WATER SERVICES DEPARTMENT 91 ST Ave./23 rd Ave. Wastewater Treatment Plant Toxicity Identification Evaluation (T.I.E.) Professional Services PROJECT NOs. WS90100103 and WS90200023 NOTIFICATION LETTER #1 August 16, 2016 This notification letter shall become a part of the Request for Qualifications for the above referenced project. The attached document entitled “City of Phoenix / 91 st Avenue Wastewater Treatment Plant / Toxicity Reduction/Toxicity Identification Evaluation / Workplan dated July 2012 is included at Exhibit “A” to the Request for Qualifications (RFS) referenced above. Donna Wiltshire Contract Specialist CITY OF PHOENIX DESIGN AND CONSTRUCTION PROCUREMENT City of Phoenix OFFICE OF THE CITY ENGINEER DESIGN AND CONSTRUCTION PROCUREMENT 200 West Washington Street, 6 th Floor Phoenix, Arizona 85003-1611
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WATER SERVICES DEPARTMENT
91ST Ave./23rd Ave. Wastewater Treatment Plant
Toxicity Identification Evaluation (T.I.E.) Professional Services
PROJECT NOs. WS90100103 and WS90200023
NOTIFICATION LETTER #1
August 16, 2016 This notification letter shall become a part of the Request for Qualifications for the above referenced project. The attached document entitled “City of Phoenix / 91st Avenue Wastewater Treatment Plant / Toxicity Reduction/Toxicity Identification Evaluation / Workplan dated July 2012 is included at Exhibit “A” to the Request for Qualifications (RFS) referenced above.
Donna Wiltshire Contract Specialist CITY OF PHOENIX DESIGN AND CONSTRUCTION PROCUREMENT
CCiittyy ooff PPhhooeenniixx OFFICE OF THE CITY ENGINEER
DESIGN AND CONSTRUCTION PROCUREMENT 200 West Washington Street, 6th Floor
Phoenix, Arizona 85003-1611
M:\Projects\0742\002-02\Doc\TRE_Workplan_rev(B4).doc i
List of Tables .............................................................................................................. iii List of Figures ............................................................................................................. iii List of Abbreviations ................................................................................................... iv
SECTION I INTRODUCTION ..................................................................................... I-1
SECTION II PERMIT REQUIREMENTS ..................................................................... II-1 Limitations and Monitoring Requirements for Conventional Parameters .................... II-1 Whole Effluent Toxicity Testing Requirements ............................................................ II-1 Accelerated Whole Effluent Toxicity Testing ............................................................... II-3
SECTION III PLANT DESCRIPTION .......................................................................... III-1
SECTION IV RESPONSIBILITIES FOR RESPONSE ACTIONS FOR TOXICITY REDUCTION EVALUATION-RELATED STUDIES ............................................... IV-1
SECTION V PROTOCOLS FOR SAMPLING AND ANALYSES FOR ACCELERATED TESTING AND TOXICITY REDUCTION EVALUATION ...................................... V-1
Sample Collection and Transport to Water Services Laboratory ................................. V-1 Chain-of-Custody Forms ............................................................................................. V-1 Chemical Analyses ...................................................................................................... V-1 Sample Storage ........................................................................................................... V-2 Sample Shipment to AECOM ...................................................................................... V-2
SECTION VI ACCELERATED TESTING PHASE ....................................................... VI-1 Notification Procedures ............................................................................................... VI-1 Split samples ............................................................................................................... VI-1 Activities In Response to Notification of Toxicity ......................................................... VI-1 Activities in Response to WET Test Exhibiting Toxicity During Accelerated Testing .. VI-4
Development of Detailed Workplan ...................................................................... VI-4 Initiation of TIE Studies ......................................................................................... VI-5
SECTION VII TOXICITY IDENTIFICATION AND REDUCTION EVALUATIONS ....... VII-1 Objectives .................................................................................................................... VII-1 Approach ..................................................................................................................... VII-1
Toxicity Identification Evaluation .......................................................................... VII-3 Phase I Toxicant Characterization .................................................................... VII-3 Phase II Toxicant Identification ......................................................................... VII-7 Phase III Toxicant Confirmation ........................................................................ VII-9
Toxicant Source Identification .............................................................................. VII-9 Toxicity Control Evaluation ................................................................................... VII-10
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Direction of TIE and TRE laboratory studies; contact point for coordination when effluent samples are shipped to AECOM for TRE study and when TRE samples are sent back to City for chemical analysis
970-416-0916 Extension 312
(970) 490-2963 4303 West La Porte Ave. Ft. Collins CO 80521
The workplan presented herein is in general accord with that described in the Toxicity Reduction
Evaluation Protocol for Municipal Wastewater Treatment Plants, EPA/833/B-99/002 (August
1999). For convenience, the singular is used below (“toxicant,” “compound,” “stream,” etc.),
although it is recognized that more than one toxicant may be detected and may need to be
reduced in order that the objectives of the TRE can be met.
OBJECTIVES
The specific objectives of this TRE are as follows:
Evaluate the pattern and degree of effluent WET test failures;
Identify, to the extent necessary to eliminate WET test failures, the constituent responsible for the observed failures;
Determine, as appropriate, the source of the substance causing WET test failures;
Evaluate and select toxicity reduction programs and/or technologies that result in the elimination of WET test failures so that compliance with the permit is maintained;
Develop an implementation strategy for controlling effluent toxicity.
APPROACH
The steps in achieving the TRE objectives are shown in Figure VII-1. The first step in the
process is to finalize this workplan. The TRE process shown in Figure VII-1 is based on the
following EPA documents:
Methods for Aquatic Toxicity Identification Evaluations, Phase I Toxicity Characterization Procedures, Second Edition, EPA/600/6-91/003;
Methods for Aquatic Toxicity Identification Evaluations, Phase II Toxicity Identification Procedures, EPA/600/R-92/080;
The objective of toxicant identification is to identify the specific toxicant or effluent characteristic
that is responsible for WET tests exhibiting toxicity. Phase I results provide an understanding of
the characteristics of the toxicant that is used to select the appropriate Phase II steps. The
description of Phase II approaches for several commonly identified toxicants (or groups of
toxicants) are provided in the following paragraphs.
Non-polar Organic Compounds Non-polar organic compounds are a group of toxicants commonly encountered in municipal effluents. One of the difficulties encountered with non-polar organic compounds is that most effluents contain large numbers of organic compounds; given this fact, direct analysis of the effluent is almost useless for initially identifying candidate toxicants. To resolve this problem, techniques have been developed to isolate and concentrate causative toxicants prior to chemical analysis.
The primary indication of non-polar organic toxicity is complete removal of toxicity by SPE. In these cases, the first step in identification is to elute the causative toxicant from the SPE column using a series of eight different methanol concentrations. Toxicity tests are used to show which methanol fraction(s) contain the causative toxicant. In some cases, high performance liquid chromatography (HPLC) and gas chromatography/mass spectroscopy (GC-MS) techniques can extend these initial results to allow identification of the specific causative toxicant.
Using these techniques, the toxic fractions from the initial separation are concentrated and further separated into 25 fractions using HPLC. Toxic HPLC fractions are then concentrated and submitted for chemical analysis. Procedures for non-polar organic identification are probably the most intensive of those used for commonly encountered toxicants.
Ammonia The presence of ammonia can confuse the results of other tests if TIE studies are not carefully designed. In general, chemical characterization of effluent samples prior to testing provides an indication that effluent may contain toxicity due to ammonia. AECOM has encountered ammonia toxicity in a large number of effluents; with the exception of toxicity attributable to TDS, ammonia is AECOM's most commonly identified effluent toxicant.
For cases where ammonia is suspected to cause chronic toxicity, tests are conducted to determine whether ammonia is, in fact, the only causative toxicant. Procedures used include ammonia spiking, zeolite treatment, graduated pH tests, and testing under a carbon dioxide-enriched atmosphere.
Heavy Metals AECOM has developed a technique to sub-categorize metal toxicity and speed identification of the causative toxicant using the EDTA and oxidant reduction tests. An advantage of this technique is that it directly addresses the bioavailability of the metal, not just its chemical presence.
Several Phase I tests may show responses if heavy metals are present; the exact responses depend on the metals involved. EDTA and/or thiosulfate addition will reduce the toxicity of most cationic metals. Removal of toxicity by filtration at pH 11 is also common, as many metals are not soluble under basic conditions. Though not designed to remove metals, the SPE tests may reduce toxicity somewhat, due to non-specific binding to the SPE column. In most cases, however, metal toxicity breaks through the SPE column fairly rapidly. Manipulations at pH 3 sometimes increase metal toxicity, presumably due to solubilization or mobilization of previously non-toxic metal forms.
Identification studies for metals are commonly less resource-intensive than identification studies for other toxicants. Direct chemical analyses are frequently sufficient.
Total Dissolved Solids The failure to eliminate a toxic response in any of the Phase I characterization tests is consistent with toxicity due to TDS. In many cases, TDS toxicity can be approximated using sodium chloride, but research conducted by AECOM has clearly shown that the toxicity of saline waters is dependent on the specific ionic composition. AECOM has developed salinity/toxicity relationships (STRs). The STRs are a series of logistic regression equations that predict the toxicity of any combination of major ions to three test species: C. dubia, Daphnia magna, and fathead minnows. Splitting samples between two laboratories and a mock effluent containing major ions at the same concentration as in the actual effluent sample can be used to help confirm TDS toxicity.
Surfactants, Flocculants, and Related Chemicals Removal of the toxic response by aeration, filtration, and SPE is typical for these compounds. Analytical methods for surfactants are difficult, and generic screening methods are not available. However, innovative methods are available to assist in identifying surfactants. WET test exhibiting toxicity associated with surfactants in effluents can result from the incomplete treatment of detergent or from water treatment chemicals used within the facility.
Chlorine Chlorine is perhaps the most easily identified of all toxicants common to effluents. A WET test exhibiting toxicity caused by residual chlorine is characterized by the presence of measurable residual chlorine in the sample, the removal of the toxic response with sodium thiosulfate addition, and the rapid degradation of the toxicant during sample storage.
Toxicant identification studies will be performed jointly by AECOM and LSS. AECOM will
manipulate the samples (extraction, ion exchange, etc.) to prepare them for chemical analyses.
LSS or an AECOM contract laboratory will perform the chemical analyses.
The laboratory analyses will be performed in accordance with accepted quality assurance
protocols. Appropriately sensitive analytical methods will be used, and if possible EPA
approved methods will be used. In some cases, it may not be possible to quantify or identify a
pollutant with approved methods. If this is necessary, the laboratory should report the method
and equipment used to conduct the analyses. Most analyses can be performed by LSS. Others
will be shipped to a contract laboratory licensed by the State of Arizona.