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Home My WebLink AboutEMERALD GROVE S12505Onsite File 1 Emerald q t Y' Engineer's Soils Report Emerald Grove, Lots 1-4 Proposed Subdivision of Bob West, Tract A S12505 Municipality of Anchorage Prepared for: Hultquist Homes Inc. 12570 Old Seward Highway, Ste. 204 Anchorage, AK 99515 Prepared By: Pannone Engineering Services, LLC P.O.B. 100217 Anchorage, AK 99510 Submitted By: Steven R. Pannone, P.E. Principal, Civil Engineer November 7, 2019 Emerald Grove, Lots 1-4 Proposed Subdivision of Bob West, Tract A Engineering Report Project Description This soils report is to identify the suitability of the soils on the lot being subdivided for an on-site septic system. This subdivision is part of Bob West, Tract A. This report will detail the soils encountered during the soils investigation, existing topography, impact to surrounding wells and septic system and the suitability of the soils encountered for the use of an on-site wastewater disposal system and water supply system. The four (4) proposed lots will each be approximately 1 acre in size. The lots are undeveloped. Soils Investigation Pannone Engineering Services performed a soils investigation on June 28, 2019, in the area that the subdivided lots will be located. The test pits were excavated by the White Raven Development and were excavated to the maximum extent of the excavator. The test pits revealed a limited variety of soils. We encountered in Test Hole one (TH-1) a layer of organics to a depth of one foot (1.0'), underlain with silty sand with traces of gravel to a depth of fourteen feet (14.0'). The layer of sand and gravel was found to have a percolation rate of 37 minutes per inch. Based on the percolation rate and the appearance of the soil an application rate of 0.45 gallons per day/ square foot may be used as an application rate with a trench type disposal field. We did not encounter bedrock or impermeable soils in the Test Hole one (TH-1). Permafrost was not encountered in the test pit nor is it suspected in this area. Groundwater was not encountered to a depth of fourteen feet (14.0') during excavation or after the 7 -day monitoring period or at high ground water monitoring in October. We encountered in Test Hole two (TH-2) a layer of organics to a depth of one foot (1.0'), underlain with silty sand with traces of gravel to a depth of sixteen feet (16.0'). The layer of sand and gravel was found to have a percolation rate of 27 minutes per inch. Based on the percolation rate and the appearance of the soil an application rate of 0.6 gallons per day/ square foot may be used as an application rate with a trench type disposal field. We did not encounter bedrock or impermeable soils in the Test Hole Two (TH-2). Permafrost was not encountered in the test pit nor is it suspected in this area. Groundwater was not encountered to a depth of sixteen feet (16.0') during excavation or after the 7 -day monitoring period or at high ground water monitoring in October. Emerald Grove, Lots 1-4 Proposed Subdivision of Bob West, Tract A We encountered in Test Hole three (TH-3) a layer of organics to a depth of one foot (1.0'), underlain with silty sand with traces of gravel to a depth of seventeen feet (17.0'). The layer of sand and gravel was found to have a percolation rate of 32 minutes per inch. Based on the percolation rate and the appearance of the soil an application rate of 0.45 gallons per day/ square foot may be used as an application rate with a trench type disposal field. We did not encounter bedrock or impermeable soils in the Test Hole Three (TH-3). Permafrost was not encountered in the test pit nor is it suspected in this area. Groundwater was not encountered to a depth of seventeen feet (17.0') during excavation or after the 7 -day monitoring period or at high ground water monitoring in October. We encountered in Test Hole four (TH-4) a layer of organics to a depth of one foot (1.0'), underlain with silty sand with traces of gravel to a depth of seventeen feet (17.0'). The layer of sand and gravel was found to have a percolation rate of 54 minutes per inch. Based on the percolation rate and the appearance of the soil an application rate of 0.45 gallons per day/ square foot may be used as an application rate with a trench type disposal field. We did not encounter bedrock or impermeable soils in the Test Hole four (TH-4). Permafrost was not encountered in the test pit nor is it suspected in this area. Groundwater was not encountered to a depth of seventeen feet (17.0') during excavation or after the 7 -day monitoring period or at high ground water monitoring in October. Topography The proposed Subdivision is located on mid -hillside portion of O'Malley Road at the intersection of Baronik Street and is surrounded by developed lots. The slope is generally from the southeast to the northwest. The subject area slopes at approximately 5% with no steep slopes in the vicinity. Existing water and wastewater systems The proposed subdivision is located at the intersection of O'Malley Road and Baronik Street, in Anchorage. The existing residential water supply systems on all the surrounding lots are private wells and have a 100 foot protective radius around them (i.e. a new wastewater disposal system may not be located less than 100 feet from these private water wells.) There is a church with a Transient Non -Community well on the lot to the West (PWSID 215867). This well is located over 100' from the septic reserve area but less than 200'. The ADEC issued a waiver for poroposed septics on Emerald Grove, Lot 1 to the Well serving the church to 100'. Emerald Grove, Lots 1-4 Proposed Subdivision of Bob West, Tract A Water Availability This subdivision will be located on the lower Anchorage hillside where water is readily available. The surrounding wells are typically between 110 and 165 feet deep. The static water levels range between 43 and 70 feet deep. The existing well flow data that was available showed that the wells with record data could produce approximately at least 5 gallons per minute. Based on the record research and field data we collected, there appears to be adequate water available for the proposed subdivision without affecting the surrounding wells. The well will be approximately 200 feet deep or less and will likely produce at least 5 gallons a minute. Installing these wells will not affect the production of water wells on the surrounding property. Legal Description Well Depth Static Production Nitrates Water Level MG/L Cabin by the Creek #2, Lot 1 149 70 15 gpm 5/26/2006 <0.1 Cabin by the Creek #2, Lot 2 162 43 15 gpm 1/28/2003 0.704 Cabin by the Creek #2, Lot 3 161 68 10 gpm 12/9/2005 1.41 Higgins Estates, Lot 1 148 63 5 gpm UNK T12N, R3W, Sec 22, Lot 29, N132' 110 59 5.1 gpm 7/11/2011 ND T12N, R3W, Sec22 L4 N2 Less N75' 300 222 30 gpm 12/22/2008 0.1 Klemetsen, Lot 1 110 55 15 gpm 7/30/2015 ND Surface water There are no wetlands or surface water within 100' of this subdivision. Engineering Criteria The soils in this area are typically organics underlain by silty sand and gravel. PES conducted a percolation test on the proposed lots and found percolation rates as shown above, and on the soils logs. The soils encountered in this area are generally medium percolating soils (around 30 mpi). An application rate of 0.45 gpd/sf should be used for the design of a wastewater disposal system Emerald Grove, Lots 1-4 Proposed Subdivision of Bob West, Tract A on the proposed lots 1, 3, and 4- and an application rate of 0.60 gpd/sf may be used for the design of a wastewater disposal system on the proposed lot 2 as shown on the soils logs and in this report. Groundwater was not encountered on this subdivision. Site Information For a subdivision, a site plan stamped by an engineer must show specific areas for the septic system based on the observed percolation rate and Title 15.65.180, Table 2. These areas must meet all set back requirements of Title 15.65. According to Table 2, and area of 10,000 sf must be shown for areas with a percolation rate of 1-5 MPI, an area of 12,000 sf must be shown for areas with a percolation rate of 5-12 MPI, and an area of 14,000 sf must be shown for areas with a percolation rate of 12-24 MPI. The attached site plan shows the reserve areas per these requirements. The Municipality of Anchorage (Moa) Regulations (15.65) govern for single-family homes. These regulations require a minimum of four (4) feet vertical separation between the bottom of a soil absorption system and ground water for a conventional wastewater disposal system, six feet (6') to bedrock or other impermeable layers (tight silts and clays with a percolation rate greater than 120 minutes per inch) and must be located greater than 100 feet horizontally from any surface water (Creeks and ponds). Additionally, the accepting soils must have a percolation rate of less than 120 minutes per inch. A lot must have room for a primary and reserve soil absorption system. [}, Malley Road STORM DRAIN PIPE NO SURFACE WATER RESERVE AREA -4- AREA A 00 Ld RESE R VE AREA WELL (E) cRIE ON -44 AREA Lot 0' Temporary Turnaround acated when 3;d is 7 tpde& —41 WE WELL (E) AND SEPTIC AREA (E) ES VES LOCATED >200' Z7 FROM SUBJECT LOT AIGGV� 96 SEPTIC AREA (E)-/ j_O-T 30 WELL (E) NOTES: PAMONE ENG SVC, LLC Date SOILS REPORT oF. 10/10/2019 P.O. BOX 100217 ANCHORAGE, AK 99510 PHONE (907) 272-8218 FAX (907) 272-8211 Scale EMERALD GROVE, LOTS 1-4 �P.I.D. NO 015-521-16 HULTOUIST HOMES INC. CE 8149 PERMIT NO. BARONIK STREET PLAN Sheet ANCHORAGE, AK 1 OF 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 TEST HOLE 1 BOH ORGANICS SILTY SAND WITH TRACES OF GRAVEL DATE PERFORMED: 6/28119 SOILS LOG - PERCOLATION TEST SLOPE x TH WAS GROUND WATER ENCOUNTERED? N IF YES, AT WHAT DEPTH? -DRY SITE PLAN M M...i.. TH-2 Lot 2 a) �i 43,893sf� C�)H - w o nI /•-MM�yt 1 �6 a L sf 0 i DEPTH TO WATER AFTER MONITORING? -DRY DATE: 7/12/19 DEPTH TO WATER AFTER MONITORING? -DRY DATE: 10/1/19 SLOPE x TH READING DATE CLOCK NETTIME WATERTIME LEVEL READING NETDROP 1 6/28/19 1:30 — 5.66 -- 2 2:00 30 MIN 7.16 1.50 3 2:00 --- 5.66 - 4 2:30 30 MIN 6.50 0.84 5 2:30 --- 5.66 -- 6 3:00 30 MIN 6.48 0.82 PEROLATION RATE 37 (min/inch) PERC HOLE DIAMETER 6 inches TEST RUN BETWEEN 3 FT AND 4 FT COMMENTS: Test hole excavated by WHITE RAVEN DEVELOPMENT. PERFORMED BY: Dan Moran. I CERTIFY THAT THIS TEST WAS PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDLINES IN EFFECT ON THE DATE OF THIS TEST. NOTES: P VNE ENG WC, LLC ��®®a \ Date SOILS REPORT P.O. BOX 102954 ANCHORAGE, AK 99510°F A� 4stt o/�0/2019 PHONE (907) 272-8218 FAX (907) 272-821NTS AF 149 y �d� Scale EMERALD GROVE, LOTS 1-4 P.I.D. No SUBDIVISION OF BOB WEST, TR A TH ®w 015-521-16 Steven F2. Ponnone • ®PERMIT N0. HULTQUIST HOMES INC. �� . CE 8149 ,®� s12505 ST SOILS LOG ANIK NCOHORAGEREAK Ilk eA et OfESSIpN� � SheOF 5 TEST HOLE 2 OR ORGANICS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 BOH 17 18 SILTY SAND WITH TRACES OF GRAVEL DATE PERFORMED: 6/28/19 SOILS LOG - PERCOLATION TEST SLOPE X TH WAS GROUND WATER ENCOUNTERED? N IF YES, AT WHAT SITE PLAN TH-2 1' \44�� Lot 2 a) ,: -- 43,893sf � -+-� \ N (n Mhry /M„�--h4 --_�' h� W TH ui O m t I /> 43 DEPTH? -DRY DEPTH TO WATER AFTER MONITORING? -DRY DATE: 7/12/19 DEPTH TO WATER AFTER MONITORING? -DRY DATE: 10/1/19 iB O SLOPE TH X READING DATE CLOCK NET TIME WATERTIME LEVEL READING NETDROP 1 6/28/19 2:45 --- 6.66 -- 2 3:15 30 MIN 8.57 1.91 3 3:15 --- 6.66 - 4 3:45 30 MIN 7.81 1.15 5 3:45 --- 6.66 --- 6 4:15 30 MIN 7.78 1.12 PEROLATION RATE 27 (min/inch) PERC HOLE DIAMETER 6 inches TEST RUN BETWEEN 3 FT AND 4 FT COMMENTS: Test hole excavated by WHITE RAVEN DEVELOPMENT. PERFORMED BY: Dan Moran. I CERTIFY THAT THIS TEST WAS PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDLINES IN EFFECT ON THE DATE OF THIS TEST. SOILS REPORT P �`eN ENGSVC, LLC � ��® �� Date P.O. BOX 102954 ANCHORAGE, AK 99510 '�� F A�gSl�j� s Qilo/2o19 PHONE (907) 272-8218 FAX (907) 272-8211 � P m �� le NTS EMERALD GROVE, LOTS 1-4 0 P.I.D. NO SUBDIVISION OF BOB WEST, TR A• • • • •. -521-16 Steven • R.• P•anno• ne. • ®PERM17 N0. HULTQUIST HOMES INC. �� . CE 8149 s12505 SOILS LOG A NCOHORAGENIK REAK ��>�D o�Esslo � � SheetOF 5 �® a� ORGANICS SILTY SAND WITH TRACES OF GRAVEL DATE PERFORMED: 6/28/19 SOILS LOG - PERCOLATION TEST SLOPE WAS GROUND WATER ENCOUNTERED? N IF YES, AT WHAT �' 4j�`3 TEPLAI TH-3 B Lot 3 / (D TH-4 43j M' is DEPTH? TEST HOLE 3 DEPTH TO WATER AFTER MONITORING? OR 1 7/12/19 DEPTH TO WATER AFTER 2 -DRY DATE: 10/1/19 3 6.95 1.17 3 4 -- 5.78 _ 5 1:45 30 MIN 6.75 6 5 1:45 --- 7 --- SM/ 2:15 30 MIN GM 8 9 10 11 12 13 14 15 16 17 BOH 18 ORGANICS SILTY SAND WITH TRACES OF GRAVEL DATE PERFORMED: 6/28/19 SOILS LOG - PERCOLATION TEST SLOPE WAS GROUND WATER ENCOUNTERED? N IF YES, AT WHAT �' 4j�`3 TEPLAI TH-3 B Lot 3 / (D TH-4 43j M' is DEPTH? -DRY DEPTH TO WATER AFTER MONITORING? -DRY DATE: 7/12/19 DEPTH TO WATER AFTER MONITORING? -DRY DATE: 10/1/19 w Lot 4 w 43,646sf SLOPE TH X READING DATE CLOCK TIME NETTIME WATER LEVEL READING NETDROP 1 6/28/19 12:45 --- 5.78 --- 2 1:15 30 MIN 6.95 1.17 3 1:15 -- 5.78 _ 4 1:45 30 MIN 6.75 0.97 5 1:45 --- 5.78 --- 6 2:15 30 MIN 6.72 0.94 PEROLATION RATE 32 (min/inch) PERC HOLE DIAMETER 6 inches TEST RUN BETWEEN 3 FT AND 4 FT COMMENTS: Test hole excavated by WHITE RAVEN DEVELOPMENT. PERFORMED BY: Dan Moran. I CERTIFY THAT THIS TEST WAS PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDLINES IN EFFECT ON THE DATE OF THIS TEST. NOTES: T t`I P ®'AT1C �'A,TA"'� STC' LLC l�tL 3�l�li ►3V Liri. P.O. BOX 102954 ANCHORAGE, AK 99510 PHONE (907) 272-8218 FAX (907) 272-8211 � Al SOF ALq� , S 'o- Cb 'Fy�� 49 T �o . • R. Pannone • • • • • • ® �� F . CE 8149 • �� A'�PR ESS10Nq� .:m Z. o®� Date 0/10/2019 SOILS REPORT Scale NTS EMERALD GROVE, LOTS 1-4 SUBDIVISION OF BOB WEST, TR AS HULTQUIST HOMES INC. BARONIK STREET ANCHORAGE, AK P.I.D. NO 015-521-16 PERMIT NO. S12505 SOILS LOG 4e Sh0F 5 TEST HOLE 4 OR ORGANICS 1 2 3 4 5 6 7 SM GM 8 9 10 11 12 13 14 15 16 17 BOH 18 SILTY SAND WITH TRACES OF GRAVEL DATE PERFORMED: 6/28/19 SOILS LOG - PERCOLATION TEST SLOPE X TH WAS GROUND WATER ENCOUNTERED? N IF YES, AT WHAT DEPTH? -DRY DEPTH TO WATER AFTER MONITORING? -DRY DATE: 10/1/19 —4!E FLAN $, P-7 � h �a /��; TH-3 1 C LOBe'��_-M " 1 t 3 (D f TH-4 43, sf hh 0 w Lot 4 -; Lij 43,646sf i hh0 SLOPE X TH READING DATE CLOCK NET TIME WATERTIME LEVEL NETDROP READING 1 6/28/19 12:45 --- 6.54 -- 2 1:15 30 MIN 8.60 2.06 3 1:15 --- 6.54 --- 4 1:45 1 30 MIN 7.11nO.5 5 1:45 --- 6.54 6 2:15 30 MIN 7.10 PEROLATION RATE 54 (min/inch) PERC HOLE DIAMETER 6 inches TEST RUN BETWEEN 3 FT AND 4 FT COMMENTS: Test hole excavated by WHITE RAVEN DEVELOPMENT. PERFORMED BY: Dan Moran. I CERTIFY THAT THIS TEST WAS PERFORMED IN ACCORDANCE WITH ALL STATE AND MUNICIPAL GUIDLINES IN EFFECT ON THE DATE OF THIS TEST. NOTES: P 117�T1C L'TaT!^� SVC, LLC _ �� Date 111�dJLJ Lil�LJ v v i... ��® SOILS REPORT P,O. BOX 102954 ANCHORAGE, AK 99510 '(� °F A�qs�� 0/10/2019 PHONE (907) 272-8218 FAX (907) 272-8211 �y ��r Scale NTS EMERALD GROVE, LOTS 1-4 01 D. NO 16 SUBDIVISION OF BOB WEST, TR A Steven FR. Pannone ®PERMIT No. HULTQUIST HOMES INC. ��F CE 8149 c��® S12T N BARONIK STREET cs '� SOILS LOGANCHORAGE, AK � OPROF S k� Sh5eOF 5 Steven R. Pannone, Principal Registered Professional Engineer E-mail: steveCa)panengak.com October 10, 2019 State of Alaska Department of Environmental Conservation 555 Cordova Street Anchorage, Alaska 99503 Subject: Waiver Request for Separation Distance Septic System to Transient Non -Community Well Bob West, Tract A / Emerald Grove, Lot 1 to T12N, R3W, Sec 22, L4 N2 Less N75' Ladies and Gentlemen: I am writing to request a separation distance waiver from a proposed septic system, on a proposed lot, to a "Transient Non -Community Well". The current lot Bob West, Tract A is being subdivided into four new lots — designated Emerald Grove Subdivision and per Anchorage Municipal Code 15.65 a septic reserve area must be established on each lot. The proposed lot Emerald Grove, Lot 1 will be almost entirely within 200' of the Well Located on T12N, R3W, Sec 22, L4 N2 Less N75' serving the existing New Grace Christian Church. We are requesting a separation distance waiver from the well serving the church to any future septic system serving Emerald Grove, Lot 1. 1. Waiver: We would like to request a waiver for separation distance for the proposed septic system to the well located on the neighboring lot. a. Drain Field (P) to Well (E): A separation distance waiver between the existing Transient Non - Community Well on T12N, R3W, Sec 22, L4 N2 Less N75' to the proposed drain field on the subject property. The distance between the proposed drain field and the well will be 100' or greater. We are requesting a waiver for the drain field to the existing well for a distance of 100'. DEC Criteria: The well on T12N, R3W, Sec 22, L4 N2 Less N75' is a Transient Non -Community Well with a depth of 300 feet and a static water level of 222 feet. The known data for this well is summarized as follows and the Well Log is attached: LOT # WELL STATIC YIELD Well Data H2O Test Soil Well Nitrate DEPTH WATER Date Date Characteristics Log Level LEVEL Data T12N R3W 300' 222' 30gpm 10/4/1985 12-22- Y Y Unknown Sec22 N2 Less 2008 N75' Nitrates: 0.1 MG/L Pi-ysi4cak 33'32 East Manor, AnVl:s^J iwi Clloi (910 7) Crr,X: "' 90 ii _71"2 mo+ Page 2 of 2 The ground water in this area typically flows from the east to the west. The soil cross-sections from the well log were used to calculate the DEC criteria for all components. As outlined under 18 AAC 80.020 and 18 AAC 72.021(a), I have calculated the following points: HANSHEW HTS L4C&4D Sentic Svstem to Well: Distance from sewer system bottom to groundwater 6.0 Soil sorption below sewage system 4.0 Soil permeability below the system 3.0 Water table gradient 0.3 Horizontal separation 3.0 Total Points 16.3 "The sum of the above values could equate to the following conditions: 12-16 - Almost sure to be free from any form of contamination from household sewage." In my opinion, this waiver request meets the above criteria for approval and does not constitute risk to health. I hope the above information will assist you in determining that the waiver should be granted. The proposed installation will not affect the future development of the surrounding or existing lots. If you have any questions or concerns, please contact me at 272-8218. Sincerely, ®e®* ®1aan®ta E OF A4"'11440 Steven R. Pannone CE 8149 i I4®ESS®��Q,®4® Steven R. Pannone, P.E. Owner/Civil Engineer it a;�Ili9 0, B0X �4 tb t2.', t r::fch ,'-ri %'�� s: [, s� +r's (3f""�% }'iii;/�I i?:,.1„�`�! i'a, f"Vita o '.i , �':ii {-?LrCt -,yr>i`ti.1 _�`.'�i.=- Telelsi one: t-9 i) !?- -,^ FAX, [907j 2/2-� 11. 2 _ i'r!ra. SZ1. 01ALASKA. GOVERNOR BILI, I-VALKER October 31, 2019 Mr. Steve Pannone, RE Pannone Engineering Services, LLC. P.O. Box 100217 Anchorage, AK 99510 Department of Environmental Conservation DIVISION OF ENVIRONMENTAL HEALTH Drinking Water Program 555 Cordova Street Anchorage, Alaska 99501 Main: 907.269.3076 Fax: 907.269.7650 thomas.brannan@alaska.gov File: New Grace Christian Church PWSID: 215867 Class: Community Source: Groundwater Re: Emerald Grove Lot 1(Subdivision of Bob West Tract A) Separation Distance Waiver - Source to Proposed Septic Reserve Area Dear Mr. Steve Pannone: On October 10, 2019, this office received your submittal requesting a reduction of the State's minimum separation distance requirements between a community drinking water source and a potential source of contamination. This letter approves the requested reduction in the State's minimum separation distance requirements from 200' to 100' between the drinking water well serving the New Grace Christian Church (NGCC) Public Water System (PWS) and a proposed septic system reserve area for Emerald Grove (EG) Lot 1(a proposed new lot subdivided from Bob West Tract A). The exact location of the proposed septic system and its components to serve the proposed lot 1 will be determined sometime in the future, with this, under this Separation Distance Waiver no component of the noted trench style septic system shall be within 100' of the well serving NGCC. Background Bob West Tract A is existing and is currently being subdivided into EG, Lots 1-4. EG Lot 1 is almost entirely within the 200' protective radius for the drinking water well serving NGCC. Based on existing conditions and Municipal Code, a 16,000 ft' Septic Reserve Area is required. To meet this area requirement, a reduction of the State's minimum separation distance requirement from 200' to 100' has been requested. Waiver Determination As indicated in your submittal, the septic system to serve EG Lot 1 will consist of a trench style drainfield and septic tank with an application rate of 0.45 gallons per day / fe. At its nearest, the septic system and its related appurtenances shall be no closer than 100' from the well serving the NGCC PWS. The NGCC PWS well was drilled in October of 1985; it's casing extends to 296' below ground surface (BGS) and penetrates lenses of sand, gravel, hardpan, and mixes thereof with a static water level of 222' BGS. The following additional items were taken into consideration as part of this waiver approval: 1. From January 2014 to January 2019, source water sampling results for nitrate -nitrite concentration have been non -detect. This suggests that the well is not currently influenced by septic system exfiltration, decomposition of organic matter in soils, and/or erosion of natural deposits. The presence of nitrates in the future may warrant a reevaluation of this