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HomeMy WebLinkAbout912027.tiff • 10QII Waste Management of North America,Ino. .NaOr Mountain Region 5660 Greenwood Plaza Blvd.•Englewood,Colorado 80111 Suite 4244303/770-3324 December 9,1991 • • Mr.Rod Allison Weld County Department of Planning Services 915 10th Street,Room 342 Greeley,CO 80631 SUBJECT: NORTH WELD SANITARY LANDFILL • Dear Mr.Allison: - - • Enclosed is a letter to Mr.Wes Potter,Director of Environmental Services,Weld County Health Department,which describes two minor changes associated with construction of the clay liner at the North Weld Sanitary Landfill(NWSL). In accordance with Section 34 of the Certificate of Designation Approval Development Standards for the NWSL,Waste Services Corporation(WSC)an affiliate of Waste Management of Colorado,Inc.hereby files these changes with the Weld County Department of Planning Services. The changes consist of the following: 1. Modifying the QA/QC testing frequency from 1 test per 100-foot spacing for each 6 inch lift of liner material to 1 test per 370 cubic yards of liner material. 2. Modifying the moisture content specification from 0 to 4 percent of optimum moisture content to-2 to+2 percent of optimum moisture content. •As you will note,these changes are supported by ATEC Associates,Inc.,the independent QA/QC project consultant. Also as referenced in the enclosed,we have reviewed these items Mr.Potter and Ms.Austin Buckingham,Colorado Department of Health,who have concurred with the changes. Please call me should you have any questions about the enclosed. Sincerely, Tom Schweitzer,.P.E. . Environmental Engineering Manager ro 91202.1 -: PL-017-1 Letter to Rod Allison December 9, 1991 Page 2 TS/mak Enclosures cc: Bill Hedberg, WSC w/o enclosures Brad Keirnes, WSC w/o enclosures f:\ts\120991L1.doc /Qii. Waste Managementorth America.Inc. . lieMountain Region 5660 Greenwood Plaza Blvd.•Englewood.Colorado 80111 Suite 424.303/770-3324 • November 19, 1991 Mr. Wes Potter , Director of Environmental Protection Services Weld County Health Department 1517 16th Avenue Court Greeley, CO 80631 SUBJECT: NORTH WELD SANITARY LANDFILL (NWSL) Dear Mr. Potter: This letter is intended to summarize our meeting of November 13, 1991 regarding two minor changes recently identified by Waste Services Corporation (WSC), an affiliate of Waste Management of Colorado,Inc.,pertaining to the NWSL clay liner construction project which is nearing completion. The two changes pertain to QA/QC testing frequencies for field moisture/density and moisture content specifications for clay liner placement. The following information in support of these changes is attached: Attachment 1 Excerpts from the Development Standards included as part of the Certificate of Designation (CD) Approval by the Weld County Board of Commissioners Attachment 2 Summary of QA/QC observation and testing frequencies for the clay liner construction prepared by ATEC Associates, Inc. (ATEC), the independent QA/QC project consultant Attachment 3 Summary Table which compares the testing program used for this project and the program identified in the CD Development Standards Attachment 4 Moisture content recommendations for clay liner placement by ATEC QA/OC TESTING FREQUENCIES FOR FIELD MOISTURE AND DENSITY In Attachment 1, section 7d of the CD Development Standards states that testing shall be preformed "at no less than a 100-foot spacing for each six-inch lift of liner material". The frequency used for this project was 1 test per 370 cubic yards of liner material which approximately equates to a 142-foot spacing for each six-inch lift. Although a literal comparison between the two frequencies indicates that the frequency used for this project complies with the CD requirement, we believe the intent of the CD requirement is that testing should be performed at intervals no greater than 100 feet. D a Letter to Wes Potter November 19, 1991 Page 2 WSC believes the QA/QC testing program implemented for this project is sufficient to provide the necessary assurances that the liner was constructed in accordance with the specifications identified in the CD. In support of this position, the following is provided: • Prior to construction and as discussed in Attachment 2, test fills were constructed using onsite, representative materials under the supervision of an ATEC representative to verify materials suitability and performance. As shown in Attachment 3, this testing included 160 field moisture and density tests, 12 particle size tests, 12 Atterberg Iimits tests, 12 Proctor tests, and 12 laboratory permeability with moisture/density tests. During testing,parameters such as moisture content and the number of equipment passes over the liner material were varied and the performance (e.g. permeability) of the material was then determined. This testing, which is in addition to the requirements of CD Development Standards, increased the level of confidence in the material and established the parameters by which construction of the liner was undertaken. • During construction, laboratory permeabilities with moisture/density testing were conducted. As shown in Attachment 3, this testing was performed at the frequency of 1 test per 5000 cubic yards of liner material used. This testing is also in addition to the requirements set forth in the CD Development Standards. MOISTURE CONTENT SPECIFICATIONS FOR CLAY LINER PLACEMENT Section 7b of the CD Development Standards states that "the moisture content of the material shall be maintained from zero to four percent of the optimum moisture content". The moisture content used for this project ranged from -2 to +2 percent of the optimum moisture content. As previously stated and as discussed in Attachment 4, test fills were constructed prior to liner placement to verify suitability and performance of the liner material. During testing, moisture content was varied and resulting permeabilities were determined. Based on the test fill results, ATEC determined that to meet permeability specifications the moisture content range for clay liner placement should be from -2 to +2 percent of optimum moisture content. In consideration of the above points supporting these two changes,you concurred during our November 13 meeting that the QA/QC frequency of 1 test per 370 cubic yards for field moisture and density and the moisture content range of -2 to +2 percent of optimum moisture content were appropriate for this project. I discussed these changes with Ms. Austin Buckingham, Colorado Department of Health (CDH), by telephone on November 15, 1991. Based on my description of the changes,Austin did not envision any concerns with the changes. By copy of this letter, I am forwarding the enclosed support information to Austin. In addition, I am also sending a copy of this letter to.the Weld County Department Pc; Letter to Wes Potter November 19, 1991 Page 3 of Planning Services as required by Section 34 of the CD Development Standards which requires that such changes be filed with this Department. At your earliest convenience, I request written confirmation from Austin and you regarding your concurrences with these changes. Should you or Austin have any questions or require additional information, please call me. Sincerely, Tom Schweitzer, P.E. Environmental Engineering Manager Enclosures TS/mak cc: Austin Buckingham, CDH Rod Allison, Weld County Department of Planning Services Bill Hedberg, WSC Brad Keimes, WSC Steve Kuehr, ATEC f:\ts\111891L1.doc r art i ,, Telefax Numbers: $3°x. 1�tA paf' Main Building/Denver cle � bc ,:: (303)322-9076 3fi to.P 4210 East 11th Avenue Ptarmigan Place/Denver ROY ROMER '• `'` (303) 320-1529 Governor Denver, Colorado 80220-3716 Phone (303) 320-8333 First National Bank Building/Denver (303)355.6559 JOEL KOHN ,I !4t Grand Junction Office Interim Executive Director COLORADO 1M (303)248-7198 1.1/1AJi�tiW Pueblo Office DEPARTMENT (719)543-8441 OFAHEALTH December 3 , 1991 "' !L J Tom Schweitzer, PE Waste Management of North America, Inc. �_� 0 �? 1991 Mountain Region 5660 Greenwood Plaza Blvd. 'Sl�(F`•'�'t"9 Weld�e�s^.• Englewood, Colorado 80111 RE: QA/QC Clay Liner North Weld Sanitary Landfill Weld County, Colorado Dear Mr. Schweitzer: The Hazardous Materials and Waste Management Division (the Division) of the Colorado Department of Health has reviewed your November 19, 1991 submittal regarding modifications to the North Weld Sanitary Landfill clay liner moisture/density testing frequency and moisture content. Based on the information provided, the Division finds that the proposed testing frequency and moisture content are adequate to ensure that the clay liner will be placed according to the designed permeability. Therefore, the modifications are deemed to be sufficient. Please contact me at this office, if you have any additional questions. Sincerely, G_ Austin N. Buckingham Geologist Solid Waste and Incident Management Section Hazardous Materials and Waste Management Division cc: R. Allison, Weld County Planning Department W. Potter, Weld County Health Department file: WLD/NOR 1 MAQ 16, 1988 SCRAP TIRE RECYCLINGQGULATION •=v) 2 3 Statement of Basis and Purpose 4 5 Colorado's scrap tire problem is indeed serious. Over 2 million tires are 6 discarded each year and only a small .portion are recycled or retreaded. Most 7 tires are placed in ever-growing stockpiles and others are burned, buried or 8 illegally dumped. A tire stockpile fire in Hudson in June, 1987, burned for 9 four days releasing noxious smoke and toxic gases and contaminated soils. . 10 This fire cost on the order of $100,000 to extinguish. Scrap tire stockpiles 11 are known to provide prolific breeding habitats for infectious disease 12 carriers such as mosquitoes and rats. 13 14 Currently, stockpiling of scrap tires is uncontrolled and little incentive ) 15 exists for recycling. These regulations, which were developed by a 16 broad-based committee consisting of tire stockpilers, disposers, recyclers, 17 landfill operators and local and state health officials, are aimed at 18 mitigating adverse effects from scrap tire piles. The issues addressed by the 19 regulations include safe storage practices such as adequate security, access, 20 communication abilities, signage, emergency contacts, submittal of a tire fire 21 plan, and evidence of recycling;activities. 22 23 Tire stockpiles less than 10,000 in number, those that are generally 24 maintained by tire retailers and tire retreaders, generally do not present the 25 serious problems that larger stockpiles present. It is the Department's 26 position that these stockpiles should not be required to obtain Certificates ,27 of Designation unless public health or environmental problems are occurring. ATTACHMENT 2 ATEC Assoctes, Inc. .o - .. . . _ • V 7000 East 47th Avenue Drive,Suite 900 Denver,Colorado 80216 [303]377-2832, FAX # [303]377-2873 November 13, 1991 Waste Management of Colorado 5660 Greenwood Plaza Boulevard, Suite 424 • Englewood, CO 80111 Attn: Mr. Tom Schweitzer, P.E. Subject: Summary of QA/QC Observation and Testing Clay Liner Construction North Weld County Sanitary Landfill - Module 1 ATEC Project No. 41-123064 Gentlemen: ATEC Associates, Inc. (ATEC) has provided QA/QC.services for clay liner construetion at the subject site. Test fills of the liner material were conducted in order to evaluate the acceptable range in moisture; density and compactive effort which would provide the required laboratory vertical hydraulic conductivity. Results of the test fills showed that the required parameters were being achieved with as few as two (2) complete coverages (passes) of the compactor. During construction, the liner material was monitored with a series of tests to verify the . materials suitability and performance. Particle size (ASTM D1140) tests were performed for each 1,000 cubic yards of material. Atterberg limits (ASTM D4318) and moisture- density relationships (standard Proctor, ASTM D698) tests were performed for each 3,000 cubic yards. Laboratory vertical hydraulic conductivity tests(ASTM.D5084)were performed for each 5,000 cubic yards of in place liner. As of this date, test results are available for five (5) out of a total of nine (9) of the hydraulic conductivity samples. The results show that all the tested samples were less permeable than the maximum allowable specified value. The contractor was required to make five (5) complete passes with his compaction equipment for each.six (6) inch lift. Number of passes and lift thicknesses were observed in the field by ATEC's resident engineer. Field moisture content/density tests (ASTM D2216/D2922 and D1556) were performed for each 370 cubic yards of material placed. In the few instances where the moisture or density was insufficient, the contractor was directed to rework the entire area represented by the failing test and subsequent tests showed passing results. • • • • A Subsidiary of American Testing and Engineering Corporation Consulting Environmental, Geotechnica/and Offices in Major U.S.Cities/Since 1958 Materials Engineers . t . C ' Waste Management of Colorado November 13, 1991 Page 2 . • This QA/QC approach establishes performance criteria during the test fill. Field observation verifies that the criteria established from the test fill were utilized during construction. The field observations are supplemented by moisture content density and • laboratory vertical hydraulic conductivity tests to verify the anticipated results. It is our opinion that the amount of observation and testing is adequate to provide the level of confidence in day liner performance as intended by the Certificate of Designation. We are happy to be of continued service to you on this project. Please contact the undersigned if you have any questions. Very truly yours, ATEC ASSOCIATES,"ca., \ BOup Eipiii//e,„ of PROF% ♦\\ fc.oir /i / . air, . d ..0. O a, 0 90- le. .... 6713 a Steven C. Kuehr, P.E. a 24369 i - Donald R Ganser, C.P. Senior Project Engirt .. ;4, District M ---anager tiummittO R?aarisiar.« cc: Mr. F. Glen Odell, P.E. =MOMENT• 4 • ATEC AssociGtesI Inc. a v 7000 East to7 o 8021 Drive, Sutte 900 • V Denver, Colorado 802'IB (3031377-2832, FAX# [3031 377-2873 • • November 13, 1991 • Waste Management of Colorado 5660 Greenwood Plaza Boulevard, Suite 424 Englewood, CO 80111 • Attention: Mr. Tom Schweitzer, P.E. • Subject Moisture Content for Clay Liner Placement North Weld County Sanitary Landfill - Module 1 ATEC Project No. 41-12306 Gentlemen: ATEC Associates, Inc. (ATEC) has conducted clay liner test fills, associated laboratory testing and observed and tested clay liner construction for the above referenced project. The attached laboratory test results provide the relative compaction,,optimum moisture • content (ASTM D698) and as-compacted moisture content for 12 "undisturbed" thin wall tube samples obtained from the test fills. It can be seen from these data that 8 of the 12 test fill samples were less permeable than the construction specified maximum laboratory vertical hydraulic conductivity of 1 X 10.7 centimeters per second (cm/s). The moisture content for these samples ranged from 7.4 percent below optimum to 2.1 percent below optimum. The remaining four test fill samples which did not meet the construction specified laboratory vertical hydraulic conductivity requirement had as-compacted moisture contents ranging from 6.4 percent below optimum to 3.1 percent below optimum. Based upon the test fill results it was determined that to meet the specifications for laboratory vertical hydraulic conductivity the moisture content range for clay liner placement during construction should be within -2 to +2 percent of the optimum moisture content at the specified minimum density of 95 percent standard proctor (ASTM D698) maximum dry density. We are happy to be of continued service to you on this project. If you have any questions, please contact the undersigned. Very truly yours, • ATEC ASSOCIATES, II��ul�aumunnrrru/rr r. • Pp9 ((CCr/S'.,,. c,...44:10. r kGe4o.cv A� EOf PROF Steven C. Kuehn P.E! r� r = v�°� w''o Senior Project Engine�'y's 24369 •C= Donald R. Gasser, C �7; : � t'+die+,�� z District Manager ci 6711 •\ % SCK/Idf ' -k„ ionrit • ...........\s —. \\\ • t N Attachment "'rrtanuum�ao 11O'41 Ot3 cc: Mr. F. Glen Odell, P.E. PROFESSIOOL A Subsidiary of American Testing and Engineering Corporation Consulting Environmental,Geotechnical and Offices in Major U.S.Cities/Since 1958 Materials Engineers e \ DEPARTMENT OF PLANNING SERVICES PHONE(303)356-4000,EXT.4400 91510th STREET ' GREELEY,COLORADO 80631 • COLORADO October 3, 1991 Brad Keirnes, General Manager Waste Services Corporation 6037 77th Avenue Greeley, CO 80631 Subject: Clarification of soil storage area for overburden excavated in association with Special Review Permit Number 895, located in part of the SW4 of Section 7, T7N, R66W of the 6th P.M. , Weld County, Colorado. Dear Brad: Thank you for the September 30 letter clarifying the height of the soil storage area. The information presented is not considered a major change from the plans or development standards as approved by the Board of County Commissioners. The soil storage area shall parallel the north property line of the special review permit area and it will be a maximum three hundred (300) feet wide and fifty (50) feet in height. Please call or write if you have any questions. Sincerely, Rod Allison Principal Planner RDA/sfr 112oz3 MA? ,F suptE NEN'rA L. Sot L STotAGE AREA v ,` \ G'' -R' ;:5:4 4 . .3\ L44 ; ."P(.. .1;1•50--c`f \'tea... )' l :, � , ; .. c 1 1lJJJ / ) f / _. , , ., ___„, , „.q.,,,ti . (.,., , .,;„ i . ,..„.... _ , .. ......„..„.... , ,,,... . ., ) "1,N• \ r\,. cA(. ‘‘._-... 'xi) C ) iv., s . , -u. +,p • - 'e -1/12”-..\ -.1...7•:.:;1 Fc\ 6\/\.• _ tr • the _ ,y•_— a. ,( _. :=:*. •. • 6• • �'�;�>� _.: �:. I . ., •`� . ,333 \ \ e._ /I ( / \A'1` 6.0 1. , • ` a a,y `\ ri, \ • r"-`` \ ., AR\ \ 1MATE�SLT OUN[4' Y\ GN. \ ,SUP 1_AREA �4 \- \$.1-1 \I\ �'° a \ \ 1 .\ i, \ �°eNN��a., :i �, ; \ ,/ j i �! \, o ,. `�rc 1 .rte,\`\. l ✓. I, ( � /% �\\`O -.ae.p Ir— t� �pZ y\ r` ^a �m chi ( , � _-ti ..:,-4 )\ \w �� :; Hwy l•g h .....,s ‘ ..‘Ni\)°.\\ ti tr:r.&\ \.r l\ Chi °' �\r f �.�'- 'ill ° (�, r• . N I v vorto' N'—ii \s......1. )\ti, . ? 7 Apo\:. \ D,... j ki?\sr,:k?\rit.J\ rit‘:04.:V7 .1 1 �r�\ \sas.i, :t«i• fir%�\, • 11{.:x....-,— sm+ 1...\\2 n V\\\\\\:- !.—ti . y Waste Services CORPORATION September 30 , 1991 • Rod Allison Department of Planning Services Weld County 910 10th Street Greeley, Colorado Re: Clarification of Request Dated September 23 , 1991 Dear Mr. Allison: This letter serves to clarify my request, dated September 23 , 1991 , for your consent to establish a supplementary soil storage zone along the north perimeter of the North Weld Sanitary Landfill. Upon our receipt and review of your consent to this request limiting the stockpile area to 25 feet in height, our technical staff informed me that the adequacy of the 300 foot width we specified was based on an assumed soil stockpile height of 50 feet above existing topography. These dimensions were calculated based on the total quantity of material for which additional storage area is required. In defining a supplemental area to meet this need, our engineers sought to minimize the consumption of productive dry land on our adjacent property while still limiting the stockpile to a height that will be fully screened from view by our extensive landscaped berming along Highway 14 . As I indicated to you this morning on the telephone, a stockpile height of 50 feet in this area will be fully shielded from view by our landscaped berming. Also, for your information, the approved final elevation for the landfill area along our north site boundary is a minimum of 75 feet above existing topography, or at least 25 feet higher than the 50 foot stockpile height that is necessary. Therefore, we request your revised consent to a stockpile height of 50 feet. I apologize for any inconvenience I may have caused you. Thank you again for your assistance with the proper planning and monitoring of this facility. Sincerely, C. Bradley Keir General Manager cc: Wes Potter, Weld County Health Department 6037 SEVENTY-SEVENTH AVENUE • GREELEY, COLORADO 80634 • (303) 330-2641 Di or DEPARTMENT OF PLANNING SERVICES PHONE(303)3564000,EXT.4400 915 10th STREET IGREELEY,COLORADO 80631 C. COLORADO September 24, 1991 Brad Keirnes, General Manager Waste Services Corporation 6037 77th Avenue Greeley, CO 80634 Subject: Soil storage area for overburden excavated in association with Special Review Permit Number 895, located in part of the SW4 of Section 7, T7N, R66W of the 6th P.M. , Weld County, Colorado. Dear Brad: Thank you for the September 23 letter and map describing the supplemental soil storage area. The information presented is not considered a major change from the plans or development standards as approved by the Board of County Commissioners. Based upon today' s telephone conversations and submitted information, the soil storage area shall parallel the north property line of the special review permit area and it will be a maximum three hundred (300) feet wide and twenty-five (25) feet in height. Please call or write if you have any questions. Sincerely, /paean— Rod Allison Principal Planner Waste Services CORPORATION September 30 , 1991 Rod Allison Department of Planning Services Weld County 910 10th Street Greeley, Colorado Re: Clarification of Request Dated September 23 , 1991 Dear Mr. Allison: This letter serves to clarify my request, dated September 23 , 1991 , for your consent to establish a supplementary soil storage zone along the north perimeter of the North Weld Sanitary Landfill. Upon our receipt and review of your consent to this request limiting the stockpile area to 25 feet in height, our technical staff informed me that the adequacy of the 300 foot width we specified was based on an assumed soil stockpile height of 50 feet above existing topography. These dimensions were calculated based on the total quantity of material for which additional storage area is required. In defining a supplemental area to meet this need, our engineers sought to minimize the consumption of productive dry land on our adjacent property while still limiting the stockpile to a height that will be fully screened from view by our extensive landscaped berming along Highway 14 . As I indicated to you this morning on the telephone, a stockpile height of 50 feet in this area will be fully shielded from view by our landscaped berming. Also, for your information, the approved final elevation for the landfill area along our north site boundary is a minimum of 75 feet above existing topography, or at least 25 feet higher than the 50 foot stockpile height that is necessary. Therefore, we request your revised consent to a stockpile height of 50 feet. I apologize for any inconvenience I may have caused you. Thank you again for your assistance with the proper planning and monitoring of this facility. Sincerely, C. Bradley Keir General Manager cc: Wes Potter, Weld County Health Department 6037 SEVENTY-SEVENTH AVENUE • GREELEY, COLORADO 80634 • (303) 330-2641 -ce • Waste Services CORPORATION September 23 , 1991 Rod Allison Department of Planning Services Weld County 910 10th Street Greeley, Colorado Re: Storage of Soil at the North Weld Sanitary Landfill Dear Mr. Allison: As we discussed today by telephone, Waste Services Corporation has determined the need to have supplemental soil storage area for overburden being excavated at the North Weld Sanitary Landfill. This need has arisen due to the total quantity of material initially being excavated and our preference to limit the height of our soil stockpiles so as to minimize any potential negative impacts from our operations . To best meet this need, we intend to stockpile this additional material on adjacent property we own in a 300 foot wide storage zone parallel to our north site boundary line (see attached map) . This stockpile area will be maintained in the same manner as proposed and approved as part of the Design and Operations Plan, Use by Special Review Permit and Certificate of Designation for this facility. We request your consent to this action at your earliest convenience so as to facilitate the efficient construction and operation of this facility. Thank you for your consideration and ongoing assistance. Sincerely, C. Bradley K it es General Manage CBK/kbc enc. cc: Wes Potter, Weld County Department of Health 6037 SEVENTY-SEVENTH AVENUE • GREELEY, COLORADO 80634 • (303) 330-2641 ast tsg - t.rvkes CORPORATION July 15 , 1991 Board of Weld County Commissioners JUL 15 RECD 915 10th Street Greeley, CO 80631 Dear Commissioners : I wish to take this opportunity to inform you that effective' July 12, 1991 , Waste Services Corporation has merged with Waste Management of Colorado. This action was taken to enable Waste Services Corporation to continue our commitment to meeting Weld County' s solid waste management needs in a more comprehensive manner. As a small family business , we determined that we needed additional resources and means to do so, as well as to meet the increasing regulatory, financial and competitive demands of our industry. Upon realizing our limitations , we sought and selected the company whom we believe is best committed to the same principles by which we have done our best to conduct our business . We believe that the addition of Waste Management' s expertise and strength to Waste Services ' ongoing operations will result in our continuation of what we trust has been cost-effective and environmentally-sound service to our customers and to Weld County. Waste Services Corporation will continue in its ownership , development and operation of the Central Weld and North Weld Sanitary Landfills . I intend to continue in my present management role. If you have any questions about this matter, I would b,e happy to try to answer them at your convenience. Thank you. Res ectfully, C. Bradley Keirnes President CBK/kbc cc : Don Warden Wes Potter Rod Allison Lee Morrison 6037 SEVENTY-SEVENTH AVENUE 0 GREELEY, COLORADO 80634 • (303) 330-2641 Hello