HomeMy WebLinkAbout20102347.tiff I64;-. D
PUBLIC WORKS DEPARTMENT
1111 H STREET, P.O. BOX 758
GREELEY, COLORADO 80632
WEBSITE:
WWW.CO.WELD.CO.US
W.C EXT.
.CO.US
(itPHONE: (970) 356-4000,E 3750
FAX: (970) 304-6497
COLORADO Weld County Planning Department
September 15, 2010 GREELEY OFFICE
Colorado Division of Reclamation, Mining, & Safety SEP 2 07n1n
Attention: Jared Ebert RECEIVED
1313 Sherman Street, Room 215
Denver, CO 80203
Re: Lafarge West, Hamm Pit, Permit No. M-1987-176
Dear Mr. Ebert,
Weld County Public Works has recently become aware of a pending reclamation
release request from Lafarge West for its Hamm Pit located in or about section 4, T2N.
R68W. The mining activity has impacted the way in which the FEMA mapped floodplain
functions.
FEMA requires that changes such as 100-year flood water surface elevations, floodplain
boundaries, and floodway boundaries be documented and accepted through their Letter
of Map Revision process (LOMR). The Federal Regulations that apply include but are
not limited to the following and can be found in: 44CFR 60.3(b)(3), 60.3(b)(7), and 65.3.
As DRMS should be aware, FEMA, the State of Colorado Water Conservation Board,
and Weld County have floodplain regulations which potentially impact how the site can
be used after reclamation. The above mentioned agencies also have regulations in
place regarding the erosional stability of any fill that may be left in the St. Vrain River
floodplain at the completion of mining.
The mining activity has potentially impacted the hydrologic balance and function of the
St. Vrain River. DRMS Rule 34-32 5-116(4)(h) requires that changes to the hydrologic
balance of the affected land be minimized. Since the function of the floodplain is a
piece of the hydrologic balance, we request that Lafarge show what impact their mining
activity has had on the 100-year flood water surface elevations and floodplain functions.
To date, Lafarge has not provided any evidence to Weld County or the DRMS showing
how their mining and reclamation activities have impacted the 100-year flood water
surface elevations.
DRMS Rule 34-32.5-116(4)0) requires that areas outside of the affected land shall be
protected from damage occurring during the mining operation and reclamation. As
stated above, Lafarge's mining and reclamation activities may have changed the
conveyance of the floodplain in the 100-year flood. Since the currently mapped
floodplain extends beyond Lafarge's property, the potential exists for surrounding
roperty owners to be impacted or even damaged by the mining and reclamatio
nnu crt ac.R 2010-2347
' /O-V-act°
Pagel o(2
M\PLANNING-DEVELOPMENT REVIEWER-Use by SpeciaS RevieM3rd AmUSR-1199 Hamm Pit\3rd AmUSR-1199 DRMS Letter 9-1S-10.docx "7/ tai '
r
activities that have occurred on Lafarge's property. To date, Lafarge has not provided
any evidence to Weld County or the DRMS showing how their mining and reclamation
activities have not impacted property owners within the mapped 100-year floodplain.
In order be compliant with FEMA requirements to documents changes to mapped
floodplains, Weld County respectfully DRMS not to release any portion of the mine site
until such time as FEMA has approved a LOMR which documents the impacts that the
mine has had on the 100-year floodplain and the citizens of Weld County.
Sincerely,
64 ,
Clay Kimmi, P.E., CFM
Drainage and Floodplain Engineer
Weld County Public Works
Original: .Iareal Ebert.DIMS
P(': 3"l;Ant(SR-I I 99
CC: Kin'Ogle,Manning Services
Page 2 of 2
M\PLANNING-DEVELOPMENT REVIEVAUER-Use by Special Review\3rd AmUSR-1199 Hamm Pit\3rd AmUSR-1199 DRMS Letter 9-15-10 docx
Hello