ECONOMIC ANALYSIS OF THE PROPOSED WATER QUALITY STANDARDS RULE FOR PUERTO RICO October 2003 Prepared for:

U. S. Environmental Protection Agency Office of Water, Office of Water Science 1201 Constitution Avenue, N. W. 5th Floor Connecting Wing Washington, D. C. 20460 Prepared by:

Science Applications International Corporation 11251 Roger Bacon Drive Reston, VA 20190 EPA Contract No. SAIC Project Number 01 0833 04 2326 xxx October 2003 i Table of Contents Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ES 1 1.0 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 1.1 Background . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1 1.2 Purpose of the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2 1.3 Scope of the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 1.4 Organization of the Report . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 3 2.0 Baseline for the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1 2.1 Water Quality Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 1 2.2 Point Source Dischargers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 2 3.0 Description of the Proposed Rule . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 3.1 Water Quality Criteria and Designated Uses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 3.2 Potentially Impacted Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 1 4.0 Method for Estimating Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 4.1 Sample Facilities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 4.2 Identifying Potential Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 4.3 Estimating Costs of Controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2 4.4 Total Annual Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4 4.5 Potential Loading Reductions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 4 5.0 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1 5.1 Total Costs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1 5.2 Limitations of the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1 6.0 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1 APPENDICES Appendix A Facility Analyses Appendix B Total Annual Cost Calculations October 2003 ii List of Exhibits Exhibit ES 1. Comparison of Current Puerto Rico and Proposed EPA Criteria for Six Bays and Estuaries and the Coastal Ring . . . . . . . . . . . . . . . . . . . . . . . . . ES 2 Exhibit ES 2. Potential Costs Attributable to the Proposed Rule . . . . . . . . . . . . . . . . . . . . . ES 3 Exhibit 2 1. Puerto Rico Water Quality Criteria for Class SC Waters . . . . . . . . . . . . . . . . . 2 1 Exhibit 2 2. Summary of NPDES Permitted Direct Dischargers in Puerto Rico . . . . . . . . . . 2 2 Exhibit 3 1. Comparison of Current Puerto Rico and Proposed EPA Criteria . . . . . . . . . . . 3 1 Exhibit 3 2. Estimated Number of Facilities Potentially Affected by the Proposed Rule . . . . 3 2 Exhibit 4 1. Sample Facilities Evaluated . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1 Exhibit 4 2. Process Modification Cost Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 3 Exhibit 5 1. Potential Costs Attributable to the Proposed Rule . . . . . . . . . . . . . . . . . . . . . . 5 1 Exhibit 5 2. Limitations of the Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 October 2003 iii List of Acronyms BOD Biochemical oxygen demand CWA Clean Water Act DMR Discharge monitoring report EPA Environmental Protection Agency EO Executive Order EQB Environmental Quality Board mgd Million gallons per day mL milliliter NPDES National Pollutant Discharge Elimination System NTU Nephelometric turbidity units O& M Operation and maintenance PCS Permit compliance system POTW Publicly owned treatment works PRWQSR Puerto Rico Water Quality Standards Rule TSS Total suspended solids WQS Water quality standards October 2003 Executive Summary ES   1 Executive Summary The U. S. Environmental Protection Agency ( EPA) is proposing water quality standards ( WQS) applicable to waters in the Commonwealth of Puerto Rico. This report provides estimates of potential incremental costs that point source dischargers may experience as a result of the proposed rule.

In August 1990, the Commonwealth of Puerto Rico adopted revisions to the Puerto Rico Water Quality Standards Rule ( PRWQSR). The revisions were sent to EPA on September 21, 1990, with a caveat from the Chairman of the Puerto Rico Environmental Quality Board ( EQB) that the transmittal may not be the final submittal, because EQB was to have a subsequent public hearing on November 1, 1990. Therefore, EPA did not act on these revisions immediately.

The requisite certification from the Commonwealth's Secretary of Justice was ultimately submitted to EPA on February 25, 2002. Upon receipt of this certification, EPA took final action on all new and revised provisions of the 1990 PRWQSR on March 28, 2002. These revisions included 11 separate new or revised provisions. The 1990 revisions to the PRWQSR, however, did not include any changes to the designation of specific water body segments, including any upgrades of waters from Class SC ( secondary contact recreation) to Class SB ( primary contact recreation).

On March 28, 2003, EQB submitted additional revisions to the PRWQSR. These revisions included the reclassification of ten bays and estuaries previously classified as Class SC waters to Class SB ( Article 2.1.3). EPA approved these revisions on June 26, 2003. However, the revisions to the PRWQSR did not address the 6 bays and the coastal ring ( i. e., coastal waters from 500 meters to 3 miles) still designated Class SC. Consequently, on February 20, 2002, a complaint was filed in the U. S. District Court for the District of Puerto Rico by three environmental groups: CORALations, American Littoral Society, and the American Canoe Association. In this action, the plaintiffs alleged, among other things, that certain actions by EPA personnel had triggered a mandatory duty under Section 303( c) of the CWA to prepare and propose regulations setting forth a revised water quality standard for any coastal waters that remained classified SC. On August 11, 2003, the Court ordered EPA to prepare and publish new or revised water quality standards for those coastal waters which are currently classified as Class SC waters.

EPA is proposing to establish a new Federal use designation for primary contact recreation use and applicable water quality criteria to protect primary contact recreation for selected water bodies in Puerto Rico. The current coliform criteria for Class SC waters are intended to be protective of secondary contact recreation, and the remainder of the criteria are intended to protect other uses, such as aquatic life protection or human health. Therefore, the new Federal use does not affect any of these criteria designation, except for the bacteriological criteria. The proposed bacteriological criteria are the same as the Commonwealth's criteria for fecal coliform and enterococci associated with the Class SB use ( Section 3.2.2 of the PRWQSR). Exhibit ES 1 shows EPA's proposed criteria and provides the Commonwealth's current criteria for comparison. 1Potentially affected facilities may include facilities that do not discharge directly to affected waters. EPA assumed that facilities discharging two miles or less upstream of the six bays and the coastal ring could potentially impact the downstream water body.

October 2003 Executive Summary ES   2 Exhibit ES 1. Comparison of Current Puerto Rico and Proposed EPA Criteria for Six Bays and Estuaries and the Coastal Ring1 Designated Use Puerto Rico Criteria Proposed EPA Criteria Coliforms 10,000 colonies/ 100 mL of total coliform. 2,000 colonies/ 100mL of fecal coliforms. Not more than 20% of fecal coliform samples shall exceed 4,000 colonies/ 100 mL. 35 colonies / 100 mL enterococci density. 200 colonies/ 100mL of fecal coliforms Not more than 20% of fecal coliform samples shall exceed 400 colonies/ 100 mL.

1. Includes Mayaguez Bay from Punta Guanajibo to Punta Algarrobo, Yabucoa Port, Guayanilla and Tallaboa Bays from Cayo Parguera to Punta Verraco, Ponce Port from Punta Carenero to Punta Cuchara, San Juan Port from the mouth of Río Bayamón to Punta El Morro, and the coastal ring ( i. e., coastal waters 500 meters to 3 miles).

In evaluating the impact of its proposed rule, EPA calculated the cost of reducing fecal coliform levels based on current Puerto Rico standards to levels that would be required under EPA's proposed more stringent standards. The water quality criteria and uses in EPA's proposed rule may impact facilities that discharge to affected waters. EPA assumed that only facilities that have the potential to affect ( i. e., cause an increase in fecal coliform levels) the 6 bays for which EPA is designating a new primary contact recreation use or the coastal ring ( i. e., coastal waters from 500 meters to 3 miles) may be impacted. 1 EPA identified these facilities by overlaying facilities in its permit compliance system ( PCS) database with the potentially affected waters and their tributaries currently designated for a Class SC use using geographic information system software. EPA assumed that only wastewater treatment plants or military facilities with similar effluent characteristics ( i. e., facilities having the potential to discharge fecal coliforms) could potentially be affected by the proposed rule.

EPA identified a total of 32 facilities ( 20 majors and 12 minors) that may be affected by the proposed primary contact designated use, and evaluated a sample of facilities from this group for potential cost impacts. To select a sample, EPA stratified the universe by discharge type ( major, minor) and category ( municipal, military). EPA evaluated the two major municipal facilities with the greatest flow, thus ensuring that the facilities with the largest potential costs would be evaluated. EPA also evaluated the only major facility in the military category. For the remaining facilities, EPA chose a random sample to represent discharger type and category.

EPA estimated the most cost effective control strategy for each sample facility to achieve compliance with the proposed criteria on a case by case basis. EPA assumed that projected effluent limits for fecal coliform would be applied as criteria end of pipe ( a monthly geometric mean of 200 colonies/ 100 mL and not more than 20% of samples exceeding 400 colonies/ 100 mL) because the facilities' current permits apply the existing criteria in the same manner. EPA assumed that a sample facility would incur costs if average monthly effluent concentrations ( or existing permit limit, whichever is smaller) indicate that the facility would not be in compliance with the most stringent criterion. October 2003 Executive Summary ES   3 EPA determined potential compliance with the projected limit for each sample facility based on the relative magnitude of the maximum average monthly values, the pattern of occurrence of such values ( i. e., when maximum values occurred), and current treatment performance characteristics [ e. g., biochemical oxygen demand ( BOD) and total suspended solids ( TSS) concentrations, compliance with current permit]. EPA assumed that facilities exceeding their current limits would install the necessary controls for compliance with current standards, and would incur costs for additional treatment process optimization to comply with the projected limit. For facilities that comply with their current permit limits but would not comply with the projected limit, EPA also assumed that process optimization of their chlorination process would be necessary for compliance with the projected limit.

EPA extrapolated the results for each type and category of sample facility to all facilities in the universe. EPA estimated that the total annual potential cost of the proposed rule is approximately $ 2.7 million, and that the total annual costs will result in pollutant loading reductions of 1.86 x 1015 fecal coliform colonies. Fecal coliforms are bacteria that, when present, indicate contamination of receiving waters by mammalian feces, including human feces. At high numbers of fecal coliform bacteria per volume of water, there is a high probability that human pathogens ( disease causing organisms) are also present, resulting in an increased risk of disease following contact. Ingestion of high concentrations of fecal coliform bacteria can also lead directly to human illness. The reductions in the number of fecal coliform bacteria as a result of the proposed rule will therefore reduce the risk of human disease from discharge of waste from wastewater treatment facilities.

Exhibit ES 2 provides a summary of the number of potentially affected facilities and the estimated costs associated with the proposed rule.

Exhibit ES 2. Potential Costs Attributable to the Proposed Rule ( millions of $ 2003) 1 Category Facilities Evaluated ( Total Affected) Total Capital Annual O& M Total Annual Costs2 Major Municipal 6 ( 19) $ 2.5 $ 2.4 $ 2.6 Minor Municipal 2 ( 10) $ 0.5 $ 0.1 $ 0.1 Major Military 1 ( 1) $ 0.0 $ 0.0 $ 0.0 Minor Military 1 ( 2) $ 0.1 $ 0.0 $ 0.0 Total 10 ( 32) $ 3.2 $ 2.4 $ 2.7 Note: Detail may not add to total due to rounding. O& M = operation and maintenance. 1. Costs for evaluated facilities extrapolated to all potentially affected facilities. 2. Annual costs represent total potential costs for all facilities affected by the proposed rule. Total annual costs are the sum of annual capital costs ( i. e., total capital costs that have been annualized at 7% over 20 years) and annual O& M expenditures. October 2003 1.0 Introduction 1   1 1.0 Introduction The U. S. Environmental Protection Agency ( EPA) is proposing water quality standards ( WQS) applicable to waters of the United States in the Commonwealth of Puerto Rico. This report presents EPA's analysis of potential costs associated with the proposed rule. Specifically, the report provides estimates of potential incremental costs that direct point source dischargers may experience as a result of the proposed rule through changes to their National Pollutant Discharge Elimination System ( NPDES) permit limits.

1.1 Background Section 303 ( 33 U. S. C. 1313) of the Clean Water Act ( CWA) directs States to adopt water quality standards to protect the public health and welfare, enhance the quality of water and serve the purposes of the CWA. Under Section 303, States are required to develop WQS for waters within their boundaries. Section 303( c) provides that WQS shall include the designated use or uses for the water and criteria necessary to protect those uses. The designated uses to be considered by States in establishing water quality standards are specified in the CWA and include public water supplies, propagation of fish and wildlife, recreation, agricultural uses, industrial uses, and navigation. States are required to review their water quality standards at least once every three years and, if appropriate, revise or adopt new standards. The results of this triennial review must be submitted to EPA, and EPA must approve or disapprove any new or revised standards.

Water quality standards establish the " goals" for a water body through the establishment of designated uses. Designated uses, in turn, determine what water quality criteria apply to specific water bodies. Section 101( a)( 2) of the CWA establishes as a national goal " water quality which provides for the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water," wherever attainable. These national goals are commonly referred to as the " fishable/ swimmable" goals of the Act. Section 303( c)( 2)( A) requires water quality standards to " protect the public health and welfare, enhance the quality of water, and serve the purposes of this Act." EPA's regulations at 40 CFR 131 interpret and implement these provisions by requiring that water quality standards provide for fishable/ swimmable uses unless those uses have been shown to be unattainable. The mechanism in EPA's regulations used to overcome this presumption is a use attainability analysis.

In August 1990, the Commonwealth of Puerto Rico adopted revisions to the Puerto Rico Water Quality Standards Rule ( PRWQSR). The revisions were sent to EPA on September 21, 1990, with a caveat from the Chairman of the Puerto Rico Environmental Quality Board ( EQB) that the transmittal may not be the final submittal, because EQB was to have a subsequent public hearing on November 1, 1990. Therefore, EPA did not act on these revisions immediately because of the public hearing, and because the requisite certification ( required by 40 CFR 131.6( e)) from the Commonwealth's Secretary of Justice was not submitted with the revisions.

From 1991 to 1993, EPA Region 2 worked with EQB on a series of draft revisions to the PRWQSR. However, these drafts were never adopted by Puerto Rico. In 1992, EPA included October 2003 1.0 Introduction 1   2 Puerto Rico in the National Toxics Rule, mainly because EPA did not consider the 1990 revisions to be officially adopted.

The requisite certification from the Commonwealth's Secretary of Justice was ultimately submitted to EPA on February 25, 2002. Upon receipt of this certification, EPA took final action on all new and revised provisions of the 1990 PRWQSR on March 28, 2002. These revisions included 11 separate new or revised provisions. The 1990 revisions to the PRWQSR, however, did not include any changes to the designation of specific water body segments, including any upgrades of waters from Class SC ( secondary contact recreation) to Class SB ( primary contact recreation).

On March 28, 2003, EQB submitted additional revisions to the PRWQSR. These revisions included the reclassification of ten bays and estuaries previously classified as Class SC waters to Class SB ( Article 2.1.3), including: Aguadilla Bay ( from Punta Boquerón to Punta Borinquen); Arecibo Bay ( from Punta Maracayo to Punta Caracoles); Fajardo Bay ( from Playa Sardinera to Playa de Fajardo); Roosevelt Roads ( from Punta Cabra de Tierra to Punta Cascajo); Port of Naguabo ( from Playa de Naguabo to El Morrillo); Jobos Bay and Laguna de la Mareas ( from Punta Rodeo to Punta Colchones); Guánica Bay inland waters north of the mouth of the river; Port of Dewey in Culebra; and Port of Isabel Segunda in Vieques and Puerto Real in Vieques between Cayo de Tierra and Cayo Real. EPA approved these revisions on June 26, 2003.

While the March 28, 2003 revisions to the PRWQSR did address 10 bays and estuaries that were previously classified as Class SC waters by reclassifying them to Class SB, Puerto Rico recognized that the 6 bays and the coastal ring ( i. e., coastal waters from 500 meters to 3 miles) still needed to be addressed. In an effort to address these remaining Class SC waters, EQB, in its State Fiscal Year 2003 CWA Section 604( b) Consolidated Workplan, committed to develop a plan that would outline a schedule for data collection and analysis, and identify the applicable regulatory actions for these waters. EQB is currently completing this plan.

However, on February 20, 2002 a complaint was filed in the U. S. District Court for the District of Puerto Rico by three environmental groups: CORALations, American Littoral Society, and the American Canoe Association. In this action, the plaintiffs alleged, among other things, that certain actions by EPA personnel had triggered a mandatory duty under Section 303( c) of the CWA to prepare and propose regulations setting forth a revised water quality standard for any coastal waters that remained classified SC. Consequently, the Court, in its August 11, 2003 Opinion and Order, ordered EPA to prepare and publish new or revised water quality standards for those coastal waters which are currently classified as Class SC waters.

1.2 Purpose of the Analysis Under Executive Order ( EO) 12866 ( 58 FR 51735, October 4, 1993), the Agency must determine whether a regulatory action is " significant" and, therefore, subject to the requirements of the order ( drafting an economic analysis and submitting it for review by the Office of Management and Budget). EO 12866 defines " significant" as those actions likely to lead to a rule having an annual effect on the economy of $ 100 million or more, or adversely and materially affecting a sector of 2 Agricultural and other nonpoint source discharges, as well as storm water discharges, are technically difficult to model and evaluate for potential cost impacts because they are intermittent, highly variable, and occur under different hydrologic or climatic conditions than continuous discharges from industrial and municipal facilities.

October 2003 1.0 Introduction 1   3 the economy, productivity, competition, jobs, the environment, public health or safety, or state, local, or tribal governments or communities.

EPA's proposed rule does not establish any requirements directly applicable to regulated entities. Although implementation may ultimately result in new or revised NPDES permit conditions for some dischargers, EPA's action does not impose any of these requirements. In addition, EPA does not anticipate an annual effect on the economy of $ 100 million or more. Nonetheless, consistent with the intent of EO 12866, EPA typically estimates ( within the limits of these uncertainties) the potential costs to NPDES permitted facilities, and the associated pollutant reductions, that ultimately may result from its water quality standards rules to inform the public regarding these potential impacts.

1.3 Scope of the Analysis EPA's analysis addresses NPDES permitted facilities discharging to water bodies affected by the proposed rule. The types of affected facilities may include industries and publicly owned treatment works ( POTWs) discharging sanitary wastewater to surface waters in the Commonwealth ( i. e., point sources). EPA did not consider the potential costs for sources that it does not have direct authority to regulate through the NPDES program ( i. e., nonpoint sources, such as agricultural nonpoint sources). 2 1.4 Organization of the Report This report is organized as follows. Section 2 outlines the baseline for the analysis by describing the current State designated uses and criteria, and the point sources that are subject to that criteria Section 3 provides a description of the proposed rule and the potentially affected dischargers. Section 4 summarizes the method for estimating costs, and Section 5 presents the results of the analysis. Several appendices provide detailed information on the sample facilities and the estimation of costs. October 2003 2.0 Baseline for the Analysis 2   1 2.0 Baseline for the Analysis The section describes the baseline conditions relevant to evaluating the potential impact of EPA's proposed rule. EPA calculated the incremental costs of the rule's provisions as the cost of reducing fecal coliform levels based on current Puerto Rico standards to levels that would be required under EPA's proposed more stringent standards. Thus, this section describes the current Commonwealth standards, and the existing dischargers in the Commonwealth.

2.1 Water Quality Standards Exhibit 2 1 summarizes Puerto Rico's current criteria for waters designated as Class SC. Coastal waters designated as Class SC are " intended for uses where the human body may come in indirect contact with the water ( such as fishing, boating, etc.), and for use in propagation and preservation of desirable species, including threatened or endangered species." EQB applies the Class SC designation in coastal waters from the zone subject to the ebb and flow of tides ( e. g., mean sea level) to10.3 nautical miles seaward.

Exhibit 2 1. Puerto Rico Water Quality Criteria for Class SC Waters Parameter Current Puerto Rico Criteria Dissolved Oxygen Not less than 4 mg/ L ( except when natural conditions prohibit attainment).

Coliforms The geometric mean of a series of representative samples ( at least 5 samples) taken sequentially shall not exceed 10,000 colonies/ 100 mL of total coliforms or 2,000 colonies/ 100mL of fecal coliforms. Not more than 20% of fecal coliform samples shall exceed 4,000 colonies/ 100 mL.

pH Between 7.3 and 8.5 ( except when caused by natural phenomena).

Color Shall not be altered by other than natural phenomena except when it can be proven that such change in color is harmless to biota and aesthetically acceptable.

Turbidity Shall not exceed 10 NTU.

Taste and Odor Shall not be present in amounts that will render any undesirable taste or odor to edible aquatic life.

Sulfates Shall not exceed 2,800 mg/ L ( applies to estuarine waters).

Surfactants as MBAS Shall not exceed 500 µ g/ L.

NTU = nephelometric turbidity units MBAS = methylene blue active substances Under current WQS, Class SC criteria apply to segments of the following coastal waters in the zone subject to the ebb and flow of tides ( mean sea level) to 10.3 nautical miles seaward:

° Mayaguez Bay from Punta Guanajibo to Punta Algarrobo. October 2003 2.0 Baseline for the Analysis 2   2 ° Yabucoa Port ° Guayanilla and Tallaboa Bays from Cayo Parguera to Punta Verraco ° Ponce Port from Punta Carenero to Punta Cuchara ° San Juan Port from the mouth of Río Bayamón to Punta El Morro.

2.2 Point Source Dischargers EPA's Permit Compliance System ( PCS) database indicates that there are 593 facilities permitted to discharge to Puerto Rican surface waters. EPA classifies 86% of these facilities as minor dischargers [ facilities discharging less than 1 million gallons per day ( mgd) and not likely to discharge toxic pollutants in toxic amounts] or general permit facilities ( general permits are permits issued to an entire category of dischargers). Exhibit 2 2 provides a summary of all permits by industry and permit type.

Exhibit 2 2. Summary of NPDES Permitted Direct Dischargers in Puerto Rico Standard Industrial Classification Number of Facilities1 Majors Minors Construction 15 General Contractors and Operative Builders  1 16 Heavy Construction  1 Manufacturing 20 Food and Kindred Products 5 6 21 Tobacco Products  1 27 Printing and Publishing  1 28 Chemicals and Allied Products 9 2 29 Petroleum and Coal Products 6 1 32 Stone, Clay, and Glass Products 5  34 Fabricated Metal Products  2 36 Electronic and Other Electronic Equipment 1  Transportation and Public Utilities 49 Electric, Gas, and Sanitary Services; except 4952 12 106 4952 Sewerage Services ( POTWs) 38 33 Wholesale Trade 50 Wholesale Trade   Durable Goods 1  51 Wholesale Trade   Nondurable Goods 3 2 Finance, Insurance, and Real Estate 65 Real Estate  1 Services 70 Hotels and Other Lodging Places  3 79 Amusement and Recreational Services  2 80 Health Services 1 2 82 Educational Services  21 84 Museums, Botanical, Zoological Gardens  2 Exhibit 2 2. Summary of NPDES Permitted Direct Dischargers in Puerto Rico Standard Industrial Classification Number of Facilities1 Majors Minors October 2003 2.0 Baseline for the Analysis 2   3 87 Engineering, Accounting, Research, Management, and Related Services  1 Public Administration 91 Executive, Legislative and General Government, except Finance 1 1 92 Justice, Public Order, and Safety 1 2 97 National Security and International Affairs 1 3 No SIC Code ( blank in PCS)  7 Total 84 201 Source: U. S. EPA ( 2003a). `` = none. 1. There are also 308 general permit dischargers that EPA did not include in the analysis. Most of these dischargers are construction sites and storm water discharges. Data for general permit facilities are extremely limited, and flows from such facilities are usually negligible. Also, EPA could not determine if any of these facilities discharge to affected stream segments because location information are not available in PCS. 3Potentially affected facilities may include facilities that do not discharge directly to an affected waters. EPA assumed that facilities discharging two miles or less upstream of the six bay and the coastal ring could potentially impact the downstream water body.

October 2003 3.0 Description of the Proposed Rule 3   1 3.0 Description of the Proposed Rule This section describes EPA's proposed rule and the facilities that discharge to affected waters that, depending on EPA Region 2' s implementation of EPA's proposed rule, may be affected by the proposed WQS.

3.1 Water Quality Criteria and Designated Uses EPA is proposing to establish a new Federal use designation for primary contact recreation use and applicable water quality criteria to protect primary contact recreation for selected water bodies in Puerto Rico. The current coliform criteria for Class SC waters are intended to be protective of secondary contact recreation. The remainder of the criteria applicable to Class SC designated waters are intended to protect other uses, such as aquatic life protection through the maintenance of a sufficient level of dissolved oxygen in the water column, or human health from the consumption of fish based on the level of toxic pollutants in the water and the fish tissue. Therefore, the new Federal use designation does not affect any of these criteria, except for the bacteriological criteria. The proposed bacteriological criteria are the same as the Commonwealth's criteria for fecal coliform and enterococci associated with the Class SB use ( Section 3.2.2 of the PRWQSR). Exhibit 3 1 shows EPA's proposed criteria and provides the Commonwealth's current criteria for comparison.

Exhibit 3 1. Comparison of Current Puerto Rico and Proposed EPA Criteria for Six Bays and Estuaries and the Coastal Ring1 Designated Use Puerto Rico Criteria Proposed EPA Criteria Coliforms 10,000 colonies/ 100 mL of total coliform. 2,000 colonies/ 100mL of fecal coliforms. Not more than 20% of fecal coliform samples shall exceed 4,000 colonies/ 100 mL. 35 colonies / 100 mL enterococci density. 200 colonies/ 100mL of fecal coliforms Not more than 20% of fecal coliform samples shall exceed 400 colonies/ 100 mL.

1. Includes Mayaguez Bay from Punta Guanajibo to Punta Algarrobo, Yabucoa Port, Guayanilla and Tallaboa Bays from Cayo Parguera to Punta Verraco, Ponce Port from Punta Carenero to Punta Cuchara, San Juan Port from the mouth of Río Bayamón to Punta El Morro, and the coastal ring ( i. e., coastal waters 500 meters to 3 miles).

3.2 Potentially Impacted Facilities The water quality criteria and uses in EPA's proposed rule may impact facilities discharging to affected waters. EPA identified these facilities using its PCS database. In doing so, EPA assumed that only facilities that have the potential to affect ( i. e., cause an increase in fecal coliform levels) the 6 bays for which EPA is designating a new primary contact recreation use or the coastal ring ( i. e., coastal waters from 500 meters to 3 miles) may be impacted. 3 EPA identified these facilities by overlaying PCS facilities with the potentially affected waters and their tributaries currently designated for a Class SC use using geographic information system software. October 2003 3.0 Description of the Proposed Rule 3   2 EPA assumed that only wastewater treatment plants or military facilities with similar effluent characteristics ( i. e., facilities having the potential to discharge fecal coliforms) could potentially be impacted by the proposed rule. Exhibit 3 2 summarizes the universe of potentially affected facilities by type and category.

Exhibit 3 2. Estimated Number of Facilities Potentially Affected by the Proposed Rule Category Number of Facilities Major Minor Total Military 1 2 3 Municipal 19 10 29 Total 20 12 32 October 2003 4.0 Method for Estimating Costs 4   1 4.0 Method for Estimating Costs This section describes EPA's method for estimating potential costs to the NPDES permitted facilities identified in Section 3.

4.1 Sample Facilities EPA identified a total of 32 facilities ( 20 majors and 12 minors) that may be affected by the proposed primary contact designated use. EPA evaluated a sample from this group for potential cost impacts associated with the proposed rule. To select a sample, EPA stratified the universe by discharge type ( major, minor) and category ( POTW, military). EPA evaluated the two major municipal facilities with the greatest flow, thus ensuring that the facilities with potential for the largest costs would be evaluated. EPA also evaluated the only major facility in the military category. For the remaining facilities, EPA chose a random sample to represent discharger type and category. Exhibit 4 1 summarizes the sample facilities selected by type and category.

Exhibit 4 1. Sample Facilities Evaluated NPDES No. Name Flow ( mgd) Type Category PR0021555 Puerto Nuevo Regional Wastewater Treatment Plant 72 Major Municipal PR0023752 Carolina Wastewater Treatment Plant 45 Major Municipal PR0023728 Bayamon Regional Wastewater Treatment Plant 30 Major Municipal PR0025445 Guayama Regional Wastewater Treatment Plant 10 Major Municipal PR0025399 Humacao Regional Sewage Treatment Plant 8 Major Municipal PR0021679 Vega Baja Wastewater Treatment Plant 2.2 Major Municipal PR0020486 Guanica Wastewater Treatment Plant 0.8 Minor Municipal PR0023442 Boquerón Wastewater Treatment Plant 0.3 Minor Municipal PR0020010 U. S. Naval Station  Roosevelt Roads 2 Major Military PR0020044 Fort Allen Training Annex ( Puerto Rico National Guard) 0.2 Minor Military 4.2 Identifying Potential Controls EPA estimated the most cost effective control strategy for each sample facility to achieve compliance with the proposed criteria on a case by case basis. EPA assumed that projected effluent limits for fecal coliform would be applied as criteria end of pipe ( a monthly geometric mean of 200 colonies/ 100 mL and not more than 20% of samples exceeding 400 colonies/ 100 mL) because the facilities' current permits apply the existing criteria in the same manner. EPA assumed that a sample facility would incur costs if average monthly effluent concentrations ( or existing permit limit, whichever is smaller) indicate that the facility would not be in compliance with the most stringent criterion.

EPA evaluated each facility's potential compliance with projected permit limits based on available monthly average fecal coliform values from its PCS database. If monthly average values are not October 2003 4.0 Method for Estimating Costs 4   2 available, EPA evaluated potential compliance based on maximum monthly values. Note that the existing and proposed fecal coliform criteria should be measured as a geometric mean of five consecutive, representative samples. However, EPA did not have the actual data that the average monthly values in PCS are calculated from so that a geometric mean could be used. Instead, EPA used the average value, which results in a conservative estimate of compliance ( i. e.., tending to overstate the potential magnitude of reductions needed for compliance).

EPA determined potential compliance with the projected limit for each sample facility based on the relative magnitude of the maximum average monthly values, the pattern of occurrence of such values ( e. g., when maximum values occurred), and current treatment performance characteristics [ e. g., biochemical oxygen demand ( BOD) and total suspended solids ( TSS) concentrations, compliance with current permit]. EPA assumed that facilities exceeding their current limits would install the necessary controls for compliance with current standards, and would incur costs for additional treatment process optimization to comply with the projected limit. For facilities that comply with their current permit limits but would not comply with the projected limit, EPA also assumed that process optimization of their chlorination process would be necessary for compliance with the projected limit.

Treatment process optimization refers to measures that facilities can implement to enhance the operating efficiency of their wastewater treatment process. Process optimization usually involves process analysis and process modifications. Process analysis is an investigation of the performance limiting factors of the treatment process, and is a key factor in achieving optimum treatment efficiency. Performance limiting factors for chlorination may include operator training, response to changes in wastewater quality, treatment efficiency of other individual treatment units, maintenance activities, automation, and process control testing. The cost of process analysis includes the cost of additional monitoring throughout the treatment process, and a treatment performance evaluation.

Process modifications include activities short of adding new treatment technology units ( conventional or unconventional) to the treatment train. For chlorination, process modifications might include adjusting the chlorine dose, improving mixing conditions ( e. g., addition of baffles to chlorine contract chamber), improving BOD and TSS removal efficiencies, increasing contact time, equalizing flow, training operators, and installing automation equipment including necessary hardware and software. Several months of adjustments may be needed to achieve a desired level of process optimization due to potential difficulties ( e. g., synchronizing chlorine dose with varied levels of pollutant concentrations such as BOD, TSS, and flow).

4.3 Estimating Costs of Controls EPA determined the necessary controls on point sources to reduce fecal coliform concentrations to the required level by first evaluating whether low cost control options would be feasible, and then considering more costly controls, if necessary. EPA considered the lowest cost option, adjustment of existing treatment ( process optimization), to be feasible if literature indicates that the existing treatment process can achieve the revised effluent limit. October 2003 4.0 Method for Estimating Costs 4   3 EPA assumed that all the sample facilities would pursue process optimization to reduce fecal coliform levels because they all currently chlorinate their effluents prior to discharge, and literature indicates that chlorination, when operated properly, should produce effluent fecal coliform concentrations below 200 colonies/ 100 mL ( WERF, 1995).

For facilities exceeding their current permit limits, EPA first estimated the controls necessary for compliance with the current permit limit. EPA then determined if those controls would also enable the facility to meet the projected effluent limit. If those controls enable compliance with the projected limit, EPA assumed that the facility would not incur costs associated with the proposed rule ( i. e., all control costs are associated with meeting the current standards). Otherwise, EPA estimated the incremental costs associated with reducing fecal coliform levels to the projected limit, that is, the additional costs required ( after compliance with the State's current standards) to achieve a new limit based on EPA's proposed standards.

EPA estimated the cost of process optimization for point sources using available estimates from the literature, and developed estimates for each facility based on the reductions needed and current treatment processes. For most of the facilities, EPA does not have specific information regarding the chlorination process, such as chlorine dose used, volume of contact chamber, contact time, mixing conditions, type of chlorine used, or maintenance procedures. Therefore, EPA assumed that facilities are operating at a minimal treatment level ( e. g., using the lowest recommended chlorine dose or contact time for type of treatment processes, poor mixing, cleaning once every two years).

EPA estimated process analysis costs assuming a two month analysis of the facility's treatment processes. EPA assumed that a wastewater treatment plant operator would work full time for three months monitoring the wastewater at different stages throughout the treatment plant and determining the process modifications necessary. EPA used a labor rate of $ 15.79 for a water and liquid waste treatment plant and system operator in Puerto Rico, which includes employer benefits ( BLS, 2002). Thus, EPA assumed that process analysis costs of $ 7,579 would be incurred ( 480 hours x $ 15.79/ hour), and annualized these capital costs at 7% over 20 years.

EPA estimated costs for process modification costs for each facility based on current treatment performance. Modification costs may include additional chlorine and chlorine storage facilities, cleaning contact basins, installing of baffles to assist mixing in the contact basin, and increasing contact basin volume ( i. e., increasing contact time). Each component may have capital or operation and maintenance ( O& M) costs. Exhibit 4 2 summarizes the type of costs associated with each component and the source of the cost estimates.

Exhibit 4 2. Process Modification Cost Components Modification Costs Incurred Unit Costs Source Increase chlorine dose Additional chlorine Additional chlorine storage space $ 1,280/ cylinder of chlorine $ 51.47/ sq. ft. storage U. S. EPA ( 2003b)

Increase maintenance Additional 6 15 labor hrs/ mgd for cleaning basins $ 15.79/ hour WERF ( 1995); BLS ( 2002) Exhibit 4 2. Process Modification Cost Components Modification Costs Incurred Unit Costs Source October 2003 4.0 Method for Estimating Costs 4   4 Improve mixing Installation of baffles in chlorination contact basin $ 36.49/ sq. ft. of baffle U. S. EPA ( 2003b)

Increase contact time Additional contact basins $ 339/ cu. yd. U. S. EPA ( 2003b)

sq. ft. = square foot cu. yd. = cubic yard 4.4 Total Annual Costs To estimate total annual costs, EPA extrapolated the results for each type and category of sample facility to all facilities in the universe. To do this, EPA calculated a per facility cost by dividing the total costs for each type and category by the number of sample facilities in that group. EPA then multiplied the per facility cost by the total number of facilities.

4.5 Potential Loading Reductions EPA estimated fecal coliform loading reductions as the difference between the estimated baseline concentration and the projected limit. EPA estimated loadings in number of colonies per year by multiplying the pollutant concentration ( in colonies/ 100 mL) by the facility effluent flow ( in mgd), a conversion factor ( 3.79 x 107), and 365 days per year. The estimated loading reduction is based on the difference between the average of the monthly effluent values that exceed the projected limit ( or the current effluent limit if the facility is not currently in compliance with their current limit) and the projected effluent limit. October 2003 5.0 Results 5   1 5.0 Results This section presents the results of the analysis, and describes the limitations and uncertainties associated with these results.

5.1 Total Costs EPA estimated that the total annual potential cost of the proposed rule is approximately $ 2.7 million. Exhibit 5 1 provides a summary of the number of potentially affected facilities, and the estimated costs associated with the proposed rule. Appendix A provides detailed analyses for each of the sample facilities. Appendix B shows the extrapolation of costs for all potentially affected dischargers.

Exhibit 5 1. Potential Costs Attributable to the Proposed Rule ( millions of $ 2003) 1 Category Facilities Evaluated ( Total Affected) Total Capital Annual O& M Total Annual Costs2 Major Municipal 6 ( 19) $ 2.5 $ 2.4 $ 2.6 Minor Municipal 2 ( 10) $ 0.5 $ 0.1 $ 0.1 Major Military 1 ( 1) $ 0.0 $ 0.0 $ 0.0 Minor Military 1 ( 2) $ 0.1 $ 0.0 $ 0.0 Total 10 ( 32) $ 3.2 $ 2.4 $ 2.7 Note: Detail may not add to total due to rounding. 1. Costs for evaluated facilities extrapolated to all potentially affected facilities. 2. Annual costs represent total potential costs for all facilities affected by the proposed rule. Total annual costs are the sum of annual capital costs ( i. e., total capital costs that have been annualized at 7% over 20 years) and annual O& M expenditures.

EPA estimated that the total annual costs would result in pollutant loading reductions of 1.86 x 1015 fecal coliform colonies. Fecal coliforms are bacteria that, when present, indicate contamination of receiving waters by mammalian feces, including human feces. At high numbers of fecal coliform bacteria per volume of water, there is a high probability that human pathogens ( disease causing organisms) are also present, resulting in an increased risk of disease following contact. Ingestion of high concentrations of fecal coliform bacteria can also lead directly to human illness. The reductions in the number of fecal coliform bacteria as a result of the proposed rule will therefore reduce the risk of human disease from discharge of waste from wastewater treatment facilities.

5.2 Limitations of the Analysis EPA's estimate is subject to a number of limitations associated with the data available for the analysis. These uncertainties are described in Exhibit 5 2. October 2003 5.0 Results 5   2 Exhibit 5 2. Limitations of the Analysis Limitation/ Assumption Potential Impact on Costs Comment EPA did not have specific information on the chlorination process ( e. g., chlorine dose, volume of contact basin, frequency of maintenance) at the sample facilities.

EPA assumed that facilities are currently operating at minimum treatment levels ( e. g., 5 mg/ L for secondary treatment plants, 60 minute contact time).

EPA used average monthly fecal coliform data from its PCS database to determine compliance with current and projected effluent limits.

EPA PCS data are summarized. EPA would have preferred to use the actual data that the average monthly data are calculated from so that a geometric mean instead of an average value could be used ( since the fecal coliform limit is specified as a geometric mean).

The universe of potentially affected facilities includes facilities that discharge two miles or less upstream of the affected waters.

Some facilities that discharge upstream of the affected water bodies may not contribute to an instream exceedance of fecal coliform.

EPA applied the proposed fecal coliform criteria end of pipe ( i. e., did not allow dilution).

The Commonwealth may have information that shows that applying the criteria end of pipe would not be necessary.

Key: + = Costs are potentially overstated October 2003 6.0 References 6   1 6.0 References Bureau of Labor Statistics ( BLS). 2002. 2001 Occupational Employment Survey ( OES) State Occupational Employment and Wage Estimates, Puerto Rico. Online at http:// www. bls. gov/ oes/ 2001/ oes_ pr. htm.

U. S. EPA. 2003a. Permit Compliance System ( PCS) Database. Accessed August 22, 2003. Online at http:// www. epa. gov/ enviro/ html/ pcs/ adhoc. html.

U. S. EPA. 2003b. Chlorine Disinfection Model of the WBS Based Cost Models for Drinking Water Treatment Technologies. Final Draft.

Water Environment Research Foundation ( WERF). 1995. Comparison of UV Irradiation to Chlorination: Guidance for Achieving Optimal UV Performance. Project 91 WWD 1. Appendix A: Facility Analyses Bayamon Regional Wastewater Treatment Plant Boquerón Wastewater Treatment Plant Carolina Regional Wastewater Treatment Plant Fort Allen Training Annex Guanica Wastewater Treatment Plant Guayama Regional Wastewater Treatment Plant Humacao Regional Sewage Treatment Plant Puerto Nuevo Regional Wastewater Treatment Plant U. S. Naval Station  Roosevelt Roads Vega Baja Wastewater Treatment Plant October 2003 Appendix A. Facility Analyses A   1 Bayamon Regional Wastewater Treatment Plant Facility Description The Bayamon Regional Wastewater Treatment Plant ( NPDES No. PR0023728) is located in Cataño, Puerto Rico. The facility, which began operation in 1983, is owned by the Puerto Rico Aqueduct and Sewer Authority and operated by the Compañía de Aguas de Puerto Rico. The facility treats wastewater from Bayamon Cataño and parts of Guaynabo, Rio Piedras, Toa Alta, and Toa Baja. EPA classifies the discharge as a major discharge. The facility has a design flow of 30 mgd and discharges about 7,364 feet from the shore into the Atlantic Ocean.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of mechanical bar screening and grit removal, primary clarification with chemical addition, and chlorination. Sludge is removed from sedimentation tanks and macerated by grinders before being sent to sludge thickeners. Thickened sludge is pumped to a tanker truck for offsite disposal.

Summary of Effluent Data and Limits Exhibit A 1 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 2 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 1. Effluent Data Summary, Bayamon RWWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 38 27 5 695 42 2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 2. Compliance Summary, Bayamon RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 42 2,000 None 200 2 out of 38 Exhibit A 2. Compliance Summary, Bayamon RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 October 2003 Appendix A. Facility Analyses A   2 1. Represents the average of the average monthly values from January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of values exceed 400 colonies/ 100 mL.

Controls Needed The facility is in compliance with the current effluent limit for fecal coliform. Only two observation are greater than the projected effluent limit ( values of 285 and 695 colonies/ 100 mL in June 2000 and June 2003, respectively), and the average of the average monthly values is well below the projected limit. Therefore, EPA assumed that the facility would most likely be in compliance with the proposed rule because of the infrequency of small exceedances of the projected limit. October 2003 Appendix A. Facility Analyses A   3 Boquerón Wastewater Treatment Plant Facility Description The Boquerón Wastewater Treatment Plant ( NPDES No. PR0023442) is located in San Juan, Puerto Rico. The facility treats sanitary wastewater and serves the communities of Boquerón and Villa Taína. EPA classifies the discharge as a minor discharge. The facility discharges an average of 0.25 mgd to Boqueròn Bay.

Treatment Processes The facility's 2000 permit renewal application indicates that current treatment processes consist of aeration, sedimentation, clarification, and chlorination. Sludge is aerobically digested and stabilized in drying beds.

Summary of Effluent Data and Limits Exhibit A 3 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 4 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 3. Effluent Data Summary, Boquerón WWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 41 39 2 24,895 2,056 2 2002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 400 colonies/ 100 mL.

Exhibit A 4. Compliance Summary, Boquerón WWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Fecal Coliform ( colonies/ 100 mL) 2,056 200 27 out of 41 200 1. Represents the average of the average monthly values from January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL.

Controls Needed October 2003 Appendix A. Facility Analyses A   4 The facility is not in compliance with its current permit limit for fecal coliforms, which is identical to the projected effluent limit under the proposed rule. Therefore, once in compliance with the current permit limit, the facility would also be in compliance with the projected effluent limit and, would not incur costs associated with EPA's proposed rule. October 2003 Appendix A. Facility Analyses A   5 Carolina Regional Wastewater Treatment Plant Facility Description The Carolina Regional Wastewater Treatment Plant ( NPDES No. PR0023752) is located in Barrio Torrecilla Baja at Loíza, Puerto Rico. The facility is owned by the Puerto Rico Aqueduct and Sewer Authority and operated by the Compañía de Aguas de Puerto Rico. The facility treats wastewater from the municipalities of Carolina, Loíza, Canóvanas, Trujillo Alto, and Río Grande. EPA classifies the discharge as a major discharge. The facility discharges an average of 45 mgd about 6,200 feet from shore into the Atlantic Ocean.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of mechanical bar screening, grit removal, primary clarification with chemical addition, and chlorination. Sludge is removed from the clarifiers by telescopic valves and macerated and pumped to holding tanks. The sludge is then dewatered by a belt filter press.

Summary of Effluent Data and Limits Exhibit A 5 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 6 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliform does not allow for dilution.

Exhibit A 5. Effluent Data Summary, Carolina RWWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 37 35 2 245 20 2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 6. Compliance Summary, Carolina RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 20 2,000 None 200 1 out of 37 Exhibit A 6. Compliance Summary, Carolina RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 October 2003 Appendix A. Facility Analyses A   6 1. Represents the average of the average monthly values from January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of the values exceed 400 colonies/ 100 mL.

Controls Needed Exhibit A 6 indicates that the facility is in compliance with the current fecal coliform limit. Only one observation ( value of 245 colonies/ 100 mL) is greater than the projected effluent limit. Therefore, the facility most likely would not incur costs associated with the proposed rule. October 2003 Appendix A. Facility Analyses A   7 Fort Allen Training Annex Facility Description The Fort Allen Training Annex ( NPDES No. PR0020044) is located in Juana Diaz, Puerto Rico. The facility is an army training facility operated by the Puerto Rico National Guard for training reserve soldiers. The facility provides treatment of domestic sanitary wastewater and discharges a maximum of 0.17 mgd to the La Colectora Channel, a tributary to the Caribbean Sea. EPA classifies the discharger as a minor discharge.

Treatment Processes A facility's 2000 permit renewal application indicates that current treatment processes consist of mechanical bar screens, sedimentation, clarification, aeration, and chlorination. Sludge is digested and dried on drying beds.

Summary of Effluent Data and Limits Exhibit A 7 summarizes the maximum monthly effluent data for fecal coliform from EPA's PCS database from March 2000 through June 2003. Exhibit A 8 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliform does not allow for dilution.

Exhibit A 7. Effluent Data Summary, Fort Allen Training Annex1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL) Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 22 20 2 6,683 577 2 2,0002 Source: U. S. EPA ( 2003a). 1. Maximum monthly values from March 2000 to June 2003. 2. Represents an average monthly limit. The facility's current permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 8. Compliance Summary, Fort Allen Training Annex Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 765 2,000 2 out of 22 200 5 out of 22 1. Represents the average of the maximum monthly values from March 2000 to June 2003. 2. Violations of current permit limit based on maximum monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies. 100 mL) based on maximum monthly values. Less than 20% of the values exceed 400 colonies/ 100 mL.

Controls Needed October 2003 Appendix A. Facility Analyses A   8 Exhibit A 8 indicates that the facility may not be in compliance with the current effluent limit for fecal coliform. However, EPA assumed that the facility would not need to install treatment controls for compliance with the current limit because the facility's discharge monitoring reports ( DMRs) indicate that one of the exceedances is due to a mechanical malfunction in the chlorination system and low pressure at the potable water system, and the other exceedance is most likely the result of poor TSS removal due to scheduled maintenance and clean up.

The facility is not currently in compliance with the projected effluent limit. Based on maximum monthly values, the facility would exceed the projected limit about 23% of the time. Specific information on the chlorination system at the facility such as chlorine dose, mixing conditions, and contact tank volume is not available, however, effluent data ( e. g., TSS, BOD, and flow data) do not indicate that other treatment processes other than the chlorination system are contributing to the increased fecal coliform levels. Therefore, EPA assumed that process optimization of the chlorination system would enable the facility to comply with the projected effluent limit.

Exhibit A 9 summarizes the estimated control costs associated with reducing fecal coliform to the required levels. Costs include process analysis to determine the cause of the exceedances ( through monitoring and evaluation), and process modifications including increasing the chlorine dose from 10 mg/ L to 20 mg/ L, improving mixing conditions through the addition of baffles, increasing contact time from 60 minutes to 90 minutes ( additional contact basin volume), and increasing the frequency of maintenance and cleaning of the contact basins to prevent bacteria build up from once every 2 years to twice a year.

Exhibit A 9. Summary of Compliance Costs, Fort Allen Training Annex Cost Component Capital Costs O& M Costs Total Annual Costs1 Process Analysis $ 7,579  $ 715 Process Modifications: Increase Chlorine Dose Improve Mixing Increase Contact Time Increase Maintenance $ 45,873 $ 2,020 $ 4,7460  $ 3,840   $ 121 $ 8,170 $ 191 $ 448 $ 121 Total $ 60,218 $ 3,961 $ 9,645 Sources: U. S. EPA ( 2003b); BLS ( 2002); WERF ( 1995). 1. Capital costs annualized at 7% over 20 years plus O& M costs October 2003 Appendix A. Facility Analyses A   9 Guanica Wastewater Treatment Plant Facility Description The Guanica Wastewater Treatment Plant ( NPDES No. PR0020486) is located in Guanica, Puerto Rico. The facility is owned by the Puerto Rico Aqueduct and Sewer Authority and operated and maintained under contract by Ondeo de Puerto Rico. The facility treats domestic wastewater from the town of Guanica. EPA classifies the discharge as a minor discharge. The facility has a design flow of 0.8 mgd and discharges to Guanica Bay.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of preliminary screening and grit removal, aeration, aerobic digestion, clarification, and chlorination. Sludge is discharged to sludge drying beds or a mobile belt filter press for dewatering. Dried sludge is disposed of in a landfill.

Summary of Effluent Data and Limits Exhibit A 10 summarizes the average monthly effluent data for fecal coliform from EPA's PCS database from July 2000 through June 2003. Exhibit A 11 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 10. Effluent Data Summary, Guanica WWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 36 34 2 2,382 120 2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from July 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 11. Compliance Summary, Guanica WWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 120 2,000 1 out of 36 200 4 out of 36 Exhibit A 11. Compliance Summary, Guanica WWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 October 2003 Appendix A. Facility Analyses A   10 1. Represents the average of the average monthly values from July 200 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of the projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of values exceed 400 colonies/ 100 mL.

Controls Needed Exhibit A 11 indicates that the facility is most likely in compliance with its current effluent limit ( the only exceedance occurred in July 2001). However, the facility would not be in compliance with its projected fecal coliform limit. The facility's current chlorination process is operated by an automatic flow controller that adjusts the amount of chlorine input into the contact chambers according to changes in effluent flow. The effluent flow is measured at the chlorine contact chamber outlet. The facility would most likely need to increase the dose of chlorine associated with varying effluent flow for compliance with the projected effluent limit. Exhibit A 12 summarizes the control costs necessary to reduce fecal coliform to the required levels. Costs include process analysis to determine the necessary dose and increasing the chlorine dose from 5 mg/ L to 15 mg/ L ( plus the additional storage space).

Exhibit A 12. Summary of Compliance Costs, Guanica WWTP Cost Component Capital Costs O& M Costs Total Annual Costs1 Process Analysis $ 7,579  $ 715 Process Modifications: Increase Chlorine Dose $ 91,747 $ 15,360 $ 24,021 Total $ 99,326 $ 15,360 $ 24,736 Sources: U. S. EPA ( 2003b); BLS ( 2002). 1. Capital costs annualized at 7% over 20 years plus O& M costs. October 2003 Appendix A. Facility Analyses A   11 Guayama Regional Wastewater Treatment Plant Facility Description The Guayama Regional Wastewater Treatment Plant ( NPDES No. PR0025445) is located in Guayama, Puerto Rico. The facility discharges an average of 10 mgd to the Caribbean Sea.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of screening and grit removal, primary sedimentation, biofiltration, clarification, and chlorination. Sludge is digested and sent to stabilization ponds. It is then dried in drying beds and hauled to a sanitary landfill.

Summary of Effluent Data and Limits Exhibit A 13 summarizes the average monthly effluent data for fecal coliform from EPA's PCS database from April 2001 through June 2003. Exhibit A 14 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 13. Effluent Data Summary, Guayama RWWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 26 23 3 24,739 2,001 2 2,0002 Source: U. S. EPA ( 2003a) 1. Average monthly values from April 2001 to June 2003 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 14. Compliance Summary, Guayama RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 2,001 2,000 4 out of 26 200 6 out of 27 1. Represents the average of the average monthly values from April 2001 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of values exceed 400 colonies/ 100 mL.

Controls Needed October 2003 Appendix A. Facility Analyses A   12 Exhibit A 14 indicates that the facility is not in compliance with its current permit limit. However, all of the exceedances of the current limit occurred in 2001, and the facility has not had an exceedance of its current limit in the last 2 years. Therefore, is likely now meeting its current effluent limit for fecal coliform.

Since December 2001 the facility has exceeded the projected limit on 2 occasions ( values of 221 and 228 colonies/ 100 mL in consecutive months). Therefore, EPA assumed that only minor process optimization ( e. g., improvements in maintenance, monitoring of chlorine dose) would be necessary for compliance with projected limit. EPA assumed that such measures would not measurably increase operating costs, and the facility would not incur costs associated with the proposed rule. October 2003 Appendix A. Facility Analyses A   13 Humacao Regional Sewage Treatment Plant Facility Description The Humacao Regional Sewage Treatment Plant ( NPDES No. PR0025399) is located in Rio Abajo, Puerto Rico. The facility is owned by the Puerto Rico Aqueduct and Sewer Authority and is operated and maintained by the Professional Services Group. The facility has a design capacity of 8.24 mgd and treats sanitary and industrial wastewater from Humacao, Naguabo, and Las Piedras. EPA classifies the discharge as a major discharge. The facility discharges to the Caribbean Sea.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of bar screening, grit removal, primary sedimentation, biofiltration, final clarification, and chlorination. Sludge is gravity thickened or anaerobically digested, dewatered in drying beds and sent to an onsite landfill.

Summary of Effluent Data and Limits Exhibit A 15 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 16 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 15. Effluent Data Summary, Humacao RSTP1 Parameter Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL) Total Detect Nondetect Maximum Mean Minimum Average Monthly 41 41  312 61 5.2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 16. Compliance Summary, Humacao RSTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 61 2,000 None 200 2 out of 41 1. Represents the average of the average monthly values from January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of the values exceed 400 colonies/ 100 mL. October 2003 Appendix A. Facility Analyses A   14 Controls Needed Exhibit A 16 indicates that the facility is currently in compliance with its current effluent limit, but may not be in compliance with the projected limit. However, both exceedances of the projected limit occurred before March 2001 ( values of 280 and 312 colonies/ 100 mL in April 2000 and February 2001, respectively). Based on the most recent effluent conditions ( i. e., March 2001 to June 2003), the facility would likely be in compliance with the projected effluent limit. Therefore, EPA assumed that the facility would not incur costs associated with the proposed rule. October 2003 Appendix A. Facility Analyses A   15 Puerto Nuevo Regional Wastewater Treatment Plant Facility Description The Puerto Nuevo Regional Wastewater Treatment Plant ( NPDES No. PR0021555) is located in San Juan, Puerto Rico. The facility is owned by the Puerto Rico Aqueduct and Sewer Authority and is operated by the Compañía de Aguas de Puerto Rico. The facility began operation in 1957 and treats wastewater from the municipalities of San Juan, Trujillo Alto, and portions of Bayamon, Guayanbo, and Carolina. EPA classifies the discharge as a major discharge. The facility has an average hydraulic loading of 72 mgd and discharges about 7,300 feet from the shore into the Atlantic Ocean.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of mechanical bar screening, grit removal, primary clarification, and chlorination. Sludge is dewatered with a rotating sludge thickener mechanism and pumped to a tanker truck for offsite disposal.

Summary of Effluent Data and Limits Exhibit A 17 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 18 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit for fecal coliforms does not allow for dilution.

Exhibit A 17. Effluent Data Summary, Puerto Nuevo RWWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 38 34 4 35,512 1,078 2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 18. Compliance Summary, Puerto Nuevo RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 1,078 2,000 1 out of 38 200 3 out of 38 Exhibit A 18. Compliance Summary, Puerto Nuevo RWWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 October 2003 Appendix A. Facility Analyses A   16 1. Represents the average of the average monthly values from January 200 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of the values exceed 400 colonies/ 100 mL.

Controls Needed Exhibit A 18 indicates that the facility is most likely in compliance with its current effluent limit for fecal coliform. ( Hard copy DMR data from the facility indicate that the single exceedance of the current limit was the result of an insufficient chlorine dose.) However, the facility may not be in compliance with the projected effluent limit. The facility's DMR data indicate that two of the three exceedances are due to a chlorine demand greater than the supplied chlorine dose. Therefore, EPA assumed that increasing the chlorine dose when the chlorine demand increases would enable the facility to comply with the projected limit. Exhibit A 19 summarizes the control costs associated with reducing fecal coliforms to the required levels. Costs include monitoring of the influent and effluent to the chlorine contact chambers ( e. g., process analysis) and the additional chlorine costs to increase the dose from 10 mg/ L to 15 mg/ L ( plus the additional storage space).

Exhibit A 19. Summary of Compliance Costs, Puerto Nuevo RWWTP Cost Component Capital Costs O& M Costs Total Annual Costs1 Process Analysis $ 7,579  $ 715 Process Modifications: Increase Chlorine Dose $ 504,608 $ 701,440 $ 749,075 Total $ 512,187 $ 701,440 $ 749,790 Sources: U. S. EPA ( 2003b); BLS ( 2002). 1. Capital costs annualized at 7% over 20 years plus O& M costs. October 2003 Appendix A. Facility Analyses A   17 U. S. Naval Station Roosevelt Roads Facility Description The U. S. Naval Station Roosevelt Roads ( NPDES No. PR0020010) is located in Ceiba, Puerto Rico. The U. S. Naval Station operates and maintains facilities for naval surface and air operations of the Atlantic Fleet through use of its airfield and ship yards. The base has three wastewater treatment plants ( Forrestal, Capehart, and Bundy) that treat domestic, commercial, and industrial wastewater. Outfall 001 ( Forrestal WWTP) has an average flow of 0.38 mgd and treats wastewater generated in the Waterfront Service Area, including the pesticide and pest control building, the engine service station, the pier, torpedo, vehicle, and aircraft washrack areas, sandblasting and spray painting area, batteries handling areas, and the fire fighting training area. Outfall 001 is discharged to the Ensenda Honda. Outfall 002 ( Capehart WWTP) has an average flow of 0.14 mgd and treats sanitary wastewater from the local high school and surrounding Navy housing area. Outfall 003 ( Bundy WWTP) has an average flow of 0.46 mgd and treats sanitary wastewater as well as wastewater from the vehicle maintenance area. Both outfalls 002 and 003 discharge to the Vieques Passage. EPA classifies the facility as a major discharger.

Treatment Processes The facility's 2002 permit renewal application indicates that current treatment processes for outfall 001 consist of screening and grit removal, flow equalization, preaeration, oil recovery, primary clarification, trickling filtration, secondary clarification, nitrification, denitrification, chlorination, dechlorination, and cascading aeration. Current treatment processes for outfall 002 consist of grit removal and washing, comminutor, aeration, clarification, nitrification, denitrification, chlorination, dechlorination, and cascading aeration. Current treatment processes for outfall 003 consist of screening and grit removal, primary clarification, trickling filtration, secondary clarification, nitrification, dentrification, chlorination, dechlorination, and cascading aeration. Sludge from each outfall is aerobically digested and dried in sludge drying beds.

Summary of Effluent Data and Limits Exhibit A 20 summarizes average monthly effluent fecal coliform data from EPA's PCS database for each outfall from January 2000 through June 2003. Exhibit A 21 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limits for fecal coliforms do not allow for dilution.

Exhibit A 20. Effluent Data Summary, U. S. Naval Station Roosevelt Roads1 Outfall Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum 001 ( Forrestal) 41 41  20 8.5 2 2,0002 002 ( Capehart) 39 39  45 8.3 2 2,0002 Exhibit A 20. Effluent Data Summary, U. S. Naval Station Roosevelt Roads1 Outfall Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum October 2003 Appendix A. Facility Analyses A   18 003 ( Bundy) 35 35  20 8.2 2 2,0002 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 21. Compliance Summary, U. S. Naval Station Roosevelt Roads Outfall Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit2 Projected Limit Exceedances4 001 ( Forrestal WWTP) 8.5 2,000 None 200 None 002 ( Capehart WWTP) 8.3 2,000 None 200 None 003 ( Bundy WWTP) 8.2 2,000 None 200 None 1. Represents the average of the average monthly values from January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. Less than 20% of the values exceed 400 colonies/ 100 mL.

Controls Needed Exhibit A 21 indicates that the facility is currently in compliance with the current and projected effluent limits for fecal coliform. Therefore, the facility would not incur costs associated with the proposed rule. October 2003 Appendix A. Facility Analyses A   19 Vega Baja Wastewater Treatment Plant Facility Description The Vega Baja Wastewater Treatment Plant ( NPDES No. PR000021679) is located in Humacao, Puerto Rico. The facility is owned by the Puerto Rico Aqueduct and Sewer Authority and operated and maintained by Compañia de Aguqas de Puerto Rico. The facility began operation in 1971, and in 1988 a package activated sludge plant was added. Both facilities are currently in use. The facility treats domestic wastewater from Vega Baja, and discharges an average of 2.2 mgd to Cabo Caribe Creek. EPA classifies the discharge as a major discharge.

Treatment Processes Information provided by EPA Region 2 indicates that current treatment processes consist of communitors and grit removal, flow splitting, primary clarification, activated sludge, biofiltration, final sedimentation, and chlorination. Sludge is anaerobically digested and dried in drying beds or a belt filter press.

Summary of Effluent Data and Limits Exhibit A 22 summarizes average monthly effluent data for fecal coliform from EPA's PCS database from January 2000 through June 2003. Exhibit A 23 compares current effluent conditions to the current and projected effluent limits for fecal coliform under the proposed rule. EPA assumed that the criteria would apply end of pipe because the current effluent limit does not allow for dilution.

Exhibit A 22. Effluent Data Summary, Vega Baja WWTP1 Pollutant Number of Observations Summary of Detected Values ( colonies/ 100 mL) Current Limit ( colonies/ 100 mL)

Total Detect Nondetect Maximum Mean Minimum Fecal Coliform 41 38 3 397,423 40,9242 3 2,0003 Source: U. S. EPA ( 2003a). 1. Average monthly values from January 2000 to June 2003. 2. Average is underestimated because 4 values are reported as greater than a number ( e. g., > 160,000), and EPA assumed the value was at the detection limit ( e. g., 160,000). 3. Represents an average monthly limit. The permit also prohibits more than 20% of the samples from exceeding 4,000 colonies/ 100 mL.

Exhibit A 23. Projected Effluent Limits, Vega Baja WWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 Fecal Coliform ( colonies/ 100 mL) 40,924 2,000 14 out of 41 200 19 out of 41 Exhibit A 23. Projected Effluent Limits, Vega Baja WWTP Pollutant Effluent Value1 Current Limit Current Limit Exceedances2 Projected Limit3 Projected Limit Exceedances4 October 2003 Appendix A. Facility Analyses A   20 1. Represents the average of the average monthly values January 2000 to June 2003. 2. Violations of current permit limit based on average monthly values. 3. Represents an average monthly limit. Under the proposed rule, the limit would also prohibit more than 20% of the samples from exceeding 400 colonies/ 100 mL. 4. Violations of projected limit ( 200 colonies/ 100 mL) based on average monthly values. About 39% of values also exceed 400 colonies/ 100 mL.

Controls Needed Exhibit A 23 indicates that the facility is not in compliance with its current effluent limit. Hard copy DMR data from the facility indicates that fecal coliform exceedances are most likely the result of exceedances in flow, BOD, and TSS concentrations. In several cases, the exceedances resulted from a damaged clarifier in the biofiltration plant. EPA assumed the facility would need to install a flow equalization tank and optimize the secondary treatment units to achieve consistently lower BOD and TSS levels for compliance with the current fecal coliform limits. Once in compliance with the current limits, additional process optimization of the chlorination system would enable compliance with the projected fecal coliform limit. Exhibit A 24 summarizes the control costs necessary to reduce fecal coliform to the required levels. Costs include process analysis, and process modifications including increasing the chlorine dose from 5 mg/ L to 15 mg/ L, improving mixing conditions through the addition of baffles, increasing contact time from 60 minutes to 90 minutes, and increasing the frequency of maintenance and cleaning of the contact tanks to prevent bacteria build up from once every 2 years to twice a year.

Exhibit A 24. Summary of Compliance Costs, Vega Baja WWTP Cost Component Capital Costs O& M Costs Total Annual Costs1 Process Analysis $ 7,579  $ 715 Process Modifications: Increase Chlorine Dose Improve Mixing Increase Contact Time Increase Maintenance $ 252,304 $ 10,109 $ 21,357  $ 43,520   $ 1,563 $ 67,337 $ 954 $ 2,016 $ 1,563 Total $ 291,349 $ 45,083 $ 72,587 Sources: U. S. EPA ( 2003b); BLS ( 2002); WERF ( 1995). 1. Capital costs annualized at 7% over 20 years plus O& M costs. October 2003 Appendix A. Facility Analyses A   21 References Bureau of Labor Statistics ( BLS). 2002. 2001 Occupational Employment Survey ( OES) State Occupational Employment and Wage Estimates, Puerto Rico. Online at http:// www. bls. gov/ oes/ 2001/ oes_ pr. htm.

U. S. EPA. 2003a. Permit Compliance System ( PCS) Database. Accessed September 10, 2003. Online at http:// www. epa. gov/ enviro/ html/ pcs/ adhoc. html.

U. S. EPA. 2003b. Chlorine Disinfection Model of the WBS Based Cost Models for Drinking Water Treatment Technologies. Final Draft.

Water Environment Research Foundation ( WERF). 1995. Comparison of UV Irradiation to Chlorination: Guidance for Achieving Optimal UV Performance. Project 91 WWD 1. Appendix B Total Annual Cost Calculations October 2003 Appendix B. B   1 Appendix B. Total Annual Cost Calculations This appendix provides a summary of the estimated costs of the proposed rule to the sample facilities, and an explanation of the extrapolation of costs to the total number of potentially affected facilities ( as described in Section 4.1.5).

Exhibit B 1 summarizes the total capital, O& M, and annual costs for each sample facility.

Exhibit B 1. Summary of Estimated Costs to Sample Facilities NPDES No. Facility Type Category Total Capital Costs O& M Costs Total Annual Costs1 PR0023728 Bayamon RWWTP Major Municipal $ 0 $ 0 $ 0 PR0023752 Carolina WWTP Major Municipal $ 0 $ 0 $ 0 PR0025445 Guayama RWWTP Major Municipal $ 0 $ 0 $ 0 PR0025399 Humacao RSTP Major Municipal $ 0 $ 0 $ 0 PR0021555 Puerto Nuevo RWWTP Major Municipal $ 512,187 $ 701,440 $ 749,790 PR0021679 Vega Baja WWTP Major Municipal $ 291,349 $ 45,083 $ 72,587 PR0023442 Boquerón WWTP Minor Municipal $ 0 $ 0 $ 0 PR0020486 Guanica WWTP Minor Municipal $ 99,326 $ 15,360 $ 24,736 PR0020010 U. S. Naval Station  Roosevelt Roads Major Military $ 0 $ 0 $ 0 PR0020044 Fort Allen Training Annex Minor Military $ 60,218 $ 3,961 $ 9,645 1. Represents capital costs annualized at 7% over 20 years, plus annual O& M costs.

To extrapolate the sample facility costs to the universe of affected facilities, EPA first calculated an average annual cost per facility for major municipals, minor municipals, major military, and minor military facilities. EPA then multiplied the average per facility cost by the total number of potentially affected facilities in each discharge category. Exhibit B 2 summarizes the resulting total costs associated with the proposed rule.

Exhibit B 2. Potential Costs to All Facilities Potentially Affected by the Proposed Rule Discharger Category Sample Size Number in Sample with Costs Total Annual Cost for Sample Facilities Annual Cost per Facility Number Potentially Affected Total Annual Cost Major Municipal 6 2 $ 822,377 $ 137,063 19 $ 2,604,194 Minor Municipal 2 1 $ 24,736 $ 12,368 10 $ 123,680 Major Military 1 0 $ 0 $ 0 1 $ 0 Minor Military 1 1 $ 9,645 $ 9,645 2 $ 19,290 Total 10 4 $ 856,758 NA 32 $ 2,747,164 NA = not applicable. October 2003 Appendix B. B   2