Water quality surveillance - ACS Publications

DEBLLT, water quality manage‘men, should be dynamic a t all levels of potential control. The levels of potential control can be coiisidered as: the wastewater source; a collection site where water from a number of sources may be treated; and the receiving waters (stream, lake) which handle the drainage from an area or region. For effective management a t the control levels, adequate information about water quality must be available. I n most situations continual information is necessary. This article is directed toward chemists or engineers interested in water quality surveillance and management and has an industrial point of view. The first two control levels above are “inside the fence” for industry and are recognized as an industrial management responsibility.

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Points of View

Contiol Agencies. The subject of water quality control and management is vested in the Environmental Protection Agency at the federal leyel. The major federal goal has been the development of overall objectives for water quality. There has also been a significant program of research and developmeiit to bring technology to a level where overall objectives might be obtained. Equating of objectives with technology is considered but not required in the federal position, and programs for water quality improvement could be implemented even though technology to accomplish the objective could lead t o costly solutions or might not be immediately available. The legal position of the enforcement efforts by EPA has been that of action after-the-fact. A situa-

ANALYTICAL CHEMISTRY, VOL. 44, NO. 8, JULY 1972

tion in water quality degradation must have developed and have been accurately detected before action can be taken. Currently, federal enforcement is moving toward a before-the-fact position through future legislation based on effluent quality standards and the existing permit system as implemented through the Refuse Act of 1899. \Tater quality control programs are presently in the hands of the states or regional authorities. Implementation is through permit systems that are after-the-fact for effluents predating the permit system and before-the-fact for more recent effluents. Federal enforcement presents itself when problems become interstate, or when governmental or citizen action within a State requests federal aid. Industry. The industrial position

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come. Any particular individual a t an industrial plant could consider a water quality control project from the point of view of intangihle benefits, but funding of an industrial project requires strong justification. The strongest incentive for industry to act is one that involves a direct enforcement order. Importance of Cooperation. The overall definition of water quality and water quality objectives in any particular region is difficult, and implementation of water quality control is largely empirical. Tberefore, it is necessary to look a t water quality from a systems point of view where the inputs to the system and the response of the system are correlated in a real time sense, and the ability to manage the water system is also developed in a real time sense. It seems impractical that the obis one which responds t o necessity and to legal requirements. Industry has long been aware of the necessity for water quality management and wastewater treatment and, therefore, has for many years invested in the technology of wastewater treatment. For the most part, this investment has been undertaken as an overhead function of research and development and generally has not been directed toward any profitable venture. T h e industrial response in the implementation of water quality control is most practically justified on the basis of a reduction of losses to improve efficiency and profit or meeting that which is legally required. It is not practical to consider that industry in general is strongly motivated by any other factors because industry is a careful balance between costs and in-

Data 100 computer terminal is used a t the U S . Geological Survey's Water Resources Division Central Laboratory at Salt Lake City for many accounting routines in the laboratory. including sample logging, iob definition, analytical computation and printing, and cost accounting and performance of statistical analyses on lab operations. This laboratory can perform about 290 different chemical tests. A computer terminal linked t o the USGS IBM 360-65in Washington, DC. controls much of the activity of the laboratory ANALYTICAL CHEMISTRY, VOL. 44, NO. 8, JULY 1972

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Report for Analytical Chemists

jectives of water quality management can he reached by any enforcement vs. reluctant response relationship. The nature of the prohlcm definition as well as the necessity to implement control on a real time basis demands that a cooperative effort be involved in water quality control and management. Status of Water Quality Surveillance

C.S. Geological Survey. The Watcr Resources Division of the U.S. Geological Survey ha6 puhlished data on national water quality survcillance since 1941 and currently handles about 80% of the federal effort in water quality snrveillance. Thc program carried out by the U.S. Geological Survey is largely a cooperative effort with othcr agencies both state and federal. The USGS has about 5000 active water quality stations. About 150 of the stations arc continnoiis, electronic monitoring stations which cxaminc multiple parameters. The continuous monitoring st,ations function up to 80% of the time, d i e r e good supervision and maintenancc are provided, hut are considerahly less reliable as the degree of suprrvision decreases. Data at the continuous monitoring stations arc recorded digitally on punclicd tape. The punched tapcs are transferred to a control officewhere the data are transcrihed and stored on magnetic tapes in a national data storage and retrieval system. Sampling stations for determining the quality of surface mater range from continuous recording of srlcctcd characteristics to intermittent recording and sample collection, dcpending on data ncedcd. T h c “traditional” approach in analysis of watcr has been to remove suspcnded solids or turbidity Tvhiclr may interfere with analytical dctcrminations. This approach of trcat,ing a difficult analytical prohleni may simplify analysis, hut it does not necessarily provide mcnningfnl mvironmcntal data. For instancc, certain n.atc,r quality constituents, especially some of the minor elements and organic componncls, arc significantly transported in streams either sorbed on 34A

or attached to suspended sediment. For such constituents the traditional analysis of a “clearwater” sample only may present a n erroneous, certainly incomplete, picture of the concentration or load in the stream. T o provide t,he most useful data in its monitoring programs, the U.S. Geological Survey is recognizing that minor elements and organic compounds in water can occur in two phases-dissolved or associated with sediment. The sediment can, .of course, he suspended or on the hed. Therefore, objectives of the USGS in sampling constituents associated with suspended sediment are: to define the content of the constituent in both the dissolved and suspended phases; to assess the relative significance of the two phases in the water sampled; and ultimately, to define the source, behavior, and fate of each constituent. I n all circumstances, samples should include the suspended phase. Analytical results from samples are placed on punched cards and translatcd to the Water Resources Division data storage system. Data from this system dump to t,he Storet System, which is the primary system for storage of all watcr qnality information.

The U S . Geological Survey considers that elapsed time from sample collection to final data in the storage system should ideally be about seven days; practically, data can reach the storage system in 10 days to two weeks. The slowest of the analytical procedures required sets the pace, such as determination of BOD or special handling for metals. T h e U S . Geological Survey has a pilot project located in Salt Lake City which provides automated analytical systems for analyses of samples collected in all of the Western states. Samples are obtained as grab samples and air shipped to Salt Lake City. Rormal freight handling of samples permits elapsed time from collection of sample to arrival in the laboratory to he less than 24 hr. The pilot effort utilizes an automated system for wet chemical analyses, titrations, and metal analyses by atomic absorption. It is expected that the analytical capacity will he of the order of 20,000 standard analyses per year within the present development of technology for antomatcd techniques and systems operations. Results of the Salt Lake City pilot project will determine the future organization of present

Fisher titralizers with potentiometric and photometric heads utilize automatic sampling to determine primarily carbonate, bicarbonate, and sometimes sulfate. This instrument can titrate 15-20 samplesfhr. printing the results on a paper tape which is keypunched and transmitted to the computer for computation

ANALYTICAL CHEMISTRY, VOL. 44. NO. 8, JULY 1972


USGS laboratory facilities t h a t serve the Eastern United States. ilnalytical capabilities of district offices of USGS now provide backup effort in mobile facilities which can provide specific surveillance of selected areas for short periods of time. T h e photographs that accompany this Report show some of the facilities of Salt Lake City's Central Laboratory of the USGS Water Resources Division. Driving forces for USGS surveillance of water quality in the past have been the information desired by planners in water resources development, managers of public water supply and industrial utilities. and by users of water for irrigation-largely supported through the Survey's unique State-Federal co-op programs. Those interests still exist. but the expanding interest in water quality is now related to public awareness of pollution problems. The USGS is not involved in enforcement actions or water quality management decisions except through requests to validate data obtained or data gathering for other agencies. Y a t e r quality data reported by V'SGS become public knowledge. Environmental Protection Agency. T h e Environmental Protection Agency (EPA) has an interest in water quality surveillance founded upon enforcement requirements. Through its Analytical Quality Control Laboratory, EPA has conducted a program which looks a t the current instrumental capabilities for monitoring of ivater quality and also operates three monitoring stations near Cincinnati. These stations h a r e been sophisticated to the point of utilizing satellite telemetry to transfer data. EPA utilizes data from continuous monitoring stations to examine trends in water quality and to determine if water quality standards are heing met. Data from monitoring stations are not considered to be the final answer in precise definitions of water quality for these reasons : The analysis of any sample must be based upon total sample. meaning both soluble and inqoluble materials found in the

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sample. Many automated analytical procedures require that the sample be preclarified to a significant degree for the protection of the analyzer. Therefore, the analyses obtained are biased by any removal of materials of interest through clarification. Automated monitoring stations usually require the transfer of a sample by pumping through a transfer line. It is difficult to acomplish this transfer without a detectable change in the character of the sample. Deposition on walls and pipes, changes in size of suspended solids, and absorption of soluble materials on walls of pipes may have a significant effect on the representative nature of the sample as delivered to the sensors of the monitoring system. From an admissible evidence point of view, recorded data by a monitoring system are difficult to qualify, because the status of operation of the monitoring station can only be testified to for those brief periods of time when direct supervision and calibration of the system are made. Therefore, currently, enforcement data by EPA are developed from manually collected samples. Utilization of monitoring data in enforcement actions is a practical consideration for the future, but as yet, it is untried. EPA considers that examination of flowing water in a stream does not represent a total approach to water quality. Sediment samples from the bottom of streams should be examined also. The sediments represent deposits from previous stream transport or precipitation of solids. If toxic materials are present in the sediment which may transfer into the food chain and hence t o aquatic life or may be lifted by turbulences to the main flow of the stream, the sediment is a hazard .to water quality. The analytical quality control laboratory of EPA is also very much concerned with the quality

of analytical data obtained mannally. The laboratory points out that producing reliable waste data requires careful application of the proper analytical methods, use of modern equipment, and an adequate program of quality control. T h e quality control program should provide checks on the reagents and gases used, the performance of the instrumentation, the care and skill of thc analyst, his ability to provide accurate results, and the proper reporting of the analytical answer. A formalized program to evaluate these variables and to establish the reliability of the data is highly desirable. Quality control charts, recording daily performance and monitoring the ontpnt of each analyst, are effective means of measuring and controlling the laboratory performance. A publication on the subject of analytical quality control entitled, “Handbook for Analytical Quality Control in Water and Wastewater Laboratories,” is available from the Environmental Pro-

tection Agency, Kational Environmental Research Center, Analytical Quality Control Laboratories, Cincinnati, OH 45268. Practical Orientation to Water Quality Surveillance. From the descriptions of the approach to water quality surveillance by USGS and EPA, the federal efforts in water quality surveillance to date have been largely after-the-fact and largely limited to historic trends. If monitoring data are to he used for successful water quality management, the data must be available and utilized in a real time sense. Unattended monitoring stations automated for a number of key parameters are useful to survey the broad picture of water quality and to indicate the need for closer management of water quality in certain areas. Data for close water quality management must he available immediately and focused on the problem area. Probably under current technology, this is best achieved by mobile laboratory facilities which

Most of the metals are determined by automated atomic absorption spectrophotometry a t the Central Laboratory. Technicon samplers and proportioning pumps are used to feed samples and other chemicals to the AA instrument. Each channel is capable of 3&50 determinationslhr. This section uses four instruments and during the test year (March 1. 1971, t o February 20, 197.3, performed 45.000 determinations with about 2.5 man years of effort

can he moved.close to inputs which potentially are degrading water quality. The required surveillance information can be collected over a short period of time by manual or automated equipment closely supervised by laboratory personnel. Industry. Successful water quality management by industry requires t h a t sources of potential pollutants be under close surveillance to insure t h a t pollution control is exercised before-the-fact rather than after-the-fact. Industry is a significant source of water-borne pollutants, and as the water quality objectives for surface waters are more stringently enforced, industry will need to have reliable control over wastewater discharge a t all times. Any adequate level of reliability in water quality management necessitates some degree of continuous monitoring of pollutional discharges. A practical industrial orientation to water quality surveillance can he visualized as follows: At this point in time, most industries have inventoried wastewater problems, but if an industry has not made an inventory, the basic questions to be answered are what, where, and how much. Usually, the approach is reversed. How much in general parameters is determined initially. Then, by examination of particular sources of discharges within an industry, the where is established. After identifying the where, the what is estahlished more specifically. The how much, where, and what can be evaluated over a period of time to establish trends and degrees of variability. Rased on the inventory of wastewater sources, elimination of wastewater at the source can he examined, and changes in processes, process equipment, or operating procedure may he implemented t o reduce wastewater discharges. During the evaluation of sources, the practicality of monitoring of wastewater quality a t the source can also be developed. I n general, monitoring for wastewater quality at, the source is less complicated than monitoring wastewater quality x f t w R number of process streams have been mixed. A t the source,


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acceptable water quality possibly may be defined in a simple yes or no evaluation, particularly where deviation from the norm in wastewater character is readily evident. Once at-source reductions in wastewater quantity have been implemented, a new inventory must be established which recognizes the residual quantities of wastewaters that require further treatment. Assuming that the wastewaters will he trcated collcctivcly, the inventory now should develop data as to how much in terms of pollutional parameters and flow. Variability in flow and parameters must he estahlishcd to a degrcc which is adequate as a basis for design of wastewater treatment facilities. Once the wastewater treatment facility is in operation, i t will he ncscssary to monitor the process in terms of inputs to the process, process kinetics, and the effluent from the proccss to insure t h a t process performance is bcing achieved and to insure that the effluent quality is in compliance. Summarizing the industrial orientation of a a t c r quality surveillance, thcrc is a sequence of ohjectives which arc plausihle evcnts in progressing from definition of wastewater prohlems to the discharge of an effluent which is reliably controlled to meet water quality objectives. The sequence is: an inventory to define how much, where, and what; after actions are taken to achieve practical elimination of wastewaters a t the source, a reinventory is required to quantitatively define residual pollutants which will require treatment. A specific ohjective must he the definition of a design basis for treatment facilities; after treatment facilities are placed in operation, water quality surveillance at process sources must minimize abnormal discharges to the treatment facilities; water quality snrveillance a t the treatment plant must establish control of the wastewater treatment process and insure that t,he effluent is in compliance with watcr quality ohjectivrs. Water Quality Surveillance Procedures

Industrial Wastewater and Peripheral Surveys. Wastewater sur38 A

veys for industrial plants usually begin with a peripheral survey in which all discharges from the plant property are examined for wastewater characteristics. Historically, the survey is done manually, or it may utilize composite samplers which collect samples over a 24-hr or shorter period. A composite sample has the disadvantage that it averages the characteristics of the wastewater in the sample and hides short-term variability. The degree of variability in wastewater characteristics is a key factor in interpreting the wastewater discharges. Hence, the peripheral survey generally should not be based on composite samples, hut rather should be based on the collection of a statistical population of grab samples. The analytical data from the samples can he examined statistically to define variability. The degree of variability present in wastewater discharges is important from the point of view that discharges to a flowing surface stream are not mixed significantly upon themselves in the receiving stream but are diluted or stratified in some plug flow manner by the flowing water of the receiving stream. Additionally, variability must enter into the design basis for

wastewater treatment facilities where i t is a key factor in sizing the treatment process to meet minimum quality objectives or in sizing an equalization facility to minimize variability. Continuous monitoring would provide the optimum information about variability, but monitoring is expensive and currently is not practical for all of the parameters of interest. Peripheral surveys should he carried out in significant detail to establish good definition of the wastewater discharge problems. Thcrefore, all parameters of conceivable interest should he examined. Branch Surveys. The objective in branch surveys is to divide the peripheral information into wastewater discharges from areas within the industrial plant. This is frequently done by selecting particular branch sewers which have contrihuted to the peripheral survey. T h e level of information sought in the branch survey need not he at the same depth as was involved in the peripheral survey. Selected parameters of major interest may hc utilized. Source Surveys. Based on information from hranch surveys, areas which contribute larger portions of the wastewater load may

Recent acquisition, by the USGA laboratory for the automatic determination of colorimetric tests, is the Coleman 124-D spectrophotometer. This instrument performs about 80-90 determinations in 20 min and prints the results on a digital tape for key punching and computer use. Further coupling of instruments with computers is planned to increase laboratory efficiency and use



require further examination t o pinpoint >uiircc> of particular diarli:irge-. General Look at Parameters of Water Quality

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pact of cumulative or chronic effects requires the service of an aquatic biologist to examine biological samples from the receiving waters . It is most important that industries be sensitive before-the-fact to discharge of inorganic or organic materials which might, by accumulation up the food chain or through water contact, establish chronic toxicity, carcinogenicity, or other subtly developed, but critical, impacts. Past episodes in water quality problems are a positive guide, but other information such as toxicological information determined on animals can raise a warning flag. Biological laboratory techniques exist for estimations of acute toxicity to fish and evaluation of fishflesh tainting by wastewaters. For industrial wastewaters t h a t have toxicity characteristics, the test for toxicity to fish should be applied to the treated effluents. It cannot be assumed that treatment to remove organic or inorganic materials will also reduce or eliminate toxicity by the wastewater. Fish-flesh tainting should be applied where commercial or sport fishing is practiced in the receiving waters. Emission spectroscopy on ashed or concentrated samples of solids from wastewaters provides a conTyenient analytical procedure which scans for the presence of metals of interest. At a lo^ cost, the results obtained provide identification and approximate concentrations to the few milligrams per liter level. Sophisticated emission spectroscopic instrumentation and sample concentration techniques can provide quantitative results to the microgram per liter level. Atomic absorption instrumentation has become the work horse for routine determination of metals. Concentrations as low as fractional milligrams per liter are practical with little if any sample preparation other than to maintain the metals in solution. Determination of trace organic chemicals in water is difficult, and that difficulty is an obvious deterrent to any routine or cursory examination. However, if organic materials which are possibly hazardous in trace quantities are po40A

Table l. Organic Compounds Identified as Contributing to Taste and Odor in Kanawha River“ Naphthalene Tetrali n Styrene Acetophenone Ethyl benzene Bis(2-chloroisopropyI) ether 2-Ethyl hexanol Bis(2-chloroethyl) ether Diisobutyl carbinol Phenyl methyl carbinol 2-Methyl-5-ethyl pyridine *A. A. Rosen, R. T. Skeel, and M. 6. Ettinger, “Relationship of River Water Odor to Specific Organic Contaminants,” J. Water Pollut. Contr. Fed., 35, 777 (1963).

tentially present in the wastewater, analytical techniques, such as thinlayer chromatography, gas-liquid chromatography, and mass spectroscopy, should be applied to establish the presence of the material and the remokal efficiency of any treatment process. The evaluation of taste and odor contributions to receiving waters by wastewaters is almost entirely subjective, because the nose and taste buds are the most sensitive sensors. There have been examinations of organic chemicals found in water in an effort to correlate compounds with taste and odor. Phenols and phenolic materials have been recognized for years as taste and odor contributors, particularly when chlorinated. On the Kanawha River, xhere a high density of organic chemical industry is located, carbon filter techniques for sample collection led in 1963 to the identification of the compounds in Table I as contributors to taste and odor. On the Mississippi River a t New Orleans, taste and odor are problems, and the organic compounds

Table 11. Total Organic Compounds Found in Carrollton Water Plant (New Orleans) Finished Water“ Acetone Acetophenone Benzene Bromobenzene Bromochlorobenzene Bromoform Bromophenyl phenyl ether (positional isomer?) Butyl benzene a-Camphanone Chlorobenzene Chloroethyl ether Chloroform Chloronitrobenzene Chloropyridine Dibromobenzene Dichlorobenzene (positional isomer) 1,2-DichIoroethane

Dichloroethyl ether Dimethoxy benzene 2,6-Dinitro toluene Endo-2-camphanol Ethyl benzene Exo-2-campha no1 Hexachlorobenzene 1-Isobrobenyl-4-isopropyl benzene (1,2 isomer) Isocyanic acid Methyl biphenyl Methyl chloride Nitrobenzene o-Methoxy phenol p-Menth-en-1-8-01 Tetrachloroethylene Toluene lI1,2-Trichloroethane Vinyl benzene

“EPA Report, “Industrial Pollution i n the Lower Mississippi River Basin (Louisiana),” prepared by Baton Rouge Facility, Surveillance and Analysis Division, Baton Rouge, LA, 1972.



in Table I1 have been detected. During wastewater surveys, odor thresholds determined by odor panels provide practical identification of odorous wastewater streams. Near the source where wastewater streams are not complex, a practical nose may identify sources and specific compounds which contribute to the odor. I n summary, the gross parameters which define pollutional load and characteristics should be supplemented by examination for metals, taste and odor, acute biological impact, and further examined for any suspected materials which might have a chronic or subtle ecological impact. The latter item really is concerned with the fact that “the guard must be up.” and successful surveillance is very much dependent upon the recognition that presence of a particular compound constitutes a problem.

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Automated Water Quality Monitoring

I n the near future when water quality objectives and enforcement demand good lvater quality that is reliably maintained, it will be necessary to have “real-time” information continually. I n most situations it is impractical to obtain such information manually, owing to the “real-time” requirement or to the cost involved. Therefore, monitoring instrumentation must be utilized. llonitoring data niay have adequate utility if obtained continually rather than continuously ; that is. an automated analytical system inay deliver a result every few seconds or minutes, and sequential interpretation of the result can indicate all occurrences of interest. ‘-Realtime” should be considered as a time frame which encompasses the, instant of undesirable occurrence through an ensuing period of time n.hen successful correction action is practical. Visualize wastewater discharged to R sewer. At a point down the sexvcr, a sample is taken into a transfer line introduced into an automated analytical instrument analyzer. The results are interpreted and acted upon. The elapsed time from problem to correction is the sum of:

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time of flow in the sewer from discharge point to sample point, time of flow in the transfer line, time required to analyze the sample, time required to interpret the data, time required to decide upon corrective action, time required to implement corrective action, and time required for effective corrective action. The overall objective in the action system may permit a time frame of hours if downstream buffering of any impact is adequate. If downstream buffering is absent, correction in seconds could be required. Automated monitoring has a practical definition which includes the conditions that: essentially continuous information is delivered ; manpower requirements and operating costs for maintenance, operation, and supervision are economically acceptable; capital investment is acceptable; the accuracy of results is acceptable; and reliable performance is achieved. Acceptable costs are related to the justification for monitoring information. From the industrial point of view, there are two major areas of justification: enforcement of water quality objectives requires continual information; or continual information is useful and practical in optimized control of production processes or other sources of raw material or product losses. The potential for monitoring in relation to enforcement of water quality criteria can be seen developing on the horizon, but for most situations, it is not here as yet. On the other hand, the time is correct for industrial management to start thinking about water quality monitoring. A practical approach may be to initiate a limited degree of monitoring directed toward detection of undesired discharges of materials to the sewer. The degree of monitoring could be adjusted in the future to meet enforcement or other situations. Monitoring technology and instrumentation has t o be classified as immature but developing. The higher level of maturity to date is related to surface water monitoring stations where the kinds of measurements are temperature, pH, conductivity, dissolved oxygen, oxi-

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dation-reduction potential, and chloride. Maturity of technology in surface water monitoring stations is the result of research and development projects by organizations such as ORSAKCO and by agencies of the federal government, chiefly USGS and EPA. The parameters utilized in surface mater monitoring have limited applicability to industrial wastewaters, particularly where the interest is in organics in water. I n the past years developments within industry have brought forth instruments which detect the presence of organics. The first of these was the total carbon instrument which determines carbon from both organic and inorganic constituents in water. I n principle, a small sample of Tvastewater is injected into a carrier gas stream which passes through a high-temperature furnace where organic carbon is converted to carbon dioxide by combustion in the presence of a catalyst. -4ny carbon dioxide or carbonates in the wastewater sample will exist as carbon dioxide after combustion-thus the name, total carbon. A second generation of instruments for general detection of organic constituents in water has developed. One provides total organic carbon by subtraction of independent measurements of total carbon and total inorganic carbon. Another instrument referred to as total oxygen demand detects the consumption of oxygen during combustion and, therefore, does not measure inorganic carbon, but inorganic reactions which involve the consumption or release of oxygen are detected. Continual introduction of samples, which have a volume of 20-40 pl, into one of the combustion-type analyzers involves the use of an automated injection valve. Protection of the valve requires that the sample be filtered or that any suspended particles be reduced to a suitable size. Filtration should not be practical if organic materials in the solids are of interest. The use of a small on-line homogenizer is possible, but it is not as yet a proyen practice. Total carbon, total organic carbon. and total oxygen demand in-

strnments are applicable to monitoring service. The operation and maintenance effort will he greater than that associated with less complex instrumentation such as a temperature monitor, but the value of the information can be worth the effort. Instrumentation is marketed which utilizes ultraviolet absorption for the detection of general organic materials in water (aromatic compounds, particularly). The information can be specific and quantitative if a single compound is involved and will be general and Icss specific if a mixture of compounds is involved. Application is relatively simple in t h a t a flowthru cell provides sample interface with the instrument. Instrumentation which automates the standard, wet-chemical procedures is available and can be applied to monitoring needs. I n the reflection of most experience, such instrumentation requires a significant level of att,ention. However, a second generation of automated wet-chemical instruments, which operate a t lower pump speed and have lower reagent consumption, offers improved performance for monitoring service. Where justified, sophist,ication in monitoring instrument,s may utilize on-strcam gas-liquid chromatography, mass spcctroscopy, and nuclear magnetic resonance. If identification of specific compounds a t low concentrations is the objcctivc, particularly where the cornpound is a hazardous organic material which contrihutes to subtle environmental problems, cont,inuous monitoring for the specific compounds may he required. An alternative approach would he to monitor close to the source with a sensitive, nonspecific instrument, automatically collect samples of questionahle discharges, and analyze thc samples for components of interest. Water quality management by industry mill require good information a t the source. At-the-source is generally the production unit and specific operations in the production unit. At-the-source control information may not need to be specific as to constituents or concentrations in the discharge. Opera44A

tional information must state whether the quality of wastewater is or is not acceptable and may be satisfied by a yes or no answer. Thus, monitoring a t the source is potentially less complicated than monitoring at a point down the sewer, and the time frame for corrective action should be smaller. Water Quality Surveillance Needs

The area of major concern has to be the potentially chronic and suhtly developed impacts which wastewater discharges may have on the ccology of receiving waters. The potential for such an impact dcfies measurement in any parametric sense. Thus, t,he attack on thc problem may he limited t o the recognition of compounds which may contribut,e to such problems. Additionally, a biologically based procedure for evaluation of the chronic impact potential of wastewaters before discharge is desirable. Pract,ical water quality management by industry requires optimization of at-the-source control. Development of monitoring instrumentation which can examine wast,ewater quality and providc information dircct,ly to process unit operators is a practical objective. More detailed examination of watcr quality necessitates more specific information about the compounds in water, and the information is needed on a “real-time” basis. A current list of compounds would include metals, nutrients (particularly phosphorous and nitrogen), insecticides, and herbicides. Improved laboratory procedures are needed, and of course, monitoring instrumentation is desired. Monitoring instrumentation in general is relatively immature as .of today. Many of the “old-line” parameters are not represented significantly in monitoring equipment: for example, biochemical stabilization, taste and odor, phenol ( a t low levels), cyanide, metals, oil, and grease. There is a need for additional and improved monitoring in-’ strumentation for general parameters. A specific ‘area of improvement is in packaging which provides more compact and portable monitoring systems better suited for monitoring of effluents and for


short-term monitoring of surface waters. Acknowledgment

Comments relative to the Environmental Protection Agency and water quality surveillancc were based on the assistance and information provided by Robert Booth of the Water Quality Office, Analytical Control Laboratory, Cincinnati, OH. Walton Durum, U.S. Geological Survey, Water Resources Division, Washington, DC, provided comments and information about USGS activities in water quality surveillance.

Vernon T. Stack, Jr., is President of Il‘cston a n d Stack, Inc., a wholly ou3ned subsidiary of R o y F . Weston,

Inc. Mr. Stack, who earned a BChE from North Carolina State College in 1949, has been involved in pollution work since that time. After working with the North Carolina State Board of Health in stream pollution, he held positions a t Union Carbide as project and group leader in waste disposal, industrial hygiene, and air pollution. His association with R o y F. Weston dates to 1969 when he was Vice President and Director of Research and Development. Mr. Stack has been directly involved in basic and applied research in the environmental sciences area and has developed sampling, measuring, and detecting devices for determining characteristics of process waste streams. H e holds several patents for analytical devices and has 42 publications in the field. M r . Stack is a member of the ACR, A I C h E , ISA, A S T M , Water Pollution Control Federation, and the American Academy of Environmental Engineers.

Water quality surveillance - ACS Publications

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