teex water educator 2-10

8/9/2019 TEEX Water Educator 2-10

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J ar Test ingby Jack SwansonJar testing is a pilot scale testthat is used by water treatmentoperators to simulate a full scalewater treatment process. Operatorsuse various types of treatmentchemicals that mimic coagulationand flocculation processes thatremove organic and inorganicmatter, colloidal particles of

turbidity, and microorganisms foundin raw water. System operators use1000 milliliter jars to determinewhich chemical works best withtheir systems raw water. Jartesting requires careful attention todetail. It also requires knowledgeof the systems actual mixingand stirring processes and howto mimic this using a jar testingmachine.

There is no set requirement onhow many jar tests should beconducted, but the more testsconducted the better the plantwill perform. Jar testing should done as seasons change, weathchanges, raw water charteristicchange, and whenever the systeis shut down or when part of thsystem is taken out of service fmaintenance. It should be every

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2010 - Issue

Water & Wastewater Training Program s Infrastructure Training & Safety Institute s Texas Engineering Extension Service s The Texas A&M University System s www.teex.org/www s 800-723-38


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The Water Educator newsletter is a Texas-based initiative sponsored by the Water & Environmental Training Program of the Texas EngineeringExtension Service (TEEX), a Member of The Texas A&M University System.

This newsletters purpose is to bring information to water and wastewater operators and their supervisors on items of technical and professiona

interest. The mission of the Water & Environmental Training Program is to serve Texans by improving health and safety. We do this by providinwater and wastewater operators with professional training and by making technical information available to improve operations.

The Water & Environmental Training Programs training and technical assistance outreach staff are located throughout Texas, with customeservice ofces located in College Station. We conduct training in water, wastewater, on-site sewage facility, backow prevention, and related topareas. Our environmental training specialists instruct environmental health and safety professionals nationwide. The Frank M. Tejeda Centefor Excellence in Environmental Operations has staff located along the Texas Rio Grande border with the mission to provide assistance to watesystems along the border and rural areas.

For more information: Phone:800-SAFE-811 (800-723-3811) Fax: 979-458-1426 Website:www.teex.org/www E-mail: [email protected]

It is the policy of the Texas Engineering Extension Service that all federal statutes will be followed pertaining to employment and

recruitment of students without regard to race, sex, color, religion, national origin, age or disability.

2 Water Educ

EEX now offers the Onlineazardous Materials Awarenessurse (WWW351).

is $25 course is designed forater, wastewater, and otherblic works and infrastructure

aff who need an introduction tozardous materials training but

ay not have the opportunity to

ke a more in-depth course.

nce you complete this onlineurse, you will have a betterderstanding of the dangersesented by hazardous materialsthe work place, and how tost protect yourself, others, ande environment.

ourse Topics

Hazardous materialoverview

Dangers

Recognition Protection Disposal Unintentional release

In order to take this onlinecourse, you MUST have:

Minimum of a 56Kmodem Internet

connection (however, abroadband connection isrecommended).

Current browser(i.e., InternetExplorer 6 orhigher, Firefox2.0 or higher,or Safari 2 orhigher).

Adobe Acrobat

Reader 7 orhigher. Adobe Flash 10.0

or higher.

To register for this course, gohttp://www.teex.org and searcfor WWW351.

After registering, you will recean e-mail with instructions forgetting started. If you do notreceive a confirmation withinone hour, please contact TEEInfrastructure Training & Safe

Institute at 800-SAFE-811 (80723-3811). Ask for the PublicWorks Training Director.

New Online Course


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Texas Engineering Extension Service

operators goal to optimize theplants performance and improvethe plants efficiency.

Finally, a jar test should berun to save money. Chemicalsare expensive. By optimizingcoagulation and flocculation,hundreds of dollars can be saved.A common problem of watertreatment is overdosing, that canhurt the quality of water while

costing more than when proper jartesting technique is followed.

Jar Testing P rocedure

The following is an example of howto perform a jar test. The chemicalused is alum (aluminum sulfate)commonly used in coagulation andflocculation, and a six-gang jartester with variable speed mixer.

First: Prepare a standard

solution of alum using a stocksolution containing 50% alumhaving a specific gravity of 1.2.

* 1.2 specific gravity 0.50 =0.6 gram equivalent weightof alum.

* 1 gram 0.6 gramequivalent weight = 1.67

mils equal one gram alum.

* 1.67 mils 10 = 16.7 milsequal 10 grams alum.

* Add 16.7 mils to 1000milliliter graduated cylinderholding some distilledwater and bring up to the1000 milliliter mark, mixthoroughly.

* This will provide an increasein dosage of 10 mg/L

when adding 1 ml in 1 mlincrements.

* Run as many jar tests asnecessary to determine theoptimized dosage.

(Note: Always use actualtreatment chemicals used inthe treat ment proces s.)

Second: Add 1,000 millilitersof raw water to each of thejars. Record temperature, pH,turbidity, alkalinity and TOC ofthe raw water (See Table 1).

After dosing each jar, turnon stirrers. This part of theprocedure should mimicthe actual conditions of theplant. After coagulation and

flocculation are completedturn off the stirrers and allfloc to settle. Underfeedingcoagulant will cause a clouappearance with little or nfloc formation. Overfeedingcause a dense fluffy floc toform and will settle very slThe best way to determineproper dosing is to run aturbidity test on each samThe Texas Commission on

Environmental Quality (TCrecommends turbidity of 2or less as being optimized

Proper jar testing will providelonger filter runs, and a greatereduction of microorganisms aorganic matter while using lesfilter water to backwash and cthe filter. It also provides for buse of coagulant chemicals. Msure you are properly performa jar test so that you are prov

the best product available to ycustomers.

Note: Jack Swanson is anassociate training specialist inthe TEEX Public Works TrainiProgram.

Water Educator

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Mark E. Goad

e TCEQ has formally adopted theound Water Rule. The new ruleplies to all public water systemsat provide ground water. It alsoplies to systems that mix surfaced ground water if the ground wateradded directly to the distributionstem and provided to the customerhout treatment. The intent of thee is to provide additional protec-n of ground water sources against

sease-causing organisms. Compli-ce requirements in the rule began

ecember 1, 2009.

e rule has four major sections:

Periodic sanitary surveys con-ducted by TCEQ Regional Officepersonnel to identify significantdeficiencies. The survey willevaluate eight elements of a publicwater system.

Source water

Treatment

Distribution system Finished water storage

Pumps and controls

Monitoring, reporting and dataverification

System operation and management

Operator compliance with staterequirements

TCEQ will require corrective actionfor any system with significant

deficiencies or one which has asource water fecal positivesample. Corrective action willrequire one or more of the follow-ing options:

Correct all significant deficien-cies.

Provide an alternate source ofwater

Eliminate the source of con-tamination.

Provide treatment that reliablyachieves a 4-log (99.99) treat-ment of viruses using inactiva-tion or removal or a TCEQapproved combination.

Well disinfection in accordancewith AWWA procedure C654-03.

A TCEQ specified period ofsource water monitoring.

3. If treatment

technology hasbeen installedto comply withthe rule, compli-ance monitoringwill be requiredby TCEQ toinsure a 4-log(99.99) treat-ment of virusesis achieved andmaintained.

4. Triggered source

water monitoringfor any systemnot treating fora 4-log inactiva-tion of virusesif the systemreceives apositive sampleduring routinemonthly bacte-riological testing.

If a public groundwater system

receives a coliformpositive sampleduring routinemonthly bacterio-logical testing, thesystem must takea source watersample within 24hours. TCEQ canwaive this require-ment if it can bedetermined that

the positive sample was a resultdistribution problem and not a sowater problem. In either case, Tmay require immediate correctivaction to address the source of tcontamination.

There are three monitoring optiofor systems to use under the GroWater Rule:

1. Systems can conduct a CT s

4 Water Educ

The Texas Gro


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and submit the results to TCEQ for approval toindicate the system is achieving 4-log treatmentof viruses, and then conduct daily or continuousdisinfectant residual monitoring to document the4-log treatment is maintained.

Systems can opt to perform triggered source watermonitoring as outlined in a source monitoring planthat must be approved by TCEQ. All ground watersystems are subject to some type of triggeredsource water monitoring if the system does notreliably achieve a 4-log treatment of viruses by

removal, inactivation, or a combination of both.

3. A system can do nothing until they have a positivecoliform sample during routine monthly bacteriological testing, and then pull a source water samplewithin 24 hours from each active well.

Options 1 and 2 require prior TCEQ approval. Option3 requires no action at all until the system receives apositive coliform sample during routine monthly testing

The rule does allow TCEQ to require source watermonitoring for assessment if a well is at risk of con-tamination based on the following parameters:

Wells in sensitive aquifers such as karst, fracturedbedrock, and gravel.

Wells in shallow, unconfined formations.

Wells in aquifers with little soil cover.

Presence of potential sources of contamination.

Location and depth of the well.

Wells that have previously been identified as beingfecally contaminated.

Option 3 is probably the best option for most systemsthat do not have a large number of wells and have a

history of very few positive samples during routinemonthly bacteriological testing. In conversations withgroundwater system operators in East and SoutheastTexas, Option 3 is apparently the universal choice.

Further information can be obtained from the TCEQWebsites Ground Water Rule Main Page. The websitaddress is: http://www.tceq.state.tx.us/permitting/water_supply/pdw/microbial/gwr_main.html .

It also links to several other sources of informationregarding the rule.

Make sure your system is in compliance with the new

rule.

References: TCEQ Ground Water Rule Main Page,and Ground Water Rule Teleconference Notes, July17, 2009

Note: Mark E. Goad is an associate training specialisin the TEEX Public Works Training Program.

Water Educator 5

ndwater Rule


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Compliance Corner

Chlorine Meter Calibrations - Operator Basicby Keith McLeroy

Are you in calibration compliancewith your chlorine analyzer? Whenwas the last time you analyzed liquidprimary chlorine standards of knownconcentrations? Monitoring of eitherfree or total chlorine in drinking watersand wastewater effluents has specificcalibration and quality assuranceregulatory language. The regulationsare found in 30 TAC 290 for drinkingwater and 30 TAC 319 for wastewater

effluent.The exact language for 290.46. is:

(2) Laboratory equipment used forcompliance testing shall be properlycalibrated. (C) Disinfectant residualanalyzers shall be properly calibrated.(i) The accuracy of manual disinfectantresidual analyzers shall be verified atleast once every 30 days using chlorinesolutions of known concentrations.

The exact language for 319.6. is:

The permittee shall assure the quality of allmeasurements through the use of blanks, standards,duplicate analyses, and spikes. At a minimum, thequality assurance requirements specified in Table 3in 319.9 of this title (relating to Self-Monitoring andQuality Assurance Schedules) shall be utilized.

Table 3 reads: For the oil and grease analysis andchlorine-total or free analysis, standards shall beanalyzed on a 10% basis. If one to 10 samples areanalyzed on a particular day, then one standard shallbe analyzed. Duplicates may be analyzed in lieu ofstandards for the oil and grease analysis and chlorine-total or free analysis.

Lets review this in a simplified manner. For 290, itsays chlorine solutions of known concentrations.This means that those standards must be a liquid typesolution, know as a primary standard. For example youcan make a liquid chlorine standard of 1.00 mg/L. or anyother concentration as needed. This type of standardis not the gel color standards (known as secondarystandards) that are commonly used in many types ofhand-held or bench-top chlorine meters. Secondarystandards are to be utilized to verify the metercalibration, not for the accuracy requirements, nor to

calibrate the meter. Thus, you need liquid standardsa known chlorine concentration amounts to comply w

the drinking water regulations.

For the 319 regulations there is the option of analyziduplicate samples of the effluent instead of testingliquid primary standards. Keep in mind, though, thatyou still need to check the meters calibration using tsecondary color standards.

In addition, if your laboratory or utility uses the samechlorine analyzer for both your effluent and drinkingwater testing, then you must comply with the 30 TAC290 requirements. The drinking water regulationchlorine monitoring quality assurance supersedes th30 TAC 319.

Primary chlorine standards are available from mostlaboratory supply vendors, and instructions for makinthe specified levels needed and how to calibrate youmeter will be found in the instruction manual of themeter. Do not forget to document all calibration andverification data in you laboratory meter log book asthose are also requirements in both 290 and 319.

NOTE: Keith McLeroy is an associate training speciin the TEEX Public Works Training Program.

6 Water Educator


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Water Educator 7

y Mark E. Goad

the previous issue, we discussed the fact that the phraseactivated sludge referred to a general treatment processnd was not a detailed description. To properly operater troubleshoot a specific activated sludge plant, you mustnow what modification of activated sludge is being used. Inis article we will look at the extended air modification. Also

nown as racetracks and orbitals, it is probably the most-ten utilized process in Texas.

eration basin detention time separates extended airom the other modifications. The other activated sludgeodifications have detention times ranging from four toght hours. Extended air ranges from 18 to 36 hours ofetention time. This particular modification holds the waste-ater in contact with the bugs and air a lot longer. In thisodification the microorganism population is kept high in

elationship to the food supply (low F/M ratio), and the age ofe organisms is kept high (MCRT). This process operateswhat is described as the endogenous growth phase ofe bacteria. This modification keeps the bugs starving and

annibalistic. In return, they reduce the solids to the lowestossible levels. The extended air plant is both an activatedudge and an aerobic digester in one. That is why manyxtended air plants do not need a separate digester. Whenou remove the solids from the aeration basin, the solids areeady for dewatering and disposal.

he chart below lists the typical operating parameters ofxtended air.

his modification is operated at very low F/M ratio andhigh sludge age (MCRT). The air minimum is 1 mg/Lstead of 2 mg/L for the other processes. These operatingarameters keep the bugs starving. This is why a primaryarifier should never be added to an extended air process

ant. The primary clarifier would remove 35% of the

influent BOD (food supply) from bugs that are already starv-ing. This process modification is efficient achieving 95%to 96% BOD removal and does an excellent job convertingammonia.

A variant of the extended air process is the racetrack, alsoknown as the oxidation ditch. Usually an oval shaped trackwith a set of rotors or brushes on each side that propels thewastewater around the track, this type of plant is a favorite inthe rural areas of Texas.

Another variant is the orbital which uses three or fourdifferent tracks instead of one. The orbital tends to be amore efficient use of space than a race track. In either caseif aeration detention time is 24 hour plus, these variantsoperate and achieve the same results as an extended airplant. If aeration basin detention times are designed around18 to 20 hours, then a separate digester may be needed.

Just remember, no matter what activated sludge processyou operate, you need to know the specific modification andyou need to know the operating parameters. Make sure thayou operate your facility within those parameters to ensurethe best possible effluent is being discharged back into theenvironment.

Note: Mark E. Goad is an associate training specialist in theTEEX Public Works Training Program.

xtended Air Process:

Activated Sludge


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A Member of The Texas A&M University System

Non-ProfitU.S. Postage

PaidCollege Station

Texas 77840Permit No. 21

Water & Wastewater Training ProgramInfrastructure Training & Safety InstituteTexas Engineering Extension ServiceThe Texas A&M University System301 Tarrow, TEEXCollege Station, Texas 77840-7896

www.teex.org/www800-SAFE-811 (800-723-3811)

Ad Code: W10NB1

What are

he operat or

basics for

chlor ine met er

cal ibrat ions?

Learn more about training and

technical assistance available to

Texas water operators

at www.teex.org/www.

C10.4159.04

See

Complianc e Corner

on page 6.

teex water educator 2-10

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