Individual Individual APP Applications APP Applications - PowerPoint PPT Presentation

Individual Individual APP Applications APP Applications Hydrogeologic Study Hydrogeologic Study Mason R. Bolitho, R.G. Mason R. Bolitho, R.G. July 15, 2010 July 15, 2010 SWVP-013320

APPLICABLE RULES Arizona Administrative Code Title 18, Chapter 9, Article 2, Part A R18-9-A202 SWVP-013321

R18-9-A202(A)(1) Topographic map of the facility location and contiguous land area showing the known use of adjacent properties, all known water well locations within ½ mile and a description of well construction details and well uses SWVP-013322

A.R.S. §49-244(1) “The pollutant management area is the limit projected in the horizontal plane of the area on which pollutants are or will be placed. The pollutant management area includes horizontal space taken up by any liner, dike or other barrier designed to contain pollutants in the facility. If the facility contains more than one discharging activity, the pollutant management area is described by an imaginary line circumscribing the several discharging activities.” SWVP-013323

R18-9-A202(A)(4) A summary of past and proposed facility discharges , indicating: � Chemical, physical and biological characteristics � Rate, volume, and frequency of discharges � Location of the discharge and a map outlining the PMA described in A.R.S. §49- 244(1) SWVP-013324

A.R.S. §49-244 “The point of compliance is the point at which compliance with aquifer water quality standards shall be determined. The point of compliance shall be a vertical plane downgradient of the facility that extends through the uppermost aquifers underlying that facility.” SWVP-013325

DISCHARGE IMPACT AREA A.R.S. §49-201 “‘Discharge impact area’ means the potential areal extent of pollutant migration, as projected on the land surface, as the result of a discharge from a facility.” SWVP-013326

R18-9-A202(A)(8) A hydrogeologic study that defines the facility’s Discharge Impact Area (DIA) for the expected life of the facility . An abbreviated study or no study may be allowable. The study shall demonstrate: � Discharge will not cause or contribute to an AWQS exceedance � If an AWQS exceedance already exists, no additional degradation will occur SWVP-013327

R18-9-A202(A)(8)(b) In the hydrogeologic study, ADEQ may require: � A description of surface and subsurface geology, including all borings (i) � The location of any surface water bodies (ii) � Characteristics of the aquifer and units with limited permeability (iii) SWVP-013328

R18-9-A202(A)(8)(b) � The rate, volume, and direction of surface and groundwater flow including hydrographs & maps (iv) � The precise location or estimate of the 100-year flood plain (v) � Documentation of existing water quality in aquifers underlying the facility (vi) � Any known soil contamination (vii) SWVP-013329

R18-9-A202(A)(8)(b) � Assessment of the potential to cause leaching of pollutants (viii) � For a USF, assessment of leaching or migration of contaminated groundwater (ix) � Any expected changes in water quality (x) � Any expected changes in groundwater elevation or flow direction (xi) SWVP-013330

R18-9-A202(A)(8)(b) � A map of the DIA (xii) � The criteria and methodologies used to determine the DIA (xiii) SWVP-013331

R18-9-A202(A)(9) and R18-9-A202(A)(10) � A detailed proposal for ALs, AQLs, DLs, monitoring, compliance schedules � Closure or post-closure strategies SWVP-013332

R18-9-A202(A)(11) � Any other relevant information required by the Department to determine whether to issue a permit SWVP-013333

R18-9-A202(B) An applicant shall demonstrate the ability to maintain technical capability and shall submit the following: � Pertinent licenses or certifications � Relevant professional training � Relevant work experience SWVP-013334

POTENTIAL HYDROLOGY DEFICIENCIES � Hydrology that doesn’t make sense � “We already submitted that!” � Unsealed documents � No/insufficient supporting data � No AL/AQL/DL or monitoring proposal � Inappropriate well construction � Non-response responses � No PMA or DIA maps � No information on existing water quality SWVP-013335

POTENTIAL HYDROLOGY DEFICIENCIES � Insufficient hydrogeologic study � No method of DIA determination � Inappropriate POC locations � No information on downgradient drinking water sources � No evaluation of leaching potential � No identification of uses of nearby wells � No identification of local aquifer(s) � No verification of disposal capacity or mounding analysis SWVP-013336

POTENTIAL HYDROLOGY DEFICIENCIES � No/insufficient discharge characterization � Incomplete or no well inventory (e.g., only WELLS-55 database reviewed) � No description of geology � No information on nearby property ownership or land uses � No groundwater flow direction or rate provided � No information on construction of nearby wells SWVP-013337

POC LOCATIONS A.R.S. §49-244 � The Director shall designate point or points of compliance for each facility receiving an individual permit. � Point of compliance is in a vertical plane downgradient that extends through the uppermost aquifers. � For a hazardous POC, the point of compliance is the downgradient limit of the PMA. SWVP-013338

POC LOCATIONS A.R.S. §49-244 For a hazardous POC well, an alternate POC location may be proposed by the applicant. The alternate location may NOT: � Be located as to result in increased threat to a drinking water source � Be located further downgradient than: � The property boundary � An existing or potential drinking water source � 750 feet from the edge of the PMA SWVP-013339

POC LOCATIONS A.R.S. §49-244 For a non-hazardous POC well, ADEQ shall take into account: � Volume and characteristics of pollutants � Practical difficulties � Existing vs. new facilities � Water conservation & augmentation � Site-specific facility characteristics (e.g., hydrology, geology, soil chemistry, pollutant concentrations in the aquifer, climate) SWVP-013340

POC LOCATIONS IMPORTANT POINTS � Don’t confuse discharge compliance sampling points with POC wells � POC wells must by statute be downgradient; in areas exhibiting mounding, POCs may be required radially � Hazardous POC wells must be located at the edge of the PMA unless otherwise located using strict statutory limitations � Non-hazardous POC wells shall be located using site specific characteristics SWVP-013341

POC LOCATIONS IMPORTANT POINTS � A POC does not necessarily have to be a physical monitor well, but may instead be a POC location only; this determination depends on site-specific characteristics � If a POC location (rather than a well) is originally required, a POC well may be required in the future if necessary (e.g., after exceedances of Alert Levels in facility discharges) SWVP-013342

POC LOCATIONS IMPORTANT POINTS � A POC well will typically be required to monitor an AZPDES discharge � ADEQ may require additional POCs as needed in the future, depending on site characteristics and discharges SWVP-013343

SWVP-013344 Typical POC location

TYPICAL GROUNDWATER MONITORING SCHEDULE � General chemistry parameters (major cations & anions, pH, TDS, EC)—quarterly � Nitrate species—monthly � Coliform bacteria—monthly � VOCs—biannually � Metals—quarterly � Water levels—quarterly � Data reported quarterly or semi-annually SWVP-013345

MONITOR WELL CONSTRUCTION There is no one standard well construction, however: � Screens should not be submerged in most cases � Screens should not be too long � Pump position is not very significant � Filter packs should not be too long � Modification of existing wells may be allowable SWVP-013346

SWVP-013347 Construction Generic

SWVP-013348 Subm erged Screen

SWVP-013349 Long Screen

SWVP-013350 Long Filter Pack

Monitoring I njection W ells SWVP-013351

SWVP-013352 Groundw ater Perched

SWVP-013353 Com pletion Open Hole

SWVP-013354 Sand in W ell Bottom

Sand in W ell Bottom w ith Bentonite/ Grout SWVP-013355

DISCHARGE IMPACT AREA R18-9-A202(A)(8)(b) The rule requires a DIA map and the methodology by which the DIA was identified. � Models are generally used to establish the DIA � Provide assumptions on which the DIA was based, e.g., hydraulic conductivity, gradient, effective porosity, discharge, etc. � Provide map of DIA SWVP-013356

DISCHARGE IMPACT AREA POLLUTANT MANAGEMENT AREA SWVP-013357

DISCHARGE IMPACT AREA POLLUTANT MANAGEMENT AREA PMA DIA POC Impoundment Groundwater Flow Direction SWVP-013358

HELPFUL HINTS � Use http://www.sahra.arizona.edu/wells/ for well locations and use data � Use local aquifer test data when available � Use ADWR modeling data when appropriate � Recent GWSI water-level data may be available � Use FEMA maps for floodplain analysis � Pay close attention to monitor well construction � Use ADWR imaged records for well completion reports and driller’s logs � Read the rules! SWVP-013359

Questions? SWVP-013360