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1986.05.06_TC_Minutes_SpecialTOWN OF HIGHLAND BEACH, FLORIDA Minutes of Meeting of Town Commission SPECIAL MEETING - Tuesday, May 6, 1986 12:30 P.M. A Special Meeting of the Town Commission was called to order by Mayor Edward J. Sullivan in the Town Commission Chambers at Town Hall. Also present were Vice Mayor Mary Louise G. Blosser and Town Commissioners John J. Basso, William A. Grier and Betty Jean Stewart. Also present were Town Manager Hugh D. Williams, Town Clerk Mary Ann Mariano, members of the general public. Mayor Sullivan noted that the purpose of the Special Meeting was to review the report received from Camp Dresser & McKee, the Town's engineers dated April 17, 1986, relating to trihalomethane control for the Highland Beach Water Treatment Plant. Mr. Jay Ameno, representing CDM was present. Mr. Ameno announced to the Town Commission that Robert Moresi, engineer who had authored the Town's report on capacity and water use, was no longer employed by CDM, however, the Water Resources Department at CDM would still be • submitting the Town's report in a timely manner. Mr. Ameno cited the report of April 17, 1986 (a copy of which report is attached to these Minutes. for reference) which listed alternative methods available in the current state of technology for trihalometh- ane control and offered to answer any questions. Mayor Sullivan summarized the methods noted in the report and the cost factors which were included in several of the methods, the most inex- pensive method being the chloramine method at a cost of approximately $10,000. Mr. Ameno suggested a combination of the chloramine system with a coagulation method. Commissioner Stewart requested information as to the cost factors in the coagulation method as well as how such a system worked. Mr. Ameno noted that the capital cost was low inasmuch as only feeding equipment and possibly a storage tank would be required. The day to day opera- tional costs would become a factor as it requires an additional chem- ical to remove precursors through the coagulation method. Also needed would be a metering flow pump, although the meter already at the plant could be utilized with a flow pacer. The chemical addition point would be in the raw water stage. Commissioner Stewart noted that there were no cost figures associated with each of the alternative methods addressed in the April 17, 1986 • report. Town Commission Special Meeting • May 6, 1986 Page 2 of 4 Mr. Ameno noted that the cost involved with the coagulation method would be approximately $20,000-$30,000 for equipment. Mr. Williams noted that although this method would be the least expensive to implement, the labor, chemical and maintenance costs involved would probably make it more expensive in the long run than other methods i.e. aeration. Commissioner Basso questioned the costs involved should the water useage be increased due to growth factors. Mr. Ameno stated that the implementation cost would be the same, however, the chemical useage would increase, thereby increasing the cost of operation. It was noted that the reverse osmosis method would encompass the replacement of the water plant at a cost of approximately $2,000,000 to facilitate this method. Mr. Ameno also noted that a cost analysis over a period of time would have to be made to determine the opera- tional costs of this system. It was pointed out that in the State of Florida, the reverse osmosis systems were becoming more popular and the costs of the operating plants were being reduced due to the increase in popularity. Although through the reverse osmosis system a lesser quality of water could be used, Mr. Ameno noted that the South • Florida Water Management District would frown on the Town using any water that would jeopardize the water table and increase the salt water intrusion problem in the surrounding areas. Mayor Sullivan noted that the report did not give any specific recom- mendations of CDM in favoring one method over another. Mr. Ameno noted that in order to make a specific recommendation, a further study to identify the capacity of the Town's raw water to form trihalomethanes and the specific plant involved. Each water plant has to be individually studied and cannot be based on factors from another plant. Commissioner Grier noted that the Town was above THM standards set for Boca Raton and Delray Beach, who use an ammonia treated system, and who aer below the set standards, and asked what the cost factors involved in a transition to this system would be. Mr. Ameno noted that this would involve the chloramine method cited, which had been earlier quoted at a cost of $60,000 - $90,000, based on manual and automatic systems. Mr. Ameno suggested a plant scale study to determine the most cost effective method for the reduction of trihalomethanes in the Town's water system, possibly by the coagulation method. Mr. Williams was concerned with finding the fastest, most inexpensive • way to reduce the THM factor in the water, without having to treat • Town Commission Special Meeting May 6, 1986 Page 3 of 4 with any additional chemicals, but using the most natural way i.e. air stripping. Mr. Williams recommended that a study be done to determine this fact. Mr. Ameno stated that there were a lot of unknown factors to be determined such as formation factors for trihalomethane before any recommendation could be made. These facts would have to be known before the designing of any system which would be cost effective and feasible for the Town, which would require study and extensive sampl- ing. Mr. Ameno noted that the feasible methods to analyze would be the coagulation method in conjunction with ammoniation. Commissioner Stewart stressed that if the Town were to change or modify its system, it should be compatible with Boca Raton and Delray Beach in case of any emergency. Mayor Sullivan left the meeting at 1:00 p.m. for another appointment. Mr. Ameno stated that such a study would take approximately 3-4 months to complete at an approximate cost of $20,000.00. Commissioner Grier noted that the study should focus on the ability of residents to pay, the availability of qualified personnel to handle • any changes made, and the immediate problems which need solving, rather than determining what may or may not happen in the future. Commissioner Grier further noted that the residents of Highland Beach were able to pay for the upgrading of their water system better than some of the other smaller communities. Commissioner Stewart noted that the residents in Highland Beach were already paying for filters and other devices for water treatment in their homes, according to a recent survey taken in Town. Commissioner Stewart also stated that any of the devices for home use did not take THM's out of the water according to recent articles on the subject. Mr. Ameno was advised by several members of the Town Commission of their dissatisfaction in the past in receiving reports late, and the forcefullness which has to be placed on CDM in order to get action and response to the Town Commission's directives. Mr. Ameno stated that he would submit a proposal for the study within approximately one week at which time the Town Commission will consider same. There being no further business to come before the Town Commission at this Special Meeting, it was adjourned at 1:20 p.m. • Town Commission Special Meeting May 6, 1986 Page 4 of 4 APPROVED: Edward J. ~SyJllivan, Mayor Mary ouise G. Blosser, Vice Mayor J /,n J sso, Co~;issioner Z/(/) ~. ~~ William A. Gr er Commissioner Bet Jean Stewart, Commissioner ATTEST: • ~ TOWN CLER DATE: ~~•-~~~ ATTACHMENT: C.D.M. REPORT (4/17/86) • #EC I VEa c. CAMP DRESSER a MdCEE INC. CDM ; 986 �M=n�, � .e»� , � � SVW pa» ,Mr., n+w"W"Sn eoaawam, R. L&Wwda* Floria. 7741-IM L .mss Board of Commissioners Town of Highland Beach 3614 South Ocean Boulevard Highland Beach, Florida 33431 .Attention: Mr. Hugh Williams - Town Manager RE: Trihalomethane Control for the Highland Beach Water Treatment Plant Dear Commissioners: In response to your request, this letter is an update of our letter of December 12, 1983. Enclosed for your use is a copy of the referenced letter. Trihalomethane (THM) samples have been taken in the distribution system and are approximately 2.5 times the maximum contaminant level of 100 micrograms per liter (ug /1). We would like to present a brief background on THM formation and a description of the technology currently available. GENERAL Trihalomethanes are defined in the EPA regulations as the sun of the concentrations of bromodichloromethane, dibromochloromethane, tribromomethane (bromoform) and trichioromethane (chloroform). this group of synthetic organic compounds is formed by the interaction of free chlorine through a complex series of reactions with naturally occurring compounds. These naturally occurring organic substances which react with chlorine to form THMs are generally referred to as precursors. Precursors are usually humic or fulvic substances which reach the water from decaying vegetation. These precursors are often, but not always, the compounds which impart color in South florida water supplies. The THM producing reaction can be summarized as follows: Organic + Free + (Bromide ion or = TRIHALOMETHANE Precursor Chlorine iodide ion) The reaction will continue in a water system as long as there are precursors and a free chlorine residual is available. If either bromide or iodide ions are absent, chloroform will be the THM formed. The actual levels of the THM formed in the finished water depends on a e : f YF jtw The Honorable Board of Commissioners CAMP DRESSER & McKEE INC. April 11, 1986 . Page 2 number of factors in addition to the treatment process. For example, if chlorine is used, the contact time and the chlorine dose will often have an effect on the level of THMs formed. From the simplified THM formation reaction presented, it can be seen that three general categories of THM control alternatives are possible: (1) Treatment modifications to reduce precursors prior to chlorination, (2) Use of an alternative disinfectant which will not react to form THMs, and (3) Treatment to reduce THM after formation. These factors must all be considered in the evaluation of THM control alternatives. The processes currently available within each general category are shown in Table 1. Several of the processes are simple solutions; however, most are encompassing and their applications crust be cost effective. This letter represents a brief description of each of the THM control processes. A more detailed discussion on THM reduction alternatives can be found in (4). Combinations of methods in two or even all three of the general approaches may be considered to reduce THMs while optimizing bacteriological control. For example, to meet THM regulations it may be necessary to reduce the precursor levels by optimized coagulation and use of an alternative disinfectant. Alternate disinfectants must be acceptable to the regulatory agencies and must maintain the bacteriological integrity of the distribution system. The THM removal alternatives first require the initial formation of as many THMs as possible prior to removal during the treatment process. All THM removal alternatives are capital intensive when applied to an existing plant. COAGULATION Coagulation traditionally is achieved by the addition of aluminum or iron salts for the removal of color, precursors, and organic and inorganic matter. Aluminum salts (alum), if not totally precipitated out in the plant, will carry over into the distribution system and quickly precipitate out in the pipes causing a serious reduction in carrying capacity due to increased friction losses. Ferric chloride along with a polymer is efficient in removing precursors and color. Coagulation can reduce color and precursors to a level that will require less chlorine for color bleaching and for maintaining a free residual in the distribution system. A lower chlorine dosage also will form lower THMs. If a high enough removal of precursors can be obtained by coagulation, a free chlorine residual may even be possible without exceeding the current THM regulation of 100 ug /1. The Honorable Board of Commissioners April 17, 1986 CAMP DRESSER b. McKEE INC. . Page 3 TABLE 1 TRIHALOMETHANE REDUCTION ALTERNATIVES I. Precursor Reduction A. Optimized coagulation B. Shift in chlorine feed point C. Powdered activated carbon D. Granular activated carbon E. Biologically activated carbon F. Synthetic resins G. Potassium permanganate H. Reverse osmosis I. Appropriate combination of A through H. II. Alternative Disinfectants . A. Free chlorine B. Combined chlorine (Chloramines) C. Chlorine dioxide D. Ozone E. Appropriate combinations and modifications of A through D. (Free chlorine in plant and chloramine residual in distribution system) III. THM Removal A. Synthetic resins B. Granular activated carbon C. Biologically activated carbon D. Aeration E. Appropriate combinations of A through D. IV. Appropriate Combinations of I, II and III • Ilk The Honorable Board of Commissioners CAMP DRESSER & McKEE INC. April 17, 1986 . Page 4 SHIFT IN CHLORINE FEED POINT Moving the chlorine feed point to post filtration will take advantage of the precursor removal abilities of the softening and filtration processes. However, in many plants chlorination after filtration does not provide sufficient contact time to ensure complete disinfection to meet regulatory agency standards. Any chlorination before this point should be kept well below breakpoint dosages to prevent free chlorine from reacting with the precursor. One of the disadvantages to this shift in chlorination points is that the color is not removed as efficiently. Experience and literature research indicate that this THM control mechanism alone has been applied more successfully at surface water treatment plants with alum or ferric salt coagulants than in softening plants with lime coagulation. It is advantageous to use a shift of chlorination points in conjunction with another of the available THM control alternatives. POWDERED ACTIVATED CARBON (PAC) PAC will remove THM precursors, THMs, other organics and perhaps some color; however, PAC is a high cost item and will remove THMs or their precursors only at high dosages. PAC can be introduced to the system prior to softening, but PAC adds carbon solids to the sludge recirculation and to . the sludge disposal process. A powdered activated carbon system will add substantial operation and maintenance costs to the water plant. GRANULAR ACTIVATED CARBON (GAC) GAC will remove THM precursors, THMs, other organics, and may remove some color. The efficiency of GAC for precursor removal is still questionable and usually requires site specific pilot studies for an accurate determination. GAC is usually installed as part of the filter media (filter capping) or in a separate process step such as GAC contactor columns. For existing plants, the former is usually less costly but sometimes impractical due to existing filter depths. With either arrange- ment, the initial cost of a GAC bed is high. The operation and maintenance costs associated with GAC treatment are also high. GAC has a tendency to promote bacterial growth on its surfaces and small chlorine dosages are commonly used to curtail such growth. The average life of the GAC for THM removal is short and after about six weeks the carbon has to be replaced with new or regenerated GAC. Regeneration of the GAC is a power intensive process which requires heating at either a location onsite, or a local facility capable of regeneration. THMs as a group are among organic compounds least readily removed by GAC adsorption. Its use in the Highland Beach system would not be anticipated unless an SOC problem develops in the raw water supply. The GAC process is found to be both expensive and difficult to operate effectively. BIOLOGICALLY ACTIVATED CARBON (BAC) • BAC is a new technology which originated in Europe. The water is usually pre- ozonized and then passed through a GAC bed. The ozone and dissolved oxygen which is added during ozonation maintain the bed in an aerobic The Honorable Board of Commissioners April 17, 1986 CAMP DRESSER & McKEE INC. . Page 5 condition. Organisms growing in the bed apparently continually activate the carbon as it is kept in service. As a result, the carbon is able to operate actively for a longer period than regular GAC beds without having to be regenerated outside the bed. Post - treatment with a strong disinfectant usually follows the BAC treatment step. The effect of the bacteria on precursor or THM removal is questionable and unproven. Obtaining regulatory approval of a process using aerobic bacteria in potable water would also be difficult in the United States. Many of the problems of maintaining the carbon are the same as for GAC, as well as having a new problem of maintaining a proper bacteriological colony. Because of the experimental nature of this process and the shortcomings listed above, BAC as a THM control alternative is not recommended. SYNTHETIC RESINS At the present time synthetic resins for precursor adsorption are unproven. Synthetic resins are specific to certain compounds which will be efficiently adsorbed. These compounds neutralize the resins' usefulness in removing the large range of organics which constitute precursors. Presently there are no plants operating using this type of treatment and most of the available data on resins is strictly experimental in nature. For these main reasons, synthetic resins are not deemed a feasible THM control alternative at this time. • POTASSIUM PERMANGANATE Potassium permanganate, KMnO is a good oxidant for organics and inorganics. Potassium permaNanate can reduce color and reduce the chlorine demand of the water; however, a disinfectant is still required. This process introduces manganese, which can create inorganic color in the system and complaints of pinkish color water if it is not effectively removed in the settling process. Potassium permanganate can also cause mud balls and clogging in the filters. This process requires very close monitoring of dosages. Several preliminary studies at local water treatment plants tested the use of potassium permanganate for color removal. The high dosages required for effective removal are impractical because of excessive chemical costs. Similar results are reported for THM precursor removal. Thus, potassium permangante is not considered as a realistic alternative to THM control. REVERSE OSMOSIS (RO) Reverse osmosis will remove organic color, THM precursors, hardness and other organic and inorganic materials. The development of low pressure RO systems has greatly reduced the operational cost for power of this type of system and can be used with the existing raw water supply. RO will provide a high quality water and eliminate the need for lime softening. A residual is still required in the distribution system and depending on the • efficiency of the RO system to remove THM precursors, a free chlorine residual may be utilized. This alternative has a high capital cost and high operating costs. The Honorable Board of Commissioners CAMP DRESSER & McKEE INC. April 17, 1986 Page 6 COMBINED CHLORINE (CHLORAMINES) A combined residual such as chloramines is easy to generate and has a persistent residual that can be maintained in the distribution system. Chloramines_ are formed by combining ammonia with free chlorine. To stop the THM formation, ammonia can be added, after a free chlorine residual is used to bleach out the color. The time a free chlorine residual is exposed to THM precursors must be limited so as not to exceed the MCL. A combined residual can also be accomplished by limiting the chlorine dose to that required by the naturally available ammonia in the raw water. Chloramine disinfection has been used extensively in the United States. Chloramines are not as strong a disinfectant as free chlorine, chlorine dioxde, or ozone. A much longer contact time is required with chloramines to attain the same level of disinfection as the other disinfectants. For this reason, chloramines for disinfection are often delegated a secondary role following one of the other more powerful disinfectants as the primary source of disinfection. There are several chemical reactions between these two compounds prior to breakpoint. After breakpoint, any added chlorine will exist as free residual. Initially, before reactions with ammonia, chlorine added to water will react to form hypochlorous and hydrochloric acid as follows: C1 + H = HOC] + HCl (Chlorine) + (Water) _ (Hypochlorous Acid) + (Hydrochloric Acid) Hypochlorous acid and ammonia react by a substitution process as follows: NH + HOCI NH + H (Ammonia) + (Hypochlorous Acid) _ (Monochloramine) + (Water) After this substitution reaction has occurred, the reactions of hypochlorous acid with chlorinated nitrogen compounds predominate. At this point, the amount of residual chlorine decreases. The simplified reaction is as follows: NH + HOC1 = NHC1 + H (Monochloramine) + (Hypochlorous Acid) _ (Dichloramine) + (Water) The final substitution of hypochlorous acid occurs only at high chlorine to ammonia ratios (15:1) as follows: NHC1 + HOC] = NCI + H 0 (Dichloramige) + (Hypochlorous Acid) _ (Trichldamine) + ( Water) Trichloramine, or nitrogen trichloride, is a very unstable gas. It is an eye irritant, odorous and corrosive and thus undesirable in the water • distribution system. The formation of trichloramine is the last reaction before breakpoint and, as previously stated, any additional chlorine added after breakpoint will be in a free chlorine residual. The Honorable Board of Commissioners April 17, 1986 CAMP DRESSER S McKEE INC. Page 7 A free chlorine residual exists in two forms, hypochlorous acid in lower pH waters and the hypochlorite ion in high pH waters. The balance of each is pH dependent. The hypochlorite ion will be the predominant free chlorine residual at pH values in excess of 9. As a disinfectant, the hypochlorite ion is not as strong as hypochlorous acid and just slightly more effective than monochloramine. CHLORINE DIOXIDE Chlorine dioxide, CIO 21 is usually more effective for taste and odor removal than chlorine. It is both a strong disinfectant and a strong oxidant which does not produce THMs by itself. Chlorine dioxide is a yellow -green gas that must be generated onsite by combining chlorine, water, and sodium chlorite. The suppliers of sodium chlorite are limited. The only domestic manufacturer of the product is the Olin Chemical Company. This could lead to a lack of competitive bidding for sale of the base chemical. One means of generating the chlorine dioxide involves a two -step reaction between hypochlorite solution with an acid such as hydrochloric and the products then reacting with sodium chlorite (NaC10 A more common means of chlorine dioxide generation is usually accomplished by adding chlorine solution from a chlorinator to a solution of sodium chlorite. The reaction is as follows: 2NaC10 + C1 2C10 + 2NACL . (Sodium Chlorite) (Chlorine) (Chlorine Dioxide) (Salt) During the generation process excess chlorine normally is used for efficiency and the resulting free chlorine residual could be available to react with the precursors and form THMs. EPA regulations currently require the monitoring of the finished water to prevent excess production of potentially toxic quantities of chlorites and chlorates which are formed as by- products of the chlorine dioxide reactions. The EPA recommends that the sum of the total residual concentrations of chlorine dioxide, chlorite, and chlorate in the finished water should not exceed 0.5 mg /l. The use of chlorine dioxide needs to be monitored closely. Waters with chlorite ion may be harmful to babies and pregnant women and at one time EPA proposed to limit the dose of C10 to 1.0 mg /1. This process does not as yet have complete acceptance by the FUR and its use in potable water treatment is not encouraged at this time by the regulatory agencies. OZONE Ozone is a more powerful disinfectant than chlorine or chlorine dioxide and does not produce THMs. Typical dosages are 1.0 to 3.0 mg /1 for disinfection. Ozone is very often effective for taste, odor, and color removal. Ozone has many pretreatment benefits and as a pretreatment step may be applicable to South Florida water systems. Schalekamp (3) and Rook (4) indicated that ozone reacts with the THM precursors making them less susceptible to reactions with chlorine and more susceptible to removal by coagulation and filtration. Ozone is reported to be more effective at a high pH which would be the case after the softening treatment process. The Honorable Board of Commissioners April 17, 1986 CAMP DRESSER 8 McKEE INC. Page 8 The Broward County Water and Wastewater Division performed a study on ozone treatment of the raw water at its District 1A WTP and found that ozone was ineffective by itself for color reduction (2). Ozone is a gas and must be generated on -site with the use of complex, energy- intensive equipment. Ozone does not produce a disinfectant residual, and therefore, a need for postdisinfection exists to maintain a residual in the distribution system. Chlorination commonly is used for this purpose after ozonation. The toxicity of reaction by- products from ozone and the organics in the water is still questionable. Some studies have shown that ozone will destroy some types of THM precursors while other studies have shown that ozone can oxidize nonprecursor organics into THM precursors. One disadvantage of ozone is the addition of high levels of oxygen to the water which could lead to corrosion in piping. AERATION Aeration will remove THMs, which are volatile organics, after they have been formed, by transferring them to the surrounding air; however, this may generate a negative public opinion from an air pollution standpoint. Unreacted precursors, which are nonvolatile, can pass through the aeration process and when being rechlorinated can generate THMs. This can be avoided by using a combined chlorine residual. Aeration will add carbon dioxide to high pH water and can result in the post - precipitation of . calcium carbonate. Some method for the prevention of entrainment of foreign particles in the water must also be considered in this process. Aeration is an efficient method of THM removal and should be kept in consideration. The location of this treatment process is after softening or filtration and after a long chlorine contact period to react as many precursors as possible. However, the exact air -to -water ratios required for effective THM removal is still uncertain and would require pilot testing. The ratio is a key parameter in selecting the size of aeration equipment and the associated costs. Because the aeration step would have to follow the THM formation stage, it could be costly to implement the aeration process in existing water plants' trains. SUMMARY There are three general categories for the control of THMs: (a) remove precursors before THMs form, (b) remove THMs after they form, or (c) use an alternate disinfectant that will not form THMs. Out of the THM precursor removal alternatives, improved coagulation and a shift in chlorine feed point may be applicable to the Highland Beach Water Plant. Optimized coagulation for color (precursor) removal may be successful along with shifting the point of chlorination downstream in the treatment process. Out of the THM removal alternatives, downstream aeration appears to be the only one that may merit further consideration. However, it would be costly . to implement in an existing plant and could create adverse water quality results in the distribution system. The Honorable Board of Commissioners April 17, 1986 CAMP DRESSER & McKEE INC. Page 9 All of the alternative disinfectants have advantages and disadvantages and some are more applicable than others. Pretreatment with ozone may be effective for color removal prior to coagulation and lime softening. Then, depending on precursor removal, free or combined chlorine residuals may be used in the distribution system. The plant may be able to use a high dosage of chlorine to bleach out the color followed by the addition of ammonia to stop THM formation and obtain a combined chlorine residual when the water leaves the plant. The use of chlorine dioxide alone may not be acceptable to the regulatory agencies and thus ranks as the least desirable of the choices for an alternate disinfectant. Furthermore, the above individual methods used alone may not be the solution to the control of THMs; however, a combination of alternatives may be effective. The chloramine alternative, as described herein, and in our previous letter, could probably place the THMs to below 100 ug /l; however, the EPA is proposing to lower the limit to the range of 25 to 50 ug /l in the near future. The approximate cost to implement the chloramine alternative is $100,000. Ozonation as a pretreatment process alternative for a 3 million gallon -a-day (Ml6D) plant assuming a 3 mg /1 ozone dosage would cost approximately $200,000. A free chlorine or chloramine residual for the distribution system would be required. . The reverse osmosis alternative for a 3-mgd water plant would have an approximate price tag of $2,000,000. However, this alternative would be a complete replacement of the existing water treatment plant. RO would still require a residual for the distribution system. Coagulation modifications to existing facilities should be investigated as they are low in capital cost, but can be high in operation and maintenance cost. All the options need to be researched and evaluated as they pertain to the Town of Highland Beach before a solution can be implemented. If you should have any questons, please contact our office. Very truly yours, CAMP DRESSER & McKEE INC. Jules J. Ameno Jr. P.E. JJA /ph File: 6636 -09 -WA cc: D. G. Munksgaard REFERENCES (1) Schalekamp, M., Experience in Switzerland with Ozone. Particularly in Connection with the Neutralization of en ca lly I desirable Elements Present in Water. (Paper delivered at the XM Convention, Anaheim, 1978). (2) Rook, J. J., Haloforms in Drinking Water. Journal American Water Works Association, 68, 168 (1976). (3) Ozonation Pilot Study Preliminary Test Report BCUD, Water and Wastewater Division, January 7, 1981. (4) Treatment Techniques for Controlling Trihalomethanes in Drinkin Miter by Symons, J. A., et. a ., U.S. EPA Cincinnati, OIL, 1981.