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PNCWA LCS E-NEWSLETTER 3RD QUARTER 2013

On July 17th, Lynne Chicoine from CH2M-Hill and Tim Munro, senior operator at theCity of McMinnville Water Reclamation Facility (WRF), gave a presentation and tour ofthe McMinnville treatment plant.

While attendees en-joyed the pizza provid-

ed, Tim Munro first re-viewed the treatment

plants history. Built inthe 1950s, the original

treatment plant used atrickling filter for sec-ondary treatment. Alt-

hough it was upgradedin the 1970s with con-ventional aeration ba-sins, the City was found

to be the largest point source contributor of phosphorus to the South Yamhill River.With a total-phosphorus (T-P) limit of 0.07 mg/L and ammonia limit of 0.5 mg/L ,theWRF typically discharges effluent with less than 0.05 mg/L ammonia and 0.05 mg/L T-

P. This exceptional treatment protects the South Yamhill River during low summerflow.

Next, Lynne Chicoine discussed the planning process for the plant expansion sched-uled to start in 2014. A third train (Orbal oxidation ditch & secondary clarifier) was ini-tially planned, in order to meet expected increases in organic loading, provide redun-dancy and buffer the plant hydraulically during the winter months. New earthquakeprotection requirements however caused concern over the affordability of anotherOrbal due to its large footprint. Consequently several alternatives were consideredincluding a vertical loop reactor, conventionalaeration basin, a moving bed biofilm reactor andan external anaerobic zone for enhanced biologi-cal phosphorus removal. After evaluating all ofthese options, it turned out that another Orbal was

the most cost effective way to meet the futureneeds of this plant.

FACILITY TOUR: McMinnville WRF


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The plant tour featured both liquid and solids processes. Raw sewage is pumped 1.5miles through a force main up to the headworks second floor where it flows throughscreens, undergoes grit removal and moves on to the oxidation ditches (Orbals) wherenutrients are removed biologically by flowing through anaerobic, anoxic and aerobiczones. Flow continues to the secondary clarifier and then to tertiary clarifiers wherephosphorus and solids are removed chemically with a mixture of Alum, ACH and poly-mer. Tertiary effluent flows through sand filters where the last bit of solids is removedbefore UV disinfection and discharge at the outfall.

Solids processing consists of gravity belt thickening and ATADs (autothermal thermo-

philic aerobic digesters). With temperatures usually reaching well above

60 degrees C (140 F) these digesters use heat created by bacterial metabolism to kill

pathogenic bacteria. The Class A Biosolids is then used locally by farmers.

FACILITY TOUR: McMinnville WRF


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The WEF website is a great place to go for practice tests. Go to http://www.wef.org/SkillsBuilderand trytheir online tests. Here is a practice test with answers later in the newsletter.

1. As part of the national pretreatment program (40 CFR Part 403), plants with a design flow of more than____________ must develop an industrial waste pretreatment program.

a. 38 000 m3/d (10 mgd)b. 38 000 m3/d (10 mgd)c. 76 000 m3/d (20 mgd)d. 19 000 m3/d (5 mgd)

2. The desired solids loading rate for a 80-ft diameter clarifier is 40 lbs/day/ sq ft. If the flow to the clarifieris 6.5 MGD, what is the required MLSS concentration?

a. 4615 mg/L

b. 3707 mg/Lc. 3920 mg/Ld. 3517 mg/L

3. UEL and LEL are terms related to gases and vapors in wastewater treatment. What do these termstypically define?

a. the exposure limits of common gasesb. reactive limits of common gasesc. the explosive limits of common gasesd. entropy or dissolution limits of these gases

4. The term Doppler refers to a(n) _______________ meter.

a. ultrasonic flowb. magnetic flowc. pHd. temperature

5. A water-filled mechanical pump seal not only helps to prevent leaks, but also ___________.

a. keeps the pump primedb. acts as a reserve water supplyc. prevents pump shaft weard. cools the material being pumped

6. The primary compound formed when chlorine gas is introduced to water is ____________.

a. bromine chloride

b. sodium chloridec. Chloroformd. hypochlorous acid

WASTEWATER CERTIFICATION QUESTIONS:


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7. A limiting factor for digester loading is ___________.

a. pathogen contentb. sludge colorc. pathogen typed. hydraulic detention time

8. The presence of large amounts of filter flies could be caused by any of the following conditions except____________.

a. tall grass and weeds present around the trickling filterb. insufficient spray reaching the outside wall of the trickling filterc. excessive hydraulic loadingd. plugged spray orifices or nozzles

9. The primary method of nitrogen removal in constructed wetland treatment system is

______________________________.

a. plant or algal uptakeb. Volatilizationc. nitrification/denitrificationd. precipitation adsorption in soils

10. 1 cu ft/sec is equal to ________.

a. 500 gpmb. 0.72 mgdc. 0.65 mgdd. 30024 gph

11. The surface overflow rate for a settling tank is determined from the ___________.

a. volumetric flow divided by the tank volumeb. product of the volumetric flow and tank surface areac. sum of the volumetric flow and tank surface aread. volumetric flow divided by the tank surface area

12. The maximum weir loadings for secondary clarifiers range from _____________.

a. 80 120 m3/md (6400 9600 gpd/ft)b. 300 500 m3/md (24 000 40 000 gpd/ft)c. 50 75 m3/md (4000 6000 gpd/ft)d. 125 250 m3/md (10 000 20 000 gpd/ft)

Solutions on Pages 12-14

WASTEWATER CERTIFICATION QUESTIONS:


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On Wednesday, August 7thmembers of the LowerColumbia Section of the Pacific Northwest Clean Water

Association met at Portlands beautiful Laurelhurst Park forthe First Annual Summer Picnic. It was a warm, lovelysummer evening and Joel Borchers of Clean Water Servicesdonned an apron to barbeque, to perfection, burgers anddogs. The burgers were served with all the accoutrements

and traditional side dishes of cole slaw, baked beans andpotato salad were provided. The children enjoyed a walkaround the park and a chance to watch the ducks on thepond.

If you were unable to attend this year, do not fear. The plan

is to make the Summer Picnic an annual tradition. See you

next time!

2012 Award Winner Presentation

The City of Dundee receives theirplaque for winning the 2012 LCS

Project of the Year

Kevin Wegener was the2012 LCS

Operator of the Year

LCS Annual Summer Picnic


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The Oak Lodge Sanitary District completed its WaterReclamation Facility improvement project in October2012. The improvement project included a new

influent pump station (submersible pumps),

headworks (screens, compactor, Head Cell gritremoval), new biofilter, new aeration basins (high

speed turbo blowers, nitrification/denitrification),

new clarifiers, new UV disinfection system andaerobic digesters (jet mix system). The District also

integrated new SCADA (Wonderware), CMMS

(Lucity) and LIMS (Hach WIMS) systems into thecompleted project. The District retained its solids

processing systems which include gravity belt

thickening and belt filter press. Currently, the facilityis focused on the startup and performance testing of

the Cannibal system. We are also transitioning fromanaerobic digestion to aerobic digestion.

The Cannibal solids reduction system is unique to the Northwest and has been online since January 2013.Performance testing began in July 2013 with the system currently producing a biological yield of

0.35 lbs. WAS/lb of Inf. BOD. The Cannibal process replaced a 1960s vintage high rate activated sludge

process that produced as much as 1.2 lbs. WAS/lb of Inf. BOD.

The tour will encompass all process areas and include a presentation of data related to the Cannibalsystem. CEUs will be awarded.

Please join us on Wednesday September 25th, 11:30 am, at the Oak Lodge WRF,

13750 SE Renton Ave., Oak Grove, OR, 97222. Contact Dana with any questions -

[email protected]

Upcoming Tour: Oak Lodge Water

Reclamation Facility


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The Lower Columbia Section strives to provide educational opportunities for those in the

field of wastewater treatment. We work to do that by offering social events, scholarships,workshops and promoting plant tours around the area. None of this would be possible

without the generous support of our sponsors.

On behalf of the entire Lower Columbia Section of the Pacific Northwest Clean Water As-sociation, we would like to thank:

SUPPORTERS OF PNCWA-

LOWER COLUMBIA SECTION

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ADVERTISING OPPORTUNITIES ARE NOW AVAILABLE!Contact Joel Borchers at [email protected]

for information on sponsorship and advertising.

Thanks to these sponsors!Thanks to these sponsors!Thanks to these sponsors!Thanks to these sponsors!

Brown and Caldwell

Carollo Engineering

Clean Water Services

HDR

Murray Smith and Associates

and a special thank you toRichwine Environmental.


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PNCWA Lower Columbia Section CONTACTS

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Name

Officers

E-MAIL

Joel Borchers President [email protected]

Dana Devin-

Clarke

Vice President &Young ProfessionalsCommittee Co-Chair

[email protected]

Bhargavi

Maremanda Secretary-Treasurer [email protected]

Priya Dhanapal Section Director [email protected]

Tim Munro Scholarship Chair [email protected]

Jeff Hart Newsletter Chair [email protected]

Susan Gierga Section Director [email protected]

Mike Kebbe Section Director [email protected]


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WEF/PNCWA/LCS Mark your Calendars!

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Contact Jeff Hart at [email protected] advertise your event in our newsletter.

When Where What Affiliation Contact

Sep 25,2013

Oak Grove,OR

Oak LodgeWRF Tour

LCS Dana [email protected]

Sep 25-27,2013

Redmond, ORORWARN An-nual Confer-

enceORWARN Ross Turkus - [email protected]

Oct 5-9,2013

Chicago, IL WEFTEC WEF http://www.weftec.org/


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Were on the web! http://lowercolumbia.pncwa.org


1. Answer D: 19 000 m3/d (5 mgd)

The General Pretreatment Regulations of Existing and New Sources of Pollutionoutline the national pretreatment

program for the United States. The regulation requires any plant with a design flow over 19 000 m3/d (5 mgd)

to develop an industrial waste pretreatment program.

Reference: Water Environment Federation, Operation of Municipal Wastewater Treatment Plants, Fifth Ed.,

MOP 11, Vol. 1, pg. 56

2. Answer B: 3707 mg/L

3. Answer C: the explosive limits of common gases

UEL and LEL stand for the upper and lower explosive limits of a gas or vapor. These are the concentrations at

which there is a possibility of explosion from contact with heat or other chemicals.

Reference: Water Environment Federation, Safety and Health in Wastewater Systems, MOP SM-1, pg. 83

If you have an interesting project, a new process, or are just plainproud of your plant, let us know. We can organize a Plant Profilefor your facility. Contact Jeff Hart and let him know that you wantto show off! ([email protected])

Want to feature your plant in our newsletter?

SOLUTIONS TO WASTEWATERCERTIFICATION QUESTIONS:


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4. Answer A: ultrasonic flow

Doppler refers to a type of ultrasonic flow meter. The meter measures the frequency shift of ultrasonic wavestransmitted across a pipe. These shifts are then used to determine the flow rate.

Reference: Water Environment Federation, Operation of Municipal Wastewater Treatment Plants, Fifth Ed., MOP11, Vol. 1, pg. 154

5. Answer C: prevents pump shaft wear

Traditional mechanical pump seals with packing have begun to be replaced by fluid filled seals. While this notonly prevents leaks, this type of seal also minimizes any friction generated by the pump shaft


6. Answer D: hypochlorous acid

Chlorine dissolves quickly into water to form a mixture of hypochlorous and hydrochloric acids.


7. Answer D: hydraulic detention time

Two criteria may determine a digesters capacity Ethe hydraulic detention time and the volatile solids loadingrate of the incoming sludge. The detention time deals with the flow while the volatile concentration deals with howmuch treatment time will be required for that particular sludge.


8. Answer C: excessive hydraulic loading

Filter flies thrive in environments that get periodic light sprays of wastewater. High hydraulic loading to atrickling filter will keep media continually wet which is not conducive to filter fly breeding. Filter flies can alsobreed in grass and weeds around a trickling filter that receive occasional sprays of wastewater such as thatcarried by wind blowing across the trickling filter.

Reference: Water Environment Federation,Operation of Municipal Wastewater Treatment Plants, Fifth Ed.,MOP 11,Vol. 2, pg. 713-714

WASTEWATER CERTIFICATION ANSWERS:


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9. Answer C: nitrification/denitrification

In a constructed wetland system, microbes transform ammonia to nitrate through nitrification and other microbesconvert nitrate to nitrogen gas through denitrification.

Reference: Water Environment Federation, Wastewater Disinfection,MOP FD-16, pg. 233

10. Answer C: 0.65 mgd

11. Answer D: volumetric flow divided by tank surface area

The surface overflow rate for any settling tank is simply the volumetric flow rate divided by the tanks surfacearea. This will give the rate in terms of distance per unit time.


12. Answer D: 125-250 m3/m*d (10 000-20 000 gpd/ft)

For the secondary clarifiers of most facilities, benchmarks of clarifier operation include maximum weir loadingsof 125 250 m3/md (10 000 20 000 gpd/ft) and overflow rates ranging from 24 33 m3/m2d (600 800 gpd/ft2).

Reference: Water Environment Federation, Operations Training/Activated Sludge Process Control Training Manual,pgs. 2-12

WASTEWATER CERTIFICATION ANSWERS:

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