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HomeMy WebLinkAboutAquifers - Benefits of Protecting EvaluationEVALUATING THE BENEFITS DF PROTECTING AQUIFERS Framework and Problems Frieda Reitman The University of Connecticut Frieda Reitman Assistant Professor of Business Environment I~IBA P~ogram at Stamford School of Business Administration University of Connecticut Stamford, CT 06903 and Policy 203-322-8398 Prepared fop presentation at the Atlantic Economic Society Conference, Octobe~ 10, lgBO. The ao~k upon ~hich this paper is based was supported in part by funds p~ovided by the Office of Water Research and Technology Project No. 8-OI5-CONN, U. S. Department of the Interior, ~ashin9- ton, D.C., as authorized by the ~ate~ Research and Development Act of lg?8 (P.L. g5-457).. The opinions expressed are solely those of the author. I mould like to acknoaledge the help of my colleagues L. Fmankel and In. Huffmire, and my 9raduate assistant, L. Golub. Abstract The purposes of this paper are (1) to set up a framework for measuring the benefits of protecting aquifers, (2) to identify the problems of measuremont, and (3) to assess the advisability of undertaking the measurements. It has been proposed that communities prohibit all or some of the following activities on land over aquifers: landfills, lagoons, septic systems, storage and transfer of oil and gas, storage of road salt. will the benefits outweigh the costs? (1) The damages that will occur if the aquifer is not pro- tected must be assessed. First one must establish the relationship between the action to be prohibited and its ¢ffect on the quality of the water, and then the relationship between a change in quality and a change in use. If these indicate the probable elimination of the aquifer as a source of ~ater, alternative sources must be iden- tified: another aquifer, treatment of contaminated water, conser- vation. For each, estimates of cost ranges are needed. A discount rate must be selected. The lowest estimate if the "cost" of inaction or the "benefit" of protection. Nine other benefits can be iden- tified. (2)It is difficult to quantify relationships, but making some assumptions simplifies the task. "Drinking water quality" is used as a standard of "quality." Limiting consideration to public supplies of ~ater leads to the need for alternative supplies when quality falls below the standard. Estimates of the costs of alter- nate sources must be made on a case-by-case basis. Data indicate that conservation may be the lo,est cost alternative; alternative supplies may cost less than treatment. ~iost of the other benefits are not measurable or are very difficult to quantify. (3) If the 'technical components of the required estimates can be provided, and if the assumptions are acceptable, it appears reasonable to measure the major benefit of protecting aquifers the cost of replacing polluted ~ater supplies. The other benefits cannot be measured with accuracy, but would increase estimates to be used in comparison with costs. INTRODUCTION The purposes of this paper are (1) to set up a framework for measuring the bensfits of protecting aquifersI (groundmater), (2) to identify the problems of measurement, and (3) to assess the advisability of undertaking the measurements. The study discusses these items from the point of view of Connecticut. The study was undertaken because of interest in preserving the quality of our groundwater. Groundwater is the major source of mater reserves; 9? percent of the fresh liquid water on earth is in aquifers. If water requirements increase and/or if surface maters become polluted, additional sources are in the ground. ~oms areas of the country are concerned with the quantity of available groundwater. that is not a problem, in the near future. However, there is For the state of Connecticut as a whole, although some communities expect shortages increasing evidence of groundwater pollution, and that can be a problem. In Connecticut, spillage of oil introduced contamination into 50 aquifers between July lg?6 and juns 1977.2 Du~ing 1979, the tomn of Southington had to shut domn 3 of its 8 municipal d~inking water malls because of contamin- ation mith two industrial solvents.3 Students at the l~iddle School in Weston have had to drink bottled water on and off for seven years because of salt pollution of its drinking water.~ If the quality of aquifer mate~ is not protected , then adequate water may not be available when needed. 2 SUGGESTED RULES FOR PROTECTING AQUIFERS Groundwater may become polluted in several ways. Contaminants on or in the ground are carried by water as it travels through the ground into aquifers. These contaminants may be natural or may be deposited in the areas above aquifers or areas ~hich drain into aquifers.5 Groundwater may also become polluted from surface water; ~ithdra~als of water from aquifers by pumping may induce water from surrounding streams or nearby oceans. Once polluted, aquifers usually take a long time to clear naturally. To protect aquifers, it has been proposed that certain uses of land over aquifers should be regulated, prohibiting activities which may lead to pollution. The Federal Government has assumed responsibility for regulating the disposal of toxic materials. This paper assumes that toxic waste disposal' will be regulated so as to protect aquifers and addresses other contamination problems. In general, land use regulation (zoning) is undertaken by the local community. Since aquifers do not conform to community geographic borders, this may not Oe the appropriate jurisdiction; state or regional jurisdictions may be more appropriate. Proposals to protect groundwater include the following prohibitions on the usa of land over aquifers: Suggested Regulations 1. A ban on landfills 2. A ban on septic and industrial lagoons 3. A ban on septic systems 4. A ban on storage and transfer of oil and gas 5. A ban on storage of road salt 1. A ban on landfills. This means closing existing ones and barring ne~ ones. Even if toxic wastes are excluded ( and policing is adequate to insure this) seepage from landfills presents a potential danger to underground water. Even specially designed "secure" landfills may eventually leak; they should be located elsewhere. However, landfills cannot be closed unless alternative disposal sites ara available. Since most communities do not ~ish to accept the garbage of another community, appropriate siting of landfills is a problem. State intervention may be necessary. 2. A ban on septic and industrial lagoons. These are pits, pools and ponds providing on-site storage of liquid wastes. The~e are 39 septage lagoons in Connecticut, regulated by the Oepartment of Environmental Protection (OEP) ~ater Compliance Unit. These are potential sources of contamination if located on aquifer recharge areas. 3. A ban on septic systems. This implies sewering for all areas over aquifers. This may not be cost effective for areas with lo~ density population. It may be reasonable, however, for clusters of houses to include some amount of joint sewage treatment. Low density zoning over aquifers may be an alternative to an absolute b~n on septic systems. In addition, industry should be required to treat its effluent. 4. A ban on storage and transfer of oil and gas. Spills and leaks from storage and from pipelines are serious sources of contamination and may be undetected for years. In Norwalk such a leak ~as undetected in a 9overnmant buildin9 until high fuel costs led to an investigation of the excessive "uss" of fuel! ~ater in Colchester end Stafford Hollo~ has been contaminated by leaks. For residences, it may be desirable to soften the ban and permit storage of small amounts in corrosion resistant tanks.8 5. A ban covered~ on an The Department do on storage of road salt. impermeable surface share of Transportation already not necessarily.? Road salt should be stored runoff can be collected° does this; municipalities Associated ~ith these prohibitions are certain costs for the community, residents and industry. This additional regulation is desirable only if the benefits out,~eigh the costs. It is necessary therefore to assess the benefits of such regulation. FRAMEWORK FO~ ~IEASURING BENEFITS Recent concern ~ith environmental protection has lad to a number of studies concerned ~ith measuring the benefits of such protection.8 As far as can be ascertained, tecting aquifers has not been measured° One set of "benefits" is the damages occur the benefits of pro- (or "costs") that mill if the aquifer is not protected by the proposed regulations. 5 RELATIONSHIP BETWEEN ~ATER QUALITY AND '~A'fER USE Before these benefits can be assesed, it is necessary to have (1) a clear evaluation of the "environmental quality" to be protected, (2) a clearly expressed relationship between the activity to be regulated and its effect on environmental quality, and (3) another clearly expressed relat£onship between the change in environmental quality and its effect on the "use" of that environment.lOApplying these requirements to groundwater, we develop the follo~£ng: Oefinition of Water Quality The quality of water cannot be described simply on some scale From i to lO. It is "an n-dimensional vector of the rele- vant parameters.''lO Some important characteristics of aquifer the level of o~gen the level of suspended solids the level of coliform bacteria the temperatire the rate of flow the pH level. For each pollutant, a measure of contamination can be calculated. There are no measures of "trade-offs." Ideally, it would be desirable to be able to combine characteristics and get a quality "number." ~hat we have instead is a set of water quality standards. These have been in existence for surface ~ater for a number of years; in 1980 parallel standards for groundwater were developed,ll Quality classes.AA, A, B, C, and D have been distinguished. For each quality standard, a numerical or a descriptive limit is set for each ~ater characteristic. "AA" is drinking water quality; "A" may be of that quality. 6 Effect of Activities to be Regulated on ~ater Quality Ideally, for aquifers, one mould like to be able to relate each activity (such as thos~ listed abcve under proposed prohibitions) mith the specific degradation of aquifer mater mhich it causes. Since the relationships depend on the nature of the composition and topography of the ground (which affects the rate and direction of flo~) the nature and extent of the discharge - the amount of rainfall - the nature and extent of mithdra~als from the aquifer, no simple cause-and-effect numbers exist, it mould be useful if scientists could quantify a multi-variable relationship so that probability statements on cause-and-effect could be evaluated. It ~ould be useful if a table like the folloming could be devised, so that the entry of data in the blank spaces ~ou)d lead to specific ansmers as suggested: amt. of contaminantl (primary, secondary) (type of rock) mhich is ~ithdramn bo degraded belo~ probability that placed in a landfill, mhich is located in a recharge area over an aquifer mhich is of mith estimated flom of from (feet per yea~) mill cause the aquifer to (gals. per month) in years. The (,water quality class) (number) this mill happen in the given number of years (range, probability~ Effect of Change in Quality on Change in ~ater Use Next, it is necessary to relate water degradation to change use: ~hat changes in use mill occur if water becomes polluted? Factors Affecting Use of 1. The type of delivery ~yotem (public, private wells) 2. The type of contamination 3. The type of user (residential, industrial, agricultural, commerc£al 12 The typo of delivery system, public or private is important in assessing th~ effects. [n Connecticut, 84% of the people are served by a public ~ater company (either publicly or privately owned). 163 of the people are supplied by private ~alls. ~ public water company almost al~ays has more than one source of water, [Fa source becomes contaminated, a switch is possible. [fo private well becomes contaminated, the user generally has other available water source. He ~ust resort to bottled water hook up to a publ£c supply. fhe type and extentof contamination (organic matter, chemical, oils, salts) and the type of user and use residential - domestic - lamn metering industrial - for product - for cooling - for mashing agricultural commercial are also important in assossing the effects of chango in quality. For domestic use and for use as part of a food product, only drinking water quality is acceptable. Degradation below that quality means an alternative is necessary. For other uses the presence of some contaminants in specified amounts may not change the use of the wate~ at all. In between these extremes no are many other possibilities. For each water delivery system, for each use of meter~ a relationship between each contaminant and its probable affect on use needs to be quantified. THE ~AIN 8ENEFIT: AVOIDING THE COSTS OF ALTE~NA¥IVES rO USE OF PULLUTED ~ATER When the change in use of the water is identified it is necessar~ to consider the responses to the change and the costs of those responses. If the aquifer is likely to be eliminated as a source of water, there are two possibilities. The less likely is that the activity or use mill be discontinued; the more likely is that an alternative source of acceptable mater will be found. Alternative sources may be a) mater from another aquifer or from a stream, b) the treatment of contaminated mater and c) conservation which may permit certain uses of ~ater to continue undisturbed while others are curtailed. Each alter- native has its o~n range of costs, The lowest estimate of costs is the "damage" or "costs" of inaction or the "benefit" of protecting the aquifer. Since these costs ~ill be borne in the future, an appropriate disco~nt rate must be selected to obtain the present value to compare to the present costs of protection. OTHER BENEFITS Assessing the benefits of protecting aquifer water by costa of alternative mater supplies ignores the following the potential benefits~ Prevention of undesirable and/or costly events likely to occur if an aquifer is not protected 1. use of water with unidentified contaminants 2. use of water with levels of contaminants harmful only to some portion of the population (people mith allergies, children, elderly) 3. trauma involved with discovering "impure mater" and worrying about its implications. 4. costs involved in immediate reaction to such dis- covery (bringing in bottled water) 5. costs for damages done before discovery Desirable events likely to be fostered by protection 1. sense of well-being of population freedom of fear of contaminated mater 2. protection of all sources of water (including private) on ~n aquifer 3. benefits which may occur as use and discharge patterns change in response to amareness, regulation and price increases13 4. ability to sell 'pure' water to other communities which need it. PRUBLEMS OF ~EASUREMENT ~ssuming that the framework presented above is a reasonable one for examining the benefits of aquifer protection, it is necessary to see if it is possible to obtain sufficient data to actualIy msasure the benefits. RELATIONSHIP BETWEEN WATER QUALITY AND ~ATER USE in order to be able to quantify the benefits of protecting aquifers, it is necessary to make a number of simplifying assump- tion~. 1. Oefinition of water quality. It seems reasonable to use the water quality standards already established. Only aquifers of A or AA quality are likely to be candidates for protection. Identifying the aquifers and assessing their quality are projects ~hich are being conducted by the Depart- ment of Environmental Protection and the United States Geological Survey. This information is not yet available but should be obtainable. This information is not obtained ~ithout cost, but is needed for other programs, so it is not clear that the cost of information should be considered a cost 15 of protecting the aquifers by the rules suggested above. 2. Effect of activities to be regulated on ~ater quality. Et appears as though it sho~ld be possible to devise a taole such as suggested above to evaluate the effects on aquifers of siting landfills, lagoons, etc. on land over them. LeGrand proposed a "System for Evaluation of Contamination Potential of Some ~aste Disposal Sites." He identified five important factors: ~atar table level, distance from the contaminant to the ~ater, the gradient and rate of flo~ of ~ater, the eorption capacity of the soil and the permeability of the soil. For each factor he proposed a scale of points relating to various characteristics. The total of the points ~ould then indicate the probability of a particular deposit causing the contamination of groundwater at a particular location: 16 or more points indicatesalmost no probability 8 - 16 points indicate moderate probability less than 6 points indicates high probability of contamination. 18 This system is designed to predict contamination by "sewage, detergents, viruses and radioactive ~astes" ~hich"decrease in potency in time or by oxidation, chemical or physical sorption 17 and dilution through dispersion." The author stresses it should not ba used "in evaluation of disposal sites for mixed ~astes, such as those found in refuse dumps and sanitary land- fills, if the critical consideration is the movement of chemica! 18 ~astes that attenLJate slowly." if ~e assume that toxic waste disposal will be handled under other auspices, it should 19 be possible to adapt LeGrand's system. The information given by this system contamination. It does not evaluate the extent of tamination, if ~e assume that our major interest tion belo~ drinking ~ater quality rather than level of contamination, the probability of such should be ascertainable. 3. Effect of change in quality There are many interrelating factors is a probability of the co~- is in degrade- in a specific degradation on change in ~ater use. to consider, making it difficult, to quantify the relationships. Very few uses require the highest quality water. Most uses can utilize degraded water but the type of degradation matters. For example, ~ater mith corrosive contaminants could damage delicats machinery. ~aking several ~ssumptions makes the interrelationships manageable. (a) The first assumption is that only sources of public water systems are to be protected. Private ~ells are importan~ too. Often they are the only source available to the user. Contamina- tion can have serious consequences. However, there is no easy ~ay to evaluate the probable change in use each individual Hater source, ~hich may be or agricultural. In addition, if aquifers are protected, private wells over the same protected - an additional unmeasured benefit. (b) The second assumption is that the contaminant and its costs for residential, industrial supplying public syetems aquifers ~ould also be level of 12 concern is the drinking ~ater standard. This follows from assumption (a) since, under current practice, only one grade of water is deliversd by public systems. (c) The third assumption, ~hich follow from (a) and (0) is that if ~ater is degraded below drinking water quality other acceptable sources will be provided. THE ~AIN BENEFIT: AVOIDINC THE COSTS DF ALYERNAT~VES TO USE OF OOLLUTEO ~ATER Under these assumtions, the major measurable ben,fit of protecting aquifers now is avoiding the costs of providing alternativas later. Cost of Alternate Supplies The cost of bringing water from alternate sources depends on the availability, the dist~nre and ~he type of ground to be traversed. The order ofmagnitcde of these axpendit~Jrescan be inferred from the following estimates. (a) ~n 1979, three wells in ~o~:thington, Connecticut shut because of contamination with volatile organics. To 20 place the ~ater, the company leased a ~ell and built a new ~ell. The cost of the leased well ~as $1,000 a month rent and $6,000 to set up the ~sll~hich involved laying 300 feet of pipe and moving treatment equipment from other ~ells. The capital cost of the ne~ ~ell was ~500,000 which in- cluded the testing and purchase of the land and premium payment for rapid construction through the ~inter. To date there has been a 50% increase in ~ater rates. In the future, price demanded for per month now being if water supplies become more scarce, the "leases" may be much higher than the ~1,000 paid by the Southington Water Department. (b) A study (in mid lg78 dollars) on the cost of developing 21 an additional wel! in an already existing well field estimated the costs for a one million gallon per day well at Capital Costs ~337,000 Annual Operating Costs and maintenanc~ ~9,710 If Cost of Treatment 22 If supplies are contaminated, th~n treatment is possible. treatment plants exist and have excess capacity, a MGD may be plants do not exist, (and theymay ~iGD plant may be in If operating cost Another method new supplies are is used in the system) capital cost for 24 the neighborhood of ~1 million. Cost of Conservation of increasing mater supplies is "conservationS' indicated, conservation can extend existing of ~113,73~ (mid lg78 not a household has 1980. lawn been reduced from 200 for example, average daily use per gals. in 1977 to 140 gals. in voluntary effort, mainly in reducing 25 supplies. This was done with a · atering in the summer. ~n Tucson~ Arizona, [here are a number of different ways of effecting conservation. Un the demand side, higher prices, regulations restricting use, water saving fixtures, reuse/recycle systems, and educetion may be effective. On the supply side, meter installation, leak detection if no surface ~ater treatable for an annual 23 dollars.) If treatment and repair, and pressure reduction save ~ater. The Nam Fngland River Sasins Commission has just published a detailed report mhich ~nalyzes all these factors.Z6 The study concludes that mater conservation can reduce mater use, and that many conservation measures are cost effective, although the measures mhich save the most mater (reuse/recycle systems) are not the most ccst mffective. anO ma/ "savings" mculd no longer be possibla if an aquifer source mere to Oecome ,~nusaole. This might, however, delay the need for an addi- tional aquifer source for some years. These possiOla conservation techniques and their ccsts mould ha,~e to se considered ~ith the other alternatives alternate supplies and treatment. G£ven the cost effectiveness of some of these measures, this could Oe the least costly o~ the altarnat£ves. Care must be taken in ~rojecting cost savings figures, hcm- ever. Since fixed costs are such a large portion of per ~,a~er costs, significant conservation (lomer water demand) ~ill raise pec unit costs, and savings may not materialize. Of if conservation obviates the need ?or additional capital expendi- tures, then real savings ~ill result. The Lo,~est Cost Alternative 27 6inca many 6easures are cost effective, and many communities beooming concerned aOout fut~re st~polie~, conservation regulations be adopted b! many commwn£ties. If thLs mere so, thes~ ~t appears as though conservation may altarnativm. Homaver, the available ,~ater ficient. Acquiring an alternate source of less b~ the lomest cost saving may not b,~ suf- aqu~far mater appears expensive than treating mater. Even this alternative may 15 increase delivered water costs by perhaps 50%. This is based on current conditions. If most communities choose noS. to protect their aquifers, and if many aquifers become polluted, the cost of acq~irin§ additional supplies could be much higher. Alternately, if treating water becomes more midespread, technological changes might reduce these costs. UT~ER 6ENEFITS The other ~enefits ti~d a~ove (pp. 8-9) cannot easily be quantified. ~he ~nadequao¥ of techniques for a~ti~ating p~ices for ~on-priced o,Jtcomes are mell described in the ~IT study.28 The existence of these additional benefits means than an estimate of benefits based only on the cost of an alternative ,~ater supply · ill signiFica~tly underestimate benefits. EV~LbATI~.~N AND CONCLdS!ON Under a set of simplifying assumptions, it is possible to say that the major measurable benefit of enacting regulations to protect aq,~ifers from contamination is the cost of providing ,,sable ~ater should an aquifer become p~ll~t~d. The least expensive appropriate method appears to be acq~irinq other aquifer ~at~r. It appears reasonable to attempt to estimate this cost under current conditions. This estimate ~o~ld represent the lo,est possiOle measure of benefits becauss (1) other benefits and (2~ it cannot allow for supplies, ~hich as far as can be seen now, it does not measure changes in water will result in highe~ COSTS. Estimatin~ the present value of the future benefits presents additional problems. When wilt the additional ~ater ba needed -- in 2 years or 10 years or 20 years? Projection in this changing environment is difficult. ~hat is the appro- priate interest rate? At lO~, the present value of an ~lO0,O00 expenditure in 15 years is ~2~,000. Since the present value of future benefits ar? to be compared with current costs o, implementing regulations, the "known" benefits may net appear large. In its analysis, the ~1I~ estimating benefits for every justified by the results.2g study suggests that the costs of environmental project may not be It presents the viem that ether ,~on-gdantifieble considerations in dec~ding to regulate this vie~ for aquifers, regulation is necessary. At this time, it appears that, if may really be more important or not to regulate. 8afore accepting an examination of the probable costs of the suggested assumptions ca~ be accepted, an estimate of benefits can be made. If those mbo make the decisions on regulation wnderstand the uncertainties of forecasting, the benefit fig,~re may be a valuable input. FUOTNOTES i. Aquifers are geologic units capable of y£elding usable amounts of water. 2. Connecticut Areawide Waste Treatment management Planning Proqram. A Guide to GroundWater and Aquifer Protection. Draft, June lgTg. f,tiddletown, CT. 06457. 3. Spohn, Gustav. "Water Pollution A Growing Concern." New York Times, Connecticut Section, 1/6/80. 4. Gallagher, ~egan. "Experts Fear Shortage of Clean Drink- ing mater." Fairpress, Normalk, CT. 2/20/80. 5. These are called primary and secondary recharge a~eas, respectively. 6. This is regulated under the Flammable Liquids Cod~, ad- ministered by the Fire ~iarshall's office. Connecticut Areamide maste Treatment management Planning Program. 7. bnder current regulations, when sodium in a public mater supply is greater than 15 mg./lite~ salt may not be used for roads, drivemays or parking areas that drain into that mater supp]y, except mith permission of the Department of Health. Conn. Aream~de ~ate Treatment I~lanagement Planning Program. This does not protect future supplies. Particularly signif£cant are Committee on Governmental Affairs, United States Senate, ~enefits of Environmental~ Health and Safety Requlation, ~arch 25, lg80. (ormpared by the Center for Policy Alternatives at the ~lassachusetts Institute of Technology) and Freeman~ A. ~lyrick, The Benefits of Environmental ~mprove- ment (Baltimore: Johns Hopkins University Press, lgTg.) g. ~ncluding discussions with EPA officials in Washington, D.C. 10. [his adapts the analysis in Freeman, p~. 17-1g. 11. For d~scription of each standard, see State of Connecticbt, Department of Environmental Protection ~ater Compliance Unit. Connecticut Water Quality Standard and Criteria, Draft Revisions. 12. Recreational benefits, so important in surface water use, are not significant for aquifer mater, except insofar as a parti- cular aquifer contaminant level mould affect surface mater. 13. This must not be counted tmice if deducted from costs of controlling pollution over aquifers. i4. In progress is tha Southwestern Aquifer Assessment Program, a 3 year study which has not baen adequately fundsd. Information from ~estern Connecticut ~ater Council, not yet published. 15. there is need Per quantity of available water contamination. this information in surveying the resources and for assessment of toxic 16. Harry E. Potential of Some ~orks Association, LeGrand "System for Evaluation of Contamination ~Jasta Disposal Sites." Journal American Water vol. 56, (1964) p. 972. 17. P. t8. P. 960. lg. Further mork is Oeing done O~ L. Frankel, Professor of Geology, Whir. of Conn.. 20. The companies which caused the pollution are being sued~ It is not yet clear if they will be fined and who will get the money. Data frcm Dan Christy, Superintendent, Soothington !Vater Department, telephone conversations g/iS/80, 9/22/80. 21. New Haven ~ater Company. Cost Comparison of 1 MCD Packaqe Treatment Plant vs. 1,1GD ~ell, January 1979. 22. Assuming no toxic mastes. 23. New Haven Water Company. Cost Comparison. 24. Loc. cit. 25. the ,'~ew York rimes, 5/8/80. vol. I. 26. New England River ~asins Co~mission. 8afore the Dry: Literature Swrvey and Analysis of ~ater Conservation, 27. P. 96. 28. Pp. 16-19. 29. P. 43.