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The City of Hollywood (Fla.) is located in southeast Broward County, with a land area of approximately 29 square miles. The City is primarily a residential community with a population that exceeds 125,000. It has six miles of beachfront property, small concentrations of light industry, and retail and office space within the corporate limits. However, the City is a regional wastewater service provider to areas outside the City that are termed "Large Users." Large users include the following jurisdictions.
• Pembroke Pines
• Pembroke Park
• Portions of unincorporated Broward County
Additionally, the Southern Regional Wastewater Treatment Plant (WWTP) receives secondary treated wastewater from the Towns of Davie and Cooper City for disposal as reclaimed water. Large user agreements exist with each of the six entities discharging to the WWTP specifying standards that must be met. Wastewater originating from the large users enters the City of Hollywood’s collection system through 12 connections. These connections include sampling points and meters that provide data on the quality and quantity of their flows.
The (WWTP) is a 42 mgd wastewater treatment plant owned and operated by the City of Hollywood. The facility was constructed in the 1940s. Currently, it is a Category II, Class A activated sludge plant that utilizes an ocean outfall and reclaimed water for treated effluent disposal. Treated effluent must comply with standards identified in its Federal NPDES permit, State TOP (administratively extended until new permit issued), and State of Florida Surface Water Discharge Standards, Marine Class III (Florida Administrative Code [FAC] 62-302.530). The NPDES and TOP permits will be combined in the State of Florida Domestic Wastewater Permit (DW), which has been applied for and is in review process.
As a part of its ocean outfall permitting requirements, the Hollywood WWTP must sample for lead, copper, cyanide, silver and mercury on a monthly basis. State numerical limits must be achieved for copper, silver and mercury. A Consent Order has provided interim limits for copper and silver (20 ppb and 10 ppb respectively). Cyanide and lead must be reported. In the absence of a specific numerical limit, the City considers the FAC 62-302.530 limits to apply.
General Pretreatment Requirements
The State of Florida Department of Environmental Protection (FDEP), via Florida Administrative Code section 62-625.110, requires the City of Hollywood to implement the pretreatment standards set forth in FAC 62-625. The objectives of the FAC 62-625 pretreatment standards are
• To prevent discharges to wastewater facilities that will interfere with the operation of the facility including interference with its use or disposal of domestic wastewater residuals;
• To prevent discharges to wastewater facilities that will pass through or otherwise be incompatible with wastewater facilities; and
• To improve opportunities to beneficially use domestic wastewater residuals.
FAC 62-625 identifies the requirements for Industrial Pretreatment Programs. Pretreatment programs must be based on legal authority and include, at a minimum, the six requirements outlined herein. At all times, authority and procedure must be fully and effectively exercised and implemented. Each of these requirements must be evaluated to determine whether future action is needed on the part of the treatment.
Changes in the regulatory community primarily focus on the delegation of pretreatment activities from the federal government to the FDEP. The effect of this change is an enhanced ability of the State to monitor pretreatment program implementations. FDEP has created a section in its Domestic Wastewater Division whose primary focus is to monitor pretreatment programs within the State of Florida. The staff within this Division of State government actively inspects and monitors pretreatment programs. Hollywood was one of the first sites inspected within the first year of pretreatment delegation from the EPA to FDEP.
When FDEP audited the City of Hollywood Industrial Pretreatment Program in February 1996, a series of modifications to the program was mandated to meet State standards. The audit reviewed Hollywood’s Sewer Use Ordinance, a program interview, industrial user files, inspections of select industrial users, control mechanisms, compliance monitoring and inspections. Despite the City having an EPA-approved program, a number of deficiencies were found in the program. In-house staff review concurred that only minimal efforts were being spent in this endeavor and little understanding of the collection system existed.
Simultaneously, the WWTP was found in Significant Non-Compliance (SNC) due to violations of metals standards. A compliance schedule was established by the DEP for these violations. The implementation of changes were mandatory for the Industrial Pretreatment Program through DEP Consent Order OGC Case #No. 96-1832. The City was advised that pretreatment scrutiny would be standard procedure for all surface water discharges with metals violations, especially those with pending mixing zone applications.
To meet the requirements in this Consent Order, the following actions have been taken.
Comprehensive Revision to User Database
An industrial waste survey of every commercial and/or industrial user in the service area was undertaken. This included reviews of more than 9,000 addresses in the seven jurisdictions that contribute raw wastewater. Accomplished to date are the following.
• Creation of a database identifying sewered commercial utility accounts with detailed information identified, including name, address and usage.
• Field inspection of all commercial utility accounts connected to sewer system.
• Provision of a brief survey to each business requesting information on the nature of business, chemicals and materials used (provided in Appendix L).
• Priority for inspection and sampling has been assigned to all businesses, and activity has commenced.
• A modified multi-jurisdictional agreement has been drafted.
• A modified sewer use ordinance has been drafted.
Develop Local Industrial Discharge Limits
• The Industrial Pretreatment Program sampled the WWTP influent to develop initial data on WWTP removal ratios, and the characteristics of WWTP influent, and sampled the collection system of the City and the Large Users.
• All Industrial Pretreatment Program permittees were reorganized to include self-monitoring sampling results, city monitoring sampling results and chemical inventories/MSDS and have had monitoring locations reviewed and modified as necessary.
Administrative Procedures Created
• A Permitting Procedure Manual.
• A Sampling Procedure Manual.
The Regulatory Compliance Program (RCP) FY96 budget was adjusted during the City’s mid-year budget cycle (4/96). Prior to the adjustment, the only funding dedicated to the Industrial Pretreatment Program was $6,000 for contractual services (laboratory analyses for sampling). This funding was available via the WWTP Laboratory Account. More than $102,000 was transferred into the RCP Budget as a result of a Mid-Year Budget adjustment, including more than $74,000 for laboratory services, the purchase of composite samplers, gas detector and related consumable equipment (sampler tubing, bailer, etc.).
The current budget provides funding for more than $450,000 directly related to the Industrial Pretreatment Program Operations. Of that total, $200,000 was budgeted for contractual laboratory services. The budget submittal also provided for a regulatory compliance officer and additional compliance technicians, for a total of five positions.
The Regulatory Compliance Program began activities to meet the 11/30/98 Consent Order deadline in early 1996. The compliance technicians physically visited and inspected more than 9,000 businesses within the WWTP service area. All information learned about each business was recorded and computerized.
More than two million gallons per day of industrial flow were identified during the Local Limit Development Program. The identification and quantification of average daily flow from potential industrial discharges was necessary to determine the flow and pollutant loading to the WWTP that is domestic and uncontrollable by the pretreatment program. While the EPA requires sampling of WWTP influent and effluent for four days to develop Local Limits for only six pollutants (cadmium, chromium, copper, nickel and zinc), and recommends sampling for four other parameters (arsenic, cyanide, silver and mercury), Regulatory Compliance analyzed Hollywood’s wastewater system for more than 220 pollutants, including analyzing the WWTP influent and effluent for all 220 pollutants once per month for 13 consecutive months.
All local limit sampling performed by the compliance technicians followed established standard operating procedures addressing preservatives, sample containers, sample collection order, specific equipment to minimize contamination of trace metals, specific cleaning procedures to minimize trace metal contamination and the implementation of tamper-proofing of collected samples. Field blanks were taken at each sampling event to ensure the integrity of the sample result. Laboratory analysis detection levels for each parameter sampled were selected to ensure the lowest detection limits were utilized with locally available technology. The program developed what they term "near-clean techniques" for sampling. Analysis of samples using true clean techniques and the City’s near-clean methodology show minimal difference. Several research quality labs have observed the near-clean techniques and have provided a favorable response to its use.
As a result of reviewing nearly 9,000 sample results from local laboratories, the Regulatory Compliance Program has made the following observations.
Silver–The City of Hollywood received a Consent Order to improve the pretreatment program based on WWTP violations of copper and silver. However, only one of the 13 samples for silver exceeded the State Standard (by 0.5 ppb). All silver results in the domestic sampling locations, and in the industrial locations were less than 0.5 ppb. Silver analyzed by a lab with an EPA Level 4 QA/QC Plan and a silver detection limit of 6 ppm showed less than 1 ppb was standard. Silver was not the problem it was anticipated to be.
Copper–The average WWTP effluent violation for copper (for which the Consent Order was issued) was 21.6 ppb. The State Discharge Standard is 2.9 ppb. The average composite sample level of copper obtained by Regulatory Compliance was 2.8 ppb. Three of the 13 samples for copper obtained by Regulatory Compliance exceeded the State Discharge Standard, but no samples exceeded 10 ppb.
Copper was identified at industrial locations at an average level of 19 ppb. The copper level in domestic sampling locations ranged from 10—20 ppb. Copper in domestic discharges is not within the purview of the Industrial Pretreatment Program and cannot be addressed through public education. Copper levels in domestic discharges are believed to be due to copper piping and the presence of copper in the raw, untreated water supply. The average WWTP removal ratio for copper was 87 percent. With this ratio, the WWTP appears to have the ability to effectively remove copper loading. In fact, all effluent copper levels were less than the State Discharge Standard when influent copper levels ranged from 30—50 ppb.
Lead–The City of Hollywood has reported WWTP effluent lead levels in excess of the State Discharge Standard to FDEP in the past, most recently in 9/98. Ninety-two percent of Regulatory Compliance’s composite WWTP effluent lead samples were less than 1 ppb. One-hundred percent of the 24-hour discreet effluent lead samples were less than 1 ppb (with an average of 0.27 ppb). All lead results in the domestic sampling locations and in the industrial locations were less than 0.5 ppb. No evidence was found that lead is a problem.
Cyanide–The City of Hollywood has reported WWTP effluent cyanide (free, not amenable to chlorination) levels over of the State Discharge Standard of total cyanide (cyanide) to FDEP in the past. Cyanide users discharging wastewater to the Hollywood WWTP represent approximately less than 1 percent of the total WWTP flow. With the knowledge of the relatively low end-of-pipe concentrations for direct dischargers, a special sampling project indicated cyanide was present where it was expected and known to be present. Nitrates can have a positive interference with cyanide analyses if not properly addressed by the laboratory, while sulfides, even in concentrations below the detectable limits, can cause false positives in cyanide analyses without the appropriate field preservation methods. The presence of cyanide in the collection system and in WWTP influent and effluent was determined not to be a problem despite prior results to the contrary.
Iron–The average domestic concentration for iron was 1.02 ppm, while the State Discharge Standard for iron is 0.3 ppm. The effects of iron leaching from the sewer collection piping system and in groundwater in western areas contributes to the problem. The Hollywood potable water supply contains an average iron concentration of less than 0.05 ppm.
Oil and Grease–The State Discharge Standard for oil and grease is 5 ppm. The average WWTP influent level in the regulatory compliance sampling was 19 ppm. The average effluent level was 1.8 ppm (an average removal ratio of 90 percent). While the effluent level never exceeded the State Discharge Standard in 13 sampling events, the City is considering implementing a grease-trap inspection program, or developing a surcharge limit for oil and grease as its presence in the wastewater collection system is important to utilities operations.
The following pollutants were determined not to be an issue for the City.
• Hexavalent Chromium, Zinc, Nickel, Aluminum, Mercury.
• Beryllium, Arsenic, Mercury, Cadmium, Thallium, Selenium, Chromium, Antimony.
• All other Pesticides, Herbicides, PCBs, Radioactive Elements.
• Volatile Organics, Semi-Volatile Organics.
• COD, BOD, TSS, TKN.
Conclusions and Recommendations
Based on the City’s efforts with pretreatment and its review of lab quality, the following conclusions have been reached.
• Improper sampling techniques and/or laboratory analysis procedures may have been responsible for results indicating that the City had violated its permit standards, not the actual effluent.
• Because of faulty results, the City may have been subjected to a consent order for which no true violations may have occurred.
• There is no indication that industry is a significant contributor of pollutants to the Hollywood WWTP.
• The Hollywood WWTP is effective at removing the amount of pollutants it receives.
As a result of these findings, the City recommends the following.
• A continued, active sampling and pre-treatment inspection program.
• The continued use of "near clean" sampling techniques, developed in house and performed in house, for all sampling events. The City has demonstrated that this level of care in sampling significantly reduces the potential for bad sampling events and contamination.
• Laboratory services should be based on the ability to perform and not low bid. Routine, ongoing comparisons of a lab’s work for quality control purposes is required.
• Quality Assurance/Quality Control programs and certifications do not necessarily equate to labs that can provide consistent, high-quality results.
• High-quality trace metals sampling is difficult to obtain. It is worth the cost to use high-quality, nationally recognized labs to perform these analyses, especially when setting local limits that have default values at one-half detection.
• Grease control is a problem in many systems that can be addressed through a pretreatment program.
About the Authors:
Frederick Bloetscher, P.E., is the director of Engineering, Operations and Planning for the Florida Governmental Utility Authority, Hollywood, Florida. He was previously the deputy public utilities director for the City of Hollywood, Florida
Lisa Meday-Futo is the regulatory compliance manager for the City of Hollywood, Florida.
Whitifeld R. Van Cott is the public utilities director for the City of Hollywood, Florida.
Robert Fergan, P.E., is an engineer with Hazen and Sawyer, Raleigh, North Carolina