Hansen Cement expansion proposal in Cupertino - position paper

By Raj Vasant Abhyanker

Tour of Hansen Cement today, national gas alternative to coal, and covering of limestone piles - opportunites to improve?

The Hansen Cement factory has been in operation since the 1930s and delivers approximately 65% of the cement requirements for Santa Clara County. It is the largest Cement factory in the bay area according to John, and one of the largest in California. The plant runs 24 hours per day, with trucks coming in and out each day of the week. There are limestone mining and cement manufacturing operations currently on the site. The Hansen Cement factory also used to make aluminum, but that operation ceased about 20 years ago. The Hansen Cement factory just sold its mining operations to a large German conglomerate, Heidelberg Cement in a transaction which just closed last Thursday August 23. Much of the 3200 acres that the Hansen factory owns is hillside land adjacent to Cupertino which has significant slope gradients (may be only suitable for 10 acre lot size hillside residences if the site were rezoned residential in the next 50 years. Hansen Cement factory currently does not want to rezone its land).

Approximately 700 trucks pass down the Stevens Creek/Foothill corridor each day according to an estimate of David Knapp (the Cupertino City Manager) from the Hansen Quarry and the Stevens Creek quarry. John placed this number a few hundred a day lower for those trucks originating from Hansen alone (the rest may come from the Stevens Creek quarry, which is a a much smaller operation on Foothill Rd.).

Part of the Hansen Cement property is located in Palo Alto, part of it in Cupertino, and the vast majority in an unincorporated area of Santa Clara County.

Hansen Cement has a reclamation plan currently being evaluated b the County of Santa Clara that is coming up for re-evaluation in 2010. The Hansen Cement factory has asked to triple an area currently designated for mining operations after 2010. Much of the request stems from the fact that mining operations are already located there without permit (which may have been in place before 1975 when a new SAMARA act took place). During our tour, I discovered that there are two large piles of limestone that are dropped from overhead conveyor belts that are exposed to the air and which are not in covered chambers. When there is wind, I imagine dust from these piles or rock are spread into the air.

In fact, Hansen has a covered chamber to control such dust in another part of the quarry, but this mid grade and high grade limestone earlier in the manufacturing process is directly dropped in an uncovered environment. There is a large "clay" chamber next to these piles of limestone which is currently being unused (e.g., abandoned because of process improvements). I asked whether this clay chamber can be used to store the mid-grade and high-grade limestone instead of directly having the limestone exposed to the air. John said he would find out more about this, and it seemed like perhaps at least this is possible to help reduce air particulates.

Much of the constant plume of smoke from the factory comes from the Coal fired furnace. The Coal is hauled in by train from San Jose between 1 and 4 pm in the afternoon by Pacific Railroad (a few years ago the train started coming at 10pm which made neighbors next to the tracks in Cupertino very upset). I discovered that the furnace is designed to accept Natural Gas, and there is a pipe going to the plant for Natural Gas. I think we neighbors can ask our local and county government to provide incentives to use Natural Gas instead of coal (natural gas is much cleaner burning).

Hansen Cement has requested to open a new mining pit in its 2010 plan, closer to homes in the city Cupertino off Foothill Blvd and Stevens Creek Road (between there and the Stevens Creek Quarry near the the reservoir). Many neighbors do not want Hansen to open a pit there because it is closer to residents and because of health concerns from operations at the new pit. The new pit will be visible to Cupertino home owners near Rancho San Antonio (in the hills near the radio tower), and will be in lower elevation than the current mining operations. The Hansen Cement factory claims that only a limited area of land near Rancho San Antonio will be able to see the new pit/mining operations.

About a decade or two ago, a group of neighbors put political pressure to create a scenic easement so that similar lower elevation mining operations on a different side of Hansen (one facing Palo Alto and Los Altos) so that their views of trees and natural landscape will not be diminished from the quarry/mining of the hillside. However, no such effort has been made in Cupertino.

The new 2010 plan having the new pit will be more visible at least from the Rancho San Antonio park to Rancho San Antonio area neighbors in Cupertino. However, since this park is frequented by many residents all over Cupertino and Los Altos, I think the scenic loss from Rancho San Antonio may affect a broader group of residents and concerned neighborhoods. We should understand the scenic impacts of the proposed expansion more.

Also, many neighbors are concerned about traffic down Stevens Creek and Foothill Road from this quarry. I asked John what creative possibilities there may be to reroute traffic. Any new roads to connect the quarry to the 280 freeway would be very difficult because a new road would have to either go through the Palo Alto open space reserve or through residential areas. As such, that is not a realistic option. Also, hauling cement back from by the trains that deliver cement to the factory is unpractical according to John, because much of the concrete manufacturing facilities are now portable and close to construction sites (e.g., concrete needs to be poured within 2 hours of being created from cement). The trains all lead back to San Jose and return empty after dropping off coal to the Hansen Cement factory. However, Hansen says that many of their customers are located in the peninsula. As a result, they need large trucks to pick up cement directly from the factory. Hansen has mandated that rock carrying trucks be washed prior to their leaving the quarry, and that truckers slow down when leaving and approaching the quarry (to prevent hazards and noise pollution to neighbors). For some reason, cement carrying trucks (as opposed to rock carrying trucks) are not required to be washed which may contribute to the road level dust on Stevens Creek and Foothill.

A picture is taken of each truck and visitor who approaches the Hansen Cement factory from Stevens Creek and who exceeds a 25 mile speed limit placed by the factory any time during a 24 hour period. Trucks who violate the speed limit are warned by the company that they will not be able to buy cement if they continue to exceed speed concerns. Many neighbors still complain about the noise, as not all trucks follow this speed limit request.

John is very active in Cupertino civic groups such as the Rotary, the Cupertino Community Services, the Chamber of Commerce, and in other organizations. John does not live in Cupertino however, he lives in San Jose. He has worked at Hansen for 9 years and previously worked in the semiconductor industry. John is a nice guy, and is very likable. Hansen Cement donates money to a variety of local groups and events in Cupertino, is active in local government, and in general has been a consistent donor to local causes and neighborhood groups.

In summary, during the tour, I discovered that there are areas where I think we can ask Hansen to make improvements if I am elected on the Cupertino City Council. These areas are (1) use of natural gas instead of coal (2) covering of the large mid-grade and high grade limestone deposits prior to processing in the furnace to reduce air particulates during windy times. It will be difficult for us to ask the quarry to stop operations, as they have private property rights on their land and have been in operation before the neighborhoods surrounding their lands were built.

Raj Abhyanker