DEPARTMENT OF ENVIRONMENTAL PROTECTION BUREAU OF WATER QUALITY PROTECTION. Policy for Permitting Surface Water Diversions

Transcription

1 DEPARTMENT OF ENVIRONMENTAL PROTECTION BUREAU OF WATER QUALITY PROTECTION DOCUMENT NUMBER: TITLE: Policy for Permitting Surface Water Diversions EFFECTIVE DATE: March 1, 1998 AUTHORITY POLICY: The Clean Streams Law of Pennsylvania This document provides a coordinated and consistent statewide process for permitting water diversions. PURPOSE: The purpose of this document is to permit surface water diversions taking into account protection of human health, aquatic life and other designated uses of the stream while balancing social, economic and environmental interests. APPLICABILITY: The guidance document applies to consulting engineers, geologists, and soils scientists on site selection, system design, and planning and permitting requirements for the land application of treated sewage and industrial wastewater. DISCLAIMER: The policies and procedures outlined in this guidance document are intended to supplement existing requirements. Nothing in the policies or procedures shall affect more stringent regulatory requirements. The policies and procedures herein are not an adjudication or a regulation. There is no intent on the part of the Department to give these rules that weight or deference. This document establishes the framework, within which DEP will exercise its administrative discretion in the future. DEP reserves the discretion to deviate from this policy statement if circumstances warrant. PAGE LENGTH: 14 pages. LOCATION: Volume 33, Tab / March 1, 1998 / Page 1

2 I. INTRODUCTION POLICY FOR PERMITTING SURFACE WATER DIVERSIONS This policy has been developed to provide a coordinated and consistent statewide process for permitting water diversions as it relates to interbasin transfer of wastewater discharges across watersheds. The policy results from a Pennsylvania Commonwealth Court Decision in DelAware Unlimited, et al. v. Department of Environmental Resources, et al., 508A.2d 348 (1986). That decision upholds an earlier Environmental Hearing Board (EHB) ruling that the diversion of water from one body to water to another requires National Pollution Discharge Elimination System (NPDES) permit. This policy paper describes the process by which NPDES permit requirements (discharge limitations and monitoring requirements) will be developed, taking into account: a. protection of human heath, aquatic life, and other designated stream uses. b. the balancing of social, economic, an environmental interest. c. existing versus proposed diversions. The policy for NPDES permitting of diversion discharges is in Section IV. Preceding Section IV, the relationship of NPDES permitting to other DEP permitting activities and a general description of the statutory basis and intent of the NPDES process are described. II. PERMITTING REQUIREMENTS AND INTERRELATIONSHIPS FOR WATER ALLOCATIONS AND DIVERSIONS The term water allocation is used by the Department with regard to regulating the right to divert water from streams, rivers, or other bodies of surface water (including springs) for public water supply use. A water diversion represents the withdrawal and transfer of surface water from one body of water into another for flow augmentation or by wastewater discharges crossing watershed boundaries. In this regard, the terms interbasin transfer and water diversion are generally used synonymously. The various regulatory permits and approvals which are involved in water diversions are listed in Table 1 below and described on Figure 1. Figure 2 describes the basic scenarios in which water allocations and diversions occur / March 1, 1998 / Page 2

3 TABLE 1 - PERMITS AND APPROVALS* RELATIVE TO WATER ALLOCATIONS AND DIVERSIONS Permits and Approvals Required a. Water Allocation Permit (If a public water supply is involved) b. Water Withdrawal/Interbasin Transfer Applicable Locations Regulatory Agency (See Fig. 1) 1, 3 DEP Bureau of Watershed Conservation (BWC) 1, 3 Delaware River Basin Commission (DRBC) Susquehanna River Basin Commission (SRBC) c. Water Obstructions Permits 1, 2, 3 DEP Bureau of Waterways Engineering (BWE) U.S. Army Corps of Engineers (COE) d. 401 Water Quality Certification (only if a federal action is involved) 1, 2, 3 DEP, Bureau of Water Quality Protection (BWQP) e. Public Water Supply 3 DEP Bureau of Water Supply Management (BWSM) f. NPDES Permit 2 DEP Bureau of Water Quality Protection (BWQP) *See Attachment I for a summary of each permit/approval process / March 1, 1998 / Page 3

4 FIGURE 1 - PERMIT AND APPROVAL REQUIREMENTS / March 1, 1998 / Page 4

5 A diversion may involve (but is not limited to) the following types of situations: A. Direct discharge to a reservoir located on the receiving stream. B. Direct discharge to the receiving stream. C. Discharge to an offstream reservoir which then discharges to the receiving stream. D. Discharge to an offstream reservoir which then discharges to the water user directly. FIGURE 2 - GENERAL OVERVIEW OF THE WATER DIVERSION PROCESS / March 1, 1998 / Page 5

6 Options A, B, and C in Figure 2 each represent a potential discharge of pollutants from the diverted stream to the receiving stream with subsequent withdrawal for use by one (or possibly several) water users and requires an NPDES permit from the Department. Option D represents a direct use of diverted water, usually by a single public water supply or other user. In this case, an NPDES permit for the diversion is not required. A detailed review of the regulatory basis of the permits that may be involved in a water diversion reveals a great deal of commonality in decision making among the various regulatory permitting/approval processes. This is particularly evident with regard to protection of human heath and the aquatic environment. This is schematically represented in Figure 3 which illustrates these interrelationships among the regulatory programs. FIGURE 3 - INTERRELATIONSHIPS AMONG PROGRAMS AFFECTING WATER ALLOCATIONS AND DIVERSIONS WATER QUALITY MANAGEMENT PROTECTION NPDES PERMITTING (BWQP) WATER SUPPLY PERMITTIN G (BWSM) WATER ALLOCATION PERMITTING (BWC) 401 WATER QUALITY CERTIFICATION (BWQP) WATER OBSTRUCTION PERMITTING (COE) WATER OBSTRUCTIO N PERMITTING (BWE) WATER RESOURCES MANAGEMENT / March 1, 1998 / Page 6

7 With the exception of public water supply permitting (which focuses exclusively on public health protection), all of the other permitting and approval processes are designed to take into account both public health and aquatic life protection impacts of the withdrawal, diversion, and discharge activities. Because of the close relationship among the various permits required by law for water allocations and diversions, the Department will coordinate the application review process for proposed allocations and diversions so that all issues will be addressed concurrently, and resulting permit actions will reflect the Department s overall position on proposed diversions. III. NPDES PERMITTING PROCESS A. Statutory Basis for NPDES Permitting The Federal Clean Water Act ( Act ) (33 USC Sections 1251 et seq.) establishes the National Pollutant Discharge Elimination Systems (NPDES) permit program. The act makes the discharge of any pollutant by any person unlawful unless an NPDES permit has been issued allowing the discharge. The discharge of any pollutant is defined as any addition of any pollutant to navigable waters from any point source. An point source includes any discernible, confined and discrete conveyance, including but not limited to any pipe, ditch, channel, tunnel, conduit from which pollutants are or may be discharged. It is under Pennsylvania s Clean Streams Law (35 P.S. Section et seq.) that the Department derives its authority to issue NPDES permits. B. Intent of NPDES Permitting As a key element in Pennsylvania s water quality management program, each NPDES permit issued to a point source discharger serves several important purposes: 1. It authorizes the permittee to discharge to waters of the Commonwealth. 2. It directs the permittee to achieve an acceptable quality of effluent prior to discharge. 3. It specifies the type and frequency of self-monitoring and reporting which the permittee must carry out to demonstrate that compliance with discharge requirements is being achieved. 4. Where applicable, it sets forth a schedule for achieving compliance with discharge requirements. 5. It serves as the basic legal instrument when enforcement action against a permittee becomes necessary / March 1, 1998 / Page 7

8 In addition to the above, each NPDES permit represents the culmination of applicable water quality management planning (areawide, basinwide and local) which forms the basis for allowing the discharge(s) to the water body to occur. C. Factors Considered in Issuing NPDES Permits The issuance of NPDES permits takes into account two basic factors: 1. The designated uses of the receiving stream and the water quality criteria necessary to protect those uses, and 2. The effluent quality necessary to meet established water quality criteria or minimum treatment requirement in order to protect designated stream uses. These factors are evaluated within a complex regulatory framework which is, generally, based on the assumption that the discharger has direct control over the volume of wastewater and levels of pollutants being discharged at any time. A diversion or interbasin transfer situation is unique in that the quality of the water to be diverted (and subsequently discharged to the receiving stream) is affected by a variety of naturally occurring and man-induced conditions which are not under the control of the diverter (discharger). As a result, a basic issue encountered in developing an NPDES permitting policy and process for water diversions is evaluation of the degree of public benefit vs. potential environmental impacts that are associated with diversions. However, the diverter must assure that the discharge does not cause a violation of water quality standards in the receiving stream. If designated uses are not being met, streams can be reclassified to a lower classification under certain conditions. Such reclassifications cannot be justified simply to accommodate a diversion discharge. However, if in the evaluation of a proposed or existing diversion discharge it is determined that a stream is improperly classified, a reclassification is possible. A reclassification requires a change to the Department s water quality standards regulations. The change is preceded by public participation and the regulatory review process mandated by State and Federal law and could take up to 2 years to accomplish the change. In evaluating the acceptability of a proposed diversion, the Department will take into account the water quality impact of the diversion on both the diverted and receiving streams. The Environmental Hearing Board (EHB) decision which requires the Department to issue NPDES permits for diversions states that the Department has a mandatory duty not to allow water quality standards to be exceeded as a result of the / March 1, 1998 / Page 8

9 diversion. The term water quality standards encompasses designated water uses and the water quality criteria necessary to protect those uses in both streams. Chapter 93 of the Department s Rules and Regulations (relating to Water Quality Standards) has established specific water quality criteria for various designated water uses in Pennsylvania. The water uses which are most critical to the election of appropriate instream water quality criteria are the statewide potable water supply (PWS) and various aquatic life uses (Warm Water Fishery - WWF, Trout Stocking Fishery - TSF, etc.). In addition to the water quality criteria, the requirements of Chapter 95.1 must be considered for diversions to streams classified for Special Protection. Fortunately, the water quality of most streams in Pennsylvania is better than the established numerical water quality criteria for those streams most of the time. There are some exceptions to this, however. The most notable exceptions are those streams which are acid impregnated (affected severely by acid drainage from abandoned coal mining activities). In streams being considered for diversion, there may be one or several water quality parameters for which the instream levels would violate numerical Chapter 93 water quality criteria during part of the year due to affects of point and non-point sources of pollution or to naturally-occurring conditions in the watershed. The impact of these parameters must be considered in the evaluation of proposed water diversions. Some of the water quality criteria established in Chapter 93 have been assigned specific numeric values, while others have been expressed as functions of their observable impact (i.e., toxicity affects) upon fish and other aquatic life. For example, the Chapter 93 criterion for aluminum is described as not to exceed 0.1 of the 96-hour LC 50 for representative impact species as determined through substantial available literature data or bioassay tests tailored to the ambient quality of the receiving waters. In addition to the listed criteria in Chapter 93, the general narrative water quality criteria in Section 93.6 applies: Section 93.6 General water quality criteria. (a) Water shall not contain substances attributable to point or nonpoint source waste discharges in concentrations or amounts sufficient to be inimical or harmful to the water uses to be protected or to human, animal, plant or aquatic life. (b) Specific substances to be controlled shall include, but shall not be limited to, floating debris, oil, grease, scum and other floating materials, toxic substances, pesticides, chlorinated hydrocarbons, carcinogenic mutagenic and teratogenic materials, and substances which produce color, tastes, odors, turbidity, or settle to form deposits / March 1, 1998 / Page 9

10 In determining the potential environmental impacts associated with diversions, consideration must also be given to Pennsylvania s Clean Streams Law definition of pollution. IV. PROPOSED POLICY ON NPDES PERMITTING OF WATER DIVERSIONS A. Proposed Diversions The Department will evaluate the expected water quality impact of a proposed diversion by reviewing the available long-term water quality data for both the diverted and receiving streams. Where long-term water quality data is not available, it will be the diverter s responsibility to provide at the Department s direction adequate data on Chapter 93 numeric criteria applicable to the diverted and receiving streams. Appropriate statistical trend analysis and water quality modeling techniques will be used to determine instream levels of Chapter 93 water quality parameters in the receiving and diverted streams that would result from the proposed diversion. The design conditions for this analysis would be the combination of the most critical flows, from a water quality standpoint, in both the receiving and diverted streams. The most critical flow may be low flow (Q 7-10 ) or another higher flow whose pollutant concentrations are at their highest levels. In determining parameters of concern, as a minimum, the parameters to be evaluated for diversion discharges include the following: - Dissolved Oxygen - Ammonia (NH 4 ) - Bioassay-based metals (Aluminum, Copper, Lead, Nickel, Zinc) - Phosphate (PO 4 ) (if evaluation of the diverted stream indicates there would be a PH 4 problem based on observed aquatic plant growth) - Temperature Other parameters which are identified from historical ambient water quality data or upstream discharger data, which have numerical limits in Chapter 93 or which may have an impact on public health or aquatic life, will be evaluated for their affect on the receiving stream. This evaluation will be conducted using best professional judgment and the best scientific information available on necessary water quality levels for public health and aquatic life protection in the receiving stream at the point of discharge / March 1, 1998 / Page 10

11 In addition, aquatic life impacts will be assessed by the applicant in conjunction with toxicity testing and/or other biological assessment techniques approved by the Department for waters of the diverted and receiving streams. Results will be submitted to the Department for review. If this assessment demonstrates an adverse impact on aquatic life, the parameters causing the problem will be identified by the applicant, and these parameters will be limited in the permit based on established effluent limit development procedures. If no impacts are demonstrated, no limits will be necessary as a result of this assessment. Of all these parameters, only those which will cause the combined receiving steams flow to violate Chapter 93 criteria, the requirements of Sections 93.5(c) and 95.1, or result in a human health or aquatic life impact (See Attachment II) will be considered parameters of concern and will be limited in the permit so as to prevent violations. Permit monitoring requirements will be tailored to the specific situation, but as a minimum, quarterly reporting on parameters with limits in the permit will be required plus a third quarter biological assessment for the first two years of the permit. In addition to an evaluation of the water quality impact of the diversion, the Department will establish technology based limits or other BMPs on a case-by-case basis using best professional judgment. Upon issuance of the NPDES permit but prior to initiation of the diversion, the permittee will be required to demonstrate in writing to the Department that the effluent limitations will be met and how. B. Existing Diversions There are a number of diversions in the state which have existed for many years and which are used for public and industrial water supply enhancement. For the purpose of this policy, diversions are considered existing if the diversion facilities are in place and operating prior to the date of establishment of this policy. In other words, it is the actual physical diversion of water that differentiates proposed from existing diversions. The existence of the diversion and the associated increases in stream flow below their respective points of discharge support the actual uses of the receiving and diverted streams for public water supply, aquatic life, recreation, and industrial uses. Prior to issuing the NPDES permits for these discharges, the Department will review historical ambient and discharge data for the diverted and receiving streams, and conduct a preliminary biological assessment to determine whether any adverse water quality impacts exist. If no adverse impacts or parameters of concern (see explanation in A. above) are identified, the applicants will be requested to submit applications defining discharge flow volumes for the diversions. Following public comment, if there / March 1, 1998 / Page 11

12 is no evidence of adverse water quality impact, the permits will be issued limiting flow (and temperature, if necessary) only. If it is concluded that there are parameters of concern or adverse water quality impacts, the permit applicant will evaluate and submit available water quality data above and below the point of intake and discharge for the receiving and diverted streams, focusing on the parameters of concern (see explanation in A. above). The applicant will also conduct an aquatic assessment in the receiving stream which will determine if any adverse impacts have been caused by the diversion and submit the results to the department. In the event that an existing diversion is found during the permit application review process to be causing a water quality standards violation in the receiving stream, discharge limits will be placed in the permit for the problem parameters. The process for determining if violations or problems exist, defining the parameters of concern and establishing permit limits is the same as that described for proposed diversions. A process and schedule to achieve compliance with these limit s will be negotiated in the context of a consent order and agreement or, as an alternative, the Department may initiate other enforcement action. In any enforcement action, the Department will consider the extent and sources of the existing pollution problems in the diverted stream and consider actions, including enforcement and/or treatment, that may be appropriate to improve water quality in the diverted stream. The NPDES permit will include monitoring requirements tailored to the specific situation, focusing on parameters of concern and, as a minimum, quarterly chemical reporting / March 1, 1998 / Page 12

13 Attachment I Individual Permitting Programs Water Allocation Permits In addition to looking at environmental impact of the proposed water allocation/diversion, the water allocation permit process takes into account the issue of water rights of other users of the diverted or receiving stream and the present and future needs of the public water supplier requesting the allocation. Downstream impacts as a result of the diversion on the diverted stream are also evaluated. Because of the interrelationships between water allocation permitting and public water supply permitting, the Department makes a determination of the potability of a proposed new source of surface water supply for which an allocation is requested. No allocation permit will be granted unless the applicant has provided sufficient information for the Department to determine such potability and the need for specific treatment requirements to achieve potability. Intrabasin and interbasin transfer analyses are also conducted to determine the location of return flows and any instream needs and downstream requirements below the withdrawal and/or discharge points. The Department relies upon information provided by the applicant as well as comments by other agencies or other interested parties for the determination of any such impacts in either the diverted stream or the receiving stream. Water Obstruction Permits Since diversions include the construction of structures in the waterway, water obstruction permits are required for the intake, discharge and any impoundment structures. The water obstruction permitting process as outlined in Chapter 105 of the Department s rules and regulations explicitly requires that issuance of permits must assure compliance with the standards and criteria of all laws administered by the Department, the Pennsylvania Fish Commission, and any river basin commission created by interstate compact. Issuance of obstruction permits must be consistent with the environmental rights and values secured by Pennsylvania s Constitution, Article I, Section 27, and with the Commonwealth s duties and trustee to conserve and maintain Pennsylvania s public natural resources. The water obstruction permitting process also requires coordination of the issuance of such permits with the other permitting processes conducted by the Department as well as other federal and state agencies. Water obstruction permit applications are subject to an environmental review and an investigation as to the need for balancing environmental, social and economic concerns. Public Water Supply Permits The public water supply permitting process is to assure safe drinking water will be served to the public by the water supply. Under that program, maximum contaminant levels (MCLs) and treatment technique requirements are at least as stringent as those promulgated under the Federal Safe Drinking Water Act for contaminants regulated under applicable federal regulations. The Environmental Quality / March 1, 1998 / Page 13

14 Board may adopt MCLs and treatment technique requirements more stringent than those promulgated under federal law, and many adopt MCLs or treatment technique requirements for contaminants for which MCLs or treatment technique requirements have not been promulgated under the federal law. In reviewing applications for public water supply permits, the Department focuses upon the following: 1. Adherence to standards relating to design and construction. These include provision of an adequate and reliable quantity and quality of water to the public. It includes assurance that water provided to the public will meet appropriate MCLs established by the Department. It also requires the applicant to make reasonable efforts to obtain the highest quality water sources available, and to take reasonable measures to protect each source from existing or foreseeable sources of contamination. 2. Compliance by the proposed project with applicable statues administered by the Commonwealth and river basin commissions created by interstate compact, and with federal environmental statues and regulations. 3. Present development conditions and the effects of reasonably foreseeable future development within the area of the project. The level of treatment required for a source of water depends upon the characteristics of the water source, the nature of the public water system, and the likelihood of contamination. For new surface sources and for existing surface sources which are planning to increase the quantity of water withdrawal, treatment generally consists of coagulation, flocculation, sedimentation, filtration and disinfection (unless other treatment would provide an equivalent quality of finished water and an equivalent level of protection). NPDES Permits The NPDES program is described in Section III of this document / March 1, 1998 / Page 14