Code of Colorado Regulations
1000 - Department of Public Health and Environment
1002 - Water Quality Control Commission (1002 Series)
5 CCR 1002-35 - REGULATION NO. 35 - CLASSIFICATIONS AND NUMERIC STANDARDS FOR GUNNISON AND LOWER DOLORES RIVER BASINS
Section 5 CCR 1002-35.16 - STATEMENT OF BASIS, SPECIFIC STATUTORY AUTHORITY AND PURPOSE; May, 1990 HEARING ON SEVERAL SEGMENTS

(1) detection limits for some data were too high to determine whether ambient quality was better than "table values;"

(2) for some segments there was not adequate data for some or all of the twelve parameters referenced in section 3.1.8(2)(b)(i)(C);

(3) for some segments the sample location(s) of available data were too limited to generalize the results to the whole segment.

The Commission explicitly considered establishing minimum data requirements when it adopted the current antidegradation regulations, and consciously rejected that option. Rather, the Commission recognized that it would be necessary to reply on best professional judgment to determine what constitutes representative date in a specific situation. These issues are not new, or unique to high quality designations. The Commission has for years been required to make water quality classifications and standards decisions in the absence of perfect information. Requiring substantial, recently acquired data for all parameters from multiple locations in each segment before establishing high quality designations would assure that very few waters in Colorado would receive this protection for many years to come. As a policy matter, the Commission has determined that high quality designations may appropriately be established based on a lower threshold of available data than that suggested by several parties to this proceeding.

The Commission also notes that having adequate information upon which to base a high quality designation is not dependent solely on the availability of specific data for a particular segment. Relevant information my include data from downstream segments, comparison of available data with that for similar streams, and information regarding the presence or absence of activities likely to adversely impact the quality of the segment in question.

Where there is a substantial basis for considering a high quality 2 designation, in the face of some residual uncertainty the Commission has chosen or err in the direction of providing the protection. This policy decision is strongly influenced by the ease with which designations can be changed if better data is developed in the future. Unlike classifications, downgrading restrictions do not apply to water quality designations. If new site-specific data is developed that demonstrates that a particular high quality designation is improper, it can and should be removed the Commission.

With respect to detection limits, the Commission has chosen to continue the same policy that it has followed for over ten years-i.e. to treat data reported as below detection limits as being equivalent to zero, while other methodologies have been proposed and may be defensible, the Commission that this approach is reasonable and appropriate. Requiring routine analysis to below table value standard levels for all constituents would substantially increase monitoring costs for the state and the public. Moreover, the Commission believes that the "zero" assumption is fair, so long as it is applied consistently throughout the water quality regulatory system.

Use of zeros in the water quality designation of standard-setting process may marginally err in the direction of increased protection. However, when zeros are used in applying standards to specific dischargers, those dischargers benefit by the assumption that there is more assimilative capacity available in the stream (allowing higher levels of pollutants to be discharged) since the existing pollution is considered to be zero rather than some level between zero and the detection limit.

The second recurring issue addressed for multiple segments in this hearing was whether to establish a recreation class 1 classification wherever a high quality 2 designation is established. The Division proposed this classification change for applicable segments, since the high quality 2 designation indicates that such segments have adequate water quality to support the recreation class 1 use. However, the Commission generally has declined to change the recreation classification from class 2 to class 1 in such circumstances, unless there was also evidence submitted that class 1 use were present or likely for the waters in question. Unless the use is present or likely, application of use-protection-based water quality standards does not appear appropriate. At the same time, the Commission notes that this approach does not diminish application of antidegradation protection requirements for high quality waters. Where the existing quality is adequate, a high quality 2 designation has been established, requiring antidegradation requirements to be met before any degradation is allowed, even though the recreation classification is class 2.

A related issue is the determination of which uses warrant the class 1 recreation classification. The recreation classification definition in section 3.1.13 of the Basic Standards and Methodologies for Surface Water refers to "activities when the ingestion of small quantities of water is likely to occur," and states that "such waters include but are not limited to those used for swimming." In the past the Commission often has applied the class 1 classification only when swimming occurs, and not where other recreational uses that may result in ingestion of small quantities of water occur. The Commission now believes it is appropriate for the class 1 classification also to be applied for uses such as rafting, kayaking, and water skiing.

The appropriateness of recreation class 1 versus class 2 classifications was debated for several segments in the Gunnison Basin. The Commission has received information regarding actual recreational uses. It has also received substantial input regarding the property (of lack thereof) of broadening the application of the class 1 recreation classification, based upon an evolving interpretation of the Basic Standards language. After lengthy discussion, the Commission has decided that it is appropriate as a matter of policy to begin in this basin to apply the recreation class 1 classification for all uses that involve a significant likelihood of ingesting water, including but not necessarily limited to rafting, kayaking, and water skiing. The Commission received substantial testimony that kayaking often results in water ingestion. In addition, the testimony presented, as well as the personal experience of individual Commissioners, indicates that rafting-white water or othenwise-also presents a significant potential for water ingestion.

Section 3.1.6 (1)(d) of the Basic Standards and Methodologies for Surface Water requires the Commission to establish classifications to protect all actual uses. Therefore, for waterbodies where rafting and kayaking is an actual use, the recreation class 1 use classification should be applies, since ingestion of water is likely to occur. The Commission sees no reason to distinguish between ingestion that may result from swimming and ingestion that may result from rafting or kayaking. In fact there was some testimony indicating that ingestion is more likely to result from the latter activities.

The Commission wishes to emphasize that the action that it is now taking is consistent with the existing definition of class 1 recreation uses. Some of the comments submitted stated or suggested that the action now being taken by the Commission would constitute a "definitional change" that should be addressed only in a review of the Basic Standards and Methodologies for Surface Water. No change in the regulatory definitions of the classifications is being considered or adopted at this time. Rather, the Commission is applying what it believes to be the proper interpretation of the existing definition.

The Commission believes tinat as a matter of policy it is not necessary or appropriate to wait until the July, 1991 rulemaking hearing regarding the Basic Standards and Methodologies for Surface Water to implement its current interpretation of the class 1 recreation classification. Over the last decade, there have been many instances when arguments and facts presented in basin-specific rulemaking hearings have resulted in an evolving interpretation of the provisions of the Basic Standards and Methodologies for Surface Water. This Commission is not bound by interpretations made by its predecessors in other basin-specific hearings. To the degree that the class 1 recreation classification in the past has not been applied for some existing activities that involve a likelihood of ingesting water, the Commission now believes that such decision were in error.

This action does not improperly exclude input from entities interested in other river basins. First, the Commission specifically reopened this hearing and received input from entities not specifically concerned with the Gunnison basin. Moreover, the Commission can further modify its policy if in other basin-specific reviews, or in the upcoming review of the Basic Standards and Methodologies, parties that did not participate in this proceeding bring forth new considerations that the Commission believes warrant a modification in the approach to recreation classifications that is now being adopted. The Commission also does not believe that there was any problem with the notice provided for the specific segments at issue in the hearing. Each of the segments for which the recreation classification is being changed from class 2 to class 1 based on rafting or kayaking uses were proposed to be changed to class 1 in the original hearing notice. Although the basis for this proposal evolved during the hearing, any parties potentially concerned with a recreation class 1 classification were on notice that this change would be considered in this hearing.

In applying the interpretation of the existing recreation class 1 definition that has been described, the Commission is also influenced by the fact that the importance of recreational uses of surface waters in Colorado has increased over the last decade. Testimony indicated that uses such as rafting and kayaking have expanded substantially, and it is therefore even more important that adequate water quality protection now be provided.

Some of the testimony submitted addressed the appropriateness of the current fecal coliform standards that are applied in association with recreation classifications. The Commission believes that the appropriateness of the existing standards can and should be addressed, when and if there is new evidence available indicating that the current standards are not appropriate. However, changes in such standards were not at issue in this hearing. The Commission believes that questions regarding the appropriate numerical standards should not interfere with its obligation to establish appropriate classifications to protect existing uses. If members of the public have information indicating that a different indicator parameter should be used, or that different fecal conforms levels are appropriate for the respective recreation classifications, that issue can and should be considered in the upcoming review of the Basic Standards and Methodologies for Surface Water.

Comment was also submitted to the Commission expressing concern regarding the potential effect of downgrading restrictions, should the Commission now adopt class 1 recreation classifications for certain waters and later change its views regarding the appropriate approach to recreation classifications. The Commission does not believe that this presents a substantial problem. Downgrading is appropriate only when a use is not in place. So long as the class 1 recreation classification is defined as including activities that involve ingestion, applying that classification to waters where uses involving ingestion are present should not present a downgrading issue in the future. If the Commission at some later date should completely revise its approach to, and definition of, recreation classifications, application of the new system would involve a set of "de novo" determinations, and not questions regarding upgrading or downgrading.

The Commission recognizes tine approacin now being adopted may result in increased economic impacts for some disclnargers, to meet tine class 1 classifications. The evidence submitted indicated that in many instances this will not be the case, because state-wide effluent limitations for fecal conforms and chlorine standards to protect aquatic life will often drive the level of disinfection and dechlorination that are required. However, in some circumstances it may be possible for the Division to consider an exOanded use of seasonal effluent limitations that take low flow or high flow circumstances into account. However, irrespective of these considerations, a potential increase in treatment requirements for dischargers cannot eliminate the Commission's obligation to classify state waters to protect actual uses.

Finally, concern was expressed that the approach now taken by the Commission will result in inconsistency regarding recreation classifications for different waters throughout the state. Anytime a policy interpretation changes or evolves in any significant way, the first time the change is applied to specific state waters there will be some inconsistency among individual water bodies, since site-specific classifications and standards are addressed on a basin-by-basin basis. However, it is the Commission's intention to apply its policy interpretations consistently as individual basins are addressed.

The third recurring issue was the proposal by several parties that the Commission substantially resegment several existing stream segments, creating additional segments. The Commission generally has declined to resegment where there was not information submitted justifying different water quality designations, classifications or standards within separate portions of existing segments. Where there is not such a basis for increasing the number of segments, the Commission believes that resegmentation would unnecessarily add additional complexity to the current system.

(1) the quality is not suitable for a water supply classification or 85'^ percentile values of one or two parameters exceed the criteria for class 1 aquatic life; or

(2) the Commission has determined that there is currently inadequate information available upon which to base a high quality 2 designation.

The segments that fall in the latter category are Upper Gunnison segments 22 and 33; North Fork segments 7 and 9, and Lower Gunnison segments 3 and 5. For example, for Upper Gunnison segment 33 there is some data showing table value exceedances for two parameters. Although the Division questioned the reliability of this data, no alternative data is available at this time. However, the Commission also notes that table value standards, rather than ambient quality standards, have been established for this segment since the available data do not create a reliable basis for specific ambient quality standards at this time. For North Fork segment 9, not only is there limited data available on this segment, but available information regarding other waters in this subbasin does not support the conclusion that these are high quality waters,. The Commission also rejected proposals to change the aquatic life classification of North Fork segment 7 to class 2 with a use-protected designation, and to resegment Lower Gunnison segment 3, because these proposals were not supported by the evidence.

For North Fork segment 5, the Commission has rejected a proposal to change the recreation classification from class 1 to class 2. This hearing was not noticed pursuant to section 25-8-207, C.R.S., which provides authority to revise classifications based on material assumptions that were in error or no longer apply. If one of the parties, or any other member of the public, believes that the current classification is in error and that it may have an adverse impact on their activities, such a hearing may be requested in the future to consider this issue.

The Division proposed that the recreation classification for North Fork segment 3 be changed from class 2 to class 1. The Commission rejected this proposal due to inadequate information that such uses are in place or likely.

Table value standards are adopted for all parameters for all segments noted in Paragraph F except as follows:

In addition, three-year temporary modifications have been adopted for the following segments and parameters: