HYDRO24688

• Permit No: M1977344
• IBM Index Class Name: Hydrology
• Doc Date: 6/7/2004
• Doc Name: Groundwater Monitoring Report
• From: Holcim ‎(US)‎ Inc.
• To: DMG
• Media Type: D
• Archive: No

1. Introduction
Blasland, Bouck & Lee, Inc. (BBL) was retained by Holcim, Inc, to provide technical support for
Mine Permit Technical Revision TR-06 (TR-06) to State of Colorado Mining Permit No. M-77-
344 for the Holcim Portland plant and quarry. The Holcim Portland plant and quarry is located in
Fremont County, Colorado (Figure 1). The total area of the Holcim property is approximately
3,400 acres. In partial fulfillment of the Colorado Division of Minerals and Geology's
requirements for TR-06, a Groundwater Monitoring Plan (GMP) was developed for the
approximately 1,330 acres included within the boundaries of the mining permit (Site) (Figure 2)
(BBL, 2002). The main purpose of this GMP is to meet the requirements of the Colorado Mined
Land Reclamation Board's (MLRB) Construction Materials Rules and Regulations Rule 3.1.7 for
the protection of existing and reasonably potential future uses of the unclassified groundwater
located beneath the quarry (MLRB, 2001). These requirements have been triggered by the
disposal of cement kiln dust (CKD) into previously mined sections of the Site, and the potential
for leachate from CKD to adversely impact ambient groundwater quality for existing and
reasonably potential future uses.
In support of the GMP, the third quarter of the required additional fow quarters of groundwater
monitoring at monitoring well MW-10 was conducted in April, 2004. This document describes
the procedures followed during measwement of depth to groundwater at all quarry monitoring
wells and piezometers and collection of the groundwater sample at MW-1Q, and presents the
results of the groundwater depth measurements and groundwater sample laboratory analysis. The
remainder of this Introduction section presents the history of the site that is relevant to
groundwater quality. Section 2 describes the field activities for the measwement of groundwater
levels, and sampling of existing monitoring wells. Section 3 presents results for the groundwater
analyses and groundwater elevation measurements. Section 4 presents a description of future
work. Cited references are provided in Section 5.
1.1 Site History
The Portland plant, located on the southern side of the Arkansas River, until recently consisted of
three (3) long, wet kilns with a combined cement production of approximately 937,000 tons per
year (tpy). The Plant currently uses a single dry kiln process for production of cement with a
capacity of 2,094,000 tpy. The facility utilizes afive-stage preheater/precalciner tower to prepaze
material for the kiln. The tower includes heat-exchanging cyclones (i.e., preheater) in which the
dry feed is preheated and partially calcined by the kiln's hot exit gasses prior to entering the
actual kiln. A secondary firing device (i.e., precalciner) in the lower stage of [he preheater further
calcinates the materials. CICD, a waste material from cement production, is dust that is generated
in the cement kiln and associated equipment. Using the prior wet kiln process, approximately
100,000 tpy of cement kiln dust (CKD) was generated during the production of cement at the
Portland plant (Resowce Geoscience, Inc. (RGn, 1999)). The current CKD production rate
ranges from 28,000 tpy to 72,000 tpy. The production of CKD strongly depends upon the
chemistry of raw materials, type of process and the design of gas velocities in the kiln. Other
factors such as kiln performance and dust collection systems play vital roles. To reduce dust
emissions, a pug mill is used to add water to CKD prioi to transporting it to the disposal azea.
Historically, sludge from nearby Fremont Sanitation District wastewater treatment plant had been
added to the CKD disposal area as a daily cover. The sludge also served as a means of CKD dust
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