specifications for

the motors installed. Sulzer has recommended that new motor nameplates be installed on the motors, this

time with CSA certifications. It is uncertain what information will be presented on the new nameplates

however the discrepancies as found on the existing nameplates include:

• CSA certification was missing when they were marked as provided within the reviewed shop drawings.

• FM approvals were provided which indicates that the motors were intended for the US market.

• CE standards are present on the nameplates along with approvals for Hazardous, Class 1, Div 1,

Groups C&D locations.

• Sensors installed in the motors are bi-metal temperature switches, while optional thermistor/ RTD

devices were not selected in the shop drawings.

While the pumps are not required to run in a hazardous atmosphere, the presence of the CE certifications

(European Safety Standards) along with the certifications for hazardous locations suggest that these pumps

are certified to run in Hazardous atmospheres. Sulzer’s Installation and Operations Manual (2015 and 2019)

both comment that if pumps are to operate in hazardous atmospheres while on inverter drives, the PTC

(thermistor) sensors must be present. As these specific pumps were supplied with bi-metal temperature

switches rather than thermistors for temperature monitoring, it is unclear at this time if the pumps were

intended to be used on VFD systems.

The recommendation at this time is for Stantec to continue conversations with Sulzer and insist on build

sheets for each of the motors in relation to the manufactures serial numbers for comparison of VFD and non-

VFD rated systems provided by Sulzer.

2. MTE dV/dt Filters

In reference to the information provided above on Page 19, the dV/dt filters are specified for performance up

to a cable length of 1000 feet between the filter and the drive, to lower and maintain the peak voltage spikes

within the assembly to 150% of the DC bus voltage. Assuming the use of the running DC bus voltage of 825V,

the expected peak voltage is roughly √2 ∗ 600𝑉 ∗ 1.05 ∗ 1.5 = 1336 𝑉𝑜𝑙𝑡𝑠. The cables specified in the design

were to be equal or less than 30 meters (less than 100feet). Considering that the peak voltage observed

during testing was between 1400V and 1800V, and that the cables are no more than 100ft between the filter

(drive) and the motor, it is unclear at this time if the filters are within specification.

The recommendation at this time is for Stantec to continue conversations with 3Phase for further information on the specification of the dV/dt filters and their exceptions. A possible outcome may be a recommendation for a change to shielded feeder cable to the motors, or a re-specification of the dV/dt filters.

3. Install PTCs (PTC DIN 44082)

As required by Sulzer, PTCs need to be used with any pump being operated with a VFD. PTCs provide a way

to measure the temperature of the windings at any given time. This gives us the ability to note and flag any

rapid increases in temperature. Bi-metallic switches are currently being used which are strictly digital and only

provide an on/off signal. Sulzer has stated that they are confident the sensors installed will meet the

requirements, however their documentation say otherwise. We are continuing to challenge Sulzer on this.

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6. SUMMARY OF RECOMMENDATIONS FOR COMMISSION APPROVAL

A. Pump Vibrations

Currently the Lacombe pumps are operating within the manufactures specifications of 9mm/s for vibrations at

the 50 Hz pump speed. Further testing is ongoing at various pump speeds for the full pump cycle to verify if

all pumps speeds on the two operating duty pumps are within the 9mm/s vibration tolerance. We don’t have

tangible evidence as to why the vibrations have recently lowered, however it appears that temporarily raising

the wet well level by one meter may have released air pockets in the piping and/or pumps and allowed for

improved priming of the pumps.

It has also been identified that flow profile improvements in the wet well may further help to reduce pump

vibrations and reduce the risk of it coming back in the future. Although we are unsure at this time if these

items are the root cause, our process specialist has identified that they should help improve the flow profile

and therefore help to minimum vibrations.

The pumps are currently operating within specification; however, this is with process modifications

(using only one wet well), and therefore it is an option to wait on these improvements for further

investigation and vibration results.

1. Vibration Monitoring Equipment

a. Completed

b. Cost to NRD = $3,000

2. Spare Parts

a. Completed

b. Cost to NRD = $13,000

3. Concrete Pump Bases

a. Completed

b. Cost to NRD = $0

4. Pipe Supports on Suction and Discharge Piping

a. Approved at the May 21 Board Meeting. It is anticipated that these pipe supports will be installed by

the end of July.

b. Cost Estimate to NRD = $20,000

5. Suction Piping Pressure Gauges

a. Completed

b. Cost Estimate to NRD = $4,000

June 13, 2019


Page 22 of 25



6. Wet Well Modifications

The recommended wet well improvements noted below have been identified as the best solutions

with the information to date, however at this point, it is an option to hold off on implementing the

improvements until more data is collected.

The following work is recommended to be completed in the wet well to further reduce the swirls in the wet

wells and provide a more laminar flow into the pumps. It is recommended to complete the following

modifications at the same time to share the costs of cleaning and monitoring for confined space entry.

a. Wet Well Cleaning and Safe Entry

i. Estimated Cost to NRD is between $15,000 and $41,000

b. Hydro Cones Under the Suction Bell Ends

i. Hydro cones are installed underneath the bell suction to allow for a more direct flow

into the pipes. This works involves entering the wet wells and bolting an SS cone to

the floor.

ii. Cost Estimate to NRD = $8,000

c. Removal of the Concrete Flow Diversion Structures

i. The concrete flow diversion structures in the wet wells are installed to direct flows

into each bell suction. With one intake in each wet well at the Lacombe LS, the

diversion structure is not required. With the CFD model, it shows that removing the

diversion structure will theoretically reduce the swirls inside the wet wells and provide

a laminar flow into the piping system.

ii. Cost Estimate to NRD = $20,000

d. Raising the Wet Well Pump Start and Stop Levels

i. Site investigations have determined that raising the wet well levels will not impact the

upstream piping and will assist with the flow dynamics in the wet well.

ii. Cost Estimate to NRD = $0 (Warranty Item)

The cost to complete the recommended wet well optimization work is between $40,000 and $70,000

The total recommended cost for the pump vibration mitigation measures is $110,000 upset limit (of

which $36,000 has already been approved).

June 13, 2019


Page 23 of 25



B. Motor Failures

The recommended electrical improvements noted below have been identified as the best solutions

with the information to date, however at this point, it is an option to hold off on implementing the

improvements until more data is collected. We will, however, engage the contractor immediately for

completion of the warranty items.

1. Reconfigure Cables

• It is recommended that the cables be removed for each pump and reconfigured so that all motor

leads are bunched together in the tray and are routed to each VFD through a single conduit (per

pump).

• Cost Estimate to NRD = $6,000

2. Lower Voltage from Utility at Each Site

• It is recommended that the Utility provider (Fortis) be engaged to lower the site voltages by turning

down the tap system within the site utility transformer. This effort must be done in coordination with

the Utility provider for access to the site transformer and with an engineering representative for

evaluation of the turn down results.

• Cost Estimate to NRD = $0 (Warranty Item)

3. Repair Grounding Issues

• It is recommended that the grounding issues are remedied as soon as possible. While the current

grounding does not directly relate to some of the other pump issues found on site, it is required to

be done properly to ensure that nuisance problems that are hard to trace and troubleshoot are not

complicating the testing and more importantly the overall performance of the pumps.

• Cost Estimate to NRD = $0 (Warranty item for Lacombe; not required in Blackfalds)

4. Power Monitoring from Utility to VFDs

It is recommended that utility-grade monitoring be installed on the MCC to allow monitoring of utility events.

There are several options to consider for monitoring power, as follows:

a. Utility-grade power monitors:

• Cost estimated at $40,000 per site x 2 sites = $80,000

• Allow tracking of all typical values including voltage, current, and power factor as well as

voltage transients (voltage surges and spikes), loss of phase and peak voltages.

b. Temporary power monitors and reporting:


• Rental and installation of temporary equipment. Data logging for an extended period of time

(suggest 1 month minimum), analysis and reporting of outcomes

June 13, 2019


Page 24 of 25



c. Use of existing power meters with connections to the PLC:


• Connection of existing equipment to the PLC for monitoring of simple events. Items such as

voltage transients, loss of phase and peak voltages are not provided.

5. Power Monitoring from VFDs to Motors

Monitoring the power to the motors after the VFDs is a complicated issue because at that point, the voltage and current going to the pumps are not sinusoidal as clean AC power would be. The instrumentation tuned to monitor power on non-sinusoidal forms is limited and ground fault relays monitor the circuit for conditions that would suggest that a ground fault would be imminent. The system is much more sensitive than the monitoring function of the VFD system and can detect an incident prior to it causing permanent damage to the motors.

• Install Ground Fault Relay Technology: Estimated cost is $8,000 per pump x 8 pumps = $64,000

6. Replace dV/dt Filters with Sinus Filters

Given the specific circumstances now experienced on both the Lacombe and Blackfalds sites, the following

equipment are considerations for improved power conditioning and additional monitoring of the motors.

• Installation of Sinus Filtering: Estimated cost is $25,000 per pump x 8 pumps = $200,000.

The Sinus filters would replace the existing dV/dt filters in the VFD cabinets. The filters are physically larger

than the dV/dt filters and will therefore need to be mounted above the MCC for appropriate ventilation.

The total recommended cost for the pump electrical items is $270,000 + power monitoring ($14-$80k).

June 13, 2019


Page 25 of 25



7. CONCLUSION

The investigations have been ongoing for many months to solve both the pump vibration and pump motor

failure concerns, and the Contractor, Suppliers, and Stantec have put in a considerable amount of time and

effort to solve these concerns. We are working towards a solution to provide a fully functioning system for

long term reliable wastewater conveyance from Lacombe to Red Deer. For this to happen, we are

recommending various upgrades and optimization items of which some are highly recommended, and others

are more optional value-add items. We understand that these costs for modifications and optimization will be

covered under the 90/10 Water for Life grant program and we have confirmed with Alberta Transportation that

the project grant is still open with available funds. We will work to minimize the costs for the approved items

as much as possible. Stantec is invested in this project and will not charge for our services to resolve the

pump vibration concerns.

Blackfalds Lift Station

With the site review for vibrations and inspection of the impellers, there were no concerns with the pump

vibrations at the Blackfalds Lift Station. There was no excessive vibration though the pump ranges and no

cavitation witnessed on the impellers or suction elbows.

The investigation with the motor failure is ongoing and a site visit is scheduled for June 13 to perform further

testing on the electrical systems from the VDF’s to the pumps.

Lacombe Lift Station

The Lacombe Lift Station pumps currently have two separate concerns, pump vibrations and motor fault. It

has been noticed that the pump vibrations have been reduced and we will continue to monitor this utilizing the

vibration meter to take regular measurements. Further optimization items are being implemented to reduce

the risks of the excess vibrations returning.

Similar to the Blackfalds, the investigation on the motor failure is ongoing. We will compare that data between

the two sites after the electrical testing is completed at Blackfalds on June 13.

We trust that this memo outlines the history of the Lacombe Lift Station pumps and provides recommended

next steps to ensure that the NRDRWWSC has confidence in the pumps to provide reliable operation for

many years into the future.

Sincerely,

Stantec Consulting Ltd.

Joel Sawatzky, P.Eng. Project Manager Phone: 403-341-3320

[email protected]

Hoa Nguyen, P.Eng. Resident Engineer Phone: 403 356 3282

[email protected]

Michael Magas, ME., CET.

Master Electrician Phone: 403 341 3320 [email protected]

mailto:[email protected]

02468

Alberta One-Call Locate Requests

2018

2019

Engineer’s Report - Stantec June 10, 2019 North Red Deer Regional Wastewater Services Commission – Engineer’s Report

sj v:\1139\active\113929319\07_reports_studies\engineer's reports\2019\eng_report_nrdrwwsc_2019_06-10.docx

Engineer’s Report June 10, 2019

North Red Deer Regional Wastewater Services Commission

(NRDRWWSC)

Submitted to: North Red Deer Regional Wastewater Services Commission Matt Goudy, P.Eng. – CAO Jordan Thompson, CET, PMP – Assistant CAO

Submitted by: Stantec Consulting Ltd. - Red Deer

Per: Todd Simenson, P.Eng. Joel Sawatzky, P.Eng.

FILE 113929319

1. Construction Progress

a) The construction of the regional system is complete. Remaining work pertains to small clean-up of seasonal deficiencies at the three facilities and completion of the equalization storage facilities.

b) The Construction Completion Certificates (CCCs) have been

approved for Contracts 1, 3, 5, and 6. Contract 2 CCC will be issued once the stairs are complete (railing deficiency still outstanding). While Contract 4 CCC will be issued once the lagoon work is completed this year. O&M Manuals and Plan of Record drawings are complete and submitted for all Contracts 1 through 6.



2. Equalization Storage Completion

a) Blackfalds • Blackfalds Lagoon desludging is complete. Contractor is

moving clay to shape the berms. • The remaining work including planting trees, placing topsoil

and seeing, riprap the inlet pipes will be completed by June 30.

b) Lacombe • Desludging in Lacombe is complete. • The piping connecting the cells c/w rip rap placement at the

pipe ends, final grading, topsoil placement and seeding will be completed by June 30.

3. Deficiency Clean-up

a) General

• Operator’s 6-months’ training for Biorem, Envent and the

camera security system is scheduled for June 26.

b) OMF • The Biofilter access stairs are nearly complete but still require

the removable handrails and concrete pads at the stair landings.

• Currently awaiting engineering stamped drawings for the modified removable rails from galvanized steel to aluminum, as the weight of the steel prevent the Operators from removing the handrails. The Contractor indicated that the drawings should be stamped this week and they anticipate the deficiencies on the stairs will be rectified by late June or early July.

• The deficient leaking dampers have been replaced.

c) Blackfalds LS • The perimeter fencing and final site gravels will be completed

by July 15.

• Pump Motor Failure: See the Lacombe LS update for the latest information.



d) Lacombe LS • A few seasonal deficiencies are still remaining, including

damp concrete in the dry well and seeding near the fences.

• Pump Vibrations

• Pipe supports as approved at the May 21 Board

meeting are being fabricated and due to galvanizing will be installed in July.

• Pump vibrations have decreased over the last month to be within the 9mm/s Sulzer specified requirements, however, there have been process modifications done (using only one wet well cell and one valve is closed) and therefore further investigation is required prior to implementing the recommended wet well modifications.

• Pump Motor Failure:

• Pump RSP-101 is in the shop for repair of the windings which overheated. The cause and warranty repair confirmation are still under investigation, however at this time it is believed to be from voltage spikes between the VDF and pumps (not from the incoming power source).

• The latest investigation on-site on June 8 has

unofficially determined that the voltage out of the VFD are within spec but the voltage at the pumps are above spec.

• We are continuing to investigate this at both

Lacombe and Blackfalds to find the root cause, including an all-day investigation of Blackfalds pumps on June 13.

• Further information will be provided when available.



e) Pipeline • There is minor work required to improve the drainage on Bill

Brannen’s land and Hamm Construction is engaged and is working on this. A meeting onsite with Hamm, the Town and Stantec to discuss a plan to move forward is scheduled for June 13.

4. Summary of Project Balance – Engineering, Construction, and Land

Reference update from Justin de Bresser. If needed, the summary of project balance will be updated later in May to provide an update at the next meeting.



5. Reference Photos: Contract 6: Lacombe LS

Figure 1: Operators using vibration meter



Contract 6: Lacombe LS

Figure 2: Vibration of the Lacombe pumps has decreased.



Contract 6: Lacombe Lagoons

Figure 3: Stantec verifying the levelness of the pump bases




Figure 4: Sub-contractor measuring out dimensions for the enhanced pipe supports




Figure 5: Piping in the Lacombe Lagoons

Summary of Final Project Costs Updated January 31, 2019

Account Name ContractG

LContract Budget

Value of Work to

January 31, 2019

Current Estimate

to Complete

Estimated Final

Total

Remaining

Budget

General Supplies -$ 70,367.00$ -$ 70,367.00$ (70,367.00)$ *

Engineering, Specialty Services and Sub-Consultants 7,793,680.66$ 7,723,789.44$ 47,000.00$ 7,770,789.44$ 22,891.22$

Engineering / Construct. Contract 1 - Whissell 8,490,892.50$ 8,439,336.82$ -$ 8,439,336.82$ 51,555.68$

Engineering / Construct. Contract 2 - Alpha 4,420,952.22$ 3,976,950.57$ 221,862.75$ 4,198,813.32$ 222,138.90$

Engineering / Construct. Contract 3 - Pidherney's 11,688,183.40$ 11,448,881.23$ -$ 11,448,881.23$ 239,302.17$

Engineering / Construct. Contract 4 - Alpha 11,776,190.07$ 10,398,617.19$ 1,212,165.62$ 11,610,782.81$ 165,407.26$

Engineering / Construct. Contract 5 - Hamm 16,886,676.72$ 16,587,923.98$ -$ 16,587,923.98$ 298,752.74$

Engineering / Construct. Contract 6 - Chandos 6,989,337.40$ 6,907,796.44$ -$ 6,907,796.44$ 81,540.96$

Project Management -$ 58,823.00$ -$ 58,823.00$ (58,823.00)$ *

Interest Expense -$ 137,113.00$ -$ 137,113.00$ (137,113.00)$ *

Land 3,000,000.00$ 2,656,812.47$ -$ 2,656,812.47$ 343,187.53$ *

71,045,912.97$ 68,406,411.14$ 1,481,028.37$ 69,887,439.51$ 1,158,473.46$

* Commission to confirm amounts *

meeting minutes may 21, 2019 - nrdrwwsc€¦ · tim timmons, manager of corporate services, lacombe...

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