Code of Colorado Regulations
1000 - Department of Public Health and Environment
1002 - Water Quality Control Commission (1002 Series)
5 CCR 1002-33 - REGULATION NO. 33 - CLASSIFICATIONS AND NUMERIC STANDARDS FOR UPPER COLORADO RIVER BASIN AND NORTH PLATTE RIVER (PLANNING REGION 12)
Section 5 CCR 1002-33.10 - STATEMENT OF BASIS AND PURPOSE

(a) These regulations are not adopted as control regulations. Stream classifications and water quality standards are specifically distinguished from control regulations in the Water Quality Control Act and it is the view of the Commission that they need not be adopted as control regulations pursuant to the statutory scheme. The Commission has specifically endorsed the view of the attorney general on this issue, which is a part of the record of these hearings.

(b) The Commission was requested in the public hearings to rule on the applicability of these and other regulations to the operation of water diversion facilities, dams, transport systems, and the consequent withdrawal, impoundment, non-release and release of water for the exercise of water rights. The Commission has determined that any such broad ruling is inappropriate in the context of the present regulations. While the request raises significant issues that must be addressed, the Commission is aware of the current practices of the Division. In addition, these questions are currently the subject of litigation and involve complex legal issues. It is anticipated that the Commission will address these issues in the proper context and upon a review of relevant information. The request does not raise specific questions as to proposed classifications and standards; however, the Commission has taken into account the fact that these issues are unresolved in assigning classifications and standards as is more fully discussed below.

(a) For purposes of assigning classifications and water quality standards, the streams and water bodies of Region 12 are identified according to river basin and specific water segments.

(b) Within each river basin, specific water segments are defined to which use classification and numeric water quality standards are assigned. These segments may constitute a specified lake or reservoir, or a generally defined grouping of waters within the basin (i.e., a specific mainstem segment and all tributaries flowing into that mainstem segment).

(c) Segments are generally delineated according to the points at which the use or water quality characteristics of a watercourse are determined to change significantly enough to require a change in use classification and/or water quality standards. In many cases, such transition points can be specifically identified from available water quality data. In other cases, however, the delineation of segments is based upon best judgments of where instream changes in uses of water quality occur, based upon upstream and downstream data.

(a) The use classifications have been assigned in accordance with the provisions of Section 3.1.6 and 3.1.13 of the basic regulations. Each classification is based upon actual current uses or existing water quality. In the latter case, even though the use may not be in place, the classification is attached if existing water quality would allow that use.

(b) In all cases, the requirement of the basic regulations, Section 3.1.6 8, that an upstream use cannot threaten or degrade a downstream use, has been followed. Accordingly, upstream segments of a stream are generally the same as or higher in classification than downstream segments. In a few cases, tributaries are classified at lower classifications than mainstems, where the flow from the tributaries does not threaten the quality of mainstem waters and where the evidence indicates that lower classifications for the tributaries is appropriate.

(c) The Commission has determined that it has the authority to assign classifications "High Quality Waters - Class 1" and "High Quality Waters - Class 2" where the evidence indicates that the requirements of Section 3.1.13 has been determined on a case-by-case basis.

(d) The classification "High Quality Waters - Class 1" has been assigned where the following factors are present:

(e) Not all segments located within wilderness areas have been classified "High Quality Waters - Class 1". In addition, rivers designated under the Wild and Scenic Rivers Act and streams providing unique habitats for threatened species of fish have not been classified "High Quality - Class 1". These segments have been classified "High Quality -Class 2", for the following reasons:

(f) The "High Quality Class 2" classification was proposed for many segments located on National Forest Service lands and in other instances. These proposals have been rejected, and the segments classified for specific uses, for the following reasons:

(g) The Commission feels that the classifications are socially, economically, and technically justifiable.

(h) Qualifiers -- "Goal"

The "goal" qualifier (Section 3.1.13 , basic regulations) has been used in specific cases where waters are presently not fully suitable for the classified use, but are intended to become so. In all such cases, water quality standards have been assigned to protect the classified uses and temporary modifications have been granted for specific parameters.

(i) Qualifiers -- "Interrupted Flow"

The Commission has considered appending the "interrupted flow" qualifier to numerous stream segments in accordance with Section 3.1.13 8 of the basic regulations; however, numerous questions have arisen as to its meaning and applicability. The intention of the provision is to allow the Commission to classify certain stream segments according to their water quality, despite the existence of flow problems. It has not been included in order to eliminate confusion as to its applicability to diminished, as opposed to interrupted, flows. It has also been eliminated in order to avoid any misimpression regarding benefits to dischargers. This qualifier is essentially a statement of the obvious, particularly in view of the provision regarding low flow exceptions (Section 3.1.9(1), basic regulations).

In addition, where flow characteristics permanently impair the suitability of the stream segment to provide a habitat for a wide variety of aquatic life, the "Class 2 - Cold Water Aquatic Life" classification has been assigned.

(j) Recreation - Class 1 and Class 2

In addition to the significant distinction between "Recreation - Class 1 and Recreation -Class 2" as defined in Section 3.1.13 of the basic regulations, the difference between the two classifications in terms of water quality standards is the fecal coliform parameter. "Recreation - Class 1" generally results in a standard of 200 fecal coliforms per 100 ml; "Recreation - Class 2" generally results in a standard of 2000 fecal coliforms per 100 ml.

The Commission has heard considerable testimony on the issue of applying these classifications and has deliberated on it at length. The Commission has decided to classify as "Recreation - Class 2" those stream segments where primary contact recreation does not exist and cannot be reasonably expected to exist in the future, and where municipal discharges are present which may be unnecessarily affected by the "Recreation - Class 1" classification, to their detriment and that of the aquatic life in the stream segment. The Commission has decided to classify as "Recreation - Class 1" those stream segments where primary contact recreation exists, or where the fecal coliform standard of 200 per 100 ml. is being met and no point source discharges exist, despite the absence of the primary contact use. The reasons for these decisions are as follows:

(a) The water quality standards for classified stream segments are defined as numeric values for specific water quality parameters. These numeric standards are assigned as the limits for chemical constituents and other parameters necessary to protect adequately the classified uses in all stream segments.

(b) Not all of the parameters listed in the "Tables" appended to the basic regulations are assigned as water quality standards for Region 12. This complies with Section 3.1.78 of the basic regulations. Numeric standards, in some cases, have not been assigned for parameters on which there is no data and no knowledge of the occurrence in Region 12.

(c) A numeric standard for the temperature parameter has been assigned as a basic standard applicable to all waters of the region in the regulations. The standard of a 3 degree temperature increase above ambient water temperature as defined is generally valid based on the data regarding what is necessary to support an "Aquatic Life - Class 1" fishery. The standard takes into account daily and seasonal fluctuations; however, it is also recognized that the 3 degree limitation as defined is only appropriate as a guideline and cannot be rigidly applied if the intention is to protect aquatic life. In winter, for example, warm water releases from reservoirs (which might not be subject to the standard in any case) may be beneficial to aquatic life. It is the intention of the commission in assigning the standard to prevent radical temperature changes in short periods of time, which are detrimental to aquatic life.

(d) Numeric standards for organic substances have been assigned as basic standards applicable to all waters of the region in the same manner as the basic standards in Section 3.3.5 of the basic regulations. These standards are essential to a program designed to protect the waters of the state regardless of use classifications because they describe the fundamental conditions that all waters must meet.

It is the decision of the Commission to assign these standards as basic standards for Region 12 even though their presence is not generally suspected. Also, these numbers are not detectable using routine methodology, and there is some concern regarding the potential for monitoring requirements. This concern should be alleviated by Section 3.1.14 of the basic regulations, but there is uncertainty regarding the interpretation of those numbers by other entities. Regardless of these concerns, because these parameters are highly toxic, there is a need for regulating their presence in state waters. Because the Commission has determined that they have uniform applicability here, their inclusion as basic standards for the region accomplishes this purpose.

(e) In many cases, the numeric water quality standards are taken from the "Tables" appended to the basic regulations. These table values are used where actual ambient water quality data in a segment indicates that the existing quality is substantially equivalent to, or better than, the corresponding table values. This has been done because the table values are generally considered to protect the beneficial use classifications of the waters of the state.

Consistent with the basic regulations, the Commission has not assumed that the table values have presumptive validity or applicability in Region 12. This accounts for the extensive data in the record of ambient water quality; however, the Commission has found that the table values are generally sufficient to protect the use classifications. They have, therefore, been applied in the situations outlined in the preceding paragraph, as well as in those cases where there is insufficient data in the record to justify the establishment of different standards. The documentary evidence forming the basis for the table values is included in the record.

(f) In many cases, instream ambient water quality provides the basis for the water quality standards (See (g) below). In those cases where the classified uses presently exist or have a reasonable potential to exist despite the fact that instream data reflects ambient conditions of lower water quality than the table values, instream values have been used. In these cases, the evidence indicates that instream values are adequate to protect the uses. In those cases where temporary modifications are appropriate, instream values are generally reflected in the temporary modification and table values are reflected in the temporary modification and table values are reflected in the corresponding water quality standard. (The "goal" qualifier is then appended to the classification).

Cases in which water quality standards reflect these instream values usually involve the metal parameters. On many stream segments, elevated levels of metals are present due to natural or unknown causes, as well as mine seepage from inactive or abandoned mines. These sources are difficult to identify and impractical or impossible to control. The classified aquatic life uses may be impacted and/or may have acclimated to the condition. In either case, the water quality standards are deemed sufficient to protect the uses that are present.

(g) In assigning standards based on instream ambient water quality, a calculation is made based upon the mean (average) plus one standard deviation (x[BAR] + s) for all sampling points used on a particular stream segment. Since a standard deviation is not added to the water quality standard for purposes of determining compliance, this is a fair method as applied to discharges.

Levels that were determined to be below the detectable limits of the sampling methodology employed were averaged in as zero rather than at the detectable limit. This moves the mean down; but since zero is also used when calculating wasteload allocations, this method is not unfair to dischargers. A number of different statistical methods could have been used. All of them have pros and cons and the approach used is reasonable.

Metals present in water samples may be tied up in turbidity when the water is present in the stream. In this form they are not "available" to fish and may not be detrimental to aquatic life. Because the data of record does not distinguish as to availability, some deviation from table values, as well as the use of (x[BAR] + s) is further justified, because it is unlikely that the total value in the samples analyzed is in available form.

(h) No water quality standards are set below detectable limits for any parameter, although certain parameters may not be detectable at the limit of the standards using routine methodology; however, it must be noted that stream monitoring, as opposed to effluent monitoring, is generally not the responsibility of the dischargers but of the state. Furthermore, the purpose of the standards is to protect the classified uses, despite the inconvenience monitoring may impose.

Section 3.1.14 of the basic regulations states that "dischargers will not be required to regularly monitor for any parameters that are not identified by the division as being of concern". Generally, there is not requirement for monitoring unless a parameter is in the effluent guidelines for the relevant industry.

(a) Mainstem of the Colorado River, including all tributaries, lakes, and reservoirs within, or flowing into, Arapahoe National Recreation Area, including Grand Lake, Shadow Mountain Lake, and Lake Granby. (Upper Colorado River Basin, page 1, segment 2).

This segment was originally proposed for a "High Quality - Class 2" classification and has been classified for specific beneficial uses. In addition to the reasons given below, those found at Section (4)(f) above apply.

This is the only stream segment in this region where primary contact recreation is known to exist; however, the standard for fecal coliform that is necessary to protect the "Recreation - Class 1" use is not being met consistently. The segment has been classified "Recreation - Class 1" and the appropriate standard for fecal coliform has been assigned, but a temporary modification for this parameter has also been assigned.

Because of significant fecal coliform and nutrient problems in this area, the segment is not of such consistently high quality to justify a "High Quality" classification. There is a high level of human activity including existing point source discharges in this area, and it is a changing situation deserving of additional study, in view of continuing land and water resource development.

Downstream data indicates that the water quality is generally sufficient to support the use classifications. It is extremely important in this area to adopt water quality standards sufficient to protect these uses, and therefore, table values are assigned. A"High Quality" classification would not provide for this kind of protection at this time, since high quality waters are not being assigned specific numeric standards, in the absence of more complete data.

(b) Mainstem of the Blue River from the point of discharge of the Breckenridge Sanitation District wastewater treatment plant to Dillon Reservoir (Blue River Basin, page 3, segment 2).

The mainstem of the Blue River has been broken down into two segments because of current problems associated with the Breckenridge treatment plant. The Commission endorses the rationale of the staff located at pages 10 and 11 of the Water Quality Control Division Exhibit 2, except as to fecal coliform and ammonia. The change as to fecal coliform conforms to the reasoning outlined above.

The evidence is compelling regarding the need for a temporary modification for ammonia. The standard for unionized ammonia of 0.02 mg/l may be met now, but not consistently. Because of growth pressures in the area, more consistent violations of the standard in the near future are imminent.

A new plant is coming on line in the fall of 1981 or the winter of 1982. Significant questions presently exist regarding the location of the discharge and the kind of treatment that will be installed to meet the ammonia standard. Pending the completion of the new facility, a temporary modification is appropriate. The Breckenridge Sanitation District has recommended a temporary modification to 0.05 mg/l NH3 on the basis that phosphorus removal is presently capable of reducing the ammonia to this level. The Commission accepts this alternative proposal.

Because of the importance of this segment as a spawning area, close monitoring of these waters is necessary, and the Commission may have to re-examine this decision in the near future.

At the very least, the Commission recognizes its obligation to re-examine its decision with regard to the temporary modification within three years.

(c) Mainstem of Tenmile Creek, including all tributaries, lakes, and reservoirs, from the source to a point immediately above the confluence with West Tenmile Creek, except for the specific listing in Segment 14 (Blue River Basin, page 4, segment 12).

The reasoning contained in Water Quality Control Division Exhibit 2 on this stream segment is generally acceptable. Instream values in this segment are deemed sufficient to protect the classified uses. In assigning instream values, the staff used its own data plus that of the Division of Wildlife and Amax, Inc. Although the Climax discharge was not factored entirely, high numbers from samples taken during periods of bypass and high runoff were thrown out as being unrepresentative of ambient conditions. In stream values calculated without these high numbers are sufficient to protect the uses, and bypasses cannot be anticipated in the future.

The staff has recommended standards based on instream values and "goals" based on the "pilot plant data" i.e., data accumulated during the first six months of operation of the new treatment plant, while it was operating at the 50 percent of rated capacity. The staff's opinion is that these "goals" should be met with operation of the new plant. If the Commission were to adopt this approach, it would use the recommended "goals" as the standards, and set the recommended standards as temporary modifications (for copper, lead, and zinc); however, this approach was not taken because the data with respect to the new plant is not wholly adequate in determining what it will produce. This is an important concern since a significant portion of the flow of the stream goes through the plant. Therefore, instream values sufficient to protect the uses have been established and no temporary modifications have been granted.

The standards for metals are based on a hardness of less than 100 derived from the water quality data measured downstream. Basing the standards on a hardness of 400 which derives from effluent data would be unreasonable since ambient water quality for purposes of these standards is not to be measured at the point of discharge.

The water supply classification has been removed because there is not water supply use, and standards have been assigned from table values in accordance with the appropriate classifications, except in the metals categories.

(d) Mainstem of Tenmile Creek, including all tributaries, lakes, and reservoirs, from a point immediately above the confluent with West Tenmile Creek to Dillon Reservoir (Blue River Basin, page 5 segment 13).

The reasoning contained in the Water Quality Control Division Exhibit 2 on this stream segment is generally acceptable.

The water supply classification has been included because water quality is sufficient to protect this use.

The standards reflect instream water quality. Only cadmium and zinc represent values higher than the table values.

The Commission takes the same approach here with respect to the possibility of improved water quality as it does for the upper segment of Tenmile Creek.

(e) Mainstem of the Eagle River from the compressor house bridge at Belden to the confluence with Gore Creek (Eagle River Basin, page 6, segment 5).

This segment has been separated from the upper mainstem because instream monitoring indicates decidedly poorer water quality below Belden, although the uses are the same.

Although there is conflict in the evidence before the Commission regarding the "Aquatic Life - Class 1 - Cold" use, the Commission finds that the evidence is sufficient to show the presence of a variety of cold water aquatic life, although their numbers may be impacted. In addition, flow and streambed characteristics indicate that a variety of aquatic life can be supported and that the "Class 1" category is appropriate.

The "Water Supply" classification has been included because even though such use is not present within this segment, the classification is necessary to protect the Eagle-Vail water supply downstream, immediately below Gore Creek.

Inactive mines are at least partially responsible for water quality degradation in this segment. Some of these sites are of undermined ownership, and therefore, control of these sources cannot be predicted with any certainty. The control of some sources of pollution on this segment and the planned removal of the Cross Creek discharge by the New Jersey Zinc Company is expected but the extent of favorable impact of these efforts on water quality is unknown. Under no circumstances is water quality expected to improve beyond upstream quality, and therefore, some standard reflect those values (cadmium, copper, lead and zinc), and temporary modifications are not assigned.

Manganese and iron levels are set to protect the downstream water supply, and reflect table values.

(f) Mainstem of the Eagle River from Gore Creek to the confluence of the Colorado River (Eagle River Basin, page 7, segment 9).

The manganese problem on the Eagle River originates upstream of Gore Creek. For the reasons indicated above, the standard reflects the value necessary to protect the water supply use. That standard is not currently being met; however, control measures by the New Jersey Zinc Company are deemed sufficient to allow the standard to be met in the future. Therefore, a temporary modification has been granted. Standards for the other metals reflect instream values.

(g) Mainstem of Cross Creek from the source to the confluence with the Eagle River (Eagle River Basin, page 6, segment 7)

The record shows a conflict in the evidence concerning the data on ambient water quality which is the basis for the standards here. New Jersey Zinc Company presently discharges into Cross Creek, although an NPDES permit application is currently pending to move the discharge point to the Eagle River. The company's data indicates higher instream values than found by the Division. The Commission has adopted the Division's recommended standards because its analysis includes the most recent data, which was not used by the company. Also, difference sampling methods currently in use are found to be more accurate and they indicate lower values.

(h) Mainstem of Brush Creek from the source to the confluence with the Roaring Fork River (Roaring Fork River Basin, page 8, segment 4).

Although there is a conflict in the evidence regarding the existence of aquatic life downstream of th Snowmass Sanitation District discharge, the record supports the finding that a fishery is present. However, because the discharge sometimes constitutes the entire flow of the stream in the summer months, it is considered intermittent and assigned an "Aquatic Life - Class 2" classification. Nevertheless, standards have been assigned to protect the existing fishery.

The Snowmass Sanitation District has been funded for tertiary treatment but the technology is untested; therefore, a temporary modification has been assigned for ammonia.

Otherwise, ambient water quality data indicates that the table values are bing met and standards have been assigned accordingly.

(i) Mainstem of Oak Creek from the point of discharge of the Oak Creek wastewater treatment plant to the confluence with the Yampa River (Yampa River Basin, page 11, segment 7).

Although the "Aquatic Life - Class 1 - Cold" classification is appropriate, there is a limited variety of aquatic life below Oak Creek Drain. Because of this and because of the short distance between the Oak Creek discharge and the Oak Creek Drain, it is inappropriate to establish an ammonia standard at this time.

F I S C A L S T A T E M E N T

Stream Classifications and Water Quality Standards for the Upper Colorado River, the headwaters of the North Platte River, and the Upper Yampa River (Essentially those streams and water bodies in Eagle, Grand, Jackson, Pitkin, Routt and Summit Counties)

The Water Quality Control Commission is charged with the responsibility to conserve, protect, and improve the quality of state waters pursuant to C.R.S. 1973, 25-8-101 et seq.

The Commission is further charged to classify all waters of the State and to promulgate standards for any measurable characteristic of the water. (25-8-203 and 25-8-204). The above-titled document assigns use classifications and standards for the state waters in the listed areas in accordance with the "basic regulations" adopted May 22, 1979.

The measurable fiscal impacts which may be caused by these regulation are as follows:

- Cost of construction of increased capacity of municipal waste treatment facilities;

- Cost of construction of increased capacity of industrial waste treatment facilities;

- Cost of Operation & Maintenance of municipal enlargements;

- Cost of Operation & Maintenance of industrial enlargements; and

- Cost of instream monitoring and lab analysis for new parameters added by the standards.

Dischargers will not be required to do stream monitoring. Only those parameters which are limited by a discharge permit will be monitored. The state, federal, and local agencies now doing instream monitoring will have some increased cost; however, any additional frequency should be done to improve state surveillance and would be needed regardless of standard changes.

The Division has reviewed these regulations and determined that the following municipalities may need to construct additional facilities because of more stringent water quality standard and may have additional annual operation costs in the amounts shown:

The following industries or commercial establishments may have to construct and operate additional facilities to meet more stringent water quality standards and the additional costs are shown below:

The stream classifications and standards adopted by the Commission will protect the water uses primarily through control of potential point source pollution. Nonpoint source pollution from precipitation runoff will be controlled primarily from management practices which are in existence or will be implemented in the future. Future management practices need careful consideration and will be the result of 208 area-wide wastewater management plans developed by regional planning agencies and being updated annually. These plans involve local general purpose governments with general assistance from state government. Some of the possible nonpoint source pollution may be controlled through "Control Regulations" yet to be promulgated by the Commission. These types of controls could involve runoff from construction, mining activities, and urban areas. It is not certain what controls are needed at this time and there is no way that possible costs can be identified at this time.

Persons who benefit from standards which will protect existing and future anticipated uses can be identified as all persons benefiting from recreation, municipal water supply, and agriculture. These benefits are directly economic for agriculture, industry and municipalities who health benefit costs are reduced by having clean water, and are both economic and nonquantifiable for some uses such as fishing, recreation, and the aesthetic value of clean waters. Furthermore, benefits will result from human health protection and lack of debilitating disease. Figures have been developed for a recreation/fishing day which can be applied to that aspect of a water use; however, figures which have been developed for total recreation/fishing day uses have been developed statewide and could not be applied region-by-region or stream-by-stream.

The uses of water in this region are adequately protected by these standards. Most municipal treatment facilities and industrial facilities are currently adequate, or are already being upgraded, in order to meet previous requirements. Any additional facilities or expansions in this region will generally be caused by increased capacity required because of pollution growths or industrial enlargement. Industries are required by federal statute to meet effluent limitations described as "best available technology" by 1983 or 1984. For all major industries in this region, the water quality standards should not require treatment beyond these limitations.

No attempt can be made to identify future development costs as this type of data is not readily available.