5 Colo. Code Regs. § 1002-61.26
The provisions of 25-8-202(l)(d) and 25-8-501 to 25-8-504, C.R.S. provide the specific statutory authority for adoption of these regulatory provisions. The Commission also adopted, in accordance with 24-4-203(4), C.R.S. the following Statement of Basis and Purpose.
Several parties to the hearing contend this regulation is essentially a "water quality standard" pursuant to Section 25-8-204, and/or a "control regulation" pursuant to Section 25-8-205, and that the requirements for regulations promulgated under these sections have not been met. The biomonitoring regulation, however, is neither of these. It is a permit condition, which the Commission is authorized to regulate pursuant to Section 25-8-20(1)(d) and (2); thus, the requirements of Section 25-8-204 and 205 do not apply to the regulation.
BASIS AND PURPOSE:
Overview
Protection of aquatic life uses of surface waters in Colorado warrants biomonitoring requirements in discharge permits. Chemical testing alone cannot predict the biological effects of effluent constituents. Toxicity can arise from synergistic interactions among multiple effluent constituents, none of which alone would be toxic, and such effects cannot be predicted. Whole effluent toxicity (WET) is completely different from conventional pollutants in terms of its nature, its sources, and its treatability. The addition of WET testing to the Colorado program will provide greater assurance that continuous sources of effluent toxicity are being addressed. The purpose of the new biomonitoring provisions in Section 6.9.7 is to implement an effective program to control toxic effluent discharges in the State of Colorado, to identify and eliminate, to the extent possible, recurrent WET in domestic and industrial discharges, and to provide direction to the Division on the implementation of the "free from toxics" section of the Basic Standards and Methodologies, 5 CCR 1002-8, Section 3.1.11(1) which states in part:
"Substances attributable to human-induced discharges... shall not be introduced into waters of the State... in amounts, concentrations or combinations which are harmful to the beneficial use or toxic to humans, animals, plants or aquatic life."
This new section provides guidance on the use of acute biomonitoring as a detective tool for the detection and control of WET and the characterization of toxicants. As used in the 1988 biomonitoring provisions, the term "toxicity" refers only to toxic effects on aquatic organisms such as fish and macroinvertebrates, and carries no implication whatsoever relative to human health effects. A separate policy statement prepared by the Division addresses implementation of the "free from toxics" provision as it applies to human health.
Chemical analysis of effluent provides only a partial evaluation of the potential toxicity of a discharge to aquatic life. Monitoring for all potentially toxic compounds on a continuous basis for each discharger would be extremely costly. Even if cost-effective, chemical analyses are unable to determine the biological significance of the presence of concentration of specific chemicals in an effluent, and cannot evaluate the synergistic or antagonistic effect of compounds in causing effluent toxicity. There are compounds for which an accurate (or reproducible) method of chemical analysis has not yet been developed, as well as compounds which are just beginning to be evaluated for toxic effects. Biomonitoring provides a means of evaluating the toxicity of a discharge which could not otherwise currently be accomplished.
Similarly, biomonitoring alone provides insufficient information for the development of control programs to eliminate effluent toxicity. Biomonitoring detects WET but cannot identify the specific compounds causing toxicity. Both biomonitoring and chemical testing are necessary components of effective toxicity control programs. Thus, the successful implementation of toxicity control programs will require a combination of biomonitoring and chemical testing, and the costs of toxics control will reflect the costs of biomonitoring, chemical testing, and pretreatment program administration.
Apparent differences between direct discharging industries and POTW's center on the fact that POTW's may receive highly variable influents, some of which they have little or no control over, while the wastewater treatment operations of industrial facilities receive wastes of relatively constant quality over which the industry has complete control. While POTW's do receive highly variable influent this may also be true in some cases for industries. Although treatment of toxicants is an option, treatment may not be a practical option for POTW's except where the toxicants are nonionized ammonia or residual chlorine. POTW's generally may have to rely on the identification of toxicants and the elimination of toxicant sources to control WET, while industries may be able to rely on treatment. The major difference between industries and POTW's regarding control of WET may be that industries will require less time to identify the cause(s) of toxicity. The time requirements for implementation of control options, especially where construction of treatment facilities is concerned, are unlikely to vary greatly between industries and POTW's.
Biomonitoring shall be implemented in the State of Colorado in a manner consistent with the stream classifications and standard setting process. This means that stream dilution as well as stream classifications will be considered in defining biomonitoring test procedures. If a situation arises where the benefits of controlling WET are not commensurate with the costs, the Commission may enact a site-specific modification to the standard.
Applicability
In establishing the regulation, a distinct effort was made to allow consideration of site specific conditions. Examples of this are found in the industrial and domestic exemptions and in the modification of test protocol. As future information is gained additional flexibility may be adopted as a result of recommendations of the biomonitoring task force.
Industrial categories exempted from the biomonitoring provisions are those which have been shown not to be significant contributors of pollution and in the case of exploratory mines, where historic drainage exists, to be consistent with the existing mine policy of the Division.
New industrial permittees are required to meet a stricter standard of performance for controlling WET than renewal permit applicants, in that new industrial dischargers for which it is possible to simulate the effluent quality must show that the effluent will pass the appropriate biomonitoring test(s) prior to receiving a permit. A new facility which is subject to chronic monitoring is encouraged to have the pollution control equipment necessary to pass the chronic toxicity test in place and ready to operate at the time of discharge in order to avoid as much as possible the introduction of toxic pollutants into the environment.
New domestic permit applicants, due to the potentially complex nature of the influent as well as the inherent inability of the domestic discharger to control or simulate all potential discharges into the sewer system, are not bound by the provisions for new industrial applicants.
Domestic dischargers are provided the opportunity to seek a waiver from the biomonitoring provisions due to the costs associated with biomonitoring but only if toxicity is shown not to be a potential problem.
Biomonitoring will be required of domestic dischargers with facility design capacity greater than 5 MGD. Domestic dischargers with facility design capacities less than or equal to 5 MGD will be exempt from biomonitoring requirements unless the Division finds that biomonitoring requirements are warranted on a site specific basis. The 5 MGD cutoff was selected because it is logical to assume that toxicity problems are more likely to occur in discharges from larger facilities, and the selection of the 5 MGD cutoff softened the economic impact of biomonitoring on small POTW's. A distinction has been made between domestic permittees under five MGD which treat only domestic wastewater and those which do not. This distinction is warranted in view of the higher risk of toxicity which may be associated with discharges that contain commercial and/or industrial contributions. The Division retains the latitude to require biomonitoring of smaller dischargers for cause.
Although national concerns over effluent toxicity have focused on direct and indirect industrial discharges, there is reason to suspect that some toxicants in POTW effluents may originate from household wastes. Detergents, disinfectants, emulsifiers, cleaning agents, solvents, petroleum products, contraceptive agents, and pesticides can all enter domestic sewers from households. Copper, lead, and zinc may enter sewers from household plumbing corrosion. It is important to assess the significance of potential toxicants from domestic sources in order to structure an effective toxicity control program. Additionally, where domestic-only facilities which accept septage exist close to industrialized areas where a pretreatment program is in effect, the opportunity exists for industries to avoid pretreatment by having toxic wastes hauled by septage haulers to domestic-only POTW's which do not perform biomonitoring.
Basis for Enforcement
WET cannot be predicted accurately because specific chemical testing cannot predict either the biological significance of effluent constituents or synergistic interactions among effluent constituents. The requirements of Section 6.9.7 are principally intended to address ongoing WET resulting from normal operations. Section 6.9.7 generally is not intended to address one-time, non-repeated events such as illegal dumps. These events are addressed elsewhere in the permit regulations.
Because WET cannot be predicted accurately and thus is not under the permittee's close control, the traditional approach to enforcement in which an exceedance of a permit limit constitutes an enforceable permit violation is not appropriate. Section 6.9.7 specifically replaces the traditional numeric permit limit with a mandatory sequence of tiered responses which lead to a systematic investigation of toxicant identification and sources, and of treatment options, in a timely manner. The regulation focuses resources on the problem of WET elimination, rather than emphasizing penalties.
Enforcement of toxicity limits is keyed to the diligence with which dischargers who identify recurrent WET pursue the elimination of WET. This mode of enforcement is justified because in the case of domestic facilities treatment plants have not been designed to treat toxics. Dischargers must be given the opportunity to investigate and eliminate WET before findings of permit condition violations are appropriate. Enforcement based on the results of individual biomonitoring tests was rejected because it is only practical to control recurrent WET, because of the Commission's desire to afford dischargers an opportunity to investigate the causes of toxicity, and because WET may appear through no fault of the discharger, as a result of activities beyond his control. Further, some uncertainty yet exists relative to the accuracy of a single test and the impact of a single discharge upon the uses of the receiving stream. Biomonitoring for information purposes only, with no enforcement provisions, was rejected so that the Division would have authority to require diligent efforts to investigate and eliminate WET. In addition, if toxicity were found, but no mechanism existed to investigate and attempt to correct the same, both the Division and dischargers would potentially be subject to citizen suits.
Diligence is judged using three criteria: Timeliness of response, use of appropriate analytic methodologies, and use of adequate quality control procedures to assure the integrity of analytic results. Timing of response requirements throughout the toxicity incident response are specified in the body of Section 6.9.7 . Guidance for determining the appropriateness of analytic methodologies and quality control measures is provided in Guidance for Conducting Toxicity Reduction Evaluations in Colorado.
Section 6.9.7 provides for penalties of up to $10,000 per day for periods during which a permittee displays a lack of diligence in investigating or controlling WET.
There is Division concern that the enforcement approach for biomonitoring based on diligence may not provide adequate incentive for an entity to investigate the toxicity or impact of new effluent sources prior to initiating discharge. This concern is more directly addressed through current permit provisions which require Division notification of any facility change such as additions or alterations which may change effluent quality or quantity. If a permittee detects WET, satisfies all provisions of Section 6.9.7 for investigation and elimination of WET, and determines that the cause of WET is a new source or activity that was inadequately evaluated prior to commencement of the discharge, the Division may proceed with enforcement based on violation of appropriate permit provisions. Examples of violations cited in such situations may be failure to notify the Division of a change in the character of the effluent (quality or quantity) or the discharge of an unauthorized pollutant.
Intake Credits
Some stream segments are polluted from natural sources, nonpoint sources, or abandoned mine activities to the degree that they could exhibit toxicity through biomonitoring. It is appropriate for entities to be responsible for remediation of adverse water quality impacts from the addition of pollutants to surface waters, but generally it is not appropriate to require entities to remediate poor water quality conditions found in the intake water. Thus, a credit is provided in Section 6.9.7 . Where the water is treated for potable or industrial purposes, however, the credit is based upon toxicity levels present following the treatment. Toxicity in the intake water should not be considered part of a pattern of toxicity for the discharge. A concern was expressed over the discharge of potentially toxic intake waters to different segments of a better quality. Thus, to qualify for the credit, the discharge must be to the same stream segment from which it was withdrawn or downstream segments of equal or lesser standards.
Test Methods
The test methods identified in the regulations are those which the EPA has published. These methods have been included to insure consistency among permittees as well as to insure utilization of an EPA approved methodology which is a requirement of Colorado discharge permits. It should be noted that EPA is updating the chronic test methods and should be issuing the revision within a year.
The Division has drafted a guidance document entitled Guidelines for Conducting Whole Effluent Toxicity Tests, which will serve to eliminate confusion on the part of Colorado permittees concerning biomonitoring test protocols as EPA continues to develop new biomonitoring methodologies. The discharge permit represents a binding legal contract, including those portions, such as analytical methodologies, incorporated by reference. The Division Guidance will establish the biomonitoring test procedures which Colorado dischargers must follow. Revision of this guidance by the Division will trigger a distribution of the new guidance document to permittees of record.
Acute Toxicity Limit
The acute toxicity limit is established in two parts. The first part acknowledges the stream standard process in the State of Colorado through the instream waste concentration (IWC). This part of the limit is a dilution of the discharge, expressed as a percentage, at and below which the detection of a pattern of toxicity triggers the requirement to undertake a toxicity incident response aimed at eliminating WET. This part of the acute toxicity limit is site-specific, dependent via the IWC upon the low flow of the receiving water and the rate of discharge. However, in order to insure that the effluent as a whole does not have a significant toxicity problem, the second part of the limit was established to allow no mortality greater than 50% in any dilution of the effluent. The 50% mortality portion of the limit is consistent with the current mixing zone provision contained in the basic standards, 5 CCR 1002-8, Section 3.1.9(3).
Consistent with the basic standards, the acute toxicity limit applies to all state water regardless of classification. In order to apply the limit to an unclassified segment, or in the case of a discharge to a stream segment not classified for the protection of an aquatic life use, the limit is modified via the IWC by using the low flow statistic of the next downstream segment classified for the protection of aquatic life uses, rather than the low flow statistic of the receiving segment. In order to relieve economic burdens on small dischargers, the effluent volume used for calculating the IWC Is the design capacity of the facility stipulated in the current permit. The 50% mortality portion of the limit, however, also continues to apply.
Numeric standards for specific compounds always supersede more general standards such as WET. Where WET can be attributed to specific compounds, stream standards and permit limits for such compounds will be set at levels adequate to protect receiving stream uses up to a numeric limit equal to the 50% mortality portion of the limit. These specific standards and limits rather than the acute toxicity limit will be the primary means of control. Where WET is detected and the benefits of controlling WET are not commensurate with the costs, the Commission may establish a site-specific modification to stream standards.
Toxicity Reduction Evaluation
It is the intent of this regulation to require dischargers to undertake biomonitoring of their effluents to provide an indication of whether the effluents contain toxic materials. If biomonitoring tests show that toxic materials in toxic amounts may exist in the effluent, then these regulations require further action by dischargers to find the cause and to eliminate to the extent possible, any unacceptable level of in-stream toxicity. The Toxicity Reduction Evaluation (TRE) has been included as a mandatory provision of the biomonitoring regulation and has been structured to allow permittees flexibility in determining the cause(s) of toxicity where a recurring pattern of acute toxicity is demonstrated in an effluent, or where the preliminary toxicity investigation is unsuccessful in identifying the cause(s) of toxicity. Flexibility in determining the cause(s) of toxicity is afforded to permittees both by the preliminary toxicity evaluation, and by the fact that the Phase II TRE is developed on a case-by-case basis. The current Methods for Toxicity Reduction Evaluations, Phase I. Toxicity Characterization Procedures (Draft June 24, 1988) published by EPA addresses only the Phase I TRE procedures and is only a draft document at this time. However, in order to insure consistency in methodology between individual permittees which conduct a TRE, the most current EPA guidance has been identified as the appropriate guidance methodology.
However, where specialized requirements and time frames are encountered such as in the Phase II TRE Plan, and the control program, permit reopening is necessary in order to have an enforceable document, provide the permittee legal recourse where there is disagreement and provide the public an opportunity for input. Thus, there is some potential for delay in the process.
While the Commission is aware that the Clean Water Act toxics requirements may be limited in certain instances to the 307(a) pollutants, states have the authority to adopt standards more stringent than federal requirements. Recognizing that chemical testing is not adequate to predict the biological effects of effluents and recognizing that toxicity may result from synergism between constituents which by themselves are not toxic, it was determined that biomonitoring requirements are justified in the interest of protecting aquatic life uses.
Chronic Toxicity Monitoring
Chronic biomonitoring is not required of as broad a group of dischargers as acute biomonitoring because of questions about the sensitivity and reliability of the test methodology, and the fact that toxicity characterization (Phase ITRE) methods have not yet been developed for chronic toxicity. The need for chronic toxicity monitoring will be determined based upon the type of discharge, the classification of the receiving stream and appropriate low flow to effluent ratios. The Division will have the discretion to require chronic testing for dischargers to stream segments without aquatic life numbers where appropriate. An example of a situation in which such requirements would be appropriate is where a determination is made that an aquatic life segment will be adversely impacted by a discharge to an upstream non-aquatic life segment.
Pretreatment
It is the intention of the Commission that, upon renewal or reopening of municipal permits with biomonitoring requirements in conjunction with pretreatment programs, the Division will delete those requirements and incorporate requirements consistent with Section 6.9.7.
Incorporation Into Permits
The biomonitoring requirements of Section 6.9.7 will be applied to all new and renewal permits as well as permits reopened consistent with the State Discharge Permit System regulation, 5 CCR 1002-2, Section 6.9.3(8).
Fiscal Impact
The costs incurred by the permittees to satisfy the new application test requirements and the compliance test requirements will vary depending on whether the permittee must conduct both acute and chronic tests and whether the permittee conducts the test at their own laboratory or contracts with an outside laboratory.
The Environmental Protection Agency has estimated the costs for a contract laboratory to be: $400 for the acute Ceriodaphnia test, $550 for the acute fathead minnow test; $1000 for the chronic Ceriodaphnia test and $1100 for the chronic fathead minnow test. However, EPA has also recognized that as more laboratories begin to conduct biomonitoring tests the market will become more competitive and the prices should lower.
Based on EPA cost estimates, the following costs have been projected to illustrate the direct costs that may be incurred by a discharger as a result of the adoption of the biomonitoring regulation.
A wide range of cost estimates for testing were submitted, ranging up to twice the estimated costs present here. In addition, it is acknowledged that the estimated costs could represent a significant financial burden for small dischargers such as mining operations. However, it has been determined that the benefits at this time outweigh such burdens. This issue may be re-explored by the Task Force.
Comparatively the cost that the permittee would incur if as complete chemical analyses as possible were required, instead of biomonitoring, is estimated to be: $250 for metals, $165 for radium, $1000 for priority pollutants and $1000 for the hazardous substance list. The actual cost will depend upon the laboratory analyzing the wastewater and as stated in the overview there are compounds for which analytical methods have not yet been accepted or developed.
The largest cost for biomonitoring will be to facilities which must conduct both acute and chronic tests and these costs will be the largest in the first year of sampling. Any facility which has toxicity present in the discharge will incur more costs. The cost for conducting a TRE will increase if the Phase I TRE cannot identify the toxicity problem and a Phase II TRE must be conducted. Costs for eliminating the cause of toxicity will vary depending on whether the pollutant can easily be removed from the discharge through either removal from a POTW collection system or through treatment. If pollutants are removed from POTW collection systems there may be additional cost involved with alternate disposal. Some treatment technologies could add a substantial cost to the facility for installation and operation and maintenance.
Biomonitoring Task Force
During testimony for the biomonitoring regulations, many concerns were raised relative to technical and implementation issues. The concerns have included benefits to be derived from the program, technical issues with testing and follow-up investigations on toxicity incidents as well as costs associated with the various stages. There was also concern as to the adequacy of the adopted regulation and future modification of the regulation. In order to address these concerns and produce a more refined program for the future a biomonitoring task force will be established.
A member of the Water Quality Control Commission will chair the task force which will consist of a maximum of 12 additional people. To the extent feasible, representation will be based upon agencies and interests such as the following: large and small municipalities, large and small industries, mining, one or more environmental groups, EPA, the Water Quality Control Division, the general public, and a contract laboratory.
During the first three years the general charge of the task force will be to:
The Division should to the extent feasible provide to the task force all available, non-confidential analytical data, cost data, and technical issues plus pertinent information on biomonitoring received from permittees. It is the Commission's intent to establish the task force for advisory purposes only. Responsibility for implementation of the biomonitoring program resides with the Division.
PARTIES TO THE PROCEEDINGS
5 CCR 1002-61.26