january 2013

wsomag.com January 2013 7

In many endeavors, frequency matters. In advertising a product, it takes several exposures to bring a prospect to the point of buying. In fishing, you have to keep casting. To grow a lawn, you have to keep watering — or those green sprouts turn brown.

In publishing, if you want a magazine to make an impression on read-ers, it needs to be there frequently. So, WSO is going monthly, as of this issue. Last year we dipped a toe in the water with every-other-month issues. Readers’ reactions tell us the water is fine. So we’re plunging in.

And, in keeping with the Internet age, we now offer online-only arti-cles. Actually, we’ve been doing that for a few months. The online side helps us bring you articles of timely interest — something a monthly

magazine just can’t do. Colleague Briana Jones heads up that area.

Look to the print magazine articles on technical topics, sus-tainability initiatives, and appli-cations of new equipment and technology, and for profiles of excellent operators, water plants and water systems.

Remember, this magazine is yours, and so is the online content. Tell us about the great things you and your team members are doing, and we’ll consider sharing them

with our readership of more than 30,000 water operators, superintendents and managers. Our aim is to help you share best practices, celebrate achievements, recognize and promote excellence and, above all, deliver the highest-quality water to customers.

Drop me a note to [email protected] and I promise to respond.

• • • • •This issue’s articles on Bellingham, Wash., and Syracuse, N.Y., are

noteworthy for the approach these water systems are taking to ensure supply and quality. Instead of focusing solely on water plant operations, the teams look upstream at how to protect their source waters.

Higher Frequency — and a New ChannelResponding to readers’ warm welcome, WSO upgrades to a monthly publication. We’re also offering exclusive online articles with information to help you excel.

ONTAP

BY TED J. RULSEH, EDITOR

Remember, this magazine is yours ...

Our aim is to help you share best practices, celebrate achievements, recognize and promote excellence and, above all, deliver the highest-quality water to customers.

Watershed approaches to water quality are not new, and in fact are gaining favor, but we tend to see more attention to that area on the wastewater side. Nutrient reduction is a huge issue for wastewater treat-ment plants, and one alternative to costly plant upgrades is to remove those nutrients (mainly nitrogen and phosphorus) from the lakes and streams by other means, such as progressive farming practices and ero-sion control.

Now it appears the drinking water side is turning in a similar direc-tion. That can only be a good thing. After all, water doesn’t obey political boundaries like city limits and county lines. It obeys gravity; that’s how we get watersheds. Learning to approach water quality on a watershed basis requires new ways of thinking.

• • • • • And on the subject of thinking, the Brazos River Authority in Texas

has new thoughts on how to educate citizens about the importance of water quality and conservation (see “Winning Them Over” in this issue).

We see lots of water agencies sponsoring education programs for chil-dren, and of course they’re great. The Brazos authority’s online Water School caters to adults. This turns on its head the conventional idea (a sound one, by the way) that habits form early and we need to teach good behaviors to members of the next generation — who may then influence their parents.

An adult-oriented approach reaches the people who make the water usage and water infrastructure spending decisions today — and in the bargain are in a pretty good place from which to influence kids.

If we’re going to fight that battle of public education, it makes sense to fight it on both these fronts. So here’s a hat tip to the Brazos River Authority.

We hope you enjoy this and future monthly issues of WSO. wso


return to natural conditions to reduce phosphorous to an acceptable 2,400 pounds per year.

In 2013, the DOE plans to include TMDL compliance as part of new NPDES stormwater requirements. Lake stakeholders know that meeting the TMDLs for phosphorus and dissolved oxygen will take many years.

Improving the watershed

Meanwhile, the Lake Whatcom Management Program continues to monitor lake water quality and take steps to reduce phosphorus levels. Nine tributaries to the lake are routinely monitored, as is the lake itself in the deepest part of each of the three basins. Monitoring is also conducted at the city intake and at an additional point in Basin 3 (the largest).

Raw water samples are collected at the city screen house and at vari-ous points in the water plant.

The Lake Whatcom Management Program’s 2011 Annual Progress Report, prepared by the ICT in March 2012, highlights accomplishments and provides recommendations for 2012. Accomplishments for 2011 include a cost benefit study by CH2M HILL of activities that can prevent or reduce phosphorus loadings.

Other highlights are stormwater capital improvement projects in the watershed and community education efforts that include a bimonthly e-newsletter and a new Lake Whatcom Management Program website.

“The city, county and Lake Whatcom Water and Sewer District coop-erate to implement annual work plans to improve and protect lake water quality,” says Clare Fogelsong, environmental resources manager for the city Public Works Department. “The annual plans are comprehensive and include a wide range of actions that address several threats to the

lake. The recent focus has been to reduce nutrient loading into the lake.”A five-year work plan describes a number of tasks to be pursued, deal-

ing with program areas that include watershed ownership, land develop-ment, stormwater management, data and information management, utilities and waste management, spill response, transportation, recre-ation, and community outreach.

Clogged filters

Today, the water treatment plant team deals regularly with the conse-quences of phosphorus. Algae in Lake Whatcom has been steadily increasing for the past decade, and it peaked in the summer of 2009, when a slime produced by the blue-green algae clogged the water plant’s filters.

Contributing factors included a heavy January rainstorm that deliv-ered a huge load of phosphorus-laden sediment, and a wet spring that washed more sediment and nutrients than usual into the lake — just in time for record-setting hot summer weather.

Treatment plant operators saw decreases in the Unit Filter Run Vol-umes (UFRVs) — a measure of how much water passes through each square foot of filter media before it clogs and needs backwashing. “The UFRVs are typically 6,000 gallons per square foot during winter and 3,000 during summer,” says Bill Evans, chief plant operator. “In the sum-mer of 2009, the UFRVs decreased to 900 gallons per square foot for sev-eral days.”

Filter run times decreased from 12 hours to 3 1/2 hours, and clean fil-ters were placed online every 30 minutes to replace the ones being back-washed. “It became difficult for the operators to keep up,” says Evans. “As soon as we backwashed a filter, the next one would come due.”

All this cut plant capacity to below customer demand and below the volume required to maintain fire flows. When voluntary water conserva-tion measures proved inadequate, the city enacted mandatory watering restrictions, reducing demand sufficiently in just two days. “Fortunately, the algae did not cause any taste and odor issues with the city’s drinking water,” says Evans.

Operational headachesWhile frequent backwashing was taxing, a power failure on July 29,

2009, during the hottest day on record, made things even worse. “We called the power company to report the outage,” recalls Evans. “Our gen-erator ran for about 20 minutes before it overheated and shut down, which was the operators’ worst nightmare. When power company staff finally showed up at the plant, they said there was nothing they could do because we owned the service equipment into the plant.”

The Bellingham Water Treatment Plant uses

an inline filtration process in which a floccula-

tion-enhancing chemical is added just before

filtration. Source water is Lake Whatcom, and the

city has additional water rights from the middle

fork of the Nooksack River.

Lake water enters a submerged intake that

was constructed in the 1940s, then travels by

gravity into a gate house and a tunnel to the

screen house, which removes fish and debris.

After chlorination, a pipeline conveys the water to

the treatment plant.

At the plant, the 66-inch-diameter pipeline

divides into two 24-inch-diameter pipelines that

lead to two rapid mixing basins. From those

basins, the water flows into a common water

channel, and then to six granular-media filters

using AWI underdrains. After the filters, the water

flows into a 1-million-gallon clearwell and then is

delivered to a 16-million-gallon reservoir for

disinfection and distribution.

Capital Controls and Severn Trent supplied

equipment for chlorine addition at the plant

and screen house. At the treatment plant, the

alum system was supplied by UGSI ChemFeed

Inc. (Encore 700 pump) and General Chemical.

Soda ash addition (MERRICK Industries feeders

and Brenntag Pacific) raises the pH of the

treated water.

TREATING THE WATER

Anthony Lorenz checks raw water entering the plant (Hach sc100 controller and 1720E turbidimeter; Chemtrac PC 2400 particle counter).

When Evans asked the power company to check to see if power was even coming into the plant, power plant staff found and repaired a loose wire that had caused the outage. “The power was out for an hour, causing us to lose an estimated 2.3 million gallons of water in our gravity reser-voir,” says Evans.

During the height of the algae problem, filter backwashing used about two million gallons of water per day. Operators optimized the amount of treated water used to clean the filters, and adjusted raw water screen wash times to reduce raw water turbidity, which was above 1.0 NTU, rather than the usual 0.45 NTU. The operators also increased chemical coagula-tion doses to maintain treated water quality.

Even with the water use restrictions, operators had to backwash more often than normal. “The frequent backwash issue lasted from July through

October, and returned to normal levels when the cooler fall weather reduced algae growth,” Evans recalls. Since then, the plant has gone through sev-eral upgrades to help the situation:

• New 75 hp vertical pump motors (U.S. Motors/Nidec Motor Corpo-ration) for redundancy, and new electrical service equipment, including an automatic transfer switch to reduce outage risks.

• Air scour system (HSI blower and AWI underdrains) to reduce backwash water use.

• New motor control cabinet (Allen-Bradley/Rockwell Automation) and plant main switchgear (Schneider Electric) to update the elec-trical system and reduce failure risk.

• New 1,000 kW emergency generator (Baldor).

Many tasks The Bellingham plant’s seven operators are responsible for water and

wastewater operations, including monitoring and operation of 14 storage reservoirs (29 million gallons of storage) and 14 pump stations. Two oper-

ators run the water plant and two run the wastewater plant during normal business hours. After hours, one operator monitors both treatment plants with the SCADA system.

Water plant operators report to Evans, who sets performance goals. They make production-change, filter-backwashing and disinfection-dose-rate decisions, make all process control adjustments and checks, and han-dle customer service calls after hours.

Evans, who reports to superinten-dent of operations Bob Bandarra, holds Class 4 water treatment plant and water distribution licenses and has been with the city for 33 years. His team includes lead operator Karl Lowry (Class 3, 19 years) and operators Gary Hess (Class

3, 41 years), Randy Osborn (Class 3, 38 years), Gary Gilfilen (Class 4, 33 years), Sally Pytel (Class 3, 12 years), Keith Fredrickson (Class 3, 9 years), and Shayla Frances (Class 3, 7 years).

Well-trained

“Training the operators on both the water and wastewater facilities gives them a broad background,” says Evans. “They know both systems well, and even though it takes longer to train them, it makes them much more knowledgeable.” The operators appreciate the variety of work at the two plants, and cross-training allows more flexibility when operators take vacation.

The plant team conducts annual tours for groups, including Western Washington University water-quality classes and Bellingham elementary school students. “It used to be part of the fifth grade curriculum,” says Peg Wendling, laboratory supervisor for the Bellingham plants. “They still use a video series on water resources and treatment that the city developed 10 years ago. Bill Evans is featured prominently in that series as Bill Y the Water Guy.”

“The UFRVs are typically 6,000 gallons per square foot during winter and 3,000 during summer. In the summer of 2009, the UFRVs decreased

to 900 gallons per square foot for several days.”BILL EVANS

Jim Walton attends to routine maintenance.

Chief plant operator Bill Evans.

16 WATER SYSTEM OPERATOR

Woodard & Curran colleague Paul Roux has known Geary for more than 10 years, and says he can balance “a hundred things at once. He’s very cool under pressure.”

In turn, while Geary believes the water management field offers both job satisfaction and security, he has no misconceptions about the chal-lenges. “It can be demanding,” he says. “You give up a portion of your life being on call on weekends and in the middle of the night. Ours is a 24/7 commitment.

“But I find it interesting. The technology is always changing, you’re always learning about new things. Problem solving can be a lot of fun.”

He says a key to success, at Lawrence or anywhere, is to get people well trained in all areas of the plant and its operations. “We like to cross-train our people, so they can do a little bit of everything – laboratory work, operations, maintenance, sampling,” he says. “If you do that, you’ll have a much more well-rounded staff. It’s better than having just one per-son who knows everything.”

Confidence building

The cross-training and the confidence Geary instills in his staff pay off time and again. “Just this afternoon, we were looking at a trihalometh-ane issue we sometimes have in the far reaches of our distribution sys-tem.” Geary reflects. “We wondered if it might be because of carbon in

the bottom of the clearwell affect-ing the THM level.

“We sent a Sentry robot down to take a picture of the bottom, but we couldn’t tell if the black stuff down there was carbon or just some staining. Then one of our opera-tors suggested that we send our Sludge Judge (Nasco) down there to take a sample. It turned out it wasn’t carbon, but it was a simple idea for sampling that nobody had thought of before, and it worked.”

One of Geary’s long-term goals is to get more young people inter-ested in the field. “This is a very stable career choice,” he says. “Good operations people are always in demand. You rarely have to worry about finding a job.”

Roux observes that Geary is “exceptional with the staff reporting to him. He’s very fair, and aware of everything his people face. He stresses career development and works hard to take people under his wing and train them so they can pass the exams and get a job at a water facility. He’s done that with at least 10 people I know of. He wants them to stay in the industry.”

Geary summarizes his profession: “I always tell people that the good part of this job is people always need water. The bad part of this job is people always need water.” He could say the same about his banjo-play-ing: “The good news is people like to hear good music. The bad news is people like to hear good music.” wso

In addition to managing water treatment plants, playing in a

band, and being a husband and father of two, Joe Geary is a standup

comic. “When we have meetings with all our people from around the

country, we’ll rent a comedy hall and have Joe do his comedy

routine,” says Paul Roux, Geary’s manager at Woodard & Curran.

And what does a mild-mannered, understated water plant

manager do to make people laugh? “He’s great at roasts, and telling

jokes,” says Roux. “His stories and the twists he puts on family experi-

ences and events are especially funny.”

Geary says he started doing standup comedy about five years

ago, appearing before a variety of audiences, including the

company crowd. “My humor is mainly dead-pan delivery and

self-deprecating,” he says. “I get my stories from life experience, funny

events which I have a knack for remembering, like the time I acciden-

tally took my dog’s heartworm pill.”

A characteristic Joe Geary line? “I wouldn’t be so paranoid if

everyone wasn’t out to get me.”

A STANDUP GUY

MORE INFO:

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Nasco800/558-9595www.whirl-pak.com

Rockwell Automation414/382-2000www.rockwellautomation.com/industries/water

Woodard & Curran800/426-4262www.woodardcurran.com

Successful careerWoodard & Curran began working with the city

as the new plant was being phased in. The old plant across the street, built in the 1930s, continued to oper-ate until the changeover was complete in 2007. Geary was assigned to operate the old plant, while the oper-ators were trained on the new facility. The new plant represented a big step forward in technology for the city, and ultimately the city hired Woodard & Curran to operate it. Geary became the lead operator.

It’s the latest job in a 23-year career that Geary calls both secure and satisfying.

“I started out pursuing a degree in business administration,” he says. “But my sister was working in a water treatment laboratory, and she got me inter-ested in water and wastewater.” He took courses at University of Massachusetts Lowell, passed the state licensing exams, and got a job at the Lynn Water Treatment Plant (in his hometown), working for a contract operator.

Excelling in his role, Geary was assigned to man-age the startup of a treatment plant in North Adams, Mass., and later be the manager of utilities at Salem, N.H., before joining Woodard & Curran 11 years ago. He holds both Class 4T (treatment) and Class 3D (dis-tribution) certifi cations for Massachusetts and New Hampshire.

“I’ve learned a lot through experience and through studying on my own,” he says. “Over the last couple of years, I’ve been trying to learn more about SCADA controls and electronics. I have people who know it like the back of their hands, but you really need to under-stand more about it when you’re working with them.”

The Lawrence assignment has put his qualifi cations, and those of his six staff members, to the test. “We have a lot of new bells and whistles here,” he says. Plus, the state regulatory authorities handed down a list of some 170 consent order items that the new plant had to address when Woodard & Curran took over.

It’s about the team

Geary’s team has worked through the list and had satisfi ed all but two of the items by last summer. That kind of performance doesn’t surprise Sam Torissi, water and sewer supervisor for the city. “He’s the most even-keeled and knowledgeable person I’ve dealt with in the water busi-ness,” he says.

“We had numerous issues with the new plant, and he has corrected each and every one of them. But it’s more than that. There were a lot of lit-tle things in the new plant that didn’t work. The air conditioning wasn’t heat-sensitive in one of the rooms, a polymer pump was in the wrong place, a valve was rusting. He went through the entire plant and fi xed countless little things.”

Geary will tell you his team is responsible for the success. Teamwork is on his mind continuously: “When I drive to work in the morning, I’m

thinking about who’s on duty and what their strengths are. If it’s the guy who’s the computer whiz, then I’ll have him look at computer stuff while

he’s there. Another person is good mechanically, so we’ll get at those things.”

He tries to be pragmatic, but admits it’s not easy and takes discipline. “I delegate a lot, and I’m not going to nit-pick,” he says. “If you know the best way to get something done, then do it. If you have the right people working for you, it’s not a problem. I see my

job as big picture. Sometimes you have to be detailed, but if you dwell on the small things too much, you’ll go crazy.”

Peer review

Torissi says Geary’s style is widely admired among his peers: “When we go to consortium meetings with other cities in the Merrimack Valley, it’s amazing. He knows everybody, and he’s respected, gets high praise. He’s meticulous. When his company has a problem, they send Joe.”

“ I’ve learned a heck of a lot from the people I work with. We keep an open attitude so people feel free to contribute.

We’re all part of a team.”JOE GEARY

Joe Geary, shown monitoring rise heights in a clarifi er (Infi lco Degremont), leads his team with an inclusive style that encourages new ideas and approaches.


In a state that appears to be emerging from one of its worst droughts on record, keeping Texans up to date about water levels and sharing water conservation tips have been top priorities for the public information office at the Brazos River Authority.

But public education is another key responsibility, and public infor-mation officer Judi Pierce says it is a subject under constant review. In 2009, authority officials were discussing plans to update the education program when Pierce pointed out something she and her assistants had noticed: They get a lot of questions from adults.

The questions covered everything from “Why are you releasing water from the dam?” to “Can I dump my grass clippings in the lake?” As they discussed the questions, Pierce says, “One of our conclusions was that adult education is just as important as youth education.”

So, operating on a shoestring budget, Pierce and her assistants started a six-month process of developing the authority’s Water School, a blog-based online site that tackles a wide array of topics from water quality

and water supplies to recreational opportunities and future plans. The program was launched in April 2010.

Compiling questions

The Brazos River Authority has a mission almost as broad as the swath its borders cut across Texas. Headquartered in Waco, the state-chartered agency serves a 42,000-square-mile territory that includes all or part of 70 counties from the Texas-New Mexico border to the Gulf of Mexico. It owns three reservoirs — Possum Kingdom, Granbury and Limestone — and has contracts with the U.S. Army Corps of Engineers for water stor-age space at eight federal reservoirs in the basin.

The authority owns and operates water treatment systems at Lake Granbury (supplying wholesale customers in Hood and Johnson Coun-ties), the City of Taylor, and the City of Dime Box. It also partners with the Lower Colorado River Authority in a water treatment plant in Lean-der. The authority also owns and operates wastewater systems for two regional groups and several cities in its service area.

The first step in developing the adult education initiative was to com-pile an extensive list of topics based on the staff’s records and memories of public inquiries, a process that blended the concepts of “frequently asked questions” and “everything you wanted to know, but didn’t think to ask.” In other words, Pierce and her staff tried to anticipate questions they thought people could (or should) ask about their water sources.

WINNINGTHEM OVER

Just For Grown-UpsAn online Water School helps the Brazos River Authority educate adults about the importance of water quality and conservation

BY PETE LITTERSKI

“We used our in-house information technology resources to help us develop the site. And we

used freeware we found to develop the actual pages.”JUDI PIERCE

Possum Kingdom Lake Dam, the oldest of the three dams that the Brazos River Authority operates to supply a wide swath of Texas with water.

Public information officer Judi Pierce.

The Brazos River Authority’s online Water School.

Lots of interaction “People often don’t think about where their water comes from or how

it gets there until they have a problem,” says Pierce. The Water School is built on a framework of blogging software, allowing the team to treat each individual question as a separate entry with its own box.

The format also allows readers to pose follow-up questions on topics that pique their curiosity. Since funding for the project was limited — it began with no budget — Pierce and her team had to be creative. “We used our in-house information technology resources to help us develop the site,” she says. “And we used freeware we found to develop the actual pages.”

The questions were compiled by public information staff members, who researched and wrote the answers, but her team often sent questions and answers to staff engineers and hydrologists to confirm the informa-tion they were preparing to share. “It was pretty much a six-month proj-ect of collecting the questions, refining the answers, and then getting the

material vetted and approved,” says Pierce. “It was a learning process. We have an incredi-bly educated staff that has helped educate our depart-ment so we can answer the public’s questions.”

The team focused on keeping the answers under-standable for the average reader. “It may be a little ele-mentary for some adults, but for the most part it is geared

to people 14 or 15 and up,” Pierce says. The authority uses the “Major Ri vers” program developed with other Texas authorities to educate younger students about water issues, but the Water School is focused on junior high students and up.

More than the basics

The Water School is broken into 20 categories, beginning with a basic section that answers questions about the Brazos River Authority itself. The site can be easily updated. As of early May, Pierce says, “We have 215 entries and growing.”

The site includes an internal search feature that allows users to quickly track down specific topics that might have brought them to the Water School. Many answers also include illustrations to help visually explain everything from the broad swath of the Brazos River basin to the operations of a water treatment plant and the basic water cycle.

The IT department is installing Google Analytics on the Water School site, so Pierce hasn’t had a way to take virtual attendance until now. But she does know that close to 50 people have called with further questions after visiting the site, and some questions have prompted additions to the curriculum.

Compiling the Water School was an arduous task, but Pierce believes it was worth the effort: “The need for the public to understand the impor-tance of water in our daily lives is essential. With the rate of growth in the region, the state could run out of water in this basin by 2050 if we don’t focus on this resource.” wso

WSO welcomes stories about your public information and education efforts for future “Winning them Over” articles. Send your suggestions to [email protected] or call 877/953-3301.

Illustrations on the online Water School, such as the basic water cycle, help visually explain topics.


Since space was limited, MWH recommended Superpulsator technol-ogy (Infilco Degremont), which combines flocculation and coagulation in a single tank. There is no need for additional sludge collection and removal facilities, and there are few moving parts. The existing settling tanks were converted to a residual holding tank, and the existing back-wash wastewater holding tank was converted to the backwash water tank.

The Superpulsator unit is an upflow system that combines sludge-blanket flocculation with inclined plate settling. Chemically dosed raw water enters a high-rate flocculation tank, then flows by gravity to a sealed vacuum chamber that discharges the water to laterals at the bottom of the reactor. A pump creates a vacuum in the chamber, causing the water level to rise to a predetermined height.

A timer actuates an inlet valve on the chamber to open quickly so that the water stored in the chamber drains rapidly into the bottom of the dis-tribution system. This discharge creates a pulsating action, while the sludge blanket expands in the reactor.

As the water moves upward in the reactor, it starts to flocculate. A sys-tem of parallel plates inclined at 60 degrees enhances clarification. The upper level of the sludge blanket is controlled by overflow into a sludge concentrator, where the excess sludge is thickened before discharge. Above the inclined plates, the clarified water is collected through a set of submerged laterals.

To the test

The operators and laboratory technician were involved with the Super-

pulsator system pilot study and performed tests on incoming and finished water samples with laboratory analysts from Infilco Degremont. Says Skinner, “Because the operators learned quickly, this was the first loca-tion for an Infilco pilot study that successfully used and educated plant personnel in operating a pilot plant without the need for constant on-site Infilco staff.” Besides the Superpulsator system, plant equipment includes:

• Ferric chloride, caustic soda, fluoride and orthophosphate chemical feed pumps (Watson-Marlow)

• PolyBlend chemical feed pumps (Siemens Water Technologies)• Liquid chemical transfer pumps (Iwaki - Walchem)• Chlorine feed system (Siemens Water Technologies)• Powdered activated carbon dry chemical feed (MERRICK Industries)• In-line InstoMixers (Walker Process Equipment)• Lightnin Rapid Mixers (SPX Flow Technology)• Dual-media filters and filter underdrain system (Leopold – a Xylem Brand)• Electric operating valves and rate-of-flow control valves (Rotork)• PLC SCADA system (Allen-Bradley/Rockwell Automation)• Computer-controlled plant operating system (Rockwell Automation)• Flowmeters (Yokogawa)• Continuous pH, chlorine, fluoride and turbidity meters (Hach)

Transition challengesAt the startup of the new plant, some operators were excited, while

others were intimidated by the computer-controlled technology, Skinner recalls. The old lime softening plant used computer entries only for state reports and records; every operation was a hands-on control system. Operators walked from room to room and building to building to operate the plant and maintain levels in four water distribution systems.

With the new system, operators were worried that a wrong click of the computer mouse would hurt water quality or create an overflow some-where. One plant operator never owned a computer and had to learn all the basics before operating the new plant.

“It was very difficult for this operator to download all this new infor-mation at once,” recalls Skinner. “The staff pitched in a little extra every day to work with him. He got up to speed with reassurance that the rest of the staff would help out when needed.”

Four to six weeks before startup, equipment vendors conducted class-room and hands-on training for the chemical pumps, powdered activated carbon, flow valves and controllers. They covered flow rate adjustment and chemical mixture preparation.

“Two weeks of vendor training on the SCADA system helped transi-tion the operators over to computer command and live continuous data feedback,” says Skinner. “Training also included identifying and apply-ing the individual PLC module components.” Operators relied heavily on the O&M manual.

Bill Skinner, water department assistant superintendent.

Operator John Gentile in the control room.

“It was easier to read the instructions step -by-step and mouse-click-by-mouse-click simultaneously for some tasks, just as someone would do for installing computer software on a home computer, until the task became routine,” says Skinner.

The transition would have been easier if not for the power outages that started three days after the plant went online. The outages resulted from wind damage, power substation failures, a residential house fi re and a downed telephone pole. There were seven outages in the fi rst fi ve weeks of operation, the longest lasting 13 hours.

Fortunately, the plant had an emergency generator as mandated by the Ohio EPA. “The plant infl uent pumps, electric fi lter control valves and chemical metering pumps can run on generator power, but in manual mode,” says Skinner. “So, the operators have to go out and tie them into the SCADA fl ow pace mode again and check to make sure they are run-ning properly.”

Showing initiative

Skinner is fortunate to have self-motivated employees. Assistant oper-ator George Kovach modifi ed the clarifi ed water collection laterals so that they are self cleaning. Previously, the laterals were cleaned with a pool brush on an extension pole. The brush was fl at and the surface of the col-lection lateral is round.

Kovach took a small link chain and mounted it between the tips of an old Y-shaped pool skimming net brace after removing the tattered net. Now, the chain molds to the rounded shape of the collection lateral as it glides across the surface and gently pushes away any fl oc.

Operators designed a device to clean the Superpulsator vacuum cham-ber’s vertical water level indicator sight tube. The clarifi er water rises in the 1.5-inch-diameter clear tube equal to the water level in the vacuum chamber.

“It’s important to view the water rising and falling in the tube from the pulsing action,” says Skinner. “The tube is glued into position, since it

must remain airtight to operate properly, so it’s very diffi cult to clean.”Skinner and chief operator Rocky Zinno soldered a torpedo tip on one

end of a U-shaped 0.5-inch copper pipe and a garden hose adaptor on the other end. Operator John Gentile soldered a two-inch-diameter labora-tory bottle brush onto the tip of the torpedo end and drilled eight stag-gered small holes below the tip of the torpedo to provide water scouring as the brush slides up and down inside the tube.

Better quality

With diligent maintenance and the improved technology, the new plant has enhanced fi nished water quality:

• 45 percent total organic carbon (TOC) removal in 2011, versus 20.7 percent in 2006.

• Clarifi ed water turbidity to the fi lters at 0.091 to 0.235 NTU in 2011, versus 0.800 to 1.670 NTU in 2006.

• Combined fi lter turbidity at 0.023 to 0.067 NTU in 2011, versus 0.160 to 0.270 NTU in 2006.

Trihalomethane (THM) levels in 2011 were less than half the 2006 levels, as the Superpulsator system coagulant (ferric chloride) significantly reduced TOC. Lowering the pH in the distribution systems by using orthophosphate instead of lime coating for corrosion control also helped reduce THM.

EXPERIENCED TEAMEleven employees keep the Steubenville Water Filtration Plant

running smoothly. Three have 17 years’ experience at the plant,

including assistant superintendent Bill Skinner, one of the original four

operators who started the new Superpulsator plant in August 2007. He

became chief operator three months later.

In November 2011, Skinner was promoted to assistant superintendent,

reporting to city manager Cathy Davison. He holds an Ohio Class III

water supply license and is working on Class IV. He’s also a basic water

instructor on the Operator Training Committee of Ohio and a member of

the AWWA.

Other operations team members are:

• Chief operator Rocky Zinno (Class I water supply, operational labo-

ratory license, two years with the plant)

• Laboratory technician Joe Bottegal (Class III water supply, analyst

laboratory, 17 years)

• Plant operators John Gentile (Class III water supply, operational

laboratory, 17 years); Mike Wigal (Class III water supply, operational

laboratory, Class III wastewater, six years); Michael Boone (Class II

water supply, operational laboratory, fi ve years); Chuck Smith (Class

I water supply, operational laboratory, Class II wastewater, one year)

• Assistant operators Garrett Jenkins (eight years); George Clinton

Kovach (fi ve years); Rick Crosier (three years); and Robert Fithen

(one year)

The water treatment plant appears on the far side of this reservoir, built in 1895.

“They use their ears as much as the eyes or nose, since we have noises we didn’t have

before ... You still have to use your senses and not just look at a computer screen all day.”BILL SKINNER


The new plant’s peristaltic chemical pumps are more accurate and reliable than the old high-maintenance volumetric and gravimetric dry chemical feeders. And, the Superpulsator clarifiers “operate themselves,” says Skinner. “The Allen-Bradley controller adjusts the vent valve timing to control the volume and timing of the pulsing, and it also controls excess sludge removal. There are reliable vacuum pumps that run 24 hours a day to supply the lift in the vacuum chamber.”

Easier on operators

New technology has made operators’ lives easier. “With the old plant, they had to manually adjust the chemical volume on every chemical feeder every time the water flow through the plant changed,” says Skin-ner. “With the SCADA, the flow pace automatically adjusts every chemi-cal feed throughout the plant.”

“The coagulant we use is 41 percent ferric chloride, but because we receive it in liquid form, a certain delivery might be 41.7 or 40.7. We can enter the exact figure in the SCADA, and this helps control the chemical application.”

Operators have become accustomed to the sights, smells and sounds of the new equipment. “They use their ears as much as the eyes or nose, since we have noises we didn’t have before,” says Skinner. “We have an air-operated valve with a compressor and vacuum pumps that run all the time, so you get used to hearing the vacuum chamber release and the swish of air. You still have to use your senses and not just look at a com-puter screen all day.”

This came in handy recently when operators heard air leaking from an air-operated solenoid valve that needed to be replaced. Occasionally,

the polymer diaphragm pumps experience reduced audible stroke knock-ing. Operators must take the pump apart, extract the hardened com-pressed polymer from the chamber, and check the balls, springs and effluent line before re-assembling the pump and placing it back into service.

Operator Michael Boone found a very small chlorine leak caused by a nearly invisible crack in the combined filter effluent chlorine line in an outdoor vault. “The efficient operation of any water plant requires the operators to have good sensory perception,” says Skinner.

Always improving

The operators better themselves by advancing to the next license grade. “They’re constantly learning and looking at new ways of doing things and finding better methods for running the plant,” says Skinner.

They have completed the basic water and advanced water courses offered by the Operator Training Committee of Ohio (OTCO). They also take the Sacramento State University operator training correspondence courses on different water treatment topics. “This is much more effective than seminars, since they are exposed to so much more information,” says Skinner.

In April 2008, eight months after startup, the plant team conducted a full-scale study with the Superpulsator clarifier and a filter to see if they could high-rate the system. “This was successful, and we were upgraded to a 7.5 mgd plant with a 6.0 mgd operating capacity, without having to build another Superpulsator or filter,” says Skinner.

In 2010, the plant upgraded to a second communication system, along with a new river pump station and transmission lines and four new distri-bution tanks. “Right now, we’re considering another full-scale Superpul-sator study to see if we can push our current plant production even higher to accommodate more water customers,” says Skinner. “If not, we have room to add an additional Superpulsator unit to meet future demand.”

With the current economy and limited infrastructure funding, that remains to be seen. “We’re experiencing the funding squeeze every water system currently feels to operate and maintain their systems,” says Skinner.

Nevertheless, the plant is solidly on course for a long life producing high-quality water for Steubenville and its surroundings. wso

Rocky Zinno, left, and Bill Skinner under the filter building in the pipe galley.

MORE INFO:

Hach Company800/227-4224www.hach.com

Infilco Degremont, Inc.800/446-1151www.degremont-technologies.com(See ad page 19)

Leopold – a Xylem Brand704/409-9700www.fbleopold.com(See ad page 2)

MERRICK Industries, Inc.850/265-3611www.merrick-inc.com(See ad page 29)

MWH Global303/533-1900brandwww.mwhglobal.com

Rockwell Automation414/382-2000www.rockwellautomation.com/industries/water

Rotork585/247-2304www.rotork.com

Siemens Water Technologies866/926-8420www.water.siemens.com

SPX Flow Technology800/252-5200www.spxft.com

Walchem508/429-1110www.walchem.com

Walker Process Equipment800/992-5537www.walker-process.com

Watson-Marlow Pumps Group800/282-8823www.wmpg.com

Yokogawa Corp Of America800/888-6400www.yokogawa.com


The Palmdale Water District, 60 miles north of Los Angeles, treats 30 to 35 mgd from the California State Water Project surface water and local surface water from the San Gabriel Mountains to serve a popu-lation of 152,000 and growing.

When the 1980s water treatment system began to show its age, the dis-trict looked for alternatives to deal with seasonal taste and odor issues and comply with the U.S. EPA Stage 2 Disinfectants and Disinfection Byproducts Rule (DBPR), designed to reduce total trihalomethanes (TTHM) and haloacetic acids (HAA).

The district was concerned about its ability to meet the Stage 2 require-ment for a locational running annual average of less than 80 µg/L at all locations within the distribution system. Starting in 2004, the district worked with the AWWA to evaluate several treatment methods, ulti-mately choosing treatment with granular activated carbon (GAC) as the most cost-effective way to resolve its challenges.

Pilot studies

The district operations and maintenance staff built a GAC pilot plant with six contactors and tested vendors’ samples of GAC made from bitu-minous coal, coconut and wood for their ability to remove total organic compounds (TOC).

Water from the combined filter effluent flowed into the top of each contactor and flowed out the bottom after traveling through a bed of GAC. The volume and flow were adjusted to achieve an empty bed contact time (EBCT) of 15 minutes for each contactor. Flowmeters on the dis-charge line of each contactor recorded the volume treated. Regular sam-ples from the pilot plant influent and the contactor effluents were analyzed for TOC, and paired samples were used with flow data to calculate the pounds of TOC removed.

For the pilot study, the staff considered the GAC in a contactor expended when its TOC removal capacity was reduced to 30 percent. This happened within weeks for wood- and coconut-based GACs but took nearly four months for three coal-based GACs. Testing showed that GAC manufactured from bituminous coal was the best suited to remove TOC from the State Water Project water.

Based on the pilot study, the district chose GAC as a cost-effective alternative for meeting state and EPA Stage 2 DBP requirements and for its potential to meet Stage 3 regulations, depending on their final form.

BRIGHTIDEAS

PRODUCT: | Granular activated carbon (GAC) treatmentMANUFACTURER: | Calgon Carbon Corp.USER: | Palmdale (Calif.) Water DistrictAPPLICATION: | Reduce total trihalomethane (TTHM); remove taste and odorBENEFITS: | Effective performance, low cost

An Adsorbing StoryGranular activated carbon helps a California water district increase treatment flexibility, resolve seasonal taste and odor issues, and comply with Stage 2 DBPR

BY LEO ZAPPA

The Palmdale Water District treatment facility produces up to 35 mgd for roughly 27,000 distribution points.

GAC contactors in action.

GAC contactors with protective covering at Palmdale Water District.

Full-scale performanceIn November 2008, the district commissioned a new treatment plant

designed by Carollo Engineers that uses GAC contactors primarily to reduce TTHM in the distribution system. The plant allows operators to blend State Water Project surface water and local surface water. It also allows them to bypass the system when appropriate, providing great flex-ibility to meet water-quality standards. Since startup, the entire filtered effluent production has been pumped through the GAC contactors. Graph 1 shows the average TTHM levels within the distribution system from Jan-uary 2008 to February 2010.

From January to October 2008, the average monthly TTHM was 54 µg/L. From January to October 2009, the average was 29 µg/L. The average TTHM from November 2008 to February 2010 was 28 µg/L. This meant GAC reduced TTHMs in the distribution system by 47 percent. Table 1 shows the system’s running annual averages for TTHMs from 2002 to 2010.

This improvement came despite a shift toward using more surface water: The system used 61 percent surface water in 2008 and 65 percent in 2009. This shift would tend to increase TTHMs, but in actuality, TTHM levels did not increase.

TOCs improved

Graph 2 shows raw water and plant effluent TOC from January 2008 through February 2010 and shows the sequencing of the GAC contactors. When a new contactor came online, the prior contactors remained in service.

The average TOC from January to October 2008, before GAC treat-ment, was 2.6 mg/L raw and 1.5 mg/L effluent, for an average reduction of 42 percent. From January to October 2009 with GAC treatment online, the average TOC was 2.2 mg/L raw and 0.8 mg/L effluent, for an average reduction of 64 percent.

The average TOC since introduction of GAC, from November 2008 to February 2010, was 2.3 mg/L raw and 0.7 mg/L effluent, for an average reduction of 70 percent. This shows that GAC treatment improved TOC reduction by 22 percentage points.

The GAC treatment also dealt effectively with a 17 percent increase in bromide in the raw water, from 230 µg/L for January through October 2008 to 270 µg/L for November 2008 through February 2010. With the GAC contactors online, the increase in TTHM that would otherwise be expected with higher bromides did not occur.

Cost analysis

Postfiltration GAC contactors have proven highly effective in reduc-ing TOC. The remaining issue for the Palmdale district is balancing the cost of treatment with achieving water-quality goals. The district has tried to create a rule of thumb that may help other utilities considering GAC. Looking at 26 months of operation using GAC contactors, the district cal-culated the cost per acre-foot of water treated at the current market price of GAC (Table 2). The pri-mary cost of GAC treat-ment has been the purchase of GAC media. Here is how operational changes in the district have affected the cost of treatment:

Coagulation. The addition of GAC for TOC removal means there is more flexibility in dosing primary coagulant: The district no longer must achieve high levels of TOC removal in the coagulation and sedimentation process. Instead, the staff can dose its primary coagulant strictly for tur-bidity removal, reducing dosage and lowering chemical costs.

Taste and odor control. Before GAC treatment, the district used powdered activated carbon (PAC) to reduce taste and odor issues related to algal blooms. Now PAC is no longer needed, and that reduces treat-ment cost by $4 to $7 per acre-foot.

Boosting. Filtered water now must be boosted to the GAC contactors adding to overall power consumption, but that cost seems to be offset by lower chemical costs.

GAC media usage. The district believes it can comply with Stage 2 DBPR with four to five change-outs of the eight contactors each year, costing $80 to $100 per acre-foot if fresh GAC is used. If custom reacti-vated GAC performs as well, the cost could be reduced to $60 to $75 per acre-foot. Reactivation also eliminates cost and long-term liability related to disposal. Custom reactivation also has an environmental bene-

Graph 1

Table 1

Table 2

Graph 2

(Continued on page 29)


Ultrafiltration systemThe TARGA II Hollow Fiber (HF)

ultrafiltration system from Koch Membrane Systems is cost-effec-tive for a variety of applications including drinking water require-ments. The hollow-fiber membranes provide greater than 4-log removal of bacteria, viruses, Cryptosporidium and Giardia. The units are certified by UL under ANSI/NSF 61 Drinking Water System Components. The membranes are LT2 compliant and fully automated. The membrane design is based on polyethersulfone (PES) chemistry to increase fiber tensile strength. 888/677-5624; www.kochmembrane.com.

Screen filter

A self-cleaning screen filterfrom Forsta Filters uses system pressure to clean itself. A rigid cyl-

inder screen strains particles, trap-ping debris on the inside. The buildup

causes differential pressure across the inlet and outlet. A controller monitors the filter and opens a flush valve

when it senses adequate pressure. This creates rapid flow through the internal cleaning apparatus, which vacuums buildup from the screen and expels it.

The backwash cycle does not require the entire system flow to stop and reverse. Instead, a point-of-suction backwash reverses flow across the screen only directly in front of suction nozzles. This allows the cleaning mechanism to scan and clean the screen incrementally without disrupt-ing the main flow through the filter. Single units accommodate flow rates up to 8,000 gpm. 888/936-7782; www.forstafilters.com.

Measuring principle

The spectro::lyser mea-suring principle from s::can Measuring Systems measures UV and visible spectrum radi-ation (UV-Vis). It quantifies changes in TOC or COD, helps identify several differentiated groups of organics, and can detect individual organic substances. It can distinguish between normal and abnormal organic composition using event detection sy stems, allowing treatment plants to create spectral fin-gerprints of incoming water. 888/694-3230; www.s-can.us.

Current meterThe Streaming Current Meter (SCM) from

IN USA helps water treatment facilities control water quality by measuring and regulating con-tinuous online coagulant dosage. The meter measures the charge on suspended particles. It is suited for measuring and controlling coagu-lant dosage in flocculation systems. It mini-mizes jar testing and zeta potential measurement in the lab and saves coagulant usage. 781/444-2829; www.inusacorp.com.

Membrane systemThe Aqua UltraFiltration membrane

system from Aqua-Aerobic Systems offers a compact T-rack design, zero-break fibers and no air scouring. The multibore fibers are made of poly-ethersulphone (PES) with seven cap-illaries per fiber for strength. The alternating top and bottom feed and inside-out filtration flow provides uniform filtrate and backwash flows to minimize plugging, chemical usage and cleaning frequency.

The membranes can be cleaned at a higher pH with caustic instead of chlorine. Smaller, uniform pores provide 6-log removal for bacteria and 4-log removal for viruses. The systems are suited to drinking water, reverse osmosis pre-treatment, industrial water treatment, tertiary wastewater treat-ment, and reuse applications. 800/940-5008; www.aqua-aerobic.com.

Laser nephelometer

The FilterTrak 660sc from Hach ensures that small changes in turbidity measurements accu-rately represent real turbidity events by detecting turbidity changes as low as 0.0003 NTU. Operators can detect impending filter breakthrough, delineate

filter ripening, and maximize effective filter run time. Using advanced laser optics and signal processing, the

instrument detects submicron particles that are often pre-cursors to larger particles. 800/227-4224; www.hach.com.

GAC pressure filtersWesTech granular activated car-

bon (GAC) pressure filters effectively remove low-molecular-weight contami-nants, especially dissolved organic compounds responsible for poor taste and odor in drinking water. In pre-treatment, the filters prolong the life and efficiency of demineralizing ion exchange resins and reverse osmosis membranes.

These filters utilize a pressure vessel, typically with a conical under-drain for convenient GAC media replacement. They are sized according to contact time and desired media replacement frequency. Filter piping for multiple units can be arranged to easily change flow paths between parallel flow, series (lead/lag or daisy chain) flow, or single-unit flow. 801/265-1000; www.westech-inc.com.

THM removal systemThe GridBee Floating Spray

Nozzle THM Removal Systemremoves all four types of regu-lated trihalomethanes from pota-ble water storage tanks and clearwells with flow rates up to 100 mgd. Scalable systems are custom-engineered according to

tank size and hydraulics and install with minimal infrastructure changes. 866/437-8076; www.medoraco.com/spray.

PRODUCT FOCUS: TREATMENT AND FILTRATIONBY MIKE SCHOBLASKA

Filter systemThe Lakeside MicroStar Filter

offers high quality filtration. Pro-cess water flows into the MicroStar drum and through the filter media. As the process water flows from the inside to the outside of the drum, the filter captures solids. At a predetermined water level, the backwash cleaning sequence automatically initiates, using a dual spray system. 630/837-5640; www.lakeside-equipment.com.

Filtration process

Kruger offers the ACTIFLO Carb process to enhance removal of natu-ral organic matter, taste and odor, endocrine disruptors and pesticides with the combined benefits of ballasted clarification and adsorption on powdered activated carbon (PAC). The process applies to both drinking water and wastewater. PAC is recycled within the process. The process is adaptable to changes in raw water quality. The process train can be used with or without PAC based on seasonal demands. 919/677-8310; www.krugerusa.com. wso

It’s your magazine. Tell your story.Send your ideas for future articles to [email protected]


Badger Meter donates to Water Buffalos group

Badger Meter donated $5,000 to the Water Buf-falos in support of their efforts to construct and maintain safe, reliable drinking water systems in developing countries. The Water Buffalos include more than 40 members from the global water and wastewater industry who share a passion for motorcycles and the belief that everyone deserves access to clean drink-ing water. Cindy Kransler, director of utility sales at Badger Meter, and Rob Fehl, product marketing manager, have been involved with the fun-draising group.

MWH Global sells MWH Laboratories to Eurofins

MWH Global, provider of strategic consulting, environmental engi-neering and construction services, sold MWH Laboratories to Eurofins Scientific, a leader in analytical testing support. MWH Laboratories, one of the largest water quality laboratories in the United States, provides technical services from its 34,000-square-foot facility in Monrovia, Calif. Eurofins has 170 laboratories in 32 countries. It will retain MWH’s man-agement and 100 employees, renaming the facility Eurofins Eaton Ana-lytical in honor of Dr. Andrew Eaton for his leadership in water quality and 32 years of service.

Pure Technologies appoints vice president

Pure Technologies appointed John J. Galleher Jr., P.E., vice president for its newly established U.S.-based regional office in San Diego. He has 18 years experience in the operation and maintenance of municipal water delivery systems.

Xylem presents Goulds scholarships

Xylem, through its Goulds Water Technology Professional Dealers Association, presented 14 $1,000 scholarships to students who live in the United States and Canada and whose parents are Gould Professional Dealers Association members. The recipients are Casey Zarger, Eliza-beth Kolodziejczak, Hannah McGovern, Caden Burk, Samatha Welch, Taven Robinson, Deandrea Vickery, Shay Steinbeisser, Cameron Croon-quist, Gabriel Jenson, Jeremy Schimmoeller, Allie Polohonki, Jenna Cassidy and Travis Clelland.

Drive Source expands Dynamatic website

Drive Source International expanded the company’s Dynamatic brand website, www.dynamatic.com. The site features testimonials and technology videos on the company’s adjustable-speed drive pump con-trols and Eddy Current electromagnetic drives for the water and wastewa-ter industry.

FCI analyzer receives Canadian approvalsThe Model FS10A analyzer flow switch/monitor from Fluid Compo-

nents International received FM and FMc Canadian approvals, making the device suitable for continuous flow verification applications that sup-port process analyzer sampling systems operating in hazardous plant areas in the United States, Canada and elsewhere. The approvals include nonincendive Class I, Division 2 Groups A, B, C, D; Class II Division 2 Groups E, F, G; and Class II T4@Ta=71 degrees C Type 4X.

Control Works relocates sales, engineering offices

Control Works, supplier of custom control panels, moved into its new sales and engineering offices at 400 Techne Center Drive, Suite 104, Milford, Ohio. Phone and fax numbers remain the same.

Oldham launches expanded website

Oldham, an Industrial Scientific company, launched an expanded website, www.oldhamgas.com. The site offers information on products, applications, custom system design, support and sustainability.

Mueller establishes technology center

Mueller Co. established a technology center in Chattanooga, Tenn. The center includes 30 engineers focusing on technologies to help utili-ties overcome current and future water infrastructure problems through improved conservation, safety and operational efficiency.

Yaskawa acquires Wermac Electric

The Drives & Motion Division of Yaskawa America acquired the business and operations of Wermac Electric Ltd. in Calgary, Alberta, Canada. Wermac has been a 25-year partner with Yaskawa. The new divi-sion will be known as Yaskawa Wermac and will be located at the former Wermac Electric facility in Calgary.

UV Pure Technologies launches website

UV Pure Technologies launched a new website, www.uvpure.com. The site offers a company overview, product and techni-cal information.

Grundfos receives NSF listing for drinking water safety

Grundfos North America attained the NSF/ANSI Standard 61 Annex drinking water safety listing for all pumping systems in its standard product range. The listing covers pumps and pumping systems designed for boosting water pressure in commercial buildings and water transfer in municipal applications.

Hydrovolts names senior advisor

Hydrovolts, producer of hydrokinetic turbines to generate renewable energy from water treatment plants, appointed Anil Shrikhandle senior

INDUSTRY NEWS

John J. Galleher Jr.

advisor. He will assist with strategic planning, raising growth capital, manufacturing and distribution partnerships, and overseas expansions, particularly in India and Asia.

WILO USA names director of engineering

WILO USA appointed Joe Melton director of engi-neering. He has been with WILO since 2005 and pre-viously was southeastern regional sales manager and national sales manager for the company’s water man-agement segment.

seepex completes building expansion

Pump manufacturer seepex, an Enon company, completed construc-tion of a 51,000-square-foot manufacturing addition to its Clark County (Enon, Ohio) headquarters. The company manufactures pumps for municipal water treatment facilities.

Blue-White receives patent for safety switch

Blue-White Industries was awarded U.S. patent 8,215,931 for its Peri-staltic Pump Safety Switch. The switch stops the pump when the front cover is removed, allowing the pump to only operate in the maintenance mode (a set rpm), protecting the operator while routine pump head main-tenance is performed. wso

Joe Melton

january 2013

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