Handbook of Water and Wastewater Treatment Plant Operations - Chapter 2 potx

For example, in addition to their normal, routine, daily operating duties, operators may be called upon to make emergency repairs to systems e.g., making a welding repair to a vital piec

Water and Wastewater Operators and Their Roles

Our planet is shrouded in water, and yet 8 million children under the age of five will die this year from lack of safe water.

United Nations Environmental Program

2.1 WATER AND WASTEWATER

OPERATORS

To begin our discussion of water and wastewater

opera-tors, it is important that we point out a few significant

factors

• Employment as a water and wastewater operator

is concentrated in local government and private water supply and sanitary services companies

• Postsecondary training is increasingly an asset

as the number of regulated contaminants grows and treatment unit processes become more complex

• Operators must pass examinations certifying that they are capable of overseeing various treatment processes

• Operators have a relatively high incidence of on-the-job (OTJ) injuries

To properly operate a water treatment and distribution and/or a wastewater treatment and collection system

usu-ally requires a team of highly skilled personnel filling a

variety of job classifications Typical positions include

plant manager/plant superintendent, chief operator, lead

operator, operator, maintenance operator, distribution

and/or interceptor system technicians, assistant operators,

laboratory professionals, and clerical personnel, to list just

a few

Beyond the distinct job classification titles, over the years those operating water and wastewater plants have

been called by a variety of titles These include water

jockey, practitioner of water, purveyor of water, sewer rat,

or just plain water or wastewater operator Based on our

experience we have come up with a title that perhaps more

closely characterizes what the water and wastewater

oper-ator really is: a jack-of-all-trades This characterization

seems only fitting when you take into account the

knowl-edge and skills required of operators to properly perform

their assigned duties Moreover, operating the plant or

distribution/collection system is one thing; taking sam-ples, operating equipment, monitoring conditions, and determining settings for chemical feed systems and high-pressure pumps, along with performing laboratory tests and recording the results in the plant daily operating log

is another

It is, however, the non-typical functions, the diverse functions, and the off-the-wall functions that cause us to describe operators as jacks-of-all-trades For example, in addition to their normal, routine, daily operating duties, operators may be called upon to make emergency repairs

to systems (e.g., making a welding repair to a vital piece

of machinery to keep the plant or unit process on line), perform material handling operations, make chemical additions to process flow; respond to hazardous materials emergencies, make confined space entries, perform site landscaping duties, and carry out several other assorted functions Remember, the plant operator’s job is to keep the plant running and to make permit Keeping the plant running, the flow flowing, and making permit — no matter what — requires not only talent but also the performance

of a wide range of functions, many of which are not called for in written job descriptions.1

2.2 SETTING THE RECORD STRAIGHT

Based on our experience, we have found that most people either have a preconceived notion as to what water and wastewater operations are all about, or they have nary a clue On the one hand, we understand that clean water is essential for everyday life Moreover, we have at least a vague concept that water treatment plants and water oper-ators treat water to make it safe for consumption On the other hand, when it comes to wastewater treatment and system operations, many of us have an ingrained image

of a sewer system managed and run by a bunch of sewer rats Others give wastewater and its treatment and the folks who treat it no thought at all (that is, unless they are irate ratepayers upset at the cost of wastewater service) Typically, the average person has other misconcep-tions about water and wastewater operamisconcep-tions For example, very few people can identify the exact source supply of their drinking water Is it pumped from wells, rivers, or streams to water treatment plants? Similarly, where is it treated and distributed to customers? The average person

is clueless as to the ultimate fate of wastewater Once the

2

toilet is flushed, it is out of sight out of mind and that is

that

Beyond the few functions we have pointed out up to

this point, what exactly is it those water and wastewater

operators, the 90,000+ jacks-of-all-trades in the U.S do?

Operators in both water and wastewater treatment systems

control unit processes and equipment to remove or destroy

harmful materials, chemical compounds, and

microorgan-isms from the water They also control pumps, valves, and

other processing equipment (including a wide array of

computerized systems) to convey the water or wastewater

through the various treatment processes (unit processes),

and dispose (or reuse) of the removed solids (waste

mate-rials: sludge or biosolids) Operators also read, interpret,

and adjust meters and gauges to make sure plant

equip-ment and processes are working properly They operate

chemical-feeding devices, take samples of the water or

wastewater, perform chemical and biological laboratory

analyses, and adjust the amount of chemicals, such as

chlorine, in the water and wastestream They use a variety

of instruments to sample and measure water quality, and

common hand and power tools to make repairs and

adjust-ments Operators also make minor repairs to valves,

pumps, basic electrical equipment and other equipment

(Electrical work should only be accomplished by qualified

personnel.)

As mentioned, water and wastewater system operators

increasingly rely on computers to help monitor equipment,

store sampling results, make process-control decisions,

schedule and record maintenance activities, and produce

reports Computer-operated automatic sampling devices

are beginning to gain widespread acceptance and use in

both industries, especially at the larger facilities When a

system malfunction occurs, operators may use system

computers to determine the cause and the solution to the

problem

2.2.1 T HE C OMPUTER -L ITERATE J ACK

At many modern water and wastewater treatment plants

operators are required to perform skilled treatment plant

operations work and to monitor, operate, adjust and regulate

a computer-based treatment process In addition, the

opera-tor is also required to operate and moniopera-tor electrical,

mechanical, and electronic processing and security

equip-ment through central and remote terminal locations in a

solids processing, water purification or wastewater treatment

plant In those treatment facilities that are not completely or

partially automated, computer-controlled computers are

used in other applications, such as in clerical applications

and in a computer maintenance management system

(CMMS) The operator must be qualified to operate and

navigate such computer systems

Typical examples of the computer-literate operator’s work (for illustrative purposes only) are provided as follows:2

• Monitors, adjusts, starts, and stops automated water treatment processes and emergency response systems to maintain a safe and efficient water treatment operation; monitors treatment plant processing equipment and systems to identify malfunctions and their probable cause following prescribed procedures; places equip-ment in or out of service or redirects processes around failed equipment; following prescribed procedures monitors and starts process related equipment, such as boilers, to maintain process and permit objectives; refers difficult equip-ment maintenance problems and malfunctions

to supervisor; monitors the system through a process integrated control terminal or remote station terminal to assure control devices are making proper treatment adjustments; operates the central control terminal keyboard to perform backup adjustments to such treatment processes

as influent and effluent pumping, chemical feed, sedimentation, and disinfection; monitors spe-cific treatment processes and security systems

at assigned remote plant stations; observes and reviews terminal screen display of graphs, grids, charts and digital readouts to determine process efficiency; responds to visual and audible alarms and indicators that indicate deviations from normal treatment processes and chemical hazards; identifies false alarms and other indi-cators that do not require immediate response; alerts remote control locations to respond to alarms indicating trouble in that area; performs alarm investigations

• Switches over to semiautomatic or manual con-trol when the computer concon-trol system is not properly controlling the treatment process; off-scans a malfunctioning field sensor point and inserts data obtained from field in order to maintain computer control; controls automated mechanical and electrical treatment processes through the computer keyboard when computer programs have failed; performs field tours to take readings when problems cannot be cor-rected through the computer keyboard; makes regular field tours of the plant to observe physical conditions; manually controls processes when necessary

• Determines and changes the amount of chemicals

to be added for the amount of water, waste-water, or biosolids to be treated; takes periodic samples of treated residuals, biosolids processing

products and by-products, clean water, or

wastewater for laboratory analysis; receives,

stores, handles and applies chemicals and other

supplies needed for operation of assigned

sta-tion; maintains inventory records of suppliers

on hand and quantities used; prepares and

sub-mits daily shift operational reports; records

daily activities in plant operation log, computer

database or from a computer terminal; changes

chemical feed tanks, chlorine cylinders, and

feed systems; flushes clogged feed and

sam-pling lines

• Notes any malfunctioning equipment; makes

minor adjustments when required; reports

major malfunctions to higher-level operator and

enters maintenance and related task information

into a CMMS and processes work requests for

skilled maintenance personnel

• Performs routine mechanical maintenance such

as packing valves, adjusting belts, and replacing

shear pins and air filters; lubricates equipment

by applying grease and adding oil; changes and

cleans strainers; drains condensate from

pres-sure vessels, gearboxes, and drip traps; performs

minor electrical maintenance such as replacing

bulbs and resetting low voltage circuit switches;

prepares equipment for maintenance crews by

unblocking pipelines, pumps, and isolating and

draining tanks; checks equipment as part of a

preventive and predictive maintenance program;

reports more complex mechanical-electrical

problems to supervisors

• Responds, in a safe manner, to chlorine leaks

and chemical spills in compliance with the

Occupational Safety and Health

Admimistra-tion’s (OSHA) Hazardous Waste Operational

and Emergency Response (29 CFR 1910.120)

requirements and with plant specific emergency

response procedures; participates in chlorine

and other chemical emergency response drills

• Prepares operational and maintenance reports

as required, including flow and treatment

infor-mation; changes charts and maintains recording

equipment; utilizes system and other software

packages to generate reports and charts and

graphs of flow and treatment status and trends;

maintains workplace housekeeping

2.2.2 P LANT O PERATORS AS E MERGENCY R ESPONDERS

As mentioned, occasionally operators must work under

emergency conditions Sometimes these emergency

con-ditions are operational and not necessarily life threatening

A good example occurs during a rain event when there

may be a temporary loss of electrical power and large

amounts of liquid waste flow into sewers, exceeding a plant’s treatment capacity Emergencies can also be caused

by conditions inside a plant, such as oxygen deficiency within a confined space or exposure to toxic and/or explo-sive off-gases such as hydrogen sulfide and methane To handle these conditions, operators are trained to make an emergency management response and use special safety equipment and procedures to protect co-workers, public health, the facility, and the environment During emergen-cies, operators may work under extreme pressure to correct problems as quickly as possible These periods may create dangerous working conditions; operators must be extremely careful and cautious

Operators who must aggressively respond to hazard-ous chemical leaks or spills (e.g., enter a chlorine gas filled room and install chlorine repair kit B on a damaged 1-ton cylinder to stop the leak) must possess a Hazardous Mate-rials (HAZMAT) emergency response technician 24-hour certification Additionally, many facilities, where elemen-tal chlorine is used for disinfection, odor control, or other process applications, require operators to possess an appropriate certified pesticide applicator training comple-tion certificate Because of OSHA’s specific confined space requirement whereby a standby rescue team for entrants must be available, many plants require operators

to hold and maintain cardiopulmonary resuscitation/first aid certification

waste-water facilities have substituted elemental chlo-rine with sodium or calcium hypochlorite, ozone, or ultraviolet irradiation because of the stringent requirements of OSHA’s Process Safety Management Standard (29 CFR 1910.119) and the U.S Environmental Protection Agency’s (EPA) Risk Management Program This is not the case in most water treatment operations In water treatment systems, elemen-tal chlorine is still employed because it provides chlorine residual that is important in maintain-ing safe drinkmaintain-ing water supplies, especially throughout lengthy distribution systems

2.2.3 O PERATOR D UTIES , N UMBERS ,

The specific duties of plant operators depend on the type and size of plant In smaller plants, one operator may control all machinery, perform sampling and lab analyses, keep records, handle customer complaints, troubleshoot and make repairs, or perform routine maintenance In some locations, operators may handle both water treat-ment and wastewater treattreat-ment operations In larger plants with many employees, operators may be more specialized and only monitor one unit process (e.g., a solids handling

operator who operates and monitors an incinerator) Along

with treatment operators, plant staffing may include

envi-ronmentalists, biologists, chemists, engineers, laboratory

technicians, maintenance operators, supervisors, clerical

help, and various assistants

In the U.S., notwithstanding a certain amount of

downsizing brought on by privatization activites,

employ-ment opportunities for water and wastewater operators

have increased in number The number of operators has

increased because of the ongoing construction of new

water and wastewater and solids handling facilities In

addition, operator jobs have increased because of water

pollution standards that have become increasingly more

stringent since adoption of two major federal environmental

regulations: The Clean Water Act of 1972 (and subsequent

amendments), which implemented a national system of

regulation on the discharge of pollutants, and the Safe

Drinking Water Act (SDWA) of 1974, which established

standards for drinking water

Operators are often hired in industrial facilities to

monitor or pretreat wastes before discharge to municipal

treatment plants These wastes must meet certain

mini-mum standards to ensure that they have been adequately

pretreated and will not damage municipal treatment

facil-ities Municipal water treatment plants also must meet

stringent drinking water standards This often means that

additional qualified staff members must be hired to monitor

and treat/remove specific contaminants Complicating the

problem is the fact that the list of contaminants regulated

by these regulations has grown over time For example,

the 1996 SDWA Amendments include standards for

mon-itoring Giardia and Cryptosporidium, two biological

organisms (protozoans) that cause health problems

Oper-ators must be familiar with the guidelines established by

federal regulations and how they affect their plant In

addition to federal regulations, operators must be aware

of any guidelines imposed by the state or locality in which

the treatment process operates

Another unique factor related to water and wastewater

operators is their working conditions Water and

waste-water treatment plant operators work indoors and outdoors

in all kinds of weather Operators’ work is physically

demanding and often is performed in unclean locations

(hence, the emanation of the descriptive but inappropriate

title, sewer rat) They are exposed to slippery walkways;

vapors; odors; heat; dust; and noise from motors, pumps,

engines, and generators They work with hazardous

chem-icals In water and wastewater plants, operators may be

exposed to many bacterial and viral conditions As

men-tioned, dangerous gases, such as methane and hydrogen

sulfide, could be present so they need to use proper safety

gear

Operators generally work a 5-day, 40-hour week

However, many treatment plants are in operation 24/7, and

operators may have to work nights, weekends, holidays,

or rotating shifts Some overtime is occasionally required

in emergencies

Over the years, statistical reports have related histor-ical evidence showing that the water and wastewater industry is an extremely unsafe occupational field This less than stellar safety performance has continued to dete-riorate even in the age of the Occupational Safety and Health Act of 1970

The question is why is the water and wastewater treat-ment industry’s OTJ injury rate so high? Several reasons help to explain this high injury rate First, all of the major classifications or hazards exist at water and wastewater treatment plants (typical exception radioactivity):

• Oxygen deficiency

• Physical injuries

• Toxic gases and vapors

• Infections

• Fire

• Explosion

• Electrocution Along with all the major classifications of hazards, other factors cause the high incidence of injury in the water and wastewater industry Some of these can be attributed to:

• Complex treatment systems

• Shift work

• New employees

• Liberal workers’ compensation laws

• Absence of safety laws

• Absence of safe work practices and safety programs

Experience has shown that a lack of well-managed safety programs and safe work practices are major factors causing the water and wastewater industry’s high inci-dence of OTJ injuries

2.3 OPERATOR CERTIFICATION/LICENSURE

A high school diploma or its equivalency usually is required as the entry-level credential to become a water or wastewater treatment plant operator-in-training Operators need mechanical aptitude and should be competent in basic mathematics, chemistry, and biology They must have the ability to apply data to formulas of treatment requirements, flow levels, and concentration levels Some basic familiar-ity with computers also is necessary because of the present trend toward computer-controlled equipment and more sophisticated instrumentation Certain operator positions, particularly in larger cities, are covered by civil service regulations Applicants for these positions may be required

to pass a written examination testing mathematics skills,

mechanical aptitude, and general intelligence

Because treatment operations are becoming more

complex, completion of an associate’s degree or 1-year

certificate program in water quality and wastewater

treat-ment technology is highly recommended These

creden-tials increase an applicant’s chances for both employment

and promotion Advanced training programs are offered

throughout the country They provide a good general

through advanced training on water and wastewater

treat-ment processes, as well as basic preparation for becoming

a licensed operator They also offer a wide range of

com-puter training courses

New water and wastewater operators-in-training

typ-ically start out as attendants or assistants and learn the

practical aspects of their job under the direction of an

experienced operator They learn by observing,

show-and-tell, and doing routine tasks These tasks can include

recording meter readings; taking samples of liquid waste

and sludge; and performing simple maintenance and repair

work on pumps, electrical motors, valves, and other plant

or system equipment Larger treatment plants generally

combine this OTJ training with formal classroom or

self-paced study programs Some large sanitation districts

operate their own 3- to 4-year apprenticeship schools In

some of these programs, each year of apprenticeship

school completed not only prepares the operator for the

next level of certification or licensure, but also satisfies a

requirement for advancement to the next higher pay grade

The SDWA Amendments of 1996, enforced by the

EPA, specify national minimum standards for certification

(licensure) and recertification of operators of community

and nontransient, noncommunity water systems As a

result, operators must pass an examination to certify that

they are capable of overseeing water and wastewater

treat-ment operations There are different levels of certification

depending on the operator’s experience and training

Higher certification levels qualify the operator for a wider

variety of treatment processes Certification requirements

vary by state and by size of treatment plants Although

relocation may mean having to become certified in a new

location, many states accept other states’ certifications

In an attempt to ensure the currentness of training and

qualifications and to improve operators’ skills and

knowl-edge, most state drinking water and water pollution

con-trol agencies offer on-going training courses These

courses cover principles of treatment processes and

pro-cess control methods, laboratory practices, maintenance

procedures, management skills, collection system

opera-tion, general safe work practices, chlorination procedures,

sedimentation, biological treatment, sludge/biosolids

treatment, biosolids land application and disposal, and

flow measurements Correspondence courses covering

both water and wastewater operations and preparation for

state licensure examinations are provided by various state and local agencies Many employers provide tuition assis-tance for formal college training

Whether received from formal or informal sources, training provided for or obtained by water and wastewater operators must include coverage of very specific sub-ject/topic areas Though much of their training is similar

or the same, Tables 2.1 and 2.2 list many of the specific specialized topics waterworks and wastewater operators are expected to have a fundamental knowledge

wastewater operators must have fundamental knowledge of basic science and math operations

crossover training or overlapping training is common practice

TABLE 2.1 Specialized Topics for Wastewater Operators

Troubleshooting techniques Recordkeeping

Rotating biological contactors Vacuum filtration

TABLE 2.2 Specialized Topics for Waterworks Operators

Chemical feeders — math Measuring and control

Coagulation — flocculation Public health

Basic electricity and controls Electric motors

General safe work practices Cross connection control and

backflow

2.4 CHAPTER REVIEW QUESTIONS

AND PROBLEMS

2.1 Briefly explain the causal factors behind the

high incidence of OTJ injuries for water and

wastewater operators

2.2 Why is computer literacy so important in

operating a modern water and wastewater

treatment system?

2.3 Define CMMS

2.4 List the necessary training requirement for

HAZMAT responders

2.5 Specify the national minimum standard for

certification (licensure) and recertification for

water and wastewater operators

REFERENCES

1 Spellman, F.R., Safe Work Practices for Wastewater Treatment Plants, 2nd ed., Technomic Publ., Lancaster,

PA, 2001, p 2.

2 Job description and requirements taken from compilation

of many requirements; many are from those described in

Access-ed May 15, 2002.